Molecular therapy for aging-associated diseases and Lifespan extension: Nicotinamide riboside, a pyridine-nucleoside form of vitamin B3 and precursor to NAD+, increases NMN/NAD levels, decreases interaction of DBC1 with PARP1, increases PARP1 activity, promotes DNA repair, augments tolerance against radiation, cancer and aging, via down-regulation of its target gene, 31/December/2018, 6.55 pm