Gut feeling: The link between bacteria and brain function

Bugs as drugs. The study “identified several groups of bacteria that co-varied with human depression and quality of life across populations.”

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Yesterday, Nature Microbiology added one more thing to the ever-growing list of correlative factors linked to clinical depression.

The strength of the study survives on two bacterial genera, Coprococcus and Dialister, both said to be depleted in sufferers of depression, irrespective of the treatment they’re on. The idea that gut microbial metabolites bear the potential to impact brain functionality isn’t a novel one in the biology community, but studies had hitherto mostly been conducted on animals.  The findings, published on February 5th, are consistent with one enacted on an independent group comprised of 1,063 individuals.

“In our population-level study, we identified several groups of bacteria that co-varied with human depression and quality of life across populations,” States Professor Raes, who also led the research that ushered these developments closer to some light.

There is a wide range of gut bacteria that possess the ability to form neuroactive compounds. Depletion of the aforementioned Coprococcus and Dialister, (micro groups noted for their anti-inflammatory properties)  occurred much more frequently in those with mood disorders.

Neuer-inflammation has been independently linked to depression in the past, so even though official experimentation still needs to be done to confirm these findings, the road is promising.

As previously stated by myself and those much more qualified, the psychiatric tools currently at our disposal are still fairly clumsy. Too many of the methods used to treat psychosis come with potentially disastrous side effects (like surging suicidal ideations for one). A treatment method that attacks the “silent killer” with more tact and precision is desperately needed. “I really think there is a future in this – using cocktails of human-derived bacteria as treatment. Bugs as drugs, as they say,” says Raes.

Zeroing in on the exact link between the mind and the soma is already birthing inspiring results. The microbial community residing in our bodies have been found to be behind disorders such as dementia, Parkinson’s and autism, though when neuroscientist Dr. John Cryan initially introduced the concept he was met with a fair share of incredulity.

An experiment performed on mice soon after Dr. Cryan’s hypothesis presented tangible results – just the slightest alteration of microbiome gave way to beneficial changes. The antibiotics administered killed off a majority of the gut bacteria found in the subjects thus reducing the protein clumps typically employed by dementia.

CW Headley|is a reporter for Ladders and can be reached at cheadley@theladders.com.