Antihyperglycemic effects of total flavonoids from Polygonatum odoratum in STZ and alloxan-induced diabetic rats.
OBJECTIVE
Total flavonids of Polygonatum(P) odoratum (TFP) were tested for anti-diabetic activity in streptozotocin (STZ)-induced diabetic mice and alloxan-induced diabetic rats.


METHODS
Rhizoma Polygonati Odorati, well-known Chinese traditional medicine, is widely used for treatment of diverse diseases for example diabetes. In our study, TFP was extracted by 70% ethanol and purified by macroreticular resin. The experiments were designed to detect the anti-diabetic activity of TFP by determination of blood glucose (BG) using one touch gluco-meter and insulin levels by using a radioimmunoassay kit in streptozotocin (STZ)-induced diabetic mice and alloxan-induced diabetic rats and alpha-amylase inhibitory activity by alpha-amylase inhibition assay in vitro.


RESULTS
TFP had beneficial effects on regulation of blood glucose. Daily administration with 50-200 mg/kg body weight of TFP for 9 days can reduce significantly hyperglycemia in STZ-induced diabetic mice. Thirtieth day administration with TFP (50-200 mg/kg body weight) also decreased significantly fasting blood glucose in alloxan-induced diabetic rats. The hypoglycemic effect of TFP at 50 and 100 mg/kg is less than that of acarbose 20 mg/kg and gliclazide 15 mg/kg. The hypoglycemic effects of TFP at 200 mg/kg is similar to that of acarbose 20 mg/kg and gliclazide 15 mg/kg. TFP also could increase significantly the insulin level in alloxan-induced type 2 diabetic rats (P<0.05) compared with control. Alpha-amylase inhibition assay in vitro showed that TFP inhibited significantly alpha-amylase activity in a dose-dependent manner.


CONCLUSIONS
TFP possess significant dose-dependent anti-diabetic activity. TFP is one of the primary hypoglycemic active compounds of Polygonatum odoratum which would worth further study and development.
Shu
Xiao-Shun
XS
College of Biology & Chemistry Engineering, Changsha University of Science & Technology, Changsha 410076, PR China. sxs732@yahoo.com.cn
Lv
Jin-Hai
JH
Tao
Jun
J
Li
Guo-Ming
GM
Li
Huai-Den
HD
Ma
Ning
N
D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy*; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000188:drug therapy; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000188:drug therapy; D004032:Diet; D004041:Dietary Fats / Q000009:adverse effects; D005419:Flavonoids / Q000494:pharmacology*; D005951:Glucose Tolerance Test; D007004:Hypoglycemic Agents; D007328:Insulin / Q000097:blood; D051379:Mice; D018517:Plant Roots / Q000737:chemistry; D031384:Polygonatum / Q000737:chemistry*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012015:Reference Standards; D000516:alpha-Amylases / Q000037:antagonists & inhibitors
D004041:Dietary Fats; D005419:Flavonoids; D007004:Hypoglycemic Agents; D007328:Insulin; D000516:alpha-Amylases