P.gingivalis-induced murine periodontitis activates cardiosplenic axis and shifts spleen extracellular vesicles into pro-senescent endothelial effectors

Abstract Periodontitis, primarily driven by Porphyromonas gingivalis (PG), is an infectious inflammatory disease associated with cardiovascular disease (CVD). Neutrophils represent the first line of defense during periodontitis, and NETosis has emerged as a potential contributor to cardiovascular injury. We previously showed that PG promotes endothelial inflammation and stimulates the release of spleen-derived microvesicles (SMVs). Here, we investigated whether periodontal injury induces distant cardiac alterations and assessed the contribution of SMVs and NETosis to systemic effects. Experimental periodontitis was induced in C57BL/6 mice using silk ligatures, PG-soaked ligatures, or intraperitoneal PG injection. After 2 or 4 weeks, spleen and heart tissues were collected. Heart tissues were assessed for inflammatory markers by PCR. SMV-induced endothelial senescence was assessed in porcine coronary artery endothelial cells using senescence-associated β-galactosidase activity measured by flow cytometry, the eventual impact of NETosis investigated through systemic PAD4 inhibition. PG exposure increased oxidative stress and inflammatory markers in spleen and heart tissues and stimulated SMV release. Isolated SMVs induce endothelial senescence in vitro. PG also altered splenic leukocyte populations, particularly increasing granulocyte and neutrophil proportions. These findings suggest that periodontitis promotes systemic inflammation and spleen-derived microvesicle release, potentially linking oral infection to cardiovascular pathology.