Análise do padrão de resposta imunológica periapical relacionada ao uso dos bisfosfonastos frente à infecção endodôntica induzida em camundongos

Abstract

Antiresorptive drugs are drugs used worldwide to treat bone pathologies such as osteoporosis and other systemic bone diseases. In the present study we examined the effects of Zoledronic Acid (ZOL) on the development of Periapical Lesion (PL) in mice. The objectives of this study were: 1 To analyze the effect of using Zoledronic Acid on periapical lesion formation. 2. To analyze the effect of pulp exposure on cytokines in the periradicular tissues of mice treated with Zoledronic Acid. 3. To compare cytokines in the periradicular tissues of mice treated with Zoledronic Acid with untreated mice. 4. Analyze and compare the reaction of periradicular tissues of mice treated with Zoledronic Acid with untreated mice by means of MicroCT examination. For the experimental analysis, 16 female Balb/C mice (6 weeks) were divided into two experimental groups: Control Group (animals that received serum application) and Acid Group (animals that received Zoledronic acid application), each group consisting of 8 animals . Each group was divided into two subgroups, Group A sacrificed 7 days after the experiment and Group B sacrificed 21 days after the experiment, each subgroup was composed of 4 animals. After dividing the groups, medication induction was performed once a week for 4 weeks intraperitoneally. The Control Group received application of 0.9% NaCl Saline Solution. The Acid Group received application of 125 μg/kg of Zoledronic Acid injectable solution 4 mg/5mL diluted in a sterile solution at 0.9%. After drug induction, pulp exposure of the maxillary left and right first molars was performed. The pulp chambers were opened until the canal entrances. The animals were sacrificed after 7 and 21 days of pulp exposure. The periapical tissues that surround the root apices were removed aseptically and the molars on the left side for further analysis in MicroCT and the right side for PCR. The samples were submitted to statistical tests. In both periods of 7 and 21 days, the Control Group had a greater area and volume of periapical lesions compared to the other Acid Groups. Periapical lesion size increased in all experimental groups when comparing 7 to 21 days. The TNF-α cytokine expression was significantly higher in the Control Group at 7 and 21 days when compared to the Acid Group. A greater expression of IL-6 cytokines was observed in the period of 7 days by the Control Group. IL-1β had an increase in its expression in the period of 21 days in the Control Group. In conclusion, the Acid Group presented a lower induction of periapical lesions. Furthermore, the results found suggest that the use of Zoledronic acid seems to somehow inhibit IL-1β-induced bone resorption.