Abstract
Obesity is defined as abnormal deposition of triglyceride in fat cells, due to acceleration of lipogenesis in fat cells relative to the rate of lipolysis. Although both glucose and lipoproteins in blood are used as materials for lipogenesis in fat cells, lipoproteins (chylomicron and VLDL) are more suitable materials than glucose because fat cells are able to incorporate lipoprotein-derived fatty acids without hormonal control. Thus it seems possible that reduction of serum chylomicron might help to protect against obesity caused by a high-fat diet. It was found that chondroitin sulfate, chitin chitosan and/or lactosucrose was decreased in serum chylomicron. Intestinal absorption of dietary fat was reduced by a decrease in hydrolysis of dietary fat due to the inhibitory actions of chondroitin sulfate and chitin chitosan on pancreatic lipase activity, by inhibition of fatty acid absorption due to chondroitin sulfate, and by inhibition of 2-monoglyceride absorption due to lactosucrose. All these functional substances were found to prevent the increases in adipose tissue weight and liver triglyceride level in mice with obesity caused by a high-fat diet.
