Antioxidant and anti-aging activities of polysaccharides from Cordyceps cicadae

Cordyceps cicadae is a traditional Chinese medicine with high nutritional value and biological activities. Previously, we reported on the antioxidant activity associated with the polysaccharides from Cordyceps cicadae (CP). To further explore which of the fraction of CP had the greatest potency, in here, the in vitro antioxidant and in vivo anti-aging activities of the fractions CP30–CP80 of CP were evaluated. The in vitro antioxidant activity results revealed that all the fractions (i.e. CP30–CP80) were potent with CP70 as the most potent. Notably, CP70 prolonged the lifespan of Drosophila (P < 0.05), increased the activities of catalase (CAT) and glutathione peroxidase (GSH-Px) (P < 0.01), and inhibited the formation of malondialdehyde (MDA) (P < 0.01). Additionally, CP70 upregulated the expression level of antioxidant-related genes CAT, SOD1 and MTH in Drosophila (P < 0.05). These results indicated that CP70 may prolong the lifespan of Drosophila through the up-regulation of the expression level of antioxidant-related genes CAT, SOD1 and MTH in Drosophila. Thus, polysaccharides from Cordyceps cicadae possess significant antioxidant and anti-aging activities, and could be explored as a new dietary supplement to slow down the aging process.