Different effects of strength and endurance exercise training on COX-2 and mPGES expression in mouse brain are independent of peripheral inflammation.
Acute endurance exercise has been shown to modulate cyclooxygenase (COX)-2 expression, which is suggested to affect neuronal plasticity and learning. Here, we investigated the effect of regular strength and endurance training on cerebral COX-2 expression, inflammatory markers in the brain, and circulating cytokines. Male C57BL/6N mice were assigned to either a sedentary control group (CG), an endurance training group (EG; treadmill running for 30 min/day, 5 times/wk, 10 wk), or a strength training group (SG; strength training by isometric holding, same duration as EG). Four days after the last bout of exercise, blood and brain were collected and analyzed using real-time PCR, Western blot, and a multiplexed immunoassay. In EG, COX-2 mRNA expression in the cortex/hippocampus increased compared with CG. A significant increase of COX-2 protein levels was observed in both cortex/hippocampus and hypothalamus of mice from the SG. Nuclear factor (NF)κB protein levels were significantly increased in mice from both exercise groups (hypothalamus). A significant increase in the expression of microsomal prostaglandin E synthase (mPGES), an enzyme downstream of COX-2, was found in the hypothalamus of both the EG and SG. While most inflammatory factors, like IL-1α, IL-18, and IL-2, decreased after training, a positive association was found between COX-2 mRNA expression (cortex/hippocampus) and plasma IL-6 in the EG. Taken together, this study demonstrates that both endurance as well as strength training induces COX-2 expression in the cortex/hippocampus and hypothalamus of mice. A potential mediator of COX-2 expression after training might be circulating interleukin (IL)-6. However, further research is necessary to elucidate the role of inflammatory pathways on brain plasticity after training.
Department of Sports Medicine, Justus-Liebig-University Giessen, Giessen, Germany; and karsten.krueger@sport.uni-giessen.de.
K
K
Krüger
Institute of Veterinary Physiology and Biochemistry, Justus-Liebig-University Giessen, Giessen, Germany.
J
J
Bredehöft
Department of Sports Medicine, Justus-Liebig-University Giessen, Giessen, Germany; and.
F C
FC
Mooren
Institute of Veterinary Physiology and Biochemistry, Justus-Liebig-University Giessen, Giessen, Germany.
C
C
Rummel
D000818:Animals; D002540:Cerebral Cortex / Q000378:metabolism* / Q000503:physiopathology; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D016207:Cytokines / Q000378:metabolism; D006624:Hippocampus / Q000378:metabolism* / Q000503:physiopathology; D007249:Inflammation / Q000378:metabolism* / Q000503:physiopathology; D015850:Interleukin-6 / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D016328:NF-kappa B / Q000378:metabolism; D010805:Physical Conditioning, Animal / Q000502:physiology*; D010807:Physical Endurance / Q000502:physiology*; D000071876:Prostaglandin-E Synthases / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D055070:Resistance Training / Q000379:methods; D012420:Running / Q000502:physiology
D016207:Cytokines; D015850:Interleukin-6; D016328:NF-kappa B; D012333:RNA, Messenger; C077623:Ptgs2 protein, mouse; D051546:Cyclooxygenase 2; D000071876:Prostaglandin-E Synthases
cyclooxygenase-2; cytokines; microsomal PGE synthase; prostaglandins; resistance exercise