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1.
Mol Nutr Food Res ; 54(11): 1636-45, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20540144

RESUMEN

White tea (WT) is rich in flavan-3-ols as green tea (GT) and might provide health protective effects due to the strong antioxidant properties of flavan-3-ols. Since intervention studies with WT are lacking, we evaluated the effects of WT consumption on antioxidant status, antioxidant capacity and biomarkers of oxidative stress compared to water and GT. After an overnight fast, 70 healthy non-smokers were randomized to consume 600 mL of WT, GT or water (control). Plasma (epi-)catechin and epi(gallo)catechingallate, antioxidant capacity (Folin assay, trolox equivalent antioxidant capacity test), 8-iso-prostaglandin F(2α), ascorbic acid and uric acid were determined before and several times within 8 h after consumption. DNA strand breaks were measured in vivo and ex vivo (H(2)O(2) stimulation) in leukocytes. Plasma flavan-3-ols significantly increased after WT and GT ingestion. Trolox equivalent antioxidant capacity was lower after 5 h in controls versus WT (p = 0.031) and GT (p = 0.005). Folin-Ciocalteu reducing capacity, ascorbic and uric acid as well as markers of oxidative stress (8-iso-prostaglandin-F(2α), DNA strand breaks) were not affected by the beverages. A short-term increase of catechins does not change plasma antioxidant capacity in healthy subjects. Conclusions with respect to health protective effects of WT and GT on the basis of these biomarkers can, thus, not be drawn.


Asunto(s)
Antioxidantes/farmacología , Biomarcadores , Flavonoides/sangre , Estrés Oxidativo , Té/metabolismo , Adulto , Ácido Ascórbico/sangre , Catequina/sangre , Femenino , Flavonoides/farmacología , Humanos , Peróxido de Hidrógeno/metabolismo , Leucocitos/metabolismo , Masculino , Extractos Vegetales/sangre , Plasma/metabolismo , Fumar , Adulto Joven
2.
Phytomedicine ; 16(1): 2-16, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19118991

RESUMEN

The maintenance of the redox-homeostasis is an essential task of antioxidants. Reactive oxygen species (ROS) formed during oxidative stress can potentially damage the normal cellular functions and support pathological processes like atherosclerosis in vessels or malignant growth in other tissues, but also the aging process. However, recent findings link ROS also to cell survival and/or proliferation, which revolutionises the age-old dogmatic view of ROS being exclusively involved in cell damage and death. Low concentrations of hydrogenperoxide e.g. are involved in cell signaling and can activate mitogen-activated kinases (MAPK) to initiate cell growth. Nutritional antioxidants like vitamin C or E can promote endothelial cell growth, but can also inhibit growth of muscle cells, and influence MAPK. Thus, keeping the redox-homeostasis in a steady state especially in the context of tissue regeneration appears to be more important than previously known and seems to be a controlled synergistic action of antioxidants and ROS. The present review summarizes the properties and functions of ROS and nutritional antioxidants like the vitamins C and E, and polyphenols in redox-homeostasis. Their relevance in the treatment of various diseases is discussed in the context of a multitarget therapy with nutraceuticals and phytotherapeutic drugs.


Asunto(s)
Antioxidantes/farmacología , Suplementos Dietéticos , Homeostasis/efectos de los fármacos , Fitoterapia , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacos , Antioxidantes/uso terapéutico , Supervivencia Celular/efectos de los fármacos , Flavonoides/farmacología , Flavonoides/uso terapéutico , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Oxidación-Reducción/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Fenoles/farmacología , Fenoles/uso terapéutico , Polifenoles
3.
Obes Surg ; 18(10): 1354-6, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18528737

RESUMEN

Multiple benign symmetric lipomatosis (MSL) is characterized by a rapid progression of multiple, symmetric nonencapsulated fat masses in the face, neck, and extremities. The lipomas are thought to be the result of defective brown adipose tissue (BAT). In up to 90% MSL is associated with chronic alcohol abuse. Prognosis depends on the concomitant presence of a neuropathy with a mortality of 25.8%. Therapeutic options are limited to alcohol abstinence and surgical interventions. We report here about a 53-year-old MSL patient who increased his body weight by 37 kg over 10 years. Multiple lipectomies were performed, but disease progressed. We treated him with fenofibrates (200 mg/day). Disease progression discontinued and circumferences of abdominal adipose tissue reduced. Fibrates, peroxisome proliferator-activated receptor alpha (PPAR alpha) agonists, are pleiotropic hypolipidemic drugs, and might have worked by suppression of protein expressions involved in the architecture of BAT keeping it in a quiescent state.


Asunto(s)
Fenofibrato/uso terapéutico , Hipolipemiantes/uso terapéutico , Lipomatosis Simétrica Múltiple/diagnóstico , Lipomatosis Simétrica Múltiple/tratamiento farmacológico , Obesidad/diagnóstico , Diagnóstico Diferencial , Humanos , Lipomatosis Simétrica Múltiple/cirugía , Masculino , Persona de Mediana Edad
4.
J Toxicol Environ Health A ; 71(13-14): 887-97, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18569591

