RESUMEN
Xiakucao Oral Liquid (XKCOL) has been widely used for treating mammary gland hyperplasia and goiter in China. However, its pharmacokinetic data have been missing to date. To conduct its pharmacokinetic study, we established an LC-tandem mass spectrometry method for the simultaneous determination of eight XKCOL-related compounds in rat plasma. Liquid-liquid extraction was used for the sampling process. Chromatographic separation was performed on a Phenomenon Luna C18 column with a mobile phase of methanol and 2 mM ammonium acetate, using gradient elution at a flow rate of 0.8 mL/min. Detection was performed in the multiple reaction monitoring mode using negative electrospray ionization (ESI-) with optimized MS parameters. Endogenous substances and carryover did not interfere in the detection of analytes. The calibration curves showed a good linear relationship within the linear ranges. The intra- and inter-batch accuracy and precision were 94.8%-110.0% and ≤11.2%, respectively. There was no significant matrix effect and the recovery was reproducible. The dilution of samples did not affect the accuracy and precision. The solution and plasma samples were stable under the various test conditions. The major components of XKCOL absorbed into the blood were salvianic acid A and rosmarinic acid. They demonstrated linear kinetics over the dose range used in this study.
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Medicamentos Herbarios Chinos , Ratas Sprague-Dawley , Espectrometría de Masas en Tándem , Animales , Espectrometría de Masas en Tándem/métodos , Ratas , Medicamentos Herbarios Chinos/farmacocinética , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/administración & dosificación , Reproducibilidad de los Resultados , Modelos Lineales , Cromatografía Liquida/métodos , Límite de Detección , Masculino , Extracción Líquido-Líquido/métodos , Sensibilidad y EspecificidadRESUMEN
Compelling evidence suggests that synaptic structural plasticity, driven by remodeling of the actin cytoskeleton, underlies addictive drugs-induced long-lasting behavioral plasticity. However, the signaling mechanisms leading to actin cytoskeleton remodeling remain poorly defined. DNA methylation is a critical mechanism used to control activity-dependent gene expression essential for long-lasting synaptic plasticity. Here, we provide evidence that DNA methyltransferase DNMT3a is degraded by the E2 ubiquitin-conjugating enzyme Ube2b-mediated ubiquitination in dorsal hippocampus (DH) of rats that repeatedly self-administrated heroin. DNMT3a degradation leads to demethylation in CaMKK1 gene promotor, thereby facilitating CaMKK1 expression and consequent activation of its downstream target CaMKIα, an essential regulator of spinogenesis. CaMKK1/CaMKIα signaling regulates actin cytoskeleton remodeling in the DH and behavioral plasticity by activation of Rac1 via acting Rac guanine-nucleotide-exchange factor ßPIX. These data suggest that Ube2b-dependent degradation of DNMT3a relieves a transcriptional brake on CaMKK1 gene and thus activates CaMKK1/CaMKIα/ßPIX/Rac1 cascade, leading to drug use-induced actin polymerization and behavior plasticity.
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ADN (Citosina-5-)-Metiltransferasas , Alcaloides Opiáceos , Enzimas Ubiquitina-Conjugadoras , Animales , Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina , ADN Metiltransferasa 3A , Factores de Intercambio de Guanina Nucleótido , Hipocampo , Plasticidad Neuronal/genética , Ratas , Transducción de SeñalRESUMEN
Extinction of aversive memories has been a major concern in neuropsychiatric disorders, such as anxiety disorders and drug addiction. However, the mechanisms underlying extinction of aversive memories are not fully understood. Here, we report that extinction of conditioned place aversion (CPA) to naloxone-precipitated opiate withdrawal in male rats activates Rho GTPase Rac1 in the ventromedial prefrontal cortex (vmPFC) in a BDNF-dependent manner, which determines GABAA receptor (GABAAR) endocytosis via triggering synaptic translocation of activity-regulated cytoskeleton-associated protein (Arc) through facilitating actin polymerization. Active Rac1 is essential and sufficient for GABAAR endocytosis and CPA extinction. Knockdown of Rac1 expression within the vmPFC of rats using Rac1-shRNA suppressed GABAAR endocytosis and CPA extinction, whereas expression of a constitutively active form of Rac1 accelerated GABAAR endocytosis and CPA extinction. The crucial role of GABAAR endocytosis in the LTP induction and CPA extinction is evinced by the findings that blockade of GABAAR endocytosis by a dynamin function-blocking peptide (Myr-P4) abolishes LTP induction and CPA extinction. Thus, the present study provides first evidence that Rac1-dependent GABAAR endocytosis plays a crucial role in extinction of aversive memories and reveals the sequence of molecular events that contribute to learning experience modulation of synaptic GABAAR endocytosis.SIGNIFICANCE STATEMENT This study reveals that Rac1-dependent GABAAR endocytosis plays a crucial role in extinction of aversive memories associated with drug withdrawal and identifies Arc as a downstream effector of Rac1 regulations of synaptic plasticity as well as learning and memory, thereby suggesting therapeutic targets to promote extinction of the unwanted memories.
