[Antioxidant system activation in rats with experimental cirrhosis after injection of cryopreserved fetal liver cells].

The possibility to recover the antioxidant system in rats with experimental liver cirrhosis (LC) after allo- and xenotransplantation of cryopreserved fetal liver cells (FLC) was investigated. It was shown that the content of lipid peroxidation products in the blood serum of animals with LC four weeks after FLC transplantation decreased significantly as compared to control group. Such changes were accompanied by a significant increase of catalase (CAT), glutathione reductase (GR), Se-dependent glutathione peroxidase (GP) activity in the liver and total anti-oxidative activity (AOA) of blood. Obtained results demonstrate that the main direction of FLC effects in animals with LC agree with that we observed previously in other experimental models (partial hepatectomy, chronic alcohol poisoning and hypercholesterolemia). In conclusion, cell therapy may be considered as the universal method for correction of disorders in regulation of free-radical processes in various experimental pathologies.

[Activity of enzymatic antioxidant system in the rat tissues under conditions of over- and restricted nutrition].

The state of enzymatic antioxidant system and thyroid status in the rat tissues under early postnatal overnutrition leading to shortening of life-span and calorie-restricted diet extending lifespan have been studied. It was found that the concentration of thyroxine, body weight and content of lipid hydroperoxides in the blood serum and liver post-mitochondrial fraction of rats had been reliably increased. At the same time the concentration of GSH and GSSG, superoxide dismutase, Se-dependent glutathione peroxidase (GP) activities in the liver and GP activity in the blood serum of experimental rats were reduced. The use of calorie-restricted diet for 2 months showed considerable decrease of thyroxine and triiodothyronine concentration, body weight and the content of lipid hydroperoxides in the blood serum of experimental rats compared with control. At the same time GP activity in the liver, Se-dependent GP activity and content of ceruloplasmin in blood of experimental rats were essentially enhanced. The obtained results allow to conclude that from all studied indices the activity of GSH-dependent antioxidant system (especially Se-dependent GP activity) and thyroid status revealed the most sensible changes in response to the used kind of nutrition. Unlike hypocaloric diet overnutrition results in a decrease of Se-dependent GP activity in the liver and blood of rats. That may be the most crucial moment in the maintenance of prooxidant-antioxidant balance of tissues.

[The effect of three different hypocaloric diets on oxidative phosphorylation and activity of enzymatic antioxidant system in rat liver mitochondria].

Thyroid status, liver mitochondrial functional state and activity of enzymatic antioxidant system after 2-months maintenance of rats on three different hypocaloric diets were investigated. It was established that the level of calorie restriction was directly proportional to triiodothyronine content in blood and to decrease of phosphorylating oxidation intensity (with its efficacy preservation) and was inversely proportional to increase of Se-dependent glutathione peroxidase activity.

[The influence of gamma-irradiation and alimentry factors on prooxidant-antioxidant rat's liver and blood system].

The shift of prooxidant-antioxidant balance in side of prooxidants was revealed in rat liver mitochondria and in microsomes and in blood plasma in response to single irradiation (dose 8 Gy). The shift was more expressed in animals with nutrition unbalanced on animal proteins and antioxidant vitamins. In the main it was explained by the initially reduced activity of enzymatic antioxidant system and especially Se-dependent glutathione peroxidase activity. The apply of food addition from Aronia melanocarpa fruits had delayed lipid peroxidation activation in irradiated animals but practically had no effect on activity of enzymatic antioxidant system. The established essential decrease of Se-dependent glutathione peroxidase activity under unbalanced diet is considered the most crucial point in the maintenance of enzymatic antioxidant system reliability in irradiated animals.

[Activity of glutathione-dependent antioxidant system of the rat liver and blood depending on gamma-irradiation and diet].

