Insulin releasing and alpha-glucosidase inhibitory activity of ethyl acetate fraction of Acorus calamus in vitro and in vivo.
BACKGROUND
The radix of Acorus calamus L. (AC) is widely used in the therapy of diabetes in traditional folk medicine of America and Indonesia, and we previously reported the insulin sensitizing activity of the ethyl acetate fraction of AC (ACE).


OBJECTIVE
To investigate the insulin releasing and alpha-glucosidase inhibitory activity of ACE in vitro and in vivo.


METHODS
Insulin releasing and alpha-glucosidase inhibitory effects of different fractions from AC were detected in vitro using HIT-T15 cell line and alpha-glucosidase enzyme. Furthermore, effects of ACE orally on serum glucose were detected in fasted and glucose/amylum challenged normal mice.


RESULTS
AC and ACE increased insulin secretion in HIT-T15 cells as gliclazide did. As in vivo results, ACE (400 and 800 mg/kg) significantly decreased fasting serum glucose, and suppressed the increase of blood glucose levels after 2g/kg glucose loading in normal mice. In addition, ACE as a mixed-type inhibitor inhibited alpha-glucosidase activity in vitro with an IC(50) of 0.41 microg/ml, and 100mg/kg of it clearly reduced the increase of blood glucose levels after 5 g/kg amylum loading in normal mice.


CONCLUSIONS
Apart from its insulin sensitizing effect, ACE may have hypoglycemic effects via mechanisms of insulin releasing and alpha-glucosidase inhibition, and thus improves postprandial hyperglycemia and cardiovascular complications.
Si
Mei-mei
MM
Institute of Pharmacology & Toxicology and Biochemical Pharmaceutics, College of Pharmaceutical Sciences, Zhejiang University, 388 Yu-hang-tang Road, Hangzhou, China.
Lou
Jian-shu
JS
Zhou
Chang-Xin
CX
Shen
Juan-Na
JN
Wu
Hong-Hai
HH
Yang
Bo
B
He
Qiao-Jun
QJ
Wu
Hao-Shu
HS
D000085:Acetates / Q000737:chemistry*; D029023:Acorus / Q000737:chemistry*; D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D002460:Cell Line; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D065089:Glycoside Hydrolase Inhibitors; D066298:In Vitro Techniques; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007700:Kinetics; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D019518:Postprandial Period
D000085:Acetates; D001786:Blood Glucose; D004791:Enzyme Inhibitors; D065089:Glycoside Hydrolase Inhibitors; D007328:Insulin; C007650:ethyl acetate