To Explore The Mechanism Of Baicalin In Protecting Endothelial Cells From Apoptosis Induced By Ox-LDL With The Theory Of Toxic Heat Injury

Objective: To create a model of the ox-LDL-induced rat aortic endothelial cellapoptosis,and observe the effects of baicalin on cell apoptosis and related proteinexpression.To explore the possible mechanism of baicalin in protecting endothelial cellsand the promising effect of FGF21in the development of AS.Method: Exacuate the male Wistar rats thoracic aorta, then culture the tissue to gainprimary aortic endothelial cells and identify the cells.The cells are divided into normalcontrolling group,baicalin group,ox-LDL stimulating group and baicalin+ox-LDLco-stimulating group.Each group was stimulated for24hours.After the stimulation,Apoptosis of cells was determined by flow cytometry,the expression of FGF21、Bax、Bcl-2、Caspase-3mRNA was messured by RT-PCR method,and the related proteinexpression was messured by enzyme-linked immunosorbent assay (ELISA).Result:(1) Compared with the normal control group, ox-LDL significantly increasedendothelial cell apoptosis in a concentration-dependent manner（P<0.01）, Baicalinsignificantly reduced apoptosis of endothelial cells, also showed a concentration-dependent（P<0.01）.Besides,if we use baicalin to pretreat the cells,we can observe that the cellapoptosis is greatly reduced compared to the same concentration of ox-LDL stimulation（P<0.01），but higher than the normal group（P<0.01）.(2) Compared with the normalcontrol group,ox-LDL can increase the expression of FGF21、Bcl-2,but the Caspase-3andBax was significantly increased（P<0.01）. Baicalin can significantly increase theexpression of FGF21、Bcl-2,and reduce Caspase-3and Bax expression（P<0.01）. If we usebaicalin to pretreat the cells,and use ox-LDLto stimulate the cell after that,we can also conclude the same result.Conclusion: ox-LDL can increase the expression of Caspase-3、Bax to induce theapoptosis of arterial endothelial cells and the increased FGF21and Bcl-2expression maybe a compensatory response of cells against apoptosis；Baicalin can resist the cell damagecaused by ox-LDL,the mechanism may be increasing the expression of FGF21and Bcl-2and reduce the expression of Caspase-3and Bax,which is associated with the inhibition ofcell apopotosis.