M1 and M2 macrophages phenotypes modulation after stimuli with materials used in endodontic treatment

Abstract The aim of this study was to evaluate the M1 and M2 macrophage modulation after stimuli with different materials used during endodontic treatment. In bone marrow-derived macrophage cell culture, from males C57BL/6 wild-type (WT) mice, gene expression analysis of markers to M1 and M2 macrophages was performed by qRT-PCR (Cxcl10, CxCL9, iNOS, Arg1, Chil3, Retnla and MRC1) and cytokine quantification by Luminex® (GM-CSF, IL-10, IL-6, IL-1β and TNF-α) after exposure to the five endodontic sealers: AH Plus, Sealapex Xpress, Endosequence BC Sealer, BioRoot RCS and a calcium hydroxide-based paste. For normal values, ANOVA test was used, followed by Tukey post-test. For non-normal values, the Kruskall-Wallis test was used. BioRootTM RCS and EndoSequence BC SealerTM stimulated the highest expression of markers for M1 macrophages, while calcium hydroxide-based paste stimulated the lowest expression of these gene markers. For M2 protein markers, BioRootTM RCS presented the highest stimulation while calcium hydroxide-based paste also presented the lowest stimulation. It was concluded that all the evaluated filling materials increased the genetic expression of pro- and anti-inflammatory markers: TNF-α and IL-10 respectively. The others proinflammatory mediators showed differences against the filling materials. However, this process did not induce the inflammatory response polarization, resulting in a hybrid macrophage.

Resumo O objetivo deste estudo foi avaliar a modulação dos macrófagos M1 e M2 após estímulos com diferentes materiais utilizados durante o tratamento endodôntico. Em cultura de células de macrófagos derivados da medula óssea de camundongos machos C57BL/6 wild-type (WT), após a exposição à cinco cimentos endodônticos: AH Plus, Sealapex Xpress, Endosequence BC Sealer, BioRoot RCS e pasta à base de hidróxido de cálcio foi realizada a análise da expressão gênica dos marcadores para macrófagos M1 e M2 por qRT-PCR (Cxcl10, CxCL9, iNOS, Arg1, Chil3, Retnla e MRC1) e quantificação de citocinas por Luminex® (GM -CSF, IL-10, IL-6, IL-1β e TNF-α). Para valores normais, foi utilizado o teste ANOVA, seguido do pós-teste de Tukey. Para valores não normais, foi utilizado o teste de Kruskall-Wallis. BioRootTM RCS e EndoSequence BC SealerTM estimularam maior expressão de marcadores para macrófagos M1, enquanto a pasta à base de hidróxido de cálcio estimulou expressão mais baixa desses marcadores gênicos. Para o marcador de proteínas para M2, BioRootTM RCS apresentou a maior estimulação, enquanto a pasta à base de hidróxido de cálcio também apresentou menor estimulação. Concluiu-se que os materiais obturadores avaliados aumentaram a expressão genética de marcadores pró- e anti-inflamatórios: TNF-α e IL-10 respectivamente. Os demais marcadores pró inflamatórios mostraram diferenças em relação aos materiais obturadores. No entanto, esse processo não induziu a polarização da resposta inflamatória, resultando em um macrófago híbrido.

Radiodensitometric and DXA analyses for the measurement of bone mineral density after systemic alendronate therapy

Precise techniques for the measurement of maxillary bone mineral density (BMD) are useful for the early diagnosis of systemic diseases. The aim of this study was to compare in vivo the efficacy of dual-energy x-ray absorptiometry (DXA) and radiographic densitometry for the measurement of BMD after systemic administration of sodium alendronate. Wistar rats were randomly allocated to a control group (n = 5), which received distilled water, and a sodium alendronate group (n = 8), which received two doses of chemically pure sodium alendronate (1 mg/kg) per week. After 8 weeks, the animals were euthanized, the tibias were removed, and the BMD of the proximal tibial metaphysis was analyzed radiographically and by DXA. The data were subjected to statistical analysis by the Kruskal-Wallis test at a significance level of 5%. Both of the techniques revealed that the alendronate-treated group had a significantly higher BMD (p < 0.05) than the control group after 8 weeks of treatment. Comparing the groups with and without alendronate therapy revealed increases of 14.9% and 29.6% in BMD, as detected radiographically and by DXA, respectively. In conclusion, both of the methods were able to detect an increase in BMD of the proximal tibial metaphysis after alendronate therapy.