Gene Expression Pattern of Antioxidant Enzymes and its Relation to Oxidative Damage and Genotoxicity in Caiman latirostris Hatchlings Exposed to Pesticide Formulations During Development.

ODETTI, L.; PARAVANI, E.; LÓPEZ GONZÁLEZ EVELYN C.; SIMONIELLO, MF; POLETTA GISELA L.

Santa Fe

Congreso; 25th Working Meeting of the Crocodile Specialist Group, Santa Fe, Argentina May 7th to 10th 2018.; 2018

PROYECTO YACARE / IUCN-SSC Crocodile Specialist Group (CSG)

The loss and fragmentation of natural habitat due to agricultural expansion has caused that wild populations of Caiman latirostris in Argentina become threatened by the constant exposure to pesticides. In previous studies, we demonstrated genotoxicity, oxidative damage and imbalances in antioxidant (AO) enzymes after exposure to different pesticide formulation by topication on the eggshell and through nest material. The aim of the present study was to analyze if alteration observed in the AO enzyme activity involve a modification of their gene expression patterns and its relation with oxidative damage to lipids, DNA and genotoxicity. Two identical experiments (E1 and E2) were carried out in consecutive years, where eggs of C. latirostris coming from different clutches were distributed in 6 groups of 12 and 15 eggs, respectively. The treatments were as follows: negative control (NC) treated with distilled water; vehicle control (VC) treated with ethanol; three groups exposed to Cypermethrin (CYP -Atanor ®, 0.12%), Chlorpyrifos (CPF -Lorsban *, 0.8%) and Glyphosate (RU-Roundup ® Full II, 2%) formulations, and one last group exposed to the ternary mixture of the three formulations (M- 0.12% + 0.8% + 2%, respectively). The concentrations applied for each pesticide formulation corresponded to that recommend for field application in soy crops. After hatching, blood samples were taken from each animal and the following biomarkers were applied: activity of the antioxidant enzymes Catalase (CAT) and Superoxide dismutase (SOD) and the expression of the corresponding genes; lipoperoxidation by Thiobarbituric acid reactive substances (TBARS), DNA damage and specific base oxidation through the standard and modified Comet assay (CA); and chromosome damage by the micronucleus test (MN). Results showed a statistically significant increase in oxidative DNA damage, DNA damage index and FMN for RU, CYP, CPF and M respect to their corresponding controls (p