RESUMEN

Tobacco smoking, alcohol drinking, and occupational exposures to polycyclic aromatic hydrocarbons are the major proven risk factors for human head and neck squamous-cell cancer (HNSCC). Major research focus on gene-environment interactions concerning HNSCC has been on genes encoding enzymes of metabolism for tobacco smoke constituents and repair enzymes. To investigate the role of genetically determined individual predispositions in enzymes of xenobiotic metabolism and in repair enzymes under the exogenous risk factor tobacco smoke in the carcinogenesis of HNSCC, we conducted a case-control study on 312 cases and 300 noncancer controls. We focused on the impact of 22 sequence variations in CYP1A1, CYP1B1, CYP2E1, ERCC2/XPD, GSTM1, GSTP1, GSTT1, NAT2, NQO1, and XRCC1. To assess relevant main and interactive effects of polymorphic genes on the susceptibility to HNSCC we used statistical models such as logic regression and a Bayesian version of logic regression. In subgroup analysis of nonsmokers, main effects in ERCC2 (Lys751Gln) C/C genotype and combined ERCC2 (Arg156Arg) C/A and A/A genotypes were predominant. When stratifying for smokers, the data revealed main effects on combined CYP1B1 (Leu432Val) C/G and G/G genotypes, followed by CYP1B1 (Leu432Val) G/G genotype and CYP2E1 (-70G>T) G/T genotype. When fitting logistic regression models including relevant main effects and interactions in smokers, we found relevant associations of CYP1B1 (Leu432Val) C/G genotype and CYP2E1 (-70G>T) G/T genotype (OR, 10.84; 95% CI, 1.64-71.53) as well as CYP1B1 (Leu432Val) G/G genotype and GSTM1 null/null genotype (OR, 11.79; 95% CI, 2.18-63.77) with HNSCC. The findings underline the relevance of genotypes of polymorphic CYP1B1 combined with exposures to tobacco smoke.


Asunto(s)
Carcinoma de Células Escamosas/genética , Neoplasias de Cabeza y Cuello/genética , Polimorfismo Genético/genética , Xenobióticos/metabolismo , Distribución por Edad , Secuencia de Bases , Teorema de Bayes , Estudios de Casos y Controles , Reparación del ADN/genética , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Caracteres Sexuales , Fumar , Toxicogenética
5.
J Toxicol Environ Health A ; 71(11-12): 803-15, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18569579

RESUMEN

Tobacco smoke and occupational exposures to chemicals such as polycyclic aromatic hydrocarbons (PAHs) are, aside from alcohol, the major risk factors for development of head and neck squamous-cell cancer (HNSCC). In this study, new statistical methods were applied. We employ new statistical methods to detect genetic interactions perhaps of higher order, that might play a role in developing HNSCC. The underlying study comprises 312 HNSCC cases and 300 controls. Single-nucleotide polymorphisms (SNPs) of PAH metabolizing and repair enzymes, somatic p53 mutations, and tobacco smoke were examined. Key statistical tools for our analysis are methods of unsupervised and supervised learning. In unsupervised learning, one performs cluster analyses based on well-known and new distance measures to find differences in the SNP patterns of cases and controls, and to understand the role of p53. Our main goal in supervised learning was to identify SNPs and SNP interactions that are likely to alter the susceptibility to HNSCC. Logic regression, a classification method well suited for SNPs, was employed as well as a Bayesian generalization that allows for incorporating additional expert knowledge. These methods detected several important interactions, such as an association between CYP1B1, tobacco smokes and p53 mutations and some interactions between CYP1B1 and glutathione S-transferases in smokers, which included a three-way interaction between CYP1B1, CYP2E1-70G>T, and GSTP1 (exon 5).


Asunto(s)
Carcinoma de Células Escamosas/genética , Predisposición Genética a la Enfermedad , Neoplasias de Cabeza y Cuello/genética , Modelos Estadísticos , Hidrocarburo de Aril Hidroxilasas/genética , Teorema de Bayes , Carcinoma de Células Escamosas/sangre , Estudios de Casos y Controles , Análisis por Conglomerados , Citocromo P-450 CYP1B1 , ADN de Neoplasias/sangre , Interpretación Estadística de Datos , Femenino , Genes p53/genética , Glutatión Transferasa/genética , Neoplasias de Cabeza y Cuello/sangre , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Fumar , Tabaquismo/genética
6.
Rheumatol Int ; 28(10): 1017-22, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18368410

RESUMEN

Serotonin antagonists show impressive analgesic efficacy in rheumatoid arthritis, osteoarthritis (OA) or fibromyalgia; however, this effect is not well understood. We examined the mechanism of serotonin-induced inflammation and its antagonists in OA. Serotonin receptor subtypes and COX-2 were analysed by RT-PCR from synovial tissue. Serum-free cultures were stimulated with 10 muM serotonin and/or the antagonists ketanserin (5-HT(2A)), tropisetron (5-HT(3)) and parecoxib (COX-2). Prostaglandin E(2) (PGE(2)), tumour necrosis factor alpha (TNF-alpha), interleukin 1beta (IL-1beta) and leukotriene B4 (LTB4) were measured by an immunoassay in the supernatants. RT-PCR results showed mRNA for 5-HT(2A) and 5-HT(3) receptors, and COX-2. PGE(2) in the supernatants increased by 261.2% +/- 56.7 (mean +/- SEM; P = 0.007) in response to serotonin. TNF-alpha, IL-1beta and LTB4 levels did not change. Ketanserin, tropisetron and parecoxib suppressed PGE(2). The serotonin-induced PGE(2) overexpression appeared thus to be mediated by 5-HT(2A) and 5-HT(3) receptors. This activation might involve COX-2. The findings may explain the potent benefit of 5-HT(3) antagonists.


