Drugs and nanocompounds toxicity screening in zebrafish model

PRIETO MJ; CALIENNI MN; IGARTUA DE; FEAS DA; MARTINEZ CS; SIRI M; CHARAMONI NS; ALONSO SDV

Congreso; FESBE 2014 - XXIX Reunião Anual, Federação de Sociedades de Biologia Experimental.; 2014

Toxicity screening of new drugs and nanocompounds is now the defining step whether a drug goes into clinical trial or not. In pursuing so, using an innovative model organism like the zebrafish, reduces the time and the cost required for the drug development process, increasing the compound success rate and decreasing the failures ratio due to adverse side effects, throughout the drug research and development process. Toxicity research focuses on: Cardiotoxicity, teratogénesis, acute toxicity (LD50), neurotoxicity and epilepsy model. Methods Lethal dose 50 and teratogenicity: Evaluation of acute toxicity LD50 of embryos was performed studying the effect of different formulations. On the other hand, sublethal and teratogenic effects were evaluated (ISO 1995 and 15088:2007). Morphological changes: The larvae were fixed to study the morphology after the treatments by optical microscopy. Neurotoxicity: Larvae were placed individually in multidishes at 28 °C. Spontaneous swimming activity recorded for 15´ through a detection system of infrared beams (WMicrotracker, DesignPlus, Argentina) (Airhart et al., 2007, Prieto et al., 2012 and 2013, Selderslaghs et al., 2013). In addition, histology sections of fixed larvae were performed, and then stained with hematoxylin ? eosin to observe possible morphological changes (Prieto et al., 2012 and 2013). Cardiotoxicity: fish were set on a concave slide with carboxymethylcellulose and heart rates were filmed for 15 ´´ by light microscopy. The results were expressed as beats per minute (Airhart et al., 2007, Prieto et al., 2012, 2013). Results In trials with zebrafish embryos and larvae, severe teratogenic effect with the drug misoprostol, ethanol and valproic acid was observed. However, copper sulfate, produced no teratogenicity, only lethal effect. Cationic PAMAM (DG4) and anionic (DG4,5) as model nanoparticles were used. In DG4,5 no toxicity in embryos and larvae were observed until 20 µM. However, cardiotoxicity was determined at 48 hours post exposure in larvae at concentrations greater than 5 µM. In embryos treated with DG4 no teratogenic effect was observed, but LD50 at 48 h of 0.21 µM was determined. In larvae neurotoxicity and severe morphological changes were observed from 0.25 µM on with significant tissue ulcerations. Finally, cardiotoxicity was determined in all tested concentrations (0.032 to 0.5 µM). Conclusion Drugs and dendrimers as model of nanoparticles were studied. In this work, general toxicity was determined, also organ toxicity and teratogenic effects. These studies, used as preclinical studies, will be complemented by rodent.