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1.
Eur J Cancer ; 126: 93-103, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31927215

RESUMO

INTRODUCTION: Uveal melanoma (UM) is a rare and malignant intraocular tumour with a dismal prognosis. Despite a good control of the primary tumour by radiation or surgery, up to 50% of patients subsequently develop metastasis for which no efficient treatment is yet available. METHODOLOGY: To identify therapeutic opportunities, we performed an in vitro screen of 30 combinations of different inhibitors of pathways that are dysregulated in UM. Effects of drug combinations on viability, cell cycle and apoptosis were assessed in eight UM cell lines. The best synergistic combinations were further evaluated in six UM patient-derived xenografts (PDXs). RESULTS: We demonstrated that the Bcl-2/XL/W inhibitor (ABT263) sensitised the UM cell lines to other inhibitors, mainly to mammalian target of rapamycin (mTOR), mitogen-activated protein kinase kinase (MEK) and murine double minute 2 (MDM2) inhibitors. mTOR (RAD001) and MEK1/2 (trametinib) inhibitors were efficient as single agents, but their combinations with ABT263 displayed no synergism in UM PDXs. In contrast, the combination of ABT263 with MDM2 inhibitor (HDM201) showed a trend for a synergistic effect. CONCLUSION: We showed that inhibition of Bcl-2/XL/W sensitised the UM cell lines to other treatments encouraging investigation of the underlying mechanisms. Furthermore, our findings highlighted Bcl-2/XL/W and MDM2 co-inhibition as a promising strategy in UM.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Melanoma/tratamento farmacológico , Neoplasias Uveais/tratamento farmacológico , Compostos de Anilina/administração & dosagem , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/antagonistas & inibidores , Proteínas Reguladoras de Apoptose/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Combinação de Medicamentos , Everolimo/administração & dosagem , Humanos , Imidazóis/administração & dosagem , Melanoma/metabolismo , Melanoma/patologia , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Piridonas/administração & dosagem , Pirimidinas/administração & dosagem , Pirimidinonas/administração & dosagem , Pirróis/administração & dosagem , Sulfonamidas/administração & dosagem , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo , Neoplasias Uveais/metabolismo , Neoplasias Uveais/patologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Proteína bcl-X/antagonistas & inibidores , Proteína bcl-X/metabolismo
2.
Eur J Cancer ; 123: 58-71, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31670077

RESUMO

BACKGROUND: Although a myriad of novel treatments entered the treatment paradigm for advanced melanoma, there is lack of head-to-head evidence. We conducted a network meta-analysis (NMA) to estimate each treatment's relative effectiveness and safety. METHODS: A systematic literature review (SLR) was conducted in Embase, MEDLINE and Cochrane to identify all phase III randomised controlled trials (RCTs) with a time frame from January 1, 2010 to March 11, 2019. We retrieved evidence on treatment-related grade III/IV adverse events, progression-free survival (PFS) and overall survival (OS). Evidence was synthesised using a Bayesian fixed-effect NMA. Reference treatment was dacarbazine. In accordance with RCTs, dacarbazine was pooled with temozolomide, paclitaxel and paclitaxel plus carboplatin. To increase homogeneity of the study populations, RCTs were only included if patients were not previously treated with novel treatments. RESULTS: The SLR identified 28 phase III RCTs involving 14,376 patients. Nineteen and seventeen treatments were included in the effectiveness and safety NMA, respectively. For PFS, dabrafenib plus trametinib (hazard ratio [HR] PFS: 0.21) and vemurafenib plus cobimetinib (HR PFS: 0.22) were identified as most favourable treatments. Both had, however, less favourable safety profiles. Five other treatments closely followed (dabrafenib [HR PFS: 0.30], nivolumab plus ipilimumab [HR PFS: 0.34], vemurafenib [HR PFS: 0.38], nivolumab [HR PFS: 0.42] and pembrolizumab [HR PFS: 0.46]). In contrast, for OS, nivolumab plus ipilimumab (HR OS: 0.39), nivolumab (HR OS: 0.46) and pembrolizumab (HR OS: 0.50) were more favourable than dabrafenib plus trametinib (HR OS: 0.55) and vemurafenib plus cobimetinib (HR OS: 0.57). CONCLUSIONS: Our NMA identified the most effective treatment options for advanced melanoma and provided valuable insights into each novel treatment's relative effectiveness and safety. This information may facilitate evidence-based decision-making and may support the optimisation of treatment and outcomes in everyday clinical practice.


