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1.
Cancer Chemother Pharmacol ; 79(4): 759-766, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28289864

RESUMO

OBJECTIVES: We studied the relation between the polymorphism of P-glycoprotein (P-gp) and of breast cancer resistance protein (BCRP), encoded by ABCB1 and ABCG2 genes, respectively, and the pharmacokinetic variability and clinical response during the treatment with sorafenib of hepatocellular carcinoma. METHODS: At the Paul Brousse Hospital in Villejuif, France, 47 consecutive patients with advanced HCC treated with a single agent sorafenib, were enrolled. Sorafenib exposure was measured by its plasma concentration 3 h after oral administration of 400 mg (bid) by liquid chromatography. All enrolled patients were genotyped for ABCB1 (rs2032582; rs1045642) and ABCG2 (rs2231137; rs2231142; rs2622604) by blood genomic DNA extraction and Mass ARRAY genotyping. The clinical response was evaluated after 3months of treatment according to the RECIST criteria. KEY FINDINGS: Significant associations between sorafenib exposure and the studied polymorphisms were observed for ABCB1 3435C>T, ABCG2 34G>A, ABCG2 1143C>T and ABCG2 421C>A, but not for ABCB1 2677G>TA SNP. In heterozygous patients for ABCB1 3435 C>T, ABCG2 34 G>A and ABCG2 1143 C>T polymorphisms were significantly associated with the lowest sorafenib plasma levels. Those patients presented a tendency to have the best clinical evolution. CONCLUSION: Heterozygous forms of the studied polymorphisms could be associated with a better therapeutic response.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Antineoplásicos/uso terapêutico , Neoplasias da Mama/genética , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Proteínas de Neoplasias/genética , Niacinamida/análogos & derivados , Compostos de Fenilureia/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/farmacocinética , Neoplasias da Mama/tratamento farmacológico , DNA/genética , Monitoramento de Medicamentos , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Niacinamida/farmacocinética , Niacinamida/uso terapêutico , Compostos de Fenilureia/farmacocinética , Polimorfismo Genético/genética , Polimorfismo de Nucleotídeo Único/genética , Inibidores de Proteínas Quinases/farmacocinética , Sorafenibe , Resultado do Tratamento
2.
J Alzheimers Dis ; 49(2): 287-300, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26484906

RESUMO

The involvement of transporters located at the blood-brain barrier (BBB) has been suggested in the control of cerebral Aß levels, and thereby in Alzheimer's disease (AD). However, little is known about the regulation of these transporters at the BBB in animal models of AD. In this study, we investigated the BBB expression of Aß influx (Rage) and efflux (Abcb1-Abcg2-Abcg4-Lrp-1) transporters and cholesterol transporter (Abca1) in 3-18-month-old 3xTg-AD and control mice. The age-dependent effect of BBB transporters regulation on the brain uptake clearance (Clup) of [3H]cholesterol and [3H]Aß1 - 40 was then evaluated in these mice, using the in situ brain perfusion technique. Our data suggest that transgenes expression led to the BBB increase in Aß influx receptor (Rage) and decrease in efflux receptor (Lrp-1). Our data also indicate that mice have mechanisms counteracting this increased net influx. Indeed, Abcg4 and Abca1 are up regulated in 3- and 3/6-month-old 3xTg-AD mice, respectively. Our data show that the balance between the BBB influx and efflux of Aß is maintained in 3 and 6-month-old 3xTg-AD mice, suggesting that Abcg4 and Abca1 control the efflux of Aß through the BBB by a direct (Abcg4) or indirect (Abca1) mechanism. At 18 months, the BBB Aß efflux is significantly increased in 3xTg-AD mice compared to controls. This could result from the significant up-regulation of both Abcg2 and Abcb1 in 3xTg-AD mice compared to control mice. Thus, age-dependent regulation of several Aß and cholesterol transporters at the BBB could ultimately limit the brain accumulation of Aß.


Assuntos
Envelhecimento , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Barreira Hematoencefálica/fisiopatologia , Encéfalo/metabolismo , Fragmentos de Peptídeos/metabolismo , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/metabolismo , Doença de Alzheimer/genética , Animais , Transporte Biológico/genética , Barreira Hematoencefálica/metabolismo , Isótopos de Carbono/metabolismo , Colesterol/metabolismo , Modelos Animais de Doenças , Humanos , Lipoproteínas/metabolismo , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Camundongos , Camundongos Transgênicos , Receptores de LDL/metabolismo , Sacarose/metabolismo , Trítio/metabolismo , Proteínas Supressoras de Tumor/metabolismo
3.
Crit Care ; 19: 40, 2015 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-25886890

