Antioxidative vitamins and oxidative lipid and DNA damage in relation to nutrition

Abstract

Marica Krajcovicova-Kudlackova, Martina Valachovicova, Csilla Mislanova, Jana Pribojova

Nutrition is a key environmental factor influencing the incidence of chronic age related free radical induced diseases. The better antioxidant status by a sufficient consumption of food commodities with antioxidant compounds helps to minimize oxidative damage, and thus can delay or prevent pathological changes. In three groups of adult apparently healthy non-smoking population of different nutritional habits (93 persons of general population, non-vegetarians, NV; 77 semi-vegetarians, V-S; 64 lacto-ovo-vegetarians, V-LO) plasma concentrations of vitamins B9, C, E and β-carotene, potential prooxidant homocysteine and products of oxidative damage of lipids (total peroxides, malondialdehyde, oxidized LDL) as well as and oxidative DNA damage in lymphocytes (strand breaks, oxidized purines, oxidized pyrimidines) were measured. Vegetarian (V-S, V-LO) vs NV plasma concentrations of vitamin C, vitamin E, lipid standardized vitamin E, β-carotene and vitamin B9 were significantly higher. Plasma total homocysteine values are significantly higher in both vegetarian groups as a consequence of deficient vitamin B12 concentrations. Hyperhomocysteinemia, a marker of systemic or endothelial oxidative stress may promote the production of hydroxyl radicals which are the initiators of lipid oxidation. In spite of 28.5% and 40.6% incidence of hyperhomocysteinemia in V-S and V-LO, the concentrations of total peroxides, malondialdehyde as well as values of oxidized LDL were significantly reduced as a consequence of a better antioxidant status. Parameters of DNA damage as biomarkers of cancer risk in epidemiological studies are significantly reduced in two groups of vegetarians. The findings suggest that dominant consumption of plant food in vegetarians, higher intake of dietary antioxidants and their higher plasma concentrations in comparison to general population may have protective effects against oxidative damage of molecules and a preventive effect on incidence of chronic age related diseases.