Accelerated Aging during Chronic Oxidative Stress: A Role for PARP-1
(a) Telomere length and (b) telomerase activity in human fibroblasts during culturing in the absence (black line) or presence (grey line) of 5 nM tert-butyl hydroperoxide (t-BHP). HF cells exposed to t-BHP showed significantly shorter telomeres than nonexposed cells of the same passage number. Telomere length significantly decreased over time in nonexposed cells as well as in exposed cells. ** compared to P0 (start of the experiment); * compared to nonexposed cells of the same passage number. Mean ± SD of telomere length is shown. If telomerase activity was present, the relative telomerase activity value would be higher than 100. The values are lower than 10, which indicates that there is no telomerase activity in these cells.