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1.
Nat Cancer ; 4(1): 96-107, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36581734

RESUMO

Patients with cancer are at high risk of severe coronavirus disease 2019 (COVID-19), with high morbidity and mortality. Furthermore, impaired humoral response renders severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines less effective and treatment options are scarce. Randomized trials using convalescent plasma are missing for high-risk patients. Here, we performed a randomized, open-label, multicenter trial ( https://www.clinicaltrialsregister.eu/ctr-search/trial/2020-001632-10/DE ) in hospitalized patients with severe COVID-19 (n = 134) within four risk groups ((1) cancer (n = 56); (2) immunosuppression (n = 16); (3) laboratory-based risk factors (n = 36); and (4) advanced age (n = 26)) randomized to standard of care (control arm) or standard of care plus convalescent/vaccinated anti-SARS-CoV-2 plasma (plasma arm). No serious adverse events were observed related to the plasma treatment. Clinical improvement as the primary outcome was assessed using a seven-point ordinal scale. Secondary outcomes were time to discharge and overall survival. For the four groups combined, those receiving plasma did not improve clinically compared with those in the control arm (hazard ratio (HR) = 1.29; P = 0.205). However, patients with cancer experienced a shortened median time to improvement (HR = 2.50; P = 0.003) and superior survival with plasma treatment versus the control arm (HR = 0.28; P = 0.042). Neutralizing antibody activity increased in the plasma cohort but not in the control cohort of patients with cancer (P = 0.001). Taken together, convalescent/vaccinated plasma may improve COVID-19 outcomes in patients with cancer who are unable to intrinsically generate an adequate immune response.


Assuntos
COVID-19 , Neoplasias , Humanos , COVID-19/terapia , SARS-CoV-2 , Imunização Passiva/efeitos adversos , Resultado do Tratamento , Soroterapia para COVID-19 , Anticorpos Antivirais , Neoplasias/terapia
2.
Wound Repair Regen ; 19(6): 687-92, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22092839

RESUMO

We have previously explored in vitro as well as in vivo models of the biological effects of liquid fibrin glue (FG) containing factor XIII. The fixed combination of a collagen matrix and coagulation factors I and IIa (TachoSil(®) , Nycomed, Linz, Austria) is void of factor XIII. We aimed to determine whether (1) this preparation exerts similar effects to liquid FG on cells in an in vitro system, or (2) this effect is modulated by factor XIII. In an in vitro model, the effect of the fixed combination of collagen matrix and coagulation factors I and IIa (collagen matrix-bound clotting factor [CMBCF]) on the expression and secretion of growth factors (vascular endothelial growth factor, platelet-derived growth factor, fibroblast growth factor-2) by gastric epithelial (AGS) and mesenchymal cells (fibroblasts), as well as their proliferative response (WST-test), was compared in the presence and absence of factor XIII. The use of CMBCF compared with collagen type I matrix resulted in an increased proliferation rate of fibroblasts; there was an increased secretion of fibroblast growth factor-2. Gastric epithelial cells secreted more vascular endothelial growth factor and platelet-derived growth factor into the culture supernatant in the presence of CMBCF. All responses remained unaltered by the addition of factor XIII in different concentrations. In conclusion, CMBCF exerted effects similar to liquid FG in an in vitro model of healing. The addition of factor XIII did not alter the response of mesenchymal or epithelial cells, with respect to proliferation and growth factor secretion.


Assuntos
Fator XIII/farmacologia , Fibrinogênio/farmacologia , Trombina/farmacologia , Cicatrização/efeitos dos fármacos , Coagulação Sanguínea/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Colágeno , Combinação de Medicamentos , Adesivo Tecidual de Fibrina/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/metabolismo , Hemostasia/efeitos dos fármacos , Humanos , Fator de Crescimento Derivado de Plaquetas/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Cicatrização/fisiologia
3.
Eur J Nucl Med Mol Imaging ; 35(10): 1775-85, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18481063

