Oxidative DNA damage as a marker of aging in WI-38 human fibroblasts

Exp Gerontol. 2002 May;37(5):647-56. doi: 10.1016/s0531-5565(02)00005-0.


Cause-effect relationships between oxidative stress, DNA damage and aging were investigated in WI-38 human diploid fibroblasts at 21, 41 or 58 population doublings (PDs), corresponding to young, middle age or old fibroblasts, respectively. Oxidative DNA damage was evaluated by immunohistochemical detection of 8-hydroxy-2'deoxyguanosine (8-OHdG) adducts or by single cell microgel electrophoresis (COMET assay). Aging was evaluated by growth rate, senescence-associated-beta-galactosidase (SA-beta galactosidase) activity, cell cycle distribution, and expression of p21. Our results demonstrate that (i) oxidative DNA damage is proportional to the age of cells (ii) DNA damage in old/58 PDs cells reflects both an increased susceptibility to oxidative stress, induced by acute exposure to sub-lethal concentrations of hydrogen peroxide (H(2)O(2)), and a reduced efficiency of repair mechanisms. We also show that mild chronic oxidative stress, induced by prolonged exposure to 5 microM H(2)O(2), accelerates aging in fibroblasts. In fact, this treatment increased 8-OHdG levels, SA-beta-galactosidase activity, and G0/G1 cell cycle arrest in middle age/41 PDs, making them similar to H(2)O(2)-untreated old/58 PDs cells. Although other mechanisms may concur in mediating the effects of H(2)O(2), these results lend support to the concept that oxidative stress may be a key determinant of aging. Measurements of oxidative DNA damage might therefore be exploited as reliable marker of cellular aging.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 8-Hydroxy-2'-Deoxyguanosine
  • Biomarkers
  • Cell Cycle / drug effects
  • Cell Line
  • Cellular Senescence / physiology*
  • DNA Damage*
  • DNA Repair
  • Deoxyguanosine / analogs & derivatives*
  • Deoxyguanosine / metabolism
  • Fibroblasts / cytology
  • Fibroblasts / drug effects
  • Fibroblasts / metabolism
  • Humans
  • Hydrogen Peroxide / toxicity
  • Oxidation-Reduction
  • Oxidative Stress
  • beta-Galactosidase / metabolism


  • Biomarkers
  • 8-Hydroxy-2'-Deoxyguanosine
  • Hydrogen Peroxide
  • beta-Galactosidase
  • Deoxyguanosine