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1.
Mol Pharmacol ; 74(1): 144-53, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18413661

RESUMO

Multiple intracellular signaling pathways stimulate quiescent smooth muscle cells (SMCs) to exit from G(0) and re-enter the cell cycle. Thus, a combination of two drugs with different mechanisms of action may represent a suitable approach to control SMC proliferation, a prominent feature of in-stent restenosis. In the present study, we investigated the effect of everolimus, a mammalian target of rapamycin inhibitor, in combination with fluvastatin, a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, on proliferation of rat SMCs. The antiproliferative action of everolimus was amplified by 2.5-fold by the addition of subliminal concentrations of fluvastatin (5 x 10(-7) M), lowering the IC(50) value from 2.5 x 10(-9) to 1.0 x 10(-9) M. The increased antiproliferative effect of everolimus by fluvastatin was prevented in the presence of mevalonate, farnesol, or geranylgeraniol, suggesting the involvement of prenylated proteins. Cell cycle analysis and [3H]thymidine incorporation assay demonstrated that the two drugs synergistically interfered with the progression of G(1) phase. In particular, the drug combination significantly up-regulated p27(Kip1) levels by 47.0%, suppressed cyclin E by 43.0%, and it reduced retinoblastoma (Rb) hyperphosphorylation by 79.0%, compared with everolimus alone. Retroviral overexpression of cyclin E conferred a significant resistance of rat SMCs to the antiproliferative action of the drug combination, measured by cell counting, [3H]thymidine incorporation, and cell cycle analysis, with higher levels of hyperphosphorylated form of Rb. Taken together, these results demonstrated that everolimus acts synergistically with fluvastatin to inhibit SMC proliferation by altering the expression of cyclin E and p27(kip1), which affects Rb phosphorylation and leads to G(1) phase arrest.


Assuntos
Proliferação de Células/efeitos dos fármacos , Ciclina E/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Ácidos Graxos Monoinsaturados/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Indóis/farmacologia , Músculo Liso Vascular/citologia , Sirolimo/análogos & derivados , Animais , Ciclina E/genética , Inibidor de Quinase Dependente de Ciclina p27/genética , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Everolimo , Fluvastatina , Fase G1 , Concentração Inibidora 50 , Músculo Liso Vascular/efeitos dos fármacos , Ratos , Sirolimo/farmacologia
2.
Laryngoscope ; 115(10): 1793-9, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16222197

RESUMO

OBJECTIVES: To evaluate antifungal terbinafine in patients with chronic rhinosinusitis. STUDY DESIGN: Randomized, double-blind, placebo-controlled multicenter pilot study. METHODS: Fifty-three adults with chronic rhinosinusitis received terbinafine 625 mg/day (n = 25) or placebo (n = 28) once daily for 6 weeks. Sinus secretions were collected at screening for mycology. Computed tomography was graded for extent of opacification at baseline and at week 6 using a modification of the Lund-Mackay scoring system. Patients recorded rhinosinusitis symptoms on a visual analogue scale and completed the Rhinosinusitis Disability Index. RESULTS: Positive fungal cultures were found in 41 of 53 patients (17 terbinafine, 24 placebo). (Two subjects from the Terbinafine group and one subject from the control group had no week 6 data). The mean opacification scores pre- and posttreatment for the entire study group improved from 24.2 to 22.5 in placebo (n = 26) and from 26.3 to 24.2 in terbinafine group (n = 23). The least squares means for percent change from baseline (SE) were -6.0 (8.7) for placebo compared with -7.2 (8.1) for terbinafine; 95% confidence interval for treatment difference (-18.9, 21.1); P = .91. Results were similar when only patients with positive fungal cultures were evaluated in the efficacy analysis. Investigator therapeutic evaluations and sinus symptom scores were not significantly different between the two groups at baseline or at treatment completion. CONCLUSION: Treatment with terbinafine failed to improve the symptoms or radiographic appearance of chronic rhinosinusitis even when nasal irrigation samples were positive for fungus on culture. One consideration is that the fungi isolated were not a major pathologic factor in this cohort. It is also possible that, even at high dose, terbinafine may not have maintained therapeutic levels in the nasal secretions.


Assuntos
Antifúngicos/administração & dosagem , Micoses/tratamento farmacológico , Naftalenos/administração & dosagem , Rinite/tratamento farmacológico , Sinusite/tratamento farmacológico , Administração Oral , Adulto , Doença Crônica , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Terbinafina
3.
Eur Heart J ; 20(1): 58-69, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10075142

RESUMO

BACKGROUND: The 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase inhibitors competitively inhibit biosynthesis of mevalonate, a precursor of non-sterol compounds involved in cell proliferation. Experimental evidence suggests that fluvastatin may, independent of any lipid lowering action, exert a greater direct inhibitory effect on proliferating vascular myocytes than other statins. The FLARE (Fluvastatin Angioplasty Restenosis) Trial was conceived to evaluate the ability of fluvastatin 40 mg twice daily to reduce restenosis after successful coronary balloon angioplasty (PTCA). METHODS: Patients were randomized to either placebo or fluvastatin 40 mg twice daily beginning 2-4 weeks prior to planned PTCA and continuing after a successful PTCA (without the use of a stent), to follow-up angiography at 26+/-2 weeks. Clinical follow-up was completed at 40 weeks. The primary end-point was angiographic restenosis, measured by quantitative coronary angiography at a core laboratory, as the loss in minimal luminal diameter during follow-up. Clinical end-points were death, myocardial infarction, coronary artery bypass graft surgery or re-intervention, up to 40 weeks after PTCA. RESULTS: Of 1054 patients randomized, 526 were allocated to fluvastatin and 528 to placebo. Among these, 409 in the fluvastatin group and 427 in the placebo group were included in the intention-to-treat analysis, having undergone a successful PTCA after a minimum of 2 weeks of pre-treatment. At the time of PTCA, fluvastatin had reduced LDL cholesterol by 37% and this was maintained at 33% at 26 weeks. There was no difference in the primary end-point between the treatment groups (fluvastatin 0.23+/-0.49 mm vs placebo 0.23+/-0.52 mm, P=0.95) or in the angiographic restenosis rate (fluvastatin 28%, placebo 31%, chi-square P=0.42), or in the incidence of the composite clinical end-point at 40 weeks (22.4% vs 23.3%; logrank P=0.74). However, a significantly lower incidence of total death and myocardial infarction was observed in six patients (1.4%) in the fluvastatin group and 17 (4.0%) in the placebo group (log rank P=0.025). CONCLUSION: Treatment with fluvastatin 80 mg daily did not affect the process of restenosis and is therefore not indicated for this purpose. However, the observed reduction in mortality and myocardial infarction 40 weeks after PTCA in the fluvastatin treated group has not been previously reported with statin therapy. Accordingly, a priori investigation of this finding is indicated and a new clinical trial with this intention is already underway.


Assuntos
Angioplastia Coronária com Balão , Doença das Coronárias/terapia , Ácidos Graxos Monoinsaturados/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Indóis/uso terapêutico , Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/mortalidade , Método Duplo-Cego , Feminino , Fluvastatina , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/prevenção & controle , Estudos Retrospectivos , Prevenção Secundária , Taxa de Sobrevida , Resultado do Tratamento
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