Hideyuki Hyogo

Efficacy of atorvastatin for the treatment of nonalcoholic steatohepatitis with dyslipidemia

Nonalcoholic steatohepatitis (NASH) is the hepatic manifestation of the metabolic syndrome. Currently, there is no established therapy for NASH. The aim of the present study was to evaluate the efficacy of atorvastatin in the treatment of NASH associated with hyperlipidemia. This prospective study included 31 patients with biopsy-proven NASH with hyperlipidemia. Body mass index, serum lipids, liver function tests, fibrosis markers, and adipocytokines (adiponectin, leptin, tumor necrosis factor-alpha) were measured periodically during an open-label study of atorvastatin (10 mg daily) for 24 months. Standard weight-loss counseling was continued during the treatment period. Oral glucose tolerance test and liver density assessed by computerized tomography were performed before and after treatment. Follow-up liver biopsy was performed in 17 patients. All 31 patients had high cholesterol levels at baseline, and 20 also presented high triglyceride levels. The body mass index and serum glucose levels did not change during the treatment. After treatment, 23 patients (74.2%) presented normal transaminase levels. Adiponectin levels were significantly increased, and the levels of tumor necrosis factor-alpha were significantly decreased. However, leptin levels were not changed significantly. The concentration of long-chain fatty acids was decreased; and significant decreases were observed in C18:2,n-6 (linoleic acid, -21%) and C20:4,n-6 (arachidonic acid, -22%). Liver steatosis and nonalcoholic fatty liver disease activity score were significantly improved, whereas 4 patients had increased fibrosis stage. The NASH-related metabolic parameters improved with therapy, including fibrosis in some patients. However, 4 of 17 patients had progression of fibrosis over the 2-year period, with 3 of them progressing to stage 3. It is unclear whether this divergent response represents sampling error, heterogeneity in the population, or untreated postprandial hyperglyceridemia. Controlled trials are needed to further investigate and resolve this.

Elevated levels of serum advanced glycation end products in patients with non-alcoholic steatohepatitis

Background and Aim:  Advanced glycation end products (AGE), senescent macroprotein derivatives formed at an accelerated rate in diabetes, play important roles in the pathogenesis of diabetic vascular complications. Recently, AGE have also been found to be involved in insulin resistance. Although non‐alcoholic steatohepatitis (NASH) is generally considered a hepatic manifestation of insulin resistance, there are no reports showing the link of AGE to NASH. The aim of this study was to evaluate the clinical significance of AGE in patients with NASH.

Hepatitis C Virus Core Protein Modulates Fatty Acid Metabolism and Thereby Causes Lipid Accumulation in the Liver

We studied the roles of hepatitis C virus (HCV) core protein in hepatic steatosis and changes in hepatic lipid metabolism. HCV core protein expression plasmid was transfected in HepG2 . Triacylglyceride (TG) and mRNA level associated with lipid metabolism were measured. Male C57BL/6 mice were infected with HCV core recombinant adenovirus and used for lipids and mRNA studies. In HCV core protein-expressing cells, peroxisome proliferator-activated receptor (PPAR)α, multidrug resistance protein (MDR) 3, and microsomal triglyceride transfer protein (MTP) were down-regulated 48 hr after transfection. In HCV core protein-expressing mice, hepatic TG content and hepatic thiobarbituric acid-reactive substances increased. PPARα, MDR2, acyl-CoA oxidase (AOX), and carnitine palmitoyl transferase-1 (CPT-1) were down-regulated. HCV core protein down-regulated lipid metabolism-associated gene expression, Mdr2, CPT, and AOX, accompanied by down-regulation of PPARα. There findings may contribute to the understanding of HCV-related steatosis, induction of reactive oxygen species, and carcinogenesis.

