GLP-1改善非酒精性脂肪肝病作用机制的研究进展

非酒精性脂肪肝病与肥胖、胰岛素抵抗、2型糖尿病和血脂紊乱等密切相关。随着肥胖和糖尿病的发病率逐渐增加,非酒精性脂肪肝病已成为全球最常见的慢性肝脏疾病。目前,NAFLD的治疗主要是改善生活方式、减轻体重和降脂药物的应用,尚缺乏特效的药物治疗。GLP-1主要用于糖尿病和减重治疗,但最近大量临床和临床前研究表明GLP-1可通过多种 机制减轻NAFLD。本文将GLP-1改善NAFLD的相关机制综述如下,进一步加深我们对GLP-1改善NAFLD分子机制的理解。     

A novel radiomics signature based on T2-weighted imaging accurately predicts hepatic inflammation in individuals with biopsy-proven nonalcoholic fatty liver disease: a derivation and independent validation study

BackgroundCurrently, there are no effective methods for assessing hepatic inflammation without resorting to histological examination of liver tissue obtained by biopsy. T2-weighted images (T2WI) are routinely obtained from liver magnetic resonance imaging (MRI) scan sequences. We aimed to establish a radiomics signature based on T2WI (T2-RS) for assessment of hepatic inflammation in people with nonalcoholic fatty liver disease (NAFLD).MethodsA total of 203 individuals with biopsy-confirmed NAFLD from two independent Chinese cohorts with liver MRI examination were enrolled in this study. The hepatic inflammatory activity score (IAS) was calculated by the unweighted sum of the histologic scores for lobular inflammation and ballooning. One thousand and thirty-two radiomics features were extracted from the localized region of interest (ROI) in the right liver lobe of T2WI and, subsequently, selected by minimum redundancy maximum relevance and least absolute shrinkage and selection operator (LASSO) methods. The T2-RS was calculated by adding the selected features weighted by their coefficients.ResultsEighteen radiomics features from Laplacian of Gaussian, wavelet, and original images were selected for establishing T2-RS. The T2-RS value differed significantly between groups with increasing grades of hepatic inflammation (P<0.01). The T2-RS yielded an area under the receiver operating characteristic (ROC) curve (AUROC) of 0.80 [95% confidence interval (CI): 0.71–0.89] for predicting hepatic inflammation in the training cohort with excellent calibration. The AUROCs of T2-RS in the internal cohort and external validation cohorts were 0.77 (0.61–0.93) and 0.75 (0.63–0.84), respectively.ConclusionsThe T2-RS derived from radiomics analysis of T2WI shows promising utility for predicting hepatic inflammation in individuals with NAFLD.     

Serum markers detect the presence of liver fibrosis: a cohort study

BACKGROUND & AIMS: Histologic examination of a liver biopsy specimen is regarded as the reference standard for detecting liver fibrosis. Biopsy can be painful and hazardous, and assessment is subjective and prone to sampling error. We developed a panel of sensitive automated immunoassays to detect matrix constituents and mediators of matrix remodeling in serum to evaluate their performance in the detection of liver fibrosis. METHODS: In an international multicenter cohort study, serum levels of 9 surrogate markers of liver fibrosis were compared with fibrosis stage in liver biopsy specimens obtained from 1021 subjects with chronic liver disease. Discriminant analysis of a test set of samples was used to identify an algorithm combining age, hyaluronic acid, amino-terminal propeptide of type III collagen, and tissue inhibitor of matrix metalloproteinase 1 that was subsequently evaluated using a validation set of biopsy specimens and serum samples. RESULTS: The algorithm detected fibrosis (sensitivity, 90%) and accurately detected the absence of fibrosis (negative predictive value for significant fibrosis, 92%; area under the curve of a receiver operating characteristic plot, .804; standard error, .02; P < .0001; 95% confidence interval, .758-.851). Performance was excellent for alcoholic liver disease and nonalcoholic fatty liver disease. The algorithm performed equally well in comparison with each of the pathologists. In contrast, pathologists' agreement over histologic scores ranged from very good to moderate (kappa = .97-.46). CONCLUSIONS: Assessment of liver fibrosis with multiple serum markers used in combination is sensitive, specific, and reproducible, suggesting they may be used in conjunction with liver biopsy to assess a range of chronic liver diseases.     

