title: Epigallocatechin-3-gallate improves plantaris muscle recovery after disuse in aged rats.
abstract: Aging exacerbates muscle loss and slows the recovery of muscle mass and function after disuse. In this study we investigated the potential that epigallocatechin-3-gallate (EGCg), an abundant catechin in green tea, would reduce signaling for apoptosis and promote skeletal muscle recovery in the fast plantaris muscle and the slow soleus muscle after hindlimb suspension (HLS) in senescent animals. Fischer 344 × Brown Norway inbred rats (age 34 months) received either EGCg (50 mg/kg body weight), or water daily by gavage. One group of animals received HLS for 14 days and a second group of rats received 14 days of HLS, then the HLS was removed and they recovered from this forced disuse for 2 weeks. Animals that received EGCg over the HLS followed by 14 days of recovery, had a 14% greater plantaris muscle weight (p<0.05) as compared to the animals treated with the vehicle over this same period. Plantaris fiber area was greater after recovery in EGCg (2715.2±113.8 μm(2)) vs. vehicle treated animals (1953.0±41.9 μm(2)). In addition, activation of myogenic progenitor cells was improved with EGCg over vehicle treatment (7.5% vs. 6.2%) in the recovery animals. Compared to vehicle treatment, the apoptotic index was lower (0.24% vs. 0.52%), and the abundance of pro-apoptotic proteins Bax (-22%), and FADD (-77%) was lower in EGCg treated plantaris muscles after recovery. While EGCg did not prevent unloading-induced atrophy, it improved muscle recovery after the atrophic stimulus in fast plantaris muscles. However, this effect was muscle specific because EGCg had no major impact in reversing HLS-induced atrophy in the slow soleus muscle of old rats.
authors: Laboratory of Muscle Biology and Sarcopenia, Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, WV 26506-9227, United States; West Virginia Center for Clinical and Translational Science Institute, West Virginia University School of Medicine, Morgantown, WV 26506-9227, United States; Center for Cardiovascular and Respiratory Sciences, West Virginia University School of Medicine, Morgantown, WV 26506-9227, United States. Electronic address: salway@hsc.wvu.edu.
authors: Stephen E
authors: SE
authors: Alway
authors: Laboratory of Muscle Biology and Sarcopenia, Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, WV 26506-9227, United States; Center for Cardiovascular and Respiratory Sciences, West Virginia University School of Medicine, Morgantown, WV 26506-9227, United States.
authors: Brian T
authors: BT
authors: Bennett
authors: Laboratory of Muscle Biology and Sarcopenia, Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, WV 26506-9227, United States; Center for Cardiovascular and Respiratory Sciences, West Virginia University School of Medicine, Morgantown, WV 26506-9227, United States.
authors: Joseph C
authors: JC
authors: Wilson
authors: Discovery R&D, Abbott Nutrition, Columbus, OH, United States.
authors: Neile K
authors: NK
authors: Edens
authors: Discovery R&D, Abbott Nutrition, Columbus, OH, United States.
authors: Suzette L
authors: SL
authors: Pereira
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D001835:Body Weight / Q000187:drug effects; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D004353:Drug Evaluation, Preclinical / Q000379:methods; D038362:Glycogen Synthase Kinase 3 / Q000378:metabolism; D000071679:Glycogen Synthase Kinase 3 beta; D019417:Hindlimb Suspension / Q000379:methods; D007537:Isometric Contraction / Q000187:drug effects / Q000502:physiology; D018485:Muscle Fibers, Skeletal / Q000187:drug effects / Q000473:pathology; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000473:pathology / Q000502:physiology; D009133:Muscular Atrophy / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology; D009929:Organ Size / Q000187:drug effects; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D051381:Rats; D011914:Rats, Inbred BN; D011916:Rats, Inbred F344; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D013234:Stem Cells / Q000187:drug effects / Q000502:physiology; D016474:Weight-Bearing / Q000502:physiology
chemical_list: D002392:Catechin; C045651:epigallocatechin gallate; D000071679:Glycogen Synthase Kinase 3 beta; D051057:Proto-Oncogene Proteins c-akt; D038362:Glycogen Synthase Kinase 3
keywords: Apoptosis; Catechin; Muscle atrophy; Muscle fiber area; Muscle function; Sarcopenia