Fig. 8

MPTP injection could induce microglial activation and neuroinflammation in the SNpc of MPTP-treated mice. The mice received one intraperitoneal injection of MPTP-HCl per day for five consecutive days, whereas the control mice received saline injections. Then, the mice were decapitated, and the midbrains were obtained at different time points after MPTP intoxication as follows: 0 (immediately after the last MPTP injection), 1, 7, and 21 days after the last MPTP injection. Immunohistochemical analysis was performed to analyse the Iba1 expression (a). The total number of Iba1⁺ cells was counted after MPTP injection (b). The scale bar represents 100 μm. A representative confocal image showing the expression of MEKK3 and Iba1⁺ is presented (c), and graphical representations of MEKK3 (d) and Iba1⁺ (e) intensity after MPTP injection are also shown. Green: anti-MEKK3; red: anti-Iba1; blue: DAPI. The scale bar represents 100 μm. RT-qPCR confirmed the expression levels of IL-6 (f), TNF-α (g), and IL-10 (h) after MPTP injection, and the fold change was normalised by GAPDH levels. Data are normalised to those in saline controls and presented as the mean ± SD of three independent experiments. The fold change is statistically significant. *P < 0.05, **P < 0.01, ***P < 0.001