Abstract

Dipeptidyl peptidase is a crucial enzyme that regulates glucose metabolism by degrading incretins, such as glucagon-like-peptide-1, thereby reducing insulin secretion from the pancreatic β-cells. Consequently, dipeptidyl peptidase-IV inhibitors are an important remedial approach to moderate the hyperglycemic pathophysiology. A pyruvylated polysaccharide characterized as [→3)-4,6-O-(1-carboxyethylidene)-β-D-galp-(2SO₃⁻)-(1→4)-3,6-α-L-AnGalp-(2OMe)-(1→], isolated from the marine macroalga Hydropuntia edulis, showed attenuation potential against dipeptidyl peptidase-IV (IC₅₀ 4.44 μM). The structure was elucidated using mass and one/two-dimensional nuclear magnetic resonance spectroscopic analyses of hydrolyzed polysaccharide besides glycosidic linkages obtained from partially methylated alditol acetate derivative. The isolated polysaccharide also revealed potential anti-carbolytic properties against α-amylase/α-glucosidase (IC₅₀ 45–47 μM). The results proved the candidacy of pyruvylated polysaccharide isolated from H. edulis as a potential therapeutic lead against hyperglycemia.

摘要

二肽基肽酶是一种重要的酶，它通过降解肠促胰岛素（例如胰高血糖素样肽-1）来调节葡萄糖代谢，从而减少胰腺β细胞的胰岛素分泌。因此，二肽基肽酶-IV 抑制剂是缓解高血糖病理生理学的重要治疗方法。一种丙酮酰化多糖，其特征为 [→3)-4,6- O -(1-羧基亚乙基)- β -D-gal p -(2SO ₃ ⁻ )-(1→4)-3,6- α -L-AnGal p -(2OMe)-(1→]，从海洋大型藻类Hydropuntia edulis中分离出来，显示出对二肽基肽酶-IV 的衰减潜力 (IC ₅₀ 4.44  μM )。使用质量和一维/二维核磁共振阐明了结构除了从部分甲基化的糖醇乙酸酯衍生物获得的糖苷键之外，还对水解多糖进行了光谱分析。分离的多糖还揭示了针对α-淀粉酶/ α-葡萄糖苷酶的潜在抗碳水化合物特性（IC ₅₀ 45–47  μM）。结果证明了从H. edulis中分离出的丙酮酰化多糖作为对抗高血糖的潜在治疗药物。