Gut dysbiosis associated with clinical prognosis of patients with primary biliary cholangitis.

AIM: Although some relationships between gut microbiota and liver diseases have been reported, it remains uncertain whether changes in gut microbiota owing to differences in race, food and living environment have similar effects. Response to ursodeoxycholic acid (UDCA) may predict the long-term prognosis of patients with primary biliary cholangitis (PBC); however, little is known about the significance of the gut microbiome in patients with PBC. We elucidated the relationships among clinical profiles, biochemical response to UDCA and gut microbiome composition in patients with PBC. METHODS: Fecal samples from 76 patients with PBC treated at our hospital were collected; patients whose UDCA intake period was <1 year were excluded. The microbiome structures of patients were determined using 16S ribosomal RNA gene sequencing and were statistically compared with those of healthy subjects. The structures of patients in the UDCA responder (n = 43) and non-responder (n = 30) groups were compared according to the Nara criteria (reduction rate of gamma-glutamyl transpeptidase, ≥69%, after 1 year). RESULTS: Compared with healthy subjects, bacterial diversity was lower in patients with PBC, with a decreased abundance of the order Clostridiales and increased abundance of Lactobacillales. The UDCA non-responder group had a significantly lower population of the genus Faecalibacterium, known as butyrate-producing beneficial bacteria (P < 0.05), although no significant differences in gender, body mass index, medicated drugs or other serological data were indicated between these two groups. CONCLUSIONS: Gut dysbiosis with loss of beneficial Clostridiales commensals was observed in patients with PBC. Decrease in Faecalibacterium abundance might predict the long-term prognosis of patients with PBC.

Direct renin inhibitor, aliskiren, attenuates the progression of non-alcoholic steatohepatitis in the rat model.

AIM: Renin is a rate-limiting enzyme of the renin-angiotensin system (RAS), and several reports have shown that renin plays an important role in several pathological processes. Although RAS is known to play a pivotal role in the progression of non-alcoholic steatohepatitis (NASH), the role of renin is still obscure. The aim of the current study was to examine the effect of the clinically used direct renin inhibitor (DRI), aliskiren, on the progression of NASH in a rat model. METHODS: The effects of DRI on the choline-deficient L-amino acid-defined (CDAA) diet-induced rat NASH model was examined in conjunction with the activated hepatic stellate cells (Ac-HSC) and neovascularization, both of which are known to play important roles in liver fibrosis development and hepatocarcinogenesis, respectively. RESULTS: DRI exerted a marked inhibitory effect against liver fibrosis development and glutathione-S-transferase placental form (GST-P) positive preneoplastic lesions along with suppression of the Ac-HSC and neovascularization in a dose-dependent manner. DRI also inhibited the hepatic expressions of transforming growth factor-beta 1 (TGF-beta 1), angiotensin-II (AT-II) and vascular endothelial growth factor (VEGF). These results indicated that renin played a pivotal role in the liver fibrosis development and hepatocarcinogenesis of NASH. CONCLUSION: Because DRI is already widely used in the clinical practice with safety, this drug may represent a potential new strategy against the progression of NASH in the future.

Dual blockade of angiotensin-II and aldosterone suppresses the progression of a non-diabetic rat model of steatohepatitis.

