In vivo and in vitro evaluation of the antimalarial activity of Caesalpinia pluviosa and its active fraction analysis

Author(s)

Ana Carolina Andrade Vitor Kayano

• Document type: Master's Dissertation
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Instituto de Biologia
• Defense date: 2011-03-03

Examining board members

Fabio Trindade Maranhão Costa; Alessandro dos Santos Farias; João Ernesto de Carvalho

• Advisor: Fabio Trindade Maranhão Costa

Abstract

To overcome the problem of increasing drug resistance traditional medicines are an important source for investigation of potential new antimalarials. Caesalpinia pluviosa, commonly named 'sibipiruna', is originated from Brazil and studies showed that this genus present multiple therapeutic properties, including antimalarial activity. Crude extract obtained from stem bark was purified with different solvents, resulting in seven fractions. MTT assay was performed to evaluate cytotoxicity in MCF-7 cells. The crude extract and its fractions were tested in vitro against chloroquine-sensitive (3D7) and -resistant (S20) strains of Plasmodium falciparum and in vivo in P. chabaudi-infected mice. In vitro interaction with artesunate and C. pluviosa fraction was assessed and mass spectrometry analyses were conducted. At non-toxic concentrations the 100% ethanolic and 50% methanolic fractions presented significant antimalarial activity against both 3D7 and S20 strains, and drug interaction assays with artesunate showed a synergistic effect with 100% ethanolic fraction. This fraction was able to inhibit mice parasitemia significantly and in a dose dependent manner after 4 days treatment (0-3 post-infection). Moreover, 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 the standard quercetin, showed distinct ions of m/z 137 and 153. Our findings show that the 100% ethanolic fraction of C. pluviosa exhibited antimalarial activity in vitro at non-toxic concentrations and this effect was potentiated with the presence of artesunate. Moreover, this antimalarial activity was also sustained in vivo after treatment of infected mice. Finally, mass spectrometry analyses suggest a new compound, most likely an isomer of quercetin, related with antimalarial activity of the 100% ethanolic fraction (AU)

• FAPESP's process: 09/01619-9 - In vitro and in vivo assessment of antimalarial activity of Caesalpinia pluviosa and analysis of its active fractions
• Grantee: Ana Carolina Andrade Vitor Kayano
• Support Opportunities: Scholarships in Brazil - Master