Bìofìzičnij Vìsnik

5-15

Authors: O. V. Vashchenko, N. A. Kasian, V. A. Pashynska, M. V. Kosevich, A. O. Sadchenko, D. N. Tishko, T. V. Tishko, V. P. Titar, L. N. Lisetski

Intermolecular interactions between decamethoxinum (DEC) and acetylsalicylic acid (ASА) have been studied in the phospholipid-containing systems of escalating complexity levels. The host media for these substances were solvents, L-α-dipalmitoylphosphatidylcholine (DPPC) membranes, and samples of human erythrocytes. Peculiar effects caused by DEC-ASА interaction have been observed in each system using appropriate techniques: (a) DEC-ASА non-covalent complexes formation in DPPC-containing systems were revealed by mass spectrometry with electrospray ionization; (b) joint DEC-ASА action on DPPC model membranes led to increasing of membrane melting temperature Tm, whereas individual drugs caused pronounced Tm decreasing, which was demonstrated by differential scanning calorimetry; (c) deceleration of DEC-induced haemolysis of erythrocytes under joint DEC-ASА application was observed by optical microscopy.

24-33

Authors: A.S. Khrebtova, N.A. Gladkovskaya, E.G. Bereznyak, E.V. Dukhopelnikov, A.V. Fomin, A.V. Zinchenko

An interaction of actinocin derivatives Act II and Act III with DNA is studied by differential scanning calorimetry and spectrophotometry. The equilibrium concentrations of intercalational and external types of complexes in Act – DNA systems at different relative DNA concentration are calculated from spectrophotometric titration data. The binding parameters for each type of actinocin derivatives – DNA complexes are obtained. The heat capacity curves of Act – DNA complexes were obtained at different relative ligand concentrations. Calorimetric study achieved that intercalation binding type leads to increase of enthalpy, entropy and melting temperature of DNA, while the external type induces the rise of the helix thermal stability only. The comparison of helix – coil transition parameters of DNA in the complexes with actinocin derivatives and proflavine is performed. The effect of ligands on DNA melting parameters correlates to binding constants obtained by spectrophotometry.

43-51

Authors: N.О. Bodnarchuk, N.P. Harasym L.I. Petrukh, D.I. Sanagurski

The aim of work was to study the influence of flurenizyd (antimicrobial, antituberculosis, antichlamydia, immunomodulatory, antioxidant, hepatoprotective, anti-inflammatory medicine) on the antioxidant homoeostasis of loach embryos (Misgurnus fossilis L.) during early embryogenesis. Glutathioneperoxidase and glutathione-S-transferase activity was studied under the action of flurenizyd in concentrations 0.01; 0.05; 0.15; 1; 5; 15 mM, at the embryos of loach on the stage of development of the first (2 blastodmeres), fourth (16 blastodmeres), sixth (64 blastodmeres), eighth (256 blastodmeres), tenth (1024 blastodmeres) division of zygote (before the stage of de-synchronization). The two-factor analysis of variance was conducted to figure out the degree of flurenizyd influence, time of development and miscellaneous factors on activity of the enzymes of cell’s glutathione antioxidant defence system. It was shown that flurenizyd violates work of glutathioneperoxidase on all stages of development of loach embryos in particular predetermines the increase of their activity on the stage of development of 2, 16 and 256 blastomeres. The investigated antibiotic violates work of glutathione-S-transferase in the process of early embryogenesis of loach embryos Misgurnus fossilis L. In a maximal concentration (15 мМ) flurenizyd decreases activity of enzyme, starting from the initial stages of development of loach embryos. Two-factor analysis of variance indicated, that on glutathioneperoxidase and glutathione-S-transferase activity of loach embryos considerable influence is made by the miscellaneous factors, like external factors affecting the development of embryos. Time of development, in a greater degree, influences the work of glutathioneperoxidase during early embryogenesis, compared to flurenizyd that indicates indirect influence of the investigated antibiotic on glutathioneperoxidase. Considerable influence of flurenizyd on glutathione-S-transferase activity testifies its direct effect on a structure of the enzyme.