Atividade de constituintes micromoleculares de Renealmia alpinia (Rottb.) Maas (Zingiberaceae) sobre Leishmania (Leishmania) chagasi

AUTOR(ES)
DATA DE PUBLICAÇÃO

2009

RESUMO

Leishmaniasis is a complex of tropical disease caused by protozoa belonging to the genus Leishmania and it is among the six most important endemic diseases in the world. Its clinical manifestations can vary from benign cutaneous injuries to the disfiguring and destructive mucosal lesions or to the visceral form, fatal if not treated. Its incidence has increased for several factors, including co-infection with the HIV which hampers the success of the pharmacotherapy. The currently available treatment includes pentavalent antimony as first choice and the pentamidine and the amphotericin B, as second-line drugs, in addition to the miltefosine, already registered in some countries. However, problems of toxicities and high cost associated to the use of these medicines, beyond resistance cases, limit their use. So,there is an urgent need to find new compounds that provide therapeutics options for the treatment of leishmaniasis. Extracts or compounds from plants can consist in a valuable beginning on search for new therapeutics agents. An in vitro screening previously carried out in our laboratory against promastigotes forms of Leishmania amazonensis identified activity for the hexane extract of Renealmia alpinia leaves, with an IC50 of 40,58 μg/mL. The hexane crude extract of Renealmia alpinia (Rottb.) Maas (Zingiberaceae) leaves and pseudostems was then tested and showed activity against promastigotes forms of Leishmania (Leishmania) chagasi, with IC50 of 22,81 μg/mL. The chemical bioguided fractionation of the crude extract active against Leishmania (Leishmania) chagasi in chromatographic column produced 24 groups, congregated according to anti-Leishmania activity and chromatographic profile in TLC. The D3 group, with IC50 of 19,41 μg/mL, was gotten in greater quantify from a new column and then fractionated. Its fractionation resulted in 26 sub-groups, congregated according to chromatographic profile. Of these, the D3-9 sub-group allowed the isolation of 2,4-dihydroxy- 6-(phenylethene)-methyl benzoate and of 2,4-dihydroxy-6-(phenylethane)-methyl benzoate, elucidated by spectrometric techniques of nuclear magnetic resonance (NMR) (1D) (1H, 13C) e (2D) (COSY, HSQC, HMBC) and infra-red spectroscopy (IR). To the best of our knowledge, 2,4-dihydroxy-6- (phenylethene)-methyl benzoate is unpublished in Renealmia alpinia, in Zingiberaceae family and as natural compound and it was previously gotten by synthesis. Your NMR 13C, COSY, HSQC e HMBC data are unpublished. The compound 2,4- dihydroxy-6-(phenylethane)-methyl benzoate is unpublished in Renealmia alpinia specie, however, it was previously isolated from Boesenbergia rotunda rhizomes (Zingiberaceae) and it was also obtained by synthesis. Your NMR 13C, COSY, HSQC e HMBC data are unpublished. Against Leishmania (Leishmania) chagasi, both compounds showed IC50 >100 μg/mL and, therefore, are not the antileishmanial compounds from the D3-9 subgroup and Renealmia alpinia specie. However, are unpublished in Renealmia alpinia specie, which chemical composition is almost unknown. Other groups and sub-groups proceeding from the crude extract and that had showed activity against Leishmania (Leishmania) chagasi during the study, as AcOEt2, with IC50 of 7,12 μg/mL, D4, with IC50 of 3,08 μg/mL and D3- 11 and D3-16, with IC50 of 12,23 and 15,25 μg/mL remain as promising for new studies in the search for therapeutics options for leishmaniasis control. They are being obtained in larger quantities for further studies.

ASSUNTO(S)

zingiberaceae leishmania (leishmania) chagasi leishmania (leishmania) chagasi leishmaniose triagem tratamento zingiberaceae leishmaniasis renealmia alpinia ciencias da saude renealmia alpinia treatment cerrado cerrado screening

ACESSO AO ARTIGO

Documentos Relacionados