Young (4- to 6-month-old) and aged (24- to 28-month-old) mice were exposed to 2-nitropropane (2-NP), a DNA oxidizing agent, and the ability to induce DNA polymerase β (β-pol) and AP endonuclease (APE) was determined. In contrast to the inducibility of these gene products in response to oxidative damage in young mice, aged mice showed a lack of inducibility of β-pol and APE. APE protein level and endonuclease activity were both reduced 40% (p < .01) in response to 2-NP. Accordingly, the accumulation of DNA repair intermediates in response to 2-NP differed with age. Young animals accumulated 3′OH-containing DNA strand breaks, whereas the aged animals did not. A role for p53 in the difference in DNA damage response with age is suggested by the observation that the accumulation of p53 protein in response to DNA damage in young animals was absent in the aged animals. Our results are consistent with a reduced ability to process DNA damage with age.
|Original language||English (US)|
|Number of pages||8|
|Journal||Journals of Gerontology - Series A Biological Sciences and Medical Sciences|
|State||Published - May 2006|
ASJC Scopus subject areas
- Geriatrics and Gerontology