RESUMO

INTRODUCTION: As a result of drug sequestration and increased volume of distribution, the extracorporeal membrane oxygenation (ECMO) procedure might lead to a decrease in drug concentrations during a patient's treatment. The aim of this study was to evaluate sedative, antibiotic and immunosuppressive drug loss in ECMO circuit using ex-vivo and in-vitro experiments. METHODS: Blood concentrations of propofol, midazolam, cyclosporine and vancomycin were measured in an ex-vivo ECMO circuit primed with whole human blood, and compared to controls stored in polypropylene tubes. In vitro experiments were also conducted to further explore the role of temperature, oxygen exposure and polyvinylchloride surfaces on propofol loss in the ECMO circuit. RESULTS: Propofol concentration decreased rapidly; 70% of its baseline concentration was lost after only 30 minutes, and only 11% remained after five hours (P <0.001 for the comparison with control polypropylene tube propofol concentration). Further experiments demonstrated that oxygen exposure and contact with polyvinylchloride tubing were respectively responsible for 70% and 85% of propofol loss after 45 minutes. Midazolam concentration also rapidly decreased in the ECMO circuit, with only 54% and 11% of baseline concentration being detected at 30 minutes and 24 hours respectively (P = 0.01 versus control). Alternatively, cyclosporine concentration remained stable for the five first hours, then decreased to 78% and 73% of the baseline value after 24 hours and 48 hours, (P = 0.35 versus control). Lastly, vancomycin concentration remained stable in the ECMO circuit for the 48-hour experimental protocol. CONCLUSIONS: We observed important losses of propofol and midazolam, while cyclosporine concentration decreased slowly and moderately, and vancomycin concentration remained unchanged in the ex-vivo ECMO circuit primed with whole human blood. These data might help intensive care unit physicians planning clinical trials with a final objective to better adapt doses of these drugs while treating critically ill ECMO patients.


Assuntos
Anti-Infecciosos/sangue , Ciclosporina/sangue , Oxigenação por Membrana Extracorpórea/instrumentação , Hipnóticos e Sedativos/sangue , Midazolam/sangue , Propofol/sangue , Vancomicina/sangue , Anti-Infecciosos/uso terapêutico , Sangue , Estado Terminal , Ciclosporina/uso terapêutico , Monitoramento de Medicamentos , Humanos , Hipnóticos e Sedativos/uso terapêutico , Midazolam/uso terapêutico , Modelos Biológicos , Cloreto de Polivinila/efeitos adversos , Propofol/uso terapêutico , Vancomicina/uso terapêutico
4.
J Neurooncol ; 122(2): 273-81, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25794638

RESUMO

Glioblastoma (GBM) is the most common primary malignant brain tumour in adults. Prognosis of GBM patients is poor with median overall survival around 15 months. Temozolomide is the chemotherapeutic agent used in the standard of care of newly diagnosed GBM patients relying on radiotherapy with concurrent chemotherapy followed by chemotherapy alone. Irinotecan has shown some efficacy in recurrent malignant gliomas. Bevacizumab has been combined with irinotecan in the treatment of recurrent GBM and with temozolomide in newly diagnosed GBM. As the efficacy of GBM treatments relies on their brain distribution through the blood brain barrier, the aim of the present preclinical work was to study, in in vivo models, the impact of bevacizumab on brain and tumor distribution of temozolomide and irinotecan. Our results show that bevacizumab pre-treatment was associated with a reduced temozolomide brain distribution in tumor-free mice. In tumor bearing mice, bevacizumab increased temozolomide tumor distribution, although not statistically significant. In both tumor-free and tumor-bearing mice, bevacizumab does not modify brain distribution of irinotecan and its metabolite SN-38. Bevacizumab impacts brain distribution of some anti-tumor drugs and potentially their efficacy in GBM. Further studies are warranted to investigate other therapeutic combination.


Assuntos
Bevacizumab/farmacologia , Neoplasias Encefálicas/metabolismo , Encéfalo/metabolismo , Camptotecina/análogos & derivados , Dacarbazina/análogos & derivados , Inibidores da Angiogênese/farmacologia , Animais , Antineoplásicos Alquilantes/farmacocinética , Antineoplásicos Fitogênicos/farmacocinética , Encéfalo/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Camptotecina/farmacocinética , Linhagem Celular Tumoral , Dacarbazina/farmacocinética , Feminino , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Humanos , Irinotecano , Camundongos , Camundongos Nus , Transplante de Neoplasias , Temozolomida , Distribuição Tecidual
5.
Cancer Chemother Pharmacol ; 74(1): 185-93, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24867782

