Antidiabetic Effect of an Active Components Group fromIlex kudingchaand Its Chemical Composition
The leaves ofIlex kudingchaare used as an ethnomedicine in the treatment of symptoms related with diabetes mellitus and obesity throughout the centuries in China. The present study investigated the antidiabetic activities of an active components group (ACG) obtained fromIlex kudingchain alloxan-induced type 2 diabetic mice. ACG significantly reduced the elevated levels of serum glycaemic and lipids in type 2 diabetic mice. 3-Hydroxy-3-methylglutaryl coenzyme A reductase and glucokinase were upregulated significantly, while fatty acid synthetase, glucose-6-phosphatase catalytic enzyme was downregulated in diabetic mice after treatment of ACG. These findings clearly provided evidences regarding the antidiabetic potentials of ACG fromIlex kudingcha. Using LC-DAD/HR-ESI-TOF-MS, six major components were identified in ACG. They are three dicaffeoylquinic acids that have been reported previously, and three new triterpenoid saponins, which were the first time to be identified inIlex kudingcha. It is reasonable to assume that antidiabetic activity ofIlex kudingchaagainst hyperglycemia resulted from these six major components. Also, synergistic effects among their compounds may exist in the antidiabetic activity ofIlex kudingcha.