AIM: Both angiotensin-II (AT-II) and aldosterone (Ald) play pivotal roles in the pathogenesis of diseases in several organs including the liver. We previously reported that suppression of AT-II and Ald with angiotensin-converting enzyme inhibitor (ACE-I) and selective Ald blocker (SAB), respectively, attenuated the rat liver fibrogenesis and hepatocarcinogenesis. The aim of our current study was to elucidate the combined effects of ACE-I and SAB in the progression of a non-diabetic rat model of steatohepatitis, and the possible mechanisms involved. METHODS: In the choline-deficient L-amino acid-defined (CDAA) diet-induced model, the effects of ACE-I and SAB on liver fibrosis development and hepatocarcinogenesis were elucidated, especially in conjunction with neovascularization. RESULTS: Treatment with both ACE-I and SAB suppressed the development of liver fibrosis and glutathione-S-transferase placental form (GST-P) positive pre-neoplastic lesions. The combined treatment with both agents exerted more inhibitory effects as compared with either a single agent along with suppression of the activated hepatic stellate cells (Ac-HSC) and neovascularization, both of which play important roles in these processes. Our in vitro study showed that AT-II type 1 receptor blocker (ARB) and SAB inhibited Ac-HSC proliferation and in vitro angiogenesis along with suppression of the in vivo studies. CONCLUSION: Dual blockade of AT-II and Ald suppresses the progression of a non-diabetic rat model of steatohepatitis. Because both agents are widely and safely used in clinical practice, this combination therapy could be an effective new strategy against steatohepatitis in the future.

Cross talk between toll-like receptor-4 signaling and angiotensin-II in liver fibrosis development in the rat model of non-alcoholic steatohepatitis.

BACKGROUND AND AIM: The innate immune system, including toll-like receptor-4 (TLR4) signaling cascade and angiotensin-II (AT-II) play important roles in the progression of liver fibrosis development; the cross talk between TLR4 and AT-II has not been elucidated yet. The aim of the current study was to elucidate the effect of AT-II type 1 receptor blocker (ARB), on the liver fibrosis development, especially in conjunction with the interaction of TLR4 and AT-II in the rat model of non-alcoholic steatohepatitis. METHODS: Fischer 344 rats were fed a choline-deficient, L-amino-acid-defined diet for 8 weeks and the effects of losartan were elucidated in conjunction with activated hepatic stellate cells (Ac-HSC) activation, TLR4, nuclear factor-κB (NF-κB), and transforming growth factor-ß (TGF-ß) expressions. In vitro study was carried out to elucidate the effect of AT-II on several indices including TLR4, myeloid differentiation factor 88, NF-κB, and TGF-ß expressions in the rat HSC. RESULTS: ARB markedly inhibited liver fibrosis development along with suppression of the number of Ac-HSC and TGF-ß. These inhibitory effects of ARB were almost in parallel with suppression of the hepatic TLR4 and NF-κB expressions. This in vitro study showed that AT-II significantly augmented the TLR4 expression in a dose- and time-dependent manner via AT-II type 1 receptor in the Ac-HSC. AT-II also augmented the lipopolysaccharide-induced myeloid differentiation factor 88 (MyD88), NF-κB, and TGF-ß and these increments were attenuated by treatment with ARB. CONCLUSIONS: These studies indicated that the cross talk between TLR4 signaling cascade and AT-II plays a pivotal role in liver fibrosis development in non-alcoholic steatohepatitis.

The effect of inflammatory cytokines in alcoholic liver disease.

Alcohol is the most common cause of liver disease in the world. Chronic alcohol consumption leads to hepatocellular injury and liver inflammation. Inflammatory cytokines, such as TNF-α and IFN-γ, induce liver injury in the rat model of alcoholic liver disease (ALD). Hepatoprotective cytokines, such as IL-6, and anti-inflammatory cytokines, such as IL-10, are also associated with ALD. IL-6 improves ALD via activation of the signal transducer and activator of transcription 3 (STAT3) and the subsequent induction of a variety of hepatoprotective genes in hepatocytes. IL-10 inhibits alcoholic liver inflammation via activation of STAT3 in Kupffer cells and the subsequent inhibition of liver inflammation. Alcohol consumption promotes liver inflammation by increasing translocation of gut-derived endotoxins to the portal circulation and activating Kupffer cells through the LPS/Toll-like receptor (TLR) 4 pathways. Oxidative stress and microflora products are also associated with ALD. Interactions between pro- and anti-inflammatory cytokines and other cytokines and chemokines are likely to play important roles in the development of ALD. The present study aims to conduct a systemic review of ALD from the aspect of inflammation.

Liver Biopsy-confirmed Primary Hepatic Amyloidosis with Only Jaundice As the Initial Symptom: An Autopsy Case Report.