RESUMO

PURPOSE: This prospective single-centre phase II trial assessed the diagnostic impact of (18)F-FDG PET-CT in the evaluation of solid pancreatic lesions (phi >or= 10 mm) compared to endosonography (EUS), endoscopic retrograde cholangio-pancreatography (ERCP) with intraductal ultrasound (IDUS), abdominal ultrasound (US) and histopathological reference. METHODS: Forty-six patients (32 men/14 women, phi 61.7 years) with suspected pancreatic neoplasms underwent PET-CT with contrast-enhanced biphasic multi-detector CT of the upper abdomen followed by a diagnostic work-up with EUS, ERCP with IDUS and US within 3 weeks. PET-CT data sets were analysed by two expert readers in a consensus reading. Histology from surgery, biopsy/fine-needle aspiration and/or clinical follow-up >or=12 months served as standard of reference. RESULTS: Twenty-seven pancreatic malignancies were histopathologically proven; 19 patients had benign diseases: 36/46 lesions (78%) were detected in the head of the pancreas, 7/46 and 3/46 in the body and tail region, respectively. Sensitivity and specificity of PET-CT were 89% and 74%, respectively; positive predictive value (PPV) and negative predictive value (NPV) were 83% and 82%, respectively. Sensitivity (81-89%), specificity (74-88%), PPV (83-90%) and NPV (77-82%) achieved by EUS, ERCP and US were not significantly different. PET analysis revealed significantly higher maximum mean standardised uptake values (SUV(max) 6.5+/-4.6) in patients with pancreatic malignancy (benign lesions: SUV(max) 4.2+/-1.5; p<0.05). PET-CT revealed cervical lymphonodal metastasis from occult bronchogenic carcinoma and a tubular colon adenoma with intermediate dysplasia on polypectomy, respectively. CONCLUSIONS: (18)F-FDG PET-CT achieves a comparably high diagnostic impact evaluating small solid pancreatic lesions versus conventional reference imaging modalities. Additional clinical diagnoses are derived from concomitant whole-body PET-CT imaging.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica , Endoscopia do Sistema Digestório , Fluordesoxiglucose F18 , Neoplasias Pancreáticas/diagnóstico , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Técnica de Subtração
4.
Scand J Gastroenterol ; 42(7): 852-8, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17558910

RESUMO

OBJECTIVE: Heme oxygenase-1 (HO-1) has emerged as a crucial mediator of mucosal defense in the gastrointestinal tract. Its metabolic pathway products, biliverdin/bilirubin and carbon monoxide, can reduce oxidative stress and inflammation, and promote resistance to apoptosis. The role of HO-1 in gastrointestinal malignancies, however, remains to be elucidated. The purpose of this study was to analyze HO-1 expression in human colon adenoma and cancer samples. MATERIAL AND METHODS: Fifty-five paraffin-embedded surgical specimens of colorectal cancer and 19 colonic adenoma samples were stained immunhistochemically for HO-1 expression using an anti-HO-1 monoclonal antibody. HO-1 expression was evaluated independently by two different investigators and subsequently correlated to clinical data and patients' life expectancy. RESULTS: Focal HO-1 expression could be documented in 41.8% (23/55) of patients with colorectal cancer. HO-1 expression in colonic adenoma was detectable in 36.8% (7/19) of cases. The rate of lymphatic tumor invasion was significantly lower in colorectal cancer samples expressing HO-1 (p=0.048). Additionally, fewer lymph node metastases were found in colorectal cancer samples with HO-1 expression, but these differences did not reach statistical significance. Mean observation period was 65.87+/-3.96 months. Kaplan-Meier analysis showed a significantly better survival for colorectal cancer patients with colonic HO-1 expression (p=0.018). CONCLUSIONS: This study demonstrates that colonic HO-1 may be a prognostic marker of colorectal-cancer outcome.


