24 March 2011

Novel psychiatric drugs aimed at gut bacteria

by Kate Melville

Communication between the bacteria in our gut and our brain plays an important role in the development of psychiatric illness, say McMaster University researchers who are investigating how new psychiatric drugs might directly target intestinal flora.

McMaster neuroscientist Jane Foster contends that this brain-bacteria "cross-talk" plays an important role in the development of psychiatric illness, intestinal diseases and probably other health problems such as obesity. Foster's work adds to a growing body of research linking inflammation and immune system dysfunction to mental illness.

Her research, published in Neurogastroenterology and Motility, shows that gut bacteria influences how the brain is wired for learning and memory. Radical new drugs could take advantage of this connection, she believes. "The wave of the future is full of opportunity as we think about how microbiota or bacteria influence the brain and how the bi-directional communication of the body and the brain influence metabolic disorders, such as obesity and diabetes."

Foster's study showed that the genes linked to learning and memory are altered in germ-free mice and, in particular, they are altered in the hippocampus. "The take-home message is that gut bacteria influences anxiety-like behavior through alterations in the way the brain is wired," she summarized.

"We have a hypothesis in my lab that the state of your immune system and your gut bacteria - which are in constant communication - influences your personality," Foster said. "The idea behind this research is to see if it's possible to develop new therapies which could target the body, free of complications related to getting into the brain. We need novel targets that take a different approach than what is currently on the market for psychiatric illness."

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Source: McMaster University