Hypoglycemic constituents of Panax ginseng.

This article reviews the recent progress in the identification of hypoglycemic and insulino-mimetic principles in ginseng. Hitherto five types of substances have been discovered. They include five glycans designated panaxans A to E, adenosine, a carboxylic acid, a peptide with a molecular weight of 1400 and lacking in basic amino acid residues, and a fraction designated DPG-3-2 prepared from the water extract of ginseng. The structure of panaxan A has been partially elucidated and the glycans have been demonstrated to elicit hypoglycemia in both normal and diabetic mice. DPG-3-2 exerted its hypoglycemic action or provoked insulin secretion in diabetic and glucose-loaded normal mice while having no effect on normal mice. Adenosine, the carboxylic acid and the mol. wt 1400 peptide inhibited catecholamine-induced lipolysis in rat epididymal fat pads. EPG-3-2, a fraction related to DPG-3-2, also exhibited antilipolytic activity.