Abstract
OBJECTIVE: To evaluate the effects of gastric administration of the highly leukotoxic Aggregatibacter actinomycetemcomitans JP2 strain (Aa JP2), with or without ligature-induced periodontitis, on periodontal and small intestinal tissues in a rat model. METHODOLOGY: Forty-eight-week-old male Wistar rats were divided into four groups (n=10/group): Control (CG), Periodontitis (PG), Periodontitis and Aa JP2 (PAaG), and Aa JP2 only (AaG). Ligatures were placed in PG and PAaG on day one and maintained for 42 days. After six weeks of twice-weekly gastric Aa JP2 inoculation, mandibles and small intestines were analyzed using stereomicroscopy, micro-computed tomography (CT), and histopathology to assess alveolar bone loss, trabecular architecture, inflammatory infiltrate, vascular congestion, goblet cell density, and villus morphology. Statistical analyses included the Kruskal-Wallis, Mann-Whitney, and Chi-square tests for group comparisons (p<0.05), as well as Spearman's correlation test. RESULTS: PG and PAaG exhibited significantly greater bone loss compared to CG and AaG (p<0.05). Micro-CT analysis revealed reduced trabecular thickness in AaG (342.4±23.1µm) compared to PG (378.2±28.1µm) and PAaG (385.5±45.1µm) (p<0.05). PAaG and AaG presented higher inflammatory infiltrate scores (>751 inflammatory cells) compared to CG and/or PG (p<0.05). Elevated vascular congestion and/or goblet cell hyperplasia in the jejunum and ileum were observed in PAaG and AaG compared to CG and PG (p<0.05). Villus height (duodenum/ileum) and villus width (jejunum/ileum) differed significantly among groups (p<0.0001). Significant correlations were identified: the alveolar bone volume/total volume ratio was positively associated with duodenal vascular congestion (rho=0.738; p=0.037); the periodontal inflammatory infiltrate was positively associated with jejunal goblet cell counts (rho=0.704; p=0.007); alveolar bone loss was positively associated with both duodenal and jejunal villus height (rho≥0.762; p<0.05); and bone volume was negatively associated with both jejunal vascular congestion (rho=-0.696; p=0.003) and jejunal goblet cell counts (rho=-0.617; p=0.011). CONCLUSIONS: Gastric inoculation with Aa JP2 exacerbates ligature-induced periodontitis and independently induces intestinal morphological changes.