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Updated: Jul 5, 2026

Methods to Study Epithelial Transport Protein Function and Expression in Native Intestine and Caco-2 Cells Grown in 3D
Published on: March 16, 2017
Transport of Val-Leu-Pro-Val-Pro in human intestinal epithelial (Caco-2) cell monolayers
Lin Lei1, Haiyan Sun, Dong Liu
1Department of Applied Biotechnology, Shenzhen Polytechnic, Shenzhen, Guangdong, People's Republic of China.
Abstract:
Angiotensin converting enzyme (ACE) inhibitory peptides are biologically active peptides that play a very important role in blood pressure regulation. In previous experiments, we obtained an ACE inhibitory peptide Val-Leu-Pro-Val-Pro (VLPVP) by DNA recombinant technology. The purpose of this study was to examine the bidirectional transport of VLPVP by using the human intestinal Caco-2 monolayers. The permeability coefficient ( P app) values of VLPVP over 4-8 mmol/L ranged from 7.44 x 10(-8) to 1.35 x 10(-6) cm/s for apical (AP) to basolateral (BL) transport, while the P app values for BL to AP flux were significantly lower than those for the AP to BL flux, with efflux ratio values of 0.74-0.13 over 4-8 mM. Preincubation of the paracellular transport enhancer (sodium deoxycholate), the inhibitor of multidrug resistant protein (MK-571), or sodium azide stimulated efflux of VLPVP significantly ( p < 0.01); these results indicate that the transport of VLPVP across Caco-2 monolayers was involved in paracellular diffusion and MRP2 transport.
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