title: In vivo delivery of siRNA to the brain by carbosilane dendrimer.
abstract: Nanotechnology offers a new platform for therapeutic delivery of antiretrovirals to the central nervous system (CNS). Nanoformulated antiretroviral drugs offer multifunctionality, that is, the ability to package multiple diagnostic and therapeutic agents in the same nanocompose, along with the added provisions of site-directed delivery, delivery across the blood-brain-barrier (BBB), and controlled release of therapeutics. We studied the viability of dendrimers and dendriplexes in human primary astrocytes, as well as their uptake by these astrocytes. Functional validation was performed by using specific siRNA against HIV-1 Nef to interfere to HIV-1 infectivity. A high efficiency in Nef silencing, reducing HIV-1 infectivity was observed in astrocytes treated with dendriplexes compared with control or siRandom treated astrocytes. More interestingly, we studied the biodistribution of the second generation of carbosilane dendrimer loaded with FITC (2G-(SNMe3I)11-FITC) in vivo, in BALB/c mice. Dendriplexes were inoculated into BALB/c mice by the retro-orbital venous plexus, and their localization was determined after 1 and 24h post-injection. Dendriplexes were detected inside the brain by a sensitive imaging system of fluorescent imaging in vivo (IVIS Lumina), and by confocal microscopy analysis of sections of OCT-embedded tissues. The 2G-(SNMe3I)11-FITC dendrimer transported efficiently siRNA into the brain, crossing the BBB. Moreover, this dendrimer successfully delivered and transfected siRNA to HIV-infected human primary astrocytes and achieved gene silencing without causing cytotoxicity. These results highlight the potential of this nanoformulation in the treatment of neurological disorders.
authors.affiliation: Laboratorio Inmuno-Biología Molecular, Hospital General Universitario Gregorio Marañón, Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain; Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, Spain.
authors.forename: Ma Jesús
authors.initials: MJ
authors.lastname: Serramía
authors.affiliation: Laboratorio Inmuno-Biología Molecular, Hospital General Universitario Gregorio Marañón, Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain; Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, Spain.
authors.forename: Susana
authors.initials: S
authors.lastname: Álvarez
authors.affiliation: Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, Spain; Departamento Química Orgánica y Química Inorgánica, Universidad Alcalá, Alcalá de Henares, Spain; CIBER-BBN, Spain.
authors.forename: Elena
authors.initials: E
authors.lastname: Fuentes-Paniagua
authors.affiliation: Laboratorio Inmuno-Biología Molecular, Hospital General Universitario Gregorio Marañón, Madrid, Spain; Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, Spain; Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, Spain.
authors.forename: Maria Isabel
authors.initials: MI
authors.lastname: Clemente
authors.affiliation: Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, Spain; Departamento Química Orgánica y Química Inorgánica, Universidad Alcalá, Alcalá de Henares, Spain; CIBER-BBN, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Sánchez-Nieves
authors.affiliation: Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, Spain; Departamento Química Orgánica y Química Inorgánica, Universidad Alcalá, Alcalá de Henares, Spain; CIBER-BBN, Spain.
authors.forename: Rafael
authors.initials: R
authors.lastname: Gómez
authors.affiliation: Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, Spain; Departamento Química Orgánica y Química Inorgánica, Universidad Alcalá, Alcalá de Henares, Spain; CIBER-BBN, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: de la Mata
authors.affiliation: Laboratorio Inmuno-Biología Molecular, Hospital General Universitario Gregorio Marañón, Madrid, Spain; Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, Spain; Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, Spain. Electronic address: mmunoz.hgugm@gmail.com.
authors.forename: Ma Ángeles
authors.initials: MÁ
authors.lastname: Muñoz-Fernández
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000378:metabolism; D002460:Cell Line; D002478:Cells, Cultured; D050091:Dendrimers / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics; D006801:Humans; D008807:Mice, Inbred BALB C; D034741:RNA, Small Interfering / Q000008:administration & dosage* / Q000493:pharmacokinetics; D012821:Silanes / Q000737:chemistry; D054311:nef Gene Products, Human Immunodeficiency Virus / Q000235:genetics
chemical_list: D050091:Dendrimers; D034741:RNA, Small Interfering; D012821:Silanes; C504072:carbosilane; D054311:nef Gene Products, Human Immunodeficiency Virus; C514837:nef protein, Human immunodeficiency virus 1
keywords: Blood–brain-barrier; Brain; Carbosilane dendrimer; Central nervous system; HIV infection; siRNA delivery