cysteinylglycine and Hypertension

We hypothesized that redox analysis could provide sensitive markers of the oxidative pathway associated to the presence of an increasing number of cardiovascular risk factors (RFs), independently of type. We classified 304 subjects without cardiovascular disease into 4 groups according to the total number of RFs (smoking, hypertension, hypercholesterolaemia, hyperhomocysteinaemia, diabetes, obesity, and their combination). Oxidative stress was evaluated by measuring plasma total and reduced homocysteine, cysteine (Cys), glutathione, cysteinylglycine, blood reduced glutathione, and malondialdehyde. Twenty-seven percent of subjects were in group 0 RF, 26% in 1 RF, 31% in 2 RF, and 16% in ≥ 3 RF. By multivariable ordinal regression analysis, plasma total Cys was associated to a higher number of RF (OR = 1.068; 95% CI = 1.027-1.110, P = 0.002). Total RF burden is associated with increased total Cys levels. These findings support a prooxidant effect of Cys in conjunction with RF burden, and shed light on the pathophysiologic role of redox state unbalance in preclinical atherosclerosis.

Topics: Adult; Analysis of Variance; Cardiovascular Diseases; Cysteine; Diabetes Complications; Dipeptides; Female; Glutathione; Humans; Hypercholesterolemia; Hyperhomocysteinemia; Hypertension; Logistic Models; Male; Malondialdehyde; Middle Aged; Obesity; Oxidation-Reduction; Oxidative Stress; Prospective Studies; Risk Assessment; Risk Factors; Smoking

It has been postulated that an accumulation of a sulfhydryl-containing amino acid, homocysteine in plasma may induce arteriosclerosis. In order to explore a possible contribution of homocysteine to the development of cerebral infarction in middle-aged and elderly patients, plasma sulfhydryl-containing amino acid profiles of 45 patients with cerebral infarction (CI) were compared with those of 45 normotensive and 45 hypertensive controls, and 20 patients with cerebral bleeding (CB), of similar ages and sex. The concentrations of both free and total homocysteine in plasma were highest in patients with CI among the 4 groups, while plasma free and total cysteinylglycine levels were similar. Although both free and total cysteine levels were also higher in patients with CI than in normotensive controls, the total homocysteine/total cysteine ratio was highest in patients with CI among the four groups. The hypertensive controls had higher plasma free and total concentrations than normotensive controls, but the levels did not differ between the 21 normotensive and 24 hypertensive CI patients. Our results suggest that high levels of plasma homocysteine in conjunction with hypertension could be one of the risk factors for arteriosclerotic CI.

Topics: Adult; Aged; Cerebral Hemorrhage; Cerebral Infarction; Creatinine; Cysteine; Dipeptides; Female; Homocysteine; Humans; Hypertension; Male; Middle Aged; Uric Acid