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Cholestasis
Kinds of Cholestasis Selected AbstractsClinical aspects on neonatal cholestasis based on observations at a Swedish tertiary referral centreACTA PAEDIATRICA, Issue 2 2001B Fischler The aim of the study was to investigate the clinical aspects of neonatal cholestasis. The medical records of 85 cholestatic infants were retrospectively reviewed. A majority of the patients were referred from other parts of the country. The most common diagnoses were extrahepatic biliary atresia (n= 30 patients), ,1 -antitrypsin deficiency (n=11) and progressive familial intrahepatic cholestasis (n= 11). On presentation, the biliary atresia group had higher mean serum values of bilirubin, G-GT and cholesterol than the patients with intrahepatic cholestasis, with no significant differences noticed for any other biochemical parameter. A lack of excretion on hepatobiliary scintigraphy was noticed in all investigated patients with biliary atresia, but also in 9 of 34 patients with intrahepatic neonatal cholestasis. There was no statistical correlation between the age at portoenterostomy and the outcome in patients with biliary atresia. However, both the detection of a partial flow on perioperative cholangiogram and the establishment of a non-icteric phase within 6 mo after the portoenterostomy correlated to a good outcome. Eight of 11 patients with progressive familial intrahepatic cholestasis were treated with a biliary diversion procedure, five of eight experienced a sustained cholestatic remission. Conclusions: Progressive familial intrahepatic cholestasis may be a more common cause of neonatal cholestasis in Sweden than reported elsewhere and that the experience with biliary diversion is positive. While early referral in patients with extrahepatic biliary atresia remains important, a portoenterostomy should be attempted also in patients referred after 3 mo of age. [source] Altered membrane glycoprotein targeting in cholestatic hepatocytesEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 5 2010Giuseppa Esterina Liquori Eur J Clin Invest 2010; 40 (5): 393,400 Abstract Background, Hepatocytes are polarized epithelial cells with three morphologically and functionally distinct membrane surfaces: the sinusoidal, lateral and canalicular surface domains. These domains differ from each other in the expression of integral proteins, which concur to their polarized functions. We hypothesize that the cholestasis-induced alterations led to partial loss of hepatocyte polarity. An altered expression of membrane proteins may be indicative of functional disorders. Alkaline liver phosphatase (ALP), one of the most representative plasma membrane glycoproteins in hepatocytes, is expressed at the apical (canalicular) pole of the cell. Because the release of ALP protein in the bloodstream is significantly increased in cholestasis, the enzymatic levels of plasma ALP have major relevance in the diagnosis of cholestatic diseases. Here we assess the cholestasis-induced redistribution of membrane glycoproteins to investigate the ALP release. Materials and methods, We performed enzymatic histochemistry, immunohistochemistry, lectin histochemistry, immunogold and lectin-and immunoblotting studies. Experimental cholestasis was induced in rats by ligation of common bile duct (BDL). Results, The BDL led to altered membrane sialoglycoprotein targeting as well as to ultrastructural and functional disorders. Disarrangement of the microtubular system, thickening of the microfilamentous pericanalicular ectoplasm and disturbance of the vectorial trafficking of membrane glycoprotein containing vesicles were found. Conclusions, Altogether, results indicate that the cholestasis-induced partial loss of hepatocyte cell polarity leads to mistranslocation of ALP to the sinusoidal plasma membrane from where the enzyme is then massively released into the bloodstream. [source] Expression of organic cation transporters OCT1 (SLC22A1) and OCT3 (SLC22A3) is affected by genetic factors and cholestasis in human liver,HEPATOLOGY, Issue 4 2009Anne T. Nies An important function of hepatocytes is the biotransformation and elimination of various drugs, many of which are organic cations and are taken up by organic cation transporters (OCTs) of the solute carrier family 22 (SLC22). Because interindividual variability of OCT expression may affect response to cationic drugs such as metformin, we systematically investigated genetic and nongenetic factors of OCT1/SLC22A1 and OCT3/SLC22A3 expression in human liver. OCT1 and OCT3 expression (messenger RNA [mRNA], protein) was analyzed in liver tissue samples from 150 Caucasian subjects. Hepatic OCTs were localized by way of immunofluorescence microscopy. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and genome-wide single-nucleotide polymorphism microarray technology served to genotype 92 variants in the SLC22A1-A3/OCT1-3 gene cluster. Transport of metformin by recombinant human OCT1 and OCT3 was compared using transfected cells. OCT1 mRNA and protein expression varied 113- and 83-fold, respectively; OCT3 mRNA expression varied 27-fold. OCT1 transcript levels were on average 15-fold higher compared with OCT3. We localized the OCT3 protein to the basolateral hepatocyte membrane and identified metformin as an OCT3 substrate. OCT1 and OCT3 expression are independent of age and sex but were significantly reduced in liver donors diagnosed as cholestatic (P , 0.01). Several haplotypes for OCT1 and OCT3 were identified. Multivariate analysis adjusted for multiple testing showed that only the OCT1-Arg61Cys variant (rs12208357) strongly correlated with decreased OCT1 protein expression (P < 0.0001), and four variants in OCT3 (rs2292334, rs2048327, rs1810126, rs3088442) were associated with reduced OCT3 mRNA levels (P = 0.03). Conclusion: We identified cholestasis and genetic variants as critical determinants for considerable