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M V Bilenko

Publications and source records attributed to M V Bilenko.

61 records · Page 4Linked to original sources
PubMedDate not supplied

[Study of the mechanisms of action of lipid peroxidation products on the permeability of bilayer lipid membranes].

It has been shown that introduction of the fraction of phosphatydylethanolamine enriched with primary products of peroxidation-hydroperoxides-into bilayer lipid membrane (BLM) results in the rise of permeability of BLM towards H+ and K+ ions. The effect depends on the background permeability of the membrane and on the introduction method of the fraction enriched with hydroperoxides (FEHP) into monolayer or into both layers of BLM. Absence of the effect while including hydroperoxides into the membrane monolayer with low background conductivity and growth of BLM conductivity when introducing FEHP into both monolayers of the membrane permits a substantiation of the "Cluster" mechanisms of the membrane permeability increase with the accumulation of phospholipid hydroperoxides.

Electric Conductivity↗
PubMedDate not supplied

[Role of peroxidation in destruction of membrane lipids under conditions of liver ischemia].

Alterations in phospholipid and fatty acid composition were studied in homogenates, mitochondrial, microsomal and nuclear fractions during intensification of lipid peroxidation under conditions of liver tissue ischemia. Increase in content of lipid hydroperoxides and decrease in content of arachidonic acid were observed in lipids of all the membranes studied. Content of individual phospholipids altered depending on their susceptibility to peroxidation. In ischemia content of total lipids and phospholipids was decreased. The data obtained suggest the important role of peroxidation in impairment of membrane lipids under conditions of ischemia.

Animals↗
PubMedDate not supplied

[Comparative evaluation of the cytotoxic effect of hydrogen peroxide and tumor necrosis factor alpha on nonischemic and ischemic endothelial cells].

We studied cytotoxic effects (CTE) induced in confluent cultures of human umbilical vein endothelial cells (HUVEC) by initiators of free-radical reactions (FRR): H2O2 (10(-6)-10(-9) M), recombinant human tumor necrosis factor-[symbol; see text] (TNF-alpha, 0.05-100 ng/ml), and a combination of TNF-alpha with low-density lipoproteins (LDL, 100 microgram/ml). HUVEC were incubated with these substances for 6 or 24 h in parallel tests performed under aerobic (CO2-incubator) and ischemic conditions (a mixture of 95% N2 + 5% CO2 in RPMI-1640 medium containing no substrate additives, growth factor or protein). HUVEC viability was determined by counting cells adherent to the bottom of wells after 24 h of reincubation under aerobic conditions in the growth medium (Plating Efficiency Index). The data showed that: 1) CTE of these compounds were dose-dependent (H2O2 and TNF-alpha) and time-dependent (TNF-alpha); 2) CTE of FRR initiators and CTE of ischemia were synergistic, that is, their combination produced a greater decrease HUVEC viability than any substance examined or ischemia alone; 3) CTE of TNF-alpha observed in experiments in substrate-deficient, protein-free medium was considerably stronger than in the growth medium; 4) a combination of TNF-a and LDL caused a stronger CTE on HUVEC than either factor alone, and this synergism was more pronounced during incubation under ischemic conditions. Thus, the data indicate that FRR initiators and TNF-alpha + LDL particularly increase the severity of ischemic injuries of EC and therefore they can be factors which in hypercholesterolemic patiens predispose vascular wall to atherosclerosis.

Cells, Cultured↗