Hepatic stellate cell-derived exosome miR-122-5p targets TNFRSF19 to inhibit EMT and fibrosis in intrahepatic biliary epithelial cells via the p38 MAPK pathway

Abstract

Abstract Background and aim: Primary biliary cholangitis (PBC) is a kind of autoimmune mediated chronic cholestatic liver disease, Intrahepatic biliary epithelial cells (IBECs) are the main target cells. The precise effect of miR-122-5p, especially exosomal miR-122-5p in PBC has not been elucidated. Methods: RNA-sequence analyzed the expression profiles of ncRNAs in peripheral blood exosomes of PBC patients. Elisa measured levels of inflammatory cytokines. The proliferation and apoptosis of HIBECs were detected by CCK8 and flow cytometry. Cells were co-cultured using Transwell chamber. The biomarkers of epithelium-mesenchymal transition (EMT), fibrogenesis, and p38 mitogen-activated protein kinase(MAPK) pathway was detected by RT-qPCR and western blot (WB). Dual luciferase reporter assay confirm the binding of miR-122-5p. Results: 8531 differential expressed (DE) lncRNAs and 263 DE miRNAs were identified in serum exosomes of PBC patients. Exosomal miR-122-5p was correlated with liver injury and cholestasis indexes, and combined with gp210 and sp100 could improve the sensitivity of PBC diagnosis. In vitro experiments showed that high expression of miR-122-5p promoted the proliferation, inhibited the apoptosis, EMT and fibrosis of HIBECs. TNFRSF19 is the target gene of miR-122-5p and regulate apoptosis signal-regulated kinase 1 (ASK1). P38 MAPK pathway and inflammatory cytokines were down-regulated by miR-122-5p. Conclusion: miR-122-5p regulates the p38 MAPK signaling pathway by targeting TNFRSF19 and plays an important role in the EMT and fibrosis process of HIBECs. miR-122-5p may be a potential marker for the diagnosis of PBC and therapeutic target.