Serum microRNA-34a is potential biomarker for inflammation in nonalcoholic fatty liver disease

Abstract

Background: MicroRNA-34a (miR-34a) contributes to liver injury through an apoptosis pathway. Objectives: To determine the correlation between serum miR-34a and liver inflammation as assessed by nonalcoholic fatty liver disease (NAFLD) activity score (NAS). Methods: We included a cross-selectional study of 50 patients with NAFLD in this observational study and confirmed diagnosis by liver biopsy, with NAS grading. A control group comprised 23 healthy individuals without chronic liver disease. Serum miR-34a was assayed using a real-time quantitative PCR (Applied Biosystems). Results: The mean age of NAFLD patients was 46.0 ± 13.7 years, and 52% were female. Metabolic syndrome was found in 76%. Liver histopathology showed that 54% of patients had NAS ≥4 and significant fibrosis (≥F2) was found in 22%. Serum levels of miR-34a were significantly correlated with NAS (r = 0.39, P = 0.005), and the degree of steatosis (r = 0.28, P = 0.049), ballooning (r = 0.30, P = 0.034), and fibrosis (r = 0.39, P = 0.005). Serum miR-34a in patients with NAS ≥4 was significantly higher than in those with NAS <4 (P = 0.011) and controls (P < 0.001). There was no significant correlation between serum miR-34a and other variables. The area under receiver operating characteristic curve for serum miR-34a comparing patients with NAS ≥4 and with NAS <4 was 0.67 (95% CI 0.52, 0.82). Conclusions: Serum level of miR-34a has a significant fair to good correlation with NAS and may serve as a biomarker of liver inflammation and fibrosis in patients with NAFLD.