Abstract
Panax quinquefolium L. (Araliaceae), which grows in the United States and Canada, is known as American ginseng, and is commonly used as herbal medicine in the United States. The heat-processing method to strengthen the efficacy of Panax ginseng has been well defined in Korea based on the long history of ethnopharmacological evidence. It is possible, therefore, that the efficacy of American ginseng may also increase by heat-processing as in Panax ginseng, and this was experimentally studied by us. Based upon chemical and biological activity tests, the scientific evidence underlying the therapeutic potential of heat-processed American ginseng against oxidative stress and related tissue damage was elucidated. The free radical-scavenging active components such as less-polar ginsenosides and Maillard reaction products in American ginseng were significantly increased in a heat-processing temperature-dependent manner, as in Panax ginseng. From animal experiments related to oxidative tissue damage, heat-processed American ginseng showed a renoprotective effect by ameliorating renal dysfunction and reducing elevated nuclear factor-kappa B, Nε e-(carboxymethyl)lysine, and receptor for advanced glycation endproducts protein expressions in the diabetic rat kidney. This investigation of specified bioactive constituents is important for the development of scientific ginseng-derived drugs from ethnomedicine. The results of the present study call for further testing involving human subjects to clarify the efficacy of dietary heat-processed American ginseng supplementation in diabetics.
