[Studies on anti-hyperglycemic effect and its mechanism of Clinopodium chinense]

To investigate the anti-hyperglycemic effect and its mechanism of ethanol extraction from Calamintha chinensis (EJCT).

Fasting serum glucose (FSG) in normal mice was determined after oral administration of EJCT. Effects of EJCT on hyperglycemia mice induced by adrenaline were investigated by observing the contents of FSG and liver glucogen. Effect of EJCT on the diabetic mice induced by alloxan was investigated by observing the contents of FSG and the injured degree of pancreatic islet. The antilipid-peroxidation of EJCT on liver homogenate was measured by determination of malondiadehyde (MDA) induced by Fe2+/Cys.

EJCT showed no obvious effect on FSG in normal mice. However, EJCT 300, 600 mg x kg(-1) could remarkably decrease the contents of FSG and increase liver glucogen in hyperglycemia mice induced by adrenaline. In diabetic mice induced by alloxan, EJCT 150, 300, 600 mg x kg(-1) could remarkably decrease the contents of FSG. The damage of pancreatic islet induced by alloxan was also significantly attenuated by EJCT. Furthermore, EJCT 30, 60, 90, 120 mg x L(-1) inhibited lipid peroxidation initiated by Fe2+/Cys in liver homogenate.

These results suggest that EJCT can significantly attenuate hyperglycemia in diabetic mice, which is probably due to decreasing the decomposition of liver glucogen, increasing the synthesis of liver glucogen, antioxidation and amelioration of damaged pancreatic islet.