Skate cartilage extracts containing chondroitin sulfate ameliorates hyperlipidemia-induced inflammation and oxidative stress in high cholesterol diet-fed LDL receptor knockout mice in comparison with shark chondroitin sulfate

BACKGROUND/OBJECTIVES: In this study, we investigated the beneficial effects of skate cartilage extracts containing chondroitin sulfate (SCS) on hyperlipidemia-induced inflammation and oxidative stress in high cholesterol diet (HCD)-fed mice in comparison with the effects of shark cartilage-derived chondroitin sulfate (CS). MATERIALS/METHODS: Low-density lipoprotein receptor knockout (LDLR-KO) mice were fed HCD with an oral administration of CS (50 and 100 mg/kg BW/day), SCS (100 and 200 mg/kg BW/day), or water, respectively, for ten weeks. RESULTS: The administration of CS or SCS reduced the levels of serum triglyceride (TG), total cholesterol (TC), and LDL cholesterol and elevated the levels of high-density lipoprotein cholesterol, compared with those of the control group (P < 0.05). Furthermore, CS or SCS significantly attenuated inflammation by reducing the serum levels of interleukin (IL)-1β and hepatic protein expression levels of nuclear factor kappa B, inducible nitric oxide synthase, cyclooxygenase-2, and IL-1beta (P < 0.05). In particular, the serum level of tumor necrosis factor-alpha was reduced only in the 100 mg/kg BW/day of SCS-fed group, whereas the IL-6 level was reduced in the 100 and 200 mg/kg BW/day of SCS-fed groups (P < 0.05). In addition, lipid peroxidation and nitric oxide production were attenuated in the livers of the CS and SCS groups mediated by the upregulation of hepatic proteins of antioxidant enzymes, such as superoxide dismutase, catalase, and glutathione peroxidase (P < 0.05). CONCLUSIONS: These results suggest that the biological effects of SCS, similar to those of CS, are attributed to improved lipid profiles as well as suppressed inflammation and oxidative stress induced by the intake of HCD.