Corticosterone and lipid peroxidation in rats after two exposures to cold

The relationships between serum corticosterone content, intensity of lipid peroxidation (LPO) and the concentration of tocopherol in tissues, and the transmembrane potential in thymocytes were studied in rats exposed to two consecutive coolings. Both exposures increased serum corticosterone. The first exposure activated LPO in the serum, while the second stimulated LPO in thymocytes. The second cooling lowered body temperature to a lesser extent than the first one. Body temperature did not depend on the content of LPO products or corticosterone, but negatively correlated with the content of tocopherol in the brain hemispheres and adrenal glands. The rats exhibiting high-level thermoregulation after the first exposure to cold showed a higher thymocyte transmembrane potential after the second cooling. The second exposure potentiated the negative relationship between the brain and serum content of corticosterone and LPO products, which indicates that the content of LPO products cannot be used as an index of stress intensity. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 127, No. 3, pp. 261–264, March, 1999     

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     

Phospholipid spectrum and lipid peroxidation in cell membranes of brain tissue in thymectomized rats

Lipid peroxidation (LPO) processes and the phospholipid (PL) content and composition in the homogenate and in the mitochondrial and supramitochondrial compartments of brain cells of adult male rats were studied 3 and 6 months after thymectomy. Thymectomy was found to markedly increase the rate of LPO and to reduce antiradical activity in all cellular compartments. A reliable increase of the level of total phospholipids in the homogenate and mitochondria was observed by the third month after thymectomy and a reduction of its control levels during the sixth month postoperation. On the other hand, a reduction of the content of total phospholipids was observed in the supramitochondrial fraction by the sixth month of the experiment. An increase of the phosphatidylethanolamine (PE) and phosphatidylserine (PS) contents was found to be mainly responsible for the changes in the level of total phospholipids. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 7, pp. 22–24, July, 1994 Presented by E. D. Gol'dberg, 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     

Effects of ubiquinone-10 on energy metabolism and lipid peroxidation in rats with myocardial ischemia

Preventive and therapeutic intraventricular administration of ubiquinone-10 to male rats with epinephrine-induced myocarditis increased the rate of oxidative phosphorylation, elevated the content of ATP, and inhibited lipid peroxidation in ischemic myocardium. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 130, No. 7, pp. 35–38, July, 2000     

Effects of ubiquinone-10 on energy metabolism and lipid peroxidation in rats with myocardial ischemia

Preventive and therapeutic intraventricular administration of ubiquinone-10 to male rats with epinephrine-induced myocarditis increased the rate of oxidative phosphorylation, elevated the content of ATP, and inhibited lipid peroxidation in ischemic myocardium. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 130, No. 7, pp. 35–38, July, 2000     

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 naftidrofuryl on lipid peroxidation in serum and erythrocyte plasma membrane of patients with diabetes mellitus

Effect of naftidrofuryl, a blocker of serotonin 5S₂-receptors (Dusodril-retard), on the malonic dialdehyde content in the serum and erythrocyte membranes is studied in diabetics with and without angiopathies. A 40-day treatment with Dusodril-retard normalizes the serum content of malonic dialdehyde, an intermediate product of lipid peroxidation, and has no effect on the malonic dialdehyde content of the erythrocyte plasma membrane. A negative correlation is established between blood levels of total cholesterol, β lipoproteins, and malonic dialdehyde levels in patients with diabetes mellitus. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 122, No. 9, pp. 338–341, September, 1996     

Beta-carotene-containing preparation carinat inhibits lipid peroxidation and development of renal tumors in rats treated with chemical carcinogen

The effects of pretreatment with β-carotene-containing preparation carinat on the development of renal tumors in rats receiving single intravenous injection of chemical carcinogen 3-(1-α-L-arabinopyranosyl)-1-methyl-1-nitrosourea were studied. Fourteen months after carcinogen administration, the degree of lipid oxidation in rat kidneys 2.5-fold surpassed that in animals receiving carinat in a dose producingin vivo antioxidant effect. Carinat decreased the total number of induced tumors and the incidence of mesenchymal renal tumors and suppressed the development of multiple tumors. The accumulation of lipoperoxides in the kidneys during carcinogenesis is associated with activation of free radical processes and carcinogen-induced inhibition of lipoperoxide enzymatic degradation and probably promotes renal malignancies due to co-carcinogenic action of these compounds. The data suggest that carinat-induced suppression of tumor development attests to antioxidant effects of β-carotene. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 130, No. 7, pp. 95–97, July, 2000     