interindividual variability of hepatic OCT1 and OCT3 expression. This indicates consequences for hepatic elimination of and response to OCT substrates such as metformin. (HEPATOLOGY 2009.) [source] The amazing universe of hepatic microstructure,HEPATOLOGY, Issue 2 2009Valeer J. Desmet An informal review is presented by the author of his 50 years of involvement in practice and research in hepatopathology. Some background for the author's attitude and meandering pathway into his professional career serves as introduction to a short discussion of the main topics of his interest and expertise. Histogenesis of liver cancer was the theme of early work for a Ph.D. thesis, the results of which were lost into oblivion due to local rules and circumstances, but were rescued three decades later. His conclusions about the cells of origin of liver cancer remain concordant with the newer concepts in the field after nearly half a century. Studies in the field of chronic hepatitis became a long saga, involving the first classification of this syndrome by "the Gnomes" in 1968, histochemical investigations of viral antigens, lymphocyte subsets and adhesion molecules, and a quarter century later, the creation of a new classification presently in use. Cholestasis was a broadening field in diagnostic entities and involved the study of liver lesions, comprising pathways of bile regurgitation (including reversed secretory polarity of hepatocytes) and so-called ductular reaction. The latter topic has a high importance for the various roles it plays in modulating liver tissue of chronic cholestasis into biliary cirrhosis, and as the territory of hepatic progenitor cells, crucial for liver regeneration in adverse conditions and in development of liver cancer. Study of the embryology of intrahepatic bile ducts helped to clarify the strange appearance of the ducts in "ductal plate configuration" in several conditions, including some forms of biliary atresia with poor prognosis and all varieties of fibrocystic bile duct diseases with "ductal plate malformation" as the basic morphologic lesion. (HEPATOLOGY 2009;50:333,344.) [source] Fractures and avascular necrosis before and after orthotopic liver transplantation: Long-term follow-up and predictive factors,HEPATOLOGY, Issue 4 2007Maureen M. J. Guichelaar With early posttransplant bone loss, orthotopic liver transplantation (OLT) recipients experience a high rate of fracturing and some avascular necrosis (AVN), but little is known about the incidence of and predictive factors for these skeletal complications. We studied 360 consecutive patients who underwent transplantation for primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) and assessed both vertebral and nonvertebral (rib, pelvic, and femur) fractures in a protocolized fashion. Before OLT, 20% of the patients had experienced fracturing, and 1.4% of the patients had experienced AVN. Following OLT, there was a sharp increase in fracturing, with a 30% cumulative incidence of fractures at 1 year and 46% at 8 years after transplantation. In contrast to previous studies, there was a similar incidence of posttransplant vertebral and nonvertebral fractures. The greatest risk factors for posttransplant fracturing were pretransplant fracturing and the severity of osteopenia and posttransplant glucocorticoids. Nine percent of the liver recipients experienced AVN after OLT, and this correlated with pretransplant and posttransplant lipid metabolism, bone disease (bone mineral density and fracturing), and posttransplant glucocorticoids. A novel association between cholestasis and AVN was also identified, the mechanism for which is not known. Conclusion: Fortunately, recent years have seen an increase in the bone mass of liver recipients and, along with this, less fracturing and less AVN. Nonetheless, 25% of patients undergoing OLT for chronic cholestatic liver disease still develop de novo fractures after OLT; this situation demands an ongoing search for effective therapeutic agents for these patients. (HEPATOLOGY 2007.) [source] Mitochondrial hepatopathies: Advances in genetics and pathogenesis,HEPATOLOGY, Issue 6 2007Way S. Lee Hepatic involvement is a common feature in childhood mitochondrial hepatopathies, particularly in the neonatal period. Respiratory chain disorders may present as neonatal acute liver failure, hepatic steatohepatitis, cholestasis, or cirrhosis with chronic liver failure of insidious onset. In recent years, specific molecular defects (mutations in nuclear genes such as SCO1, BCS1L, POLG, DGUOK, and MPV17 and the deletion or rearrangement of mitochondrial DNA) have been identified, with the promise of genetic and prenatal diagnosis. The current treatment of mitochondrial hepatopathies is largely ineffective, and the prognosis is generally poor. The role of liver transplantation in patients with liver failure remains poorly defined because of the systemic nature of the disease, which does not respond to transplantation. Prospective, longitudinal, multicentered studies will be needed to address the gaps in our knowledge in these rare liver diseases. (HEPATOLOGY 2007;45:1555,1565.) [source] Bile acid treatment alters hepatic disease and bile acid transport in peroxisome-deficient PEX2 Zellweger mice,HEPATOLOGY, Issue 4 2007Megan H. Keane The marked deficiency of peroxisomal organelle assembly in the PEX2,/, mouse model for Zellweger syndrome provides a unique opportunity to developmentally and biochemically characterize hepatic disease progression and bile acid products. The postnatal survival of homozygous mutants enabled us to evaluate the response to bile acid replenishment in this disease state. PEX2 mutant liver has severe but transient intrahepatic cholestasis that abates in the early postnatal period and progresses to steatohepatitis by postnatal day 36. We confirmed the expected reduction of mature C24 bile acids, accumulation of C27,bile acid intermediates, and