The emerging Fusarium toxin enniatin B: in-vitro studies on its genotoxic potential and cytotoxicity in V79 cells in relation to other mycotoxins

Abstract

The Fusarium metabolite enniatin B is now recognized as a frequent contaminant of grains used for human foods and animal feeds. Yet, so far very limited data are available on its toxicity and that of other emerging Fusarium mycotoxins (Jestoi M, 2008, Crit Rev Food Sci Nutr 48:21-49). Thus, the mutagenic/genotoxic potential of enniatin B was investigated in a battery of short-term tests, and its cytotoxicity compared with that of several other mycotoxins. No mutagenicity was detected in the Ames assay with four Salmonella typhimurium strains, and in the HPRT (hypoxanthine guanine phosphoribosyl transferase) assay with V79 cells, in either the presence or absence of an external metabolizing enzyme system (rat liver S9). For other types of genotoxicity, i.e., clastogenicity and chromosomal damage, studied in V79 cells by means of alkaline single-cell gel electrophoresis (Comet) assay and micronucleus assay, no significant genotoxic potential of enniatin B was revealed. However, the Fusarium metabolite exerts pronounced time- and concentration-dependent cytotoxic effects in V79 cells as determined by Alamar Blue reduction and by neutral red uptake assays. For instance, IC20 and IC50 values determined for enniatin B by neutral red assay for 48-h exposure are 1.5 μM and 4 μM. These values are higher than those of the more potent Fusarium toxin deoxynivalenol (IC20 0.7 μM, IC50 of 0.8 μM), but clearly lower than the IC values of several other mycotoxins tested in parallel. Their ranking of cytotoxicity in V79 cells was as follows: deoxynivalenol > enniatin B > patulin > ochratoxin A > zearalenone > citrinin. Moreover, enniatin B was found to induce nuclear fragmentation, a sign of apoptosis, already at low submicromolar concentrations. In summary, despite an apparent lack of mutagenic and genotoxic activity, enniatin B can cause pronounced cytotoxicity in mammalian cells, detectable at low micromolar concentrations.

Enniatin A1 ve B1 Mikotoksinlerinin Ames Salmonella Mikrozom Testi ile Mutajenitesi

“…Enniatins have got various biological activities [5,14,15] . These properties make them candidate compounds for further development as drugs [2,16] . For these reasons; evaluating the mutagenic, cytotoxic, antimicrobial effects of enniatin A1 and B1 is important.…”

“…in Ames Salmonella Microsome Test [1] Ebru YILMAZ Enniatins are fungal metabolites produced by several species of Fusarium, and were first isolated in 1947 by Gäumann et al [1,2] . Enniatins are members of a family of fungal N-methylated cyclic hexadepsipeptides and consist of three residues of D-2-hydroxyisovaleric acid alternating with three of N-methyl branched-chain L-amino acids such as valine, leucine, or isoleucine.…”

“…They are also anthelmintic, cytotoxic and phytotoxic activities [2,[9][10][11] . Although they can accumulate in Fusariuminfected grain, enniatins have not been associated with any animal disease outbreaks nor been shown to cause disease in experimental animals [3] INTRODUCTION  İletişim (Correspondence)  +90 312 4845635/150  beyzi@gazi.edu.tr that Enniatins have important impact on human health and they can cause outbreaks in humans and animals [12] .…”

“…Enniatins exert potent cytotoxic activity against cancer cell lines [5,14] , and can act also as potent inhibitors of an ABC membrane transporter related to multidrug-resistance [15] . These properties make them candidate compounds for further development as drugs, particularly as potent cytotoxic effects against several cancer cell lines [2,16] .…”

Presence of Fusarium emerging mycotoxins in tiger-nuts commercialized in Spain

“…However, so far very limited data are available on ENs and BEA toxicity. The cytotoxicity of the ENa was determined in lung fibroblast cells (V79) by the neutral red uptake (NR) assay (Behm, Degen, & Föllmann, 2009;Follmann, Behm, & Degen, 2009), and by Alamar Blue assay (Follmann et al, 2009). Similarly, the rat hepatoma (H4IIE), human hepatoma (HepG2) and rat glioma (C6) cell lines were used to determine cytotoxic effects of EN A 1 , B and B 1 using the tetrazolium salt (MTT) assay (Watjen et al, 2009).…”