The aim of this study was to evaluate the effect of serum selenium on PPAR-γ and the selected proinflammatory cytokines (IL-1β, IL-6, TNF-α) in relation to depressive symptoms and obesity in middle-aged women. The research procedure was as follows: a survey was performed using the authors' questionnaire and the BDI, anthropometric measurements, and the analysis of blood for the levels of selenium, cytokines, and genetic analysis of the PPAR-γ polymorphism (n = 443). It was found that the BMI increased along with the concentration of IL-6. No moderating effect of selenium was observed, although the cut-off values for "p" were established for IL-β*Se (p = 0.068) and IL-6*Se (p = 0.068), so there was a potential association with these two markers. At high selenium levels, the effect of higher IL-β levels on a decrease in BMI was stronger, as was the effect of an increase in IL-6 levels on an increase in BMI. No effect of selenium on PPAR-γ was found in relation to depressive symptoms and obesity. Higher selenium levels may have a beneficial effect on BMI even at high IL-β concentrations, however, at high IL-6 concentrations, this effect was not observed. Selenium levels had no impact on depressive symptoms.
Keywords: cytokines; depression; middle-aged women; obesity; selenium.