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1.
Thorax ; 75(2): 143-152, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31892546

RESUMEN

BACKGROUND: While malignant pleural effusion (MPE) is a common and significant cause of morbidity in patients with cancer, current treatment options are limited. Human heparanase, involved in angiogenesis and metastasis, cleaves heparan sulfate (HS) side chains on the cell surface. AIMS: To explore the coagulation milieu in MPE and infectious pleural effusion (IPE) focusing on the involvement of heparanase. METHODS: Samples of 30 patients with MPE and 44 patients with IPE were evaluated in comparison to those of 33 patients with transudate pleural effusions, using heparanase ELISA, heparanase procoagulant activity assay, thrombin and factor Xa chromogenic assays and thromboelastography. A cell proliferation assay was performed. EMT-6 breast cancer cells were injected to the pleural cavity of mice. A peptide inhibiting heparanase activity was administered subcutaneously. RESULTS: Levels of heparanase, factor Xa and thrombin were significantly higher in exudate than transudate. Thromboelastography detected almost no thrombus formation in the whole blood, mainly on MPE addition. This effect was completely reversed by bacterial heparinase. Direct measurement revealed high levels of HS chains in pleural effusions. Higher proliferation was observed in tumour cell lines incubated with exudate than with transudate and it was reduced when bacterial heparinase was added. The tumour size in the pleural cavity of mice treated with the heparanase inhibitor were significantly smaller compared with control (p=0.005). CONCLUSIONS: HS chains released by heparanase form an anticoagulant milieu in MPE, preventing local thrombosis and enabling tumour cell proliferation. Inhibition of heparanase might provide a therapeutic option for patients with recurrent MPE.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Coagulación Sanguínea/efectos de los fármacos , Glucuronidasa/metabolismo , Heparitina Sulfato/administración & dosificación , Derrame Pleural Maligno/tratamiento farmacológico , Derrame Pleural Maligno/metabolismo , Animales , Anticoagulantes/administración & dosificación , Estudios de Casos y Controles , Proliferación Celular , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunohistoquímica , Masculino , Ratones , Ratones Endogámicos BALB C , Neovascularización Patológica/prevención & control , Valores de Referencia , Estadísticas no Paramétricas , Tromboelastografía/métodos , Trombosis/prevención & control , Células Tumorales Cultivadas
2.
Haematologica ; 95(11): 1927-34, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20634491

RESUMEN

BACKGROUND: Heparanase is an endo-ß-D-glucuronidase dominantly involved in tumor metastasis and angiogenesis. Recently, we demonstrated that heparanase is involved in the regulation of the hemostatic system. Our hypothesis was that heparanase is directly involved in activation of the coagulation cascade. DESIGN AND METHODS: Activated factor X and thrombin were studied using chromogenic assays, immunoblotting and thromboelastography. Heparanase levels were measured by enzyme-linked immunosorbent assay. A potential direct interaction between tissue factor and heparanase was studied by co-immunoprecipitation and far-western assays. RESULTS: Interestingly, addition of heparanase to tissue factor and activated factor VII resulted in a 3- to 4-fold increase in activation of the coagulation cascade as shown by increased activated factor X and thrombin production. Culture medium of human embryonic kidney 293 cells over-expressing heparanase and its derivatives increased activated factor X levels in a non-enzymatic manner. When heparanase was added to pooled normal plasma, a 7- to 8-fold increase in activated factor X level was observed. Subsequently, we searched for clinical data supporting this newly identified role of heparanase. Plasma samples from 35 patients with acute leukemia at presentation and 20 healthy donors were studied for heparanase and activated factor X levels. A strong positive correlation was found between plasma heparanase and activated factor X levels (r=0.735, P=0.001). Unfractionated heparin and an inhibitor of activated factor X abolished the effect of heparanase, while tissue factor pathway inhibitor and tissue factor pathway inhibitor-2 only attenuated the procoagulant effect. Using co-immunoprecipitation and far-western analyses it was shown that heparanase interacts directly with tissue factor. CONCLUSIONS: Overall, our results support the notion that heparanase is a potential modulator of blood hemostasis, and suggest a novel mechanism by which heparanase increases the generation of activated factor X in the presence of tissue factor and activated factor VII.