Assuntos
Adenoma/enzimologia , Biomarcadores Tumorais/metabolismo , Colo/enzimologia , Neoplasias Colorretais/enzimologia , Heme Oxigenase-1/metabolismo , Adenoma/mortalidade , Adenoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Feminino , Seguimentos , Humanos , Imuno-Histoquímica , Mucosa Intestinal/enzimologia , Mucosa Intestinal/patologia , Estimativa de Kaplan-Meier , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Fatores de Risco , Taxa de Sobrevida
5.
Biochem Biophys Res Commun ; 345(3): 1014-21, 2006 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-16712795

RESUMO

Proton pump inhibitors (PPIs) have been demonstrated to prevent gastric mucosal injury by mechanisms independent of acid inhibition. Here we demonstrate that both omeprazole and lansoprazole protect human gastric epithelial and endothelial cells against oxidative stress. This effect was abrogated in the presence of the heme oxygenase-1 (HO-1) inhibitor ZnBG. Exposure to either PPI resulted in a strong induction of HO-1 expression on mRNA and protein level, and led to an increased activity of this enzyme. Expression of cyclooxygenase isoforms 1 and 2 remained unaffected, and COX-inhibitors did not antagonize HO-1 induction by PPIs. Our results suggest that the antioxidant defense protein HO-1 is a target of PPIs in both endothelial and gastric epithelial cells. HO-1 induction might account for the gastroprotective effects of PPIs independently of acid inhibition, especially in NSAID gastropathy. Moreover, our findings provide additional perspectives for a possible but yet unexplored use of PPIs in vasoprotection.


Assuntos
Células Endoteliais/metabolismo , Ácido Gástrico/metabolismo , Mucosa Gástrica/metabolismo , Heme Oxigenase-1/biossíntese , 2-Piridinilmetilsulfinilbenzimidazóis , Animais , Linhagem Celular Tumoral , Ciclo-Oxigenase 1/química , Deuteroporfirinas/farmacologia , Inibidores Enzimáticos/farmacologia , Heme Oxigenase-1/antagonistas & inibidores , Humanos , Lansoprazol , Omeprazol/análogos & derivados , Omeprazol/farmacologia , Estresse Oxidativo , Ratos
6.
Am J Gastroenterol ; 101(3): 422-30, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16542275

RESUMO

OBJECTIVES: The aim of this study was to compare and determine the efficiency and safety of two newly introduced endoscopic antireflux procedures in the treatment of gastroesophageal reflux disease (GERD). METHODS: In a prospective, randomized trial, endoluminal gastroplasty (EndoCinch) was compared with polymer injection (Enteryx) employing 51 consecutive patients dependent on proton pump inhibitor therapy. Follow-up evaluation included drug consumption, symptoms, quality-of-life scoring, endoscopy, pH monitoring, manometry, and documentation of adverse events. RESULTS: Twenty-six patients were assigned to EndoCinch treatment, 23 patients received Enteryx implantation, and two patients dropped out before applying endoscopic therapy. At 6 months, proton pump inhibitor therapy could be stopped or dosage was reduced by > or =50% in 20 of 26 (77%) EndoCinch-treated patients and in 20 of 23 patients treated by Enteryx (87%, p= 0.365), which differed significantly in both groups compared to the pre-interventional status (p < 0.0001). Esophageal acid reflux (pH < 4) decreased from 14.5% to 9.6% in EndoCinch-treated patients (p= 0.071) and from 15.5% to 13.9% in patients treated by Enteryx (p= 0.930). Heartburn symptom score, modified DeMeester score, gastrointestinal life quality index, and SF-36 physical health survey score improved significantly in both groups postinterventionally (p < 0.0001). Approximately 25% of the patients in both groups required retreatment in an attempt to achieve symptom control. CONCLUSIONS: This is the first prospective, randomized study directly comparing two endoscopic anti-GERD techniques. EndoCinch and Enteryx seem to be equally successful in the treatment of GERD significantly reducing the proton pump inhibitor dosages, and also by improving symptoms of patients. Both endoluminal antireflux procedures may be promising therapeutic options; long-term evaluation will have to show if the positive initial results can be maintained.


