More importantly, compared with the MPTP group, Iba-1+ microglia and GFAP+ astrocytes were activated more significantly in the striatum of the TMAO + MPTP group (Figure 4A–D), indicating that TMAO significantly aggravated the neuroinflammation mediated by the microglia and astrocytes in the striatum of the PD mice. Here, AIF1 is linked to Parkinson disease.