Activation of the enzymes of phase I (CYP2B1/2) and phase II (SULT1A and COMT) metabolism by 2,2′,4,4′-tetrabromodiphenyl ether (BDE47) in the pig ovary

The aim of the current study was to determine metabolism of polybrominated diphenyl ether (BDE-47) in the porcine ovary. We analyzed the activity and expression of enzymes involved in phase I (CYP1A1 and CYP2B1/2) and phase II (SULT1A and COMT) of BDE-47 metabolism. Basal CYP1A1 and CYP2B1/2 activity increased during culture. BDE-47 had no effect on CYP1A1, however increased CYP2B1/2 activity after exposure for 6 h. Basal SULT1A activity was 2.5 fold lower than that of COMT, and both proteins were stable during culture. BDE-47 increased SULT1A after exposure for 6 h, and COMT activity after exposure for 24 and 48 h. BDE-47 had no effect on the expression of all investigated enzymes. In conclusion, fast activation of CYP2B1/2 and late activation of COMT (with a very low basal SULT1A activity) indicates a possible action of locally produced hydroxylated metabolites prior to their detoxification.

► We analyzed the activity and expression of enzymes involved in phase I and phase II of BDE-47 metabolism.
► We showed that BDE-47 induce the first phase (CYP2B1/2) and second phase (SULT1A1 and COMT) of metabolism by affecting the activity of enzymes, without an effect on protein levels.
► For the first time we demonstrated SULT1A protein levels in pig ovary measured by immunoblot and ELISA analyses.