Defining Alzheimer’s\nDisease through Proteomic\nCSF Profiling

Alzheimer disease (AD) is the main cause of dementia,\nand its complexity\nis not yet completely understood. Proteomic profiles can provide useful\ninformation to explore the pathways involved and the heterogeneity\namong AD patients. A proteomic analysis was performed in cerebrospinal\nfluid (CSF) samples from mild cognitive impairment due to AD (MCI-AD)\nand control individuals; both groups were classified by amyloid β42/amyloid\nβ40 levels in CSF (data available in BioStudies database (S-BSST1456)).\nThe analysis based on PLS regression and volcano plot identified 7\nproteins (FOLR2, PPP3CA, SMOC2, STMN1, TAGLN3, TMEM132B, and UCHL1)\nmainly related to protein phosphorylation, structure maintenance,\ninflammation, and protein degradation. Enrichment analysis revealed\nthe involvement of different biological processes related to neuronal\nmechanisms and synapses, lipid and carbohydrate metabolism, immune\nsystem and inflammation, vascular, hormones, and response to stimuli,\nand cell signaling and adhesion. In addition, the proteomic profile\nshowed some association with the levels of AD biomarkers in CSF. Regarding\nthe subtypes, two MCI-AD subgroups were identified: one could be related\nto synapsis and neuronal functions and the other to innate immunity.\nThe study of the proteomic profile in the CSF of AD patients reflects\nthe heterogeneity of biochemical pathways involved in AD.