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1.
Anim Reprod Sci ; 215: 106330, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32216931

RESUMO

The objective of this study was to investigate effects of selenium (Se) on proliferation and apoptosis of sheep spermatogonial stem cells (SSC) in vitro. The SSC were assigned to five treatment groups (0, 2.0, 4.0, 8.0 and 16.0 µmol/L Se). After treatment with Se for 96 h, cell proliferation and apoptosis were evaluated. The relative abundance of P53 mRNA transcript and protein, cell cycle and apoptosis-related genes were detected using real-time PCR and Western blot quantifications, respectively. The results indicate there were the least cell proliferation rates in the Se16.0 group. Treatments with relatively greater Se concentrations (8.0 and 16.0 µmol/L) resulted in a greater percentage of apoptotic cells, which was consistent with the relative abundances of P53, P21, P27 and pro-apoptosis mRNA transcripts. There were relatively greater ROS concentrations in the control, Se8.0 and Se16.0 groups. Compared with the control group, treatment with the Se concentration of 16.0 µmol/L resulted in an increased abundance of P53, P21, P27 and BAX proteins. Treatment with Pifithrin-α suppressed the increase in abundance of P53 and P21 proteins induced by the relatively greater concentration of Se (16.0 µmol/L), however, did not result in a change in abundances of P27 and BAX proteins. These results indicate the regulatory functions of Se on proliferation and apoptosis of sheep SSC is associated with the P21-mediated P53 signalling pathway. The P27 and BAX proteins have limited functions during the apoptotic process of SSC induced by the relatively greater concentrations of Se.


Assuntos
Células-Tronco Germinativas Adultas/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Selênio/farmacologia , Ovinos , Células-Tronco Germinativas Adultas/fisiologia , Animais , Benzotiazóis/administração & dosagem , Benzotiazóis/farmacologia , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Redução da Medicação , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Selênio/administração & dosagem , Tolueno/administração & dosagem , Tolueno/análogos & derivados , Tolueno/farmacologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
2.
J Mater Chem B ; 7(40): 6210-6223, 2019 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-31566200

RESUMO

Due to the complexity and heterogeneity of solid tumors, traditional clinical treatments often only achieve limited therapeutic effects. Tumor-associated macrophages (TAMs) play a key role in the development of solid tumors, and the elimination of solid tumors based on the tumor microenvironment has proven to be an effective therapeutic strategy. Here, we successfully developed Ru-based nanoparticles, Ru@ICG-BLZ NPs, with inflammation-responsive release ability, which could repolarize TAMs into M1 macrophages (with an antitumor role) and further produce hyperthermia and ROS to eliminate cancer cells. In vitro experiments showed that Ru@ICG-BLZ NPs had superior drug (ICG and BLZ-945) loading capacity and sensitive inflammation-responsive drug release behavior, which enhanced CT26 cell uptake and penetration ability. Furthermore, in vivo experiments showed that Ru@ICG-BLZ NPs could effectively up-regulate the expression of M1 markers (iNOS, and IL-12) and exert phototherapy to ablate solid tumor, without causing obvious damage to the surrounding tissues of the tumor. The lower toxicity and excellent antitumor ability of Ru@ICG-BLZ NPs could provide new ideas for the clinical transformation of nanomedicine.


Assuntos
Benzotiazóis/farmacologia , Neoplasias Colorretais/terapia , Inflamação/fisiopatologia , Macrófagos/imunologia , Nanopartículas/administração & dosagem , Fototerapia , Ácidos Picolínicos/farmacologia , Rutênio/química , Animais , Apoptose , Benzotiazóis/administração & dosagem , Benzotiazóis/química , Proliferação de Células , Neoplasias Colorretais/patologia , Liberação Controlada de Fármacos , Feminino , Humanos , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Ácidos Picolínicos/administração & dosagem , Ácidos Picolínicos/química , Nanomedicina Teranóstica , Células Tumorais Cultivadas , Microambiente Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Mar Drugs ; 17(7)2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31340514

RESUMO

Thirty-four new benzo[d]thiazol derivatives 2a-2i, 3a-3r, and 4a-4g were synthesized and investigated for their potential antidepressant and anticonvulsant effects. In a forced swimming test, 2c and 2d showed the highest antidepressant and anticonvulsant effects. 2c and 2d displayed a higher percentage decrease in immobility duration (89.96% and 89.62%, respectively) than that of fluoxetine (83.62%). In the maximal electroshock seizure test, 3n and 3q showed the highest anticonvulsant effect, with ED50 values of 46.1 and 64.3 mg kg-1, and protective indices of 6.34 and 4.11, respectively, which were similar to those of phenobarbital or valproate. We also found that the mechanism for the antidepressant activity of 2c and 2d may be via increasing the concentrations of serotonin and norepinephrine.


