1-2-dielaidoylphosphatidylethanolamine and Liver-Neoplasms

To enhance the solubility of rosiglitazone, rosiglitazone-loaded cationic lipid emulsion was formulated using cationic lipid DOTAP, DOPE, castor oil, tween 20, and tween 80. The formulation parameters in terms of droplet size were optimized focused on the effect of the cationic lipid emulsion composition ratio on drug encapsulating efficiency, in vitro drug release, and cellular uptake of the rosiglitazone-loaded emulsion. Droplet sizes of a blank cationic emulsion and a rosiglitazone-loaded cationic emulsion ranged between 195-230 nm and 210-290 nm, respectively. The encapsulation efficiency of the rosiglitazone-loaded emulsion was more than 90%. The rosiglitazone-loaded cationic emulsion improved in vitro drug release over the drug alone and showed a much higher cellular uptake than rosiglitazone alone. Moreover, drug loading in cationic emulsions increased cellular uptake of rosiglitazone in insulin-resistant HepG2 cells more than the normal HepG2 cells. Taken together, these results indicate that cationic lipid emulsions could be a potential delivery system for rosiglitazone and could enhance its cellular uptake efficiency into target cells.

Topics: Biological Transport; Carcinoma, Hepatocellular; Castor Oil; Cations; Chemistry, Pharmaceutical; Drug Carriers; Drug Stability; Emulsions; Fatty Acids, Monounsaturated; Hep G2 Cells; Humans; Hydrogen-Ion Concentration; Hypoglycemic Agents; Insulin Resistance; Lipids; Liver Neoplasms; Nanoparticles; Particle Size; Phosphatidylethanolamines; Polysorbates; Quaternary Ammonium Compounds; Rosiglitazone; Solubility; Surface-Active Agents; Technology, Pharmaceutical; Thiazolidinediones

The asialoglycoprotein receptor, which is abundantly and near exclusively expressed on hepatocytes, has received much attention in the design of non-viral hepatotropic DNA delivery systems. Thus, asialoglycoproteins and hexopyranosyl ligands have been coupled to DNA-binding cationic polymers and liposomes in the assembly of complexes intended for uptake by liver parenchymal cells. The aim of the study was to construct a hepatocyte-targeted multimodular liposome-based transfecting complex, in which the biotin-streptavidin interaction provides the cohesive force between the ligand asialorosomucoid and the liposome bilayer, and to evaluate its transfection capabilities in the hepatocyte-derived human transformed cell line HepG2. Dibiotinylated asialoorosomucoid was attached to cationic liposomes constructed from 3beta[N-(N',N'-dimethylaminopropane)-carbamoyl] cholesterol (Chol-T):dioleoylphosphatidylethanolamine:biotinylcholesterylformylhydrazide (MSB1) (48:50:2 mole ratio) through streptavidin interposition. Liposome-pGL3 DNA interactions were studied by gel band shift and ethidium displacement assays. The cytotoxicity of assemblies was evaluated in the HepG2 cell line and transfection capabilities determined by measuring the activity of the transgene luciferase. Binding assays showed that all DNA was liposome associated at a DNA (negative):liposome (positive) charge ratio of 1:1. Accommodation of a streptavidin dibiotinylated asialoorosomucoid assembly was achieved at a DNA:liposome:streptavidin dibiotinylated asialoorosomucoid ratio of 1:4:9 (weight basis). Complexes showed optimal transfection activity at this ratio, which was reduced 10-fold by the presence of the competing ligand asialofetuin. The streptavidin-biotin interaction has been applied for the first time to the assembly of hepatocyte-targeted lipoplexes that display asialoorosomucoid and that are well tolerated by a human hepatoma cell line in which transfection is demonstrably achieved by receptor mediation. Favorable size and charge ratio characteristics suggest that this system may be suitable for in vivo application.

Topics: alpha-Fetoproteins; Asialoglycoprotein Receptor; Asialoglycoproteins; Biotin; Biotinylation; Carcinoma, Hepatocellular; Cell Proliferation; Cholesterol; Fetuins; Gene Transfer Techniques; Genes, Reporter; Genetic Therapy; Hep G2 Cells; Humans; Ligands; Liposomes; Liver Neoplasms; Nanostructures; Orosomucoid; Phosphatidylethanolamines; Plasmids; Streptavidin; Transfection; Transgenes

A polylysine partially substituted with polyhydroxyalkanoyl residues and specially with gluconoyl residues was developed in order to increase the transfection efficiency by decreasing the strength of the electrostatic interactions between the DNA and the cationic polymer. Partially gluconoylated polylysine/DNA complexes were more easily dissociated in solution and their transfection efficiency in the presence of chloroquine, evaluated with HepG2 cells, a human hepatocarcinoma line, was higher when 43 +/- 4% of the epsilon-amino groups of polylysine were blocked with gluconoyl residues. Partially gluconoylated polylysine/plasmid complexes were efficient in transfecting different adherent as well as non-adherent cell lines. Partially gluconoylated polylysine formed highly soluble (above 100 micrograms/ml in DNA) complexes with DNA plasmids. In addition, partially gluconoylated polylysine bearing few lactosyl residues increased the transfection efficiency of HepG2 cells which express a galactose-specific membrane lectin.

Topics: Acylation; Amino Acid Sequence; Carcinoma, Hepatocellular; Chloroquine; DNA, Recombinant; Gluconates; Humans; Lactones; Liver Neoplasms; Molecular Sequence Data; Phosphatidylethanolamines; Plasmids; Polylysine; Solubility; Transfection; Tumor Cells, Cultured

Plasmid DNA condensed by polylysine enhanced cationic-liposome-mediated transfection of Hep G2 cells. The luciferase expression plasmid pCMVL was complexed with the polycation poly-L-lysine and mixed with liposomes that contained a 1:1 molar ratio of the cationic lipid 1,2-dioleoyloxy-3-trimethyl-ammoniumpropane, with the neutral phospholipid 1,2-di-(cis-9-octadecenoyl)-sn-glycero-3-phosphoethanolamine. Polylysine enhanced cationic-liposome-mediated transfection of the hepatoblastoma cell line Hep G2 9-fold compared with pCMVL complexed alone with liposomes. The ratio of cationic to anionic charge of the polylysine-pCMVL complexes, and the quantity of cationic liposomes, are important determinants for optimal transfection of Hep G2 cells.

Topics: Cations; Electrophoresis, Agar Gel; Fatty Acids, Monounsaturated; Hepatoblastoma; Humans; Liposomes; Liver Neoplasms; Luciferases; Particle Size; Phosphatidylethanolamines; Plasmids; Polylysine; Quaternary Ammonium Compounds; Transfection; Tumor Cells, Cultured