Neuron-derived extracellular vesicles enriched from plasma show altered size and miRNA cargo as a function of antidepressant drug response

• Published in: Molecular psychiatry Vol. 26; no. 12; pp. 7417 - 7424
• Main Authors: Saeedi, Saumeh, Nagy, Corina, Ibrahim, Pascal, Théroux, Jean-Francois, Wakid, Marina, Fiori, Laura M., Yang, Jennie, Rotzinger, Susan, Foster, Jane A., Mechawar, Naguib, Kennedy, Sidney H., Turecki, Gustavo
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.12.2021; Nature Publishing Group
• Subjects: 38; 38/91; 631/1647; 631/378; 692/53/2422; 692/699/476/1414; Antidepressants; Antidepressive Agents - metabolism; Antidepressive Agents - pharmacology; Antidepressive Agents - therapeutic use; Behavioral Sciences; Biological Psychology; Blood plasma; Cell lines; Cell organelles; Citalopram; Drug therapy; Extracellular vesicles; Extracellular Vesicles - genetics; Extracellular Vesicles - metabolism; Health aspects; Humans; Immunoprecipitation; Major depressive disorder; Medicine; Medicine & Public Health; MicroRNA; MicroRNAs; MicroRNAs - metabolism; miRNA; Neurons; Neurons - metabolism; Neurosciences; Patient outcomes; Patients; Pharmacotherapy; Physiological aspects; Plasma; Psychiatry; Canada
• ISSN: 1359-4184; 1476-5578
• DOI: 10.1038/s41380-021-01255-2

Previous work has demonstrated that microRNAs (miRNAs) change as a function of antidepressant treatment (ADT) response. However, it is unclear how representative these peripherally detected miRNA changes are to those occurring in the brain. This study aimed to use peripherally extracted neuron-derived extracellular vesicles (NDEV) to circumvent these limitations and investigate neuronal miRNA changes associated with antidepressant response. Samples were collected at two time points (baseline and after 8 weeks of follow-up) from depressed patients who responded ( N  = 20) and did not respond ( N  = 20) to escitalopram treatment, as well as controls ( N  = 20). Total extracellular vesicles (EVs) were extracted from plasma, and then further enriched for NDEV by immunoprecipitation with L1CAM. EVs and NDEVs were characterized, and NDEV miRNA cargo was extracted and sequenced. Subsequently, studies in cell lines and postmortem tissue were conducted. Characterization of NDEVs revealed that they were smaller than other EVs isolated from plasma ( p  < 0.0001), had brain-specific neuronal markers, and contained miRNAs enriched for brain functions ( p  < 0.0001) Furthermore, NDEVs from depressed patients were smaller than controls ( p  < 0.05), and NDEV size increased with ADT response ( p  < 0.01). Finally, changes in NDEV cargo, specifically changes in miR-21-5p, miR-30d-5p, and miR-486-5p together ( p  < 0.01), were associated with ADT response. Targets of these three miRNAs were altered in brain tissue from depressed individuals ( p  < 0.05). Together, this study indicates that changes in peripherally isolated NDEV can act as both a clinically accessible and informative biomarker of ADT response specifically through size and cargo.