Culture of mouse peritoneal macrophages with mouse serum induces lipid bodies that associate with the parasitophorous vacuole and decrease their microbicidal capacity against Toxoplasma gondii

Lipid bodies [lipid droplets (LBs)] are lipid-rich organelles involved in lipid metabolism, signalling and inflammation. Recent findings suggest a role for LBs in host response to infection; however, the potential functions of this organelle in Toxoplasma gondii infection and how it alters macrophage microbicidal capacity during infection are not well understood. Here, we investigated the role of host LBs in T. gondii infection in mouse peritoneal macrophages in vitro. Macrophages cultured with mouse serum (MS) had higher numbers of LBs than those cultured in foetal bovine serum and can function as a model to study the role of LBs during intracellular pathogen infection. LBs were found in association with the parasitophorous vacuole, suggesting that T. gondii may benefit from this lipid source. Moreover, increased numbers of macrophage LBs correlated with high prostaglandin E2 (PGE2) production and decreased nitric oxide (NO) synthesis. Accordingly, LB-enriched macrophages cultured with MS were less efficient at controlling T. gondii growth. Treatment of macrophages cultured with MS with indomethacin, an inhibitor of PGE2 production, increased the microbicidal capacity against T. gondii. Collectively, these results suggest that culture with MS caused a decrease in microbicidal activity of macrophages against T. gondii by increasing PGE2 while lowering NO production.

Atividade anti-inflamatória do óleo-resina da Copaífera reticulata em modelo inflamatório de edema de pata / Anti-inflammatory activity of the oil-resin Copaífera reticulata of model inflamatory paw edema

Objetivo: avaliar a ação do óleo-resina de copaíba da espécie copaifera reticulata como anti-inflamatório em modelos experimentais de reação inflamatória aguda. Método: o estudo experimental foi realizado no Laboratório de Imunofarmacologia da Fundação Instituto Oswaldo Cruz ? FIOCRUZ/RJ, foram utilizados 30 (trinta) camundongos da linhagem Swiss Webster (SW). O óleo-resina de copaíba utilizada foi extraído de árvore da espécie Copaífera reticulata. O modelo de inflamação aguda induzida por carragenina foi utilizado para avaliar o efeito anti-inflamatório das concentrações, foi utilizado o teste estatístico de Kruskal-Wallis para comparar os valores medianos conforme os grupos com nível de significância alfa = 0,05. Resultados: no grupo C500 ocorreu significativa redução do volume no instante T3; somente os grupos Indo e C10 apresentaram significativa redução do volume em T6. Não houve diferença estatisticamente significante no Índice de Inibição do Edema nos grupos (Indo, C10, C100 e C500) nos intantes T1, T3 e T6. Conclusão: a atividade anti-inflamatória do óleo-resina foi confirmada pelo modelo do edema de pata induzido por carragenina através da redução do volume deslocado.

Objective: To evaluate the action of the oil-resin of Copaiba Copaifera reticulata as anti-inflammatory effect in experimental models of acute inflammatory reaction. Method: A total of 30 (thirty) mice of Swiss strain Webster (SW). The oil-resin of Copaiba used was extracted from tree species Copaifera reticulata. The model of acute inflammation induced by carrageenan was used to evaluate the anti-inflammatory effect of the extracts, we used the statistical test of Kruskal-Wallis test to compare the median values for the different groups with a significance level alpha = 0.05. Results: The group C500 was a significant reduction in the volume at time T3, only the Indus and C10 groups showed significant reduction in volume at T6. There was no statistically significant difference in the Index of Inhibition of edema in groups (Indo, C10, C100 and C500), in the instant, T1, T3 and T6. Conclusion: The anti-inflammatory activity of oil-resin was confirmed by the model of paw edema induced by carrageenan by reducing the volume displaced.