Heligmosomoides polygyrus is a natural intestinal helminth parasite of mice, which is widely used as a model of chronic small intestinal helminth infection. While it is known that infection with H. polygyrus alters the composition of the host’s bacterial microbiota, the functional implications of this alteration are unclear. We investigated the impact of H. polygyrus infection on short-chain fatty acid (SCFA) levels in the mouse intestine and sera. We found that helminth infection resulted in significantly upregulated levels of the branched SCFA isovaleric acid, exclusively at the proximal end of the small intestine, which is the site of H. polygyrus colonization. We next set out to test the hypothesis that elevating local levels of isovaleric acid was a strategy used by H. polygyrus to promote its own survival. To test this, we supplemented the drinking water of mice with isovalerate during H. polygyrus infection and examined whether this improved helminth fecundity or chronicity. We did not find that isovaleric acid supplementation affected chronicity, however, we found that it did promote helminth fecundity, as measured by helminth egg output in the feces of mice. Through antibiotic-treatment of helminth-infected mice, we found that the bacterial microbiota were required in order to support elevated levels of isovaleric acid in the small intestine during helminth infection. Overall, our data suggests that during H. polygyrus infection there is a microbiota-dependent increase in the local, small intestinal production of isovaleric acid, and this supports helminth fecundity in the murine host.

Helminth infection-induced changes to the small intestinal metabolome can promote helminth fecundity

The gastrointestinal tract is amongst the most densely populated ecosystems on earth, home to an abundant and diverse collection of microbial species, not just bacteria but also Archaea, viruses, fungi etc. Significant interest in this area has been sparked in recent years by an appreciation of the importance of the gut microbiota in the health of the host, and this has led to the microbiome of humans and animals being investigated in depth. Studies have drawn links between host nutrition, the gut microbiota and metabolic and immune functions, which in consequence affect physiology.



The first investigations of the structure of the microbiota were culture-based, however the introduction of sequencing technologies such as Sanger sequencing and subsequent development of 454 sequencing and metagenomics approaches have become the mainstay of microbiota studies. The creation of reference databases and analysis software has provided invaluable tools for assigning taxonomy to generated data. Great progress in characterising the structure of the microbiome recently has paved the way for ongoing and future studies on the functional interactions between the microbiota and the host. Studies on the function of the microbiota are critical in understanding the role of the microbiota in human homeostasis and disease pathogenesis.



The conference will be presenting the latest advancements in gut microbiome and health research. It will bring together experts who are driving technological advancements and striving to understand how nutrition impacts gut microbiome and the interactions between gut microbiome and health.



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Recordings of the conference will be available until 13 April 2021.