Special Effects of Endodontic Inflammation on the Rat Aorta

Objective: The objective of this study was to compare the expression of biomarkers of atherosclerosis within serum and the ascending aorta between female and male rats, following creation of experimental periapical abscesses. Methods: Sprague-Dawley rats were divided into four groups: females with induced pulpal inflammation (FExp, n=16), sham-operated control females (FC, n=16), males with induced pulpal inflammation (MExp, n=16), and sham operated control males (MC, n=16). To induce periapical inflammation, the pulps of the first and second maxillary right molars were exposed to the oral cavity. 28 days later, serum and the ascending aorta were collected. Serum CRP, 17b- estradiol, testosterone, IL-6, TNF-a, and IL-1b concentrations were measured by ELISA. Aortas were embedded in paraffin, sectioned, and stained with H & E and antibodies to IL-6, IL-1b, IKK b, and bcatenin. Biomarker (+) cells were counted within the endothelium and adjacent foam cells using Sigma Scan Pro software. Data were compared by factorial ANOVA and post-hoc Tukey tests. Groups were considered to be significantly different when p<0.05. Results: Both MExp and FExp rats had significantly higher concentrations of serum CRP, IL-6, TNF-a, and IL-1b when compared to either MC or FC, and those concentrations were significantly greater in MExp than in FExp (p<0.05). IL-6, IL-1b, IKKb, and bcatenin (+) cells were significantly greater in MExp and FExp than in MC or FC, and in MExp than in FExp rats (p<0.05). Conclusion: Estrogen likely modulates the risk factor for atherosclerosis in females, but probably not in males.