Repetitive ischemia increases myocardial dimethylarginine dimethylaminohydrolase 1 expression. (June 2017)

• Record Type: Journal Article
• Authors: Zhang, Ping; Fassett, John T; Zhu, Guangshuo; Li, Jingxin; Hu, Xinli; Xu, Xin; Chen, Yingjie; Bache, Robert J
• Is Part Of: Vascular medicine. Volume 22:Number 3(2017)
• Page Start: 179
• Page End: 188
• Publication Date: 2017-06
• Subjects: asymmetric dimethylarginine (ADMA) -- IL-1β -- nitric oxide synthase -- protein arginine methyl transferase -- TNF-α; Blood-vessels -- Diseases -- Periodicals; Peripheral vascular diseases -- Periodicals; Vascular Diseases -- Periodicals; Vaisseaux sanguins -- Maladies -- Périodiques; Maladies vasculaires périphériques -- Périodiques; 616.13
• DOI: 10.1177/1358863X16681215
• Languages: English
• ISSNs: 1358-863X

Abstract

Pharmacologic inhibition of nitric oxide production inhibits growth of coronary collateral vessels. Dimethylarginine dimethylaminohydrolase 1 (DDAH1) is the major enzyme that degrades asymmetric dimethylarginine (ADMA), a potent inhibitor of nitric oxide synthase. Here we examined regulation of the ADMA-DDAH1 pathway in a canine model of recurrent myocardial ischemia during the time when coronary collateral growth is known to occur. Under basal conditions, DDAH1 expression was non-uniform across the left ventricular (LV) wall, with expression strongest in the subepicardium. In response to ischemia, DDAH1 expression was up-regulated in the midmyocardium of the ischemic zone, and this was associated with a significant reduction in myocardial interstitial fluid (MIF) ADMA. The decrease in MIF ADMA during ischemia was likely due to increased DDAH1 because myocardial protein arginine N -methyl transferase 1 (PRMT1) and the methylated arginine protein content (the source of ADMA) were unchanged or increased, respectively, at this time. The inflammatory mediators interleukin (IL-1β) and tumor necrosis factor (TNF-α) were also elevated in the midmyocardium where DDAH1 expression was increased. Both of these factors significantly up-regulated DDAH1 expression in cultured human coronary artery endothelial cells. Taken together, these results suggest that inflammatory factors expressed in response to myocardial ischemia contributed to up-regulation of DDAH1, which was responsible for the decrease in MIF ADMA.