Effect of vitamin E and polyphenols on ochratoxin A-induced cytotoxicity in liver (HepG2) cells.
It has been shown that oxidative damage contributes to the wide range of toxic effects of the mycotoxin ochratoxin A (OTA). Therefore, we examined the effects of alpha-tocopherol (alpha-TOC) and different polyphenols--catechin (CAT), daidzein (DAI), epicatechin (EC), epigallocatechin gallate (EGCG), genistein (GEN), and quercetin (QUE)--on OTA-induced cytotoxicity in HepG2 liver cells. Incubation of HepG2 cells with increasing concentrations of OTA resulted in a dose- and time-dependent cytotoxicity as measured by the neutral red assay. Half lethal concentrations (LC50) of OTA were 35 and 10 microM after 48 and 72 h incubation, respectively. Incubation of HepG2 cells with alpha-TOC as well as with different polyphenols (exhibiting different antioxidant potency as determined by the FRAP, TEAC and DPPH assays) did not counteract OTA-induced cytotoxicity. These findings indicate that OTA may exert its toxic effects by affecting other hepatic mechanisms than those directly modulated by alpha-TOC and polyphenols.
Hundhausen
Christoph
C
Institute of Human Nutrition and Food Science, Christian-Albrechts-University of Kiel, Olshausenstr. 40, 24098 Kiel, Germany.
Bösch-Saadatmandi
Christine
C
Augustin
Kay
K
Blank
Ralf
R
Wolffram
Siegfried
S
Rimbach
Gerald
G
D000975:Antioxidants / Q000494:pharmacology*; D045744:Cell Line, Tumor; D005419:Flavonoids / Q000494:pharmacology*; D022781:Hepatocytes / Q000187:drug effects*; D006801:Humans; D009793:Ochratoxins / Q000037:antagonists & inhibitors* / Q000633:toxicity*; D010636:Phenols / Q000494:pharmacology*; D059808:Polyphenols; D013997:Time Factors; D024502:alpha-Tocopherol / Q000494:pharmacology*
D000975:Antioxidants; D005419:Flavonoids; D009793:Ochratoxins; D010636:Phenols; D059808:Polyphenols; C025589:ochratoxin A; D024502:alpha-Tocopherol