Biomedical subjects

Dominique Wendum

Publications and source records attributed to Dominique Wendum.

At least 19 recordsLinked to original sources

PubMed2006

Hepatocellular adenoma displaying a HNF1alpha inactivation in a patient with familial adenomatous polyposis coli.

Patients with familial adenomatous polyposis coli (FAP) may rarely develop hepatocellular adenoma. Here we report the case of a 37-year-old FAP woman presenting a hepatocellular adenoma after oestroprogestative oral contraception use. In this steatotic adenoma, we identified an inactivating biallelic mutation of HNF1alpha. In addition to the known germline APC mutation Q1062fs, we did not find an inactivation of the second APC allele nor an activation of the beta-catenin target genes GLUL and GPR49. Our findings contrast with two hepatocellular adenoma cases related to FAP, for which a biallelic inactivation of the APC gene was previously described. Altogether, these results suggest that benign hepatocellular carcinogenesis may be dependent on or independent of the Wnt/beta-catenin pathway in patients with FAP.

Adenomatous Polyposis Coli↗

PubMed2006

Liver adenomatosis: classification of MR imaging features and comparison with pathologic findings.

PURPOSE: To retrospectively compare the clinical manifestation and magnetic resonance (MR) imaging features of liver adenomatosis with pathologic findings. MATERIALS AND METHODS: This study had institutional review board approval, and informed consent was waived. Twenty patients were classified on the basis of pathologic findings into three groups: those with a steatotic, those with a peliotic, and those with a mixed (steatotic and peliotic) form of liver adenomatosis. MR images were reviewed in consensus by two abdominal radiologists, and findings were compared with the pathologic classification. Statistical evaluation was performed with the Student t test. RESULTS: All patients were women (mean age, 39 years +/- 10 [standard deviation]). Lesions of the steatotic form (n = 7) showed (a) a mean diameter of 6.3 cm +/- 1.7, (b) slightly hyperintense signal on T2-weighted images, (c) hyper- or isointense signal on T1-weighted images with a signal dropout with fat suppression sequences, and (d) moderate enhancement at the arterial phase with no delayed enhancement. Lesions of the peliotic form (n = 7) showed (a) a somewhat larger size (8.3 cm +/- 3.6), (b) markedly hyperintense signal on T2-weighted images, (c) iso- or hyperintensity on T1-weighted images with no signal dropout with fat suppression sequences, and (d) strong arterial enhancement and persistent enhancement at the portal and delayed phase. Lesions of the mixed form (n = 6) included a combination of imaging features of the steatotic and peliotic forms. Lesions, however, were significantly larger in the mixed form than in the steatotic form (10.3 cm +/- 4, P < .05). CONCLUSION: There are three patterns of MR imaging features of liver adenomatosis that are associated with three pathologic forms (steatotic, peliotic, and mixed).

Adenoma, Liver Cell↗

PubMed2006

Identification of a novel 974C-->G nonsense mutation of the MRP2/ABCC2 gene in a patient with Dubin-Johnson syndrome and analysis of the effects of rifampicin and ursodeoxycholic acid on serum bilirubin and bile acids.

Rifampicin (RIF) and ursodeoxycholic acid (UDCA) therapies have beneficial effects in chronic cholestatic diseases. These may result in part from the induction of multidrug-resistance protein 2 (MRP2/ABCC2) expression in the liver and kidney. However, the precise mechanisms by which RIF and UDCA act in cholestasis remain unclear. In the present study, we report the effects of chronic administration of both drugs in a patient with Dubin-Johnson syndrome (DJS), an inherited autosomal recessive disorder characterized by the absence of functional MRP2 protein at the canalicular hepatocyte membrane. A novel 974C-->G nonsense mutation was identified in the MRP2 gene sequence from this patient. RIF induced further increase in conjugated bilirubinemia, whereas concomitant administration of RIF and UDCA led to a dramatic rise in serum bile acid concentrations. These biochemical effects, which are in marked contrast to those observed in cholestatic settings, were concomitant with an increased MRP3, but not MRP4, expression on basolateral hepatocyte membrane. Such findings highlight the key role of MRP2 in the pharmacological properties of RIF and UDCA and suggest that both drugs should be used with caution in pathologic settings in which MRP2 expression may be downregulated, as in advanced stage of cholestatic diseases.

