Oat beta-glucan can counteract the exercise-induced increased risk for
upper respiratory tract infection (URTI) in mice, which is at least partly mediated by its effects on lung macrophages. Substantial evidence in humans indicates that
carbohydrate-containing sports drinks can offset the decreased immune function associated with stressful exercise. However, no studies in animals or humans have directly examined their effects on URTI using a controlled virus-challenge model. We examined the effects of
sucrose feedings alone and in combination with
oat beta-glucan on susceptibility to
infection and on macrophage
antiviral resistance in mice following stressful exercise. These effects were also examined in rested, nonimmunocompromised control mice. Mice were assigned to one of four groups: H(2)O (water),
sucrose (S),
oat beta-glucan (ObetaG), and
sucrose +
oat beta-glucan (S+ObetaG). ObetaG and S treatments consisted of a
solution of 50% ObetaG and 6%
sucrose, respectively, and were administered in
drinking water for 10 consecutive days. Exercise consisted of a treadmill run to
fatigue performed on three consecutive days. Mice were then intranasally inoculated with a standardized dose of herpes simplex virus 1 (HSV-1) and monitored for morbidity and mortality for 21 days. Additional mice were used to determine macrophage
antiviral resistance. In the exercise experiment, S, ObetaG, and S+ObetaG all reduced morbidity (P < 0.05), while only S+ObetaG reduced mortality (P < 0.05). Macrophage
antiviral resistance was also increased in S, ObetaG, and S+ObetaG treatments (P < 0.05). In resting controls, S and S+ObetaG reduced morbidity and mortality (P < 0.05) and showed a trend toward increased macrophage
antiviral resistance. There was no significant additive effect of S and ObetaG in either control or exercised animals. These data extend our previous work on the benefits of
oat beta-glucan to show that
sucrose feedings have similar effects on susceptibility to respiratory
infection and macrophage
antiviral resistance in both resting controls and following exercise stress.