摘要
目的探讨重组血管紧张素转换酶2(ACE2)基因转染对内皮源性一氧化氮(NO)合酶(eNOS)磷酸化水平的影响。方法克隆和构建含人ACE2基因全长的重组质粒(pACE2),并将之转染入人血管内皮细胞中;采用实时定量PCR和Western印迹技术检测转染细胞中的ACE2、eNOS的表达情况,同时使用硝酸还原酶比色法测定细胞中NO含量。结果血管紧张素II(AngII,100nmol/L)加入细胞后可抑制由胰岛素刺激的Ser1177-eNOS磷酸化与NO生成(n=5～6,P<0.01)。pACE2基因转染可逆转细胞中由AngII对胰岛素诱导eNOS磷酸化的抑制效应,同时伴NO水平上升(n=5～6,P<0.01)。结论ACE2过表达可明显改善人血管内皮细胞中eNOS磷酸化的表达,伴有NO生成增加,提示ACE2可能通过调节血管AngII/NO的平衡,在改善血管内皮功能和胰岛素抵抗中起重要功效。
Objective To investigate the effects of recombinant angiotensin-converting enzyme 2 （ACE2） gene transfer on the phosphorylation levels of endothelial nitric oxide （NO） synthase （eNOS）. Methods A recombinant plasmid encompassing human ACE2 gene （pACE2） was constructed and transfected into these human vascular endothelial cells. The expression levels of ACE2, eNOS in endothelial cells were determined with real-time PCR and Western blotting. NO contents were measured with nitrate reductase colorimetric method in cells. Results Treatment with angiotensin Ⅱ （Ang Ⅱ, 100 nmol/L） diminished insulin-stimulated Ser^1177- eNOS phosphorylation activation and NO generation （ n = 5 - 6, P 〈 0.05, respectively） , which were strikingly reversed by pACE2 gene transfer in endothelial cells （ n = 5 - 6, P 〈 0.05, respectively）. Conclusion ACE2 gene over-expression contributes to improvement of eNOS phosphorylation expression and enhancement of NO in endothelial cells. It is suggested that ACE2 genc may have an important potential property to improve vascular endothelial function and insulin resistance through modulating the balance between Ang Ⅱ and NO levels.
出处
《航天医学与医学工程》
CAS
CSCD
北大核心
2009年第3期172-175,共4页
Space Medicine & Medical Engineering
基金
国家自然科学基金(30700328)
广东省自然科学基金(7300041)
宁波市自然科学基金(2008A610077)
