title: Beneficial effects of cannabinoid receptor type 2 (CB2R) in injured skeletal muscle post-contusion.
abstract: The aim of the current study was to investigate the effects of cannabinoid receptor type 2 (CB2R) on the repair process of injured skeletal muscle, which could potentially lay solid foundations as a novel target for curing muscular fibrosis in future. A standardized rat model of skeletal muscle contusion was established, where rats were treated with the CB2R agonist JWH-133 or antagonist AM-630. The in vivo results revealed that CB2R activation with JWH-133 significantly diminished the fibrotic areas, down-regulated the mRNA levels of collagen type I/ІІІ and augmented the number of multinucleated regenerating myofibers in the injured zones. The reasons leading to the aforementioned results were directly attributable to decreased mRNA levels of TGF-β1, FN-EIIIA and α-SMA, reduced accumulation of myofibroblasts, and concomitantly increased mRNA levels of matrix metalloproteinase-1/2. However, we observed contrasting changes in rats treated with the CB2R antagonist AM-630. These results revealed multiple effects of CB2R in systematically inhibiting fibrotic formation and improving muscle regeneration, alongside its potential for clinical application in patients with skeletal muscle injuries and diseases.
authors.affiliation: Department of Forensic Pathology, China Medical University School of Forensic Medicine, Shenyang, and Collaborative Innovation Center of Judicial Civilization and Key Laboratory of Evidence Science, China University of Political Science and Law, Ministry of Education, Beijing, China.
authors.forename: Tianshui
authors.initials: T
authors.lastname: Yu
authors.affiliation: Collaborative Innovation Center of Judicial Civilization and Key Laboratory of Evidence Science, China University of Political Science and Law, Ministry of Education, Beijing, China.
authors.forename: Xu
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Forensic Pathology, China Medical University School of Forensic Medicine, Shenyang, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Zhao
authors.affiliation: Department of Forensic Pathology, China Medical University School of Forensic Medicine, Shenyang, China.
authors.forename: Jilong
authors.initials: J
authors.lastname: Zheng
authors.affiliation: Department of Forensic Pathology, China Medical University School of Forensic Medicine, Shenyang, China.
authors.forename: Liqiang
authors.initials: L
authors.lastname: Li
authors.affiliation: Department of Forensic Pathology, China Medical University School of Forensic Medicine, Shenyang, China.
authors.forename: Wenxiang
authors.initials: W
authors.lastname: Ma
authors.affiliation: Department of Forensic Pathology, China Medical University School of Forensic Medicine, Shenyang, China.
authors.forename: Shutao
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Department of Forensic Pathology, China Medical University School of Forensic Medicine, Shenyang, China. dwguan2014@126.com.
authors.forename: Dawei
authors.initials: D
authors.lastname: Guan
mesh_terms: D000818:Animals; D002186:Cannabinoids / Q000494:pharmacology; D003288:Contusions / Q000378:metabolism* / Q000473:pathology; D005355:Fibrosis / Q000378:metabolism / Q000473:pathology; D007211:Indoles / Q000494:pharmacology; D008297:Male; D018482:Muscle, Skeletal / Q000187:drug effects / Q000293:injuries* / Q000378:metabolism* / Q000473:pathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D043885:Receptor, Cannabinoid, CB2 / Q000819:agonists* / Q000037:antagonists & inhibitors* / Q000378:metabolism; D012038:Regeneration / Q000187:drug effects*; D014945:Wound Healing / Q000187:drug effects
chemical_list: D002186:Cannabinoids; D007211:Indoles; D043885:Receptor, Cannabinoid, CB2; C432747:1,1-dimethylbutyl-1-deoxy-Delta(9)-THC; C094023:iodopravadoline