RESUMO

Glioblastoma (GBM), the most common primary brain tumor in adults, is usually rapidly fatal with median survival duration of only 15 months and a 3-year survival rate of <7 %. Temozolomide (TMZ) is the only anticancer drug that has improved survival in GBM when administered with concomitant radiotherapy. Irinotecan (CPT-11) has also shown efficacy in recurrent gliomas monotherapy with moderate response. As the efficacy of GBM treatments relies on their brain distribution through the blood-brain barrier (BBB), the aim of the present work was to study, on an in vivo model, the brain distribution of TMZ, CPT-11 and its active metabolite, SN-38. We have focussed on the role of ABCB1, the main efflux transporter at the BBB level, through pharmacokinetics studies in CF1 mdr1a(+/+) and mdr1a(-/-) mice. Our results show that TMZ, CPT-11 and SN-38 are transported by ABCB1 at the BBB level with brain/plasma ratios of 1.1, 2.1 and 2.3, respectively.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos Alquilantes/farmacocinética , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Camptotecina/análogos & derivados , Dacarbazina/análogos & derivados , Inibidores da Topoisomerase I/farmacocinética , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Animais , Antineoplásicos Alquilantes/administração & dosagem , Antineoplásicos Alquilantes/sangue , Antineoplásicos Alquilantes/metabolismo , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/sangue , Antineoplásicos Fitogênicos/metabolismo , Antineoplásicos Fitogênicos/farmacocinética , Transporte Biológico/efeitos dos fármacos , Barreira Hematoencefálica/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Camptotecina/administração & dosagem , Camptotecina/sangue , Camptotecina/metabolismo , Camptotecina/farmacocinética , Dacarbazina/administração & dosagem , Dacarbazina/sangue , Dacarbazina/metabolismo , Dacarbazina/farmacocinética , Feminino , Meia-Vida , Injeções Intraperitoneais , Irinotecano , Camundongos , Camundongos Endogâmicos , Camundongos Mutantes , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Pró-Fármacos/administração & dosagem , Pró-Fármacos/metabolismo , Pró-Fármacos/farmacocinética , Temozolomida , Distribuição Tecidual , Inibidores da Topoisomerase I/administração & dosagem , Inibidores da Topoisomerase I/sangue , Inibidores da Topoisomerase I/metabolismo
6.
Fundam Clin Pharmacol ; 28(6): 652-60, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24588516

RESUMO

In a previous study, we showed that cetuximab, a monoclonal antibody directed towards epidermal growth factor receptor, could inhibit P-glycoprotein (P-gp), an efflux protein of ATP-binding cassette family, and lead to an increased P-gp substrate intracellular concentration. Cetuximab is given with irinotecan to patients with metastasis colorectal cancer who did not respond to irinotecan-based therapy. The mechanism of this successful clinical reversion remains unknown. As irinotecan is a P-gp substrate, we tested here whether cetuximab could modify irinotecan concentration in mice. Therefore, concentrations of irinotecan and of its active metabolite SN-38 were measured by HPLC in plasma and tumour of mice bearing a human colorectal carcinoma xenograft when irinotecan is given orally alone or after a pretreatment with cetuximab. Pharmacokinetic analysis showed no significant modification of irinotecan concentrations but a significant increase (1.7-fold) in SN-38 AUCs in plasma and in tumour after a pretreatment with cetuximab. Those results suggest that cetuximab influence irinotecan distribution into tissues probably due to inhibition of P-gp. As SN-38 is 200-fold more potent than irinotecan, cetuximab could reverse irinotecan resistance by an effect on its active metabolite. Inhibiting SN-38 efflux by P-gp drug transporters in biliary system and tumour can lead to pharmacokinetic modification and a higher anticancer efficacy.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Camptotecina/análogos & derivados , Neoplasias Colorretais/tratamento farmacológico , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Administração Oral , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Área Sob a Curva , Transporte Biológico/efeitos dos fármacos , Camptotecina/farmacocinética , Camptotecina/farmacologia , Cetuximab , Neoplasias Colorretais/patologia , Interações Medicamentosas , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Humanos , Irinotecano , Camundongos , Camundongos Nus , Distribuição Tecidual , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Neuropharmacology ; 81: 311-7, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24631967

RESUMO

We evaluated the integrity and function of the blood-brain barrier in 3xTg-AD mice aged 3-18 months and in APP/PS1 mice aged 8-months to determine the impacts of changes in amyloid and tau proteins on the brain vascular changes. The vascular volume (Vvasc) was sub-normal in 3xTg-AD mice aged from 6 to 18 months, but not in the APP/PS1 mice. The uptakes of [(3)H]-diazepam by the brains of 3xTg-AD, APP/PS1 and their age-matched control mice were similar at all the times studied, suggesting that the simple diffusion of small solutes is unchanged in transgenic animals. The uptake of d-glucose by the brains of 18-month old 3xTg-AD mice, but not by those of 8-month old APP/PS1 mice, was reduced compared to their age-matched controls. Accordingly, the amount of Glut-1 protein was 1.4 times lower in the brain capillaries of 18 month-old 3xTg-AD mice than in those of age-matched control mice. We conclude that the brain vascular volume is reduced early in 3xTg-AD mice, 6 months before the appearance of pathological lesions, and that this reduction persists until they are at least 18 months old. The absence of alterations in the BBB of APP/PS1 mice suggests that hyperphosphorylated tau proteins contribute to the vascular changes that occur in AD.