Asunto(s)
Dinoprostona/metabolismo , Macrófagos/fisiología , Osteoartritis/patología , Receptor de Serotonina 5-HT2A/genética , Receptores de Serotonina 5-HT3/genética , Serotonina/farmacología , Membrana Sinovial/citología , Anciano , Células Cultivadas , Medio de Cultivo Libre de Suero , Ciclooxigenasa 2/genética , Ciclooxigenasa 2/metabolismo , Inhibidores de la Ciclooxigenasa/farmacología , Interacciones Farmacológicas , Humanos , Indoles/farmacología , Interleucina-1beta/metabolismo , Isoxazoles/farmacología , Ketanserina/farmacología , Leucotrieno B4/metabolismo , Macrófagos/citología , Macrófagos/efectos de los fármacos , Persona de Mediana Edad , Osteoartritis/metabolismo , Osteoartritis/fisiopatología , ARN Mensajero/metabolismo , Receptor de Serotonina 5-HT2A/metabolismo , Receptores de Serotonina 5-HT3/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Serotoninérgicos/farmacología , Antagonistas de la Serotonina/farmacología , Tropisetrón , Factor de Necrosis Tumoral alfa/metabolismo
7.
Pulm Pharmacol Ther ; 21(3): 533-9, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18295521

RESUMEN

Endothelin (ET) stimulates potent ETA/ETB receptors important in the pathogenesis of pulmonary arterial hypertension (PAH) and fibrosis. Though therapy with ET-receptor antagonists is well established uncertainty exists whether selective ETA or dual ETA/ETB-receptor antagonism is superior in PAH. The objective of this study was to further elucidate the pro-inflammatory effects of ET-1 on ETB receptors in cultured human monocytes (10(5)/20 h) compared with non-specific stimulation with LPS in vitro and to define the antagonizing effects of bosentan, a dual ETA/ETB-receptor antagonist, on inflammatory mediator production. We further hypothesized that ETB-receptor antagonism reduces the requirement of PGE2 to control inflammatory mediator production. Activation of the monocyte ETB subtype by ET (1 ng/ml) concentration-dependently stimulated TNF-alpha (744%) >PGE2 (570%) > IL-1 beta (112%) and had no effect on 5-lipoxygenase metabolism. Compared with ET a different profile of IL-1 beta >TNF-alpha >PGE2 was induced by LPS. ETB-receptor antagonism attenuated ET- and LPS-responses in monocytes, in particular of TNF-alpha and PGE2 to a similar extend (40%) that were only demonstrable following LPS at therapeutic plasma concentrations of bosentan and had no effect on IL-1 beta. Inhibition of ETB receptors in LPS-stimulated monocytes by bosentan was responded with suppression of PGE2 and increased production of leukotrienes indicating strong effects in the cyclooxygenase pathway that is known to control cellular ET transcription. These data suggest an important signaling pathway between ET-induced cytokine production following ETB-receptor activation with no further control of ET transcription by PGE2 required following ETB receptor antagonism. Therefore, in states of inflammation increased ETB-receptor expression and activation mediated by elevated ET concentrations may be an underestimated mechanism, which warrants the application of combined ETA/ETB-receptor antagonists.


Asunto(s)
Antiinflamatorios/farmacología , Antagonistas de los Receptores de la Endotelina B , Inflamación/inducido químicamente , Inflamación/patología , Monocitos/efectos de los fármacos , Monocitos/patología , Receptor de Endotelina B/agonistas , Antihipertensivos/farmacología , Ácido Araquidónico/metabolismo , Bosentán , Línea Celular , Separación Celular , Dinoprostona/biosíntesis , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Humanos , Técnicas In Vitro , Interleucina-1beta/metabolismo , Inhibidores de la Lipooxigenasa/farmacología , Monocitos/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sulfonamidas/farmacología , Factor de Necrosis Tumoral alfa/metabolismo
8.
Obes Surg ; 18(2): 240-2, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18175197

RESUMEN

Multiple benign symmetric lipomatosis (MSL) is characterized by a rapid progression of multiple, symmetric nonencapsulated fat masses in face, neck, and extremities. The lipomas are thought to be the result of defective brown adipose tissue (BAT). In up to 90%, MSL is associated with chronic alcohol abuse. Prognosis depends on the concomitant presence of a neuropathy with a mortality of 25.8%. Therapeutic options are limited to alcohol abstinence and surgical interventions. We report here about a 53-year-old MSL patient who increased his body weight by 37 kg over 10 years. Multiple lipectomies were performed but disease progressed. We treated him with fenofibrates (200 mg/day). Disease progression discontinued, and circumferences of abdominal adipose tissue reduced. Fibrates, peroxisome proliferator-activated receptor alpha agonists, are pleiotropic hypolipidemic drugs and might have worked by suppression of protein expressions involved in the architecture of BAT keeping it in a quiescent state.


Asunto(s)
Ácido Clofíbrico/uso terapéutico , Lipomatosis Simétrica Múltiple/diagnóstico , Obesidad/diagnóstico , Diagnóstico Diferencial , Humanos , Lipomatosis Simétrica Múltiple/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Obesidad/tratamiento farmacológico , Inducción de Remisión
9.
Atherosclerosis ; 196(1): 92-97, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17350025

