This study explored the mechanism of microRNA (miR)-30a in the activation of hepatic stellate cells (HSCs) to deepen the understanding of the pathogenesis of liver fibrosis. Subsequent to knockdown and ectopic experiments, HSCs were induced with 10 ng/mL transforming growth factor (TGF)-β1 to inspect the role of the miR-30a/TGF-β receptor 1 (TGFBR1) axis in HSC proliferation and activation. qRT-PCR was utilized to examine TGFBR1 mRNA and miR-30a expression and western blot to test TGFBR1, alpha smooth muscle actin (α-SMA), Collagen I and mothers against DPP homolog 2/3 (Smad2/3) protein expression. The fluorescence intensity of α-SMA was measured with immunofluorescence staining. The interaction of TGFBR1 with miR-30a was tested with a dual-luciferase reporter assay. TGF-β1 treated HSCs had upregulated expressions of α-SMA and Collagen I. In addition, downregulated miR-30a, upregulated TGFBR1 and activated TGF-β1/Smad2/3 pathway were found in activated HSCs. Upregulation of miR-30a or downregulation of TGFBR1 suppressed the activation and growth of HSCs. miR-30a repression activated the TGF-β1/Smad2/3 pathway and promoted HSC proliferation and activation, while suppression of TGFBR1 revered these effects. miR-30a was an upstream regulatory factor of TGFBR1. miR-30a blocks the TGF-β1/Smad2/3 pathway to inhibit HSC activation against liver fibrosis by targeting TGFBR1.
Keywords: Liver fibrosis; TGF-β1/Smad2/3 pathway; TGFBR1; hepatic stellate cell activation; microRNA-30a.