Effect of Mir-663 on the Differentiation of Bone Marrow Mesenchymal Stem Cells in Inflammatory Environment Through Regulating Oxidative Stress and Transforming Growth Factor β1

Abstract

BMSCs are beneficial for the treatment of Osteoarthritis (OA). Mir-663 involves in various diseases. However, the role of Mir-663 in the differentiation of BMSCs in an inflammatory environment remains unclear. Rat BMSCs were isolated and divided into control group, and inflammation group which was treated with 1 μg/ml lipopolysaccharide (LPS), Mir-663 group and Mir-663 siRNA groups which was respectively transfected with Mir-663 plasmid and Mir-663 siRNA into LPS-treated BMSCs followed by analysis of the survival rate of BMSC by MTT, Caspase 3 activity, ALP activity, expression of osteogenic genes Runx2 and OP by Real time PCR, ROS content and SOD activity, TGF-β1 level by Real time PCR and ELISA, TNF- and IL-1 secretion by ELISA. LPS treatment significantly increased Mir-663 expression, inhibited cell proliferation, increased Caspase 3 activity, and inhibited ALP activity. Meanwhile it also significantly decreased Runx2 and OP expression, increased ROS content, decreased SOD activity and TGF-β1 expression as well as elevated TNF-α and IL-1β secretion compared to control (P < 0.05); Mir-663 plasmid transfection can further promote the above changes (P < 0.05); whereas, Mir-663 siRNA could reverse the above changes (P < 0.05). Mir-663 expression was increased in BMSCs in inflammatory environment. Down-regulation of Mir663 expression can regulate oxidative stress, up-regulate TGF-β1 level, inhibit the secretion of TNF-α and IL-1β, and promote the proliferation and osteogenic differentiation of BMSCs in inflammatory environment.