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Table of Contents for April 2003 · Volume 37 · Number 4
Viral Hepatitis
Durability of serologic response after lamivudine treatment
of chronic hepatitis B (*Human Study*)
Jules L. Dienstag, Janusz Cianciara, Selim Karayalcin, Kris V.
Kowdley, Bernard Willems, Stanilav Plisek, Mary Woessner, Stephen
Gardner, Eugene Schiff
Forty subjects with chronic hepatitis B and hepatitis B e antigen
(HBeAg) seroconversion following lamivudine therapy in previous
trials were monitored after treatment to assess the durability
of serologic responses. Patient follow-up began a median of 4.3
months after completion of therapy in previous trials. At months
2, 4, 6, 9, and 12 of year 1, and every 6 months thereafter, we
tested for HBeAg and hepatitis B surface antigen (HBsAg), hepatitis
B virus (HBV) DNA, and alanine aminotransferase (ALT). After a
median (range) of 36.6 (4.8-45.6) months of follow-up monitoring,
HBeAg seroconversion was demonstrated at the last visit by 77%
(30 of 39) of patients. In a post hoc analysis of a slightly different
population of all 65 patients with HBeAg seroconversion in previous
trials, the 3-year durability of HBeAg seroconversion measured
from the time immediately after discontinuing lamivudine therapy
was 64%. Nine (9 of 40, 23%) patients were HBsAg negative at the
last assessment. Seventy-four percent (17 of 23) of patients with
baseline undetectable HBV DNA and normal ALT maintained these
responses at the last visit. Eight patients (8 of 40, 20%) initiated
retreatment for reappearance of HBV markers, and 7 showed biochemical
and/or virologic improvement (including regained HBeAg seroconversion
in 2). No safety issues of concern emerged. In conclusion, most
HBeAg responses achieved during lamivudine therapy were durable,
and most responders experienced prolonged clinical benefit after
HBeAg seroconversion and subsequent discontinuation of lamivudine.
Lamivudine retreatment for reappearance of hepatitis B markers
can achieve resumption of viral suppression. (HEPATOLOGY 2003;37:748-755.)
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Long-term suppression of hepatitis B e antigen-negative chronic
hepatitis B by 24-month interferon therapy (*Human Study*)
Pietro Lampertico, Ersilio Del Ninno, Mauro Viganò, Raffaella
Romeo, Maria Francesca Donato, Erwin Sablon, Alberto Morabito,
Massimo Colombo
To assess whether extended treatment with interferon improves
the outcome of hepatitis B e antigen (HBeAg)-negative chronic
hepatitis B, 101 consecutive patients were treated with 6 MU of
interferon alfa 2b 3 times weekly for 24 months. During the 68-month
study, 30 patients (30%) had a sustained response (i.e.,
normal serum transaminase levels and undetectable hepatitis B
virus DNA by non-polymerase chain reaction [PCR] assays), and
15 cleared serum surface antigen. Twenty-five nonresponders, 16
relapsers, and 30 who discontinued treatment were considered treatment
failures. Multivariate analysis predicted a sustained response
for young age (odds ratio, 0.94; 95% confidence interval, 0.89-0.99;
P = .041) and high pretreatment serum levels of immunoglobulin
M (IgM) anti-hepatitis B core antigen (HBc) (odds ratio, 4.52;
95% confidence interval, 1.63-12.5; P = .004). Liver disease
progressed in none of the sustained responders but in 16 with
treatment failure (0% vs. 22%, P = .002); hepatocellular
carcinoma (HCC) developed with similar frequency in both groups
(7%). Overall, estimated 8-year complication-free survival was
longer for the 30 sustained responders than the 71 patients with
treatment failure (90% vs. 60%, P < .001), but 8-year
patient survival was similar in the 2 groups (100% and 90%). Short
complication-free survival was predicted by failure to respond
to interferon (hazard ratio, 7.8; 95% confidence interval, 1.8-34.0;
P = .006) and high scores for liver fibrosis (hazard ratio,
1.71; 95% confidence interval, 1.17-2.50; P = .005). In
conclusion, 24 months of treatment with interferon alfa 2b led
to sustained disease suppression in a significant proportion of
patients with HBeAg-negative chronic hepatitis B. (HEPATOLOGY
2003;37:756-763.) ![]()
Inhibition of hepatitis B virus expression and replication
by RNA interference
Amir Shlomai, Yosef Shaul
RNA interference (RNAi) is the process of sequence-specific gene
silencing, initiated by double-stranded RNA (dsRNA) that is homologous
in sequence to the target gene. Because it has been shown that
RNAi can be accomplished in cultured mammalian cells by introducing
small interfering RNAs (siRNAs), much effort has been invested
in exploiting this phenomenon for experimental and therapeutic
means. In this study, we present a series of experiments showing
a significant reduction in hepatitis B virus (HBV) transcripts
and proteins in cell culture, as well as in the viral replicative
forms, induced by siRNA-producing vectors. The antiviral effect
is sequence-specific and does not depend on active viral replication.
In conclusion, our data suggest that RNAi may provide a powerful
therapeutic tool, acting both on replication-competent and on
replication-incompetent HBV. (HEPATOLOGY 2003;37:764-770.) ![]()
Role of type 1 versus type 2 immune responses in liver during
the onset of chronic woodchuck hepatitis virus infection
Yun Wang, Stephan Menne, James R. Jacob, Bud C. Tennant, John
L. Gerin, Paul J. Cote
Immune response messenger RNAs (mRNA) were compared in liver during
self-limited (resolved) and chronic neonatal woodchuck hepatitis
virus (WHV) infection. At week 14 postinfection (mid-acute phase),
mRNAs for leukocyte markers (CD3, CD4, CD8), type 1 cytokines
and related transcription factors (IFN-, TNF-, STAT4, T-bet),
and IL-10 were increased in livers from resolving infections,
but mRNAs of other type 1 (IL-2) and type 2 (IL-4, STAT6, and
GATA3 markers remained at baseline levels. Increased coexpression
of IFN- and TNF- mRNAs correlated in most cases with lower levels
of intrahepatic WHV covalently closed circular DNA (cccDNA). At
the same time point postinfection, livers from woodchucks that
eventually progressed to chronic infection had baseline or slightly
elevated levels of CD and type 1 mRNAs, which were significantly
lower (or elevated less frequently) compared with resolving woodchucks.
Earlier, at week 8, there were no differences between the two
outcome settings. During these early time points and at a later
stage in chronic infection (15 months), type 2 mRNAs in carrier
liver remained at baseline levels or, when elevated, were never
in excess of those in resolving woodchucks. In conclusion, the
onset and maintenance of neonatal chronic WHV infection are not
associated with antagonistic type 2 immunoregulation of type 1
responses in liver. Accordingly, chronicity develops in association
with a primary deficiency in the intrahepatic CD responses, especially
involving CD8+ T lymphocytes, and in both extracellular (cytokine)
and intracellular (transcriptional) type 1 response mediators.
This has relevant implications for future treatment of chronic
hepatitis B virus (HBV) infection in humans. (HEPATOLOGY 2003;37:771-780.)
![]()
Primary lymphoma of the liver: Clinical-pathological features
and relationship with HCV infection in French patients (*Human
Study*)
Jean-Pierre Bronowicki, Catherine Bineau, Pierre Feugier, Olivier
Hermine, Nicole Brousse, Frédéric Oberti, Marie-Christine
Rousselet, Sébastien Dharancy, Philippe Gaulard, Jean-François
Flejou, Dominique Cazals-Hatem, Eric Labouyrie
Primary lymphoma of the liver (PLL) is rare. In some cases, the
hepatic lymphoma has been diagnosed in patients who were infected
by the hepatitis C virus (HCV). It has been suggested that HCV
plays a role in the pathogenesis of lymphoma. The aim of our multicentric
retrospective study was to assess the characteristics of PLL and
to determine the prevalence of HCV infection in PLL. Thirty-one
immunocompetent patients (anti-human immunodeficiency virus, anti-human
T-cell leukemia/lymphoma virus negative, no history of allograft)
with PLL fulfilled the entire selection criteria. The liver biopsy
specimens were reassessed by the same pathologist. The non-Hodgkin's
lymphomas were classified according to the World Health Organization
classification. Blood samples were tested in 28 patients for antibodies
to HCV, and HCV RNA was detected by reverse transcription polymerase
chain reaction. In the majority of cases, the clinical, biologic,
and radiologic data were nonspecific. Twenty-seven of 31 patients
presented a B-cell lymphoma corresponding to the centroblastic
morphologic variant of a diffuse, large B-cell lymphoma (22 cases),
a Burkitt's lymphoma (1 case), an extranodal marginal zone B-cell
lymphoma of mucosa-associated lymphoid tissue type (3 cases),
and unclassified, small B-cell lymphoma (1 case). The 4 other
cases were T-cell lymphomas. The prevalence of HCV infection was
21% (6 of 28 cases). All of these patients were positive for HCV
RNA by polymerase chain reaction in blood. Most of the HCV-infected
patients presented a high-grade, B-cell type lymphoma. In conclusion,
our study confirms the rarity of PLL and demonstrates an increased
prevalence of HCV infection. (HEPATOLOGY 2003;37:781-787). ![]()
The relationship of in vivo 31P MR spectroscopy
to histology in chronic hepatitis C (*Human Study*)
Adrian K. P. Lim, Nayna Patel, Gavin Hamilton, Joseph V. Hajnal,
Robert D. Goldin, Simon D. Taylor-Robinson
Liver biopsy remains the gold standard for characterizing diffuse
liver disease and is associated with significant morbidity and,
rarely, mortality. Our aim was to investigate whether a noninvasive
technique, in vivo phosphorus 31 (31P)-magnetic resonance
spectroscopy (MRS), could be used to assess the severity of hepatitis
C virus (HCV)-related liver disease. Fifteen healthy controls
and 48 patients with biopsy-proven HCV-related liver disease were
studied prospectively. Based on their histologic fibrosis (F)
and necroinflammatory (NI) scores, patients were divided into
mild hepatitis (F 2/6, NI 3/18), moderate/severe hepatitis (3
F < 6 or NI 4/18), and cirrhosis (F = 6/6). Hepatic 31P MR
spectra were obtained using a 1.5-T spectroscopy system. Quantitation
of the 31P signals was performed in the time domain using the
Advanced MAgnetic RESonance algorithm. There was a monotonic increase
in the mean ± 1 standard error phosphomonoester (PME) to
phosphodiester (PDE) ratios for the control, mild disease, moderate
disease, and cirrhosis groups: 0.15 ± 0.01, 0.18 ±
0.02, 0.25 ± 0.02, 0.38 ± 0.04, respectively (ANOVA,
P < .001). An 80% sensitivity and specificity was achieved
when using a PME/PDE ratio less than or equal to 0.2 to denote
mild hepatitis and a corresponding ratio greater than or equal
to 0.3 to denote cirrhosis. No other significant spectral changes
were observed. In conclusion, 31P MRS can separate mild from moderate
disease and these 2 groups from cirrhosis. The ability to differentiate
these populations of patients has therapeutic implications and
31P MRS, in some situations, would not only complement a liver
biopsy but could replace it and be of particular value in assessing
disease progression. (HEPATOLOGY 2003;37:788-794.) ![]()
Racial differences in the relationship between hepatitis C
infection and iron stores (*Human Study*)
George N. Ioannou, Jason A. Dominitz, Noel S. Weiss, Patrick J.
Heagerty, Kris V. Kowdley
Black race and increased hepatic iron stores predict poor response
to interferon treatment for chronic hepatitis C virus (HCV) infection.
We tested the hypothesis that these 2 observations are linked
by investigating whether HCV-infected African-Americans have increased
iron stores relative to uninfected persons. Using data from the
third National Health and Nutrition Examination Survey (NHANES
III), we determined the risk of having increased iron stores,
defined as elevation of both serum ferritin and transferrin-iron
saturation (TS), in HCV-RNA-positive blacks (n = 100) and nonblacks
(n = 126) relative to HCV-RNA-negative blacks (n = 4,002) and
nonblacks (n = 10,943). HCV-positive blacks were 5.4 times (95%
CI, 1.2 to 24) more likely to have increased iron stores than
HCV-positive nonblacks. The proportion of HCV-positive blacks
who had increased iron stores was 16.4% among those with abnormal
liver enzymes and 2.8% among those with normal liver enzymes,
compared with only 0.6% among HCV-negative blacks. After adjustment
for age, alcohol intake, gender, menopausal status, education,
body mass index, and poverty index, HCV-positive blacks with abnormal
liver enzymes had an elevated risk of having increased iron stores
(odds ratio, 17.8; 95% CI, 5.1 to 63). In contrast, among persons
of other races, there was a much smaller difference in the proportion
of persons with increased iron stores between HCV-positive persons
with (3.4%) or without (1.4%) abnormal liver enzymes and HCV-negative
persons (0.9%). In conclusion, a greater proportion of blacks
than persons of other races respond to HCV infection with an increase
in iron stores. This finding may partly explain the reduced response
of HCV-positive African-Americans to antiviral treatment. (HEPATOLOGY
2003;37:795-801.) ![]()
Hepatitis C virus infection in the general population: A community-based
study in West Bengal, India (*Human Study*)
Abhijit Chowdhury, Amal Santra, Susmita Chaudhuri, Gopal Krishna
Dhali, Sujit Chaudhuri, Satya Gopal Maity, Trailokya Nath Naik,
Sujit Kumar Bhattacharya, Debendra Nath Guha Mazumder
Limited information is available about the prevalence and genotype
distribution of hepatitis C virus (HCV) in the general population
of India. A community-based epidemiologic study was carried out
in a district in West Bengal, India. By a 1:3 sampling method,
3,579 individuals were preselected from 10,737 inhabitants of
9 villages of the district, of whom 2,973 (83.1%) agreed to participate.
