In a study published in the journal Nature Medicine, a team of researchers led by Dr. Gustavo Turecki, a psychiatrist at the Douglas Institute and a professor at McGill University, discovered that the levels of a tiny molecule — miR-1202 — may provide a marker for depression. It also may help detect those patients who are most likely to respond to antidepressants.
“Using samples from the Douglas Bell-Canada Brain Bank, we examined brain tissues from individuals who were depressed and compared them with brain tissues from psychiatrically healthy individuals,” said Turecki.
The researchers discovered that a microRNA, miR-1202, regulates an important receptor of the neurotransmitter glutamate, he noted.
The research team conducted a number of experiments that showed that antidepressants change the levels of this microRNA.
“In our clinical trials with living depressed individuals treated with citalopram, a commonly prescribed antidepressant, we found lower levels in depressed individuals compared to the non-depressed individuals before treatment,” said Turecki. “Clearly, microRNA miR-1202 increased as the treatment worked and individuals no longer felt depressed.”
He noted that while antidepressants are “clearly effective, there is variability in how individuals respond to antidepressant treatment.”
“We found that miR-1202 is different in individuals with depression and, particularly, among those patients who eventually will respond to antidepressant treatment,” he said.
This discovery may provide “a potential target for the development of new and more effective antidepressant treatments,” he concluded.
Source: McGill University