The physiochemical characteristics of Cyclocarya paliurus polysaccharides and in vitro anti-diabetic effects of their different fractions

To efficiently develop and utilize Cyclocarya paliurus polysaccharides, we determined the physicochemical properties and evaluated the in vitro anti-diabetic effects of C. paliurus using different fractions of their polysaccharides. The C. paliurus polysaccharides powder had the characteristic physiochemical reaction of polysaccharides with low fluidity. The IC50 value of the α-glucosidase inhibitory activity of C. paliurus polysaccharide fraction 4 was 14.05 ± 0.13 μg/mL. At 100 μg/mL, both C. paliurus polysaccharide fractions 1 and 6 depicted no toxicity to pancreatic β-cells. Moreover, fraction 1 recovered the insulin mRNA expression level of β-TC6 cells treated using high glucose. C. paliurus polysaccharide fractions 1, 2, and 6 significantly enhanced insulin secretion from pancreatic β-cells. All the components of C. paliurus polysaccharides promoted 2-NBDG uptake using hepatocytes HepG2. The C. paliurus polysaccharide fraction 1 depicted the highest application potential in diabetes mellitus treatment due to its low toxicity, high insulin production, and strong protection against apoptosis. Further studies should focus on the sugar composition of C. paliurus polysaccharide fractions 1 and 6 and the mechanisms underlying their molecular effect while treating type 2 diabetes mellitus.