Tag Archives: glutathione peroxidase

Time-dependent effect of severe hypoxia/reoxygenation on oxidative stress level, antioxidant capacity and p53 accumulation in mitochondria of rat heart

O. A. Gonchar, I. N. Mankovska

Bogomoletz Institute of Physiology, National Academy of Sciences of Ukraine, Kyiv;
e-mail: olga.gonchar@i.ua

The intensity of oxidative stress, protein expression of antiapoptotic Bcl-2 as well as antioxidant enzymes manganese superoxide dismutase (MnSOD) and glutathione peroxidase (GPx) and their regulator p53 were studied in the mitochondria of rat heart. Sessions of repeated hypoxia/reoxygenation ((H/R), 5 cycles of 10 min hypoxia (5.5% O2 in N2) alternated with 10 min normoxia, daily) were performed in our study. It was shown that short-term sessions of H/R (during 1-3 days) caused a significant increase in the oxidative stress markers (ROS formation and lipid peroxidation), mitochondrial p53 translocation, a decrease in MnSOD­ protein expression/activity and Bcl-2 protein content, but up-regulated GPx. We have demonstrated that prolonged H/R (7-14 days) induced myocardial tolerance to fluctuation in oxygen levels that was associa­ted with the reduction in mitochondrial p53 protein content, elevation of mitochondrial Bcl-2 protein level, and increase in antioxidant capacity. A close correlation between the mitochondrial p53 accumulation and ROS formation as well as the activity and protein content of MnSOD and GPx allowed us to assume that p53 took an active part in the regulation of prooxidant/antioxidant balance in mitochondria of rat heart during repeated H/R.

Intensity of peroxidation processes and activity of antioxidant enzymes in rat tissues at high chromium level in the diet

R. Ya. Iskra, V. G. Yanovych

Institute of Animal Biology, National Academy of Agrarian Sciences, Lviv, Ukraine;
e-mail: ruslana_iskra@inenbiol.com.ua

The data on the influence of chromium in different tissues of rats at its consumption with mixed fodder in the form of CrCl3×6H2O on the intensity of peroxidation processes and activity of antioxidant enzymes are presented. The degree of high chromium content in the studied tissues of rats at its addition to mixed fodder in the amount of 200 µg/kg during 30 days was established. Chromium content in the rat tissues decreased in the order: the spleen, heart, kidneys, lungs, brain, liver, skeletal muscle. In all tissues of rats fed with mixed fodder with chromium addition, except for skeletal muscles, content of lipid peroxidation products – hydroperoxide and TBARS-products decreased. The content of lipid peroxidation products decreased in the spleen, kidneys, liver and lungs. Also in all organs and tissues of rats the activity of glutathione peroxidase, glutathione reductase and catalase increased at the action of chromium. In the brain and kidneys the level of reduced glutathione increased. Superoxide dismutase activity was significantly higher not only in the heart and skeletal muscles of animals and is probably equal in the lungs and liver, and in other organs – the brain, kidneys and spleen in animals of the studied group the enzyme activity was lower as compared to animals of the control group. Obtained results demonstrate the regulatory influence of chromium on free radical process in the rat tissues.

Activity of the glutathione system of antioxidant defense in rats under the action of L-glutamic acid

N. O. Salyha

Institute of Animal Biology, National Academy of Agrarian Sciences of Ukraine, Lviv, Ukraine;
e-mail: ynosyt@yahoo.com

The data on the effects of glutamic acid (L-Glu), which is one of three amino acid – precursors of glutathione on animals organism is quite controversial because research in this area remain relevant. The aim of our research was to find out what impact the additional  introduction of L-Glu on the activity glutathione system of antioxidant defence and the content of lipid peroxidation products­ in various organs and tissues of rats. The effect of additional (285 and 715 mg/kg, respectively) introduction to the diet of L-Glu on the activity of antioxidant enzymes and intensity of peroxidation processes in various tissues of rats was studied. It is shown that in the liver, spleen and kidneys of rats which received additional 715 mg/kg of L-Glu content of reduced glutathione and glutathione peroxidase activity increased. A decrease of the content of lipid hydroper­oxides and TBA-active products in tissues of animals which received additional 285 and 715 mg/kg of L-Glu into the diet was found. We have also found that the enrichment of rat’s diet by L-Glu during 30 days resulted in a change of glutathione part of antioxidant system and intensity of lipid peroxidation. More intensive changes in these indices were observed in animals which received additional 715 mg/kg of L-Glu into the diet.

