TNF and Parkinson disease: Thus, PD has neuroinflammatory disease characteristics, namely, the increased production of proinflammatory or neurotoxic factors by microglia in the SNc, such as nitric oxide (NO); reactive oxygen species (ROS); glutamate; chemokines; and cytokines such as CCL2, interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) (Table 1) [2,19,25,29,30,31].