Structural characterization of CYP-A from Chinese yam and its modulation of adipocyte lipolysis via the cAMP/PKA/HSL axis

Obesity is characterized by adipocyte hypertrophy and metabolic dysregulation. In this study, a novel polysaccharide (CYP-A) was isolated from Chinese yam. Structural analysis demonstrated that CYP-A is composed of α-L-Araf-(1→, α-D-Glcp-(1→, →5)-α-L-Araf-(1→, →4)-α-D-Glcp-(1→, →4,6)-α-D-Glcp-(1→, and →3,6)-β-D-Galp-(1→. Additionally, the lipolytic activities of CYP-A were evaluated using OP9 cells in vitro and zebrafish models in vivo. The essential role of the cAMP/PKA/HSL axis in mediating CYP-A-induced lipolysis was demonstrated using selective inhibitors; SQ22,536 (cAMP inhibitor) and H-89 (PKA inhibitor) abrogated the enhancement of triglyceride hydrolysis via PKA-dependent HSL phosphorylation. Furthermore, CYP-A upregulates the expression of UCP1, suggesting enhanced lipid mobilization and improved thermogenic capacity. Collectively, these findings highlight CYP-A as a promising anti-obesity nutrient that modulates adipocyte metabolism via a well-defined molecular mechanism, thereby contributing to metabolic homeostasis and providing valuable insights into its structure-function relationship.