NTG Enhances Proliferation And Osteoblastic Differentiation In Human Mesenchymal Stem Cells Via NO Pathway

Aim: To investigate the effect of nitroglycerin (NTG), on the proliferation and osteoblastic differentiation of human bone marrow-derived mesenchymal stem cells (HBMSCs) and its mediation mechanisms.Methods: HBMSCs were cultured in osteogenic differentiation medium, consisting of a-MEM plus 10 % FBS supplemented with 10 nmol·L^-1 dexamethasone, 50mg/L ascorbic acid and 10 mmol·L^-1β-glycerophosphate, and treated with 0.1μM-10μM NTG with or without different antagonists. The BrdU incorporation was measured, which reflected cell proliferation, by a BrdU cell proliferation Assay kit. The osteoblastic differentiation in HBMSCs was assessed by determination of cellular alkaline phosphatase (ALP) activity and calcium deposition. The NO production of the cell treated with nitroglycerin was detected to make sure the influence of NTG on the NO pathway in the cells, and the relation between the NO content and the ALP activity or the calcium deposition.Results: Treatment with NTG (0.1μM-10μM) dose-dependently increased the NO production, and the proliferation of the cells, while 0.5μM-10μM NTG promoted ALP activity and calcium deposition in HBMSCs cultures. These stimulatory effects of NTG (10μM) couldn't reduced by either L-NAME, an antagonist of eNOS, or 1400W, an inhibitor blocking the iNOS activity.Conclusion: NTG stimulated the proliferation and osteoblastic differentiation of HBMSCs through NO pathways, which was independent on either eNOS or iNOS.