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Reacción de Prevención/fisiología , Endocitosis/fisiología , Extinción Psicológica/fisiología , Memoria/fisiología , Corteza Prefrontal/fisiología , Receptores de GABA-A/metabolismo , Proteína de Unión al GTP rac1/metabolismo , Animales , Masculino , Recuerdo Mental/fisiología , Ratas , Ratas Sprague-Dawley , Represión PsicológicaRESUMEN
Metabolic reprogramming in tumors represents a potential therapeutic target. Herein we used shRNA depletion and a novel lactate dehydrogenase (LDHA) inhibitor, GNE-140, to probe the role of LDHA in tumor growth in vitro and in vivo. In MIA PaCa-2 human pancreatic cells, LDHA inhibition rapidly affected global metabolism, although cell death only occurred after 2 d of continuous LDHA inhibition. Pancreatic cell lines that utilize oxidative phosphorylation (OXPHOS) rather than glycolysis were inherently resistant to GNE-140, but could be resensitized to GNE-140 with the OXPHOS inhibitor phenformin. Acquired resistance to GNE-140 was driven by activation of the AMPK-mTOR-S6K signaling pathway, which led to increased OXPHOS, and inhibitors targeting this pathway could prevent resistance. Thus, combining an LDHA inhibitor with compounds targeting the mitochondrial or AMPK-S6K signaling axis may not only broaden the clinical utility of LDHA inhibitors beyond glycolytically dependent tumors but also reduce the emergence of resistance to LDHA inhibition.
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Plasticidad de la Célula/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , L-Lactato Deshidrogenasa/antagonistas & inhibidores , Piridonas/farmacología , Tiofenos/farmacología , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/química , Humanos , L-Lactato Deshidrogenasa/metabolismo , Modelos Moleculares , Estructura Molecular , Piridonas/química , Relación Estructura-Actividad , Tiofenos/químicaRESUMEN
A novel, potent, and orally bioavailable inhibitor of the bromodomain of CBP, compound 35 (GNE-207), has been identified through SAR investigations focused on optimizing al bicyclic heteroarene to replace the aniline present in the published GNE-272 series. Compound 35â¯has excellent CBP potency (CBP IC50â¯=â¯1â¯nM, MYC EC50â¯=â¯18â¯nM), a selectively index ofâ¯>2500-fold against BRD4(1), and exhibits a good pharmacokinetic profile.
