氧化应激可通过NF-κB-iNOS-NO信号通路诱导小鼠胰岛β细胞凋亡  

OXIDATIVE STRESS INDUCES APOPTOSIS VIA NF-κB-iNOS-NITRIC OXIDE PATHWAY IN PANCREATIC β-CELLS

作　　者：王燕萍[1] 潘晓东[2] 姜苏原[3] 刘礼斌[1] 陈洲[4] 

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]福建医科大学附属协和医院,福建省老年医学研究所,福建福州350001 [3]上海瑞金医院内分泌研究所,上海200025 [4]福建医科大学药学院,福建福州350001

出　　处：《中国应用生理学杂志》2009年第2期255-259,共5页Chinese Journal of Applied Physiology

基　　金：福建省卫生厅青年基金(2006-1-7);福建省教育厅资助项目(JA03087)

摘　　要：目的:探讨第三丁基过氧化氢(t-BHP)诱导小鼠胰腺β细胞株MIN6细胞凋亡的可能机制。方法:体外培养小鼠β细胞株MIN6,AO-EB染色荧光显微镜观测细胞凋亡形态,Annexin-Ⅴ-PI染色流式细胞技术测定细胞凋亡率,Griess化学显色法检测细胞内一氧化氮(NO)水平,Western blot检测胞浆诱导型一氧化氮合酶(iNOS)蛋白、胞浆及胞核核因子-κB片断p65(NF-κB p65)蛋白表达水平。结果:25μmol/Lt-BHP处理60 min后可明显引起胰腺β细胞凋亡并引起细胞NO水平明显升高;该浓度的t-BHP处理30 min时胞浆iNOS蛋白达高峰水平;而该浓度的t-BHP处理20 min时胞核NF-κB活化片断p65蛋白达高峰水平;iNOS抑制剂L-NAME或抗氧化剂NAC可明显抑制β细胞凋亡及NO水平的增高。结论:t-BHP引起的氧化损伤可通过NF-κB-iNOS-NO途径诱导MIN6细胞凋亡。To explore the possible mechanism of tert-butyl hydroperoxide （t-BHP）-induced apoptosis in murine MIN6 pancreatic β-cells. Methods： MIN6 cells were cultured in vitro. Cell damage was evaluated by epifluorescence microscopy after staining with AO-EB. The percentage of cell apoptosis was determined by flow cytometric assay after Annexin- Ⅴ -PI staining. Nitric oxide levels were measured by Griess assay. Inducible nitric oxide synthase（iNOS） protein and NF-κBp65 fragment were detected by Western blot. Results： Exposure of 25 μmol/L t-BHP to MIN6 cells for 60 min, cell viability was reduced and the percentage of apoptosis was increased significantly. The levels of cytoplasmic iNOS protein and nitrite were elevated. Meanwhile, treatment with t-BHP resulted in nucleus NF-κBp65 fragment peaking at 20 min. Both L-NAME and N-Acetyl-l-cysteine （NAC） attenuated the elevated levels of nitrite and percentage of apoptosis due to t-BHP alone. Conclusion： NF-κB-iNOS-nitric oxide signalling pathway can mediated t-BHP induced apoptosis in MIN6 cells .

关 键 词：胰腺Β细胞 凋亡 氧化损伤 核因子ΚB 诱导型一氧化氮合酶 一氧化氮 

分 类 号：R587[医药卫生—内分泌]