Assuntos
Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Vacinas Anticâncer/uso terapêutico , Melanoma/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/uso terapêutico , Azetidinas/administração & dosagem , Azetidinas/uso terapêutico , Benzimidazóis/administração & dosagem , Benzimidazóis/uso terapêutico , Carboplatina/administração & dosagem , Carboplatina/uso terapêutico , Dacarbazina/administração & dosagem , Dacarbazina/uso terapêutico , Humanos , Hidrazinas/administração & dosagem , Hidrazinas/uso terapêutico , Imidazóis/administração & dosagem , Imidazóis/uso terapêutico , Interleucina-2/administração & dosagem , Interleucina-2/uso terapêutico , Ipilimumab/administração & dosagem , Ipilimumab/uso terapêutico , Lenalidomida/administração & dosagem , Lenalidomida/uso terapêutico , Melanoma/imunologia , Melanoma/patologia , Metanálise em Rede , Compostos de Nitrosoureia/administração & dosagem , Compostos de Nitrosoureia/uso terapêutico , Nivolumabe/administração & dosagem , Nivolumabe/uso terapêutico , Compostos Organofosforados/administração & dosagem , Compostos Organofosforados/uso terapêutico , Oximas/administração & dosagem , Oximas/uso terapêutico , Paclitaxel/administração & dosagem , Paclitaxel/uso terapêutico , Piperidinas/administração & dosagem , Piperidinas/uso terapêutico , Intervalo Livre de Progressão , Modelos de Riscos Proporcionais , Piridonas/administração & dosagem , Piridonas/uso terapêutico , Pirimidinonas/administração & dosagem , Pirimidinonas/uso terapêutico , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologia , Sorafenibe/administração & dosagem , Sorafenibe/uso terapêutico , Taxa de Sobrevida , Temozolomida/administração & dosagem , Temozolomida/uso terapêutico , Resultado do Tratamento
3.
J Med Chem ; 61(17): 7671-7686, 2018 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-30106292

RESUMO

We previously reported Chalcone-4 (1) that binds the chemokine CXCL12, not its cognate receptors CXCR4 or CXCR7, and neutralizes its biological activity. However, this neutraligand suffers from limitations such as poor chemical stability, solubility, and oral activity. Herein, we report on the discovery of pyrimidinone 57 (LIT-927), a novel neutraligand of CXCL12 which displays a higher solubility than 1 and is no longer a Michael acceptor. While both 1 and 57 reduce eosinophil recruitment in a murine model of allergic airway hypereosinophilia, 57 is the only one to display inhibitory activity following oral administration. Thereby, we here describe 57 as the first orally active CXCL12 neutraligand with anti-inflammatory properties. Combined with a high binding selectivity for CXCL12 over other chemokines, 57 represents a powerful pharmacological tool to investigate CXCL12 physiology in vivo and to explore the activity of chemokine neutralization in inflammatory and related diseases.


Assuntos
Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Quimiocina CXCL12/metabolismo , Síndrome Hipereosinofílica/tratamento farmacológico , Pirimidinonas/química , Pirimidinonas/farmacologia , Administração Oral , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/farmacocinética , Quimiocina CXCL12/química , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Transferência Ressonante de Energia de Fluorescência , Humanos , Hipersensibilidade/tratamento farmacológico , Hipersensibilidade/etiologia , Masculino , Camundongos Endogâmicos BALB C , Modelos Moleculares , Pirimidinonas/administração & dosagem , Pirimidinonas/metabolismo , Pirimidinonas/farmacocinética , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Relação Estrutura-Atividade
4.
ACS Nano ; 12(3): 2695-2707, 2018 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-29518321

RESUMO

The treatment of melanoma requires complete removal of tumor cells and simultaneous tissue regeneration of tumor-initiated cutaneous defects. Herein, copper silicate hollow microspheres (CSO HMSs)-incorporated bioactive scaffolds were designed for chemo-photothermal therapy of skin cancers and regeneration of skin tissue. CSO HMSs were synthesized with interior hollow and external nanoneedle microstructure, showing excellent drug-loading capacity and photothermal effects. With incorporation of drug-loaded CSO HMSs into the electrospun scaffolds, the composite scaffolds exhibited excellent photothermal effects and controlled NIR-triggered drug release, leading to distinctly synergistic chemo-photothermal therapy of skin cancer both in vitro and in vivo. Furthermore, such CSO HMSs-incorporated scaffolds could promote proliferation and attachment of normal skin cells and accelerate skin tissue healing in tumor-bearing and diabetic mice. Taken together, CSO HMSs-incorporated scaffolds may be used for complete eradication of the remaining tumor cells after surgery and simultaneous tissue healing, which offers an effective strategy for therapy and regeneration of tumor-initiated tissue defects.


Assuntos
Antineoplásicos/uso terapêutico , Cobre/uso terapêutico , Melanoma/terapia , Nanoestruturas/uso terapêutico , Piridonas/uso terapêutico , Pirimidinonas/uso terapêutico , Silicatos/uso terapêutico , Neoplasias Cutâneas/terapia , Animais , Antineoplásicos/administração & dosagem , Linhagem Celular Tumoral , Cobre/química , Portadores de Fármacos/química , Portadores de Fármacos/uso terapêutico , Sistemas de Liberação de Medicamentos , Hipertermia Induzida/métodos , Masculino , Melanoma/patologia , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanoestruturas/química , Fototerapia/métodos , Piridonas/administração & dosagem , Pirimidinonas/administração & dosagem , Silicatos/química , Neoplasias Cutâneas/patologia , Alicerces Teciduais/química
5.
Clin Cancer Res ; 23(15): 4027-4034, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28377484

