Protective effects of purple grape juice on carbon tetrachloride-induced oxidative stress in brains of adult Wistar rats

The antioxidant properties of purple grape juice, organic and conventional, in brain tissues are not well known. In this study our objective was to evaluate the antioxidant activity in substantia nigra and striatum of rats chronically treated with organic or conventional purple grape juice and to correlate the results obtained with the polyphenol content (total polyphenolic content, resveratrol, and anthocyanins [malvidin, delphinidin, peonidin, and cyanidin]). We observed that CCl4 damage decreased significantly in the grape juice-treated groups when compared with the control group. In the grape juice-treated groups we further observed a decrease of lipid (thiobarbituric acid-reactive substances assay) and protein (carbonyl) peroxidation, as well as a significant antioxidant protection through the increase of enzyme activity. Antioxidant activities were significantly correlated with polyphenol content. These findings demonstrated that both grape juices have potent antioxidant properties and these activities could be at least attributed to the high phenolic content present in these juices.