Induction of CYP1A in Caretta caretta lymphocytes exposed to PAHs and PBDEs.

The Mediterranean population of the loggerhead turtle (C. caretta), a threatened species, may be especially subject to ecotoxicological hazard due to high levels of contaminants in this sea, one reason being its long mean life expectancy. The need to develop sensitive non destructive biomarkers to investigate the health status of this species has focused attention on the possibilities offered by different non destructive biological materials. The aim of this study was to investigate protein expression and induction of CYP1A in loggerhead turtle lymphocytes. Lymphocytes were extracted from blood of turtles hospitalised in a recovery center in Italy and cultured using RPMI-based complete medium. Cultures were treated with two doses of PAHs (benzo(a)pyrene and B-naphthoflavone) and two doses of a mix of 27 PBDEs. Western blot was used to test presence and induction of CYP1A in the different treatment groups and to compare the induction potential of PAHs and PBDEs. CYP1A was detected in all lymphocyte cultures at a molecular weight of about 59 kDa. Cultures treated with PAHs showed clear induction of CYP1A, though no evident differences were found between the two doses. Cultures treated with PBDEs showed induction of CYP1A that increased with dose and was several fold higher than for PAH treatments. The results of this study are the first evidence of induction of CYP1A by contaminants in loggerhead turtle lymphocytes, and represent an important starting point for in vivo application of this biomarker of exposure.