Changes in the blood-brain barrier in experimental cirrhosis of the liver

Light and electron microscopic studies on Wistar rats with experimental cirrhosis produced by tetrachloromethane demonstrate strongly marked changes in the blood-brain barrier, particularly in capillaries and vascular pedicles of astrocytes. It is pointed out that destabilization of the blood-brain barrier favors the transfer of cerebral toxins and other metabolic poisons across this barrier. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 7, pp. 86–88, July, 1994 Presented by I. P. Ashmarin, Member of the Russian Academy of Medical Sciences     

Changes in the blood-brain barrier during experimental cirrhosis of the liver

Translated fromBulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 116, N ^o 12, pp. 638–641, December, 1993     

Role of superoxide dismutase in the pathogenesis of amyotrophic lateral sclerosis

Activity of cytosolic Cu²⁺/Zn²⁺-superoxide dismutase and total superoxide dismutase activity of the spinal fluid of patients with sporadic amyotrophic lateral sclerosis were measured. These parameters correlates with the form of this disease, its duration, and the severity of neurological disorders. Our findings indicate that free-radical processes are involved in the damage to motor neurons in this disease. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 127, No. 4, pp. 460–462, April, 1999     

Effect of superoxide dismutase on convulsive seizures in rat models of epilepsy

Intravenous injections of superoxide dismutase into rats with amygdaline kindling mitigated spontaneous and electrostimulation-induced epileptic seizures and raised the thresholds of electric current for their elicitation; these seizures of reduced intensity were observed during 3 days following chronic (for 6 days) treatment with this enzyme. In contrast, superoxide dismutase injections had no effect on the convulsions induced by electric shock or corazole. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 7, pp. 20–22, July, 1995 Presented by A. N. Klimov, Member of the Russian Academy of Medical Sciences     

Superoxide dismutase activity in the brain of rats prenatally treated with lead

Cu/Zn superoxide dismutase activity in the brain of offspring of female rats treated with various concentrations of lead at various periods before and during pregnancy was reduced, which indicated disturbances of the antioxidant system. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 128, No. 12, pp. 667–669, December, 1999     

Effect of antibodies to red cell superoxide dismutase on its activity in the blood of patients with rheumatoid arthritis

A relationship is revealed between the level of antibodies to superoxide dismutase and the activity, course, and form of a disease. The production of antibodies to red cell superoxide dismutase increases as the pathological process progresses. By reducing the resistance of erythrocyte membranes to reactive oxygen species, antibodies to red cell superoxide dismutase promote the development of anemia in patients with rheumatoid arthritis. The results indicate that inhibition of the active center of this enzyme by specific immunoglobulins is one of the causes of reduced activity of red cell superoxide dismutase or the lack of an appreciable increase in its activity during hyperproduction of reactive oxygen species. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 10, pp. 391–393, October, 1995 Presented by A. B. Zborovskii, Member of the Russian Academy of Medical Sciences     

Pharmacokinetics of new nootropic acylprolyldipeptide and its penetration across the blood-brain barrier after oral administration

Pharmacokinetics of GVS-111, a new acylprolyldipeptide with nootropic properties and its penetration across the blood-brain barrier were studied in rats using HPLC. It was found that the dipeptide is absorbed in the gastrointestinal tract, enters the circulation, and penetrates through the blood-brain barrier in an umodified state. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 129, No. 4, pp. 426–429, April, 2000     

Erythrocyte superoxide dismutase activity in rats subjected to a toxic regime of intermittent hyperbaric oxygenation

The development of toxic manifestations in rats exposed to hyperoxia is accompanied by a significant decrease in the activity of erythrocytic superoxide dismutase (SOD). Incubation of hemolysates from control animals with H₂O₂ (10^–3 M) or cumene peroxide (1.6\10^–4 M) also led to a marked decrease in the initial SOD activity. The decrease in the initial SOD activity during hyperoxia is thus evidently connected with the formation of peroxidation products in the cells.Department of Hyperbaric Oxygenation, All-Union Research Institute of Clinical and Experimental Surgery. Department of Biochemistry, Medico-Biological Faculty, Second Moscow Medical Institute. (Presented by Academician B. V. Petrovskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 8, pp. 959–961, August, 1976.     

Application of cultured endothelial cells of the brain microvasculature in the study of the blood-brain barrier

Summary The endothelial cells of the brain microvasculature provide both physical and enzymatic barriers to the exchange of molecules between the extracellular fluid environment of the brain and the systemic circulation. To better understand these barrier properties and the factors that influence them at the cellular level, an in vitro model of the blood-brain barrier has been developed using primary cultures of bovine brain microvessel endothelial cells. The focus of the present paper is on the procedures associated with the isolation, culturing, and maintenance of bovine brain microvessel endothelial cells. Experimental applications of the cell culture model in studying the blood-brain barrier and efforts directed at improving the current cell culture model are also discussed.     

Effect of exogenous superoxide dismutase and 1,4-diazobicyclo-[2.2.2]octane on the resistance of mice to acute oxygen poisoning

A single intravenous injection of a purified preparation of superoxide dismutase (1000 units) simultaneously with catalase (0.5 mg) or without it into mice did not protect the animals against the toxic action of 100% oxygen under a pressure of 5 atm. Intraperitoneal injection of 1,4-diazobicyclo[2.2.2]octane (6 mg) under these conditions prolonged the preconvulsive period and increased the survival rate of the mice. It is suggested that singlet oxygen is formed during hyperoxia.Department of Biochemistry, Medico-Biological Faculty, N. I. Pirogov Second Moscow Medical Institute. Department of Hyperbaric Oxygenation, All-Union Scientific-Research Institute of Clinical and Experimental Surgery, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR S. S. Debov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 2, pp. 147–150, February, 1977.     