Adult↗

PubMed2006

Association between ABO blood group and fibrosis severity in chronic hepatitis C infection.

The progression of fibrosis in hepatitis C virus (HCV) infection is a process in which genes interact with environmental factors. A "clotting process" is involved in fibrogenesis. ABO blood group distribution is associated with thrombotic disease, non-O blood group increasing the risk of venous thrombosis. The aim of the study was to investigate whether ABO blood type contributes to the severity of fibrosis. We studied blood group distribution in 346 French patients with HCV infection who underwent biopsies. The distribution of non-O blood group was 40%, 55%, 62%, 71%, and 73% for the F0, F1, F2, F3 and F4 fibrosis scores, respectively. Non-O blood group was associated with increased severity of fibrosis, even after adjustment on gender, age, duration of infection, and alcohol consumption (odds ratio 1.8, 95% confidence interval 1.0-2.9; P=.04). Non-O blood group is an independent risk factor for the progression of liver fibrosis in HCV infection.

ABO Blood-Group System↗

PubMed2006

Hepatocyte proliferation during liver regeneration is impaired in mice with liver-specific IGF-1R knockout.

Recent evidence indicates that growth hormone (GH) is involved in liver regeneration. To test whether insulin-like growth factor I (IGF-I) mediates this effect, we studied liver regeneration induced by partial hepatectomy in liver-specific IGF type 1 receptor knockout (LIGFREKO) mice. The absence of IGF-1R caused a significant decrease in hepatocyte proliferation in males (-52%), but not in females, as assessed by Ki67 immunohistochemistry. Cyclin D1 and cyclin A protein levels in the livers of LIGFREKO males were only half those in controls, indicating that cyclin induction during liver regeneration is dependent on IGF-1R signaling. Analyzing the signaling cascade initiated by IGF-1R, we observed a lack of IRS-1 induction in LIGFREKO livers. In contrast, the induction of IRS-2 synthesis was similar in LIGFREKO and control groups, suggesting the existence of differential regulation of IRS synthesis during liver regeneration. Regenerating livers from LIGFREKO animals also showed significantly less activated ERKs than controls. Our findings demonstrate that IGF-1R makes a significant contribution to liver regeneration. Using the LIGFREKO model, we provide new evidence that IGF-1R/IRS-1/ERK signaling may be the intracellular pathway controlling the cell cycle via cyclin D1 and cyclin A in the regenerating liver.

Animals↗

PubMed2006

Major role of hepatitis B genotypes in liver fibrosis during coinfection with HIV.

BACKGROUND: Little is know about the determinants of liver fibrosis progression and genomic variability in hepatitis B virus (HBV) in HIV/HBV-coinfected patients. METHODS: A cross-sectional analysis examined common characteristics of HBV infection in an ongoing cohort study of 308 patients with both HIV-1-positive Western blot and plasma HBV surface antigen (HBsAg) seropositivity. Risk factors for liver fibrosis were studied in a subset of 104 patients for whom liver biopsy and complete HBV genomic analysis were available. Analysis was performed by exact multiple regression analysis. RESULTS: Mean age of the study population was 40.3 years, with a ratio male to female of 5.3 and a mean duration of HIV infection of 9.3 years. In the subset of 104 patients, plasma HBV e antigen (HBeAg) in HBV-replicative patients could not be detected in 28.4% and lamivudine-resistant mutants were detected in 67.8%. HBV genotype A was the most frequent genotype (73/104) and 25 patients were infected by the usually rare genotype G. METAVIR fibrosis score was rated F2-F4 in 70 patients. After adjustment for the most common known determinants of liver fibrosis, HBV genotype G [odds ratio (OR), 12.60; 95% confidence interval (CI), 1.72-infinite; P < 0.009], efavirenz exposure (OR, 3.55; 95% CI, 1.14-12.14; P < 0.03), and the duration of HIV infection (3.86; 95% CI, 1.27-12.64; P < 0.01) were strongly associated with the risk of grade F2-F4 fibrosis. CONCLUSION: HBV genotype G is a determinant of liver fibrosis in HIV/HBV-coinfected patients and HBV genotyping should be considered as part of the management of patients with multiple risk factors for rapid progression of liver fibrosis.