low total bile acid level in liver and bile from these mutant mice. Treating the PEX2,/, mice with bile acids prolonged postnatal survival, alleviated intrahepatic cholestasis and intestinal malabsorption, reduced C27,bile acid intermediate production, and prevented older mutants from developing severe steatohepatitis. However, this therapy exacerbated the degree of hepatic steatosis and worsened the already severe mitochondrial and cellular damage in peroxisome-deficient liver. Both untreated and bile acid,fed PEX2,/, mice accumulated high levels of predominantly unconjugated bile acids in plasma because of altered expression of hepatocyte bile acid transporters. Significant amounts of unconjugated bile acids were also found in the liver and bile of PEX2 mutants, indicating a generalized defect in bile acid conjugation. Conclusion: Peroxisome deficiency widely disturbs bile acid homeostasis and hepatic functioning in mice, and the high sensitivity of the peroxisome-deficient liver to bile acid toxicity limits the effectiveness of bile acid therapy for preventing hepatic disease. (HEPATOLOGY 2007;45:982,997.) [source] Mutual changes of thioredoxin and nitrosothiols during biliary cirrhosis: Results from humans and cholestatic rats,HEPATOLOGY, Issue 2 2007Ignazio Grattagliano Cholestasis is associated with changes in NO metabolism and thiol oxidation. Thioredoxin contributes to regulate vascular tone and intracellular redox status by cleaving nitrosothiols and maintaining ,SH groups. This study investigated the changes in circulating thioredoxin and nitrosothiols and the relationship with protein sulfhydryls (PSH), hepatic concentrations, hyaluronate, and histology in patients with primary biliary cirrhosis (PBC) and in rats with bile duct ligation (BDL). PSH in erythrocytes were significantly decreased in stage III and IV PBC and at day 10 after BDL. Compared with controls, erythrocyte thioredoxin levels were higher in stage I through III PBC and lower in stage IV patients. Serum thioredoxin levels were significantly higher in PBC stages I and II and lower in stages III and IV. Serum nitrosothiols were higher in all PBC patients and inversely related to thioredoxin and hyaluronate. In rats, serum, hepatic, and mitochondrial thioredoxin had initially increased after BDL (day 1-3) and then decreased. After day 7 BDL, nitrosothiols were 10-fold increased in serum and liver, and even higher in mitochondria. In the liver, thioredoxin was inversely related to both nitrosothiols and PSH. In rats, the difference in time average changes from baseline among serum, hepatic, and erythrocyte thioredoxin suggests that most of circulating thioredoxin originates from the liver. Conclusion: Our findings indicate that cholestasis is associated with significant mutual and interrelated changes between circulating and hepatic thioredoxin and nitrosothiols. The increase of hepatic, mitochondrial, and circulating nitrosothiols with ongoing cholestasis suggests an active participation of NO in both liver injury and extrahepatic changes. (HEPATOLOGY 2007;45:331,339.) [source] Linkage between a new splicing site mutation in the MDR3 alias ABCB4 gene and intrahepatic cholestasis of pregnancy,HEPATOLOGY, Issue 1 2007Gudrun Schneider Intrahepatic cholestasis of pregnancy (ICP) is defined as pruritus and elevated bile acid serum concentrations in late pregnancy. Splicing mutations have been described in the multidrug resistance p-glycoprotein 3 (MDR3, ABCB4) gene in up to 20% of ICP women. Pedigrees studied were not large enough for linkage analysis. Ninety-seven family members of a woman with proven ICP were asked about pruritus in earlier pregnancies, birth complications and symptomatic gallstone disease. The familial cholestasis type 1 (FIC1, ATP8B1) gene, bile salt export pump (BSEP, ABCB11) and MDR3 gene were analyzed in 55 relatives. We identified a dominant mode of inheritance with female restricted expression and a new intronic MDR3 mutation c.3486+5G>A resulting in a 54 bp (3465,3518) inframe deletion via cryptic splicing site activation. Linkage analysis of the ICP trait versus this intragenic MDR3 variant yielded a LOD score of 2.48. A Bayesian analysis involving MDR3, BSEP, FIC1 and an unknown locus gave a posterior probability of >0.9966 in favor of MDR3 as causative ICP locus. During the episode of ICP the median ,-glutamyl transpeptidase (,-GT) activity was 10 U/l (95% CI, 6.9 to 14.7 U/l) in the index woman. Four stillbirths were reported in seven heterozygous women (22 pregnancies) and none in five women (14 pregnancies) without MDR3 mutation. Symptomatic gallstone disease was more prevalent in heterozygous relatives (7/21) than in relatives without the mutation (1/34), (P = 0.00341). Conclusion: This study demonstrates that splicing mutations in the MDR3 gene can cause ICP with normal ,-GT and may be associated with stillbirths and gallstone disease. (HEPATOLOGY 2007;45:150,158.) [source] Hepatocellular carcinoma in ten children under five years of age with bile salt export pump deficiency,HEPATOLOGY, Issue 2 2006A. S. Knisely Hepatocellular carcinoma (HCC) is rare in young children. We attempted to see if immunohistochemical and mutational-analysis studies could demonstrate that deficiency of the canalicular bile acid transporter bile salt export pump (BSEP) and mutation in ABCB11, encoding BSEP, underlay progressive familial intrahepatic cholestasis (PFIC),or "neonatal hepatitis" suggesting PFIC,that was associated with HCC in young children. We studied 11 cases of pediatric HCC in the setting of PFIC or "neonatal hepatitis" suggesting PFIC. Archival liver were retrieved and immunostained for BSEP. Mutational analysis of ABCB11 was performed in leukocyte DNA from available patients and parents. Among the 11 nonrelated children studied aged 13-52 months at diagnosis of HCC, 9 (and a full sibling, with neonatal hepatitis suggesting PFIC, of a tenth from whom