An Alkali-extracted polysaccharide from Poria cocos activates RAW264.7 macrophages via NF-κB signaling pathway

• Published in: Arabian journal of chemistry 2023-04, Vol.16 (4), p.104592, Article 104592
• Main Authors: He, Jiaqi, Lu, Jingwu, Zhan, Lingmin, Zheng, Danping, Wang, Yingdong, Meng, Jinxin, Li, Peng, Zhao, Jinzhong, Zhang, Wuxia
• Format: Article
• Language: English
• Subjects: Alkali-extracted polysaccharide; Immunomodulatory effect; NF-κB signaling pathway; Poria cocos; β-glucan
• ISSN: 1878-5352; 1878-5379
• DOI: 10.1016/j.arabjc.2023.104592

An alkali-extracted polysaccharide (PCAPS1) was isolated and purified from the Poria cocos. Our results proved that PCAPS1 was a neutral polysaccharide with a molecular weight of 11.5 kDa. The monosaccharide composition, methylation and NMR analysis results displayed that the polysaccharide was mostly comprised of β-1,3-glucan with 1,4 and 1,6 branches. The Immune activity and mechanism of PCAPS1 were evaluated in RAW264.7 cells. The enzyme-linked immunosorbent assay (ELISA) analysis revealed that PCAPS1 increased the tumor necrosis factor-α (TNF-α) secretion. RNA-sequencing data analysis suggested that PCAPS1 activated macrophages by the classic NF-κB pathway. Real-time quantitative polymerase chain reaction (RT-qPCR) analysis confirmed that PCAPS1 enhanced mRNA expression levels of TNF-α and nuclear factor κB (NF-κB) in RAW264.7 cells. Simultaneously, the fluorescence nuclear transport experiment showed that PCAPS1 activated RAW264.7 cells by inducing the NF-κB p65 translocation. Our results indicated that PCAPS1-induced TNF-α expression was mediated via the NF-κB signaling pathway.