RESUMEN
As a result of experiments carried out on adult (6-8 months) and old (24-26 months) male rats of the Wistar line it is established that emotional-pain stress results (in one day) in essential increase in the activity of spontaneous, NADPH--and ascorbate-dependent peroxidation of lipids in the liver microsomes, which is expressed in the old animals rather than in the adult ones. The induced peroxidation of lipid six days after the stress effect remains activated in the adult rats and decreases to the control level in the old ones. Accumulation of lipoperoxidation products in the membrane structure of hepatocytes is accompanied by the changes of physico-chemical parameters of microsomal membranes, microviscosity and surface potential in particular. Availability of conformational shifts of membrane proteins of microsomes under the conditions of lipoperoxidation activation evoked by the stress is accompanied by changes of physico-chemical parameters of microsomal membranes. Changes in the membrane structure are expressed to the less extent in the microsomes of old rats liver as well, that evidences for the age-dependent differences of adaptational capacities of the organism.
Asunto(s)
Envejecimiento/metabolismo , Retículo Endoplásmico/metabolismo , Peroxidación de Lípido/fisiología , Hígado/metabolismo , Estrés Fisiológico/metabolismo , Adaptación Fisiológica , Animales , Fenómenos Químicos , Química Física , Masculino , Membranas/metabolismo , Microsomas Hepáticos/metabolismo , Ratas , Ratas WistarRESUMEN
Results obtained from the study of the interaction between the phytosteroid preparation (BTK-8L) and fractionated rat liver nuclear chromatin under conditions of the tetrachloromethane and chlorophos intoxications are described. It is shown that preventive injection of BTK-8L to the animals has a partial protective effect on transcriptionally active and repressed liver chromatin. This preparation interacts with chromatin histone proteins binding with them and changes the nucleoprotein complex structure as a results of which the chromatin fraction components become less accessible to the damaging action of tetrachloromethane and chlorophos. The BTK-8L protective effect is exhibited on the DNA replication and transcriptional levels under conditions of tetrachloromethane and chlorophos intoxications.
Asunto(s)
Antioxidantes/uso terapéutico , Intoxicación por Tetracloruro de Carbono/tratamiento farmacológico , Cromatina/efectos de los fármacos , Esteroides/uso terapéutico , Triclorfón/envenenamiento , Animales , Proteínas Cromosómicas no Histona/efectos de los fármacos , ADN/efectos de los fármacos , Etidio , Colorantes Fluorescentes , Histonas/efectos de los fármacos , Masculino , Ratas , Ratas Wistar , Transcripción Genética/efectos de los fármacosRESUMEN
Results of the study of interaction of the phytoecdysteroid preparation (BTK-8L) with fractionated rat liver nuclear chromatin were described. It was shown that the interaction resulted in the "loosening" of the histone proteins structure both in active and repressed chromatin. At the same time the reparative DNA synthesis in the repressed fraction was stimulated. The Change revealed might be the basis of protective properties of BTK-8L as to chromatin at chloro and organophosphorus intoxications.
Asunto(s)
Cromatina/metabolismo , Hígado/efectos de los fármacos , Esteroides/farmacología , Animales , ADN/efectos de los fármacos , Hígado/metabolismo , Masculino , Conformación de Ácido Nucleico , Conformación Proteica , Ratas , Ratas WistarRESUMEN
Structural and functional state of rat hepatocytes endoplasmic reticulum membranes intoxicated with chlorofos (0,0-dimethyl-(1-oxy-2,2,21-trichloroethylphosphonate) was studied. It was shown that in case of intoxication a breakage of the membrane Ca(2+)-transport function was accompanied by modification of the membrane phospholipid lipoperoxidation processes and by conformational change of proteins. It is established that prophylactic injection of m-cholinolytic atropine and Ca(2+)-channel antagonist verapamil lead to normalization of processes of ATP-dependent potassium ion transport and lipid peroxidation processes (LPO) in the liver microsomal membranes of intoxicated animals.