RESUMO

Purpose: Pazopanib, a multireceptor tyrosine kinase inhibitor targeting primarily VEGFRs1-3, is approved for advanced soft tissue sarcoma (STS) and renal cell cancer. Downstream of VEGFR, trametinib is an FDA-approved MEK inhibitor used for melanoma. We hypothesized that vertical pathway inhibition using trametinib would synergize with pazopanib in advanced STS.Experimental Design: In an open-label, multicenter, investigator-initiated National Comprehensive Cancer Network (NCCN)-sponsored trial, patients with metastatic or advanced STS received pazopanib 800 mg and 2 mg of trametinib continuously for 28-day cycles. The primary endpoint was 4-month progression-free survival (PFS). Secondary endpoints were overall survival, response rate, and disease control rate.Results: Twenty-five patients were enrolled. The median age was 49 years (range, 22-77 years) and 52% were male. Median PFS was 2.27 months [95% confidence interval (CI), 1.9-3.9], and the 4-month PFS rate was 21.1% (95% CI, 9.7-45.9), which was not an improvement over the hypothesized null 4-month PFS rate of 28.3% (P = 0.79). Median overall survival was 9.0 months (95% CI, 5.7-17.7). A partial response occurred in 2 (8%) of the evaluable patients (95% CI, 1.0-26.0), one with PIK3CA E542K-mutant embryonal rhabdomyosarcoma and another with spindle cell sarcoma. The disease control rate was 14/25 (56%; 95% CI, 34.9-75.6). The most common adverse events were diarrhea (84%), nausea (64%), fatigue (56%), and hypertension (52%).Conclusions: The combination of pazopanib and trametinib was tolerable without indication of added activity of the combination in STS. Further study may be warranted in RAS/RAF aberrant sarcomas. Clin Cancer Res; 23(15); 4027-34. ©2017 AACR.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Piridonas/administração & dosagem , Pirimidinas/administração & dosagem , Pirimidinonas/administração & dosagem , Sarcoma/tratamento farmacológico , Sulfonamidas/administração & dosagem , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Intervalo Livre de Doença , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Humanos , Indazóis , MAP Quinase Quinase Quinase 1/antagonistas & inibidores , Masculino , Pessoa de Meia-Idade , Inibidores de Proteínas Quinases/administração & dosagem , Piridonas/efeitos adversos , Pirimidinas/efeitos adversos , Pirimidinonas/efeitos adversos , Sarcoma/genética , Sarcoma/patologia , Sulfonamidas/efeitos adversos , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores
6.
Science ; 345(6197): 688-93, 2014 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-25104390

RESUMO

Spinal muscular atrophy (SMA) is a genetic disease caused by mutation or deletion of the survival of motor neuron 1 (SMN1) gene. A paralogous gene in humans, SMN2, produces low, insufficient levels of functional SMN protein due to alternative splicing that truncates the transcript. The decreased levels of SMN protein lead to progressive neuromuscular degeneration and high rates of mortality. Through chemical screening and optimization, we identified orally available small molecules that shift the balance of SMN2 splicing toward the production of full-length SMN2 messenger RNA with high selectivity. Administration of these compounds to Δ7 mice, a model of severe SMA, led to an increase in SMN protein levels, improvement of motor function, and protection of the neuromuscular circuit. These compounds also extended the life span of the mice. Selective SMN2 splicing modifiers may have therapeutic potential for patients with SMA.


Assuntos
Processamento Alternativo/efeitos dos fármacos , Cumarínicos/administração & dosagem , Isocumarinas/administração & dosagem , Longevidade/efeitos dos fármacos , Atrofia Muscular Espinal/tratamento farmacológico , Pirimidinonas/administração & dosagem , Bibliotecas de Moléculas Pequenas/administração & dosagem , Proteína 2 de Sobrevivência do Neurônio Motor/genética , Administração Oral , Animais , Células Cultivadas , Cumarínicos/química , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Humanos , Isocumarinas/química , Camundongos , Atrofia Muscular Espinal/genética , Atrofia Muscular Espinal/metabolismo , Pirimidinonas/química , RNA Mensageiro/genética , Deleção de Sequência , Bibliotecas de Moléculas Pequenas/química , Proteína 2 de Sobrevivência do Neurônio Motor/metabolismo
7.
PLoS One ; 8(7): e67583, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23844038

RESUMO

Mitogen-Activated Protein Kinase (MAPK) pathway activation has been implicated in many types of human cancer. BRAF mutations that constitutively activate MAPK signalling and bypass the need for upstream stimuli occur with high prevalence in melanoma, colorectal carcinoma, ovarian cancer, papillary thyroid carcinoma, and cholangiocarcinoma. In this report we characterize the novel, potent, and selective BRAF inhibitor, dabrafenib (GSK2118436). Cellular inhibition of BRAF(V600E) kinase activity by dabrafenib resulted in decreased MEK and ERK phosphorylation and inhibition of cell proliferation through an initial G1 cell cycle arrest, followed by cell death. In a BRAF(V600E)-containing xenograft model of human melanoma, orally administered dabrafenib inhibited ERK activation, downregulated Ki67, and upregulated p27, leading to tumor growth inhibition. However, as reported for other BRAF inhibitors, dabrafenib also induced MAPK pathway activation in wild-type BRAF cells through CRAF (RAF1) signalling, potentially explaining the squamous cell carcinomas and keratoacanthomas arising in patients treated with BRAF inhibitors. In addressing this issue, we showed that concomitant administration of BRAF and MEK inhibitors abrogated paradoxical BRAF inhibitor-induced MAPK signalling in cells, reduced the occurrence of skin lesions in rats, and enhanced the inhibition of human tumor xenograft growth in mouse models. Taken together, our findings offer preclinical proof of concept for dabrafenib as a specific and highly efficacious BRAF inhibitor and provide evidence for its potential clinical benefits when used in combination with a MEK inhibitor.


