P12-38 Exploring the antioxidant and toxicological effects of grape stem and wine extracts: A comparative study in mice and rats

Wine and its by-products, such as grape stems, are rich sources of bioactive polyphenolic compounds with potential health benefits for both animals and humans. These compounds are known for their antioxidant and cytoprotective properties, which have attracted increasing interest for their role in disease prevention. Despite their promise, there is a lack of comprehensive in vivo studies assessing the safety and potential toxicological effects of polyphenols. The aim of this study was two-fold: To investigate the effects of oral administration of a grape stem extract derived from the Greek red wine Mavrodaphne on redox biomarkers in mice. To evaluate the biological effects of oral administration of a wine extract derived from the emblematic Greek red wine Xinomavro on rats. To explore the effects of these polyphenol-rich extracts, the study monitored the following parameters in both animal models: Body weight and growth rate, hematological and biochemical markers, histopathological analysis of key tissues, redox biomarkers indicative of oxidative stress and antioxidant defense Mice received the Mavrodaphne grape stem extract, while rats were administered the Xinomavro wine extract. Both extracts were given orally, and biological samples were collected and analyzed to determine systemic and tissue-specific responses. Mavrodaphne Grape Stem Extract (Mice): The extract improved redox homeostasis and protected against oxidative stress by significantly reducing lipid peroxidation. These effects suggest a strong antioxidant potential of the extract, with no observed adverse outcomes under the study conditions. Xinomavro Wine Extract (Rats): The extract produced both beneficial and adverse effects on redox status, depending on the tissue examined. This dual response highlights the complexity of polyphenol activity and the importance of context in evaluating their health impact. This study demonstrates that the Xinomavro wine extract had no impact on body weight, growth, or clinical parameters but affected redox balance in rats, showing both antioxidant and prooxidant effects depending on the tissue. This highlights the complexity of polyphenolic compounds, which do not act uniformly across biological systems. In contrast, the Mavrodaphne grape stem extract showed beneficial effects in mice by preventing lipid peroxidation and inducing redox adaptations in antioxidant defense mechanisms. These findings contribute to a growing body of research supporting the potential health applications of wine by-products while also underscoring the need for further investigation into their safety, efficacy, and mechanisms of action.