Various proteins including Neutrophil gelatinase-associated lipocalin (LCN2), progranulin (GRN), glia fibrillary acidic protein (GFAP), and TMEM106B have been identified in the cerebrospinal fluid of patients with AD and other types of dementia, such as amyotrophic lateral sclerosis, frontotemporal, dementia, and Parkinson’s disease, and are correlated with reactive astrocyte pathology [152,153]. Here, GRN is linked to Parkinson disease.