Assuntos
Anticonvulsivantes/administração & dosagem , Antidepressivos/administração & dosagem , Benzotiazóis/administração & dosagem , Produtos Biológicos/farmacologia , Depressão/tratamento farmacológico , Convulsões/tratamento farmacológico , Animais , Regiões Antárticas , Anticonvulsivantes/síntese química , Antidepressivos/síntese química , Organismos Aquáticos/química , Benzotiazóis/síntese química , Produtos Biológicos/síntese química , Produtos Biológicos/uso terapêutico , Depressão/etiologia , Depressão/psicologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Eletrochoque/efeitos adversos , Fluoxetina/administração & dosagem , Humanos , Injeções Intraperitoneais , Masculino , Camundongos , Camundongos Endogâmicos ICR , Penicillium/química , Convulsões/etiologia , Estresse Psicológico/complicações , Estresse Psicológico/psicologia , Testes de Toxicidade , Resultado do Tratamento , Ácido Valproico/administração & dosagem
4.
Br J Pharmacol ; 176(12): 2095-2108, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30825190

RESUMO

BACKGROUND AND PURPOSE: Necroptosis is a form of programmed, caspase-independent, cell death, mediated by receptor-interacting protein kinases, RIPK1 and RIPK3, and the mixed lineage kinase domain-like (MLKL). Necroptosis contributes to the pathophysiology of various inflammatory, infectious, and degenerative diseases. Thus, identification of low MW inhibitors for necroptosis has broad therapeutic relevance. Here, we identified that the pan-Raf inhibitor TAK-632 was also an inhibitor of necroptosis. We have further generated a more selective, highly potent analogue of TAK-632 by targeting RIPK1 and RIPK3. EXPERIMENTAL APPROACH: Cell viability was measured by MTT, propidium staining, or CellTiter-Glo luminescent assays. Effects of TAK-632 on necroptosis signalling pathways were investigated by western blotting, immunoprecipitation, and in vitro kinase assays. Downstream targets of TAK-632 were identified by a drug affinity responsive target stability assay and a pull-down assay with biotinylated TAK-632. A mouse model of TNF-α-induced systemic inflammatory response syndrome (SIRS) was further used to explore the role of TAK-632 in protecting against necroptosis-associated inflammation in vivo. KEY RESULTS: TAK-632 protected against necroptosis in human and mouse cells but did not protect cells from apoptosis. TAK-632 directly bound with RIPK1 and RIPK3 to inhibit kinase activities of both enzymes. In vivo, TAK-632 alleviated TNF-induced SIRS. Furthermore, we performed a structure-activity relationship analysis of TAK-632 analogues and generated SZM594, a highly potent inhibitor of RIPK1/3. CONCLUSIONS AND IMPLICATIONS: TAK-632 is an inhibitor of necroptosis and represents a new lead compound in the development of highly potent inhibitors of RIPK1 and RIPK3.


Assuntos
Benzotiazóis/farmacologia , Necroptose/efeitos dos fármacos , Nitrilas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Proteína Serina-Treonina Quinases de Interação com Receptores/antagonistas & inibidores , Animais , Benzotiazóis/administração & dosagem , Benzotiazóis/química , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Feminino , Células HEK293 , Células HT29 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Nitrilas/administração & dosagem , Nitrilas/química , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/química , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Relação Estrutura-Atividade
5.
World Neurosurg ; 117: e403-e410, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29913295

