Stimulation of Innate Immune Function by Panax ginseng after Heat Processing

Area of Science:

• Immunology
• Pharmacology
• Natural Products

Background:

• Panax ginseng (Ginseng) is traditionally used to enhance immune function.
• White ginseng (WG) and heat-processed ginseng (HPG) possess distinct phytochemical profiles.
• Understanding their differential effects on innate immunity is crucial.

Purpose of the Study:

• To compare the innate immune-stimulating effects of WG and HPG.
• To elucidate the molecular mechanisms underlying HPG's immunomodulatory actions in RAW264.7 cells.

Main Methods:

• Liquid chromatography-mass spectrometry (LC-MS) for ginsenoside profiling.
• Assays for NF-κB transcriptional activity, cytokine production (IL-6, TNF-α), and MHC expression.
• Western blotting to assess MAPK and NF-κB pathway phosphorylation.
• Inhibitor studies targeting specific signaling pathways (ERK, JNK, p38, IκBα).

Main Results:

• HPG contains unique ginsenosides (Rg3, Rk1, Rg5) not found in WG.
• HPG, but not WG, enhanced NF-κB activity, IL-6 and TNF-α production, and MHC class I/II expression.
• HPG activated MAPK and NF-κB signaling pathways.
• The ERK/c-Jun pathway was identified as critical for HPG-induced macrophage activation and cytokine production.

Conclusions:

• Heat processing alters ginseng's ginsenoside composition, leading to enhanced immunomodulatory properties.
• HPG effectively stimulates innate immunity in macrophages via the ERK/c-Jun signaling pathway.
• HPG demonstrates potential as a functional food ingredient for immune system support.