Assuntos
Melanoma/tratamento farmacológico , Melanoma/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas B-raf/metabolismo , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linhagem Celular Tumoral , Avaliação Pré-Clínica de Medicamentos , Ativação Enzimática/efeitos dos fármacos , Feminino , Humanos , Imidazóis/administração & dosagem , Melanoma/patologia , Camundongos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Mutação , Oximas/administração & dosagem , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/genética , Piridonas/administração & dosagem , Pirimidinonas/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
8.
J Dairy Sci ; 96(2): 1000-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23245959

RESUMO

Staphylococcus aureus is a leading cause of intramammary infections (IMI). We recently demonstrated that Staph. aureus strains express the gene guaA during bovine IMI. This gene codes for a guanosine monophosphate synthetase and its expression is regulated by a guanine riboswitch. The guanine analog 2,5,6-triaminopyrimidine-4-one (PC1) is a ligand of the guanine riboswitch. Interactions between PC1 and its target result in inhibition of guanosine monophosphate synthesis and subsequent death of the bacterium. The present study describes the investigational use of PC1 for therapy of Staph. aureus IMI in lactating cows. The in vitro minimal inhibitory concentration of PC1 ranged from 0.5 to 4 µg/mL for a variety of Staph. aureus and Staphylococcus epidermidis strains and required a reducing agent for stability and full potency. A safety assessment study was performed, whereby the healthy quarters of 4 cows were infused with increasing doses of PC1 (0, 150, 250, and 500 mg). Over the 44 h following infusions, no obvious adverse effect was observed. Ten Holstein multiparous cows in mid lactation were then experimentally infused into 3 of the quarters with approximately 50 cfu of Staph. aureus strain SHY97-3906 and infection was allowed to progress for 2 wk before starting PC1 treatment. Bacterial counts reached then about 10(3) to 10(4) cfu/mL of milk. Infected quarters were treated with 1 of 3 doses of PC1 (0, 250, or 500 mg) after each morning and evening milking for 7d (i.e., 14 intramammary infusions of PC1). During the treatment period, milk from PC1-treated quarters showed a significant reduction in bacterial concentrations. However, this reduction of Staph. aureus count in milk was not maintained during the 4 wk following the end of the treatment and only 15% of the PC1-treated quarters underwent bacteriological cure. The somatic cell count and the quarter milk production were not affected by treatments. Although bacterial clearance was not achieved following treatment with PC1, these results demonstrate that the Staph. aureus guanine riboswitch represents a relevant and promising drug target for a novel class of antibiotics for the animal food industry.


Assuntos
Antibacterianos/uso terapêutico , Mastite Bovina/tratamento farmacológico , Pirimidinonas/uso terapêutico , Riboswitch/efeitos dos fármacos , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/efeitos dos fármacos , Animais , Antibacterianos/administração & dosagem , Bovinos , Relação Dose-Resposta a Droga , Feminino , Guanina , Ligantes , Mastite Bovina/microbiologia , Testes de Sensibilidade Microbiana , Pirimidinonas/administração & dosagem , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/genética
9.
Asian J Androl ; 13(5): 742-6, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21478894

RESUMO

In this study, we investigated the effects of a combination of Ginkgo biloba extracts (GBE) and phosphodiesterase type 5 (PDE-5) inhibitors on the muscular tone of the corpus cavernosum and potassium channel activity of corporal smooth muscle cells. Strips of corpus cavernosum from male New Zealand white rabbits were mounted in organ baths for isometric tension studies. After contraction with 1×10⁻5 mol l⁻¹ norepinephrine, GBE (0.01-1 mg ml⁻¹) and mirodenafil (0.01-100 nmol l⁻¹) were added together into the organ bath. In electrophysiological studies, whole-cell currents were recorded by the conventional patch-clamp technique in cultured smooth muscle cells of the human corpus cavernosum. The corpus cavernosum was relaxed in response to GBE in a dose-dependent manner (from 0.64%±8.35% at 0.01 mg ml⁻¹ to 52.28% ± 11.42% at 1 mg ml⁻¹). After pre-treatment with 0.03 mg ml⁻¹ of GBE, the relaxant effects of mirodenafil were increased at all concentrations. After tetraethylammonium (TEA) (1 mmol l⁻¹) administration, the increased effects were inhibited (P<0.01). Extracellular administration of GBE increased the whole-cell K(+) outward currents in a dose-dependent fashion. The increase of the outward current was inhibited by 1 mmol l⁻¹ TEA. These results suggest that GBE could increase the relaxant potency of mirodenafil even at a minimally effective dose. The K(+) flow through potassium channels might be one of the mechanisms involved in this synergistic relaxation.


