RESUMEN
Inhibition of p38 kinase blocks the production of tumor-promoting factors in the multiple myeloma (MM) bone marrow microenvironment. Proteasome inhibitors MG132 and bortezomib have been shown to have direct cytotoxic effects on MM cells. We show that a selective inhibitor of p38alpha, SCIO-469, enhances the ability of MG132 and bortezomib to induce the apoptosis of MM cells. Previously, we showed that p38 inhibition with SCIO-469 enhances MM cytotoxicity of bortezomib by inhibiting the transient expression and phosphorylation of Hsp27, a downstream target of p38. Here we show that continued treatment of MM cells with bortezomib leads to a SCIO-469-enhanced downregulation of Hsp27 and to increased MM apoptosis. Furthermore, we show that p38 inhibition enhances the bortezomib-induced MM apoptosis by upregulation of p53 and downregulation of Bcl-X(L) and Mcl-1. In a mouse xenograft plasmacytoma model of MM, we found that inhibiting p38 augments the effects of bortezomib in decreasing MM tumor growth in vivo. Thus, in addition to its role in suppressing an activated MM microenvironment, co-treatment with a p38 inhibitor, such as SCIO-469, may enhance the cytotoxicity of bortezomib by modulating pro-apoptotic and anti-apoptotic factors in MM cells, suggesting great potential for co-therapy.
Asunto(s)
Proteínas de Choque Térmico/metabolismo , Indoles/farmacología , Proteína Quinasa 14 Activada por Mitógenos/antagonistas & inhibidores , Mieloma Múltiple/metabolismo , Proteínas de Neoplasias/metabolismo , Inhibidores de Proteasas/farmacología , Proteína p53 Supresora de Tumor/metabolismo , Proteína bcl-X/metabolismo , Administración Oral , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Apoptosis/efectos de los fármacos , Ácidos Borónicos/administración & dosificación , Ácidos Borónicos/farmacología , Bortezomib , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Regulación hacia Abajo , Activación Enzimática/efectos de los fármacos , Proteínas de Choque Térmico HSP27 , Proteínas de Choque Térmico/efectos de los fármacos , Humanos , Técnicas In Vitro , Indoles/administración & dosificación , Inyecciones Intravenosas , Leupeptinas/farmacología , Ratones , Ratones Desnudos , Proteína Quinasa 14 Activada por Mitógenos/metabolismo , Chaperonas Moleculares , Mieloma Múltiple/enzimología , Proteínas de Neoplasias/efectos de los fármacos , Inhibidores de Proteasas/administración & dosificación , Pirazinas/administración & dosificación , Pirazinas/farmacología , Células Tumorales Cultivadas , Proteína p53 Supresora de Tumor/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto , Proteína bcl-X/efectos de los fármacosRESUMEN
This study investigates the antinociceptive and the oedema inhibition properties of the novel non-peptide bradykinin (BK) B2 receptor antagonist, NPC 18884. Given by i.p. or p.o. routes NPC 18884 produced graded and long-lasting (at least 2.5h and 5.0h, respectively, for i.p. and p.o. administration) inhibition of acetic acid-induced abdominal constrictions in mice, with mean ID50 values of 8.3 nmol/kg and 439.9 nmol/kg. NPC 18884 also inhibited kaolin-induced abdominal constrictions (44+/-9% and 48+/-3% of inhibition, for i.p. and p.o. routes, respectively). Given by i.p. or p.o. routes NPC 18884 attenuated both phases of formalin-induced licking, as well as formalin-induced oedema formation. At similar doses NPC 18884 produced significant inhibition of capsaicin-induced nociception. NPC 18884, like HOE 140 given i.p., prevented the nociception caused by BK with mean ID50 values of 0.85 nmol/kg and 0.44 nmol/kg, respectively. Given orally NPC 18884, but not HOE 140, caused graded inhibition of BK-induced nociception (mean ID50 value of 50 nmol/kg). In rats, NPC 18884 given i.p. prevented BK and carrageenan-induced hyperalgesia (mean ID50 values of 6 nmol/kg and 13 nmol/kg), without affecting the hyperalgesia induced by des-Arg9-bradykinin (DABK) or by prostaglandin E2 (PGE2). NPC 18884 given i.p. inhibited the mouse paw oedema induced by tyrosine8-bradykinin or by carrageenan, but had no effect on DABK-induced oedema in mice pre-treated with Escherichia coli endotoxin, or that induced by PGE2. Thus, the novel non-peptide BK B2 receptor antagonist NPC 18884 produces rapid onset, potent and relatively long-lasting oral antinociceptive and oedema inhibition properties. The anti-BK actions of NPC 18884 are quite selective towards the BK B2 receptor-mediated responses.