Assuntos
Doença de Alzheimer/patologia , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/fisiologia , Encéfalo/patologia , Circulação Cerebrovascular/genética , Transportador de Glucose Tipo 1/metabolismo , Fatores Etários , Doença de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Diazepam/metabolismo , Modelos Animais de Doenças , Lateralidade Funcional , Glucose/metabolismo , Humanos , Camundongos , Camundongos Transgênicos , Microvasos/patologia , Microvasos/fisiopatologia , Mutação/genética , Presenilina-1/genética , Sacarose/metabolismo , Proteínas tau/genética
8.
Am J Physiol Endocrinol Metab ; 306(6): E668-80, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24425764

RESUMO

The oligopeptide transporter peptide cotransporter-1 Slc15a1 (PEPT1) plays a major role in the regulation of nitrogen supply, since it is responsible for 70% of the dietary nitrogen absorption. Previous studies demonstrated that PEPT1 expression and function in jejunum are reduced in diabetes and obesity, suggesting a nitrogen malabsorption from the diet. Surprisingly, we reported here a decrease in gut nitrogen excretion in high-fat diet (HFD)-fed mice and further investigated the mechanisms that could explain this apparent contradiction. Upon HFD, mice exhibited an increased concentration of free amino acids (AAs) in the portal vein (60%) along with a selective increase in the expression of two AA transporters (Slc6a20a, Slc36a1), pointing to a specific and adaptive absorption of some AAs. A delayed transit time (+40%) and an increased intestinal permeability (+80%) also contribute to the increase in nitrogen absorption. Besides, HFD mice exhibited a 2.2-fold decrease in fecal DNA resulting from a reduction in nitrogen catabolism from cell desquamation and/or in the intestinal microbiota. Indeed, major quantitative (2.5-fold reduction) and qualitative alterations of intestinal microbiota were observed in feces of HFD mice. Collectively, our results strongly suggest that both increased AA transporters, intestinal permeability and transit time, and changes in gut microbiota are involved in the increased circulating AA levels. Modifications in nitrogen homeostasis provide a new insight in HFD-induced obesity and glucose intolerance; however, whether these modifications are beneficial or detrimental for the HFD-associated metabolic complications remains an open issue.


Assuntos
Sistemas de Transporte de Aminoácidos/biossíntese , Aminoácidos/metabolismo , Modelos Animais de Doenças , Intolerância à Glucose/metabolismo , Absorção Intestinal , Mucosa Intestinal/metabolismo , Obesidade/metabolismo , Simportadores/biossíntese , Alostase , Sistemas de Transporte de Aminoácidos/genética , Sistemas de Transporte de Aminoácidos/metabolismo , Aminoácidos/sangue , Animais , DNA/análise , Dieta Hiperlipídica/efeitos adversos , Dipeptidil Peptidase 4/química , Dipeptidil Peptidase 4/genética , Dipeptidil Peptidase 4/metabolismo , Fezes/química , Fezes/microbiologia , Regulação da Expressão Gênica , Intolerância à Glucose/etiologia , Intolerância à Glucose/microbiologia , Intolerância à Glucose/patologia , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/crescimento & desenvolvimento , Bactérias Gram-Positivas/isolamento & purificação , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Intestinos/microbiologia , Intestinos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nitrogênio/análise , Nitrogênio/metabolismo , Obesidade/etiologia , Obesidade/microbiologia , Obesidade/patologia , Transportador 1 de Peptídeos , Simportadores/genética , Simportadores/metabolismo
9.
J Alzheimers Dis ; 36(3): 555-61, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23635403

RESUMO

The influx of amyloid-ß peptide (Aß) across the blood-brain barrier is partly mediated by the receptor for advanced glycation end products (RAGE). But other transporters, like Oatp (organic anion transporter polypeptide, SLC21) transporters, could also be involved. We used in situ brain perfusion to show that rosuvastatin and taurocholate, two established Oatp1a4 substrates, decreased (5-fold) the Clup of [3H]Aß while L-thyroxine increased it (5.5-fold). We demonstrated an interaction between Aß and Oatp1a4 by co-immunoprecipitation and western blotting experiments, supporting the hypothesis that the rosuvastatin- and taurocholate-sensitive transporter was Oatp1a4. In conclusion, our results suggest that, in mice, the brain uptake of Aß is partly mediated by Oatp1a4 and that L-thyroxine may play a crucial role in the inhibition of brain Aß clearance.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Barreira Hematoencefálica/metabolismo , Proteínas de Transporte de Cátions Orgânicos/metabolismo , Transporte Proteico/fisiologia , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Fluorbenzenos/farmacologia , Camundongos , Transporte Proteico/efeitos dos fármacos , Pirimidinas/farmacologia , Rosuvastatina Cálcica , Sulfonamidas/farmacologia , Ácido Taurocólico/farmacologia , Tiroxina/farmacologia
10.
Biomed Chromatogr ; 27(7): 889-93, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23436249

RESUMO

A sensitive and accurate liquid chromatography method with mass spectrometry detection was developed and validated for the quantification of temozolomide in mouse plasma and brain. Theophyllin was used as the internal standard. A single-step protein precipitation was used for plasma and brain sample preparation. The method was validated with respect to selectivity, extraction recovery, linearity, intra- and inter-day precision and accuracy, limit of quantification and stability. The method has a limit of quantification of 50 ng/mL for temozolomide in plasma and 125 ng/g in brain. This method was used successfully to perform brain and plasma pharmacokinetic studies of temozolomide in mice after intraperitoneal administration.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Dacarbazina/análogos & derivados , Espectrometria de Massas em Tandem/métodos , Animais , Química Encefálica , Dacarbazina/análise , Dacarbazina/sangue , Dacarbazina/química , Dacarbazina/farmacocinética , Feminino , Análise dos Mínimos Quadrados , Camundongos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Temozolomida , Distribuição Tecidual
11.
Fundam Clin Pharmacol ; 27(4): 434-42, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22458846

