Effects of sex hormones on plasma lipid peroxidationin vitro

The effects of sex steroid hormones on the level of plasma lipid peroxidation are studiedin vitro. Estradiol shows pronounced antioxidative activity; progesterone and testosterone slightly suppress lipid peroxidation only when used in high concentrations. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 7, pp. 73–76, July, 1997     

Effects of sex steroid hormones on lipid peroxidation and glutathione antioxidant system in rat skin

Effects of estradiol and testosterone on the intensity of lipid peroxidation and contents of glutathione redox system components in the dermis and epidermis of rat skin were studied. Only estradiol induced considerable dose-dependent and tissue-specific biphasic antioxidant effects on the skin. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 128, No. 12, pp. 663–666, December, 1999     

Comparison of lipid peroxidation parameters in the heart,liver, and brain of rats with different degrees of resistance to hypoxia

The relationship between the intensity of lipid peroxidation and the activity of the antioxidant system in the heart, liver, and brain is studied in male Wistar rats with low and high resistance to hypoxia tested by being “raised” to an altitude of 11.5 km and in intact outbred rats. It is found that in all groups of rats the content of lipid peroxidation products is highest in the liver, lower in the heart, and lowest in the brain. In all groups, the rate of the ascorbate-induced lipid peroxidation is highest in the brain, lower in the liver, and lowest in the heart. The activity of the antioxidant system is highest in the brain, lower in the liver, and lowest in the heart of low-resistance and outbred rats, while in high-resistance rats it is the same in all the organs. Thus, the difference in the parameters of lipid peroxidation and, particularly, of the antioxidant system in the studied organs is most pronounced in rats with a low resistance to hypoxia. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 2, pp. 138–143, February, 1996 Presented by A. I. Archakov, Member of the Russian Academy of Medical Sciences     

Effect of the tranquilizer mebicar on lipid metabolism and lipid peroxidation on the model of hypokinesia in rats

Daily 18-hour hypokinesia induces atherogenic shifts in the blood lipid spectrum and activates lipid peroxidation in rats. Mebicar is shown to have a correcting effect on lipid metabolism and on the intensity of lipid peroxidation. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, No. 5, pp. 535–537, May, 1996     

Ca-dependent ATPase activity and lipid peroxidation in the microsome fraction of renal medulla after thermal ischemia with and without α-tocopherol protection

Thermal ischemia of rat kidneys for 30 min induces lipid peroxidation with simultaneous activation of Ca-dependent ATPase in microsomes. In the presence of the channel-forming antibiotic alamethicin this activity decreases, indicating an increased passive permeability of the membrane vesicles for Ca²⁺ and ATP with a decrease in the true activity of the enzyme after ischemia. α-Tocopherol reduces the intensity of lipid peroxidation in the microsome fraction isolated from kidneys after thermal ischemia and protects ATPase activity in the presence and absence of alamethicin in the incubation medium. It is suggested that peroxidation of membrane phospholipids activated by thermal ischemia is one of the causes of decreased true activity of Ca-dependent ATPase and increased passive permeability of the kidney membranes for Ca²⁺ and ATP. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 9, pp. 289–291, September, 1997     

Intensity of lipid peroxidation: Indicator of inflammation severity in chronic bronchitis

The content of products of lipid peroxidation and antioxidative activity were measured in exhaled air condensate and blood sera of patients with chronic bronchitis. Exacerbation of purulent bronchitis was found to be associated with an increase of heptane-soluble products of lipid peroxidation in serum and condensate, which was not observed in patients with catarrhal bronchitis. In catarrhal bronchitis, the content of heptane-soluble products is increased only in the serum; antioxidative activity increased in exhaled air condensate in catarrhal bronchitis and decreased in serum and condensate in purulent bronchitis. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 8, pp. 202–204, August, 1997     

Participation of cholesterol in hypochlorite-induced oxidation of cholesterol-phosphatidylcholine liposomes

The effect of cholesterol on hypochlorite-induced lipid peroxidation is studied in cholesterol-phosphatidylcholine liposomes. Cholesterol is shown to promote the accumulation of lipid peroxidation products in the presence of 0.1–3 mM hypochlorite anion in the incubation medium. The content of 2-thiobarbituric acid-reactive products is maximal at a cholesterol: phosphatidylcholine molar ratio of 1∶1. On the other hand, in the presence of low hypochlorite concentrations (10–100 μM) cholesterol is found to inhibit lipid peroxidation. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, No. 5, pp. 516–519, May, 1996     

