A recent study highlights a mushroom-stem polysaccharide called PGSP from Pleurotus geesteranus that may enhance glucose uptake in insulin-resistant liver cells, offering potential for new functional foods targeting metabolic dysfunctions.
A study in Scientific Reports has identified a mushroom-stem polysaccharide that may help improve glucose handling in insulin-resistant liver cells, adding to a growing body of work on fungi-derived compounds as potential functional food ingredients. The researchers focused on stems from Pleurotus geesteranus, an edible mushroom whose by-products are cheap and abundant, and extracted a purified polysaccharide they named PGSP.
Using a series of purification and analysis techniques, including chromatography, infrared spectroscopy, ion chromatography and nuclear magnetic resonance, the team found that PGSP was a homogeneous neutral polysaccharide with an α-linked pyranose structure. It contained fucose, arabinose, rhamnose, galactose, glucose, mannose and glucuronic acid, and had a relatively narrow molecular-weight distribution, suggesting a consistent molecular profile.
In cell experiments, PGSP showed no toxicity across the tested dose range and appeared to support cell growth. More importantly, at higher concentrations it improved glucose uptake in insulin-resistant HepG2 cells, a widely used liver-cell model for studying metabolic dysfunction. The results point to a direct effect on cellular glucose metabolism rather than a simple stress-response artefact.
Mechanistically, the study linked that benefit to the IRS1/GSK-3β/GLUT4 signalling pathway, which plays a central part in insulin action. At the effective dose, PGSP increased IRS1 protein levels, reduced phosphorylated GSK-3β and boosted both the movement of GLUT4 to the cell membrane and its overall expression. The findings build on earlier work on P. geesteranus stem derivatives, which have shown antioxidant activity and the ability to inhibit enzymes involved in carbohydrate digestion, and they also fit with other studies of mushroom- and plant-derived polysaccharides that have improved glucose-related measures in insulin-resistant HepG2 cells.
Disclaimer: This content is for informational purposes only and is not intended to be a substitute for professional medical judgment, advice, diagnosis, or treatment.