RESUMO

BACKGROUND: Postoperative epidural adhesion is a frequent cause of failed back surgery syndrome, manifesting with back and leg pain or neurologic deficits. Development of preventive measures for epidural adhesion after laminectomy is critical to improve outcomes of lumbar surgery. We hypothesized that positive effects of topical application of Contractubex (CTX) gel and benzothiazole (BT) individually and in combination could aid in preventing epidural fibrosis in a rat laminectomy model. METHODS: Rats were randomly assigned to 2 control and 5 experimental groups (n = 8 for each group). The control(-) group received no surgery, whereas the control(+) group underwent laminectomy without any drug administration. In experimental groups, study agents applied to dura mater after laminectomy were 100mgCTX, 2.5%BT, 5%BT; 100mgCTXplus2.5%BT, and 100mgCTXplus5%BT. Laminectomy was performed at the L3 level for all rats. The extent of epidural fibrosis was assessed 4 weeks later macroscopically and histopathologically. Hepatic and renal toxicity of study drugs was assessed histopathologically. RESULTS: Topical CTX and BT individually and in combination reduced epidural fibrosis after laminectomy in rats. Although a meaningful decrease of epidural fibrosis with individual application of CTX and BT (2.5% or 5%) was obtained (P < 0.05), the effect of their combination was more pronounced without meaningful hepatic and renal toxicity (P < 0.05). CONCLUSIONS: Combined use of topical CTX and BT could be a potential therapy for epidural fibrosis. Further research with this agents for the prevention of epidural fibrosis is warranted.


Assuntos
Alantoína/farmacologia , Benzotiazóis/farmacologia , Espaço Epidural/patologia , Heparina/farmacologia , Extratos Vegetais/farmacologia , Administração Tópica , Alantoína/administração & dosagem , Alantoína/toxicidade , Animais , Benzotiazóis/administração & dosagem , Benzotiazóis/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Modelos Animais de Doenças , Combinação de Medicamentos , Fibrose/tratamento farmacológico , Heparina/administração & dosagem , Heparina/toxicidade , Nefropatias/induzido quimicamente , Laminectomia/métodos , Masculino , Microscopia , Extratos Vegetais/administração & dosagem , Extratos Vegetais/toxicidade , Distribuição Aleatória , Ratos Wistar
6.
Nanotechnology ; 29(1): 015601, 2018 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-29130888

RESUMO

Polymeric biomaterials that can be smartly disassembled through the cleavage of the covalent bonds in a controllable way upon an environmental stimulus such as pH change, redox, special enzymes, temperature, or ultrasound, as well as light irradiation, but are otherwise stable under normal physiological conditions have attracted great attention in recent decades. The 2-(4-aminophenyl) benzothiazole molecule (CJM-126), as one of the benzothiazole derivatives, has exhibited a synergistic effect with cisplatin (CDDP) and restrains the bioactivities of a series of human breast cancer cell lines. In our study, novel NIR-responsive targeted binary-drug-loaded nanoparticles encapsulating indocyanine green (ICG) dye were prepared as a new co-delivery and combined therapeutic vehicle. The prepared drug-loaded polymeric nanoparticles (TNPs/CDDP-ICG) are stable under normal physiological conditions, while burst drugs release upon NIR laser irradiation in a mild acidic environment. The results further confirmed that the designed co-delivery platform showed higher cytotoxicity than the single free CDDP due to the synergistic treatment of CJM-126 and CDDP in vitro. Taken together, the work might provide a promising approach for effective site-specific antitumor therapy.


Assuntos
Antineoplásicos/administração & dosagem , Benzotiazóis/administração & dosagem , Cisplatino/administração & dosagem , Preparações de Ação Retardada/química , Nanopartículas/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Benzotiazóis/farmacocinética , Benzotiazóis/farmacologia , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Cisplatino/farmacocinética , Cisplatino/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Sinergismo Farmacológico , Feminino , Humanos , Hipertermia Induzida/métodos , Verde de Indocianina/administração & dosagem , Verde de Indocianina/farmacocinética , Verde de Indocianina/farmacologia , Raios Infravermelhos
7.
Vaccine ; 35(15): 1964-1971, 2017 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-28279563

