Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 22
Filtrar
1.
Sci Rep ; 11(1): 9587, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33953226

RESUMO

In hepatocellular carcinoma (HCC), blood platelets have been linked to tumor growth, epithelial-to-mesenchymal transition (EMT), extrahepatic metastasis and a limited therapeutic response to the multikinase inhibitor (MKi) sorafenib, the standard of care in advanced HCC for the last decade. Recent clinical data indicated an improved overall survival for sorafenib in combination with the HDAC inhibitor resminostat in a platelet count dependent manner. Here, the impact of platelets on the sorafenib and resminostat drug effects in HCC cells was explored. In contrast to sorafenib, resminostat triggered an anti-proliferative response in HCC cell lines independent of platelets. As previously described, platelets induced invasive capabilities of HCC cells, a prerequisite for extravasation and metastasis. Importantly, the resminostat/sorafenib drug combination, but not the individual drugs, effectively blocked platelet-induced HCC cell invasion. Exploration of the molecular mechanism revealed that the combined drug action led to a reduction of platelet-induced CD44 expression and to the deregulation of several other epithelial and mesenchymal genes, suggesting interference with cell invasion via EMT. In addition, the drug combination decreased phosphorylated ERK level, indicating inhibition of the mitogenic signaling pathway MEK/ERK. Taken together, the resminostat plus sorafenib combination counteracts platelet-mediated cancer promoting effects in HCC cells.


Assuntos
Antineoplásicos/farmacologia , Plaquetas/efeitos dos fármacos , Carcinoma Hepatocelular/patologia , Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , Neoplasias Hepáticas/patologia , Sorafenibe/farmacologia , Sulfonamidas/farmacologia , Animais , Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Quimioterapia Combinada , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Inibidores de Histona Desacetilases/uso terapêutico , Humanos , Ácidos Hidroxâmicos/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Camundongos , Transdução de Sinais/efeitos dos fármacos , Sorafenibe/uso terapêutico , Sulfonamidas/uso terapêutico
2.
J Immunother Cancer ; 7(1): 294, 2019 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-31703604

RESUMO

BACKGROUND: The efficacy of PD-(L)1 blockade depends on the composition of the tumor immune microenvironment (TIME) and is generally higher in tumors with pre-existing cytotoxic T cells (CTL) than in those with low CTL numbers. Nonetheless, a significant proportion of patients with pre-existing immunity fail to respond, indicating a therapeutic potential for combining PD-(L)1 blockade with additional immunomodulatory agents in both CTL-high and -low immune phenotypes. Here, we evaluated domatinostat (4SC-202), a class I-selective histone deacetylase (HDAC) inhibitor, for its effect on the TIME and its antitumoral efficacy using syngeneic mouse models with CTL-high or CTL-low tumors. METHODS: Domatinostat was evaluated in PD-1 blockade-insensitive CTL-low (CT26) and CTL-high (C38) syngeneic models alone and in combination with different immune-inhibitory and -stimulatory approaches. Effects on the immunophenotype were assessed via flow cytometry and RNA-seq analyses. The changes in RNA-seq-based immune signatures determined in a murine setting were investigated in patient samples from the first-dose cohort of the SENSITIZE trial (NCT03278665) evaluating domatinostat combined with pembrolizumab in advanced-stage melanoma patients refractory/nonresponding to PD-1 blockade. RESULTS: Domatinostat increased the expression of antigen-presenting machinery (APM) genes and MHC class I and II molecules, along with CTL infiltration, in tumors of both immune phenotypes. In combination with PD-(L)1 blockade, domatinostat augmented antitumor effects substantially above the effects of single-agent therapies, displaying greater benefit in tumors with pre-existing CTLs. In this setting, the combination of domatinostat with agonistic anti-4-1BB or both PD-1 and LAG3 blockade further increased the antitumor efficacy. In CTL-low tumors, domatinostat enhanced the expression of genes known to reinforce immune responses against tumors. Specifically, domatinostat increased the expression of Ifng and genes associated with responses to pembrolizumab and nivolumab. Clinically, these findings were confirmed in patients with advanced melanoma treated with domatinostat for 14 days, who demonstrated elevated expression of APM and MHC genes, the IFNG gene, and the IFN-γ and pembrolizumab response signatures in individual tumor samples. CONCLUSION: In summary, these data suggest a promising potential of domatinostat in combination with immunotherapy to improve the outcome of refractory cancer patients.


