College of Food Science and Technology, Shanghai Ocean University, Shanghai, P. R. China.
J Food Biochem. 2021 Sep;45(9):e13872. doi: 10.1111/jfbc.13872. Epub 2021 Jul 23.
Dipeptidyl peptidase-IV (DPP-IV) inhibitors can reduce the blood sugar levels of diabetic patients by preventing the rapid decomposition of incretin hormone and prolonging its physiological effects. In this study, DPP-IV inhibitory peptides FAGDDAPR and LAPPRGSL were isolated from defatted Antarctic krill powder (DAKP) protein by the sequential purification of ultrafiltration, gel filtration chromatography, and RP-HPLC, and IC values of the two peptides were 349.70 ± 3.66 μM and 461.14 ± 0.87 μM, respectively. The FAGDDAPR and LAPPRGSL were identified by LC-MS/MS method, and the molecular models of DPP-IV and the two peptides were further constructed by AutoDock Vina software, the results revealed that the inhibition activity of FAGDDAPR and LAPPRGSL was mainly attributed to the formation of strong hydrophobic interactions and hydrogen bonds with amino acids of DPP-IV. PRACTICAL APPLICATIONS: DAKP is an economical by-product produced in the production of krill oil and contains high-quality protein, but these products were mainly used as fish feed and had low utility value in the past. DPP-IV inhibitors are an efficacious drug employed in the treatment of hyperglycemia processes. However, these drugs can cause undesirable side effects. Thus, the development of new natural hypoglycemic drugs with low side effects is a valuable strategy to be applied in therapeutic interventions.
二肽基肽酶-IV（DPP-IV）抑制剂可通过阻止肠促胰岛素激素的快速分解并延长其生理作用来降低糖尿病患者的血糖水平。在这项研究中，通过超滤、凝胶过滤色谱和反相高效液相色谱的顺序纯化，从脱脂南极磷虾粉（DAKP）蛋白中分离出 DPP-IV 抑制肽 FAGDDAPR 和 LAPPRGSL，这两种肽的 IC 值分别为 349.70±3.66 μM 和 461.14±0.87 μM。采用 LC-MS/MS 法鉴定 FAGDDAPR 和 LAPPRGSL，并用 AutoDock Vina 软件进一步构建 DPP-IV 与这两种肽的分子模型，结果表明 FAGDDAPR 和 LAPPRGSL 的抑制活性主要归因于与 DPP-IV 氨基酸形成强烈的疏水相互作用和氢键。
DAKP 是在生产磷虾油过程中产生的一种经济副产物，含有高质量的蛋白质，但这些产品过去主要用作鱼饲料，利用价值较低。DPP-IV 抑制剂是治疗高血糖过程的有效药物。然而，这些药物可能会引起不良的副作用。因此，开发具有低副作用的新型天然降血糖药物是一种有价值的治疗干预策略。