RESUMEN

Epidermal growth factor (EGF) has been shown to be a potent mitogen for vascular smooth muscle cells (VSMC) both in vitro and in vivo, thus contributing to the development of atherosclerosis and hypertension. Stimulation of Rho-family GTPases Rac/Cdc42 exerts pleiotropic cellular effects and have been demonstrated to contribute to EGF-induced proliferation in other cell systems. However, the effect of EGF on Rac/Cdc42 activation is unknown for VSMC. In the present report, we evaluated stimulation of Rac/Cdc42 by EGF in VSMC performing PAK-PBD binding assay. EGF treatment of VSMC induced time and concentration dependent binding of GTP-bound Rac1 to PAK-PBD peaking at 1 min and showing sustained activation up to 15 min. However, stimulation of Cdc42 could not be demonstrated. To further evaluate downstream effectors of Rac1 stimulation of p21-activated kinase (PAK) and c-Jun N-terminal kinase (JNK) by EGF was determined. In VSMC, EGF sequentially stimulated PAK, peaking at 5 min, and JNK, peaking at 15 min. Pretreatment of VSMC by EGF receptor specific tyrosine kinase inhibitor AG1478 and non-specific tyrosine kinase inhibitor genistein inhibited EGF-induced activation of Rac1, PAK and JNK, whereas tyrosine kinase inhibitors specific for Src (PP1) and specific for platelet-derived growth factor (AG1296) had no effect. Specific inhibition or Rac1 by NSC23766 attenuated EGF-induced [(3)H] thymidine incorporation in VSMC. Our data provide evidence for EGF-induced Rac1 activation and implicate PAK and JNK as downstream targets of Rac1 in EGF signal transduction in VSMC.


Asunto(s)
Factor de Crecimiento Epidérmico/fisiología , Músculo Liso Vascular/metabolismo , Miocitos del Músculo Liso/fisiología , Quinasas p21 Activadas/metabolismo , Proteína de Unión al GTP rac1/metabolismo , Animales , Células Cultivadas , MAP Quinasa Quinasa 4/metabolismo , Masculino , Músculo Liso Vascular/citología , Ratas , Ratas Wistar , Transducción de Señal
10.
Rev. fitoter ; 7(2): 115-129, jul.-dic. 2007. tab, ilus
Artículo en Español | IBECS | ID: ibc-132766

RESUMEN

La demostración de la eficacia de los preparados fitoterápicos y la determinación de sus mecanismos de acción son retos permanentes para la fitoterapia basada en la evidencia. La genómica, proteómica y metabolómica son tecnologías de alto rendimiento, que permiten detectar simultáneamente un gran número de proteínas/genes, así como relacionar mezclas complejas con efectos complejos en forma de perfiles de expresión génica/proteica. La descripción de perfiles de expresión específicos para un determinado preparado fitoterápico puede ser útil para su estandarización química y farmacológica, así como para la evaluación de su toxicidad. A largo plazo, pueden economizar los estudios de eficacia y de mecanismos de acción, y facilitar la investigación de extractos vegetales carentes de principio(s) activo(s) predominantes. Se ha descubierto que los perfiles de expresión génica inducidos por fármacos individuales o sus combinaciones pueden ser completamente diferentes. La aplicación de las tecnologías “ómicas” puede suponer un cambio de paradigma en cuanto a la aplicación de mezclas complejas en medicina y abrir nuevos campos como la fitogenómica, fitoproteómica y fitometabolómica (AU)


The proof of efficacy of phytopreparations and the determination of their mode of action are permanent challenges for an evidence-based phytotherapy. Genomics, proteomics and metabolomics are high-throughput technologies that allow the simultaneous detection of a high number of proteins/genes and have the potential to relate complex mixtures to complex effects in the form of gene/ protein expression profiles. The development of phytopreparation-specific expression profiles will be useful for its chemical and pharmacological standardization and its toxicological assessment. Over a long-term perspective they may economize the studies on efficacy and mode of action of phytomedicines and allow to investigate herbal extracts without prominent active principle(s). The application of genomics revealed already that the gene expression profiles induced by single drugs and their combinations can be entirely different. The application of the “-omic-” technologies may lead to a change of paradigms towards the application of complex mixtures in medicine and open the new fields of phytogenomics, -proteomics and -metabolomics (AU)


Asunto(s)
Urtica dioica , Urtica dioica/inmunología , Fitoterapia , Mecanismo de Acción del Medicamento Homeopático , Genómica/métodos , Genómica/tendencias , Proteómica/métodos , Metabolómica/métodos , Metabolómica/tendencias , Resultado del Tratamiento , Evaluación de Eficacia-Efectividad de Intervenciones , Sinergismo Farmacológico , Biología de Sistemas/métodos , Biología de Sistemas/tendencias
11.
Eur J Nutr ; 46(8): 431-8, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17965904

RESUMEN

BACKGROUND: Endothelial dysfunction, common to diabetes and cardiovascular diseases, is an early step in the development of atherosclerosis and diabetic angiopathies. Deficiencies of taurine have been related to diabetes and cardiovascular diseases. AIMS OF THE STUDY: We investigated whether taurine provides protective action against endothelial dysfunction induced by hyperglycemia and/or oxidized low density lipoproteins (oxLDL). METHODS: Quiescent human umbilical cord venous endothelial cells were exposed for 20 h to high glucose (35 mM) and/or oxLDL (60 microg/ml) alone and in presence of taurine (0.5-2.5 mg/ml). Apoptosis, caspase-3 activity, soluble(s) and cell surface expressions of vascular cellular (VCAM-1) and intercellular (ICAM-1) adhesion molecules were determined. Results are given as a percentage of the low glucose medium control. Apoptosis, VCAM-1 and ICAM-1 expressions were related to cell number. RESULTS: Hyperglycemia increased apoptosis to 162.5 +/- 19.2%, caspase-3 activity to 153.2 +/- 10.3%, cell-surface expression of VCAM-1 to 125.1 +/- 5.8%, the expression of ICAM-1 to 123.7 +/- 2.8% and sICAM-1 to 146.5 +/- 7.9%. Taurine (0.5-2.5 mg/ml) restored apoptosis, caspase-3 activity and expressions of VCAM-1 and ICAM-1. OxLDL (60 microg/ml) increased apoptosis to 114.8 +/- 3.1%; taurine (2.5 mg/ml) reduced this apoptosis to 40.5 +/- 4.1%. The combination of hyperglycemia and oxLDL increased apoptosis to 211.7 +/- 11.6%. This increase was normalized by taurine (2.5 mg/ml) to 97.9 +/- 12.8%. CONCLUSION: Taurine protects HUVECs from endothelial dysfunction induced by hyperglycemia through down-regulation of apoptosis and adhesion molecules. Counteracting the combination of oxLDL and hyperglycemia requires pharmacological concentrations of taurine.