Changes in glutathione system and lipid peroxidation in rat blood during the first hour after chlorpyrifos exposure

V. P. Rosalovsky, S. V. Grabovska, Yu. T. Salyha

Institute of Animal Biology, National Academy of Agrarian Sciences of Ukraine, Lviv;
e-mail: ros.volodymyr@gmail.com

Chlorpyrifos (CPF) is a highly toxic organophosphate compound, widely used as an active substance of many insecticides. Along with the anticholinesterase action, CPF may affect other biochemical mechanisms, particularly through disrupting pro- and antioxidant balance and inducing free-radical oxidative stress. Origins and occurrence of these phenomena are still not fully understood. The aim of our work was to investigate the effects of chlorpyrifos on key parameters of glutathione system and on lipid peroxidation in rat blood in the time dynamics during one hour after exposure. We found that a single exposure to 50 mg/kg chlorpyrifos caused a linear decrease in butyryl cholinesterase activity, increased activity of glutathione peroxidase and glutathione reductase, alterations in the levels of glutathione, TBA-active products and lipid hydroperoxides during 1 hour after poisoning. The most significant changes in studied parameters were detected at the 15-30th minutes after chlorpyrifos exposure.

Antioxidant defense system state in blood plasma and heart muscle of rats under the influence of histamine and sodium hypoclorite

O. I. Bishko, N. P. Harasym, D. I. Sanahurs’kyj

Ivan Franko National University of Lviv, Ukraine;
e-mail: oliabishko@gmail.com

There is a wide spectrum of antihistamine drugs in the pharmaceutical market, however all these chemical preparations cause side effects. Therefore, new alternative ways for histamine detoxication are to be found. For this aim in our experiment sodium hypochlorite was used because its solution possesses strong oxidizing properties. The influence of histamine and sodium hypochlorite on the antioxidant defence system state of blood plasma and cardiac muscle in rats has been researched. It was shown, that the investigated factors result in the disruption of the antioxidant system. It was found that histamine injection in concentration of 1 and 8 μg/kg in plasma leads to the increase of superoxi­de dismutase activity during all the experiment. When studying enzymes, that catalyze hydroperoxides and Н2О2 decomposition it was shown that under the influence of histamine in a dose 1 μg/kg, the glutathione peroxidase activity increased on the 1st day of the experiment. However, on the 7th day of the experiment the increase of both glutathione peroxidase and catalase activity was fixed. The deviation in superoxide dismutase function in rats plasma under the action of sodium hypochlorite has been established. The activity of enzymes that decompose Н2О2 and hydroperoxides were inhibi­ted. Under the influence of histamine in the heart tissues we have stated the disturbance of superoxide dismutase work and increase of catalase activity and decrease of glutathione peroxidase activity. The influence of sodium hypochlorite on the myocardium of intact animals as well as joint influence of sodium hypochlorite and histamine result in the increase of superoxide dismutase and catalase activity and lead to the conside­rable decline of activity of glutathione peroxidase.

The activity of prooxidant-antioxidant system in loach embryos under the action of microwave radiation

M. M. Yaremchuk, M. V. Dyka, D. I. Sanagursky

Ivan Franko National University of Lviv,Ukraine;
e-mail: m.yaremchuk@i.ua

Electromagnetic radiation (EMR) affects biological organisms, primarily on the cellular level. However, the effects of EMR at low-intensity exposure on animals and state of metabolic systems are not fully defined yet. Thus, research of microwave radiation influence on the processes of lipid peroxidation and antioxidant protection system is important for understanding the mechanisms of EMR action on the cell, in particular, and organism development on the whole. The content of lipid peroxidation products – lipid hydroperoxides, thiobarbituric acid reactive substances and the activity of antioxidant enzymes – superoxide dismutase, glutathione peroxidase and catalase in loach embryos under the action of microwave radiation (GSM-900 MHz, SAR = 1.1 Vt/kg) lasting 1; 5; 10 and 20 min during early embryogenesis were studied. It has been found that content of lipid peroxidation products in germ cells undergoes significant changes under the action of low-intensity EMR. The effect of microwave radiation (1, 5, 10 min) leads to the increase of superoxide dismutase activity, nevertheless, 20 min exposure decreased this index to the level of control values as it is shown. It has been established that EMR at frequencies used for mobile communications reduce the activity of antioxidant protection system components, especially catalase and glutathione peroxidase. The growth of catalase activity at the 10-cell stage of blastomere division (P < 0.05) is an exception. The results of two-way analysis of variance attest that microwave radiation factor causes the large part of all observable modifications.

State of antioxidant system of rat thymocytes in experimental ulcerogenesis

V. A. Kovaleva, L. M. Gaida, A. E. Shevchenko, D. V. Shelest, L. I. Ostapchenko

Educational and Scientific Centre Institute of Biology,
Taras Shevchenko Kyiv National University, Ukraine;
e-mail: vikikov@univ.kiev.ua

Features of free radical processes and their impact on the implementation of immunocompetent cells of their functions under conditions of peptic ulcer are insufficiently studied today. Reduced activity of catalase 1.7 and 3.4 times and that of glutathione peroxidise  ~ 2.0 times, accordingly, were observed in both models of gastric ulceration (stress ulcer and ethanol one). Enzymatic activity of superoxide dismutase decreased 1.5 times and activity of glutathione transferase increased 1.8 times in the stress model in contrast to the ethanol model of stomach ulcer. Obtained results indicate the exhaustion of antioxidant system in rats’ thymocytes under experimental ulcerogenesis. These data confirm complex negative effect of ulcer on the organism.