Abstract
Background: The application of gene therapy for treating neurological disorders, including brain cancer, Parkinson's, and Alzheimer's disease, is significantly limited by the current shortage of gene vectors that can effectively cross the blood-brain barrier (BBB) following intravenous administration. Recent studies demonstrated that angiopep-2 can enhance the delivery of therapeutic agents across the BBB through receptor-mediated endocytosis. This study therefore explores the potential of angiopep-2-conjugated generation-3 diaminobutyric polypropylenimine (DAB) dendrimer (DAB-Ang) as nanocarrier for brain-targeted gene delivery.
Methods: Angiopep-2 was conjugated to DAB dendrimer and evaluated in terms of DNA condensation ability, particle size, surface charge, and structural morphology. The cellular uptake was studied in vitro using bEnd.3 brain endothelial cells, and the in vivo efficacy of DAB-Ang dendriplexes for brain gene expression was evaluated in BALB/c mice following intravenous administration.
Results: DAB-Ang dendrimer successfully condensed up to 90% of DNA, forming stable spherical dendriplexes with sizes under 240 nm and positive zeta potentials. In vitro, DAB-Ang dendriplex achieved a 9-fold higher cellular uptake in brain endothelial cells in comparison to the unmodified complex, predominantly through clathrin-mediated endocytosis and macropinocytosis. In vivo studies showed significantly increased gene expression in the brain following DAB-Ang dendriplex treatment, achieving 1.8-fold and 3.2-fold higher expression in comparison to DAB dendriplex and naked DNA, respectively, with minimal off-target effects.
Conclusion: Angiopep-2-conjugated DAB dendrimer demonstrated high specificity and efficacy in facilitating gene delivery to the brain, offering a promising platform for therapeutic applications in neurological disorders.
Methods: Angiopep-2 was conjugated to DAB dendrimer and evaluated in terms of DNA condensation ability, particle size, surface charge, and structural morphology. The cellular uptake was studied in vitro using bEnd.3 brain endothelial cells, and the in vivo efficacy of DAB-Ang dendriplexes for brain gene expression was evaluated in BALB/c mice following intravenous administration.
Results: DAB-Ang dendrimer successfully condensed up to 90% of DNA, forming stable spherical dendriplexes with sizes under 240 nm and positive zeta potentials. In vitro, DAB-Ang dendriplex achieved a 9-fold higher cellular uptake in brain endothelial cells in comparison to the unmodified complex, predominantly through clathrin-mediated endocytosis and macropinocytosis. In vivo studies showed significantly increased gene expression in the brain following DAB-Ang dendriplex treatment, achieving 1.8-fold and 3.2-fold higher expression in comparison to DAB dendriplex and naked DNA, respectively, with minimal off-target effects.
Conclusion: Angiopep-2-conjugated DAB dendrimer demonstrated high specificity and efficacy in facilitating gene delivery to the brain, offering a promising platform for therapeutic applications in neurological disorders.
| Original language | English |
|---|---|
| Pages (from-to) | 11569—11591 |
| Number of pages | 23 |
| Journal | International Journal of Nanomedicine |
| Volume | 20 |
| Issue number | 20 |
| DOIs | |
| Publication status | Published - 20 Sept 2025 |
Funding
This work was financially supported by a PhD studentship awarded by Kuwait University (Kuwait) to Hawraa Ali-Jerman, by a Global Research Scholarship from the University of Strathclyde to Zainab Al-Quraishi, and a PhD studentship from the Libyan Government (Libya) to Khadeejah Maeyouf. Sukrut Somani was funded by a research grant from The Dunhill Medical Trust [grant number R463/0216]. Shuzo Sakata was supported by Medical Research Council (MR/V033964/1 and MR/Y004051/1).
Keywords
- dendrimer
- angiopep
- brain delivery
- gene expression
- blood-brain barrier
