Age-associated DNA damage is accelerated in the senescence-accelerated mice

We investigated how the DNA status correlates with the aging process in org anisms, in different organs and in tissues using two inbred strains of mice , which are genetically related but have different senescence patterns. The SAMP1 mice belong to an accelerated senescence-prone and short lived strai n, the other, SAMR1 mice are from an accelerated senescence-resistant and l ong lived strain. Using the alkaline filter elution technique, pieces of ti ssues from six organs: lung, intestine, liver, brain, muscle, and heart hav e been examined for DNA damage, mainly DNA single strand breaks. It was sho wn that in newborns the DNA damage is minimal, and it was increased signifi cantly with calendric age in all organs in both strains. Although the corre lation of DNA damage with aging differed in the different six organs, damag e was significantly higher in SAMP1 mice than SAMR1 mice at later life in a ll organs. This is another remarkable example for the strong correlation of DNA damage and aging process, especially with senescence acceleration. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.