The experimental study of the pathogenic role of NADPH-oxidase in the thyroid gland tissues

ABSTRACT

The objective of the study was to compare the NADPH/ H₂O₂ system and the expression of enzymes in the culture of thyroid gland cells, depending on the sex.

Material and methods. The thyroid gland was collected from adult female donors (n=20) and men (n=15). The cells were washed twice with HBSS and centrifuged at 1000 × g for 5 minutes, and then cultured to 106 cells in 0.5 ml culture medium per well in 24-well plates (Thermo Fisher Scientific, USA). H₂O₂ levels in the cells were determined quantitatively using a hydrogen peroxide sensor Premo™ Orp1-roGFP (Life Technologies, USA) according to manufacturer’s instructions.  Statistical analysis of the results was carried out using Statistica 6.1 (StatSoft, Inc., USA).

Results. We found that the expression of DUOX1 and NOX4 in the thyroid gland was significantly higher in women than in men (1.5 times, p<0.05). Expression of  DUOX2 in female cells was 1.5 times higher than in men, but statistically significant (p=0.06). We have found that the thyroid gland of women produces a significantly higher H₂O₂ content than the male gland cells (p<0.05). The expression of DUOX1 and NOX4 is significantly higher in cells derived from the female thyroid gland than in cells derived from males. H₂O₂ levels were also higher in cells derived from female thyroid gland than in male cells.

Conclusion. As a result of our experiment, the expression of DUOX1 and NOX4 is significantly higher in cells derived from the female thyroid gland than in cells derived from males. We have shown during the experiment that NOX4 is regulated both at the transcription level and at the level after transcription, and the level of sustained-release NOX4 mRNA does not accurately reflect the content and function of the NOX4 protein. Chronic effects on the female thyroid gland at higher concentrations of H₂O₂ can potentially cause many adverse effects.

Keywords: thyroid gland, NADPH oxidase, DUOX, hydrogen peroxide, oxidative stress.

Corresponding author:
Anna TITKOVA
Department of Clinical Pathophysiology, Topographic Anatomy and Operative Surgery, Kharkiv Medical Academy of Postgraduate Education, Ukraine
E-mail ann.titkov@gmail.com, phone +38098 44 58 948