TABLE 1.

Summary of glycoproteins, corresponding pathologies resulting from glycosylation modifications, and their suggested underlying mechanisms.

Glycoprotein/ Glycomarker	Glycosylation type	Associated disease	Source	Underlying mechanism	References
APP	Bisecting N-GlcNA	Alzheimers meisease	CSF, blood plasma and saliva	Aß accumulation, inflammation, oxidative stress and mitochondrial impairment	Hwang et al., 2010
BACE1	Bisecting N-GlcNA	Alzheimer010pisease	CSF	Aß accumulation, impaired neuronal function	Vanoni et al., 2008; Kizuka et al., 2015
Nicastrin	O-glycosylation	Alzheimertionisease	CSF	Decreased γ-secretase activity and Aß production	Yang et al., 2002
Tau	N-glycosylation O-glycosylation	Alzheimertionisease	CSF and blood plasma	Microtubule disruption, formation of neurofibrillary tangles	Liu et al., 2002; Losev et al., 2021
Acetylcholinesterase (AChE)	N-glycosylation	Alzheimertionisease	CSF and brain tissue	Increase in amyloid, stress, and inflammation	Appleyard and McDonald, 1992; Saez-Valero et al., 1999
Released N-glycans	N-glycosylation	Alzheimertionisease	Brain tissue	Decrease of bisecting and core-fucosylated N-glycans	Gizaw et al., 2016
In situ N-glycan MALDI-imaging	N-glycosylation	Alzheimertionisease	Brain tissue	Hyper-N-glycosylation in the frontal cortex regions	Hawkinson et al., 2022
α-synuclein	O-GlcNAcylated	Parkinsontedgisease	CSF, brain tissue and blood plasma	Synaptic disruption	Vicente Miranda et al., 2017; Levine et al., 2019
TREM2	N-glycosylation	Parkinsontionisease	Blood plasma	Oxidative stress and inflammation	Rayaprolu et al., 2013
DJ-1	–	Parkinson013disease	CSF	Oxidative stress	Advedissian et al., 2016; Sharma et al., 2019
Parkin	–	Parkinson)19risease	CSF	Neurotransmission disruption	Chung et al., 2001; Shimura et al., 2001
Narp (NPTXII)	N-glycosylation	Parkinsontionisease	CSF	Synaptic disruption, neurotransmission impairment, cell death	Moran et al., 2008
Released O-glycans	O-glycosylation	Parkinsontionisease	Brain tissue	Increase of sialylation	Wilkinson et al., 2021