Effects Of Calycosin From Astragalus Membranaceus On DNA Damage Of Vascular Endothelial Cells

Objective Chronic Kidney Disease (CKD) has been a serious public health problem as a killer to human health. How to prevent and treat CKD is still a formidable problem.It is reported that the damage of vascular endothelial cell which is the basic structure of glomeruli of kidney may accelerate the deterioration for CKD, and the DNA damage is one of factors to induce the diease.So, this study aimed to create a damage model for vascular endothelial cell in vitro, to observe the changes of DNA damage' production,to explore protective effects of calycosin to DNA damage of vascular endothelial cells,which provided a convincing and scientifical evendence to use the calycosin to cure CKD.Methods Human umbilical vein endothelial cells (HUVECs) cultured in vitro were randomly divided into five groups, control, TNF-a 80ng/ml, TNF-a 80ng/ml+calycosin O.lmg/L, TNF-a 80ng/ml+calycosin lmg/L,TNF-a 80ng/ml+calycosin 10mg/L. Cells in every group were interfered with TNF-αor TNF-α+ calycosin for 8hours,16hours and 24hours. 8-hydroxy-2'-deoxyguanosine (8-OHdG) as a biomarker of DNA damage was detected by ELISA and DNA damage indices of tail length, tail moment and olive tail moment were analyzed by single cell gel assay.Results①Compared with control, the indices of 8-OHdG increased greatly(8h:9.09±0.55 vs 11.66±0.43;16h:9.09±0.55 vs 13.93±0.68; 24h:9.09±0.55 vs 14.45±1.09, P<0.05),and tail length, tail moment and olive tail moment increased significantly in TNF-a group(P<0.05);②Compared with TNF-αgroup, the indices of cells pretreated with calycosin have significant differences in group TNF-α+calycosin 1mg/L and TNF-α+calycosin 10mg/L (8-OHdG 8h: 11.66±0.43 vs 10.76±0.21,11.66±0.43 vs 10.13±0.24,16h:13.93±0.68 vs 11.35±0.64,13.93±0.68 vs 10.19±0.83,24h:14.45±1.09 vs 11.49±0.35.14.45±1.09 vs 10.43±0.44, P<0.05) except group of TNF-α+calycosin0.1mg/L (P>0.05);③Every group of pretreated with calycosin has significant differences comparing with each others (P<0.05);④Compared with different time,it has significant differences for TNF-a group and it has obvious DNA damage(P<0.05) Conclusion Calycosin from Astragalus membranaceus may play an important role in protecting TNF-α-induced damage of vascular endothelial cells, and with the improving of calycosin' concentration the effect was strengthened obviously. The protective effect is possible associated with the reduction of DNA damage.