Assuntos
Ginkgo biloba/química , Músculo Liso Vascular/efeitos dos fármacos , Pênis/efeitos dos fármacos , Inibidores da Fosfodiesterase 5/farmacologia , Extratos Vegetais/farmacologia , Canais de Potássio/efeitos dos fármacos , Pirimidinonas/farmacologia , Sulfonamidas/farmacologia , Animais , Masculino , Relaxamento Muscular/efeitos dos fármacos , Técnicas de Patch-Clamp , Pênis/fisiopatologia , Inibidores da Fosfodiesterase 5/administração & dosagem , Extratos Vegetais/administração & dosagem , Pirimidinonas/administração & dosagem , Coelhos , Sulfonamidas/administração & dosagem
10.
Pharmacotherapy ; 30(8): 797-805, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20653355

RESUMO

STUDY OBJECTIVE: . To determine the influence of Echinacea purpurea on the pharmacokinetics of lopinavir-ritonavir and on cytochrome P450 (CYP) 3A and P-glycoprotein activity by using the probe substrates midazolam and fexofenadine, respectively. DESIGN: Open-label, single-sequence pharmacokinetic study. SETTING: Outpatient clinic in a federal government research center. SUBJECTS: Thirteen healthy volunteers (eight men, five women). INTERVENTION: Subjects received lopinavir 400 mg-ritonavir 100 mg twice/day with meals for 29.5 days. On day 16, subjects received E. purpurea 500 mg 3 times/day for 28 days: 14 days in combination with lopinavir-ritonavir and 14 days of E. purpurea alone. In order to assess CYP3A and P-glycoprotein activity, subjects received single oral doses of midazolam 8 mg and fexofenadine 120 mg, respectively, before and after the 28 days of E. purpurea. MEASUREMENTS AND MAIN RESULTS: On days 15 and 30 of lopinavir-ritonavir administration (before and after E. purpurea administration, respectively), serial blood samples were collected over 12 hours to determine lopinavir and ritonavir concentrations and subsequent pharmacokinetic parameters by using noncompartmental methods. Neither lopinavir nor ritonavir pharmacokinetics were significantly altered by 14 days of E. purpurea coadministration. The post-echinacea: pre-echinacea geometric mean ratios (GMRs) for lopinavir area under the concentration-time curve (AUC) from 0-12 hours and for maximum concentration were 0.96 (90% confidence interval [CI] 0.83-1.10, p=0.82) and 1.00 (90% CI 0.88-1.12, p=0.72), respectively. Conversely, GMRs for midazolam AUC from time zero extrapolated to infinity and oral clearance were 0.73 (90% CI 0.61-0.85, p=0.008) and 1.37 (90% CI 1.10-1.63, p=0.02), respectively. Fexofenadine pharmacokinetics did not significantly differ before and after E. purpurea administration (p>0.05). CONCLUSION: Echinacea purpurea induced CYP3A activity but did not alter lopinavir concentrations, most likely due to the presence of the potent CYP3A inhibitor, ritonavir. Echinacea purpurea is unlikely to alter the pharmacokinetics of ritonavir-boosted protease inhibitors but may cause modest decreases in plasma concentrations of other CYP3A substrates.


Assuntos
Citocromo P-450 CYP3A/biossíntese , Echinacea , Interações Ervas-Drogas , Pirimidinonas/administração & dosagem , Ritonavir/administração & dosagem , Adulto , Citocromo P-450 CYP3A/metabolismo , Combinação de Medicamentos , Indução Enzimática/efeitos dos fármacos , Indução Enzimática/fisiologia , Feminino , Interações Ervas-Drogas/fisiologia , Humanos , Lopinavir , Masculino , Pessoa de Meia-Idade , Extratos Vegetais/administração & dosagem , Adulto Jovem
12.
Blood ; 114(8): 1563-75, 2009 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-19541822

RESUMO

Chronic lymphocytic leukemia (CLL) is an incurable disease derived from the monoclonal expansion of CD5(+) B lymphocytes. High expression levels of ZAP-70 or CD38 and deletions of 17p13 (TP53) and 11q22-q23 (ATM) are associated with poorer overall survival and shorter time to disease progression. DNA damage and p53 play a pivotal role in apoptosis induction in response to conventional chemotherapy, because deletions of ATM or p53 identify CLL patients with resistance to treatment. Forodesine is a transition-state inhibitor of the purine nucleoside phosphorylase with antileukemic activity. We show that forodesine is highly cytotoxic as single agent or in combination with bendamustine and rituximab in primary leukemic cells from CLL patients regardless of CD38/ZAP-70 expression and p53 or ATM deletion. Forodesine activates the mitochondrial apoptotic pathway by decreasing the levels of antiapoptotic MCL-1 protein and induction of proapoptotic BIM protein. Forodesine induces transcriptional up-regulation of p73, a p53-related protein able to overcome the resistance to apoptosis of CLL cells lacking functional p53. Remarkably, no differences in these apoptotic markers were observed based on p53 or ATM status. In conclusion, forodesine induces apoptosis of CLL cells bypassing the DNA-damage/ATM/p53 pathway and might represent a novel chemotherapeutic approach that deserves clinical investigation.


Assuntos
Proteínas Reguladoras de Apoptose/genética , Apoptose/efeitos dos fármacos , Proteínas de Ligação a DNA/genética , Leucemia Linfocítica Crônica de Células B/patologia , Proteínas de Membrana/genética , Proteínas Nucleares/genética , Proteínas Proto-Oncogênicas/genética , Nucleosídeos de Purina/farmacologia , Pirimidinonas/farmacologia , Proteína Supressora de Tumor p53/fisiologia , Proteínas Supressoras de Tumor/genética , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Murinos , Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/fisiologia , Proteínas Reguladoras de Apoptose/metabolismo , Proteína 11 Semelhante a Bcl-2 , Cloridrato de Bendamustina , Ciclofosfamida/administração & dosagem , Proteínas de Ligação a DNA/metabolismo , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/genética , Proteínas de Membrana/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/fisiologia , Compostos de Mostarda Nitrogenada/administração & dosagem , Proteínas Nucleares/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Nucleosídeos de Purina/administração & dosagem , Nucleosídeos de Purina/uso terapêutico , Pirimidinonas/administração & dosagem , Pirimidinonas/uso terapêutico , Rituximab , Células Tumorais Cultivadas , Proteína Tumoral p73 , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Vidarabina/administração & dosagem , Vidarabina/análogos & derivados
13.
J Pharmacol Exp Ther ; 329(2): 429-38, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19182070