Assuntos
Benzamidas/farmacologia , Neoplasias/imunologia , Neoplasias/patologia , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia , Animais , Apresentação de Antígeno/imunologia , Antígenos de Neoplasias/imunologia , Antineoplásicos Imunológicos/farmacologia , Biomarcadores Tumorais , Biópsia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Inibidores de Histona Desacetilases/farmacologia , Humanos , Imunofenotipagem , Masculino , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Eur J Haematol ; 102(2): 163-173, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30347469

RESUMO

OBJECTIVES: Domatinostat (4SC-202) is a selective class I histone deacetylase inhibitor (HDACi). This phase I study investigated safety, tolerability, pharmacokinetics (PK), pharmacodynamics, and antitumor activity in patients with advanced hematological malignancies. METHODS: Domatinostat was administered orally once (QD) or twice daily (BID) on days 1-14 with 7 days off or continuously days 1-21 in a 3 + 3 design at 7 dose levels from 25 to 400 mg total daily dose (TDD). Twenty-four patients were treated with domatinostat. RESULTS: No formal maximum tolerated dose (MTD) was determined. One dose-limiting toxicity (DLT, grade 4 hypercalcemia) occurred during 200 mg BID continuous treatment. Six patients were reported with ≥ grade 3 treatment-related adverse events (TRAE; grade 3 hematological in three patients, grade 3 and grade 4 liver enzyme increase in 2 patients, grade 4 pulmonary embolism, and grade 4 hypercalcemia in one patient each). Higher grade hepatic TRAE occurred in the 200 mg BID continuous treatment cohort. Out of 24 patients, 1 achieved a complete response, 1 achieved a partial response, and 18 had stable disease as best response. CONCLUSION: Administration of domatinostat was safe, well tolerated with signs of antitumor activity. Four hundred milligram TDD in a 200 mg BID schedule (14 + 7) is the recommended phase II dose for monotherapy.


Assuntos
Benzamidas/uso terapêutico , Neoplasias Hematológicas/tratamento farmacológico , Inibidores de Histona Desacetilases/uso terapêutico , Benzamidas/administração & dosagem , Benzamidas/efeitos adversos , Benzamidas/farmacocinética , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Esquema de Medicação , Avaliação Pré-Clínica de Medicamentos , Feminino , Neoplasias Hematológicas/diagnóstico , Neoplasias Hematológicas/mortalidade , Inibidores de Histona Desacetilases/administração & dosagem , Inibidores de Histona Desacetilases/efeitos adversos , Inibidores de Histona Desacetilases/farmacocinética , Humanos , Masculino , Metástase Neoplásica , Estadiamento de Neoplasias , Tomografia Computadorizada por Raios X , Resultado do Tratamento
4.
J Cancer Res Clin Oncol ; 144(6): 1197-1204, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29644408

RESUMO

PURPOSE: The old approach of one therapeutic for all patients with mCRC is evolving with a need to target specific molecular aberrations or cell-signalling pathways. Molecular screening approaches and new biomarkers are required to fully characterize tumours, identify patients most likely to benefit, and predict treatment response. METHODS: MODUL is a signal-seeking trial with a design that is highly adaptable, permitting modification of different treatment cohorts and inclusion of further additional cohorts based on novel evidence on new compounds/combinations that emerge during the study. RESULTS: MODUL is ongoing and its adaptable nature permits timely and efficient recruitment of patients into the most appropriate cohort. Recruitment will take place over approximately 5 years in Europe, Asia, Africa, and South America. The design of MODUL with ongoing parallel/sequential treatment cohorts means that the overall size and duration of the trial can be modified/prolonged based on accumulation of new data. CONCLUSIONS: The early success of the current trial suggests that the design may provide definitive leads in a patient-friendly and relatively economical trial structure. Along with other biomarker-driven trials that are currently underway, it is hoped that MODUL will contribute to the continuing evolution of clinical trial design and permit a more 'tailored' approach to the treatment of patients with mCRC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Estudos de Coortes , Neoplasias Colorretais/enzimologia , Determinação de Ponto Final , Humanos , Quimioterapia de Indução , Quimioterapia de Manutenção , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Receptor ErbB-2/metabolismo
5.
Target Oncol ; 11(3): 293-308, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26687849

