Project: The Role of Microbiome in the Ginseng Metabolism and Cancer
University Association: UH College of Pharmacy Texas Medical Center
Collaborator Name: Ming Hu, Ph.D.
Ginsenosides are the major active ingredients for the reported activities of ginseng, an herb that has been used for at least a thousand years in East Asian countries such as China, Japan and South Korea. The reported biological activities of ginsenosides include anticancer, anti-diabetic, and pro-cardiovascular effects.
For example, ginsenosides such as Rh2s and aglycones such as PPD, derived from chemical processing have demonstrated excellent inhibitory activities against lung cancer cells in culture. We have also shown that “processed” ginsenosides (Rh2s and aglycone) rather than natural ginsenosides have better bioavailability in A/J mice, which are either not absorbed or are not bioavailable.
It is hypothesized that the action of the intestinal microbiome is necessary to activate ginsenosides since many of the ß-glycosidases required to convert ginsenosides to an active form are present in microbes. Therefore, an important question is which ß-glycosidases encoded by intestinal microbiota activate ginsenosides and aglycones. Additional intriguing and novel questions are:
- Can ginsenosides affect the intestinal microbiome community structure?
- Can altering the intestinal microbiome through dietary supplementation of specific bacteria increase the bioavailability of ginsenosides?
Therefore, the central hypothesis of this research is that the intestinal microbiome encodes the enzymatic activities required to convert natural ginsenosides into bioavailable ginsenosides and that manipulation of the intestinal microbiome will generate more bioavailable ginsenosides, which will lead to higher bioavailability in vivo. This project will characterize the enzymatic activities encoded in the microbiome that convert red ginseng extracts into active species and the organisms that encode them.
Further, we will examine whether manipulation of the intestinal microbiome can affect the production and pharmacokinetics of active ginsenosides. If successful, this would provide the basis for human chemoprevention trials that will result in more effective use of ginsenosides.