Insulin like activity in (-) epicatechin.

Water extract of the bark of plant ofPterocarpus marsupium Roxb is used as an antidiabetic drug in indigenous medicine in India. (−) Epicatechin, its active principle, has been found to be insulinogenic. The presentin vitro study reports some insulin like activities of (−) epicatechin. Like insulin, (−) epicatechin stimulates oxygen uptake in fat cells and tissue slices of various organs, increases glycogen content of rat diaphragm in dose-dependent manner with corresponding increase in U14-C glucose uptake, and inhibits theophylline induced lipolysis in isolated fat pads in dose-dependent manner. Experiments on competitive binding of125I-insulin and (−) epicatechin to liver cell plasma membrane indicate that insulin does not share binding site with (−) epicatechin. (−) Epicatechin at a concentration of up to 1 mM does not effect the release of glucagon from the isletsin vitro. Thus, (−) epicatechin has insulinogenic as well as insulin like properties.