Acute stressor exposure facilitates innate immunity more in physically active than in sedentary rats.
Most previous stress-immune research focused on the immunosuppressive effects of stress on acquired immunity. More recently, it has become clear that acute stressor exposure can potentiate innate, as well as suppress acquired, immunity. For example, acute stress improves recovery from bacterial inflammation, a classic in vivo measure of innate immunity. The previous work was done in sedentary organisms. Physical activity status can modulate the impact of stress on immune function. The following studies tested the hypothesis that the effect of stress on inflammation after subcutaneous challenge with bacteria (Escherichia coli) is facilitated by physical activity. The results were that sedentary, stressed rats resolved their inflammation 1-2 days faster and have increased circulating neutrophils compared with their nonstressed, sedentary counterparts. In contrast, physically active, stressed rats resolve their inflammation 3-4 days faster and have increased circulating and inflammatory site neutrophils compared with their nonstressed counterparts. Importantly, the beneficial impact of stress on inflammation recovery and neutrophil migration was greater in the physically active, than sedentary, stressed rats. Thus physical activity status facilitates the positive effect of acute stress on innate immunity.
Fleshner
Monika
M
Department of Kinesiology and Applied Physiology and the Center for Neuroscience, University of Colorado, Boulder, Colorado 80309-0354, USA. fleshner@colorado.edu
Campisi
Jay
J
Deak
Terrence
T
Greenwood
Ben N
BN
Kintzel
Jennifer A
JA
Leem
Ted H
TH
Smith
Taro P
TP
Sorensen
Bristol
B
D000818:Animals; D002452:Cell Count; D004597:Electroshock; D004926:Escherichia coli / Q000276:immunology; D007113:Immunity, Innate / Q000502:physiology*; D007249:Inflammation / Q000276:immunology; D007958:Leukocyte Count; D008297:Male; D009504:Neutrophils / Q000276:immunology / Q000473:pathology; D005082:Physical Exertion / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012867:Skin / Q000276:immunology / Q000473:pathology; D013047:Specific Pathogen-Free Organisms; D013312:Stress, Physiological / Q000276:immunology*