Effect of corn syrup consumption on bone and inflammatory parameters in rats with spontaneous periodontitis

Background: Although added sugar consumption is associated with altered periodontal parameters in humans and alveolar bone loss in rodents, the immunoinflammatory pathways involved and the links between local periodontal and systemic effects are not yet defined. The purpose of this study was to evaluate the effect of chronic corn syrup (CS) consumption on alveolar bone loss, bone microstructure, and local/systemic inflammatory parameters in rats. Methods: Male Wistar rats (n = 8 per group) were divided into two groups: Control — standard diet and water ad libitum; CS — standard diet and 20% corn syrup for 12 h per day for 12 weeks. Alveolar bone loss was assessed by radiography, and bone microstructure of right hemimandibles and left femurs by micro-computed tomography (micro-CT). Interleukin (IL)-1β, IL-6, IL-17, and tumor necrosis factor (TNF)-α cytokines were measured in gingival tissue and plasma. Periodontal, liver, and kidney inflammation were evaluated histologically. Results: The CS group consumed less food and more liquid (p < 0.05) and showed greater alveolar bone loss along with reduced alveolar trabecular number (p < 0.05), with no changes in femoral microstructure (p > 0.05). Gingival TNF-α and IL-17 levels were higher in the CS group (p < 0.05). Histologically, the CS group showed increased periodontal inflammatory infiltrate and more osteoclasts in the periodontal ligament. No differences were found between groups in plasma cytokines and liver or kidney histology. Conclusion: High CS consumption aggravated spontaneous periodontitis in rats, resulting in alveolar bone loss and increased gingival inflammatory cytokines, with no changes in the systemic parameters evaluated over the study period.