Benzo(a)pyrene induced adverse pregnancy outcomes by affecting the expression of IL-18 and IL-1RN in placenta

Inflammatory cytokines can destroy the immune balance and lead to adverse pregnancy outcomes. Benzo (a) pyrene (BaP) may induce premature delivery through leading inflammatory reaction. We screened out inflammatory factors related to adverse pregnancy outcomes through bioinformatics analysis. Then we verified the correlation between adverse pregnancy outcomes caused by BaP and abnormal expression of those inflammatory factors.

The Gene Expression Omnibus (GEO) database was used to analyze by R to screen the inflammatory genes related to adverse pregnancy outcomes. Based on the established BaP exposure animal model, the expression of key cytokines in placenta was detected by immunohistochemistry.

According to the data analysis of GEO database, the expression of IL18, IL18BP and IL18R was up-regulated, while the expression of IL1RN was down regulated in the adverse pregnancy outcome group. BaP exposure significantly increased the rate of adverse pregnancy outcome in pregnant golden hamsters, and also significantly interferes with the process of embryonic development. Meanwhile, the expression of IL18, IL18BP and IL18R in placenta was increased, while the expression of IL1RN protein was decreased, consistent with the mRNA expression level gathered by bioinformatics analysis.

BaP may induce the inflammatory reaction to cause adverse pregnancy outcome by regulating the expression of IL18, IL18BP, IL18R and IL1RN. Our findings provide experimental basis for the prevention of adverse pregnancy outcome caused by BaP.