Pancreatic β-cells express phagocyte-like NAD(P)H oxidase
Pancreatic β-cells express phagocyte-like NAD(P)H oxidase
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DOI：
10.2337/diabetes.52.6.1457
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发表时间：
2003-06-01
期刊：
影响因子：
7.7
通讯作者：
Carpinelli, AR
中科院分区：
文献类型：
--
作者：
Oliveira, HR;Verlengia, R;Carpinelli, AR
研究了胰腺β细胞中吞噬细胞样NAD(P)H氧化酶的存在。RT-PCR在胰岛中检测到3种NAD(P)H氧化酶组分：gp91（PHOX）、p22（PHOX）和p47（PHOX）。Western blotting检测到p67（PHOX）和p47（PHOX）。通过免疫组化，p47（PHOX）主要存在于胰岛的中心区域，证实了该成分在胰岛素生成细胞中的表达。免疫组织化学也检测了β细胞中NAD(P)H氧化酶复合物的激活：胰岛的超氧化物产生动力学比HIT-T15细胞、中性粒细胞和巨噬细胞慢，但在孵育2小时后，它们达到中性粒细胞硝基蓝四氮唑（NBT）还原的66%。与对照组相比，葡萄糖（5.6 mmol/l）使NBT减少率提高了75%。蛋白激酶C （PKC）参与葡萄糖的刺激作用被胰岛用肉豆酸酯（PKC激活剂）和bysindoylmale亚胺（GF109203X） （PKC特异性抑制剂）孵养证实：二苯碘[一种NAD(P)H氧化酶抑制剂]消除了葡萄糖诱导的NBT还原的增加，证实了胰岛中NAD(P)H氧化酶的活性。由于活性氧参与细胞内信号传导，葡萄糖激活吞噬细胞样NAD(P)H氧化酶可能在β细胞功能中起重要作用。
The presence of a phagocyte-like NAD(P)H oxidase in pancreatic beta-cells was investigated. Three NAD(P)H oxidase components were found in pancreatic islets by RT-PCR: gp91(PHOX), p22(PHOX) and p47(PHOX). The components p67(PHOX) and p47(PHOX) were also demonstrated by Western blotting. Through immunohistochemistry, p47(PHOX) was mainly found in the central area of the islet, confirming the expression of this component by insulin-producing cells. Activation of NAD(P)H oxidase complex in the beta-cells was also examined by immunohistochemistry: The pancreatic islets presented slower kinetics of superoxide production than HIT-T15 cells, neutrophils, and macrophages, but they reached 66% that of the neutrophil nitroblue, tetrazolium (NBT) reduction after 2 h of incubation. Glucose (5.6 mmol/l) increased NBT reduction by 75% when compared with control. The involvement of protein kinase C (PKC) in the stimulatory effect of glucose was confirmed by incubation of islets with phorbol myristate acetate (a PKC activator) and bysindoylmaleimide (GF109203X) (a PKC-specific inhibitor): Diphenylene iodonium [an NAD(P)H oxidase inhibitor] abolished the increase of NBT reduction induced by glucose, confirming the NAD(P)H oxidase activity in pancreatic islets. Because reactive oxygen species are involved in intracellular signaling, the phagocyte-like NAD(P)H oxidase activation by glucose may play an important role for beta-cell functioning.