Asunto(s)
Coagulación Sanguínea , Factor VIIa/metabolismo , Factor Xa/metabolismo , Glucuronidasa/metabolismo , Adolescente , Adulto , Anciano , Anticoagulantes/farmacología , Factor VIIa/genética , Factor Xa/genética , Femenino , Glucuronidasa/antagonistas & inhibidores , Glucuronidasa/genética , Glicoproteínas/farmacología , Células HEK293 , Heparina/farmacología , Humanos , Leucemia Mieloide Aguda/enzimología , Leucemia Mieloide Aguda/genética , Masculino , Persona de Mediana Edad , Leucemia-Linfoma Linfoblástico de Células Precursoras/enzimología , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Inhibidores de Serina Proteinasa/farmacología , Tromboplastina/genética , Tromboplastina/metabolismo
3.
Am J Cardiol ; 101(10): 1384-8, 2008 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-18471446

RESUMEN

Increase of cardiac troponins occurs in a variety of clinical situations in the absence of an acute coronary syndrome (ACS). Few data exist regarding the incidence, clinical characteristics, and predictive value of various cardiac diagnostic tests and outcome of patients with a non-ACS-related troponin increase. We studied 883 consecutive hospitalized patients with increased cardiac troponin I levels. The discharge diagnosis was reclassified and troponin increase attributed to ACS or another process. Clinical data and results of cardiac diagnostic tests were collected. Patients were followed for a median of 30 months. Three hundred eleven patients were classified as having a non-ACS-related troponin increase (35.2%). An alternative explanation for troponin increase was found in 99% of these patients. Troponin level had poor accuracy in discriminating patients with and without ACS (area under the receiver operating characteristics curve 0.63). Coronary angiography was frequently unhelpful in excluding a non-ACS-related troponin increase because 77% of patients in the non-ACS group had significant flow-limiting coronary artery disease. Patients with non-ACS-related troponin increase had significantly higher in-hospital (hazard ratio 2.8, 95% confidence interval 2.0 to 3.8) and long-term (hazard ratio 2.0, 95% confidence interval 1.6 to 2.5) mortalities compared with patients with ACS. In conclusion, cardiac troponin level is frequently increased in hospitalized patients in the absence of an ACS and portends poor short- and long-term outcomes. Most of these patients have an alternative explanation for cardiac troponin increase. Cardiac diagnostic procedures are frequently unhelpful in excluding a non-ACS-related troponin increase.


Asunto(s)
Enfermedad Coronaria/sangre , Pacientes Internos , Troponina I/sangre , Enfermedad Aguda , Anciano , Biomarcadores/sangre , Angiografía Coronaria , Enfermedad Coronaria/diagnóstico , Enfermedad Coronaria/mortalidad , Electrocardiografía , Femenino , Estudios de Seguimiento , Mortalidad Hospitalaria/tendencias , Humanos , Israel/epidemiología , Masculino , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Curva ROC , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Tasa de Supervivencia/tendencias , Síndrome
4.
Toxicol Mech Methods ; 18(9): 745-50, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20020934

RESUMEN

ABSTRACT Venous PCO(2) and PO(2) in the presence of normal arterial PCO(2) and PO(2) in patients with alcoholic intoxication have not been previously evaluated. The objective of this study was to compare arterial and venous blood gases in patients with alcoholic intoxication and healthy controls. Sixteen patients with alcoholic intoxication and 20 controls underwent simultaneous blood sampling from a radial artery and an antecubital vein for acid-base analysis. Osmolality and ethanol blood concentration was estimated. Elevated venous pO(2) were found in 56% of patients with alcoholic poisoning compared with 15% of controls. A formula was found describing possible arterio-venous shunt accounting for elevated venous pO(2) and enabling calculation of the relevant venous carbon dioxide content and CO(2) product. The values of the venous pO(2) and arterio-venous shunt were more significant in the alcohol group than in controls (p = 0.002, p = 0.001, respectively). Percentage of patients with a-v shunts was significantly higher in the alcohol group (81%) than in controls (25%) (p = 0.002, OR 2.6, 95% CI 0.13-6.52). The relevant venous CO(2) and CO(2) product had the non-significant trend to be higher in the alcohol group. In conclusion, this study reports ethanol-induced venous pO(2) and pCO(2) elevation. This may be associated with the effects of tissue perfusion stealing and high oxygen consumption. On the other hand, possible beneficial consequences may occur: acceleration of alcohol elimination and reduction of alcohol-induced tissue damage.

