Genotoxic and carcinogenic potential of 160 mycotoxins in human cells. Dr. Audebert Marc, UMR1331 Toxalim, Toulouse, France

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1 Genotoxic and carcinogenic potential of 160 mycotoxins in human cells Dr. Audebert Marc, UMR1331 Toxalim, Toulouse, France

2 Mycotoxins Mycotoxins = secondary fungal metabolites produced by different species Aspergillus Penicillium Fusarium Favorable grow conditions At the level of the fields of culture During storage Foodstuffs Processed products

3 Example of aflatoxin B1 Metabolism CYP3A4, CYP1A2 Epoxyde (8,9 exoepoxyde) AFB1 Mutations (p53 ) DNA replication.m.s : hepatocellular carcinoma is the third cause of death in the world. AFB1 was classified by IARC in groupe I as carcinogenic for human. DNA adducts formation

4 Mycotoxin problems More than 200 mycotoxins were potentially present in food Increasingly important contamination Inter-species toxicity variability Few toxicological data (notably for genotoxicity) in human cells Exposure to mixture of mycotoxins Difficulty to managed mycotoxins risk assessment for human

5 Aims of the project Analysis the toxic potential (cytotoxicity and genotoxicity) of 160 mycotoxins in human cells

6 Methods Selection of the mycotoxins found in food. Use of human cell lines with different bioactivation properties. Use of the high throughput g2ax/p3 assay to determined genotoxicity and cytotoxicity. (Khoury et Al. Arch. Tox. 2016)

7 g2ax/p3 quantification with the In Cell Western technique Determination of the genotoxicity and cytotoxicity potential in any cell type in a high-throughput manner. (Khoury et Al.Mutagenesis 2016) The ICW g2ax/p3 assay detected genotoxic compounds with different mode of action and discriminated aneugen from clastogen. The ICW g2ax/p3 assay display a better sensitivity and predictivity than other genotoxicity assays (Ames, MN, CMET ). (Khoury et Al. Arch. Tox. 2016) Efficient evaluation of genotoxicity with the g2ax ICW assay : - Pesticides (Graillot et Al., Env Mol Mutagen, 2012; Graillot et Al., Mut Res 2012) - Bisphenols (Dolo et Al., Arch Tox 2011) - PAs (Audebert et Al., Tox Letter 2010; Audebert et Al., Tox And Appl Pharma 2012) - AAs (Jamin et Al., Plos NE 2013; Chevereau et Al., Arch Tox 2017) - Pathogenic bacteria (Martin et Al., Plos Pathogen 2013) - xidized lipids (Bastide et Al., Can. Res ) - Metals (Kopp et Al. Env Mol Mutagen. 2018) - Virus, water

8 Selected mycotoxins Mycotoxins found in the alimentation, nine different families: - Aflatoxins and their precursors (12) - chratoxins (2) - Fusariotoxins: Trichothecens groupe A (8), groupe B (5) Zearalenone/Zearalanone (6) Fumonisins (3) thers fusariotoxins (21) - Mycotoxins from Alternaria (7) - Tremorgenes mycotoxins (13) - Mycotoxins isolated from Penicillium (30) - Mycotoxins isolated from Aspergillus (39) - Mycotoxins isolated from Penicillium and d Aspergillus (7) - ther mycotoxins (8)

9 Toxicity (cytotoxicity and genotoxicity) screening of mycotoxins with the g2ax/p3 assay In Cell Western technique with the g2ax and p3 biomarkers Four human cell lines, from target organs of mycotoxins: epg2 (liver) Bioactivation capacities LS-174T (colon) ACN (kidney) S-SY5Y (brain) Two biomarkers: epg2 LS-174T ACN S-SY5Y Mode of toxic action g2ax p3 g2ax p3 g2ax p3 g2ax p Cytotoxic Aneugen Direct clastogen Clastogen after bioactivation