Effect of thymosin fractions on the development of toxic swelling edema of the brain

Rat experiments have shown that thymosin fractions V and VI elicit an antiedemic effect by normalizing predominantly the density of brain tissues, the effect being independent of the preparation dose. It is demonstrated that a high dose of fraction VII has a pronounced antiedemic effect. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, № 3, pp. 290–291, March, 1994 Presented by P. V. Sergeev, Member of the Russian Academy of Medical Sciences a     

Accumulation of exogenous histone in rat brain parenchyma

In vivo histoautoradiographic study of cerebral accumulation of exogenous histone after its intracarotid infusion to anesthetized rats with intact liver and animals with experimental cirrhosis showed that histone penetrates brain capillary endotheliocyte membranes and gets into the nervous tissue. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 130, No. 7, pp. 63–66, July, 2000     

Accumulation of exogenous histone in rat brain parenchyma

In vivo histoautoradiographic study of cerebral accumulation of exogenous histone after its intracarotid infusion to anesthetized rats with intact liver and animals with experimental cirrhosis showed that histone penetrates brain capillary endotheliocyte membranes and gets into the nervous tissue. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 130, No. 7, pp. 63–66, July, 2000     

Antiedematous effect of the preparation Polyosm in brain ischemia

The effect of the preparation Polyosm (polyethylene oxide 400) on cerebral edema (impedance measurements) and cerebral circulation is studied in brain ischemia caused by ligation of the left common carotid artery and reduction of blood flow through the right common carotid artery to 25% of the original level. The preparation markedly reduces cerebral edema and induces transient improvements in cerebral circulation. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 122, No. 10, pp. 410–412, October, 1996     

Biochemical and electron paramagnetic resonance study of the iron superoxide dismutase from Plasmodium falciparum

Recombinant iron-containing superoxide dismutase (Fe-SOD) from Plasmodium falciparum was produced in a SOD-deficient strain of Escherichia coli, purified and characterised. The enzyme is a dimer, which contains 1.7 Fe equivalents and is sensitive to hydrogen peroxide (H(2)O(2)). Electron paramagnetic resonance (EPR) analysis showed two different signals, reflecting the presence of two different types of high-spin Fe sites with different symmetries. The role of the W71 residue during inactivation by H(2)O(2) of the P. falciparum Fe-SOD was studied by site-directed mutagenesis. First, the W71V mutation led to a change in the relative proportion of the two Fe-based EPR signals. Second, the mutant protein was almost as active as the wild-type (WT) protein but more sensitive to heat inactivation. Third, resistance to H(2)O(2) was only slightly increased indicating that W71 was marginally responsible for the sensitivity of Fe-SOD to H(2)O(2). A molecular model of the subunit was designed to assist in interpretation of the results. The fact that the parasite SOD does not belong to classes of SOD present in humans may provide a novel approach for the design of antimalarial drugs.     

Effect of the adrenocorticotropic hormone fragments and atriopeptides on the development of toxic brain edema

A fragment of adrenocorticotropic hormone and its analog Semax exhibit pronounced antiedematous activity in rats and cause dehydration of the arbitrarily intact hemisphere. By contrast, atriopeptides protect the hemisphere, but exhibit no antiedematous activity. These peptides may be involved in the pathogenesis of toxic brain edema. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 122, No. 11, pp. 521–523, November, 1996     

Assessment of the toxic and protective effects of initiators and inhibitors of free radical reactions using a wild-type strain ofEscherichia coli and a strain deficient for superoxide dismutase

The toxic effects of H₂O₂, paraquat, and oxidized low density lipoproteins are more expressed on superoxide dismutase-deficientE. coli strains than on its wild-type strains, and the effect of tert-butyl-hydroperoxide is less dependent on the presence or absence of this enzyme in the bacterium, whereas that of bleomycin does not depend on it at all. The toxicity of the agents increases in the following series: H₂O₂<oxidized low density lipoproteins<tert-butyl-hydroperoxide <paraquat≪bleomycin. A culture ofE. coli strains AB 1157 and JI 132 may be used for assessing the toxic effect of prooxidants, and anE. coli JI 132 culture with oxidative stress induced by prooxidants as a test system for detecting the potential antioxidants and assessing the mechanism of the action. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o , pp. 74–79, January, 1996 Presented by A. I. Archakov, Member of the Russian Academy of Medical Sciences     

Effect of dioxydine and cyclophosphane on lipid peroxidation and superoxide dismutase and catalase activities in C57Bl/6 and BALB/c mice

Twenty-four hours after intraperitoneal injection of cyclophosphane (40 mg/kg) and dioxydine (300 mg/kg) to C57Bl/6 mice, liver catalase activity dropped by 29 and 23%, respectively. In BALB/c mice, dioxydine (but not cyclophosphane) reduced catalase activity by 24%. Superoxide dismutase activity was lowered by cyclophosphane (but not dioxydine) in BALB/c mice, and by both dioxydine and cyclophosphane in C57Bl/6 mice (by 24 and 86%, respectively). The level of 2-thiobarbituric acid (TBA)-reactive lipid peroxidation (LPO) products in the liver of BALB/c mice treated with cyclophosphane and dioxydine increased 1.4- and 2.1-fold, respectively, while in C57Bl/6 mice it did not differ from the control. The initial rate ofin vitro-induced LPO in BALB/c mice receiving cyclophosphane and dioxydine increased 1.5- and 4-fold, respectively. In C57Bl/6 mice both cyclophosphane and dioxydine inhibited the accumulation of TBA-reactive LPO products. On the whole, animals of the C57Bl/6 strain are more resistant to the LPO-inducing action of mutagens than BALB/c mice, despite the fact that the latter are characterized by a higher activity of antioxidant enzymes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, No. 5, pp. 528–532, May, 1996