Medicação intracanal à base de biocerâmico e hidróxido de cálcio: efeitos sobre a atividade de macrófagos

Abstract

The mechanical-chemical preparation (PMQ) performed during endodontic treatment cannot wholly promote microbial clearance. It is imperative to place an intracanal medication in the treatment consultations. These medications must be biocompatible with the periradicular tissues with which they maintain direct contact. Several intracanal medication compositions have been developed to guarantee desirable antimicrobial properties and tissue biocompatibility. This study aimed to evaluate the effects of the intracanal medications Bio-C Temp (Angelus, Londrina, Paraná, Brazil) and Ultracall XS (Ultradent) on macrophage responses. It was approved by the Ethics Committee on Animal Use (CEUA-UFMG: 2/2020). The experiments were carried out in the Gnotobiology and Immunology laboratory of the Institute of Biological Sciences (ICB) of the Federal University of Minas Gerais. Murine macrophages elicited from C57BL/6, and BALB/c mice were used. Cell viability, cell adhesion, phagocytosis, reactive oxygen species, nitric oxide, TNF-α, and IL-10 productions, and arginase activity were assayed in the presence and absence of drug extracts. Inflammatory macrophages were elicited from the animals' peritoneum after injection of sterile 3% Thioglycolate broth. After aspirating, the macrophages were centrifuged, and the final cell concentration was adjusted according to each proposed assay. Cell viability results showed no interference from Ultracal XS, in both cell lines, at different concentrations of extracts, by the two analysis methods. However, BioC-Temp, at a concentration of 1:4, induced a significant time-dependent reduction in cell viability by the MTT and Flow Cytometry method in both cell lines. The BioC-Temp and Ultracal XS extracts did not interfere in the capacity of cellular adhesion of macrophages BALB/c and C57BL/6, having, however, greater phagocytic capacity by macrophages C57BL/6 than BALB/c, in the presence or absence of the extracts of BioC-Temp and Ultracal XS. Higher production of TNF-α was seen by BALB/c macrophages than C57BL/6 when compared to unstimulated and stimulated cell cultures with Ultracal XS (1:8) and BioC-Temp (1:8). Only cultures treated with UltraCal XS extract (1:8) produced higher levels of IL- 10 in C57BL/6 macrophages when compared to those with BALB/c macrophages. The analyses showed expressive ROS levels in the cells treated with Zymosan A, used as reaction control. There was no difference in the production of ROS under the different treatments in the two cell lines. In turn, C57BL/6 macrophages produced significantly lower levels of ROS when treated with BioC-Temp (1:8 and 1:12). NO production was significantly higher in C57BL/6 macrophages than in BALB/c, which also when treated with Ultracal (1:12) and BioC-Temp (1:8 and 1:12) showed higher arginase activity. Data were analyzed by the Shapiro-Wilk and Levene tests and the Mann-Whitney and Kruskal-Walis or Two-way Anova tests, followed by the Tukey test (P < 0.05). The response of each macrophage subtype, the effect of medications, the different situations presented to macrophages (presence of yeasts and TNF-α) in some experimental situations, and the interaction between these factors was analyzed. Analyzes were performed using SPSS 18.0 Inc software. (Statistical Package for Social Sciences, Chicago, IL, USA). It was concluded that Ultracal XS did not interfere with macrophage responses. In contrast, BioC-Temp, depending on the concentration of the extract used, interfered negatively with cell viability and the production of oxygen radicals (ROS). New studies should be conducted to characterize the components involved in cellular interference promoted by BioC-Temp.