Lowering Effect Of Konjac Polysaccharide On Blood Lipid And Glucose Of Mice Treated With High Fat And Its Mechanism

Objective By adopting the method of mixing konjac polysaccharide with high fat to feed mice, observing the effect of konjac polysaccharide on body weight, blood lipids, blood glucose, serum leptin and Na~+-K~+-ATPase activity of mice treated with high fat, to investigate the lowering effect of konjac polysaccharide on blood lipids and blood glucose of mice and its mechanism.Methods Fifty SPF level Kunming female mice, weighing 20-22g, adaptivly fed in the laboratory for one week, were randomly divided into normal control, high-fat control, and high, middle, low dose of konjac polysaccharide combining high fat groups. There were ten mice in each group. The mice in normal control group were fed normal diet, those in high-fat control were fed high-fat diet, those in high, middle, low dose of konjac polysaccharide combining high fat groups were fed 0.8g/100g, 0.4g/100g, 0.2g/100g konjac polysaccharide. The mice were fed for twenty days. The levels of serum leptin were determined by ELISA methods, intestinal mucosa Na~+-K~+-ATPase activities were determined by uv-spectrophotometry, fasting and postprandial blood glucose were determined by glucometer, serum cholesterol content were determined by had cholesterol oxidase - enzymatic oxides methods. The body weight, adipose tissue, dry weight and wet weight of the fecal were all examined by electronic scale.Results At the 10th day of experiment, body weight and postprandial blood glucose of high-fat control group were 31.3±2.11g and 7.5±1.15mmol/L, those of high dose konjac polysaccharide combining high fat group were 28.0±2.06g and 4.8±0.73 mmol/L. At the 20th day, fasting blood glucose, serum cholesterol content, concentrations of serum leptin and Na~+-K~+-ATPase activities of high-fat control group were 5.8±1.31 mmol/L, 3.85±0.62mmol/L, 1078.5±61.69pg/ml and 16.2±1.48μmol Pi/(mg pro·h), those of high dose konjac polysaccharide combining high fat group were 4.7±1.21mmol/L, 2.32±0.44mmol/L, 820.5±58.52pg/ml and 11.2±1.10μmol Pi/(mg pro·h). By the method of one-way analysis of variance and q-test, the differences between two groups were significant (P<0.05).Conclusion Konjac polysaccharide could decrease the levels of body weight, postprandial blood glucose, serum cholesterol content, serum leptin and intestinal mucosa Na~+-K~+-ATPase activity of mice treated with high fat. The lowering effect of konjac polysaccharide on blood lipids and blood glucose of mice not only is relevant with its water-swelling, filling the gastrointestinal tract, having a sense of satiety and adhering nutrients, but also may inhibit intestinal absorption function by reducing intestinal mucosa Na~+-K~+-ATPase activity of mice, which results in the decline of postprandial blood glucose, body weight and adipose tissue, while the decline of body weight and adipose tissue feedback caused a lower level of serum leptin of mice.