Amyloidosis causes various symptoms in many organs of the body, but amyloidosis that presents with liver damage alone has never been reported. We treated an 83-year-old man with amyloidosis who presented with liver damage alone. The liver damage in this patient was histologically proven to be liver amyloidosis. The administration of bortezomib and dexamethasone was not effective, so he rapidly died of liver failure. An aggressive liver biopsy should be considered when unexplained jaundice is observed.

Intraductal papillary-mucinous carcinoma with portal vein tumor thrombus and multifocal liver metastasis: An autopsy case.

The prognosis of intraductal papillary-mucinous neoplasm is superior to that of conventional pancreatic ductal adenocarcinoma. Only a few advanced cases of intraductal papillary-mucinous carcinoma (IPMC) have been reported to date. We herein report the case of a 78-year-old male patient with advanced pancreatobiliary type IPMC with portal vein invasion and liver metastasis. The IPMC invaded the portal vein to form a tumor thrombus and it also metastasized to the liver via the portal vein. After receiving best supportive care, the patient succumbed to the disease following an exacerbation of IPMC 90 days after the initial presentation. On autopsy, a very long tumor thrombus was identified, along with liver metastatic lesions, which had retained the structure of the primary IPMC on histological examination.

Identification of the Response-Related Biomarker of Bimonthly Hepatic Arterial Infusion Chemotherapy.

Despite the availability of molecularly targeted agents for advanced hepatocellular carcinoma (aHCC), these are limited to compensated cirrhotic patients, and concerns about decreased hepatic functional reserve (HFR) and unknown adverse events, which may affect long-term survival, remain unaddressed. In this study, we enrolled 96 aHCC patients treated with bimonthly hepatic arterial infusion chemotherapy (B-HAIC) with cisplatin or sorafenib monotherapy (oral sorafenib 400 mg twice daily) not only to demonstrate its efficacy and significance but also to indicate preferable candidates by setting a response-related biomarker. Differences in treatment had no significant effect on overall survival (OS). The response rate in patients treated with B-HAIC was relatively higher than those treated with sorafenib. HFR was well maintained over the treatment course with B-HAIC, while it was significantly impaired with sorafenib. By employing multivariate analysis, we found negative trends between progression-free survival (PFS) periods and serum levels of alpha fetoprotein as well as des-gamma-carboxy prothrombin (DCP). In addition, a logistic regression analysis of the relationship between serum DCP levels and PFS periods over 420 days (14 months) showed that the PFS periods of patients with higher DCP was significantly shorter than those of patients with lower DCP (p = 0.02). Subsequently, the present study demonstrated the efficacy and safety of B-HAIC and identified a predictor of unpreferable patients. Based on these results, B-HAIC might be an alternative treatment after the implementation of new molecularly targeted therapies.

Zinc Administration and Improved Serum Markers of Hepatic Fibrosis in Patients with Autoimmune Hepatitis.

AIM: The aim of the present study is to investigate the effect of long-term zinc supplementation, which is important for the activation of various enzymes that contribute to antioxidant and antifibrotic activities, on the improvement of serum fibrotic markers in patients with autoimmune hepatitis (AIH). METHODS: A total of 38 patients with AIH under regular treatment at our hospital who provided their consent for being treated with polaprezinc (75 mg twice daily) were included and classified into 2 groups: the patients with zinc elevation (n = 27) and the patients without zinc elevation (n = 11). Serum biomarker of fibrosis, protein expression levels of matrix metalloproteinases (MMPs), and their inhibitors (TIMPs) were evaluated. RESULTS: A significant difference was found between the variability of serum procollagen type Ⅲ and collagen type Ⅳ-7S between the 2 groups before and after zinc administration for more than 24 months (p = 0.043 and p = 0.049). In the patients with zinc elevation, no significant changes were found in collagenase (MMP-1 and MMP-13) before and after zinc administration, whereas a significant increase in the expression of gelatinase (MMP-2 and MMP-9) was found after administration (p = 0.021 and p = 0.005). As for the relative ratio of MMPs to TIMPs, only MMP-9 to TIMP-1 showed a significant increase (p = 0.004). CONCLUSIONS: Long-term treatment with polaprezinc has been demonstrated to safely improve serum fibrosis indices through increases in MMP-2/-9 and MMP-9/TIMP-1 and is expected to be well combined with direct antifibrotic therapies such as molecularly targeted agents.

