Tag Archives: erythrocytes

Nitrate and nitrite in drinking water affect antioxidant enzymes in erythrocytes of rats

E. Sierra-Campos1, M. A. Valdez-Solana1, M. I. Campos-Almazán1,
C. Avitia-Domínguez2, J. L. Hernández-Rivera1, J. A. De Lira-Sánchez1,
G. Garcia-Arenas3, A. Téllez-Valencia2

1Faculty of Chemical Sciences, Campus Gómez Palacio, University Juarez of Durango State, Gomez Palacio, Durango, Mexico;
e-mail: ericksier@gmail.com;
2Faculty of Medicine and Nutrition, Campus Durango, University Juarez of Durango State, Durango, Mexico;
3Faculty of Health Sciences, Campus Gómez Palacio, University Juarez of Durango State, Gomez Palacio, Durango, Mexico

The present study evaluated the effect of short term intake of nitrite and nitrate drinking water on the antioxidant system and membrane damage of rat erythrocytes. Wistar rats were randomly divided into three groups as follows; the group I received only distilled water ad libitum; the group II was given water with nitrate (a dose of 124 mg/kg of nitrate-nitrogen) as drinking water and the group III was given nitrites dissolved in distilled water in a dose of 150 mg/kg for 7 days. At the end of the study, group III rats showed a significant decrease in activities of glutathione peroxidase (GPx), glucose 6-phosphate dehydrogenase (G6PDH) and catalase (CAT), while in group II rats, the activity of GPx and CAT were significantly reduced, but no significant changes in glutathione reductase activity and peroxynitrite levels were observed. On the other hand, malondialdehyde (MDA) was increased in both groups with respect to group I. Also, our major results indicate that all treatments changed methemoglobin levels and osmotic fragility in comparison to group I rats. The intensity of alterations was found more severe in rats of group III, followed by rats of group II. It can be concluded from these observations that nitrate or nitrite leads to alterations in the erythrocytes antioxidant defense status mainly throughout NADPH relate enzymes.

Participation of proteinkinase CK2 in regulation of human erythrocytes plasma membrane redox system activity: relative contribution of Са(2+)-dependent and Са(2+)-independent mechanisms of its activation

I. N. Iakovenko, V. V. Zhirnov, A. P. Kozachenko,
O. V. Shablykin, V. S. Brovarets

Institute of Bioorganic and Petroleum Chemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: brovarets@bpci.kiev.ua

Involvement of protein kinase CK2 (2.7.11.1) in modulation of live cells trans-plasma membrane electron transport was first discovered. Using human erythrocytes a decrease of plasma membrane redox system (PMRS) activity is shown under the action of specific protein kinase CK2 inhibitors.
Using inhibitory analysis the activity regulation of human erythrocytes PMRS by Ca2+-dependent and Ca2+-independent mechanisms were investigated. It was shown that functional Ca2+-antagonists (nitrendipine and calmidazolium) significantly increased, and functional Ca2+-agonists to some extent reduced (calcimycin) or did not affect (Bay K 8644) the trans-plasma membrane electron transport in these cells. In all cases of calcium signaling the system modifications inhibition of kinase CK2 is also accompanied by significant reductions of erythrocytes PMRS activity. Against the background of kinase CK2 inhibition the mentioned influence activity of nitrendipine and Bay K 8644 on PMRS does not change, that of calmidazolium increases and of calcimycin is not revealed. Obtained results demonstrate the inhibitory effect of Ca2+ and calmodulin on human erythrocytes PMRS and the activation of this system by protein kinase CK2 mainly through Ca2+-independent mechanisms. Some participation of calmodulin in PMRS activity regulation by kinase CK2 is discussed.

The effect of selenium haemoglobin an resistant for photooxidative processes

 T. M. Huseynov, F. R. Yahyayeva, R. T. Guliyeva

Institute of Physics, National Academy of Sciences of Azerbaijan;
e-mail: thuseynov@physics.ab.az

On an example of a guinea pig it is shown that exogenous selenium (0.5 mg Na2SeO3 per 1 kg of the animal weight) during 2-hour exposition in the animal organism increases the resistance to the photo-induced oxidation of haemoglobin in erythrocyte lysates without additional stimulation of glutathione peroxidase mechanism of haemoglobin protection by exogenous selenium. It is shown that the saturation of haemoglobin fractions by selenium hampers the oxidative modification of haemoglobin.
Using pregnancy of women as a natural model­ of selenium-deficiency condition, it has been shown that physiological debilitation of saturation erythrocytes with selenium, including haemoglobin fractions of lysates erythrocytes caused debilitation of resistance of haemoglobin to photo-oxidative destruction. Under these conditions not only activity of enzyme glutathione peroxidise in erythrocyte lysates, but also the peroxidase activi­ty of haemoglobin (in the presence of glutathione) were decreased. It is more characteristic of erythrocyte lysates with a less content of selenium, i.e. for the erythrocytes of women on late terms of pregnancy that testifies to the presence of certain relation between haemoglobin saturation with selenium and its peroxidase activity (in the presence of glutathione).