A steroidal glycoside from Polygonatum odoratum (Mill.) Druce. improves insulin resistance but does not alter insulin secretion in 90% pancreatectomized rats.
The aim of this study was to investigate the effects of three steroidal glycosides (SG-100, SG-280, and SG-460) obtained from Polygonatum odoratum (Mill.) Druce. on insulin secretion, insulin action, and relative glucose uptake in various tissues of 90% pancreatectomized male Sprague-Dawley rats. One of the compounds (30 mg/kg body weight daily) with a 40%-fat diet was orally administered to a group of such rats for 13 weeks. On the day after a hyperglycemic clamp, euglycemic hyperinsulinemic clamp with 1 microCi of [1-(14)C]2-deoxyglucose per 100 g body weight was used. Serum glucose levels were lowest in the rats receiving SG-100. Insulin secretion from pancreatic beta-cells did not change with SG administration. Whole-body glucose disposal rates increased with SG-100 administration by 39%. SG-100 increased the glycogen contents and glycogen synthase activity in the soleus muscle of pancreatectomized rats. Uptake of [1-(14)C]2-deoxyglucose into the soleus muscle was higher in such rats receiving SG-100 than in rats receiving other compounds. In conclusion, SG-100 has an antihyperglycemic effect by promoting peripheral insulin sensitivity without changing insulin secretion.
Choi
Soo Bong
SB
Department of Internal Medicine, Konkuk University, Kyohyun-Dong, Chungioo-Si, Chungbuk-Do, Korea.
Park
Sunmin
S
D000818:Animals; D000963:Antimetabolites / Q000378:metabolism; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D003847:Deoxyglucose / Q000378:metabolism; D004435:Eating / Q000187:drug effects; D005947:Glucose / Q000378:metabolism; D015309:Glucose Clamp Technique; D006006:Glycogen Synthase / Q000378:metabolism; D006027:Glycosides / Q000302:isolation & purification / Q000494:pharmacology*; D006946:Hyperinsulinism / Q000097:blood; D007004:Hypoglycemic Agents / Q000302:isolation & purification / Q000494:pharmacology*; D007328:Insulin / Q000378:metabolism*; D007333:Insulin Resistance / Q000502:physiology*; D008112:Liver Glycogen / Q000378:metabolism; D008297:Male; D018482:Muscle, Skeletal / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D010180:Pancreatectomy; D010936:Plant Extracts / Q000494:pharmacology; D031384:Polygonatum / Q000737:chemistry*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013256:Steroids / Q000302:isolation & purification / Q000494:pharmacology*
D000963:Antimetabolites; D001786:Blood Glucose; D006027:Glycosides; D007004:Hypoglycemic Agents; D007328:Insulin; D008112:Liver Glycogen; D010936:Plant Extracts; D013256:Steroids; D003847:Deoxyglucose; D006006:Glycogen Synthase; D005947:Glucose