Asunto(s)
Atropina/farmacología , Calcio/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Microsomas Hepáticos/efectos de los fármacos , Triclorfón/envenenamiento , Verapamilo/farmacología , Animales , Antídotos/farmacología , Membrana Celular/efectos de los fármacos , Femenino , Transporte Iónico/efectos de los fármacos , Malondialdehído/metabolismo , Microsomas Hepáticos/metabolismo , Conformación Proteica , Ratas , Ratas Wistar , Relación Estructura-ActividadRESUMEN
Genoprotective effect of preparation BTK-8L from plant steroids at prophylactic injection to experimental animals at chromatin damage by chlorofos was revealed. Antioxidant action of the preparation, being most highly expressed in the transcriptionally active chromatin fraction, is, probably, the most likely mechanism of the action. The realization of this action might be carried out as a result of the direct binding of BTK-8L with the chromatin protein-lipid complex, which was revealed during the analysis of the model systems showing binding of the preparation with chromatin fractions in vitro. Correction of structural chromatin organization and its transcriptional activity modified with intoxication of animals by chlorofos may occur as a result of such binding. Genoprotective properties in BTK-8L correlate to some extent with the lowering of the death rate of experimental animals at the early stage of intoxication by chlorofos at the prophylactic injection of the preparation, which, nevertheless, was not so significant, as in the case of intoxication by tetrachloromethane. Such fact allowed suggesting the existence of delayed unfavourable consequences for the organism (mutagenesis, cancerogenesis) as a result of the realization of the genotoxic action of chlorofos.
Asunto(s)
Antimutagênicos/farmacología , Antioxidantes/farmacología , Cromatina/efectos de los fármacos , Plantas Medicinales , Esteroides/farmacología , Triclorfón/antagonistas & inhibidores , Animales , Intoxicación por Tetracloruro de Carbono/prevención & control , Masculino , Ratas , Ratas Wistar , Transcripción Genética/efectos de los fármacos , Triclorfón/envenenamientoRESUMEN
Hepatoprotective action of prophylactic injection of aqueous solution of preparation BTK-8L from plant ecdysteroids to experimental animals with the liver damage by tetrachloromethane was revealed. This effect at least partially was connected with the genoprotective action of the given preparation. As a result, normalization of free radical chromatin lipid peroxidation reaction, modified at the intoxication, as well as partial correction of physical and chemical properties of chromatin protein-lipid complex were those molecular mechanisms of genoprotective action of BTK-8L, which were manifested by the influence of the preparation on such indices which characterized the depth structure of the complex as microviscosity and energy transfer from the protein to the lipid probe. Investigation of the interaction of the preparation with chromatin fractions in vitro and comparison of this interaction with the analogous process in model systems allowed revealing determinative participation of chromatin proteins and lipids in the given process. The preparation interacted more intensively with the active chromatin fraction, which contained a more marked protein-lipid complex, as comparing to the repressed one. Injection of the preparation also normalized such indices as relation between the chromatine fractions and protein/DNA ratio in them. On the contrary, injection of the alcoholic solution of the preparation to experimental animals, aggravated genotoxic tetrachloromethane action.
Asunto(s)
Antimutagênicos/farmacología , Intoxicación por Tetracloruro de Carbono/prevención & control , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Cromatina/efectos de los fármacos , Esteroides/farmacología , Animales , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Radicales Libres , Genoma , Peroxidación de Lípido/efectos de los fármacos , Masculino , Plantas Medicinales , Ratas , Ratas WistarRESUMEN
Enzymatic activity and structural peculiarities of human erythrocyte membranes obtained by different methods, are analyzed in the paper. Our studies have demonstrated different enzymatic activity of the preparations of right side- and inside-out vesicles of human erythrocyte membranes. Fluorescence probes of pyrene and ANS have shown that these membrane preparations have different physical characteristics of lipid and conformational properties of membrane proteins and differ in the composition of their protein-lipid ensembles.
