Abstract
Degenerative effects on lymphoid tissues such as the thymus and Peyer's patches were observed in mice after oral administration of methyl linoleate hydroperoxide, a model of primary autoxidation products of oils, or low-molecular-weight compounds: one type of secondary autoxidation product. Immunocompetent cells such as thymus and spleen cells were modulated by feeding the mice with partially oxidized soybean oil (peroxide value, 150meq/kg) for 3 months. To evaluate the effect of in vivo lipid peroxidation on immunocompetent cells, mice were fed for 30 days on seven different dietary oils including fish oil rich in n-3 polyunsaturated fatty acids. The fish oil diet induced modulation of spleen cells and a significant increase of membranous lipid hydroperoxide (hydroperoxides of phosphatidylcholine and phosphatidylethanolamine) accumulation as a marker of oxidative senescence in red blood cells. These results suggest that dietary oxidized oils (exogenous lipid peroxides) and endogenous lipid peroxides formed in the body of animals can affect immunocompetent cells and also immune responses.