Effects Of Ochratoxin A, Zearalenone And α-zearalenol On Proliferation And Oxidative Damage Of Hep G2

This study was carried out to investage the combined effect of three commonmycotoxins of food or feed on proliferation and oxidative damage of Hep G2by usingthe isobologram analysis and factorial analysis.Experiment Ⅰ: The aim of the present study was to investigate the cytotoxicity ofcombined mycotoxins of ochratoxin A (OTA), zearalenone (ZEA), and/orα-zearalenol (α-ZOL). The cytotoxicity of two or three combined mycotoxins wasevaluated on human Hep G2cells using tetrazolium salt (MTT) assay andisobologram analysis. Our results demonstrated the significant cytotoxic effects of thetwo-toxin combination and the three-toxin combination on Hep G2cells in a time-and concentration-dependent manner. The combined indexes (CI) were2.73–7.67forOTA+ZEA and1.23–17.82for OTA+α-ZOL after24h,48h, and72h of exposureat all inhibit concentration (IC) levels (IC10–IC90), indicating an antagonism. The CIsof ZEA+α-ZOL were1.29–2.55after24h and72h of exposure (IC10–IC90),indicating an antagonism. The CIs of ZEA+α-ZOL were0.74–1.68after48h ofexposure, indicating antagonism (IC10–IC40), additive (IC50–IC70), or synergism(IC80–IC90) effects. The CIs were1.41–14.65for OTA+ZEA+α-ZOL after24h,48h,and72h of exposure (IC10–IC90), indicating an antagonism.Keywords: ochratoxin A; zearalenone; α-zearalenol; Isobologram; Hep G2; cytotoxicityExperiment Ⅱ: The objective of this study was to investigate the combined effectsof ochratoxin A (OTA), zearalenone (ZEA) α-zearalenol (α-ZOL) on Hep G2cellsand explore the cytotoxicity mechanism. Three combinations (OTA×ZEA,OTA×α-ZOL and ZEA×α-ZOL) was designed in this trial.3×3factorial analysisdesign was applied in each combination. Nine groups were adopted to investigate thecombined cytotoxicity of three levels of OTA (0μM,6μM and12μM), three levelsof ZEA (0μM,30μM and60μM) and three levels of α-ZOL (0μM,15μM and30μM) in each combination after48h of exposure. The cytotoxicity of two combinedmycotoxins was evaluated by using the estimated marginal means. Our resultsdemonstrated the cytotoxicity of two combined mycotoxins indicate an antagonism incombinations of OTA×ZEA and OTA×α-ZOL. And the activities of intracellular SODand GSH-Px, the content of intracellular MDA and GSH all indicate an antagonism incombinations of OTA×ZEA and OTA×α-ZOL. After exposure of ZEA×α-ZOL the cytotoxicity of two combined mycotoxins indicate an antagonism in lowerconcentration and indicate a synergism in higher concentration, and the activities ofintracellular SOD and GSH-Px, the content of intracellular MDA and GSH indicate anantagonism in lower concentration and indicate a synergism in higher concentration.There was a significant correlation between the cytotoxicity and the oxidative damage(SOD, MDA, GSH-Px and GSH) in all combinations (P <0.05). The results showedthat the combined cytotoxicity indicates an antagonism, and oxidative damage is oneof the pathway of the cytotoxicity.