Adult↗

PubMed2006

Altered hepatic expression of SREBP-1 and PPARgamma is associated with liver injury in insulin-resistant lipodystrophic HIV-infected patients.

BACKGROUND: HIV-infected patients with HAART-related lipodystrophy are frequently insulin resistant and at risk of non-alcoholic fatty liver disease (NAFLD) with steatohepatitis (NASH). The transcription factors, peroxisome proliferator activated receptors (PPARalpha, PPARgamma1/PPARgamma2) and sterol regulatory element binding proteins (SREBP-1) regulate liver lipid metabolism. Here, we examined whether their expression was modified and related to liver injury in HIV-infected patients. METHODS: Fourteen HAART-treated HIV patients (nine with and five without insulin resistance) who had liver biopsy because of unexplained elevated transaminases were compared with nine non-HIV age-and body mass index-matched patients with NAFLD and 10 controls without steatosis. Hepatic expression of PPARs and SREBP-1 was assessed by real time reverse transcriptase-polymerase chain reaction. RESULTS: Liver histology showed NASH in six of nine insulin-resistant lipodystrophic and two of five non-insulin-resistant HIV patients. Compared with NAFLD or control subjects, expression of SREBP-1 was significantly higher only in HIV-insulin-resistant patients (P = 0.04 and P = 0.02) whereas, compared to controls, HIV-insulin-resistant, HIV-non-insulin-resistant and NAFLD patients had lower expressions of PPARgamma1 (P = 0.03, P = 0.05 and P = 0.01) and PPARgamma2 (P = 0.04, P = 0.05 and P = 0.01). Among HIV patients, the percentage of steatosis was positively correlated with SREBP-1 expression (r = 0.62, P = 0.04) whereas the score of fibrosis was inversely correlated with PPARgamma1 and PPARgamma2 expression (r = -0.57, P = 0.03 and r = -0.6, P = 0.02, respectively). CONCLUSION: Insulin-resistant lipodystrophic HIV-infected patients may develop NASH. Steatosis is associated with overexpression of SREBP-1 and fibrosis with decreased expression of PPARgamma1 and PPARgamma2. These results suggest that altered expression of SREBP-1 and PPARgamma could contribute to the pathogenesis of steatosis and fibronecrotic changes in insulin-resistant lipodystrophic patients.

Adult↗

PubMed2006

Cytoplasmic phospholipase A2 expression in human colon adenocarcinoma is correlated with cyclooxygenase-2 expression and contributes to prostaglandin E2 production.

Cytoplasmic phospholipase A2 (cPLA2) has a key role in prostaglandin production. The role of cPLA2 in intestinal tumorigenesis has been suggested, however, contradictory data are found in the literature. We evaluated cPLA2 and cyclooxygenase-2 (COX-2) protein expression in 65 colon carcinomas by immunohistochemistry, and in eight colorectal cancer cell lines by Western Blot. PGE2 production was evaluated by enzyme-immunoassay in the cell lines. We demonstrate that cPLA2 is overexpressed in approximately 50% of colon cancers and cell lines. cPLA2 expression is correlated with COX-2 expression. Both cPLA2 and COX-2 expressions are important in regard to PGE2 production. Our data suggest that cPLA2 might be involved in colon tumor development.

Adenocarcinoma↗

PubMed2006

Genotype-phenotype correlation in hepatocellular adenoma: new classification and relationship with HCC.

