Association of NAD(P)H Oxidase with Glucose-Induced Insulin Secretion by Pancreatic β-Cells
Association of NAD(P)H Oxidase with Glucose-Induced Insulin Secretion by Pancreatic β-Cells
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DOI：
10.1210/en.2008-1149
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发表时间：
2009-05-01
期刊：
影响因子：
4.8
通讯作者：
Carpinelli, A. R.
中科院分区：
文献类型：
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作者：
Morgan, D.;Rebelato, E.;Carpinelli, A. R.
我们先前描述了胰腺β细胞中存在烟酰胺腺嘌呤二核苷酸磷酸还原型[NAD（P）H]氧化酶组分及其被葡萄糖、棕榈酸和促炎细胞因子激活。在本研究中，研究了NAD（P）H氧化酶复合物对胰腺β细胞功能的重要性。将大鼠胰岛在葡萄糖和NAD（P）H氧化酶抑制剂二苯基碘鎓（diphenyleneiodonium）存在下孵育1h，或在p47反义寡核苷酸（PHOX）存在下孵育24 h。活性氧（ROS）的产生通过使用2，7-二氯二氢荧光素二乙酸酯的荧光测定来确定。检测胰岛素分泌、细胞内钙反应、[U-C-14]葡萄糖氧化以及葡萄糖转运蛋白-2、葡萄糖激酶和胰岛素基因的表达。反义寡核苷酸降低了p47（PHOX）表达[一种重要的NAD（P）H氧化酶胞质亚基]，与二苯碘鎓类似，也减弱了酶活性，如ROS产生减少所示。抑制NAD（P）H氧化酶活性对离体胰岛细胞内钙对葡萄糖的反应和葡萄糖刺激的胰岛素分泌具有抑制作用。NAD（P）H氧化酶抑制也减少葡萄糖氧化和葡萄糖转运蛋白2和葡萄糖激酶的基因表达。这些发现表明，NAD（P）H氧化酶活化在葡萄糖刺激的胰岛素分泌期间胰腺β细胞产生ROS中起重要作用。还显示了这种酶复合物对β细胞代谢的重要性和参与胰岛素分泌的机制。（内分泌学150：2197-2201，2009）
We previously described the presence of nicotinamide adenine dinucleotide phosphate reduced form [NAD(P)H] oxidase components in pancreatic beta-cells and its activation by glucose, palmitic acid, and proinflammatory cytokines. In the present study, the importance of the NAD(P)H oxidase complex for pancreatic beta-cell function was examined. Rat pancreatic islets were incubated in the presence of glucose plus diphenyleneiodonium, a NAD(P)H oxidase inhibitor, for 1 h or with the antisense oligonucleotide for p47(PHOX) during 24 h. Reactive oxygen species (ROS) production was determined by a fluorescence assay using 2,7-dichlorodihydrofluorescein diacetate. Insulin secretion, intracellular calcium responses, [U-C-14] glucose oxidation, and expression of glucose transporter-2, glucokinase and insulin genes were examined. Antisense oligonucleotide reduced p47(PHOX) expression [an important NAD(P)H oxidase cytosolic subunit] and similarly to diphenyleneiodonium also blunted the enzyme activity as indicated by reduction of ROS production. Suppression of NAD(P)H oxidase activity had an inhibitory effect on intracellular calcium responses to glucose and glucose-stimulated insulin secretion by isolated islets. NAD(P)H oxidase inhibition also reduced glucose oxidation and gene expression of glucose transporter-2 and glucokinase. These findings indicate that NAD(P)H oxidase activation plays an important role for ROS production by pancreatic beta-cells during glucose-stimulated insulin secretion. The importance of this enzyme complex for the beta-cell metabolism and the machinery involved in insulin secretion were also shown. (Endocrinology 150: 2197-2201, 2009)