Location of Thesis Examination

Room 3021 Dental Science Building

Degree

Master of Science

Program

Microbiology and Immunology

Supervisor

Dr. Joaquín Madrenas

Abstract

Ginseng has played a vital role in traditional Chinese medicine for thousands of years. There are 22 variants of ginseng including North American ginseng (Panax quinquefolius) and Asian ginseng (Panax ginseng). The use of North American ginseng has increased dramatically and there is a strong need to understand its immunomodulatory effects. This is because the majority of current research focusing on the Asian ginseng variant. Human peripheral blood mononuclear cells (PBMC) were used to test the immunomodulatory properties of 3 North American ginseng extracts, COLD-FX® and deglycosylated individual ginsenosides. Microarray analysis of PBMC exposed to the aqueous ginseng extract was used to determine the induced transcriptional profile. The aqueous ginseng extract induced a Th1 transcriptional profile likely by modulating the MAPK (ERK-1/2), PI3K, p38 and NF-κB signalling pathways. The high molecular weight polysaccharides of North American ginseng induced the production of pro-inflammatory cytokines and decreased the adaptive T cell response to superantigen. These responses were antagonized by deglycosylated ginsenosides that also antagonized the induction of pro-inflammatory cytokines in LPS stimulation of PBMC. Based on these results, ginseng polysaccharides and ginsenosides are immunomodulatory, inducing a Th1 transcriptional profile. Our results may assist the development of optimized ginseng preparations with targeted immunomodulatory activity.