Structural characterization and immunomodulatory activity of a novel acid polysaccharide isolated from the pulp of Rosa laevigata Michx fruit

• Published in: International journal of biological macromolecules 2020-02, Vol.145, p.1080-1090
• Main Authors: Zhan, Qiping, Wang, Qian, Lin, Ruge, He, Ping, Lai, Furao, Zhang, Mengmeng, Wu, Hui
• Format: Article
• Language: English
• Subjects: Animals; Cytokines - metabolism; Fruit - chemistry; Immunologic Factors - chemistry; Immunologic Factors - isolation & purification; Immunologic Factors - pharmacology; Immunomodulatory activity; Interleukin-6 - metabolism; Macrophages - metabolism; Mice; Molecular Weight; NF-kappa B - metabolism; Nitric Oxide Synthase Type II - metabolism; Phagocytosis; Plant Extracts - chemistry; Plant Extracts - pharmacology; Polysaccharide; Polysaccharides - chemistry; Polysaccharides - isolation & purification; Polysaccharides - pharmacology; Polysaccharides - ultrastructure; RAW 264.7 Cells; RAW264.7 cells; RNA, Messenger - metabolism; Rosa - chemistry; Rosa laevigata Michx; Signal Transduction - drug effects; Structural characterization; Tumor Necrosis Factor-alpha - metabolism
• ISSN: 0141-8130; 1879-0003
• DOI: 10.1016/j.ijbiomac.2019.09.201

[Display omitted] •A polysaccharide (PPRLMF-2) was purified from pulp of Rosa laevigata Michx fruit.•The structure of PPRLMF-2 and its structure-activity relationships were elucidated.•The pattern recognition receptors of PPRLMF-2 were elucidated for the first time.•PPRLMF-2 exhibited immunomodulating activity via MAPKs/NF-κB signaling pathways. A novel acid polysaccharide (PPRLMF-2) with the Mw of 137,123 Da and a triple-helix conformation was first isolated from the pulp of Rosa laevigata Michx fruit. Structural characterization showed that PPRLMF-2 consisted of rhamnose (7.6%), arabinose (26.5%), xylose (3.5%), mannose (0.9%), glucose (5.7%), galactose (31.9%) and galacturonic acid (23.9%). The methylation and NMR (1D and 2D) analysis revealed that PPRLMF-2 contained 16 types of glycosidic linkages. The immunomodulatory activity assays indicated that PPRLMF-2 could significantly enhance phagocytosis, the secretion and mRNA expression of cytokines in RAW 264.7 cells. Additionally, SR, GR, TLR-2, and TLR-4 were the main pattern recognition receptors (PRRs) of PPRLMF-2 to upregulate the p-ERK, p-JNK, p-p38, and p-p65. These results suggested that PPRLMF-2 could recognize the PRRs of the macrophages to enhance the immunomodulatory activity via activation of the MAPKs and NF-κB signaling pathways. This study provides important implications of PPRLMF-2 as an attractive immunomodulatory functional food.