Inflammatory response of gut, spleen, and liver in mice induced by orally administered Porphyromonas gingivalis

Background Periodontitis is a chronic multifactorial inflammatory disease. Porphyromonas gingivalis is a primary periopathogen in the initiation and development of periodontal disease. Evidence has shown that P. gingivalis is associated with systemic diseases, including IBD and fatty liver disease. Inflammatory response is a key feature of diseases related to this species.Methods C57BL/6 mice were administered either PBS, or P. gingivalis. After 9 weeks, the inflammatory response in gut, spleen, and liver was analyzed.Results The findings revealed significant disturbance of the intestinal microbiota and increased inflammatory factors in the gut of P. gingivalis-administered mice. Administrated P. gingivalis remarkably promoted the secretion of IRF-1 and activated the inflammatory pathway IFN-γ/STAT1 in the spleen. Histologically, mice treated with P. gingivalis exhibited hepatocyte damage and lipid deposition. The inflammatory factors IL-17a, IL-6, and ROR-γt were also upregulated in the liver of mice fed with P. gingivalis. Lee’s index, spleen index, and liver index were also increased.Conclusion These results suggest that administrated P. gingivalis evokes inflammation in gut, spleen, and liver, which might promote the progression of various systemic diseases.