WASHINGTON: Severe depression or chronic stress
can cause your brain to shrink and lead to emotional and cognitive
impairment, a new study has claimed. A team of researchers led by Yale
scientists discovered that one reason for this condition is a single
genetic switch that triggers loss of brain connections in humans and
depression in animal models.
The findings, published in the
journal 'Nature Medicine' , show that the genetic switch known as a
transcription factor represses the expression of several genes that are
necessary for the formation of synaptic connections between brain cells,
which in turn could contribute to loss of brain mass in the prefrontal
cortex of the brain.
"We show that circuits normally involved in emotion , as well as cognition, are disrupted when this single transcription factor is activated ," Duman said.
Scientists analysed tissue of depressed and non-depressed patients donated from a brain bank and looked for different patterns of gene activation. The brains of patients who were in depression exhibited lower levels of expression in genes that are required for function and structure of brain synapses.
Lead author and postdoctoral researcher H J Kang discovered that at least five of these genes could be regulated by a single transcription factor called GATA1
