ABSTRACT
In this work the experimental metabolic syndrome on the basis of protamine sulfate modeling in guinea pigs was reproduced and pathological processes in the liver of experimental animals were studied. We determined the level of free radicals and markers of liver damage in the blood of experimental animals. We investigated the liver glycogen content and K+,Na+-ATPase activity in the liver of experimental animals as well as measured the cytochrome P450 2E1 (CY P2E1) expression one of the main factors of oxidative stress. Evidence of development of hepatotoxic processes, increasing of the CY P2E1 level as well as of the free radical level in the animals with metabolic syndrome were found. Using of CY P2E1 inhibitors had shown that the free radical level in the blood of experimental animals depended on the level of the enzyme expression and activity. The obtained results suggest that the changes in the CY P2E1 expression play an important role in the development of hepatotoxic processes upon experimental metabolic syndrome. It was assumed that pharmacological correction of the enzyme expression may be an important mechanism for the influence on the metabolic syndrome clinical course.
Subject(s)
Cytochrome P-450 CYP2E1 Inhibitors/pharmacology , Cytochrome P-450 CYP2E1/genetics , Liver/drug effects , Metabolic Syndrome/drug therapy , Animals , Cytochrome P-450 CYP2E1/metabolism , Disulfiram/pharmacology , Fomepizole , Free Radicals/antagonists & inhibitors , Free Radicals/metabolism , Gene Expression Regulation , Glycogen/metabolism , Guinea Pigs , Liver/enzymology , Liver/pathology , Male , Metabolic Syndrome/chemically induced , Metabolic Syndrome/enzymology , Metabolic Syndrome/pathology , Oxidative Stress/drug effects , Protamines , Pyrazoles/pharmacology , Quercetin/pharmacology , Sodium-Potassium-Exchanging ATPase/genetics , Sodium-Potassium-Exchanging ATPase/metabolismABSTRACT
The level of insulin production is one of the integral parameters during the modeling of metabolic syndrome in animals. Comparison of this parameter with blood glucose level can characterize the degree of insulin resistance of cells. In this work we determined the level of insulin in pancreatic cells of guinea pigs under normal conditions and during metabolic syndrome. The obtained results were compared with the blood glucose level of experimental animals. In this work we used the methods of histochemical and immunohistochemical analysis of insulin production. It was found that in guinea pigs metabolic syndrome modeling is accompanied by impaired insulin synthesis, degenerative changes in pancreatic tissue and increased blood glucose level. The data obtained suggest that the experimental animals have insulin resistance, which is the main pathogenetic mechanism in the development of metabolic syndrome.
Subject(s)
Blood Glucose/metabolism , Insulin Resistance , Insulin/blood , Metabolic Syndrome/blood , Metabolic Syndrome/pathology , Pancreas/pathology , Animals , Guinea Pigs , Humans , Immunohistochemistry , Male , Metabolic Syndrome/chemically induced , Microtomy , Pancreas/metabolism , Paraffin Embedding , ProtaminesABSTRACT
In this work we investigated changes in the cytochrome P450 2E1 (CYP2E1) expression level in the liver of mice that have been exposed to psycho-emotional stress (PES). It was shown twofold relative to control reduction of the enzyme, which does not normalize after termination of the stressor. The changes in level of Cyp2e1 mRNA is not observed at any time point of the experiment. At the same time it was found a significant decrease in the expression level of hsp90--one of the factors determines of the level of CYP2E1 degradation in the cell. Also it was shown, the oxidative stress develops in the liver of experimental animals, and this is indicated by a 3-fold increase in the malondialdehyde level on the background of a 5-fold decrease in catalase activity. A decrease in the level of expression of cytochrome P450 2E1 in the liver of mice that have been exposed to psycho-emotional stress is due to the intensification of the peroxide process and the development of oxidative stress. Reduction of protein content of CYP2E1 is apparently not related to the hsp90-dependent processes of its degradation in the cell.