RESUMO

Vaccine adjuvants are essential to drive a protective immune response in cases where vaccine antigens are weakly immunogenic, where vaccine antigen is limited, or where an increase in potency is needed for a specific population, such as the elderly. To discover novel vaccine adjuvants, we used a high-throughput screen (HTS) designed to identify small-molecule agonists of the RIG-I-like receptor (RLR) pathway leading to interferon regulatory factor 3 (IRF3) activation. RLRs are a group of cytosolic pattern-recognition receptors that are essential for the recognition of viral nucleic acids during infection. Upon binding of viral nucleic acid ligands, the RLRs become activated and signal to transcription factors, including IRF3, to initiate an innate immune transcriptional program to control virus infection. Among our HTS hits were a series of benzothiazole compounds from which we designed the lead analog, KIN1148. KIN1148 induced dose-dependent IRF3 nuclear translocation and specific activation of IRF3-responsive promoters. Prime-boost immunization of mice with a suboptimal dose of a monovalent pandemic influenza split virus H1N1 A/California/07/2009 vaccine plus KIN1148 protected against a lethal challenge with mouse-adapted influenza virus (A/California/04/2009) and induced an influenza virus-specific IL-10 and Th2 response by T cells derived from lung and lung-draining lymph nodes. Prime-boost immunization with vaccine plus KIN1148, but not prime immunization alone, induced antibodies capable of inhibiting influenza virus hemagglutinin and neutralizing viral infectivity. Nevertheless, a single immunization with vaccine plus KIN1148 provided increased protection over vaccine alone and reduced viral load in the lungs after challenge. These findings suggest that protection was at least partially mediated by a cellular immune component and that the induction of Th2 and immunoregulatory cytokines by a KIN1148-adjuvanted vaccine may be particularly beneficial for ameliorating the immunopathogenesis that is associated with influenza viruses.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Benzotiazóis/administração & dosagem , Proteína DEAD-box 58/metabolismo , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/imunologia , Fator Regulador 3 de Interferon/metabolismo , Adjuvantes Imunológicos/isolamento & purificação , Animais , Benzotiazóis/isolamento & purificação , Linhagem Celular , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Feminino , Ensaios de Triagem em Larga Escala , Humanos , Camundongos Endogâmicos C57BL , Infecções por Orthomyxoviridae/prevenção & controle , Receptores Imunológicos , Análise de Sobrevida
8.
Drug Test Anal ; 9(8): 1236-1242, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28039926

RESUMO

An ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for quantification of CM304, a novel and highly selective sigma-1 receptor antagonist that has recently entered into human clinical trials. A structural analogue of CM304, SN56, was used as the internal standard (IS). Chromatographic separation was achieved on an Acquity UPLC™ BEH C18 (1.7 µm, 2.1 mm × 50 mm) column using a mobile phase [water:methanol (0.1%v/v formic acid; 50:50, %v/v)] at a flow rate of 0.2 mL/min. Mass spectrometric detection was performed in the positive ionization mode with multiple reaction monitoring (MRM) using m/z transitions of 337 > 238 for CM304 and 319 > 220 for the IS. The method was found to be linear and reproducible with a regression coefficient consistently >0.99 for the calibration range of 3 to 3000 ng/mL. The extraction recovery ranged from 91.5 to 98.4% from spiked (7.5, 300 and 2526 ng/mL) plasma quality control samples. The precision (%RSD; 1.1 to 2.9%) and accuracy (%RE; -1.9 to 1.8%) were within acceptable limit. The validated method was successfully applied to a single dose oral and intravenous (I.V.) pharmacokinetic study of CM304 in rats. Following I.V. administration, the compound exhibited adequate exposure along with high extravascular distribution and insignificant amount of extra hepatic metabolism. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Azepinas/sangue , Benzotiazóis/sangue , Receptores sigma/antagonistas & inibidores , Espectrometria de Massas em Tandem/métodos , Administração Intravenosa , Administração Oral , Animais , Azepinas/administração & dosagem , Azepinas/análise , Benzotiazóis/administração & dosagem , Benzotiazóis/análise , Cromatografia Líquida de Alta Pressão/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Limite de Detecção , Masculino , Ratos , Ratos Sprague-Dawley , Receptor Sigma-1
9.
Neurosci Lett ; 624: 1-7, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27138280

RESUMO

Amyotrophic lateral sclerosis (ALS) is a progressive and fatal neurological disease characterized by degeneration and death of motor neurons. Aberrant protein aggregation and oxidative stress are implicated in the etiology of ALS; thus preventing propagation of early aggregation events and oxidative damage could be an effective therapy. We tested the effect of dietary supplementation (initiated 40 days of age) with 2-(2-hydroxyphenyl)-benzoxazole (HBX), a compound with metal chelator and anti-aggregation properties, on disease onset, progression and lifespan in the G93A mouse model of ALS. Tests were not sufficiently powerful to detect any change to survival distribution of mice treated with HBX. However, the disease onset was delayed and max lifespan was increased in the treatment group. Additionally, disease progression was moderated as shown by reduced neuromuscular denervation measured by repetitive nerve stimulation. F2-isoprostanes, a marker of oxidative damage, are elevated in skeletal muscle from G93A mice at onset and this increase is prevented in HBX fed G93A mice. Furthermore, HBX treatment reduced mutant SOD1 protein aggregation in whole spinal cord of G93A mice at disease onset. Overall, our data suggests that HBX may be able to improve the degenerative symptoms of ALS through the prevention of oxidative damage and protein aggregation. Further studies are needed to uncover the mechanistic effects of HBX in ameliorating ALS pathology.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/prevenção & controle , Benzotiazóis/administração & dosagem , Quelantes/administração & dosagem , Fenóis/administração & dosagem , Animais , Composição Corporal/efeitos dos fármacos , Cobre/metabolismo , Cistatinas/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Feminino , Ferro/metabolismo , Isoprostanos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Medula Espinal/metabolismo , Superóxido Dismutase-1/metabolismo , Análise de Sobrevida
10.
ScientificWorldJournal ; 2014: 194652, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25580452

