PARP1 and Alzheimer disease: Studies have shown that PARP-1 hyperactivation depletes NAD+, induces an accumulation of Poly (ADP-ribose) (PAR), and triggers mitochondrial damage in Alzheimer’s disease (AD) (Martire et al., 2015), Huntington’s disease (HD) (Cardinale et al., 2015), amyotrophic lateral sclerosis (ALS) (Kim et al., 2004), ischemic brains (Moroni, 2008), and PD (Yunjong et al., 2014).