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1.
Biomed Khim ; 64(1): 16-22, 2018 Jan.
Artículo en Ruso | MEDLINE | ID: mdl-29460830

RESUMEN

Exocytosis of myeloperoxidase (MPO) from activated neutrophils in the presence of the anionic polysaccharide heparin was studied. It was determined that the optimal concentration of heparin (0.1 u/ml), at which there is no additional activation of cells (absence of amplification of exocytosis of lysozyme contained in specific and azurophilic granules). It was found that after preincubation of cells with heparin (0.1 u/ml) the exocytosis of MPO from neutrophils activated by various stimulants (fMLP, PMA, plant lectins CABA and PHA-L) increased compared to that under the action of activators alone. In addition, it was shown that heparin in the range of concentrations 0.1-50 u/ml did not affect on the peroxidase activity of the MPO isolated from leukocytes. Thus, the use of heparin at a concentration of 0.1 u/ml avoids the artifact caused by the "loss" of MPO in a result of its binding to neutrophils, and increases the accuracy of the method of registration the degranulation of azurophilic granules of neutrophils based on determination of the concentration or peroxidase activity of MPO in cell supernatants.


Asunto(s)
Exocitosis , Neutrófilos , Gránulos Citoplasmáticos , Heparina , Peroxidasa
2.
Biochem Cell Biol ; 96(4): 457-467, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29370542

RESUMEN

CP is a copper-containing ferroxidase of blood plasma, which acts as an acute phase reactant during inflammation. The effect of oxidative modification of CP induced by oxidants produced by MPO, such as HOCl, HOBr, and HOSCN, on its spectral, enzymatic, and anti-inflammatory properties was studied. We monitored the chemiluminescence of lucigenin and luminol along with fluorescence of hydroethidine and scopoletin to assay the inhibition by CP of the neutrophilic respiratory burst induced by PMA or fMLP. Superoxide dismutase activity of CP and its capacity to reduce the production of oxidants in respiratory burst of neutrophils remained virtually unchanged upon modifications caused by HOCl, HOBr, and HOSCN. Meanwhile, the absorption of type I copper ions at 610 nm became reduced, along with a drop in the ferroxidase and amino oxidase activities of CP. Likewise, its inhibitory effect on the halogenating activity of MPO was diminished. Sera of either healthy donors or patients with Wilson disease were co-incubated with neutrophils from healthy volunteers. In these experiments, we observed an inverse relationship between the content of CP in sera and the rate of H2O2 production by activated neutrophils. In conclusion, CP is likely to play a role of an anti-inflammatory factor tempering the neutrophil respiratory burst in the bloodstream despite the MPO-mediated oxidative modifications.


Asunto(s)
Ceruloplasmina/farmacología , Neutrófilos/efectos de los fármacos , Peroxidasa/efectos de los fármacos , Estallido Respiratorio/efectos de los fármacos , Ceruloplasmina/metabolismo , Humanos , Peróxido de Hidrógeno/metabolismo , Neutrófilos/metabolismo , Oxidación-Reducción/efectos de los fármacos , Peroxidasa/metabolismo
3.
Bull Exp Biol Med ; 161(4): 495-500, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27597056

RESUMEN

Myeloperoxidase, heme enzyme of azurophilic granules in neutrophils, is released into the extracellular space in the inflammation foci. In neutrophils, it stimulates a dose-dependent release of lactoferrin (a protein of specific granules), lysozyme (a protein of specific and azurophilic granules), and elastase (a protein of azurophilic granules). 4-Aminobenzoic acid hydrazide, a potent inhibitor of peroxidase activity of myeloperoxidase, produced no effect on neutrophil degranulation. Using signal transduction inhibitors (genistein, methoxyverapamil, wortmannin, and NiCl2), we demonstrated that myeloperoxidase-induced degranulation of neutrophils resulted from enzyme interaction with the plasma membrane and depends on activation of tyrosine kinases, phosphatidylinositol 3-kinases (PI3K), and calcium signaling. Myeloperoxidase modified by oxidative/halogenation stress (chlorinated and monomeric forms of the enzyme) lost the potency to activate neutrophil degranulation.