Effect of the season on lipid peroxidation in the myocardium of rats with different resistance to hypoxia

Lipid peroxidation and the antioxidant system of the myocardium of adult male Wistar rats with low and high resistance to acute hypoxia tested by “raising” to an altitude of 11.5 km are studied in winter and in summer. It is found that the winter season is a mild stressor inducing changes in the myocardial antioxidant system and lipid peroxidation which are similar to those observed at the early stages of catecholamine stress in the summer season. In both cases alterations are more pronounced in low-resistance than in high-resistance rats. In winter, in low-resistance rats the intensity of lipid peroxidation and the activity of the antioxidant system are lower, while the ratio of their parameters (chemiluminescence data) is higher. At the same time, the levels of thiobarbituric acid-reactive substances are higher in winter in both groups. The relationship between the studied parameters and the resistance of rats to hypoxia is more obvious in winter than in summer, i.e., it is season-dependent and is also more pronounced in catecholamine stress. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N^olo 7, pp. 87–90, July, 1995 Presented by N. A. Agadzhanyan, Member of the Russian Academy of Medical Sciences     

Sex-related differences in the degree of lipid peroxidation activation and resistance to cardiovascular damage induced by stress in rats

It is shown that during stress a rapid twofold increase of erythrocyte acid resistance in rats of both sexes was followed by a 1.5-fold decrease toward the 60th min in males and the 120th min in females. In males, in contrast to females, the level of malonic dialdehyde was raised not only during stress, but also 1 and 24 hours after its completion. Stress-induced dystrophic changes of cardiomyocytes were more marked in males. The area of myocardial damage in females was almost twice as small as in males. It is assumed that the better resistance of females to stress-induced cardiovascular damage may be due to increased efficacy of antioxidant mechanisms inhibiting lipid peroxidation. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, No 4, pp. 354–357, April, 1995 Presented by K. V. Sudakov, Member of the Russian Academy of Medical Sciences     

β-Carotene-containing preparation carinat inhibits lipid peroxidation and development of renal tumors in rats treated with chemical carcinogen

The effects of pretreatment with β-carotene-containing preparation carinat on the development of renal tumors in rats receiving single intravenous injection of chemical carcinogen 3-(1-α-L-arabinopyranosyl)-1-methyl-1-nitrosourea were studied. Fourteen months after carcinogen administration, the degree of lipid oxidation in rat kidneys 2.5-fold surpassed that in animals receiving carinat in a dose producingin vivo antioxidant effect. Carinat decreased the total number of induced tumors and the incidence of mesenchymal renal tumors and suppressed the development of multiple tumors. The accumulation of lipoperoxides in the kidneys during carcinogenesis is associated with activation of free radical processes and carcinogen-induced inhibition of lipoperoxide enzymatic degradation and probably promotes renal malignancies due to co-carcinogenic action of these compounds. The data suggest that carinat-induced suppression of tumor development attests to antioxidant effects of β-carotene. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 130, No. 7, pp. 95–97, July, 2000     

Effect of pH and glutathione on lipid peroxidation in tocopherol-enriched liposomes

Tocopherol-enriched liver microsomes are more resistant to lipid peroxidation at an alkaline pH of 8.5 in comparison with microsomes incubated at pH 7.5. An alkaline pH provides conditions for two-electron oxidation of tocopherol, which causes the lipid molecule to revert to the initial state (O₂/H exchange). A possible mechanism of inhibition of lipid peroxidation within the physiological range of pH with participation of a glutathione-dependent enzyme is discussed. Translated fromByullenten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 9, pp. 268–270, September, 1995 Presented by E. I. Chazov, Member of the Russian Academy of Medical Sciences     

The leucocytic and parasitaemic profiles and immune response of rats treated with retinyl palmitate before infection with Trypanosoma brucei