RESUMO

The mammalian neuropeptide, melanin-concentrating hormone, interacts with two G protein-coupled receptors, melanin-concentrating hormone receptor (MCHR) 1 and MCHR2; however, only MCHR1 is expressed in rats and mice. In the present study, we evaluated MCHR1 antagonism in preclinical models believed to be predictive of antiobesity and antidepressant activity. Central activity of the selective MCHR1 antagonist, GW803430 [6-(4-chloro-phenyl)-3-[3-methoxy-4-(2-pyrrolidin-1-yl-ethoxy)-phenyl]-3H-thieno[3,2-d]pyrimidin-4-one], was evaluated using ex vivo binding with autoradiography. Effective doses of GW803430 (1 and 3 mg/kg p.o.) were correlated with antiobesity activity in a 14-day study of diet-induced obese rats. GW803430 was evaluated subsequently for antidepressant-like effects in mice and rats. Acute and subchronic administration reduced immobility time in the mouse forced-swim test at doses of 3 (acute) and 3 and 10 (chronic) mg/kg p.o., an effect that was absent in MCHR1(-/-) mice. Combined subeffective doses of GW803430 (0.3 and 1 mg/kg p.o.) and imipramine (5 mg/kg) produced a robust antidepressant-like response. The compound was also active in the tail suspension test at a dose of 10 mg/kg p.o. GW803430 (30 mg/kg p.o.) significantly reduced submissive behaviors at weeks 2 and 3, a model of submissive behavior that may predict antidepressant onset. GW803430 decreased marble burying in mice at doses of 3, 10, and 30 mg/kg p.o., an assay that detects anxiolytic-like effects. Thus, GW803430 produces robust antiobesity and antidepressant-like effects in rats and mice at doses that compete for central MCHR1 in vivo. As such, MCHR1 should be considered as a promising target for future drug discovery efforts.


Assuntos
Fármacos Antiobesidade/uso terapêutico , Antidepressivos/uso terapêutico , Depressão/tratamento farmacológico , Obesidade/tratamento farmacológico , Pirimidinonas/uso terapêutico , Receptores de Somatostatina/antagonistas & inibidores , Tiofenos/uso terapêutico , Animais , Fármacos Antiobesidade/administração & dosagem , Fármacos Antiobesidade/farmacologia , Antidepressivos/administração & dosagem , Antidepressivos/farmacologia , Autorradiografia , Comportamento Animal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Depressão/metabolismo , Depressão/fisiopatologia , Depressão/psicologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Masculino , Camundongos , Camundongos Knockout , Atividade Motora/efeitos dos fármacos , Obesidade/metabolismo , Obesidade/fisiopatologia , Obesidade/psicologia , Ligação Proteica , Pirimidinonas/administração & dosagem , Pirimidinonas/farmacologia , Ratos , Ratos Long-Evans , Ratos Sprague-Dawley , Receptores de Somatostatina/genética , Predomínio Social , Natação , Tiofenos/administração & dosagem , Tiofenos/farmacologia
14.
Antimicrob Agents Chemother ; 52(7): 2521-8, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18474576

RESUMO

Telbivudine is a novel nucleoside drug recently approved for the treatment of patients with chronic hepatitis B. Its nonclinical safety was evaluated in a comprehensive program of studies, including safety pharmacology, acute and chronic toxicity, reproductive and developmental toxicity, genotoxicity, and carcinogenicity. There were no test article-related effects observed in an in vitro hERG assay or in a core battery of safety pharmacology studies (central nervous system, respiratory, and cardiovascular safety pharmacology studies). Telbivudine was well tolerated in rats and in monkeys following single oral doses up to 2,000 mg/kg/day. Except for equivocal axonopathic findings in monkeys and occasional incidences of emesis, soft feces, and minor changes in body weight and food consumption, there was no target organ toxicity observed in mice, rats, or monkeys following oral administration for up to 3, 6, or 9 months, respectively, at doses up to 3,000 mg/kg/day. Axonopathy in the sciatic nerves and in the spinal cords of monkeys dosed at 1,000 mg/kg/day observed in a 9-month study was considered equivocal, as the role of telbivudine in the injury could not be determined. Slightly higher incidences of abortion and premature delivery observed in rabbits dosed at 1,000 mg/kg/day were considered secondary to maternal toxicity. There was no evidence of genotoxicity or carcinogenicity. These results suggest that telbivudine has a favorable safety profile and support its use in patients with chronic compensated hepatitis B viral infection.