RESUMO

KRAS mutation is a negative predictive prognostic factor during metastatic colorectal cancer treatment with antiepidermal growth factor receptor antibodies. For affected patients, new therapeutics must be explored. Our objective was to study efficacy of two drugs with different mechanisms of action, everolimus (mTOR inhibitor) and lapatinib (tyrosine kinase inhibitor), in a mouse xenograft model. We chose a model obtained after engraftment of a tumor originating from a human tumor collection. The patient was affected by a metastasis colorectal carcinoma resistant to cetuximab with KRAS mutation. From a previous study in mice, we know that everolimus is a P-glycoprotein (P-gp) substrate and that a lapatinib pretreatment increases significantly (2.6-fold) everolimus AUC by inhibiting its intestinal P-gp efflux. We hence tested the effect of these drugs alone or combined. Mice bearing the xenografts were divided in four groups: control, lapatinib, everolimus, and L/E group (L/E: 2 days of lapatinib 200 mg/kg and then 3 days of everolimus 1 mg/kg). Tumor volumes and treatment toxicities were evaluated. Sixteen days after treatment initiation, the group L/E was the first one in which tumor volume average was significantly lower than the one of control group (193 ± 90 vs. 395 ± 171 mm(3) ; P = 0.0025). After 4 weeks of treatment, inhibition of tumor growth in lapatinib, everolimus, and L/E groups reached, respectively, 49, 53, and 57%. Each drug showed significant antitumor activity. Only moderate hematologic toxicity signs were observed. These results lead to new perspectives for new oral drugs in metastatic KRAS-mutated colorectal cancer resistant to standard chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Quinazolinas/farmacologia , Sirolimo/análogos & derivados , Proteínas ras/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Animais , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Resistencia a Medicamentos Antineoplásicos , Everolimo , Feminino , Humanos , Lapatinib , Camundongos , Camundongos Nus , Mutação , Quinazolinas/administração & dosagem , Sirolimo/administração & dosagem , Sirolimo/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas ras/metabolismo
12.
Ther Drug Monit ; 34(6): 686-94, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23131698

RESUMO

BACKGROUND: The aim of this study was, using routine drug monitoring data, to identify patient characteristics that may influence everolimus (EVE) pharmacokinetic parameters and to develop a population pharmacokinetic model to predict EVE whole blood concentrations in cardiac recipients. METHODS: Fifty-nine patients were enrolled in the prospective study. Patient's characteristics were recorded including biological covariates and treatments. CYP3A5 and ABCB1 polymorphisms were determined. Seven hundred seventy-five EVE blood samples were collected for routine drug monitoring. Population pharmacokinetic modeling was carried out using the nonlinear mixed-effects modeling program. Results were analyzed according to a 1-compartment pharmacokinetic model with linear absorption and elimination. The model was evaluated using a bootstrap method and a visual predictive check procedure. RESULTS: The pharmacokinetic of EVE in cardiac recipients was best described by a 1-compartment model. Interindividual variability was best described by an exponential error model and residual error by a proportional plus additive error model. Estimation of EVE apparent clearance (3.33 ± 0.20 L/h) and apparent volume of distribution (146 ± 33 L) were in accordance with previously published data. Bilirubinemia and cyclosporine significantly influenced EVE clearance. Some covariates that were expected to influence EVE clearance, for example, ABCB1 and CYP3A5 polymorphisms, were not evidenced. No covariates influenced the volume of distribution of EVE. CONCLUSIONS: This study is the first population pharmacokinetic model of EVE in heart transplantation patients. It allows a better description of the pharmacokinetics of EVE. The present population pharmacokinetic model allows estimating a priori and a posteriori EVE concentrations in cardiac recipients and could limit the over and under drug exposure in this population.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Citocromo P-450 CYP3A/genética , Rejeição de Enxerto/prevenção & controle , Transplante de Coração/efeitos adversos , Imunossupressores/farmacocinética , Polimorfismo de Nucleotídeo Único , Sirolimo/análogos & derivados , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Citocromo P-450 CYP3A/metabolismo , Interações Medicamentosas , Everolimo , Feminino , Seguimentos , Estudos de Associação Genética , Humanos , Imunossupressores/sangue , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Paris , Estudos Prospectivos , Sirolimo/sangue , Sirolimo/farmacocinética , Sirolimo/uso terapêutico , Adulto Jovem
13.
Life Sci ; 91(17-18): 843-51, 2012 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-23047021

