Chemical Characterization and Leishmanicidal Activity In Vitro and In Silico of Natural Products Obtained from Leaves of Vernonanthura brasiliana (L.) H. Rob (Asteraceae).

Vernonanthura brasiliana (L.) H. Rob is a medicinal plant used for the treatment of several infections. This study aimed to evaluate the antileishmanial activity of V. brasiliana leaves using in vitro and in silico approaches. The chemical composition of V. brasiliana leaf extract was determined through liquid chromatography-mass spectrometry (LC-MS). The inhibitory activity against Leishmania amazonensis promastigote was evaluated by the MTT method. In silico analysis was performed using Lanosterol 14alpha-demethylase (CYP51) as the target. The toxicity analysis was performed in RAW 264.7 cells and Tenebrio molitor larvae. LC-MS revealed the presence of 14 compounds in V. brasiliana crude extract, including flavonoids, flavones, sesquiterpene lactones, and quinic acids. Eriodictol (ΔGbind = -9.0), luteolin (ΔGbind = -8.7), and apigenin (ΔGbind = -8.6) obtained greater strength of molecular interaction with lanosterol demethylase in the molecular docking study. The hexane fraction of V. brasiliana showed the best leishmanicidal activity against L. amazonensis in vitro (IC50 12.44 ± 0.875 µg·mL-1) and low cytotoxicity in RAW 264.7 cells (CC50 314.89 µg·mL-1, SI = 25.30) and T. molitor larvae. However, the hexane fraction and Amphotericin-B had antagonistic interaction (FICI index ≥ 4.0). This study revealed that V. brasiliana and its metabolites are potential sources of lead compounds for drugs for leishmaniasis treatment.

Parasitological and histological aspects of Holochilus sciureus naturally infected by Schistosoma mansoni / Aspectos parasitológicos e histológicos de Holochilus sciureus naturalmente infectados por Schistosoma mansoni

Abstract Schistosomiasis is a neglected disease that affects millions of people around the world, being common in the state of Maranhão. A total of 225 rodents of the Holochilus sciureus species from the Western Lowland Maranhão were studied, of which 144 animals (64%) exhibited Schistosoma eggs in their feces samples. Macroscopic lesions characterized as well-defined whitish areas on the liver and spleen surfaces were observed. Histopathological examination revealed multifocal granulomas in the esophagus, liver, spleen, pancreas and duodenum, with structures compatible with Schistosoma mansoni eggs, as well as severe hepatic micro-vacuolar degeneration, multifocal and coalescent, with proliferation of random bile ducts and associated epithelial hyperplasia to areas of fibrosis. Adult forms of the parasite were observed in the blood vessels of the portal space. The lungs exhibited moderate and diffuse interstitial pneumonia with intralesional S. mansoni eggs. In the kidneys, hyaline cylinders were observed in the pelvis and diffuse hemorrhage. In conclusion, H. sciureus displays a pathological picture similar to human being. This rodent plays a role as sentinel in Baixada Maranhense.

Resumo A esquistossomose é uma doença negligenciada que afeta milhões de pessoas em todo o mundo, sendo comum no estado do Maranhão. Um total de 225 roedores da espécie Holochilus sciureus da Planície Ocidental do Maranhão foram estudados, dos quais 144 animais (64%) apresentaram ovos de Schistosoma em suas fezes. Lesões macroscópicas caracterizadas como áreas esbranquiçadas bem definidas nas superfícies do fígado e baço foram observadas. O exame histopatológico revelou granulomas multifocais no esôfago, fígado, baço, pâncreas e duodeno, com estruturas compatíveis com ovos de Schistosoma mansoni, degeneração micro-vacuolar hepática grave, multifocal e coalescente, com proliferação de ductos biliares aleatórios e hiperplasia epitelial associada a áreas de fibrose. Formas adultas do parasito foram observadas nos vasos sanguíneos do espaço portal. Os pulmões exibiram pneumonia intersticial moderada e difusa com ovos de S. mansoni intralesionais. Nos rins, foram observados cilindros hialinos na pelve e hemorragia difusa. Em conclusão, H. sciureus apresenta um quadro patológico semelhante ao ser humano. Este roedor desempenha um papel de sentinela na Baixada Maranhense.

Parasitological and histological aspects of Holochilus sciureus naturally infected by Schistosoma mansoni.

Schistosomiasis is a neglected disease that affects millions of people around the world, being common in the state of Maranhão. A total of 225 rodents of the Holochilus sciureus species from the Western Lowland Maranhão were studied, of which 144 animals (64%) exhibited Schistosoma eggs in their feces samples. Macroscopic lesions characterized as well-defined whitish areas on the liver and spleen surfaces were observed. Histopathological examination revealed multifocal granulomas in the esophagus, liver, spleen, pancreas and duodenum, with structures compatible with Schistosoma mansoni eggs, as well as severe hepatic micro-vacuolar degeneration, multifocal and coalescent, with proliferation of random bile ducts and associated epithelial hyperplasia to areas of fibrosis. Adult forms of the parasite were observed in the blood vessels of the portal space. The lungs exhibited moderate and diffuse interstitial pneumonia with intralesional S. mansoni eggs. In the kidneys, hyaline cylinders were observed in the pelvis and diffuse hemorrhage. In conclusion, H. sciureus displays a pathological picture similar to human being. This rodent plays a role as sentinel in Baixada Maranhense.