Tomoyuki Iwasaki

High-sensitivity C-reactive protein is an independent clinical feature of nonalcoholic steatohepatitis (NASH) and also of the severity of fibrosis in NASH

BackgroundThe changes in nonalcoholic fatty liver disease (NAFLD) range over a wide spectrum, extending from steatosis to steatohepatitis (NASH). However, it has remained difficult to differentiate between NASH and nonprogressive NAFLD by clinical examination. We investigated the interrelationships between serum high-sensitivity C-reactive protein (hs-CRP) and the pathogenesis and progression of NASH.MethodsHs-CRP was measured in 100 patients with histologically verified NAFLD (29 with steatosis and 71 with NASH), and a real-time reverse transcriptase-polymerase chain reaction (RT-PCR) analysis was performed to measure the intrahepatic mRNA expressions of CRP and interleukin (IL)-6.ResultsThe results of a multiple regression analysis revealed that in comparison with cases of steatosis, hs-CRP was significantly elevated (P = 0.0048) in cases of NASH. Furthermore, among patients with NASH, hs-CRP was significantly elevated in those with advanced fibrosis compared with that in those with mild fibrosis (P = 0.0384), even after adjustment for age, sex, presence of diabetes, body mass index, visceral fat area, subcutaneous fat area, homeostasis model assessment for insulin resistance, high-density lipoprotein cholesterol, triglyceride, and low-density lipoprotein cholesterol. The results of the RT-PCR analysis showed that intrahepatic mRNA expression of CRP, but not IL-6, was increased in patients with NASH compared with those with steatosis (P = 0.0228).ConclusionsThis is the first report to demonstrate consistent and profound elevation of hs-CRP in cases of NASH compared with in cases of simple nonprogressive steatosis. Our results suggest that hs-CRP may be a clinical feature that not only distinguishes NASH from simple nonprogressive steatosis but also indicates the severity of hepatic fibrosis in cases of NASH.

Efficacy of ezetimibe for the treatment of non-alcoholic steatohepatitis : An open-label, pilot study

Aim:  Non‐alcoholic steatohepatitis (NASH) is considered a hepatic manifestation of metabolic syndrome. However, effective drug therapy for NASH has not been established yet. In the present study, we evaluated the efficacy of 6 months of ezetimibe treatment for NASH patients with dyslipidemia for the comparison of improvement of the clinical parameters and histological alterations.

Sitagliptin as a novel treatment agent for non-alcoholic Fatty liver disease patients with type 2 diabetes mellitus.

BACKGROUND/AIMS Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver injury, and is considered as the hepatic manifestation of metabolic syndrome. However, no effective drug therapy for NAFLD has been established yet. In the present study, we evaluated the efficacy of 4 months of treatment with sitagliptin in NAFLD patients with type 2 diabetes mellitus (DM). METHODOLOGY We evaluated 30 NAFLD patients with type 2 DM. NAFLD was diagnosed by ultrasonography. The patients were administered sitagliptin (50mg/body/day) for 4 months. RESULTS significant decreases of the plasma glucose and serum HbA1c, AST, ALT and γ-GTP levels were observed after 4 months of treatment with sitagliptin. CONCLUSIONS In this study, not only the parameters of diabetes, but also those of liver tests were improved by the treatment with sitagliptin. Our study demonstrated the efficacy of sitagliptin in NAFLD patients with type 2 DM, suggesting that a large-scale clinical trial is warranted in the future.

Hepatitis C virus directly associates with insulin resistance independent of the visceral fat area in nonobese and nondiabetic patients

Summary.  Insulin resistance (IR) is known to be associated with the visceral adipose tissue area. Elucidation of the relationship between hepatitis C virus (HCV) and IR is of great clinical relevance, because IR promotes liver fibrosis. In this study, we tested the hypothesis that HCV infection by itself may promote IR. We prospectively evaluated 47 patients with chronic HCV infection who underwent liver biopsy. Patients with obesity, type 2 diabetes mellitus (DM), or a history of alcohol consumption were excluded. IR was estimated by calculation of the modified homeostasis model of insulin resistance (HOMA‐IR) index. Abdominal fat distribution was determined by computed tomography. Fasting blood glucose levels were within normal range in all the patients. The results of univariate analysis revealed a significant correlation between the quantity of HCV‐RNA and the HOMA‐IR (r = 0.368, P = 0.0291). While a significant correlation between the visceral adipose tissue area and the HOMA‐IR was also observed in the 97 control, nondiabetic, non‐HCV‐infected patients (r = 0.398, P < 0.0001), no such significant correlation between the visceral adipose tissue area and the HOMA‐IR (r = 0.124, P = 0.496) was observed in the patients with HCV infection. Multiple regression analysis with adjustment for age, gender and visceral adipose tissue area revealed a significant correlation between the HCV‐RNA and the HOMA‐IR (P = 0.0446). HCV is directly associated with IR in a dose‐dependent manner, independent of the visceral adipose tissue area. This is the first report to demonstrate the direct involvement of HCV and IR in patients with chronic HCV infection.