Twenty-six subjects (0.87%) were HCV antibody positive. The prevalence
increased from 0.31% in subjects <10 years of age to 1.85%
in those 60 years. No difference in prevalence between men and
women was observed. Serum alanine aminotransferase (ALT) levels
were elevated in 30.8% (8 of 26) of anti-HCV-positive subjects
compared with 3.2% (94 of 2,947) anti-HCV-negative subjects (P
< .001). HCV RNA was detectable in 80.8% (95% CI, 65.6%-95.91%)
of the anti-HCV-positive subjects by reverse transcription-primed
polymerase chain reaction (RT-PCR). The participants were HCV
types 1b in 2 (9.5%), 3a in 8 (38.1%), 3b in 6 (28.6%), and unclassified
in 5 (23.8%). Nucleotide sequencing and phylogenetic analysis
assigned the unclassified type to genotype 3e. In conclusion,
this study provides general population-based estimates of HCV
prevalence, including genotypes, from a South Asian country. Although
the prevalence of HCV infection in this population was lower than
that reported from industrialized countries of the west, the total
reservoir of infection is significant and calls for public health
measures, including health education to limit the magnitude of
the problem.(HEPATOLOGY 2003;37:802-809.) ![]()
Liver Biology and Pathobiology
Nitric oxide-mediated cytoprotection of hepatocytes from
glucose deprivation-induced cytotoxicity: Involvement of heme
oxygenase-1
Byung-Min Choi, Hyun-Ock Pae, Young-Myeong Kim, Hun-Taeg Chung
Heme oxygenase-1 (HO-1) is the rate-limiting enzyme in heme catabolism,
which leads to the generation of carbon monoxide (CO), biliverdin,
and free iron. One of 3 mammalian HO isoforms, HO-1, is a stress-responsive
protein and known to modulate such cellular functions as cytokine
production, cell proliferation, and apoptosis to protect organs
and tissues from acute injury. Although nitric oxide (NO)-mediated
cytoprotective effects against cytotoxicity induced by glucose
deprivation have been well recognized, the underlying mechanisms
remain to be elucidated. Thus, we investigate the involvement
of HO-1 in the cytoprotective effects of NO. Deprivation of glucose
markedly reduced the viability of BNL CL.2 cells and primary rat
hepatocytes. Pretreatment with NO donor, sodium nitroprusside
(SNP), protected hepatocytes from glucose deprivation-induced
cytotoxicity; zinc protoporphyrin (ZnPP) IX, an inhibitor of HO,
was found to block the SNP-induced cytoprotection. SNP increased
the induction of HO-1 protein as well as its activity in hepatocytes.
A cytoprotective effect comparable to SNP was observed when the
cells were transfected with HO-1 gene or preincubated with another
HO-1 inducer, hemin. Additional experiments revealed the involvement
of CO in the cytoprotective effect of SNP/HO-1 in BNL CL.2 cells.
CO mediated cytoprotective effect through suppression of ERK MAPK
activation. In conclusion, our results show that SNP protects
hepatocytes from glucose deprivation-induced cytotoxicity through
up-regulation of HO-1. Thus, HO-1 might be an important cellular
target of NO donor with clinical implications for the prevention
of acute liver injury in several pathological conditions. (HEPATOLOGY
2003;37:810-823.) ![]()
c-Jun-N-terminal kinase drives cyclin D1 expression and proliferation
during liver regeneration
Robert F. Schwabe, Cynthia A. Bradham, Tetsuya Uehara, Etsuro
Hatano, Brydon L. Bennett, Robert Schoonhoven, David A. Brenner
The c-Jun-N-terminal kinase (JNK) pathway is strongly activated
after partial hepatectomy (PH), but its role in hepatocyte proliferation
is not known. In this study, JNK activity was blocked with the
small molecule inhibitor JNK SP600125 in vivo and in
vitro as shown by a reduction of c-Jun phosphorylation, AP-1
DNA binding activity, and c-jun messenger RNA (mRNA) expression.
SP600125 inhibited proliferating cell nuclear antigen (PCNA) expression,
cyclin D1 mRNA and protein expression and reduced mitotic figures
after PH. Survival was reduced significantly 3 days after PH in
SP600125-treated versus vehicle-treated rats (3 of 11 vs. 8 of
9, P < .01). In epidermal growth factor (EGF)-treated
primary cultures of rat hepatocytes, SP600125 decreased 3H-thymidine
uptake, cyclin D1 mRNA and protein expression, and inhibited the
EGF-induced transcription of a cyclin D1 promoter-driven reporter
gene. The defective regeneration and the decreased survival in
SP600125-treated rats did not result from a major increase in
apoptosis as shown by normal levels of caspase 3 activity and
only slight increases in apoptotic figures. In conclusion, our
data show that JNK drives G0 to G1 transition in hepatocytes and
that cyclin D1 is a downstream target of the JNK pathway during
liver regeneration. (HEPATOLOGY 2003;37:824-832.) ![]()
p18(INK4c) collaborates with other CDK-inhibitory proteins
in the regenerating liver
Tom Luedde, Maria E. Rodriguez, Frank Tacke, Yue Xiong, David
A. Brenner, Christian Trautwein
p18(INK4c) belongs to the family of cyclin-dependent kinase inhibitory
proteins that target the cyclin-dependent kinases and inhibit
their catalytic activity. The role of p18(INK4c) for cell cycle
progression in vivo is characterized poorly. Therefore,
we studied the expression and physiologic relevance of p18 in
quiescent and proliferating hepatocytes during liver regeneration.
For our analysis we used single- (p18[INK4c], p27[KIP1], p21[CIP1/WAF1]),
and double-mutant (p18/p21, p18/p27) mice. p18 expression was
found in quiescent hepatocytes and a slight up-regulation was
evident after partial hepatectomy (PH). p18 knockout animals showed
normal cell cycle progression after PH. However, when p18/p21
and p18/p27 double-mutant mice were used, differences in cell
cycle progression were evident compared with wild-type (wt) and
single knockout animals. In p18/p21 knockout animals, the G1 phase
was shortened as evidenced by an earlier onset of cyclin D and
proliferating cell nuclear antigen (PCNA) expression and cyclin-dependent
kinase (CDK) activation after PH. In contrast, in p18/p27 knockout
animals, the G1 phase was unchanged, but the amount of proliferating
hepatocytes (5-bromo-2´-deoxyuridine [BrdU] and PCNA positive)
48 hours after PH was elevated. In conclusion, our results suggest
that p18 is involved in cell cycle progression after PH. Additionally
we provide evidence that timing and strength of DNA synthesis
in hepatocytes after PH is regulated tightly through the collaboration
of different cell cycle inhibitors. (HEPATOLOGY 2003;37:833-841.)
![]()
Changes in mitochondrial adenine nucleotides and in permeability
transition in two models of rat liver regeneration
Rolando Hernández-Muñoz, Lourdes Sánchez-Sevilla,
Alejandro Martínez-Gómez, Myrna A. R. Dent
Although enhanced phosphorylative activity can be a requisite
for later DNA synthesis during liver regeneration (LR), mitochondrial
generation of reactive oxygen species could lead to altered mitochondrial
membrane permeability during the prereplicative phase of LR. Therefore,
the role of mitochondrial permeability transition (MPT) was evaluated
during rat LR, induced by either partial hepatectomy (PH) or after
CCl4 administration. Parameters indicative of mitochondrial function
and membrane potentials, those of oxidative stress, and in
vivo changes of the intramitochondrial pool of adenine nucleotides
were determined. Twelve hours after PH, mitochondrial oxidative
and phosphorylative activities and adenosine diphosphate (ADP)
content were increased, reaching a maximal peak at 24 hours after
surgery (maximal DNA synthesis). Parameters suggestive of oxidant
stress were enhanced, but mitochondrial volume and membrane electrical
potential remained unaltered. Interestingly, moderate mitochondrial
swelling and depolarization were found at later post-PH times
(72 hours). In CCl4-treated animals, it was found that an active
liver cell necrosis delayed mitotic activity and mitochondrial
uncoupled respiration. Starting 12 hours after CCl4 intoxication,
a drastic increase of inorganic phosphate occurred within swollen
and strongly depolarized mitochondria, suggesting changes in the
MPT. Despite expression of messenger RNA (mRNA) for mitochondrial
transcription, factor A showed a similar time course in both experimental
models. The so-called augmenter liver regeneration was found significantly
elevated only in PH rats. In conclusion, onset of MPT could be
associated with cell necrosis and inflammation after CCl4 treatment,
whereas this mitochondrial event could constitute a putative effector
mechanism, through which growth or inflammatory factors inhibiting
cell proliferation could initiate LR termination. (HEPATOLOGY
2003;37:842-851.) ![]()
Homozygous deletion scanning in hepatobiliary tumor cell lines
reveals alternative pathways for liver carcinogenesis
Pascal Pineau, Agnès Marchio, Seishi Nagamori, Shuichi
Seki, Pierre Tiollais, Anne Dejean
Despite high rates of loss of heterozygosity affecting various
chromosomes, the number of tumor suppressor genes (TSGs) found
to be consistently involved in primary liver cancer is low. In
the past decade, characterization of homozygous deletions (HDs)
in tumors has become instrumental to identify new TSGs or to reveal
the influence of a particular TSG on the development of a specific
tumor type. We performed a detailed HD profiling at 238 critical
loci on a collection of 57 hepatobiliary tumor cell lines (hepatocellular,
cholangiocellular, and bile duct carcinomas, hepatoblastomas,
and immortalized hepatocytes). We identified HDs at 9 independent
loci, the analysis of which was extended to 17 additional hepatobiliary
tumor cell lines. In total, 34 homozygous losses involving 9 distinct
genes were detected in the 74 cell lines analyzed. Besides expected
deletions at the p16-INK4A/p14-ARF, FHIT, AXIN1, and p53 genes,
we detected HDs at the PTEN, NF2, STK11, BAX, and LRPDIT genes
that were formerly not known to be implicated in human liver tumorigenesis.
In conclusion, our data suggest that these genes may represent
novel liver tumor suppressive targets. Additional tumorigenic
pathways should be carefully considered in hepatocarcinogenesis.
(HEPATOLOGY 2003;37:852-861.) ![]()
Reduced hepatic tumor incidence in cyclin G1-deficient mice
Michael Rugaard Jensen, Valentina M. Factor, Anna Fantozzi, Kristian
Helin, Chang-Goo Huh, Snorri S. Thorgeirsson
Cyclin G1 is a transcriptional target of the tumor suppressor
p53, and its expression is increased after DNA damage. Recent
data show that cyclin G1 can regulate the levels of p53 by a mechanism
that involves dephosphorylation of Mdm2 by protein phosphatase
2A. To understand the biologic role of cyclin G1, we have generated
cyclin G1-deficient mice. In agreement with previous results,
we showed that these mice develop normally, and that proliferation
and induction of cellular senescence in cyclin G1-deficient mouse
embryo fibroblasts are indistinguishable from wild-type fibroblasts.
However, we found that the p53 levels in the cyclin G1-deficient
mice are 2-fold higher that in wild-type mice. Moreover, we showed
that treatment of mice with the alkylating agent 1,4-bis[N,N´-di(ethylene)-phosphamide]piperazine
(Dipin), followed by partial hepatectomy, decreased G1-S transition
in cyclin G1-null hepatocytes as compared with wild type. Finally,
we found a significant decrease in tumor incidence, mass, and
malignancy in both male and female cyclin G1-null mice after treatment
with the potent hepatocarcinogen N-diethylnitrosamine. Taken with
recent published data, our results suggest that cyclin G1, together
with Mdm2, constitute a part of a negative feedback system that
attenuates the activity of p53. In conclusion, our data suggest
that the decreased tumor susceptibility after loss of cyclin G1
function is caused by the increased tumor suppressor action of
p53. (HEPATOLOGY 2003;37:862-870.) ![]()
Microdissection-based allelotyping discriminates de novo tumor
from intrahepatic spread in hepatocellular carcinoma
Sydney D. Finkelstein, Wallis Marsh, Anthony J. Demetris, Patricia
A. Swalsky, Eizaburo Sasatomi, Andrew Bonham, Michael Subotin,
Igor Dvorchik
A total of 103 cases of hepatocellular carcinoma (HCC) arising
in native livers discovered at the time of transplantation underwent
allelic loss analysis. HCC mutational allelotyping targeted 10
genomic loci (1p, 3p, 5q, 7q, 8q, 9p, 10q, 17p, 17q, 18q) using
18 polymorphic microsatellite markers situated in proximity to
known tumor suppressor genes associated with human carcinogenesis.
Gene analysis was performed on microdissected tissue samples removed
from 4-µm thick histologic sections at specific topographic
sites selected on the basis of representative cellular characteristics.
Microdissection targets included largest tumor nodule at 2 locations
as well as up to 3 additional tumor nodules in each case. HCC
genotyping characteristics including mutational profile and cumulative
fractional allelic loss (FAL) were correlated with clinical and
pathologic features. Individual nodules of HCC showed 2 patterns
of mutational change: (1) essentially concordant mutational profiles
consistent with intrahepatic spread of tumor, or (2) discordant
mutational profiles consistent with independent primary cancer
formation. In 15 of 56 cases (27%) in which the HCC was in a multinodular,
bilobar form (T4), sufficient discordance in the allelic loss
profile enabled a more accurate T-stage classification with better
prediction of recurrence-free survival. In conclusion, microdissection
genotyping of HCC is an effective and objective means to (1) distinguish
between de novo HCC tumor formation versus intrahepatic
spread of cancer and to (2) improve on current methods for prediction
of tumor aggressiveness and recurrence-free survival after liver
transplantation. (HEPATOLOGY 2003;37:871-879.) ![]()
Influence of ursodeoxycholate-enriched diet on liver tumor
growth in HBV transgenic mice
Michele Barone, Eugenio Maiorano, Roberta Ladisa, Rosario Cuomo,
Antonia Pece, Pasquale Berloco, Maria Lucia Caruso, Anna Maria
Valentini, Achille Iolascon, Antonio Francavilla, Alfredo Di Leo,
Enzo Ierardi
Hepatitis B virus (HBV) transgenic mice (official designation,
Tg [Alb-1 HBV] Bri 44) invariably develop macroscopically evident
tumors within the 20th month of life. Sustained proliferative
activity seems to play an important role in the development of
these lesions. We previously showed that ursodeoxycholate (UDC)
stimulates hepatocyte proliferation in various experimental settings.
