title: Developmental exposure to endocrine disruptor chemicals alters follicular dynamics and steroid levels in Caiman latirostris.
abstract: Human and wildlife are exposed at critical periods of development to endocrine disruptor chemicals (EDC) that may be responsible for reproductive disorders. To test the hypothesis that in ovum exposure to EDC at a critical period for gonadal organogenesis alters post-hatching folliculogenesis and steroidogenesis in Caiman latirostris, we studied the impact of in ovum exposure to 17 beta-estradiol (E2), bisphenol A (BPA), endosulfan (END) and atrazine (ATZ) on gonadal differentiation, follicular dynamics and circulating levels of steroid hormones in neonatal and juvenile caiman. Since C. latirostris is a species with temperature dependent sex determination, eggs were incubated at male (33 degrees C) or female (30 degrees C) producing temperatures and the effect of EDC was evaluated. Neonatal ovaries exhibited germ cells mainly located in clusters evidencing proliferative activity and type I to III follicles. Juvenile ovaries exhibited germ cells and advanced stages of pre-vitellogenic follicles. Prenatal exposure to the highest doses of E2 (1.4 ppm) or BPA (140 ppm) overrode male temperature effect on sex determination. Neonatal females produced by sex reversion lacked type III follicles, while females prenatally exposed to the lowest doses of E2 (0.014 ppm) and BPA (1.4 ppm) or ATZ (0.2 ppm) showed an increase in type III follicles. Juvenile caiman prenatally exposed to E2 or BPA showed an augmented incidence of multioocyte follicles. Neonatal female caiman exposed in ovum to E2 or BPA had higher estrogen serum levels whereas exposure to E2, BPA, ATZ and END decreased T levels. Present data demonstrates that exposure to EDC during gonadal organogenesis alters follicular dynamics and steroid levels later in life. These effects might have an impact on caiman fertility.
authors.affiliation: Laboratorio de Endocrinología y Tumores Hormonodependientes, School of Biochemistry and Biological Sciences, Universidad Nacional del Litoral, Casilla de Correo 242, 3000 Santa Fe, Argentina.
authors.forename: Cora
authors.initials: C
authors.lastname: Stoker
authors.forename: Pablo M
authors.initials: PM
authors.lastname: Beldoménico
authors.forename: Verónica L
authors.initials: VL
authors.lastname: Bosquiazzo
authors.forename: Marcelo A
authors.initials: MA
authors.lastname: Zayas
authors.forename: Florencia
authors.initials: F
authors.lastname: Rey
authors.forename: Horacio
authors.initials: H
authors.lastname: Rodríguez
authors.forename: Mónica
authors.initials: M
authors.lastname: Muñoz-de-Toro
authors.forename: Enrique H
authors.initials: EH
authors.lastname: Luque
mesh_terms: D000489:Alligators and Crocodiles / Q000378:metabolism*; D000818:Animals; D000831:Animals, Newborn; D001280:Atrazine / Q000494:pharmacology; D001559:Benzhydryl Compounds; D049109:Cell Proliferation / Q000187:drug effects; D052244:Endocrine Disruptors / Q000494:pharmacology*; D004726:Endosulfan / Q000494:pharmacology; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D005298:Fertility / Q000187:drug effects; D006540:Herbicides / Q000494:pharmacology; D007306:Insecticides / Q000494:pharmacology; D009865:Oocytes / Q000187:drug effects / Q000254:growth & development / Q000648:ultrastructure; D006080:Ovarian Follicle / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D010636:Phenols / Q000494:pharmacology; D013256:Steroids / Q000378:metabolism*; D000098826:Bisphenol A Compounds
chemical_list: D001280:Atrazine; D001559:Benzhydryl Compounds; D052244:Endocrine Disruptors; D004726:Endosulfan; D004958:Estradiol; D006540:Herbicides; D007306:Insecticides; D010636:Phenols; D013256:Steroids; C006780:bisphenol A; D000098826:Bisphenol A Compounds