Damage of molecules as a consequence of oxidative stress has been implicated in the pathogenes is of chronic diseases related to aging. Diet is a key environmental factor affecting the incidence of many chronic diseases. Antioxidant substances in diet enhance the DNA, lipid and protein protection by increasing the scavenging of free radicals. Products of oxidative damage of DNA (DNA strand breaks with oxidized purines or oxidized pyrimidines), lipids (conjugated dienes of fatty acids) and proteins (carbonyls) in relation to nutrition (vegetarian diet vs. non-vegetarian, traditional mixed diet) were measured in young women aged 20-30 years (46 vegetarians, 48 non-vegetarians) vs. older women aged 60-70 years (33 vegetarians, 34 non-vegetarians). In young subjects, no differences in values of oxidative damage as well as plasma values of antioxidative vitamins (C, β-carotene) were observed between vegetarian and non-vegetarian groups. In older vegetarian group significantly reduced values of DNA breaks with oxidized purines, DNA breaks with oxidized pyrimidines and lipid peroxidation and on the other hand, significantly increased plasma values of vitamin C and β-carotene were found compared to the respective non-vegetarian group. Significant age dependences of measured parameters (increase in all oxidative damage products and decrease in plasma vitamin concentrations in older women) were noted only in non-vegetarians. Vegetarian values of older women vs. young women were similar or non-significantly changed. The results suggest that increase of oxidative damage in aging may be prevented by vegetarian nutrition., M. Krajčovičová-Kudláčková, M. Valachovičová, V. Pauková, M. Dušinská., and Obsahuje bibliografii a bibliografické odkazy
Levels of conjugated dienes of fatty acids (first peroxidation product) in relation to their substrates and promotors (triacylglycerols, homocysteine, iron) as well as to their inhibitors (essential antioxidative vitamins) were assessed in a vegetarian group (n=24) and compared with subjects on a mixed diet (traditional nutrition, n=24). Positive significant linear correlation between conjugated dienes and triacylglycerols, homocysteine, iron as well as inverse relationship between conjugated dienes and vitamin E, vitamin C, beta-carotene were observed in pooled groups. Lipid peroxidation risk in vegetarians seems to be caused predominantly by hyperhomocysteinemia, whereas in a mixed diet group this was due to a higher supply of substrates or risk iron values. The incidence of only 8 % of risk conjugated diene values in vegetarians in contrast to 42 % in the group with traditional diet indicates that vegetarians have a better antioxidative status as a consequence of regular consumption of protective food.