TGF-β2通过增加线粒体活性氧积累和阻滞细胞周期促进猪间充质干细胞衰老OA

This study aimed to investigate the role and mechanism of transforming growth factor-beta 2(TGF-β2)in the senescence of porcine bone marrow mesenchymal stem cells(pBMMSCs).First,changes in TGF-β2 levels during in vitro replicative senescence of pBMMSCs were analyzed.Then,the effects of TGF-β2 at concentrations of 1 ng/mL,10 ng/mL,and 100 ng/mL on cell growth,proliferation,senescence,mitochondrial reactive oxygen species(mtROS)levels,cell cycle,and related gene expression were also examined.The results showed that pBMMSCs expressed stem cell markers CD90 and CD44,and had the potential for adipogenic and osteogenic differentiation.With increasing passage numbers,the mRNA levels of TGF-β2 significantly increased,and its protein content rose from(41.97±9.46)pg/mL to(77.04±3.44)pg/mL.After TGF-β2 treatment,cell proliferation ability decreased,the number of senescent cells significantly increased,mtROS levels were elevated,and the cell cycle was arrested at G1 phase.Moreover,the expression of OCT4,Ki67,PCNA,and SOD2 was downregulated,while the expression of P53 and P21 was upregulated.These findings indicated that TGF-β2 in-duced the aging of pBMMSCs by promoting mtROS accumulation and causing G1-phase cell cycle arrest.This study pro-vides new insights into the role of TGF-β2 in the senescence process of mesenchymal stem cells.