Phenolic composition and antiparasitic activity of plants from the Brazilian Northeast “Cerrado”

Abstract

This work describes the antiparasitic and cytotoxic activities of three plant species from the Cerrado biome, Northeastern Brazil. Significant antiparasitic inhibition was observed against Trypanosoma cruzi (63.86%), Leishmania brasiliensis (92.20%) and Leishmania infantum (95.23%) when using ethanol extract from leaves of Guazuma ulmifolia Lam. (Malvaceae), at a concentration of 500 μg/mL. However, low levels of inhibition were observed when assessing leishmanicidal and trypanocidal (Clone CL-B5) activities of crude ethanol extracts from leaves and bast tissue of Luehea paniculata (Malvaceae) and leaves and bark of Prockia crucis (Salicaceae) at a concentration of 500 μg/mL. The extracts revealed the presence of phenolic acids such as gallic acid, chlorogenic acid, caffeic acid and rosmarinic acid, as well as flavonoids such as rutin, luteolin, apigenin and quercetin - the latter detected only in G. ulmifolia. G. ulmifolia extract displayed higher leishmanicidal activity probably due to the presence of quercetin, a potent known leishmanicidal compound. A cytotoxicity test indicated values over 50% at the highest concentration (1000 μg/mL) for all natural products, which were considered cytotoxic. This points out the need for further tests to enable future in vivo trials, including antineoplastic activity on human tumor cells.

Expression profiling of Sudanese visceral leishmaniasis patients pre‐ and post‐treatment with sodium stibogluconate

“…Specifically, we identified the plant‐based flavonoid drug genistein as having potential activity in determining the observed expression profiles in post‐treatment compared to pretreatment samples. This provides some support for the recent resurgence of interest in investigating the leishmanicidal activity of plant‐derived flavonoids. The observation that the quinoline alkaloid camptothecin was a potential upstream regulator was also of interest, especially given the progress of the orally active 8‐aminoquinoline sitamaquine (formerly WR‐6026) through preclinical and phase I/II clinical trials against VL in India, Brazil and Kenya (reviewed Ref.…”

Can the Cure for Chagas’ Disease be Found in Nature?

“…In this way, it is possible to perceive that Trypanosoma cruzi has a very complex biological cycle, involving several species of triatomines, Trypanosomatids in different stages of growth, wild and domestic mammals, and humans [16]. There are different forms of the T. cruzi parasite related to their stage of development: trypomastigote, epimastigote, and amastigote ( Figure 2).…”

“…Searching in the literature, it is possible to find many works about broad classes of secondary metabolites that have proven to be active against T. cruzi [16]. Usually, as part of preliminary investigation, medicinal plant extracts, fractions, isolated natural products, or pure compounds are subjected to chemical characterization tests and in vitro assays for screening their biological activity.…”

“…Furthermore, the presence of phenolic compounds ( Figure 5) like chlorogenic acid (11), rosmarinic acid (12), and coumarin (13) and flavonoids ( Figure 6) luteolin (14), kaempferol (15), and vitexin (16) in low concentrations may have been responsible for the weak bioactivity of L. paniculata and P. crucis ethanolic extracts against T. cruzi [16].…”

“…(Malvaceae), was active in vitro against the tested parasite strains of T. cruzi, L. brasiliensis, and L. infantum, possibly due the presence of quercetin (17), a potent known leishmanicidal flavonoid from flavones group [16]. The cytotoxicity presented by the aforementioned extract reinforces the need for further tests, including in vivo trials, like antineoplastic activity in tumor cells, before considerate G. ulmifolia ethanol extracts as a potential alternative source of natural compounds against Chagas' disease.…”