The expression ofiNOS in neurons resulted in neuronal cell death which was prevented byactivation of PPARγ in vitroand in vivo [42, 43].Neuroinflammatory changes accompanied by activation of microglia and astrocytesand expression of TNFα, IL-1β, and iNOS play a pivotal role in PD [46].An increase in infiltrating CD8+ T lymphocytes and IFNγ+ cells were alsoreported in the CNS with PD. Here, CD8A is linked to Parkinson disease.