The Time Course of Inflammatory Biomarkers Following a One-Hour Exercise Bout in Canines: A Pilot Study

SIMPLE SUMMARY: The purpose of this study is to generate preliminary data on the inflammatory effects of an hour of hunting in dogs. Four basset hounds were set out to find a scent and freely adopted running or walking over wooded terrain for one hour. Blood samples were obtained before exercise and 1, 2, 4, 6, and 10 h after the end of the exercise for analysis of markers of inflammation (prostaglandin E(2) (PGE(2)), nitric oxide (NO), interleukin 1β (IL-1β)), tumour necrosis factor-α (TNF-α)), and inflammation resolution (resolvin D1 (RvD1)). There was an increase in inflammation one hour after the exercise, shown by a significant increase in PGE(2). Following the peak, PGE(2) steadily declined at the same time as RvD1 increased, with RvD1 peaking at six hours. This pilot study provides evidence that dogs that undergo an hour of hunt exercise experience transient inflammation that peaks one hour after the end of exercise; inflammation resolution peaks six hours after the end of exercise. Future studies should seek to further understand the distinct and combined roles of PGE(2) and RvD1 in dog adaptation to exercise stress. ABSTRACT: There is little information available to describe the inflammatory consequences of and recovery from moderate-intensity exercise bouts in hunting dogs. The purpose of the current study is to generate pilot data on the appearance and disappearance of biomarkers of inflammation and inflammation resolution following a typical one-hour exercise bout in basset hounds. Four hounds were set out to find a scent and freely adopted running or walking over wooded terrain for approximately one hour. Venous blood samples were obtained before the exercise and at 1, 2, 4, 6, and 10 h following cessation of exercise and were analyzed for biomarkers of inflammation (prostaglandin E(2) (PGE(2)), nitric oxide (NO), interleukin 1β (IL-1β)) tumour necrosis factor-α (TNF-α)), and inflammation resolution (resolvin D1 (RvD1)). There was an increase in inflammation one hour after the exercise, shown by a significant increase in PGE(2). Following this peak, PGE(2) steadily declined at the same time as RvD1 increased, with RvD1 peaking at six hours. This pilot study provides evidence that dogs that undergo an hour of hunt exercise experience transient inflammation that peaks one hour after the end of exercise; inflammation resolution peaks six hours after the end of exercise. Future studies should seek to further understand the distinct and combined roles of PGE(2) and RvD1 in dog adaptation to exercise stress.