HSPB1 and Parkinson disease: Interestingly, the hub gene HSPB1 was identified to be significantly upregulated in the astrocytes, pericytes, OPCs, and excitatory cells of AD brains, and in endothelial cells of PD and MS brains (Fig. 3A, Additional file 3: Table S2, Additional file 4: Table S3, Additional file 5: Table S4).