查看更多>>摘要：The electrostatic interactions between cationic poly(amidoamine) (PAMAM) dendrimers of different generations, G3, G4, and G6, with net anionic model biomembranes have been predicted by adopting an analytical model based on two dissimilar soft spheres. The influence of bilayer surface charge density, ionic strength, pH, temperature, membrane softness (modeled as changes in bilayer thickness), and dendrimer generation on the attractive interaction was investigated. The attraction was found to decrease with increasing salt concentration, dendrimer charge, and thickness (or softness) of the membrane. On the other hand, the attraction increased with the surface charge density of the membrane, and the size of dendrimer generation. In fact, the attraction was found to be much larger for large generations, like G6 dendrimer that have a higher charge, than it is with small ones like G3 and G4 dendrimers. These results have implications for the use of PAMAM dendrimers as potential gene transfection vectors.
查看更多>>摘要：Hepcidin, a key regulator of iron homeostasis, has been implicated in the pathogenesis of various iron-related diseases. Although small interfering RNA (siRNA) are potent to modulate the expression of hepcidin, their bioavailability remains a major issue. The beta-galactopyranoside-conjugated liposomes (GAL-liposome) targeting liver synthesized hepcidin were prepared by thin lipid film hydration method to encapsulate siRNA and the conjugation of beta-galactopyranoside to the lipid nanocarrier was achieved by covalent chemistry. The prepared siRNA loaded GAL-lip were spherical with around 50 nm radius in size as observed by HR-TEM. The zeta potential and polydispersity index of the prepared liposomes were -19.9 +/- 0.96 mV and 0.44 +/- 0.05, respectively. The encapsulation efficiency as determined by dialysis bag method was around 91.76 +/- 1.74%. The cell viability and cellular uptake analysis was examined in HepG2 cells by MTT assay and flow cytometry, respectively. The stability and cumulative release of siRNA was also assessed. The hepcidin mRNA expression on administration of siRNA loaded GAL-lip was determined in HepG2 cells and in lipopolysaccharide-induced mice model followed by examining itsin vivo biodistribution by fluorescence microscopy. The results suggested thatsiRNA loaded GAL-lip reduced the hepcidin levels, thus, highlighting a novel ligand conjugated ionizable lipid-based nanocarrier for inducing RNA interference.
NSTL
Elsevier