The influence of bioceramic cements on the activity of macrophages of different lineages: a laboratory study.

INTRODUCTION: The repair process of periradicular tissues depends, among other factors, on the properties of endodontic cements. One of the main cells involved in this process are macrophages. MATERIALS AND METHODS: Murine peritoneal macrophages obtained from C57BL/6 (MBL6) and BALB/c (MBalb) mice, respectively, were cultured with capillaries containing or not Endosequence BC Sealer® (BC), Sealer Plus BC® (MK), Bio C Sealer (Ang) and MTA®. Cell viability was measured by trypan blue and MTT methods at 24, 48 and 72 hours. Cell adhesion, phagocytosis of S. boulardii, production of reactive oxygen species (ROS), nitric oxide (NO), and the cytokines TNF-α and TGF-ß, were also evaluated. The data were analysed using the ANOVA test (p<0.05). RESULTS: Cell viability was similar between bioceramic sealers and MTA (p>0.05). There was no statistical difference between both macrophages when adherence and phagocytose were assayed. The presence of inflammation stimulus significantly altered the production of ROS by MBL6 macrophages in contact with the cements. The production of TGF-ß was similar for both lineages of macrophages. CONCLUSIONS: This study shows that the evaluated bioceramic cements do not interfere with MBL6 and MBalb macrophages adhesion, phagocytic capacity, as well as TGF-ß production. The cements stimulated the production of ROS by MBL6 macrophages in response to induced inflammation, potentially favouring the elimination of residual pathogens.

High-plasticity mineral trioxide aggregate and its effects on M1 and M2 macrophage viability and adherence, phagocyte activity, production of reactive oxygen species, and cytokines.

Objectives: This study evaluated the effects of high-plasticity mineral trioxide aggregate (MTA-HP) on the activity of M1 and M2 macrophages, compared to white MTA (Angelus). Materials and Methods: Peritoneal inflammatory M1 (from C57BL/6 mice) and M2 (from BALB/c mice) macrophages were cultured in the presence of the tested materials. Cell viability (MTT and trypan blue assays), adhesion, phagocytosis, reactive oxygen species (ROS) production, and tumor necrosis factor (TNF)-α and transforming growth factor (TGF)-ß production were evaluated. Parametric analysis of variance and the non-parametric Kruskal-Wallis test were used. Results were considered significant when p < 0.05. Results: The MTT assay revealed a significant decrease in M1 metabolism with MTA-HP at 24 hours, and with MTA and MTA-HP later. The trypan blue assay showed significantly fewer live M1 at 48 hours and live M2 at 48 and 72 hours with MTA-HP, compared to MTA. M1 and M2 adherence and phagocytosis showed no significant differences compared to control for both materials. Zymosan A stimulated ROS production by macrophages. In the absence of interferon-γ, TNF-α production by M1 did not significantly differ between groups. For M2, both materials showed higher TNF-α production in the presence of the stimulus, but without significant between-group differences. Likewise, TGF-ß production by M1 and M2 macrophages was not significantly different between the groups. Conclusions: M1 and M2 macrophages presented different viability in response to MTA and MTA-HP at different time points. Introducing a plasticizer into the MTA vehicle did not interfere with the activity of M1 and M2 macrophages.

Avaliação da resposta de macrófagos inflamatórios frente aos cimentos biocerâmico / Evaluation of the inflammatory macrophagus response in front of bioceramic cements