Herein, we tested the assumption that biological factors able
to further increase liver cell proliferation, such as UDC, could
accelerate tumor development in this animal model. For this study,
22 eight-week-old male transgenic mice were divided into 2 groups;
11 animals received a standard diet, and 11 received a UDC-enriched
diet. The 2 groups were further divided into 2 subgroups of 5
and 6 animals each and were sacrificed at 3 and 15 months of age,
respectively. These different times were chosen to exclude diet-related
toxicity (in 3-month-old mice) and evaluate tumor growth (in 15-month-old
mice). In addition, hepatocyte proliferation was assessed in all
animals. In 3-month-old mice receiving UDC, cholestatic and cytolytic
indices as well as liver histology were comparable to those in
controls. At 15 months, all UDC-treated mice showed large multinodular
tumors whereas only 33% of controls developed smaller uninodular
neoplasms. Hepatocyte proliferation was increased in all animals
receiving UDC compared with controls. In conclusion, the increase
in serum UDC (undetectable in mice fed a standard diet), in the
absence of any toxic effect on the liver, suggests the involvement
of this bile salt in the stimulation of hepatocyte proliferation
and tumor growth. (HEPATOLOGY 2003;37:880-886.) ![]()
Liver Failure and Liver Disease
A randomized controlled trial of ursodeoxycholic acid in
patients with alcohol-induced cirrhosis and jaundice (*Human Study*)
Gilles Pelletier, Dominique Roulot, Thierry Davion, Claude Masliah,
Xavier Causse, Frédéric Oberti, Jean-Jacques Raabe,
Claire Van Lemmens, Hélène Labadie, Lawrence Serfaty,
URSOMAF Group
The aim of our multicenter study was to assess the efficacy of
ursodeoxycholic acid (UDCA) on the survival of patients with alcohol-induced
cirrhosis and jaundice. We included patients with histologically
proven alcohol-induced cirrhosis and serum bilirubin >50 µmol/L.
After randomization, patients received either UDCA (13-15 mg/kg/d)
or a placebo for 6 months. Two hundred twenty-six patients (113
in each group) were included in 24 centers. There were 139 men
and 87 women, mean age of 50.3 years. Seventy-four percent had
associated alcohol-induced hepatitis, and 24% received a corticosteroid
therapy. At inclusion, the 2 groups were comparable for the main
clinical and biologic parameters, but serum bilirubin was higher
in the UDCA group than in the placebo group (163 µmol/L
vs. 145 µmol/L, P < .03). The percentage of patients
lost at follow-up or who resumed their alcoholism during the study
was comparable in the 2 groups. During the study, 55 patients
died, 35 in the UDCA group and 20 in the placebo group. In the
intention to treat analysis, the probability of survival at 6
months (Kaplan-Meier method) was lower in the UDCA than in the
P group (69% vs. 82%, respectively; P = .04, log-rank test).
After adjustment on the bilirubin level at entry (Cox model),
the independent predictive value of the treatment group did not
reach the statistical level (RR = 1.64, CI 0.85-2.85; P
= .077). In conclusion, UDCA administered at the dose recommended
in primary biliary cirrhosis has no beneficial effect on the 6-month
survival of patients with severe alcohol-induced cirrhosis. An
inappropriate dosage of UDCA cannot be excluded as an explanation
for the lack of therapeutic benefit.(HEPATOLOGY 2003;37:887-892.)
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Rapid diagnosis of spontaneous bacterial peritonitis by use
of reagent strips (*Human Study*)
José Castellote, Carmen López, Joan Gornals, Gemma
Tremosa, Eva Rodríguez Fariña, Carmen Baliellas,
Alicia Domingo, Xavier Xiol
We studied the use of reagent strips for diagnosis of spontaneous
bacterial peritonitis (SBP) in cirrhotic patients with ascites.
A reagent strip for leukocyte esterase designed for the testing
of urine with a colorimetric 5-grade scale (0 to 4) was used to
evaluate ascitic fluid in 228 nonselected paracentesis performed
in 128 cirrhotic patients. We diagnosed 52 SBP and 5 secondary
bacterial peritonitis by means of polymorphonuclear cell count
and classical criteria. When we considered positive a reagent
strip result of 3 or 4, sensitivity was 89% (51 of 57), specificity
was 99% (170 of 171), and positive predictive value was 98%. When
we considered positive a reagent strip result of 2 or more, sensitivity
was 96% (55 of 57), specificity was 89% (152 of 171), and negative
predictive value was 99%. In conclusion, the use of reagent strips
is a rapid, easy to use, and inexpensive tool for diagnosis of
ascitic fluid infection. A positive result should be an indication
for empirical antibiotic therapy, and a negative result may be
useful as a screening test to exclude SBP. (HEPATOLOGY 2003;37:893-896.)
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Spontaneous bacterial peritonitis in asymptomatic outpatients
with cirrhotic ascites (*Human Study*)
Luke T. Evans, W. Ray Kim, John J. Poterucha, Patrick S. Kamath
The prevalence and natural history of spontaneous bacterial peritonitis
in asymptomatic patients with ascites secondary to cirrhosis is
unknown. From a prospectively recorded database, we reviewed the
clinical and laboratory features of all outpatients with cirrhotic
ascites undergoing paracentesis between July 1994 and December
2000. The prevalence of spontaneous bacterial peritonitis in the
population of 427 cirrhotic outpatients as defined by neutrocytic
ascites (absolute neutrophil count 250 cells/mm3) was 3.5%. Of
the 15 patients with neutrocytic ascites, 6 were culture positive
(1.4%) and 9 culture negative (2.1%). Eight other patients (1.9%)
had bacterascites. The organisms cultured from ascitic fluid in
these asymptomatic patients with culture positive neutrocytic
ascites and bacterascites were predominantly gram positive. No
patient developed hepatorenal syndrome, and 1-year survival of
67% was better than historical data from hospitalized patients
with spontaneous bacterial peritonitis. Moreover, patients who
did not receive antibiotics for neutrocytic ascites fared no worse
than patients who did receive antibiotics. In conclusion, spontaneous
bacterial peritonitis in outpatients with cirrhotic ascites is
less frequent, occurs in patients with less advanced liver disease,
and may have a better outcome than its counterpart in hospitalized
patients. In addition, the organisms cultured from ascitic fluid
in outpatients are predominantly gram positive. A reassessment
of diagnostic criteria for spontaneous bacterial peritonitis in
outpatients may be required. (HEPATOLOGY 2003;37:897-901.) ![]()
Hemodynamic response to pharmacological treatment of portal
hypertension and long-term prognosis of cirrhosis (*Human
Study*)
Juan G. Abraldes, Ilaria Tarantino, Juan Turnes, Juan Carlos Garcia-Pagan,
Juan Rodés, Jaime Bosch
In cirrhotic patients under pharmacologic treatment for portal
hypertension, a reduction in hepatic venous pressure gradient
(HVPG) of 20% of baseline or to 12 mm Hg markedly reduces the
risk of variceal rebleeding. This study was aimed at evaluating
whether these hemodynamic targets also prevent other complications
of portal hypertension and improve long-term survival. One hundred
five cirrhotic patients included in prospective trials for the
prevention of variceal rebleeding were studied. Seventy-three
of the patients had 2 separate HVPG measurements, at baseline
and under pharmacologic therapy with propranolol ± isosorbide
mononitrate. Patients were followed for up to 8 years. Survival
and risk of developing portal hypertension-related complications
were compared between responders and nonresponders. Twenty-eight
patients showed a reduction of HVPG 20% of baseline or to 12 mm
Hg (responders), and 45 patients were nonresponders. Nonresponders
had a significantly greater risk of developing variceal rebleeding
(P = .013), ascites (P = .025), spontaneous bacterial
peritonitis (P = .003), hepatorenal syndrome (P
= .026), and hepatic encephalopathy (P = .024) than responders.
Eight-year cumulative probability of survival was significantly
lower in nonresponders than in responders (52% vs. 95%, respectively,
P = .003). At multivariate analysis, being a nonresponder
was independently associated with the risk of developing rebleeding,
ascites, spontaneous bacterial peritonitis, and lower survival.
In conclusion, in cirrhotic patients receiving pharmacologic treatment
for prevention of variceal rebleeding, a decrease in HVPG 20%
or to 12 mm Hg is associated with a marked reduction in the long-term
risk of developing complications of portal hypertension and with
improved survival. (HEPATOLOGY 2003;37:902-908.) ![]()
Dietary habits and their relations to insulin resistance and
postprandial lipemia in nonalcoholic steatohepatitis (*Human
Study*)
Giovanni Musso, Roberto Gambino, Franco De Michieli, Maurizio
Cassader, Mario Rizzetto, Marilena Durazzo, Emanuela Fagà,
Barbara Silli, Gianfranco Pagano
The relations of dietary habits to insulin sensitivity and postprandial
triglyceride metabolism were evaluated in 25 patients with nonalcoholic
steatohepatitis (NASH) and 25 age-, body mass index (BMI)-, and
gender-matched healthy controls. After a 7-day alimentary record,
they underwent a standard oral glucose tolerance test (OGTT),
and the insulin sensitivity index (ISI) was calculated from the
OGTT; an oral fat load test was also performed in 15 patients
and 15 controls. The dietary intake of NASH patients was richer
in saturated fat (13.7% ± 3.1% vs. 10.0% ± 2.1%
total kcal, respectively, P = .0001) and in cholesterol
(506 ± 108 vs. 405 ± 111 mg/d, respectively, P
= .002) and was poorer in polyunsaturated fat (10.0% ±
3.5% vs. 14.5% ± 4.0% total fat, respectively, P
= .0001), fiber (12.9 ± 4.1 vs. 23.2 ± 7.8 g/d,
respectively, P = .000), and antioxidant vitamins C (84.3
± 43.1 vs. 144.2 ± 63.1 mg/d, respectively, P
= .0001) and E (5.4 ± 1.9 vs. 8.7 ± 2.9 mg/d, respectively,
P = .0001). The ISI was significantly lower in NASH patients
than in controls. Postprandial total and very low density lipoproteins
triglyceride at +4 hours and +6 hours, triglyceride area under
the curve, and incremental triglyceride area under the curve were
higher in NASH compared with controls. Saturated fat intake correlated
with ISI, with the different features of the metabolic syndrome,
and with the postprandial rise of triglyceride. Postprandial apolipoprotein
(Apo) B48 and ApoB100 responses in NASH were flat and strikingly
dissociated from the triglyceride response, suggesting a defect
in ApoB secretion. In conclusion, dietary habits may promote steatohepatitis
directly by modulating hepatic triglyceride accumulation and antioxidant
activity as well as indirectly by affecting insulin sensitivity
and postprandial triglyceride metabolism. Our findings provide
further rationale for more specific alimentary interventions,
particularly in nonobese, nondiabetic normolipidemic NASH patients.
(HEPATOLOGY 2003;37:909-916.) ![]()
Nonalcoholic fatty liver, steatohepatitis, and the metabolic
syndrome
Giulio Marchesini, Elisabetta Bugianesi, Gabriele Forlani, Fernanda
Cerrelli, Marco Lenzi, Rita Manini, Stefania Natale, Ester Vanni,
Nicola Villanova, Nazario Melchionda, Mario Rizzetto
Nonalcoholic fatty liver disease (NAFLD) has been associated with
the insulin-resistance syndrome, at present defined as the metabolic
syndrome, whose limits were recently set. We assessed the prevalence
of the metabolic syndrome in 304 consecutive NAFLD patients without
overt diabetes, on the basis of 3 or more criteria out of 5 defined
by the U.S. National Institutes of Health (waist circumference,
glucose, high-density lipoprotein [HDL]-cholesterol, triglycerides,
and arterial pressure). The prevalence of the metabolic syndrome
increased with increasing body mass index, from 18% in normal-weight
subjects to 67% in obesity. Insulin resistance (Homeostasis Model
Assessment method) was significantly associated with the metabolic
syndrome (odds ratio [OR], 2.5; 95% CI, 1.5-4.2; P <
.001). Liver biopsy was available in 163 cases (54%). A total
of 120 patients (73.6%) were classified as having nonalcoholic
steatohepatitis (NASH); 88% of them had a metabolic syndrome (vs.
53% of patients with pure fatty liver; P < .0001). Logistic
regression analysis confirmed that the presence of metabolic syndrome
carried a high risk of NASH among NAFLD subjects (OR, 3.2; 95%
CI, 1.2-8.9; P = .026) after correction for sex, age, and
body mass. In particular, the syndrome was associated with a high
risk of severe fibrosis (OR, 3.5; 95% CI, 1.1-11.2; P =
.032). In conclusion, the presence of multiple metabolic disorders
is associated with a potentially progressive, severe liver disease.
The increasing prevalence of obesity, coupled with diabetes, dyslipidemia,
hypertension, and ultimately the metabolic syndrome puts a very
large population at risk of forthcoming liver failure in the next
decades. (HEPATOLOGY 2003;37:917-923.) ![]()
Cytochrome P450 2E1 genotype and the susceptibility to antituberculosis
drug-induced hepatitis (*Human Study*)
Yi-Shin Huang, Herng-Der Chern, Wei-Juin Su, Jaw-Ching Wu, Shi-Chuan
Chang, Chi-Huei Chiang, Full-Young Chang, Shou-Dong Lee
Most cases with antituberculosis drug-induced hepatitis have been
attributed to isoniazid. Isoniazid is metabolized by hepatic N-acetyltransferase
(NAT) and cytochrome P450 2E1 (CYP2E1) to form hepatotoxins. However,
the role of CYP2E1 in this hepatotoxicity has not yet been reported.
The aim of this study was to evaluate whether the polymorphism
of the CYP2E1 gene is associated with antituberculosis
drug-induced hepatitis. A total of 318 tuberculosis patients who
received antituberculosis treatment were followed prospectively.
Their CYP2E1 and NAT2 genotypes were determined
using a polymerase chain reaction with restriction fragment length
polymorphism method. Twenty-one healthy volunteers were recruited
for CYP2E1 phenotype study using a chlorzoxazone test. Forty-nine
(15.4%) patients were diagnosed to have drug-induced hepatotoxicity.
Patients with homozygous wild genotype CYP2E1 c1/c1 had
a higher risk of hepatotoxicity (20.0%; odds ratio [OR], 2.52)
than those with mutant allele c2 (CYP2E1 c1/c2 or c2/c2,
9.0%, P = .009). If CYP2E1 c1/c2 or c2/c2 genotype
combined with rapid acetylator status was regarded as the reference
group, the risk of hepatotoxicity increased from 3.94 for CYP2E1
c1/c1 with rapid acetylator status to 7.43 for CYP2E1 c1/c1
with slow acetylator status. After adjustment for acetylator status
and age, the CYP2E1 c1/c1 genotype remained an independent
risk factor for hepatotoxicity (OR, 2.38; P = .017). Furthermore,
under the administration of isoniazid, the volunteers with CYP2E1
c1/c1 genotype had higher CYP2E1 activity than those with other
genotypes had and, hence, might produce more hepatotoxins. In
conclusion, CYP 2E1 genetic polymorphism may be associated
with susceptibility to antituberculosis drug-induced hepatitis.
