Exendin-4体外通过抑制NF-κB-iNOS-NO信号减轻氧化应激诱导的小鼠MIN6胰岛β细胞凋亡  

Exendin-4 protected murine MIN6 pancreatic β-cells from oxidative stress-induced apoptosis via down-regulation of NF-κB-iNOS-NO pathway

作　　者：刘礼斌[1] 王燕萍[1] 潘晓东[1] 姜苏原[2] 陈洲[3] 

机构地区：[1]福建医科大学附属协和医院、福建省内分泌研究所,福建福州350001 [2]上海交通大学附属瑞金医院上海市内分泌研究所上海市内分泌肿瘤重点实验室,上海200025 [3]福建医科大学药学院,福建福州350004

出　　处：《药学学报》2008年第7期690-694,共5页Acta Pharmaceutica Sinica

基　　金：福建省高等学校新世纪优秀人才支持计划资助(NCETFJ-0703).

摘　　要：探讨胰高血糖素样肽-1受体激动剂Exendin-4(Ex-4)在氧化损伤诱导胰岛β细胞凋亡中的保护作用。培养的MIN6胰岛β细胞,通过AO-EB染色观察细胞凋亡形态,Annexin-V-PI染色流式技术测定凋亡率,Griess法检测细胞内一氧化氮水平,Western blotting检测胞浆iNOS蛋白、胞浆及胞核核因子-κBp65(NF-κBp65)蛋白表达水平。Ex-4可抑制叔丁基过氧化氢(t-BHP)诱导的β细胞凋亡,Ex-4(100 nmol.L-1)预处理较单独t-BHP处理,其凋亡率减少约67%(P<0.001)。Ex-4同时减少NO水平的增高,并抑制t-BHP诱导的β细胞NF-κBp65活化及iNOS蛋白表达水平。Ex-4可能通过抑制细胞内NF-κB活化、胞浆iNOS表达来抑制NO水平,最终减轻氧化损伤诱导的β细胞凋亡。To explore the effect of glucagon-like peptide-1 receptor agonist -Exendin4 （Ex--4）on murine MIN6 pancreatic β-cells apoptosis induced by oxidative stress, the morphological changes of cell damage were evaluated by epifluorescence microscopy after staining with AO-EB. The percentage of cell apoptosis was determined by flow cytometric assay after Annexin-V-FITC-PI staining. Nitric oxide level was measured by Griess reagent assay. Inducible nitric oxide synthase （iNOS） protein and NF-κBp65 fragment were detected by Western blotting. Ex4 inhibited the increase of nitrite level and percentage of apoptosis induced by t-BHP in MIN6 cells. Furthermore, Ex-4 partly reduced the expression of iNOS protein and the ratio of NF-κBp65 protein in nucleus：cytosol induced by t-BHP. These results suggest that Ex-4 protects MIN6 pancreatic β-cells from oxidative stress-induced apoptosis via down-regulation of NF-κB-iNOS-nitric oxide pathway.

关 键 词：EXENDIN-4 胰岛Β细胞 细胞凋亡 核因子κB 诱导型一氧化氮合酶 一氧化氮 叔丁基过氧化氢 

分 类 号：R742.5[医药卫生—神经病学与精神病学]