title: Synthesis of Electroneutralized Amphiphilic Copolymers with Peptide Dendrons for Intramuscular Gene Delivery.
abstract: Intramuscular gene delivery materials are of great importance in plasmid-based gene therapy system, but there is limited information so far on how to design and synthesize them. A previous study showed that the peptide dendron-based triblock copolymer with its components arranged in a reversed biomembrane architecture could significantly increase intramuscular gene delivery and expression. Herein, we wonder whether copolymers with biomembrane-mimicking arrangement may have similar function on intramuscular gene delivery. Meanwhile, it is of great significance to uncover the influence of electric charge and molecular structure on the function of the copolymers. To address the issues, amphiphilic triblock copolymers arranged in hydrophilic-hydrophobic-hydrophilic structure were constructed despite the paradoxical characteristics and difficulties in synthesizing such hydrophilic but electroneutral molecules. The as-prepared two copolymers, dendronG2(l-lysine-OH)-poly propylene glycol2k(PPG2k)-dendronG2(l-lysine-OH) (rL2PL2) and dendronG3(l-lysine-OH)-PPG2k-dendronG3(l-lysine-OH) (rL3PL3), were in similar structure but had different hydrophilic components and surface charges, thus leading to different capabilities in gene delivery and expression in skeletal muscle. rL2PL2 was more efficient than Pluronic L64 and rL3PL3 when mediating luciferase, β-galactosidase, and fluorescent protein expressions. Furthermore, rL2PL2-mediated growth-hormone-releasing hormone expression could significantly induce mouse body weight increase in the first 21 days after injection. In addition, both rL2PL2 and rL3PL3 showed good in vivo biosafety in local and systemic administration. Altogether, rL2PL2-mediated gene expression in skeletal muscle exhibited applicable potential for gene therapy. The study revealed that the molecular structure and electric charge were critical factors governing the function of the copolymers for intramuscular gene delivery. It can be concluded that, combined with the previous study, both structural arrangements either reverse or similar to the biomembrane are effective in designing such copolymers. It also provides an innovative way in designing and synthesizing new electroneutralized triblock copolymers, which could be used safely and efficiently for intramuscular gene delivery.
authors.affiliation: National Engineering Research Center for Biomaterials, Sichuan University , Chengdu 610064, China.|School of Materials Science and Engineering, Southwest University of Science and Technology , Mianyang 621010, China.
authors.forename: Linyu
authors.initials: L
authors.lastname: Pu
authors.affiliation: National Engineering Research Center for Biomaterials, Sichuan University , Chengdu 610064, China.
authors.forename: Jiali
authors.initials: J
authors.lastname: Wang
authors.affiliation: National Engineering Research Center for Biomaterials, Sichuan University , Chengdu 610064, China.
authors.forename: Na
authors.initials: N
authors.lastname: Li
authors.affiliation: National Engineering Research Center for Biomaterials, Sichuan University , Chengdu 610064, China.
authors.forename: Qiuxia
authors.initials: Q
authors.lastname: Chai
authors.affiliation: School of Pharmacy, University of Navarra , Pamplona 31008, Spain.
authors.forename: Juan M
authors.initials: JM
authors.lastname: Irache
authors.affiliation: National Engineering Research Center for Biomaterials, Sichuan University , Chengdu 610064, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Wang
authors.affiliation: Research Institute in Healthcare Science, Faculty of Science & Engineering, University of Wolverhampton , Wolverhampton WV11SB, United Kingdom.
authors.forename: James Zhenggui
authors.initials: JZ
authors.lastname: Tang
authors.affiliation: National Engineering Research Center for Biomaterials, Sichuan University , Chengdu 610064, China.
authors.forename: Zhongwei
authors.initials: Z
authors.lastname: Gu
mesh_terms: D000818:Animals; D050091:Dendrimers / Q000008:administration & dosage / Q000378:metabolism*; D018014:Gene Transfer Techniques; D051379:Mice; D010455:Peptides / Q000008:administration & dosage / Q000378:metabolism; D011108:Polymers / Q000008:administration & dosage / Q000138:chemical synthesis*
chemical_list: D050091:Dendrimers; D010455:Peptides; D011108:Polymers
keywords: amphiphilic copolymer; biomembrane; electroneutralization; gene expression; gene therapy; intramuscular gene transfer