Cytochrome P4501A-activity in rainbow trout (Oncorhynchus mykiss) hepatocytes after exposure to PCB#126 and astaxanthin: In vitro and in vivo studies

The aim of this study was to investigate whether astaxanthin alone, or in combination with PCB#126, induces the hepatic cytochrome P4501A-system in rainbow trout hepatocytes. Primary hepatocyte cells were exposed in vitro to different concentrations of PCB#126 with or without supplementation of astaxanthin. The expression of CYP1AmRNA and CYP1A-activity (EROD) were measured. In the in vivo study, newly hatched rainbow trout yolk-sac fry were injected with different concentrations of PCB#126 with or without additional astaxanthin. Thirty-six days after injection, hepatic CYP1A-activity was measured. Dose-dependent EROD-inductions were recorded in both bioassays after exposure to PCB#126. No significant changes in CYP1AmRNA content or CYP1A-activity were obtained after exposure to astaxanthin alone, or in combination with PCB#126, nor were any synergistic effects observed between PCB#126 and astaxanthin.