miR-706 inhibits the oxidative stress-induced activation of PKCα/TAOK1 in liver fibrogenesis

Sci Rep. 2016 Nov 23:6:37509. doi: 10.1038/srep37509.

Abstract

Oxidative stress induces the activation of liver fibrogenic cells (myofibroblasts), thus promoting the expression of fibrosis-related genes, leading to hepatic fibrogenesis. MicroRNAs (miRNAs) are a new class of small RNAs ~18-25 nucleotides in length involved in post-transcriptional regulation of gene expression. Wound-healing and remodeling processes in liver fibrosis have been associated with changes in hepatic miRNA expression. However, the role of miR-706 in liver fibrogenesis is currently unknown. In the present study, we show that miR-706 is abundantly expressed in hepatocytes. Moreover, oxidative stress leads to a significant downregulation of miR-706, and the further reintroduction of miR-706 inhibits oxidative stress-induced expression of fibrosis-related markers such as α-SMA. Subsequent studies revealed that miR-706 directly inhibits PKCα and TAOK1 expression via binding to the 3'-untranslated region, preventing epithelial mesenchymal transition. In vivo studies showed that intravenous injection of miR-706 agomir successfully increases hepatic miR-706 and decreases α-SMA, PKCα, and TAOK1 protein levels in livers of carbon tetrachloride (CCl4)-treated mice. In summary, this study reveals a protective role for miR-706 by blocking the oxidative stress-induced activation of PKCα/TAOK1. Our results further identify a major implication for miR-706 in preventing hepatic fibrogenesis and suggest that miR-706 may be a suitable molecular target for anti-fibrosis therapy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Carbon Tetrachloride / toxicity
  • Disease Models, Animal
  • Gene Expression Regulation / genetics
  • Hepatocytes / metabolism
  • Hepatocytes / pathology
  • Humans
  • Liver / drug effects
  • Liver / pathology
  • Liver Cirrhosis / chemically induced
  • Liver Cirrhosis / genetics*
  • Liver Cirrhosis / pathology
  • Mice
  • MicroRNAs / genetics*
  • Oxidative Stress*
  • Protein Kinase C-alpha / genetics*
  • Protein Serine-Threonine Kinases / genetics*
  • Signal Transduction / genetics

Substances

  • MIRN706 microRNA, human
  • MIRN706 microRNA, mouse
  • MicroRNAs
  • Carbon Tetrachloride
  • Protein Serine-Threonine Kinases
  • TAO1 protein kinase
  • Protein Kinase C-alpha