Scientists from McGill University and the Douglas Institute have found new clues about what happens in the brain during depression.
This major discovery could help improve treatments for one of the most common and serious mental health problems in the world.
Depression affects over 264 million people globally and is one of the top causes of disability. People with depression often struggle with low mood, fatigue, and difficulty enjoying life.
While many treatments exist, not all of them work well for everyone. That’s why scientists are working hard to understand exactly what causes depression in the brain.
In this new study, researchers looked at brain tissue from people who had depression and compared it to those who didn’t. They used advanced tools to examine individual brain cells. This allowed them to find out which cells were behaving differently in people with depression.
The study was possible because of a rare brain tissue collection at the Douglas-Bell Canada Brain Bank. This collection includes brain donations from people who had psychiatric conditions, which is very rare. The researchers used this resource to study brain tissue from 100 people—59 who had depression and 41 who didn’t.
They used a special method called single-cell genomic analysis to look closely at the RNA and DNA inside thousands of brain cells. This helped them discover that two specific types of cells were affected in people with depression.
The first type is a group of excitatory neurons. These brain cells help control mood and stress. The second type is a kind of microglia, which are immune cells in the brain. Microglia help manage inflammation.
In people with depression, both of these cell types showed changes in how certain genes were turned on or off. This suggests that their normal function might be disrupted.
This is the first time scientists have been able to clearly see how these two types of cells are changed in depression. Dr. Gustavo Turecki, one of the lead researchers, said that this gives us a clearer picture of how depression affects the brain at the cellular level.
It also helps move away from the old idea that depression is just about emotions. Instead, the study shows that depression involves real, physical changes in the brain.
By focusing on the exact brain cells that are involved, scientists now have a better starting point for designing new treatments. These treatments could be more targeted and possibly work better for people who don’t respond to current options.
The research team plans to keep studying how these changes affect brain function and how they might be reversed. This could lead to better ways to help people with depression in the future.
The study, led by Anjali Chawla and Dr. Gustavo Turecki, was published in the journal Nature Genetics under the title “Single-nucleus chromatin accessibility profiling identifies cell types and functional variants contributing to major depression.”
If you care about mental health, please read studies about Middle-aged women with no kids may have this mental issue and findings of scientists find a cause of mental illnesses induced by childhood abuse.
For more about mental health, please read studies about Frequent painkiller use linked to mental health risks in these people and findings of Common depression drugs may offer new treatment for bipolar disorder.
The study is published in Nature Genetics.
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