GLUTAREDOXIN AND GLUTATHIONE AS THE MOLECULES REGULATING BREAST EPITHELIAL CELL PROLIFERATION UNDER ROSCOVITINE-INDUCED OXIDATIVE STRESS
The objective: to determine the role of glutathione and glutaredoxin in regulation of proliferation of HBL-100 human breast epithelial cells under roscovitine-induced oxidative stress. Material and methods. The HBL-100 cell line (human breast epithelial cells) was used in the study. The cell culture was incubated in the presence and absence of roscovitine in the final concentration of 20 mcmol for 18 h. The production of reactive oxygen intermediate, the cells distribution among cycling state and the amount of Annexin V positive cells were determined using flow cytometry. The concentrations of reduced and oxidized glutathione and protein SH groups were measured by spectrophotometry. The levels of glutaredoxin, cyclin E and cyclin-dependent protein kinases were estimated by Western blotting with monoclonal antibodies. Results and discussion. The effects of roscovitine in the HBL-100 cells resulted in cell cycle block in G2/М phases with the decreased level of cyclin-dependent protein kinase 2 and activation of oxidative stress. It was accompanied by the elevated generation of reactive oxygen intermediate and the decrease in the concentrations of reduced glutathione and protein SH groups. We found out that roscovitine has anti-proliferative effects that are determined not only by the impact on the cyclin level, cyclin conformations and cyclin-dependent protein kinase activity, but also by the shift in the intracellular oxidant/antioxidant ratio. The model of free radical oxidation proposed in our work enabled to establish the role of the glutathione/glutaredoxin system in impairing cell cycle phase progression. It indicated a possibility to regulate cellular proliferation through modulating functional properties of redox-dependent proteins in different pathologies accompanied by oxidative stress.
About Authors (Correspondence):
Shakhristova E.V. – candidate of medical sciences, assistant professor of the chair for biochemistry and molecular biology with the course of clinical laboratory diagnostics, e-mail: firstname.lastname@example.org