Abstract: Using Caenorhabditis elegans as a model organism, we systematically evaluated the anti-aging potential of polysaccharides extracted from the stems of two Zhejiang cultivars of Dendrobium officinale-Yanhu 1 (DOP1) and Shenglan 8 (DOP8). To elucidate the underlying mechanisms, lifespan, growth, development, locomotion, and stress tolerance were assessed, along with the levels of lipofuscin, reactive oxygen species (ROS), and malondialdehyde (MDA), and the transcription of aging-related genes was analyzed. The results showed that DOP1 and DOP8 extended the mean lifespan of C. elegans by 36.91% and 29.20%, respectively, and both promoted growth and development, enhanced locomotor activity, and improved antioxidant capacity and resistance to thermal stress. Molecularly, they decreased lipofuscin, ROS, and MDA levels, but via different mechanisms: DOP8 increased the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), whereas DOP1 promoted the nuclear translocation of the key transcription factors DAF-16 and SKN-1 in the insulin/IGF-1 signaling (IIS) pathway, upregulating sod-3 expression. In summary, these polysaccharides delay aging through both antioxidant and transcriptional regulatory pathways, providing a theoretical basis for developing DOP-based anti-aging drug precursors and functional foods.

Key words: Dendrobium officinale stem polysaccharides; Caenorhabditis elegans; anti-aging; antioxidant; insulin/insulin like growth factor-1 signaling pathway