Hyperhomocysteinemia in healthy young men and elderly men with normal serum folate concentration is not associated with poor vascular reactivity or oxidative stress

Abstract

The mechanism by which homocysteine (Hcy) causes endothelial dysfunction is probably mediated by oxidative stress. The aim of this study was to evaluate the effect of oxidative stress on endothelial function in young and elderly hyperhomocysteinemic (HHcy) men. A total of 35 HHcy (Hcy > 15 μmol/L), young (n = 15; 20-40 y) and elderly men (n = 20; > 65 y) and 33 normohomocysteinemic (NHcy; controls) young (n = 14) and elderly (n = 19) men (Hcy < 13 μmol/L), without classic cardiovascular risk factors were recruited. Serum Hcy, folate, and vitamin B-12, whole-blood glutathione, plasma total antioxidants status, TBARS, and 8-F2α isoprostanes were determined. Noninvasive ultrasound measurements of endothelium-dependent (EDVR) and -independent dilatation (EIVR) were performed. EDVR, EIVR, and markers of oxidative stress did not differ among the groups. Folate concentrations were higher in elderly than in young men (P < 0.001), independent of Hcy concentrations. Vitamin B-12 concentrations w