Background and aim: Nonalcoholic steatohepatitis (NASH) is featured by lipid accumulation, inflammation, and fibrosis. miRNAs are small non-coding RNAs that participate in post-transcriptional genetic regulations and are involved in various pathologies such as NASH. The drug pirfenidone is an antifibrotic, anti-inflammatory and antioxidant agent. Aim: To evaluate the effect of prolonged-release pirfenidone on histological parameters, activation of hepatic stellar cells, expression of hepatic miRNAs and target genes in an experimental model of NAFLD/NASH.
Material and methods: Male C57BL/6J mice were fed a high fat diet (HFD, 60% lipids, 42gr/L sugar in water) for 16 weeks. Prolonged-release pirfenidone (∼300mg/kg/d, PR-PFD) was administered in food from the eighth week to the end of the protocol. α-SMA immunohistochemistry and hematoxylin-eosin, Masson's trichrome and Sirius red staining were made. Hepatic expression of miR-21a-5p, miR-103-3p, miR-34a-5p and IL-1β, TNFα, COL1A1, and SREBP1 genes was determined by qRT-PCR and the transcriptome by microarrays. Statistical significance was determined for parametric data with one-way analysis of variance and Tukey's or Bonferroni post hoc test, and Kruskal-Wallis and Mann-Whitney U test for nonparametric data (Graph Prism 6.0). Ethics Committee registration number: CI00518.
Results: Animals treated with PR-PFD have a decrease in inflammatory nodules, macrosteatosis, fibrosis, collagen and activation of hepatic stellar cells. PR-PFD reduced hepatic expression of miR-21a-5p, miR-34a-5p and miR-103-3p expression showed a tendency of decrease compared to HFD group. PR-PFD decreased IL-1β, TNFα, COL1A1, and SREBP1 expression. Transcriptome analysis showed that 36 genes that participate in lipid transport and antioxidant activity were overexpressed in the treated group compared to HFD group. On the contrary, 52 genes involved in lipid and collagen biosynthesis and inflammatory response were downregulated.
Conclusions: Prolonged-release pirfenidone decreased miR-21a-5p expression, miR-34a-5p and miR-103-3p expression showed a tendency to decrease. PR-PFD exhibited an anti-steatogenic, anti-inflammatory and anti-fibrotic effect in the experimental model of NAFLD/NASH.
Conflicts of interest: The authors have no conflicts of interest to declare.
