Preparation and characterization of bortezomib loaded targeted lipid nanoparticles and evaluation of their effects on liver cancer cell line

Abstract

Introduction: Research on targeted drug delivery systems using nanoparticles for the treatment of hepatocellular carcinoma (HCC), the most common type of liver cancer, has attracted the attention of researchers. Asialoglycoprotein receptors (ASGPRs), which are highly expressed on liver cancer cells (HepG2), have been investigated for targeted drug delivery to the liver and treatment of HCC by researchers.Objective: Solid lipid nanoparticles modified with N-stearyl lactobionic amide (N-SALB), as targeted ligands for ASGPR receptors, were prepared and their selective accumulation in HepG2 cells was evaluated and compared in in vitro and in vivo conditions.Methodology: Initially, lactobionic acid was converted to its cyclic ester form (lactobiono-1,5-lactone). Then, stearyl amine and lactobiono-1,5-lactone were reacted to obtain N-SALB. The structure of N-SALB and the solid lipid nanoparticles modified with it were examined. Cellular uptake, cellular toxicity, and apoptosis of the formulations on HepG2 cells were evaluated using flow cytometry, MTT assay, and Annexin V-FITC/PI staining, respectively. Finally, studies were conducted in HepG2 bearing nude mice by injecting the prepared formulations for in vivo evaluation.Conclusion: The targeted solid lipid nanoparticles loaded with bortezomib had an average particle size of 116 nm, a polydispercity index (PDI) of 0.210, and a zeta potential of -13.8 mV. Transmission electron microscopy confirmed their spherical shape. The encapsulation efficiency was 84%, and the drug loading capacity was 1.16%. Release studies conducted at pH 7.4 revealed that 80% of bortezomib was released within the first 5 hours from its solution, while 50% of bortezomib loaded inside solid lipid nanoparticles (SLNs) was released gradually over a period of 72 hours. In HepG2 cells, flow cytometry analysis demonstrated that the intracellular uptake of targeted nanoparticles was significantly higher than that of non-targeted nanoparticles. Cytotoxicity studies using the MTT test indicated that loading bortezomib inside nanoparticles significantly enhanced its cytotoxicity in targeted nanoparticles compared to non-targeted nanoparticles. Specifically, at a concentration of 25 nM, the cytotoxicity of bortezomib loaded in targeted nanoparticles and non-targeted nanoparticles was approximately 35% and 50% respectively in the HepG2 cell line. The percentage of apoptosis for targeted and non-targeted nanoparticles at a bortezomib concentration of 6 nM were 42.2% and 8.70% respectively.