For example, it was shown that the levels of interleukin (IL)-1 and tumor necrosis factor (TNF) -α in substantia nigra and serum from patients with PD were significantly increased, which activated downstream signaling pathways and led to neurodegeneration through the mechanisms of mitochondrial dysfunction and apoptosis (Liddelow et al., 2017). This evidence concerns the gene TNF and Parkinson disease.