Evaluation of the neuropharmaceutical carbamazepine in the steroidogenic pathway and in the hepatic and gonadal morphology of Astyanax lacustris

Abstract

The reproductive process in vertebrates is controlled by the hypothalamic-pituitarygonadal (HPG) axis, which regulates gonadal development, but can be influenced byexternal factors capable of altering the functioning of this axis. Some of these externalfactors can be the contaminants of emerging concern (CECs), which are compoundscapable of causing harm to the environment and organisms present in the affected area,both in the short and long term. The neuropharmaceutical carbamazepine (CBZ) isconsidered a CEC, and its effects will be studied in this project, aiming to deepen theinteractions that occur in the pituitary-gonadal axis and in the hepatic tissue of the nativeteleost Astyanax lacustris (yellow-tailed lambari) exposed to CBZ. Morphologicalanalyses of the liver and testicles, as well as gene expression of vitellogenin (vtg) andcytochrome P450 (cyp1a) in the liver, and enzymes from the testicular steroidogenicpathway, and androgen (ar) and estrogen (er) receptors in the pituitary, will be used asbiomarkers. Mature males (n = 96) will be exposed for 7 days (n = 8/aquarium, intriplicate) in the following experimental groups: 1) control with vehicle (DMSO -dimethyl sulfoxide); 2) 250 ng L-1of CBZ; 3) 500 ng L-1of CBZ; and 4) 1250 ng L-1ofCBZ, considered environmentally relevant concentrations. Since there is negligenceregarding disposal policies concerning CECs, ecotoxicology studies can provide a betterunderstanding of the concentrations present in the environment and their effects onorganisms.