Dimethylarginine dimethylaminohydrolase 1 modulates endothelial cell growth through nitric oxide and Akt.
Dimethylarginine dimethylaminohydrolase 1 modulates endothelial cell growth through nitric oxide and Akt.
复制标题
DOI：
10.1161/atvbaha.110.215640
复制
发表时间：
2011-04
期刊：
影响因子：
--
通讯作者：
Bache RJ
中科院分区：
文献类型：
--
作者：
Zhang P;Hu X;Xu X;Chen Y;Bache RJ
二甲基精氨酸二甲氨基水解酶1通过降解内源性一氧化氮合酶抑制剂ADMA和L-NMMA来调节NO的产生。这项研究考察了DDAH1除了降解ADMA外，是否还发挥ADMA独立作用，从而影响内皮功能。通过用小干扰RNA选择性沉默DDAH1和在HUVEC中过表达DDAH1，我们发现DDAH1通过Akt磷酸化和通过降解ADMA的传统作用促进内皮细胞的增殖、迁移和管状形成。一氧化氮合酶抑制剂L-NAME或阿霉胺、鸟苷酸环化酶抑制剂ODQ或cGMP类似物8-PCPT-cGMP共同孵育人脐静脉内皮细胞对p-AktSer473无影响，提示DDAH1增加p-AktSer473的产生不依赖于NO-cGMP信号通路。DDAH1与RAS形成蛋白质复合体，过表达DDAH1可增强RAS活性。RAS抑制剂manumycin-A或显性负性RAS显著减弱DDAH1诱导的p-AktSer473的增加。此外，DDAH1基因敲除损伤了培养的主动脉环内皮细胞的萌发，而过表达固有活性的Akt或DDAH1则挽救了这些小鼠主动脉环内皮细胞的萌发。DDAH1在激活Akt方面发挥着独特的作用，该作用不依赖于降解内源性NOS抑制剂而影响内皮功能。
Dimethylarginine dimethylaminohydrolase 1 (DDAH1) modulates NO production by degrading the endogenous NO synthase (NOS) inhibitors ADMA and L-NMMA. This study examined whether, in addition to degrading ADMA, DDAH1 exerts ADMA independent effects that influence endothelial function. Using selective gene silencing of DDAH1 with small interfering RNA and overexpression of DDAH1 in HUVEC, we found that DDAH1 acts to promote endothelial cell proliferation, migration and tube formation both by Akt phosphorylation as well as through the traditional role of degrading ADMA. Incubation of HUVEC with the NOS inhibitors L-NAME or ADMA, the soluble guanylyl cyclase inhibitor ODQ, or the cGMP analog 8-pCPT-cGMP had no effect on p-AktSer473, indicating that the increase of p-AktSer473 produced by DDAH1 was independent of the NO-cGMP signaling pathway. DDAH1 formed a protein complex with Ras, and DDAH1 overexpression increased Ras activity. The Ras inhibitor manumycin-A or dominant-negative Ras significantly attenuated the DDAH1-induced increase of p-AktSer473. Furthermore, DDAH1 knockout impaired endothelial sprouting from cultured aortic rings, and overexpression of constitutively active Akt or DDAH1 rescued endothelial sprouting in the aortic rings from these mice. DDAH1 exerts a unique role in activating Akt that affects endothelial function independent of degrading endogenous NOS inhibitors.