Serum Asymmetric Dimethylarginine Levels in Patients with Acute Rheumatic Fever: Inflammation and Endothelial Dysfunction

Abstract

Endothelial dysfunction is considered to be an important and early step in the initiation and progression of atherosclerosis. 1 Nitric oxide is produced by the metabolism of L -arginine via endothelial NO synthase (eNOS) to maintain appropriate endothelial function (i.e., intracellular messaging, anti-in-fl ammatory, antithrombotic, and antiapoptotic effects). 1 Serum asymmetric dimethylarginine (ADMA) is an endogenous analog of L -arginine. 2 Studies have found an association between elevated ADMA levels and endothelial dysfunction in humans, which may partly be related to eNOS uncoupling that results in increased eNOS-derived superoxide production in human vessels. 2 Serum ADMA levels have been associated with coronary atherosclerosis in patients with clinical risk factors as well as in healthy individuals. 3 – 5 Plasma levels of ADMA have been associated with mortality and a worsened clinical outcome in diabetic patients with estab-lished coronary atherosclerotic disease. 6 The relationship between serum ADMA levels and acute rheumatic fever (ARF) is not well de fi ned. ARF is a clinical state of heightened in fl ammation driven by an autoimmune reac-tion. Sert and collogues in the accompanying article “ Serum Asymmetric Dimethylarginine Levels in Patients with Acute Rheumatic Fever ” have reported the results of their case control study exploring the relationship between markers of in fl ammation (erythrocyte sedimentation rate [ESR], serum C-reactive protein [CRP] level, serum ADMA) and disease activity. 7 This study in an elegant way has demonstrated (although in a small sample) a statistical association