Methionine cycle kinetics and arginine supplementation in endothelial dysfunction of ESRD.

Abstract

To investigate the effect of arginine supplementation on metabolic pathways involved in endothelial dysfunction of end stage renal disease (ESRD), we conducted a study on 11 ESRD patients age 49±16; wt 93±26 kg receiving an adequate protein and energy intake for 1week, followed by a primed, continuous, 9h infusion (4h fast;5h fed) of L-[1-13C] methionine, L-[2H3] methyl methionine, and determination of flow mediated vasodilatation (FMD). After a break period, they received daily arginine supplementation of 21g, for 4weeks, and the studies were repeated. Diets were isonitrogenous. The rates of methionine transmethylation (TM), Transulfuration (TS) and Remethylation RM are shown in Table 1. There was an effect of the metabolic period, fast vs. fed on remethylation rates for the arginine supplemented diet, and on the TS rates for the control and arginine supplemented periods. However, there was no effect of arginine supplementation on the rates of TM, TS, RM or on FMD. Arginine supplementation does not affect methionine cycle metabolism. NIH DK62363, Ajinomoto 3ARP Program. Table 1. Methionine cycle kinetics during control diet and arginine supplementation.