Stachyose inhibits vancomycin-resistant Enterococcus colonization and affects gut microbiota in mice

Authors: ZHU, SIYI - Chinese Academy Of Medical Sciences; LI, XIANPING - Chinese Academy Of Medical Sciences; SONG, LIQIONG - Chinese Academy Of Medical Sciences; HUANG, YUANMING - Chinese Academy Of Medical Sciences; XIAO, YUCHUN - Chinese Academy Of Medical Sciences; CHU, QIONGFANG - Chinese Academy Of Medical Sciences; KANG, YING - Chinese Academy Of Medical Sciences; DUAN, SUFANG - China National Research Institute Of Food & Fermentation Industries Corporation Limited; WU, DAYONG - Jean Mayer Human Nutrition Research Center On Aging At Tufts University; REN, ZHIHONG - Chinese Academy Of Medical Sciences

Submitted to: Microbial Pathogenesis
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/8/2021
Publication Date: 7/17/2021
Citation: Zhu, S., Li, X., Song, L., Huang, Y., Xiao, Y., Chu, Q., Kang, Y., Duan, S., Wu, D., Ren, Z. 2021. Stachyose inhibits vancomycin-resistant Enterococcus colonization and affects gut microbiota in mice. Microbial Pathogenesis. 59:105094. https://doi.org/10.1016/j.micpath.2021.105094.
DOI: https://doi.org/10.1016/j.micpath.2021.105094

Interpretive Summary: Vancomycin-resistant Enterococcus (VRE)-caused infections involving multiple organs are rising globally. Currently antibiotics are the main measure of treating VRE. However antibiotic resistance has prompted researchers to seek alternative strategies such as altering gut microbiota through use of natural dietary components. Supported by the Chinese Academy of Medical Sciences and the U.S. Department of Agriculture, researchers evaluated whether stachyose (a sugar compound present in numerous vegetables) inhibits VRE infection as well as the involvement of gut microbiota for its effect in a mouse model. Results showed that stachyose supplementation inhibited VRE colonization, which was correlated with altered composition of the gut microbiota. These results suggest that consuming vegetables rich in stachyose may help control drug-resistant VRE infection.

Technical Abstract: Vancomycin-resistant Enterococcus (VRE) caused nosocomial infections are rising globally. Multiple measures have been investigated to address this issue, altering gut microbiota through dietary intervention represents one of such effort. Stachyose can promote probiotic growth, which makes it a good candidate for potentially inhibiting VRE infection. This study aimed to determine whether stachyose inhibits VRE colonization and investigated the involvement of gut microbiota on this effect of stachyose. In the VRE-infection experiment, 6-week old female C57/6 J mice pre-treated with vancomycin were infected with 2 × 108 CFU VRE via gavage. These mice then received oral administration of stachyose or PBS as control for 7 days. Two groups of uninfected mice also received daily gavage of stachyose or PBS for 7 days to observe the impact of stachyose treatment on normal mice. Fresh fecal and colon samples were collected, then VRE colonization, gut microbiota and gene expression were respectively assessed using cultivation, 16s rRNA sequencing and RNA-sequencing in two parallel experiments, respectively. In VRE-infected mice, stachyose treatment significantly reduced VRE colonization on days 9 and 10 post-infection. Stachyose treatment increased the relative abundance of Porphyromonadaceae, Parabacteroides, and Parabacteroides distasonis compared to the PBS-treated infection mice (P < 0.01). Uninfected mice treated with stachyose showed a significant increase in Lactobacillaceae and Lactobacillus compared to the PBS-treated uninfected mice (P < 0.05). RNA-sequencing results showed that stachyose treatment in VRE-infected mice increased expression of genes involved in TNF and IL-17 signaling pathways. Stachyose treatment also up-regulated Hsd17b14, Cyp3a44, Arg1, and down-regulated Pnliprp2, Ces1c, Pla2g4c genes involved in metabolic pathway of uninfected mice. In conclusion, stachyose supplementation can effectively inhibit VRE colonization and probably in altering composition of the microbiome, which can in turn result in changes in expression of genes. Stachyose may also benefit health by increasing the abundance of Lactobacillus and expression of genes involving in metabolic pathway in normal mice.