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bioRxiv · 10.1101/2022.06.23.497433

Two unique biological response-modifier glucans beneficially regulating gut microbiota and faecal metabolome in a non-alcoholic steatohepatitis animal model, with potential for applications in human health and disease

Abstract

ObjectiveThe gut microbiome and its metabolites, influenced by age and stress, reflect the metabolism and immune systems health. We assessed the gut microbiota and faecal metabolome in a Stelic Animal Model of non-alcoholic steatohepatitis (NASH). DesignThis model was subjected to the following treatments: reverse osmosis water, AFO-202, N-163, AFO-202+N-163, and telmisartan. Faecal samples were collected at 6 weeks and 9 weeks of age. The gut microbiome was analysed using 16S ribosomal RNA sequence acquired by next-generation sequencing and the faecal metabolome using gas chromatography-mass spectrometry. ResultsThe gut microbial diversity increased greatly in the AFO-202+N-163 group. Post-intervention, the abundance of Firmicutes decreased, while that of Bacteroides increased and was the highest in the AFO-202+N-163 group. The decrease in the Enterobacteria and other Firmicutes abundance and in the Turicibacter and Bilophila abundance was the highest in the AFO-202 and N-163 groups, respectively. The Lactobacillus abundance increased the most in the AFO-202+N-163 group. The faecal metabolites spermidine and tryptophan, beneficial against inflammation and NASH, respectively, were greatly increased in the N-163 group. Succinic acid, beneficial in neurodevelopmental and neurodegenerative diseases, increased in the AFO-202 group. Decrease in fructose was the highest in the AFO-202 group. Leucine and phenylalanine decreased, whereas ornithine, which is beneficial against chronic immune-metabolic-inflammatory pathologies, increased in the AFO-202+N-163 group. ConclusionAFO-202 treatment in mice is beneficial against neurodevelopmental and neurodegenerative diseases and has prophylactic potential against metabolic conditions. N-163 treatment has anti-inflammatory effects against organ fibrosis and neuroinflammatory conditions. In combination, they present anticancer activity. Key messagesO_LIThe influence of gut microbiome on fecal metabolome and their association to several diseases is already known. C_LIO_LIThis study proves the efficacy of 1,3-1,6 beta glucans with pre-biotic potentials, beneficially influencing both gut microbiome and metabolome. C_LIO_LIThese results recommends for an in-depth exploration of relationship among pre-biotics, gut microbiome and gut-multi-organ axes on the fundamentals of disease onset. C_LIO_LIHidden prophylactic and therapeutic solutions to non-contagious diseases with Aureobasidium pullulans produced 1,3-1,6 beta glucans may be unveiled. C_LI

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BibTeXRIS

Preethy, S., Ikewaki, N., Levy, G. A., Raghavan, K., Dedeepiya, V. D., Yamamoto, N., Srinivasan, S., Ranganathan, N., Iwasaki, M., Senthilkumar, R., Abraham, S. J.. 2022-06-25. Two unique biological response-modifier glucans beneficially regulating gut microbiota and faecal metabolome in a non-alcoholic steatohepatitis animal model, with potential for applications in human health and disease. https://doi.org/10.1101/2022.06.23.497433

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