A Polyphenol-rich plant extract reduces oxidative stress in the gastrocnemius muscle of mice with high-fat high-sucrose diet-induced obesity

Abstract Age-related diseases linked to obesity are often associated with significant oxidative stress. In this context, the antioxidant properties of a polyphenol-rich plant extract (PRPE) were evaluated using complementary biochemical assays and in vivo in the skeletal gastrocnemius muscle of mice treated with PRPE and subjected to different diets, i.e., standard diet (Std) or high-fat/high-sucrose diet (HFHS). We report that PRPE is a potent antioxidant mixture, as shown by its Reactive Oxygen Species (ROS) scavenging properties by using different assays: KRL (biological-based Kit Radicaux Libres, i.e., Free Radicals Kit) and chemical-based assays: DPPH, FRAP, and TEAC. We observe an antioxidant effect in the gastrocnemius muscle from mice under a high-sucrose diet (HFHS) treated with PRPE: increased antioxidant activities revealed with the KRL assay (expressed in Trolox equivalent), and stimulated expression of genes involved in oxidative stress defense under ROS exposure by RT-qPCR: Nuclear Respiratory Factor 1 (Nrf1), Sirtuin1 (Sirt1), Superoxide Dismutase 1 (Sod1); Uncoupling protein 2 (Ucp2). These in vivo data, which were lacking until now, are in agreement with earlier results of the in vitro approach reporting significant protective activities of PRPE on the C2C12 skeletal muscle cell line. They confirm the efficacy of the PRPE in the diet of treated animals, especially in skeletal muscle.