Endothelial dysfunction during acute methionine load in hyperhomocysteinaemic patients

Hyperhomocysteinaemia has been addociated with arterial and verous thrombosis possibly by causing damage to the endothelium, We hypothesized that an oral load in methionine, that increases plasma homocysteine, would also result in an increase in biological markers of endothelial or platelet dysfunction. Then we investigated 2 groups of patients with arterial or venous occlusive disease: 17 with hyperhomocysteinemia and 12 withour hyperhomocysteinemia. We measured in both groups plasma soluble thrombomodulin, von Willebrand factor, P-selectin and tissue factor plasma inhibitor before and 6 hours after a load with 100 mg/kg oral methionine. Methionine load resulted in a significant increase in von Willebrand factor in both groups (p < 0.02), suggesting that endothelial dysfunction occurs during the load.