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Compuestos de Bifenilo/química , Diseño de Fármacos , Factores de Transcripción p300-CBP/antagonistas & inhibidores , Animales , Sitios de Unión , Compuestos de Bifenilo/síntesis química , Compuestos de Bifenilo/metabolismo , Proteínas de Ciclo Celular , Cristalografía por Rayos X , Semivida , Humanos , Enlace de Hidrógeno , Concentración 50 Inhibidora , Ratones , Microsomas Hepáticos/metabolismo , Simulación de Dinámica Molecular , Proteínas Nucleares/antagonistas & inhibidores , Proteínas Nucleares/metabolismo , Estructura Terciaria de Proteína , Ratas , Relación Estructura-Actividad , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/metabolismo , Factores de Transcripción p300-CBP/metabolismoRESUMEN
Addiction is characterized by drug craving, compulsive drug taking and relapse, which is attributed to aberrant neuroadaptation in brain regions implicated in drug addiction, induced by changes in gene and protein expression in these regions after chronic drug exposure. Accumulating evidence suggests that the dorsal hippocampus (DH) plays an important role in mediating drug-seeking and drug-taking behavior and relapse. However, the molecular mechanisms underlying these effects of the DH are unclear. In the present study, we employed a label-free quantitative proteomic approach to analyze the proteins altered in the DH of heroin self-administering rats. A total of 4015 proteins were quantified with high confidence, and 361 proteins showed significant differences compared with the saline control group. Among them, cyclin-dependent kinase 5 (CDK5) and ras homolog family member B (RhoB) were up-regulated in rats with a history of extended access to heroin. Functionally, inhibition of CDK5 in the DH enhanced heroin self-administration, indicating that CDK5 signaling in the DH acts as a homeostatic compensatory mechanism to limit heroin-taking behavior, whereas blockade of the Rho-Rho kinase (ROCK) pathway attenuated context-induced heroin relapse, indicating that RhoB signaling in the DH is required for the retrieval (recall) of addiction memory. Our findings suggest that manipulation of CDK5 signaling in the DH may be essential in determining vulnerability to opiate taking, whereas manipulation of RhoB signaling in the DH may be essential in determining vulnerability to relapse. Overall, the present study suggests that the DH can exert dissociative effects on heroin addiction through CDK5 and RhoB signaling.
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Quinasa 5 Dependiente de la Ciclina/metabolismo , Dependencia de Heroína/fisiopatología , Heroína/farmacología , Hipocampo/metabolismo , Transducción de Señal/efectos de los fármacos , Proteína de Unión al GTP rhoB/metabolismo , Animales , Conducta Animal/efectos de los fármacos , Quinasa 5 Dependiente de la Ciclina/efectos de los fármacos , Quinasa 5 Dependiente de la Ciclina/genética , Modelos Animales de Enfermedad , Comportamiento de Búsqueda de Drogas/efectos de los fármacos , Heroína/administración & dosificación , Dependencia de Heroína/genética , Dependencia de Heroína/metabolismo , Hipocampo/efectos de los fármacos , Masculino , Narcóticos/administración & dosificación , Narcóticos/farmacología , Proteómica/métodos , Ratas , Ratas Sprague-Dawley , Recurrencia , Autoadministración , Proteína de Unión al GTP rhoB/efectos de los fármacos , Proteína de Unión al GTP rhoB/genéticaRESUMEN
Immunosuppression caused by incomplete radiofrequency ablation (iRFA) is a crucial factor affecting the effectiveness of RFA for solid tumors. However, little is known about the changes iRFA induces in the tumor immune microenvironment (TIME) of hepatocellular carcinoma (HCC), the primary application area for RFA. In this study, we found iRFA promotes a suppressive TIME in residual HCC tumors, characterized by M2 macrophage polarization, inhibited antigen presentation by dendritic cells (DCs), and reduced infiltration of cytotoxic T lymphocytes (CTLs). Interestingly, the STING agonist MSA-2 was able to reorganize M2-like tumor-promoting macrophages into M1-like anti-tumor states and enhance antigen presentation by DCs. To optimize the therapeutic effect of MSA-2, we used a calcium ion (Ca2+) responsive sodium alginate (ALG) as a carrier, forming an injectable hydrogel named ALG@MSA-2. This hydrogel can change from liquid to gel, maintaining continuous drug release in situ. Our results suggested that ALG@MSA-2 effectively activated anti-tumor immunity, as manifested by increased M1-like macrophage polarization, enhanced antigen presentation by DCs, increased CTL infiltration, and inhibited residual tumor growth. ALG@MSA-2 also resulted in a complete regression of contralateral tumors and widespread liver metastases in vivo. In addition, the excellent biosafety of ALG@MSA-2 was also proved by blood biochemical analysis and body weight changes in mice. In summary, this study demonstrated that the immune cascade of ALG@MSA-2 mediated the STING pathway activation and promoted a favorable TIME which might provide novel insights for the RFA treatment of HCC.