Asunto(s)
Neutrófilos/metabolismo , Peroxidasa/metabolismo , Ácido 4-Aminobenzoico/farmacología , Androstadienos/farmacología , Señalización del Calcio/efectos de los fármacos , Degranulación de la Célula/efectos de los fármacos , Células Cultivadas , Galopamilo/farmacología , Genisteína/farmacología , Células HL-60 , Humanos , Neutrófilos/efectos de los fármacos , Níquel/farmacología , Estrés Oxidativo/efectos de los fármacos , Peroxidasa/antagonistas & inhibidores , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal/efectos de los fármacos , Wortmanina
4.
Biomed Khim ; 62(3): 318-24, 2016 Mar.
Artículo en Ruso | MEDLINE | ID: mdl-27420626

RESUMEN

A significant increase in the myeloperoxidase (MPO) activity has been found in plasma of patients with stable angina and with acute coronary syndrome (ACS) in comparison with the control group. MPO concentration was significantly increased in plasma of ACS patients. Reduced MPO activity in the treated ACS patients correlated with a favorable outcome of the disease. Generally, changes in plasma MPO concentration coincided with changes in lactoferrin concentration thus confirming the role of neutrophil degranulation in the increase of plasma concentrations of these proteins. The increase in MPO activity was obviously determined by modification of the MPO protein caused by reactive oxygen species and halogen in the molar ratio of 1 : 25 and 1 : 50. The decrease in plasma MPO activity may be associated with increased plasma concentrations of the physiological inhibitor of its activity, ceruloplasmin, and also with modification of the MPO protein with reactive oxygen species and halogen at their molar ratio of 1 : 100 and higher. Thus, MPO activity may be used for evaluation of effectiveness of the treatment of cardiovascular diseases.


Asunto(s)
Síndrome Coronario Agudo/sangre , Angina Estable/sangre , Peroxidasa/sangre , Síndrome Coronario Agudo/patología , Angina Estable/patología , Biomarcadores/sangre , Estudios de Casos y Controles , Ceruloplasmina/metabolismo , Femenino , Humanos , Lactoferrina/sangre , Masculino , Persona de Mediana Edad
5.
Biofizika ; 60(1): 120-8, 2015.
Artículo en Ruso | MEDLINE | ID: mdl-25868349

RESUMEN

Effects of water-soluble phenolic antioxidant sodium 3-(3'-tret-butyl-4'-hydroxyphenyl)-propyl thiosulfonate (TS-13), potassium 3,5-dimethyl-4-hydroxybenzyl thioetanoate (BEP-11-K) and potassium 3-(3',5'-ditretbutyl-4'-hydroxyphenyl)-propionate (potassium phenosan) on tumor cells proliferative activity and the role of redox-dependent and calcium-dependent signaling mechanisms in realization of tumor cell response to the antioxidant action were studied. Potassium phenosan and BEP-11-K were found to stimulate proliferation and ARE-inducing phenolic antioxidant TS-13 was found to inhibit tumor cell growth in culture. The tumor cell growth rate depended on the rate of intracellular reactive oxygen species production and was decreased by apocynin (a NADPH-oxidase inhibitor) and antimycin A (an ubiquinol-cytochrome c oxidoreductase inhibitor). TS-13 action on tumor cells was accompanied by a transient increase in intracellular reactive oxygen species production and the intracellular calcium concentration, whereas cell incubation with potassium phenosan and BEP-11-K did not influence the reactive oxygen species level and intracellular calcium ions. Cyclosporine A blocked the inhibitory effect of TS-13. Thus, it can be reasonably speculated that phenolic antioxidant TS-13 starts mitochondria-dependent apoptosis in tumor cells by the opening of permeability transition pores.


