Cytokine profile features in women with reproductive disorders exposed to excessive environmental contamination with hydroxybenzene

Abstract

Excessive activity of cytokines, as well as their deficiency, promote a regulatory imbalance of immune system, which may cause persistent inflammation and, as a consequence, loss of pregnancy. The purpose of our work was to study the role of cytokine expression in the development of endometriosis in women exposed to excessive environmental contamination with hydroxybenzene. The study involved 106 women of reproductive age, divided into 4 groups according to two criteria: the presence or absence of reproductive disorders (endometriosis), as well as levels of blood contamination with hydroxybenzene compared to the reference ranges. The groups of women were comparable in age, ethnicity, and social status. The level of phenol in blood was measured by gas chromatography, and the cytokine levels were determined by enzyme immunoassay. The use of parametric and nonparametric statistical criteria as well as adjustments for multiple Bonferoni comparisons, allowed us to establish significant differences between the groups, according to the levels of IL-1β, IL-8, IL-10. The expression of interleukin 8 (IL-8) in women with endometriosis was found to be significantly higher than in healthy ones. At the same time, the observed features of IL-8, interleukin 1β (IL-1β) expression correlate with the overproduction of interleukin 10 (IL-10) associated with excessive contamination of bio-environments with hydroxybenzene. The results of using non-parametric correlation analysis of the Spearman data revealed a positive correlation between IL-10 production and hydroxybenzene levels in the blood, as well as inverse relationship between IL-10 and IL-8 expression. Thus, evidence has been obtained of the involvement of exogenous estrogen hydroxybenzene in development of reproductive disorders, probably, formed under active participation of increased anti-inflammatory IL-10 cytokine, which, by antagonism to proinflammatory mediators (e.g., IL-8), seems to promote apparent transition from acute phase of endometriosis to chronic disorder, thus reducing the reproductive potential of women. It is known that IL-8 expression significantly correlates with development of endometriosis, but excessive phenol exposure may increase the anti-inflammatory IL-10 expression, thereby suppressing the activity of IL-8. Suppressed activity of proinflammatory cytokines by phenol may lead to chronic inflammation and impaired reproductive functions.