Age-dependent modification by lactate of repair of potentially lethal damage in normal human diploid fibroblasts.
We investigated age-related changes in normal human diploid fibroblasts (strain AG 1522) followed throughout their lifespan in vitro. Radiosensitivity and the capacity to repair potentially lethal radiation damage (PLD) remained constant until senescence was reached. However, the effects of incubation with lactate on PLD repair were age dependent and complex. Low millimolar concentrations of lactate increased the capacity to repair PLD, whereas higher concentrations suppressed it in a concentration-dependent manner. With increasing in vitro age, the cells became less sensitive to the modifying effects of lactate; in presenescent cells, the modifying effects of lactate on PLD repair had completely vanished.
Rutz
H P
HP
Laboratory of Radiobiology, Harvard School of Public Health, Boston, Massachusetts 02115.
Little
J B
JB
D002470:Cell Survival / Q000187:drug effects* / Q000528:radiation effects; D004247:DNA / Q000528:radiation effects*; D004260:DNA Repair / Q000187:drug effects*; D004171:Diploidy; D005347:Fibroblasts; D006801:Humans; D066298:In Vitro Techniques; D007773:Lactates / Q000494:pharmacology*; D019344:Lactic Acid
D007773:Lactates; D019344:Lactic Acid; D004247:DNA