Association of Fusobacterium nucleatum in human saliva with periodontal status and composition of the salivary microbiome including periodontopathogens

Abstract

Fusobacterium nucleatum promotes dental biofilm formation, increases the prevalence of periodontal disease, and is associated with systemic diseases such as colorectal cancer. However, the relationships of F. nucleatum in saliva with periodontal status and the composition of the salivary microbiome are unclear. Therefore, we analyzed these relationships in saliva samples collected from 611 subjects in Japan. Salivary DNA was extracted and the oral microbiome was analyzed using next-generation sequencing of 16S rRNA. The relationship between F. nucleatum and the community periodontal index was evaluated to examine effects on periodontal status, and α- and β-diversity were analyzed in three groups classified by relative abundance of F. nucleatum. Spearman rank correlation tests were used to examine relationships between the relative abundance of F. nucleatum and oral bacteria. Subjects with high levels of F. nucleatum had a higher prevalence of periodontitis compared with those with lower levels. β-diversity also differed between these two groups. F. nucleatum showed significant correlations with several periodontopathogens, including the red complex, P. intermedia, F. alocis and Fretibacterium ssp.. These results suggest that the relative abundance of F. nucleatum in saliva is associated with periodontal status and the composition of the salivary microbiome, including the red complex and periodontopathogens.