The role of Nrf2a in developmental toxicity induced by 3,3'-dichlorobiphenyl (PCB-11) in developing zebrafish (Danio rerio)

The environmental pollutant PCB-11 is a lower-chlorinated polychlorinated biphenyl (PCB) congener present in air and water samples. Both PCB-11 and its metabolite, 4-PCB-11-Sulfate, are detected in humans, including in pregnant women. Previous research in zebrafish (Danio rerio) has shown that 20 uM exposures to PCB-11 or 4-PCB-11-Sulfate starting at 1 day post fertilization (dpf) impede Cyp1a enzyme activity at 4 dpf, resulting in toxicity only for PCB-11 exposures. However, 0.2 uM daily exposure to 4-PCB-11-Sulfate starting at 1 dpf increases hepatic neutral lipid accumulation at 15 dpf. This research explored whether oxidative stress contributes to PCB-11 embryotoxicity via the master-regulator of the adaptive response to oxidative stress, Nuclear factor erythroid-2 (Nrf2), as well as whether Nrf2 plays a role in 4-PCB-11-Sulfate mediated metabolic endpoints.