Cloudy apple juice protects against chemical-induced oxidative stress in rat.

Background: Apples abundant in phenolic compounds show a variety of biological activities that may contribute to beneficial effects against some chronic diseases. Purpose: The aim of our study was to assess the protective effect of cloudy apple juice against chemical-induced oxidative stress in rats. Methods: Male Wistar rats were treated with apple juice per os, 10 mL/kg/day for 28 days and with a single dose of N-nitrosodiethylamine (NDEA), 150 mg/kg or carbon tetrachloride (CCl), 2 mL/kg, 24 h before killing. Two groups of rats not pretreated with juice were administered each of the xenobiotics alone. Results: Microsomal lipid peroxidation in the liver was decreased in rats pretreated with juice by 52-87% when compared to animals given NDEA or CCl alone. Pretreatment with juice protected antioxidant enzymes: catalase, glutathione peroxidase and glutathione reductase but not superoxide dismutase. Their activity was recovered by 49-173% when compared to that in rats given either toxicant alone. The plasma activity of paraoxonase1 was reduced by both toxicants and was increased by 23% in the apple/CCl group. A rise in plasma protein carbonyls caused by the xenobiotics was reduced by 20% only in apple/NDEA-treated rats. Also, in this group of animals, a 9% decrease in DNA damage in blood leukocytes was observed. Conclusion: Phytochemicals in commonly consumed apple juice may protect some macromolecules against oxidative insult induced by xenobiotics. [ABSTRACT FROM AUTHOR]