Type IV collagen 7s domain is an independent clinical marker of the severity of fibrosis in patients with nonalcoholic steatohepatitis before the cirrhotic stage

BackgroundThe changes in nonalcoholic fatty liver disease range over a wide spectrum, extending from simple steatosis to nonalcoholic steatohepatitis (NASH). We investigated the clinical usefulness of the type IV collagen 7s domain and hyaluronic acid for predicting the severity of fibrosis before progression to the cirrhotic stage in NASH patients.MethodsThe type IV collagen 7s domain and hyaluronic acid were measured in 72 patients with histologically verified NASH.ResultsIn a univariate analysis, marked elevation of hyaluronic acid and the type IV collagen 7s domain was observed in the NASH patients with advanced fibrosis compared with those with mild fibrosis (P = 0.0028, P = 0.0006, respectively). For detection of NASH with advanced fibrosis, the area under the receiver-operating characteristic curves for type IV collagen 7s domain and hyaluronic acid were 0.767 and 0.754, respectively. However, multiple regression analysis revealed that the type IV collagen 7s domain, but not hyaluronic acid, was significantly elevated in patients with advanced fibrosis even after adjustment for age, sex, platelet count, prothrombin time, aspartate aminotransferase/alanine aminotransferase ratio, body mass index, and presence of underlying type 2 diabetes mellitus, all of which have previously been reported as useful predictors of advanced fibrosis in patients with NASH (P = 0.0127, P = 0.2804, respectively).ConclusionsThis is the first report to demonstrate a consistent and profound elevation of the type IV collagen 7s domain in NASH patients with advanced fibrosis (before progression to the stage of cirrhosis) compared with those with mild fibrosis.

Effectiveness of antiplatelet drugs against experimental non-alcoholic fatty liver disease

Objective: No effective drugs have been developed to date to prevent or treat non-alcoholic fatty liver disease (NAFLD), although diet modification and exercise to improve obesity have been attempted. Therefore, development of a novel drug/strategy to treat NAFLD is urgently needed. In the present study, a novel concept is proposed for the treatment of NAFLD. Methods: Fisher 344 male rats were given a choline-deficient, l-amino acid-defined (CDAA) diet or a high-fat high-calorie (HF/HC) diet with or without the antiplatelet agents, aspirin, ticlopidine or cilostazol for 16 weeks. Liver steatosis, inflammation and fibrosis, and the possible mechanisms involved were investigated. Results: All three antiplatelet drugs, namely aspirin, ticlopidine and cilostazol, significantly attenuated liver steatosis, inflammation and fibrosis in the CDAA diet group. Of the three agents, cilostazol was the most effective, and the drug also suppressed HF/HC diet-induced liver steatosis. Cilostazol appeared to exert its beneficial effect against NAFLD by suppressing mitogen-activated protein kinase activation induced by oxidative stress and platelet-derived growth factor via intercepting signal transduction from Akt to c-Raf. Conclusion: Antiplatelet agents, especially cilostazol, offer the promise of becoming key agents for the treatment of NAFLD.

Telmisartan, An Angiotensin II Type 1 Receptor Blocker, Controls Progress of Nonalcoholic Steatohepatitis in Rats

The term nonalcoholic steatohepatitis (NASH) has recently been proposed to identify a fatty liver disease accompanied by diffuse fatty infiltration and inflammation. However, no drug therapy has been established for NASH as yet. In the present study, we demonstrate the effect of the angiotensin II type 1 receptor antagonist telmisartan on the development of NASH in a rat model. Telmisartan, but not the angiotensin receptor antagonist valsartan, markedly attenuated hepatic steatosis, inflammation, and fibrosis in these rats. The quantitative parameters of steatosis, inflammation, and fibrosis were also ameliorated by treatment with telmisartan. Compared with telmisartan, the peroxisome proliferator-activated receptor-γ agonist pioglitazone attenuated hepatic steatosis and fibrosis of the liver to a similar degree. However, telmisartan, but not pioglitazone, dramatically decreased both subcutaneous and visceral fat. In conclusion, these results indicated that telmisartan should be the drug of first choice for the treatment of patients with NASH.

Nitric oxide plays a crucial role in the development/progression of nonalcoholic steatohepatitis in the choline-deficient, l-amino acid-defined diet-fed rat model.

