Protects Effects of Fucoidan Against Renal Oxidative Stress in Aged Mice Fed with Low‐protein Diet

Abstract

Fucoidans are sulfated polysaccharides that are extracted from brown algae. Fucoidans with low molecular weight (LMWF) have been revealed various biological activities and health benefits. The aim of the study was to evaluate the effects of LMWF on renal markers of proinflammatory cytokines and antioxidant defense system in the kidney of aged mice fed with a low protein diet. Eighty-seven-week-old male C57BL/6J mice were fed a regular chow diet (CO, 23% protein), a low-protein (LO, 6.9% protein) diet, or a LO diet with fucoidan supplemented (300 mg/kg, 3 times/week, LO+F) diet for 13 weeks. The levels of renal IL-1β, IL-6 and TNF-α did not affect by the dietary protein proportion, while the fucoidan supplementation significantly decreased the production of TNF-α as compared to the CO group. When compared to the LO group, fucoidan supplementation significantly decreased the level of thiobarbituric acid reactive substances and increased glutathione (GSH) in the kidney. Besides, fucoidan supplementation had been shown to significantly recover the expression of antioxidant enzymes, including superoxide dismutase, glutathione peroxidase, catalase, glutathione reductase and heme oxygenase-1 in the kidney of aged mice fed with a low protein diet. In summary, the LMWF might protect against oxidative stress in the kidney of aged mice fed with low protein diet.