Asunto(s)
Células Endoteliales/efectos de los fármacos , Glucosa/farmacología , Lipoproteínas LDL/farmacología , Taurina/deficiencia , Taurina/farmacología , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Células Cultivadas , Relación Dosis-Respuesta a Droga , Humanos , Molécula 1 de Adhesión Intercelular/metabolismo , Lipoproteínas LDL/química , Oxidación-Reducción , Venas Umbilicales/citología , Molécula 1 de Adhesión Celular Vascular/metabolismo
12.
Eur J Nutr ; 46(2): 87-94, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17225921

RESUMEN

BACKGROUND: Epidemiological, secondary prevention and small interventional trials suggest a preventive role of vitamin C for cardiovascular diseases (CAD), especially through improving endothelial dysfunction. Large primary prevention trials failed to confirm this. Mechanistic studies may contribute to resolve this discrepancy. AIM OF THE STUDY: We examined whether vitamin C activates mitogen-activated protein kinases (MAPK) in human umbilical cord venous endothelial cells (HUVECs) and whether reactive oxygen species (ROS) play a role in this process. METHODS: Subconfluent quiescent HUVECs were incubated with vitamin C alone or in combination with catalase (CAT) and/or hydrogenperoxide (H2O2). Intracellular MAPK were determined by Western blot, proliferation by cell count and DNA-synthesis by [3H]-thymidine-uptake. RESULTS: HUVECs were incubated with vitamin C (60 microM) for 5-60 min or for 20 min (30-90 microM). A dose-dependent phosphorylation of extracellular signal-regulated-kinases (ERKs)-1 and -2 with a maximum of phosphorylation at 15-20 min was observed and inhibitable by MEK1/2-inhibitor U0126 (5-10 microM). Vitamin C (60 microM) stimulated phosphorylation of ERK5, but not of p38 and c-Jun, demonstrating a different MAPK-activation pattern compared to H2O2. Vitamin C (60 microM) induced proliferation and a dose-dependent [3H]-thymidine-uptake (30-120 microM) within 20 h. CAT (0.3 U/ml) did neither suppress the vitamin C induced [3H]-thymidine-uptake nor ERK1/2-phosphorylation. CAT (0.3 U/ml), but not vitamin C (60 microM) abrogated the inhibitory effects of H2O2 (100 microM) on [3H]-thymidine-uptake. CONCLUSION: Physiological vitamin C-concentrations promote proliferation of subconfluent ECs by activating an ERK1/2 controlled pathway. Targeting MAPK by vitamin C may improve, besides antioxidant mechanisms, endothelial dysfunction by promoting a fast regeneration of the endothelium after tissue injury, particularly required during secondary prevention and early development.


Asunto(s)
Antioxidantes/farmacología , Ácido Ascórbico/farmacología , Proliferación Celular/efectos de los fármacos , Células Endoteliales/efectos de los fármacos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Western Blotting , Butadienos/farmacología , ADN/biosíntesis , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/farmacología , Humanos , Peróxido de Hidrógeno/metabolismo , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Nitrilos/farmacología , Fosforilación , Especies Reactivas de Oxígeno/metabolismo , Factores de Tiempo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
13.
Clin Drug Investig ; 26(8): 439-46, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17163276

RESUMEN

OBJECTIVES: This subanalysis of the OLMETEL (OLMEsartan TELemonitoring blood pressure) study in patients with essential hypertension assessed the relationship between the frequency of blood pressure self-measurement (BPSM) and the response to blood pressure (BP)-lowering therapy with olmesartan medoxomil, and the number of BP readings per week necessary to detect a mean systolic or diastolic BP reduction > or =5mm Hg. METHODS: A total of 53 patients with essential hypertension received treatment with olmesartan medoxomil 10, 20 or 40 mg daily for 12 weeks. BPSM was performed for the first 9 weeks using a TensioPhone TP2 device. Patients were instructed to measure BP at least twice daily (morning and evening). RESULTS: After the first 9 weeks of the 12-week treatment period, the extent of BP reduction correlated with the number of BPSMs. Systolic/diastolic BP reductions in patients with a 100% adherence to at least two BP measurements daily were -16.6/-8.0mm Hg compared with -0.2/-3.3mm Hg in patients with only a 75% adherence to at least one BP measurement daily. Obtaining five home BP readings per week resulted in a sensitivity of 94.8% and a specificity of 90.0% to detect a BP reduction of > or =5mm Hg. CONCLUSION: Patients adhering to the instructions for BPSM (at least two measurements daily) had a better response to antihypertensive treatment with olmesartan medoxomil. Whether BPSM per se resulted in an improved adherence to therapy or whether the number of recordings was an indicator of already existing adherence remains to be determined. Obtaining at least five home BP readings per week was identified as the threshold for correctly predicting response to olmesartan medoxomil treatment.