(HEPATOLOGY 2003;37:924-930.) ![]()
Induced hyperammonemia alters neuropsychology, brain MR spectroscopy
and magnetization transfer in cirrhosis (*Human Study*)
Sherzad Balata, Steven W. M. Olde Damink, Karen Ferguson, Ian
Marshall, Peter C. Hayes, Nicolaas E. P. Deutz, Roger Williams,
Joanna Wardlaw, Rajiv Jalan
Hyperammonemia is a universal finding after gastrointestinal hemorrhage
in cirrhosis. We administered an oral amino acid solution mimicking
the hemoglobin molecule to examine neuropsychological changes,
brain glutamine levels, and brain magnetization transfer ratio
(MTR). Forty-eight metabolically stable patients with cirrhosis
and no evidence of "overt" hepatic encephalopathy (HE)
were randomized to receive 75 g of amino acid solution or placebo;
measurements were performed before and 4 hours after administration.
Neuropsychological tests included the Trails B Test, Digit Symbol
Substitution Test, memory subtest of the Randt battery, and reaction
time. Plasma was collected for ammonia and amino acid measurements,
and brain metabolism was studied using proton magnetic resonance
(MR) spectroscopy in the first 16 randomized patients. In 7 other
patients, MTR was measured. A significant increase in ammonia
levels was observed in the amino acid group (amino acid group,
76 ± 7.3 to 121 ± 6.4 µmol/L; placebo, 83
± 3.3 to 78 ± 2.9 µmol/L; P < .001).
Neuropsychological function improved significantly in the placebo
group, but no significant change in neuropsychological function
was observed in the amino acid group. Brain glutamate/glutamine
(Glx)/creatine (Cr) ratio increased significantly in the amino
acid group. MTR decreased significantly from 30 ±2.9 to
23 ± 4 (P < .01) after administration of the
amino acid solution. In conclusion, an improvement in neuropsychological
test results followed placebo, which was not observed in patients
administered the amino acid solution. Induced hyperammonemia resulted
in an increase in brain Glx/Cr ratio and a decrease in MTR, which
may indicate an increase in brain water as the operative mechanism.
(HEPATOLOGY 2003;37:931-939.) ![]()
The ABCs of biliary cholesterol secretion and their implication
for gallstone disease
Silvana Zanlungo, Juan Francisco Miquel, Attilio Rigotti, Flavio
Nervi
Two ATP-binding cassette (ABC) transporters, ABCG5 and ABCG8,
have been proposed to limit sterol absorption and to promote biliary
sterol excretion in humans. To test this hypothesis, a P1 clone
containing the human ABCG5 and ABCG8 genes was used to generate
transgenic mice. The transgenes were expressed primarily in the
liver and small intestine, mirroring the expression pattern of
the endogenous genes. Transgene expression only modestly affected
plasma and liver cholesterol levels but profoundly altered cholesterol
transport. The fractional absorption of dietary cholesterol was
reduced by about 50%, and biliary cholesterol levels were increased
more than fivefold. Fecal neutral sterol excretion was increased
three- to six-fold and hepatic cholesterol synthesis increased
two- to four-fold in the transgenic mice. No significant changes
in the pool size, composition, and fecal excretion of bile acids
were observed in the transgenic mice. Transgene expression attenuated
the increase in hepatic cholesterol content induced by consumption
of a high cholesterol diet. These results demonstrate that increased
expression of ABCG5 and ABCG8 selectively drives biliary neutral
sterol secretion and reduces intestinal cholesterol absorption,
leading to a selective increase in neutral sterol excretion and
a compensatory increase in cholesterol synthesis. ![]()
Regulation of apoptotic signaling pathways in hepatocytes in
vivo
Hartmut Jaeschke, Mary Lynn Bajt
The mitochondrial pathway is critical for the efficient execution
of death receptor-initiated apoptosis in certain cell types. Questions
remain as to why the mitochondria are required in that scenario.
We investigated the molecular events that determined the need
for the mitochondria by using an in vivo model of anti-Fas-induced
hepatocyte apoptosis. In wild-type mice, Fas stimulation resulted
in normal activation of caspase-3, with the generation of the
active p19-p12 complex. In bid-deficient mice, caspase-3
activation was arrested after the initial cleavage at Asp175.
This allowed the generation of the p12 small subunit, but the
p20 large subunit could not be further processed to the p19 subunit.
The p20-p12 complex generated by Fas stimulation in bid-deficient
hepatocytes was inactive, arresting the death program. Failure
of p20/p12 caspase-3 to mature and to exhibit activity was because
of the inhibition by the inhibitor-of-apoptosis proteins (IAPs),
such as XIAP, and also to a low caspase-8 activity. This block
could be overcome in wild-type mice by two mechanisms. Smac was
released from mitochondria early following Fas activation and
was competitively bound to the IAPs to reverse their effects.
XIAP could also be cleaved, and this occurred later and was likely
mediated by enhanced caspase activities. Both mechanisms were
dependent on Bid and thus were not operative in bid-deficient
hepatocytes. In conclusion, mitochondrial activation by Bid is
required for reversing the IAP inhibition through Smac release.
It is also required for the alternative activation of caspases
through cytochrome c release, as demonstrated previously.
Together, these events ensure a successful progression of the
death program initiated by the death receptor activation in the
hepatocyte. ![]()
Copyright © 2003 by the American Association for the
Study of Liver Diseases. All rights reserved.
Table of Contents for April
2003 · Volume 124 · Number 4
Rapid Communications
Methylene blue-aided chromoendoscopy for the detection of
intraepithelial neoplasia and colon cancer in ulcerative colitis
R. Kiesslich, J. Fritsch, M. Holtmann, H. H. Koehler, M. Stolte,
S. Kanzler, B. Nafe, M. Jung, P. R. Galle, M. F. Neurath
Background & Aims: Timely diagnosis of intraepithelial
neoplasias (IN) and colitis-associated colon carcinomas (CRC)
is crucially important for the treatment of ulcerative colitis
(UC). We performed a randomized, controlled trial to test whether
chromoendoscopy (CE) might facilitate early detection of IN and
CRC in UC. Methods: A total of 263 patients with long-standing
UC (8 years) were screened for potential inclusion in the study,
165 of whom were randomized at a 1:1 ratio to undergo conventional
colonoscopy or colonoscopy with CE using 0.1% methylene blue.
Five mucosal biopsy specimens were taken every 10 cm between the
rectum and cecum. Circumscript lesions in the colon were evaluated
according to a modified pit pattern classification. Results:
In the CE group, there was a significantly better correlation
between the endoscopic assessment of degree (P = 0.0002)
and extent (89% vs. 52%; P < 0.0001) of colonic inflammation
and the histopathologic findings compared with the conventional
colonoscopy group. More targeted biopsies were possible, and significantly
more IN were detected in the CE group (32 vs. 10; P = 0.003).
Using the modified pit pattern classification, both the sensitivity
and specificity for differentiation between non-neoplastic and
neoplastic lesions were 93%. Conclusions: Based on our
prospective randomized trial, CE permits more accurate diagnosis
of the extent and severity of the inflammatory activity in UC
compared with conventional colonoscopy. In addition, CE with methylene
blue is a novel tool for the early detection of IN and CRC in
patients with UC. These findings have important implications for
medical and surgical interventions. ![]()
Clinical-Alimentary Tract
Ursodeoxycholic acid as a chemopreventive agent in patients
with ulcerative colitis and primary sclerosing cholangitis
D. S. Pardi, E. V. Loftus, Jr, W. K. Kremers, J. Keach, K. D.
Lindor
Background & Aims: Ursodeoxycholic acid (UDCA) has
shown effectiveness as a colon cancer chemopreventive agent in
preclinical studies. In addition, a recent report suggests that
it also may decrease the risk for developing colorectal dysplasia
in patients with ulcerative colitis (UC) and primary sclerosing
cholangitis (PSC). We sought to evaluate the effect of UDCA on
colorectal neoplasia in a group of patients with UC and PSC enrolled
in a randomized, placebo-controlled trial. Methods: From
a prior, randomized, placebo-controlled trial of UDCA therapy
in PSC at our center, we followed-up patients with concomitant
UC to assess the effect of UDCA on the development of colorectal
dysplasia and cancer as compared with placebo. Results:
Fifty-two subjects were followed-up for a total of 355 person-years.
Those originally assigned to receive UDCA had a relative risk
of 0.26 for developing colorectal dysplasia or cancer (95% confidence
interval, 0.06-0.92; P = 0.034). Many of the patients originally
assigned to the placebo group eventually received open-label UDCA.
Assigning these patients to the UDCA group from the time they
began active therapy did not change the magnitude of the protective
effect (relative risk, 0.26; 95% confidence interval, 0.07-0.99;
P = 0.049). Conclusions: UDCA significantly decreases
the risk for developing colorectal dysplasia or cancer in patients
with UC and PSC. ![]()
Colonic fermentation influences lower esophageal sphincter
function in gastroesophageal reflux disease
T. Piche, S. B. des Varannes, S. Sacher-Huvelin, J. J. Holst,
J. C. Cuber, J. P. Galmiche
Background & Aims: Colonic fermentation of carbohydrates
is known to influence gastric and esophageal motility in healthy
subjects. This study investigated the effects of colonic fermentation
induced by oral administration of fructooligosaccharides (FOS)
in patients with gastroesophageal reflux disease (GERD). Methods:
In the cross-over design used in the study, 9 patients with symptomatic
GERD were administered a low-residue diet (i.e., 10 g fiber/day)
during 2, 7-day periods, receiving either 6.6 g of FOS or placebo
3 times daily after meals. Each period was separated by a wash
out of at least 3 weeks. On day 7, esophageal motility and pH
were recorded in fasting conditions and after a test meal containing
6.6 g of FOS or placebo. Breath hydrogen concentrations (reflecting
colonic fermentation) and plasma concentrations of glucagon-like
peptide 1 (GLP-1), peptide YY, and cholecystokinin were monitored.
Results: Compared with placebo, FOS led to a significant
increase in the number of transient lower esophageal sphincter
relaxations (TLESRs) and reflux episodes, esophageal acid exposure,
and the symptom score for GERD. The integrated plasma response
of GLP-1 was significantly higher after FOS than placebo. Conclusions:
Colonic fermentation of indigestible carbohydrates increases the
rate of TLESRs, the number of acid reflux episodes, and the symptoms
of GERD. Although different mechanisms are likely to be involved,
excess release of GLP-1 may account, at least in part, for these
effects. ![]()
Heterogeneity of symptom pattern, psychosocial factors, and
pathophysiological mechanisms in severe functional dyspepsia
B. Fischler, J. Tack, V. De Gucht, Z. Shkedy, P. Persoons, D.
Broekaert, G. Molenberghs, J. Janssens
Background & Aims: Categorization of functional dyspepsia
into subgroups is based on expert opinion according to (dominant)
symptoms or on underlying pathophysiological mechanisms. We used
an evidence-based approach to the determination of subtypes of
functional dyspepsia. Methods: Consecutive functional dyspepsia
patients were recruited from a tertiary referral center. The following
were performed: (1) exploratory (EFA) and confirmatory factor
analysis (CFA) of symptom patterns in a large group of patients
with functional dyspepsia; (2) external validation of these factors
by the determination of their association pattern with physio-
and psychopathological mechanisms, and with health-related quality
of life and sickness behavior; and (3) cluster analysis of their
distribution in this population. Results: Both EFA and
CFA do not support the existence of functional dyspepsia as a
homogeneous (unidimensional) condition. A 4-factor model is found
to be valid, with differential distribution within the patient
population according to cluster analysis. Factor 1 is characterized
by nausea, vomiting, early satiety, and weight loss and factor
2 by postprandial fullness and bloating. Both factor 1 and 2 are
associated with delayed emptying, but only factor 1 is associated
with younger age, female sex, and sickness behavior. Factor 3
is characterized by pain symptoms and associated with gastric
hypersensitivity and several psychosocial dimensions including
medically unexplained symptoms and health-related quality of life
dimensions. Factor 4, characterized by belching, is also associated
with hypersensitivity, but is unrelated to psychosocial dimensions.
Conclusions: In a tertiary care population, functional
dyspepsia is a heterogeneous condition characterized by 4 major
dimensions differentially associated with psychopathological and
physiopathological mechanisms. ![]()
Extracolonic findings at CT colonography: Evaluation of prevalence
and cost in a screening population
T. M. Gluecker, C. D. Johnson, L. A. Wilson, R. L. MacCarty, T.
J. Welch, D. J. Vanness, D. A. Ahlquist
Background & Aims: To assess the prevalence and spectrum
of extracolonic findings in a screening population undergoing
computed tomography colonography (CTC), and to evaluate the short-term
direct medical costs incurred from subsequent radiologic follow-up
evaluation. Methods: Six hundred and eighty-one asymptomatic
patients undergoing colonoscopy screening consented to a CTC examination.
Extracolonic CT findings were classified into high, medium, and
low importance. Clinical and radiologic follow-up, missed lesions,
and outcomes were assessed by chart review (time interval, 410-1513
days; median, 913 days). Short-term direct medical costs of radiologic
follow-up were determined based on Medicare 2002 reimbursement
rates. Results: Extracolonic findings were found commonly.
