RESUMO
The antiproliferative and cytotoxic activity of glucolaxogenin and its ability to induce apoptosis and autophagy in cervical cancer cells are reported. We ascertained that glucolaxogenin exerts an inhibitory effect on the proliferation of HeLa, CaSki and ViBo cells in a dose-dependent manner. Analysis of DNA distribution in the cell-cycle phase of tumor cells treated with glucolaxogenin suggests that the anti-proliferative activity of this steroid is not always dependent on the cell cycle. Cytotoxic activity was evaluated by detection of the lactate dehydrogenase enzyme in supernatants from tumor cell cultures treated with the steroid. Glucolaxogenin exhibited null cytotoxic activity. With respect to the apoptotic activity, the generation of apoptotic bodies, the presence of active caspase-3 and annexin-V, as well as the DNA fragmentation observed in all tumor lines after treatment with glucolaxogenin suggests that this compound does indeed induce cell death by apoptosis. Also, a significantly increased presence of the LC3-II, LC3 and Lamp-1 proteins was evidenced with the ultrastructural existence of autophagic vacuoles in cells treated with this steroidal glycoside, indicating that glucolaxogenin also induces autophagic cell death. It is important to note that this compound showed no cytotoxic effect and did not affect the proliferative capacity of mononuclear cells obtained from normal human peripheral blood activated by phytohaemagglutinin. Thus, glucolaxogenin is a compound with anti-proliferative properties that induces programmed cell death in cancer cell lines, though it is selective with respect to normal lymphocytic cells. These findings indicate that this glycoside could have a selective action on tumor cells and, therefore, be worthy of consideration as a therapeutic candidate with anti-tumor potential.
Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Neoplasias do Colo do Útero/tratamento farmacológico , Anexina A5/metabolismo , Caspase 3/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Feminino , Glicosídeos/metabolismo , Células HeLa , Humanos , L-Lactato Desidrogenase/metabolismo , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Fito-Hemaglutininas/metabolismo , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologiaRESUMO
Acacia farnesiana lectin-like protein (AFAL) is a chitin-binding protein and has been classified as phytohaemagglutinin from Phaseolus vulgaris (PHA). Legume lectins are examples for structural studies, and this family of proteins shows a remarkable conservation in primary, secondary, and tertiary structures. Lectins have ability to reduce the effects of inflammation caused by phlogistic agents, such as carrageenan (CGN). This paper explains the anti-inflammatory activity of AFAL through structural comparison with anti-inflammatory legume lectins. The AFAL model was obtained by molecular modeling and molecular docking with glycan and carrageenan were performed to explain the AFAL structural behavior and biological activity. Pisum sativum lectin was the best template for molecular modeling. The AFAL structure model is folded as a ß sandwich. The model differs from template in loop regions, number of ß strands and carbohydrate-binding site. Carrageenan and glycan bind to different sites on AFAL. The ability of AFAL binding to carrageenan can be explained by absence of the sixth ß -strand (posterior ß sheets) and two ß strands in frontal region. AFAL can inhibit pathway inflammatory process by carrageenan injection by connecting to it and preventing its entry into the cell and triggers the reaction.