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Alginatos , Carcinoma Hepatocelular , Hidrogeles , Neoplasias Hepáticas , Proteínas de la Membrana , Ratones Endogámicos C57BL , Ablación por Radiofrecuencia , Animales , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/terapia , Hidrogeles/administración & dosificación , Ablación por Radiofrecuencia/métodos , Alginatos/química , Alginatos/administración & dosificación , Células Dendríticas/efectos de los fármacos , Células Dendríticas/inmunología , Línea Celular Tumoral , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Microambiente Tumoral/efectos de los fármacos , Ratones , Masculino , Linfocitos T Citotóxicos/efectos de los fármacos , Linfocitos T Citotóxicos/inmunología , HumanosRESUMEN
BACKGROUND: To evaluate the efficacy and safety of Ningmitai (NMT) capsule for treating chronic prostatitis (CP) in China. METHODS: Retrieving the China Journal Full-Text Database (CNKI), Wanfang database, China's outstanding master's/doctoral dissertation database, VIP Science and Technology Periodical Database, Cochrane library, PubMed, Embase, and Chinese academic conference papers. Collecting and selecting literatures of randomized controlled trials before March 2017 on NMT capsule for CP, evaluated by Jadad scale, and then analyzed with Stata software. RESULTS: Thirty randomized clinical trials including 6185 patients (3124 in the test group and 3061 in the control group) were included. The overall treatment risk ratios (RRs) were 1.19 (1.14, 1.24). The merged RRs were 1.05 (0.95, 1.15) and 1.22 (1.19, 1.26) for the single-drug group and the combined-drug group, respectively. The adverse events were found to be lower in all groups. CONCLUSION: NMT is effective and safety on the treatment of CP, especially in combined-drug groups. High quality and a good design of multicentered, randomized, parallel-controlled and blinding trials are needed in order to make further studies, and deserve further examination for the treatment of CP with NMT.
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Medicamentos Herbarios Chinos/uso terapéutico , Fitoterapia , Prostatitis/tratamiento farmacológico , Adulto , China , Enfermedad Crónica , Humanos , Masculino , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento , Adulto JovenRESUMEN
The epigenetic regulator CBP/P300 presents a novel therapeutic target for oncology. Previously, we disclosed the development of potent and selective CBP bromodomain inhibitors by first identifying pharmacophores that bind the KAc region and then building into the LPF shelf. Herein, we report the "hybridization" of a variety of KAc-binding fragments with a tetrahydroquinoline scaffold that makes optimal interactions with the LPF shelf, imparting enhanced potency and selectivity to the hybridized ligand. To demonstrate the utility of our hybridization approach, two analogues containing unique Asn binders and the optimized tetrahydroquinoline moiety were rapidly optimized to yield single-digit nanomolar inhibitors of CBP with exquisite selectivity over BRD4(1) and the broader bromodomain family.
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Ensayos Analíticos de Alto Rendimiento/métodos , Factores de Transcripción p300-CBP/antagonistas & inhibidores , Animales , Asparagina/química , Asparagina/metabolismo , Sitios de Unión , Proteínas de Ciclo Celular , Cristalografía por Rayos X , Femenino , Transferencia Resonante de Energía de Fluorescencia/métodos , Ratones Endogámicos , Simulación del Acoplamiento Molecular , Proteínas Nucleares/antagonistas & inhibidores , Dominios Proteicos , Pirazoles/química , Piridinas/química , Quinolinas/química , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción p300-CBP/química , Factores de Transcripción p300-CBP/metabolismoRESUMEN
Inhibition of the bromodomain of the transcriptional regulator CBP/P300 is an especially interesting new therapeutic approach in oncology. We recently disclosed in vivo chemical tool 1 (GNE-272) for the bromodomain of CBP that was moderately potent and selective over BRD4(1). In pursuit of a more potent and selective CBP inhibitor, we used structure-based design. Constraining the aniline of 1 into a tetrahydroquinoline motif maintained potency and increased selectivity 2-fold. Structure-activity relationship studies coupled with further structure-based design targeting the LPF shelf, BC loop, and KAc regions allowed us to significantly increase potency and selectivity, resulting in the identification of non-CNS penetrant 19 (GNE-781, TR-FRET IC50 = 0.94 nM, BRET IC50 = 6.2 nM; BRD4(1) IC50 = 5100 nΜ) that maintained good in vivo PK properties in multiple species. Compound 19 displays antitumor activity in an AML tumor model and was also shown to decrease Foxp3 transcript levels in a dose dependent manner.
