Age-related changes of lipid peroxidation in food-restricted rats based on determination of phosphatidylcholine hydroperoxide in the plasma, liver and kidney by high-performance liquid chromatography with fluorometric post-column detection]

Age-related changes of phosphatidylcholine hydroperoxide (PCOOH) were investigated in male Dawley rats aged 3 to 18 months, either fed ad libitum or dietary restricted (maintained on 60% of ad libitum food intake). Although there are many reports dealing with age-related changes of lipid peroxidation, they were exclusively results obtained by the non-specific thiobarbituric acid method. In this study, we measured PCOOH as an index of oxidative stress by a specific assay method using high-performance liquid chromatography with fluorometric post-column detection. The PCOOH levels in ad libitum-fed rat plasma, liver and kidney increased with age. Dietary restriction significantly suppressed the age-related PCOOH accumulation in the plasma. In dietary restricted rat liver, PCOOH levels tended to be suppressed by the restriction. In dietary restricted rat kidney, they were not due to until 12 months of age, but the levels at 18-months of age were suppressed by the restriction. Life span is mainly influenced by pathologic lesions. The increase in PCOOH levels with age can cause biomembrane damage, and appears to be involved in the development of lesions. Suppression of PCOOH level by dietary restriction appears to suppress the morbid conditions which shorten life span.