RESUMEN
Alcoholic extract of Piper betle (Piper betle L.) leaves was recently found to induce apoptosis of CML cells expressing wild type and mutated Bcr-Abl with imatinib resistance phenotype. Hydroxy-chavicol (HCH), a constituent of the alcoholic extract of Piper betle leaves, was evaluated for anti-CML activity. Here, we report that HCH and its analogues induce killing of primary cells in CML patients and leukemic cell lines expressing wild type and mutated Bcr-Abl, including the T315I mutation, with minimal toxicity to normal human peripheral blood mononuclear cells. HCH causes early but transient increase of mitochondria-derived reactive oxygen species. Reactive oxygen species-dependent persistent activation of JNK leads to an increase in endothelial nitric oxide synthase-mediated nitric oxide generation. This causes loss of mitochondrial membrane potential, release of cytochrome c from mitochondria, cleavage of caspase 9, 3 and poly-adenosine diphosphate-ribose polymerase leading to apoptosis. One HCH analogue was also effective in vivo in SCID mice against grafts expressing the T315I mutation, although to a lesser extent than grafts expressing wild type Bcr-Abl, without showing significant bodyweight loss. Our data describe the role of JNK-dependent endothelial nitric oxide synthase-mediated nitric oxide for anti-CML activity of HCH and this molecule merits further testing in pre-clinical and clinical settings.
Asunto(s)
Apoptosis/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Eugenol/análogos & derivados , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , MAP Quinasa Quinasa 4/metabolismo , Mitocondrias/efectos de los fármacos , Óxido Nítrico Sintasa de Tipo III/metabolismo , Piper betle/química , Especies Reactivas de Oxígeno/metabolismo , Animales , Antineoplásicos/farmacología , Benzamidas , Western Blotting , Eugenol/química , Eugenol/farmacología , Citometría de Flujo , Proteínas de Fusión bcr-abl/genética , Humanos , Mesilato de Imatinib , Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Masculino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Ratones Desnudos , Ratones SCID , Mitocondrias/metabolismo , Óxido Nítrico/metabolismo , Fosforilación/efectos de los fármacos , Piperazinas/farmacología , Extractos Vegetales/farmacología , Hojas de la Planta/química , Pirimidinas/farmacología , Células Tumorales CultivadasRESUMEN
Themisone, also known as Atrolactamide, was found, in the 1950s, to be a very potent anticonvulsant. It was hypothesized that the -CF(3) substitution would maintain the anticonvulsant activity. Anticonvulsant testing of our novel compounds by the National Institute of Health's Anticonvulsant Screening Project of the Antiepileptic Drug Discovery Program identified analogue 1, 3,3,3-trifluoro-2-hydroxy-2-phenyl-propionamide, to have potent anticonvulsant activity (MES ED(50) of 9.9 mg/kg, ScMET ED(50) of 34 mg/kg and TD(50) of 100 mg/kg). Therefore, a diverse range of analogues were synthesized utilizing multiple synthetic pathways to explore the structure-activity relationship. Patch clamp electrophysiology experiments demonstrate that compound 1 is an effective T-type calcium channel blocker. Altogether, these results suggest these compounds as a class of orally available anticonvulsants.
Asunto(s)
Anticonvulsivantes/síntesis química , Hidroxiácidos/síntesis química , Hidroxiácidos/farmacocinética , Administración Oral , Amidas/síntesis química , Amidas/farmacocinética , Animales , Anticonvulsivantes/farmacocinética , Disponibilidad Biológica , Bloqueadores de los Canales de Calcio/síntesis química , Bloqueadores de los Canales de Calcio/farmacocinética , Células Cultivadas , Relación Dosis-Respuesta a Droga , Diseño de Fármacos , Neuronas/efectos de los fármacos , Técnicas de Placa-Clamp , Ratas , Convulsiones/tratamiento farmacológico , Convulsiones/prevención & control , Relación Estructura-ActividadRESUMEN
The trisaccharide, 3-aminopropyl 5-acetamido-3,5-dideoxy-D-glycero-alpha-D-galacto-2-nonulopyranosylonic acid-(2-->3)-beta-D-galactopyranosyl-(1-->4)-2-acetamido-2-deoxy-beta-D-glucopyranoside has been synthesized chemoenzymatically for the first time. First, the acceptor, 3-aminopropyl beta-D-galactopyranosyl-(1-->4)-2-acetamido-2-deoxy-beta-D-glucopyranoside was synthesized in a conventional chemical manner, and then it was coupled with CMP-sialic acid using alpha-(2-->3)-(N)-sialyltransferase to afford the desired trisaccharide by an enzymatically stereocontrolled manner.
