Research Reveals How Prozac Triggers New Brain Cell Growth
The researchers decided to look at how the use of selective serotonin reuptake inhibitor (SSRI) antidepressants — the widely used class of drugs that includes Celexa, Paxil, Prozac and Zoloft — might spur brain cell growth. To do so, they tracked the way in which stem cells — undifferentiated cells that can grow into specialized cells — became neurons in a special mouse model given the antidepressant Prozac (fluoxetine).
"What has been known for 20, 30 years is that Prozac increases the level of serotonin [a neurotransmitter associated with good mood.]" But what wasn't known was why Prozac takes three or four weeks to start working.
"Stem cells in the brain go through several steps before they become neurons," Enikolopov said. Examining the cascade of events, his team found that "cells which are born from the stem cells, called amplifying progenitors, are the cells being targeted by Prozac," he said. According to Enikolopov, Prozac zeroes in on these amplifying progenitors and increases their numbers. Within three to four weeks, his team noticed an increased number of mature neurons.