Asunto(s)
Antioxidantes/farmacología , Apoptosis/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Mitocondrias/metabolismo , Elementos de Respuesta , Ácidos Tiosulfónicos/farmacología , Línea Celular Tumoral , Humanos , Mitocondrias/patología , NADPH Oxidasas/antagonistas & inhibidores , NADPH Oxidasas/metabolismo , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/metabolismo , Neoplasias , Especies Reactivas de Oxígeno/metabolismo
6.
Bull Exp Biol Med ; 155(1): 118-21, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23667888

RESUMEN

We described a spectrophotometric method for measuring hemoglobin peroxidase activity in human plasma using o-dianisidine (o-DA) as the substrate and myeloperoxidase specific inhibitor 4-aminobensoic acid hydrazide (ruling out the probable contribution of myeloperoxidase to the measured parameter value). The optimal conditions (pH 5.5; 2 mM H2O2) have been determined, at which hemoglobin makes the main contribution to plasma oxidation of o-DA. A significant positive correlation between hemoglobin peroxidase activity measured by the spectrophotometric method and hemoglobin level measured by the pyridine hemochromogenic method has been detected (r=0.624; p<0.01) in plasma specimens from 16 donors. Plasma hemoglobin peroxidase activities were measured in healthy individuals and patients with type 2 diabetes mellitus and coronary heart disease. High plasma hemoglobin peroxidase activities in both groups of patients indicates disorders in the mechanisms of clearance of hemoglobin and its highly reactive derivatives and can serve as specific markers of diseases associated with oxidative stress.


Asunto(s)
Enfermedad Coronaria/enzimología , Diabetes Mellitus Tipo 2/enzimología , Hemoglobinas/metabolismo , Peroxidasa/sangre , Ácido 4-Aminobenzoico/química , Biomarcadores/sangre , Enfermedad Coronaria/sangre , Diabetes Mellitus Tipo 2/sangre , Dianisidina/química , Humanos , Estrés Oxidativo
7.
Biofizika ; 58(4): 681-9, 2013.
Artículo en Ruso | MEDLINE | ID: mdl-24455888

RESUMEN

It is shown that human serum albumin, previously treated with HOCl (HSA-Cl), enhances luminol-dependent chemiluminescence of neutrophils activated by phorbol-12-myristate-13-acetate (PMA). The enzyme-linked immunosorbent assay revealed that addition of HSA-Cl to neutrophils promotes exocytosis of myeloperoxidase. Inhibitor of myeloperoxidase--4-aminobenzoic acid hydrazide, without any effect on lucigenin-dependent chemiluminescence of neutrophils stimulated with PMA, effectively suppressed luminol-dependent chemiluminescence (IC50 = 20 microM) under the same conditions. The transfer of the cells from medium with HSA-Cl and myeloperoxidase to fresh medium abolished an increase in PMA-induced luminol-dependent chemiluminescence, but not the ability of neutrophils to respond to re-addition of HSA-Cl. A direct and significant (r = 0.75, p) correlation was observed between the intensity of PMA stimulated neutrophil chemiluminescence response and myeloperoxidase activity in the cell-free media after chemiluminescence measurements. These results suggest the involvement of myeloperoxidase in the increase of neutrophil PMA-stimulated chemiluminescence response in the presence of HSA-Cl. A significant positive correlation was found between myeloperoxidase activity in blood plasma of children with severe burns and the enhancing effects of albumin fraction of the same plasma on luminol-dependent chemiluminescence of PMA-stimulated donor neutrophils. These results support a hypothesis that proteins modified in reactions involving myeloperoxidase under oxidative/halogenative stress, stimulate neutrophils, leading to exocytosis of myeloperoxidase, a key element of halogenative stress, and to closing a "vicious circle" of neutrophil activation at the inflammatory site.


Asunto(s)
Quemaduras/enzimología , Luminol/química , Neutrófilos/efectos de los fármacos , Peroxidasa/metabolismo , Albúmina Sérica/farmacología , Compuestos de Anilina/farmacología , Quemaduras/patología , Niño , Inhibidores Enzimáticos/farmacología , Ensayo de Inmunoadsorción Enzimática , Humanos , Ácido Hipocloroso/química , Luminiscencia , Mediciones Luminiscentes , Activación Neutrófila/efectos de los fármacos , Neutrófilos/enzimología , Neutrófilos/metabolismo , Neutrófilos/patología , Estrés Oxidativo , Peroxidasa/antagonistas & inhibidores , Ésteres del Forbol/farmacología , Albúmina Sérica/química
8.
Biofizika ; 57(1): 93-8, 2012.
Artículo en Ruso | MEDLINE | ID: mdl-22567914

