Immunochemical analysis of brain tissue from patients with PSP showed activation and increased numbers of microglia in the substantia nigra compacta, subthalamic nucleus, pyramidal, and extrapyramidal motor systems, which correlated positively with tau burden, and upregulated expression levels of pro-inflammatory factors such as IL-1β were found in the substantia nigra (Gao et al., 2023). This evidence concerns the gene MAPT and supranuclear palsy, progressive, 1.