外源性H2S增加Keap1硫巯基化水平延缓大鼠主动脉内皮细胞衰老的机制  

Exogenous H2S delays the aging of rat aortic endothelial cells by increasing the level of sulfur thiolated Keapl

作　　者：丁宁顶 乔伟丽 刘磊 崔洁 闫长栋 DING Ningding;LIU Lei;CUI Jie;QIAO Weili;YAN Changdong(Department of Physiology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China)

机构地区：[1]徐州医科大学生理学教研室,江苏徐州221004

出　　处：《徐州医科大学学报》2018年第1期1-4,共4页Journal of Xuzhou Medical University

基　　金：国家自然科学基金（81200250）;江苏省自然科学基金（BK20131119）

摘　　要：目的研究硫化氢（hydrogensulfide，H2S）延缓大鼠主动脉内皮细胞（RAECs）衰老的机制。方法细胞按不同处理方法分为6组：年轻组、老年组、DMSO组、NaHS组、ATRA组、NaHS＋ATRA组。用β-半乳糖苷酶（β-ga1）染色法检测内皮细胞的老化程度，用改良生物素法测定内皮细胞Keap1巯基蛋白，用免疫印迹法测定内皮细胞核转录因子（Nrf2）和超氧化物歧化酶2（SOD2）。结果与年轻组相比，老年组细胞β—ga1染色阳性数升高（P〈0．01）。给予外源性H2S（NariS）处理后，老年组细胞染色阳性数降低（P〈0．01）。预先给予Nrf2阻断剂全反式维甲酸（ATRA）后，老年组细胞染色阳性数升高（P〈0．01）。与老年组相比，NariS处理组内皮细胞Keap1硫巯基化水平、Nrf2和SOD2蛋白表达均升高（P〈0．01）；预先给予ATRA阻断Nrf2蛋白表达后，内皮细胞Nrf2及SOD2蛋白表达均明显降低（P〈0．01）。结论外源性H2S能通过提高内皮细胞Keap1的硫巯基化水平，减弱Keap1对Nrf2的抑制作用，促进Nrf2进入细胞核，从而增加其下游SOD2蛋白的表达，提高内皮细胞的抗氧化应激作用，延缓内皮细胞的衰老进程。Objective To investigate the mechanism by which hydrogen sulfide （ H2 S） delays the aging of rat aortic endothelial cells （RAECs）. Methods Cells were divided into six groups according to their corresponding treatment： a young group, an old group, a DMSO group, a NailS group, an ATRA group, and a NailS ＋ ATRA group. The aging of the cells was detected by β- galactosidase （ β - gal） staining. The level of thiolated Keapl was determined by a modified biotin method. The amounts of nuclear transcription factor Nrf2 and superoxide dismutase 2 （SOD2） were detected by Western blotting. Results Compared with the young group, the positive rate of β- gal staining was remarkably in- creased in the old group （ P 〈 0.01 ） , which was then reduced after treatment with exogenous H2 S （NariS） （ P 〈 0. 01 ）. Pre - treatment with Nrf2 blocker all traMs retinoic acid （ATRA） could result in decreases in the positive rate ofβ - gal staining in old group （P 〈 0.01 ）. Compared with the old group, the levels of sulfur thiolated Keapl, Nrf2, SOD2 were increased in NariS -treated endothelial cells （P 〈 0.01 ）. Pre -treatment with ATRA could result in remarkable decrea- ses in the amounts of Nrf2 and SOD2 in endothelial cells （P 〈 0.01 ）. Conclusions Exogenous H2 S increases the levels of sulfur thiolated Keapl in endothelial cell, weakens the inhibitory effect of Keapl on Nrf2, stimulate the entry of Nrf2 into the nucleus, so as to increase the expression of downstream SOD2 protein, enhance the antioxidative stress in endo- thelial cell, and delay the aging process of the cells .

关 键 词：硫化氢 衰老 巯基化 大鼠主动脉内皮细胞 

分 类 号：R331.32[医药卫生—人体生理学]