Secoisolariciresinol Diglucoside Delays the Progression of Aging-Related Diseases and Extends the Lifespan of Caenorhabditis elegans via DAF-16 and HSF-1

Secoisolariciresinol diglucoside (SDG) is a phytoestrogen and rich in food flaxseed, sunflower seeds, and sesame seeds. Among the beneficial pharmacological activities of SDG on health, many are age related, such as anticancer, antidiabetes, antioxidant, and neuroprotective effects. Thus, we investigated if SDG had an effect on antiaging in Caenorhabditis elegans (C. elegans). Our results showed that SDG could extend the lifespan of C. elegans by up to 22.0%, delay age-related decline of body movement, reduce the lethality of heat and oxidative stress, alleviate dopamine neurodegeneration induced by 6-hydroxydopamine (6-OHDA), and decrease the toxicity of Aβ protein in C. elegans. SDG could increase the expression of the downstream genes of DAF-16, DAF-12, NHR-80, and HSF-1 at mRNA level. SDG could not extend the lifespan of mutants from genes daf-16, hsf-1, nhr-80, daf-12, glp-1, eat-2, and aak-2. The above results suggested that SDG might enhance the stress resistance, delay the progression of aging-related diseases, and extend the lifespan of C. elegans via DAF-16 and HSF-1.