So many studies have come out recently that are of interest that I had a hard time choosing the winner for today’s post. I finally settled on an article[i] from the journal, Medical Sciences, on the potential use of microbiome manipulation in treating neuropsychiatric disorders, as so many of us, friends and family, are now affected by “mental” illnesses ranging from depression to anxiety disorders to autism.
There was so much in this paper that it’s an almost overwhelming task to select the highlights for this post. I’ll do my best!
First though, I have to tell you what stunned me right off the bat. Did you know that the first paper ever published (in the British Journal of Psychiatry) on the use of “psychobiotics” (probiotic bacteria that have a beneficial effect on psychiatric illness) dates back to 1910?! That is astounding! Over 100 years ago, scientists already recognized the potential, and tested the efficacy, of Lactobacilli in treating depression: “Melancholia…lends itself at once to a dietetic form of treatment.”[ii]
We haven’t made a hell of a lot of progress in the last 109 years, have we?
Ok – back to highlights:
In their conclusion the authors state that we are undergoing a “significant paradigm shift” in the treatment of neuropsychiatric disorders.
Well, of course, the Biome Buzz is on top of every biome news story and following this paradigm shift closely, but on occasion, my timing even astounded me. This morning, the biome headlines are screaming about a new, large scale study looking at microbiota differences between those with and without depression. Uncanny coincidence, right?! Microbiologists in Belgium analyzed the microbiota of 1074 Belgians, 173 of which were diagnosed with depression, and found:
“Two kinds of microbes, Coprococcus and Dialister, were missing from the microbiomes of the depressed subjects, but not from those with a high quality of life. The finding held up when the researchers allowed for factors such as age, sex, or antidepressant use, all of which influence the microbiome…They also found the depressed people had an increase in bacteria implicated in Crohn disease, suggesting inflammation may be at fault.”[iii]
Because microbiota vary from population to population, they also looked at a population of 1064 Dutch people and found those exact same two species missing in the those with depression.
They then tried to figure out what it is about these species that could be causative of depression and compiled a list of 56 substances that gut bacteria produce or breakdown which could affect the nervous system. They found, for example, “…that Coprococcus seems to have a pathway related to dopamine, a key brain signal involved in depression, although they have no evidence how this might protect against depression. The same microbe also makes an anti-inflammatory substance called butyrate, and increased inflammation is implicated in depression.”
While this is not yet proof that the missing species are the cause of the depression, this is still a major step forward toward creating a psychobiotic to treat the illness. And by the way, according to this article from Science Magazine, a clinical trial using fecal microbiota transplant to treat depression is planned at the University of Basel in Switzerland! I have high hopes.
[i] Evrensel, A, Onen Unsalver, B, Ceylan, ME. Therapeutic potential of the microbiome in the treatment of neuropsychiatric disorders. Medical Sciences. 2019:7, 21.
[ii] Phillips, J. The treatment of melancholia by the lactic acid bacillus. J. Mental. Sci. 1910, 56, 422–430.