Effects of α-lipoic acid on the plasma levels of asymmetric dimethylarginine in diabetic end-stage renal disease patients on hemodialysis:: A pilot study

Background/Aim: Endothelial dysfunction due to reduced nitric oxide (NO) availability precedes the development of atherosclerosis. Asymmetric dimethylarginine (ADMA), an endogenous inhibitor of NO synthase, is not only a cause of endothelial dysfunction, but also a predictor of the cardiovascular outcome in end-stage renal disease (ESRD) patients on hemodialysis (HD). alpha-Lipoic acid (ALA), a strong antioxidant, increases NO-mediated vasodilation in diabetic patients. We investigated whether ALA could decrease the plasma level of ADMA in diabetic ESRD patients on HD. Methods: Fifty patients undergoing HD three times per week were randomized to a treatment group receiving ALA 600 mg/day for 12 weeks or a control group. We measured the plasma levels of cholesterol, albumin, high-sensitivity C-reactive protein, oxidized low-density lipoprotein, hemoglobin A(1c), and ADMA in both groups at baseline and at 12 weeks. Results: In the control group, the levels of total cholesterol, serum albumin, high-sensitivity C-reactive protein, oxidized low-density lipoprotein, hemoglobin A(1c), and ADMA did not change. In the treatment group, the plasma levels of ADMA decreased significantly from a median of 1.68 (range 0.45-3.78) mu M to a median of 1.31 (range 0.25-3.19) mu M (p = 0.001). Conclusion: Considering that ADMA is an independent risk factor for cardiovascular outcome in ESRD patients, ALA may have the potential of a beneficial effect in them, in part by decreasing the plasma level of ADMA. Copyright (c) 2007 S. Karger AG, Basel.