Mediterranean diet component oleic acid decreases systemic impact of periodontal Porphyromonas gingivalis-infection in age: addressing role of stress resistance and microbiome

Periodontitis (PD) is an age-associated infectious periodontal disease driven by dysbiosis and hyperinflammatory host response, resulting in bone and tissue loss. Often linked to systemic inflammatory comorbidities, modulating host response emerged as promising clinical target. This study investigates whether nutritional intervention mitigates age-associated systemic impact of oral infection with PD key pathogen Porphyromonas gingivalis. Young (5 weeks) and aged (≥73 weeks) mice received palmitic acid-enriched Western-diet (PA-ED) or Mediterranean-diet enriched with oleic acid (OA-ED), both known for immunomodulatory properties. PA-ED exacerbated oral bone loss and systemic effects, particularly in aged mice, correlated with gut microbiota destabilization and impaired stress responses. Further, PA-ED enhanced osteoclast differentiation and primed bone marrow cells towards inflammation. Contrarily, OA-ED mitigated these effects. Osteoblasts showed baseline inflammation and reduced responsiveness in aged mice, thereby promoting a pro-inflammatory micro-environment. Findings suggest OA-ED as protective, especially for the elderly, by limiting local and systemic tissue damage associated with PD.