Asunto(s)
Membrana Eritrocítica/enzimología , Membrana Eritrocítica/ultraestructura , Colorantes Fluorescentes , Humanos , Lípidos de la Membrana/química , Proteínas de la Membrana/química , Conformación ProteicaRESUMEN
Marked changes in the structural and functional characteristics of liver nuclear chromatin fractions are observed under experimental D-hypovitaminosis, which differ in the degree of transcriptional activity. DNA-polymerase activity and activity of the fraction, enriched with RNA-polymerase I, increases in the active fraction. Free radical LPO reactions are modified in the chromatin fraction with low activity and to the less degree in the active one. Disturbances of chromatine structural properties are caused with the change in the protein and lipid components of chromatin. Administration of ecdysterone preparations (separately and together with vitamin D3) has a partial corrective effect on structural and functional organization of nuclear chromatine. At the action of ecdysterone normalization of LPO reactions modified by pathological changes is observed in the chromatin fraction with low activity and to the less degree in the active one. This kind of influence corrects to the less degree chromatin functional activity and quantitative and qualitative modifications of its protein component. Simultaneous influence of ecdysterone and vitamin D3 leads to the partial normalization of the biochemical indices studied (except for those which characterize LPO reactions) mainly in the active chromatin fraction.
Asunto(s)
Colecalciferol/farmacología , Cromatina/química , Ecdisterona/farmacología , Hígado/química , Deficiencia de Vitamina D/metabolismo , Animales , Fraccionamiento Químico , ADN Polimerasa Dirigida por ADN/efectos de los fármacos , ADN Polimerasa Dirigida por ADN/metabolismo , ARN Polimerasas Dirigidas por ADN/efectos de los fármacos , ARN Polimerasas Dirigidas por ADN/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Hígado/efectos de los fármacos , Masculino , Ratas , Ratas Wistar , Relación Estructura-Actividad , Transcripción GenéticaRESUMEN
Structural modification of transcriptionally active and repressed rat liver chromatin fractions at antioxidant insufficiency caused by E-avitaminosis, was shown. This modification consisted in the compactization of the first fraction structure and in the relaxation of the second one. Besides, compactization of the active fraction structure was accompanied with the increase of fluidity of the lipid bilayer. On the whole antioxidant insufficiency caused more expressed structural changes in the active chromatin fraction, this correlated with the intensity of lipid peroxidation reactions in the fractions.
Asunto(s)
Cromatina/química , Hígado/química , Transcripción Genética/genética , Deficiencia de Vitamina E/genética , Animales , Antioxidantes/farmacología , Fraccionamiento Químico , Femenino , Membrana Dobles de Lípidos , Peroxidación de Lípido/efectos de los fármacos , Fluidez de la Membrana/efectos de los fármacos , Ratas , Ratas WistarRESUMEN
Intoxication of rats by 0,0-dimethyl-0-2,2-dichlorovinylphosphate (DDVPh) leads to marked biochemical changes of transcriptionally active (TACh) and repressed (RCh) liver chromatin fractions. These changes are connected with structural relaxation of the fractions, which is manifested by the increase of intensity of protein self-fluorescence. Free radical nature of these changes was supposed, which was proved by the modification of LPO reactions in the both chromatin fractions under the influence of the pesticide concerned.
Asunto(s)
Cromatina/efectos de los fármacos , Diclorvos/envenenamiento , Peroxidación de Lípido/efectos de los fármacos , Hígado/efectos de los fármacos , Animales , Cromatina/química , Cromatina/metabolismo , Femenino , Radicales Libres , Hígado/química , Hígado/metabolismo , Malondialdehído/metabolismo , Ratas , Ratas Wistar , Espectrometría de Fluorescencia , Transcripción Genética/efectos de los fármacosRESUMEN
The influence of the degree of liposomes oxidation on the parameters of their adsorption by montmorillonite was studied. It was shown that accumulation of the products of oxidation in liposomes, which occurred in the process of their incubation, feebly influenced the ability of liposomes to adsorb on the surface of the clay mineral. The increase of the degree of liposomes oxidation in this case lead to the lowering of the values of adsorption heats, however the kinetics of heat production was preserved.
