Rosiglitazone reduces glucose-induced oxidative stress mediated by NAD(P)H oxidase via AMPK-dependent mechanism
Rosiglitazone reduces glucose-induced oxidative stress mediated by NAD(P)H oxidase via AMPK-dependent mechanism
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DOI：
10.1161/atvbaha.107.155762
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发表时间：
2007-12-01
影响因子：
8.7
通讯作者：
Avogaro, Angelo
中科院分区：
文献类型：
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作者：
Ceolotto, Giulio;Gallo, Alessandra;Avogaro, Angelo
目的 - 高血糖是长期糖尿病并发症的主要决定因素，主要通过诱导氧化应激来实现。NAD（P）H氧化酶是葡萄糖诱导的氧化应激的主要来源。在本研究中，我们验证了罗格列酮（RSG）能够通过阻止NAD（P）H氧化酶的激活来抑制高血糖引发的氧化应激这一假设。
方法与结果 - 使用荧光探针TEMPO - 9 - AC测量暴露于对照（5 mmol/L）和中度高（10 mmol/L）葡萄糖浓度的人脐静脉内皮细胞（HUVECs）中的细胞内活性氧（ROS）。通过蛋白质印迹法测定NAD（P）H氧化酶和腺苷酸活化蛋白激酶（AMPK）的活性。我们发现，与5 mmol/L葡萄糖相比，10 mmol/L葡萄糖显著增加了ROS的产生，而RSG完全消除了这种效应。有趣的是，抑制AMPK而非过氧化物酶体增殖物激活受体γ（PPARγ）可阻止RSG的这种作用。RSG对AMPK的磷酸化作用对于其阻碍NAD（P）H氧化酶激活的能力是必需的，而NAD（P）H氧化酶的激活对于葡萄糖诱导的氧化应激是不可或缺的。在AMPK激活的下游，RSG通过抑制蛋白激酶C（PKC）发挥抗氧化作用。
结论 - 本研究表明，RSG激活AMPK，进而防止高血糖诱导的NAD（P）H氧化酶过度活跃，可能是通过抑制PKC实现的。因此，RSG以一种依赖AMPK且不依赖PPARγ的机制保护内皮细胞免受葡萄糖诱导的氧化应激。
Objective-Hyperglycemia is the main determinant of long-term diabetic complications, mainly through induction of oxidative stress. NAD(P)H oxidase is a major source of glucose-induced oxidative stress. In this study, we tested the hypothesis that rosiglitazone (RSG) is able to quench oxidative stress initiated by high glucose through prevention of NAD(P)H oxidase activation.Methods and Results-Intracellular ROS were measured using the fluoroprobe TEMPO-9-AC in HUVECs exposed to control (5 mmol/L) and moderately high (10 mmol/L) glucose concentrations. NAD(P)H oxidase and AMPK activities were determined by Western blot. We found that 10 mmol/L glucose increased significantly ROS production in comparison with 5 mmol/L glucose, and that this effect was completely abolished by RSG. Interestingly, inhibition of AMPK, but not PPAR gamma, prevented this effect of RSG. AMPK phosphorylation by RSG was necessary for its ability to hamper NAD(P)H oxidase activation, which was indispensable for glucose- induced oxidative stress. Downstream of AMPK activation, RSG exerts antioxidative effects by inhibiting PKC.Conclusions-This study demonstrates that RSG activates AMPK which, in turn, prevents hyperactivity of NAD(P)H oxidase induced by high glucose, possibly through PKC inhibition. Therefore, RSG protects endothelial cells against glucose-induced oxidative stress with an AMPK-dependent and a PPAR gamma-independent mechanism.