二甲双胍通过激活线粒体自噬抑制人肺成纤维细胞的活化OA

Objective To explore the effect of metformin on pulmonary fibrosis and clarify the mechanism by which met-formin regulates mitophagy to inhibit the activation of human lung fibroblasts.Methods Human lung fibroblasts were induced by 10 ng/mL transforming growth factor beta 1(TGF-β1)to establish a fibrosis cell model,and then treated with 2 mmol/L metformin for 24 hours.Western blot and ELISA experiment were used to detect fibrosis markers alpha-smooth muscle actin(α-SMA),Alpha-1 type Ⅰcollagen(Col1α1),and interleukin-6(IL-6).The mitophagy pathway was determined by transcriptome data analysis(GSE264038),and the mitophagy-related proteins PTEN-induced kinase 1(PINK1),Parkin and p62 were detected by Western blot.After pretreat-ment with the autophagy inhibitor SBI-0206965,fibrosis markers were detected again.Results Western blot and ELISA experiment results demonstrated that TGF-β1 successfully induced a fibrotic model in human lung fibroblasts,as evidenced by significantly upregu-lated expression levels of α-SMA,Col1α1,and IL-6.Compared with the TGF-β1 model group,the group treated with TGF-β1 com-bined with metformin showed markedly reduced α-SMA expression,Col1α1 and IL-6 secretion,indicating that metformin intervention significantly reversed the fibrotic phenotype.Transcriptomic analysis revealed an association between metformin and the activation of the mitophagy pathway.Further validation by Western blot and ELISA experiments confirmed that metformin activated the mitophagy path-way,manifested by synchronous increases in the protein expression of PINK1,Parkin,and p62.After inhibiting mitophagy in human lung fibroblasts by pretreatment with the autophagy inhibitor SBI-0206965,the expression levels of α-SMA,Col1α1,and IL-6 were in-creased in the SBI-0206965 pretreatment group compared to the TGF-β1 plus metformin group,suggesting that the anti-fibrotic effect of metformin was partially attenuated.Conclusion Metformin inhibits the activation of human pulmonary fibroblasts by activating PINK1/Parkin mediated mitophagy,which may provide a new target for the treatment of pulmonary fibrosis.