Novel oral plasminogen activator inhibitor­1 inhibitor TM5275 attenuates hepatic fibrosis under metabolic syndrome via suppression of activated hepatic stellate cells in rats.

An orally bioavailable small molecule inhibitor of plasminogen activator inhibitor­1 (PAI­1) is currently being clinically assessed as a novel antithrombotic agent. Although PAI­1 is known to serve a key role in the pathogenesis of metabolic syndrome (MetS) including nonalcoholic steatohepatitis (NASH), the pharmacological action of an oral PAI­1 inhibitor against the development of MetS­related liver fibrosis remains unclear. The current study was designed to explicate the effect of TM5275, an oral PAI­1 inhibitor, on MetS­related hepatic fibrogenesis. The in vivo antifibrotic effect of orally administered TM5275 was investigated in two different rat MetS models. Fischer 344 rats received a choline­deficient L­amino­acid­defined diet for 12 weeks to induce steatohepatitis with development of severe hepatic fibrosis. Otsuka Long­Evans Tokushima Fatty rats, used to model congenital diabetes, underwent intraperitoneal injection of porcine serum for 6 weeks to induce hepatic fibrosis under diabetic conditions. In each experimental model, TM5275 markedly ameliorated the development of hepatic fibrosis and suppressed the proliferation of activated hepatic stellate cells (HSCs). Additionally, the hepatic production of tumor growth factor (TGF)­ß1 and total collagen was suppressed. In vitro assays revealed that TGF­ß1 stimulated the upregulation of Serpine1 mRNA expression, which was inhibited by TM5275 treatment in cultured HSC­T6 cells, a rat HSC cell line. Furthermore, TM5275 substantially attenuated the TGF­ß1­stimulated proliferative and fibrogenic activity of HSCs by inhibiting AKT phosphorylation. Collectively, TM5275 demonstrated an antifibrotic effect on liver fibrosis in different rat MetS models, suppressing TGF­ß1­induced HSC proliferation and collagen synthesis. Thus, PAI­1 inhibitors may serve as effective future therapeutic agents against NASH­based hepatic fibrosis.

A Histologically Proven Case of Autoimmune Hepatitis with Eosinophilic Fasciitis.

Both autoimmune hepatitis (AIH) and eosinophilic fasciitis (EF) are known to be complicated by other autoimmune diseases. However, AIH complicated by EF has never been reported. We experienced a 58-year-old man with AIH complicated by EF. He was admitted to our hospital with acute hepatic injury and edema of the legs in April 201X. The etiologies of these symptoms were histologically proven as AIH and EF. The administration of prednisolone (PSL) drastically improved his liver injury and edema of the legs. When we make a diagnosis of AIH, we should carefully evaluate the physical findings, including the appearance of the legs, in order to detect other coexisting autoimmune diseases.

Bi-monthly hepatic arterial infusion chemotherapy as a novel strategy for advanced hepatocellular carcinoma in decompensated cirrhotic patients.

