Nanomedicines for DNA and interference RNA co-delivery: Combined gene therapy for Fabry disease

Fabry disease (FD) is a multisystemic rare disorder caused by mutations in the GLA gene encoding α-Galactosidase A (α-Gal A) enzyme. The deficiency of this enzyme leads to progressive lysosomal accumulation of glycosphingolipids, especially globotriaosylceramide (Gb3) and lyso-Gb3. Current therapies remain limited in efficacy and do not fully prevent disease progression. In this work, we designed solid lipid nanoparticles incorporating 5 nm gold nanoparticles ("golden SLNs") for the co-delivery of GLA plasmid DNA and siRNA against Gb3 synthase to simultaneously promote α-Gal A production and inhibit Gb3 synthesis, as a dual therapeutic strategy for FD. Nanomedicines were prepared by an optimized electrostatic assembly process, combining both the DNA and siRNA with golden SLNs, the peptide protamine and polysaccharides. They were characterized in terms of size, surface charge and nucleic-acid binding, and evaluated in an endothelial cell model of FD (IMFE-1 cells) to assess intracellular trafficking, α-Gal A expression, Gb3 synthase downregulation, Gb3 reduction, cell viability and hemocompatibility. The golden SLN-based nanomedicines, with a particle size from 200 to 300 nm and positive surface charge, increased α-Gal A activity and reduced Gb3 synthase expression and Gb3 levels for at least 15 days. Protamine and gold nanoparticles played key roles in nucleic-acid condensation and intracellular release, while lipid composition and polysaccharide coating determined efficacy and safety. This study presents the first co-delivery nanomedicine enabling simultaneous gene supplementation and genetic substrate reduction therapy, broadening the therapeutic scope for FD.