Surface Coating Approach to Overcome Mucosal Entrapment of DNA Nanoparticles for Oral Gene Delivery of Glucagon-like Peptide 1

PEI/DNA nanoparticles showed higher diffusivity and transport in the mucus layer of the GI tract and mediated high levels of transfection efficiency in vitro and in vivo. Moreover, these modified nanoparticles demonstrated high levels of GLP-1 expression for more than 24 h in the liver, lungs, and intestine in a T2D murine model after a single dose, as well as controlled blood glucose levels within a normal range for at least 18 h with repeatable therapeutic effects upon multiple dosages. Taken together, this work demonstrates the feasibility of an oral plasmid DNA delivery approach in the treatment of T2D through a facile surface modification to improve the mucus permeability and delivery efficiency of the nanoparticles.