5.
Clin Nutr ; 23(3): 423-33, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15158307

RESUMEN

Dietary supplementation with polyphenolic antioxidants to animals was shown to be associated with inhibition of LDL oxidation and macrophage foam cell formation, and attenuation of atherosclerosis development. We investigated the effects of pomegranate juice (PJ, which contains potent tannins and anthocyanins) consumption by atherosclerotic patients with carotid artery stenosis (CAS) on the progression of carotid lesions and changes in oxidative stress and blood pressure. Ten patients were supplemented with PJ for 1 year and five of them continued for up to 3 years. Blood samples were collected before treatment and during PJ consumption. In the control group that did not consume PJ, common carotid intima-media thickness (IMT) increased by 9% during 1 year, whereas, PJ consumption resulted in a significant IMT reduction, by up to 30%, after 1 year. The patients' serum paraoxonase 1 (PON 1) activity was increased by 83%, whereas serum LDL basal oxidative state and LDL susceptibility to copper ion-induced oxidation were both significantly reduced, by 90% and 59%, respectively, after 12 months of PJ consumption, compared to values obtained before PJ consumption. Furthermore, serum levels of antibodies against oxidized LDL were decreased by 19%, and in parallel serum total antioxidant status (TAS) was increased by 130% after 1 year of PJ consumption. Systolic blood pressure was reduced after 1 year of PJ consumption by 12% [corrected] and was not further reduced along 3 years of PJ consumption. For all studied parameters, the maximal effects were observed after 1 year of PJ consumption. Further consumption of PJ, for up to 3 years, had no additional beneficial effects on IMT and serum PON1 activity, whereas serum lipid peroxidation was further reduced by up to 16% after 3 years of PJ consumption. The results of the present study thus suggest that PJ consumption by patients with CAS decreases carotid IMT and systolic blood pressure and these effects could be related to the potent antioxidant characteristics of PJ polyphenols.


Asunto(s)
Antioxidantes/farmacología , Bebidas , Presión Sanguínea/efectos de los fármacos , Estenosis Carotídea/tratamiento farmacológico , Lythraceae , Estrés Oxidativo/efectos de los fármacos , Fitoterapia , Anciano , Antioxidantes/uso terapéutico , Arildialquilfosfatasa/sangre , Estenosis Carotídea/etiología , Estenosis Carotídea/fisiopatología , LDL-Colesterol/sangre , LDL-Colesterol/inmunología , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Enfermedad de la Arteria Coronaria/fisiopatología , Suplementos Dietéticos , Progresión de la Enfermedad , Femenino , Humanos , Hipertensión/metabolismo , Hipertensión/prevención & control , Metabolismo de los Lípidos , Peroxidación de Lípido/efectos de los fármacos , Lythraceae/química , Masculino , Oxidación-Reducción , Túnica Íntima/efectos de los fármacos , Túnica Íntima/patología
6.
Nutrition ; 18(3): 268-73, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11882402

