高糖对INS-1细胞线粒体呼吸链功能的影响  

High glucose impairs mitochondrial respiratory chain function in pancreatic β cells

作　　者：林占[1] 薛耀明[1] 沙建平[1] 毛睿睿[1] 龙可[1] 桑丹[1] 

机构地区：[1]南方医科大学南方医院内分泌代谢科,广东广州510515

出　　处：《南方医科大学学报》2009年第6期1251-1253,共3页Journal of Southern Medical University

摘　　要：目的探讨高糖对INS-1细胞线粒体呼吸链功能的影响。方法将INS-1细胞随机分为正常对照组(葡萄糖5.5mmol/L培养)、高糖组(葡萄糖16.7mmol/L培养)、N-乙酰半胱氨酸(N-acetyl-L-cysteine,NAC)+高糖组(NAC1.0mmol/L+葡萄糖16.7mmol/L培养),均干预72h。分光光度计测定呼吸链酶复合物Ⅰ、Ⅲ活性,荧光素酶方法检测细胞内ATP含量,放免法测定胰岛素分泌水平。结果高糖组的呼吸链酶复合物Ⅰ活性〔(1.53±0.24)μmol/(mg·min)〕、Ⅲ活性〔(1.08±0.22)μmol/(mg·min)〕分别较正常对照组的呼吸链酶复合物Ⅰ活性〔(2.31±0.33)μmol/(mg·min)〕、Ⅲ活性〔(1.92±0.39)μmol/(mg·min)〕下降,差异有统计学意义(P<0.01)。细胞ATP含量及胰岛素分泌水平在高糖组也较正常对照组明显减少(P<0.01)。使用抗氧化剂NAC干预高糖组,其线粒体酶复合物Ⅰ、Ⅲ活性、细胞ATP含量及胰岛素分泌水平均显著增加(P<0.05)。结论高糖损伤INS-1细胞的胰岛素分泌可能与损伤线粒体呼吸链功能有关,高糖可能通过氧化应激损伤INS-1细胞线粒体呼吸链功能。Objective To investigate the effect of high glucose on mitochondrial respiratory chain function in INS-1 cells. Methods The pancreatic β cell line INS-1 was divided into the normal control （NC）, high glucose （HG）, and N-acetyl-L-cysteine （NAC） pretreatment groups, which were cultured for 72 h in the presence of 5.5 mmol/L glucose, 16.7 mmol/L glucose, and 16.7 mmol/L glucose with 1.0 mmol/L NAC, respectively. The activities of the enzyme complexes I and III of the respiratory chain in the cells were assessed with spectrophotometry, the ATP levels were examined using a luciferinluciferase kit, and insulin levels detected by radioimmunoassay. Results The activities of the respiratory chain enzyme complexes Ⅰ and Ⅲ were 1.53±0.24 and 1.08±0.22 μmol .mg^-1 .min^-1 in high glucose group, respectively, significantly lower than those in the normal control group （2.31±0.33 and 1.92±0.39 μmol.mg^-1.min^-1, P〈0.01）. ATP and insulin levels also decreased significantly in high glucose group as compared with those in the normal control group （P〈0.01）. The addition of NAC partially inhibited high glucose-induced decreases in the enzyme complex activities, ATP levels and insulin secretion （P〈0.05）. Conclusion The respiratory chain function is positively correlated to insulin secretion in INS-1 cells, and exposure to high glucose causes impairment of the two enzyme complexes activities through oxidative stress, resulting in the mitochondrial respiratory chain dysfunction. High glucose-induced damages of the mitochondrial respiratory chain function can be partially inhibited by NAC.

关 键 词：高糖 呼吸链 酶复合物 Β细胞 N-乙酰半胱氨酸 

分 类 号：R587.1[医药卫生—内分泌]