One‐Pot Synthesis of PEGylated Lipoplexes to Facilitate Mucosal Permeation for Oral Insulin Gene Delivery

Abstract

AbstractOral nucleic acid therapy for transgene expressions of insulin in vivo is an emerging strategy in treating type I diabetes (T1D) to address poor patient compliance for daily insulin injections. However, this strategy to achieve high delivery efficiency is impeded by biological barriers including gastrointestinal trafficking, enzymatic degradation, mucosal transport, etc. This article addresses the mucosal transport barrier by adopting a hydrophilic and neutral surface onto cationic lipid/DNA nanoparticles to reduce the obstacle of permeation through the mucus. A facile one‐pot method to coat the PEG layer on a (2,3‐dioleoyloxy‐propyl)‐trimethylammonium (DOTAP)/DNA nanocomplex for expressing insulin is presented. A kinetically controlled mixing technique, namely flash nanocomplexation (FNC), is used to rapidly mix 1,2‐dimyristoyl‐rac‐glycero‐3‐methoxy poly(ethylene glycol)‐2000 (DMG‐PEG) and DOTAP with plasmid DNA. The produced uniform nanoparticles (60 ± 2.1 nm) with a PEG surface demonstrates enhanced transportation in the mucus layer of the GI tract. A systemic transgene expression is confirmed, and the expressed insulin maintains the blood glucose level of streptozotocin (STZ)‐induced T1D mice within the normal range (5–10 mmol L−1) for 24 h following oral gavage and shows repetitive therapeutic effects by multiple doses. This shows the feasibility for fast translation of DMG‐PEG/DOTAP‐DNA nanoparticles in T1D treatment via oral delivery.