Therapeutic potential of low-dose rosiglitazone in periodontitis: attenuation of inflammation and bone loss through macrophage reprogramming

OBJECTIVES: This study aimed to investigate the effects of different dosages of the peroxisome proliferator-activated receptor gamma (PPAR-γ) agonist rosiglitazone on macrophage polarization, the expression of related inflammatory factors, and alveolar bone loss in the periodontal tissues of rats with experimental periodontitis, thereby providing experimental evidence supporting the potential use of rosiglitazone as a therapeutic agent for periodontitis. MATERIALS AND METHODS: Forty rats were randomly assigned to four groups (n=10 per group): control group (C group), periodontitis group (P group), low-dose rosiglitazone treatment group (L group), and high-dose rosiglitazone treatment group (H group). After two weeks of rosiglitazone treatment via intraperitoneal injection, mandibles were scanned by micro-CT to quantify alveolar bone loss, with measurements of bone volume fraction (BV/TV), cemento-enamel junction to alveolar bone crest (CEJ-ABC) distance, and bone mineral density (BMD). Macrophages examined using immunofluorescence to quantify M1 and M2 proportions, and immunohistochemistry was performed to evaluate expression of IL-1β, IL-10 and osteoclast. RESULTS: Both the L and H groups significantly reduced the M1/M2 macrophage ratio and IL-1β expression in periodontal tissues compared to the P group (p