The answers to questions like these can be found in Jill Venton’s lab at University of Virginia. She chairs the Department of Chemistry and is an expert in the juices that get brains flowing.
Ten years ago, her group was the first to insert tiny sensors into fruit fly brains to track the work of individual chemical molecules. Now, the research she oversees is illuminating how certain drugs might work to fight depression in the darkness of the human brain.
Among other molecules, the lab has begun studying the path of serotonin. The chemical is an important messenger within the brain and throughout the body. Vital functions such as mood, sleep and appetite (both for food and amore) are thought to rely heavily on our ability to self-regulate the stuff.
When our brains don’t seem to be able, doctors often turn to selective serotonin reuptake inhibitors, or SSRIs. The drugs go by brand names such as Prozac and Lexapro, and they’re most often prescribed for anxiety and depression.
“The protein in the brain that the SSRI works on is called ‘the serotonin transporter,’” Venton said. “The transporter’s basic job is to take serotonin back up into the nerve cell. The way the SSRI works is, it says, ‘Don’t clear the serotonin anymore. Let it stay out there.’ Because when it’s out there in the brain, it can do more signaling.”
Upward of 13% of the adult population, or more than 30 million Americans, take SSRIs.
“There’s a lot of controversy right now in the field over serotonin,” Venton said. “For years, we’ve been giving these drugs that attack the serotonin system in hopes that they raise your levels. But is the serotonin level really low in depressed patients? We don’t know, and we don’t have a really good way to measure that for a human.”
In the search for answers, enter the once pesky fruit fly.