Hepatocellular adenomas are benign tumors that can be difficult to diagnose. To refine their classification, we performed a comprehensive analysis of their genetic, pathological, and clinical features. A multicentric series of 96 liver tumors with a firm or possible diagnosis of hepatocellular adenoma was reviewed by liver pathologists. In all cases, the genes coding for hepatocyte nuclear factor 1alpha (HNF1alpha) and beta-catenin were sequenced. No tumors were mutated in both HNF1alpha and beta-catenin enabling tumors to be classified into 3 groups, according to genotype. Tumors with HNF1alpha mutations formed the most important group of adenomas (44 cases). They were phenotypically characterized by marked steatosis (P < 10(-4)), lack of cytological abnormalities (P < 10(-6)), and no inflammatory infiltrates (P < 10(-4)). In contrast, the group of tumors defined by beta-catenin activation included 13 lesions with frequent cytological abnormalities and pseudo-glandular formation (P < 10(-5)). The third group of tumors without mutation was divided into two subgroups based on the presence of inflammatory infiltrates. The subgroup of tumors consisting of 17 inflammatory lesions, resembled telangiectatic focal nodular hyperplasias, with frequent cytological abnormalities (P = 10(-3)), ductular reaction (P < 10(-2)), and dystrophic vessels (P = .02). In this classification, hepatocellular carcinoma associated with adenoma or borderline lesions between carcinoma and adenoma is found in 46% of the beta-catenin-mutated tumors whereas they are never observed in inflammatory lesions and are rarely found in HNF1alpha mutated tumors (P = .004). In conclusion, the molecular and pathological classification of hepatocellular adenomas permits the identification of strong genotype-phenotype correlations and suggests that adenomas with beta-catenin activation have a higher risk of malignant transformation.

Adenoma, Liver Cell↗

PubMed2006

Assessment of biliary fibrosis by transient elastography in patients with PBC and PSC.

Noninvasive measurement of liver stiffness with transient elastography has been recently validated for the evaluation of hepatic fibrosis in chronic hepatitis C. The current study assessed the diagnostic performance of liver stiffness measurement (LSM) for the determination of fibrosis stage in chronic cholestatic diseases. One hundred one patients with primary biliary cirrhosis (PBC, n=73) or primary sclerosing cholangitis (PSC, n=28) were prospectively enrolled in a multicenter study. All patients underwent liver biopsy (LB) and LSM. Histological and fibrosis stages were assessed on LB by two pathologists. LSM was performed by transient elastography. Efficiency of LSM for the determination of histological and fibrosis stages were determined by a receiver operating characteristics (ROC) curve analysis. Analysis failed in six patients (5.9%) because of unsuitable LB (n=4) or LSM (n=2). Stiffness values ranged from 2.8 to 69.1 kPa (median, 7.8 kPa). LSM was correlated to both fibrosis (Spearman's rho= 0.84, P < .0001) and histological (0.79, P < .0001) stages. These correlations were still found when PBC and PSC patients were analyzed separately. Areas under ROC curves were 0.92 for fibrosis stage (F) > or =2, 0.95 for F > or =3 and 0.96 for F=4. Optimal stiffness cutoff values of 7.3, 9.8, and 17.3 kPa showed F > or =2, F > or =3 and F=4, respectively. LSM and serum hyaluronic acid level were independent parameters associated with extensive fibrosis on LB. In conclusion, transient elastography is a simple and reliable noninvasive means for assessing biliary fibrosis. It should be a promising tool to assess antifibrotic therapies in PBC or PSC.

Adolescent↗

PubMed2005

Long term outcome and response to therapy of primary biliary cirrhosis-autoimmune hepatitis overlap syndrome.