RESUMO

AIMS: Interferon-alpha (IFN-α) was shown to reduce P-glycoprotein (P-gp) expression and activity in several tissues. The purpose of this study was to evaluate the impact of IFN-α pretreatment on the antitumoral and antimetastatic, Docetaxel (DTX, P-gp substrate), on Lewis Lung Cancer (3LL) bearing mice and to correlate it to DTX pharmacokinetics. MAIN METHODS: Six groups of C57/Bl6 mice received subcutaneous (s.c.) 2.10(6) 3LL cells, then IFN-α 4MIU/kg for 7days, then received or did not receive i.v. or oral DTX (30mg/kg). Pharmacokinetic studies were done on a part of the mice: DTX concentrations were assessed in plasma and tumors, where AUC were estimated with the Bailer method, and half-lives and MRT were determined with a non-compartmental analysis. Tumor growth was assessed more than 21days: animals were then sacrificed and lung metastases number was counted. Kaplan-Meier analysis was made to analyze survival data during the survey period. KEY FINDINGS: DTX i.v. associated with IFN-α significantly improved mouse survival (19.6±0.6days vs. 17.1±0.8days for control mice, p=0.047) with greater antimetastatic effects (87.5% reduction in the number of metastases compared to control mice). The effect on tumor growth was not modified within the IFN-α/DTX i.v. treated groups when compared to mice receiving DTX i.v. alone. The pharmacokinetic analysis showed an increase of DTX concentrations in tumors at 30min after DTX i.v. administration and an increase in the oral bioavailability of orally given DTX following an IFN-α treatment. SIGNIFICANCE: Our study established that IFN-α increases DTX uptake in tumors, improves its antitumoral efficiency and improves animals' survival.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Lewis/tratamento farmacológico , Fatores Imunológicos/uso terapêutico , Interferon-alfa/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Taxoides/uso terapêutico , Animais , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Lewis/patologia , Linhagem Celular Tumoral , Docetaxel , Fatores Imunológicos/farmacologia , Interferon-alfa/farmacologia , Estimativa de Kaplan-Meier , Pulmão/efeitos dos fármacos , Pulmão/patologia , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Endogâmicos C57BL , Metástase Neoplásica/tratamento farmacológico , Taxoides/farmacocinética , Taxoides/farmacologia
14.
J Pharm Biomed Anal ; 66: 278-81, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22571954

RESUMO

A reliable ultra high performance liquid chromatography tandem mass spectrometry method has been developed for the determination of everolimus in human peripheral blood mononuclear cells (PBMCs). Protein precipitation was used for sample preparation. Analysis was performed on an UPLC Waters Acquity system. Chromatography was carried out using a cartridge column MassTrak TDM C18 (2.1×10 mm) with 0.1% formic acid and 2 mM of ammonium acetate in water and 0.1% formic acid and 2mM of ammonium acetate in methanol mixture as a mobile phase delivered at a flow rate of 0.4 mL/min in gradient mode. The assay was linear over a range of 0-12.5 ng/mL. The analysis of quality control samples at 2.5, 5.0 and 10.0 ng/mL demonstrated good precision with relative standard deviation of less than 15%. Recoveries at concentrations of 2.5, 5.0 and 10.0 ng/mL were all greater than 83%. The method was successfully applied to the analysis of everolimus in PBMCs from blood samples of transplant recipients.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Leucócitos Mononucleares/metabolismo , Sirolimo/análogos & derivados , Espectrometria de Massas em Tandem/métodos , Everolimo , Seguimentos , Transplante de Coração/métodos , Humanos , Imunossupressores/análise , Controle de Qualidade , Reprodutibilidade dos Testes , Sirolimo/análise
15.
J Pharm Biomed Anal ; 66: 325-33, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22551773

RESUMO

A sensitive and accurate liquid chromatography method with mass spectrometry detection using MRM in positive ion mode was developed and validated for the simultaneous quantification of irinotecan (CPT-11) and 7-ethyl-10-hydroxycamptothecin (SN-38) in mouse plasma and brain. Camptothecin (CPT) was used as internal standard. A single step protein precipitation was used for plasma sample preparation, and a liquid-liquid extraction was needed for brain sample preparation. The method was validated with respect to selectivity, extraction recovery, linearity, intra- and inter-day precision and accuracy, limit of quantification and stability. Limits of quantification were 5 ng/mL for CPT-11 and SN-38 in plasma samples and 1.25 ng/g in brain. Linear calibration curves were obtained over concentration ranges of 5-5000 ng/mL in plasma and 1.25-1250 ng/g in brain for CPT-11 and SN-38. The intra-day and inter-day variation (relative standard deviation, R.S.D.) found to be less than 15% for both substances in both media. Stability studies showed that plasma carboxylesterase had to be inactivated in order to prevent in vitro conversion of CPT-11 into SN-38. Zinc sulfate (1 M) was used to inactivate the enzyme before sample storage. Brain samples did not require enzyme inactivation. This method was successfully applied to perform brain and plasma pharmacokinetic studies of CPT-11 and SN-38 in mice after intraperitoneal administration.