RESUMO

Keeping in view the structural requirements suggested in the pharmacophore model for anticonvulsant activity, a new series of 3-(2-(substitutedbenzylidene)hydrazinyl)-N-(substituted benzo[d]thiazol-2-yl)-propanamides were synthesized with aromatic hydrophobic aryl ring (A), NH-C=O as hydrogen bonding domain (HBD), nitrogen atom as electron donor (D), and phenyl as distal aryl ring (C). Synthesized compounds were characterized by FTIR, (1)H NMR, (13)C NMR, mass spectroscopy, and elemental analysis. Preliminary in vivo anticonvulsant screening (phase I) was performed by two most adopted seizure models, maximal electroshock seizure (MES) and subcutaneous pentylenetetrazole (scPTZ). Based on anticonvulsant screening results, two compounds, 5h and 5p, were found to be most active; they exhibited activity comparable to standard drugs phenytoin (PHY) and carbamazepine (CBZ). These active compounds were subjected to phase II and phase III screening, where they displayed much higher protective index (PI) in comparison to the standard drugs. In phase IV screening, the bioavailability of active compounds was assessed on oral administration. Further, preliminary safety profiles of 5h and 5p were evaluated by the neurotoxicity testing and liver enzyme estimation.


Assuntos
Anticonvulsivantes/administração & dosagem , Benzotiazóis/administração & dosagem , Epilepsia/tratamento farmacológico , Convulsões/tratamento farmacológico , Animais , Anticonvulsivantes/efeitos adversos , Anticonvulsivantes/síntese química , Anticonvulsivantes/química , Benzotiazóis/efeitos adversos , Benzotiazóis/síntese química , Benzotiazóis/química , Sítios de Ligação , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Epilepsia/patologia , Ligação de Hidrogênio , Fenitoína/química , Convulsões/patologia , Relação Estrutura-Atividade
11.
Ross Fiziol Zh Im I M Sechenova ; 99(8): 901-16, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25470941

RESUMO

In the present work we investigated the effects of p53 inhibition by pifithrin-alpha (PFT) in vitro and in vivo on functioning vasopressinergic magnocellular neurones of rat hypothalamus. In vivo treatments with PFT were done by intra-hypothalamic microinjections or by intra peritoneal injections. In in vitro experiments hypothalamic slices containing supraoptic nuclei and intact pituitary were incubated with or without PFT. In all experiments we observed accumulation of vasopressin (VP) in the cell perikarya after PFT injections, however expression of VP mRNA was not changed. Analysis of VP content in the posterior pituitary demonstrated that amount of VP was significantly decreased after PFT treatments. Additionally, long-term inhibition of p53 in experiments with intra-hypothalamic injections of PFT resulted in an increased diuresis rate. The obtained results demonstrated that in all experiments PFT treatments inhibited VP anterograde transport from the cells of supraoptic nuclei. Moreover, analysis of MEK/ERK activities revealed that phosphorylation levels of MEK1/2 and ERK1/2 were decreased after PFT treatments. Our findings provide new evidences that p53 could be involved in the control of VP secretion from hypothalamo-hypophyseal system and that this action probably can be mediated by ERK signalling pathway.


