Porphyromonas gingivalis Infection Promotes the Expression of Inflammatory Biomarkers in Atherosclerosis and Periodontitis: An Experimental Study Using an Apolipoprotein E-Deficient Mouse Model

Objectives P. gingivalis, a major periodontal pathogen, accelerates the development of atherosclerosis. We aimed to validate an animal model of atherosclerosis and periodontitis and investigate the inflammatory effects of P. gingivalis infection on these diseases. Methods We treated 8-week-old apolipoprotein E-deficient (ApoE-/-) mice with PBS supplemented with 2% CMC and P. gingivalis every two days for a total of 20 times. Aorta, blood and maxillary bone samples were collected and used for Oil Red O staining, micro-CT, enzyme-linked immunosorbent assays (ELISAs) and real-time PCR. Results Micro-CT analysis revealed remarkable resorption of alveolar bone in the maxillary region after P. gingivalis infection. Frozen aortic root sections stained with Oil red O revealed lipid deposition and plaque formation. The levels of inflammatory biomarkers such as TNF-a, IFN-γ, IL-6, VEGF and RANTES increased, whereas that of b-FGF decreased. Additionally, the mRNA levels of ACTA2, HO-1, STAT3 and T-bet in the aorta were significantly different between the P. gingivalis infection group and the control group. Conclusion An animal model of atherosclerosis and periodontitis caused by P. gingivalis infection was successfully established, and changes in the levels of inflammatory markers were observed, suggesting that periodontitis may serve as an intervenable risk factor for atherosclerosis. By measuring inflammatory biomarker levels, potential indicators for early clinical risk assessment and prognostic monitoring were identified.