BACKGROUND/AIMS: Whether primary biliary cirrhosis (PBC)-autoimmune hepatitis (AIH) overlap syndrome requires immunosuppressive therapy in addition to ursodeoxycholic acid (UDCA) is a controversial issue. METHODS: Seventeen patients with simultaneous form of strictly defined overlap were followed for 7.5 years. First-line treatment was UDCA alone (UDCA) in 11 and combination of immunosuppressors and UDCA (UDCA + IS) in 6. RESULTS: Characteristics at presentation were not significantly different between the 2 groups. In the UDCA + IS group (f-up 7.3 years), biochemical response in terms of AIH features (ALT<2ULN and IgG < 16 g/L) was achieved in 4/6 and fibrosis did not progress. In the UDCA group, biochemical response was observed in three patients together with stable or decreased fibrosis (f-up 4.5 years) whereas the eight others were non-responders with increased fibrosis in four (f-up 1.6 years). Seven of these eight patients subsequently received combined therapy for 3 years. Biochemical response was obtained in 6/7 and no further increase of fibrosis was demonstrated. Overall, fibrosis progression in non-cirrhotic patients occurred more frequently under UDCA monotherapy (4/8) than under combined therapy (0/6) (P = 0.04). CONCLUSIONS: Combination of UDCA and immunosuppressors appears to be the best therapeutic option for strictly defined PBC-AIH overlap syndrome.

Adult↗

PubMed2005

Increased lung metastasis in transgenic NM23-Null/SV40 mice with hepatocellular carcinoma.

BACKGROUND: The metastasis-suppressing role of the NM23 gene in the metastatic spread of solid tumors is still debated. We examined the role of NM23 in tumor development and metastatic dissemination by using transgenic mice that lack mouse NM23 (NM23-M1) in two mouse models of hepatocellular carcinoma (HCC) that recapitulate all steps of tumor progression. METHODS: We induced HCC in mice that contained (NM23-M1(+/+)) or lacked (NM23-M1(-/-)) NM23-M1 by diethylnitrosamine injection or by a crossing scheme that transferred a transgene that leads to liver expression of simian virus 40 large T antigen (ASV mice). We used microscopic examination and immunohistochemistry to analyze tumor progression. Expression of Nm23 protein isoforms (Nm23-M1 and Nm23-M2) and several tumor markers was analyzed in the primary tumor and in metastases by Western blotting. The statistical significance of differences in the incidence of Nm23-M2 overexpression in null mice relative to that in wild-type mice was tested by a one-sided Fisher's exact test. The statistical significance of differences in the incidence of metastases was examined using one-sided chi-square tests. All other statistical tests were two-sided. RESULTS: In both models, Nm23-M1 and/or Nm23-M2 were overexpressed in the primary liver tumors compared with nontumor liver tissue; however, the lack of the NM23-M1 gene had no effect on primary tumor formation in either model. ASV mice developed pulmonary metastases that were positive for the Hep-Par 1 antibody, which recognizes a specific hepatocyte antigen, whereas the few pulmonary nodules that developed in diethylnitrosamine-injected mice were negative for this antigen. Statistically significantly more ASV/NM23-M1(-/-) mice than ASV/NM23-M1(+/+) mice developed lung metastases (69.2% versus 37.5%; difference = 31.7%, 95% confidence interval = 13.1% to 50.3%; P<.001). In ASV/NM23-M1(+/+) mice, immunohistochemical staining for Nm23-M1 was highly heterogeneous among the primary liver tumors, but weak or negative among lung metastases. CONCLUSIONS: The lack of NM23-M1 expression promotes metastasis in the SV40 animal model of liver carcinogenesis.

Animals↗

PubMed2005

c-myc-induced hepatocarcinogenesis in the absence of IGF-I receptor.

Numerous tumours, including hepatocarcinomas, produce IGFs, and some depend on these growth factors in a paracrine or autocrine fashion. We have shown that c-myc-induced experimental hepatocarcinogenesis is associated with enhanced production of IGF-II. To assess the role of the IGF-I receptor (IGF-IR) in hepatocarcinogenesis, we generated conditional mutant mice that overexpressed c-myc and were knocked out for IGF-IR specifically in the liver. We compared these mice with littermate controls that also overexpressed c-myc but had wild-type IGF-IR alleles. We found that the pretumoral phase, induced by early c-myc expression and characterised by increased cell proliferation, was largely unaffected by the lack of IGF-IR. To our further surprise, hepatocellular carcinomas (HCCs) lacking IGF-IR readily developed and progressed at the same rate as control HCCs. At 9 months, all c-myc transgenic mice displayed well-differentiated multifocal tumours, regardless of whether their livers-and their tumours-were able to produce IGF-IR. Levels of IRS-1 and IRS-2 were elevated in all tumours in the presence or absence of IGF-IR, suggesting that the signalling pathway downstream of IGF-IR is activated via IGF-IR-independent mechanisms in HCC. In conclusion, the deregulation of IGF signalling pathways, which often occurs during liver tumorigenesis, does not necessarily require IGF-IRs, and hepatic IGF-IR alone may not play a determinant role in c-myc-induced hepatocarcinogenesis.

