MiR-484 Knockdown Ameliorates Liver Fibrosis by Blocking Wnt/ß-catenin Pathway via Tar-geting HIPK1

Liver fibrosis is a common pathological process of various chronic liver diseases that can develop into liver cancer. MicroRNAs (miRNAs) are a king of non-coding RNA which are closely related to liver diseases. Thus, this research hope to explore the effect of miR-484 on liver fibrosis and reveal its mechanism. The miRNAs profiles were screened by microRNA sequencing and the location of miR-484 was identified by fluorescence in situ hybridization (FISH) in human liver fibrotic tissues. MiR-484 expression was detected by qRT-PCR in rat primary hepatic stellate cells (HSCs). Bioinformatics analysis and dual-luciferase reporter assay were performed to determine the target gene of miR-484. Liver fibrosis specific signatures were analyzed by qRT-PCR and western blot after miR-484 mimic/inhibitor transfection. The cell apoptosis was detected by Annexin V-FITC/PI double staining. The effect of miR-484 silencing on fibrosis in vivo was investigated in thioacetamide (TAA) induced mice model using the adeno-associated virus carrying miR-484 inhibitor. Enrichment of miR-484 was observed in human liver fibrosis tissues and activated rat primary HSCs. FISH showed that miR-484 was prominently located at fibrotic region and the cytoplasm of HSCs in human liver tissues. Dual-luciferase reporter assay verified that the homeodomain-interacting protein kinases 1 (HIPK1) was the direct target of miR-484. After transfecting miR-484 inhibitor into HSC-T6, HIPK1 were significantly up-regulated, and a-SMA, col1a1, Wnt-3a, Wnt-5a, ß-catenin and p-ß-catenin were down-regulated, suggesting the restrain effect of miR-484 knockdown on HSCs activation. Conversely, the results were opposite with miR-484 mimic transfection. In addition, the apoptosis of HSC-T6 altered significantly after miR-484 modulation. Moreover, adeno-associated virus carrying miR-484 inhibitor alleviated mice liver fibrosis induced by TAA. In conclusion, miR-484 knockdown ameliorates liver fibrosis by promoting the apoptosis and suppressing HSCs activation via blocking Wnt/ß-catenin signaling pathway. MiR-484 and its downstream gene HIPK1 might be selected as novel therapeutic targets of liver fibrosis. Overall design: six human liver fibrotic tissues (provided by the Second Affiliated Hospital of Naval Medical Universi-ty, Shanghai, China) were gathered and sent for miRNA sequencing (Lc-bio technologies, Hangzhou, China).