RESUMEN

OBJECTIVE: We previously demonstrated the beneficial effects of dietary flavonoids derived from the ethanolic extract of licorice root against atherosclerotic lesion development in association with inhibition of low-density lipoprotein (LDL) oxidation in atherosclerotic mice. Administration of licorice extract to normolipidemic subjects also inhibited LDL oxidation. In the present study, we extended our investigation to analyze the antiatherogenic effects of licorice-root extract consumption in moderately hypercholesterolemic patients. METHODS: Supplementation of licorice root extract (0.1 g/d) to patients for 1 mo was followed by an additional 1 mo of placebo consumption. RESULTS: Licorice consumption 1) reduced patients' plasma susceptibility to oxidation (by 19%); 2) increased resistance of plasma LDL against three major atherogenic modifications: oxidation (by 55%), aggregation (by 28%), and retention, estimated as chondroitin sulfate binding ability (by 25%); 3) reduced plasma cholesterol levels (by 5%), which was due to a 9% reduction in plasma LDL cholesterol levels; and 4) reduced (by 14%) plasma triacylglycerol levels. After the 1 mo of placebo consumption, these parameters reversed toward baseline levels. Licorice extract supplementation also reduced systolic blood pressure by 10%, which was sustained during the placebo consumption. CONCLUSIONS: Dietary consumption of licorice-root extract by hypercholesterolemic patients may act as a moderate hypocholesterolemic nutrient and a potent antioxidant agent and, hence against cardiovascular disease.


Asunto(s)
Anticolesterolemiantes/uso terapéutico , Glycyrrhiza , Hipercolesterolemia/tratamiento farmacológico , Fitoterapia , Extractos Vegetales/uso terapéutico , Anticolesterolemiantes/farmacología , Presión Sanguínea/efectos de los fármacos , Colesterol/sangre , Suplementos Dietéticos , Femenino , Glycyrrhiza/química , Humanos , Peroxidación de Lípido/efectos de los fármacos , Lipoproteínas LDL/sangre , Lipoproteínas LDL/metabolismo , Masculino , Persona de Mediana Edad , Oxidación-Reducción , Extractos Vegetales/farmacología , Triglicéridos/sangre
7.
Atherosclerosis ; 232(1): 204-10, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24401239

RESUMEN

OBJECTIVE: To analyze pomegranate extract (POMx) effects on serum and on human HMDM atherogenicity in simvastatin - treated hypercholesterolemic patients. METHODS AND RESULTS: Patients were randomly assigned to receive either simvastatin (20 mg/day) + vegan placebo pill (n = 11), or simvastatin (20 mg/day) + POMx pill (1g/day, n = 12). Fasting blood samples were collected at baseline and after 1 and 2 months of therapy. HMDM were collected from 3 patients in each group at baseline and after 2 months of therapy, as well as from 3 healthy subjects. After 2 months of therapy, serum LDL-cholesterol levels significantly decreased, by 23%, in the simvastatin + placebo group, and by 26% in the simvastatin + POMx group. Simvastatin + POMx therapy increased serum thiols concentration by 6%. Patients' HMDM reactive oxygen species (ROS) levels were significantly increased, by 69%, vs. healthy subjects HMDM. After 2 months of therapy, HMDM ROS levels decreased by 18% in the simvastatin + placebo group, whereas in the simvastatin + POMx group it decreased by up to 30%. A novel finding was the triglycerides levels in the patients' HMDM at baseline which were significantly higher, by 71%, vs. healthy subjects HMDM. The simvastatin + POMx, but not the simvastatin + placebo therapy, significantly reduced macrophage triglycerides content by 48%, vs. baseline levels. In addition, whereas the simvastatin + placebo therapy significantly decreased the patients' HMDM cholesterol biosynthesis rate by 33%, the simvastatin + POMx therapy further decreased it, by 44%. CONCLUSION: The addition of POMx to simvastatin therapy in hypercholesterolemic patients improved oxidative stress and lipid status in the patient's serum and in their HMDM. These anti-atherogenic effects could reduce the risk for atherosclerosis development.


Asunto(s)
Aterosclerosis/tratamiento farmacológico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Hipercolesterolemia/tratamiento farmacológico , Macrófagos/efectos de los fármacos , Monocitos/efectos de los fármacos , Extractos Vegetales/administración & dosificación , Simvastatina/administración & dosificación , Adulto , Animales , Aterosclerosis/sangre , Aterosclerosis/prevención & control , Línea Celular , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Método Doble Ciego , Sinergismo Farmacológico , Humanos , Hipercolesterolemia/sangre , Leucocitos Mononucleares/citología , Lípidos/sangre , Lythraceae/química , Macrófagos/metabolismo , Masculino , Ratones , Persona de Mediana Edad , Estrés Oxidativo , Oxígeno/química , Proyectos Piloto , Estudios Prospectivos , Especies Reactivas de Oxígeno , Triglicéridos/sangre
8.
Food Funct ; 1(1): 99-109, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21776460

