Effect of miR-23a Overexpression on Chondrogenic and Hypertrophic Differentiation of C3H10T1/2 Cells

Yan Jihong; Gao Hanwei; Yu Rui

Abstract：Objective To investigate the role of microRNA-23a(miR-23a)overexpression in the chondrogenic and hypertrophic differentiation of mouse embryonic mesenchymal stem cell line C3H10T1/2,and to provide new insights for stem cell-based treatment of osteoarthritis and cartilage injury repair.Methods A lentiviral vector overexpressing miR-23a was constructed to infect C3H10T1/2 cells(miR-23a group),with miR-NC-infected cells as the control group(miR-NC group).Transforming growth factor(TGF)-β3 was used to induce chondrogenic differentiation in both groups.Real-time quantitative polymerase chain reaction(RT-qPCR),Western blot,safranin O staining,and immunohistochemistry were performed to detect the expression of cartilage markers[SRY-related high mobility group-box gene 9(SOX9),aggrecan(ACAN),collagen type Ⅱ alpha 1 chain(COL2A1)]and hypertrophy marker[collagen alpha-1(X)chain(COL10A1)].Results During the first 14 days of chondrogenic induction,miR-23a expression continuously increased(P＜0.05),peaking on day 10.Compared with the miR-NC group,the miR-23a group exhibited higher expression of cartilage markers(P＜0.05)and lower expression of the hypertrophy marker(P＜0.05).Further investigation showed that overexpression of miR-23a down-regulated the expression of Runt-related transcription factor 2(Runx2).Conclusion miR-23a is highly expressed in the early stage of chondrogenic differentiation of C3H10T1/2 cells.Overexpression of miR-23a promotes chondrogenic differentiation while inhibiting hypertrophic differentiation,possibly by suppressing the hypertrophy-associated transcription factor Runx2.