BACKGROUND AND AIM: We previously reported the comparable efficacy of bi-monthly hepatic arterial infusion chemotherapy (B-HAIC) to that of sorafenib chemotherapy for the treatment of advanced hepatocellular carcinoma (aHCC) in patients with compensated cirrhosis. In this study, we demonstrate the efficacy of B-HAIC in patients with decompensated cirrhosis. METHODS: Forty-five patients with aHCC refractory to transcatheter arterial chemo-embolization (TACE) were treated with B-HAIC and were divided into two groups according to hepatic functional reserve (Child-Pugh grade). Overall survival period, treatment response, and adverse events in each group were analyzed. RESULTS: Efficacy and disease control rates in the Child-Pugh B group (n=24; 21% and 71%, respectively) were not significantly impaired compared the Child-Pugh A group (n=21; 38% and 67%, respectively). Median survival time and survival rate at 12 months in the Child-Pugh B group were 422 days and 58.3%, respectively, whereas those in the ChildPugh A group were 567 days and 70.8%, respectively. Importantly, the hepatic functional reserve of patients did not worsen in either group during the treatment period. Furthermore, the occurrence rate of adverse events leading to discontinuation of anti-tumor treatment was not significantly increased in the Child-Pugh B group. CONCLUSION: Given the preservation of hepatic functional reserve afforded by B-HAIC chemotherapy in patients with decompensated cirrhosis, B-HAIC might be an acceptable alternative strategy for aHCC patients who do not respond to TACE.

Efficacy of bi-monthly hepatic arterial infusion chemotherapy for advanced hepatocellular carcinoma.

BACKGROUND: Even though the Barcelona Clinic Liver Cancer (BCLC) staging system is widely accepted, controversies on the management of hepatocellular carcinoma (HCC) still exist. We evaluated the efficacy of an approach with repeated hepatic arterial infusion chemotherapy (HAIC) given at eight-week intervals for the treatment of advanced HCC. METHODS: Of the 66 compensated cirrhotic patients with advanced HCC refractory to transcatheter arterial chemo-embolization (TACE) enrolled in our study, 21 were treated by bi-monthly hepatic arterial infusion chemotherapy (B-HAIC) and the rest by sorafenib. The overall survival periods, curative responses, and adverse events in each group were retrospectively analyzed. RESULTS: The efficacy rate was significantly higher in the B-HAIC group (38%, 11%, P<0.05). The median survival time and the survival rate at 12 months in the B-HAIC group were 567 days and 70.8%, and those in the sorafenib group were 366 days and 47.6%, respectively. Thus, our data suggests that the B-HAIC treatment is not inferior to sorafenib for the treatment of advanced HCC in compensated cirrhotic patients. Furthermore, the occurrence of serious adverse events leading to discontinuation of treatment was less frequent in the B-HAIC group. CONCLUSIONS: Given the hepatic function reserve preservation afforded by the B-HAIC treatment in our experience, we suggest that B-HAIC should be considered an alternative strategy for advanced HCC patients who do not respond to TACE.

Periostin cross­reacts with the renin­angiotensin system during liver fibrosis development.

Periostin is a 90­kDa extracellular matrix protein, which is secreted primarily from fibroblasts and is expressed in the lungs, kidneys and heart valves. Angiotensin II (AT­II) serves pivotal roles in the pathogenesis of several diseases with accompanying fibrosis, including chronic liver diseases. AT­II induces periostin expression by regulating transforming growth factor­ß1 (TGF­ß1)/Smad signaling during cardiac fibrosis. The aim of the present study was to investigate the interaction between AT­II and periostin during liver fibrosis development. Fischer 344 rats were fed a choline­deficient L­amino­acid (CDAA)­defined diet for 12 weeks to simulate the development of steatohepatitis with liver fibrosis. Losartan, an AT­II type I receptor blocker, was administered to inhibit the effect of AT­II. The therapeutic effect of losartan on hepatic fibrosis development and on periostin expression was then evaluated. Several in vitro experiments were performed to examine the mechanisms underlying the interaction between AT­II and periostin in activated hepatic stellate cells (Ac­HSCs). Treatment with losartan suppressed the development of liver fibrosis induced by the CDAA diet, and reduced hepatic periostin expression. In addition, losartan treatment suppressed hepatic Ac­HSC expansion and hepatic TGF­ß1 expression. In vitro analysis using LX2 HSC cells indicated that AT­II can augment TGF­ß1 and collagen type I α1 mRNA expression via periostin expression, suggesting that the interaction between AT­II and periostin may serve a role in liver fibrosis development. In conclusion, blockade of AT­II­induced periostin may suppress the progression of liver fibrosis development.