Asunto(s)
Monitoreo Ambulatorio de la Presión Arterial/instrumentación , Presión Sanguínea/efectos de los fármacos , Hipertensión/tratamiento farmacológico , Imidazoles/uso terapéutico , Tetrazoles/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Bloqueadores del Receptor Tipo 1 de Angiotensina II/administración & dosificación , Bloqueadores del Receptor Tipo 1 de Angiotensina II/uso terapéutico , Antihipertensivos/administración & dosificación , Antihipertensivos/uso terapéutico , Presión Sanguínea/fisiología , Monitoreo Ambulatorio de la Presión Arterial/métodos , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Humanos , Hipertensión/fisiopatología , Imidazoles/administración & dosificación , Masculino , Persona de Mediana Edad , Olmesartán Medoxomilo , Cooperación del Paciente , Reproducibilidad de los Resultados , Telemedicina/instrumentación , Telemedicina/métodos , Tetrazoles/administración & dosificación , Factores de Tiempo , Resultado del Tratamiento
14.
Pharmacology ; 78(3): 129-35, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17016062

RESUMEN

BACKGROUND/AIMS: Fexofenadine HCl (FEX) has previously been shown to have anti-inflammatory properties in relieving nasal congestion in allergic rhinitis. The objective of this study was to further elucidate the mechanism of action behind the anti-inflammatory properties of FEX in addition to its H(1)-receptor antagonism. METHODS: The effects of two antihistamines, FEX and loratadine (LOR), were investigated on cyclooxygenase (COX)-1 and -2 enzymes in vitro. FEX (10(-9)-10(-3) mol/l) and LOR (10(-9)-10(-4) mol/l) were incubated with arachidonic acid in a COX screening assay with either ovine COX-1 or COX-2 or human COX-2. COX-2 enzyme inhibitory activity for the antihistamines was compared with the known selective COX-2 inhibitor DuP-679. RESULTS: High concentrations of FEX (10(-3) mol/l) significantly inhibited arachidonic acid-mediated ovine COX-1 activity, but low concentrations had no effect. Low concentrations of FEX (10(-8) mol/l) inhibited ovine COX-2 activity, and this inhibition decreased with increasing concentrations. The inhibition of COX-2 activity by FEX was similar to that seen with the selective COX-2 inhibitor, DuP-679. Conversely, LOR inhibited COX-1 activity at low concentrations (10(-8) mol/l), but had little inhibitory effect on COX-1 at high concentrations. LOR (10(-5) mol/l) markedly stimulated COX-2 activity. CONCLUSION: FEX showed selective arachidonic acid-mediated COX-2 inhibitory enzyme activity, which differed markedly from the COX inhibitory enzyme activity of LOR. This selective COX-2 inhibitor activity by FEX may contribute to its anti-inflammatory properties in relieving nasal congestion in allergic rhinitis.


Asunto(s)
Ciclooxigenasa 1/química , Inhibidores de la Ciclooxigenasa 2/farmacología , Ciclooxigenasa 2/química , Antagonistas de los Receptores Histamínicos H1/farmacología , Terfenadina/análogos & derivados , Animales , Ácido Araquidónico/química , Relación Dosis-Respuesta a Droga , Humanos , Ovinos , Terfenadina/farmacología
15.
BMC Cardiovasc Disord ; 6: 36, 2006 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-16942618

RESUMEN

BACKGROUND: Incomplete drug regimen compliance (DRC) and white-coat hypertension are two of several possible causes of uncontrolled hypertension. Therefore the aim of the present study was to compare DRC in hypertensives treated with combination therapy whose blood pressures (BP) were controlled vers. uncontrolled after 4 weeks of self-monitored BP measurement. To observe the consequences in uncontrolled patients of switching one drug of the combination therapy to candesartan/HCTZ (16 mg/12.5 mg) with and without a compliance intervention program. METHODS: Self-and ambulatory-monitoring of BP were done with upper arm oscillometric devices. Patients' dosing histories were compiled electronically (MEMS, AARDEX). Patients with office blood pressure (OBP) >140/90 mmHg despite combination therapy were begun on MEMS monitoring and self BP measurement for 4 weeks of run-in. Of 62 such patients, 18 (29%) patients were normotensive according to self BP measurement and ambulatory BP measurement at 4 weeks (Group A); in the remaining 44 still uncontrolled patients, candesartan/HCTZ was substituted for one of the combination therapy drugs, with half these patients receiving passive compliance monitoring (B) and half a DRC intervention program (C). All groups were then followed for 8 weeks. RESULTS: DRC before week 4 was significantly higher in A than in the uncontrolled patients (B&C). DRC was stable during run-in A, but declined in B and C. DRC after week 4 was not different in the three groups and stayed constant over time. DRC during weekends was lower than during weekdays in all groups. In group A no significant change in blood pressure was observed with all three methods of BP measurements. In groups B and C significant reductions of systolic and diastolic BP were observed for ABPM and SBPM. After the change to candesartan/HCTZ in B&C ambulatory 24-h-BP (ABPM) was normalized in 39% of patients. CONCLUSION: Normalization of BP was associated with superior drug regimen compliance in previously uncontrolled patients treated with a combination drug regimen. Switching still-uncontrolled patients to candesartan/HCTZ significantly improved BP control and stabilized a declining DRC.