Asunto(s)
Analgésicos/farmacología , Antagonistas de los Receptores de Bradiquinina , Dipéptidos/farmacología , Edema/prevención & control , Dolor/prevención & control , Ácido Acético/efectos adversos , Administración Oral , Animales , Conducta Animal/efectos de los fármacos , Bradiquinina/efectos adversos , Bradiquinina/análogos & derivados , Capsaicina/efectos adversos , Carragenina/efectos adversos , Dinoprostona/efectos adversos , Relación Dosis-Respuesta a Droga , Edema/inducido químicamente , Formaldehído/efectos adversos , Miembro Posterior , Hiperalgesia/inducido químicamente , Hiperalgesia/prevención & control , Inyecciones Intraperitoneales , Masculino , Ratones , Dolor/inducido químicamente , Ratas , Ratas Wistar , Receptor de Bradiquinina B2 , Factores de TiempoRESUMEN
In an effort to rapidly identify potent inhibitors of Abeta production and to probe the amino acid sequence specificity of the protease(s) responsible for the production of this peptide, a large number of dipeptide aldehydes were combinatorially synthesized and manually evaluated for their inhibitory properties. The starting point for this study was the dipeptide aldehyde carbobenzoxyl-valinyl-phenylalanal previously shown to inhibit the production of Abeta in CHO cells stably transfected with the cDNA encoding betaAPP695. Pools of related dipeptide aldehydes were combinatorially synthesized, and the most active pool was deconvoluted, resulting in the identification of the most active inhibitor of this pool. Systematic optimization of this inhibitor resulted in a series of dipeptide aldehydes with enhanced potencies relative to carbobenzoxyl-valinyl-phenylalanal. The most active dipeptide aldehydes were those that possessed hydrophobic amino acids at both the P1 and P2 positions. The most potent compound identified in this study was 3, 5-dimethoxycinnamamide-isoleucinyl-leucinal with an IC(50) of 9.6 microM, approximately 10-fold more active than carbobenzoxyl-valinyl-phenylalanal. In immunoprecipitation experiments using antibodies directed toward either Abeta1-40 or Abeta1-42, 3,5-dimethoxycinnamamide-isoleucinyl-leucinal, like carbobenzoxyl-valinyl-phenylalanal, preferentially inhibited the shorter 1-40 form of Abeta, whereas the longer 1-42 form was not as strongly inhibited. These results suggest that dipeptide aldehydes related to carbobenzoxyl-valinyl-phenylalanal inhibit Abeta through similar mechanisms and demonstrate the utility of a combinatorial synthesis approach to rapidly identify potent inhibitors of Abeta production.
Asunto(s)
Aldehídos , Péptidos beta-Amiloides/biosíntesis , Dipéptidos/síntesis química , Biblioteca de Péptidos , Animales , Sitios de Unión , Células CHO , Línea Celular , Cricetinae , Humanos , Técnicas para Inmunoenzimas , Espectrometría de Masas , Modelos QuímicosRESUMEN
This study describes the anti-inflammatory actions of NPC 18884, a non-peptide bradykinin B2 receptor antagonist in bradykinin and carrageenan-induced inflammation in the mouse model of pleurisy. The selectivity of NPC 18884 was assessed in the pleurisy caused by histamine, substance P and des-Arg9-bradykinin. NPC 18884 given intraperitoneally or orally inhibited bradykinin-induced leukocytes influx (ID50 value of 63 nmol/kg and 141 nmol/kg, respectively). The NPC 18884 also inhibited the exudation induced by bradykinin (P < 0.05). NPC 18884 given either intraperitoneally or orally caused dose-dependent inhibition of the exudation and total and differential cell content caused by intrapleural injection of carrageenan (1%, assessed 4 h after), with mean ID50, values of 132 and 295 nmol/kg, respectively. The NPC 18884 actions installs rapidly (0.5 h), lasted for up to 4 h and were selective for the bradykinin B2 receptors; at similar doses it had no significant effect against the inflammatory responses induced by des-Arg9-bradykinin, histamine or substance P. These results indicate that the novel non-peptide bradykinin B2 receptor antagonist, NPC 18884, exhibited selective intraperitoneal and oral anti-inflammatory properties when assessed in the inflammatory reaction induced by bradykinin and carrageenan in the mice model of pleurisy.
Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Antagonistas de los Receptores de Bradiquinina , Dipéptidos/uso terapéutico , Pleuresia/prevención & control , Administración Oral , Animales , Antiinflamatorios no Esteroideos/administración & dosificación , Bradiquinina/análogos & derivados , Carragenina , Dipéptidos/farmacología , Modelos Animales de Enfermedad , Interacciones Farmacológicas , Femenino , Histamina , Masculino , Ratones , Pleuresia/inducido químicamente , Receptor de Bradiquinina B2 , Sustancia PRESUMEN
A simple and general approach to the synthesis of chemical libraries based on a universal anhydride template allows the preparation of large number of compounds. Various cyclic/acyclic amines, primary/secondary amines, differentially protected bifunctional amines were used as nucleophiles to react with anhydrides. The free carboxylic acid generated was then coupled with solid-bound amines. The facile and rapid generation of compounds through this multi-component assembly can be accomplished in a combinatorial parallel synthesis.
Asunto(s)
Amidas/química , Anhídridos/química , Acilación , Aminas/química , Aminoácidos/metabolismo , Fluorenos/metabolismo , Estructura Molecular , Resinas de PlantasRESUMEN
The novel pseudopeptide bradykinin B2 receptor antagonist containing the 1,3,8-triazaspiro[4,5]decan-4-one ring system, NPC 18521 (D-Arg-Arg-[1,3-phenyl,8-triazaspiro[4,5]-decane-4-one-3-acetyl]-S er-D -tetrahydroisoquinolinyl-octahydroindolinyl-Arg) (10 and 30 nmol/kg, i.p.), given 30 min prior, produced significant and long-lasting inhibition of rat paw oedema induced by bradykinin (3 nmol/paw) and carrageenan (300 micrograms/paw), without affecting the oedema induced by the selective bradykinin B1 receptor agonist, des-Arg9-bradykinin, in rats pretreated with Escherichia coli endotoxin. In contrast, when injected locally into the rat or mouse hindpaw, NPC 18521 (1-100 nmol) elicited dose-related oedema formation. This effect was almost completely blocked by cyproheptadine (20 mg/kg, i.p.) or by compound 48/80 (12 micrograms/paw), but was unaffected by Hoe 140 (D-Arg-[Hyp5,Thi5,Tic7,Oic8]bradykinin). NPC 18521 (0.3-10 nmol/kg, i.p.) produced significant inhibition of acetic acid, acetylcholine and kaolin- but not zymosan-induced abdominal constrictions in mice. The calculated mean ID50 values for these effects were 0.84, 0.46 and 0.55 nmol/kg, respectively. The antinociceptive action of NPC 18521 (3 nmol/kg, i.p.) had a rapid onset (15 min) and lasted for up to 120 min. Given topically (0.01-0.3 nmol), NPC 18521 produced significant attenuation of both the early and the late phase of the formalin-induced licking, as well as formalin-induced oedema formation. In addition, NPC 18521 given both systemically or topically, produced significant inhibition of the neurogenic nociception caused by topical injection of capsaicin. Given topically in the rat paw, NPC 18521 (10 nmol) caused marked hyperalgesia, an effect which was completely prevented by cyproheptadine (20 mg/kg, i.p.), but was unaffected by Hoe 140 (3 nmol/kg, i.p.). Given intraperitoneally, 30 min prior, NPC 18521 (3-30 nmol/kg) like Hoe 140 (1-10 nmol/kg) prevented, in a dose-dependent manner, bradykinin (3 nmol/paw)-induced hyperalgesia with mean ID50 values of 13.16 and 1.36 nmol/kg, respectively. Thus, the novel pseudopeptide bradykinin B2 receptor antagonist, NPC 18521, has an effect with rapid onset, and produces potent and relatively long-lasting antioedematogenic and antinociceptive properties. However, in contrast to Hoe 140, given locally into the hindpaw, NPC 18521 elicited marked oedema formation and hyperalgesia, an effect which seems to be secondary to mast cell degranulation and histamine and/or serotonin release. Finally, the anti-bradykinin actions of NPC 18521 are quite selective towards the bradykinin B2 receptor-mediated responses.
