THE RTGILL-W1 FISH CELL LINE

ENHANCED CYTOTOXICITY PRODUCED BY THE CO-EXPOSURE OF MYCOTOXINS IN THE RTGILL-W1 FISH CELL LINE

E. Bernal, A. Valdehita, M.L. Fernández-Cruz Department of Environment and Agronomy, (National Institute for Agricultural and Food Research and Technology, CSIC) 28040 Madrid, Spain fcruz@inia.es Mycotoxins are frequently present in cereals and feed and a high level of co-occurrences in the same sample are described. In the last decades the aquaculture industry has introduced plant-based ingredients as a source of protein for fish feeds. This has led to mycotoxin contaminations which can represent a hazard for fish and humans. A previous research1 conducted in the fish cell line RTgillW1 indicated that most of the fifteen assayed mycotoxins exerted a pronounced acute effect. The objective of the present work was to study the cytotoxicity of the co-occurrences of mycotoxins most frequently described in the literature in cereals and in different feeds (including fish feeds. The RTgill-W1 was exposed during 24 hours to a range of a mycotoxin concentrations (0.012-100 µg/mL) in co-exposure with the concentrations of another mycotoxin which decrease the viability by 10% or 50% (EC10 and EC50). The co-occurrences studied were deoxynivalenol (DON) + zearalenone (ZEA), DON + beauvericin (BEA); ZEA + BEA, DON + fumonisin B1 or B2; DON + enniatins A or A1 or B or B1. The cytotoxicity was evaluated with a triple cytotoxicity assay (AlamarBlue, CFDA-AM, and Neutral Red Uptake), which measures the cell metabolism at the mitochondrial level and the plasma lysosome membrane integrities, respectively. An enhanced toxicity was observed for almost all the co-exposures studied except for DON+ZEA and DON+FB2. This result points to the need to include an additional safety factor in the establishment of permissible levels of mycotoxins in fish feeds to avoid the risks of the frequent co-

exposures. 1Bernal-Algaba, E.; Pulgarín-Alfaro, M.; Fernández-Cruz, M.L. Cytotoxicity of Mycotoxins Frequently Present in Aquafeeds to the Fish Cell Line RTGill-W1. Toxins 2021, 13, 581.

Keywords: mycotoxin; cytotoxicity; co-occurrence; RTgill-W1; fish

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