RESUMEN
The influence of black carbon nanoparticles on J774.A1 murine cells was investigated with the objective of exploring the cytotoxicity of black carbon functionalized with ethylenediamine CB-EDA. The results showed that CB-EDA has a cytotoxic profile for J774.A1 macrophages in a time- and dose-dependent manner. When phagocytosed by the macrophage, CB-EDA triggers a mechanism that leads to apoptosis. In this process, there is an increase in oxidative stress pathways due to the activation of nitric oxide and then ROS. This causes an imbalance in redox function and a disruption of membrane integrity that occurs due to high levels of LDH, in addition to favoring the release of the pro-inflammatory cytokines IL-6, IL-12, and tumor necrosis factor (TNF) in an attempt to modulate the cell. However, these stimuli are not sufficient to repair the cell and the level of mitochondrial integrity is affected, causing a decrease in cell viability. This mechanism may be correlated with the activation of the caspasse-3 pathway, which, when compromised, cleaves and induces cells death via apoptosis, either through early or late apoptosis. In view of this, the potential for cell damage was investigated by analyzing the oxidative and inflammatory profile in the macrophage lineage J774.A1 and identifying potential mechanisms and metabolic pathways connected to these processes when cells were exposed to NP CB-EDA for both 24 h and 48 h.
RESUMEN
Schistosomiasis, caused by Schistosoma mansoni trematode worm, affects more than 1.5 million people in Brazil. The current treatment consists in the administration of Praziquantel, the only medicine used for treatment for more than 40 years. Some of the limitations of this drug consist in its inactivity against schistosomula and parasite eggs, the appearance of resistant strains and non-prevention against reinfection. Thus, the objective of this study was to evaluate the effect of immunization with recombinant functional enzymes of the purine salvage pathway of S. mansoni, Nucleoside Diphosphate Kinase (NDPK) and Adenylosuccinate Lyase (ADSL), to evaluate the host immune response, as well as the parasite load after vaccination. For this, Balb/c mice were divided into 5 groups: control (uninfected and untreated), non-immunized/infected, NDPK infected, ADSL infected, and NDPK + ADSL infected. Immunized groups received three enzyme dosages, with a 15-day interval between each dose, and after 15 days of the last application the animals were infected with 80 cercariae of S. mansoni. On the 47th day after the infection, fecal eggs were counted and, on the 48th day after the infection, the evaluation of leukocyte response, parasite load, antibody production, cytokines quantification, and histopathological analysis were performed. The results showed that immunizations with NDPK, ADSL or NDPK + ADSL promoted a discreet reduction in eosinophil counts in lavage of peritoneal cavity. All immunized animals showed increased production and secretion of IgG1, IgG2a, and IgE antibodies. Increased production of IL-4 was observed in the group immunized with the combination of both enzymes (NDPK + ADSL). In addition, in all immunized groups there were reductions in egg counts in the liver and intestine, such as reductions in liver granulomas. Thus, we suggest that immunizations with these enzymes could contribute to the reduction of schistosomiasis transmission, besides being important in immunopathogenesis control of the disease.