Dietary antioxidants and behavioral enrichment enhance neutrophil phagocytosis in geriatric Beagles.

TitleDietary antioxidants and behavioral enrichment enhance neutrophil phagocytosis in geriatric Beagles.
Publication TypeJournal Article
Year of Publication2006
AuthorsHall JA, Picton RA, Finneran PS, Bird KE, Skinner MM, Jewell DE, Zicker S
JournalVeterinary immunology and immunopathology
Volume113
Issue1-2
Pagination224-33
Date Published2006 Sep 15
ISSN0165-2427
KeywordsAging, alpha-Tocopherol, Animals, Antioxidants, Ascorbic Acid, Behavior, Animal, Carnitine, CD4-Positive T-Lymphocytes, CD8-Positive T-Lymphocytes, Dogs, Female, Flow Cytometry, Immunophenotyping, Leukotriene B4, Longitudinal Studies, Male, Neutrophil Activation, Neutrophils, Phagocytosis, Physical Conditioning, Animal, Thioctic Acid, Tocopherols, Tumor Necrosis Factor-alpha
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.

Alternate JournalVet. Immunol. Immunopathol.