The stimulation of GLP-1 secretion and delivery of GLP-1 agonists via nanostructured lipid carriers†
Neha Shrestha,Oriane Bouttefeux,Kevin Vanvarenberg,Patrik Lundquist,Juan Cunarro,Sulay Tovar,Georgiy Khodus,Ellen Andersson,Åsa V. Keita,Carlos Gonzalez Dieguez,Per Artursson,Véronique Préat,Ana Beloqui
Nanoscale Pub Date : 11/28/2017 00:00:00 , DOI:10.1039/C7NR07736J
Abstract

Nanoparticulate based drug delivery systems have been extensively studied to efficiently encapsulate and deliver peptides orally. However, most of the existing data mainly focus on the nanoparticles as a drug carrier, but the ability of nanoparticles having a biological effect has not been exploited. Herein, we hypothesize that nanostructured lipid carriers (NLCs) could activate the endogenous glucagon-like peptide-1 (GLP-1) secretion and also act as oral delivery systems for GLP-1 analogs (exenatide and liraglutide). NLCs effectively encapsulated the peptides, the majority of which were only released under the intestinal conditions. NLCs, with and without peptide encapsulation, showed effective induction of GLP-1 secretion in vitro from the enteroendocrinal L-cells (GLUTag). NLCs also showed a 2.9-fold increase in the permeability of exenatide across the intestinal cell monolayer. The intestinal administration of the exenatide and liraglutide loaded NLCs did not demonstrate any glucose lowering effect on normal mice. Further, ex vivo studies depicted that the NLCs mainly adhered to the mucus layer. In conclusion, this study demonstrates that NLCs need further optimization to overcome the mucosal barrier in the intestine; nonetheless, this study also presents a promising strategy to use a dual-action drug delivery nanosystem which synergizes its own biological effect and that of the encapsulated drug molecule.

Graphical abstract: The stimulation of GLP-1 secretion and delivery of GLP-1 agonists via nanostructured lipid carriers