Relation between oxidative damage and dietary protein: marginal protein level which modulates oxidative damage in mice with total body irradiation

Mice were fed different levels of dietary protein (8%, 11%, 14%, 17% or 20%) and then gave total body irradiation (TBI) with X-rays. The levels of lipid peroxides and protein carbonyls in the liver and chromosomal damage in bone marrow did not differ among the groups, which were not received TBI. However, the oxidative damage of lipid and protein in the liver increased due to TBI only in the 8% or 11% protein group. The chromosomal damage in bone marrow due to TBI was higher in the 8% or 11% protein group than those in the 14%, 17% or 20% protein group. Concentrations of antioxidants (vitamins C, E and GSH) in the liver were lower, and the concentrations of non-heme iron in the liver were higher in the 8% or 11% protein group than those in the 14%, 17% or 20% protein group.