Aging of the mammalian gastrointestinal tract: a complex organ system

Saffrey, M. Jill (2014). Aging of the mammalian gastrointestinal tract: a complex organ system. AGE - The Journal of the American Aging Association, 36(3) pp. 1019–1032.




Gastrointestinal disorders are a major cause of morbidity in the elderly population. The gastrointestinal tract is the most complex organ system; its diverse cells perform a range of functions essential to life, not only secretion, digestion, absorption and excretion, but also, very importantly, defence. The gastrointestinal tract acts not only as a barrier to harmful materials and pathogens but also contains the vast number of beneficial bacterial populations that make up the microbiota. Communication between the cells of the gastrointestinal tract and the central nervous and endocrine systems modifies behaviour; the organisms of the microbiota also contribute to this brain–gut–enteric microbiota axis. Age-related physiological changes in the gut are not only common, but also variable, and likely to be influenced by external factors as well as intrinsic aging of the cells involved. The cellular and molecular changes exhibited by the aging gut cells also vary. Aging intestinal smooth muscle cells exhibit a number of changes in the signalling pathways that regulate contraction. There is some evidence for age-associated degeneration of neurons and glia of the enteric nervous system, although enteric neuronal losses are likely not to be nearly as extensive as previously believed. Aging enteric neurons have been shown to exhibit a senescence-associated phenotype. Epithelial stem cells exhibit increased mitochondrial mutation in aging that affects their progeny in the mucosal epithelium. Changes to the microbiota and intestinal immune system during aging are likely to contribute to wider aging of the organism and are increasingly important areas of analysis. How changes of the different cell types of the gut during aging affect the numerous cellular interactions that are essential for normal gut functions will be important areas for future aging research.

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  • Item ORO ID
  • 40748
  • Item Type
  • Journal Item
  • ISSN
  • 1574-4647
  • Project Funding Details
  • Funded Project NameProject IDFunding Body
    'Diet-related death of neurons in the ageing gut: causes and effects’108/SAG10013BBSRC (Biotechnology and Biological Sciences Research Council)
    'Integrated analysis of the impact of age-associated neuronal and enteroendocrine changes on normal bowel functions’BB/G015988/1BBSRC (Biotechnology and Biological Sciences Research Council)
  • Keywords
  • enteric nervous system; interstitial cells; intestinal smooth muscle; intestinal immune system; mucosal epithelium; stem cells; diet; microbiota
  • Academic Unit or School
  • Faculty of Science, Technology, Engineering and Mathematics (STEM) > Life, Health and Chemical Sciences
    Faculty of Science, Technology, Engineering and Mathematics (STEM)
  • Copyright Holders
  • © 2013 The Authors
  • Depositing User
  • Jill Saffrey