Assuntos
Antineoplásicos Fitogênicos/farmacocinética , Camptotecina/análogos & derivados , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Encéfalo/metabolismo , Calibragem , Camptotecina/administração & dosagem , Camptotecina/farmacocinética , Feminino , Injeções Intraperitoneais , Irinotecano , Limite de Detecção , Camundongos , Reprodutibilidade dos Testes , Manejo de Espécimes/métodos , Distribuição Tecidual , Sulfato de Zinco/química
16.
J Alzheimers Dis ; 30(1): 155-66, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22391220

RESUMO

The accumulation of amyloid-ß peptide (Aß) in the brain is a critical hallmark of Alzheimer's disease. This high cerebral Aß concentration may be partly caused by impaired clearance of Aß across the blood-brain barrier (BBB). The low-density lipoprotein receptor-related protein-1 (LRP-1) and the ATP-binding cassette (ABC) protein ABCB1 (P-glycoprotein) are involved in the efflux of Aß across the BBB. We hypothesized that other ABC proteins, such as members of the G subfamily, are also involved in the BBB clearance of Aß. We therefore investigated the roles of ABCG2 (BCRP) and ABCG4 in the efflux of [3H] Aß1-40 from HEK293 cells stably transfected with human ABCG2 or mouse abcg4. We showed that ABCG2 and Abcg4 mediate the cellular efflux of [3H] Aß1-40. In addition, probucol fully inhibited the efflux of [3H] Aß1-40 from HEK293-abcg4 cells. Using the in situ brain perfusion technique, we showed that GF120918 (dual inhibitor of Abcb1 and Abcg2) strongly enhanced the uptake (Clup, µl/g/s) of [3H] Aß1-40 by the brains of Abcb1-deficient mice, but not by the brains of Abcb1/Abcg2-deficient mice, suggesting that Abcg2 is involved in the transport of Aß at the mouse BBB. Perfusing the brains of Abcb1/Abcg2- and Abca1-deficient mice with [3H] Aß1-40 plus probucol significantly increased the Clup of Aß. This suggests that a probucol-sensitive transporter that is different from Abca1, Abcb1, and Abcg2 is involved in the brain efflux of Aß. We suggest that this probucol-sensitive transporter is Abcg4. We conclude that Abcg4 acts in concert with Abcg2 to efflux Aß from the brain across the BBB.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Peptídeos beta-Amiloides/metabolismo , Barreira Hematoencefálica/metabolismo , Proteínas de Neoplasias/metabolismo , Fragmentos de Peptídeos/metabolismo , Transportador 1 de Cassete de Ligação de ATP , Subfamília G de Transportadores de Cassetes de Ligação de ATP , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Transportadores de Cassetes de Ligação de ATP/genética , Acridinas/farmacologia , Análise de Variância , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Encéfalo/anatomia & histologia , Encéfalo/metabolismo , Isótopos de Carbono/metabolismo , Linhagem Celular Transformada , Glucose/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microvasos/efeitos dos fármacos , Microvasos/metabolismo , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Perfusão , Tetra-Hidroisoquinolinas/farmacologia , Fatores de Tempo , Transfecção , Trítio/metabolismo
17.
Ther Drug Monit ; 34(2): 171-5, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22354159

RESUMO

PURPOSE: The neuraminidase inhibitor oseltamivir is a recommended treatment for influenza A (H1N1) infection. In rare cases, some patients develop influenza-associated multiple organ failures, requiring rescue therapies such as extracorporeal membrane oxygenation (ECMO) or continuous venovenous hemodiafiltration (CVVHDF). This study was designed to evaluate the impact of ECMO and CVVHDF on the pharmacokinetics of oseltamivir carboxylate (OC) in critically ill patients with pandemic (H1N1) influenza treated with oseltamivir. PATIENTS AND METHODS: Seven critically ill patients on venovenous ECMO for severe pandemic (H1N1) influenza associated with acute respiratory distress syndrome were treated with various doses of oseltamivir (75 or 150 mg twice daily). Because of acute kidney injury, 3 of them also received CVVHDF. OC, the active form of oseltamivir, was quantified in plasma, and main pharmacokinetic parameters were determined. RESULTS: OC Cmax (1029 ± 478 ng/mL) and area under the curve (9.00 ± 4.52 mcg·h/mL) for patients on ECMO with preserved renal function were comparable with those of healthy volunteers or noncritically ill patients. Patients both on ECMO and CVVHDF had 4-to 5-fold higher OC Cmax and area under the curve. CONCLUSIONS: ECMO by itself did not impact on the pharmacokinetics of OC. However, the drug accumulated in the plasma of patients on ECMO who also received CVVHDF for renal failure. Based on these results, we recommend that oseltamivir dosage should be decreased and plasma levels of OC be monitored in patients receiving CVVHDF because of acute kidney injury.


