Polymicrobial periodontal infection selectively alters the fecal microbiome in mice: Implications for the oral-gut...

This study aimed to evaluate the impact of polybacterial oral infection with Streptococcus gordonii, Fusobacterium nucleatum, Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia on the gut microbiota in a murine model.

We investigated alterations in fecal bacterial microbiome in infected mice. Fecal samples were collected after the 15th week of infection. Libraries of 16S rRNA amplicons generated from fecal DNA were sequenced using the Illumina sequencing platform.

Feces from infected mice showed upregulation in the classes Verrucomicrobiae, Bacteroidia, Bacilli, and downregulation of Actinomycetia, Coriobacterota, and Clostridia. The genera Lactobacillus (p-value < 0.001) were significantly upregulated, and Acutalibacter (p-value < 0.05), Limosilactobacillus (p-value < 0.05) were downregulated in the infection compared to sham-infected mice. The infection process upregulated 15 strains of bacteria most prominently Akkermansia muciniphila and Dubosiella and downregulated 19 strains. Feces from sham infection had 21 strains of bacteria that completely disappeared in the infected mice, and the feces from infected mice detected 16 strains (Bacteroides, Bifidobacterium globosum) absent in sham-infected mice. Fecal microbiome data indicate that bacterial infection disrupts gut microbiome composition (selective dysbiosis) at class, genus, and strain levels. Periodontal infection appeared to eliminate certain bacterial strains and promoted the emergence of new strains.

Using the Illumina sequencing platform, the present study found that polymicrobial periodontal infection selectively altered the gut microbiome at the class, genus, and strain levels of fecal bacteria. The genomic DNA for S. gordonii, F. nucleatum, and P. gingivalis was detected in the infected mice's feces.