Asunto(s)
Glucósidos/síntesis química , Oligosacáridos/síntesis química , Trisacáridos/síntesis química , Conformación de Carbohidratos , Secuencia de Carbohidratos , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Glucósidos/química , Glicosilación , Datos de Secuencia Molecular , Oligosacáridos/química , Sialiltransferasas/química , Sialiltransferasas/metabolismo , Trisacáridos/químicaRESUMEN
We have recently discovered a novel class of compounds that have oral general anesthetic activity, potent anticonvulsant activity, and minimal hemodynamic effects. The 3,3,3-trifluoro-2-hydroxy-2-phenyl-propionamide (1) demonstrated potent ability to reduce the minimum alveolar concentration (MAC) of isoflurane, with no effects on heart rate or blood pressure at therapeutic concentrations. Analogue 1 also had potent oral anticonvulsant activity against maximal electroshock (MES) and subcutaneous metrazol (scMET) models with a therapeutic index of 10 for MES activity. In this study, we further synthesized nine new racemic analogues and evaluated these compounds for effects on isoflurane MAC reduction and blood pressure. Preliminary data demonstrate potent reduction in the isoflurane MAC for two new compounds. Current mechanistic studies were unrevealing for effects on voltage-gated ion channels as a putative mechanism. Liposomal partitioning studies using (19)F NMR reveal that the aromatic region partitions into the core of the lipid. This partitioning correlated with general anesthetic activity of this class of compounds. Further, compound 1 was used at a concentration of 1 mM and slightly enhanced GABA(A) current in hippocampal neurons at 10 microM. Altogether, 3,3,3-trifluoro-2-hydroxy-2-phenyl-propionamide exhibited excellent oral general anesthetic activity and appears devoid of significant side effects (i.e., alterations in blood pressure or heart rate).
Asunto(s)
Amidas/síntesis química , Anestésicos Generales/síntesis química , Propionatos/síntesis química , Administración Oral , Amidas/química , Amidas/farmacología , Anestésicos Generales/química , Anestésicos Generales/farmacología , Animales , Anticonvulsivantes/síntesis química , Anticonvulsivantes/química , Anticonvulsivantes/farmacología , Presión Sanguínea/efectos de los fármacos , Células Cultivadas , Diseño de Fármacos , Frecuencia Cardíaca/efectos de los fármacos , Hipocampo/citología , Hipocampo/fisiología , Técnicas In Vitro , Activación del Canal Iónico , Canales Iónicos/efectos de los fármacos , Canales Iónicos/fisiología , Isoflurano/análisis , Liposomas/química , Espectroscopía de Resonancia Magnética , Masculino , Ratones , Propionatos/química , Propionatos/farmacología , Alveolos Pulmonares/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Receptores de GABA-A/efectos de los fármacos , Receptores de GABA-A/fisiología , Estereoisomerismo , Relación Estructura-Actividad , XenopusRESUMEN
The early detection and treatment of prostate cancer have increased survival and improved clinical outcomes. The nature of the disease and pathologic understaging result in a high proportion of patients developing locally recurrent disease or distant metastases. The development of prostate cancer the time from tumor initiation and progression to invasive carcinoma often begins in men in the fourth or fifth decades of life and extends across decades. This prolonged window highlights the tremendous clinical impact that early intervention with therapeutic agents that selectively target the invasive and metastatic potential of the prostate cancer cell could have on patient survival and quality of life. Our research is currently focused on the development and testing of novel voltage-gated ion channel blockers. The expression of voltage-gated sodium channels (VGSCs) was recently associated with the metastatic behavior of prostate cancer cells. In these studies, VGSC blockers altered prostate cancer cell morphology and arrested prostate cancer cell migration. Clinically, one of the most widely used sodium channel blockers is phenytoin. We have used rational drug design based on the phenytoin binding site in a VGSC to make novel sodium channel blockers with enhanced activity and minimal acute toxicity. Our initial studies in vitro demonstrate enhanced binding of the compounds to the sodium channel and increased inhibition of prostate cancer cell growth in culture and in soft agarose compared with phenytoin. These derivatives are currently being tested for their antitumor activity in human prostate cancer xenografts.