The Link Between Periodontal Diseases and Ulcerative Colitis Through Subgingival and Gut Mucosal Microbiome

Aim(s): To characterize the subgingival and colonic mucosal microbiome compositions in patients with ulcerative colitis (UC) diagnosed with periodontal health and diseases, compared to patients without inflammatory bowel disease (non-IBD) controls, and to explore the microbial signatures in the subgingival and intestinal microbiome that link periodontal diseases and UC.Materials and Methods: A total of 52 patients (25 with active UC and 27 non-IBD) were enrolled. Based on their periodontal health status, patients were categorized into subgroups of healthy periodontium, gingivitis, and periodontitis. Subgingival plaque samples and multiple colonic mucosa biopsies were collected from each patient on the same day before any UC-related therapy. The microbial compositions of the samples were analyzed using 16S ribosomal RNA (rRNA) gene high-throughput sequencing.Results: Beta diversity (Bray-Curtis dissimilarity) in plaque samples varied significantly with periodontal health status in the UC group (p=0.013), but not in the non-IBD group (p=0.236). The Neisseria genus was consistently higher in plaque samples from UC patients across all periodontal health statuses. In biopsy samples, significant diversity differences (alpha- and beta-diversity) were observed only in the non-IBD group (p<0.05). No significantly different taxa were found between UC and non-IBD mucosal biopsy samples in patients with gingivitis and periodontitis. Streptococcus and Prevotella were the most abundant and shared genera between plaque and biopsy samples in the UC group.Conclusion: The significant enrichment of Neisseria in subgingival plaque could serve as an oral biomarker for UC diagnosis, independent of periodontal health status. Microbial diversity in colonic mucosa biopsies did not show significant differences in periodontal health and disease for UC patients.