Validation of the FIB4 index in a Japanese nonalcoholic fatty liver disease population

BackgroundA reliable and inexpensive noninvasive marker of hepatic fibrosis is required in patients with nonalcoholic fatty liver disease (NAFLD). FIB4 index (based on age, aspartate aminotransferase [AST] and alanine aminotransferase [ALT] levels, and platelet counts) is expected to be useful for evaluating hepatic fibrosis. We validated the performance of FIB4 index in a Japanese cohort with NAFLD.MethodsThe areas under the receiver operating characteristic curves (AUROC) for FIB4 and six other markers were compared, based on data from 576 biopsy-proven NAFLD patients. Advanced fibrosis was defined as stage 3-4 fibrosis. FIB4 index was assessed as: age (yr) × AST (IU/L)/(platelet count (109/L) × √ALT (IU/L))ResultsAdvanced fibrosis was found in 64 (11%) patients. The AUROC for FIB4 index was superior to those for the other scoring systems for differentiating between advanced and mild fibrosis. Only 6 of 308 patients with a FIB4 index below the proposed low cut-off point (< 1.45) were under-staged, giving a high negative predictive value of 98%. Twenty-eight of 59 patients with a FIB4 index above the high cut-off point (> 3.25) were over-staged, giving a low positive predictive value of 53%. Using these cutoffs, 91% of the 395 patients with FIB-4 values outside 1.45-3.25 would be correctly classified. Implementation of the FIB4 index in the Japanese population would avoid 58% of liver biopsies.ConclusionThe FIB4 index was superior to other tested noninvasive markers of fibrosis in Japanese patients with NAFLD, with a high negative predictive value for excluding advanced fibrosis. The small number of cases of advanced fibrosis in this cohort meant that this study had limited power for validating the high cut-off point.

Association of the rs738409 polymorphism in PNPLA3 with liver damage and the development of nonalcoholic fatty liver disease

BackgroundIn a genome-wide association scan, the single-nucleotide polymorphism (SNP) rs738409 in the patatin-like phospholipase 3 gene (PNPLA3) was strongly associated with increased liver fat content. We investigated whether this SNP is associated with the occurrence and progression of nonalcoholic fatty liver disease (NAFLD) in the Japanese population.MethodsSNP rs738409 was genotyped by the Taqman assay in 253 patients with NAFLD (189 with nonalcoholic steatohepatitis [NASH] and 64 with simple steatosis) and 578 control subjects. All patients with NAFLD underwent liver biopsy. Control subjects had no metabolic disorders. For a case-control study, the χ2-test (additive model) was performed. Odds ratios (ORs) were adjusted for age, gender, and body mass index (BMI) by using multiple logistic regression analysis with genotypes (additive model), age, gender, and BMI as the independent variables. Multiple linear regression analysis was performed to test the independent effect of risk allele on clinical parameters while considering the effects of other variables (age, gender, and BMI), which were assumed to be independent of the effect of the SNP.ResultsThe risk allele (G-allele) frequency of rs738409 was 0.44 in the control subjects and 0.60 in patients with NAFLD; this shows a strong association with NAFLD (additive model, P = 9.4 × 10-10). The OR (95% confidence interval) adjusted for age, gender, and BMI was 1.73 (1.25-2.38). Multiple linear regression analysis indicated that the G-allele of rs738409 was significantly associated with increases in aspartate transaminase (AST) (P = 0.00013), alanine transaminase (ALT) (P = 9.1 × 10-6), and ferritin levels (P = 0.014), and the fibrosis stage (P = 0.011) in the patients with NAFLD, even after adjustment for age, gender, and BMI. The steatosis grade was not associated with rs738409.ConclusionsWe found that in the Japanese population, individuals harboring the G-allele of rs738409 were susceptible to NAFLD, and that rs738409 was associated with plasma levels of ALT, AST, and ferritin, and the histological fibrosis stage. Our study suggests that PNPLA3 may be involved in the progression of fibrosis in NAFLD.