RESUMO

Colorectal cancer is the third most common cancer worldwide. A significant proportion of patients presents with unresectable metastatic disease or develops metachronous metastases following surgical resection of the primary tumor. The prognosis of the disease has improved over the past two decades, with extended multimodality treatment options and the development of increasingly intensified chemotherapy regimens that now typically include targeted biologics. A recent advance in therapy is a treatment regimen composed of three chemotherapeutic agents (i.e., triplet chemotherapy: 5-fluorouracil [5-FU]/leucovorin [LV], oxaliplatin, and irinotecan; FOLFOXIRI) in combination with the vascular endothelial growth factor inhibitor bevacizumab. This regimen has been shown to elicit significantly improved objective response rates and median progression-free survival compared with 5-FU/LV and irinotecan in combination with bevacizumab. However, triplet chemotherapy has been associated with increased rates of chemotherapy-related adverse events, and treatment-emergent adverse events should be properly managed to minimize treatment interruption or discontinuation. We present herein a review of clinical studies evaluating the safety and efficacy of FOLFOXIRI with bevacizumab in metastatic colorectal cancer, and propose a practical guide for the management of adverse events associated with the regimen.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bevacizumab/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Bevacizumab/administração & dosagem , Bevacizumab/farmacologia , Neoplasias Colorretais/patologia , Humanos , Metástase Neoplásica
6.
Oncol Res Treat ; 37(5): 230-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24853781

RESUMO

BACKGROUND: Antiangiogenic therapy is routinely used in a variety of cancer entities. Hypertension is the most common side effect of all currently available antiangiogenic treatments. PATIENTS AND METHODS: In this prospective observational clinical trial, we investigated risk factors for blood pressure elevation in patients exposed to an antiangiogenic agent and explored the correlation between hypertension and the duration of antiangiogenic treatment. RESULTS: In 169 patients, pre-existing antihypertensive medication was the most prominent risk factor associated with increased blood pressure during therapy. Between visits 1 and 3, the median systolic blood pressure increased by 10.85 mmHg in patients with pre-existing hypertension receiving antihypertensive medication while it increased by only 2.69 mmHg in patients without hypertension. The median increase in diastolic pressure was 7.28 versus 0.11 mmHg in patients with versus without pre-existing hypertension. Increases in blood pressure occurred early (within 6 weeks of starting therapy). In spite of this significant increase in the blood pressure, no major bleeding events or other related complications were observed during antiangiogenic therapy. CONCLUSIONS: Pre-existing hypertension and treatment with antihypertensive medication correlated with a more pronounced increase in blood pressure. Thus, intensified antihypertensive therapy might be warranted early during bevacizumab therapy in patients already receiving antihypertensive treatment.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Hipertensão/complicações , Hipertensão/tratamento farmacológico , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Bevacizumab , Pressão Sanguínea/efeitos dos fármacos , Estudos de Coortes , Interações Medicamentosas , Feminino , Humanos , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Neoplasias/fisiopatologia , Estudos Prospectivos , Suíça/epidemiologia , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores
7.
Oncology ; 80(1-2): 29-33, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21606661

RESUMO

OBJECTIVES: While oral anticancer treatment has increased the convenience for patients with no risk of venous access complications compared to intravenous drug administration, a high level of compliance cannot always be assumed. The aim of the present report was to evaluate real-life drug adherence in a prospective cohort analysis of patients with gastrointestinal or breast cancer treated with capecitabine-based chemotherapy. METHODS: Twenty-nine Swiss oncologists recruited patients receiving capecitabine, either as monotherapy or in combination with other chemotherapeutic agents, in a prospective fashion. Patients recorded both their capecitabine intake and any adverse effects each day in patient diaries. RESULTS: A total of 177 patients were included, 143 (81%) with gastrointestinal tumours and 34 (19%) with breast cancer. Overall, 161 patients (91%) were considered as fully compliant, while 16 patients (9%) reported some kind of compliance error. Reasons for non-compliance included forgetting to take treatment (n = 9), side effects (n = 4) and misunderstanding instructions (n = 3). Self-reported compliance was not influenced by age or Eastern Cooperative Oncology Group performance status, but there was a trend towards better compliance with capecitabine therapy if fewer adverse effects occurred (p = 0.07, simple logistic regression). CONCLUSIONS: Self-reported compliance with capecitabine-based therapy in clinical practice is high and seems to be adversely affected by side effects.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Desoxicitidina/análogos & derivados , Fluoruracila/análogos & derivados , Neoplasias Gastrointestinais/tratamento farmacológico , Cooperação do Paciente , Idoso , Antimetabólitos Antineoplásicos/efeitos adversos , Capecitabina , Desoxicitidina/efeitos adversos , Desoxicitidina/uso terapêutico , Diarreia/induzido quimicamente , Feminino , Fluoruracila/efeitos adversos , Fluoruracila/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Estudos Prospectivos , Autorrelato , Estomatite/induzido quimicamente , Vômito/induzido quimicamente
8.
Thromb Res ; 123(3): 460-5, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-18789492