Subject(s)
Cytochrome P-450 CYP2E1/metabolism , HSP90 Heat-Shock Proteins/metabolism , Liver/metabolism , RNA, Messenger/metabolism , Stress, Psychological/metabolism , Animals , Catalase/metabolism , Chronic Disease , Cytochrome P-450 CYP2E1/genetics , Gene Expression , HSP90 Heat-Shock Proteins/genetics , Male , Malondialdehyde/metabolism , Mice , Mice, Inbred C57BL , Oxidative Stress , RNA, Messenger/genetics , Stress, Psychological/genetics , Stress, Psychological/physiopathologyABSTRACT
Diabetes mellitus is one of the three most common modem diseases. A number of animal models is used in investigations of the mechanisms of development of the disease. Most of these models replicate the symptoms of type 1 diabetes mellitus. The development of type 2 diabetes is caused by the insulin resistance, hyperglycemia, structural and functional disorders of the pancreatic cells. Investigation of pathogenesis of type 2 diabetes is complicated by the lack of adequate models of this disease. In this work, based on existing hyperglycemia model, we propose the model of metabolic syndrome as a precursor of type 2 diabetes. The development of metabolic syndrome symptoms was caused by 28 days long intramuscular injection of protamine sulfate to guinea pigs at a dose of 15 mg/kg along with keeping of animals on a high glucose diet. Increased blood glucose and cholesterol levels, reduction of glycogen in liver, the structural and functional damage and reduce in the number of functionally active beta-cells in the pancreas of the experimental animals were observed. The results confirm the development of the metabolic syndrome symptoms in experimental animals, which makes it possible to use such methodical approach in creation of promising type 2 diabetes model.
Subject(s)
Diabetes Mellitus, Type 2/pathology , Disease Models, Animal , Glucose/administration & dosage , Hyperglycemia/pathology , Insulin-Secreting Cells/pathology , Metabolic Syndrome/pathology , Animals , Diabetes Mellitus, Type 2/chemically induced , Diabetes Mellitus, Type 2/metabolism , Diet , Glucose/metabolism , Glycogen/metabolism , Guinea Pigs , Hyperglycemia/chemically induced , Hyperglycemia/metabolism , Injections, Intramuscular , Insulin Resistance , Insulin-Secreting Cells/metabolism , Liver/metabolism , Male , Metabolic Syndrome/chemically induced , Metabolic Syndrome/metabolism , ProtaminesABSTRACT
A comparison has been made between spatial structures of human CYP2E1 obtained experimentally and those calculated using the computer methods. The structures were characterized by such parameters as total energy, protein pocket volume and total volume of molecules as well as the analysis of spatial geometry. The obtained results have proved that the model calculated and optimized by us can be used for studing the mechanisms of interaction of the active center of the enzyme with substrates and inhibitors. An assumption was made in the course of the research that one of the possible mechanisms of inactivation of the enzyme is the reduction of protein pocket volume, which prevents substrate access to the active center.
Subject(s)
Computer Simulation , Cytochrome P-450 Enzyme System/chemistry , Models, Chemical , Models, Molecular , Cytochrome P-450 Enzyme Inhibitors , Cytochrome P450 Family 2 , Enzyme Inhibitors/chemistry , Humans , Ligands , Protein Binding , Protein Conformation , Substrate SpecificityABSTRACT
The effect of continuous single and combined influence of exogenous stress factors (ethanol and low intensity gamma-radiation) on cytochrome P450 2E1 (1.14.14.1) expression in mice liver was studied. The chronic ethanol intake induced Cyp2E1 protein expression but not increased Cyp2e1 mRNA level. The first week of continuous combined influence of ethanol and gamma-irradiation was characterized by the increase of Cyp2E1 protein level, that was back to normal on second week. A small decrease of this index was observed at the end of the fifth week. The changes of Cyp2E1 protein amount accompanied the decrease of Cyp2e1 mRNA level.
Subject(s)
Cytochrome P-450 CYP2E1/biosynthesis , Ethanol/toxicity , Gamma Rays/adverse effects , Liver/enzymology , Adaptation, Physiological/drug effects , Adaptation, Physiological/radiation effects , Animals , Cytochrome P-450 CYP2E1/genetics , Free Radicals/metabolism , Gene Expression/drug effects , Gene Expression/radiation effects , Liver/drug effects , Liver/radiation effects , Male , Mice , Mice, Inbred BALB C , Oxidative Stress/drug effects , Oxidative Stress/radiation effects , Time FactorsABSTRACT
The effect of continuous low-intensity and acute high-intensity ionizing radiation in low and high doses on expression of cytochrome P450 2El (1.14.14.1) in mice liver was studied. It was shown, that changes of Cyp2e1 amount depended on the dose and intensity of ionizing radiation. Low doses of continuous gamma-radiation caused reliable decrease of Cyp2e1 expression on protein mRNA levels. Low doses of acute gamma-radiation lead to an increase of Cyp2el amount, while high doses--to a corresponding decrease. We showed, that low and high doses of acute gamma-radiation caused a significant decrease of Cyp2e1 mRNA level. We suppose that the detected changes of Cyp2el expression are associated with peroxidation process and development of oxidative stress.