RESUMEN

It is shown that in the presence of reduced glutathione at low concentrations (1-5 microM) the extent of platelet aggregation with neutrophils increases and the lag period of platelet aggregation induced by tumor cells decreases. At the same time in the presence of reduced glutathione at high concentration (3 mM) the extent of platelet aggregation with neutrophils decreases, and the lag period of platelet aggregation induced by tumor cells increases. It is established that glutathione-dependent regulation of the intercellular contact formation between platelets and neutrophils depends on the ratio of glutathione oxidized and reduced forms: at fixed total glutathione concentration of 5 microM, increase of glutathione redox potential from -175 mV to 0 mV led to reduction in platelet aggregation with neutrophils. Thus, it is shown for the first time, that GSH has priming effect on the platelet aggregation with neutrophils and tumor cells, which may contribute to the regulation of inflammatory diseases and cancer.


Asunto(s)
Plaquetas/efectos de los fármacos , Comunicación Celular/efectos de los fármacos , Disulfuro de Glutatión/farmacología , Glutatión/farmacología , Neutrófilos/efectos de los fármacos , Plaquetas/citología , Plaquetas/metabolismo , Relación Dosis-Respuesta a Droga , Células HeLa , Humanos , Neutrófilos/citología , Neutrófilos/metabolismo , Oxidación-Reducción , Agregación Plaquetaria/efectos de los fármacos , Estallido Respiratorio/efectos de los fármacos , Espectrofotometría
9.
Biomed Khim ; 58(4): 475-84, 2012.
Artículo en Ruso | MEDLINE | ID: mdl-23413692

RESUMEN

Using previously developed spectro-photonmetrical method (Bioorg. Khim. 2009. V. 35. pp. 629-639), a significant increase of myeloperoxidase (MPO) activity was found in blood plasma of patients with type 2 diabetes mellitus (DM2) without of cardiovascular complications, as well as with ischemic heart disease (IHD). Plasma MPO concentration measured by an enzyme-linked immunosorbent assay was significantly higher only in blood plasma of patient with DM2 and IHD. A direct and significant correlation between MPO activity and MPO concentration was observed only in blood plasma samples from healthy donors. Increased MPO activity did not correlate with MPO concentration in blood plasma of patients with DM2 and DM2 with IHD. Taken together, these results highlight the necessity for studying of the MPO role in the development of pathological processes to determine both the amount of enzyme and its peroxidase activity in the blood. The proposed approach gives comprehensive information about the relationship between MPO activity and MPO concentration in patient blood. Since the high concentration of MPO is a diagnostically significant parameter in the prediction of endothelial dysfunction and cardiovascular disease development, the obtained results evidence the contribution of MPO-dependent reactions in cardiovascular complications associated with diabetes. MPO activity may serve as an additional diagnostic criterion for determination of risk of IHD in DM patients.


Asunto(s)
Complicaciones de la Diabetes/sangre , Diabetes Mellitus Tipo 2/sangre , Isquemia Miocárdica/sangre , Peroxidasa/sangre , Adulto , Complicaciones de la Diabetes/diagnóstico , Diabetes Mellitus Tipo 2/diagnóstico , Endotelio Vascular/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/etiología , Factores de Riesgo
10.
Bull Exp Biol Med ; 154(1): 23-6, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23330081

RESUMEN

We performed a comparative analysis of functional activity of neutrophils in patients with type 2 diabetes mellitus with and without symptoms of CHD. Enhanced H2O2 production by neutrophils in response to N-formyl-Met-Leu-Phe (fMLP) was found in patients with type 2 diabetes mellitus. In patients with type 2 diabetes mellitus associated with CHD, fMLP-induced release of myeloperoxidase from azurophilic granules of neutrophils was reduced and plasma myeloperoxidase level was elevated. Increased peroxidase activity of myeloperoxidase, reduced plasma catalase activity, and increased levels of TBA-reactive lipid peroxidation products and oxidized glutathione were detected in patients of both groups. Since myeloperoxidase is an important neutrophilic mediator of oxidative stress, its increased activity in the blood can be an additional marker of oxidative stress and cardiovascular risk in patients with diabetes mellitus.