These were categorized as high clinical importance in 71 (10%)
individuals, as medium importance in 183 individuals (27%), and
as low importance in 341 individuals (50%). Subsequent medical
or surgical interventions resulted from these findings in 9 of
the 681 patients (1.3%). Costs of subsequent radiologic follow-up
studies were calculated as $23,380.59 (average added costs per
CTC examination $34.33). Conclusions: CTC commonly detects
extracolonic findings that can be considered clinically important
when applied to an asymptomatic screening population. Although
such incidental findings add benefit to the screening intervention,
moderate incremental costs are incurred based on additional radiologic
procedures generated during short-term follow-up. ![]()
Intravenous hydrocortisone premedication reduces antibodies
to infliximab in Crohn's disease: A randomized controlled trial
R. J. Farrell, M. Alsahli, Y.-T. Jeen, K. R. Falchuk, M. A. Peppercorn,
P. Michetti
Background & Aims: We assessed the relationship between
antibodies to infliximab (ATI) and the loss of response postinfliximab,
infusion reactions and, in a randomized trial, investigated whether
intravenous hydrocortisone premedication can reduce ATI. Methods:
Initially, we prospectively evaluated clinical response, adverse
events, and ATI levels in 53 consecutive patients with Crohn's
disease who received 199 infliximab (5 mg/kg) infusions. Subsequently,
80 patients with Crohn's disease were randomized to intravenous
hydrocortisone 200 mg or placebo immediately before their first
and subsequent infliximab infusions. The primary endpoint was
reduction in median ATI levels at week 16. Analysis was by intention
to treat. Results: Nineteen of our initial 53 patients
(36%) developed ATI, including all 7 patients with serious infusion
reactions (median ATI level, 19.6 µg/mL). Eleven of 15 patients
(73%) who lost their initial response were ATI positive compared
with none of 21 continuous responders, (8.9 vs. 0.7 µg/mL,
P < 0.0001). Administering a second infusion within
8 weeks of the first (OR, 0.13; 95% CI, 0.03-0.5; P = 0.0007)
or concurrent immunosuppressants (OR, 0.19; 95% CI, 0.04-1.03;
P = 0.007) significantly reduced ATI formation. In the
placebo-controlled trial, ATI levels were lower at week 16 among
hydrocortisone-treated patients (1.6 vs. 3.4 µg/mL, P
= 0.02), and 26% of hydrocortisone-treated patients developed
ATI compared with 42% of placebo-treated patients, P =
0.06. Conclusions: Loss of initial response and infusion
reactions post-infliximab is strongly related to ATI formation
and level. Administering a second infusion within 8 weeks of the
first and concurrent immunosuppressant therapy significantly reduce
ATI formation. Intravenous hydrocortisone premedication significantly
reduces ATI levels but does not eliminate ATI formation or infusion
reactions. ![]()
Clinical-Liver, Pancreas, and Biliary Tract
Epidemiologic and virologic characteristics of hepatitis B
virus genotype B having the recombination with genotype C
F. Sugauchi, E. Orito, T. Ichida, H. Kato, H. Sakugawa, S. Kakumu,
T. Ishida, A. Chutaputti, C.-L. Lai, R. G. Gish, R. Ueda, Y. Miyakawa,
M. Mizokami
Background & Aims: Hepatitis B virus (HBV) isolates
of genotype B (HBV/B) with or without the recombination with genotype
C over the precore region plus core gene have been reported. Methods:
All the 41 HBV/B isolates having the recombination with genotype
C (HBV/Ba) possessed the nucleotide 1838 of A in contrast to that
of G in all 29 of those without the recombination (HBV/Bj). Taking
advantage of this single nucleotide polymorphism, a restriction
fragment length polymorphism method was developed that distinguished
HBV/Ba from HBV/Bj. Results: HBV/Bj was detected in 90
of the 97 (93%) carriers of HBV/B from Japan, whereas HBV/Ba occurred
in all 177 carriers of HBV/B from other countries (China, 20;
Hong Kong, 45; Taiwan, 32; Thailand, 30; Vietnam, 30; and the
United States, 20 [all of an Asian ethnicity]). In a case-control
study, hepatitis B e antigen (HBeAg) and the double mutation in
the core promoter (T1762/A1764) were significantly more frequent
in 80 carriers each of HBV/Ba than HBV/Bj (35% vs. 18%, P
< 0.05 and 33% vs. 15%, P < 0.05, respectively).
Differences in the prevalence of HBeAg were more conspicuous between
the carriers of HBV/Bj and HBV/Ba older than 30 years (5 of 66
or 8% vs. 16 of 62 or 26%, P < 0.01). Conclusions:
HBV/B having the recombination with genotype C is frequent in
Asia, except in Japan, and HBeAg is more prevalent in carriers
of HBV/Ba than HBV/Bj. ![]()
Therapy of hyponatremia in cirrhosis with a vasopressin receptor
antagonist: A randomized double-blind multicenter trial
A. L. Gerbes, V. Gülberg, P. Ginès, G. Decaux, P.
Gross, H. Gandjini, J. Djian, VPA Study Group
Background & Aims: Dilutional hyponatremia is a frequent
complication of cirrhosis partly because of nonosmotic vasopressin
release. No effective therapy exists for this complication. Therefore,
we investigated the effects of VPA-985, an orally active vasopressin
V2 receptor antagonist, in patients with cirrhosis and dilutional
hyponatremia. Primary endpoint was normalization of serum sodium
(serum sodium 136 mmol/L). Methods: Sixty patients with
cirrhosis and dilutional hyponatremia were randomly assigned to
100 or 200 mg/day of VPA-985 or placebo in a double-blind study.
Treatment was given with fluid restriction (1000 mL/day) until
normalization of serum sodium or for 7 days. Results: Normalization
of serum sodium concentration was achieved in 27% and 50% of patients
in the VPA-985 100 mg/day and 200 mg/day groups, respectively,
but in none of the patients in the placebo group (P <
0.05 and P < 0.001, respectively). Treatment with VPA-985
was associated with a significant reduction in urine osmolality
and body weight. Thirst sensation increased significantly in the
VPA 200 mg group but not in the VPA 100 mg or placebo group. Serious
adverse events were similar among the 3 groups. Conclusions:
An orally active vasopressin receptor antagonist can correct hyponatremia
in patients with cirrhosis and ascites. This represents a novel
therapy of water retention in cirrhosis. ![]()
Methionine adenosyltransferase II subunit gene expression provides
a proliferative advantage in human hepatoma
M. L. Martínez-Chantar, E. R. García-Trevijano,
M. Ujue Latasa, A. Martín-Duce, P. Fortes, J. Caballería,
M. A. Avila, J. M. Mato
Background & Aims: Of the 2 genes (MAT1A, MAT2A)
encoding methionine adenosyltransferase, the enzyme that synthesizes
S-adenosylmethionine, MAT1A, is expressed in liver, whereas
MAT2A is expressed in extrahepatic tissues. In liver, MAT2A
expression associates with growth, dedifferentiation, and cancer.
Here, we identified the subunit as a regulator of proliferation
in human hepatoma cell lines. The subunit has been cloned and
shown to lower the Km of methionine adenosyltransferase II 2 (the
MAT2A product) for methionine and to render the enzyme
more susceptible to S-adenosylmethionine inhibition. Methods:
Methionine adenosyltransferase II 2 and subunit expression was
analyzed in human and rat liver and hepatoma cell lines and their
interaction studied in HuH7 cells. Subunit expression was up-
and down-regulated in human hepatoma cell lines and the effect
on DNA synthesis determined. Results: We found that subunit
is expressed in rat extrahepatic tissues but not in normal liver.
In human liver, subunit expression associates with cirrhosis and
hepatoma. Subunit is expressed in most (HepG2, PLC, and Hep3B)
but not all (HuH7) hepatoma cell lines. Transfection of subunit
reduced S-adenosylmethionine content and stimulated DNA synthesis
in HuH7 cells, whereas down-regulation of subunit expression diminished
DNA synthesis in HepG2. The interaction between methionine adenosyltransferase
II 2 and subunit was demonstrated in HuH7 cells. Conclusions:
Our findings indicate that subunit associates with cirrhosis and
cancer providing a proliferative advantage in hepatoma cells through
its interaction with methionine adenosyltransferase II 2 and down-regulation
of S-adenosylmethionine levels. ![]()
Up-regulation, nuclear import, and tumor growth stimulation
of the adhesion protein p120ctn in pancreatic cancer
J. Mayerle, H. Friess, M. W. Büchler, J. Schnekenburger,
F. U. Weiss, K.-P. Zimmer, W. Domschke, M. M. Lerch
Background & Aims: Cell adhesion proteins have been
implicated as tumor suppressors because they prevent malignant
cells from dissociating their cell contacts. We have studied the
role of p120ctn, a recently discovered member of the cadherin/catenin
family, in human pancreatic cancer. Methods: In 32 resection
specimens of pancreatic adenocarcinoma and 10 control samples
the expression of p120ctn was studied by Northern blot, immunocytochemistry,
and immunogold electron microscopy. Patient survival data, tumor
grading, and staging were correlated to the experimental results.
In PaTu 8889 T pancreatic cancer cells, p120ctn expression was
suppressed with 21-nucleotide small interfering RNA (siRNA) duplexes
and proliferation was determined by bromodeoxyuridine (BrdU) incorporation.
Results: In pancreatic cancer p120ctn messenger RNA (mRNA)
was increased 3- to 4-fold. Although p120ctn was localized exclusively
at cell contacts in controls it was found in the cytosol and nucleus
of pancreatic cancer cells. This redistribution correlated to
the degree of tumor dedifferentiation but was independent of tumor
stage. The mean survival of patients with predominant membrane
localization of p120ctn was 24 ± 7 (SEM) months vs. 9 ±
2 months for patients with predominant cytoplasmic p120ctn expression
(P < 0.05). Silencing of p120ctn with siRNA duplexes
reduced pancreatic cancer cell growth by 40%. Conclusions:
Up-regulation, cytoplasmic redistribution, and nuclear import
of p120ctn are associated with a more malignant phenotype of pancreatic
cancer. This study further represents conclusive evidence for
a direct involvement of p120ctn in malignant tumor cell proliferation.
Both p120ctn-defective tumor cell contacts and p120ctn-mediated
growth signals appear to contribute to the aggressive spread of
pancreatic cancer. ![]()
Basic-Alimentary Tract
Therapeutic effects of vasoactive intestinal peptide in the
trinitrobenzene sulfonic acid mice model of Crohn's disease
C. Abad, C. Martinez, M. G. Juarranz, A. Arranz, J. Leceta, M.
Delgado, R. P. Gomariz
Background & Aims: Crohn's disease (CD) is a chronic
debilitating disease of unknown etiology that is characterized
by severe inflammation of the colon. Vasoactive intestinal peptide
(VIP) has recently emerged as a promising candidate for treatment
of inflammatory Th1-driven diseases. We studied the effect of
VIP in trinitrobenzene sulfonic acid (TNBS)-induced colitis, which
has clinical and molecular features in common with CD. Methods:
A 3-mg enema of TNBS was given to BALB/c mice, and VIP (1 nmol)
was given either as a single dose at 12 hours or every other day.
Weight loss, histopathology, and chemokine and cytokine levels
in serum and colon extracts were assessed. VIP was also tested
given 5 days after the onset of TNBS-induced colitis, and its
effect was analyzed given a second dose of TNBS. Results:
Treatment with VIP reduced the clinical and histopathologic severity
of TNBS-induced colitis, abrogating body weight loss, diarrhea,
and macroscopic and microscopic intestinal inflammation. The therapeutic
effects of VIP were associated with down-regulation of both inflammatory
and Th1-driven autoimmune responses, including tumor necrosis
factor , interleukin 1, and interleukin 6 in colon extracts and
serum as well as interferon gamma by splenic and lamina propria
CD4+ T cells. VIP reduced disease severity when given after disease
onset and dramatically reduced disease recurrence given a second
dose of TNBS. Conclusions: Our data suggest that VIP has
beneficial prophylactic and therapeutic effects in TNBS-induced
colitis and is a promising candidate to test for potential benefits
in CD. ![]()
Emergence of perianal fistulizing disease in the SAMP1/YitFc
mouse, a spontaneous model of chronic ileitis
J. Rivera-Nieves, G. Bamias, A. Vidrich, M. Marini, T. T. Pizarro,
M. J. McDuffie, C. A. Moskaluk, S. M. Cohn, F. Cominelli
Background & Aims: SAMP1/Yit mice spontaneously develop
chronic terminal ileitis, reminiscent of the human disease described
by Crohn et al. in 1932. Several new phenotypic features have
appeared in our colony after more than 20 generations of brother-sister
mating. In this report, we describe the distinguishing features
of the SAMP1/YitFc substrain at the University of Virginia, compared
with the Japanese SAMP1/Yit parental strain. Methods: A
colony of SAMP1/Yit mice was established at the University of
Virginia in 1996, from 2 breeding pairs obtained from Japan. A
systematic characterization of their phenotypic and immunologic
characteristics was performed at 4, 10, 40, and more than 60 weeks
of age. Results: The following differences were observed:
(1) SAMP1/YitFc mice displayed established ileitis as early as
10 weeks of age, (2) the incidence of skin lesions inversely correlated
with the occurrence of intestinal inflammation, (3) mice develop
chronic ileitis with prominent muscular hypertrophy and focal
collagen deposition in inflamed segments, (4) mesenteric lymph
node lymphocytes acquired an activated phenotype coincident with
disease progression, (5) high interferon- production was detected
by 4 weeks of age and preceded the onset of ileitis, and (6) a
subgroup of mice (~5%) developed perianal disease with ulceration
and fistulae. Conclusions: The SAMP1/YitFc substrain exhibits
unique characteristics when compared with the original Japanese
strain. Of particular interest is the emergence of perianal fistulizing
disease, to our knowledge the first report of such occurrence
in an animal model of inflammatory bowel disease. ![]()
Helicobacter pylori induces matrix metalloproteinase-9 through
activation of nuclear factor B
N. Mori, H. Sato, T. Hayashibara, M. Senba, R. Geleziunas, A.
Wada, T. Hirayama, N. Yamamoto
Background & Aims: Matrix metalloproteinases (MMPs),
enzymes capable of degrading extracellular matrix components,
are believed to be active in connective tissue remodeling associated
with various physiologic processes and in pathologic conditions.
The aim of this study was to analyze the molecular mechanism responsible
for Helicobacter pylori-mediated MMP expression. Methods:
Expression of MMP messenger RNA and MMP activity were assessed
by reverse-transcription polymerase chain reaction and zymography,
respectively. Chloramphenicol acetyltransferase assay was used
to monitor activation of the MMP-9 gene promoter, and electrophoretic
mobility shift assay was used to explore the binding of transcription
factors to this promoter. Gastric tissue samples were immunohistochemically
stained for MMP-9. Results: H. pylori induced MMP-9
expression in 2 gastric epithelial cell lines but had no effect
on MMP-2. Induction of MMP-9 was dependent on an intact cag
pathogenicity island. Activation of the MMP-9 promoter by H.
pylori occurred through the action of nuclear factor B. Transfection
of kinase-deficient mutants of IB kinase and nuclear factor B-inducing
kinase inhibited H. pylori-mediated activation of MMP-9.
MMP-9 expression was higher in epithelial cells of H. pylori-positive
tissue compared with those of H. pylori-negative tissue.