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Antineoplásicos/farmacología , Proteína de Unión a CREB/antagonistas & inhibidores , Pirazoles/farmacología , Piridinas/farmacología , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Antineoplásicos/farmacocinética , Proteína de Unión a CREB/química , Perros , Femenino , Factores de Transcripción Forkhead/genética , Factores de Transcripción Forkhead/metabolismo , Células HEK293 , Humanos , Macaca fascicularis , Masculino , Ratones , Dominios Proteicos , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Pirazoles/síntesis química , Pirazoles/química , Pirazoles/farmacocinética , Piridinas/síntesis química , Piridinas/química , Piridinas/farmacocinética , ARN/genética , Ratas Sprague-Dawley , Relación Estructura-Actividad , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Current treatment of toxoplasmosis targets the parasite's folate metabolism through inhibition of dihydrofolate reductase (DHFR). The most widely used DHFR antagonist, pyrimethamine, was introduced over 60 years ago and is associated with toxicity that can be largely attributed to a similar affinity for parasite and human DHFR. Computational analysis of biochemical differences between Toxoplasma gondii and human DHFR enabled the design of inhibitors with both improved potency and selectivity. The approach described herein yielded TRC-19, a promising lead with an IC50 of 9 nM and 89-fold selectivity in favor of Toxoplasma gondii DHFR, as well as crystallographic data to substantiate in silico methodology. Overall, 50% of synthesized in silico designs met hit threshold criteria of IC50 < 10 µM and >2-fold selectivity favoring Toxoplasma gondii, further demonstrating the efficiency of our structure-based drug design approach.
RESUMEN
The single bromodomain of the closely related transcriptional regulators CBP/EP300 is a target of much recent interest in cancer and immune system regulation. A co-crystal structure of a ligand-efficient screening hit and the CBP bromodomain guided initial design targeting the LPF shelf, ZA loop, and acetylated lysine binding regions. Structure-activity relationship studies allowed us to identify a more potent analogue. Optimization of permeability and microsomal stability and subsequent improvement of mouse hepatocyte stability afforded 59 (GNE-272, TR-FRET IC50 = 0.02 µM, BRET IC50 = 0.41 µM, BRD4(1) IC50 = 13 µM) that retained the best balance of cell potency, selectivity, and in vivo PK. Compound 59 showed a marked antiproliferative effect in hematologic cancer cell lines and modulates MYC expression in vivo that corresponds with antitumor activity in an AML tumor model.
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Antineoplásicos/farmacología , Descubrimiento de Drogas , Pirazoles/farmacología , Piridonas/farmacología , Factores de Transcripción p300-CBP/antagonistas & inhibidores , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Perros , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Células de Riñón Canino Madin Darby , Ratones , Ratones Desnudos , Modelos Moleculares , Estructura Molecular , Pirazoles/síntesis química , Pirazoles/química , Piridonas/síntesis química , Piridonas/química , Relación Estructura-ActividadRESUMEN
A series of trisubstituted hydroxylactams was identified as potent enzymatic and cellular inhibitors of human lactate dehydrogenase A. Utilizing structure-based design and physical property optimization, multiple inhibitors were discovered with <10 µM lactate IC50 in a MiaPaca2 cell line. Optimization of the series led to 29, a potent cell active molecule (MiaPaca2 IC50 = 0.67 µM) that also possessed good exposure when dosed orally to mice.
