BCL2 and Parkinson disease: Although neurodegenerative disorders, including Parkinson’s disease (PD), Alzheimer’s disease (AD), Huntington’s disease (HD), and amyotrophic lateral sclerosis (ALS), differ in their pathological genetic changes and degeneration of distinct neuron subsets, the evidence for the activation of apoptotic pathway (such as Caspase-3/8/9, Bax overexpression, and Bcl-2 reduction) in these disorders has been provided by many studies [8–10].