REDOX STATUS AND CELL MEMBRANE ALTERATIONS OF CIRCULATING LEUKOCYTES AND ERYTHROCYTES IN ABNORMAL UTERINE BLEEDING

Abstract

Aim. To analyze the eryptosis degree, the state of cell membranes and redox status of circulating red blood cells and leukocytes in patients with abnormal uterine bleeding and its combination with hypothyroidism.

Materials and methods. Patients, 74 women aged 18 to 49 years, were examined, which were divided into 3 groups: group I - women with abnormal uterine bleeding (AUB) (24 patients); group II - with AUB and thyroid pathology (30 patients, of whom 18 women had primary hypothyroidism and 2 - secondary hypothyroidism); group III - control group (20 healthy women, who had never had menstrual irregularities).

Eryptosis of circulating erythrocytes was assessed by flow cytometry using annexin V staining and 2′,7′-dichlorodihydrofluorescein diacetate (H2DCFDA) staining. Fluorescent probes O1O (2-(2¢-hydroxy-phenyl)-5-phenyl-1,3-oxazole) and PH7 (2-(2¢-hydroxy-phenyl)-phenanthro[9,10-d]-1,3-oxazole) were used to characterize changes in phospholipid bilayers of circulating erythrocytes and leukocytes. Lysed blood samples were stained with antibodies to CD45, 7-aminoactinomycin D and H2DCFDA to analyze the redox status of circulating viable leukocytes.

Results. Annexin V staining revealed eryptosis activation in females with abnormal uterine bleeding combined with hypothyroidism. In addition, in these patients, oxidative stress developed in red blood cells, evidenced by an increase in intracellular reactive oxygen species (ROS) levels. Oxidative stress was accompanied by changes in the physico-chemical properties of erythrocyte membranes, namely a decrease in membrane hydration and an increase in lipid order, which can indicate enhanced lipid peroxidation. These changes were observed in women with abnormal uterine bleeding alone, however, to a lesser extent. In this study, the redox state of leukocytes and phospholipid bilayers of their cell membranes were not affected in the patients from both groups.

Conclusions. Abnormal uterine bleeding combined with hypothyroidism is associated with eryptosis activation, oxidative stress development in erythrocytes and changes in the physico-chemical properties of phospholipid bilayer of cell membranes in red blood cells.