Green tea modulation of the biochemical and electric properties of rat liver cells that were affected by ethanol and aging.
The oxidative stress induced by chronic ethanol consumption, particularly in concert with the aging process, has been implicated in changes in the structure and functions of liver cell components including membrane phospholipids. To counteract such changes, particularly those resulting from lipid peroxidation, antioxidants may be applied. Green tea contains large amounts of polyphenols, mainly catechins, which possess antioxidant properties. The aim of this study was to estimate the efficacy of green tea's influence on the physicochemical and biochemical properties of the rat liver as affected by the aging process and/or chronic ethanol intoxication. Several methods were used to evaluate this effect. Antioxidant properties were evaluated by vitamin E and antioxidant status determination. The liver trigliceride and cholesterol levels were also estimated. The extent of lipid peroxidation was determined by measuring the level of lipid peroxidation products as thiobarbituric reactive substances (TBARS). The surface charge density of the rat liver cells was measured using electrophoresis. The concentration of the marker enzymes of liver damage (alanine aminotransferase and aspartate aminotransferase) in the blood serum was also evaluated. Relative to the controls, aging was found to cause a decrease in the liver's antioxidant abilities and provoke an increase in the level of lipid peroxidation; it also increased the surface charge density of the rat liver cell membrane. Ethanol significantly aggravated these changes. This might have resulted in the liver cell membrane damage visible as a leak of alanine aminotransferase and aspartate aminotransferase into the blood. The ingestion of green tea with ethanol partially prevented these aging and/or ethanol-induced changes. Long-term drinking of green tea partially prevents the changes in the structure and function of the cell membrane caused by chronic ethanol intoxication.
Dobrzyńska
Izabela
I
Institute of Chemistry, University of Białystok, Al. Piłsudskiego 11/4, 15-443 Białystok, Poland.
Sniecińska
Anna
A
Skrzydlewska
Elzbieta
E
Figaszewski
Zbigniew
Z
D000375:Aging / Q000378:metabolism; D000410:Alanine Transaminase / Q000032:analysis; D000437:Alcoholism / Q000517:prevention & control*; D000818:Animals; D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology*; D001219:Aspartate Aminotransferases / Q000032:analysis; D028241:Camellia sinensis / Q000737:chemistry*; D002462:Cell Membrane / Q000737:chemistry / Q000187:drug effects; D004563:Electrochemistry; D000431:Ethanol / Q000037:antagonists & inhibitors* / Q000633:toxicity; D022781:Hepatocytes / Q000737:chemistry / Q000187:drug effects* / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008297:Male; D018384:Oxidative Stress / Q000187:drug effects; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D013662:Tea / Q000737:chemistry*; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis; D014810:Vitamin E / Q000032:analysis / Q000378:metabolism
D000975:Antioxidants; D010936:Plant Extracts; D013662:Tea; D017392:Thiobarbituric Acid Reactive Substances; D014810:Vitamin E; D000431:Ethanol; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase