Gut-targeted antidepressants: A novel approach to battling depression and anxiety

Most of us have experienced the effects of moods and emotions on our gastrointestinal tract, from "butterflies" in the stomach caused by nervousness to a loss of appetite when we're feeling blue.

A new study in animals suggests that targeting antidepressant medications to cells in the gut could not only be an effective treatment of mood disorders like depression and anxiety but may also cause fewer cognitive, gastrointestinal, and behavioral side effects for patients and their children than current treatments.

Mark Ansorge, associate professor of clinical neurobiology, Columbia University Vagelos College of Physicians and SurgeonsBut not treating a pregnant person's depression also comes with risks to their children. An SSRI that selectively raises serotonin in the intestine could be a better alternative."

How do SSRI antidepressants work?

SSRIs boost serotonin signaling, and the drug's effects on mood are thought to stem from increased serotonin signaling in the brain, where serotonin helps to relay messages.

The researchers tested this possibility in mice using a combination of genetic engineering, surgery, and pharmaceuticals.

Increasing intestinal serotonin reduces anxiety, depressive behaviors in mice

"Based on what we know about interactions between the brain and gut, we expected to see some effect. But to see enhanced serotonin signaling in the gut epithelium produce such robust antidepressant and anxiety-relieving effects without noticeable side effects was surprising even to us," Ansorge says.

"There may be an advantage to targeting antidepressants selectively to the gut epithelium," adds Margolis. "Systemic treatment may not be necessary for eliciting the drugs' benefits."

A better antidepressant option during pregnancy?

The new study adds to the evidence that in utero exposure to serotonin-targeting antidepressants has negative effects on children. The researchers looked at more than 400 mothers and babies and found that children exposed to such antidepressants were 3 times more likely to develop constipation in their first year of life.

Ansorge and Margolis caution that pregnant people currently taking SSRIs should not discontinue their treatment based on these and other findings. "Maternal depression and anxiety can have many unwanted effects on fetal and child development and must thus be treated and monitored adequately to the benefit of both mother and child," says Ansorge.

"Our findings indicate that we may be able to treat a mother's depression or anxiety effectively without exposing the child," Ansorge says, "and we are working on drug delivery technology that will hopefully help us achieve that."

Source:

Columbia University Irving Medical Center

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