Predisposing factors for hepatocellular carcinoma recurrence following initial remission after transcatheter arterial chemoembolization.

Hepatocellular carcinoma (HCC) is prone to recurrence following curative treatment. The purpose of the present study was to identify the predisposing factors of HCC recurrence following complete remission achieved by transarterial chemoembolization (TACE). A retrospective cohort study of 70 consecutive patients with HCC who underwent TACE as the initial treatment was conducted. The patients were divided into two groups according to their 1-year disease-free survival (DFS) status; the early recurrence group (ER group; n=32), with HCC recurring within 1 year of initial TACE; and the non-early recurrence group (NER group; n=38), who did not experience recurrence within 1 year. The parameters identified as significantly associated with DFS time on univariate analysis were aspartate aminotransferase (AST), alanine aminotransferase and α-fetoprotein levels, as well as the tumor number (P=0.003, P=0.027, P=0.002 and P=0.005, respectively). Multivariate analysis revealed that AST levels and tumor number were significantly associated with a shorter DFS period (P=0.009 and P=0.038, respectively). The Mantel-Haenszel test revealed a significant trend of decreasing DFS with increasing tumor number. Among the patients with HCC in the ER group, locoregional recurrence occurred more frequently in those who received TACE alone compared with those treated with TACE combined with radiofrequency ablation treatment. In summary, multinodularity of HCC is the most potent predictive factor for the recurrence of HCC within 1 year of initial TACE.

Cecal Tuberculosis Mimicking Submucosal Tumor.

A 41-year-old man presented with abdominal fullness in late August 2012. Abdominal CT showed ileus caused by stenosis of the ileum and an enlargement of the ileocecal lymph nodes. Colonoscopy showed a steep elevated protruding tumor in the cecum, with multiple ulcerative lesions on top. A pathological analysis of the lesions confirmed chronic inflammatory infiltration and epithelioid granuloma. The findings of a tuberculin skin test and QuantiFERON-TB-Gold test were positive. As a result, we treated the patient for tuberculosis of the cecum. After 4 months of treatment, colonoscopy confirmed the disappearance of the tumor. In conclusion, intestinal tuberculosis should be considered in the differential diagnosis when protruding lesions appear in the cecum.

Ipragliflozin, a sodium-glucose cotransporter 2 inhibitor, ameliorates the development of liver fibrosis in diabetic Otsuka Long-Evans Tokushima fatty rats.

BACKGROUND: It is widely understood that insulin resistance (IR) critically correlates with the development of liver fibrosis in several types of chronic liver injuries. Several experiments have proved that anti-IR treatment can alleviate liver fibrosis. Sodium-glucose cotransporter 2 (SGLT2) inhibitors comprise a new class of antidiabetic agents that inhibit glucose reabsorption in the renal proximal tubules, improving IR. The aim of this study was to elucidate the effect of an SGLT2 inhibitor on the development of liver fibrosis using obese diabetic Otsuka Long-Evans Tokushima fatty (OLETF) rats and their littermate nondiabetic Long-Evans Tokushima Otsuka (LETO) rats. METHODS: Male OLETF and LETO rats were intraperitoneally injected with porcine serum twice a week for 12 weeks to augment liver fibrogenesis. Different concentrations of ipragliflozin (3 and 6 mg/kg) were orally administered during the experimental period. Serological and histological data were examined at the end of the experimental period. The direct effect of ipragliflozin on the proliferation of a human hepatic stellate cell (HSC) line, LX-2, was also evaluated in vitro. RESULTS: OLETF rats, but not LETO rats, received 12 weeks of porcine serum injection to induce severe fibrosis. Treatment with ipragliflozin markedly attenuated the development of liver fibrosis and expression of hepatic fibrosis markers, such as alpha smooth muscle actin, collagen 1A1, and transforming growth factor beta (TGF-ß), and improved IR in a dose-dependent manner in OLETF rats. In contrast, the proliferation of LX-2 in vitro was not affected, suggesting that ipragliflozin had no significant direct effect on the proliferation of HSCs. CONCLUSION: In conclusion, our dataset suggests that an SGLT2 inhibitor could alleviate the development of liver fibrosis by improving IR in naturally diabetic rats. This may provide the basis for creating new therapeutic strategies for chronic liver injuries with IR.