liver was not available) had immunohistochemical evidence of BSEP deficiency; the eleventh child did not. Mutations in ABCB11 were demonstrated in all patients with BSEP deficiency in whom leukocyte DNA could be studied (n = 7). These mutations were confirmed in the parents (n = 14). With respect to the other 3 children with BSEP deficiency, mutations in ABCB11 were demonstrated in all 5 parents in whom leukocyte DNA could be studied. Thirteen different mutations were found. In conclusion, PFIC associated with BSEP deficiency represents a previously unrecognized risk for HCC in young children. Immunohistochemical evidence of BSEP deficiency correlates well with demonstrable mutation in ABCB11. (HEPATOLOGY 2006;44:478,486.) [source] Comparison of indices of vitamin A status in children with chronic liver disease,HEPATOLOGY, Issue 4 2005Andrew P. Feranchak Malabsorption of fat-soluble vitamins is a major complication of chronic cholestatic liver disease. The most accurate way to assess vitamin A status in children who have cholestasis is unknown. The goal of this study was to assess the accuracy of noninvasive tests to detect vitamin A deficiency. Children with chronic cholestatic liver disease (n = 23) and noncholestatic liver disease (n = 10) were studied. Ten cholestatic patients were identified as vitamin A,deficient based on the relative dose response (RDR). Compared with the RDR, the sensitivity and specificity to detect vitamin A deficiency for each test was, respectively: serum retinol, 90% and 78%; retinol-binding protein (RBP), 40% and 91%; retinol/RBP molar ratio, 60% and 74%; conjunctival impression cytology, 44% and 48%; slit-lamp examination, 20% and 66%; tear film break-up time, 40% and 69%; and Schirmer's test, 20% and 78%. We developed a modified oral RDR via oral coadministration of d-alpha tocopheryl polyethylene glycol-1000 succinate and retinyl palmitate. This test had a sensitivity of 80% and a specificity of 100% to detect vitamin A deficiency. In conclusion, vitamin A deficiency is relatively common in children who have chronic cholestatic liver disease. Our data suggest that serum retinol level as an initial screen followed by confirmation with a modified oral RDR test is the most effective means of identifying vitamin A deficiency in these subjects. (HEPATOLOGY 2005;42:782,792.) [source] Intrahepatic cholestasis of pregnancy and bile acid levels,HEPATOLOGY, Issue 3 2005Loïc Sentilhes M.D. No abstract is available for this article. [source] Can Turner syndrome teach us about the pathogenesis of chronic cholestasis?HEPATOLOGY, Issue 5 2004Piotr Milkiewicz The mechanisms that cause the female predominance of primary biliary cirrhosis (PBC) are uncertain, but the X chromosome includes genes involved in immunological tolerance. We assessed the rate of X monosomy in peripheral white blood cells from 100 women with PBC, 50 with chronic hepatitis C, and 50 healthy controls, by fluorescence in-situ hybridisation. Frequency of X monosomy increased with age in all groups, but was significantly higher in women with PBC than in controls (p<0.0001); age-adjusted back-transformed mean frequencies were 0.050 (95% CI 0.046-0.055) in women with PBC, 0.032 (0.028-0.036) in those with chronic hepatitis C, and 0.028 (0.025-0.032) in controls. We suggest that haploinsufficiency for specific X-linked genes leads to female susceptibility to PBC. [source] Kupffer cell,derived interleukin 10 is responsible for impaired bacterial clearance in bile duct,ligated miceHEPATOLOGY, Issue 2 2004Tetsuya Abe Extrahepatic cholestasis often evokes liver injury with hepatocyte apoptosis, aberrant cytokine production, and,most importantly,postoperative septic complications. To clarify the involvement of aberrant cytokine production and hepatocyte apoptosis in impaired resistance to bacterial infection in obstructive cholestasis, C57BL/6 mice or Fas-mutated lpr mice were inoculated intraperitoneally with 107 colony-forming units of Escherichia coli 5 days after bile duct ligation (BDL) or sham celiotomy. Cytokine levels in sera, liver, and immune cells were assessed via enzyme-linked immunosorbent assay or real-time reverse-transcriptase polymerase chain reaction. BDL mice showed delayed clearance of E. coli in peritoneal cavity, liver, and spleen. Significantly higher levels of serum interleukin (IL) 10 with lower levels of IL-12p40 were observed in BDL mice following E. coli infection. Interferon , production from liver lymphocytes in BDL mice was not increased after E. coli infection either at the transcriptional or protein level. Kupffer cells from BDL mice produced low levels of IL-12p40 and high levels of IL-10 in vitro in response to lipopolysaccharide derived from E. coli. In vivo administration of anti,IL-10 monoclonal antibody ameliorated the course of E. coli infection in BDL mice. Furthermore, BDL- lpr mice did not exhibit impairment in E. coli killing in association with little hepatic injury and a small amount of IL-10 production. In conclusion, increased IL-10 and reciprocally suppressed IL-12 production by Kupffer cells are responsible for deteriorated resistance to bacterial infection in BDL mice. Fas-mediated hepatocyte apoptosis in cholestasis may be involved in the predominant IL-10 production by Kupffer cells. (HEPATOLOGY 2004;40:414,423.) [source] Characterization of mutations in ATP8B1 associated with hereditary cholestasisHEPATOLOGY, Issue 1 2004Leo W. J. Klomp Progressive familial intrahepatic cholestasis (PFIC) and benign recurrent intrahepatic cholestasis (BRIC) are clinically distinct hereditary disorders. PFIC patients suffer from chronic cholestasis and develop liver fibrosis. BRIC patients experience intermittent attacks of cholestasis that resolve spontaneously. Mutations in ATP8B1 (previously FIC1) may result in PFIC or BRIC. We report the genomic organization of ATP8B1 and mutation analyses of 180 families with PFIC or BRIC that identified 