No abstract

Background: As one of the most common liver disorders worldwide, non-alcoholic fatty liver disease (NAFLD) begins with the abnormal accumulation of triglyceride (TG) in the liver. Long non-coding RNA-H19 was reported to modulate hepatic metabolic homeostasis in NAFLD. However, its molecular mechanism of NAFLD was not fully clear. Methods: In vitro and in vivo models of NAFLD were established by free fatty acid (FFA) treatment of hepatocytes and high-fat feeding mice, respectively. Hematoxylin and Eosin (H&E) and Oil-Red O staining detected liver tissue morphology and lipid accumulation. Immunohistochemistry (IHC) staining examined peroxisome proliferator-activated receptor γ (PPARγ) level in liver tissues. ELISA assay assessed TG secretion. Luciferase assay and RNA pull down were used to validate regulatory mechanism among H19, miR-130a and PPARγ. The gene expression in hepatocytes and liver tissues was detected by quantitative real-time PCR (qRT-PCR) and Western blotting. Results: H19 and PPARγ were up-regulated, while miR-130a was down-regulated in NAFLD mouse and cellular model. H&E and Oil-Red O staining indicated an increased lipid accumulation. Knockdown of H19 inhibited steatosis and TG secretion in FFA-induced hepatocytes. H19 could bind to miR-130a, and miR-130a could directly inhibit PPARγ expression. Meanwhile, miR-130a inhibited lipid accumulation by down-regulating NAFLD-related genes PPARγ, SREBP1, SCD1, ACC1 and FASN. Overexpression of miR-130a and PPARγ antagonist GW9662 inhibited lipogenesis and TG secretion, and PPARγ agonist GW1929 reversed this change induced by miR-130a up-regulation. Conclusion: Knockdown of H19 alleviated hepatic lipogenesis via directly regulating miR-130a/PPARγ axis, which is a novel mechanistic role of H19 in the regulation of NAFLD.

The aim of the study was to determine the pharmacokinetics of losartan in relation to the CYP2C9*13 allele. A single oral dose of 50 mg losartan was administrated to each of the 16 healthy male volunteers with a different genotype (CYP2C9*1/*1, n = 6; CYP2C9*1/*13, n = 4; and CYP2C9*1/*3, n = 6). Blood samples were collected from pre-dose up to 24 h after the drug administration. Plasma losartan and E3174 (an active metabolite of losartan) were assayed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). All the subjects finished the study without adverse drug effects. In the present study, the frequencies of CYP2C9*13 and *13 alleles were 0.6% and 2.6% in Chinese healthy volunteers, respectively, and both alleles were in Hardy-Weinberg equilibrium. Compared with the subjects in the CYP2C9*1/*1 group, individuals carrying the CYP2C9*1/*13 genotype showed significantly a longer t(1/2) of losartan and E3174 and markedly increased the area under the curve (AUC) of losartan. Meanwhile, the CYP2C9*1/*3 genotype group had significant differences in t(1/2) and Cmax of E3174 compared with the CYP2C9*1/*1 group. The ratio of AUC(E3174)/AUC(losartan) after losartan administration in the CYP2C9*1/*13 and CYP2C9*1/*3 groups was also statistically different from that in the CYP2C9*1/*1 group. The data indicate that the presence of the CYP2C9*13 allele results in poor metabolism of losartan after a single oral dose.