Remote loading of alkaloid voacamine in cationic liposomes to improve the reversion of drug resistan phenotype

One of the pharmacological properties of plant alkaloid voacamine is its capability of reverting resistance of tumor cells to doxorubicin, without any intrinsic toxicity. The amine functions of voacamine were exploited to load it with a high efficacy in the internal aqueous compartment of cationic liposomes, formulated with DOPC, a cationic gemini amphiphile and cholesterol, by a transmembrane pH gradient. Experiments on an osteosarcoma resistant cell line, U-2 OS/DX, showed that voacamine delivered by liposomes is more efficient than the free alkaloid to revert resistance of cells to doxorubicin