BDNF and Parkinson disease: 16 KEGG pathway terms were identified in this group, including Oxidative phosphorylation, Parkinson’s disease, Non-alcoholic fatty liver disease (NAFLD), Renal cell carcinoma, Alzheimer’s disease, Huntington’s disease, Leukocyte transendothelial migration, Neurotrophin signaling pathway, Chemokine signaling pathway, Focal adhesion, Rap1 signaling pathway, Ras signaling pathway, MAPK signaling pathway, Pancreatic secretion and Metabolic pathways.