54 distinct disease mutations, including 10 mutations predicted to disrupt splicing, 6 nonsense mutations, 11 small insertion or deletion mutations predicted to induce frameshifts, 1 large genomic deletion, 2 small inframe deletions, and 24 missense mutations. Most mutations are rare, occurring in 1,3 families, or are limited to specific populations. Many patients are compound heterozygous for 2 mutations. Mutation type or location correlates overall with clinical severity: missense mutations are more common in BRIC (58% vs. 38% in PFIC), while nonsense, frameshifting, and large deletion mutations are more common in PFIC (41% vs. 16% in BRIC). Some mutations, however, lead to a wide range of phenotypes, from PFIC to BRIC or even no clinical disease. ATP8B1 mutations were detected in 30% and 41%, respectively, of the PFIC and BRIC patients screened. Supplementary material for this article can be found on the HEPATOLOGY website (http://interscience.wiley.com/jpages/0270-9139/suppmat/index.html) and at www.atp8b1-primers.nl (HEPATOLOGY 2004;40:27,38.) [source] The nuclear bile acid receptor FXR as a novel therapeutic target in cholestatic liver diseases: Hype or hope?HEPATOLOGY, Issue 1 2004Michael Trauner M.D. Farnesoid X receptor (FXR) is a bile acid,activated transcription factor that is a member of the nuclear hormone receptor superfamily. FXR-null mice exhibit a phenotype similar to Byler disease, an inherited cholestatic liver disorder. In the liver, activation of FXR induces transcription of transporter genes involved in promoting bile acid clearance and represses genes involved in bile acid biosynthesis. We investigated whether the synthetic FXR agonist GW4064 could protect against cholestatic liver damage in rat models of extrahepatic and intrahepatic cholestasis. In the bile duct ligation and alpha-naphthylisothiocyanate models of cholestasis, GW4064 treatment resulted in significant reductions in serum alanine aminotransferase, aspartate aminotransferase, and lactate dehydrogenase, as well as other markers of liver damage. Rats that received GW4064 treatment also had decreased incidence and extent of necrosis, decreased inflammatory cell infiltration, and decreased bile duct proliferation. Analysis of gene expression in livers from GW4064-treated cholestatic rats revealed decreased expression of bile acid biosynthetic genes and increased expression of genes involved in bile acid transport, including the phospholipid flippase MDR2. The hepatoprotection seen in these animal models by the synthetic FXR agonist suggests FXR agonists may be useful in the treatment of cholestatic liver disease. [source] Effects of proinflammatory cytokines on rat organic anion transporters during toxic liver injury and cholestasisHEPATOLOGY, Issue 2 2003Andreas Geier M.D. Hepatobiliary transporters are down-regulated in toxic and cholestatic liver injury. Cytokines such as tumor necrosis factor , (TNF-,) and interleukin 1, (IL-1,) are attributed to mediate this regulation, but their particular contribution in vivo is still unknown. Thus, we studied the molecular mechanisms by which Ntcp, Oatp1, Oatp2, and Mrp2 are regulated by proinflammatory cytokines during liver injury. Rats were injected intraperitoneally with either carbon tetrachloride or endotoxin. Inactivation of TNF-, and IL-1, was achieved by repetitive intraperitoneal injection of etanercept and anakinra, respectively. Messenger RNA (mRNA) levels of transporters and binding activities as well as nuclear protein levels of Ntcp, Oatp2, and Mrp2 transactivators were determined 20 to 24 hours later. In contrast to IL-1,, TNF-, inactivation alone fully prevented down-regulation of Ntcp, Oatp1, and Oatp2 mRNA as well as reduced binding activity of hepatocyte nuclear factor 1 (HNF-1) in CCl4 -induced toxic injury. In endotoxemia, down-regulation of Mrp2, and partially in case of Ntcp, could be prevented by IL-1, but not TNF-, blockade. However, inactivation of either cytokine led to preservation of HNF1 and partially of retinoid X receptor/retinoic acid receptor (RXR/RAR) binding activity. No effect of anticytokines was seen on pregnane X receptor (PXR) and constitutive androstane receptor (CAR) binding activity as well as nuclear protein mass. In conclusion, TNF-, represents the master cytokine responsible for HNF1-dependent down-regulation of Ntcp, Oatp1, and Oatp2 in CCl4 -induced toxic liver injury. IL-1, predominates in a complex signaling network of Ntcp and Mrp2 regulation in cholestatic liver injury. In contrast to in vitro studies, HNF1 and RXR/RAR-independent mechanisms appear to be more important in regulation of Mrp2 and Ntcp gene expression in endotoxemia. [source] Organic anion transporting polypeptides, cholestasis, and nuclear receptorsHEPATOLOGY, Issue 3 2002Gerd A. Kullak-Ublick No abstract is available for this article. [source] A missense mutation in FIC1 is associated with greenland familial cholestasisHEPATOLOGY, Issue 6 2000Leo W. J. Klomp Greenland familial cholestasis is a severe form of intrahepatic cholestasis described among indigenous Inuit families in Greenland. Patients present with jaundice, pruritus, bleeding episodes, and steatorrhea, and die in childhood due to end-stage liver disease. We investigated the possibility that Greenland familial cholestasis is caused by a mutation in FIC1, the gene defective in patients with progressive familial intrahepatic cholestasis type 1 and many cases of benign recurrent intrahepatic cholestasis. Using single-strand conformation polymorphism analysis and sequencing of the FIC1 exons, a missense mutation, 1660 G,A (D554N), was detected and was shown to segregate with the disease in Inuit patients from Greenland and Canada. Examination of liver specimens from 3 Inuit patients homozygous for this mutation revealed bland canalicular cholestasis and, on transmission electron microscopy, coarsely granular Byler bile, as previously described in patients