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A dual role of p21 in stem cell aging

Zhenyu Ju1, Aaheli Roy Choudhury, K Lenhard Rudolph

  • 1Department of Gastroenterology, Hepatology, and Endocrinology, Medical School Hannover, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.

Annals of the New York Academy of Sciences
|April 27, 2007
PubMed

Insights

Aging impairs adult stem cell function. The p21 protein, a cell cycle inhibitor, shows dual roles in stem cell aging, protecting against acute damage but hindering function with chronic damage.

Area of Science:

  • Gerontology
  • Molecular Biology
  • Stem Cell Biology

Background:

  • Adult stem cell function declines with age, impacting organ homeostasis and regeneration.
  • Macromolecular damage accumulation during aging affects stem cell function.
  • The p21 cell cycle inhibitor is implicated in stem cell aging.

Purpose of the Study:

  • To analyze the dual roles of p21 in aging adult stem cells.
  • To investigate how p21 influences stem cell response to different types of stress during aging.

Main Methods:

  • Review of current data on p21's function in stem cell aging.
  • Analysis of p21's role in protecting against acute genotoxic stress.
  • Examination of p21's impact on stem cell function in aging telomere dysfunctional mice.

Main Results:

  • p21 protects adult stem cells from acute genotoxic stress by inhibiting the cell cycle of damaged cells.
  • p21 activation impairs stem cell function and survival in aging mice with telomere dysfunction.
  • The checkpoint function of p21 is disadvantageous in the context of chronic, persistent damage associated with aging.

Conclusions:

  • p21 exhibits a dual role in stem cell aging, acting as a protector against acute stress but a detriment during chronic aging-related damage.
  • Understanding p21's complex role is crucial for developing strategies to improve stem cell function in aging organisms.

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