Environmental pollution affects molecular and biochemical responses during gonadal maturation of Astyanax fasciatus (Teleostei: Characiformes: Characidae)

TOLUSSI, C.E.; GOMES, A.D.; KUMAR, A.; RIBEIRO, C.; LO NOSTRO, F.; BAIN, P; DE SOUZA G.; DA CUÑA, R.; HONJI, R.; GUIMARAES MOREIRA, R.

ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY

ACADEMIC PRESS INC ELSEVIER SCIENCE

Lugar: Amsterdam; Año: 2018 vol. 147 p. 926 - 934

0147-6513

Endocrine disrupting compounds (EDCs) have the potential to alter fish reproduction at various levels of organization.The aim of this study was to assess the impact of a natural environment with heavily anthropogenicinfluence on the physiological processes involved in reproduction in the freshwater fish lambari (Astyanaxfasciatus) using different biomarkers. Adult males and females were collected in different seasons from twodistinct sites in the same watershed: Ponte Nova Reservoir (PN) considered a pristine or small anthropogenicinfluence reference point; and Billings Reservoir (Bil), subjected to a large anthropogenic impact. Biologicalindices, such as hepatosomatic index and gonadosomatic index (GSI), gonadal histomorphology, fecundity, andbiomarkers such as plasma levels of estradiol (E2) as well as hepatic gene expression of its alfa nuclear receptor(ERα), were analyzed. Hepatic vitellogenin (VTG) gene expression was evaluated in both sexes, as an indicator ofxenoestrogen exposure. Females collected at PN presented a typical annual variation reflected in GSI, whereasfor those sampled at Bil the index did not change through the seasons. The higher concentration of E2 in malescollected at Bil during spring/2013, together with the detection of VTG gene expression, suggest the presence ofEDCs in the water. These EDCs may have also influenced fecundity of females from Bil, which was higher duringwinter and spring/2013. Gene expression of ERα and ovarian morphology did not differ between fish from bothsites. Water conditions from Bil reservoir impacted by anthropic activity clearly interfered mainly with biomarkersof biological effect such as plasma E2 levels and absolute and relative fecundity, but also altered biomarkersof exposure as VTG gene expression. These facts support the notion that waterborne EDCs are capable ofcausing estrogenic activity in A. fasciatus.