Cor Vasa 2003, 44(2):100-103
Homocysteine and lipid peroxidation
- 1 Ústav preventívnej a klinickej medicíny
- 2 Nemocnica Ministerstva obrany, Bratislava, Slovenská republika
Homocysteine may cause atherosclerosis by damaging the endothelium either directly or by altering oxidative status. In hyperhomocysteinemia, hydroxyl radical production through homocysteine autooxidation and thiolactone formation is promoted. Antioxidant vitamins may have an adjunctive role in preventing oxidative vascular injury by hyperhomocysteinemia. Levels of total plasma homocysteine, conjugated dienes of fatty acids, vitamins C and E as well as their relationships were assessed in a group of 105 adult vegetarians. The correlation between the levels of homocysteine and conjugated dienes (first lipid peroxidation product) was shown to be a significantly positive linear one. Since 40% of the vegetarian group had homocysteine values over 15 µmol/L (as a result of vitamin B12 deficiency), conjugated diene values over 2.4 µmol/L-considered a risk-were found in only 8% of probands. A role is played by the potent antioxidant effect of vegetarian diet; thus vegetarians have overthreshold plasma values of antioxidant vitamins (92% of vitamin C, 89% of vitamin E/cholesterol, effective protection against LDL oxidation; 100% of vitamin E/triglycerides, effective protection against peroxidation of polyunsaturated fatty acids; and 100% of vitamin C/vitamin E are over threshold). An inverse significant linear correlation between homocysteine and vitamin C levels was noted in the vegetarian group. The results document a significant positive association of hyperhomocysteinemia and lipid peroxidation. Despite the finding of high hyperhomocysteinemia in vegetarians, correct vegetarian diets may confer effective prevention-as a result of higher content of antioxidants and optimal composition of fats-against disease due to free radicals. Folic acid and vitamin B12 cause a homocysteine-lowering effect and vitamin C while other antioxidants remove free radicals formed from homocysteine.
Keywords: Conjugated dienes of fatty acids; Homocysteine; Vegetarians; Vitamin C
Published: February 1, 2003 Show citation