RVG-Peptide-Linked Trimethylated Chitosan for Delivery of siRNA to the Brain

Abstract

In this work, a peptide derived from the rabies virus glycoprotein (RVG) was linked to siRNA/trimethylated chitosan (TMC) complexes through bifunctional PEG for efficient brain-targeted delivery of siRNA. The physiochemical properties of the complexes, such as siRNA complexing ability, size and ζ potential, morphology, serum stability, and cytotoxicity, were investigated prior to studying the cellular uptake, in vitro gene silencing efficiency, and in vivo biodistribution. The RVG-peptide-linked siRNA/TMC-PEG complexes showed increased serum stability, negligible cytotoxicity, and higher cellular uptake than the unmodified siRNA/TMC-mPEG complexes in acetylcholine receptor positive Neuro2a cells. The potent knockdown of BACE1, a therapeutic target in Alzheimer's disease, demonstrated the gene silencing efficiency. In vivo imaging analysis showed significant accumulation of Cy5-siRNA in the isolated brain of mice injected with RVG-peptide-linked complexes. Therefore, the RVG-peptide-linked TMC-PEG developed in this study can be used as a potential carrier for delivery of siRNA to the brain.

A method for concentrating lipid peptide DNA and siRNA nanocomplexes that retains their structure and transfection efficiency

“…30,[33][34][35] In addition, the nanoparticles used here are formed by self-assembly, whereas others use conjugation of the peptide by covalent bonds on the surface of the delivery vectors. 36,37 However, this does not imply that our RVG …”

“…No silencing of mouse BACE1 was detected following intravenous injections ( Figure 5D), unlike other reports that showed silencing even when the RVG/siRNA were delivered by intravenous injections. 30,[33][34][35] Other recent research showed nanoparticle deposition in the brain, but it did not examine the silencing effects there, 36 or it assessed increased enzymatic activity following β-galactosidase administration. 37 The lack of silencing following the intravenous administration of RVG-containing nanoparticles could be due to differences in both the amount of dose and the number of doses delivered, as we used a single 16 μg or 50 μg dose, whereas others use 50-150 μg for up to four doses.…”

3D in vitro modeling of the central nervous system

“…Hydrogels can be of natural or synthetic origin and include agarose (Balgude et al, 2001; Bellamkonda et al, 1995a, 1995b; Cullen et al, 2007a; Dillon et al, 1998; O'Connor et al, 2001), collagen type I (Coates and Nathan, 1987; Coates et al, 1992; Krewson et al, 1994; O'Connor et al, 2000a; O'Shaughnessy et al, 2003), hyaluronic acid (Brännvall et al, 2007, 2007; Hou et al, 2006; Pedron et al, 2013; Tian et al, 2005), N -(2-hydroxypropyl) methacrylamide (HPMA) (Woerly et al, 1990, 1991), poly(ethylene glycol) (PEG) (Pedron et al, 2013; Wang et al, 2014; Zustiak et al, 2013), chitosan (Gao et al, 2014; Leipzig et al, 2011; McKay et al, 2014), alginate (Frampton et al, 2011; Kuo and Chang, 2013; Matyash et al, 2012; Mosahebi et al, 2003), silk fibroin (Benfenati et al, 2010, 2012; Hopkins et al, 2013; Hu et al, 2013; Kim et al, 2010; Tien et al, 2013; Zhang et al, 2012) and methylcellulose (Stabenfeldt and LaPlaca, 2011; Tate et al, 2001), Table 2 .…”

Non-Viral Nucleic Acid Delivery Strategies to the Central Nervous System

“…Upon systemic intravenous administration, these complexes were able to transvascularly deliver siRNA to the brain through clathrin- and caveolae-mediated endocytosis by endothelial cells, which lead to extended lives of encephalitic mice. The RVG peptide can also modulate the accumulation of larger vehicles and has delivered macro-structures such as PAMAM dendrimers (Liu et al, 2009), liposomes (Pulford et al, 2010), chitosan nanoparticles (Gao et al, 2014), poly(mannitol- co -PEI) complexes (Park et al, 2015) and exosomes (Alvarez-Erviti et al, 2011) across the BBB and into the brain parenchyma. Other targeting agents have included: angiopep, a peptide that binds to low-density lipoprotein receptor-related protein-1 (Ke et al, 2009); lactoferrin, an iron-binding protein of the transferrin family (Huang et al, 2008, 2010); leptin, a peptide that binds to leptin receptor in different parts of the brain (Liu et al, 2010); chlorotoxin, a scorpion-derived venom that is a specific marker for gliomas (Costa et al, 2013); TGN peptide, a BBB targeting peptide isolated by phage display (Qian et al, 2013); and LIMK2 NoLs peptide, a nucleolar translocation signal sequence derived from the LIM Kinase 2 protein (Yao et al, 2015).…”