title: Effect of dietary supplementation with white button mushrooms on host resistance to influenza infection and immune function in mice.
abstract: Previously, we showed that mice fed white button mushrooms (WBM) had enhanced immune functions known to help the body's antiviral defence. In the present study, we tested whether WBM conferred protection against viral infection. Young (4-month-old) and old (22-month-old) C57BL/6 mice were fed a diet containing 0, 2 or 10 % WBM powder for 8 weeks. Mice were then infected with influenza Puerto Rico/8/34 (H1N1), and killed at day 0 (uninfected), 2, 5 or 7 post-infection. The primary outcomes of the study were viral titre and body weight. Secondary outcomes were natural killer (NK) cell activity, lymphocyte proliferation and cytokine production. The results showed that WBM did not affect viral titre, nor did it prevent infection-induced weight loss. WBM supplementation was found to enhance NK cell activity in old mice and to increase interferon (IFN)-γ production in young and old mice under naive (uninfected) conditions, but it had no such effect after infection. The lack of a mushroom supplementation effect on NK activity and concanavalin A-stimulated IFN-γ production after infection may explain the immune system's failure to reduce viral load and weight loss in mice after influenza infection. WBM supplementation, however, did induce changes in other aspects of the immune response: it significantly increased the production of T-helper type 2 cytokines IL-4 and IL-10 in uninfected mice and pro-inflammatory cytokines IL-1β and TNF-α in infected mice. These mushroom-induced systemic changes, however, were not adequate to confer a protective effect against influenza infection.
authors.affiliation: Nutritional Immunology Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston, MA 02111, USA.
authors.forename: Yanmei
authors.initials: Y
authors.lastname: Xu
authors.forename: Lixin
authors.initials: L
authors.lastname: Na
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Ren
authors.forename: Jianguo
authors.initials: J
authors.lastname: Xu
authors.forename: Changhao
authors.initials: C
authors.lastname: Sun
authors.forename: Donald
authors.initials: D
authors.lastname: Smith
authors.forename: Simin Nikbin
authors.initials: SN
authors.lastname: Meydani
authors.forename: Dayong
authors.initials: D
authors.lastname: Wu
mesh_terms: D000363:Agaricales; D000818:Animals; D003208:Concanavalin A / Q000494:pharmacology; D004032:Diet; D060467:Disease Resistance / Q000276:immunology*; D057141:Food, Preserved; D053118:Influenza A Virus, H1N1 Subtype; D007372:Interferons / Q000096:biosynthesis; D007694:Killer Cells, Natural / Q000276:immunology; D008168:Lung / Q000821:virology; D008213:Lymphocyte Activation; D051379:Mice; D008810:Mice, Inbred C57BL; D009976:Orthomyxoviridae Infections / Q000150:complications / Q000276:immunology* / Q000517:prevention & control; D019562:Viral Load; D015431:Weight Loss
chemical_list: D003208:Concanavalin A; D007372:Interferons