Ochratoxin a lowers mRNA levels of genes encoding for key proteins of liver cell metabolism.

Ochratoxin A (OTA) is a nephro- and hepatotoxic mycotoxin that frequently contaminates food and feedstuffs. Although recent studies have indicated that OTA modulates renal gene expression, little is known regarding its impact on differential gene expression in the liver. Therefore a microarray study of the HepG2 liver cell transcriptome in response to OTA exposure (0, 0.

Effect of Vitamin E on Cytochrome P450 mRNA Levels in Cultured Hepatocytes (HepG2) and in Rat Liver.

Vitamin E has been described in the literature as a regulator of gene expression. The gene-regulatory activity of vitamin E with regard to genes encoding cytochrome P450 (CYP) enzymes, which play a pivotal role both in the metabolism of xenobiotics and vitamin E, has not been conclusively characterised. The objective of the current study was, therefore, to elucidate the short- and long-term effects of natural and synthetic vitamin E on CYP gene expression using Affymetrix GeneChip® technology.

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.