Reproductive biomarkers responses induced by xenoestrogens in the characid fish Astyanax fasciatus inhabiting a South American reservoir: an integrated field and laboratory approach.
Field studies evaluating the effects of endocrine disruption chemicals (EDCs) on the fish reproduction are scarce worldwide. The goal of this study was to assess hepatic levels of vitellogenin (Vtg), zona radiata proteins (Zrp) and insulin-like growth factors (IGF-I and IGF-II), and relating them to reproductive endpoints in a wild fish population habiting a reservoir that receive domestic sewage, agricultural and industrial residues. Adult fish Astyanax fasciatus were sampled during the reproductive season in five sites from the Furnas Reservoir, Grande River, and Paraguay-Paraná basin. As a control to field data, fish were experimentally exposed via dietary intake, to oestradiol benzoate (OB) for 7 days. Fish from site with little anthropogenic interference showed hepatic levels of Vtg, Zrp and IGF-I and IGF-II similar to those from the non-treated experimental group. In sites located immediately downstream from the municipal wastewater discharges, the water total oestrogen was >120 ng/l, and male fish displayed increased Vtg and Zrp and decreased IGF-I levels similar to OB treated fish. In females, levels of Vtg, Zrp, IGF-I and IGF-II suggest an impairment of final oocyte maturation and spawning, as also detected by frequency of over-ripening, follicular atresia and fecundity. At the sites that receive agricultural and industrial residues, the water total oestrogen was <50 ng/l and females showed decreased Zrp and increased IGF-II levels associated to reduced diameter of vitellogenic follicles, indicating an inhibition of oocyte growth. Overall, the current study reports oestrogenic contamination impairing the reproduction of a wild fish from a hydroeletric reservoir and, the data contribute to improving the current knowledge on relationship between hepatic Vtg, Zrp and IGF-I and IGF-II, and reproductive endpoints in a teleost fish. In addition, our data point out novel reproductive biomarkers (IGF-I, IGF-II and over-ripening) to assessing xenoestrogenic contamination in freshwater ecosystems.
Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, UFMG, Belo Horizonte, C.P. 486, 30161-970, Minas Gerais, Brasil.
Paula S
PS
Prado
Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, UFMG, Belo Horizonte, C.P. 486, 30161-970, Minas Gerais, Brasil.
Ana Paula B
AP
Pinheiro
Programa de Pós-Graduação em Zoologia de Vertebrados, Pontifícia Universidade Católica de Minas Gerais, PUC Minas, Belo Horizonte 30535-610, Minas Gerais, Brasil.
Nilo
N
Bazzoli
Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, UFMG, Belo Horizonte, C.P. 486, 30161-970, Minas Gerais, Brasil. Electronic address: ictio@icb.ufmg.br.
Elizete
E
Rizzo
D000818:Animals; D015415:Biomarkers / Q000378:metabolism*; D060126:Characidae; D004527:Egg Proteins / Q000378:metabolism; D052244:Endocrine Disruptors / Q000633:toxicity*; D004958:Estradiol / Q000031:analogs & derivatives; D005260:Female; D005298:Fertility / Q000187:drug effects; D005496:Follicular Atresia / Q000187:drug effects; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D007335:Insulin-Like Growth Factor II / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008297:Male; D006080:Ovarian Follicle / Q000187:drug effects; D012098:Reproduction / Q000187:drug effects*; D014819:Vitellogenins / Q000378:metabolism
D015415:Biomarkers; D004527:Egg Proteins; D052244:Endocrine Disruptors; D014819:Vitellogenins; C423083:zona radiata protein, fish; C074283:estradiol 3-benzoate; D004958:Estradiol; D007334:Insulin-Like Growth Factor I; D007335:Insulin-Like Growth Factor II
Endocrine disruption; IGF-I; IGF-II; Over-ripening; Vitellogenin; Zona radiata proteins