Carbon monoxide and nitric oxide mediate cytoskeletal reorganization in microvascular cells via vasodilator-stimulated phosphoprotein phosphorylation - Evidence for blunted responsiveness in diabetes
Carbon monoxide and nitric oxide mediate cytoskeletal reorganization in microvascular cells via vasodilator-stimulated phosphoprotein phosphorylation - Evidence for blunted responsiveness in diabetes
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DOI：
10.2337/db08-0381
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发表时间：
2008-09-01
期刊：
影响因子：
7.7
通讯作者：
Grant, Maria B.
中科院分区：
文献类型：
--
作者：
Calzi, Sergio Li;Purich, Daniel L.;Grant, Maria B.
目的：我们研究了血管活性物质一氧化碳(CO)和一氧化氮(NO)对血管扩张剂刺激的磷酸蛋白(VASP)磷酸化和细胞内再分布的影响。VASP是细胞迁移所需的一种关键的肌动蛋白，也控制着血管扩张和血小板聚集。研究设计和方法-我们检测了供体释放的CO和NO在非糖尿病和糖尿病患者内皮祖细胞(EPC)和血小板以及在低糖(5.5 mmol/L)和高糖(25 mmol/L)条件下培养的人微血管内皮细胞(HMECs)中的作用。结果在对照血小板中，CO选择性地促进Vasp Ser-157的磷酸化，而NO主要促进Ser-157和Ser-239的磷酸化，两种药物对Ser-157和Ser-239的作用分别在1min和15min达到最大。在糖尿病患者的血小板中，两种药物都没有导致Vasp的磷酸化。在非糖尿病内皮祖细胞中，NO和CO分别增加Ser-239和Ser-157的磷酸化，但在糖尿病内皮祖细胞中这一反应显著降低。在低糖培养的内皮细胞中，CO和NO均诱导Ser-157和Ser-239的磷酸化，而在高糖培养的内皮细胞中，这种反应完全消失。在对照组内皮细胞和暴露于低糖的HMECs中，在CO或NO暴露后，Vasp被重新分布到丝状结构；然而，在高糖条件下，这种重新分布显著减弱。结论血管活性气体CO和NO通过特定部位和细胞类型的Vasp磷酸化促进细胞骨架的变化，在糖尿病患者，对这些药物的钝化反应可能导致血管修复和组织灌流减少。
OBJECTIVE-We examined the effect of the vasoactive agents carbon monoxide (CO) and nitric oxide (NO) on the phosphorylation and intracellular redistribution of vasodilator-stimulated phosphoprotein (VASP), a critical actin motor protein required for cell migration that also controls vasodilation and platelet aggregation.RESEARCH DESIGN AND METHODS-We examined the effect of donor-released CO and NO in endothelial progenitor cells (EPCs) and platelets from nondiabetic and diabetic subjects and in human microvascular endothelial cells (HMECs) cultured tinder low (5.5 mmol/l) or high (25 mmol/l) glucose conditions. VASP phosphorylation was evaluated using phosphorylation site-specific antibodies.RESULTS-In control platelets, CO selectively promotes phosphorylation at VASP Ser-157, whereas NO promotes phosphorylation primarily at Ser-157 and also at Ser-239, with maximal responses at 1 min with both agents on Ser-157 and at 15 min on Ser-239 with NO treatment. In diabetic platelets, neither agent resulted in VASP phosphorylation. In nondiabetic EPCs, NO and CO increased phosphorylation at Ser-239 and Ser-157, respectively, but this response was markedly reduced in diabetic EPCs. In endothelial cells cultured under low glucose conditions, both CO and NO induced phosphorylation at Ser-157 and Ser-239; however, this response was completely lost when cells were cultured under high glucose conditions. In control EPCs and in HMECs exposed to low glucose, VASP was redistributed to filopodia-like structures following CO or NO exposure; however, redistribution was dramatically attenuated under high glucose conditions.CONCLUSIONS-Vasoactive gases CO and NO promote cytoskeletal changes through site- and cell type-specific VASP phosphorylation, and in diabetes, blunted responses to these agents may lead to reduced vascular repair and tissue perfusion.