title: Mechanistic studies on the antidiabetic activity of a polysaccharide-rich extract of Radix Ophiopogonis.
abstract: To study the hypoglycemic mechanisms of a polysaccharide-rich extract of Radix Ophiopogonis, the influences of the extract on activity of NIT-1 insulinoma cells damaged by streptozotocin (STZ), activity of α-glucosidase, glucose absorption into intestinal brush border membrane vesicles, gluconeogenesis by H4IIE hepatoma cells and glucose uptake by 3T3-L1 adipocytes were investigated. The results show that the extract improved the activity of NIT-1 cells damaged by STZ, inhibited glucose absorption into intestinal brush border membrane vesicles and reduced the activity of α-glucosidase. However, gluconeogenesis in H4IIE cells and glucose uptake in 3T3-L1 adipocytes did not change significantly in the presence of the extract. These results suggest that the hypoglycemic mechanisms of the polysaccharide-rich extract of Radix Ophiopogonis are caused by protection in pancreatic islet cells and the inhibition of carbohydrate digestion and absorption. This is possibly the first report on the underlying mechanisms responsible for the antidiabetic effect of Radix Ophiopogonis.
authors.affiliation: School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, PR China.
authors.forename: Linwei
authors.initials: L
authors.lastname: Ding
authors.forename: Peibo
authors.initials: P
authors.lastname: Li
authors.forename: Clara Bik San
authors.initials: CB
authors.lastname: Lau
authors.forename: Yuet Wa
authors.initials: YW
authors.lastname: Chan
authors.forename: Dingzhou
authors.initials: D
authors.lastname: Xu
authors.forename: Kwok-Pui
authors.initials: KP
authors.lastname: Fung
authors.forename: Weiwei
authors.initials: W
authors.lastname: Su
mesh_terms: D041721:3T3-L1 Cells; D017667:Adipocytes / Q000187:drug effects / Q000378:metabolism; D000818:Animals; D050260:Carbohydrate Metabolism / Q000187:drug effects*; D006528:Carcinoma, Hepatocellular; D045744:Cell Line, Tumor; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy / Q000378:metabolism; D005943:Gluconeogenesis / Q000187:drug effects; D005947:Glucose / Q000378:metabolism*; D065089:Glycoside Hydrolase Inhibitors; D007004:Hypoglycemic Agents / Q000494:pharmacology* / Q000627:therapeutic use; D050417:Insulin-Secreting Cells / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D007340:Insulinoma; D007413:Intestinal Mucosa / Q000187:drug effects; D019668:Liliaceae / Q000737:chemistry*; D051379:Mice; D008871:Microvilli / Q000187:drug effects; D010190:Pancreatic Neoplasms; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology* / Q000627:therapeutic use; D018517:Plant Roots; D011134:Polysaccharides / Q000494:pharmacology* / Q000627:therapeutic use; D011817:Rabbits; D051381:Rats
chemical_list: D065089:Glycoside Hydrolase Inhibitors; D007004:Hypoglycemic Agents; D010936:Plant Extracts; D011134:Polysaccharides; D005947:Glucose