A Novel niosome gene delivery approach for central nervous system disorders

Introduction Glial cells are part of the nervous tissue where they nourish protect and regulate neuronal function. Therefore, they are ideal vehicle for gene therapy of brain diseases. Niosomes represent a recent safe approach... [ view full abstract ]

Introduction
Glial cells are part of the nervous tissue where they nourish protect and regulate neuronal function. Therefore, they are ideal vehicle for gene therapy of brain diseases. Niosomes represent a recent safe approach for gene delivery purposes. Thus, our aim was to formulate an effective niosome formulation based on the cationic lipid N-[1-(2,3-dioleoyloxy)propyl]-N,N,N-trimethylammonium chloride (DOTMA) to deliver genes to nervous tissue.
Methods
Modified reverse phase evaporation technique was applied to obtain our niosomes. After their physicochemical characterization, niosomes were complexed with pCMS-EGFP reporter plasmid to form nioplexes. Afterwards, nioplexes were used to transfect NT2 cells as well as primary neuronal cells from rat embryonic cortex in vitro followed by studying their uptake and internalization pathways. Finally, Nioplexes were injected to transfect rat cerebral cortex in vivo.
Results
Nioplexes depicted appealing physicochemical properties as gene delivery vehicles. Additionally, they could transfect both NT2 and primary glial cells without compromising cell viability as detected by microscopy and flowcytometry. NT2 showed high uptake of nioplexes (59.6±7.01%), possibly due to their endocytosis by all the tested mechanisms; clathrin-mediated endocytosis (CME), caveolae-mediated endocytosis (CvME) and macropinocytosis. Nevertheless, their co-localization with both CME and lysosomes could explain the relatively lower transfection (up to 16%). When nioplexes were injected into rat cerebral cortex, they had tropism to transfect glial cells.
Conclusion
Thanks to its effectiveness to transfect cortical glial cells in rat brain without the known risks of viral vectors, our niosome vector could be an interesting novel non-viral formulation for gene therapy targeting severe diseases of the brain.