Abstract:[Objective]This study explored the antioxidant activity and exercise fatigue-alleviating effect of Chlamydomonas reinhardtii-derived extracellular vesicles (CLEVs), aiming to provide a reference for the application of microalgae-derived extracellular vesicles in the field of sports nutrition.[Method]CLEVs were isolated by ultracentrifugation, and their antioxidant and anti-fatigue effects were evaluated through in vitro and in vivo experiments.[Result]CLEVs exhibited typical cup- or bowl-shaped morphology with an average particle size of (88.35±0.36) nm. CLEVs demonstrated concentration-dependent antioxidant activity in vitro and effectively scavenged DPPH and ABTS+ free radicals. In the H2O2-induced oxidative damage model, CLEVs increased the levels of superoxide dismutase (SOD) and reduced glutathione (GSH), decreased the levels of malondialdehyde (MDA), lactate dehydrogenase (LDH), creatine kinase (CK), and lactic acid (LA), and promoted glycogen storage. Animal experiments showed that CLEVs significantly prolonged the load swimming time to exhaustion and enhanced the antioxidant defense by upregulating the expression of Nrf2 and downregulating the expression of Keap1.[Conclusion]CLEVs could alleviate exercise fatigue by ameliorating oxidative stress, promoting energy metabolism, and activating the Nrf2/Keap1 signaling pathway, demonstrating potential application in sports nutrition and the development of anti-fatigue products.
