Lnc-RNA BLACAT1 regulates differentiation of bone marrow stromal stem cells by targeting miR-142-5p in osteoarthritis.

OBJECTIVE Osteogenic differentiation of bone marrow stromal stem cells (BMSCs) is beneficial to the treatment of osteoarthritis (OA). Lnc-RNA BLACAT1 involves in occurrence and development of various diseases. However, the role of Lnc-RNA BLACAT1 in BMSCs differentiation under inflammation remains unclear. MATERIALS AND METHODS Rat BMSCs were isolated and randomly divided into control group and inflammation group (addition of IL-6). The inflammation group was further divided into BLACAT1 siRNA group and BLACAT1 siRNA+miR-142-5p inhibitor group, followed by analysis of Lnc-RNA BLACAT1 expression by real time PCR, BMSCs proliferation, Caspase 3 activity, ALP activity, expression of Runx2, OC and PPARγ2 by real time PCR, and secretion of TNF-α and IL-1β by enzyme-linked immunosorbent assay (ELISA). The bioinformatics software and the Luciferase reporter system analyze the targeted relationship between BLACAT1 and miR-142-5p. RESULTS In inflammation group, Lnc-BLACAT1 expression was increased, along with inhibited BMSCs proliferation, increased Caspase 3 activity, decreased ALP activity, and expression of Runx2 and OC, increased PPARγ2 expression and secretion of TNF-α and IL-1β. The difference was statistically significant compared with control group (p<0.05). MiR-142-5p is the target miRNA of Lnc-RNA BLACAT1. BLACAT1 siRNA down-regulated BLACAT1 expression, promoted cell proliferation, inhibited Caspase 3 activity, increased ALP activity and Runx2 and OC expression, decreased PPARγ2 expression and TNF-α and IL-1β secretion. Compared with inflammation group, the difference was statistically significant (p<0.05). Of note, BLACAT1 siRNA+miR-142-5p inhibitor group reversed the effect of siRNA-mediated knockdown of BLACAT1. CONCLUSIONS Lnc-RNA BLACAT1 expression was increased in inflammatory BMSCs, and knockdown of BLACAT1 promoted proliferation and osteogenic differentiation of BMSCs targeting miR-142-5p.