Polysaccharides from Millettia speciosa Champ. Ameliorates Excessive Exercise-Induced Fatigue by Regulating Gut Microbiota

This study aimed to explore the ameliorative effect of Millettia speciosa Champ. polysaccharides (MSP) on excessive exercise-induced fatigue (EF) mice. The physicochemical characterization and in vitro antioxidant activities were analyzed. The fatigue-related biochemical indexes were determined, and gut microbiota was analyzed by 16S rDNA sequencing. The results showed that MSP primarily consists of total carbohydrates, uronic acids, and proteins. It was mainly composed of glucose, arabinose, and galactose. Additionally, MSP showed good scavenging effects on free radicals. In the experiment of EF mice, MSP intervention effectively extended the pole-climbing and swimming time, significantly increased the levels of muscle and liver glycogen, blood glucose, adenosine triphosphate, glutathione peroxidase, and superoxide dismutase, while significantly decreased the levels of fatigue-related lactate dehydrogenase, creatine kinase, and urea nitrogen. Furthermore, MSP intervention reduced harmful bacteria (Helicobacter, Anaerotruncus, Erysipelatoclostridium, and Lachnospiraceae_FCS020_group), and enriched the beneficial bacteria (Lactobacillus, Alistipes, Ruminococcaceae, and Roseburia). Therefore, MSP may utilize the gut microbiota as a target to alleviate fatigue caused by excessive exercise.