Nanogels for oligonucleotide delivery to the brain

Area of Science:

• Neuroscience
• Biotechnology
• Materials Science

Background:

• Effective delivery of oligonucleotides (ODN) to the central nervous system is crucial for treating neurodegenerative disorders.
• The blood-brain barrier (BBB) significantly impedes systemic macromolecule transport to the brain.
• Oligonucleotides are rapidly cleared from circulation, limiting their therapeutic potential.

Purpose of the Study:

• To develop and evaluate a novel nanogel system for enhanced oligonucleotide delivery to the brain.
• To investigate the ability of nanogels to facilitate ODN transport across the BBB.
• To assess the in vivo biodistribution and brain accumulation of ODN delivered via nanogels.

Main Methods:

• Synthesis and characterization of cross-linked poly(ethylene glycol)-polyethylenimine nanogels.
• In vitro assessment of ODN encapsulation and transport across bovine brain microvessel endothelial cell monolayers.
• Surface modification of nanogels with targeting molecules (transferrin, insulin).
• In vivo biodistribution studies in a mouse model following intravenous injection.

Main Results:

• Nanogels efficiently encapsulate negatively charged ODN, forming stable complexes <100 nm.
• ODN-loaded nanogels demonstrate effective transport across the BBB in vitro.
• Surface modification with transferrin or insulin further enhances ODN transport efficacy.
• In vivo studies show a 15-fold increase in brain ODN accumulation and reduced liver/spleen uptake compared to free ODN.
• Delivered ODN remains largely intact within the nanogel after transport.

Conclusions:

• The developed nanogel system is a promising platform for systemic delivery of oligonucleotides to the brain.
• Nanogel-mediated delivery overcomes BBB limitations and improves ODN brain targeting.
• This approach holds potential for advancing therapeutic and diagnostic strategies for central nervous system disorders.