(A) Dose-response curve for inhibition of ATP-induced NLRP3 inflammasome activation by MCC950 in LPS-primed microglia (n=3–4). (B) Fibrillar α-synuclein (α-Syn)-mediated microglial IL-1β secretion in the presence or absence of MCC950 (100 nM) (n=8–11). (C) Western blots and (D) densitometric analysis for cleaved caspase-1 (p20), cleaved IL-1β (p17) and ASC in the supernatants of α-synuclein-activated microglia co-treated with MCC950 (n=3). (E) Western blot and (F) densitometric quantification of oligomeric ASC (both dimers (D) and tetramers (T)) in microglia treated as indicated (n=3). (G) Pharmacokinetics of MCC950 over 24 h in plasma (ng/ml) or perfused mouse brain (ng/g) following oral gavage (20 mg/kg) (n=3–4 mice/time point). The equivalent microglial IC50 of MCC950 (~3 ng/ml) is indicated by the dashed line. (H-J) Western blot and densitometric quantification of cleaved caspase-1 in (H) ipsilateral striatal tissue lysates of α-synuclein PFF-injected mice at 30 days (n=6 mice/group); (I) substantia nigra tissue lysates of 12-week old MitoPark (MP) mice (n=5–7 mice/group); and (J) ipsilateral striatal tissue lysates of 6-OHDA (6-OH) lesioned mice at 7 days (n=9 mice/group). Data shown as mean ± SEM. *P < 0.05, **P < 0.01, ***P < 0.001 by one-way ANOVA with Bonferroni’s post-hoc test (panels F, H-J), or Kruskal-Wallis test with Dunn’s post-hoc test (panels B, D).