Asunto(s)
Bradiquinina/farmacología , Edema/tratamiento farmacológico , Imidazoles/farmacología , Dolor/tratamiento farmacológico , Compuestos de Espiro/farmacología , Animales , Relación Dosis-Respuesta a Droga , Masculino , Ratones , Dimensión del Dolor , Ratas , Ratas WistarRESUMEN
A series of pseudopeptides containing alkyl-, cycloalkyl-, aryl-, and aralkyl-substituted 1,3,8-triazaspiro[4.5]decan-4-one-3-acetic acids as amino acid surrogates to replace the Pro2-Pro3-Gly4-Phe5 section of the peptide bradykinin B2 receptor antagonist [Pro3, Phe5]HOE 140 (D-Arg0-Arg1-Pro2-Pro3-Gly4-Phe5-Ser6-D-Tic7+ ++-Oic8-Arg9) were prepared. These psuedopeptides were examined in vitro for their B2 receptor affinities as well as for their ability to block bradykinin mediated actions in vivo. Two compounds in particular, NPC 18521 (I) and NPC 18688 (V) were quite potent in these latter assays, indicating that a significant portion of this prototypical second generation decapeptide antagonist can be replaced with a more compact nonpeptide molecule.
Asunto(s)
Antagonistas de los Receptores de Bradiquinina , Imidazoles/síntesis química , Compuestos de Espiro/síntesis química , Secuencia de Aminoácidos , Animales , Unión Competitiva , Presión Sanguínea/efectos de los fármacos , Bradiquinina/antagonistas & inhibidores , Células CHO , Membrana Celular/efectos de los fármacos , Cricetinae , Imidazoles/química , Imidazoles/metabolismo , Imidazoles/farmacología , Datos de Secuencia Molecular , Estructura Molecular , Oligopéptidos/metabolismo , Conejos , Ratas , Ratas Sprague-Dawley , Receptor de Bradiquinina B2 , Compuestos de Espiro/química , Compuestos de Espiro/metabolismo , Compuestos de Espiro/farmacología , Relación Estructura-ActividadAsunto(s)
Antagonistas de los Receptores de Bradiquinina , Diseño de Fármacos , Animales , Sitios de Unión , Células CHO , Cricetinae , Evaluación Preclínica de Medicamentos , Humanos , Ligandos , Estructura Molecular , Oligopéptidos/química , Oligopéptidos/farmacología , Receptor de Bradiquinina B2 , Receptores de Bradiquinina/metabolismoRESUMEN
Two novel oxime derivatives of naltrexone, 6-[2-phenylethyl]-oximino naltrexone (NPC 831) and 6-[3-phenylpropyl]-oximino naltrexone (NPC 836) were potent agonists at opioid receptors. Both compounds inhibited binding to all three opioid receptor subtypes with nanomolar affinities. In vivo, NPC 831 and NPC 836 were equipotent to morphine and more potent than the kappa-selective agonist U-50,488H to produce analgesia. ED50 values of 4.02 mg/kg for NPC 831 and 2.24 mg/kg for NPC 836 were generated for inhibition of the tail-flick response in the rat, and ED50 values of 0.05 mg/kg for NPC 831 and 0.02 mg/kg for NPC 836 were calculated for inhibition of the writhing response in the mouse. Bombesin-induced scratching was used to evaluate NPC 831 and NPC 836 for kappa-agonist properties, and the A50, defined as the percent antagonism of the bombesin-induced response, was 1.86 mg/kg for NPC 831 and 0.08 mg/kg for NPC 836, compared to an A50 of 1.54 mg/kg for U-50,488H. These data suggest that NPC 831 and NPC 836 possess potent mu- and kappa-agonist properties in vivo, with NPC 836 being approximately twice as potent as NPC 831 to produce analgesia and 20 times as potent as NPC 831 to inhibit the scratching response produced by bombesin.
