BACKGROUND The knowledge about eicosanoid metabolism and lipid droplet (LD) formation in the Leishmania is very limited and new approaches are needed to identify which bioactive molecules are produced of them. OBJECTIVES Herein, we compared LDs and eicosanoids biogenesis in distinct Leishmania species which are etiologic agents of different clinical forms of leishmaniasis. METHODS For this, promastigotes of Leishmania amazonensis, L. braziliensis and L. infantum were stimulated with polyunsaturated fatty acids (PUFA) and LD and eicosanoid production was evaluated. We also compared mutations in structural models of human-like cyclooxygenase-2 (GP63) and prostaglandin F synthase (PGFS) proteins, as well as the levels of these enzymes in parasite cell extracts. FINDINGS PUFAs modulate the LD formation in L. braziliensis and L. infantum. Leishmania spp with equivalent tissue tropism had same protein mutations in GP63 and PGFS. No differences in GP63 production were observed among Leishmania spp, however PGFS production increased during the parasite differentiation. Stimulation with arachidonic acid resulted in elevated production of hydroxyeicosatetraenoic acids compared to prostaglandins. MAIN CONCLUSIONS Our data suggest LD formation and eicosanoid production are distinctly modulated by PUFAS dependent of Leishmania species. In addition, eicosanoid-enzyme mutations are more similar between Leishmania species with same host tropism.

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.

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.