dioleoyl-phosphatidylethanolamine and Mucopolysaccharidosis-I

This study demonstrates the nasal administration (NA) of nanoemulsions complexed with the plasmid encoding for IDUA protein (pIDUA) as an attempt to reach the brain aiming at MPS I gene therapy.. Formulations composed of DOPE, DOTAP, MCT (NE), and DSPE-PEG (NE-PEG) were prepared by high-pressure homogenization, and assessed in vitro on human fibroblasts from MPS I patients and in vivo on MPS I mice for IDUA production and gene expression.. The physicochemical results showed that the presence of DSPE-PEG in the formulations led to smaller and more stable droplets even when submitted to dilution in simulated nasal medium (SNM). In vitro assays showed that pIDUA/NE-PEG complexes were internalized by cells, and led to a 5% significant increase in IDUA activity, besides promoting a two-fold increase in IDUA expression. The NA of pIDUA/NE-PEG complexes to MPS I mice demonstrated the ability to reach the brain, promoting increased IDUA activity and expression in this tissue, as well as in kidney and spleen tissues after treatment. An increase in serum IL-6 was observed after treatment, although with no signs of tissue inflammatory infiltrate according to histopathology and CD68 assessments.. These findings demonstrated that pIDUA/NE-PEG complexes could efficiently increase IDUA activity in vitro and in vivo after NA, and represent a potential treatment for the neurological impairment present in MPS I patients.

Topics: Administration, Intranasal; Animals; Brain; Cations; Cell Survival; Emulsions; Fatty Acids, Monounsaturated; Fibroblasts; Gene Transfer Techniques; Genetic Therapy; Genetic Vectors; Humans; Iduronidase; Mice; Mice, Inbred C57BL; Mucopolysaccharidosis I; Nanoparticles; Nucleic Acids; Particle Size; Phosphatidylethanolamines; Polyethylene Glycols; Quaternary Ammonium Compounds; Spleen; Transfection

Mucopolysaccharidosis type I (MPS I) is an autosomal disease caused by alpha-L-iduronidase deficiency. This study proposed the use of cationic nanoemulsions as non-viral vectors for a plasmid (pIDUA) containing the gene that codes for alpha-L-iduronidase. Nanoemulsions composed of medium chain triglycerides (MCT)/1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE)/1,2-dioleoyl-sn-glycero-3-trimethylammonium propane (DOTAP)/1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[amino(polyethylene glycol)-2000] (DSPE-PEG) were prepared by high pressure homogenization. Formulations were prepared by the adsorption or encapsulation of preformed pIDUA-DOTAP complexes into the oil core of nanoemulsions at different charge ratios. pIDUA complexed was protected from enzymatic degradation by DNase I. The physicochemical characteristics of complexes in protein-containing medium were mainly influenced by the presence of DSPE-PEG. Bragg reflections corresponding to a lamellar organization were identified for blank formulations by energy dispersive X-ray diffraction, which could not be detected after pIDUA complexation. The intravenous injection of these formulations in MPS I knockout mice led to a significant increase in IDUA activity (fluorescence assay) and expression (RT-qPCR) in different organs, especially the lungs and liver. These findings were more significant for formulations prepared at higher charge ratios (+4/-), suggesting a correlation between charge ratio and transfection efficiency. The present preclinical results demonstrated that these nanocomplexes represent a potential therapeutic option for the treatment of MPS I.

Topics: Animals; Disease Models, Animal; Emulsions; Fatty Acids, Monounsaturated; Gene Expression; Genetic Therapy; Humans; Iduronidase; Kidney; Liver; Lung; Male; Mice, Inbred C57BL; Mice, Knockout; Mucopolysaccharidosis I; Nanostructures; Phosphatidylethanolamines; Plasmids; Polyethylene Glycols; Quaternary Ammonium Compounds; Spleen; Transfection; Triglycerides