title: Aging and regeneration in vertebrates.
abstract: Aging is marked by changes that affect organs and resident stem cell function. Shorting of telomeres, DNA damage, oxidative stress, deregulation of genes and proteins, impaired cell-cell communication, and an altered systemic environment cause the eventual demise of cells. At the same time, reparative activities also decline. It is intriguing to correlate aging with the decline of regenerative abilities. Animal models with strong regenerative capabilities imply that aging processes might not be affecting regeneration. In this review, we selectively present age-dependent changes in stem/progenitor cells that are vital for tissue homeostasis and repair. In addition, the aging effect on regeneration following injury in organs such as lung, skeletal muscle, heart, nervous system, cochlear hair, lens, and liver are discussed. These tissues are also known for diseases such as heart attack, stroke, cognitive impairment, cataract, and hearing loss that occur mostly during aging in humans. Conclusively, vertebrate regeneration declines with age with the loss of stem/progenitor cell function. Future studies on improving the function of stem cells, along with studies in fish and amphibians where regeneration does not decline with age, will undoubtedly provide insights into both processes.
authors: Department of Biology and Center for Tissue Regeneration and Engineering, University of Dayton, Dayton, Ohio, USA.
authors: Konstantinos
authors: K
authors: Sousounis
authors: Department of Chemical and Materials Engineering and Center for Tissue Regeneration and Engineering, University of Dayton, Dayton, Ohio, USA.
authors: Joelle A
authors: JA
authors: Baddour
authors: Department of Biology and Center for Tissue Regeneration and Engineering, University of Dayton, Dayton, Ohio, USA. Electronic address: ptsonis1@udayton.edu.
authors: Panagiotis A
authors: PA
authors: Tsonis
mesh_terms: D000375:Aging; D000818:Animals; D004260:DNA Repair; D042783:Endothelial Cells / Q000502:physiology; D006198:Hair Cells, Auditory / Q000502:physiology; D006412:Hematopoietic Stem Cells / Q000502:physiology; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology; D009132:Muscles / Q000166:cytology / Q000473:pathology; D009206:Myocardium / Q000473:pathology; D009474:Neurons / Q000378:metabolism; D012038:Regeneration / Q000502:physiology*; D013234:Stem Cells / Q000166:cytology / Q000502:physiology; D014714:Vertebrates / Q000502:physiology*
keywords: Aging; Aging-related disease; Regeneration; Stem cell function