Proteomics of the astrocyte secretome reveals changes in their response to soluble oligomeric Aβ

• Published in: Journal of neurochemistry 2023-07, Vol.166 (2), p.346-366
• Main Authors: Matafora, Vittoria, Gorb, Alena, Yang, Fangjia, Noble, Wendy, Bachi, Angela, Perez‐Nievas, Beatriz Gomez, Jimenez‐Sanchez, Maria
• Format: Article
• Language: English
• Subjects: Alzheimer Disease - metabolism; Alzheimer's disease; Amyloid beta-Peptides - metabolism; Amyloid beta-Protein Precursor - metabolism; Amyloid precursor protein; Astrocytes; Astrocytes - metabolism; Biomarkers; Brain; Cerebrospinal fluid; Cytoskeleton; Extracellular matrix; Humans; Neurodegenerative diseases; Oligomers; Original; ORIGINAL ARTICLES; Oxidative stress; Proteins; Proteomics; Secretion; Secretome; Senile plaques; Transcriptomics; Transgenes; β-Amyloid
• ISSN: 0022-3042; 1471-4159
• DOI: 10.1111/jnc.15875

Astrocytes associate with amyloid plaques in Alzheimer's disease (AD). Astrocytes react to changes in the brain environment, including increasing concentrations of amyloid‐β (Aβ). However, the precise response of astrocytes to soluble small Aβ oligomers at concentrations similar to those present in the human brain has not been addressed. In this study, we exposed astrocytes to media from neurons that express the human amyloid precursor protein (APP) transgene with the double Swedish mutation (APPSwe), and which contains APP‐derived fragments, including soluble human Aβ oligomers. We then used proteomics to investigate changes in the astrocyte secretome. Our data show dysregulated secretion of astrocytic proteins involved in the extracellular matrix and cytoskeletal organization and increase secretion of proteins involved in oxidative stress responses and those with chaperone activity. Several of these proteins have been identified in previous transcriptomic and proteomic studies using brain tissue from human AD and cerebrospinal fluid (CSF). Our work highlights the relevance of studying astrocyte secretion to understand the brain response to AD pathology and the potential use of these proteins as biomarkers for the disease. Astrocytes react to Aβ plaques in AD, however, the precise response of astrocytes to amyloid‐β (Aβ) remains uncertain. Here, we undertook a proteomic analysis of the astrocyte secretome in response to media containing Aβ oligomers. This study revealed differential secretion of proteins involved in the extracellular matrix and cytoskeletal organization, changes in the response to oxidative stress, and increased secretion of proteins with chaperone activity.