RESUMO
Anti-inflammatory agents are widely used for the treatment of inflammatory diseases. Nevertheless, the associated side effects of the available drugs make it necessary to search for new anti-inflammatory drugs. Here, we investigated the anti-inflammatory activity of solidagenone. Initially, we observed that a single dose of 30, 60, or 90 mg/kg of solidagenone did not result in mortality or elicit any discernible signs of toxicity in mice. At the same doses, solidagenone promoted a significant reduction in the migration of neutrophils in an acute peritonitis model and decreased mortality in a lipopolysaccharide-induced endotoxic shock model. Interestingly, treatment with solidagenone conferred a protective effect against leukopenia and thrombocytopenia, hematological disorders commonly observed in sepsis conditions. In addition, treatment with all the doses of solidagenone promoted a significant reduction in nitric oxide, TNF-α, and IL-1ß levels relative to the LPS-stimulated vehicle-treated cultures. Furthermore, gene expression and in silico analyses also supported the modulation of the NF-κB pathway by solidagenone. Finally, in silico pharmacokinetics predictions indicated a favorable drugability profile for solidagenone. Taken together, the findings of the present investigation show that solidagenone exhibits significant anti-inflammatory properties in acute experimental models, potentially through the modulation of the NF-κB signaling pathway.
RESUMO
BACKGROUND: The current treatment of Chagas disease, endemic in Latin America and emerging in several countries, is limited by the frequent side effects and variable efficacy of benznidazole. Natural products are an important source for the search for new drugs. AIM/HYPOTHESIS: Considering the great potential of natural products as antiparasitic agents, we investigated the anti-Trypanosoma cruzi activity of a concentrated ethanolic extract of Physalis angulata (EEPA). METHODS: Cytotoxicity to mammalian cells was determined using mouse peritoneal macrophages. The antiparasitic activity was evaluated against axenic epimastigote and bloodstream trypomastigote forms of T. cruzi, and against amastigote forms using T. cruzi-infected macrophages. Cell death mechanism was determined in trypomastigotes by flow cytometry analysis after annexin V and propidium iodide staining. The efficacy of EEPA was examined in vivo in an acute model of infection by monitoring blood parasitaemia and survival rate 30 days after treatment. The effect against trypomastigotes of EEPA and benznidazole acting in combination was evaluated. RESULTS: EEPA effectively inhibits the epimastigote growth (IC50 2.9 ± 0.1 µM) and reduces bloodstream trypomastigote viability (EC50 1.7 ± 0.5 µM). It causes parasite cell death by necrosis. EEPA impairs parasite infectivity as well as amastigote development in concentrations noncytotoxic to mammalian cells. In mice acutely-infected with T. cruzi, EEPA reduced the blood parasitaemia in 72.7%. When combined with benznidazole, EEPA showed a synergistic anti-T. cruzi activity, displaying CI values of 0.8 ± 0.07 at EC50 and 0.83 ± 0.1 at EC90. CONCLUSION: EEPA has antiparasitic activity against T. cruzi, causing cell death by necrosis and showing synergistic activity with benznidazole. These findings were reinforced by the observed efficacy of EEPA in reducing parasite load in T. cruzi-mice. Therefore, this represents an important source of antiparasitic natural products.