To determine the role of mRNA and lnc-RNA in the osteogenic differentiation of MSC with strain stimulation.

MSC from healthy donors were isolated, cultured and then divided into the experimental group and the control group. The experimental group was stimulated with strain using FlexCell system (5﹪, 0.1?Hz, 4?h/d), and the control group was cultured without stimulaiton. The osteogenic differentiation ability of MSC was detected by alizarin red and alkaline phosphatase assays. RNA was extracted on day 7 of osteogenic differentiation, which was then detected using the mRNA and lnc-RNA expression microarrays. The key lnc-RNAs were identified using bioinformatics technology.

On day 14 of osteogenic differentiation, the ARS quantitation results of MSC in the strain stimulation group (OD value: 1.46±0.19) were higher than those of the control group (OD value: 0.62±0.08). The difference was statistically significant (t?= -1.99, P < 0.05). Besides, the ALP activity results of MSC in the strain stimulation group (265.3±31.2)?U/L were also higher than MSC without strain stimulation (121.2±21.2)?U/L (t?= -12.23, P < 0.05) . Through microarray dection, a total of differentially expressed 598 mRNAs and 329 lnc-RNAs were identified on day 7 of osteogenic differentiation. KEGG analysis showed that WNT signal pathway was the key pathway with the most significant differences, among which WNT5a had the largest change. Co-expression analysis suggested that lnc-RNA-SSR may be the critical lnc-RNA to regulate WNT5a expression.

Expression profile of mRNA and lnc-RNA in MSC significantly changed with strain stimulation. Lnc-RNA-SSR may affected MSC osteogenesis through regulating WNT5a expression with strain stimulation