Asunto(s)
Bentonita/química , Liposomas/metabolismo , Adsorción , Calor , Cinética , Oxidación-ReducciónRESUMEN
Lipid peroxidation (LPO), physico-chemical properties of the membranes and isoformic composition of microsomal cytochrome P-450 from the rat liver were studied under conditions of antioxidant insufficiency (AOI) which was modelled by exclusion of alpha-tocopherol from the animals' ration. An insignificant accumulation of microsomal diene conjugates and schiff bases against a sharp increase of the ability to the prooxidant stimulated LPO in vitro took place. A significant decrease of membrane lipid microviscosity and a change in surface properties of microsomal membranes of rats with AOI was determined. Absence of alpha-tocopherol in the ration was accompanied by a significant change in the content of separate isoforms of cytochrome P-450 exhibited in growth of a polypeptide with m. w. 54 kDa and the lowering of proteins with m. w. 48 and 50 kDa. Less intensive quenching of tryptophan fluorescence by acrylamide was also revealed, which testified to a lower accessibility of the quencher to membrane proteins or their fluorophore sites. Modification of lipid composition and of physicochemical properties of the rat liver membrane microsomes which was observed at AOI was significantly correlated by pretreatment with the antioxidant 4-methyl-2,6-ditretbutylphenol (ionol).
Asunto(s)
Antioxidantes , Hidroxitolueno Butilado/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Microsomas Hepáticos/enzimología , Deficiencia de Vitamina E/metabolismo , Animales , Femenino , Membranas Intracelulares/metabolismo , Peroxidación de Lípido , RatasRESUMEN
Interaction of phosphatidyl choline liposomes with erythrocytes during spontaneous lysis of the latter has been studied. It is shown that hemoglobin which is released during the lysis of erythrocytes is found by liposomes which in their turn are absorbed on the external erythrocyte surface. In this case the binding of hemoglobin by liposomes takes place with a greater speed than its release during erythrocyte lysis and is accompanied by a change in its conformation. Possibilities of the microcalorimetry methods for studying the interaction of liposomes with erythrocytes under the conditions mentioned above are considered.
Asunto(s)
Eritrocitos/metabolismo , Hemólisis/fisiología , Liposomas/metabolismo , Fosfatidilcolinas/metabolismo , Animales , Perros , Hemoglobinas/metabolismo , Hemólisis/efectos de los fármacos , Unión Proteica , Conformación Proteica/efectos de los fármacosRESUMEN
Physico-chemical parameters of membranes of skeletal muscles' sarcoplasmic reticulum in antioxidant insufficiency, which was modelled by excluding alpha-tocopherol from the animals ration, and after treatment with phenol antioxidant ionol were studied. It was shown that activation of lipid peroxidation in vitamin E insufficiency results in a significant lowering of microviscosity of lipid bilayer membranes of sarcoplasmic reticulum. Using polarography significant changes in membrane protein conformation were revealed, which were characterized by lowering of integrity and by disorganization of protein globules. Treatment of animals with antioxidant insufficiency with ionol led to certain normalization of changes of physico-chemical characteristics of the learned membrane structures caused by lipid peroxidation.
Asunto(s)
Antioxidantes , Músculos/efectos de los fármacos , Peróxidos/farmacología , Retículo Sarcoplasmático/efectos de los fármacos , Animales , Hidroxitolueno Butilado/farmacología , Membrana Celular/química , Membrana Celular/efectos de los fármacos , Femenino , Membrana Dobles de Lípidos , Peroxidación de Lípido , Músculos/metabolismo , Polarografía , Ratas , Ratas Endogámicas , Retículo Sarcoplasmático/metabolismo , Espectrofotometría UltravioletaRESUMEN
The fluorescence and polarography methods are used to establish certain differences in conformation characteristics of transcriptionally active and repressed forms of rat liver chromatin. The data obtained prove the nucleo-soma ability to aggregation in the repressed chromatin and confirm a decondensed character of packing in transcriptionally active chromatin. It is supposed that these peculiarities are connected with different content of calcium and iron ions in the studied fractions of chromatin. Lipids, being the components of chromatin fractions, are packed with proteins in a form of bilayer structure. The packing character is similar in the both chromatin fractions. But microviscosity of the lipid bilayer in transcriptionally active chromatin is significantly lower than that in the repressed one and this may be one of reasons of different transcriptional activity and ability to peroxidation of the studied chromatin forms.
