Tag Archives: lipid peroxidation

Actomyosin ATPase activity of skeletal muscles and the markers of tissue damage in the blood of rats under prolonged chronic alcoholization

Yu. V. Tseyslyer1, О. M. Podpalova2, N. Е. Nurishchenko1, V. S. Маrtyniuk1

1ESC Institute of Biology, Taras Shevchenko National University of Kyiv, Ukraine;
e-mail: yuliya.tseysler@gmail.com,
2Bogomolets National Medical University, Kyiv, Ukraine;
e-mail: olgapodpalova@gmail.com

The activity of creatine kinase and indices of lipid metabolism in the blood and also actomyosin ATPase activity of skeletal muscles of rats under chronic 8-month alcohol abuse were investigated. It is shown that actomyosin K+-ATPase activity of skele­tal muscles increases from two months of ethanol use, but actomyosin Mg2+-ATPase activity decreases during 6-8 months of alcoholization. From two months of ethanol use the creatine kinase activity, as an enzyme marker of muscle tissue damage, statistically significantly increases during all the period of the animals alcoholization. The level of total lipid increases after two months of alcohol consumption (in blood plasma by 30% and in erythrocyte mass by 65%). For longer periods of alcoholization (4-8 months) the level of lipids remains almost the same, whereas in erythrocyte mass it does not differ from control values. The level of diene conjugates in the blood plasma reduces and the amount of ketone derivatives of fatty acid residues increases that points to the inhibition of some components of the antioxidant system that control detoxification of hydroperoxides of fatty acids and also to activation of free radical damage of tissues. There were no significant changes of lipid peroxidation level in erythrocyte mass at any stage of alcoholization.

Functions of tocopherols in the cells of plants and other photosynthetic organisms

V. M. Mokrosnop

M. G. Kholodny Institute of Botany, National Academy of Sciences of Ukraine, Kyiv;
e-mail: VictoryM6@yandex.ua

Tocopherol synthesis has only been observed in photosynthetic organisms (plants, algae and some cyanobacteria). Tocopherol is synthesized in the inner membrane of chloroplasts and distributed between chloroplast membranes, thylakoids and plastoglobules. Physiological significance of tocopherols for human and animal is well-studied, but relatively little is known about their function in plant organisms. Among the best characterized functions of tocopherols in cells is their ability to scavenge and quench reactive oxygen species and fat-soluble by-products of oxidative stress. There are the data on the participation of different mechanisms of α-tocopherol action in protecting photosystem II (PS II) from photoinhibition both by deactivation of singlet oxygen produced by PS II and by reduction of proton permeability of thylakoid membranes, leading to acidification of lumen under high light conditions and activation of violaxanthin de-epoxidase. Additional biological activity of tocopherols, independent of its antioxidant functions have been demonstrated. Basic mechanisms for these effects are connected with the modulation of signal transduction pathways by specific tocopherols and, in some instances, by transcriptional activation of gene expression.

Laureates of the Palladin Prize of the National Academy of Sciences of Ukraine (1997–1998)

R. P. Vynogradova, V. M. Danilova

Palladin Insitute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: valdan@biochem.kiev.ua

V. A. Baraboi received the O.V. Palladin prize in 1997 for the series of works “The role of lipid peroxidation in the mechanism of ionizing radiation damage and stress”. O. Iu. Petrenko, O. M. Sukochov, L. P. Kravchenko were awarded the O.V. Palladin prize in 1998 for the series of works “The function of intracellular structures in isolated hepatocytes depending on the metabolic status and the effects of low temperatures”.