RESUMO

INTRODUCTION: While elevated plasma HDL levels are inversely correlated with cardiovascular events, raising HDL with the CETP inhibitor torcetrapib, however, was associated with increased cardiovascular morbidity and mortality in the ILLUMINATE trial. Whether the deleterious clinical effects of torcetrapib represent a molecule specific off-target effect, a class effect of CETP inhibitors or both is matter of ongoing debate. As such, the aim of the present study was to investigate whether CETP-inhibition with JTT-705, a molecule distinctly different from torcetrapib, impacts on vascular function, a well-established surrogate of atherosclerotic vascular disease, as well as markers of inflammation and oxidative stress in patients with type II hyperlipidemia. METHODS AND RESULTS: Eighteen patients were randomized to receive JTT-705 600 mg/d or matching placebo for 4 weeks. Flow-mediated dilation (FMD) was measured using ultrasonography of the brachial artery. HDL-C increased by 26% from 1.14 mmol/l to 1.44 mmol/l (p=0.01) in the JTT-705 group, while triglycerides decreased from 2.52 mmol/l to 1.97 mmol/l (p=0.03). CETP- inhibition with JTT-705, however, did not change FMD (3.1+/-0.6% to 3.6+/-0.4%; p=0.48). Interestingly, in a sub group analysis of patients with lower than median HDL-C (<1.19 mmol/l), FMD increased by 41% in patients vs. patients with higher than median HDL-C (>1.19 mmol/l; p=0.01). Markers of vascular inflammation (CRP, ICAM-1, IL-6, TNF alpha), as well as plasma endothelin-1 levels all remained unchanged throughout the study. CONCLUSION: In patients with type II hyperlipidemia, CETP inhibition with JTT-705 increased HDL-C and lowered triglycerides but improved endothelial function in the subgroup of patients with low baseline HDL-C levels only.


Assuntos
Anticolesterolemiantes/uso terapêutico , Proteínas de Transferência de Ésteres de Colesterol/antagonistas & inibidores , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Compostos de Sulfidrila/uso terapêutico , Amidas , Pressão Sanguínea/efeitos dos fármacos , HDL-Colesterol/sangue , Método Duplo-Cego , Ésteres , Feminino , Humanos , Hiperlipoproteinemia Tipo II/sangue , Hiperlipoproteinemia Tipo II/fisiopatologia , Masculino , Pessoa de Meia-Idade , Triglicerídeos/sangue
9.
Circulation ; 117(17): 2262-9, 2008 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-18427133