Assuntos
Anti-Inflamatórios/química , Inflamação/tratamento farmacológico , Modelos Moleculares , Lectinas de Plantas/química , Acacia , Animais , Anti-Inflamatórios/metabolismo , Carragenina/toxicidade , Quitina/química , Cristalografia por Raios X , Inflamação/induzido quimicamente , Inflamação/patologia , Camundongos , Simulação de Acoplamento Molecular , Fito-Hemaglutininas/química , Fito-Hemaglutininas/metabolismo , Lectinas de Plantas/administração & dosagem , Lectinas de Plantas/isolamento & purificação , Lectinas de Plantas/metabolismo , Ligação ProteicaRESUMO
The mesopontine rostromedial tegmental nucleus (RMTg) is a mostly γ-aminobutyric acid (GABA)ergic structure believed to be a node for signaling aversive events to dopamine (DA) neurons in the ventral tegmental area (VTA). The RMTg receives glutamatergic inputs from the lateral habenula (LHb) and sends substantial GABAergic projections to the VTA, which also receives direct projections from the LHb. To further specify the topography of LHb projections to the RMTg and VTA, small focal injections of the anterograde tracer Phaseolus vulgaris leucoagglutinin were aimed at different subdivisions of the LHb. The subnuclear origin of LHb inputs to the VTA and RMTg was then confirmed by injections of the retrograde tracer cholera toxin subunit b into the VTA or RMTg. Furthermore, we compared the topographic position of retrogradely labeled neurons in the RMTg resulting from VTA injections with that of anterogradely labeled axons emerging from the LHb. As revealed by anterograde and retrograde tracing, LHb projections were organized in a strikingly topographic manner, with inputs to the RMTg mostly arising from the lateral division of the LHb (LHbL), whereas inputs to the VTA mainly emerged from the medial division of the LHb (LHbM). In the RMTg, profusely branched LHb axons were found in close register with VTA projecting neurons and were frequently apposed to the latter. Overall, our findings demonstrate that LHb inputs to the RMTg and VTA arise from different divisions of the LHb and provide direct evidence for a disynaptic pathway that links the LHbL to the VTA via the RMTg.
Assuntos
Habenula/citologia , Tegmento Mesencefálico/citologia , Área Tegmentar Ventral/citologia , Animais , Toxina da Cólera/metabolismo , Habenula/fisiologia , Masculino , Vias Neurais/citologia , Vias Neurais/fisiologia , Fito-Hemaglutininas/metabolismo , Ratos , Ratos Wistar , Tegmento Mesencefálico/fisiologia , Área Tegmentar Ventral/fisiologiaRESUMO
The parasubthalamic nucleus (PSTN) is a differentiation of the lateral hypothalamic area, characterized by a distinct population of neurons expressing beta-preprotachykinin (beta-PPT) mRNA. The axonal projections from the PSTN have been analyzed with the PHAL anterograde tract tracing method in rats. The results indicate that the cell group is distinguished by massive projections to parasympathetic preganglionic neurons in the brainstem (especially in the salivatory nuclei and dorsal motor nucleus of the vagus nerve) and to parts of the parabrachial nucleus and nucleus of the solitary tract that relay viscerosensory and gustatory information. In addition, the PSTN projects to cortical parts of the cerebral hemisphere (infralimbic, agranular insular, postpiriform transition and lateral entorhinal areas, and posterior basolateral amygdalar nucleus)-directly and also indirectly via thalamic feedback loops involving the paraventricular and mediodorsal nuclei-and to nuclear parts of the cerebral hemisphere (central amygdalar nucleus, striatal fundus, rhomboid nucleus of the bed nuclei of the stria terminalis, and substantia innominata). The PSTN is thus positioned to influence directly many cerebral hemisphere and hindbrain components of the central parasympathetic control network that is active, for example, during feeding behavior and cardiovascular regulation.
Assuntos
Axônios/fisiologia , Vias Neurais/fisiologia , Núcleo Subtalâmico/citologia , Animais , Hibridização In Situ/métodos , Masculino , Vias Neurais/metabolismo , Fito-Hemaglutininas/metabolismo , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Ratos , Ratos Sprague-Dawley , Coloração e Rotulagem , Núcleo Subtalâmico/metabolismo , Taquicininas/genética , Taquicininas/metabolismoRESUMO
EJ-ras oncogene-induced malignant transformation is characterized by a series of changes in cell surface carbohydrates and cell-cell and cell-matrix interactions. Here, we show that EJ-ras-transformed NIH-3T3 fibroblasts acquired a migratory phenotype on laminin-1 surfaces. Such a phenotype was accompanied by overexpression of: (a) functional alpha6beta1, but not other laminin binding beta1-integrins; and (b) glycoconjugates on the cell surface bearing large oligosaccharides recognized by leukoagglutinin from Phaseolus vulgaris (L-PHA). The internal pool of pre-beta1-integrins was differently regulated in EJ-ras-transformed cells compared with nontransfected fibroblasts. Conversion of pre-beta1- into mature beta1-integrins was faster in EJ-ras-transformed cells, a process associated with the overexpression of the alpha6-chain. Overexpression of L-PHA-reactive oligosaccharides is dependent on the activity of N-acetylglucosaminyltransferase V, which is increased in transformed cells [J. W. Dennis et al., Science (Washington DC), 236: 582-585, 1987]. We show that beta1-integrins were the major carriers of L-PHA-reactive oligosaccharides on the cell surface. This glycosylation pattern, however, was not necessary for either the cell surface expression of beta1-integrins or their functional activity in the migratory response to laminin-1. Moreover, EJ-ras-transformed fibroblasts aggregated spontaneously. These effects were not observed in c-jun-transfected fibroblasts, which were unable to migrate on laminin, did not overexpress either beta1-integrins or L-PHA-reactive oligosaccharides, and did not self-aggregate.