Assuntos
Antivirais/farmacologia , Antivirais/toxicidade , Hepatite B Crônica/tratamento farmacológico , Nucleosídeos/farmacologia , Nucleosídeos/toxicidade , Pirimidinonas/farmacologia , Pirimidinonas/toxicidade , Administração Oral , Animais , Antivirais/administração & dosagem , Testes de Carcinogenicidade , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Tolerância a Medicamentos , Feminino , Humanos , Macaca fascicularis , Masculino , Camundongos , Camundongos Transgênicos , Testes de Mutagenicidade , Degeneração Neural/induzido quimicamente , Nucleosídeos/administração & dosagem , Gravidez , Pirimidinonas/administração & dosagem , Coelhos , Ratos , Ratos Sprague-Dawley , Reprodução/efeitos dos fármacos , Segurança , Telbivudina , Timidina/análogos & derivados
15.
J Pharm Biomed Anal ; 47(4-5): 985-9, 2008 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-18499386

RESUMO

A novel method for the quantitation of yonkenafil, a new synthetic phosphodiesterase V inhibitor, in rat plasma using high-performance liquid chromatography/tandem mass spectrometry (LC-MS/MS) has been developed. The analyte and internal standard (diazepam) were extracted from plasma (100 microl) by liquid-liquid extraction and separated on a C18 column using 10mM ammonium acetate buffer: methanol (15:85, v/v) as mobile phase in a run time of 3.0 min. The detector was a Q-trap mass spectrometer with an ESI interface operating in the multiple reaction monitoring (MRM) mode. The assay was linear over the concentration range 1.0-1000 ng/ml with a limit of detection of 0.20 ng/ml. Intra- and inter-day precision (as relative standard deviation) were both within 8.45% with good accuracy. The method was successfully applied to a preclinical pharmacokinetic study of yonkenafil in rat after sublingual, oral and intravenous administration. The results demonstrate that the sublingual route gives a higher bioavailablity than the oral route and may represent a useful alternative route of yonkenafil administration.


Assuntos
Cromatografia Líquida/métodos , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5/farmacocinética , Inibidores da Fosfodiesterase 5 , Inibidores de Fosfodiesterase/sangue , Inibidores de Fosfodiesterase/farmacocinética , Pirimidinonas/sangue , Pirimidinonas/farmacocinética , Pirróis/sangue , Pirróis/farmacocinética , Espectrometria de Massas em Tandem/métodos , Acetatos/química , Administração Oral , Administração Sublingual , Animais , Disponibilidade Biológica , Soluções Tampão , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5/administração & dosagem , Avaliação Pré-Clínica de Medicamentos , Estabilidade de Medicamentos , Jejum , Concentração de Íons de Hidrogênio , Injeções Intravenosas , Masculino , Metanol/química , Estrutura Molecular , Inibidores de Fosfodiesterase/administração & dosagem , Inibidores de Fosfodiesterase/química , Pirimidinonas/administração & dosagem , Pirimidinonas/química , Pirróis/administração & dosagem , Pirróis/química , Controle de Qualidade , Distribuição Aleatória , Ratos , Ratos Wistar , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização por Electrospray , Fatores de Tempo
17.
Eur J Obstet Gynecol Reprod Biol ; 133(1): 60-3, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16989938

RESUMO

OBJECTIVE: To evaluate the biochemical and morphological effects in rats subjected to three different dose associations of the protease inhibitors lopinavir and ritonavir administered throughout the entire period of pregnancy. STUDY DESIGN: The animals were treated throughout pregnancy with daily oral doses of lopinavir+ritonavir starting at the day one of pregnancy, and were divided into four groups: E1, 13.3+3.3 mg/kg; E2, 39.9+9.9 mg/kg; E3, 119.7+29.9 mg/kg and C, control (drug vehicle, propyleneglycol). The animals were then sacrificed and maternal blood and fetal and maternal organ samples were taken for morphological and biochemical analysis. RESULTS: No major changes were identified in the group treated with the lowest dose as compared with the control. In the group E2, we found hepatocytes with signs of atrophy, eosinophilic cytoplasm, picnotic nuclei and vasodilatation. The proximal convoluted tubules of maternal kidneys showed eosinophilic areas and hyperchromatic nuclei, as well as signs of vasodilation. In the group treated with the highest dose (group E3), in the maternal kidneys and livers, the morphological changes were similar to those found in E2, although more prominent. Regarding the fetal organs, the single abnormality observed was some liver vasodilation in the group E3 (highest dose). The treatment with lopinavir+ritonavir caused discrete, yet significant, alterations of aspartate aminotransferase activity, blood urea nitrogen and creatinine plasma levels. CONCLUSIONS: Our results showed that the administration of a combination of lopinavir plus ritonavir to pregnant rats can cause morphological as well as functional changes in maternal and fetal liver and kidneys and, in higher than therapeutic doses, might be toxic to those animals.