Assuntos
Benzotiazóis/administração & dosagem , Neurônios/efeitos dos fármacos , Tolueno/análogos & derivados , Proteína Supressora de Tumor p53/metabolismo , Vasopressinas/metabolismo , Animais , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Ratos , Núcleo Supraóptico/efeitos dos fármacos , Núcleo Supraóptico/metabolismo , Tolueno/administração & dosagem , Proteína Supressora de Tumor p53/antagonistas & inibidores
12.
Int J Oncol ; 37(1): 21-30, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20514393

RESUMO

Ceramide signaling plays an important role in tumor progression and development of chemoresistance, and ceramide-based therapies are proposed as potential therapeutic tools for the treatment of breast cancer. We investigated the effect of exogenous ceramide on the cell cycle progression of MCF-7 breast cancer cells. Ceramide induced a selective arrest of MCF-7 cells in the G1-phase, which was associated with a decreased expression of cyclins D and E and increased expression of p53 and p21. Interestingly, inhibition of p53 using pifithrin alpha or RNAi sensitized MCF-7 cells to ceramide-induced cell death. DNA content analysis suggested that sensitization of cells was due to an increased induction of apoptosis in MCF-7 cells. The increased sensitivity to ceramide, in the context of p53 inhibition, may be due to decreased expression of p21, as siRNA targeted to p21 also sensitized MCF-7 cells to ceramide-induced death. These data demonstrate that in tumors with inactivating mutations of p53, ceramide-based therapies might provide a novel and effective treatment option.


Assuntos
Benzotiazóis/farmacologia , Neoplasias da Mama/patologia , Carcinoma/patologia , Ceramidas/farmacologia , RNA Interferente Pequeno/farmacologia , Tolueno/análogos & derivados , Proteína Supressora de Tumor p53/antagonistas & inibidores , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Benzotiazóis/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Carcinoma/tratamento farmacológico , Carcinoma/genética , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ceramidas/administração & dosagem , Ciclina D/genética , Ciclina E/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Avaliação Pré-Clínica de Medicamentos , Sinergismo Farmacológico , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , RNA Interferente Pequeno/administração & dosagem , Tolueno/administração & dosagem , Tolueno/farmacologia , Proteína Supressora de Tumor p53/genética
13.
J Control Release ; 141(2): 128-36, 2010 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-19748536

RESUMO

To provide a continuous and prolonged delivery of the substrate D-luciferin for bioluminescence imaging in vivo, luciferin was encapsulated into liposomes using either the pH gradient or acetate gradient method. Under optimum loading conditions, 0.17 mg luciferin was loaded per mg of lipid with 90-95% encapsulation efficiency, where active loading was 6 to 18-fold higher than that obtained with passive loading. Liposomal luciferin in a long-circulating formulation had good shelf stability, with 10% release over 3-month storage at 4 degrees C. Pharmacokinetic profiles of free and liposomal luciferin were then evaluated in transgenic mice expressing luciferase. In contrast to rapid in vivo clearance of free luciferin (t(1/2)=3.54 min), luciferin encapsulated into long-circulating liposomes showed a prolonged release over 24h. The first-order release rate constant of luciferin from long-circulating liposomes, as estimated from the best fit of the analytical model to the experimental data, was 0.01 h(-1). Insonation of luciferin-loaded temperature-sensitive liposomes directly injected into one tumor of Met1-luc tumor-bearing mice resulted in immediate emission of light. Systemic injection of luciferin-loaded long-circulating liposomes into Met1-luc tumor-bearing mice, followed by unilateral ultrasound-induced hyperthermia, produced a gradual increase in radiance over time, reaching a peak at 4-7 h post-ultrasound.


Assuntos
Benzotiazóis/administração & dosagem , Sistemas de Liberação de Medicamentos , Luminescência , Substâncias Luminescentes/administração & dosagem , Neoplasias Mamárias Experimentais/patologia , Animais , Benzotiazóis/química , Benzotiazóis/farmacocinética , Linhagem Celular Tumoral , Química Farmacêutica , Preparações de Ação Retardada , Composição de Medicamentos , Estabilidade de Medicamentos , Feminino , Concentração de Íons de Hidrogênio , Hipertermia Induzida , Injeções Intralesionais , Injeções Intravenosas , Lipossomos , Luciferases/genética , Luciferases/metabolismo , Substâncias Luminescentes/química , Substâncias Luminescentes/farmacocinética , Neoplasias Mamárias Experimentais/enzimologia , Neoplasias Mamárias Experimentais/genética , Camundongos , Camundongos Transgênicos , Modelos Biológicos , Permeabilidade , Solubilidade , Temperatura , Transfecção , Ultrassom
14.
Clin Interv Aging ; 4: 305-13, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19750232

