title: Combined effects of high-fat diet and ethanol induce oxidative stress in rat liver.
abstract: Individuals affected by liver steatosis seldom have symptoms of liver injury, but may be particularly vulnerable to oxidative insults. In this study, we evaluated liver redox alterations produced by acute ethanol administration to rats that were fed a high-fat diet (HFD). Adult male Wistar rats were fed HFD or standard diet (controls) for 1 month; a group of animals from each condition were gavaged with 35% (vol/vol) ethanol every 12h for the last 3 days of the experiment. Total lipid content determined in liver showed lipid accumulation after HFD or HFD combined with ethanol. HFD alone induced a significant rise of seric alanine aminotransferase levels and a marked reduction of antioxidant enzyme activities (catalase, superoxide dismutase, glutathione transferase). Ethanol alone caused a significant rise of seric cholesterol levels and enhanced mitochondrial H2O2 production, but without apparent oxidative stress as evaluated by thiobarbituric acid-reactive substances (TBARS) assay. The combination of HFD and acute ethanol caused an increase of TBARS, indicating lipid peroxidation, most likely as a consequence of a decrease in antioxidant defenses induced by HFD and of an increase in reactive oxygen species production induced by ethanol. Principal component analysis, based on all the measured parameters, that is, serum liver function tests, antioxidant enzyme activities, mitochondrial H2O2 release, and TBARS, indicated that HFD and ethanol act as two independent factors. In conclusion, our results show that HFD or acute ethanol alone produce, at the most, mild liver injury, whereas their combination triggers oxidative stress, possibly inducing a progression toward liver disease. Hence, our data indicate that a diet too rich in fat is a serious risk factor for the occurrence of liver injury deriving from acute ethanol consumption.
authors.affiliation: Dipartimento di Biologia, Università di Genova, Corso Europa 26, I-16132 Genova, Italy. idemori@unige.it
authors.forename: Ilaria
authors.initials: I
authors.lastname: Demori
authors.forename: Adriana
authors.initials: A
authors.lastname: Voci
authors.forename: Emilia
authors.initials: E
authors.lastname: Fugassa
authors.forename: Bruno
authors.initials: B
authors.lastname: Burlando
mesh_terms: D000410:Alanine Transaminase / Q000097:blood; D000818:Animals; D002374:Catalase / Q000378:metabolism; D002492:Central Nervous System Depressants / Q000008:administration & dosage* / Q000009:adverse effects*; D056486:Chemical and Drug Induced Liver Injury; D002784:Cholesterol / Q000097:blood; D004041:Dietary Fats / Q000008:administration & dosage* / Q000009:adverse effects*; D004334:Drug Administration Schedule; D000431:Ethanol / Q000008:administration & dosage* / Q000009:adverse effects*; D005982:Glutathione Transferase / Q000378:metabolism; D007441:Intubation, Gastrointestinal; D015227:Lipid Peroxidation / Q000187:drug effects; D008099:Liver / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D008297:Male; D010084:Oxidation-Reduction; D018384:Oxidative Stress / Q000187:drug effects*; D025341:Principal Component Analysis; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism; D012307:Risk Factors; D013482:Superoxide Dismutase / Q000378:metabolism; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism; D014280:Triglycerides / Q000097:blood
chemical_list: D002492:Central Nervous System Depressants; D004041:Dietary Fats; D017382:Reactive Oxygen Species; D017392:Thiobarbituric Acid Reactive Substances; D014280:Triglycerides; D000431:Ethanol; D002784:Cholesterol; D002374:Catalase; D013482:Superoxide Dismutase; D005982:Glutathione Transferase; D000410:Alanine Transaminase