10 acetate versiconal hemiacetal acetate Me aflatoxin M1 versiconal acetate versiconal Me Me Me sterigmatocystin versiconal Biosynthesis versicolorin A of aflatoxins versiconal averufin Me Me -methylsterigmatocystin demethylsterigmatocystin Me sterigmatocystin norsolorinic norsolorinic acid averantin averantin 5 -hydroxy-averantin 5 -hydroxy-averantin norsolorinic acid averantin 5 -hydroxy-averantin sterigmatocystin Me Me Me Me Me Me versicolorin A versicolorin demethylsterigmatocystin aflatoxin M1 A Me dihydrosterigmatocystin demethylsterigmatocystin averufanin Me versicolorin versicolorin B A sterigmatocystin dihydrodemethylsterigmatocystin Me Me Me Me N Me Me N Me Me cyclopiazonic dihydrosterigmatocystin acid versicolorin B versiconal hemiacetal acetate averufin averufin averufanin Me averufanin demethylsterigmatocystin dihydrodemethylsterigmatocystin -methylsterigmatocystin norsolorinic acid averantin 5 -hydroxy-averantin versicolorin A demethylsterigmatocystin Me Me demethylsterigmatocystin Me Me Me Me Me sterigmatocystin Me -methylsterigmatocystin Me Me aflatoxicol dihydrodemethylsterigmatocystin Me Me dihydrosterigmatocystin Me Me Me dihydrodemethylsterigmatocystin dihydrodemethylsterigmatocystin Me dihydro--methylsterigmatocystin Me Me Me Me Me -methylsterigmatocystin Me Me dihydro--methylsterigmatocystin Me -methylsterigmatocystin cyclopiazonic acid Me dihydro--methylsterigmatocystin aflatoxin B1 aflatoxin G1 Me aflatoxin B2 aflatoxin G2 Me sterigmatocystin dihydrosterigmatocystin sterigmatocystin dihydrosterigmatocystin aflatoxicol versiconal hemiacetal acetate demethylsterigmatocystin -methylsterigmatocystin aflatoxin aflatoxin B1 B1 aflatoxin G1 G1 Me dihydro--methylsterigmatocystin aflatoxin B2 B2 aflatoxin G2 G2 -methylsterigmatocystin dihydro--methylsterigmatocystin Me versiconal Me versicolorin averufanin B versicolorin B B versicolorin B dihydrodemethylsterigmatocystin Me Me Me versicolorin A aflatoxin B1 aflatoxin G1 aflatoxin B2 a Me versicolorin A dihydro--methylsterigmatocystin sterigmatocystin Me Me averufin Me dihydrosterigmatocystin Me Me Me Me Me Me Me Me dihydrodemethylsterigmatocystin Me Me dihydrosterigmatocystin dihydroste dihydro--meth N N

11 Toxicity of aflatoxins and their precursors

12 Genotoxic equivalent factor (GEF) for aflatoxins Compound GEF LS-174T GEF epg2 GEF ACN Carcinogenesis AFB AFB AFG AFG AFM AFL ST MST ND VERA NR ND AVE ND CPA ND (ND) not determined, (++) positive, (+) moderated, (-) negative (Theumer et al. Food Chem. Tox. 2018)

13 Structure of trichothecenes Groupe A Groupe B T-2 T-2 Nivalenol (NIV) Deoxynivalenol (DN) T-2 triol T-2 tetraol 3-Acetyldeoxynivalenol (3-ADN) 15-Acetoxyscirpenol (MAS) Diacetoxyscirpenol (DAS) 15-Acetyldeoxynivalenol (15-ADN) Neosolaniol (NE) NT 2 Toxin Fusarenon X (FUSX)

14 Conclusions of the project More than an half of the tested mycotoxins are genotoxic

15 Perspectives of the project Determination of the specific genotoxic mechanisms of action of mycotoxins Mutagenesis DNA adducts, oxidative stress Effect of mixture of mycotoxins (antagonism, additivity or synergy of action): Mixture of mycotoxins from same family (aflatoxins, trichothecenes ) Mixture of mycotoxins present at the same time in food Mixture of regulated mycotoxins (deoxynivalenol, zearalenone, fumonisin B1, aflatoxin B1, ochratoxin A et patuline)

16 Thank you for your attention D. Zalko L. Khoury