Location: Immunity and Disease Prevention ResearchTitle: Using metatranscriptomics to determine effects of dietary supplementation with bovine milk oligosaccharides in healthy adults Author
|Westreich, Samuel - University Of California|
|Barile, Daniela - University Of California|
|Salcedo, Jaime - University Of California|
|Mills, David - University Of California|
|Smilowitz, Jennifer - University Of California|
|Korf, Ian - University Of California|
Submitted to: Experimental Biology
Publication Type: Abstract Only
Publication Acceptance Date: 4/22/2017
Publication Date: 4/22/2017
Citation: Westreich, S.T., Barile, D., Salcedo, J., Mills, D.A., Smilowitz, J.T., Korf, I., Lemay, D.G. 2017. Using metatranscriptomics to determine effects of dietary supplementation with bovine milk oligosaccharides in healthy adults. Experimental Biology. 31/940.
Technical Abstract: The study of human milk has revealed the presence of complex human milk oligosaccharide (HMO) molecules, believed to help encourage formation and development of the infant’s gut microbiome. HMOs function as prebiotics for beneficial bacteria, block attachment to pathogens, and interact directly with intestinal cells. Many bovine milk oligosaccharides (BMOs) are structurally analogous to HMOs and can be obtained from whey streams currently discarded as waste. In a prior study, we fed BMOs to healthy adults for the first time to determine safety and tolerability, and found that they did not cause more bloating or gas than a placebo, which suggests that BMOs may be fermented more slowly than other prebiotics. Using 16S sequencing, we also found that fecal microbial populations did not change significantly. It is possible for the functional activity of a microbial population to change without overall abundances changing. We therefore investigated the activity of all gut microbes in vivo simultaneously in a subset of these humans (n=6) fed BMOs. RNA was extracted from RNApreserved stool and libraries were prepared and sequenced to yield a minimum of 40 million reads per subject. Intraindividual bacterial transcriptional profiles appeared more similar to each other. However, differential abundance analysis revealed a small, but significant (p < 3.23e41), increase in overall Bacteroides transcriptional activity in response to the BMO supplement. Specific functions of Bacteroides species are being further investigated. In conclusion, our results demonstrate that it is possible for gut microbe populations to remain stable while their functional activities change in response to diet, emphasizing the need for a metatranscriptomebased approach in future studies.