Conclusions: H. pylori induced activation of nuclear
factor B through an intracellular signaling pathway that involved
IB kinase and nuclear factor B-inducing kinase, leading to MMP-9
gene transcription. MMP-9 induction by H. pylori may play
an important role in gastric inflammation, ulcer formation, and
carcinogenesis. ![]()
CARD15/NOD2 functions as an antibacterial factor in human intestinal
epithelial cells
T. Hisamatsu, M. Suzuki, H.-C. Reinecker, W. J. Nadeau, B. A.
McCormick, D. K. Podolsky
Background & Aims: Mutations in the CARD15/NOD2 gene,
a putative intracellular pattern recognition receptor, have been
linked to the risk for Crohn's disease. Because intestinal epithelial
cells play a role as the barrier to luminal microorganisms, we
investigated the expression and function of CARD15/NOD2 in intestinal
epithelial cells. Methods: Expression of CARD15/NOD2 messenger
RNA (mRNA) in intestinal epithelial cell lines and primary intestinal
epithelial cells was assessed by reverse-transcription polymerase
chain reaction (RT-PCR). Regulation of expression of CARD15/NOD2
by cytokines was determined by Northern blot using the SW480 cell
line. Active CARD15/NOD2 protein in SW480 cells was assessed by
the combination of immunoprecipitation and immunoblotting using
anti-CARD15/NOD2 antisera. To identify the functional role of
CARD15/NOD2 in intestinal epithelial cells, gentamicin protection
assays of Salmonella typhimurium were performed using Caco2
cells stably transfected with either wild-type CARD15/NOD2 or
the 3020insC mutant associated with Crohn's disease. Results:
CARD15/NOD2 mRNA was expressed in both intestinal epithelial cell
lines and primary intestinal epithelial cells. CARD15/NOD2 mRNA
and protein were up-regulated by tumor necrosis factor (TNF) in
SW480 cells. The number of viable internalized S. typhimurium
in Caco2 cells stably transfected with CARD15/NOD2 expression
plasmid was lower than untransfected Caco2 cells or MOCK transfectant.
In contrast, expression of a variant associated with Crohn's disease
was unable to constrain bacterial survival. Conclusions:
CARD15/NOD2 is expressed in intestinal epithelial cells and may
serve as a key component of innate mucosal responses to luminal
bacteria as an antibacterial factor. Failure in this activity
may contribute to the development of Crohn's disease. ![]()
TNF- and IFN- regulate the expression of the NOD2 (CARD15)
gene in human intestinal epithelial cells
P. Rosenstiel, M. Fantini, K. Bräutigam, T. Kühbacher,
G. H. Waetzig, D. Seegert, S. Schreiber
Background & Aims: NOD2, a member of the NOD1/Apaf-1
family, was recently identified as the first susceptibility gene
for Crohn's disease. The aim of this report was to describe the
regulation and functional significance of NOD2 expression in intestinal
epithelial cells. Methods: Expression of NOD2 messenger
RNA was determined by reverse-transcription polymerase chain reaction
(RT-PCR); NOD2 protein was detected by Western blot. Promoter
activity was assessed by reporter gene assays and DNA-binding
of NF-B by electrophoretic mobility shift assays. IL-8 production
was investigated by RT-PCR and enzyme-linked immunosorbent assay.
Results: TNF- induced an up-regulation of NOD2 in epithelial
cell lines (HT-29, SW620, SW948, HeLa S3) and in primary colonic
epithelial cells. A synergism was seen by cotreatment with IFN-.
Two NF-B binding sites were identified in the promoter. Deletion
of either site or overexpression of dominant negative IB led to
reduced levels of TNF-/IFN--stimulated reporter gene activity.
The identified B3 site was bound by NF-B as determined by gelshift
assays. Elevated amounts of NOD2 protein were also found in colonic
epithelial cells from patients with IBD. LPS induced high levels
of IL-8 production in SW620 cells overexpressing NOD2. Conclusions:
TNF-(/IFN-) treatment up-regulates the expression of the NOD2
gene in intestinal epithelial cells and subsequently increases
their LPS susceptibility. Together with the mutation-derived truncation
and functional change of the NOD2 protein, this could be part
of the complex pathophysiology of barrier disruption as it is
observed in inflammatory bowel diseases. ![]()
Basic-Liver, Pancreas, and Biliary Tract
Angiotensin-converting enzyme inhibitor attenuates pancreatic
inflammation and fibrosis in male Wistar Bonn/Kobori rats
A. Kuno, T. Yamada, K. Masuda, K. Ogawa, M. Sogawa, S. Nakamura,
T. Nakazawa, H. Ohara, T. Nomura, T. Joh, T. Shirai, M. Itoh
Background & Aims: Pancreatic stellate cells have some
similarities to hepatic stellate cells and an intrinsic renin-angiotensin
system is present in the pancreas and is enhanced in acute pancreatitis
and chronic pancreatic hypoxia. We assessed the effects of lisinopril,
an angiotensin-converting enzyme (ACE) inhibitor, on spontaneously
occurring chronic pancreatitis. Methods: Lisinopril in
drinking water (20, 50, or 200 mg/L) was administered to 10-week-old
male Wistar Bonn/Kobori (WBN/Kob) rats for 10 weeks and then the
inflammatory parameters, fibrosis, serum and pancreatic ACE activity,
and expression of transforming growth factor-1 (TGF-1) messenger
RNA (mRNA) as well as positive immunostaining for -smooth muscle
actin (-SMA) were assessed. Results: Lisinopril attenuated
gross alterations in the pancreas. This protective effect was
confirmed quantitatively by significant increases in pancreatic
weights and decreases in pancreatic myeloperoxidase (MPO) activity
(an index of granulocyte infiltration), pancreatic hydroxyproline
content (an index of collagen deposition), ratio of fibrous tissue,
and histologic scores. Lisinopril significantly reduced serum
ACE activity but it did not affect pancreatic activity. High doses
of lisinopril suppressed the overexpression of TGF-1 mRNA measured
by reverse-transcription polymerase chain reaction (RT-PCR) and
decreased the number of -SMA-positive cells (activated pancreatic
stellate cells) in the pancreas. Conclusions: Lisinopril
alleviated chronic pancreatitis and fibrosis in male WBN/Kob rats.
It suppressed the expression of TGF-1 mRNA, resulting in the prevention
of pancreatic stellate cell activation, which may be involved
in the observed protection. We propose that an ACE inhibitor may
be useful for treating chronic pancreatitis. ![]()
Overexpression of heparin-binding EGF-like growth factor in
mouse pancreas results in fibrosis and epithelial metaplasia
A. L. Means, K. C. Ray, A. B. Singh, M. K. Washington, R. H. Whitehead,
R. C. Harris, Jr., C. V. E. Wright, R. J. Coffey, Jr., S. D. Leach
Background & Aims: Heparin-binding epidermal growth
factor-like growth factor (HB-EGF) is expressed in both normal
pancreatic islets and in pancreatic cancers, but its role in pancreatic
physiology and disease is not known. This report examines the
effects of HB-EGF overexpression in mouse pancreas. Methods:
Transgenic mice were established using a tissue-specific promoter
to express an HB-EGF complementary DNA in pancreatic cells, effectively
elevating HB-EGF protein 3-fold over endogenous levels. Results:
Mice overexpressing HB-EGF in pancreatic islets showed both endocrine
and exocrine pancreatic defects. Initially, islets from transgenic
mice failed to segregate , , , and PP cells appropriately within
islets, and had impaired separation from ducts and acini. Increased
stroma was detected within transgenic islets, expanding with age
to cause fibrosis of both endocrine and exocrine compartments.
In addition to these structural abnormalities, subsets of transgenic
mice developed profound hyperglycemia and/or proliferation of
metaplastic ductal epithelium. Both conditions were associated
with severe stromal expansion, suggesting a role for islet/stromal
interaction in the onset of the pancreatic disease initiated by
HB-EGF. Supporting this conclusion, primary mouse fibroblasts
adhered to transgenic islets when the 2 tissues were cocultured
in vitro, but did not interact with nontransgenic islets. Conclusions:
An elevation in HB-EGF protein in pancreatic islets led to altered
interactions among islet cells and among islets, stromal tissues,
and ductal epithelium. Many of the observed phenotypes appeared
to involve altered cell adhesion. These data support a role for
islet factors in the development of both endocrine and exocrine
disease. ![]()
Case Reports
A multidrug resistance 3 gene mutation causing cholelithiasis,
cholestasis of pregnancy, and adulthood biliary cirrhosis
J.-F. Lucena, J. I. Herrero, J. Quiroga, B. Sangro, J. Garcia-Foncillas,
N. Zabalegui, J. Sola, M. Herraiz, J. F. Medina, J. Prieto
We describe a 47-year-old patient who developed cholelithiasis
in adolescence, followed by recurrent intrahepatic cholestasis
of pregnancy, and finally biliary cirrhosis in adulthood. In our
patient, the consecutive presentation of the 3 mentioned disorders
raised the suspicion of a defect of MDR3, the canalicular protein
involved in the transport of phospatidylcholine to bile. Mutational
analysis in our patient showed a heterozygous missense mutation
of the MDR3 gene that has not been described previously, which
occurs in exon 14 at codon 535, and results in the substitution
of glycine for aspartic acid. Further analysis of 7 members of
the family showed the same mutation in her daughter who, on follow-up,
developed cholestasis of pregnancy and persisting high serum levels
of -glutamyl transpeptidase and alkaline phosphatase after delivery.
Although biliary cirrhosis associated with MDR3 deficiency typically
appears before the age of 25 years, in our case, the relatively
mild MDR3 dysfunction allowed for a slower progression of the
disease with established, well-advanced cirrhosis in the fifth
decade of life. The present case, which accumulates the 3 clinical
disorders assocaited with MDR3 deficiency, shows that this condition
should be suspected not only in children or young people with
high -glutamyl transpeptidase cholestasis but also in middle-aged
or older patients with chronic idiopathic cholestasis, especially
when there is a previous history of cholestasis of pregnancy or
juvenile cholelithiasis. ![]()
Special Reports and Reviews
Lipoxins: Pro-resolution lipid mediators in intestinal inflammation
J. Goh, C. Godson, H. R. Brady, P. MacMathuna
Many inflammatory processes are self-limiting, suggesting the
existence of endogenous anti-inflammatory mechanisms. Among the
lipid mediators generated during cell-cell interactions are the
lipoxins (LX, including LXA4 and B4), a distinct class of lipoxygenase-derived
eicosanoids. Aspirin acetylation of cyclooxygenase 2 also promotes
the generation of a series of 15-epimers of LXA4, known as aspirin-triggered
lipoxins (ATL), that may account for some of the bioactivity profile
of aspirin and possibly of nonsteroidal anti-inflammatory drugs.
Native LX are rapidly inactivated in vivo, and stable analogs
of LXA4, LXB4, and ATL have been synthesized that possess enhanced
bioavailability and potency as anti-inflammatory eicosanoids.
Here, we review current in vitro, ex vivo, and in vivo evidence
supporting cytoprotective and proresolution roles for LX in intestinal
inflammation. LXA4, LXA4 analogs, and ATL analogs inhibit neutrophil
chemotaxis, adhesion to epithelium, and epithelial cell chemokine
release. In addition, LX blunt TNF--stimulated inflammatory responses,
cyclooxygenase product generation, and epithelial cell apoptosis
and are cytoprotective for cytokine-activated colonic mucosa ex
vivo. LX, ATL, and synthetic LX analogs have already been demonstrated
to possess impressive antiinflammatory and proresolution efficacy
in a range of experimental models of inflammation in vivo. Further
elucidation of the role of LX in intestinal epithelial cell biology
and immune function may yield novel therapeutic approaches in
inflammatory bowel disease and possibly gastrointestinal cancer.![]()
Copyright 2003 Elsevier Science (USA). All rights reserved.
Table of Contents for Journal of Hepatology Volume 38, Issue 4, April 2003
Biliary Tract and Cholestasis
Peter Fickert et al.
Mallory body formation in primary biliary cirrhosis is associated
with increased amounts and abnormal phosphorylation and ubiquitination
of cytokeratins
Background/Aims: Animal studies revealed a key role of toxic
bile acids in the regulation of hepatocytic cytokeratin (CK) expression
and Mallory body (MB) formation. In this study, we compared CK
expression, phosphorylation, and ubiquitination in primary biliary
cirrhosis (PBC), chronic hepatitis C (CHC) and control livers
to determine whether bile acid-induced CK alterations are associated
with cytoskeletal alterations and MB formation in a prototypic
chronic cholestatic liver disease. Methods: CK 8 and CK
18 mRNA and protein levels were investigated by reverse transcriptase-polymerase
chain reaction and Western blotting. Intermediate filament (IF)
cytoskeletal alterations were assessed by immunofluorescence microscopy
using antibodies against CKs, CK phosphoepitopes, MBs, and ubiquitin.
Results: Despite unchanged mRNA levels, CK 8 and CK 18
protein levels were significantly elevated in PBC suggesting stabilization
of CKs, possibly due to decreased degradation. CK-IF alterations
in PBC comprised increased density with abnormal phosphorylation
of the IF network of hepatocytes in acinar zone 1 and in the periphery
of cirrhotic nodules. In addition, in these areas hepatocytes
with diminished IF network containing MBs consisting of abnormally
phosphorylated and ubiquitinated CK were observed. Conclusions:
These findings support our concept that IF cytoskeletal alterations
and MB formation in cholestatic liver diseases are related to
bile acid-induced cell stress.![]()
Ferenc Szalay et al.
High serum osteoprotegerin and low RANKL in primary biliary
cirrhosis
Background/Aims: Osteoprotegerin is decoy receptor for osteoclast
activating factor, RANKL, and impairs osteoclast funtion. Since
osteoporosis is common in primary biliary cirrhosis (PBC), we
investigated osteoprotegerin, RANKL and markers of bone turnover
in PBC. Methods: Serum osteoprotegerin, RANKL, osteocalcin
(OC) and C-terminal cross-linking telopeptide of type I collagen
(CTX-I) were measured by ELISA in 41 patients with PBC, 16 women
with chronic hepatitis C (CHC), and as controls in 44 age-matched
healthy and 74 post-menopausal osteopenic otherwise healthy women.
Results: Serum osteoprotegerin levels were higher in PBC
patients (7.8±3.0pmol/l) than in healthy controls (4.4±2.3pmol/l)
and osteopenic women (4.0±1.0pmol/l, P<0.0001
for both). RANKL levels were lower in PBC (0.9±1.8pmol/l,
P<0.0001) than in healthy controls (1.3±0.5pmol/l).