Assuntos
Refluxo Gastroesofágico/cirurgia , Gastroplastia , Gastroscopia , Polivinil , Próteses e Implantes , Adulto , Idoso , Terapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Processos e Resultados em Cuidados de Saúde , Estudos Prospectivos , Inibidores da Bomba de Prótons , Qualidade de Vida
8.
Scand J Gastroenterol ; 40(4): 482-5, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16028445

RESUMO

Tumors of the small intestine are rare as compared to malignant tumors of the pancreas. Here we report on the case of a 61-year-old man suffering from chronic pancreatitis presenting with a lesion projecting into the pancreatic head shown by both computed tomography and transabdominal ultrasound. Pancreatic cancer was suspected, but endoscopic ultrasound revealed this lesion to be situated in the submucosal layer of the duodenal wall. Surgery was performed since biopsy of this lesion was not diagnostic and a malignant leiomyosarcoma could therefore not be excluded. Limited surgery comprised resection of the duodenal lesion, whereas based on computed tomography alone, exploration of the pancreas would have been performed. Thus, in the present case endoscopic ultrasound leads to a more appropriate, less invasive therapeutic measure.


Assuntos
Neoplasias Duodenais/diagnóstico , Endossonografia , Leiomioma/diagnóstico , Neoplasias Pancreáticas/diagnóstico , Diagnóstico Diferencial , Procedimentos Cirúrgicos do Sistema Digestório , Neoplasias Duodenais/cirurgia , Humanos , Leiomioma/cirurgia , Masculino , Pessoa de Meia-Idade
10.
Gastrointest Endosc ; 61(4): 560-7, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15812409

RESUMO

BACKGROUND: Fibrin glue is used in the endoscopic therapy of bleeding ulcerations. Accelerated closure of ulcers has been attributed to this treatment; the biologic reason, however, remains unclear. METHODS: Two artificial gastric lesions were induced in healthy, Helicobacter pylori negative volunteers and were treated by injection of either saline solution or fibrin glue. After 72 hours, resulting ulcers were measured and biopsy specimens were taken for immunohistochemistry (to identify proliferating cells and small vessels) and assessment of growth factor messenger RNA (mRNA) expression (platelet derived growth factor, vascular endothelial growth factor, fibroblast growth factor 2 [FGF-2]) by real-time reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: After 72 hours, most lesions exposed to fibrin glue were smaller than the corresponding ones treated with saline solution. The ulcer rim was more pronounced; immunohistochemistry revealed more proliferating cells (p < 0.02 compared with saline solution). The number of microvessels also increased, though this difference did not reach statistical significance (p = 0.10). FGF-2 mRNA expression markedly increased (about 7-fold compared with the control [ p < 0.001], and about 5-fold compared with saline solution [ p < 0.015]); whereas, with respect to platelet derived growth factor and vascular endothelial growth factor mRNAs, only small changes occurred. CONCLUSIONS: Fibrin glue positively modulates gastric ulcer healing by causing an increase in the number of proliferating cells in the ulcer margin and also possibly enhances the density of microvessels. These changes are accompanied by an enhanced expression of FGF-2, which is known to exert beneficial effects on ulcer healing.


Assuntos
Adesivo Tecidual de Fibrina/administração & dosagem , Substâncias de Crescimento/metabolismo , Hemostáticos/administração & dosagem , Antro Pilórico/metabolismo , Úlcera Gástrica/tratamento farmacológico , Cicatrização/efeitos dos fármacos , Adolescente , Adulto , Feminino , Mucosa Gástrica/lesões , Mucosa Gástrica/metabolismo , Substâncias de Crescimento/genética , Humanos , Injeções Intralesionais , Masculino , Pessoa de Meia-Idade , Antro Pilórico/lesões , RNA Mensageiro/metabolismo , Úlcera Gástrica/metabolismo , Úlcera Gástrica/patologia , Cicatrização/fisiologia
11.
Cancer Res ; 65(5): 1778-82, 2005 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-15753374