Effect of ozone on lipid peroxidation in rat hearts isolated against the background of clinical death

Clinical death of outbred albino rats ensues after rapid blood loss due to a cut in the coronary coronary artery. Five minutes later, the isolated heart is perfused with ozonized Krebs-Henseleit solution. The activity of the antioxidant system in the heart is increased compared with that during routine oxygenation. The intensity of lipid peroxidation assessed by the intensity of chemiluminescence and the amount of lipid peroxidation products is significantly decreased during ozonization. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, № 2, pp. 161–163, February, 1996 Presented by B. A. Korolev, Member of the Russian Academy of Medical sciences     

Time course of lipid peroxidation during adaptation of men to novel ecological conditions

Changes in the intensity of lipid peroxidation and serum activities of superoxide dismutase and catalase were similar after 18-month adaptation to new ecological conditions of soldiers serving in two different regions. All values increased and reached the maximum by the 6th month, after which they stabilized; catalase activity decreased after 6 months. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 12, pp. 678–682, December, 1997     

Adaptation to periodic hypoxia and a diet supplemented with polyunsaturated class ω-3 fatty acids enhance the resistance of Ca2+ transport in the myocardial sarcoplasmic reticulum to free-radical oxidation

The relationship between the level of accumulation of lipid peroxidation products and the status of the Ca²⁺-transporting system in the sarcoplasmic reticulum of the rat myocardium is studied against the background of two cardioprotective factors, namely adaptation to periodic hypoxia and a diet enriched in polyunsaturated fatty acids of the ω-3 class. It is shown that the diet leads to an increase of level of lipid peroxidation products by 1.8 times in the heart and by 19 times in the liver, whereas a adaptation has no effect on the level of lipid peroxidation products in either of these organs. At the same time, the combined action of both factors considerably enhances the resistance of the myocardial Ca²⁺-transporting system to free radical-induced oxidation. Inin vitro experiments it is shown that adaptation to periodic hypoxia results in a more than twofold deceleration of Ca²⁺ transport inhibition during the oxidation induction by the Fe²⁺/ascorbate system; the diet causes a 3.5-fold deceleration of such inhibition. The results show that the accumulation of a high level of lipid peroxidation products is not always followed by damage to the Ca²⁺-transporting system in the myocardial sarcoplasmic reticulum. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 7, pp. 42–45, July, 1995 Presented by G. N. Kryzhanovskii, Member of the Russian Academy of Medical Sciences     

Lipid peroxidation parameters in the internal organs of rats with different degrees of resistance to hypoxia

Lipid peroxidation and the antioxidant system of the heart, liver, and brain are studied in adult male Wistar rats with high and low resistance to hypoxia tested by “raising” to an altitude of 11.5 km and in intact outbred rats. These parameters are found to be the same in the brain of low- and high-resistance rats, while the brain content of lipid peroxidation products is higher in both groups of Wistar rats compared with outbred rats. The heart and liver parameters are coupled to the resistance to hypoxia. Antioxidant activity prevails over lipid peroxidation in the hearts and livers of high-resistance rats, confirming that oxidation plays a major role in the damaging and lethal effects of acute hypoxia. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 1, pp 26–29, January, 1996 Presented by A. I. Archakov, Member of the Russian Academy of Medical Sciences     

Phospholipase A2 activity and lipid peroxidation during endotoxemia under conditions of experimental peritonitis

The severity of endotoxemia in peritonitis depends on morphofunctional state of the intestine determined by the intensity of free-radical lipid peroxidation and phospholipase A₂ activity, which are the highest on day 1 postoperation. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 129, No. 1, pp. 31–33, January, 2000     

Effect of melatonin on antioxidant activity and free radical lipid oxidation in traumatic shock

Effect of melatonin on antioxidant activity and lipid peroxidation in blood, heart, liver, and brain was studied in rats exposed to traumatic shock. Melatonin exerted a potent modulatory effect on antioxidant enzyme activity. Its efficacy depended on organ sensitivity to oxygen deficiency under conditions of traumatic shock. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 127, No. 4, pp. 387–391, April, 1999.     