with progressive familial intrahepatic cholestasis type 1. These data establish Greenland familial cholestasis as a form of progressive familial intrahepatic cholestasis type 1 and further underscore the importance of unimpeded FIC1 activity for normal bile formation. [source] Susceptibility to experimental biliary atresia linked to different hepatic gene expression profiles in two mouse strainsHEPATOLOGY RESEARCH, Issue 2 2010Johannes Leonhardt Aim:, To compare hepatic gene expression during the development of experimental biliary atresia (BA) in two different mouse strains. Methods:, Balb/c mice and C57Black/6 (Black/6) mice were infected with rhesus rotavirus (RRV) postpartum, clinical signs of BA and survival were noted. Liver sections were assessed for cluster of differentiation antigen (CD) 3, CD4 and CD8 expression, and the hepatic virus load was determined. Second, mice of both strains were sacrificed three days after infection. Isolated hepatic RNA was subjected to gene expression analysis using Affymetrix Gene Chip MOE 430 2.0. Results:, The incidence of BA was significantly lower in Black/6 mice compared to Balb/c mice (13.5% vs. 67%, P < 0.05). The mean virus titers were higher in mice with BA compared to mice without BA. Different gene profiles three days after virus infection were noted, with differential expression of 201 genes, including those regulating apoptosis, nucleic acid binding, transport function and particularly the immune response (chemokine C-C motif ligand 2, toll-like receptor 3, CD antigen 14, chemokine (C-X-C motif) ligands 10 and 11). This correlated with a significant increase of CD4 positive cells only in Balb/c mice with BA compared to healthy mice (13.5 vs. 5.0; P < 0.05). Black/6 mice did not exhibit any significant increase of CD3 or CD4 leukocytes despite cholestasis. Conclusion:, The different susceptibility to experimental BA was associated with an increase of CD4 T-cells in the liver of Balb/c mice, which is linked to different gene profiles at the onset of bile duct obstruction. [source] Matrine improves 17,-ethinyl estradiol-induced acute cholestasis in ratsHEPATOLOGY RESEARCH, Issue 11 2009Ying Zhao Aim:, To explore the effects of matrine (MT) on acute intrahepatic cholestasis induced by 17,-ethinyl estradiol (EE) in rats. Methods:, Acute intrahepatic cholestasis in rats were induced by EE, and the effects of MT on acute intrahepatic cholestasis were explored and compared with ursodeoxycholic acid (UDCA) by serum biochemical determination and bile excretion experiments. Results:, The serum biochemical and bile biochemical results indicated that MT and UDCA had notable hepatoprotective effects by counteracting cholestasis induced by EE. The bile flow and the bile excretion of glycocholic acid (GC, a substrate of bile salt export pump [Bsep]), ketoprofen glucuronide (KPG) and rhodamine 123 (Rh123, a substrate of multidrug resistance protein 1 [MDR1]) decreased by EE, were significantly improved after administration of MT. Conclusion:, MT exhibited potential protection against EE-induced acute intrahepatic cholestasis. [source] Matrix metalloproteinase inhibitor, CTS-1027, attenuates liver injury and fibrosis in the bile duct-ligated mouseHEPATOLOGY RESEARCH, Issue 8 2009Alisan Kahraman Aim:, Excessive matrix metalloproteinase (MMP) activity has been implicated in the pathogenesis of acute and chronic liver injury. CTS-1027 is an MMP inhibitor, which has previously been studied in humans as an anti-arthritic agent. Thus, our aim was to assess if CTS-1027 is hepato-protective and anti-fibrogenic during cholestatic liver injury. Methods:, C57/BL6 mice were subjected to bile duct ligation (BDL) for 14 days. Either CTS-1027 or vehicle was administered by gavage. Results:, BDL mice treated with CTS-1027 demonstrated a threefold reduction in hepatocyte apoptosis as assessed by the TUNEL assay or immunohistochemistry for caspase 3/7-positive cells as compared to vehicle-treated BDL animals (P < 0.01). A 70% reduction in bile infarcts, a histological indicator of liver injury, was also observed in CTS-1027-treated BDL animals. These differences could not be ascribed to differences in cholestasis as serum total bilirubin concentrations were nearly identical in the BDL groups of animals. Markers for stellate cell activation (,-smooth muscle actin) and hepatic fibrogenesis (collagen 1) were reduced in CTS-1027 versus vehicle-treated BDL animals (P < 0.05). Overall animal survival following 14 days of BDL was also improved in the group receiving the active drug (P < 0.05). Conclusion:, The BDL mouse, liver injury and hepatic fibrosis are attenuated by treatment with the MMP inhibitor CTS-1027. This drug warrants further evaluation as an anti-fibrogenic drug in hepatic injury. [source] Role of mitogen-activated protein kinases in tauroursodeoxycholic acid-induced bile formation in cholestatic rat liverHEPATOLOGY RESEARCH, Issue 7 2008Gerald Ulrich Denk Aim:, Ursodeoxycholic acid exerts anticholestatic effects in various cholestatic disorders and experimental models of cholestasis. Its taurine conjugate (TUDCA) stimulates bile salt secretion in isolated perfused rat livers (IPRL) under physiological, non-cholestatic conditions, in part by mitogen-activated protein kinase (MAPK)-dependent mechanisms. The role of MAPK in the anticholestatic effect of TUDCA, however, is unclear. Therefore, we studied the role of MAPK in the anticholestatic effect of TUDCA in IPRL and isolated rat hepatocytes (IRH) in taurolithocholic acid (TLCA)-induced cholestasis. Methods:, Bile flow, biliary levels of 2,4-dinitrophenyl-S-glutathione (GS-DNP) as a marker of hepatobiliary organic anion secretion and activity of lactate dehydrogenase (LDH) in hepatovenous effluate as a marker of hepatocellular damage in IPRL perfused with TUDCA and/or TLCA were determined in the presence or absence of MAPK inhibitors. In addition, phosphorylation of Erk 1/2 