RESUMO

Development of distant metastasis after tumor resection is the leading cause of death in early-stage non-small cell lung cancer (NSCLC). Receptor tyrosine kinases (RTK) are involved in tumorigenesis but only few RTKs have been systematically studied in NSCLC. Here, we provide quantitative real-time reverse transcription-PCR expression data of all RTKs (n=56) in primary tumors of 70 patients with early-stage (I-IIIA) NSCLC. Overall, 33 RTKs were expressed in at least 25% of the patients. Several RTKs were significantly expressed higher in tumors that ultimately metastasized. The hazard risk for metastasis development in stage I/II disease was increased at least 3-fold for tumors with high expression levels of insulin receptor, neurotrophic tyrosine receptor kinase 1, epidermal growth factor receptor, ERBB2, ERBB3, platelet-derived growth factor receptor beta, fibroblast growth factor receptor 1, or leukocyte tyrosine kinase. Relative risks were reduced 3-fold by expression of EPHB6 or DKFZ1. Three members of the epidermal growth factor receptor family were associated with a high risk of metastasis, emphasizing the validity of our data. High ERBB3 expression was significantly associated with decreased survival. Taken together, our genome-wide RTK expression map uncovered the previously unknown value of several RTKs as potential markers for prognosis and metastasis prediction in early-stage NSCLC. The identified RTKs represent promising novel candidates for further functional analyses.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Receptores Proteína Tirosina Quinases/genética , Primers do DNA/química , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/metabolismo , Estadiamento de Neoplasias , Prognóstico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
12.
Br J Clin Pharmacol ; 58(6): 587-600, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15563357

RESUMO

Gastrointestinal (GI) toxicity associated with nonsteroidal anti-inflammatory drugs (NSAIDs) is still an important medical and socio-economic problem--despite recent pharmaceutical advances. To prevent NSAID-induced gastropathy, three strategies are followed in clinical routine: (i) coprescription of a gastroprotective drug, (ii) use of selective COX-2 inhibitors, and (iii) eradication of Helicobacter pylori. Proton pump inhibitors are the comedication of choice as they effectively reduce gastrointestinal adverse events of NSAIDs and are safe even in long-term use. Co-medication with vitamin C has only been little studied in the prevention of NSAID-induced gastropathy. Apart from scavenging free radicals it is able to induce haeme-oxgenase 1 in gastric cells, a protective enzyme with antioxidant and vasodilative properties. Final results of the celecoxib outcome study (CLASS study) attenuated the initial enthusiasm about the GI safety of selective COX-2 inhibitors, especially in patients concomitantly taking aspirin for cardiovascular prophylaxis. Helicobacter pylori increases the risk for ulcers particularly in NSAID-naive patients and therefore eradication is recommended prior to long-term NSAID therapy at least in patients at high risk. New classes of COX-inhibitors are currently evaluated in clinical studies with very promising results: NSAIDs combined with a nitric oxide releasing moiety (NO-NSAID) and dual inhibitors of COX and 5-LOX. These drugs offer extended anti-inflammatory potency while sparing gastric mucosa.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Inibidores de Ciclo-Oxigenase/uso terapêutico , Gastroenteropatias/prevenção & controle , Antiácidos/uso terapêutico , Química Farmacêutica , Gastroenteropatias/induzido quimicamente , Infecções por Helicobacter/prevenção & controle , Helicobacter pylori , Antagonistas dos Receptores H2 da Histamina/uso terapêutico , Humanos , Inibidores da Bomba de Prótons
14.
Biochem Biophys Res Commun ; 312(2): 507-12, 2003 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-14637166

RESUMO

Free oxygen radicals contribute to gastric mucosal damage induced by acetylic-salicylic acid (ASA). Vitamin C has been shown to reduce gastric toxicity of ASA in humans. We intended to assess the role of heme oxygenase-1 (HO-1) in this process by application of these substances to AGS and KATO III cells. HO-1 expression was monitored by real-time RT-PCR, Western blot, and HO activity measurement. HO-1 mRNA was significantly elevated by either ASA or vitamin C in gastric epithelial cells, combination of both substances further increased expression. HO-1 protein and enzyme activity rose in cells exposed to vitamin C alone or combined with ASA, but not after stimulation with ASA alone. In contrast to endothelia, in which ASA simultaneously induces HO-1 mRNA and protein expression, gastric epithelial cells require vitamin C to translate HO-1 mRNA into active protein, which then may exert gastroprotection by its antioxidant and vasodilative properties.


