Antiproliferative activity of pristimerin isolated from Maytenus ilicifolia (Celastraceae) in human HL-60 cells

Pristimerin has been shown to be cytotoxic to several cancer cell lines. In the present work, the cytotoxicity of pristimerin was evaluated in human tumor cell lines and in human peripheral blood mononuclear cells (PBMC). This work also examined the effects of pristimerin (0.4; 0.8 and 1.7 mu M) in HL-60 cells, after 6, 12 and 24 h of exposure. Pristimerin reduced the number of viable cells and increased number of non-viable cells in a concentration-dependent manner by tripan blue test showing morphological changes consistent with apoptosis. Nevertheless, pristimerin was not selective to cancer cells, since it inhibited PBMC proliferation with an IC50 of 0.88 PM. DNA synthesis inhibition assessed by 5-bromo-2'-deoxyuridine (BrdU) incorporation in HL-60 cells was 70% and 83% for the concentrations of 0.4 and 0.8 mu M, respectively. Pristimerin (10 and 20 mu M) was not able to inhibit topoisomerase 1. In AO/EB (acridine orange/ethidium bromide) staining, all tested concentrations reduced the number of HL-60 viable cells, with the occurrence of necrosis and apoptosis in a concentration-dependent manner, results in agreement with trypan blue exclusion findings. The analysis of membrane integrity and internucleosomal DNA fragmentation by flow cytometry in the presence of pristimerin indicated that treated cells underwent apoptosis. The present data point to the importance of pristimerin as representative of an emerging class of potential anticancer chemicals, exhibiting an antiproliferative effect by inhibiting DNA synthesis and triggering apoptosis. (c) 2008 Elsevier Ltd. All rights reserved.

Xylarenones C-E from an Endophytic Fungus Isolated from Alibertia macrophylla

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Complete Assignments of ¹H and 13C-NMR Spectra of the 3,4-seco-Triterpene Canaric Acid isolated from Rudgea jasminoides

O ácido canárico 1 foi isolado das folhas de Rudgea jasminoides. A substância isolada é um derivado triterpênico do tipo seco-lupano e teve sua estrutura elucidada com base nos dados espectrais, principalmente em experimentos de RMN a 1D e 2D. O sitosterol, o estigmasterol e os ácidos ursólico e oleanólico também foram isolados.

Anti-angiogenic effects of pterogynidine alkaloid isolated from Alchornea glandulosa

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Biodegradation of oil refinery residues using mixed-culture of microorganisms isolated from a landfarming

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Inhibitory activity of compounds isolated from Polymnia sonchifolia on aflatoxin production by Aspergillus flavus

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)