Caco-2细胞模型用于乳源ACE抑制肽LL、LPEW的小肠吸收研究

摘要

Caco-2 cell model was established and verified to analyze the transport capacity of ACE inhibitory peptides LL and LPEW and to explore their transport mechanism across intestinal epithelial cells.Morphology,transepithelial electrical resistance and alkaline phosphatase activity were measured to verify the validity of the Caco-2 cell model.Apparent permeability coefficient (Papp) of LL and LPEW were (275.17 + 8.28) × 10-7 and (5.13 ± 1.49) × 10-7cm/s,respectively in Caco-2 transport experiments,suggesting that LL displayed much better intestinal absorption than LPEW.The transportation route of LL may be endocytosis,as demonstrated by comparing the transport capacity of LL with and without transport inhibitors including the paracellular transport accelerator sodium deoxycholate,the endocytosis inhibitor Wortmannin,and the competitive inhibitor of the peptide transports Gly-Pro.LL had no efflux activity,as suggested by comparing the transport capacity with and without efflux inhibitor including the P-glycoprotein inhibitor verapamil,the multidrug resistance protein inhibitor MK-571,and the ATPase inhibitor sodium azide.In conclusion,LL showed good intestinal absorption.%通过建立并验证Caco-2细胞模型,分析血管紧张素转化酶(angiotensin-Ⅰ converting enzyme,ACE)抑制肽LL、LPEW在小肠中的转运量,研究LL、LPEW的小肠吸收机制.从细胞形态、跨膜电阻和碱性磷酸酶活性3个方面验证Caco-2细胞模型可用性.分析ACE抑制肽LL、LPEW的Caco-2细胞转运量,LL的表观渗透系数(Papp)为(275.17±8.28)×10-7 cm/s,肠道吸收良好;LPEW的Papp为(5.13±1.49)×10-7 cm/s,相比于LL,肠道吸收量较低.加入旁路转运促进剂去氧胆酸钠、内吞抑制剂渥曼青霉素(Wortmannin)、肽转运载体竞争性抑制剂Gly-Pro,对比无抑制剂时LL的转运量,分析得到LL的跨膜转运机制可能为内吞途径.加入ATP能量生成抑制剂叠氮化钠、多药耐药蛋白抑制剂MK-571、P-糖蛋白抑制剂维拉帕米,对比无抑制剂时肽LL的转运量,得出LL没有外排作用,所以LL肠道吸收较好.