RESUMO

Restless legs syndrome (RLS) is a condition characterized by discomfort at rest and urge to move focused on the legs. RLS may occur as an idiopathic, often hereditary condition (primary RLS), or in association with medical conditions (secondary RLS) including iron deficiency, uremia, and polyneuropathy. Current understanding of the pathophysiology of RLS points to the involvement of three interrelated components: dopaminergic dysfunction, impaired iron homeostasis, and genetic mechanisms. The diagnosis of RLS is made according to the consensus criteria by a National Institutes of Health panel: 1) an urge to move the legs, usually accompanied by uncomfortable sensations; 2) beginning or worsening during rest; 3) relieved by movement; and 4) worse, or only occurring, in the evening or at night. The differential diagnosis of RLS aims to: 1) distinguish RLS from other disorders with RLS-like symptoms and 2) identify secondary forms, with investigation of underlying diseases. The treatment of RLS demands a clinical evaluation to rule out and cure causes of secondary RLS, including iron supplementation when deficient, and to eliminate the triggering factors. The presence of neuropathy should be especially investigated in nonhereditary, late-onset RLS, in view of a possible treatment of the underlying disease. The first line treatment for idiopathic RLS is represented by dopamine agonists, in particular nonergot-derived ropinirole and pramipexole, whereas ergot dopamine agonists (cabergoline and pergolide) are no longer in first-line use given the risks of cardiac valvulopathy. Although no comparative trials have been published, a meta-analysis of pramipexole versus ropinirole suggests differences in efficacy and tolerability favoring pramipexole.


Assuntos
Benzotiazóis/uso terapêutico , Agonistas de Dopamina/uso terapêutico , Síndrome das Pernas Inquietas/tratamento farmacológico , Benzotiazóis/administração & dosagem , Benzotiazóis/farmacologia , Diagnóstico Diferencial , Agonistas de Dopamina/administração & dosagem , Agonistas de Dopamina/farmacologia , Humanos , Pramipexol , Síndrome das Pernas Inquietas/diagnóstico , Síndrome das Pernas Inquietas/fisiopatologia
15.
J Med Chem ; 52(1): 14-9, 2009 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-19072684

RESUMO

Current cancer chemotherapeutic agents clinically deployed today are designed to be indiscriminately cytotoxic, however, achieving selective targeting of cancer malignancies would allow for improved diagnostic and chemotherapeutic tools. Integrin alpha(4)beta(1), a heterodimeric cell surface receptor, is believed to have a low-affinity conformation in resting normal lymphocytes and an activated high-affinity conformation in cancerous cells, specifically T- and B-cell lymphomas. This highly attractive yet poorly understood receptor has been selectively targeted with the bisaryl urea peptidomimetic antagonist 1. However, concerns regarding its preliminary pharmacokinetic (PK) profile provided an impetus to change the pharmacophore from a bisaryl urea to a 2-arylaminobenzothiazole moiety, resulting in an analogue with improved physicochemical properties, solubility, and kidney:tumor ratio while maintaining potency (6; IC(50) = 53 pM). The results presented herein utilized heterocyclic and solid-phase chemistry, cell adhesion assay, and in vivo optical imaging using the cyanine dye Cy5.5 conjugate.


Assuntos
Benzotiazóis/química , Benzotiazóis/uso terapêutico , Integrina alfa4beta1/antagonistas & inibidores , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/patologia , Linfoma de Células T/tratamento farmacológico , Linfoma de Células T/patologia , Animais , Benzotiazóis/administração & dosagem , Benzotiazóis/síntese química , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Humanos , Concentração Inibidora 50 , Integrina alfa4beta1/metabolismo , Linfoma de Células B/metabolismo , Linfoma de Células T/metabolismo , Masculino , Camundongos , Camundongos Nus , Estrutura Molecular , Sesquiterpenos , Relação Estrutura-Atividade , Especificidade por Substrato , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Chem Biodivers ; 5(1): 140-52, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18205116

RESUMO

A series of carbamate derivatives of the H(3) antagonist ROS203 (1) were prepared, and their lipophilicity and steric hindrance were modulated by introducing linear or branched alkyl chains of various lengths. In vitro stability studies were conducted to evaluate how structural modulations affect the intrinsic reactivity of the carbamoyl moiety and its recognition by metabolic enzymes. Linear alkyl carbamates were the most susceptible to enzymatic hydrolysis, with bioconversion rates being higher in rat liver and plasma. Chain ramification significantly enhanced the enzymatic stability of the set, with two derivatives (1g and 1h) being more stable by a factor of 8-40 than the ethyl carbamate 1a. Incubation with bovine serum albumin (BSA) showed a protective role of proteins on chemical and porcine-liver esterase (PLE)-catalyzed hydrolysis. Ex vivo binding data after i.v. administration of 1h revealed prolonged displacement of the labeled ligand [(3)H]-(R)-alpha-methylhistamine ([(3)H]RAMHA) from rat-brain cortical membranes, when compared to 1. However, the high rates of bioconversion in liver, as well as the chemical instability of 1h, suggest that further work is needed to optimize the enzymatic and chemical stability of these compounds.


