High fetal bisphenol A exposure enhances IL22 secretion: A proinflammatory cytokine

Ozel Yuruker,¹ Ceyhun Dalkan,² Murat Uncu,³ Osman Yetkin,³ Arzu Babayigit,⁴ Nerin N. Bahceciler Onder²

Affiliations:
¹ Department of Immunology, Faculty of Medicine, University of Kyrenia, Kyrenia, Cyprus
² Department of Pediatrics, Faculty of Medicine, Near East University, Nicosia, Cyprus
³ Department of Biochemistry, Faculty of Medicine, Near East University, Nicosia, Cyprus
⁴ Department of Pediatrics, Faculty of Medicine, University of Kyrenia, Kyrenia, Cyprus

Abstract

Background: Bisphenol A (BPA) is an industrial product, widely used in human consumed types of equipment that can be transmitted orally, by inhalation or through dermal absorption and is detectable in many body fluids including cord blood. A correlation between BPA concentration in maternal serum and cord blood has been demonstrated previously, suggesting a possible transfer of BPA via the transplacental path.
Objective: Our objective is to determine the impact of cord blood BPA level on cytokine responses.
Methods: In this cross-sectional study, healthy pregnant women who delivered healthy newborns followed by the Obstetrics and Gynecology Department between September 2016 to June 2017 were enrolled. Cord blood samples were obtained and BPA and IL4, IL5, IL10, IL17, IL22, IFN gama and TGF beta levels were studied by ELISA.
Results: Among 197 deliveries, 176 of them were included in the study. Due to lack of cut-off value, BPA levels were stratified as percentiles. No statistically significant difference was detected in comparison of cytokine levels based on BPA concentrations below and above the 25^th and 50^th percentiles. Significantly higher IL22 levels (p = 0.007) and increased ratio of IL22/TGFβ (p = 0.04) were detected in those with BPA level above 75^th percentile (> 19.16 ng/ml) compared to the below group.
Conclusions: This in vivo real-life study demonstrated that very high BPA levels in cord blood of expectant mothers enhances IL22 secretion in cord blood which is a proinflammatory cytokine. Studies evaluating long term immunological effects on those highly exposed newborns are necessitated.
Key words: Cord blood, cytokines, Interleukin 22, maternal exposure, newborn