RESUMEN
CBP and EP300 are highly homologous, bromodomain-containing transcription coactivators involved in numerous cellular pathways relevant to oncology. As part of our effort to explore the potential therapeutic implications of selectively targeting bromodomains, we set out to identify a CBP/EP300 bromodomain inhibitor that was potent both in vitro and in cellular target engagement assays and was selective over the other members of the bromodomain family. Reported here is a series of cell-potent and selective probes of the CBP/EP300 bromodomains, derived from the fragment screening hit 4-methyl-1,3,4,5-tetrahydro-2H-benzo[b][1,4]diazepin-2-one.
RESUMEN
Herein, we describe the development of a functionally selective liver X receptor ß (LXRß) agonist series optimized for Emax selectivity, solubility, and physical properties to allow efficacy and safety studies in vivo. Compound 9 showed central pharmacodynamic effects in rodent models, evidenced by statistically significant increases in apolipoprotein E (apoE) and ATP-binding cassette transporter levels in the brain, along with a greatly improved peripheral lipid safety profile when compared to those of full dual agonists. These findings were replicated by subchronic dosing studies in non-human primates, where cerebrospinal fluid levels of apoE and amyloid-ß peptides were increased concomitantly with an improved peripheral lipid profile relative to that of nonselective compounds. These results suggest that optimization of LXR agonists for Emax selectivity may have the potential to circumvent the adverse lipid-related effects of hepatic LXR activity.
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Transportadoras de Casetes de Unión a ATP/metabolismo , Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides/líquido cefalorraquídeo , Apolipoproteínas E/líquido cefalorraquídeo , Benzamidas/química , Benzamidas/farmacología , Receptores Nucleares Huérfanos/agonistas , Piperidinas/química , Piperidinas/farmacología , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Perros , Células Hep G2 , Humanos , Lípidos/análisis , Hígado/efectos de los fármacos , Hígado/metabolismo , Receptores X del Hígado , Locomoción/efectos de los fármacos , Macaca mulatta , Células de Riñón Canino Madin Darby , Ratones , Ratones TransgénicosRESUMEN
BACKGROUND AND PURPOSE: Substantial evidence shows that negative reinforcement resulting from the aversive affective consequences of opiate withdrawal may play a crucial role in drug relapse. Understanding the mechanisms underlying the loss (extinction) of conditioned aversion of drug withdrawal could facilitate the treatment of drug addiction. EXPERIMENTAL APPROACH: Naloxone-induced conditioned place aversion (CPA) of Sprague-Dawley rats was used to measure conditioned aversion. An NMDA receptor antagonist and MAPK kinase inhibitor were applied through intracranial injections. The phosphorylation of ERK and cAMP response element-binding protein (CREB) was detected using Western blot. KEY RESULTS: The extinction of CPA behaviour increased the phosphorylation of ERK and CREB in the dorsal hippocampus (DH) and basolateral amygdala (BLA), but not in the central amygdala (CeA). Intra-DH injection of AP5 or intra-BLA injection of AP-5 or U0126 before extinction training significantly attenuated ERK and CREB phosphorylation in the BLA and impaired the extinction of CPA behaviour. Although intra-DH injections of AP-5 attenuated extinction training-induced activation of the ERK-CREB pathway in the BLA, intra-BLA injection of AP5 had no effect on extinction training-induced activation of the ERK-CREB pathway in the DH. CONCLUSIONS AND IMPLICATIONS: These results suggest that activation of ERK and CREB in the BLA and DH is involved in the extinction of CPA behaviour and that the DH, via a direct or indirect pathway, modulates the activity of ERK and CREB in the BLA through activation of NMDA receptors after extinction training. Understanding the mechanisms underlying the extinction of conditioned aversion could facilitate the treatment of drug addiction. LINKED ARTICLES: This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2.
