Moderate exercise is associated with enhanced antigen-specific cytokine, but not IgM antibody production in aged mice

It has been suggested that moderate exercise may modulate the immune respon se in the elderly. We investigated whether moderate exercise had an effect on the immune response to viral infection in both young (2-4 months) and ol der (16-18 months) male BALB/cJ mice. Exercised (EX) mice ran on a treadmil l for 8 weeks at a gradually increasing speed and duration whereas control (CON) mice were only handled briefly during each exercise session and then returned to their cages. Mice were infected with herpes simplex virus type 1 (HSV-1) 24 h post-exercise. Serum IgM anti-HSV antibody, HSV-1 specific T h1/Th2 cytokine production by spleen cells, and cytokine production by alve olar cells were measured 7 days post-infection. In the aged mice, exercise was associated with an enhanced production of the HSV-1 specific Th1-associ ated cytokines, interleukin (IL)-2 and interferon (IFN)-gamma, but had no e ffect on the Th2-associated cytokine IL-10 or IgM antibody. No effect of ex ercise was observed in young mice. IL-12 production was not altered by exer cise, but aging was associated with altered IL-12 production in a tissue-sp ecific manner. In conclusion, moderate exercise was associated with increas ed antigen-specific IL-2 and IFN-gamma production in response to viral chal lenge in older mice. (C) 2001 Elsevier Science Ireland Ltd. All rights rese rved.