Scientists have isolated a unique molecular pattern that might one day enable a 'stress vaccine' to exist for real – and they found it hidden inside a bacterium that thrives in dirt.
Mycobacterium vaccae is a non-pathogenic bacterium that lives in soil, and has shown considerable promise in health research;
M, now that a specific child of fat inside M. vaccae could be why exposure to this beneficial bacterium in soil may be good for us.
This work is in the idea of "old friends", a hypothesis that claims humans co-evolved with a bunch of useful microorganisms, and release these in the modern environment has led to an increase in allergic and autoimmune diseases. "The idea is that humans have moved away from farms and an agricultural or hunter-gatherer existence into cities, we have lost contact with organisms served to regulate our immune system and suppress inappropriate inflammation, "says neuroendocrinologist Christopher Lowry.
" That has put us at higher risk of inflammatory disease and stress-related psychiatric disorders. " researching M. Vaccae for years, finding in a previous study that injected mice with a heat-killed preparation of the bacterium prevented the emergence of stress-induced reactions in the animals.
But until now, nobody was sure what was it M. vaccae that could be responsible for such effects.
"One of the burning questions is, essentially, what are the critical components of the bacteria that seem to benefit the host?" Lowry customs The Denver Post
In the new study, the researchers isolated and chemically synthesized a fatty acid called 1
Peroxisome proliferator-activated receptors (PPAR) appear at the molecular level. In doing so, it inhibits inflammation pathways – at least, in experimentally treated mouse immune cells.
"It seems that these bacteria we co-evolved with have a trick up their sleeve," says Lowry.
"When they get taken up by immune cells, they release these lipids that bind to this receptor and shut off the inflammatory cascade. "
A lot more work would need to be done to see if the same effect could be replicated in humans. If the researchers say this discovery could help eventually develop a 'stress vaccine' to help people in high-stress professions that place them at risk of developing post-traumatic stress disorder.
That's still a long way off, as the research stands now. Lowry is rather optimistic however, estimating it might only be 10 to 15 years before such a treatment is available; if he's right, we'll have bugs in the dirt to thank.
"We used to think that microbacteria were an important part of the human microbiome," Lowry customs The Denver Post . 19659004] "The power of nature continues to amaze us as scientists and we look forward to learning more." The findings are reported in Psychopharmacology .