TY - JOUR
T1 - Green tea polyphenol epigallocatechin-3-gallate protects HepG2 cells against CYP2E1-dependent toxicity
AU - Jimenez-Lopez, Jose M.
AU - Cederbaum, Arthur I.
N1 - Funding Information:
This study was supported by U.S. Public Health Services Grants AA03312 and AA06610 from the National Institute on Alcohol Abuse and Alcoholism.
PY - 2004/2/1
Y1 - 2004/2/1
N2 - Chronic ethanol consumption causes oxidative damage in the liver, and induction of cytochrome P450 2E1 (CYP2E1) is one pathway involved in oxidative stress produced by ethanol. The hepatic accumulation of iron and polyunsaturated fatty acids significantly contributes to ethanol hepatotoxicity in the intragastric infusion model of ethanol treatment. The objective of this study was to analyze the effect of the green tea flavanol epigallocatechin-3- gallate (EGCG), which has been shown to prevent alcohol-induced liver damage, on CYP2E1-mediated toxicity in HepG2 cells overexpressing CYP2E1 (E47 cells). Treatment of E47 cells with arachidonic acid plus iron (AA + Fe) was previously reported to produce synergistic toxicity in E47 cells by a mechanism dependent on CYP2E1 activity and involving oxidative stress and lipid peroxidation. EGCG protected E47 cells against toxicity and loss of viability induced by AA+Fe; EGCG had no effect on CYP2E1 activity. Prevention of this toxicity was associated with a reduction in oxidative damage as reflected by decreased generation of reactive oxygen species, a decrease in lipid peroxidation, and maintenance of intracellular glutathione in cells challenged by AA+Fe in the presence of EGCG. AA+Fe treatment caused a decline in the mitochondrial membrane potential, which was also blocked by EGCG. In conclusion, EGCG exerts a protective action on CYP2E1-dependent oxidative stress and toxicity that may contribute to preventing alcohol-induced liver injury, and may be useful in preventing toxicity by various hepatotoxins activated by CYP2E1 to reactive intermediates.
AB - Chronic ethanol consumption causes oxidative damage in the liver, and induction of cytochrome P450 2E1 (CYP2E1) is one pathway involved in oxidative stress produced by ethanol. The hepatic accumulation of iron and polyunsaturated fatty acids significantly contributes to ethanol hepatotoxicity in the intragastric infusion model of ethanol treatment. The objective of this study was to analyze the effect of the green tea flavanol epigallocatechin-3- gallate (EGCG), which has been shown to prevent alcohol-induced liver damage, on CYP2E1-mediated toxicity in HepG2 cells overexpressing CYP2E1 (E47 cells). Treatment of E47 cells with arachidonic acid plus iron (AA + Fe) was previously reported to produce synergistic toxicity in E47 cells by a mechanism dependent on CYP2E1 activity and involving oxidative stress and lipid peroxidation. EGCG protected E47 cells against toxicity and loss of viability induced by AA+Fe; EGCG had no effect on CYP2E1 activity. Prevention of this toxicity was associated with a reduction in oxidative damage as reflected by decreased generation of reactive oxygen species, a decrease in lipid peroxidation, and maintenance of intracellular glutathione in cells challenged by AA+Fe in the presence of EGCG. AA+Fe treatment caused a decline in the mitochondrial membrane potential, which was also blocked by EGCG. In conclusion, EGCG exerts a protective action on CYP2E1-dependent oxidative stress and toxicity that may contribute to preventing alcohol-induced liver injury, and may be useful in preventing toxicity by various hepatotoxins activated by CYP2E1 to reactive intermediates.
KW - Arachidonic acid
KW - CYP2E1
KW - Epigallocatechin-3-gallate
KW - Free radicals
KW - HepG2 cells
KW - Iron
KW - Oxidative stress
UR - https://www.scopus.com/pages/publications/1642440239
U2 - 10.1016/j.freeradbiomed.2003.11.016
DO - 10.1016/j.freeradbiomed.2003.11.016
M3 - Article
C2 - 15036355
AN - SCOPUS:1642440239
SN - 0891-5849
VL - 36
SP - 359
EP - 370
JO - Free Radical Biology and Medicine
JF - Free Radical Biology and Medicine
IS - 3
ER -