Inhibitory effects of chondroitin sulfate prepared from salmon nasal cartilage on fat storage in mice fed a high-fat diet

OBJECTIVE: Chondroitin sulfate is an acidic polymer consisting of repeating D-glucuronic acid and D-N-acetylgalactosamine units, and the N-acetylgalac tosamine is substituted with the sulfate at either the 4 or 6 position, wit h approximately one sulfate being present per disaccharide unit. The presen t study assessed the effects of chondroitin sulfate on the activity of panc reatic lipase and lipid uptake into brush border membrane vesicles of the r at small intestine in vitro, and on the degree of fat storage induced in mi ce by the oral administration of a high-fat diet for 8 weeks. DESIGN AND MEASUREMENTS: Experiments were carried out to clarify whether or not chondroitin sulfate inhibited pancreatic lipase activity in assay syst ems using triolein emulsified with phosphatidylcholine or gum arabic. In ad dition, the effects of chondroitin sulfate on lipid absorption by brush bor der membrane vesicles were examined. Moreover, mice were fed a high-fat die t and treated with chondroitin sulfate for 8 weeks. RESULTS: Chondroitin sulfate dose-dependently inhibited the pancreatic lipa se activity in an assay system using triolein emulsified with phosphatidylc holine. In addition, chondroitin sulfate inhibited the palmitic acid uptake into the brush border membrane vesicles of the rat jejunum. Chondroitin su lfate caused the reduction of body weight and parametrial adipose tissue we ight, and prevention of fatty liver and hyperlipidemia in mice fed a high-f at diet. CONCLUSION: The reduction of fat storage and the antihyperlipidemic action of chondroitin sulfate might be due to the inhibition of small intestinal a bsorption of dietary fat through the inhibition of pancreatic lipase activi ty and fatty acid uptake through brush border membrane.