Optimizing microRNA delivery via albumin-decorated nanostructured lipid carriers.

microRNA-27a is a promising candidate for miRNA mimic therapy to combat obesity, but its clinical application is hindered by enzymatic degradation and low membrane permeability. To address these challenges, we developed cationic nanostructured lipid carriers (cNLCs) via high-pressure homogenization as non-viral carriers for miRNA-27a. However, the formation of a protein corona in biologically-relevant media altered the particle size and surface charge, significantly reducing cellular uptake. To mitigate this issue, we hypothesized that coating miRNA/cNLC complexes with human serum albumin (HSA) will prevent protein corona formation and enhance cellular uptake. The HSA-coated miRNA/cNLC complexes, termed albuplexes, were characterized for particle size, zeta potential, morphology, and stability in various media. The integrity of the HSA coat was assessed using circular dichroism and UV/Vis spectroscopy. We also evaluated the biocompatibility and cellular uptake of albuplexes in 3T3-L1 cells. The biological effects of miRNA-27a on adipocyte development were analyzed through light microscopy and absorbance measurements of Oil-red-O dye in lipid droplets. Results indicated that albuplexes possess favourable physicochemical properties and enhanced stability in serum. Notably, albuplexes were rapidly taken up by 3T3-L cells via endocytosis, although 20 % HSA in the culture medium completely inhibited uptake. Furthermore, albuplexes exhibited an anti-adipogenic effect by reducing the lipid droplet accumulation, suggesting their potential as a therapeutic strategy for miRNA replacement in obesity treatment.