title: Dietary antioxidants and behavioral enrichment enhance neutrophil phagocytosis in geriatric Beagles.
abstract: The study objective was to determine the effects of feeding food enriched in antioxidants and a program of environmental/cognitive enrichment on selected ex vivo assays of inflammatory and immune cells in healthy geriatric Beagle dogs (n=21). Four groups of dogs were tested using a 2 x 2 factorial design. The 2-year longitudinal study included both nutritional (control food or antioxidant-fortified food) and behavioral (normal level or cognitive enrichment) interventions. Behavior enrichment included increased exercise, environmental enrichment, and a series of learning tasks. Phagocytosis of opsonized latex-coated beads by peripheral blood neutrophils was measured by flow cytometry and found to be significantly increased in dogs receiving both dietary antioxidants and cognitive enrichment. Simultaneous stimulation of cells with Con A and suppression with Dex resulted in decreased lymphocyte proliferation in dogs receiving both dietary antioxidants and cognitive enrichment, compared to dogs receiving dietary antioxidants or cognitive enrichment alone. There were no significant differences between the groups of dogs for percentages of CD4 and CD8 T-lymphocyte subpopulations before or after lymphocyte stimulation with Con A. These results support our hypothesis that both dietary antioxidants and behavioral enrichment enhance host defense mechanisms.
authors.affiliation: Department of Biomedical Sciences, College of Veterinary Medicine, Oregon State University, Corvallis, OR 97331, USA. Jean.Hall@oregonstate.edu
authors.forename: Jean A
authors.initials: JA
authors.lastname: Hall
authors.forename: Rebecca A
authors.initials: RA
authors.lastname: Picton
authors.forename: Phyllis S
authors.initials: PS
authors.lastname: Finneran
authors.forename: Karyn E
authors.initials: KE
authors.lastname: Bird
authors.forename: Monica M
authors.initials: MM
authors.lastname: Skinner
authors.forename: Dennis E
authors.initials: DE
authors.lastname: Jewell
authors.forename: Steven
authors.initials: S
authors.lastname: Zicker
mesh_terms: D000375:Aging / Q000276:immunology; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001205:Ascorbic Acid / Q000494:pharmacology; D001522:Behavior, Animal / Q000502:physiology; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology; D002331:Carnitine / Q000494:pharmacology; D004285:Dogs / Q000276:immunology*; D005260:Female; D005434:Flow Cytometry / Q000662:veterinary; D016130:Immunophenotyping / Q000662:veterinary; D007975:Leukotriene B4 / Q000032:analysis / Q000276:immunology; D008137:Longitudinal Studies; D008297:Male; D018375:Neutrophil Activation / Q000187:drug effects / Q000276:immunology; D009504:Neutrophils / Q000276:immunology*; D010587:Phagocytosis / Q000187:drug effects / Q000276:immunology; D010805:Physical Conditioning, Animal; D008063:Thioctic Acid / Q000494:pharmacology; D024505:Tocopherols; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis / Q000276:immunology; D024502:alpha-Tocopherol / Q000031:analogs & derivatives / Q000494:pharmacology
chemical_list: D000975:Antioxidants; D014409:Tumor Necrosis Factor-alpha; D007975:Leukotriene B4; D008063:Thioctic Acid; D024502:alpha-Tocopherol; D001205:Ascorbic Acid; D024505:Tocopherols; D002331:Carnitine