Asunto(s)
Antihipertensivos/uso terapéutico , Bencimidazoles/uso terapéutico , Monitoreo de Drogas/métodos , Hidroclorotiazida/uso terapéutico , Hipertensión/tratamiento farmacológico , Hipertensión/fisiopatología , Cooperación del Paciente , Tetrazoles/uso terapéutico , Anciano , Compuestos de Bifenilo , Presión Sanguínea , Determinación de la Presión Sanguínea/métodos , Quimioterapia Combinada , Electrónica Médica , Femenino , Humanos , Hipertensión/diagnóstico , Masculino , Persona de Mediana Edad , Visita a Consultorio Médico
16.
J Hypertens ; 24(10): 2085-90, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16957570

RESUMEN

OBJECTIVE: We have recently shown that mean pulse pressure is higher in patients with transient myocardial ischemia. Pulse pressure elevation might be an important consequence of increased arterial stiffness. The aim of this study was to prove if arterial stiffness is changed in patients with transient myocardial ischemia who bear a high cardiovascular risk. Additionally we investigated whether arterial stiffness or wave reflection is the best indicator for transient myocardial ischemia. Aortic pulse wave velocity (PWV) is a measure of arterial stiffness, and augmentation index (AIx) an indication of arterial wave reflection. Both are indicators for cardiovascular risk. METHODS: PWV (carotid-femoral) and AIx (SphygmoCor) were assessed in 74 hypertensive patients. Transient myocardial ischemia was detected using an ST-triggered 24-h ambulatory blood pressure monitoring device. RESULTS: ST-segment depressions were recorded in 30 of 74 patients. There were no significant differences with regard to age, mean arterial pressure, systolic blood pressure, diastolic blood pressure or heart rate. PWV was seen to be higher in patients with transient myocardial ischemia (10.6 versus 9.5 m/s, P = 0.036). There was no significant difference in AIx between the two groups. PWV (r = 0.36, P = 0.002) but not AIx correlated with pulse pressure. CONCLUSIONS: PWV is higher in hypertensive individuals (age > 60 years) with transient myocardial ischemia, suggesting that PWV is an indicator of increased cardiovascular risk. Although AIx is known to be associated with several cardiovascular diseases, it was not seen to be associated with silent myocardial ischemia. Our results suggest that the clinical significance of parameters of arterial stiffness and arterial wave reflection change with age, with a higher clinical importance of PWV indicated in patients over the age of 60.


Asunto(s)
Velocidad del Flujo Sanguíneo/fisiología , Presión Sanguínea/fisiología , Hipertensión/fisiopatología , Isquemia Miocárdica/fisiopatología , Anciano , Monitoreo Ambulatorio de la Presión Arterial , Arterias Carótidas/fisiopatología , Estudios de Casos y Controles , Elasticidad , Electrocardiografía , Femenino , Arteria Femoral/fisiopatología , Humanos , Hipertensión/complicaciones , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/etiología , Factores de Riesgo
17.
Artif Organs ; 30(8): 597-605, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16911313

RESUMEN

A multimodal treatment protocol with immunoadsorption (IA) as the central element was used in the treatment of myasthenic crisis (MC). Fifteen patients with MC were treated in repeated, uninterrupted 7-day cycles until mobilization with: (i) large-volume IA using an antihuman-IgG adsorber, days 1-5; (ii) intravenous immunoglobulin substitution (0.3-0.5 g/kg body weight [BW]/day), days 5-7; and (iii) immunosuppression with cyclophosphamide (1-2 mg/kg BW/day) and prednisolone (0.5-1 mg/kg BW/day), until remission. Patients required a median of 8 days of mechanical ventilation, 12 days in the intensive care unit, and 35 days of hospitalization. Functional improvement compared to their precrisis condition was attained by 14 of 15 patients. MG severity score improved by a mean of 10 points, quality of life score by 9.8 points, and Karnofsky index by 29 points in 14 of 15 patients. Improvements remained stable and no further crises occurred during long-term follow-up, which averaged 4.4 years. No fatalities due to MC occurred. The results demonstrate that our protocol is a potent therapeutic approach in the treatment of MC.


Asunto(s)
Anticuerpos Antiidiotipos/uso terapéutico , Inmunoglobulina G/inmunología , Inmunoadsorbentes/uso terapéutico , Miastenia Gravis/terapia , Insuficiencia Respiratoria/terapia , Adulto , Anciano , Anticuerpos Antiidiotipos/efectos adversos , Autoanticuerpos/sangre , Eliminación de Componentes Sanguíneos/efectos adversos , Eliminación de Componentes Sanguíneos/métodos , Terapia Combinada , Femenino , Hospitalización , Humanos , Inmunoglobulina G/efectos adversos , Inmunoglobulina G/uso terapéutico , Técnicas de Inmunoadsorción , Inmunoadsorbentes/efectos adversos , Inmunosupresores/efectos adversos , Inmunosupresores/uso terapéutico , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Examen Neurológico , Receptores Nicotínicos/inmunología , Resultado del Tratamiento
18.
Blood Press Monit ; 11(4): 173-82, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16810027