BACKGROUND The pathogenesis of nonalcoholic steatohepatitis (NASH) is still unclear. Recently, the 2-hit hypothesis was proposed, in which nitric oxide production, representing oxidative stress, was proposed as a very important candidate for the second hit. METHODS The total study period was 10 weeks. A total of 20 rats were randomly divided into 2 groups. Group 1 was administered the Choline-Deficient, l-Amino Acid-Defined diet to produce a NASH model, and Group 2 as control received the Choline-Sufficient, l-Amino Acid-defined diet. The blood and tissue concentrations of nitrate + nitrite were measured using the Griess reagent and the expression levels of inducible nitric oxide synthase (iNOS) proteins and mRNA was determined by Western blotting. RESULTS In regard to nitric oxide (NO) and NO metabolites, there were significant differences in the blood (especially portal venous blood) as well as tissue (liver and visceral fat) concentrations between the 2 animal groups; the amounts of NO metabolites in the tissues were much higher in the NASH models. The level of nitrotyrosine was much markedly higher in the NASH models than in the controls. In regard to the tissue expression of iNOS a significant difference between the 2 groups was found in the visceral fat, especially in the mesenterium. CONCLUSIONS Based on these results, we hypothesize that the iNOS expression and NO levels in the visceral fat increase, with increased diffusion of NO and its metabolites into the liver, resulting in increased nitrotyrosine formation in the liver; this, in turn, induces inflammation, apoptosis, and fibrosis in the liver, which are one of the characteristic features of NASH.

Ezetimibe decreases SREBP-1c expression in liver and reverses hepatic insulin resistance in mice fed a high-fat diet

Ezetimibe inhibits intestinal cholesterol absorption, thereby reducing serum cholesterol. Recent studies suggest that ezetimibe affects liver steatosis and insulin resistance. We investigated the impact of ezetimibe on insulin sensitivity and glucose metabolism in C57BL/6 mice. We analyzed 4 mouse groups fed the following diets: normal chow (4% fat) for 12 weeks, normal chow for 10 weeks followed by normal chow plus ezetimibe for 2 weeks, high-fat chow (32% fat) for 12 weeks, and high-fat chow for 10 weeks followed by high-fat chow plus ezetimibe for 2 weeks. In the normal chow + ezetimibe group, ezetimibe had no impact on body weight, fat mass, lipid metabolism, liver steatosis, glucose tolerance, or insulin sensitivity. In the high-fat chow + ezetimibe group, ezetimibe had no impact on body weight or fat mass but significantly decreased serum low-density lipoprotein cholesterol, triglyceride, and glutamate pyruvate transaminase levels; liver weight; hepatic triglyceride content; and hepatic cholesterol content and increased the hepatic total bile acid content. In association with increases in IRS-2 and Akt phosphorylation, ezetimibe ameliorated hepatic insulin resistance in the high-fat chow + ezetimibe group, but had no effect on insulin sensitivity in primary cultured hepatocytes. A DNA microarray and Taqman polymerase chain reaction revealed that ezetimibe up-regulated hepatic SREBP2 and SHP expression and down-regulated hepatic SREBP-1c expression. SHP silencing mainly in the liver worsened insulin resistance, and ezetimibe protected against insulin resistance induced by down-regulation of SHP. Ezetimibe down-regulated SREBP-1c in the liver and reversed hepatic insulin resistance in mice fed a high-fat diet.

Early effects of lafutidine or rabeprazole on intragastric acidity: which drug is more suitable for on-demand use?

BackgroundMedication for the relief of heartburn should have the rapid onset of action required for on-demand use. We studied the inhibition of gastric acid secretion by lafutidine and rabeprazole, given in single doses to fasting and postprandial subjects.MethodsA total of 22 healthy male, Helicobacter pylori-negative volunteers participated in this randomized, two-way crossover study. They were randomly assigned to receive a single oral dose of 10 mg lafutidine or 20 mg rabeprazole after fasting overnight (12 subjects, fasting study) or after eating a test meal (noodles, 364 kcal; protein, 10.1 g; fat, 16 g; carbohydrates, 44.9 g; NaCl, 1.1 g; 10 subjects, postprandial study). Intragastric pH was monitored continuously for 6 h after treatment. The other drug was given after a washout period of at least 7 days, and intragastric pH was similarly monitored.ResultsIn the fasting study, lafutidine sustained pH at >3 and >4 during the second, third, fourth, fifth, and sixth hours of the study for significantly longer than rabeprazole. During the first 6 h after treatment, lafutidine sustained pH at more than 2, 3, 3.5, 4, 5, 6, and 7 longer than rabeprazole. In the postprandial study, lafutidine sustained pH >3 and >4 for longer periods than rabeprazole during the third, fourth, fifth, and sixth hours of the study. During the first 6 h after treatment, lafutidine sustained pH at more than 2, 3, 3.5, 4, 5, 6, and 7 longer than rabeprazole.ConclusionsLafutidine 10 mg produces a prompter rise in intragastric pH than rabeprazole 20 mg in fasting and postprandial Helicobacter pylori-negative male subjects.