Structural characterization of Euglena gracilis polysaccharide and its in vitro hypoglycemic effects by alleviating insulin resistance.

Abstract

Diabetes mellitus, characterized by hyperglycemia and insulin resistance, is a disorder of the endocrine metabolic system which has emerged as a common chronic disease worldwide. Euglena gracilis polysaccharides have ideal development potential in the treatment of diabetes. However, their structure and bioactivity are largely unclear. A novel purified water-soluble polysaccharide (EGP-2A-2A) from E. gracilis with a molecular weight of 130.8 kDa consisted of xylose, rhamnose, galactose, fucose, glucose, arabinose, and glucosamine hydrochloride. The SEM image for EGP-2A-2A suggested a rough surface with the presence of globule-like protrusions. Methylation and NMR spectral analyses revealed that EGP-2A-2A was mainly composed of →6)-β-D-Galp-(1 → 2)-α-D-Glcp-(1 → 2)-α-L-Rhap-(1 → 3)-α-L-Araf-(1 → 6)-β-D-Galp-(1 → 3)-α-D-Araf-(1 → 3)-α-L-Rhap-(1 → 4)-β-D-Xylp-(1 → 6)-β-D-Galp-(1 → with complex branching structure. EGP-2A-2A significantly increased glucose consumption and glycogen content in IR-HeoG2 cells and modulates glucose metabolism disorders by regulating PI3K, AKT, and GLUT4 signaling pathways. EGP-2A-2A significantly suppressed TC, TG, and LDL-c levels, and enhanced that of HDL-c. EGP-2A-2A ameliorated abnormalities caused by disorders of glucose metabolism and the hypoglycemic activity of EGP-2A-2A may be mainly positively related to its high glucose content and the β-configuration in the main chain. These results suggested that EGP-2A-2A played an important role in alleviating disorders of glucose metabolism through insulin resistance and has the potential for development as a novel functional food with nutritional and health benefits.

• Authors: Xiaozhou Huang, Yuxi Wen, Yihan Chen, Yuanyuan Liu, Chao Zhao
• Journal: International journal of biological macromolecules (Int J Biol Macromol) Vol. 236 Pg. 123984 (May 01 2023) ISSN: 1879-0003 [Electronic] Netherlands
• PMID: 36906209 (Publication Type: Journal Article)
• Copyright: Copyright © 2023 Elsevier B.V. All rights reserved.

Chemical References

• Hypoglycemic Agents
• Polysaccharides
• Glucose

Topics

• Humans
• Hypoglycemic Agents (pharmacology, chemistry)
• Euglena gracilis
• Insulin Resistance
• Polysaccharides (chemistry)
• Glucose (analysis)