Antimalarial activity of compounds and mixed fractions of Cecropia pachystachya

Abstract

Extracts from Cecropia pachystachya (Cecropiaceae), a medicinal plant used in Brazil, were tested for their antimalarial activity against Plasmodium falciparum and/or Plasmodium berghei in mice. The ethanol extracts of wood, root, and leaves reduce parasitemia of malaria-infected mice from 35-66% in relation to nontreated control mice. The plant roots extracts, with stronger activity, were further analyzed and provided subfractions also active in vivo from which two compounds were isolated and chemically characterized as b-sitosterol and tormentic acid. Although both compounds were active in mice malaria, only the tormentic acid inhibited P. falciparum chloroquine-resistant parasites (W2) growth in cultures, reducing parasitemia dose-responsively (IC 50 5 11-15 mg/ml). The antimalarial activity of the plant extracts kept refrigerated 7 years after the initial isolation, when tested in parallel with new extracts freshly isolated from plants collected at the same geographical site, was similar, confirming the superiority of the plant roots and the stability of the active extracts. In these experiments, inhibition of parasite growth was measured by hypoxanthine incorporation and by immunoenzymatic assay (ELISA) with monoclonal antibodies against the P. falciparum histidine-rich protein (HRP2), expressed by the erythrocytic forms. The plant roots showed the lowest IC 50 value and displayed the lowest toxicity, thus having the best therapeutic index. C. pachystachya species is therefore a good candidate for phytotherapeutic use against malaria. Further studies are ongoing to isolate new active compounds through bioguided fractionation analysis, in an effort to develop a new drug prototype against P. falciparum erythrocytic parasites. Drug Dev Res 71:82-91, 2010.

Antimalarial Activity of Plant Metabolites

“…The ethanol extracts of the different parts of the plants were evaluated for their activity against P. falciparum in vitro and P. berghei in vivo [40]. The parasitemia of malaria-infected mice was reduced by 35-66% with treatment of the ethanol extracts of the wood, root, and leaf materials in comparison with the non-treated control group.…”

An ethnobotanical study of anti-malarial plants among indigenous people on the upper Negro River in the Brazilian Amazon

“…Extracts of Cecropia pachystachya Trécul (Urticaceae) exhibited 24-66% inhibition in vivo against P. berghei at 250 and 500 mg/kg/day. β-sitosterol & tormentic acid from the roots of this species suppressed P. berghei in vivo by 58 and 51%, respectively, at 15 mg/kg/day, and by 35 and 20%, respectively, at 10 mg/kg/day(Uchoa et al, 2010).Carrapicho (Acanthospermum spp.) is an anti-malarial herb used in much of the BrazilianAmazon.…”

Cecropia peltataAccumulates Starch or Soluble Glycogen by Differentially Regulating Starch Biosynthetic Genes

“…Our initial functional analysis revealed several metabolic pathways differentially regulated between leaves and MBs, but further mining of our transcriptome and proteome data sets might shed light into these processes. These resources might also aid in the investigation of C. peltata as a potential source of biomedicines for the treatment of rheumatism, malaria, and diabetes (Pérez-Guerrero et al, 2001;Andrade-Cetto and Heinrich, 2005;Uchoa et al, 2010) or facilitate molecular-ecological studies into the mechanisms of ant-plant communication.…”

“…However, there are a few exceptions to this rule, including the fast-growing pioneer tree native to subtropical regions, Cecropia peltata (Fleming and Williams, 1990). C. peltata is known for its invasive nature (www.issg.org), and its leaf extracts are reported to have medicinal properties effective against rheumatism, malaria, and diabetes (Pérez-Guerrero et al, 2001;Andrade-Cetto and Heinrich, 2005;Uchoa et al, 2010). C. peltata has a myrmecophytic lifestyle, sharing a symbiotic relationship with stinging ants (Folgarait et al, 1994;Faveri and Vasconcelos, 2004), which inhabit the hollow trunk and protect the tree against herbivores and competition from vines.…”