RESUMO

BACKGROUND: The excess in cardiovascular risk in patients with rheumatoid arthritis provides a strong rationale for early therapeutical interventions. In view of the similarities between atherosclerosis and rheumatoid arthritis and the proven benefit of angiotensin-converting enzyme inhibitors in atherosclerotic vascular disease, it was the aim of the present study to delineate the impact of ramipril on endothelial function as well as on markers of inflammation and oxidative stress in patients with rheumatoid arthritis. METHODS AND RESULTS: Eleven patients with rheumatoid arthritis were included in this randomized, double-blind, crossover study to receive ramipril in an uptitration design (2.5 to 10 mg) for 8 weeks followed by placebo, or vice versa, on top of standard antiinflammatory therapy. Endothelial function assessed by flow-mediated dilation of the brachial artery, markers of inflammation and oxidative stress, and disease activity were investigated at baseline and after each treatment period. Endothelial function assessed by flow-mediated dilation increased from 2.85+/-1.49% to 4.00+/-1.81% (P=0.017) after 8 weeks of therapy with ramipril but did not change with placebo (from 2.85+/-1.49% to 2.84+/-2.47%; P=0.88). Although systolic blood pressure and heart rate remained unaltered, diastolic blood pressure decreased slightly from 78+/-7 to 74+/-6 mm Hg (P=0.03). Tumor necrosis factor-alpha showed a significant inverse correlation with flow-mediated dilation (r=-0.408, P=0.02), and CD40 significantly decreased after ramipril therapy (P=0.049). CONCLUSIONS: Angiotensin-converting enzyme inhibition with 10 mg/d ramipril for 8 weeks on top of current antiinflammatory treatment markedly improved endothelial function in patients with rheumatoid arthritis. This finding suggests that angiotensin-converting enzyme inhibition may provide a novel strategy to prevent cardiovascular events in these patients.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Artrite Reumatoide/complicações , Aterosclerose/prevenção & controle , Ramipril/administração & dosagem , Vasculite/prevenção & controle , Adulto , Idoso , Artrite Reumatoide/epidemiologia , Aterosclerose/epidemiologia , Biomarcadores , Células Cultivadas , Estudos Cross-Over , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Estresse Oxidativo/efeitos dos fármacos , Sistema Renina-Angiotensina/efeitos dos fármacos , Fatores de Risco , Resultado do Tratamento , Veias Umbilicais/citologia , Vasculite/epidemiologia , Vasodilatação/efeitos dos fármacos
10.
Int J Cardiol ; 129(1): 141-3, 2008 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-17720264

RESUMO

Sleep apnoea syndrome is frequent in patients with heart failure and associated with a worse prognosis. We evaluated a new device (Auricall) for non-invasive, continuous recording of oxygen saturation (SpO(2)) and heart rate (HR) in patients with heart failure. We studied 20 patients (mean age 48.43+/-14.4 years, NYHA class II-III). All patients were requested to carry the device for at least 36 h and to write a diary during the recording time. Satisfactory recording of SpO(2) and HR was possible to obtain in 18 of 20 patients. Indeed 9 out of 18 patients showed significant periodic changes in SpO(2) during sleep. Therefore, Auricall is a useful tool to non-invasively monitor SpO(2) and HR in patients with heart failure and to detect breathing disorders in these patients.


Assuntos
Insuficiência Cardíaca/metabolismo , Frequência Cardíaca/fisiologia , Monitorização Ambulatorial/instrumentação , Monitorização Ambulatorial/tendências , Consumo de Oxigênio/fisiologia , Adulto , Feminino , Insuficiência Cardíaca/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Ambulatorial/métodos , Oximetria/instrumentação , Oximetria/métodos , Síndromes da Apneia do Sono/diagnóstico , Síndromes da Apneia do Sono/metabolismo
11.
Circulation ; 116(21): 2376-82, 2007 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-17984375

RESUMO

BACKGROUND: Dark chocolate has potent antioxidant properties. Coronary atherosclerosis is promoted by impaired endothelial function and increased platelet activation. Traditional risk factors, high oxidative stress, and reduced antioxidant defenses play a crucial role in the pathogenesis of atherosclerosis, particularly in transplanted hearts. Thus, flavonoid-rich dark chocolate holds the potential to have a beneficial impact on graft atherosclerosis. METHODS AND RESULTS: We assessed the effect of flavonoid-rich dark chocolate compared with cocoa-free control chocolate on coronary vascular and platelet function in 22 heart transplant recipients in a double-blind, randomized study. Coronary vasomotion was assessed with quantitative coronary angiography and cold pressor testing before and 2 hours after ingestion of 40 g of dark (70% cocoa) chocolate or control chocolate, respectively. Two hours after ingestion of flavonoid-rich dark chocolate, coronary artery diameter was increased significantly (from 2.36+/-0.51 to 2.51+/-0.59 mm, P<0.01), whereas it remained unchanged after control chocolate. Endothelium-dependent coronary vasomotion improved significantly after dark chocolate (4.5+/-11.4% versus -4.3+/-11.7% in the placebo group, P=0.01). Platelet adhesion decreased from 4.9+/-1.1% to 3.8+/-0.8% (P=0.04) in the dark chocolate group but remained unchanged in the control group. CONCLUSIONS: Dark chocolate induces coronary vasodilation, improves coronary vascular function, and decreases platelet adhesion 2 hours after consumption. These immediate beneficial effects were paralleled by a significant reduction of serum oxidative stress and were positively correlated with changes in serum epicatechin concentration.


