Antiplasmodial and antileishmanial activities of compounds from Piper tuberculatum Jacq fruits

Abstract INTRODUCTION This study assessed the activity of compounds from Piper tuberculatum against Plasmodium falciparum and Leishmania guyanensis. METHODS The effects of compounds from P. tuberculatum fruits on P. falciparum and L. guyanensis promastigote growth in vitro were determined. Hemolytic action and cytotoxicity in HepG2 and J774 cells were measured. RESULTS Three compounds showed strong antiplasmodial activity and one compound showed strong antileishmanial activity. Two compounds were non-toxic to HepG2 cells and all were toxic to J774 cells. The compounds showed no hemolytic activity. CONCLUSIONS The tested compounds from P. tuberculatum exhibited antiparasitic and cytotoxic effects.

Screening of the in vitro antileishmanial activities of compounds and secondary metabolites isolated from Maytenus guianensis Klotzsch ex Reissek (Celastraceae) chichuá Amazon

Abstract INTRODUCTION Maytenus guianensis is a member of the Celastraceae family that is used in traditional medicine, particularly for its anti-parasitic and anti-cancer effects. To explore the ethnopharmacological potential of this plant, the present study was designed to screen the in vitro antileishmanial activities of extracts and compounds isolated from M. guianensis. METHODS Maytenus guianensis stems and leaves were extracted in acetone, followed by the preparation of eluates and isolation of secondary metabolites using chromatography on a glass column with silica gel as the fixed phase. The chemical components were identified using spectroscopic methods, including one- and two-dimensional nuclear magnetic resonance of hydrogen-1 and carbon-13, mass spectroscopy, and infrared spectroscopy. The anti-Leishmania amazonensis activities of these eluates and compounds were evaluated by direct promastigote counting and viability assays. RESULTS It was found that the hexane bark eluate produced the strongest anti-L. amazonensis effect, with 90-100% inhibition of the promastigote form. The isolated metabolite that produced the best result was tingenone B, followed by a compound formed by the union of tingenone and tingenone B (80-90% inhibition). CONCLUSIONS Maytenus guianensis shows anti-parasite activity that warrants further investigation to determine the mechanisms underlying this antileishmanial effect and to evaluate the pharmacological potential of these eluates and isolated secondary metabolites, while minimizing any adverse effects.

Antimalarial ethnopharmacology in the Brazilian Amazon / Etnofarmacologia antimalárica na Amazônia Brasileira

The preoccupation to find new drugs for the treatment of malaria is increasing steadily due to the resistance of the parasite, which is a threat to disease control, The present study describes a literature review on the antimalarial ethnopharmacology (Anti-Plasmodium falciparum - in vitro) of the Brazilian Amazon plants, It was found a great diversity of plant species in the Brazilian Amazon with potential for research of new herbal and secondary metabolites with antiplasmodial action, in addition to treating other neglected parasitic diseases, However, for these studies is needed in addition to financial support, the interaction between different laboratories and research groups for the formation of multidisciplinary and interdisciplinary teams, which will enhance the research level in the region and increase the likelihood of new antimalarial drugs discovery...

Está cada vez maior a necessidade em se buscar novos fármacos para o tratamento da malária, principalmente devido à resistência do parasito, o que é uma ameaça ao controle da doença. O presente estudo descreve uma revisão bibliográfica sobre a etnofarmacologia antimalárica (Anti-Plasmodium falciparum - in vitro) de plantas da Amazônia brasileira. Constatou-se uma grande diversidade de espécies vegetais na Amazônia brasileira com potencial para a investigação de novos fitoterápicos e metabólitos secundários com ação antiplasmodial, além do tratamento de outras parasitoses negligenciadas. Porém, para a realização desses estudos são necessários além de apoio financeiro, a interação entre diferentes laboratórios e grupos de pesquisa para a formação de equipes multidisciplinares e interdisciplinares, o que irá potencializar o nível da pesquisa na região e aumentar a probabilidade de descoberta de novos fármacos antimaláricos...

Acute genotoxicity analysis in vivo of the aqueous extract of Maytenus guyanensis Amazonian chichuá

Abstract The species Maytenus guyanensis Klotzsch ex Reissek, Celastraceae, present a wide variety of possible pharmacological activities and its roots and stems are used by popular medicine in the western Amazon rainforest. Few studies have demonstrated the genotoxic safety of the popular use of this species, and owing to this, the present study aimed to perform an analysis of the acute genotoxicity in vivo of the aqueous extract of M. guyanensis. Male and female mice from Mus musculus species, of weights ranging from 20 to 40 g, organized in eight groups with different treatments were used. The aqueous extracts of the bark of M. guyanensis were administered orally by gavage with 0.1 ml of the test substance per 10 g of the animal, followed by performance of comet assay in peripheral blood, PCE/NCE correlation and occurrence of micronuclei in the bone marrow. It was found that the aqueous extract of M. guyanensis, with ten times higher concentration than those used in ethnopharmacology, did not present genotoxic effect and, moreover, it has antigenotoxic action in mice treated acutely. Further studies regarding bioaccumulation and chronic effects of this species are suggested, in order to improve the understanding of its mechanism of action, ensuring the efficacy and safety of its utilization and developing phytotherapics and drugs.