Psychobiotics: The Next Big Thing?

IPA AdminFrom The Gut

Stressed or depressed? Before popping that pill, consider this: probiotics may soothe you just as well, with no bad side effects.

Studies—often out of labs in Ireland— investigating the ability of probiotics to affect mood are establishing a clear connection between the gut and brain. It began when researchers observed a link between irritable bowel syndrome (IBS) and depression. IBS is usually entangled with psychiatric issues, unexplained symptoms, and functional syndromes in other organ systems. It was once thought that psychiatric symptoms were inherent in the personality type which contracted the gut problem. Later evidence however suggests that the disorder also directly affects the biology linking the gut with the brain.

Now research points to a role for probiotics in treating the mood changes. One study published in Neuroscience journal used the probiotic Bifidobacterium infantis with rats which were then placed in stressful situations. Probiotic treatment lead to normalization of the immune response, reversal of behavioral deficits, and restoration of hormone concentrations in the brainstem.

Also bacteria in your gut may relieve anxiety and stress. In a report in Proceedings of the National Academy of Sciences, researchers fed mice a broth laced with a strain of Lactobacillus rhamnosus. The results: the mice were less likely to be anxious or stressed and also produced less of the stress hormone corticosterone than control mice that drank a bacteria-free broth.

The scientists thought that the gut bacteria normalized the expression of important neurotransmitters in the brain that would naturally be turned up or turned down when animals become stressed or anxious. They looked at the neurotransmitter GABA, the main calming and inhibitory neurotransmitter in the brain.

A while back, researcher John Cryan discussed with National Public Radio how the gut influences the brain, and whether the same might hold true in humans:

 “And what we found was that this bacteria was able to affect the receptors, which are the proteins in the brain that signal the chemicals, so they affected the levels of these receptors…. But it is one of these things that we were quite surprised at, that we were able to get such a pronounced effect and similar effects as if the animals had been given some pharmaceutical agents that are used to treat anxiety and depression.”

Cryan continued: “The effects on behavior were very similar to what we would see if we’d given these mice an acute injection of valium, yeah.”

“… what’s really neat about this and what’s important to reinforce, as well, is that the mechanism that we’re showing, in terms of what it’s doing to the brain and brain chemistry, is the same as what the pharmaceuticals are doing. So it’s not undermining the actual biology theories underlying anxiety or depression in any sense. It’s just showing that we can modulate them by maintaining good digestive health.”

Psychobiotics are born.

Cryan and colleagues in Cork, Ireland defined them thus:

” a live organism that, when ingested in adequate amounts, produces a health benefit in patients suffering from psychiatric illness.”

Now the authors believe that the psychobiotics produce compounds which impact neural function: gamma-aminobutyric acid (GABA), serotonin, catecholamines and acetylcholine are thought to be among them.

When activated in the intestines, these neurotransmitters may trigger a river of change along the gut-brain axis.

Because many millions are choosing medications for anxiety, depression and other psychological disorders, alternative treatments such as psychobiotics will be most welcome.