Wei Xiaoyu, Du Peiwen, Luo Youping, Zhao Yadong, Zhou Xueming, Chen Guangying, Zhang Bin
School of Food and Pharmacy, Zhejiang Ocean University, Zhoushan 316000, China.
Key Laboratory of Tropical Medicinal Resource Chemistry of Ministry of Education, College of Chemistry and Chemical Engineering, Hainan Normal University, Haikou 571158, China.
Foods. 2025 Aug 27;14(17):2989. doi: 10.3390/foods14172989.
polysaccharides demonstrate promising hypoglycemic activity, but their high molecular weight restricts bioavailability. This study established a controlled degradation approach to optimize the functional properties of polysaccharides. Molecular characterization demonstrated that the degraded polysaccharides (DNJPs, Mw 191.8 kDa) retained the core monosaccharide composition, while exhibiting enhanced solubility. In vitro experiments with insulin-resistant HepG2 cells showed that DNJPs (0.5-2 mg/mL) significantly enhanced glucose consumption ( < 0.01) and mitigated oxidative stress by upregulating antioxidant enzymes (SOD, CAT, and GSH-Px) and decreasing malondialdehyde (MDA) levels. DNJPs activated the PI3K/AKT-Nrf2-GSK3β signaling axis through a multifaceted mechanism involving the following: upregulating the phosphorylation levels of PI3K and AKT; enhancing Nrf2 nuclear translocation, which in turn promotes the expression of downstream targets such as HO-1 and NQO1; inhibiting GSK3β activity; and suppressing FOXO1-mediated gluconeogenesis. These findings underscore DNJPs as promising functional food ingredients that modulate two key pathways to improve glucose metabolism.
多糖具有良好的降血糖活性，但其高分子量限制了生物利用度。本研究建立了一种可控降解方法来优化多糖的功能特性。分子表征表明，降解后的多糖（DNJPs，分子量191.8 kDa）保留了核心单糖组成，同时溶解性增强。对胰岛素抵抗的HepG2细胞进行的体外实验表明，DNJPs（0.5 - 2 mg/mL）显著提高葡萄糖消耗（<0.01），并通过上调抗氧化酶（超氧化物歧化酶、过氧化氢酶和谷胱甘肽过氧化物酶）和降低丙二醛水平减轻氧化应激。DNJPs通过多方面机制激活PI3K/AKT - Nrf2 - GSK3β信号轴，包括：上调PI3K和AKT的磷酸化水平；增强Nrf2核转位，进而促进下游靶点如血红素加氧酶 - 1和醌氧化还原酶1的表达；抑制GSK3β活性；以及抑制FOXO1介导的糖异生。这些发现强调了DNJPs作为有前景的功能性食品成分，可调节两个关键途径来改善葡萄糖代谢。
