MiR-34a targeting on Smad4 plays important role in TGF-β1 pathway which is a dominant factor for balancing collagen production and degradation in hepatic stellate cells. TGF-β1/Smad4 regulated collagen deposition is a hallmark of hepatic fibrosis. The potential regulation on miR-34a by LncRNAs in hepatic stellate cells (HSCs) is still reserved to be revealed. In current study, it was hypothesized that a miR-34a interactor, lncRNA CCAT2 may regulate TGF-β1 pathway in liver fibrotic remodeling. The interaction between CCAT2 and miR-34a-5p was checked by dual luciferase assay. the effects of CCAT2 and miR-34a-5p on cell proliferation and apoptosis were verified by MTT assay, colony formation assay, and flow cytometry assay. Dual luciferase activity showed CCAT2 are targets of miR-34a-5p. Sh-CCAT2 transfection prohibit HSCs proliferation and induce HSCs apoptosis, also inhibited ECM protein synthesis in HSCs. Decreased miR-34a-5p enhanced HSCs proliferation, blocked HSCs apoptosis and promoted ECM protein production. miR-34a-5p inhibitor undo protective regulation of sh-CCAT2 in liver fibrosis. Furthermore, clinical investigation showed that CCAT2 and Smad4 expression level were significantly induced, while miR-34a-5p was significantly decreased in HBV related liver fibrosis serum. In conclusion, activated HSCs via TGF-β1/Smad4 signaling pathway was successfully alleviated by CCAT2 inhibition through miR-34a-5p elevation.

Objective: Addressing the inhibition and reversal of chronic hepatitis B fibrosis is an urgent global challenge, which highlights the critical need to understand its underlying mechanisms. Inhibiting the activation of hepatic stellate cells (HSCs) is an important strategy for fibrosis reversal. In particular, the induction of ferroptosis in HSCs presents a promising avenue for curtailing liver fibrosis. Therefore, this study explores the influence of PR/SET domain 1 (PRDM1), which is a transcriptional regulator, on the progression of liver fibrosis by regulating HSC ferroptosis through glutathione peroxidase 4 (GPX4). Material and Methods: We used protein–protein interaction databases to analyze the interacting proteins of GPX4. The messenger ribonucleic acid levels of PRDM1 and GPX4 in liver tissues with varying degrees of fibrosis were examined using quantitative polymerase chain reaction. Cell lines with interference and overexpression of PRDM1/GPX4 were established. Reactive oxygen species (ROS) activity, malondialdehyde (MDA) concentration, cell proliferation capacity, as well as the expression levels of GPX4, a-smooth muscle actin, vimentin, and desmin, were assessed to investigate the relationship between PRDM1 and hepatic fibrosis, as well as its impact on ferroptosis in HSCs. Results: A significant negative correlation was observed between the transcriptional regulator PRDM1 and GPX4. As the degree of fibrosis worsened, PRDM1 decreased significantly, whereas GPX4 increased significantly. The overexpression of PRDM1 markedly increased ROS and MDA concentrations, but it decreased cell proliferation capacity, GPX4 expression levels, and activation marker protein levels. Interference with PRDM1 yielded opposite results. The expression level of GPX4 did not affect PRMD1 expression levels. Compared with cells with single interference of PRDM1, simultaneous interference with PRDM1 and GPX4 significantly inhibited the activity and proliferation capacity of HSCs. It also elevated ROS activity and MDA concentrations. When ferroptosis inhibitors were added, ROS activity and MDA concentrations decreased, and the proliferation capacity and activity of HSCs increased. Opposite results were obtained when PRDM1 and GPX4 were overexpressed simultaneously. Conclusion: PRDM1 is implicated in the occurrence and progression of hepatic fibrosis. It may act as an upstream regulatory factor of GPX4, which exerts control over ferroptosis by suppressing the transcription of GPX4. Ultimately, the activation of HSCs is promoted.

Introduction: Viral hepatitis, caused by various hepatitis viruses, is a global health threat leading to chronic liver disease, hepatic cirrhosis, hepatic failure, and hepatocellular carcinoma. Smoking, a known risk factor for numerous chronic diseases, has been implicated in the pathogenesis...