In CHC both osteoprotegerin (9.7±4.2pmol/l) and RANKL (3.2±4.7pmol/l)
were elevated compared to the control groups (P<0.0001,
for both). There was a positive correlation between serum osteoprotegerin
and OC, CTX-I and AST but not with bone mineral density in PBC.
Conclusions: The mechanisms and role of elevated osteoprotegerin
and low RANKL in PBC are unclear, but it might partly represent
a compensatory mechanism to negative balance of bone remodeling.
High OPG and RANKL levels found in CHC might suggest that inflammatory
process in the liver could also contribute to the elevation of
osteoprotegerin.![]()
Pietro Invernizzi et al.
Peculiar HLA polymorphisms in Italian patients with primary
biliary cirrhosis
Background/Aims: Primary biliary cirrhosis (PBC) is an autoimmune
cholestatic liver disease of unknown etiology with a highly variable
progression rate and prevalence among different geographical areas.
Data concerning human leukocyte antigen (HLA) polymorphisms in
PBC come from a limited number of geographical areas, from which
the association with the HLA-DRB1*08 allele has been consistently
reported. Methods: To investigate whether HLA polymorphisms
contribute toward disease susceptibility, we compared 186 well-defined
Italian PBC patients with 558 healthy subjects matched by age,
gender and geographical area (Northern, Central and Southern Italy).
Patients and controls were HLA typed at low resolution by PCR-sequence
specific oligonucleotides for the loci A and B; HLA-DRB1 alleles
were typed by reverse line blot assay of PCR-amplified DNA. Results:
HLA-DRB1*11 was associated with a markedly reduced risk of developing
PBC (OR: 0.3; 95% CI: 0.2-0.5). No association was found with
HLA-DRB1*08. The B*15 (2.5; 1.3-4.6), B*41 (12.0; 2.7-72.1), B*55
(2.9; 1.1-7.5) and B*58 alleles (6.8; 1.1-46.3) were more frequent
in PBC. The frequency of HLA polymorphisms was similar in PBC
patients with progressive or non-progressive disease, and in those
with or without anti-mitochondrial antibodies. Conclusions:
Our data on a large series of Italian patients suggest that PBC
may have a peculiar genetic background in the Mediterranean area.![]()
Cell Biology, Metabolism and Transport
Masaki Kaibori et al.
Hepatocyte growth factor inhibits insulin-stimulated glycogen
synthesis in primary cultured hepatocytes
Background/Aims: Hepatocyte growth factor (HGF) plays an important
role as a mitogen in liver regeneration. However, little is known
about the metabolic effects of HGF in the liver. Studies were
performed to examine whether HGF influences carbohydrate metabolism,
which is drastically changed in the early course of the regeneration.
Methods: Primary cultured rat hepatocytes were treated
with glucoregulatory hormones such as insulin, glucagon and adrenaline
in the presence or absence of HGF. Cellular glycogen deposition
and activities of its metabolic enzymes were compared. Results:
HGF inhibited insulin-stimulated glycogen deposition, but had
no effect on glycogen degradation stimulated by glucagon and adrenaline.
HGF decreased glycogen synthase activity and increased glycogen
phosphorylase activity in insulin-stimulated hepatocytes, resulting
in the inhibition of glycogen synthesis. Experiments with immunoprecipitation
revealed that HGF had no effect on the upstream of insulin signaling
including an activation of its receptor and association of insulin
receptor substrate with phosphatidylinositol 3-kinase, indicating
that HGF presumably affects further downstream of these events.
Conclusions: These results demonstrate that HGF interacts
with insulin on glucose metabolism in hepatocytes. HGF may be
involved in glucose regulation, and contribute to cell growth
and maturation in addition to its mitogenic action during liver
regeneration.![]()
Chronic Liver Diseases
Shahin Merat et al.
Probucol in the treatment of non-alcoholic steatohepatitis:
a double-blind randomized controlled study
Background/Aims: A final step in the pathology of non-alcoholic
steatohepatitis (NASH) is oxidative damage to hepatocytes. Probucol
is a lipid-lowering agent with strong antioxidant properties.
We designed a double-blind randomized controlled study to evaluate
the effects of probucol in NASH. Methods: Thirty cases
of biopsy-proven NASH were included. Subjects were randomly allocated
to either the treatment group or to the control group by a 2:1
ratio. The treatment group was given 500mg of probucol daily for
6 months, and the control group, an identically appearing placebo.
Results: Twenty-seven cases completed the study. The mean
aspartate transaminase (AST) and alanine transaminase (ALT) levels
changed from 81.9 to 36.2 and 102.2 to 44.7 in the treatment group
and from 57.6 to 49.6 and 96.8 to 96.2 in the control group, respectively.
The decrease in ALT level in the treatment group as compared to
the control group was significant at the P<0.005 level
(95% confidence interval: 20.2-93.7IU). Both AST and ALT levels
dropped to normal in nine cases of the treatment group (50%) but
none of the control group (P=0.01). Conclusions:
Probucol appears to be significantly effective in decreasing the
ALT levels in patients with NASH.![]()
Herbert Tilg et al.
Anti-tumor necrosis factor-alpha monoclonal antibody therapy
in severe alcoholic hepatitis
Background/Aims: Severe alcoholic hepatitis (AH) is associated
with high mortality. Tumor necrosis factor-alpha (TNF) has been
demonstrated to play an important role in its pathophysiology.
Methods: Twelve patients with biopsy-confirmed AH and a
Maddrey discriminant factor >32 were treated with a single
infusion of the anti-TNF monoclonal antibody Infliximab at a dose
of 5mg/kg body weight. Serial measurements were made for various
cytokines using specific enzyme-linked immunoassays (ELISA). In
four patients, liver biopsy samples were available pretreatment
and on day+28 of therapy. Results: Ten of the 12 patients
are alive at a median of 15 (12-20) months. Two patients died
within 30 days from septicemia. Serum bilirubin levels, Maddrey
score, neutrophil count and C-reactive protein fell significantly
within the first month. There was an early, though not significant,
decrease in plasma levels of proinflammatory cytokines (interleukins
(IL)-1, IL-6, IL-8, interferon-gamma), whereas plasma levels of
TNF remained near the sensitivity limit of the assay throughout
the treatment course. While TNF mRNA expression in the liver did
not change, expression of IL-8, a cytokine regulated mainly by
TNF, was almost absent on day+28. Conclusions: Our data
suggest that randomized controlled trials of anti-TNF antibody
in severe AH are warranted.![]()
Kim R. Bridle et al.
Evidence for a sub-morphological inflammatory process in the
liver in haemochromatosis
Background/Aims: The role of cytokines in hepatic injury has
been examined for many liver diseases however little is known
of the cytokine involvement in haemochromatosis. The aim of the
current study was to examine the hepatic gene expression of potential
proinflammatory and profibrogenic cytokines in haemochromatosis.
Methods: Interferon-, interleukin-10, transforming growth
factor-1 and tumor necrosis factor- mRNA expression was assessed
in liver tissue from 20 haemochromatosis patients, eight controls
and eight chronic hepatitis C patients. To assess the immunophenotype
of the inflammatory infiltrate in haemochromatosis, liver sections
were subjected to immunohistochemistry using markers for macrophages
(CD68, HAM56, MAC387) or T cells (CD3 and CD45RO). Results:
Interferon- mRNA was increased in both haemochromatosis (0.29±0.08%,
P=0.01) and hepatitis C patients (1.02±0.32%, P=0.03)
compared to controls (0.04±0.01%). Interleukin-10 mRNA
was significantly decreased in both haemochromatosis and hepatitis
C patients (0.01±0.003%, P=0.008 and 0.03±0.015%,
P=0.02, respectively) compared to controls (0.12±0.01%).
CD3 positive T-cell number was significantly correlated with increasing
hepatic iron concentration (r=0.56, P=0.03). Conclusions:
This study has demonstrated a distinct pattern of cytokine gene
expression in haemochromatosis, which resembles that of inflammatory
conditions such as chronic hepatitis C. These factors may play
a role in the development of iron-induced hepatic fibrosis in
haemochromatosis.![]()
Brent A. Neuschwander-Tetri et al.
Interim results of a pilot study demonstrating the early effects
of the PPAR- ligand rosiglitazone on insulin sensitivity, aminotransferases,
hepatic steatosis and body weight in patients with non-alcoholic
steatohepatitis
Background/Aims: Hyperinsulinemia may cause hepatic steatosis
and non-alcoholic steatohepatitis (NASH). The aims of this pilot
study were to examine the safety of using the insulin-sensitizing
peroxisomal proliferator activated receptor (PPAR) ligand rosiglitazone
in patients with NASH and determine whether improved insulin sensitivity
correlates with improved fatty liver. Methods: Thirty subjects
with NASH and elevated alanine aminotransferase (ALT) levels received
rosiglitazone, 4mg twice daily for 48 weeks; the preliminary results
presented here were obtained at 24 weeks. Insulin sensitivity
was measured using fasting insulin and glucose levels and liver
fat content was estimated by CT imaging. Results: By 24
weeks, rosiglitazone improved insulin sensitivity and reduced
liver fat content. The mean ALT decreased from 86 to 37U/l (P<0.01).
Four subjects (13%) withdrew, one because of a rise in ALT from
59 to 277U/l that coincided with concomitant prednisone use. Subjects
experienced a mean weight gain of 3.5% and hemoglobin drop of
1.1g/dl. Conclusions: Treatment of NASH with rosiglitazone
for 24 weeks improved insulin sensitivity, reduced liver fat content
and improved biochemical evidence of hepatocellular injury. These
preliminary data provide evidence that hyperinsulinemia may be
a cause of NASH. Strategies to improve insulin sensitivity as
a treatment of NASH deserve further investigation.![]()
Cirrhosis and its Complications
Francesca Nicolao et al.
Role of determination of partial pressure of ammonia in cirrhotic
patients with and without hepatic encephalopathy
Background/Aims: To compare venous, arterial and partial pressure
of ammonia (pNH3) in 27 consecutive cirrhotics with hepatic encephalopathy,
15 cirrhotics without hepatic encephalopathy and nine controls;
to reevaluate all parameters after the improvement of encephalopathy.
Methods: Patients were studied by clinical examination
and psychometric testing. pNH3 was calculated from arterial ammonia
and pH. Results: In patients with encephalopathy, each
form of ammonia was higher than in both controls and patients
without encephalopathy. The correlation with the severity of hepatic
encephalopathy was similar for venous (r=0.72), arterial
ammonia (r=0.76) and pNH3 (r=0.75). The sensitivity
and specificity of each variable in correctly classifying the
patients as having or not having hepatic encephalopathy was also
similar. Each form of ammonia decreased after the resolution or
amelioration of symptoms. However, even in the 17 patients with
complete resolution of hepatic encephalopathy, all three ammonia
determinations resulted unchanged or increased in some patients.
Conclusions: Despite the significant correlation between
pNH3 and hepatic encephalopathy, our study suggests that neither
pNH3 nor arterial ammonia are, from a clinical point of view,
more useful than venous ammonia: all three determinations being
limited both for the diagnosis of hepatic encephalopathy and for
the clinical management of the patients.![]()
Frank Tacke et al.
Ghrelin in chronic liver disease
Background/Aims: Ghrelin is a novel endogenous ligand for
the growth hormone (GH) secretagogue receptor involved in energy
metabolism, glucose homeostasis and food intake. We investigated
the role of ghrelin and insulin-like growth factor-1 (IGF-1),
the mediator of the GH axis, in patients with chronic liver diseases
(CLD). Methods: Ghrelin and IGF-1 serum levels were determined
in 105 CLD patients and 97 healthy controls and correlated with
clinical and biochemical parameters. Results: Ghrelin was
significantly elevated and IGF-1 reduced in CLD patients compared
with healthy controls. IGF-1 serum levels inversely correlated
with Child's classification. Ghrelin levels were significantly
elevated in Child C cirrhosis patients independent of the aetiology
of liver disease. Ghrelin levels did not correlate with liver
function. In contrast, there was a correlation of ghrelin with
clinical (gastrointestinal bleeding, ascites, encephalopathy)
and biochemical (anaemia, inflammatory markers, hypoglycaemia,
renal dysfunction) parameters. In a subgroup of patients with
CLD and hepatocellular carcinoma (HCC), we observed a strong inverse
correlation between alpha-fetoprotein (AFP) and ghrelin levels.
Conclusions: Unlike IGF-1, ghrelin is not correlated with
liver function, but increases in Child C cirrhosis and with complications
of CLD. The inverse correlation with AFP in HCC patients requires
further studies on the potential impact of ghrelin on the pathogenesis
of anorexia-cachexia syndrome.![]()
Wilma Debernardi Venon et al.
Effects of long-term Irbesartan in reducing portal pressure
in cirrhotic patients: comparison with propranolol in a randomised
controlled study
Background/Aims: The role of angiotensin II (AT-II) type I
receptor antagonists in the treatment of portal hypertension remains
controversial. We tested the efficacy of Irbesartan (Irb) vs.
Propranolol (Pro) in reducing portal pressure and evaluated its
systemic haemodynamic effects. Methods: Thirty-four patients
were randomly assigned to receive either Irb 300mg/day (19 patients)
or Pro 40-120mg/day (15 patients) for 2 months. Results:
Irb was discontinued in five patients (26%). No major side effect
occurred in the Pro group. On an average, the portal pressure
gradient decreased significantly more in the Pro than in the Irb
group (median 19.5%, range 11/31% vs. 4.8%, +2.5/10%, P<0.001).
A clinically significant decrease was seen in one (7%) of the
patients given Irb vs. five (33%) given Pro (P<0.02).
The fall in mean arterial pressure was significantly higher with
Irb than with Pro (median 29%, range 15/45% vs. 4.9%, +8/19%,
P<0.02). Irb significantly modified the blood creatinine
clearance (median 29ml/m, range +9/61ml/m, 30, 24/35% P<0.0001
vs. basal). Conclusions: Irb offers no advantage over Pro
in the control of portal hypertension. Moreover, its therapeutic
profile is limited by important side effects.![]()
Franco Trevisani et al.