Assuntos
Genes ras , Integrina beta1/metabolismo , Integrinas/fisiologia , Laminina/fisiologia , Oligossacarídeos/metabolismo , Células 3T3 , Animais , Linhagem Celular Transformada , Movimento Celular , Transformação Celular Neoplásica/metabolismo , Feminino , Glicosilação , Integrina alfa6beta1 , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Fito-Hemaglutininas/metabolismoRESUMO
The present research consisted of an evaluation of five genotypes harvested from six growing locations. Variables of sensory properties, cooking quality and nutritional characteristics were determined. Genotype with longer cooking time was BV which also present hard shell. Those of shorter cooking time were FMB and PV. In Calera frosting during pod filling, drastically reduced cooking time, sensory properties and tannins. Taking this location off, the analysis show little effect of genotype or growing location in regard to determined properties. The genotypes with lower content of tannins were PV and BV. The content of lectins were in general low for all samples and the diferences between genotypes were not statistically significant (p<0.05) but they did for growing location.
Assuntos
Fabaceae/metabolismo , Valor Nutritivo , Plantas Medicinais , Limiar Gustativo , Análise de Variância , Fabaceae/genética , Manipulação de Alimentos , Genótipo , Temperatura Alta , Humanos , Fito-Hemaglutininas/metabolismo , Lectinas de Plantas , Solo/análise , Fatores de TempoRESUMO
The ability of lectins to interact with Yersinia pestis strains isolated from rodent fleas and human biological fluids, obtained from different geographic areas, was examined. Lectins of Canavalia ensiformis, Ulex europaeus, Phaseolus vulgaris, and Triticum vulgaris, as well as a new autochthonous lectin of Swartzia pickellii of undefined specificity, were used. Most of the Y. pestis strains did not agglutinate with U. europaeus or C. ensiformis lectin. However, P. vulgaris lectin agglutinated suspensions of all the bacillus strains used. Fifteen of the 19 strains tested positive for assays using S. pickellii lectin. It is believed this is the first report of Y. pestis strain agglutination by lectins. A similar agglutination pattern was obtained for lectins with specificity for oligosaccharides containing N-acetylglucosamine and S. pickellii lectin, which did bind to the affinity matrix chitin, a polysaccharide of N-acetylglucosamine. The use of bacterial strains and commercial lectins of defined specificity may be an approach to providing evidence about the lectin binding sites of undefined monosaccharide specificity.
Assuntos
Lectinas/metabolismo , Lectinas de Plantas , Yersinia pestis/metabolismo , Aglutinação , Sequência de Carboidratos , Concanavalina A/metabolismo , Dados de Sequência Molecular , Fito-Hemaglutininas/metabolismo , Aglutininas do Germe de Trigo/metabolismo , Yersinia pestis/classificaçãoRESUMO
El método de rosetas con eritrocitos de pollo recubiertos de IgG se ha utilizado junto con separación por flotación en ficoll-hypaque para obtener subpoblaciones de células enriquecidas o disminuidas de linfocitos T con receptor para Fc de IgG (Tg). Estas poblaciones celulars se han utilizado para determinar producción de LIF a diferentes concentraciones de los mitógenos, utilizando un método en microgota de agarosa. De esta manera, hemos podido observar una respuesta semejante en las diferentes poblaciones celulares hacia concanavalina A y una respuesta diferencial hacia fitohemaglitinina donde por lo general se observa una respuesta negativa de la población enriquecida con células Tg mientras que las poblaciones de linfocitos totales o aquellas en las que se han eliminado las Tg dan una respuesta positiva al segundo mitógeno