Effect of endothelin-1 on DNA synthesis in tracheal epithelium and smooth muscle cells in newborn albino rats

Repeated (5-fold) intraperitoneal injections of 5×10⁻⁹ mol/kg endothelin-1 inhibited DNA synthesis in tracheal epitheliocytes and activated lipid peroxidation in the lungs of newborn rats. Endothelin-1 in a dose of 5×10⁻⁸ mol/kg stimulated proliferative activity of tracheal smooth muscle cells and intensified lipid peroxidation in the blood, which aggravated observed changes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 129, No. 3, pp. 294–296, March. 2000     

Effects of methyluracil and hydroxymethacil on free-radical oxidation in model systems

Three pyrimidine derivatives — methyluracil, hydroxymethacil (a new compound), and its lithium salt — were tested in model systems of differing complexity for antioxidant properties in comparison with the well-known antioxidant ionol. Tests for antiradical activity and for effects on spontaneous and Fe²⁺-ascorbate- or NADPH-dependent lipid peroxidation revealed high antioxidant activity (comparable to that of ionol) of the hydroxymethacil lithium salt. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 8, pp. 142–144, August, 1995 Presented by G.N. Kryzhanovskii, Member of the Russian Academy of Medical Sciences     

Multiresistance and lipid peroxidation system of thermoresistantShigella sonnei strains

The content of lipid peroxidation products increases in lipids isolated fromShigella sonnei after heating. Thermoresistant strains are characterized by higher activity of superoxide dismutase and catalase and by stable activity of glutathione reductase and glutathione transferase compared with thermolabile strains. Thermoresistant strains are also resistant to some antibiotics and hydrogen peroxide. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 122, No. 7, pp. 69–71, July, 1996     

Correlation between the parameters of free-radical lipid peroxidation and antioxidant system in children living in the north

A comparative study of the parameters of free-radical lipid peroxidation and antioxidant system was performed in children living in the North for various time periods. Intense lipid peroxidation was shown to be the key factor in the pathogeneses of several diseases caused by disturbances in the cellular membrane. Decreased resistance of red blood cells to peroxidative hemolysis is a phenomenon characterizing the adaptation-violating processes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 9, pp. 342–344, September, 1998     

Changes in the serum antioxidant system and lipid peroxidation under the influence of asbestos

The iron content, the state of the serum antioxidant system, and their relationship with the changes in lipid peroxidation in rat liver and lungs at the early stages of chrysotile-asbestos action, and the effect of the naturally occurring flavonoid rutin are studied. Intensification of lipid peroxidation in the liver and lungs and an increase in the oxyproline content, which correlates with the rise in serum antioxidant activity, are observed four weeks after a single intratracheal administration of 50 mg asbestos. The total serum iron content remains unchanged. Rutin has a pronounced anti-asbestos effect, inhibits the early stages of fibrosis, and facilitates normalization of the antioxidant system imbalance induced by asbestos. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 8 pp. 145–147, August, 1994     

Free-radical oxidation during experimental pneumonia

Lipid peroxidation in the lungs and plasma of albino rats was studied under normal conditions and during experimental pneumonia. In intact rats the content of lipid peroxidation products and the rate of their accumulation in lung homogenate is lower than in homogenates of other organs. Bivalent iron ions added to blood plasma did not induce chemiluminescence characteristic of lipid peroxidation. Experimental pneumonia intensifies production of active oxygen forms by alveolar macrophages and blood neutrophils and increases the content of lipid peroxidation products in lung homogenate. Combined application of antibiotics and antioxidant (vitamin E) during experimental pneumonia promotes normalization of free-radical oxidation and diminishes morphological alterations in the lungs. Translated fromByulleten' Eksperimental'noi Biologii i Medistiny, Vol. 129, No. 3, pp. 260–264, March, 2000     

Phosphoinositide response and alterations in free-radical oxidation in rats with catecholamine-induced cardionecrosis

Vascular spasm, hypertrophy of cardiac muscle cells, and necrotic changes in the myocardial tissue of rats administered norepinephrine in incremental doses over 14 days were accompanied by a considerable activation of lipid peroxidation and a weakening of antioxidant defense during the first 7 days of exposure to this injurious agent. On day 14, despite the greatly increased load of norepinephrine, the concentrations of lipid peroxidation products and the activity of antioxidant enzymes deviated from their control values to a lesser extent than on day 7. A similar change was shown by the concentration of brain tissue phosphatidylinositol-4,5-diphosphate, a source of second messengers, suggesting that the phosphoinositide system of second messengers is involved in the mechanisms whereby the destructive effects of norepinephrine are mitigated. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 8, pp. 137–139, August, 1995 Presented by I. P. Ashmarin, Member of the Russian Academy of Medical Sciences