Does steatohepatitis impair liver regeneration? A study in a dietary model of non-alcoholic steatohepatitis in rats

BACKGROUND: Impaired liver regeneration is a feature of alcoholic hepatitis, but the relative importance of alcohol, nutritional imbalance and inflammatory mediators in causing this effect is unclear. Non-alcoholic steatohepatitis (NASH) is a form of liver disease with similar morphology to alcoholic hepatitis, but the effect of this disorder on liver regeneration is unclear. We, therefore, examined the status of liver regeneration in a rat nutritional model of hepatic steatosis with inflammation, which is morphologically identical to NASH in humans. Methods: Male Wistar rats received a methionine-choline-deficient diet (MCDD) for 4 weeks before experiments and both isocaloric pair-fed and ad libitum-fed rats were used as controls. Following partial hepatectomy (68%), the extent of hepatic regeneration was determined 24 h later using [3H]-thymidine incorporation and restitution of liver mass. Results: There was no significant difference of [3H]-thymidine incorporation in MCDD-fed, pair-fed and ad libitum-fed rats (80+/-27, 78+/-11 and 80+/-6.3 d.p.m./microg DNA, respectively). Similarly, restituted liver masses in three groups of rats were not significantly different (17+/-3.8, 18+/-1.8 and 17+/-3.1% initial liver weight, respectively). Conclusions: The similarities in hepatic histology and cytochrome P450 2E1 induction between this nutritional model of hepatic steatohepatitis and alcoholic steatohepatitis imply that these two disorders share pathogenetic mechanisms. However, liver regeneration is not altered by NASH in rats, indicating that the nutritional and inflammatory changes that appear similar to those of alcoholic liver disease do not cause impairment of liver regeneration.     

Insulin resistance and C-reactive protein as independent risk factors for non-alcoholic fatty liver disease in non-obese Asian men

BACKGROUND AND AIM: Although insulin resistance is often considered the link between obesity and non-alcoholic fatty liver disease (NAFLD), the role of insulin resistance, independent of obesity, as a NAFLD risk factor in non-obese men has been less well established. Systemic inflammation may be accompanied by insulin resistance in healthy subjects. The goal of the present study was to examine if insulin resistance and systemic inflammatory markers are independent predictors of NAFLD in non-obese men. METHODS: The authors conducted a cross-sectional survey of 120 patients with NAFLD and 240 controls matched by age and body mass index. Controls had no evidence of alcohol abuse, hepatitis B or C, obesity, or previous history of diabetes, fasting hyperglycemia or hypertension. Diagnosis of NAFLD was based on an elevated alanine aminotransferase level and sonographic evidence of a fatty liver. Insulin resistance was determined using a homeostasis model assessment (HOMA-IR). RESULTS: The age-adjusted risk of developing NAFLD was strongly associated with the elevated levels in measurements of uric acid, fasting blood sugar, triglycerides, apolipoprotein B, C-reactive protein (CRP) and HOMA-IR, and decreased levels of high density lipoprotein cholesterol and apolipoprotein A-I. Multivariate analysis based on univariate analysis indicated that an increase in CRP (odds ratio [OR] = 1.37; 95% confidence interval [CI]: 1.06-1.77) per 1 SD (1.48 mg/L) and HOMA-IR (OR = 2.28; 95% CI: 1.67-3.11) per 1 SD (0.63) were independent risk factors for NAFLD. CONCLUSION: Insulin resistance and systemic inflammatory response are of key importance for inducing NAFLD, particularly in apparently healthy non-obese men.     

Fasting insulin and uric acid levels but not indices of iron metabolism are independent predictors of non-alcoholic fatty liver disease. A case-control study

BACKGROUND: Non-alcoholic fatty liver disease is a common reason for hepatological consultation and may herald severe hepatic and extra-hepatic disease. The aetiopathogenesis of this condition is an area of increasing interest. AIM: To evaluate anthropometric and biochemical factors associated to non-alcoholic fatty liver disease in a case-control study. Methods. Demographic and biochemical data of 60 consecutive patients with bright liver absent-to-low alcohol consumption, no evidence of viral, genetic and autoimmune diseases, were compared to those of 60 age- and gender-matched historical controls without fatty liver by univariate and multiple logistic regression analysis. RESULTS: Patients were more often hypertriglyceridaemic, obese and diabetic than controls (p<.01). Mean values of alanine transaminase, gammaglutamyltranspeptidase, triglycerides, uric acid, fasting and log insulin, transferrin percent saturation and ferritin were significantly higher in the patients, while transferrin and quantitative insulin sensitivity check index, a quantitative insulin sensitivity index, were lower. No iron storage was found in those who underwent liver biopsy At univariate analysis the relative risk for non-alcoholic fatty liver disease significantly increased (p<0. 05) with increasing body mass index, fasting insulin, alanine transaminase, uric acid, triglycerides and gammaglutamyltranspeptidase; it decreased with increasing transferrin and quantitative insulin sensitivity check index. Multiple logistic regression analysis disclosed only fasting insulin and uric acid to be independent predictors of non-alcoholic fatty liver disease (p<0.05). CONCLUSIONS: Fasting insulin and serum uric acid levels indicating insulin resistance, but not indices of iron overload, are independent predictors of non-alcoholic fatty liver disease.     

