Highly efficient transfection of rat cortical neurons using carbosilane dendrimers unveils a neuroprotective role for HIF-1alpha in early chemical hypoxia-mediated neurotoxicity.

Departamento de Ciencias Médicas, Unidad Asociada Neurodeath, CSIC-UCLM, Universidad de Castilla-La Mancha, Avda. Almansa, 14, 02006, Albacete, Spain.
Pharmaceutical Research (Impact Factor: 4.74). 03/2009; 26(5):1181-91. DOI: 10.1007/s11095-009-9839-9
Source: PubMed

ABSTRACT To study the effect of a non-viral vector (carbosilane dendrimer) to efficiently deliver small interfering RNA to postmitotic neurons to study the function of hypoxia-inducible factor-1alpha (HIF1-alpha) during chemical hypoxia-mediated neurotoxicity.
Chemical hypoxia was induced in primary rat cortical neurons by exposure to CoCl(2). HIF1-alpha levels were determined by Western Blot and toxicity was evaluated by both MTT and LDH assays. Neurons were incubated with dendriplexes containing anti-HIF1-alpha siRNA and both uptake and HIF1-alpha knockdown efficiency were evaluated.
We report that a non-viral vector (carbosilane dendrimer) can deliver specific siRNA to neurons and selectively block HIF1-alpha synthesis with similar efficiency to that achieved by viral vectors. Using this method, we have found that this transcription factor plays a neuroprotective role during the early phase of chemical hypoxia-mediated neurotoxicity.
This work represents a proof-of-concept for the use of carbosilane dendrimers to deliver specific siRNA to postmitotic neurons to block selected protein synthesis. This indicates that this type of vector is a good alternative to viral vectors to achieve very high transfection levels in neurons. This also suggests that carbosilane dendrimers might be very useful for gene therapy.

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