Assuntos
Antivirais/farmacocinética , Oxigenação por Membrana Extracorpórea/métodos , Hemodiafiltração/métodos , Oseltamivir/análogos & derivados , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/terapia , Adulto , Antivirais/uso terapêutico , Área Sob a Curva , Estado Terminal , Relação Dose-Resposta a Droga , Feminino , Humanos , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/complicações , Masculino , Oseltamivir/farmacocinética , Oseltamivir/uso terapêutico , Pandemias , Síndrome do Desconforto Respiratório/etiologia , Síndrome do Desconforto Respiratório/terapia , Adulto Jovem
18.
Mol Pharmacol ; 81(3): 319-27, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22108913

RESUMO

The intestinal H(+)/peptide cotransporter 1 (PepT1) plays a major role in nitrogen supply to the body by mediating intestinal absorption of di- and tripeptides. Previous studies have reported that in animal models of type 2 diabetes/obesity, PepT1 activity and expression were markedly reduced. This prompted us to investigate the effects of two antidiabetic drugs, rosiglitazone and metformin, on PepT1 activity/expression in a murine diet-induced obesity model. C57BL/6J male mice were fed a high-fat diet (HFD) or a standard chow for 6 weeks and then were treated for 7 days with metformin (250 mg/kg/day) and/or rosiglitazone (8 mg/kg/day). For in vitro studies, Caco-2 enterocyte-like cells were treated for 7 days with metformin (10 mM) and/or rosiglitazone (10 µM). A 7-day rosiglitazone treatment increased PepT1 activity and prevented the 2-fold HFD-induced reduction in PepT1 transport. Metformin alone did not modify PepT1 activity but counteracted rosiglitazone-induced PepT1-mediated transport. As with the in vivo studies, rosiglitazone treatment up-regulated PepT1 transport activity with concomitant induction of S6 ribosomal protein activation in vitro. Furthermore, metformin decreased PepT1 expression (mRNA and protein) and its transport activity. The effect of metformin was linked to a reduction of phosphorylated S6 ribosomal protein (active form) and of phosphorylated 4E-BP1 (inactive form), a translation repressor. These data demonstrate that two antidiabetic drugs exert opposite effects on the PepT1 transport function probably through direct action on enterocytes. In our type 2 diabetes/obesity model, rosiglitazone, a peroxisome proliferator-activated receptor-γ agonist compensated for the HFD-induced PepT1 down-regulation, whereas metformin reversed rosiglitazone activity at the translational level.


Assuntos
Hipoglicemiantes/farmacologia , Absorção Intestinal/efeitos dos fármacos , Metformina/farmacologia , Oligopeptídeos/metabolismo , Simportadores/metabolismo , Tiazolidinedionas/farmacologia , Adenilato Quinase/metabolismo , Animais , Sequência de Bases , Células CACO-2 , Primers do DNA , Ativação Enzimática , Ensaio de Imunoadsorção Enzimática , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transportador 1 de Peptídeos , Prótons , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rosiglitazona
19.
Therapie ; 66(5): 405-12, 2011.
Artigo em Francês | MEDLINE | ID: mdl-22031684

RESUMO

Extracorporeal membrane oxygenation (ECMO) is a life support system used in the treatment of patients of all ages with severe respiratory or cardiorespiratory failure. Despite the intensive use of drugs in the treatment of patients on ECMO, few studies have been conducted to determine the impact of this device on the pharmacokinetics of drugs. Publications in this field have shown pharmacokinetics changes resulting in an increase in volume of distribution of drugs and/or decreased clearance with consequent increase of their half-life. Reduced plasma concentrations of some drugs due to their adsorption on the different components of the circuit further complicates the determination of pharmacokinetic parameters of patients treated by ECMO. The literature published up to now on the pharmacokinetic changes associated with ECMO provide preliminary support for dosage adjustment. However, more research is needed to identify dosage strategies for this patient population.


Assuntos
Oxigenação por Membrana Extracorpórea , Farmacocinética , Absorção , Oxigenação por Membrana Extracorpórea/efeitos adversos , Meia-Vida , Humanos , Preparações Farmacêuticas/administração & dosagem , Preparações Farmacêuticas/química , Preparações Farmacêuticas/metabolismo
20.
Mol Cell Biochem ; 357(1-2): 397-404, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21660464

RESUMO

We investigated the expression and function of Abca1 in wild-type C57BL/6, abca1(+/+), and abca1(-/-) mice brain capillaries forming the blood-brain barrier (BBB). We first demonstrated by quantitative RT-PCR and Western immunoblot that Abca1 was expressed and enriched in the wild-type mouse brain capillaries. In abca1(-/-) mice, we reported that the lack of Abca1 resulted in an 1.6-fold increase of the Abcg4 expression level compared to abca1(+/+) mice. Next, using the in situ brain perfusion technique, we showed that the [(3)H]cholesterol brain uptake clearance (Cl(up), µl/s/g brain), was significantly increased (107%) in abca1(-/-) mice compared to abca1(+/+) mice, meaning that the deficiency of Abca1 conducted to a significant decrease of the cholesterol efflux at the BBB level. In addition, the co-perfusion of probucol (Abca1 inhibitor) with [(3)H]cholesterol resulted in an increase of [(3)H]cholesterol Cl(up) (115%) in abca1(+/+) but not in abca1(-/-) mice, meaning that probucol inhibited selectively the efflux function of Abca1. In conclusion, our results demonstrated that Abca1 was expressed in the mouse brain capillaries and that Abca1 functions as an efflux transporter through the mouse BBB.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Barreira Hematoencefálica/metabolismo , Colesterol/metabolismo , Transportador 1 de Cassete de Ligação de ATP , Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/efeitos dos fármacos , Animais , Encéfalo/metabolismo , Encéfalo/cirurgia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Probucol/farmacologia
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