STUDY OF CITRININ TOXIC EFFECTS AND ITS MECHANISM BOTH IN VITRO AND IN VIVO USING ZEBRAFISH EMBRYOS.

Citrinin (CIT) is a mycotoxin frequently found in cereals with toxicity mainly leading to kidney damage. However, CIT toxicity mechanisms have not been yet fully investigated. We aimed to study CIT toxicity using both 3D cultures (innovative tool), and a zebrafish model. For in vitro studies, we obtained 3D spheroids from SH-SY5Y cells and exposed them to CIT for 24, 48 and 72h. We observed an increase in ATF4 and CHOP gene expression revealing endoplasmic reticulum stress. LAMP2, which is related with lysosomes, also showed an increasing trend. Regarding oxidative stress, we measured a decrease in ROS production after CIT exposure. We also observed a cell cycle arrest in G2/M phase. Our in vivo studies highlighted differences in the lethal doses being the LD50 255 ± 10.10 µM CIT at 72h, and 140.5 ± 21.7 µM CIT at 96h. 100% of the embryos showed malformations at the highest CIT concentration (300 µM), while no malformations were found at the lowest one (50 µM). We measured enhanced expression of genes related to apoptosis (apaf1, cas3 and bax), antioxidant activity (gpx), necrosis (ripk3) and inflammation (IL-8, CXCL-CIC). Similarly to the results obtained in 3D cultures, we observed a decrease in ROS production in zebrafish exposed to CIT. In conclusion, our approach allowed to more accurately recapitulate and study CIT behavior, based on the development of a general model for mycotoxins toxicity studies, for data quality improvement and tailored public health's risk assessments. Acknowledgements: This work was funded through a project from the Spanish Ministry of Science and Innovation (PID2020-115871RB-100) and also supported by the European Research Council Starting Grant (ERC-StG) MICRONEX (UERI17, PI: E. Cimetta). Moreover, FJ Martí-Quijal thanks Universitat de Valencia for the pre-doctoral grant "Atracció de Talent". [ABSTRACT FROM AUTHOR]