Researchers at McGill University and the Douglas Institute have pinpointed two types of brain cells that are altered in individuals with depression, a discovery that could pave the way for targeted treatments.
Published in Nature Genetics, the study analyzed post-mortem brain tissue from the Douglas-Bell Canada Brain Bank, one of the world’s few repositories with donated tissue from people who had psychiatric conditions. Using single-cell genomic techniques, the team examined RNA and DNA from thousands of individual cells, comparing samples from 59 people with depression to 41 without.
The analysis revealed significant gene activity changes in a type of excitatory neuron involved in mood and stress regulation, as well as a subtype of microglia, which manage brain inflammation. These findings indicate that key brain systems may be disrupted in depression.
“This research reinforces what neuroscience has been telling us for years,” said Gustavo Turecki, one of the study’s lead authors. “Depression isn’t just emotional—it reflects real, measurable changes in the brain.”
By identifying the specific cells affected, the study deepens understanding of depression’s biological roots and challenges lingering misconceptions about the disorder. The researchers now plan to investigate how these cellular alterations impact overall brain function and whether targeting them could lead to more effective therapies.
The study, “Single-nucleus chromatin accessibility profiling identifies cell types and functional variants contributing to major depression” by Anjali Chawla, Gustavo Turecki, and colleagues, was funded by the Canadian Institutes of Health Research, Brain Canada Foundation, Fonds de recherche du Québec – Santé, and McGill University’s Healthy Brains, Healthy Lives initiative.
