Navegando por Autor "Moura, Raniere M."
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Artigo CvL, a lectin from the marine sponge Cliona varians: Isolation, characterization and its effects on pathogenic bacteria and Leishmania promastigotes(Elsevier, 2006) Queiroz, Alexandre F.S.; Moura, Raniere M.; Fook, Jacy M.S.L.L.; Dias, Anny S.F.; Monteiro, Norberto K.V.; Ribeiro, Jannisson K.C.; Moura, Gioconda E.D.D.; Macedo, Leonardo L.P.; Santos, Elizeu A.; Sales, Maurício P.CvL, a lectin from the marine sponge Cliona varians was purified by acetone fractionation followed by Sepharose CL 4B affinity chromatography. CvL agglutinated papainized treated human erythrocytes with preference for type A erythrocytes. The lectin was strongly inhibited by monosaccharide D-galactose and disaccharide sucrose. CvL is a tetrameric glycoprotein of 28 kDa subunits linked by disulphide bridges with a molecular mass of 106 kDa by SDS-PAGE and 114 kDa by Sephacryl S300 gel filtration. The lectin was Ca2+ dependent, stable up to 60 °C for 60 min, with optimum pH of 7.5. CvL displays a cytotoxic effect on gram positive bacteria, such as Bacillus subtilis and Staphylococcus aureus. However, CvL did not affect gram negative bacteria, such as Escherichia coli and Pseudomonas aeruginosa. Leishmania chagasi promastigotes were agglutinated by CvL up to 28 titer. These findings are indicative of the physiological defense roles of CvL and its possible use in the antibiosis of bacteria and protozoa pathogenic.Artigo Effect of trypsin inhibitor from Crotalaria pallida seeds on Callosobruchus maculatus (cowpea weevil) and Ceratitis capitata (fruit fly)(Plant Physiology and Biochemistry, 2005-12-07) Gomes, Carlos E. M.; Barbosa, Aulus E. A. D.; Macedo, Leonardo L. P.; Pitanga, Joelma C. M.; Moura, Fabiano T.; Oliveira, Adeliana S.; Moura, Raniere M.; Queiroz, Alexandre F. S.; Macedo, Francisco P.; Andrade, Lúcia B. S.; Vidal, Márcia S.; Sales, Mauricio P.Artigo Growth inhibitory activity of a novel lectin from Cliona varians against K562 human erythroleukemia cells(Springer, 2008-09-10) Queiroz, Alexandre Flavio Silva de; Silva, Rodrigo A.; Moura, Raniere M.; Dreyfuss, Juliana L.; Paredes-Gamero, Edgar J.; Souza, Ana C. S.; Tersariol, Ivarne L. S.; Santos, Elizeu A.; Nader, Helena B.; Justo, Giselle Z.; Sales, Maurício P. dePurpose In this study, the antitumoral potential of a novel lectin (CvL) puriWed from the marine sponge Cliona varians was studied in diVerent cancer cell lines. Methods CvL cytotoxicity was evaluated in mammalian tumor cells and in normal human peripheral blood lymphocytes by the MTT assay using the same range of concentrations (1–150 _g ml¡1). The mechanisms involved in K562 cell death were investigated by confocal Xuorescence microscopy, Xow cytometry and immunoblot. Results CvL inhibited the growth of human leukemia cells, with IC50 values of 70 and 100 _gml¡1 for K562 and JURKAT cells, respectively, but it was ineVective on blood lymphocytes and solid tumor cell lines. K562 cell death occurred 72 h after exposure to the lectin and with signs of apoptosis, as analyzed by DAPI and annexin V/PI staining. Investigation of the possible mediators of this process showed that cell death occurred via a caspase-independent pathway. Confocal Xuorescence microscopy indicated a pivotal role for the lysosomal protease cathepsin B in mediating cell death. Accordingly, pre-incubation of K562 cells with the cathepsin inhibitor L-trans-epoxysuccinyl-L-leucylamido-(4-guanidino)butane (E-64) abolished CvL cytotoxic eVect. Furthermore, we found upregulation of tumor necrosis factor receptor 1 (TNFR1) and down-modulation of p65 subunit of nuclear factor kappa B (NF_B) expression in CvL-treated cells. These eVects were accompanied by increased levels of p21 and reduced expression of pRb, suggesting that CvL can induce cell cycle arrest. Conclusions Collectively, these Wndings indicate an antileukemic eVect for CvL and suggest that cathepsin B acts as a death mediator in CvL-induced cytotoxicity possibly in an uncharacterized connection with the membrane death receptor pathway.Artigo Pro-inflammatory effect in mice of CvL, a lectin from the marine sponge Cliona varians(Elsevier, 2007) Queiroz, Alexandre F.S.; Moura, Raniere M.; Ribeiro, Jannison K.C.; Lyra, Ibson L.; Cunha, Dayse C.S.; Santos, Elizeu A.; de-Sales, Maurício. P.CvL, a lectin from the marine sponge Cliona varians agglutinated type A papainized erythrocytes and was strongly inhibited by D-galactose and sucrose. Models of leukocyte migration in vivo were used to study the inflammatory activity of CvL through of mouse paw oedema and peritonitis. Effect of CvL on peritoneal macrophage activation was analysed. Effects of corticoids and NSAIDS drugs were also evaluated on peritonitis stimulated by CvL. Results showed that mouse hind-paw oedema induced by subplantar injections of CvL was dose dependent until 50 μg/cavity. This CvL dose when administered into mouse peritoneal cavities induced maxima cell migration (9283 cells/μL) at 24 h after injection. This effect was preferentially inhibited by incubation of CvL with the carbohydrates D-galactose followed by sucrose. Pre-treatment of mice with 3% thioglycolate increases the peritoneal macrophage population 2.3 times, and enhanced the neutrophil migration after 24 h CvL injection (75.8%, pb0.001) and no significant effect was observed in the presence of fMLP. Finally, pre-treatment of mice with dexamethasone (cytokine antagonist) decreased (65.6%, pb0.001), diclofenac (non-selective NSAID) decreased (34.5%, pb0.001) and Celecoxib (selective NSAID) had no effect on leukocyte migration after submission at peritonitis stimulated by CvL, respectively. Summarizing, data suggest that CvL shows pro-inflammatory activity, inducing neutrophil migration probably by pathway on resident macrophage activation and on chemotaxis mediated by cytokines.