AUTHOR=Li Yinan , Liu Min , Kong Bingtan , Zhang Ganlin , Zhang Qing 

TITLE=The role of selenium intervention in gut microbiota homeostasis and gene function in mice with breast cancer on a high-fat diet

JOURNAL=Frontiers in Microbiology

VOLUME=15

YEAR=2024

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2024.1439652

DOI=10.3389/fmicb.2024.1439652

ISSN=1664-302X

ABSTRACT=<sec id="sec1"><title>Objective</title><p>This study aimed to investigate the effect of selenium on gut microbiota in mice with breast cancer under a high-fat diet.</p></sec><sec id="sec2"><title>Methods</title><p>A total of 12 female BALB/c mice were randomly divided into two groups: 4 T1 + selenium+ high-fat diet group and 4 T1 + high-fat diet group. Mice were injected with 4 T1 cells on the right 4th mammary fat pad and kept on a high-fat diet. Fecal samples were collected, and DNA was extracted for metagenomic sequencing and bioinformatics analysis. Relevant target genes and pathways were annotated and metabolically analyzed to explore the intervention effect of selenium on breast cancer in the high-fat diet state.</p></sec><sec id="sec3"><title>Results</title><p>Selenium supplementation in the high-fat diet altered the composition and diversity of gut microbiota in mice with breast cancer. The gut microbial composition was significantly different in the selenium intervention group, with an increased abundance of Proteobacteria, Actinobacteria, and Verrucomicrobia phyla and species such as <italic>Helicobacter ganmani</italic>, <italic>Helicobacter japonicus</italic>, and <italic>Akkermansia muciniphila</italic>, while phyla, such as Bacteroidetes, Firmicutes, Deferribacteres, and Spirochaetes, and species, such as <italic>Prevotella</italic> sp. <italic>MGM2</italic>, <italic>Muribaculum intestinale</italic>, <italic>Lactobacillus murinus</italic>, and <italic>Prevotella</italic> sp. <italic>MGM1,</italic> were decreased. Functional analysis revealed differential expression of genes related to carbohydrate-active enzymes, pathogen–host interactions, cell communication, cell auto-induction, membrane transporters, and virulence factors. Furthermore, 37 COGs and 48 metabolites with rising metabolic potential in the selenium intervention group were predicted.</p></sec><sec id="sec4"><title>Conclusion</title><p>Selenium alters the homeostasis of gut microbiota in mice with breast cancer on a high-fat diet, affecting their composition, abundance, and associated metabolism. These findings suggest that the mechanism involves interfering with gut microbiota homeostasis, leading to altered synthesis of tumor-associated proteins and fatty acids and inducing tumor cell apoptosis and pyroptosis.</p></sec>