In vitro and in vivo assessment of the anti-malarial activity of Caesalpinia pluviosa

• Published in: Malaria journal 2011-05, Vol.10 (1), p.112-112, Article 112
• Main Authors: Kayano, Ana Carolina A V, Lopes, Stefanie C P, Bueno, Fernanda G, Cabral, Elaine C, Souza-Neiras, Wanessa C, Yamauchi, Lucy M, Foglio, Mary A, Eberlin, Marcos N, Mello, João Carlos P, Costa, Fabio T M
• Format: Article
• Language: English
• Subjects: Animals; Antimalarials - administration & dosage; Antimalarials - isolation & purification; Antimalarials - pharmacology; Antimalarials - toxicity; Artemisinins - pharmacology; Artesunate; Bark; Blood; Brazil; Caesalpinia; Caesalpinia - chemistry; Cell Line; Cell Survival - drug effects; Chloroquine; Cytotoxicity; Disease Models, Animal; Drug interaction; Drug interactions; Drug resistance; Drug Synergism; Drug therapy; Drugs; Erythrocytes; Humans; Malaria; Malaria - drug therapy; Malaria - parasitology; Mass spectrometry; Mass spectroscopy; Medicinal plants; Mice; Mice, Inbred C57BL; Parasites; Physiological aspects; Plant Bark - chemistry; Plant Extracts - administration & dosage; Plant Extracts - isolation & purification; Plant Extracts - pharmacology; Plant Extracts - toxicity; Plants, Medicinal - chemistry; Plasmodium chabaudi - drug effects; Plasmodium falciparum; Plasmodium falciparum - drug effects; Purification; Quercetin; Quercetin - administration & dosage; Quercetin - isolation & purification; Quercetin - pharmacology; Quercetin - toxicity; Rodent Diseases - drug therapy; Rodent Diseases - parasitology; Water purification
• ISSN: 1475-2875; 1475-2875
• DOI: 10.1186/1475-2875-10-112

To overcome the problem of increasing drug resistance, traditional medicines are an important source for potential new anti-malarials. Caesalpinia pluviosa, commonly named "sibipiruna", originates from Brazil and possess multiple therapeutic properties, including anti-malarial activity. Crude extract (CE) was obtained from stem bark by purification using different solvents, resulting in seven fractions. An MTT assay was performed to evaluate cytotoxicity in MCF-7 cells. The CE and its fractions were tested in vitro against chloroquine-sensitive (3D7) and -resistant (S20) strains of Plasmodium falciparum and in vivo in Plasmodium chabaudi-infected mice. In vitro interaction with artesunate and the active C. pluviosa fractions was assessed, and mass spectrometry analyses were conducted. At non-toxic concentrations, the 100% ethanolic (F4) and 50% methanolic (F5) fractions possessed significant anti-malarial activity against both 3D7 and S20 strains. Drug interaction assays with artesunate showed a synergistic interaction with the F4. Four days of treatment with this fraction significantly inhibited parasitaemia in mice in a dose-dependent manner. Mass spectrometry analyses revealed the presence of an ion corresponding to m/z 303.0450, suggesting the presence of quercetin. However, a second set of analyses, with a quercetin standard, showed distinct ions of m/z 137 and 153. The findings show that the F4 fraction of C. pluviosa exhibits anti-malarial activity in vitro at non-toxic concentrations, which was potentiated in the presence of artesunate. Moreover, this anti-malarial activity was also sustained in vivo after treatment of infected mice. Finally, mass spectrometry analyses suggest that a new compound, most likely an isomer of quercetin, is responsible for the anti-malarial activity of the F4.