Upregulation of IL-1β/TGF-β1 and hypoxia relate to molecular mechanisms underlying immobilization-induced muscle contractureUpregulation of IL-1β/TGF-β1 and hypoxia relate to molecular mechanisms underlying immobilization-induced muscle contracture IL-1β/TGF-β1の発現と低酸素状態の惹起は不動に伴う筋性拘縮の分子メカニズムに関与する
427 , 2015-03-20 , John Wiley and Sons Inc.
Introduction: In this study we investigated the molecular mechanism underlying muscle contracture in rats. Methods: The rats were divided into immobilization and control groups, and soleus muscles of the right and left sides were selected for analyses. Results: The levels of CD11b and α-SMA protein, IL-1β, and TGF-β1 mRNA, and type I and III collagen protein and mRNA were significantly greater in the immobilization group than in the control group at all time-points. HIF-1α mRNA levels were significantly higher in the immobilization group at 4 weeks. Moreover, HIF-1α, α-SMA, and type I collagen levels were significantly higher at 4 weeks than at 1 and 2 weeks in the immobilization group. Conclusions: In the early stages of immobilization, upregulation of IL-1β/TGF-β1 via macrophages may promote fibroblast differentiation that could affect muscle contracture. The soleus muscle became hypoxic in the later stages of immobilization, suggesting that hypoxia influences the progression of muscle contracture.