Asunto(s)
Naltrexona/análogos & derivados , Oximas/farmacología , Receptores Opioides/efectos de los fármacos , 3,4-Dicloro-N-metil-N-(2-(1-pirrolidinil)-ciclohexil)-bencenacetamida, (trans)-Isómero , Acetatos , Analgésicos/metabolismo , Analgésicos/farmacología , Animales , Unión Competitiva , Bombesina , Encefalina Ala(2)-MeFe(4)-Gli(5) , Leucina Encefalina-2-Alanina/metabolismo , Encefalinas/metabolismo , Cobayas , Ligandos , Masculino , Ratones , Naltrexona/farmacología , Dolor/inducido químicamente , Pirrolidinas/farmacología , Ratas , Ratas Sprague-Dawley , Tiempo de Reacción/efectos de los fármacos , Receptores Opioides kappa/efectos de los fármacosRESUMEN
NPC 168 (naltrexone phenyl oxime) was synthesized as a novel opioid antagonist and evaluated in several in vitro and in vivo assays. NPC 168 inhibited binding to the mu, delta and kappa subtypes of the opioid receptor with nanomolar potencies. The potency of NPC 168 to antagonize morphine-induced analgesia was slightly less than that of naltrexone and nalmefene following either intraperitoneal (ED50 = 0.07 mg/kg) or oral (ED50 = 0.82 mg/kg) administration. The duration of action of NPC 168 was approximately 8 hr following subcutaneous administration, compared to 4 hr for nalmefene, to antagonize oxymorphonazine-induced analgesia. The long duration of action of NPC 168 was substantiated by pharmacokinetic data that demonstrated rapid uptake and slow clearance of NPC 168 from brain. NPC 168 (5, 10 and 20 mg/kg) also inhibited cumulative 6-hr food intake in rats that were deprived of food for 24 hr, but chronic administration of this compound to rats over a three-week period resulted in a marginal reduction in cumulative body weight gain. NPC 168 at doses of up to 10 mg/kg did not produce a conditioned taste aversion. However, NPC 168 was slightly more toxic than either naltrexone or nalmefene when administered parenterally, and as toxic as nalmefene when administered by the oral route. These data demonstrate that NPC 168 is a novel opioid antagonist with a longer duration of action than either naltrexone or nalmefene.
Asunto(s)
Naltrexona/análogos & derivados , Naltrexona/farmacología , Antagonistas de Narcóticos , Animales , Unión Competitiva/efectos de los fármacos , Encefalina Ala(2)-MeFe(4)-Gli(5) , Leucina Encefalina-2-Alanina/metabolismo , Encefalinas/metabolismo , Privación de Alimentos , Cobayas , Inyecciones Intraventriculares , Masculino , Ratones , Morfina/farmacología , Naltrexona/toxicidad , Antagonistas de Narcóticos/farmacología , Ratas , Ratas Endogámicas , Tiempo de Reacción/efectos de los fármacos , Esquema de RefuerzoRESUMEN
A series of quaternary 2-phenylimidazo[1,2-a]pyridinum salts has been prepared and evaluated for antiparasitic activity. Primary attention was focused on derivatives with amido, substituted hydrazone, and heterocyclic functionality at the para position of the phenyl substituent. Guanylhydrazones and N-substituted guanylhydrazones of the 4'-formyl-substituted compounds are very active against the blood state Trypanosoma rhodesiense in mice by subcutaneous or oral administration. The most potent compounds attain 100% survival for 30 days at doses of less than 1.0 mg/kg (sc) and greater than 5.0 mg/kg (po). Weaker activity is noted for certain other 4'-substituents such as carboxamidines and carboxamide oximes. Considerable variation in structure, including replacing of the imidazo [1,2-a]pyridinium ring by other cationic heterocyclic rings and insertion of linking groups between the heterocyclic ring and phenyl group, can be done, and a high level of activity is maintained. Relationships between these structural changes and biological activity are discussed.