Targeted delivery of antisense drugs is a promising technology which can provide a platform for the development of highly effective therapeuticals against a broad range of diseases. Insufficient stability of RNA in biological media coupled with hydrophilicity that prevents the molecule from penetrating cell membranes considerably limit RNA application in clinical practice. The aim of this work was to design a system for antisense drug delivery to liver hepatocytes using lipidoid magnetic nanoparticles (LNP). Nanocubes (NC) with average sizes of 16 and 27 nm were synthesized through decomposition of iron (III) oleate under high temperature conditions and functionalized with a cationic lipidoid С12-200. Magnetic NC demonstrated good MR-contrasting properties. Biodistribution of LNP was studied in vivo in BALB/c mice using the MR scanner. Additionally, liver sections obtained from the mice were subjected to histological examination. Nanoparticles of smaller size did not have a cytotoxic effect on HepG2 and Huh7 cell lines, whereas for larger NC, IC50 was 21.5 μg/ml and 126 μg/ml for HepG2 and Huh7 cells, respectively. Smaller particles tended to accumulate in hepatocytes. Bigger NC mainly accumulated in the spleen but also ended up in liver macrophages. This fact can be explained by a bigger hydrodynamic size of nanoparticles with a bigger magnetic core. Particles with smaller cores are a more effective platform for the delivery of antisense drugs to hepatocytes.
VIEWS 3978
Aluminum phthalocyanine nanoparticles (NP AlPc) possess the features that make them a promising photosensitizer. In particular, AlPc NPs do not fluoresce in free nanoform, fluoresce weakly in normal tissue, strongly in tumors and very strongly in macrophages. Also, such particles fluoresce and become phototoxic when contacting certain biocomponents. The type of biocomponents that bind to AlPc NPS defines intensity, lifetime, and spectral distribution of the fluorescence. This study aimed to investigate the peculiarities of nanophotosensitizer capturing in 3D models of cell cultures. The data obtained demonstrate that AlPc NPs are captured by cells inside the spheroid in the course of the first hour, as the fluorescent signal's growth shows. Having analyzed the fluctuations of the fluorescence signal of AlPc NPs inside a spheroid, we have also discovered that the cellular 3D models are heterogeneous. Laser irradiation (two-photon excitation at λ = 780/390 nm) resulted in photobleaching of fluorescence, which is probably associated with AlPc NP deactivation. Thus, the created model comprised of a 3D cell culture and AlPc NPs provides a better insight into metabolic processes in cells than monolayer 2D cell cultures. Besides, the model allows to evaluate the photodynamic effect depending on phenotypic properties of various areas in the heterogeneous 3D-structure.
VIEWS 3822