IL6 and Parkinson disease: Besides, changed levels of Urinary 8-hydroxydeoxyguanosin (Urinary 8-OHdGe) and proinflammatory cytokines such as tumor necrosis factor α (TNF-α), interleukin 6 (IL-6) and interleukin 1β (IL-1β) are also been studied as biomarkers for PD [14], [15].