Scientific journal
European Journal of Natural History
ISSN 2073-4972

EVALUATION OF NEUTROPHILIC AND ERYTHROCYTIC PROTEINS’ OXIDATIVE MODIFICATION IN OXIDATIVE STRESS CONDITIONS

Zhavoronok T.V., Stepovaya Ye.A., , Petina G.V., Starikov Yu.V., Ryazantseva N.V. Ageyeva T.S.
Protein molecules are not only objects, but also participants of regulation processes of cells´ oxidative metabolism, the imbalance of which is registered in case of oxidative stress (OS) formation. 

The purpose is to detect the features of neutrophilic and erythrocytic proteins oxidative modification (POM) processes on the model of OS, which is formed in acute period of community-acquired pneumonia (CAP).

Materials and methods. 47 patients with the verified CAP diagnosis have been examined; the control group was made up of 32 healthy donors matching on age and sex. Neutrophils were released on the Ficoll-Paque density bi-gradient; plasma was collected; erythrocytes were washed out and hemolysate was prepared (1:10). The oxidized carbonyl group proteins were detected in neutrophils by the enzyme immunodetection method. In erythrocytes the proteins´ carbonylation level, superoxide dismutase (SOD), catalase, glutathione peroxidase (GP) activity, deoxidized glutathione (DG) content were determined by spectrophotometric methods. The bitirosin formation and tryptophane oxygenation was evaluated in blood plasma by the fluorimetric method; the SOD, catalase activity, lipid peroxidation (LPO) products composition - diene (DC) and triene (TC) conjugates, malondealdehyde (MDA).

Results and considerations. In CAP patients in vivo the OS formation signs were registered. The LPO activation was attended by the increase of peroxide cascade toxicants in blood plasma: the DC, TC, MDA indexes were higher than the control ones (р≤0,01) against the background of catalase, SOD antioxidant enzymes´ activity decrease (р≤0,01). The LPO products´ excess lead to the mobilization and following degradation of antioxidants, creating their deficit in cells. The DG level in erythrocytes decreased at the GP, SOD, catalase activity combined inhibition against those in the control (р≤0,05), being indicative of these cells´ reduction potential inhibition. In parallel, the restoration capabilities of disulfide cross-links, provoking the inhibition of a range of key SH-containing enzymes, turned out to be suppressed in red blood cells. The oxidative metabolism imbalance in the CAP debut promoted the activation of POM processes: the carbonylation increased (р≤0,05) both in acute inflammation effector cells (neutrophils) and in target cells (erythrocytes). Simultaneously the carbonylated proteins amount in plasma increased; the proteins´ oxidizability in vitro in conditions of incubation with the Fenton system components appearing to be increased: the carbonyl proteins increase was higher than in the group of control (р≤0,05). In the OS conditions at CAP the non-repair bitirozin cross-links and oxidized tryptophan - redox sensitive amino acids´ oxidation products, accumulation in plasma was registered.

Conclusion

The accumulation of POM carbonyl products in plasma and blood cells, DG content and antioxidant enzymes decrease testifies to the expressed oxidative imbalance, developing in the CAP debut, in the system of functional proteins of the cell, that influences the pulmonary parenchyma state and worsens the disease course.

The article is admitted to the International Scientific Conference "Development prospects of higher school science", Sochi (Dagomys), 20-23th September, 2007, came to the editorial office on 09.11.07.