5,7-Dimethoxy-3-(2 '-hydroxybenzyl)-4-chromanone inhibits alpha-glucosidase in vitro and alleviates postprandial hyperglycemia in diabetic mice

摘要

This study was designed to investigate the inhibitory activities of 5,7-dimethoxy-3-(2'hydro-xybenzyl)-4-chromanone (5,7-D chromanone) isolated from Portulaca oleracea L. on carbohydrate digesting enzymes and its ability to improve postprandial hyperglycemia in streptozotocin-induced diabetic mice. 5,7-D chromanone strongly inhibited alpha-glucosidase and -amylase (half-maximal inhibitory concentration, IC50 ; 15.03 +/- 2.59 mu M and 12.39 +/- 2.16 mu M, respectively). The inhibitions were more effective than acarbose, which was the positive control. The increase in blood glucose level after ingesting starch was more significantly alleviated in the 5,7-D chromanone ingested group than in the control group of diabetic mice. In the control group, blood glucose levels were 24.64 +/- 1.73, 27.22 +/- 1.58, and 26.37 +/- 1.41 mM, and in the 5,7-D chromanone ingested group were 23.87 +/- 1.10, 23.38 +/- 1.32, and 21.42 +/- 1.36 mM at 30, 60, and 120 min, respectively. In addition, the area under the curve of blood glucose significantly declined with 5,7-D chromanone ingestion in diabetic mice. The results indicate that 5,7-D chromanone can help lower postprandial hyperglycemia by inhibiting carbohydrate digesting enzymes.