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Updated: Jan 9, 2026
01:19
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6.0K
How stem cells age and why this makes us grow old
Norman E Sharpless1, Ronald A DePinho
1Department of Medicine, The Lineberger Comprehensive Cancer Center, The University of North Carolina, Chapel Hill, North Carolina 27599-7295, USA. nes@med.unc.edu
Nature Reviews. Molecular Cell Biology
|August 25, 2007
Summary
Aging occurs as stem cells accumulate DNA damage and face niche changes. Cancer-suppressing mechanisms may impair stem cell function, contributing to age-related diseases like frailty and diabetes.
Area of Science:
- Gerontology
- Stem Cell Biology
- Molecular Biology
Background:
- Aging is linked to stem cell dysfunction.
- Intrinsic factors (e.g., DNA damage) and extrinsic factors (niche changes) impact stem cell aging.
- Cancer suppression mechanisms (senescence, apoptosis) may inadvertently affect stem cell function.
Purpose of the Study:
- To explore the role of stem cell aging in mammalian aging.
- To investigate the contribution of declining stem cell regenerative capacity to age-associated conditions.
Main Methods:
- Review of recent data and findings on stem cell aging.
- Analysis of mechanisms of stem cell dysfunction, including DNA damage and niche alterations.
- Examination of the interplay between cancer suppression pathways and stem cell replicative capacity.
Main Results:
- Stem cells age due to intrinsic and extrinsic factors.
- Cancer-preventive mechanisms like senescence and apoptosis can reduce stem cell function.
- Reduced stem cell regenerative capacity is a key factor in aging.
Conclusions:
- A 'stem-cell hypothesis' for aging is proposed.
- Stem cell aging contributes to age-associated diseases such as frailty, atherosclerosis, and type 2 diabetes.
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