Beneficial effects of combined ursodeoxycholic acid and angiotensin-II type 1 receptor blocker on hepatic fibrogenesis in a rat model of nonalcoholic steatohepatitis.

BACKGROUND AND AIMS: Ursodeoxycholic acid (UDCA) is considered to be effective in the treatment of nonalcoholic steatohepatitis (NASH), particularly in combination with other pharmacological agents. UDCA reportedly counteracts the effects of endotoxemia. Previously, we demonstrated attenuated hepatic fibrogenesis and suppression of activated hepatic stellate cells (Ac-HSC) with an angiotensin-II (AT-II) type 1 receptor blocker (ARB). Here we evaluated the simultaneous effect of both agents on hepatic fibrogenesis in a rat model of NASH. METHODS: Fischer 344 rats were fed a choline-deficient L-amino-acid-defined (CDAA) diet for 8 weeks. The therapeutic effect of UDCA and ARB was evaluated along with hepatic fibrogenesis, lipopolysaccharide (LPS)-Toll-like receptor 4 (TLR4) regulatory cascade, and intestinal barrier function. The direct inhibitory effect of both UDCA and ARB on Ac-HSC was assessed in vitro. RESULTS: Both UDCA and ARB had a potent inhibitory effect on hepatic fibrogenesis with suppression of the HSC activation and hepatic expression of transforming growth factor (TGF)-ß1 and TLR4. UDCA decreased intestinal permeability by ameliorating zonula occuludens-1 (ZO-1) disruption induced by the CDAA diet. ARB was found to directly suppress regulation of Ac-HSC. CONCLUSIONS: UDCA and ARB have a synergistic repressive effect on hepatic fibrogenesis by counteracting endotoxemia induced by intestinal barrier dysfunction and suppressing the activation of Ac-HSC. Because both agents are currently used in clinical practice, combined UDCA and ARB may represent a promising novel therapeutic approach for NASH.

DNA methylation of angiotensin II receptor gene in nonalcoholic steatohepatitis-related liver fibrosis.

AIM: To clarify whether Agtr1a methylation is involved in the development of nonalcoholic steatohepatitis (NASH)-related liver fibrosis in adult rats. METHODS: A choline-deficient amino acid (CDAA) diet model was employed for methylation analysis of NASH-related liver fibrosis. Agtr1a methylation levels were measured in the livers of CDAA- and control choline-sufficient amino acid (CSAA)-fed rats for 8 and 12 wk using quantitative methylation-specific PCR. Hepatic stellate cells (HSCs) were isolated by collagenase digestion of the liver, followed by centrifugation of the crude cell suspension through a density gradient. Agtr1a methylation and its gene expression were also analyzed during the activation of HSCs. RESULTS: The mean levels of Agtr1a methylation in the livers of CDAA-fed rats (11.5% and 18.6% at 8 and 12 wk, respectively) tended to be higher (P = 0.06 and 0.09, respectively) than those in the livers of CSAA-fed rats (2.1% and 5.3% at 8 and 12 wk, respectively). Agtr1a was not methylated at all in quiescent HSCs, but was clearly methylated in activated HSCs (13.8%, P < 0.01). Interestingly, although Agtr1a was hypermethylated, the Agtr1a mRNA level increased up to 2.2-fold (P < 0.05) in activated HSCs compared with that in quiescent HSCs, suggesting that Agtr1a methylation did not silence its expression but instead had the potential to upregulate its expression. These findings indicate that Agtr1a methylation and its upregulation of gene expression are associated with the development of NASH-related liver fibrosis. CONCLUSION: This is the first study to show that DNA methylation is potentially involved in the regulation of a renin-angiotensin system-related gene expression during liver fibrosis.