Age-Dependent Stress Response DNA Demethylation and Gene Upregulation Accompany Nuclear and Skeletal Muscle Remodeling Following Acute Resistance-Type Exercise in Rats

Details

• Personal Author:
  Baker BA ; Rader EP
• Description:
  Efficacy of high-intensity resistance exercise becomes progressively compromised with aging. Previously, to investigate this, we developed a rodent model of high-intensity training consisting of stretch-shortening contractions (SSCs) and determined that following one month of training, young rats exhibit a robust stress response and 20% performance increase, whereas old rats display a muted stress response and 30% performance decrease. Whether these age-specific responses occur early in training and constitute primary factors in adaptation/maladaptation was not addressed. The aim of the present study was to characterize performance, remodeling, and stress response transcriptional profile 6-120 h following acute SSC exposure. For young rats, the stress response pathway was highly regulated (>/=20 differentially expressed genes at each time point) and was accompanied by robust DNA demethylation, tissue remodeling, and isometric torque recovery. For old rats, a muted transcriptional profile (13 and 2 differentially expressed genes at 6 and 120 h, respectively) coincided with deficiencies in demethylation, muscle remodeling, and torque recovery. These findings occurred in the context of heightened chronic levels of stress response gene expression with aging. This demonstrates that age-related constitutive elevations in stress response gene expression was accompanied by diminished SSC-induced responsiveness in epigenomic regulation and tissue remodeling. [Description provided by NIOSH]
• Subjects:
  Aging Laboratories Musculoskeletal System Occupational Health Safety
• Keywords:
  Author Keywords: Dorsiflexor Muscles Bioinformatics Dynamometer Fischer 344XBrown Norway Rats Gene Expression Gene Regulation Laboratory Animals Molecular Biology Muscles Musculoskeletal System Performance Tests Physical Exercise Proteins Skeletal Muscle Stretch-shortening Contractions Tissue Distribution

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• ISSN:
  2371-1671
• Document Type:
  Text
• Genre:
  Journal Article
• Place as Subject:
  OSHA Region 3 ; West Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  HELD - Health Effects Laboratory Division
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  455-473
• Volume:
  5
• Issue:
  1
• NIOSHTIC Number:
  nn:20060712
• Citation:
  Facets 2020 Jun; 5(1):455-473
• Contact Point Address:
  Erik P. Rader, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Morgantown, WV 26505, USA
• Email:
  WLZ4@cdc.gov
• Federal Fiscal Year:
  2020
• Peer Reviewed:
  True
• Source Full Name:
  Facets
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:40cd4a89b82de28f8a9905afddd3831ad2fd0a78c1235ad1977c409736995cfd62708e023cadba67713dddb6f245cbddf092aa4ac353d27ff5efba4a6a1d9c1c
• Download URL:
  https://stacks.cdc.gov/view/cdc/224543/cdc_224543_DS1.pdf
• File Type:
  [PDF - 825.41 KB ]