Plant polysaccharides mitigate ionizing radiation injury via multi-tissue protection and multi-target mechanisms: A...

Increased utilization of radiation-based technologies elevates human exposure to ionizing radiation (IR), posing significant biological risks. Plant polysaccharides, naturally occurring macromolecules characterized by excellent biocompatibility, favorable safety profiles, and diverse biological activities, show promise as radioprotective agents. Evidence indicates that specific plant polysaccharides exert multi-target protective effects against IR. This review synthesizes research progress (2014-present) on the radioprotective efficacy of plant polysaccharides in critical radiosensitive systems, including hematopoietic, gastrointestinal (GI), and reproductive tissues. Key protective mechanisms involve attenuation of oxidative stress, modulation of immune homeostasis, and regulation of apoptotic pathways. Structure-activity relationships of representative radioprotective polysaccharides are analyzed through specific case studies, highlighting their structural diversity. Current challenges stem primarily from the inherent structural heterogeneity of polysaccharides, which hinders pharmaceutical standardization and clinical translation. Strategically, developing functional foods leveraging their established dietary safety offers a viable approach to circumvent these barriers while providing foundational safety and bioactivity data for future drug development.