Effects of Glycosaminoglycan from Urechis Unicinctus on the P₂Y₁₂ Receptor Signaling Pathway in Rat Platelets

This study aims to investigate the effects of glycosaminoglycan (GAG) from Urechis unicinctus on the P₂Y₁₂ receptor signaling pathway in rat platelets. The concentrations of cyclic adenosine monophosphate (cAMP), thromboxane B2 (TXB₂) and glycoprotein IIb/IIIa (GPIIb/IIIa) in rat platelets were determined using enzyme-linked immunosorbent assay (ELISA) kits. The phosphorylation levels of protein kinase A (PKA) and vasodilator-stimulated phosphoprotein (VASP) in rat platelets were detected through Western blot. The expression of P₂Y₁₂ gene in rat platelets was analyzed via real-time fluorescence quantitative PCR and reverse-transcription PCR. It was observed that GAG significantly increased the cAMP content (p <0.05, p <0.01) and decreased the TXB2 and GPIIb/IIIa concentrations (p <0.05, p <0.01) in rat platelets. GAG significantly enhanced the phosphorylation levels of PKA and VASP in rat platelets (p <0.01) and had a synergistic effect with the P₂Y₁₂ receptor blocker. GAG significantly reduced the expression level of P₂Y₁₂ gene in rat platelets (p <0.01). We speculated that GAG from U. unicinctus inhibited platelet aggregation in rats through the P₂Y₁₂ receptor signaling pathway.