AIF1 and Parkinson disease: Notably, the PD + BoNT group also showed a reduction in the number of Iba-1 positive microglial cells compared to the PD group (Control: 28 ± 2; BoNT: 19 ± 1; PD: 42 ± 2; PD + B oNT: 34 ± 1, *** p < 0.0001).