Puerarin Alleviates Radiation-induced Injury Of Vascular Endothelial Cells Via Targeted Regulation Of PGF By MiR-34a

Background The medical radiation exposure is associated with substantial risk for the subsequent development of cardiovascular disease and the vascular endothelium is believed to be a target of radiation-induced injury.Alleviating the damage is one of the most important ways to prevent or treat the corresponding cardiovascular complications.Puerarin has been wildly used in medical treatment because of its abundant biological functions.As reported,puerarin also has a protective effect on radiation-induced damage.However,the mechanism is still unknown.Objective The aim of this study was to investigate the protection of puerarin for irradiation and the mechanism.Method The Cell Counting Kit-8(CCK8)was used to detect the cytotoxicity of puerarin to human umbilical vein endothelial cells(HUVECs).To establish the model that puerarin cloud attenuate the radiation-induced injury,HUVECs were exposed to different radiation doses and then treated with different concentrations of puerarin.Finally,we decide the most suitable radiation dose(10Gy),puerarin concentration(20umol/L)and sampling time(48h)in the light of the cell viability that CCK8 showed.Apoptosis was investigated using the flow cytometric analysis of Annexin V-FITC/PI staining and the expression of caspase-3 weighed by western-blot.The Comet assay and γ-H2 AX expression were used to measure DNA damage and repair.Expression of PGF and miR-34 a in HUVECs were determined by qRT-PCR and western-blot.Luciferase assay was used to verify whether PGF was a target gene of miR-34 a.The expression of PGF in whole blood of cancer patients was detected by qRT-PCR and the concentrations of PGF and sVCAM-1 in serum were measured using ELISA.Results Compared with the control group,exposure of HUVECs to 10 Gy X-ray for 48 hours resulted in significant increase in DNA damage and apoptosis,which were attenuate by co-incubation with puerarin(20umol/L).The expression of mi R-34 a and PGF were up-regulated in HUVECs when treated with radiation.However,the expression of miR-34 a decreased when treated with radiation plus puerarin and the expression of PLGF increase further when compared with the group of radiation alone and radiation plus glucose.MiR-34 a could directly bind to the 3’UTR of PGF mRNA and suppress the expression of PGF.The expression of miR-34 a increased with the increasing cumulative radiation dose in whole blood of cancer patients undergoing radiation therapy and the expression of PGF decreased.Meanwhile,the concentrations of c VCAM-1 in the serum of radiotherapy patients inceresed,too.Conclusion Puerarin could attenuate radiation-induced injury of vascular endothelial cells via targeted regulation of PLGF by miR-34 a.