Background Benzoapyrene (BaP), an xenobiotic compound, can induce dysfunction of related transcription regulators, but the underlying mechanism has not been clarified yet.
Objective This study aims to investigate the effects of BaP exposure during pregnancy on aryl hydrocarbon receptor (AhR) expression and the interaction between AhR and aryl hydrocarbon receptor nuclear translocator 2 (ARNT2).
Methods Sixty healthy SD rats were selected and mated 1:1. The pregnant rats were divided into a blank group, an olive oil group, and 10, 20, and 40 mg·kg-1 BaP groups, with 6 rats in each group. At gestational day 17-19, the 30 pregnant rats were intraperitoneally injected with BaP, olive oil, or received no treatment as designed. The expression of AhR and its interaction with ARNT2 in the cortex of offspring rats on postnatal day 1 (PND1) and postnatal day 7 (PND7) were measured by Western blotting and Co-Immunoprecipitation assay.
Results According to the results of Western blotting: in the PND1 offspring cortex, the AhR relative expression level was increased in the 40 mg·kg-1 BaP group (1.91±0.74) compared with the blank group (1.00±0.00) (P < 0.05); in the cortex of PND7 offspring, the AhR relative expression levels were increased in the 20 mg·kg-1 BaP group (1.92±0.56) and the 40 mg·kg-1 BaP group (1.77±0.62) (P < 0.05). The results of Co-Immunoprecipitation assay showed that, on PND1, the binding amounts of ARNT2 to AhR were increased in the 10, 20, and 40 mg·kg-1 BaP groups (1.74±0.27, 2.55±0.40, and 1.26±0.24, respectively) compared with the blank group (1.00±0.00) (P < 0.05); on PND7, the bindings amounts were increased in the 20 and 40mg·kg-1 BaP groups (1.75±0.59 and 1.83±0.49) compared with the blank group (1.00±0.00) (P < 0.05).
Conclusion Prenatal BaP exposure can cause elevated offspring AhR expression and enhance AhR-ARNT2 interaction.
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