A novel galactoglucan from Ganoderma lucidum ameliorates ethanol-induced gastric ulcers by modulating FAK-MAPK...

Gastric ulcer (GU) is a prevalent gastrointestinal disorder that significantly impacts patients' quality of life. Current treatments, including proton pump inhibitors and H₂ receptor antagonists, often present limitations such as adverse side effects and incomplete healing, highlighting the urgent need for new therapeutic agents. Ganoderma lucidum polysaccharide peptides (GL-PP) have gained attention for their potential gastroprotective properties. Notably, we characterized a novel GL-PP named GL-PPQ₃, assessing its efficacy in alleviating GUs using an ethanol-induced GU mouse. Our findings indicated that GL-PPQ₃ is a hyperbranched galactoglucan with a molecular weight of 41.08 kDa, predominantly composed of glucose and galactose. Comprehensive analysis, including methylation and one-dimensional and two-dimensional nuclear magnetic resonance (NMR), elucidated its structural composition, revealing the presence of 1,6-α-D-Galp, 1,2,6-α-D-Galp, 1,6-β-D-Glcp, 1,3,6-β-D-Glcp, and 1,4-β-D-Glcp residues. X-ray diffraction (XRD) confirmed a predominantly amorphous structure and scanning electron microscopy (SEM) displayed aggregated spherical formations. Mechanistically, GL-PPQ₃ exhibited its Gastroprotective effects through the regulation of the FAK-mediated MAPK signaling pathway. This study underscores the therapeutic potential of GL-PPQ₃ as a promising candidate for GU treatment, paving the way for developing novel functional agents derived from natural sources.