Elevated levels of several of inflammatory mediators (TNFα, NO, PGE2, IL1β, IL6) and oxidized biomolecules (4-hydroxynonenal, oxidative cholesterol metabolites, 8-oxoG) are found in the cerebrospinal fluid of PD patients, as well as in postmortem samples of SN of PD patients [190,191,192]. Here, IL6 is linked to Parkinson disease.