Structural characterization and hypoglycaemic effects on type 2 diabetic mice of Spirulina platensis polysaccharides and Se-modified polysaccharides
Mengwei Chang, Kunlun Liu, Guangsu Zhu, Palwasha Gul, Jabir Khan
Abstract
Selenium-enriched polysaccharides refer to polysaccharides that contain selenium, which have emerged as a significant area of research in recent years due to the bioactivities associated with both polysaccharides and selenium. In this study, we prepared Spirulina platensis polysaccharides (SPP) and selenium-enriched SPP (SeSPP), and assessed their structural properties and hypoglycaemic functions both in vitro and in vivo . The results of the structural characterization indicated that SPP was successfully selenized. The interaction between SPP and selenium primarily occurred in the forms of Se-O-C and O-Se-O through covalent interactions. The molecular weight of SeSPP was found to be more concentrated compared to SPP, and its microscopic morphology exhibited greater complexity, including both rod-shaped and spherical particles. It was determined that SPP and SeSPP were mainly composed of glucose, rhamnose , and fucose . In vitro assays demonstrated that SeSPP exhibited significantly enhanced hypoglycaemic and antioxidant properties compared to SPP. In an in vivo model of streptozotocin- and high-fat diet-induced type 2 diabetes mice, SeSPP improved hypoglycaemic activity by reversing body weight , blood glucose levels , glucose tolerance, insulin resistance, lipid levels , hepatic oxidative stress levels, as well as liver and pancreatic morphology and function. Consequently, SeSPP may serve as a selenium supplement that could enhance hypoglycaemic effects.