title: Effects of exogenous antioxidants on the levels of endogenous antioxidants, lipid-soluble fluorescent material and life span in the housefly, Musca domestica.
abstract: Effects of exogenous antioxidant administration (0.5% and 2% ascorbate, beta-carotene and alpha-tocopherol in sucrose) on life-span, metabolic rate, activities of superoxide dismutase and catalase, levels of glutathione, inorganic peroxides and chloroform-soluble fluorescent material (lipofuscin) were examined in adult male houseflies. Administration of antioxidants at a level of 0.5% did not affect life-span, whereas, 2% ascorbate and alpha-tocopherol decreased average life-span. Metabolic rate of flies was unaffected, except by 2% ascorbate, which caused a decrease. Superoxide dismutase activity was depressed by 2% ascorbate at all ages, and by beta-carotene and alpha-tocopherol in older flies. Catalase activity was unaffected except by alpha-tocopherol at younger ages. Glutathione concentration was decreased by ascorbate and beta-carotene at both concentrations administered. Inorganic peroxides (H2O2) were increased by 2% beta-carotene and alpha-tocopherol. Only high concentrations of ascorbate and beta-carotene decreased the level of soluble fluorescent material. Results suggest that administration of exogenous antioxidants causes a compensatory depression of endogenous defenses.
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism / Q000494:pharmacology*; D002374:Catalase / Q000378:metabolism; D005456:Fluorescent Dyes / Q000378:metabolism*; D005978:Glutathione / Q000378:metabolism; D006793:Houseflies / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism; D008055:Lipids; D008136:Longevity; D010101:Oxygen Consumption / Q000187:drug effects; D012995:Solubility; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D000975:Antioxidants; D005456:Fluorescent Dyes; D008055:Lipids; D006861:Hydrogen Peroxide; D002374:Catalase; D013482:Superoxide Dismutase; D005978:Glutathione