The role of the glutathione-dependent antioxidant system in the prooxidant-antioxidant balance support was studied in the experiments with Wistar male rat under single gamma-irradiation (8 Gr dose), fed with unbalanced (as to animal proteins and antioxidant vitamins) diet and with addition of Aronia melanocarpa. Single gamma-irradiation of animals led to the decrease of selenium-dependent glutathione-peroxidase activity in the blood plasma and glutathione-S-transferase activity decrease in rat liver mitochondria. Animals which received the unbalanced food allowance under irradiation showed more expressed change of glutathione-dependent antioxidant enzymes activity, namely--proved decrease of glutathione-peroxidase and glutathione-S-transferase activity in liver microsomes and less expressed activation of selenium-dependent glutathione-peroxidase activity in the postmitochondrial fraction of laboratory animals liver. Introduction of the A. melanocarpa food supplement in the unbalanced diet of the laboratory animals which in vitro demonstrated expressed antioxidant and antiradical activity had no effect upon glutathione-peroxidase activity in the investigated tissues. Obtained data concerning significant decrease of the activity of glutathione-dependent antioxidant system and, particularly, of the selenium-dependent glutathione-peroxidase activity under the unbalanced diet condition may be useful in maintenance of prooxidant-antioxidant balance in the tissues of irradiated animals. Allowing for the above stated it is advisable to seek for new food additives which increase activity of the endogenous glutathione-dependent antioxidant enzymes for human tolerance improvement, especially under the unbalanced food allowance condition.

[Effect of biologically active substances of animal and plant origin on prooxidant-antioxidant balance in rats with experimental prostatic hyperplasia].

The effect of biologically active complexes of animal (prostatilen) and plant (permixon) origin on physiological indices of prostate and prooxidant-antioxidant balance in prostate and blood was studied in rats with the hyperprolactinemia-induced prostatic hyperplasia. It was shown that both prostatilen (1 mg of the total peptides per kg) and permixon (100 mg of Serenoa repens extract per kg) prevent increase in the prostate mass and volume, in the content of lipid hydroperoxides, and in the glutathione peroxidase activity in prostate. Prostatilen, in contrast to permixon, normalized the content of lipid hydroperoxides (increased under hyperplazia conditions) and increases glutathione peroxidase activity (reduced under hyperplazia conditions).

[Effect of subtherapeutic doses of docetaxel (taxotere) on the efficacy of radiotherapy and pro-oxidant-antioxidant balance in rats with Guerin's carcinoma]. / Vliianie subterapevticheskikh doz dotsetaksela (taksotera) na éffektivnost' radioterapii i prooksidantno-antioksidantnyi balans u krys s kartsinomoi Gerena.

In the experiments at Wistar male rats the effect of subtherapeutic doses of docetaxel (5 and 10 mg/kg) on the radiotherapy efficacy (20 Gy of single-dose X-rays) namely growth rate of Guerin's tumor and prooxidant-antioxidant balance in liver and blood of animals bearing tumors was investigated. It has been demonstrated that docetaxel at dose 5 mg/kg given 18 hours before irradiation resulted in significant tumor growth delay (2.3-2.7-fold) in comparison with group of rats that received only irradiation. After application of higher dose of docetaxel there was no statistically significant change of tumor size along the whole experiment (14 and 21 days after tumor implantation). Content of lipid peroxidation products was revealed to be considerably increased after chemotherapy and concurrent irradiation when docetaxel was used in a dose of 10 mg/kg. At the same time glutatione peroxidase activity and antioxidative activity of blood plasma were reduced. In the rat liver chemoradiotherapy led to decrease of glutathion peroxidase and glutathione-S-transferase activity to greater degree at docetaxel dose of 10 mg/kg. The obtained results allow to conclude that higher dose of docetaxel and concurrent irradiation resulted in the most effective Guerin's carcinoma growth delay and considerable deviation of antioxidant-prooxidant balance of tissues in the direction of the last.

[Lipid peroxidation and regulation of it in rat blood and liver under the experimental alimentary radionuclide effect]. / Peroksydne okyslennia lipidiv i ioho rehuliatsiia u krovi ta pechintsi shchuriv za umov eksperymental'noho alimentarnoho radionuklidnoho vplivu.

Effect of alimentary radionuclide load (137Cs, 700 Bq for animal per day during 7, 14 and 22 days) on the lipid peroxidation intensity and blood and liver enzymatic and non-enzymatic antioxidant system in the Wistar male-rats was investigated. It was found that considerable change of antioxidant system activity in plasma and erythrocytes of experimental animals was already noticeable on the 7th day of radionuclide load. After 22 days of experiment the reliability of glutathione-dependent antioxidant system in blood was essentially decreased and lipid hydroperoxide content was increased. The increase of lipid peroxidation intensity was also found in the experimental animals liver but at the same time the activities of all studied enzymes of antioxidant system were significantly higher than they were in the control rats.

[The effect of tetracycline and silibore on lipid peroxidation in the liver od rats of various age]. / Vliianie tetratsiklina i silibora na perekisnoe okislenie lipidov pecheni krys raznogo vozrasta.

