Salicylideneamino-2-thiophenol enhances osteogenic differentiation through the activation of MAPK pathways in multipotent bone marrow stem cell.

Osteoporosis is a reduction in skeletal mass due to an imbalance between bone formation and bone resorption. Therefore, the identification of specific stimulators of bone formation is of therapeutic significance in the treatment of osteoporosis. Salicylideneamino-2-thiophenol (Sal-2) consists of two benzene rings, has been reported to possess antioxidant activity, and is an effective remedy for fever and rheumatic diseases. However, until now the effects of osteoblastic bone formation by Sal-2 were unknown. In this study, we investigated the effects of Sal-2 on osteogenic differentiation of multipotent bone marrow stromal stem cells by alizarin red S staining for osteogenic differentiation, RT-PCR and western blot for alkaline phosphatase (ALP) activity and signaling pathways, FACS analysis and immunofluorescence staining for CD44 and CD51 expression, calcium assays, and immunofluorescence staining for signaling pathways. We found that Sal-2 enhanced the osteogenic differentiation of multipotent bone marrow stromal stem cells. Sal-2 treatment induced the expression and activity of ALP, and enhanced the levels of CD44 and CD51 expression as well as Ca2+ content, in multipotent bone marrow stromal stem cells. Moreover, we found that Sal-2-induced osteogenic differentiation and expression of osteogenesis-related molecules involve the activation of the MAPK and nuclear factor-κB pathways. Our findings provide insight into both the mechanism and effects of Sal-2 on osteogenic differentiation and demonstrate that Sal-2 may be a beneficial adjuvant in stimulating bone formation in osteoporotic diseases.