Ação antiproliferativado flavonoide morina e do extrato da folha de oliveira (Oleaeuropaea L. ) contra a linhagem de célula H460 / The antiproliferative action of morin flavonoid and olive leaf extract (Olea europaea L. ) against the cell line H460

RESUMO O presente estudo investigou a indução de morte celular por apoptose pelo flavonóide morina e pelo extrato da folha de oliveira (Oleaeuropaea L.) em linhagens de células de câncer de pulmão do tipo não pequenas (H460). O tratamento com morina e o extrato de oliveira em células H460 resultou na redução do crescimento tumoral e indução de morte celular avaliados pelos ensaios de MTT e lactato desidrogenase (LDH) e a morte celular por apoptose confirmada por microscopia de fluorescência e análise por citometria de fluxo. Os dados indicaram que o flavonóide morina e o extrato de oliveira diminuíram a viabilidade celular para taxas percentuais de 7,22± 1,54% e 62,37± 2,85% nas concentrações de 800µM e µg/mL, respectivamente. As maiores taxas percentuais de morte celular por apoptose foram100% para morina na concentração de 800µM e 70,49 ± 5,91% para o extrato de oliveira na concentração de 800 µg/mL. Estes resultados foram associados com a alteração do potencial de membrana mitocondrial, cujos valores são de 54,91% para morina na concentração de 400µM e 42,2% para o extrato de oliveira na concentração de 800 µg/mL sugerindo envolvimento da via intrínseca da morte celular por apoptose. Portanto, morina e o extrato de oliveira afetaram a viabilidade celular da linhagem H460 induzindo morte celular por apoptose.

ABSTRACT This study investigates possible apoptosis induction mechanism by the flavonoid morin and the olive leaf extract (Olea europaea L.) in non-small lung cancer cells (H460). The treatment with morin and olive leaves extract resulted in growth inhibition and induction of apoptosis in H460 cells lines measured by the MTT assay methods and confirmed by fluorescence microscopy, flow cytometry analysis. The data indicated that themurin and the extract of olive decreased the cell viability percentage rates of 7.22 ± 1,54% and 62.37 ± 2,85% in the concentrations of 800 µM and µg/mL, respectively. The highest percentage rates of cell death by apoptosis were 100% for themorin in a concentration of 800 µM and 70.49 ± 5.91% for the olive extract in a concentration of 800 µg/mL. These findings were associated with altered mitochondrial membrane potential, whose value is 54.91% for the murin concentration of 400 µM and 42.2% for the olive extract in a concentration of 800 mg / mL, suggesting involvement of the intrinsic pathway of cell death by apoptosis. Therefore, the morin and the olive extract affect the cell viability of H460 cell lines inducing cell death by apoptosis.

Two related thrombin-like enzymes present in Bothrops atrox venom

This article describes the presence of two new forms of a thrombin-like enzyme, both with apparent molecular masses of 38 kDa, in Bothrops atrox venom. Both share the ability to cleave fibrinogen into fibrin and to digest casein. Both present identical Km on the substrate BApNA. Their N-terminal amino acid sequences are identical for 26 residues, sharing 80 percent homology with batroxobin and flavoxobin. Two groups of monoclonal antibodies (mAbs) raised against the purified enzyme forms recognized different epitopes of the putative corresponding enzymes present in B. atrox crude venom. On Western blotting analysis of B. atrox crude venom, mAbs 5DB2C8, 5AA10 and 5CF11, but not mAbs 6CC5 and 6AD2-G5, revealed two or more protein bands ranging from 25 to 38 kDa. By immunoprecipitation assays, the 6AD2-G5 mAb was able to precipitate protein bands of 36-38 kDa from B. atrox, B. leucurus, B. pradoi, B. moojeni, B. jararaca and B. neuwiedii crude venoms. Fibrinogen-clotting activity was inhibited when the same venom specimens were pre-incubated with mAb 6AD2-G5, except for B. jararaca and B. neuwiedii