Sex reversal effects on Caiman latirostris exposed to environmentally relevant doses of the xenoestrogen bisphenol A

STOKER C; REY F; RODRIGUEZ HA; RAMOS JG; SIROSKI, P; LARRIERA, A; LUQUE EH; MUÑOZ DE TORO MM

GENERAL AND COMPARATIVE ENDOCRINOLOGY

Año: 2003 vol. 133 p. 287 - 296

0016-6480

Environmental contaminants known as endocrine disruptors (EDs) interfere with reproductive development and function in several species. Bisphenol A (BPA) is an estrogenic chemical that contaminate the environment and has a potential significant risk for human and wildlife. Prenatal exposure of rodents to environmentally relevant doses of BPA alters the development of the reproductive organs of male and female offspring. Species with temperature dependent sex determination (TSD) could act as sentinels of ecosystem health providing sensitive biomarkers of EDs effects. We selected Caiman latirostris as an animal model to study endocrine disruption caused by BPA. The aim of this study was to determine whether or not exposure in ovum to BPA could cause estrogen-like effects on the reproductive system of Caiman latirostris. Sex determination and gonadal histoarchitecture were the endpoints evaluated after in ovum exposure to different doses of BPA and E2. We confirmed that Caiman latirostris is a species with TSD. Additionally, we demonstrated that BPA cause estrogen-like developmental effects by reversing gonadal sex and/or altering gonadal histoarchitecture. We also showed that the endocrine disruptive effect on Caiman latirostris gonadal development dependent on the dose used. Differences in response between BPA and E2 in our in vivo system were on the order of 100 fold, this is very different to that reported for in vitro studies where differences are on the order of 10,000X or more. These results support the usefulness of Caiman latirostris, species in which sex determination is temperature dependent, as a tool in assessing estrogenic activity in vivo and as a sentinel to monitor EDs in aquatic environment. Concern regarding BPA concentration in the environment and its possible impact on wildlife populations is raised.