The Protective Effect Of Salvianolic Acid B In Ischemia Anoxic Conditions-induced Apoptosis Of Bone Marrow Mesenchymal Stem Cells

Background: Stem cell therapy for myocardial infarction is one of the hot spots in the world. Bone marrow mesenchymal stem cells( BMSCs) are widely concerned and studied due to the self-renewal and multiple differentiation potential. However, stem cell transplantation is also facing a series of severe challenges, most of the transplanted cells will be apoptosis and lost within a few days after transplantation, only a small part can play its biological role. Therefore, how to improve the survival rate of transplanted cells is the urgent problem need to be solved in the process of stem cell transplantation. Salvianolic acid B(SalB) as the water soluble extract of Salvia miltiorrhiza has the function of anti-oxidation, anti-apoptosis, reversing the ventricular remodeling, which also has a protective effect on the occurrence and development of cardiovascular disease. The effect of SalB on the survival of BMSCs under the ischemia anoxic conditions needs further studied.Objective: By simulating the ischemia anoxic conditions of infarction area after myocardial infarction, the experiment examined the effect of Salvianolic acid B in ischemia anoxic conditions-induced apoptosis of bone marrow mesenchymal stem cells, thus to seek the better way for reducing cell apoptosis after transplantion.Methods: Bone marrow mesenchymal stem cells were isolated from 6 weeks SD rat(150-180g) and cultured by whole bone marrow adherent cultivation method, and were extracted for primer culture and passged. BMSCs were randomly divided into five groups: normal control group, ischemia anoxic group, different concentrations of SalB(0.1mg/L、1mg/L、10mg/L) pretreatment and ischemia anoxic group. The apoptotic cells observered by fluorescent dyeing Hoechst 33342, The expression of Bcl-2 and Bax were detected respectively by Western blotting and RT- PCR.Results: Compared with normal control group, ischemia anoxic group cells appeared obvious apoptosis phenomenon(P<0.01). Compared with ischemia anoxic group, the apoptosis cells of SalB pretreatment group significantly reduced(P<0.01),the Bcl-2 expression increased and the Bax expression decreased in BMSCs(P<0.01), the Bcl-2/Bax ratio were increased(P<0.01). Among them, 1mg/L SalB group expressed the Bcl-2 and the Bax was more significantly than 0.1mg/L group(P<0.01), but there was no difference between 1mg/L group and 10mg/L group(P>0.05).Conclusion: The ischemia anoxic environment can induce BMSCs apoptosis, SalB pretreatment can improve the BMSCs’ ablitily of anti-apoptosis under ischemia anoxic conditions. The mechanism may be related by elevating the expression of anti-apoptotis gene Bcl-2 and inhibiting the expression of pro-apototosis gene Bax.