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Reacción de Prevención/fisiología , Complejo Nuclear Basolateral/fisiología , Condicionamiento Psicológico/fisiología , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/antagonistas & inhibidores , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Analgésicos Opioides/farmacología , Animales , Reacción de Prevención/efectos de los fármacos , Complejo Nuclear Basolateral/efectos de los fármacos , Complejo Nuclear Basolateral/metabolismo , Butadienos/farmacología , Condicionamiento Psicológico/efectos de los fármacos , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/fisiología , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/fisiología , Hipocampo/efectos de los fármacos , Hipocampo/fisiología , Masculino , Morfina/farmacología , Naloxona/farmacología , Antagonistas de Narcóticos/farmacología , Nitrilos/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Ratas Sprague-Dawley , Receptores de N-Metil-D-Aspartato/fisiologíaRESUMEN
A small molecule nonpeptide inhibitor of beta-secretase has been developed, and its binding has been defined through crystallographic determination of the enzyme-inhibitor complex. The molecule is shown to bind to the catalytic aspartate residues in an unprecedented manner in the field of aspartyl protease inhibition. Additionally, the complex reveals a heretofore unknown S(3) subpocket that is created by the inhibitor. This structure has served an important role in the design of newer beta-secretase inhibitors.
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Acetamidas/química , Ácido Aspártico Endopeptidasas/química , Benzamidas/química , Bencenosulfonatos/química , Inhibidores de Proteasas/química , Secretasas de la Proteína Precursora del Amiloide , Sitios de Unión , Técnicas Químicas Combinatorias , Cristalografía por Rayos X , Endopeptidasas , Enlace de Hidrógeno , Modelos Moleculares , Estructura Molecular , Estereoisomerismo , Relación Estructura-ActividadRESUMEN
Recent efforts in the field of thrombin inhibitor research have focused on the identification of compounds with good oral bioavailability and pharmacokinetics. In this manuscript we describe a metabolism-based approach to the optimization of the 3-(2-phenethylamino)-6-methylpyrazinone acetamide template (e.g., 1) which resulted in the modification of each of the three principal components (i.e., P1, P2, P3) comprising this series. As a result of these studies, several potent thrombin inhibitors (e.g., 20, 24, 25) were identified which exhibit high levels of oral bioavailability and long plasma half-lives.
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Acetamidas/farmacocinética , Anticoagulantes/farmacocinética , Inhibidores de Proteasas/síntesis química , Pirazinas/farmacocinética , Piridinas/farmacocinética , Trombina/antagonistas & inhibidores , Acetamidas/síntesis química , Acetamidas/farmacología , Administración Oral , Animales , Anticoagulantes/síntesis química , Anticoagulantes/farmacología , Disponibilidad Biológica , Cristalografía por Rayos X , Perros , Macaca mulatta , Modelos Moleculares , Inhibidores de Proteasas/química , Inhibidores de Proteasas/farmacología , Pirazinas/síntesis química , Pirazinas/farmacología , Piridinas/síntesis química , Piridinas/farmacología , Ratas , Relación Estructura-ActividadRESUMEN
AIMS: Although extensive investigation has revealed that an astrocyte-specific protein aquaporin-4 (AQP4) participates in regulating synaptic plasticity and memory, a functional relationship between AQP4 and learning processing has not been clearly established. This study was designed to test our hypothesis that AQP4 modulates the aversive motivation in Morris water maze (MWM). METHODS AND RESULTS: Using hidden platform training, we observed that AQP4 KO mice significantly decreased their swimming velocity compared with wild-type (WT) mice. To test for a relationship between velocities and escape motivation, we removed the platform and subjected a new group of mice similar to the session of hidden platform training. We found that KO mice exhibited a gradual reduction in swimming velocity, while WT mice did not alter their velocity. In the subsequent probe trial, KO mice after no platform training significantly decreased their mean velocity compared with those KO mice after hide platform training. However, all of KO mice were not impaired in their ability to locate a visible, cued escape platform. CONCLUSIONS: Our findings, along with a previous report that AQP4 regulates memory consolidation, implicate a novel role for this glial protein in modulating the aversive motivation in spatial learning paradigm.