Assuntos
Plaquetas/efeitos dos fármacos , Cacau , Doces , Vasos Coronários/efeitos dos fármacos , Adesividade Plaquetária/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Plaquetas/fisiologia , Angiografia Coronária/métodos , Vasos Coronários/fisiologia , Método Duplo-Cego , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiologia , Flavonoides/administração & dosagem , Transplante de Coração/métodos , Humanos , Adesividade Plaquetária/fisiologia , Vasodilatação/fisiologia , Sistema Vasomotor/efeitos dos fármacos , Sistema Vasomotor/fisiopatologia
12.
J Hypertens ; 25(4): 785-91, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17351370

RESUMO

OBJECTIVE: It has been shown that angiotensin-converting enzyme inhibition or angiotensin receptor blockade may improve endothelial dysfunction, an early manifestation of atherosclerosis, in patients with diabetes. Whether this protective effect is mediated through blood pressure-lowering effects or other specific mechanisms such as a reduction in oxidative stress is not clear. We investigated the influence of losartan, compared with atenolol, on endothelial function and oxidative stress in patients with type 2 diabetes and hypertension. METHODS: Thirteen patients were included in this randomized, double-blind, crossover study; they received losartan 50 mg twice daily for 4 weeks followed by atenolol 50 mg twice daily or vice versa. Concomitant medication with renin-angiotensin blocking agents or beta-blockers was withdrawn, whereas other medication remained unchanged. At baseline and after each treatment period, flow-mediated dilation of the brachial artery and oxidative stress were measured in serum samples. RESULTS: Flow-mediated dilation was increased significantly after 4 weeks' treatment with losartan (3.4 +/- 0.44%) compared with atenolol (2.58 +/- 0.42%; P = 0.01). 8-Isoprostanes, a marker of oxidative stress, were significantly reduced in the losartan group compared with baseline (0.039 +/- 0.007 versus 0.067 +/- 0.006 ng/ml; P = 0.01), but did not differ from baseline with atenolol. Glucose, hemoglobin A1c, highly sensitive C-reactive protein, lipids and systolic blood pressure remained unaltered, whereas diastolic blood pressure tended to be lower in the atenolol group. CONCLUSIONS: This study demonstrates that losartan significantly improved endothelial function in type 2 diabetes patients with hypertension compared with atenolol. This must be independent of the blood pressure-lowering effect of losartan and is probably caused by an antioxidative effect of the angiotensin receptor blocker.


Assuntos
Anti-Hipertensivos/uso terapêutico , Atenolol/uso terapêutico , Diabetes Mellitus Tipo 2/fisiopatologia , Endotélio Vascular/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Losartan/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Artéria Braquial/efeitos dos fármacos , Artéria Braquial/fisiopatologia , Estudos Cross-Over , Diabetes Mellitus Tipo 2/metabolismo , Dinoprosta/análogos & derivados , Dinoprosta/sangue , Método Duplo-Cego , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Feminino , Humanos , Hipertensão/metabolismo , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional/efeitos dos fármacos , Projetos de Pesquisa , Resultado do Tratamento , Vasodilatação/efeitos dos fármacos
13.
J Phys Chem A ; 110(48): 13014-21, 2006 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-17134161

RESUMO

Reactions with delocalized transition states (plateau reactions) can be characterized statically by their energy profile along the reaction path, where they exhibit a broad, flat region instead of one or several well-defined saddle points on the potential energy surface. Employing our new, highly flexible quantum dynamics code to perform two-dimensional and effective four-dimensional quantum wave packet propagations on ab initio based model potentials, we show that plateau reactions can also be discerned from the other standard reaction types by their dynamics.

