Short-Chain Fatty Acids Modulate Healthy Gut Microbiota Composition and Functional Potential
This study was published by Peterson et. al. in Current Microbiology 2022 at https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8921067/.
The article explores the potential of short-chain fatty acids (SCFAs), produced by human gut microbiota, to modulate the gut microbiome in vitro. Numerous studies have examined the metabolic capacity of human gastrointestinal microbiota to produce short-chain fatty acids and the resulting effects on host physiology. Given the paucity of information on how SCFAs produced by gut bacteria influence community structure and function via cross-feeding, we evaluated the potential of SCFAs to modulate human gut microbiota in vitro. We used anaerobic fecal cultivation in a chemically defined medium supplemented with one of nine SCFAs to determine the effects on the structure of the gut microbial community (16S rRNA sequencing) and the function of the gut microbial community (genome reconstruction analysis).
Regarding the relative abundance of bacterial taxa, every SCFA exhibited a significant and distinct modulatory capacity. Analysis of SCFA-supplemented communities revealed that alterations of closely related phylotypes exhibited coherent changes, with exceptions indicating strain-dependent distinctions in SCFA-induced alterations. We evaluated the functional implications of SCFA-mediated reorganization of fecal communities via genome reconstruction.
We employed anaerobic fecal cultivation in a chemically defined medium supplemented with nine different SCFAs to observe their effects on gut microbial community structure and function. Each SCFA displayed significant and unique modulatory potential, impacting the relative abundance of bacterial taxa. The study also evaluated the functional implications of SCFA-mediated restructuring of fecal communities through genome reconstruction analysis.
The results suggest that SCFAs not only serve as end-products of metabolism but also play a crucial role in cross-feeding, altering the fitness and abundance of specific bacterial taxa. The study identified various bacteria that responded positively or negatively to different SCFAs, with some species showing increased fitness due to SCFA consumption. Some SCFA-supplemented cultures exhibited a decrease in the predicted abundance of SCFA producers, suggesting the existence of an undefined negative feedback mechanism. The data highlight the importance of SCFAs in influencing gut microbiota composition and metabolism, which has implications for identifying potential prebiotics that can promote specific SCFA production for therapeutic benefits.
The article acknowledges that further research is needed to understand the direct and indirect effects of SCFAs on gut microbial communities and to validate the identified SCFA consumers. The significance of these findings lies in the identification of prebiotics that elevate specific SCFAs for therapeutic benefit and in the identification of SCFA consumers as a prominent component of the overall metabolic flux associated with bacterial fermentative processes. In summary, this study sheds light on the complex interactions between SCFAs and gut microbiota, paving the way for potential therapeutic applications in promoting gut health and overall well-being.
REFERENCE
Short-Chain Fatty Acids Modulate Healthy Gut Microbiota Composition and Functional Potential. Peterson CT, Perez Santiago J, Iablokov SN, Chopra D, Rodionov DA, Peterson SN. Curr Microbiol. 2022 Mar 14; 79(5):128. PMID: 35287182; PMCID: PMC8921067. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8921067/