Alleles↗

PubMed2005

Impact of steatosis on progression of fibrosis in patients with mild hepatitis C.

In patients with mild hepatitis C, the usefulness of antiviral therapy is subject of debate, as a low risk for progression of fibrosis is assumed. Several studies have shown that steatosis is a strong and independent predictor of the severity as well as the progression of fibrosis in chronic hepatitis C. Therefore, this study assessed the impact of steatosis on the progression of fibrosis between paired liver biopsies in untreated patients with mild hepatitis on index biopsy. One hundred thirty-five untreated patients (mean age, 38 years; M/F sex ratio, 1.43) with one known risk factor of infection (68 transfusions, 67 injecting drug use) had 2 liver biopsies after a median interval of 61 months (18-158). All had METAVIR score of A1F1 or lower at first liver biopsy. Unequivocal progression of fibrosis was considered if patients had a fibrosis score of 3 or 4 at the second liver biopsy. The probability of progression of fibrosis was estimated by using the Kaplan-Meier method. During follow-up, progression of fibrosis occurred in 21 patients (16%) after a median delay of 65 months. Cumulative probabilities of the progression of fibrosis at 4 and 6 years were 5.2% and 19.8%, respectively. In multivariate analysis, steatosis was the only independent factor predictive of progression of fibrosis (RR, 4.8; CI, 1.3-18.3). Probability of progression of fibrosis was significantly related to the percentage of hepatocytes with steatosis. In conclusion, steatosis is a major determinant of the progression of fibrosis in mild hepatitis C, regardless of the genotype. Our results argue for antiviral treatment in the subgroup of patients with mild hepatitis and steatosis.

Adult↗

PubMed2005

Gefitinib, an EGFR inhibitor, prevents hepatocellular carcinoma development in the rat liver with cirrhosis.

Epidermal growth factor receptor (EGFR) binds transforming growth factor alpha (TGF-alpha) which is mitogenic for hepatocytes. Diverse lines of evidence suggest that activation of the TGF-alpha /EGFR pathway contributes to hepatocellular carcinoma (HCC) formation. Herein, we developed an experimental model of cirrhosis giving rise to HCC and tested the antitumoral effect of gefitinib, a selective EGFR tyrosine kinase inhibitor, in this model. Rats received weekly intraperitoneal injections of diethylnitrosamine (DEN) followed by a 2-week wash-out period that caused cirrhosis in 14 weeks and multifocal HCC in 18 weeks. Hepatocyte proliferation was increased in diseased tissue at 14 weeks compared with control liver and at even higher levels in HCC nodules compared with surrounding diseased tissues at 18 weeks. Increased proliferation was paralleled by upregulation of TGF-alpha messenger RNA expression. A group of DEN-treated rats received daily intraperitoneal injections of gefitinib between weeks 12 and 18. In rats treated with gefitinib, the number of HCC nodules was significantly lower than in untreated rats (18.1 +/- 2.4 vs. 3.7 +/- 0.45; P < .05), while EGFR was activated to a lesser extent in the diseased and tumoral tissues of these animals compared with untreated rats. HCC nodules from both untreated and gefitinib-treated animals displayed insulin-like growth factor 2 overexpression that contributed to tumor formation in treated animals. In conclusion, the blockade of EGFR activity by gefitinib has an antitumoral effect on the development of HCC in DEN-exposed rats, suggesting that it may provide benefit for the chemoprevention of HCC.

Alkylating Agents↗

PubMed2005

Chronic liver injury during obstructive sleep apnea.