and p38MAPK induced by TUDCA and/or TLCA was studied by Western immunoblot in IPRL and IRH. Results:, TUDCA-induced bile flow was impaired by the Erk 1/2 inhibitor PD98059 in normal livers (,28%), but not in livers made cholestatic by TLCA. GS-DNP secretion was unaffected by PD98059 under both conditions. TUDCA-induced bile formation and organic anion secretion both in the presence and absence of TLCA were unaffected by the p38MAPK inhibitor SB202190. Erk 1/2 phosphorylation in liver tissue was unchanged after bile salt exposure for 70 min, but was transiently enhanced by TUDCA in IRH. Conclusion:, MAPK do not mediate the anticholestatic effects of TUDCA in TLCA-induced cholestasis. [source] Modulation of sinusoidal and canalicular elimination of bilirubin-glucuronides by rifampicin and other cholestatic drugs in a sandwich culture of rat hepatocytesHEPATOLOGY RESEARCH, Issue 3 2008György Lengyel Aim:, Drug-induced hyperbilirubinemia has been shown to often be derived from modulation of the expression and activity of hepatobiliary transporters. In this study we examined the interactions of some therapeutic agents, which have been shown to cause cholestasis, with the elimination of bilirubin-glucuronides, in order to clarify whether these drugs modify the activity of Mrp2 and Mrp3 directly. Methods:, The modulation of bilirubin-glucuronide elimination with rifampicin, probenecid, indomethacin and benzbromarone was assayed in sandwich cultured rat hepatocytes. Results:, All the drugs studied decreased the canalicular transport, but modified the sinusoidal efflux differently. Rifampicin and probenecid stimulated the sinusoidal efflux, shifting the elimination of bilirubin-glucuronides to the sinusoidal domain (biliary excretion index: 3.9 ± 1.2; 22.7 ± 7.4 vs. 56.6 ± 1.5 and 56.8 ± 5.5). However, the overall elimination of bilirubin-glucuronides did not change significantly. In contrast, indomethacin and benzbromarone inhibited bothtransport processes, resulting in the decrease of the overall bilirubin-glucuronide elimination (61 ± 22; 56 ± 5% of the control). Rifampicin, indomethacin and benzbromarone decreased 5,(6)-carboxy-2,,7,-dichlorofluorescein transport by multidrug resistance-associated protein (Mrp)2 as visualized by confocal laser microscopy and in vesicular transport experiments. Interestingly, rifampicin decreased the MRP3 activity in vesicular transport experiments using 17-beta-estradiol-17-beta-D-glucuronide as substrate, in contrast to that observed in bilirubin-glucuronide transport experiments. Conclusion:, Here we show that the interactions of drugs on hepatobiliary transporter proteins may be identified in vitro in a sandwich culture of hepatocytes, in which canalicular and sinusoidal transport can be studied separately. [source] The role of radixin in altered localization of canalicular conjugate export pump Mrp2 in cholestatic rat liverHEPATOLOGY RESEARCH, Issue 2 2008Hideyuki Kojima Aim:, Cholestasis has been associated with the endocytic retrieval of multidrug resistance protein 2 (Mrp2), but its mechanism is still unclear. Recent studies have indicated that radixin, a cross-linker between the actin filaments and membrane proteins, may be activated by phosphorylation and may be required for the canalicular localization of Mrp2. Methods:, We investigated the role of radixin in the altered localization of Mrp2 in rat models of intrahepatic (ethinyl estradiol treatment) and extrahepatic (bile duct ligation) cholestasis using immunofluorescence microscopy. The changes in localization and expression were analyzed using Scion Image for Windows. Results:, In both models, Mrp2 was localized outside as well as inside the ZO-1 staining, indicating partial dislocation from the canalicular membrane. In contrast to the steep elevation of the immunostaining intensity curves for Mrp2 in the controls, the corresponding curves in both models were broadened and flattened, confirming endocytic retrieval into the hepatocytes. Mrp2 and radixin were colocalized at the canalicular domain in the controls, whereas in both cholestatic rats they were dissociated at some canaliculi, indicating the disturbed colocalization of Mrp2 and radixin in cholestasis. The fluorescence of phosphorylated radixin, an active form of radixin, markedly decreased in both cholestatic models, which was supported by the reduced peak fluorescence intensities. Conclusion:, The disturbed colocalization of Mrp2 and radixin may contribute to the endocytic retrieval of Mrp2 in cholestasis due to the failure to anchor Mrp2 in the canalicular membrane, in which the phosphorylated radixin may play a major role. [source] Potentiation of isoniazid-induced liver toxicity by rifampicin in a combinational therapy of antitubercular drugs (rifampicin, isoniazid and pyrazinamide) in Wistar rats: A toxicity profile studyHEPATOLOGY RESEARCH, Issue 10 2007Sheikh Abdullah Tasduq Aim:, Biochemical characterization of long-term toxic manifestations of anti-tubercular (anti-TB) drugs , rifampicin (RIF), isoniazid (INH) and pyrazinamide (PZA) , individually and in two combinations: (i) RIF + INH, and (ii) RIF + INH + PZA in Wistar rats. Methods:, Animals received anti-TB drugs , alone or in combination , once daily p.o. for up to 90 days (doses, in mg/kg: RIF, 250; INH, 50; PZA, 100). Assays for alanine aminotransferase (ALT), alkaline phosphatase (ALP), bilirubin (serum) and lipid peroxidation (LPO), glutathione (GSH), glutathione peroxidase (GPx), catalase, Na+K+-ATPase and CYP 2E1 (liver) were performed to assess liver toxicity. Clinical biochemistry was done by commercial kits. Determinations were made at 0, 15, 30 and 90 days of treatment schedule. Results:, Anti-TB drugs-treated animals showed abnormal rises or falls (>1.5,2 fold) in the serum/liver parameters. Mild hyperlipidemia, hypercholesterolemia and hyperuricemia were the other pathologies. Of all the treated groups, INHalone or in combination