Adequate intakes of vitamin E and protein prevent increases of oxidative damage to DNA, lipids, and protein induced by total body irradiation in mice.
We examined the influence of the level of dietary protein or vitamin E (VE) on oxidative damage to DNA, lipids, and protein in the liver after total body irradiation (TBI) with X-rays at 1 or 4 Gy. Levels of 8-hydroxydeoxyguanosine, thiobarbituric acid-reactive substances, and protein carbonyls in the liver did not differ among the groups that did not receive TBI. However, oxidative damage to lipids and protein was increased by TBI only in the 1% protein group. DNA damage, lipid peroxidation, or protein oxidation in the liver was increased by TBI in a dose-dependent manner, and the damage was consistently higher in the 1% than in the 20% protein group. In the 1% protein group, a greater decrease in relative spleen weight by TBI was also observed. Concentrations of antioxidants (vitamins C and E and glutathione) in the liver were lower and the concentration of nonheme iron in the liver was higher in the 1% than in the 20% protein group. Mice fed a 1% protein diet became susceptible to TBI-induced oxidative damage, and decreases in antioxidant levels and an increase in iron level were involved in the mechanism of this susceptibility. These results suggest that dietary VE and protein can prevent oxidative damage to DNA, lipid, and protein in mice subjected to TBI. Consumption of a VE-free diet significantly increased 8-hydroxydeoxyguanosine levels in DNA from mice fed the 1% protein diet with TBI, but such changes were not detected in DNA from mice fed the 20% protein diet.
Department of Food Science Research for Health, National Institute of Health and Nutrition, Tokyo 162-8636, Japan. mhjrm@nih.go.jp
Sung Jae
SJ
Shin
Kazuhiko
K
Yamada
D000080242:8-Hydroxy-2'-Deoxyguanosine; D000704:Analysis of Variance; D000818:Animals; D000975:Antioxidants / Q000008:administration & dosage / Q000494:pharmacology* / Q000528:radiation effects; D001205:Ascorbic Acid / Q000528:radiation effects; D004247:DNA / Q000528:radiation effects*; D003849:Deoxyguanosine / Q000031:analogs & derivatives* / Q000528:radiation effects; D004044:Dietary Proteins / Q000008:administration & dosage / Q000494:pharmacology*; D005978:Glutathione / Q000528:radiation effects; D008055:Lipids / Q000528:radiation effects*; D008099:Liver / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D019159:Nonheme Iron Proteins / Q000528:radiation effects; D018384:Oxidative Stress / Q000528:radiation effects*; D011506:Proteins / Q000528:radiation effects*; D017392:Thiobarbituric Acid Reactive Substances / Q000528:radiation effects; D014810:Vitamin E / Q000008:administration & dosage / Q000494:pharmacology* / Q000528:radiation effects; D014916:Whole-Body Irradiation / Q000009:adverse effects*
D000975:Antioxidants; D004044:Dietary Proteins; D008055:Lipids; D019159:Nonheme Iron Proteins; D011506:Proteins; D017392:Thiobarbituric Acid Reactive Substances; D014810:Vitamin E; D000080242:8-Hydroxy-2'-Deoxyguanosine; D004247:DNA; D003849:Deoxyguanosine; D005978:Glutathione; D001205:Ascorbic Acid