Antioxidant and Antiaging Effects and Mechanism of Action of Gynura divaricata (L.) DC Polysaccharides in Caenorhabditis elegans

ABSTRACT With the increasing prominence of population aging, antiaging research has garnered significant attention. This study investigated the antioxidant and antiaging effects of a crude Gynura divaricata polysaccharide (GDP) and its purified fractions (GDP1, GDP3), prepared via a H 2 O 2 /Vc‐assisted method. All GDPs exhibited potent radical‐scavenging activity in vitro. In a Caenorhabditis elegans model, GDPs significantly extended lifespan (up to 19.17%), enhanced motility, and increased heat stress resistance. Treatment with 2 mg/mL GDP markedly reduced lipofuscin accumulation by 43.6% and elevated superoxide dismutase (SOD) and catalase (CAT) activities. GDP demonstrated the strongest effects. Mechanistic studies revealed GDP upregulates daf‐16 , sod‐3 , and skn‐1 while downregulating daf‐2 and age‐1 . Crucially, the lifespan‐extending effect of GDP was abolished in daf‐16 mutants, demonstrating that their antiaging action operates primarily via the insulin/IGF signaling (IIS) pathway.