Zarei, I. | bioRxiv Science

bioRxiv2021

Tissue-wide metabolomics reveals wide impact of gut microbiota on mice metabolite composition

The essential role of gut microbiota in health and disease is well-recognized, but the biochemical details underling beneficial impact remain largely undefined. Dysbiosis of gut bacteria results in the alteration of certain microbial and host metabolites, and identifying these markers could enhance the early detection of certain diseases. We report LC-MS based non-targeted metabolic profiling to demonstrate a large effect of gut microbiota on mammalian tissue metabolites. It was hypothesized that gut microbiota influences the overall biochemistry of the host metabolome and this effect is tissue-specific. Thirteen different tissues from germ-free and conventional mice were selected and their metabolic differences were analyzed. Our study demonstrated a large effect of the microbiome on mammalian biochemistry at different tissue levels and resulted in significant modulation of metabolites from multiple metabolic pathway (p [≤] 0.05). A vast metabolic response of host to metabolites generated by the microbiota was observed, Hundreds of molecular features were detected exclusively in one mouse group, with the majority of these being unique to specific tissue, suggesting direct impact gut microbiota on host metabolism.

microbiology↗

bioRxiv2019

Rice bran supplementation modulates growth, microbiome and metabolome in weaning infants: a clinical trial in Nicaragua and Mali

Rice bran supplementation provides nutrients, prebiotics and phytochemicals that enhance gut immunity, reduce enteric pathogens in mice and diarrhea in neonatal pigs, and warranted attention for improvement of environmental enteric dysfunction (EED) in children at risk. EED is a condition that drives childhood stunting via intestinal dysbiosis and impaired nutrient metabolism. This study investigated effects of rice bran supplementation on growth, EED biomarkers, gut microbiome and metabolome in weaning infants from 6 to 12 months old in Nicaragua and Mali. Healthy infants were randomized to a control group or rice bran group that received daily supplementation at increasing doses each month. Stool microbiomes were characterized using 16S rDNA amplicon sequencing. Stool metabolomes were analyzed using ultra-high-performance liquid-chromatography tandem mass-spectrometry. Statistical comparisons were completed at 6, 8, and 12 months of age. Daily consumption of rice bran was safe and feasible for infant growth, decreasing alpha-1 antitrypsin levels, and modulating gut microbiome and metabolome when compared to control. Rice bran merits investigation as a practical intervention strategy that could decrease EED prevalence and risk for children from low- and middle-income countries where rice is grown as a staple food, and bran is used as animal feed or wasted. One Sentence SummaryDietary rice bran supplementation during infant weaning from 6-12 months of age improved growth outcomes, modulated environmental enteric dysfunction biomarkers, and supported metabolism by the gut microbiome. The authors declare no competing financial or non financial interests to disclose as defined by Nature Research. There are also no other interests that might be perceived to influence the results and/or discussion reported in this paper. Correspondence and requests for materials should be addressed to Dr. Elizabeth Ryan (e.p.ryan@colostate.edu).

clinical trials↗