Asunto(s)
Cromatina , Lípidos/química , Transcripción Genética , Animales , Cromatina/química , Femenino , Polarización de Fluorescencia , Peroxidación de Lípido , Conformación Molecular , ARN/biosíntesis , Ratas , Ratas EndogámicasRESUMEN
Chloroaklylamine derivatives are studied for their effect on the structural organization of mitochondrion and microsome membranes of the cattle liver. The antitumoural preparation--embiquin is shown to increase microviscosity of hydrophobic zones of a lipid matrix of mitochondrial membranes and to decrease the quantity of immobilized cytochrome C, whereas it has no effect on microsomal membranes. It is established that the replacement of a methyl substituent in the nitrogen atom of chloroalkylamines by the metaxylyl one evokes no qualitative differences in the character of disturbances of the structural properties of mitochondrial membranes, however it induces structural perturbations in the microsomal membranes.
Asunto(s)
Antineoplásicos/farmacología , Membranas Intracelulares/efectos de los fármacos , Mecloretamina/farmacología , Microsomas Hepáticos/efectos de los fármacos , Mitocondrias Hepáticas/efectos de los fármacos , Compuestos de Mostaza Nitrogenada/farmacología , Animales , Bovinos , Grupo Citocromo c/metabolismo , Técnicas In Vitro , Membranas Intracelulares/enzimología , Membranas Intracelulares/metabolismo , Lípidos de la Membrana/metabolismo , Proteínas de la Membrana/efectos de los fármacos , Proteínas de la Membrana/metabolismo , Microsomas Hepáticos/enzimología , Microsomas Hepáticos/metabolismo , Mitocondrias Hepáticas/enzimología , Mitocondrias Hepáticas/metabolismo , Albúmina Sérica/metabolismo , Espectrometría de Fluorescencia , ViscosidadRESUMEN
Physiochemical conformity of the alpha-tocopherol interaction with hepatic microsomal membranes has been studied by means of fluorescent probes (pyrene and 1-anilinonaphthalene-8-sulphonate). The microsomal membrane microviscosity is shown to sharply decrease under conditions of the antioxidant deficiency with vitamin E expelled into animals normalizes microviscosity, but feebly influences the microsomal surface charge. Microcalorimetry has been used to establish that penetration of tocopherol into microsomal membranes was accompanied by the exothermic effect.
Asunto(s)
Antioxidantes , Hidroxitolueno Butilado/farmacología , Membranas Intracelulares/efectos de los fármacos , Microsomas Hepáticos/efectos de los fármacos , Vitamina E/farmacología , Animales , Femenino , Colorantes Fluorescentes , Técnicas In Vitro , Membranas Intracelulares/metabolismo , Peroxidación de Lípido , Microsomas Hepáticos/metabolismo , RatasRESUMEN
Thermodynamic parameters of the bovine serum albumin interaction with phosphatidyl choline liposomes have been determined. It is shown that the bovine serum albumin is adsorbed on the liposomal surface without change of the globule conformation, the polar interactions making dominant contribution in immobilization. The complexing is characterized by a binding constant and a great number of binding sites.
Asunto(s)
Liposomas/metabolismo , Fosfatidilcolinas/metabolismo , Albúmina Sérica Bovina/metabolismo , Adsorción , Animales , Sitios de Unión , Bovinos , Conformación Proteica , TermodinámicaRESUMEN
The conformity of the ultrasonic treatment influence on characteristics of the forming liposomes from phosphatidylcholine water dispersion has been studied by means of spectrophotometry, atomic absorption spectrometry, thin layer and gel chromatography and electron microscopy. Optimal treatment conditions which allow attaining relatively homogeneous suspension of small unilamellar vesicles with the low peroxidation level and minimal lysophospholipid contents have been determined.
Asunto(s)
Liposomas/análisis , Sonicación , Ultrasonido , Cromatografía en Gel , Cromatografía en Capa Delgada , EspectrofotometríaRESUMEN
Adsorption of phosphatidylcholine liposomes by montmorillonite was studied for its effect on peroxidation of phospholipids and structure of the bilayer. The UV spectroscopy has shown that adsorption decreases peroxidation of lipids. A parameter is suggested for estimating an oxidation degree of lipids at the stage of the intensive formation of secondary products of their peroxidation. Fluorescent probes (1-anilinonaphthalene-8-sulphonate and pyrene) are used to establish that structural changes of the bilayer take place in adsorbed liposomes being followed by a decrease in the mobility of surface zones of phospholipid "heads" and by an increase in the polarity of hydrophobic parts of the bilayer.