Is cell death and replacement a factor in aging?

University of Minnesota, College of Biological Sciences, St. Paul, MN 55108, United States.
Mechanisms of Ageing and Development (Impact Factor: 3.4). 02/2007; 128(1):13-6. DOI: 10.1016/j.mad.2006.11.004
Source: PubMed

ABSTRACT The central theme of the 3rd International Conference on Functional Genomics of Ageing was tissue regeneration as a remedial strategy to address age-related cellular damage and the pathology that ensues. The conference included sessions on maintaining genome integrity and the potential of stem cells to restore function to damaged tissues. In addition to several human syndromes that appear to reflect accelerated ageing, there are now a number of mouse models that prematurely display phenotypes associated with ageing. The intent of this summary presented at the end of the conference was to: (1) discuss various human syndromes and mouse models of accelerated ageing; (2) evaluate whether the phenotypes displayed might result from an elevated rate of cell death coupled with an inability to adequately maintain cell number in various tissues with increasing age; and (3) discuss whether similar events may be occurring during normal ageing, albeit much more slowly.

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    • "However, there is no evidence for increased apoptosis during aging, instead it seems that the decline in apoptosis itself leads to the accumulation of damage and functional defects (e.g. Wang, 1997; Zhang and Herman, 2002; Warner, 2007). Replicative senescence in vitro is associated with an increase in resistance to apoptosis (Wang, 1997). "
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    • "The homeostatic regulation of cell numbers in normal tissues reflect a precise balance between cell proliferation and cell death. Programmed cell death (apoptosis) provides a protective mechanism of protection from cancer, by removing senescent, DNA damaged, or diseased cells that could potentially interfere with normal function or lead to neoplastic transformation (Hanahan and Weinberg, 2000; Warner, 2007). Apoptosis plays a substantial role in many other aspects of aging and cancer, including control of the life span of most members of the immune complex, and the rate of growth of tumors (Zhang and Herman, 2002). "
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