Polysaccharide from Ganoderma atrum delay senescence and enhance stress resistance through modulating IIS and MAPK pathway in Caenorhabditis elegans

Ganoderma atrum is an edible and medicinal fungi in oriental countries with various bioactivities, such as antioxidant, anti-inflammatory and anti-aging properties. The study was to evaluate the effects of polysaccharide from Ganoderma atrum (PSG) on lifespan, healthspan (locomotion, pumping, lipofuscin, ROS, chemotaxis and intestinal permeability) and defense system (stress resistance, antioxidant enzymes activities), as well as to investigate its anti-aging mechanism in Caenorhabditis elegans . The findings indicated that PSG prolonged the lifespan (optimal concentration at 400 μg/mL, with an increased average lifespan by 23.10 %) and improved senescence-related physiological indicators of worms. Furthermore, the lipid accumulation was reduced, while stress resistance and antioxidant enzymes activities were enhanced after PSG intervention. Meanwhile, studies with mutants demonstrated that DAF-16/FOXO and SKN-1/Nrf-2 were required for lifespan-extension, which might be attributed to the IIS and MAPK pathways. Overall, these demonstrated that PSG was a potential dietary supplement to promote health and ameliorate aging-associated pathologies.