Patients with obstructive sleep apnea (OSA) are at risk for the development of fatty liver as a result of being overweight. Several data suggest that OSA per se could be a risk factor of liver injury; ischemic hepatitis during OSA has been reported, and OSA is an independent risk factor for insulin resistance. Therefore, we investigated liver damage and potential mechanisms in 163 consecutive nondrinking patients with nocturnal polysomnographic recording for clinical suspicion of OSA. Serum levels of liver enzymes were measured in all patients. Liver biopsy was offered to patients with elevated liver enzymes. Intrahepatic hypoxia was assessed by the expression of vascular endothelial growth factor (VEGF) on liver biopsy specimens. Severe OSA (apnea-hypopnea index [AHI] > 50/hr) was seen in 27% of patients; 52% had moderate OSA (AHI 10-50/hr), and 21% had no OSA. Overall, 20% had elevated liver enzymes. Independent parameters associated with elevated liver enzymes were body mass index (BMI) (OR: 1.13; CI: 1.03-1.2) and severe OSA (OR: 5.9; CI: 1.2-29). Liver biopsy was performed in 18 of 32 patients with elevated liver enzymes and showed steatohepatitis in 12 cases, associated with fibrosis in 7 cases. Patients with severe OSA were more insulin-resistant according to homeostasis model assessment, had higher percentage of steatosis as well as scores of necrosis and fibrosis, despite similar BMI. Hepatic immunostaining used as an indirect marker of hypoxia was not different between patients with or without severe OSA. In conclusion, severe OSA is a risk factor for elevated liver enzymes and steatohepatitis independent of body weight. Promotion of insulin resistance is probably involved. Further studies are needed to determine whether hypoxia contributes directly to liver injury.

Adult↗

PubMed2005

Acute hepatitis E: a cause of lymphocytic destructive cholangitis.

Lymphocytic destructive cholangitis is a histological pattern associating bile duct intraepithelial lymphocytic infiltration and bile duct epithelial damage. Lymphocytic destructive cholangitis is an important diagnostic feature of primary biliary cirrhosis, but it can also be seen in primary sclerosing cholangitis, autoimmune hepatitis, the so-called overlap syndrome, acute or chronic viral hepatitis C, drug-induced hepatitis, and acute rejection or graft-versus-host disease in liver or bone marrow transplantation. In the present paper we report a case of acute hepatitis with lymphocytic destructive cholangitis on liver biopsy. Clinical and biological examinations showed that the patient had hepatitis E with no other cause of liver disease. Therefore, hepatitis E should be considered as a diagnostic possibility when liver biopsy shows acute hepatitis and lymphocytic destructive cholangitis. The mechanism of bile duct damage in hepatitis E remains unknown.

Acute Disease↗

PubMed2005

Adaptative bile duct proliferative response in experimental bile duct ischemia.

BACKGROUND/AIMS: A rat model of bile duct ischemia was established and used to examine the potential of bile duct proliferation to provide an adaptative response in cholestatic disorders. METHODS: Rats underwent partial or complete arterial deprivation of the liver. Serum biochemical tests, histological analyses and bile secretion measurements were performed at different time points up to 6 weeks after surgery. RESULTS: Rats developed biochemical signs of cholestasis exclusively after complete arterial deprivation. Within 4h, cholangiocytes in these rats showed morphological signs of cell damage. After 48h, they displayed VEGF expression and became proliferative. The proportion of Ki67-labeled cholangiocytes ( approximately 30%) was similar in interlobular bile ducts and periportal ductules. A ductular reaction made of well-formed bile ducts confined to portal tracts developed within 1 week. Bile flow which was initially decreased, was restored at 3 weeks, while the biochemical signs of cholestasis completely resolved at 6 weeks. At this time, the number of bile duct sections was maximal. Fibrosis intensity was also maximal, although moderate (<F2 METAVIR staging) as assessed by Sirius-red staining morphometry. CONCLUSIONS: In the present model of bile duct ischemia, ductular reaction derives from bile ducts of all anatomical compartments, and provides a poorly fibrogenic functional response to biliary dysfunction.

Animals↗