Natural Products fromGarcinia brasiliensisasLeishmaniaProtease Inhibitors

Abstract

The growing list of drug-resistant microorganisms and the persistence of deaths due to diarrhea are compelling reasons to study plants in search of new therapeutic agents. The chemical constitution and popular use of the edible fruits of Campomanesia xanthocarpa O. Berg motivated this study to assess the antimicrobial and antidiarrheal properties of the fruits. An extract in 70% ethanol was prepared, and its antimicrobial activity was tested against several strains of bacteria by the agar diffusion and microdilution methods. Antidiarrheal activity was analyzed by testing intestinal motility in an animal model. Preliminary phytochemical study indicated the presence of flavonoids, saponins, and tannins in the hydroalcoholic extract. Antimicrobial activity was significant, but the minimum inhibitory concentration proved to be higher than the maximum extract concentration tested. The extract did not show significant activity for intestinal motility. Although this fruit extract did not show great results as an antimicrobial or antidiarrheal agent, the study contributes to the search for new plant agents and could be referred to as a research protocol by investigators in this area.

Immunocytochemistry of Proteases in the Study of Leishmania Physiology and Host-Parasite Interaction

“…So, they are considered important targets in Leishmania. Furthermore, specific protease inhibitors induced important alterations in parasite morphology, reduced the viability and growth of Leishmania and killed axenic promastigotes and amastigotes and intracellular amastigotes thus becoming a promising candidate for leishmaniasis treatment (Silva-López et al, 2007;Valdivieso et al, 2010;Olivier & Hassani, 2010;Pereira et al, 2011). In conclusion, immunocytochemical strategies contributed and continue to contribute for the specific identification of targets in Leishmania which is a rational approach for drug development in the leishmaniasis treatment.…”

“…Inhibitors of different types occur commonly among living organisms and viruses, which stresses their ultimate role in physiological processes (Otlewski et al, 1999;Krowarsch et al, 2003;Silva-López, 2009). These inhibitors are valuable tools for investigation of the biochemical properties and the biological functions of proteases, besides they are employed in the treatment of many diseases and are under investigation as chemotheraphic in the treatment of leishmaniasis (Silva-López et al, 2007;Valdivieso et al, 2010;Olivier and Hassani, 2010;Pereira et al, 2011).…”

“…Some of these synthetic and natural products that inhibited specifically crucial steps in a metabolic pathway of Leishmania inducing the parasite death and reducing leishmaniatic lesion progression in susceptible animal models have been tested in controlled clinical trials. These compounds have showed different degrees of efficacy, therapeutic index and in general caused less adverse effects than that observed in patients treated with antimonials or with the second-line drugs that is currently being used for leishmaniasis treatment (Fernandes Rodrigues et al, 2008;Valdivieso et al, 2010;Almeida and Santos, 2011;Pereira et al, 2011). .…”

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

“…Hexane eluates of several plant species from the Amazon region have shown anti-parasitic activities against Leishmania promastigotes; these include Annona foetida (20) , Garcinia brasiliensis (21) , and Lacistema pubescens (22) against L. amazonensis, Gustavia elliptica against L. braziliensis (23) , and Guarea kunthiana and Casearia sylvestris against L. donovani (24) .…”

Synthesis of 1,2,3-Triazole Derivatives of 4,4’-Dihydroxybenzophenone and Evaluation of Their Elastase Inhibitory Activity

“…The 1,2,3-triazole functionality has gained tremendous interest of numerous researchers, since compounds containing this structural motif exhibits several biological activities, such as antituberculosis, 18 anticancer, Our research group has been involved in investigating several synthetic [33][34][35][36][37] and natural 38 benzophenones. For instance, the anti-inflammatory potential of 2,2',4-trihydroxybenzophenone was assessed by means of the rat-paw-edema induced by carrageenan application assay.…”