Assuntos
Benzotiazóis/síntese química , Benzotiazóis/farmacologia , Esterases/química , Antagonistas dos Receptores Histamínicos H3/síntese química , Antagonistas dos Receptores Histamínicos H3/farmacologia , Imidazóis/síntese química , Imidazóis/farmacologia , Receptores Histamínicos H3/efeitos dos fármacos , Soroalbumina Bovina/química , Animais , Benzotiazóis/administração & dosagem , Ácidos Carboxílicos/química , Catálise , Bovinos , Avaliação Pré-Clínica de Medicamentos , Estabilidade de Medicamentos , Antagonistas dos Receptores Histamínicos H3/administração & dosagem , Concentração de Íons de Hidrogênio , Hidrólise , Imidazóis/administração & dosagem , Imidazóis/química , Injeções Intravenosas , Fígado/enzimologia , Fígado/metabolismo , Estrutura Molecular , Ratos , Estereoisomerismo , Relação Estrutura-Atividade , Suínos
17.
J Pharmacol Exp Ther ; 323(1): 128-37, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17652633

RESUMO

Capsaicin, the active ingredient in some pain-relieving creams, is an agonist of a nonselective cation channel known as the transient receptor potential vanilloid type 1 (TRPV1). The pain-relieving mechanism of capsaicin includes desensitization of the channel, suggesting that TRPV1 antagonism may be a viable pain therapy approach. In agreement with the above notion, several TRPV1 antagonists have been reported to act as antihyperalgesics. Here, we report the in vitro and in vivo characterization of a novel and selective TRPV1 antagonist, N-(4-[6-(4-trifluoromethyl-phenyl)-pyrimidin-4-yloxy]-benzothiazol-2-yl)-acetamide I (AMG 517), and compare its pharmacology with that of a closely related analog, tert-butyl-2-(6-([2-(acetylamino)-1,3-benzothiazol-4-yl]oxy)pyrimidin-4-yl)-5-(trifluoromethyl)phenylcarbamate (AMG8163). Both AMG 517 and AMG8163 potently and completely antagonized capsaicin, proton, and heat activation of TRPV1 in vitro and blocked capsaicin-induced flinch in rats in vivo. To support initial clinical investigations, AMG 517 was evaluated in a comprehensive panel of toxicology studies that included in vivo assessments in rodents, dogs, and monkeys. The toxicology studies indicated that AMG 517 was generally well tolerated; however, transient increases in body temperature (hyperthermia) were observed in all species after AMG 517 dosing. To further investigate this effect, we tested and showed that the antipyretic, acetaminophen, suppressed the hyperthermia caused by TRPV1 blockade. We also showed that repeated administration of TRPV1 antagonists attenuated the hyperthermia response, whereas the efficacy in capsaicin-induced flinch model was maintained. In conclusion, these studies suggest that the transient hyperthermia elicited by TRPV1 blockade may be manageable in the development of TRPV1 antagonists as therapeutic agents. However, the impact of TRPV1 antagonist-induced hyperthermia on their clinical utility is still unknown.


Assuntos
Analgésicos não Narcóticos/uso terapêutico , Benzotiazóis/uso terapêutico , Febre/tratamento farmacológico , Dor/tratamento farmacológico , Pirimidinas/uso terapêutico , Canais de Cátion TRPV/antagonistas & inibidores , Analgésicos não Narcóticos/administração & dosagem , Analgésicos não Narcóticos/química , Analgésicos não Narcóticos/farmacologia , Animais , Benzotiazóis/administração & dosagem , Benzotiazóis/química , Benzotiazóis/farmacologia , Temperatura Corporal/efeitos dos fármacos , Células CHO , Capsaicina/farmacologia , Cricetinae , Cricetulus , Modelos Animais de Doenças , Esquema de Medicação , Desenho de Fármacos , Feminino , Febre/metabolismo , Adjuvante de Freund/farmacologia , Macaca fascicularis , Masculino , Estrutura Molecular , Dor/metabolismo , Pirimidinas/administração & dosagem , Pirimidinas/química , Pirimidinas/farmacologia , Ratos , Ratos Sprague-Dawley , Telemetria
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