with other drugs produced a progressive enhancement of toxicity over 15,90 days. The in vivo results were further supported by in vitro results (MTT assay, GSH and LPO) in primary cultures of rat hepatocyte. Results indicated that anti-TB drugs in combination: (i) caused membrane damage resulting in leakage of ALT, ALP and bilirubin; (ii) caused imbalance in endogenous enzymatic oxidant,antioxidant defense via increased lipid peroxidation and in glutathione homeostasis; and (iii) enhanced the CYP 2E1-mediated bioactivation mechanism. Conclusion:, Toxicity manifestations seemed to be heptocytic injury targeted at hepatocytes, bile ducts or sinusoidal cells related to hepatitis and primary biliary cholestasis. [source] Fibrate for treatment of primary biliary cirrhosisHEPATOLOGY RESEARCH, Issue 2007Shinji Iwasaki Recent studies of the effectiveness of ursodeoxycholic acid (UDCA) therapy in patients with primary biliary cirrhosis (PBC) reported that UDCA therapy did not necessarily stop the progression of liver fibrosis in all patients, even those with early stage PBC. Thus, there is a need for more effective treatments that could prevent asymptomatic PBC from progressing to the icteric stage. Bezafibrate is effective in approximately two-thirds of non-icteric patients who have not shown a complete response to UDCA. Serum bilirubin, aspartate aminotransferase and ,-guanosine 5,-triphosphate levelswere significantly lower in patients who responded to additional bezafibrate on univariate analysis. The putative mechanism by which bezafibrate acts in cholestasis is by increasing phospholipid output into bile, which forms micelles with the hydrophobic bile acid that reduces its toxicity. [source] Bezafibrate induces multidrug-resistance P-Glycoprotein 3 expression in cultured human hepatocytes and humanized livers of chimeric miceHEPATOLOGY RESEARCH, Issue 7 2007Junichi Shoda Aim and Methods: , A decreased function of multidrug-resistance 3 P-glycoprotein (MDR3), limiting the rate of biliary phospholipid secretion, predisposes individuals to cholestasis and/or cholangitis. Fibrates induce the expression of mdr2 (homolog of human MDR3) in rodents. To investigate the effects of bezafibrate (BF) on the expression levels of MDR3 in cultured human hepatocytes and human livers, the amount of protein and subcellular localization of MDR3 was assessed in HepG2 cells treated with BF and humanized livers of BF-treated chimeric mice. Results:, In HepG2 cells, while treatment with BF did not increase the protein levels of MDR3, the treatment caused a redistribution of MDR3 in the bile canaliculi. In humanized livers of chimeric mice, oral administration of BF induced a large increase in the protein amount of MDR3 and its redistribution in the bile canaliculi. Moreover, the modulatory effects of BF on key factors involved in hepatic cholesterol and bile acid metabolism in human subjects were traced in the humanized livers of BF-treated chimeric mice. Conclusion:, BF causes an induction of MDR3 expression in human livers. This provides a rationale for the beneficial role of BF in improving cholestasis and/or cholangitis associated with defective MDR3 expression and function in various types of cholestatic hepatobiliary diseases. [source] A case of acute hepatitis E associated with multidrug hypersensitivity and cytomegalovirus reactivationHEPATOLOGY RESEARCH, Issue 2 2007Yasuhiro Takikawa A 65-year-old Japanese man was hospitalized because of acute hepatitis and severe cholestasis due to hepatitis E virus (HEV) infection combined with a drug reaction to a cold preparation. He died of disseminated intravascular coagulation and severe intestinal bleeding due to systemic cytomegalovirus reactivation following the development of severe eruptions with marked eosinophilia due to drug hypersensitivity to taurine and ursodeoxycholate preparations. The close interaction between viral infection or reactivation and drug hypersensitivity was considered as a pathophysiology in this case, which emphasizes the need for further study of the immunological mechanism of the interaction. [source] Willan's itch and other causes of pruritus in the elderlyINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 4 2005Jon R. Ward MD Itch in the elderly presents a diagnostic and therapeutic challenge. A thorough history, review of systems, and physical examination are critical to determining its cause. Examination of the skin may be misleading. There are frequently only secondary lesions, eczematous changes, lichenification, and excoriation, which may be misdiagnosed as a primary dermatitis. Xerosis may be the cause, but it is sometimes merely coincidental. If primary lesions are present, a skin biopsy can enable a diagnosis to be made. Systemic causes of itch, such as cholestasis, uremia, hyperthyroidism, medications, or lymphoma, must be considered. If the cause remains elusive, idiopathic itching of the elderly or so-called "senile pruritus" may be considered. However, we propose to discard the term "senile pruritus", which can be offensive and frightening. We propose to replace it with "Willan's itch". Robert Willan (1757,1812) is honored as one of the founders of modern dermatology thanks to his book, On Cutaneous Diseases, and its morphological approach to skin disease. He was probably the first to give a good clinical description of itching in the elderly. The diagnosis of Willan's itch should be reserved for generalized pruritus in the absence of xerosis or other recognizable cause. The pathophysiology of this form of pruritus is poorly understood, but it is likely that age-related changes of the skin, cutaneous nerves, and other parts of the nervous system play a role. Anecdotal and limited data suggest that gabapentin, cutaneous field stimulation, serotonin antagonists, and ultraviolet B phototherapy may attenuate itch in some of these patients. [source] | ||||||||||||||||||||||||||||||||||