title: Age-related changes in oxidative mechanisms and LTP are reversed by dietary manipulation.
abstract: Aged rats exhibit an impaired ability to sustain long-term potentiation in dentate gyrus which correlates with a decrease in arachidonic acid concentration. Here we confirm the previous finding that dietary supplementation with arachidonic acid and its precursor, gamma-linolenic acid, reversed the impairment in LTP in aged rats and report that there is a significant correlation between membrane arachidonic acid concentration and response to tetanic stimulation. We observed that age was associated with decreases in the concentration of vitamins C and E and increased activity of superoxide dismutase, indicative of a compromise in antioxidative defenses; these changes were paralleled by increases in interleukin-1beta (IL-1beta) concentration and lipid peroxidation. Dietary manipulation restored polyunsaturated fatty acid concentrations to values observed in tissue prepared from young rats and reversed the age-related changes in vitamins E and C, IL-1beta concentration and superoxide dismutase activity. We propose that these changes reverse the increase in lipid peroxidation and thereby the age-related change in polyunsaturated fatty acids.
authors.affiliation: Department of Physiology, Trinity College, Dublin, Ireland.
authors.forename: B M
authors.initials: BM
authors.lastname: McGahon
authors.forename: C A
authors.initials: CA
authors.lastname: Murray
authors.forename: D F
authors.initials: DF
authors.lastname: Horrobin
authors.lastname: Lynch
mesh_terms: D000375:Aging / Q000378:metabolism* / Q000502:physiology*; D000704:Analysis of Variance; D000818:Animals; D016718:Arachidonic Acid / Q000378:metabolism; D001921:Brain / Q000378:metabolism* / Q000502:physiology*; D018891:Dentate Gyrus / Q000378:metabolism / Q000502:physiology; D004032:Diet; D018698:Glutamic Acid / Q000378:metabolism; D015227:Lipid Peroxidation; D017774:Long-Term Potentiation / Q000502:physiology*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D017962:alpha-Linolenic Acid / Q000378:metabolism
chemical_list: D017962:alpha-Linolenic Acid; D016718:Arachidonic Acid; D018698:Glutamic Acid