RESUMEN

The present study analyzed the antioxidative effects of various beverages, in vitro, and also the effect of short term consumption of beverages richest in polyphenols by healthy subjects on serum anti-atherogenic properties. Healthy subjects consumed 250 mL of the selected beverages for 2 h, or daily, for up to 1 week.We hypothesized that differences in the anti-atherogenic properties of the studied beverages could be related, not only to the quantity of polyphenols, but also to their quality. Furthermore, we hypothesized that consumption of these juices by healthy subjects for just a short-term, will increase their serum anti-atherogenic properties, as was demonstrated previously in long-term consumption studies.Of 35 beverages studied, both 100% Wonderful-variety pomegranate and 100% black currant juices were the most potent antioxidants in vitro, as they inhibited copper ion-induced LDL oxidation by up to 94% and AAPH-induced serum lipid peroxidation by up to 38%. Furthermore, they increased in vitro serum paraoxonase 1 (PON1) lactonase activity by up to 51%. Consumption of five selected polyphenol rich beverages by healthy subjects increased serum sulfhydryl group (SH) levels and serum PON1 activities after 2 h, and more so after 1 week of drinking these beverages. These effects were most pronounced after the consumption of 100% Wonderful-variety pomegranate and 100% black currant juices. In conclusion, polyphenolic-rich juices with impressive in vitro antioxidant properties, also demonstrate antioxidant effects in vivo when analyzed for short term consumption. In this respect, 100% Wonderful-variety pomegranate and 100% black currant juices were most the potent.


Asunto(s)
Antioxidantes/análisis , Bebidas , Colesterol/metabolismo , Frutas , Macrófagos/metabolismo , Polifenoles/administración & dosificación , Adulto , Animales , Arildialquilfosfatasa/sangre , Bebidas/análisis , Línea Celular , Medios de Cultivo , Frutas/química , Humanos , Lythraceae/química , Macrófagos/efectos de los fármacos , Masculino , Ratones , Estrés Oxidativo/efectos de los fármacos , Polifenoles/análisis , Polifenoles/sangre , Ribes/química , Suero
9.
J Agric Food Chem ; 56(21): 9884-91, 2008 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-18844360

RESUMEN

Antioxidant activity and composition of Israeli-grown marula ( Sclerocarrya birrea subsp. caffra) fruit juice and health-promoting aspects of juice consumption on serum lipids and lipoproteins pattern in healthy volunteers were studied. Marula juice was found to contain high vitamin C and potassium levels and low sugar concentration (267 mg dL (-1), 328 mg dL (-1), and 7.3 g dL (-1), respectively). The juice contains a significant level of phenolics (56 mg of pyrogallol equiv dL (-1)) and was found to be a potent antioxidant (382 mg of vitamin C equiv dL (-1)). The antioxidant activity was resistant to pasteurization regimens and long-term freezing and slowly decreased during refrigeration, losing up to 14% of its capacity after 4 weeks. Three-week administration of the juice as a food supplement to healthy subjects significantly reduced their serum total cholesterol (by 8%), LDL-cholesterol concentration (by 17%), and triglyceride level (by 7%), increased their serum HDL-cholesterol level (by 10%), and attenuated serum oxidative stress. Upon a 4 week "washout" period, most of these parameters returned toward baseline values. Separation of the juice soluble phenolics by HPLC produced potent antioxidant fractions, tentatively containing hydrolyzable tannins, catechins, and hydroxycinnamic acid derivatives, which could be responsible for the observed protection against atherosclerosis risk factors following marula fruit juice consumption.


Asunto(s)
Antioxidantes/farmacología , Aterosclerosis/prevención & control , Bebidas/análisis , Flavonoides/farmacología , Frutas/química , Fenoles/farmacología , Antioxidantes/análisis , Colesterol/sangre , Suplementos Dietéticos/análisis , Flavonoides/análisis , Humanos , Fenoles/análisis , Polifenoles , Triglicéridos/sangre
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