Structural characterization and anti-fatigue mechanism based on the gut-muscle axis of a polysaccharide from Zingiber officinale

This study aimed to characterize the structure of polysaccharide ZOPA extracted from Zingiber officinale and its purified form (ZOPA-1), and to investigate their anti-fatigue mechanisms based on the gut-muscle axis. The study found that the backbone of ZOPA-1 is primarily composed of-*3,4)-alpha-Glcp-1-* and-*4,6)-alpha-Glcp-(1-* linkages, with-*4)-alpha-Glcp(1-* serving as its side chain. In exhaustive swimming experiments with mice, both crude ZOPA and purified ZOPA-1 demonstrated significant anti-fatigue effects, including enhanced glycogen storage, improved antioxidant capacity, reduced accumulation of metabolic waste products, and regulated energy metabolism in the gastrocnemius muscles. These effects may be mediated through the activation of the Keap1Nrf2/ARE and AMPK/PGC-1 alpha signaling pathways. Furthermore, ZOPA and ZOPA-1 modulated the intestinal flora of mice, increasing diversity, altering abundance, and regulating short-chain fatty acid concentrations, suggesting a potential role of the gut-muscle axis in mediating the anti-fatigue effects. This study provides valuable insights into the complex interplay between polysaccharides, the gut-muscle axis, and exercise-induced fatigue.