Effect of arginine:lysine and glycine:methionine intake ratios on dyslipidemia and selected biomarkers implicated in cardiovascular disease: A study with hypercholesterolemic rats.

profile and selected cardiovascular disease markers, was studied, in rats maintained on a
hypercholesterolemic diet. The rise in blood cholesterol was countered by 32%, 24%, and 49%,
respectively, through increased oral supplementation of Arg, Gly, and Arg + Gly; a corresponding increase
in plasma phospholipids at the end of the 8-week study was observed. The elevated plasma cholesterol to
phospholipids ratio was countered by 27, 40, and 57%, respectively, through oral supplementation of Arg,
Gly, and Arg + Gly. The elevation in hepatic cholesterol was lowered by 18, 29, and 51%, respectively, while
phospholipids concentration was concomitantly increased by these amino acids. The elevated cholesterol
to phospholipids ratio was, thus, significantly countered in the hypercholesterolemic situation by orally
supplemented Arg, Gly, and Arg + Gly. Increased plasma asymmetric dimethylarginine (ADMA) levels,
under hypercholesterolemic conditions, were lowered by 12, 15 and 34%, respectively, while plasma
symmetric dimethylarginine (SDMA) levels were lowered by 14, 10 and 17%, respectively, with orally
supplemented Arg, Gly and Arg + Gly. Only Gly and Arg + Gly decreased plasma homocysteine levels. Total
nitric oxide (NO) concentration was considerably increased by Gly supplementation in hypercholester-
olemic rats. Thus, altered ratios of Arg:Lys or Gly:Met offered beneficial influence on the lipid profile and
plasma levels of ADMA, SDMA and homocysteine in hypercholesterolemic rats. Optimal beneficial
effects, among ratios tested, was observed when Arg:Lys and Gly:Met ratios were maintained in ratios of
1:1 and 2:1, respectively.