“…the current generation is facing an epidemic of diseases associated with dysregulated inflammation…” says Dr. P’ng Loke and his colleague, Dr. Yvonne Lim, in an article[i] I just finished on the interactions of the microbiota and helminths. This is, without a doubt, one of my favorite papers: so many fantastic pieces of information in it!
A few really great take-away points for you to know:
- By limiting out-of-control inflammatory responses triggered by the intestinal bacteria, helminths may be important for maintaining the health of the mucosal lining of the intestine. Knocking out the immune response to helminths in mice can cause sepsis by compromising the intestinal wall, leading to the leakage of gut bacteria into the body.
- The presence of helminths may be “…especially important in early life or even in pregnant mothers.” The article describes a double blinded, placebo controlled study on 2507 pregnant women in Africa to test different anti-helminth drugs. Surprisingly, the researchers found that the incidence of eczema increased with anti-helminth treatment.
“These results suggest that deworming during pregnancy might promote allergic disease in offspring. This large randomized study provides clinical evidence that helminth infection during pregnancy may protect children from immune dysregulation, as well as indicating that helminth infection during pregnancy does not have a negative effect on the offspring.”
HOLY COW! That is huge! Imagine how much healthier the next generation of children might be if we could convince future mothers to enrich their biomes before pregnancy.
- The metabolites produce by the gut microbiota are not restricted to just the intestinal tract, but have effects on peripheral tissues. (Read my post on the metabolome.) To illustrate the importance of this concept, the authors cite a mouse study in which the diet was supplemented with dietary fiber. This led to an increase in short chain fatty acids (SCFA), as the gut microbiota metabolized the fiber. This increase in SCFA protected mice from allergic inflammation. The authors go on to explain that SCFAs are already known to regulate intestinal inflammation and to boost regulatory t-cells (the off switch to the pro-inflammatory system.) “These findings provide a potential mechanistic link between alterations to our modern diet (low fiber high fat) and increased susceptibility to inflammatory diseases.” (Read my post about eating your fiber.)
- While diet then may well explain some of the differences between the developing and developed world, in terms of the richness of the microbiota, the authors remind us that, “…there is growing evidence that helminth infections may also have a substantial impact on the human microbiota.” (See my post on the microbiome-macrobiome connection.) The authors performed a cross-sectional study on 51 people from two Malaysian villages. The found that “…the helminth-colonized individuals among these villagers had great species richness…”
The authors state in their conclusion that bacterial communities do have the tendency to stabilize and prove resistant to change. However, it is possible that we can use helminths to drive our microbiomes toward species that are “…more immune regulatory.” What’s not to love about that?!
[i] Loke, P, Lim, YAL. Helminths and the microbiota: parts of the hygiene hypothesis. Parasite Immunology. 2015; 37(6):314-323.