14.
J Cardiovasc Pharmacol ; 47 Suppl 2: S136-50; discussion S172-6, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16794451

RESUMO

The vascular endothelium synthesizes and releases a spectrum of vasoactive substances and therefore plays a fundamental role in the basal and dynamic regulation of the circulation. Nitric oxide (NO)-originally described as endothelium-derived relaxing factor-is released from endothelial cells in response to shear stress produced by blood flow, and in response to activation of a variety of receptors. After diffusion from endothelial to vascular smooth muscle cells, NO increases intracellular cyclic guanosine-monophosphate concentrations by activation of the enzyme guanylate cyclase leading to relaxation of the smooth muscle cells. NO has also antithrombogenic, antiproliferative, leukocyte-adhesion inhibiting effects, and influences myocardial contractility. Endothelium-derived NO-mediated vascular relaxation is impaired in spontaneously hypertensive animals. NO decomposition by free oxygen radicals is a major mechanism of impaired NO bioavailability. The resulting imbalance of endothelium-derived relaxing and contracting substances disturbs the normal function of the vascular endothelium. Endothelin acts as the natural counterpart to endothelium-derived NO. Besides its arterial blood pressure rising effect in humans, endothelin-1 induces vascular and myocardial hypertrophy, which are independent risk factors for cardiovascular morbidity and mortality. Current therapeutic strategies concentrate mainly on lowering low-density lipoprotein cholesterol and an impressive reduction in the risk for cardiovascular morbidity and mortality has been achieved. Inflammatory mechanisms play an important role in vascular disease and inflammatory plasma markers correlate with prognosis. The production of reactive oxygen species under pathological conditions may represent an important inflammatory trigger. Novel therapeutic strategies specifically targeting inflammation thus bear great potential for the prevention and treatment of atherosclerotic vascular disease. In this context, the vascular actions of flavanol-rich cocoa, particularly with regard to enhanced NO synthesis and endothelial function observed in humans following consumption, warrants further attention. This review discusses pharmacological and dietary intervention.


Assuntos
Endotélio Vascular/fisiologia , Óxido Nítrico/fisiologia , Antagonistas Adrenérgicos beta/farmacologia , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Arginina/metabolismo , Aterosclerose/fisiopatologia , Biopterinas/análogos & derivados , Biopterinas/farmacologia , Cacau , Bloqueadores dos Canais de Cálcio/farmacologia , Inibidores de Ciclo-Oxigenase/farmacologia , Dislipidemias/fisiopatologia , Endotelina-1/fisiologia , Endotelinas/antagonistas & inibidores , Endotelinas/fisiologia , Endotélio Vascular/efeitos dos fármacos , Flavonoides/farmacologia , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Hipercolesterolemia/fisiopatologia , Lipoproteínas HDL/fisiologia , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo
16.
Immunol Lett ; 93(2-3): 199-204, 2004 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-15158617

RESUMO

BACKGROUND/AIMS: Hepatic Kupffer cells (KC) are major regulators of the immune response to gut-derived bacterial products; uncontrolled activation of KC by bacterial components is of pathogenic relevance in alcoholic hepatitis and septic shock. METHODS: We examined the role of bacterial lipopolysaccharide (LPS), bacterial and autologous HSP60 and bacterial DNA, which are recognized by innate Toll-like receptors, during activation of murine KC. RESULTS: In cultivated KC, autologous HSP60 induced a state of LPS-hyporesponsiveness; bacterial DNA did not mitigate the response to subsequent LPS-challenge in vitro; in contrast, pre-treatment of mice with bacterial DNA even significantly increased serum TNF levels, liver function tests and mortality in a model of LPS-induced hemorrhagic liver failure. CONCLUSION: HSP60 and CpG-DNA differentially modulated the threshold of KC activation by LPS and might therefore contribute to the regulation of inflammatory immunity to gut-derived bacterial compounds.


Assuntos
Chaperonina 60/farmacologia , Células de Kupffer/fisiologia , Lipopolissacarídeos/farmacologia , Ativação de Macrófagos/imunologia , Oligodesoxirribonucleotídeos/farmacologia , Alanina Transaminase/sangue , Animais , Linhagem Celular , Células Cultivadas , Chaperonina 60/fisiologia , Proteínas de Ligação a DNA/genética , Feminino , Galactosamina/farmacologia , Expressão Gênica/genética , Interleucina-6/metabolismo , Células de Kupffer/efeitos dos fármacos , Células de Kupffer/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Falência Hepática/induzido quimicamente , Falência Hepática/prevenção & controle , Ativação de Macrófagos/efeitos dos fármacos , Ativação de Macrófagos/fisiologia , Masculino , Camundongos , Receptores de Superfície Celular/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Receptor 4 Toll-Like , Receptor Toll-Like 9 , Fator de Necrose Tumoral alfa/análise , Fator de Necrose Tumoral alfa/metabolismo
20.
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...