Hypoglycemic effect of W/O/W emulsion encapsulating Polygonatum sibiricum polysaccharides and saponins in a mouse model of T2DM

• Firstly combining W/O/W emulsion with PSP/PSS for developing functional foods. • W/O/W emulsion-embedded PSP/PSS shows excellent hypoglycemic activity in T2DM mice.. • PSP/PSS in W/O/W emulsion differentially regulates gut microbiota in T2DM mice. • W/O/W emulsion’s delivery advantage enhances PSP/PSS bioavailability vs. single-component emulsion. This study explores the hypoglycemic efficacy of W/O/W emulsion co-encapsulating Polygonatum sibiricum polysaccharides (PSP) and saponins (PSS). In streptozotocin/high-fat diet-induced type 2 diabetes mellitus (T2DM) mice, the encapsulated PSP/PSS exhibited excellent activity: reversing typical "three more and one less" symptoms, and significantly improving blood glucose, glucose tolerance, insulin resistance, lipids, liver oxidative stress, liver glycogen, and liver/kidney morphology. After 4 weeks of intervention, the fasting blood glucose (FBG) reduction rate of the co-encapsulation group (PPE) was 20%, the homeostasis model assessment of insulin resistance (HOMA-IR) decreased by 35%, and the hepatic glycogen content increased by 122%. Meanwhile, PSP/PSS exerted effects by regulating intestinal beneficial microbiota, Akkermansia and Lactobacillus abundances in the PPE group were 1.8-fold and 2.3-fold higher than those in the diabetic model group (DC), respectively, which was more significant than the microbial regulatory effect of the PSP-only emulsion group (PE). Compared with PE group, the co-encapsulation system showed more prominent efficacy, highlighting multi-component synergistic delivery advantages. This study first confirms that W/O/W emulsion-based PSP/PSS delivery system effectively improves diabetic pathology, providing an innovative paradigm for integrating novel functional food delivery technologies with traditional medicine-food homologous plants.