The miR-3074/BMP7 axis regulates TGF-β-caused activation of hepatic stellate cells in vitro and CCl4-caused murine liver fibrosis in vivo

Abstract

Continuously progressive hepatic fibrosis might cause chronic liver diseases, resulting in hepatic failure. The activation of hepatic stellate cells (HSCs) residing in the liver might induce and influence hepatic fibrosis. In the present study, microRNA 3074 (miR-3074) was found increased within transforming growth factor-β (TGF-β)-activated HSCs and enriched within the TGF-β signaling. In activated HSCs by TGF-β, miR-3074 overexpression aggravated TGF-β-induced fibrotic changes, whereas miR-3074 inhibition exerted opposite effects. miR-3074 directly targeted bone morphogenetic protein 7 (BMP7) and inhibited BMP7 expression. Under TGF-β induction, overexpressed BMP7 notably attenuated the promotive roles of miR-3074 overexpression in TGF-β-activated HSCs. Within carbon tetrachloride (CCl₄)-caused liver fibrosis murine model, miR-3074 agomir administration promoted, while LV-BMP7 administration alleviated CCl₄-induced fibrotic changes; LV-BMP7 significantly attenuated the effects of miR-3074 agomir. Lastly, mmu-miR-3074 also targeted mouse BMP7 and inhibited mouse BMP7 expression. In conclusion, the miR-3074/BMP7 axis regulates TGF-β-caused activation of HSCs in vitro and CCl₄-caused murine liver fibrosis in vivo. BMP7-mediated Smad1/5/8 activation might be involved.

Keywords: BMP7; Hepatic fibrosis; Hepatic stellate cells (HSCs); TGF-β/Smad signaling pathway; miR-3074.