Asunto(s)
Enfermedad Coronaria/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , N-Formilmetionina Leucil-Fenilalanina/análogos & derivados , Neutrófilos/metabolismo , Peroxidasa/metabolismo , Catalasa/metabolismo , Activación Enzimática , Glutatión/metabolismo , Humanos , Peróxido de Hidrógeno/metabolismo , Persona de Mediana Edad , N-Formilmetionina Leucil-Fenilalanina/farmacología , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo
11.
Biofizika ; 56(3): 465-74, 2011.
Artículo en Ruso | MEDLINE | ID: mdl-21786700

RESUMEN

A model for the redox regulation of the functional state of the cell has been constructed on the basis of representation of electron transfer processes by equivalent electric circuits. The mechanism of action of redox active molecules on biosystems has been discussed in terms of circuit theory. A method for determining the parameters of cellular redox sensors has been proposed. It has been established that the concentration and redox potential of compounds entering the cell are the main regulatory parameters of redox signals for the cell. It has been experimentally shown that the calcium response to hydrogen peroxide in rat C6 glioma cells and human FL amnion cells depends on the redox buffer capacity of cells.


Asunto(s)
Señalización del Calcio/efectos de los fármacos , Peróxido de Hidrógeno/farmacología , Modelos Biológicos , Oxidantes/farmacología , Estrés Oxidativo/efectos de los fármacos , Animales , Línea Celular Tumoral , Humanos , Oxidación-Reducción/efectos de los fármacos , Ratas
12.
Biofizika ; 56(2): 265-71, 2011.
Artículo en Ruso | MEDLINE | ID: mdl-21542356

RESUMEN

The effect of NO donors (sodium nitroprusside, S-nitrosoglutathione, dinitrosyl-iron complexes) on the functional and mechanical properties of human platelets and red blood cells has been investigated. It has been established by atomic force microscopy that NO donor-induced platelet disaggregation is accompanied by changes in the elastic properties of cells. It has been shown that, in the presence of NO donors, the detergent-induced hemolysis of red blood cells is delayed, and the elasticity modulus of these cells decreases. The results obtained indicate that NO donors regulate the structural and functional properties of platelets and red blood cells.


Asunto(s)
Plaquetas/metabolismo , Eritrocitos/metabolismo , Donantes de Óxido Nítrico/farmacología , Plaquetas/ultraestructura , Detergentes/farmacología , Elasticidad/efectos de los fármacos , Eritrocitos/ultraestructura , Hemólisis/efectos de los fármacos , Humanos , Microscopía de Fuerza Atómica/métodos
13.
Bull Exp Biol Med ; 150(3): 372-4, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21240357

RESUMEN

We studied the effect of dinitrosyl iron complexes with glutathione ligands on platelet aggregation with HeLa tumor cells. It was shown that dinitrosyl iron complexes not only inhibited cell aggregation, but being added at early stages can also block this process. These findings dictate further studies of dinitrosyl iron complexes as a compound reducing metastasizing and thrombus-formation in tumor patients.


Asunto(s)
Hierro/farmacología , Metástasis de la Neoplasia/prevención & control , Óxidos de Nitrógeno/farmacología , Agregación Plaquetaria/efectos de los fármacos , Neoplasias del Cuello Uterino/metabolismo , Femenino , Glutatión/metabolismo , Células HeLa , Humanos , Hierro/metabolismo , Microscopía , Óxido Nítrico/metabolismo , Óxidos de Nitrógeno/metabolismo
14.
Tsitologiia ; 51(10): 824-9, 2009.
Artículo en Ruso | MEDLINE | ID: mdl-19950861

