The Effect Of Lycopene On Osteoblasts Which Have Incurred Oxidative Stress

Objective Osteoporosis is one of the most common human disease,and its etiologic factors are unclear.It has been certified recently that oxidative stress evoked by active oxygen is one of its factors.This investigation examine the effects of lycopene-a potent antioxidant on osteoblasts which have incurred oxidative stress.The proliferation,differentiation,secretion,and mineralization of osteoblasts are detected. Methods After enzyme digestion, isolation, purified osteoblasts of SD rat are cultured for further study.The cells of the third generation are exposed to the medium containing low carbohydrates,0.1mmol/L H₂O₂,10%FBS for 24 hours.Then the cells are divided into 4 groups in random: the control group,the groups treated by 10^-6mol/L,5×10^-6mol/L,10^-5mol/L lycopene.After 72 hours of culture, the following study are continued.(l)The proliferation of the cells is detected by MTT way.(2)The proliferation index (PI) of osteoblasts in each group is determined by Flow CytoMeter.(3) The expression of alkaline phosphatase in each group is measured in pNPP method.(4) The expression change of collagen I is detected by Western blotting.(5)The cells are cultured in the medium containing 50μg/ml vitamin C, 10mmol/L sodium glycerophosphate and the medium is changed every 3 days.4 weeks later,the mineral nodes of osteoblasts are dyed in alizarin red and improved Von kossa way,then counted.Results (1)The MTT absorbency at 590nm in the experimental groups are higher than in the control group,p<0.01.(2)Lecopene at 10^-6mol/L,5×10^-6mol/L,10^-5mol/L can increase the proliferation index (PI) of osteoblasts,p<0.01.(3) The pNPP absorbency at 405nm in the experimental groups are higher than that in the control group.the absorbency of 10^-5mol/L lycopene group is the highest, p<0.01.(4)As the Western-blot result,the pretain band of 5×10^-6mol/L.10^-5mol/L lycopene group is wider than the cntrol group,which indicates an increase in the expression of collagen I .(5)Each experimental group can produce more mineral nodes than the control group,p<0.01.Conclusion Lecopene has the effects on stimulating the proliferation,differentiation, secretion and mineralization of osteoblasts which have incurred oxidative stress.