After mild DNA damage by a variety of environmental insults PARP-1 activates the repair machinery, but after severe damage PARP-1 becomes highly activated and contributes to nuclear cell-death signaling by depleting NAD+ and ATP. It may also cause apoptosis-inducing factor (AIF) to translocate to the nucleus. Free PolyADP-ribose (PAR) and associated molecules may elicit other pro-apoptotic effects.
Understanding the mechanisms that underlie aging remains a bedeviling problem, but not because of a lack of answers. If anything, there seem to be too many answers – or at least enticing clues – each leading in different directions.
Thus, researchers are bound to get excited when a single molecule appears to play roles in several perceived longevity pathways, raising hopes that one could weave a coherent theory. Several strands of evidence have linked PolyADP-ribose polymerase-1 (PARP-1) to potential aging-associated processes such as DNA-repair, telomere maintenance, and apoptosis. But many still question PARP's ...
