Efeito de cimentos obturadores endodônticos sobre a atividade de macrófagos M1 e M2

Abstract

Root canal sealers are brought into contact with periapical tissues when finishing endodontic therapy, even when they are not severely extruded through root canal orifices. Therefore, their biological properties are considered to be important. Macrophages have a central role in both innate immunity and adoptive responses. Recent studies have revealed that there are two types of macrophages: M1 (activated by IL-12) and M2 (activated in the absence of IL-12) based on their ability to produce different responses. This study aimed at analyzing the effect of two endodontic sealers (PCS EWT® and Endofill®) on the activity ofM1 (obtained from C57BL/6 mice) and M2 (obtained from IL-12/23 p40 deficient C57BL/6 mice) inflammatory macrophages. Cellular viability, cellular adherence, phagocytosis of S. boulardii, production of reactive oxygen intermediates (ROIs), nitric oxide (NO), TNF, IL-12 and IL-10 were assessed. Production of ROIs was stimulated by zymosan. Production ofcytokines was stimulated with Fusobacterium nucleatum, eptostreptococcus anaerobius and IFN-g. Cellular viability was not affected in the presence of either endodontic sealers however, the adherence and the phagocytic activity were impaired. Both sealers inhibited ROIs production only by M1 macrophages. On the other hand, NO production by M1 macrophages was not affected by the sealers, while the same sealers impaired NO production by M2 macrophages when stimulated with F. nucleatum. None of the sealers affected IL-12p70 production by M1 macrophages. TNF-a production by M1 macrophages, when stimulated with F. nucleatum, was impaired in the presence of PCS EWT®. However, the pre-incubation with PCS EWT® or Endofill® affected the production of this cytokine by M1 macrophages when the cultures were stimulated with P. anaerobius in the presence of IFN-g. TNF-a production by M2 macrophages, when stimulated with F. nucleatum and IFN-g, was impaired by both endodontic sealers. On the other hand, the production of this cytokine by M2 macrophages was inhibited only by Endofill® when the cultures were stimulated with P. anaerobius and IFN-g. IL-10 production by M1 macrophages was not affected by either root canal sealer. PCS EWT® inhibited IL-10 production by M2 macrophages only when the cultures were stimulated with P. anaerobius. We can conclude that both endodontic sealers may impair macrophage activities.