Basement membrane recovery process in rat soleus muscle after exercise-induced muscle injury. (3rd September 2021)

• Record Type: Journal Article
• Authors: Kanazawa, Yuji; Nagano, Mamoru; Koinuma, Satoshi; Sujino, Mitsugu; Minami, Yoichi; Sugiyo, Shinichi; Takeda, Isao; Shigeyoshi, Yasufumi
• Is Part Of: Connective tissue research. Volume 62:Number 5(2021)
• Page Start: 519
• Page End: 530
• Publication Date: 2021-09-03
• Subjects: Basement membrane -- muscle injury -- recovery -- fibroblast -- soleus muscle; Connective tissues -- Periodicals; 616.770072
• DOI: 10.1080/03008207.2020.1791839
• Languages: English
• ISSNs: 0300-8207

Abstract

ABSTRACT: Purpose: Collagen IV is a component of the basement membrane (BM) that provides mechanical support for muscle fibers. In addition, transcription factor 4 (TCF4) is highly expressed in muscle connective tissue fibroblasts and regulates muscle regeneration. However, the expression of collagen IV and TCF4 (+) cells in response to exercise-induced muscle injury is not well known. Here, we investigated the expression and localization of collagen IV and TCF4 (+) cells during the recovery process after muscle injury induced by different exercise loads. Materials and Methods: Muscle injury was observed in the soleus muscle of young Wistar rats after 12 or 18 sets—downhill running (DR) on a treadmill. After running, the rats were permitted to recover for a period of 0.5 days, 2 days, or 7 days. Results: Ectopic localization of collagen IV in injured muscle fibers was observed after DR, and the number increased at 0.5 days after 18 sets DR and at 2 days after 12 or 18 sets DR as compared to the number observed at baseline. BM disruption was observed after DR. TCF4 (+) cells appeared in the inside and around injured muscle fibers at 0.5 day of recovery. After 18 sets DR, TCF4 (+) cells were more abundant for a longer period than that observed after 12 sets DR. Conclusions: DR induces BM disruption accompanied by muscle fiber damage. It is possible that BM destruction may be accompanied by muscle damage and that TCF4 (+) cells contribute to muscle fiber and BM recovery.