Preparation of chitin derived oligosaccharide monomers, evaluation of in vitro hypoglycemic activity and investigation of potential mechanisms.

Type 2 diabetes mellitus (T2DM) is a metabolic disorder affecting people worldwide. Chitin derived oligosaccharides (CDOS), composed of glucosamine (GlcN, D) and N-acetylglucosamine (GlcNAc, A), hold potential for development as functional foods and pharmaceuticals for long-term glycemic management in patients with T2DM. However, most existing research objects are complex CDOS mixtures, with unclear structure-activity relationships. This complexity limits efforts to enhance the activity and applications of CDOS. In this study, fully deacetylated and fully N-acetylated CDOS monomers with a degree of polymerization of 2-6 were isolated. Subsequently, by integrating in vitro cellular activity assays, network pharmacology, molecular docking, molecular dynamics simulations, and real-time quantitative polymerase chain reaction (qRT-PCR) techniques, the key components of CDOS were identified, and their potential mechanisms of action were explored. Screening using in vitro cell models revealed that the D2-4 monomers and mixtures exhibited the best effects in improving glucose consumption and insulin secretion. Molecular docking and molecular dynamics simulations offered computational insights into the potential binding modes and structural stability of the interactions between the candidate target protein p110α and the D2-D4 monomers. Furthermore, qRT-PCR experiments demonstrated that the D2-4 mixture and monomers modulated the expression of glucose metabolism-related genes involved in the PI3K/AKT/GLUT2/GSK3β signaling pathway in IR-HepG2 cells. These findings provide theoretical and data support for the development of chitin derived oligosaccharides into more effective blood glucose management products.