As shown by accumulation of malonic dialdehyde and chemiluminescence rate monitoring tetracycline activated both NADPH- and ascorbate-dependent lipid peroxidation in liver tissue of 1, 3, 12 and 24 months old rats. The most distinct induction of lipid peroxidation was observed in old animals, which appears to occur due to a decrease in efficiency of NADPH-GSH-dependent enzymatic antioxidant system. Silibore prevented the stimulating effect of tetracycline on enzymatic and nonenzymatic lipid peroxidation, being apparently involved in hepatoprotective effect.

[Features of ischemic injuries to membranes and activation of lipid peroxidation in the myocardium of rats of various ages]. / Osobennosti ishemicheskogo povrazhdeniia membran i aktivatsiia perekisnogo okisleniia lipidov v miokarde krys raznogo vozrasta.

The model of interrupted ischemia of the isolated heart has been used to show that the yield of lactate dehydrogenase into perfusate in experiments on old rats is described by more sharply pronounced S-like dependence than that in young immature animals. The activation of lipid peroxidation precedes the sarcolemma damage and is relatively more manifested in rats of middle and old age. The respiratory control of mitochondria (in homogenates) decreases considerably already 20 min after ischemia, however mitochondria retain their ability to synthesize ATP 3 h later as well. The causal-effect relationship between the activation of lipid peroxidation and partial disturbance of the mitochondrial function remains unclear.

[Peroxidation of biomembrane lipids and its enzymatic regulation during aging in the rat]. / Perekisnoe okislenie lipidov biomembran i ego fermentativnaia reguliatsiia pri starenii krys.

Measurement of the intensity of chemiluminescence and accumulation of the peroxidation products detected in the reaction with thiobarbituric acid (TBA-active products) has shown that with the ageing of rats the intensity of peroxidation of biomembranes' lipids gets lower in the liver and heart homogenates and tends to decrease in the brain homogenates. A strict correlation is established to exist between the level of TBA-active products and the chemiluminescence intensity independent of the age, organ and the method of initiation of lipids' peroxidation and its intensity. Considerable age changes in the rate of lipids' peroxidation in the liver and heart homogenates may be associated with an increase in the activity of a number of such antioxidant enzymes as superoxide dismutase, glutathione peroxidase, glutathione transferase and catalase in the postnatal ontogenesis of rats.

[Lipid hydroperoxide levels in the heart and liver of rats of various ages]. / Soderzhanie gidroperekisei lipidov v serdtse i pecheni krys razlichnogo vozrasta.

The level of lipid hydroperoxides and secondary products of peroxide oxidation of lipids reacting with 2-thiobarbituric acid (TBA) has been studied in the heart and liver of Wistar male rats aged 1, 3, 12 and 24 months. It is shown that the both indices in the heart lower in the pubertal period of ontogenesis and do not vary with the further ageing. The content of hydroperoxides in the liver is unchanged and that of secondary TBA-active products decreases with the age.

[Enzymes utilizing hydroperoxides and O ./2 in the myocardium of rats of different ages]. / Fermenty utilizatsii gidroperoksidov i O ./2 v miokarde krys raznogo vozrasta.

Superoxide dismutase activity of myocardial cytosol increases with rat age (1, 3, 12, 24 months) whereas catalase activity is unchanged. Glutathione peroxidase activity with H2O2, cumene and t-butyl hydroperoxides as substrates increases more than 1.5-fold over the period from 1 to 12 months. The high activity of these enzymes is maintained in 24-month-old rats.

[Enzymes of the antioxidant system of rat liver during aging]. / Fermenty antioksidantnoi sistemy pecheni krys pri starenii.

It is shown that ageing induces in rats intensification of a GSH-dependent antioxidant effect of the liver cytozole, growth of glutathione-S-transferase activity of cytozole, microsomes and mitochondria, a decrease of the NADPH generation rate in cytozole with malate and glucose-6-phosphate oxidation (the rate remaining at high level with isocytrate oxidation). It is supposed that under definite physiological conditions a lowered rate of NADPH generation in the malate dehydrogenase and glucose-6-phosphate dehydrogenase reactions in old animals may limit the efficiency of the NADPH-GSH-dependent antioxidant system of the liver cells. The peroxidase activity of cytochrome P-450 of microsomes and the glutathione reductase activity (EC 1.6.4.2) of cytozole rise in the liver of rats up to their 12 months and fall considerably with ageing. Cytochrome P-450 in the membranes of endoplasmic reticulum plays the role of an antioxidant.