title: Dietary butter protects against ultraviolet radiation-induced suppression of contact hypersensitivity in Skh:HR-1 hairless mice.
abstract: Dietary fats modulate a wide variety of T cell functions in mice and humans. This study examined the effects of four different dietary fats, predominantly polyunsaturated sunflower oil, margarine, and predominantly saturated butter, clarified butter, on the T cell-mediated, systemic suppression of contact hypersensitivity by ultraviolet radiation in the Skh:HR-1 hairless mouse. Diets containing either 200 g/kg or 50 g/kg butter or clarified butter as the sole fat source protected against systemic photoimmunosuppression, whether the radiation source was unfiltered ultraviolet B (280-320 nm) or filtered solar simulated ultraviolet radiation (290-400 nm), in comparison with diets containing either 200 or 50 g/kg margarine or sunflower oil. There was a linear relationship (r > 0.9) between protection against photoimmunosuppression and the proportion of clarified butter in mice fed a series of 200 g/kg mixed fat diets that provided varying proportions of clarified butter and sunflower oil. The dietary fats did not modulate the contact hypersensitivity reaction in unirradiated animals. The observed phenomena were not primary due to the carotene, tocopherol, cholecalciferol, retinol, lipid hydroperoxide or the nonfat solid content of the dietary fats used and appeared to be a result of the different fatty acid composition of the fats.
authors.affiliation: Department of Veterinary Pathology, University of Sydney, New South Wales, Australia.
authors.forename: R B
authors.initials: RB
authors.lastname: Cope
authors.forename: M
authors.initials: M
authors.lastname: Bosnic
authors.forename: C
authors.initials: C
authors.lastname: Boehm-Wilcox
authors.forename: D
authors.initials: D
authors.lastname: Mohr
authors.forename: V E
authors.initials: VE
authors.lastname: Reeve
mesh_terms: D000818:Animals; D002079:Butter; D002762:Cholecalciferol / Q000032:analysis; D003877:Dermatitis, Contact / Q000532:radiotherapy*; D004041:Dietary Fats / Q000032:analysis / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004817:Epidermis / Q000737:chemistry; D005227:Fatty Acids / Q000032:analysis; D005260:Female; D006368:Helianthus; D007111:Immunity, Cellular / Q000528:radiation effects; D007165:Immunosuppression Therapy; D008383:Margarine; D051379:Mice; D008812:Mice, Hairless; D010938:Plant Oils / Q000494:pharmacology; D000074242:Sunflower Oil; D013601:T-Lymphocytes / Q000276:immunology / Q000528:radiation effects; D014466:Ultraviolet Rays; D014801:Vitamin A / Q000032:analysis
chemical_list: D004041:Dietary Fats; D005227:Fatty Acids; D010938:Plant Oils; D000074242:Sunflower Oil; D014801:Vitamin A; D002762:Cholecalciferol; D002079:Butter; D008383:Margarine