Interference of pesticides with Brain Aromatase Expression of a native fish (Jenynsia Multidentata)

BONANSEA ROCÍO INÉS; GUYÓN, N.; WUNDERLIN,D.A.; BISTONI, M.; AMÉ, M.V.

Cracovia

Congreso; 3rd Young environmental scientists meeting Krakow; 2013

Sociedad de Toxicología y Química Ambiental (SETAC)

Many natural and synthetic chemicals present in the environment are suspected of exerting a number of adverse effects on the organism, leading to endocrine disruption. Several indications exist that interference with the aromatase CYP19 system might lead to malfunctioning of the reproductive system, which is the most frequently reported symptom of endocrine disruption in fish. For teleosts fish, two cyp19 genes (cyp19a1 and cyp19a2) have been described. CYP19A1, commonly known as gonadal aromatase, is preferentially expressed in the ovary and plays an important role in sex differentiation and oocyte growth. CYP19A2, called brain aromatase, is constitutively expressed in the brain and is probably involved in the development of the central nervous system, survival, morphology, synaptogenesis, and sex behavior. The aim of the present study was to evaluate changes in cyp19a2 expression in brain of Jenynsia multidentata exposed to environmentally relevant concentrations of pesticides. For this purpose, adult female fishes were exposed over 96 hours to 40ng/L of Cypermethrin and 400ng/L of Chlorpyrifos singly and in technical mixture. Additionally, the same mixture (40ng/L of Cypermethrin plus 400ng/L of Chlorpyrifos) of a commercial product was tested. Total RNA was extracted from brain tissue by the guanidine thiocyanate?phenol chloroform extraction method and nonspecific reverse transcription was performed with an Oligo (dT)15 primer. Quantitative polymerase chain reaction was performed using β-actin as housekeeping gen. Our results showed that Chlorpyrifos and the commercial mixture were able to inhibit significantly cyp19a2 expression while Cypermethrin and the technical mixture did not vary from the control. As a result, it could be hypothesized that Chlorpyrifos and its commercial mixture with Cypermethrin could cause or contribute to estrogen-related disorders in J. multidentata. Moreover, the differences observed between the technical and commercial mixtures reinforce the need of further studies at other pesticide concentrations and formulations.