Advanced Glycation End Products (AGEs) and their Involvement in Liver Disease

Advanced glycation end products (AGEs) are a heterogeneous group of molecules, formed in vivo both by non-oxidative and oxidative reactions of sugars and their adducts to proteins and lipids. It is now well established that formation and accumulation of AGEs progress during normal aging, and at an extremely accelerated rate under diabetes, thus being implicated in various types of AGEs-related disorders such as diabetic vascular complications, neurodegenerative diseases and cancers. There is a growing body of evidence that activation of RAGE (receptor for AGEs) system is also implicated in these devastating disorders. Indeed, the engagement of RAGE with AGEs is shown to elicit oxidative stress generation and subsequently evoke inflammatory responses in various types of cells including hepatocytes and hepatic stellate cells. Liver is not only a target organ, but also an important site for clearance and catabolism of circulating AGEs. Although there are several papers to suggest the involvement of AGEs-RAGE system in various types of liver diseases such as non-alcoholic steatohepatitis, liver cirrhosis and cancers, as far as we know, there are few comprehensive reviews to deal with this issue. Therefore, in this paper, we shortly review the pathological role of AGEs and RAGE in various liver diseases.

Advanced glycation end products enhance the proliferation and activation of hepatic stellate cells.

BackgroundAdvanced glycation end products (AGEs), final reaction products of protein with sugars, are known to contribute to diabetes-related complications. We have recently demonstrated high levels of serum AGEs in patients with nonalcoholic steatohepatitis (NASH). However, direct evidence for the participation of AGEs in hepatic infl ammation and fibrosis has not been shown. To explore the pathogenesis of NASH, we examined the biological infl uence of AGEs on hepatic stellate cells (HSCs) in vitro.MethodsAn established human HSC line, LI90, was exposed to a glyceraldehyde-derived-AGE (glycer-AGE), and the phenotypical changes of the LI90 cells were investigated. Intracellular formation of reactive oxygen species (ROS) was measured using a fl uorescent probe. Cell proliferation was examined by MTS assay. Fibrogenic marker gene expression was analyzed by quantitative real-time polymerase chain reaction. The production of monocyte chemoattractant protein 1 (MCP-1) was assessed by enzyme-linked immunosorbent assay.ResultsThe expression of AGE receptor was confirmed in LI90 cells at the mRNA and protein levels. In addition to increasing intracellular ROS generation, glycer-AGE upregulated fibrogenic genes such as those encoding for α-smooth muscle actin, transforming growth factor-β1, and collagen type Iα2. The expression of MCP-1 mRNA in LI90 cells as well as its secretion into the culture medium was significantly increased in response to AGEs. These changes were attenuated by treatment with the antioxidant N-acetylcysteine.ConclusionsThese data indicate that AGEs induce ROS generation and intensify the proliferation and activation of HSCs, supporting the possibility that antioxidants may represent a promising treatment for prevention of the development of hepatic fibrosis in NASH.

Recent trend of clinical features in patients with hepatocellular carcinoma

Aim:  In this study, we evaluated the clinical characteristics of hepatocellular carcinoma (HCC) because the etiology of HCC has been changing recently.

Efficacy of pitavastatin for the treatment of non-alcoholic steatohepatitis with dyslipidemia: An open-label, pilot study.

Oxidative stress plays a pivotal role in the transition from simple steatosis to non‐alcoholic steatohepatitis (NASH). Probucol is a lipid‐lowering agent with strong antioxidant properties, and is reported to be effective for the treatment of NASH in several studies. The aim of the present study was to evaluate the efficacy of probucol for the treatment of NASH with dyslipidemia.

Angiotensin II Participates in Hepatic Inflammation and Fibrosis through MCP-1 Expression

In this study, we assessed the hypothesis that angiotensin (Ang) II could modulate inflammatory cell recruitment into the liver through hepatic expression of monocyte chemoattractant protein (MCP)-1 during liver injury. For in vivo study, Ang II type 1a knockout (AT1a KO) mice and wild-type (WT) mice were treated with CCl4 for 4 weeks. After CCl4 treatment, AT1a KO mice showed lower expression of MCP-1 and fewer CD68-positive cells in the liver compared with WT mice. For in vitro study, Ang II was added to LI90 cells. Ang II enhanced MCP-1 mRNA together with RhoA mRNA and also induced secretion of MCP-1 into the culture medium. This change was strongly blocked by Y-27632, a specific Rho-kinase inhibitor. These results suggest that Ang II modulates hepatic inflammation via production of MCP-1 by hepatic stellate cells, and the effect of Ang II on MCP-1 production is, at least partly, mediated by the Rho/Rho-kinase pathway.