Purpose： Macrophages are known to be important for healing numerous injured tissues depending on their functional phenotypes in response to different stimuli. The objective of this study was to reveal macrophage phen...Purpose： Macrophages are known to be important for healing numerous injured tissues depending on their functional phenotypes in response to different stimuli. The objective of this study was to reveal macrophage phenotypic changes involved in exercise-induced skeletal muscle injury and regeneration. Methods： Adult male Sprague-Dawley rats experienced one session of downhill running （16~ decline, 16 m/min） for 90 min. After exercise the blood and soleus muscles were collected at 0 h, 6 h, 12 h, 1 d, 2 d, 3 d, 1 w and 2 w after exercise, separately. Results： It was showed that CD6B＋ M1 macrophages mainly infiltrated into musc｜e necrotic sites at 1-3 d, while CD163＋ M2 macrophages were present in muscles from 0 h to 2 weeks after exercise. Using transmission electron microscopy, we observed activated satellite cells 1 d after exercise. Thl-associated transcripts of iNOS and Cc12 were inhibited post exercise, while COX-2 mRNA was dramatically increased 12 h after running （p 〈 0.01 ）. M2 phenotype marker Arg-1 increased 12 h and 3 d （p 〈 0.05, p 〈 0.01 ） after exercise, and Clecl0a and Mrc2 were up-regulated in muscles 12 h following exercise （p 〈 0.05, p 〈 0.05）. Conclusion： The data demonstrate the dynamic patterns of macrophage phenotype in skeletal muscle upon eccentric exercise stimuli, and M1 and M2 phenotypes perform different functions during exercise- induced skeletal muscle injury and recovery.展开更多
文摘Purpose： Macrophages are known to be important for healing numerous injured tissues depending on their functional phenotypes in response to different stimuli. The objective of this study was to reveal macrophage phenotypic changes involved in exercise-induced skeletal muscle injury and regeneration. Methods： Adult male Sprague-Dawley rats experienced one session of downhill running （16~ decline, 16 m/min） for 90 min. After exercise the blood and soleus muscles were collected at 0 h, 6 h, 12 h, 1 d, 2 d, 3 d, 1 w and 2 w after exercise, separately. Results： It was showed that CD6B＋ M1 macrophages mainly infiltrated into musc｜e necrotic sites at 1-3 d, while CD163＋ M2 macrophages were present in muscles from 0 h to 2 weeks after exercise. Using transmission electron microscopy, we observed activated satellite cells 1 d after exercise. Thl-associated transcripts of iNOS and Cc12 were inhibited post exercise, while COX-2 mRNA was dramatically increased 12 h after running （p 〈 0.01 ）. M2 phenotype marker Arg-1 increased 12 h and 3 d （p 〈 0.05, p 〈 0.01 ） after exercise, and Clecl0a and Mrc2 were up-regulated in muscles 12 h following exercise （p 〈 0.05, p 〈 0.05）. Conclusion： The data demonstrate the dynamic patterns of macrophage phenotype in skeletal muscle upon eccentric exercise stimuli, and M1 and M2 phenotypes perform different functions during exercise- induced skeletal muscle injury and recovery.