Association of LDLR rs1433099 with the Risk of NAFLD and CVD in Chinese Han Population

Background and AimsRecent genome-wide association studies have shown that low-density lipoprotein receptor (LDLR) rs1433099 polymorphism is associated with cardiovascular disease (CVD) risk in many countries. However, the association of LDLR rs1433099 with CVD in China has not been reported yet. There are no studies on LDLR rs1433099 and non-alcoholic fatty liver disease (NAFLD) as well. The purpose of this study was to investigate whether LDLR rs1433099 is related to CVD or NAFLD in the Chinese population.MethodsLDLR rs1433099 polymorphism was genotyped in 507 individuals, including 140 healthy controls, 79 NAFLD patients, 185 CVD patients, and 103 patients with NAFLD combined with CVD. The expression of LDLR was tested by the sequence detection system, and clinical parameters were assessed by biochemical tests and physical examination.ResultsThe genotype distribution of LDLR rs1433099 was not statistically different among the NAFLD group, the CVD group, the combined group, and the healthy control group (p>0.05). There was no significant correlation of LDLR rs1433099 genotypic distribution or allele frequency and the risk of NAFLD, CVD or NAFLD combined with CVD (p>0.05). In the CVD group, T allele carriers had higher alkaline phosphatase and gamma-glutamyl transpeptidase than non-carriers (p<0.05).ConclusionsOur study demonstrated that the LDLR rs1433099 polymorphism is not a risk factor of NAFLD. The LDLR rs1433099 polymorphism may increase the risk of CVD through a mechanism involving alkaline phosphatase and gamma-glutamyl transpeptidase.     

脂联素与非酒精性脂肪肝肝纤维化及胰岛素抵抗的关系

目的：研究脂联素水平与非酒精性脂肪肝（NAFLD）患者肝纤维化指标及胰岛素抵抗指数（IRI）的关系。方法：采用ELISA法检测NAFLD患者和正常对照组的脂联素水平及Ⅲ型前胶原（PCⅢ）、透明质酸（HA）、Ⅳ型胶原（CⅣ）、层黏蛋白（LN）水平,采用稳态模式胰岛素抵抗指数（HOMA IRI）评估胰岛素抵抗。结果：NAFLD组脂联素水平显著低于对照组,胰岛素抵抗指数与肝纤维化指标显著高于对照组（P〈0.05）,IRI与PCⅢ、PCⅣ、HA和LN呈显著正相关（P〈0.05）,脂联素水平与WHR、BMI、FBG、Tg、FINS、HOMA-IRI、PCⅢ、PCⅣ、HA和LN呈显著负相关（P〈0.01或〈0.05）。结论：NAFLD患者血清脂联素水平降低,脂联素的表达在NAFLD患者肝纤维化与胰岛素抵抗进程中可能起重要作用。     

Novel non‐alcoholic steatohepatitis model with histopathological and insulin‐resistant features

Although several non‐alcoholic steatohepatitis (NASH) models have been reported to date, few of these models fully reflect the histopathology and pathophysiology of human NASH. The aim of this study was to establish a novel NASH model by feeding a high‐fat (HF) diet and administering both carbon tetrachloride (CCl₄) and the Liver X receptor agonist T0901317. Male C57BL/6J mice were divided into four groups (each n = 5): HF, HF + CCl₄, HF + T0901317, and the novel NASH model (HF + CCl₄ + T0901317). CCl₄ (0.1 mL/kg) and T0901317 (2.5 mg/kg) were intraperitoneally administered four times and five times, respectively. The livers of the novel NASH model group presented a whitish colour. The serum levels of TNF‐α and IL‐6 were significantly increased in the novel NASH model group, and mice in this group exhibited histopathological features and insulin resistance reflective of NASH, i.e., macrovesicular hepatic steatosis, ballooning hepatocytes, Mallory‐Denk bodies, lobular inflammation and fibrosis. The novel NASH model group presented significantly upregulated expression levels of mRNAs related to lipogenesis, oxidative stress, fibrosis and steatosis and significantly downregulated expression levels of mRNAs related to triglyceride export. We successfully established a novel experimental NASH model that exhibits similar histopathology and pathophysiology to human NASH.