RESUMEN

We investigated the influence ofneopterin and 7, 8-dihydroneopterin on the activity and secretory degranulation of myeloperoxidase in neutrophils and the ability of pteridines to interact with the main substrate of this enzyme, hydrogen peroxide, and with the intermediate product of halogenation cycle--hypochlorous acid. It was shown that neopterin and 7, 8-dihydroneopterin while being a redox-pair regulated the process of oxygen activation in neutrophils by functioning of myeloperoxidase. Depending on concentration, pteridines can influence the secretion of myeloperoxidase into intracellular medium and decrease the level of hydrogen peroxide and hypochlorous acid that are a substrate and an intermediate product of the enzyme respectively. It was shown that 7, 8-dihydroneopterin in micromolar concentration appeared to be noncompetitive inhibitor of myeloperoxidase. We suppose that myeloperoxidase assists 7, 8-dihydroneopterin oxidation by hypochlorous acid that leads to neopterin concentration increase. These changes modify the concentration of reactive oxygen species in intracellular and extracellular media.


Asunto(s)
Neopterin/análogos & derivados , Neopterin/metabolismo , Neutrófilos/enzimología , Peroxidasa/metabolismo , Relación Dosis-Respuesta a Droga , Humanos , Peróxido de Hidrógeno/metabolismo , Ácido Hipocloroso/metabolismo , Neopterin/farmacología , Neutrófilos/efectos de los fármacos , Oxidación-Reducción/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo
15.
Bioorg Khim ; 35(5): 629-39, 2009.
Artículo en Ruso | MEDLINE | ID: mdl-19915640

RESUMEN

A novel method for spectrometrical measurement of myeloperoxidase (MPO) activity in plasma with o-dianisidine (DA) as a substrate is proposed. We have determined the optimal conditions, including the pH and hydrogen peroxide concentration, under which MPO is the main contributor to DA oxidation in plasma. Specific MPO inhibitors, salicylhydroxamic acid or (4-aminobenzoyl)hydrazide, are added to measure the activity of other heme-containing peroxidases (mainly hemoglobin and its derivatives) and subtract their contribution from the total plasma peroxidase activity. Plasma MPO concentrations are quantified by a new enzyme-linked immunosorbent assay (ELISA) developed by us and based on the use of antibodies raised in rats and rabbits. The sensitivity of this ELISA is high: 0.2-250 ng/ml. A direct and significant (P < 0.0001) correlation was observed between the MPO activities measured spectrometrically and by ELISA in blood samples from 38 healthy donors. The proposed approaches to MPO measurement in plasma can be used to evaluate the enzyme activity and concentration, as well as the efficacy of mechanisms by which MPO is regulated under physiological conditions and against the background of various inflammatory diseases.


Asunto(s)
Dianisidina/química , Peróxido de Hidrógeno/química , Peroxidasa/sangre , Animales , Inhibidores Enzimáticos/química , Ensayo de Inmunoadsorción Enzimática , Humanos , Concentración de Iones de Hidrógeno , Inflamación/sangre , Inflamación/enzimología , Conejos , Ratas , Sensibilidad y Especificidad
16.
Biofizika ; 54(5): 846-51, 2009.
Artículo en Ruso | MEDLINE | ID: mdl-19894624

RESUMEN

The parameters of the acid-base state and redox state of erythrocytes have been studied with the use of the fluorescent probes 2',7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein and 2',7'-dichlorodihydrofluorescein. It has been found that the value of redox state parameters in erythrocytes depends both on the extracellular and intracellular concentrations of hydrogen ions. It has been shown that hydrogen peroxide induces a decrease in the value of the intracellular pH. The interrelation of cellular homeostasis parameters characterizing the acid-base and redox states of erythrocytes has been theoretically and experimentally substantiated.


Asunto(s)
Eritrocitos/química , Colorantes Fluorescentes/química , Hidrógeno/química , Cationes Monovalentes/química , Humanos , Concentración de Iones de Hidrógeno , Oxidación-Reducción
17.
Bull Exp Biol Med ; 147(4): 469-72, 2009 Apr.
Artículo en Inglés, Ruso | MEDLINE | ID: mdl-19704951

RESUMEN

Effects of ascorbic acid on calcium homeostasis of human laryngeal carcinoma cells were studied. Intracellular concentration of free calcium and intracellular pH were measured by fluorescent analysis. Ascorbic acid in concentrations of 3-10 mM caused pH drop and sharply increased concentrations of free Ca ions in HEp-2 cells. Intracellular concentration of free Ca ions resulted from Ca ion release from the thapsigargin-sensitive Ca depots.


