SOD1 and liver dysplastic nodule: 44 Studies have shown that MDA increases and SOD decreases in STZ-induced DN.45,46 SOD is the first barrier to free radical oxidative damage, which is to remove free radicals.47 In addition, MDA is the end-product of lipid peroxidation, indicating the degree of oxidative damage.48 The antioxidant capacity of T-AOC directly reflects the ability of the body to remove free radicals.49 Thus, our study indicates that these oxidative stress markers demonstrate the antioxidative potential of SPP treatment in a high-fat diet and STZ-induced diabetic mice.