RESUMEN
Propolis, a resinous substance collected by honeybees by mixing their saliva with plant sources, including tree bark and leaves and then mixed with secreted beeswax, possesses a variety of bioactivities. Whereas caffeic acid phenethyl ester (CAPE) has been recognized as a major bioactive ingredient in New Zealand propolis, Brazilian green propolis, on the other hand, possesses artepillin C (ARC). In this study, we report that, similar to CAPE, ARC docks into and abrogates mortalin-p53 complexes, causing the activation of p53 and the growth arrest of cancer cells. Cell viability assays using ARC and green propolis-supercritical extract (GPSE) revealed higher cytotoxicity in the latter, supported by nuclear translocation and the activation of p53. Furthermore, in vivo tumor suppression assays using nude mice, we found that GPSE and its conjugate with γ cyclodextrin (γCD) possessed more potent anticancer activity than purified ARC. GPSEγCD may thus be recommended as a natural, effective and economic anticancer amalgam.
Asunto(s)
Antineoplásicos/farmacología , Supervivencia Celular/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Fenilpropionatos/farmacología , Própolis/farmacología , Animales , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Brasil , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Cromatografía con Fluido Supercrítico , Biología Computacional , Femenino , Proteínas HSP70 de Choque Térmico/metabolismo , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Proteínas Mitocondriales/metabolismo , Simulación del Acoplamiento Molecular , Fenilpropionatos/química , Fenilpropionatos/uso terapéutico , Própolis/química , Própolis/uso terapéutico , Proteína p53 Supresora de Tumor/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto , gamma-Ciclodextrinas/química , gamma-Ciclodextrinas/farmacología , gamma-Ciclodextrinas/uso terapéuticoRESUMEN
Azulenequinone derivatives have been reported to display a broad spectrum of biological activities, but study at the cellular level has been limited. The effect of twenty-seven azulenequinone derivatives on nitric oxide (NO) production by mouse macrophage-like cells Raw 264.7 was investigated in this study. All of these compounds failed to stimulate the Raw 264.7 cells to produce detectable amounts of NO, but did inhibit NO production by lipopolysaccharide (LPS)-activated Raw 264. 7 cells to varying extents. Compounds [7, 8, 9, 13, 16, 25, 27], which showed lesser cytotoxic activity (CC50 = 425, 381, 482, 179, 119, 235, 225 microM, respectively), inhibited NO production to the greatest extent [selectivity index (SI) = 15.4, 26.2, 3.9, 21.6, 3.1, 6.0, 8.4, respectively]. Western blot and RT-PCR analyses demonstrated that the most active derivatives, 3-morpholino-1, 5-azulenequinone [8] and 3,7-dibromo-1, 5-azulenequinone [13], significantly reduced both the intracellular concentration of iNOS protein and the expression of iNOS mRNA. ESR spectroscopy showed that compounds [8, 13] weakly scavenged NO produced by NOC-7, possibly via their general reducing activity. These data suggest that the inhibitory effect of NO production by compounds [8, 13] might be generated mostly via the inhibition of iNOS expression, rather than the radical-mediated mechanism.
Asunto(s)
Azulenos/farmacología , Lipopolisacáridos/antagonistas & inhibidores , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico/biosíntesis , Quinonas/farmacología , Animales , Benzoatos/metabolismo , Benzoatos/farmacología , Western Blotting , Línea Celular , Óxidos N-Cíclicos/metabolismo , Óxidos N-Cíclicos/farmacología , Espectroscopía de Resonancia por Spin del Electrón , Depuradores de Radicales Libres/farmacología , Hidrazinas/metabolismo , Hidrazinas/farmacología , Hipoxantina/metabolismo , Imidazoles/metabolismo , Imidazoles/farmacología , Lipopolisacáridos/farmacología , Macrófagos/enzimología , Ratones , Donantes de Óxido Nítrico/metabolismo , Donantes de Óxido Nítrico/farmacología , Óxido Nítrico Sintasa de Tipo II/biosíntesis , Óxido Nítrico Sintasa de Tipo II/genética , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Superóxidos/metabolismo , Xantina Oxidasa/metabolismoRESUMEN
Intraperitoneal administration of fermented pine seed shell extract (PSSE) (up to 2 g/kg) induced no apparent acute toxicity to mice. Pretreatment of mice with PSSE protected them from the lethality of Escherichia coli infection. PSSE showed a very weak cytotoxic activity against both normal and tumor cells and no anti-HIV activity, but stimulated the mouse macrophage-like Raw 264.7 cells to produce nitric oxide (NO) and citrulline. ESR spectroscopy showed that PSSE produced no detectable radicals, but effectively scavenged O2- (generated by the hypoxanthine-xanthine oxidase reaction), hydroxyl radical (generated by the Fenton reaction) and NO (generated by NOC-7). Comparison of PSSE with other natural products, such as polyphenols and vitamins, further confirmed the close association between radical intensity and radical scavenging activity, suggesting the bimodal action of natural products. Although the biological activities of PSSE were relatively lower than those of other natural products, the present study suggests the possible medicinal efficacy of PSSE.