Asunto(s)
Antioxidantes/farmacología , Ácido Ascórbico/farmacología , Señalización del Calcio/efectos de los fármacos , Calcio/metabolismo , Carcinoma/tratamiento farmacológico , Neoplasias Laríngeas/tratamiento farmacológico , Antioxidantes/administración & dosificación , Ácido Ascórbico/administración & dosificación , Carcinoma/metabolismo , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/farmacología , Espacio Extracelular/efectos de los fármacos , Fluorescencia , Humanos , Peróxido de Hidrógeno/farmacología , Concentración de Iones de Hidrógeno , Espacio Intracelular/efectos de los fármacos , Espacio Intracelular/metabolismo , Neoplasias Laríngeas/metabolismo , Oxidantes/farmacología , Tapsigargina/farmacología , Factores de Tiempo
18.
Ukr Biokhim Zh (1999) ; 81(6): 85-93, 2009.
Artículo en Ruso | MEDLINE | ID: mdl-20387662

RESUMEN

It has been shown by the method of fluorescent analysis that the rate of hydrogen peroxide generation in human U251 glioma cells under the effect of lipophilic (menadione) or hydrophilic (vikasol) analogues of vitamin K3 was different. Analyzing experimental data we can conclude that menadione underwent one- and two-electron reduction by intracellular reductases in glioma cells. Reduced forms of menadione interact with molecular oxygen leading to reactive oxygen species (ROS) generation. The theoretical model of ROS generation including two competitive processes of one- and two-electron reduction of menadione has been proposed. Rate constants of ROS generation mediated by one-electron reduction process have been estimated.


Asunto(s)
Antineoplásicos/farmacología , Especies Reactivas de Oxígeno/metabolismo , Vitamina K 3/farmacología , Antineoplásicos/química , Antineoplásicos/metabolismo , Benzoquinonas/farmacología , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Glioma/metabolismo , Glioma/patología , Humanos , Peróxido de Hidrógeno/metabolismo , Modelos Biológicos , Oxidación-Reducción , Vitamina K 3/química , Vitamina K 3/metabolismo
19.
Usp Fiziol Nauk ; 39(3): 29-44, 2008.
Artículo en Ruso | MEDLINE | ID: mdl-19062544

RESUMEN

Recent achievements of biophysics and physiology resulted to remarkable progress in the understanding of role of redox processes in cell vital function. It was established that oxidizing and reducing agents participate in processes of differentiation, proliferation and apoptosis. Representations about an existence of definite balance between oxidation and reduction processes in cells or a redox homeostasis were formed. Recent data about mechanisms of regulation of redox homeostasis were considered in the review. The correlation between redox homeostasis and metabolism were in detail analyzed. The special interest is given to a problem of quantitative description of redox phenomena in biological systems.


Asunto(s)
Fenómenos Fisiológicos Celulares , Homeostasis/fisiología , Oxidación-Reducción , Animales , Humanos
20.
Bull Exp Biol Med ; 145(1): 99-103, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19024015

RESUMEN

The morphology and structure of erythrocyte cytoskeleton and local mechanical characteristics in patients with type 2 diabetes mellitus and donors were studied by atomic force microscopy. Poikilocytosis and anisocytosis, spatial reorganization of the cytoskeleton (loosening and condensation of the actin-spectrin network), and modification of local mechanical properties of erythrocytes were characteristic of diabetics. These results indicate significant heterogeneity of erythrocyte population in the patients, most likely due to the presence of erythrocytes of different age groups, which can promote the development of diabetes complications (angiopathy).


Asunto(s)
Diabetes Mellitus Tipo 2/sangre , Membrana Eritrocítica , Eritrocitos , Anciano , Citoesqueleto/química , Citoesqueleto/metabolismo , Elasticidad , Deformación Eritrocítica , Membrana Eritrocítica/química , Membrana Eritrocítica/metabolismo , Eritrocitos/citología , Eritrocitos/metabolismo , Humanos , Microscopía de Fuerza Atómica , Persona de Mediana Edad , Propiedades de Superficie , Adulto Joven
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