Ursodeoxycholic acid: Mechanism of action and novel clinical applications.

Ursodeoxycholic acid (UDCA) is used in the treatment of cholestatic liver diseases, gallstone dissolution, and for patients with hepatitis C virus infection to ameliorate elevated alanine aminotransferase levels. The efficacy of UDCA treatment has been debated and the mechanisms of action in humans have still not defined. Suggested mechanisms include the improvement of bile acid transport and/or detoxification, cytoprotection, and anti-apoptotic effects. In this review, we summarize the proposed molecular mechanisms for the action of UDCA, especially in hepatocytes, and also discuss the putative future clinical usage of this unique drug.     

老年非酒精性脂肪肝患者25(OH)D3水平与胰岛素抵抗、氧化应激的相关性

 目的 探究老年非酒精性脂肪肝(non-alcoholic fatty liver disease,NAFLD)患者血清25-羟维生素D₃[25(OH)D₃]水平的变化及与胰岛素抵抗、氧化应激之间的关系。方法 选取2018-01至2020-04在我院诊治的125例老年NAFLD患者作为观察组,按血清25(OH)D₃水平分为维生素D缺乏组、维生素D不足组和维生素D正常组三个亚组;另选取同期老年健康体检者30例作为对照组。比较观察组与对照组血清25(OH)D₃水平差异;对比观察组三个亚组体质量(BMI)、血脂、肝功能、空腹血糖(FBG)、空腹胰岛素(FINS)、胰岛素抵抗指数(HOMA-IR)、丙二醛(MDA)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)等各指标差异;分析观察组血清25(OH)D₃水平与以上指标的相关性。结果 与对照组相比,观察组25(OH)D₃、SOD、GSH-Px水平显著下降,BMI、FINS、HOMA-IR、MDA水平显著升高(P<0.05)。与维生素D正常组相比,维生素D缺乏组和维生素D不足组FINS、HOMA-IR、MDA水平显著升高,SOD、GSH-Px水平显著降低(P<0.05);其中维生素D缺乏组各指标水平高于或低于维生素D不足组(P<0.05)。观察组25(OH)D₃水平与HOMA-IR、MDA呈显著负相关(r=-0.395,r=-0.328,P均<0.05);与SOD、GSH-Px呈显著正相关(r=0.388,r=0.376,P均<0.05)。结论 老年NAFLD患者血清25(OH)D₃水平明显下降,血清25(OH)D3缺乏与胰岛素抵抗及氧化应激密切相关。     

Liver steatosis assessment: Correlations among pathology,radiology, clinical data and automated image analysis software

Quantitating hepatic steatosis is important in many liver diseases and liver transplantation. Since steatosis estimation by pathologists has inherent intra- and inter-observer variability, we compared and contrasted computerized techniques with magnetic resonance imaging measurements, pathologist visual scoring, and clinical parameters. Computerized methods applied to whole slide images included a commercial positive pixel count algorithm and a custom algorithm programmed at our institution. For all liver samples (n = 59), including pediatric, adult, frozen section, and permanent specimens, statistically significant correlations were observed between pathology, radiology, and each image analysis modality (r = 0.75–0.97, p < 0.0001), with the strongest correlations in the pediatric cohort. Statistically significant relationships were observed between each method and with body mass index (r = 0.37–0.56, p from <0.0001 to <0.05) and with albumin (r = 0.55–0.64, p < 0.05) but not with alanine aminotransferase or aspartate aminotransferase. Although pathologist assessments correlated (r = 0.64–0.86, 0.92–0.97, and 0.78–0.91 for microvesicular, macrovesicular, and overall steatosis, respectively), the absolute values of hepatic steatosis visual assessment were susceptible to intra- and inter-observer variability, particularly for microvesicular steatosis. Image analysis, pathologist assessments, radiology measurements, and several clinical parameters all showed correlations in this study, providing evidence for the utility of each method in different clinical and research settings.     

Longitudinal correlations between MRE,MRI-PDFF,and liver histology in patients with non-alcoholic steatohepatitis: Analysis of data from a phase II trial of selonsertib

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A PNPLA3 Polymorphism Confers Lower Susceptibility to Incident Diabetes Mellitus in Subjects With Nonalcoholic Fatty Liver Disease

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