硫酸镁对人脐静脉血管内皮细胞照射后NF-κB/ICAM-1的影响

为研究硫酸镁对粘附蛋白ICAM-1及其调控基因NF-κB表达的影响,进而探讨硫酸镁对人脐静脉血管内皮细胞(human umbilical vein endothelial,HUVEC)放射损伤的防护机制。取对数生长期细胞分为空白对照组、单纯照射组、照射加药组,单次4 Gy X射线照射单纯照射组及照射加药组,其中照射加药组于照射前0.5 h加入1.25 mg／mL硫酸镁,收集样本,利用流式细胞术和RT-PCR法检测NF-κB、ICAM-1 mRNA的表达情况,Western blot、激光共聚焦检测NF-κB、ICAM-1蛋白的表达情况。结果表明,照射后72 h内,NF-κB、ICAM-1 mRNA表达均高于空白对照组,其中照后3 h表达最为显著;在照射后48、72 h,1.25 mg/mL硫酸镁处理组中NF-κB / ICAM-1蛋白均低于单纯照射组。以上结果说明,电离辐射能够诱导NF-κB /ICAM-1高表达,而硫酸镁能抑制其表达,且可能是通过抑制NF-κB核转位来调控ICAM-1表达的途径参与辐射损伤防护。

The influence of MgSO4 on the NF-κB/ICAM-1 of human umbilical vein endothelial cells after irradiation

To study the effect of magnesium sulfate on the expression of NF - κ B and ICAM-1, and to explore the protective mechanism of magnesium sulfate on radiation injury of HUVECs. The cells under exponential growth phase were divided into control group, irradiation group and irradiation+MgSO₄ group, and treated with a single 4 Gy X-ray except the control group, while 1.25 mg/mL was added to the irradiation+MgSO₄ group 0.5 h before the irradiation. Flow cytometry analysis and RT-PCR were used to study the expression of NF-κB/ICAM-1 mRNA, and NF-κB/ICAM-1 protein expression was detected by Western blot and the laser confocal microscope. The results showed that within 72 hours after irradiation, the expression levels of NF-κB、ICAM-1 mRNA were higher than that of control group, especially for 3 h;48 h and 72 h post-irradiation. The protein level of NF-κB/ ICAM-1 Proteins expression in the group of treated by 1.25 mg/mL MgSO₄ was significantly lower than that of the controls. These results indicate that ionizing radiation can induce the over expression of NF-κB/ICAM-1, and MgSO₄ down-regulation the expression of ICAM-1 by inhibited the trans-location of NF-κB, which may be the mechanisms of radiation protection.