In addition, the researchers from the University of California found that the resultant microbiome favoured species with the ability to synthesise biotin, as well as those found to contribute to the inflammation of the gut.
“This report is the first in-depth analysis of microbiome changes associated with BD-induced colitis.”, the scientists specify, highlighting the significance of the findings.
Biology of biotin
Biotin is a water-soluble B vitamin found naturally in some foods and supplements. It plays a vital role in assisting enzymes to break down fats, carbohydrates, and proteins in food as well as helping to regulate signals sent by cells and the activity of genes.
Biotin deficiencies have been increasingly linked with gut disorders such as Inflammatory Bowel disease (IBD) as well as increased gut permeability.
Absorption of the B vitamin occurs via the sodium-dependent multivitamin transporter (SMVT). The researchers in this study previously identified that in BD-induced mouse models, deletion of this biotin transporter or a biotin diet deficiency, lead to features of IBD.
To continue this research and investigate the possible role of the gut microbiome in the demonstrated IBD-like phenotypes, the scientists conducted the present study analysing the stools and intestinal samples of these mice.
For 12 weeks the biotin deficiency group received a diet with no added biotin while the control group's diet was supplemented with biotin.
It was found that after inducing BD in the mice, microbiome dysbiosis occurred to favour opportunistic microbes such as Enterobacter and Helicobacter, with mucus-resistant microbes reducing as a result. It was observed that IBD-like phenotypes then occurred following dysbiosis, suggesting inflammation of the gut.
This is further supported by the discovery of Klebsiella along the GI tract at various points; a genus found to be associated with inflammation. Additionally, it was noted that the induced BD favoured the growth of species able to biosynthesise biotin.
The study findings demonstrate clear microbial shifts in both models of BD in mice, with severe weight loss and chronic inflammation occurring in some models to reflect the phenotypes observed in IBD. These observations provide an interesting insight into possible causes of inflammatory gut conditions and opens future potential for more targeted dietary interventions for its treatment.
“We propose that the lack of biotin availability results in an early composition which favours biotin synthesizers and effective scavengers, and that the week 12 composition may be affected more by the inflammation in the local environment,” the researchers hypothesise. Yet, the use of animal samples does not allow the results to be representative of the human population, and so further RCTs are required using large human samples to conclude a cause-and-effect relationship.
“These findings will facilitate future experiments elucidating the role of the BD-linked microbiota in inflammation and may lead to new therapeutics in the future.”, the report concludes.
“Biotin Deficiency Induces Intestinal Dysbiosis Associated with an Inflammatory Bowel Disease-like Phenotype”
by Julianne C. Yang, Jonathan P. Jacobs, Michael Hwang, Subrata Sabui, Fengting Liang, Hamid M. Said and Jonathan Skupsky.