[Plasma lipoproteins as drug carriers. Effect of phospholipid formulations]

The extensive development of nanotechnologies in the last two decades has brought about new understanding of plasma lipoproteins (LP) as natural drug nanocarriers that escape interaction with immune and reticuloendothelial systems. Drugs bound to LP (especially LDL) can more actively penetrate into cells of many cancer and inflammation tissues with enhanced expression or/and dysregulation of B,E receptors or possibly scavenger SR-BI receptors. Relevant studies are focused on the development of new dosage forms by conjugating lipophilic drugs either with isolated plasma LP or with their model formulations, such as nanoemulsions, mimetics, lipid nanospheres, etc. Some authors include in these particles serum or recombinant apoproteins, peptides, and modified polymer products. As shown recently, protein-free lipid nanoemulsions in plasma take up free apoA and apoE. Complexes with various LP also form after direct administration of lypophilic drugs into blood especially those enclosed in phospholipid formulations, e.g. liposomes. Results of evaluation of some lipophilic dugs (mainly cytostatics, amphotericin B, cyclosporine A, etc.) are discussed. Original data are presented on the influence of phospholipid formulations on the distribution of doxorubicin and indomethacin between LP classes after in vitro incubation in plasma. On the whole, the review illustrates the importance of research on LP and phospholi pid forms as drug nanocarriers to be used to enhance effect of therapy.