Targeting neurodegenerative diseases with bioactive oligosaccharides: Mechanisms and prospects

With the intensification of global aging, neurodegenerative diseases (NDs) such as Parkinson's disease and Alzheimer's disease present a growing challenge, severely impacting patients' quality of life. Current treatments primarily offer symptomatic relief with limited efficacy and notable side effects, highlighting the need for novel therapeutic strategies. Oligosaccharides, low-molecular-weight carbohydrates derived from polysaccharide hydrolysis or synthesis, have emerged as promising multifunctional agents due to their diverse bioactivities. They exhibit unique advantages over conventional drugs by simultaneously targeting multiple pathological mechanisms: modulating gut-brain axis communication, suppressing neuroinflammation, enhancing autophagy, and inhibiting toxic protein aggregation. Their neuroprotective effects are strongly influenced by structural features, including glycosidic bond types, molecular size, and functional modifications, which collectively determine their biological activity and specificity. This review summarizes the therapeutic applications of oligosaccharides in NDs, elucidates their multifaceted mechanisms of action, and explores the key structure-activity relationships, providing a foundation for developing oligosaccharide-based interventions with disease-modifying potential for neurodegenerative pathologies.