中文摘要：

目的：研究阿魏酸对电离辐射所致人脐静脉血管内皮细胞(HUVEC)损伤的保护作用，及其对辐射敏感蛋白Thbd和γH2AX的影响，探讨阿魏酸的抗辐射作用与机制。方法：以4~16Gy的Co射线照射HUVEC细胞，照后48h以MTS法检测细胞活力，探索适宜照射剂量。以10Gyγ射线照射HUVEC细胞，分别于照射后1、3、6、12、24和48h提取细胞总蛋白，蛋白质印迹法检测蛋白Thbd和γH2AX的表达水平。并于照射前2h，预防性给予细胞0.001~1μmol/L的阿魏酸，照后48h检测细胞活力、Thbd和γH2AX蛋白表达水平的改变。结果：与未照射组(0Gy)比较，HUVEC受到10Gyγ照射后48h，细胞活力约降低30%(<0.05)。以此剂量照射，照后1hThbd约降至正常水平的0.6(P<0.05)，照射后48hγH2AX约升高至正常水平的5倍(P<0.05)。与照射对照组比较，0.1和1μmol/L的阿魏酸作用后，受照HUVEC的细胞活力提高(P<0.05)，Thbd蛋白表达升高(P<0.05)，γH2AX蛋白表达降低(P<0.05)。结论：0.1~1μmol/L的阿魏酸可调节10Gyγ射线照射后HUVEC的Thbd和γH2AX蛋白的表达水平，从而促进HUVEC增殖，提高其细胞活力，发挥抗辐射作用。

英文摘要：

OBJECTIVE:To study the effect of ferulic acid on damage of human umbilical vein endothelial cells60(HUVECs)from their exposure to ionizing radiation METHODS:HUVECs were exposed to Co gamma ray at theradiation doses of4-16Gy.Cells viability as determined by the MTS assay was examined48h after irradiation to select theappropriate irradiation dose.Expression levels of Thbd andγH2AX were examined by western blot assay with the totalprotein of HUVEC extracted at1,3,6,12,24and48h after irradiation.In addition,HUVEC received0.001-1μmol/L ferulic acid at2h before irradiation.Cell viability and expression of Thbd andγH2AX protein were determined at48hours after irradiation.RESULTS:Compared with the non-irradiated group,cell viability at48h after10Gyirradiation was decreased by30%(P<0.05).Thbd expression was reduced to about0.6-fold(P<0.05)at1h after irradiation.γH2AX was increased about5times(P<0.05)at48h after irradiation.Addition of0.1to1μmol/L ferulic acid increased theviability of irradiated HUVEC and the protein expression of Thbd at1h after irradiation,and decreased the expression ofγH2AX at48h after irradiation.CONCLUSION:Ferulic acid in the concentration of0.1-1μmol/L played a role inradiation protection since it promoted cell vitality and proliferation by increasing the expression of Thbd protein anddecreasing the expression ofγH2AX protein.