TNF and Parkinson disease: A study revealed that the release of CCL2 levels increasedwhen SH-SY5Y cells were incubated with α-synuclein to induceneuropathological lesions and the pathogenesis of PD.43 CCL2 is the most potent activator of CCR2 (C–C chemokinereceptor type 2) signaling, and the upregulation of CCR2 by CCL2 isassociated with inflammatory diseases in the central nervous systemmultiple sclerosis, Alzheimer disease, and ischemic stroke.44,45 Neurodegeneration and neuronal death in neurodegenerative diseasesprimarily cause increased proinflammatory regulators such as IL-1β,TNF, IL-6, IL-8, CCL2, and CCL5.9