Ginsenosides and their metabolites: a review of their pharmacological activities in the skin.

Ginsenosides are representative pharmaceutical compounds found in various forms in Panax ginseng, a traditional medicinal plant. They are converted to their metabolites Rg2, Rg3, compound K, and others by human intestinal microflora following ingestion. Numerous studies have demonstrated beneficial effects of ginsenosides against aberrant molecular processes responsible for cancer, metabolic diseases and neurodegenerative diseases. Recently, antiaging effects of ginsenosides in human skin have been reported from clinical trial and in vitro model data. Ginsenosides have hence been proposed as promising natural cosmeceutical agents. In this review, we will critically review the known biological effects of several ginsenosides (Rb1, Rg3, Rd and compound K), such as anti-inflammatory and anticancer activities, which arise from the modulation of diverse molecular pathways. The application potential of ginsenosides as cosmeceutical ingredients will also be reviewed.