RESUMEN

INTRODUCTION: The objective of the present study was to investigate the prevalence, the risk factors, the hemodynamic triggering mechanisms, the circadian variability of ST segment depression (ST depression) and the effect of day and night fall in blood pressure on the prevalence of ST depression in hypertensive patients. MATERIALS AND METHODS: In a multicentric study in Germany, 1,244 CardioTens registrations (combined 24-h ambulatory blood pressure measurement/electrocardiography with ST segment triggering; Meditech, Budapest, Hungary) from patients with arterial hypertension were consecutively monitored and evaluated centrally at the University of Bonn. Inclusion criterion was treated or untreated arterial hypertension. The ST segment was measured in accordance with the "1 : 1 : 1 rule" (horizontal or descending ST depression by 1 mm, 1 min duration, 1 min interval from the previous episode). RESULTS: ST segment depression was observed in 250 (20.1%) patients; 90.3% of the transient ST-segment depression was silent (without angina pectoris). Ambulatory 24-h blood pressure measurement, but not office-based blood pressure measurement, was predictive for the occurrence of ST-segment depression. Risk factors for ST-segment depression were the Sokolow index > or =3.5 mV, smoking status, severity of coronary heart disease, use of diuretics, reduced left ventricular function, pulse pressure > or =60 mmHg and increase of double product (1,000 mmHg/min). A significant rise of the systolic/diastolic blood pressure (+8+ or -18/+7+ or -10 mmHg), of the heart rate (+12+ or -13/min) and of the double product (+2,471+ or -2,517 mmHg/min) was found during the transient ST depression as compared with the corresponding 24-h ambulatory blood pressure measurement mean values (P<0.0001 for all parameters specified). In most intermittent ST depressions, a rise of the double product was seen (n=789 episodes), and in the remaining 239 ST depressions, a fall of the double product was observed. ST depressions with fall of the double product showed a circadian distribution with a peak in the late evening. ST depression accompanied by a rise in double product showed two peaks (one in the early morning and one in the late evening). The prevalence of ST depression was significantly higher (28.6%) in extreme dippers than in dippers (18.2%), risers (21.8%) and non-dippers (19.6%). CONCLUSIONS: ST depressions have a high prevalence of 20.1% in hypertensive patients. Clinical predictors for the occurrence of ST-segment depression were classical risk factors and cardiac target organ damage. Office-based blood pressure measurement was not a useful measuring tool for forecasting the likelihood of ST-segment depression. ST depressions were triggered inter alia by variations of blood pressure and the heart rate. The circadian variability of the ST depressions is crucially affected by the pressure double product characteristics on which the ST depression is based.


Asunto(s)
Hipertensión/complicaciones , Isquemia Miocárdica/epidemiología , Anciano , Monitoreo Ambulatorio de la Presión Arterial , Ritmo Circadiano , Diástole , Electrocardiografía Ambulatoria , Femenino , Alemania/epidemiología , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/etiología , Isquemia Miocárdica/fisiopatología , Prevalencia , Factores de Riesgo , Sístole
19.
Arch Toxicol ; 80(10): 713-8, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16721595

RESUMEN

IGF2 and H19 are imprinted genes in normal human tissue, but many studies have observed a loss of imprinting (LOI) of these genes in tumors as an epigenetic alteration of the DNA, that leads to a biallelic expression predisposing cells to carcinogenesis and tumor growth. The aim of this study was to test the reliability of LightCycler-assisted Real-time PCR in detecting LOI of IGF2 and H19 in 39 patients with testicular germ cell tumors by comparing these results with the analysis generated by the golden standard restriction fragment length polymorphism (RFLP). With LightCycler-assisted Real-time PCR for IGF2 44% and for H19 49% of the patients were found to be heterozygous. This was consistent with the results obtained by RFLP, but surprisingly RFLP failed in more than 7% of the patients. In detecting LOI (for IGF2 in 41% and for H19 in 68% of the informative patients) the approach by RFLP was superior, since the results derived from LightCycler-assisted Real-time PCR showed reliable results in 76 and 10% of the samples concerning IGF2 and H19, respectively. Again, no discrepancy between the results obtained by the two methods occurred. In sum, LightCycler-assisted Real-time PCR is a sufficiently working approach for the rapid and reliable detection of heterozygosity of IGF2 or H19 gene and identification of LOI of IGF2 and thus may be helpful in conducting large epidemiological studies. However, for the identification of LOI of the H19 gene in this cohort it possesses only restrictive use.


Asunto(s)
Impresión Genómica , Proteínas/genética , ARN no Traducido/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Seminoma/genética , Neoplasias Testiculares/genética , Estudios de Cohortes , Regulación Neoplásica de la Expresión Génica , Heterocigoto , Humanos , Factor II del Crecimiento Similar a la Insulina , Masculino , Polimorfismo de Longitud del Fragmento de Restricción , Valor Predictivo de las Pruebas , Proteínas/análisis , ARN Largo no Codificante , ARN Mensajero/análisis , ARN no Traducido/análisis , Reproducibilidad de los Resultados , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Seminoma/química , Neoplasias Testiculares/química
20.
Rheumatol Int ; 26(3): 244-51, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16365755

RESUMEN

Synovial macrophages play an outstanding role in many rheumatic diseases. However, traditional serum-containing tissue-culture techniques hamper in vitro studies due to fibroblast activation not found in vivo. The objective of this study was to examine dissociated synovial cells in a macrophage-selective, serum-free tissue-culture medium. Osteoarthritis synovial tissue (n=11) was cultured in Iscove's Modified Dulbecco's Medium (IMDM) with 10% fetal bovine serum (FBS) and compared to a serum-free, insulin-supplemented medium. After 9-11 and 19-21 days in vitro, immunohistochemistry was performed for macrophage/lymphocyte markers and cell division. Cytokine profiles were determined by RT-PCR. In serum, cells with a bipolar morphology rapidly proliferated. Respectively, 14.34+/-12.94% and 13.25+/-12.66% expressed CD68 and HLA-DR. These markers further decreased after one passage. In serum-free medium, proliferation was infrequent, and cells with diverse morphologies expressed 83.10+/-6.80% and 55.03+/-6.88% CD68 and HLA-DR respectively. CD14 was rare, and lymphocytes were missing. Both cultures expressed interleukin-6 and interleukin-8. This novel serum-free method permits the culture of distinct CD68/HLA-DR associated phenotypes.


Asunto(s)
Medio de Cultivo Libre de Suero/química , Macrófagos/clasificación , Membrana Sinovial/citología , Anciano , Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Biomarcadores/química , Técnicas de Cultivo de Célula/métodos , Medio de Cultivo Libre de Suero/metabolismo , Femenino , Antígenos HLA-DR/metabolismo , Humanos , Inmunohistoquímica/métodos , Macrófagos/inmunología , Masculino , Microscopía de Contraste de Fase , Persona de Mediana Edad
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