QT interval in patients with non-cirrhotic portal hypertension
and in cirrhotic patients treated with transjugular intrahepatic
porto-systemic shunt
Background/Aims: A prolonged QT interval is frequent in chronic
liver disease and its aetiology remains unsettled. The study's
aim was to assess the role of portal hypertension in the pathogenesis
of QT prolongation. Methods: We measured the QT interval
in: (1) 10 patients with non-cirrhotic portal hypertension (NCPH)
and preserved liver function; (2) 19 cirrhotic patients before,
1-3 and 6-9 months after transjugular intrahepatic porto-systemic
shunt (TIPS) insertion. Results: Baseline corrected maximum
QT interval (QTcmax) was prolonged (>440ms) in eight NCPH and
16 cirrhotic patients, and its value did not differ between the
two groups (453±8 vs. 465±6ms, P=NS). No
patients showed an abnormal baseline QT dispersion. In cirrhotic
individuals, QTcmax further increased 1-3 months after TIPS (P=0.042),
thereafter remaining steadily elevated. QT dispersion only increased
at the second post-TIPS determination (P=0.030). Such changes
occurred despite no deterioration of liver function, plasma electrolytes
and haemoglobin. Conclusions: QT interval is frequently
prolonged in patient with both non-cirrhotic and cirrhotic portal
hypertension and portal decompression by TIPS worsens this abnormality.
These results suggest that the porto-systemic shunting is responsible
for the altered ventricular repolarisation possibly through a
dumping into the systemic circulation of splanchnic-derived cardioactive
substances.![]()
Inflammation and Fibrosis
Toshihiro Nishio et al.
Increased expression of collagenase in the liver induces hepatocyte
proliferation with cytoplasmic accumulation of -catenin in the
rat
Background/Aims: Since the hepatic extracellular matrix is
remodeled in liver regeneration, we investigated whether increased
collagenase activity in the liver can induce hepatocyte proliferation
in vivo. Methods: To increase hepatic collagenase activity,
human matrix metalloproteinase-1 was delivered to the rat liver
by the recombinant adenoviral vector Ad5MMP-1. Results:
Hepatic delivery of Ad5MMP-1 increased the 5-bromo-2-deoxyuridine
labeling index and mitotic index in hepatocytes, causing an increase
in the dry liver weight; control adenovirus, Ad5LacZ, had minimal
effect. Hepatocyte proliferation started approximately 48 h after
infection with Ad5MMP-1 and ended after about 2 weeks. The increase
in the dry liver weight also returned to baseline after 2 weeks.
Transient liver injury by Ad5MMP-1, reflected by increased aspartate
and alanine aminotransferase levels, peaked around 1 week, and
was associated with hepatocyte apoptosis. Collagenase-induced
hepatocyte proliferation was accompanied by cytoplasmic accumulation
of -catenin and a transient decrease in E-cadherin expression.
Conclusions: Modification of the hepatic extracellular
matrix by collagenase induces transient hepatocyte proliferation
in vivo, suggesting that the condition of the hepatic extracellular
matrix per se plays a pivotal role in regulating hepatocyte proliferation.![]()
Liver Cell Injury and Liver Failure
Thomas S. Weiss, Sascha Pahernik, Irmgard Scheruebl, Karl-Walter
Jauch and Wolfgang E. Thasler
Cellular damage to human hepatocytes through repeated application
of 5-aminolevulinic acid
Background/Aims: 5-Aminolevulinic acid (ALA), a precursor
of porphyrins is used for photodynamic diagnosis and therapy within
topical or systemic applications. A potential toxic effect on
the human liver is of major interest and therefore we investigated
the impact of a repeated application of ALA without illumination
on cultures of human hepatocytes. Methods: After ALA treatment
of hepatocytes in vitro the porphyrin synthesis, albumin secretion,
liver-specific enzyme release, and malondialdehyde levels were
determined. In order to reduce levels of reactive oxygen substances,
mannitol and the antioxidant enzymes superoxide dismutase and
catalase were supplemented. Results: Porphyrin biosynthesis
by human hepatocytes in vitro was repeatedly stimulated by ALA
(0.001-1.0 mM), which was indicated by an accumulation of protoporphyrin
IX. A repetitive treatment (up to four times) of hepatocytes with
ALA resulted in an impairment of the hepatic function and viability,
depending on the ALA concentration (0.1-1.0 mM) and frequency
of application (2-3 times). This was also accompanied by increased
malondialdehyde levels indicating enhanced lipid peroxidation.
Only superoxide dismutase was able to reduce cellular damage and
prevent specific function. Conclusions: Repeated, not single,
ALA treatment without illumination may cause deleterious effects
to the liver, which are mediated by oxygen radicals and inhibited
by an antioxidant.![]()
Fuminori Hirano, Keiji Komura, Etsushi Fukawa and Isao Makino
Tumor necrosis factor (TNF-)-induced RANTES chemokine expression
via activation of NF-B and p38 MAP kinase: roles of TNF- in alcoholic
liver diseases
Background/Aims: Increased concentration of plasma tumor necrosis
factor (TNF-) correlates with the clinical course of alcoholic
liver diseases. In addition, hepatic RANTES which migrates CD4
T lymphocytes to liver is increased in patients with alcoholic
hepatitis. We investigated that roles of TNF- on RANTES expression
in hepatocytes. Methods: HLE cells were treated with TNF-
in the presence, or absence of several inhibitors. Enzyme-linked
immunoassay and reverse transcriptase-polymerase chain reaction
were performed for the measurement of protein production and mRNA
of RANTES, respectively. Moreover, DNA-binding activity of NF-B
was investigated using electrophoretic mobility shift assay. To
examine effects of TNF- on RANTES gene expression, luciferase
assay was performed. Results: TNF- clearly up-regulated
RANTES expression in a time-dependent fashion and induced DNA-binding
activity of NF-B. Moreover, TNF--induced RANTES expression was
completely inhibited by SB203580, but not calphostin C and wortmannin.
Luciferase assay showed that TNF- increased RANTES gene expression
and mutation of NF-B binding sites in the RANTES promoter ablated
TNF- inducibility. Conclusions: We showed that RANTES was
transcriptionally induced in human hepatoma cells by treatment
with TNF- via activation of NF-B and p38 MAP kinase, presumably
suggesting that TNF--induced expression of RANTES plays important
roles in cell-mediated liver injury in alcoholic liver diseases.![]()
Cell Injury and Liver Failure
Alexandra K. Kiemer et al.
Kupffer-cell specific induction of heme oxygenase 1 (hsp32)
by the atrial natriuretic peptide role of cGMP
Background/Aims: Pretreatment with atrial natriuretic peptide
(ANP) attenuates ischemia-reperfusion injury of livers via cGMP.
Heme oxygenase-1 (HO-1) is known as a protective mediator in ischemia-reperfusion
injury. The aim of this study was to investigate whether ANP affects
the expression of HO-1. Methods: Rat livers were perfused
with KH-buffer with/without ANP or 8-Br-cGMP, kept in UW solution
(4,°C, 24 h), and reperfused. HO-1 mRNA and protein was determined
by Northern and Western blot, in situ hybridization, and immunohistochemistry
in livers or isolated liver cells. Results: ANP significantly
elevated HO-1 mRNA expression at the end of the preconditioning
period and was without effects at the end of ischemia and during
reperfusion. 8-Br-cGMP did not affect HO-1 mRNA expression. In
situ hybridization as well as immunohistological double-staining
revealed that Kupffer cells but not hepatocytes showed HO-1 mRNA
and protein expression. Hepatocytes revealed no changes in HO-1
protein whereas Kupffer cells showed a marked increase in HO-1
protein after ANP treatment. Inhibition of HO-1 did not abrogate
hepatoprotection conveyed by ANP. Conclusion: Our data
show the potency of ANP to specifically induce HO-1 in Kupffer
cells independently of cGMP. This increased expression of HO-1
is not involved in hepatoprotection conferred by ANP being in
line with the knowledge that ANP mediates hepatoprotection via
cGMP.![]()
Viral Hepatitis
Silvia Fargion et al.
Sustained response to combination therapy in patients with
chronic hepatitis C who failed to respond to interferon
Background/Aims: The best treatment for chronic hepatitis
C patients who do not respond to interferon is still unknown.
Reported rates of response to treatment vary as the result of
heterogeneous definitions of non-responders and small study size.
Methods: One hundred nineteen hepatitis C virus (HCV) RNA-positive
non-responders to high-dose interferon monotherapy received alpha-interferon,
5 MU tiw plus oral ribavirin, 1000-1200 mg/day for 48 weeks (Group
A, n=74) or alpha-interferon, 5 MU daily for 4 weeks, followed
by 5 MU tiw plus oral ribavirin, 1000-1200 mg/day for 44 weeks
(Group B, n=45) according to the Institution where they
were followed. Persistently normal alanine aminotransferase and
negative HCV RNA up to 72 weeks from treatment onset defined a
sustained response. Results: Eighteen patients discontinued
treatment (13 developed anemia, two mucositis, one granulocytopenia;
two were dropouts), none for serious adverse events. There were
24 (20%) sustained responders, with similar final response rates
in Groups A and B. Sustained response was more frequent in patients
aged 40 years (36% vs. 13%; P=0.006) and in those with
non-1 genotype (44% vs. 14%; P=0.002). Among genotype 1
patients, the younger ones showed higher response rates (32% vs.
7%; P=0.005). Compared with patients harboring non-1 genotypes,
the odds ratio of being a non-responder was 1.68 (confidence interval
(CI): 0.53-5.37; P=0.381) in younger genotype 1 patients
and 9.53 (CI: 2.84-32; P<0.001) in older genotype 1
patients. Conclusions: Chronic hepatitis C patients who
are non-responders to interferon monotherapy and infected by non-1
genotypes should undergo re-treatment with combination therapy.
Treatment should be extended to younger genotype 1 patients who
are more susceptible to liver disease worsening because of longer
life expectancy and have a higher probability of being long lasting
responders than their older counterparts.![]()
Fatih Besisik et al.
Occult HBV infection and YMDD variants in hemodialysis patients
with chronic HCV infection
Background/Aims: End-stage renal disease patients on chronic
hemodialysis are at risk for both hepatitis B virus (HBV) and
hepatitis C virus (HCV) infection. Although the prevalence is
unknown in hemodialysis patients, occult HBV infection is frequent
in subjects with chronic HCV infection. We aimed to investigate
(1) the prevalence and clinical impact of occult HBV infection
in hemodialysis patients with chronic HCV infection, and (2) the
frequency of YMDD variants (tyrosine-methionine-aspartate-aspartate
amino acid motif of HBV polymerase) in this setting. Methods:
Thirty-three anti-HCV and HCV-RNA-positive, HBsAg-negative hemodialysis
patients (mean age 36.9±10.4 years, 22 male) were admitted
to this study. HBV-DNA (Innogenetics kit) and HCV-RNA (Cobas Amplicor
HCV kit) were investigated by polymerase chain reaction technique
(PCR). YMDD mutation was studied in all HBV-DNA-positive patients
by the BOOM method. Results: HBV-DNA was detected in 12
of 33 patients (36.4%) by PCR. Their mean age was 33.0±9.0
years. Age, dialysis period (years) and biochemical parameters
were not significantly different in patients with and without
occult HBV infection. YMDD variants were identified in six of
12 (50%) patients with occult HBV infection. Conclusions:
Occult HBV infection is frequent in hemodialysis patients with
chronic HCV infection. YMDD variants are common in this setting.![]()
Chee-Kin Hui, Tigist Belaye, Kevin Montegrande and Teresa Lyn
Wright
A comparison in the progression of liver fibrosis in chronic
hepatitis C between persistently normal and elevated transaminase
Background: Detectable serum hepatitis C virus (HCV) RNA in
HCV patients with persistently normal alanine transaminase (PNALT)
has been found to be associated with significant liver damage.
Aims: The primary outcome of this study was to compare
the histological progression of fibrosis in patients with PNALT
and elevated alanine transaminase (ALT). Methods: Forty
patients with PNALT (Group 1) and 41 patients with elevated ALT
(Group 2) were recruited into this study. Only patients with fibrosis
of F0 to F2 were recruited into this study. Results: The
median time to second liver biopsies was 6.3 (range 2.0-11.1)
years. Nine patients (22.5%) in Group 1 and 17 patients (41.5%)
from Group 2 had progression of fibrosis. There was a trend towards
a significantly higher cumulative probability of fibrosis progression
in Group 2 (P=0.06). In patients with an initial F0 to
F1 fibrosis, there was a significant difference in cumulative
probability of fibrosis progression between Groups 1 and 2 (22.6%
(7/31) vs. 43.3% (13/31), respectively, P=0.02). Conclusions:
Anti-HCV patients with PNALT with an initial fibrosis of F0 or
F1 were less likely to develop progression of fibrosis than those
with elevated ALT, although patients with PNALT may have histologically
and clinically progressive disease.![]()
Copyright © 2001-2003 European Association
for the Study of the Liver. All rights reserved.
5 April 2003 (Volume 326, Issue 7392)
Prevalence of Helicobacter pylori in patients
with gastro-oesophageal reflux disease: systematic review
Anan Raghunath, A Pali S Hungin, David Wooff, and Susan Childs
BMJ 2003; 326: 737. Prevalence of Helicobacter pylori
in patients with gastro-oesophageal reflux disease: systematic
review
Objectives: To ascertain the prevalence of Helicobacter
pylori in patients with gastro-oesophageal reflux disease
and its association with the disease.
Design: Systematic review of studies reporting the prevalence
of H pylori in patients with and without gastro-oesophageal
reflux disease.
Data sources: Four electronic databases, searched to November
2001, experts, pharmaceutical companies, and journals.
Main outcome measure: Odds ratio for prevalence of H
pylori in patients with gastro-oesophageal reflux disease.
Results: 20 studies were included. The pooled estimate
of the odds ratio for prevalence of H pylori was 0.60 (95%
confidence interval 0.47 to 0.78), indicating a lower prevalence
in patients with gastro-oesophageal reflux disease. Substantial
heterogeneity was observed between studies. Location seemed to
be an important factor, with a much lower prevalence of H pylori
in patients with gastro-oesophageal reflux disease in studies
from the Far East, despite a higher overall prevalence of infection
than western Europe and North America. Year of study was not a
source of heterogeneity.
Conclusion: The prevalence of H pylori infection
was significantly lower in patients with than without gastro-oesophageal
reflux, with geographical location being a strong contributor
to the heterogeneity between studies. Patients from the Far East
with reflux disease had a lower prevalence of H pylori
infection than patients from western Europe and North America,
despite a higher prevalence in the general population. ![]()
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