Regulation of antler stem cell exosomes miRNA-145 on inflammatory chondrocytes

Jiang Yidi; Zhao Jianwei; Zhou Jue; Lyu Jinpeng; Wang Datao; Li Xunsheng; Yue Zhigang; Cui Bo; Sun Hongmei

doi:10.12307/2026.322

Abstract：BACKGROUND:In recent years,the research on the role of stem cell exosomes in the treatment of arthritis has attracted more and more attention.In the early stage,our research group found that the secretion of antler stem cells has the potential to repair cartilage injuries,but its specific function is still unclear. OBJECTIVE:To explore the regulatory role and mechanisms of antler stem cell exosomes miRNA-145 in chondrocyte injury repair. METHODS:A lentiviral vector system was employed to establish the antler stem cells overexpressing miRNA-145.Exosomes were extracted from these cells using ultracentrifugation.Rat chondrocytes were divided into five groups:blank control group,interleukin 1β group,exosomes+interleukin 1β group,empty vector transfected exosomes+interleukin 1β group,and miRNA-145 transfected exosomes+interleukin 1β group.Except for the blank control group,the chondrocytes in the other four groups were induced with interleukin 1β for 24 hours to establish an inflammatory cell model,and then treated with corresponding exosomes.CCK-8 assay was used to detect the cell proliferation level.The scratch test was used to detect the cell migration ability.qPCR and western blot assay were used to detect the expression levels of chondrocyte-related genes and proteins. RESULTS AND CONCLUSION:(1)The exosomes exhibited a typical oval double-layer vesicle structure with diameters ranging from 50 to 150 nm,all of which expressed classical markers of exosomes,such as CD9,ALIX,and TSG101,and none of them expressed Calnexin.(2)Antler stem cell exosomes enhanced chondrocyte viability,cell mobility,type Ⅱ collagen A1,transforming growth factor β1,SMAD3,SOX9 mRNA and protein expression levels,and reduced matrix metalloproteinase 13 mRNA expression level in the inflammatory environment.(3)miRNA-145 further decreased chondrocyte viability,cell mobility,type Ⅱ collagen A1,transforming growth factor β1,SMAD3,SOX9 mRNA and protein expression,and further increased matrix metalloproteinase 13 mRNA expression in the inflammatory environment.(4)These results conclude that antler stem cell exosomes can promote chondrocyte repair through the transforming growth factor β1/SMAD3 signaling pathway,and overexpression of miRNA-145 inhibits chondrocyte repair.