RESUMEN
Arthropod-borne viruses within the Flaviviridae family such as Zika (ZIKV) and dengue (DENV) are responsible for major outbreaks in tropical countries, and there are no specific treatments against them. Naringenin and 7-O-methyl naringenin are flavonoids that can be extracted from geopropolis, a natural material that the Brazilian Jandaira stingless bee (Melipona subnitida Ducke) produces to protect its nest. Here, these flavonoids were tested against ZIKV and DENV using Vero cells as a cellular model to perform a cytotoxicity assay and to define the effective concentrations of TCID50 as the readout method. The results demonstrated the antiviral activity of the compounds against both viruses upon the treatment of infected cells. The tested flavonoids had antiviral activity comparable with 6-methylmercaptopurine riboside (6-MMPr), used here as a positive control. In addition, to identify the possible action mechanism of the antiviral candidates, we carried out a docking analysis followed by a molecular dynamics simulation to elucidate naringenin and 7-O-methyl naringenin binding sites to each virus. Altogether, these results demonstrate that both flavonoids have potent antiviral effects against both viruses and warrant further in vivo trials.
RESUMEN
Hyperuricemia, the metabolic alteration that leads to gout or gouty arthritis, is increasing worldwide. Glycoconjugated triazole-phthalimides show potent anti-inflammatory activity. The aim of this study was to evaluate the anti-hyperuricemia effect of glycoconjugated triazole-phthalimides. To develop hyperuricemia, groups of mice received orally potassium oxonate (250 mg/kg) for 7 days, and F2, F3 and F4 glycoconjugated triazole-phthalimides (20 mg/kg), allopurinol (300 mg/kg), and 1% carboxymethylcellulose; indomethacin (2 and 4 mg/kg) was the positive control for anti-arthritic effect. Genotoxic and mutagenic effects were evaluated by the comet and micronucleus assays, respectively. The hemolytic action of the compounds was evaluated. Phthalimides F2, F3 and F4 significantly reduced the levels of serum uric acid, creatinine and urea in hyperuricemic animals. In addition, the compounds were efficient in reducing protein denaturation in a dose-dependent manner. In an interesting way, the histopathological analysis of kidneys from groups treated with F2, F3 and F4 showed a glomerular architecture, with the Bowman's capsule and renal tubules having a normal appearance and without inflammatory changes. Also, F2 and F4 showed a small increase in micronuclei, indicating a low mutagenic effect, whilst by comet assay only, we could infer that F4 affected the frequency and damage index, thus indicating a very small genotoxic action. Similarly, the phthalimides showed a low degree of erythrocyte hemolysis (<3%). Our data demonstrate that the new glycoconjugate triazole-phthalimides have potential to treat hyperuricemia and its secondary complications, such as gouty arthritis, with a low to non-significant rate of erythrocytes hemolysis, genotoxicity and mutagenicity making these molecules strong candidates as pharmaceutical agents for treatment requiring uric-acid-lowering therapy.
RESUMEN
Organic compounds obtained by click chemistry reactions have demonstrated a broad spectrum of biological activities being widely applied for the development of molecules against pathogens of medical and veterinary importance. Cutaneous leishmaniasis (CL), caused by intracellular protozoa parasite of genus Leishmania, comprises a complex of clinical manifestations that affect the skin and mucous membranes. The available drugs for the treatment are toxic and costly, with long periods of treatment, and the emergence of resistant strains has been reported. In this study we investigated the in vitro effects of a phthalimide-1,2,3-triazole derivative, the 4-Phenyl-1-[2-(phthalimido-2-yl)ethyl]-1H-1,2,3-triazole (PT4) obtained by click chemistry, on mammalian cells and on L. amazonensis and L. braziliensis, the causative agents of CL in Brazil. In silico ADMET evaluation of PT4 showed that this molecule has good pharmacokinetic properties with no violation of Lipinski's rules. The in vitro assays showed that PT4 was more selective for both Leishmania species than to mammalian cells. This compound also presented low cytotoxicity to mammalian cells with CC50 > 500 µM. Treatment of promastigote forms with different concentrations of PT4 resulted in ultrastructural alterations, such as plasma membrane wrinkling, shortening of cell body, increased cell volume and cell rupture. The molecular dynamic simulations showed that PT4 interacts with Lanosterol 14 α-demethylase from Leishmania, an essential enzyme of lipid synthesis pathway in this parasite. Our results demonstrated PT4 was effective against both species of Leishmania. PT4 caused a decrease of mitochondrial membrane potential and increased production of reactive oxygen species, which may lead to parasite death. Taken together, our results pointed PT4 as promissing therapeutic agent against CL.