As propriedades e a composição dos cimentos endodônticos podem influenciar nas reações inflamatórias perirradiculares e comprometer o sucesso do tratamento endodôntico. Os macrófagos estão presentes no infiltrado inflamatório periapical, envolvidos na eliminação e controle microbiano nesta região. Este estudo avaliou a atividade de viabilidade celular, aderência, fagocitose da levedura S. boulardii, produção de espécies reativas de oxigênio (ROS), óxido nítrico (NO), e das citocinas (TNF- α e TGF-ß) por macrófagos peritoneais murinos de perfil pró-inflamatório (M1) e anti-inflamatório (M2) obtidos de camundongos C57BL/6 e BALB/c, respectivamente. Os macrófagos foram obtidos e a suspensão celular foi colocada em contato com capilares contendo ou não os cimentos Endosequence BC Sealer (BC), Sealer PLus BC (MK), Bio-c Sealer (Ang) e MTA. Mensurou-se a viabilidade celular pelos métodos da exclusão do azul de tripan e por MTT nos tempos 24, 48 e 72 horas. No primeiro ensaio, foi encontrada viabilidade celular semelhante entre os biocerâmicos e o MTA nos tempos testados; no entanto, houve diferença significativa em 72h entre BC e controle (capilar vazio); para o MTT houve diferença com o controle entre: Ang (24h), BC e MK (48h) para M1; para M2, MK (24h), Ang (48h) e BC, Ang, MTA (72h) (p<0,05). Nos ensaios de aderência e de fagocitose não houve diferença significativa para os materiais testados em ambos os subtipos de macrófago. Em relação à produção de ROS, houve uma maior expressão para M1 em comparação com M2. Na ausência do Zimosan não houve produção significativa entre os cimentos, para ambos os macrófagos. Na presença do Zimosan A, o cimento MK apresentou maior produção que os grupos tratados com Ang e MTA, e controle (p<0,05) para macrófago M1. No ensaio de detecção de NO, na presença do estímulo, todos os cimentos testados apresentaram diferenças significativas com o controle, para o macrófago M1. Na dosagem de TNF houve diferença significativa somente para macrófagos M1, com uma maior produção pelo cimento Endosequence BC, mesmo sem estímulo; sobretudo, quando estimulados com IFN-γ, BC apresentou maior produção que os grupos tratados MK e Ang; e, todos os grupos apresentaram diferenças em relação ao controle. A dosagem de TGF- ß não apresentou diferenças para os grupos tratados na presença ou ausência do estímulo. Concluiu-se que a composição dos biocerâmicos, à base de silicato de cálcio, semelhante à do MTA, permitiu que os biocerâmicos não interferissem nas respostas de macrófagos de ambas as linhagens testadas.

The properties and compositions of endodontic sealers may influence the periradicular inflammatory reactions and compromise the success of endodontic treatment. Macrophages are present in the periapical inflammatory infiltrate, being involved in the microbial clearance in this region. This study evaluated the cell viability, adhesion, phagocytosis of S. boulardii, production of reactive oxigen species (ROS) and nitrite oxide (NO) and cytokines (TNF and TGF-ß) by murine peritoneal macrophages of pro-inflammatory (M1) and anti-inflammatory (M2) profiles obtained from C57BL / 6 and BALB / c mice, respectively. Macrophages were obtained and the cell suspension was placed in contact with capillaries containing or not the sealers Endosequence BC Sealer (BC), Sealer PLus BC (MK), Bio-c Sealer (Ang) e MTA. Cell viability was measured by the methods of tripan blue exclusion and by MTT at times 24, 48 and 72 hours. In the first assay, similar cell viability was found between the bioceramic and the MTA in the tested times; However, there was a significant difference in 72h between BC and control (empty capillary); For the MTT there was a difference with the control between: Ang (24h), BC e MK (48h) para M1; para M2, MK (24h), Ang (48h) e BC, Ang, MTA (72h) (p<0,05). n the adherence and phagocytosis assays there was no significant difference for the materials tested in both macrophage subtypes. Regarding the production of ROS, there was a greater expression for M1 compared to M2. In the absence of Zymosan there was no significant production between the sealers for both macrophages. In the presence of Zimosan A, the MK cement presented higher production than the groups treated with Ang and MTA, and control (p <0.05) for M1 macrophages. n the NO detection assay, in the presence of the stimulus, all the sealers tested showed significant differences with the control, for the M1 macrophage. In the TNF there was only difference for M1, with a higher production by the Endosequence BC even without stimulus, when stimulated with IFN-γ, BC showed higher production than the treated groups MK and Ang; and all groups showed differences in relation to control. The TGF-ß dosage did not present difference for the groups treated in the presence or absence of the stimulus. It was concluded that the calcium silicate composition, similar to that of MTA, allowed the bioceramics to not interfere in the macrophages responses of both tested strains.