Effect of Substance P on Differentiation of Bone Marrow Stromal Stem Cells Under Oxidative Stress

Bone marrow stromal stem cells (BMSCs) can be used to treat bone defects but BMSCs are damaged under oxidative stress. The neuropeptide substance P (SP) involves various cellular activities. However, SP's role in BMSCs differentiation under oxidative stress is unknown. Rat BMSCs were isolated and assigned into control group; oxidative stress group treated with 200 mu M H2O2; and SP group, in which 10 mM SP was added under oxidative stress followed by analysis of SP secretion by ELISA, cell proliferation by MTT method, Caspase3 activity, Bax and Bcl-2 level by Real time PCR, ALP activity ROS and SOD content as well as NF-kappa B level by Western blot. Under oxidative stress, SP secretion was significantly decreased, BMSCs proliferation was inhibited, Caspase3 activity and Bax expression increased, Bcl-2 and ALP activity was decreased along with increased ROS activity and NF-kappa B level and reduced SOD activity (P<0.05), adding SP to BMSCs under oxidative stress can significantly promote SP secretion and cell proliferation, reduce Caspase3 activity and Bax expression, increase Bcl-2 expression and ALP activity, decreased ROS activity and NF-kappa B level, and elevated SOD activity (P < 0.05). SP secretion from BMSCs cells was reduced under oxidative stress. Up-regulation of SP in BMSCs cells under oxidative stress can inhibit BMSCs apoptosis and promote cell proliferation and osteogenesis by regulating NF-kappa B.