Polysaccharide PRM3 from Rhynchosia minima root enhances immune function through TLR4-NF-κB pathway

Area of Science:

• Immunology
• Pharmacology
• Natural Products

Background:

• Polysaccharides in herbal medicine are known to boost innate immunity against infections.
• Rhynchosia minima root contains polysaccharides with potential immunomodulatory properties.

Purpose of the Study:

• To investigate the in vitro and in vivo immunoregulatory effects of polysaccharides from Rhynchosia minima root.
• To explore the underlying molecular mechanisms, including the Toll-like receptor 4 (TLR4)-NF-κB signaling pathway.

Main Methods:

• Isolation and characterization of polysaccharide fractions from R. minima root.
• In vitro assays measuring nitric oxide (NO) and cytokine (TNF-α, IL-6, MCP-1) levels, macrophage phagocytosis, and NF-κB pathway activation.
• In vivo studies evaluating serum cytokine levels, T-lymphocyte subsets (CD3+, CD4+, CD8+), and the efficacy against cyclophosphamide-induced immunosuppression in mice.

Main Results:

• PRM3 significantly enhanced macrophage phagocytic activity and increased NO and cytokine (TNF-α, IL-6, MCP-1) release.
• PRM3 activated the TLR4-NF-κB signaling pathway and increased serum cytokine levels in vivo.
• PRM3 treatment elevated CD3+, CD4+ T lymphocytes, the CD4+/CD8+ ratio, and effectively reversed cyclophosphamide-induced immunosuppression.

Conclusions:

• Rhynchosia minima root polysaccharide PRM3 demonstrates potent immunoenhancing activity both in vitro and in vivo.
• The mechanism involves activation of the TLR4-NF-κB pathway, leading to improved immune cell function and alleviation of immunosuppression.
• PRM3 is a promising candidate for development as an immunopotentiator in functional foods or therapeutic drugs.