Chen Haihong, Nie Qixing, Hu Jielun, Huang Xiaojun, Yin Junyi, Nie Shaoping
State Key Laboratory of Food Science and Technology, China-Canada Joint Laboratory of Food Science and Technology (Nanchang), Nanchang University, 235 Nanjing East Road, Nanchang, Jiangxi 330047, People's Republic of China.
J Agric Food Chem. 2021 Mar 3;69(8):2632-2645. doi: 10.1021/acs.jafc.0c07871. Epub 2021 Feb 19.
Type 2 diabetes (T2D) is a worldwide epidemic associated with metabolic disorders and intestinal microbiota alterations. Polysaccharides have been considered to be beneficial to the prevention and alleviation of T2D. In the present study, ultra-performance liquid chromatography-triple-time-of-flight-based metabolomics and proteomics and 16S rRNA sequencing methods were employed to evaluate the effects of glucomannans from stem, konjac, and leaves on host metabolism and intestinal microbiota regulation in type 2 diabetic rats and potential mechanisms. The metabolism of amino acids was significantly disturbed in the type 2 diabetic rats, especially the upregulated branched-chain amino acid (BCAA) metabolism. Host-derived BCAA metabolism was significantly decreased in type 2 diabetic rats. However, the levels of BCAAs in host circulation and gene abundance of BCAA biosynthesis in gut microbiota were significantly increased in diabetic rats, which suggested that the disturbed intestinal microbiota might be responsible for the increased circulation of BCAAs in T2D. Glucomannan treatment decreased the abundance of microbial BCAA biosynthesis-related genes and ameliorated the host BCAA metabolism. Also, glucomannan with a higher molecular weight and a lower ratio of mannose/glucose possessed better antidiabetic effects. In summary, the antidiabetic effects of glucomannans might be associated with the amelioration of BCAA metabolism by modulating intestinal microbiota.
2型糖尿病（T2D）是一种全球性的流行病，与代谢紊乱和肠道微生物群改变有关。多糖被认为对T2D的预防和缓解有益。在本研究中，采用基于超高效液相色谱-三重飞行时间的代谢组学和蛋白质组学以及16S rRNA测序方法，评估魔芋茎、魔芋和魔芋叶中的葡甘露聚糖对2型糖尿病大鼠宿主代谢和肠道微生物群调节的影响及潜在机制。2型糖尿病大鼠的氨基酸代谢受到显著干扰，尤其是支链氨基酸（BCAA）代谢上调。2型糖尿病大鼠宿主来源的BCAA代谢显著降低。然而，糖尿病大鼠宿主循环中BCAAs的水平和肠道微生物群中BCAA生物合成的基因丰度显著增加，这表明肠道微生物群紊乱可能是T2D中BCAAs循环增加的原因。葡甘露聚糖治疗降低了微生物BCAA生物合成相关基因的丰度，并改善了宿主BCAA代谢。此外，分子量较高且甘露糖/葡萄糖比例较低的葡甘露聚糖具有更好的抗糖尿病作用。总之，葡甘露聚糖的抗糖尿病作用可能与通过调节肠道微生物群改善BCAA代谢有关。
