The oral microbiome profile and biomarker in Chinese type 2 diabetes mellitus patients

Oral microbiota maintains a dynamic ecological balance with the host. However, a disruption in this balance can lead to oral diseases such as dental caries and periodontitis. Several studies suggest differences in microbial composition in the oral cavity between patients with T2DM and nondiabetic patients. However, there is inadequate oral microbiome-related data from Chinese patients with T2DM, and the difference in microbiome profile between Chinese patients with T2DM and other ethnicities needs to be investigated further.

Oral swab samples were collected from 280 adult patients with T2DM and 162 healthy controls. Illumina sequencing was performed on oral samples targeting V1-V2 region of 16S rRNA gene and sequence analysis was carried in the QIIME.

Patients with T2DM and healthy cohorts exhibited distinct oral microbial clusters based on principal coordinate analysis (PCoA). The Firmicutes/Bacteroidetes ratio increased in T2DM and T2DM patients presented significantly higher numbers of Neisseria, Streptococcus, Haemophilus, and Pseudomonas genera, and lower numbers of Acinetobacteria compared with healthy controls. When compared with the available published data of oral and gut microbiome associated with T2DM patients, we found the ratio of Firmicutes/Bacteroidetes and the abundance of Haemophilus could be a specific microbial biomarker in Chinese patients with T2DM.

Our study revealed a significant difference in the oral microbiota between T2DM patients and healthy individuals. We identified 25 taxa, including 6 genera, with significant difference in abundance between T2DM and healthy controls.