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

• Published in: Biochimica et biophysica acta. General subjects Vol. 1862; no. 8; pp. 1751 - 1759
• Main Authors: Jia, Xuejing, Liang, Yeer, Zhang, Chao, Wang, Kai, Tu, Yanbei, Chen, Meiwan, Li, Peng, Wan, Jian-Bo, He, Chengwei
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.08.2018
• Subjects: active ingredients; Animals; blood serum; CD4-positive T-lymphocytes; Cells, Cultured; chemokine CCL2; chromatography; confocal microscopy; cyclophosphamide; Cytokines - metabolism; enzyme-linked immunosorbent assay; Fabaceae - chemistry; functional foods; gene expression; Gene Expression Regulation - drug effects; herbal medicines; immune response; Immunomodulation; immunostimulants; immunosuppression; interleukin-6; macrophages; Macrophages - drug effects; Macrophages - immunology; Macrophages - metabolism; messenger RNA; Mice; Mice, Inbred C57BL; Mice, SCID; NF-kappa B - metabolism; NF-κB; nitric oxide; phagocytosis; Plant Roots - chemistry; Polysaccharide; polysaccharides; Polysaccharides - chemistry; Polysaccharides - isolation & purification; Polysaccharides - pharmacology; quantitative polymerase chain reaction; Rhynchosia; Rhynchosia minima root; secretion; signal transduction; Signal Transduction - drug effects; spectroscopy; spleen; splenocytes; Toll-like receptor 4; Toll-Like Receptor 4 - metabolism; transcription factor NF-kappa B; tumor necrosis factor-alpha; NF-κB; Immunomodulation; Polysaccharide; Rhynchosia minima root; Toll-like receptor 4
• ISSN: 0304-4165; 1872-8006
• DOI: 10.1016/j.bbagen.2018.05.012

Polysaccharides, one of the active ingredients in herbal medicine, are proved to enhance innate immunity against infections. The aim of this study is to explore the immunoregulatory ability of polysaccharides from Rhynchosia minima root in vitro and in vivo. Polysaccharide fractions of R. minima root were obtained by chromatographic column. The content of NO was measured by spectrophotometry. The levels of cytokines (tumor necrosis factor-α, TNF-α; interleukin-6, IL-6; and monocyte chemoattractant protein-1, MCP-1) were determined by enzyme-linked immuno-sorbent assay (ELISA) kits. The translocation of p65 into the nucleus was imaged by confocal microscopy. The mRNA expression of TNF-α, IL-6, and MCP-1 was determined by quantitative real-time PCR. T-lymphocyte subgroups of spleen from immunosuppressive mouse were evaluated by flow cytometry. PRM3 remarkably enhanced the phagocytic ability of macrophages and promoted the release of NO and the secretion of cytokines (TNF-α, IL-6, and MCP-1) from macrophages. Simultaneously, PRM3 potently activated NF-κB signaling pathway via Toll-like receptor 4 (TLR4). In addition, PRM3 obviously increased the levels of serum cytokines, markedly up-regulated the percentages of CD3+ and CD4+ T lymphocytes and the CD4+/CD8+ ratio of splenocytes, and effectively attenuated cyclophosphamide induced immunosuppression in mice. PRM3 profoundly enhanced the immune function in vitro and in vivo through TLR4-NF-κB pathway and is a promising candidate of immunopotentiator which could be applied in functional foods or drugs. This study reported a polysaccharide PRM3 from R. minima root exhibited potent immunoenhancing activity and significantly alleviated cyclophosphamide-induced immunosuppression through TLR4-NF-κB pathway. •PRM3 was nontoxic and promoted the productions of NO, TNF-α, IL-6 and MCP-1 in vitro.•PRM3 activated RAW 264.7 cells via TLR4/NF-κB signaling pathway in vitro.•PRM3 alleviated CTX-mediated immune dysfunction in vivo.