Assuntos
Inibidores da Protease de HIV/toxicidade , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Pirimidinonas/toxicidade , Ritonavir/toxicidade , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Nitrogênio da Ureia Sanguínea , Creatinina/sangue , Combinação de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Feminino , Inibidores da Protease de HIV/administração & dosagem , Inibidores da Protease de HIV/farmacologia , Rim/embriologia , Rim/patologia , Fígado/embriologia , Fígado/patologia , Lopinavir , Gravidez , Pirimidinonas/administração & dosagem , Pirimidinonas/farmacologia , Ratos , Ratos Wistar , Ritonavir/administração & dosagem , Ritonavir/farmacologia
18.
Artigo em Inglês | MEDLINE | ID: mdl-15768732

RESUMO

PURPOSE: Highly active antiretroviral therapy (HAART) can be associated with diarrhea and other gastrointestinal (GI) side effects. Reducing these side effects may improve treatment durability and quality of life (QOL). This study assessed the impact of nutritional co-therapies known to reduce diarrhea in HIV-positive men treated with nelfinavir (NFV)- or lopinavir/ritonavir (LPV/r)-containing regimens. METHODS: Thirty-five HIV-positive men treated with NFV (n = 27) or LPV/r (n = 8) with diarrhea (> or = two liquid stools/day [d]) participated in a 12-week prospective study. Twenty-eight subjects were randomly assigned supplements (S), seven received standard of care (C). Group S received probiotics (1.2g/d) and soluble fiber (11g/d). If diarrhea persisted at week 4, 30g/d L-Glutamine (GLN) was added. Diarrhea incidence, as well as supplement and antidiarrheal use, was assessed monthly. RESULTS: Weight, CD4 count, and HIV RNA were unchanged in both groups. Diarrhea completely resolved in 10 of 28 (36 percent) S subjects. The mean (+/-SD) number of stools/d declined [3.40+/-1.25 to 2.54+/-1.34 (p < 0.01)]. Diarrhea (loose, watery stools/d) lessened in S from 2.84+/-1.42 to 0.74+/-1.03 (p < 0.0001). Fifteen S subjects did not obtain full relief with probiotics and fiber, but stools/d decreased from 4.08+/-1.35 to 3.06+/-1.68 (p < 0.05) after starting GLN. In C, stools/d, 4.14+/-4.86 to 3.44+/-1.68(p = 0.678) and incidence of diarrhea/d, 3.00+/-4.82 to 1.36+/-1.29 (p= 0.361) was unchanged. In S, loperamide use decreased from 1.69+/-2.34 to 0.31+/-0.69 mg/d (p < 0.01); 18 versus eight subjects used loperamide at 0 and 12 weeks, respectively. CONCLUSION: Probiotics, soluble fiber, and GLN significantly reduced diarrhea for subjects receiving NFV or LPV/r. Nutritional co-therapies show clinical benefit in HIV-positive men with diarrhea.


Assuntos
Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Diarreia/prevenção & controle , Fibras na Dieta/uso terapêutico , Glutamina/uso terapêutico , Inibidores da Protease de HIV/efeitos adversos , Nelfinavir/efeitos adversos , Probióticos/uso terapêutico , Pirimidinonas/efeitos adversos , Ritonavir/efeitos adversos , Adulto , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Contagem de Linfócito CD4 , Diarreia/induzido quimicamente , Diarreia/classificação , Inibidores da Protease de HIV/administração & dosagem , Humanos , Lopinavir , Masculino , Nelfinavir/administração & dosagem , Probióticos/administração & dosagem , Pirimidinonas/administração & dosagem , Qualidade de Vida , Ritonavir/administração & dosagem , Índice de Gravidade de Doença , Resultado do Tratamento
20.
Pest Manag Sci ; 58(2): 161-6, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11852640

RESUMO

The insecticidal activities of materials derived from the fruit of star anise, Illicium verum, against adults of Blattella germanica were examined by direct contact application and fumigation methods, and compared with those of DDVP, deltamethrin and hydramethylnon. The biologically active constituent of the Illicium fruit was characterized as the phenylpropene, (E)-anethole, by spectroscopic analysis. In a filter paper diffusion test with females, (E)-anethole caused 80.3% mortality at 0.159 mg cm-2 at 1 and 3 days after treatment (DAT), whereas 16.7% mortality at 3 DAT was achieved at 0.079 mg cm-2. DDVP and deltamethrin gave > 90% mortality at 0.019 mg cm-2 at 1 DAT. At 0.009 mg cm-2, DDVP and deltamethrin showed 73.3 and 60% mortality at 1 DAT, respectively, but 93.3 and 76.7% mortality at 3 DAT. Hydramethylnon exhibited 0 and 93.3% mortality at 0.159 mg cm-2 at 1 and 3 DAT, respectively, whereas 6.7% mortality at 3 DAT was observed at 0.079 mg cm-2. In a fumigation test with females, (E)-anethole was much more effective in closed cups than in open ones, indicating that the insecticidal activity of the compound was largely attributable to fumigant action. (E)-Anethole and DDVP caused 100% mortality at 0.398 and 0.051 mg cm-2 4 and 1 h after treatment, respectively. (E)-Anethole showed 46.7% mortality at 0.199 mg cm-2 at 3 DAT, whereas deltamethrin and hydramethylnon at 0.796 mg cm-2 was ineffective for 3-day period. As naturally occurring insect-control agents, the I verum fruit-derived materials described could be useful for managing populations of B germanica.


Assuntos
Anisóis/toxicidade , Blattellidae/efeitos dos fármacos , Illicium/química , Inseticidas/toxicidade , Extratos Vegetais/toxicidade , Derivados de Alilbenzenos , Animais , Anisóis/administração & dosagem , Anisóis/química , Diclorvós/administração & dosagem , Diclorvós/toxicidade , Feminino , Frutas/química , Inseticidas/química , Masculino , Estrutura Molecular , Nitrilas , Piretrinas/administração & dosagem , Piretrinas/toxicidade , Pirimidinonas/administração & dosagem , Pirimidinonas/toxicidade , Fatores de Tempo
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