title: Delivery of cationic polymer-siRNA nanoparticles for gene therapies in neural regeneration.
abstract: The therapeutic applications of neural stem cells (NSCs) have potential to promote recovery in many obstinate diseases in central nervous system. Regulation of certain gene expressions using siRNA may have significant influence on the fate of NSC. To achieve the optimum gene silencing effect of siRNA, non-viral vector polyethylene glycol-polyethyleneimine (PEG-PEI) was investigated in the delivery of siRNA to NSCs. The characteristics of PEG-PEI/siRNA polyplexes were detected by scanning electron microscopy (SEM). The effects of nanoparticles on cell viability were measured via CCK-8 assay. In addition, the transfection efficiency was evaluated by fluorescence microscope and flow cytometry, and real-time PCR and Western Blot were employed to detect the gene inhibition effect of siRNA delivered by PEG-PEI. The SEM micrographs showed that PEG-PEI could condense siRNA to form diffuse and spherical nanoparticles. The cytotoxicity of PEG-PEI/siRNA nanocomplexes (N/P=15) was significantly lower when compared with that of Lipofectamine 2000/siRNA (P<0.05). Moreover, the highest transfection efficiency of PEG-PEI/siRNA nanoparticles was obtained at an N/P ratio of 15, which was better than that achieved in the transfection using Lipofectamine 2000 (P<0.05). Finally, the gene knockdown effect of PEG-PEI/siRNA nanoparticles was verified at the levels of mRNA and protein. These results suggest that PEG-PEI may potentially be used as a siRNA delivery vector for neural regeneration therapy.
authors.affiliation: Department of Neurology, Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University, No. 107, West Yanjiang Road, Guangzhou 510120, People's Republic of China.
authors.forename: Yanran
authors.initials: Y
authors.lastname: Liang
authors.forename: Zhonglin
authors.initials: Z
authors.lastname: Liu
authors.forename: Xintao
authors.initials: X
authors.lastname: Shuai
authors.forename: Weiwei
authors.initials: W
authors.lastname: Wang
authors.forename: Jun
authors.initials: J
authors.lastname: Liu
authors.forename: Wei
authors.initials: W
authors.lastname: Bi
authors.forename: Chuanming
authors.initials: C
authors.lastname: Wang
authors.forename: Xiuna
authors.initials: X
authors.lastname: Jing
authors.forename: Yunyun
authors.initials: Y
authors.lastname: Liu
authors.forename: Enxiang
authors.initials: E
authors.lastname: Tao
mesh_terms: D000818:Animals; D058851:GPI-Linked Proteins / Q000235:genetics; D055785:Gene Knockdown Techniques; D015316:Genetic Therapy / Q000379:methods*; D051379:Mice; D009185:Myelin Proteins / Q000235:genetics; D053758:Nanoparticles / Q000008:administration & dosage* / Q000737:chemistry; D009416:Nerve Regeneration; D009474:Neurons / Q000502:physiology*; D000070816:Nogo Receptor 1; D011092:Polyethylene Glycols / Q000737:chemistry; D011094:Polyethyleneimine / Q000031:analogs & derivatives / Q000737:chemistry; D034741:RNA, Small Interfering / Q000008:administration & dosage* / Q000737:chemistry; D011956:Receptors, Cell Surface / Q000235:genetics; D014162:Transfection
chemical_list: D058851:GPI-Linked Proteins; D009185:Myelin Proteins; D000070816:Nogo Receptor 1; D034741:RNA, Small Interfering; D011956:Receptors, Cell Surface; C419790:Rtn4r protein, mouse; C544016:poly(ethylene glycol)-co-poly(ethyleneimine); D011092:Polyethylene Glycols; D011094:Polyethyleneimine