Antioxidant Effects of Soy Isoflavones, Probiotics and Their Combination on Carbon Tetrachloride-Induced Oxidative Stress in Rats

Background and Objective: The health benefits of isoflavone consumption are often attributed to its antioxidant properties. Since the gut microbiome has a large impact on isoflavone metabolism, probiotics might enhance isoflavone bioavailability and in vivo antioxidant activity. The aim of this study was to assess the antioxidant effects of isoflavones, probiotics and their combination on Carbon Tetrachloride (CCl4)-induced oxidative stress in rats. Materials and Methods: Wistar rats were allocated to seven groups of six animals, group I: Control group received saline solution (1 mL/kg p.o.), II: Soy isoflavones (50 mg/kg p.o.), III: Probiotics (10(9) CFU/kg p.o.), IV: CCl4 (1 mg/kg i.p.) and V-VII: After CCl4, which was fed isoflavones, probiotics or their combination for 14 days, after which the animals were sacrificed. The antioxidative effects of isoflavones, probiotics and their combination were determined by biochemical parameters in serum, the oxidative stress parameters in liver and kidney homogenates and by histological assessment. Results: In comparison to those in the CCl4 treatment group, the functional markers of hepatotoxicity, particularly Alanine Aminotransferase (ALT) and Aspartate Aminotransferase (AST) activity, were significantly lower in the group treated with the combination of isoflavones and probiotics. This combination successfully reduced the CCl4-induced increase in malondialdehyde levels in liver tissue, while histopathological changes in hepatocytes, were notably attenuated. Conclusion: The results indicate that the combined consumption of isoflavones and probiotics inhibits the level of lipid peroxidation and has a hepatocurative effect on CCl4-induced oxidative stress in rats, significantly improving the functional and morphological parameters of the liver.