Assuntos
Ácido Ascórbico/farmacologia , Aspirina/farmacologia , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/metabolismo , Heme Oxigenase (Desciclizante)/metabolismo , Neoplasias Gástricas/metabolismo , Anti-Inflamatórios não Esteroides/farmacologia , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Interações Medicamentosas , Heme Oxigenase-1 , Humanos , Proteínas de Membrana
15.
Br J Clin Pharmacol ; 56(2): 156-64, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12895188

RESUMO

The function of the stomach includes initiation of digestion by exocrine secretions such as acid and pepsin, which are under the control of the endocrine secretion of hormones that also coordinate intestinal motility. The stomach also stores and mechanically disrupts ingested food. Various techniques have been developed to assess gastric physiology, the most important of which is assessment of acid secretion, as well as gastric motility and gastric emptying. The influence of drugs on gastric function and the effect of gastric secretion and mechanical actions on the bioavailability of novel compounds are of critical importance in drug development and hence to clinical pharmacologists. The control of acid secretion is essential in the treatment of peptic ulcer disease as well as gastrooesophageal reflux disease (GORD); pH-metry can be used to determine the necessary dose of an acid suppressant to heal mucosal damage. Disturbed gastric myoelectric activity leading to gastroparesis can cause delayed gastric emptying, often found in patients with diabetes mellitus. Electrogastrography (EGG) may be used to evaluate the influence of prokinetics and other drugs on this condition and aid in determining effective therapy.


Assuntos
Estômago/fisiologia , Glândulas Endócrinas/fisiologia , Glândulas Exócrinas/fisiologia , Esvaziamento Gástrico , Gastrinas/sangue , Gastrinas/metabolismo , Refluxo Gastroesofágico/tratamento farmacológico , Refluxo Gastroesofágico/fisiopatologia , Gastroparesia/tratamento farmacológico , Gastroparesia/fisiopatologia , Humanos , Concentração de Íons de Hidrogênio
16.
Biochem Biophys Res Commun ; 308(4): 956-60, 2003 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-12927812

RESUMO

Aspirin is known to exert antioxidant effects by as yet unidentified mechanisms. In cultured endothelial cells derived from human umbilical vein, aspirin (30-300 microM) increased heme oxygenase-1 (HO-1) protein levels in a concentration-dependent fashion up to fivefold over basal levels. HO-1 induction was accompanied by a marked increase in catalytic activity of the enzyme as reflected by enhanced formation of both carbon monoxide and bilirubin. Pretreatment with aspirin or bilirubin at low micromolar concentrations protected endothelial cells from hydrogen peroxide-mediated toxicity. HO-1 induction and endothelial protection by aspirin were not mimicked by indomethacin, another inhibitor of cyclooxygenase. The nitric oxide (NO) synthase blocker L-NAME prevented aspirin-dependent HO-1 induction. These findings demonstrate that aspirin targets HO-1, presumably via NO-dependent pathways. Induction of HO-1 expression and activity may be a novel mechanism by which aspirin prevents cellular injury under inflammatory conditions and in cardiovascular disease.


Assuntos
Antioxidantes/farmacologia , Aspirina/farmacologia , Heme Oxigenase (Desciclizante)/metabolismo , Bilirrubina/química , Bilirrubina/metabolismo , Monóxido de Carbono/química , Monóxido de Carbono/metabolismo , Linhagem Celular , Sobrevivência Celular , Células Cultivadas , Inibidores de Ciclo-Oxigenase/metabolismo , Relação Dose-Resposta a Droga , Endotélio Vascular/citologia , Inibidores Enzimáticos/farmacologia , Heme Oxigenase-1 , Humanos , Peróxido de Hidrogênio/farmacologia , Indometacina/metabolismo , Inflamação , Proteínas de Membrana , NG-Nitroarginina Metil Éster/farmacologia , Oxidantes/metabolismo , Veias Umbilicais/citologia
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