RESUMEN
Two new compounds, pycnanthuquinone A (1) and pycnanthuquinone B (2), were isolated from leaves and stems of the African plant, Pycnanthus angolensis (Welw.) Warb (Myristicaceae), by bioassay-guided fractionation of an ethanolic extract using a diabetic mouse model. Pycnanthuquinones A and B are the first representatives of a novel terpenoid-type quinone skeleton, and both compounds possess significant antihyperglycemic activity.
Asunto(s)
Ácidos Grasos Insaturados/aislamiento & purificación , Hipoglucemiantes/aislamiento & purificación , Naftoquinonas/aislamiento & purificación , Plantas Medicinales/química , África , Animales , Glucemia/metabolismo , Peso Corporal/efectos de los fármacos , Diabetes Mellitus/sangre , Diabetes Mellitus/genética , Ingestión de Alimentos/efectos de los fármacos , Ácidos Grasos Insaturados/farmacología , Hipoglucemiantes/farmacología , Espectroscopía de Resonancia Magnética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Obesos , Naftoquinonas/farmacología , Extractos Vegetales/química , Hojas de la Planta/química , Tallos de la Planta/químicaRESUMEN
Utilizing the co-transfection assay as a guide to determining structure activity relationships, we have been pursuing the discovery of non-steroidal hPR modulators. Small molecule, non-steroidal lead structures have been identified. Optimization of these structures has yielded more potent hPR modulators. Improved cross-reactivity profiles with other intracellular receptors are a feature of these compounds owing to their non-steroidal nature.
Asunto(s)
Diseño de Fármacos , Antagonistas de Hormonas/química , Congéneres de la Progesterona/efectos adversos , Receptores de Progesterona/efectos de los fármacos , Animales , Anisoles/química , Anisoles/farmacocinética , Chlorocebus aethiops , Chlorophyta/química , Ciclohexanos/química , Ciclohexanos/farmacocinética , Terapia de Reemplazo de Estrógeno , Femenino , Gonanos/química , Gonanos/farmacocinética , Antagonistas de Hormonas/farmacocinética , Humanos , Mifepristona/química , Mifepristona/farmacocinética , Estructura Molecular , Congéneres de la Progesterona/farmacocinética , Receptores de GABA/efectos de los fármacos , Receptores de GABA/fisiología , Receptores de Progesterona/metabolismo , Receptores de Esteroides/efectos de los fármacos , Receptores de Esteroides/metabolismo , Proteínas Recombinantes/efectos de los fármacos , Fases del Sueño/efectos de los fármacos , Relación Estructura-Actividad , TransfecciónRESUMEN
The co-transfection assay is a novel functional assay using cells transiently transfected with plasmids encoding intracellular receptors and corresponding reporter genes. Using this assay, natural product extracts were tested to identify compounds that modulate intracellular receptor activity, measured as changes in reporter gene activity. A crude extract of the marine alga Cymopolia barbata was found to inhibit progesterone-stimulated reporter gene expression in cells transfected with the human progesterone receptor (hPR) and an appropriate reporter construct. Purification of the active constituents of the extract, guided by the co-transfection assay, yielded two diastereomers of cyclocymopol monomethyl ether, possessing opposing pharmacological activities with the hPR. The antagonist (3R)-cyclocymopol monomethyl ether (LG100127) blocked 1 nM progesterone-stimulated reporter gene expression with an IC50 value of 549 +/- 55 nM in the co-transfection assay. The agonist (3S)-cyclocymopol monomethyl ether (LG100128) had efficacy similar to that of progesterone and an EC50 value of 35 +/- 2 nM. Stimulation by progesterone of the hPR in the human breast cancer cell line T-47D results in enhanced expression of alkaline phosphatase; LG100127 blocked alkaline phosphatase expression stimulated either by progesterone or by LG100128, and LG100128 mimicked progesterone in this assay. Both diastereomers displaced [3H]progesterone from baculovirus-expressed hPR. LG100127 and LG100128 each interacted with the human androgen receptor but did not interact with the human glucocorticoid receptor, estrogen receptor, vitamin D receptor, or retinoid receptors. In summary, these in vitro studies describe the first nonsteroidal pharmacophores for the hPR and demonstrate the use of the co-transfection assay in their discovery.