Depression and chronic stress can cause a decrease in brain volume due to a loss of neural connections in it, according to a study published in the journal Nature Medicine . Responsible for this loss is the transcription factor GATA1, a kind of ‘genetic switch’ that is activated in the brains of people with depression.
GATA1 represses the expression of at least five genes necessary to form the synaptic connections between neurons. The loss of these connections causes alterations in emotional and cognitive processes, and also contributes to the loss of brain mass in the prefrontal cortex.
To reach these conclusions, the team of researchers, from Yale University, analyzed brain tissue donated by patients with and without depression, finding that people who had been depressed had lower expression of genes related to neural connections . A second experiment showed that when factor GATA1 was activated in the brain of laboratory mice, they showed symptoms of depression.
The authors hope that knowledge of the functions of GATA1 may one day help identify people at high risk for depression or with increased sensitivity to stress. “We hope that, by improving synaptic connections, either with new drugs, or with psychotherapy, we can develop more effective antidepressant therapies,” explained Ronald Duman, one of the authors.
