## 4 Discussion
[56] showed that in the liver of adult male rats receiving 5 g of ethanol per kg of body weight at the concentration of 20% for 60 days, significantly higher TBARS level was observed than that found in the control group. This results from the fact that ethanol intake causes oxidative stress mainly due to increased production of oxygen free radicals and reduced antioxidant level in cells [64]. [PERSON] et al. [65] revealed also that recurring episodes of alcohol intoxication in the period of maturation enhance liver lipid peroxidation process in growing female rats. The present study revealed a positive association between red wine intake as well as intake of phenolic acids or anthocyanins and the TBARS level in the liver of growing male rats. To date, there is not enough studies on the influence of specific polyphenols of red wine on the oxidative stress parameters in the liver in growing organisms to be able to explain the results observed in the presented own study. Several studies conducted in humans and laboratory animals indicate the positive action of specific phenolic acids and anthocyanins on oxidative stress parameters, especially on lipid peroxidation. [PERSON] et al. [66] noted that cyanidin 3-glucoside, ferulic acid, and p-coumaric acid significantly reduced lipid peroxidation in erythrocytes of patients with hypercholesterolemia; hence, it was concluded that these compounds are characterized by important antioxidative properties. Similarly, [PERSON] et al. [67] showed normalization of the TBARS level in the liver of diabetic mice after 45 days of oral supplementation of ferulic acid. [PERSON] et al. [68] also revealed that p-coumaric acid is an important antioxidant that increases total antioxidant capacity and reduces lipid peroxidation in the liver of hyperlipidemic mice. At the same time, [PERSON] et al. [69] noted a positive effect of sinapic acid on oxidative stress in the heart tissues of diabetic rats, while [PERSON] et al. [70] revealed that sinapic acid applied in case of high-fat diet reduced ROS and malondialdehydedehyde levels in the colon, while increasing the total antioxidant capacity in the liver of rats. [PERSON] et al. [71] also observed reduced liver TBARS level in rats receiving high doses of iron and caffe acid for four weeks, and the authors emphasized its high bioavailability. Similarly, [PERSON] et al. [72] observed a negative association between hydroxybenzoic acid intake and TBARS blood level. Furthermore, [PERSON] et al. [73] proved that cyanidin 3-glucose was a powerful antioxidant and reduced oxidative damage in rat liver. From the abovementioned studies, it could be summarized that various phenolic acids or anthocyanins reduce lipid oxidation, which results from oxidative stress, in various tissues. Some other studies have assessed the influence of red wine and its polyphenols on oxidative stress parameters. [PERSON] et al. [74] revealed that in a group of men consuming moderate amount of red wine for 28 days, there was a significantly lower level of malondialdehydedehyde--a marker of lipid peroxidation--than in those consuming gin; this finding was attributed to the influence of red wine polyphenols. Similarly, [PERSON] et al. [75] observed reduced level of lipid peroxidation products in blood of adult rats after four weeks of consumption of a diet supplemented with red wine solution or lyophilisate. However, the authors did not reveal any differences between the studied groups receiving red wine solution and lyophilisate, which was thought to be associated with a low concentration of ethanol and a high content of polyphenols received by both groups [75]. [PERSON] et al. [76] and [PERSON] et al. [77] demonstrated that red wine may prevent hyperglycemia-induced lipid peroxidation, but the effect was observed only for low doses of red wine.