College of Food Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
Department of Pharmacy, State University of Bangladesh, Dhaka 1205, Bangladesh.
Carbohydr Polym. 2018 Oct 15;198:452-461. doi: 10.1016/j.carbpol.2018.06.077. Epub 2018 Jun 18.
A novel heteropolysaccharide from Grifola frondosa named GFP-W has been isolated and purified by DEAE Sephadex A-52 chromatography. Gas chromatography, fourier transform infrared spectroscopy, one-dimensional (H- and C-) and two-dimensional (H-H COSY, H-C HSQC, and H-C HMBC) nuclear magnetic resonance spectroscopy were used to characterize its structure. The average molecular weight of GFP-W was 66.1 kDa. GFP-W mainly contained four kinds of linkage type units as β-D-GlcpA→, 1,2,6-α-Gal, →2)-α-Manp→, and →3)-α-L-Fucp-(1→. It could significantly increase the uptake of glucose in dexamethasone induced insulin resistant HepG2 cells by improving the mRNA and protein expression of insulin receptor substrate 1, phosphatidylinositol-3-kinase, and glucose transporter 4 upregulation and c-Jun N-terminal Kinase 1 downregulation. Moreover, antidiabetic activities of GFP-W were associated with significant changes in the extent of protein lysine acetylation, crotonylation, and succinylation levels. Our results provide a new hypoglycemic therapeutic role and an in-depth analysis on molecular mechanisms upon polysaccharides from G. frondosa.
从灰树花中分离得到一种新型杂多糖 GFP-W，并通过 DEAE Sephadex A-52 层析进行纯化。采用气相色谱、傅里叶变换红外光谱、一维（H 和 C-）和二维（H-H COSY、H-C HSQC 和 H-C HMBC）核磁共振波谱对其结构进行了表征。GFP-W 的平均分子量为 66.1 kDa。GFP-W 主要含有四种键合类型的单元，即β-D-GlcpA→、1,2,6-α-Gal、→2)-α-Manp→和→3)-α-L-Fucp-(1→。它可以通过提高胰岛素受体底物 1、磷酸肌醇-3-激酶和葡萄糖转运蛋白 4 的 mRNA 和蛋白表达水平，以及下调 c-Jun N-末端激酶 1 的表达，显著增加地塞米松诱导的胰岛素抵抗 HepG2 细胞对葡萄糖的摄取。此外，GFP-W 的降血糖活性与蛋白赖氨酸乙酰化、丙二酰化和琥珀酰化水平的显著变化有关。我们的研究结果为灰树花多糖提供了新的降血糖治疗作用和分子机制的深入分析。
