Deoxycholic acid-polymer conjugates for gene delivery to ischemic stroke

Abstract

The deoxycholic acid (DA), which is a class of bile acids, is composed of hydrophilic groups and hydrophobic groups. In order to increase the transfection efficiency and to decrease the cytotoxicity, DA was conjugated to polymers such as low molecular weight PEI (1.8 kDa). In this study, DA3(DA/PEI molar feed ratio 3:1) was used as a gene carrier. In a gel retardation assay and heparin competition assay, DA3 retarded plasmid DNA (pCI) completely at 2:1 weight ratio (DA3:pCI) and released pCI at 2:1 weight ratio (heparin:pCI). In a transfection assay, DA3 had higher transfection efficiency than PEI25k and lipofectamine. In addition, the expression of the heme oxygenase 1 gene with DA3 was also higher compared to other gene carriers. In a MTT assay, DA3 was less cytotoxic than other carriers in neuro2A cells. Therefore, DA3 may prove to be useful as gene delivery carrier for ischemic stroke.