Neurotoxicity of Cypermethrin in the Zebrafish retina

PARAVANI, ENRIQUE; SIMONIELLO, MA. FERNANDA; POLETTA, GISELA L.; CASCO, VÍCTOR

Santa Fe

Otro; Curso de Posgrado Actualización en Mecanismos de Daño y Reparación del ADN; 2014

Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral

Cypermethrin (Cyp) is a broad spectrum insecticide pyrethroid which acts by contact and ingestion. It provides effective control of insects and low mammalian toxicity, being used in agricultural and domestic applications. In this study, the effect of Cyp in the different layers of retinal cells of adult zebrafish was analyzed. The animals were exposed to two Cyp concentrations (0.3 µg / L and 0.6 µg / L) for 3, 6, 9 and 12 days. Treated control and exposure time for each group were used. The evaluation was made by histological techniques, comet assay (CA) and changes in enzyme activity (catalase -CAT-and superoxide dismutase -SOD). The lower concentration (0.3 µg / L) induced no significant morphological changes in retinal layers, while with 0.6 µg / L the disappearance of the plexiform layer and the outer limiting membrane is observed, as well as the detection of apoptotic figures in photoreceptors. Retinal cells exposed to both concentrations exhibit significant increases in the rates of DNA damage at day 9 and 12 compared to respective controls. Results of enzyme activity showed a decrease in CAT and SOD with the two concentrations at 9 and 12 days. This decrease could be related to the imbalance of reactive oxygen species (ROS) in vivo, generating oxidative stress in retinal cells. All this information is useful for understanding the environmental risks in aquatic systems caused by the use of Cyp.