Scientific journal
European Journal of Natural History
ISSN 2073-4972

INFLUENCE OF OXIDATIVE STRESS ON REDOX-STATE AND PERIPHERAL BLOOD HETEROPHILIC LEUKOCYTES APOPTOTIC PROGRAM REALIZATION

Zhavoronok T.V., Stepovaya Ye.A., Ryazantseva N.V., Petina G.V., Starikov Yu.V., Ageyeva T.S.
Purpose: oxidative processes and neutrophils apoptosis evaluation in acute period of community-acquired pneumonia (CAP).

Materials and methods: 34 patients with the verified diagnosis of CAP were examined, the control made 32 healthy donors. Neutrophils were released on the bi-gradient; the number of apoptotic cells and the intracellular level of oxygen active forms (OAF) were evaluated in cell cultures by the method of ductal laser cytometry; the number of oxygenized carbonyl-proteins (CP) and cytokine production (IL-8, FNOα) were defined by the IFA method; the OH group production, myeloperoxidase (MP), glutathione-peroxidase (GP), glutathione-reductase (GR), thioredoxine- reductase (TRR)  activity,  deoxidized (DG) and oxidized (OG) forms of glutathione were investigated spectrophotometrically.

Results and consideration. During the acute CAP period the production of proinfammatory cytokines IL-8, FNOα and OH group by neutrophils into the incubation medium increased (р<0,05) together with the activity increase of MP, which produced СlO- ions, that correlated with the pulmonary parenchyma inflammation intensity increase (the verification on the evidence of computerized tomography data). And with it the intracellular OAF amount in heterophilic leukocytes grew with protein oxidative modification (POM) processes promotion attended by the CP content increase and thiol-disulphide (TD) system balance shift towards oxygenized disulphide components formation. Against the OAF production increase in CAP patients the fact of total imbalance in glutathione-dependent neutrophil system has been registered, that was manifested in the GP activity inhibition, the decrease of DG amount and DG/OG integral factor characterizing the total TD potential capacity. The intracellular OG amounts´ increase in neutrophils along with insufficient activity of GR and TRR reactivating reduction potential of the cell was registered. The HS/SS change is a repair moment in the processes of proteins oxidation and there can be no reparation in other OPM variants. Thus, the ratio of deoxidized thiol groups to oxidized ones and their ability to oxidative modification (buffer capacity) are important criteria of nonspecific cell resistance and enable their effective functioning. Antioxidative protection resources exhaustion and level increase of damaging functional proteins OAF leads to the creation of an oxidative stress situation in acute inflammation effector cells themselves. The redox potential decrease could promote the acceleration (р<0,05) of lethal program of neutrophils´ apoptosis, which is registered in the acute CAP period.

Conclusions. The intra- and extracellular prooxidants production increase, POM with CP accumulation, glutathione-dependent system activity decrease against the expressed DG/OG index fall and reduction potential regeneration system´s inhibition in neutrophils are the signs of oxidative imbalance of effector cells of acute inflammation developing in CAP debut, that worsens the clinical course.

Intracellular redox- potential modulation can take part in the regulation of programmed cell death of neutrophils in OS conditions.

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.