AUTHOR=Liu Xiao-Chen , Sun Qian , Ji Yan-Chun , Fu Li-Zhen , Wang Zheng-Li , He Yu , Li Lu-Quan 

TITLE=Differences in the Gut Microbiota Composition and Metabolites Associated With Feeding Intolerance in VLBW Infants With a Gestational Age of ≤ 30 Weeks: A Pilot Study

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=12

YEAR=2022

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2022.726322

DOI=10.3389/fcimb.2022.726322

ISSN=2235-2988

ABSTRACT=<sec><title>Objective</title><p>To explore the main variations in gut microbiota compositions, short-chain fatty acids (SCFAs) concentrations and autoinducer-2 (AI-2) levels in very-low-birth-weight (VLBW) infants with feeding intolerance (FI).</p></sec><sec><title>Methods</title><p>Twenty-seven VLBW infants with gestational ages of ≤30 weeks were divided into the FI group (n=14) and feeding tolerance (FT) group (n=13). The gut microbiota composition and SCFAs concentrations and AI-2 levels in feces were detected at 2 and 4 weeks after birth.</p></sec><sec><title>Results</title><p>There was no difference in alpha diversity between the two groups at 2 and 4 weeks after birth (<italic>P</italic>&gt;0.05). Although the <italic>Chao</italic> index decreased (<italic>P</italic>&lt;0.05), there was no difference in the <italic>Shannon</italic> index from 2 weeks to 4 weeks in either the FI or FT group (<italic>P</italic>&gt;0.05). Additionally, there was no difference in beta diversity between the FI and FT groups at 2 weeks (<italic>P</italic>&gt;0.05), but there was a significant difference in beta diversity between the two groups at 4 weeks (<italic>P</italic>&lt;0.05) and a large difference from 2 weeks to 4 weeks in both the FI and FT groups (<italic>P</italic>&lt;0.05). Furthermore, the composition of the microbiota at 4 weeks was significantly different from that at 2 weeks in the FI group (<italic>P</italic>&lt;0.05). The <italic>Veillonella</italic> abundance was lower at 4 weeks in the FI group (<italic>P</italic>&lt;0.05), but there were no differences in the compositions of the other main microbes between the two groups (<italic>P</italic>&gt;0.05). <italic>Proteobacteria</italic> and <italic>Firmicutes</italic> were dominant in both the FI and FT groups. The concentrations of propanoic, valeric and hexanoic acids were lower in the FI group at 2 weeks, and the levels of isobutyric and valeric acids were lower at 4 weeks after birth (<italic>P</italic>&lt;0.05). The areas under the curves (<italic>AUCs</italic>) of propanoic, butanoic and valeric acids in predicting FI were 0.878, 0.816 and 0.744, respectively. Compared with that in the FT group, the relative bioluminescence of AI-2 was lower in the FI group at 2 weeks (<italic>P</italic>&lt;0.05), and the <italic>AUC</italic> was 0.736.</p></sec><sec><title>Conclusions</title><p>The main composition of the microbiota was not obviously different in infants with FI. Some SCFAs and AI-2 have moderate value in predicting FI.</p></sec>