The effects of oral administration of retinyl palmitate (30 000 IU/kg bodyweight) for 3 days to rats before infection with Trypanosoma brucei were investigated by examining the leucocytic and parasitaemic profiles, and the antibody response to sheep red blood cells. The pretreatment significantly (P<0.01) improved the leucocytic profile (especially the absolute lymphocyte count) from day 7 post-infection to the time of death. It also significantly delayed the onset of parasitaemia (i.e., lengthened the pre-patent period) and led to reduced levels of parasitaemia throughout the period of infection. Pretreatment significantly increased the antibody response to sheep red blood cells (P<0.01) throughout the infection, even after treatment with diminazene aceturate, to levels that more than compensated for the immunosuppressive effect of the T. brucei. Further studies are warranted on the possible use of retinyl palmitate in overcoming immunosuppression associated with trypanosome infections in man and animals in endemic areas.     

Lowering of lipid peroxidation and acute toxicity of bromobenzene by a polymeric form of zinc-metallothionein

Plasma and liver contents of malonic aldehyde are studied one day after administration of bromobenzene to mice pretreated with a polymeric form of zinc-metallothionein from rat liver. It is found that zinc-metallothionein injected in a dose of 1–4 mg/kg 5–10 min prior to injection of bromobenzene (2 g/kg, about 56% of LD₅₀) markedly lowers the malonic dialdehyde level and active toxicity of this xenobiotic. Administration of a mixture modeling Zn-metallothionein (albumin, cysteine, and zinc) in a dose of 4 mg/kg has no appreciable effect on the malonic dialdehyde level raised after bromobenzene injection, and does not change its LD₅₀. It is concluded that the protective effect of exogenous zinc-metallothionein is due to its antioxidant activity, which allows for normalization of lipid peroxidation. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 1, pp. 43–45, January, 1995 Presented by B. B. Moroz, Member of the Russian Academy of Medical Sciences     

次声作用后血浆NO、ET-1、SOD、MDA水平的变化

目的：测定8 Hz、130 dB次声不同时间暴露后大鼠血浆一氧化氮（NO）、内皮素（ET-1）、SOD、MDA水平的变化。方法：用8 Hz、130 dB的次声连续作用大鼠1、7、14、21和28 d，每天2 h，测定大鼠血浆NO、ET-1、SOD、MDA水平。结果：在暴露期间，7、14 d时大鼠血浆NO含量显著最低（P＜0.01），1 d、21 d和28 d时正常（P＞0.05）；大鼠血浆ET-1含量均明显升高（P＜0.01），7 d时升高最多，14 d时升高最少；大鼠血浆SOD活性明显降低（P＜0.01）；大鼠血浆MDA水平明显升高（P＜0.01）。结论：次声可引起大鼠血浆NO、ET-1、SOD、MDA水平的变化，发生的改变与次声暴露时间有关。     

The content of tocopherol and lipid peroxidation products in the tissues of rats with genetically determined hyperproduction of free oxygen radicals

It is shown that at the age of 2–3 months S rats with genetically determined hyperproduction of free radicals have the same content of tocopherol in the heart, epididymal fat, adrenals, liver, and liver mitochondria as Wistar rats but a lower content of plasma tocopherol. At 10–12 months, the tocopherol content in all studied tissues and organs, except the liver, is higher than in young S rats and age-matched Wistar rats. This is regarded as a compensatory response facilitating the stabilization of LPO under conditions of increased free radical formation. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 3, pp. 282–284, March, 1996     

Effect of melatonin on cyclic nucleotide content and intensity of lipid peroxidation in the hippocampus and habenula of rats exposed to acute hypoxia

Single intraperitoneal injection of melatonin in a dose of 1 mg/kg prevented accumulation of cGMP and intensification of lipid peroxidation in the hippocampus and habenula of rats exposed to acute hypobaric hypoxia (12,000 m). Changes in habenular content of cGMP suggest that melatonin prevents hypoxia-induced activation of heme-oxygenase. Translated fromByulleten' Eksperimental" noi Biologii i Meditsiny, Vol. 130, No. 8, pp. 168–171, August, 2000