Can blood samples help predict how well someone will respond to antidepressant medications?
Original Title:
Neuron-derived extracellular vesicles enriched from plasma show altered size and miRNA cargo as a function of antidepressant drug response
Link: https://pubmed.ncbi.nlm.nih.gov/34385599
Research has shown that certain molecules in the body called microRNAs (miRNAs) can change in response to antidepressant treatment. However, it’s been unclear whether these changes in miRNAs in the bloodstream accurately reflect what’s happening in the brain.
In this study, researchers, Saumeh Saeedi, Gustavo Turecki, and their colleagues aimed to answer this question by examining tiny particles released by brain cells called neuron-derived extracellular vesicles (NDEVs) that circulate in the blood and offer insights into brain-related changes. To start, blood samples were collected from depressed patients who either responded or did not respond to treatment with the antidepressant escitalopram. Blood samples were also collected from individuals without depression to compare differences between groups. The researchers then isolated NDEVs from these samples and analyzed their contents.
The researchers found that NDEVs were smaller than other extracellular vesicles (EVs) in the blood and contained markers specific to brain cells. Additionally, the miRNAs found in NDEVs were linked to specific brain functions. The researchers also noted that the NDEVs from depressed patients were smaller compared to those from non-depressed individuals, and their size increased in response to antidepressant treatment.
Importantly, changes in the miRNAs were associated with how well individuals responded to antidepressant treatment. Specifically, certain miRNAs showed significant changes related to treatment response. These miRNAs also influenced the activity of genes in the brain, suggesting that they may have a potential role in antidepressant response.
Overall, this study suggests that examining changes in NDEVs from blood samples could serve as a useful and accessible way to understand how individuals respond to antidepressant treatment. The findings open up the door for future research into using blood biomarkers to personalize depression treatment and improve outcomes for patients.
Citation: Saeedi S, Nagy C, Ibrahim P, Théroux J-F, Wakid M, Fiori LM, et al. Neuron-derived extracellular vesicles enriched from plasma show altered size and miRNA cargo as a function of antidepressant drug response. Mol Psychiatry 2021;26:7417–24. https://doi.org/10.1038/s41380-021-01255-2