Stearylamine Liposome as an Anti-Parasitic Agent

Abstract

The uncontrolled increasing clinical resistance to the current anti-parasitic drugs towards important protozoan parasites (Plasmodium, Leishmania, Trypanosoma and Toxoplasma) has stimulated the search for novel and safe therapeutic agents at affordable prices for countries in which these parasites are endemic. For the past few decades, the criticality of the cationic lipid stearylamine (SA) in liposomes has been explored in these human parasites. Previously, SA was incorporated in the liposomal formulation to impart a net positive charge for enhanced cellular uptake. However, the discovery of SA in liposomes alone elicits a strong anti-parasitic activity with immunomodulatory potential. Additionally, the SA liposome possesses a significant inhibitory potential on multiple life stages of the parasite cycle and delivers an equal effect on both drug-sensitive and resistant parasites. Moreover, the delivery of standard anti-parasitic drugs using SA liposome vesicles has enhanced the efficacy of drugs due to the synergistic impacts without causing any apparent toxicity on the host cells. In addition, the delivery of antigens as vaccine candidates using SA liposomes elicits a pronounced immune response in clearing the infection compared to other cationic lipids and SA-free liposomes. Nonetheless, SA liposome mediates its anti-parasitic activity by targeting the negatively charged phosphatidylserine-exposed infected host cell surface or by interaction with negatively charged sialic acid of free-living parasites. Overall, SA liposome confers its protection by acting as a chemotherapeutic agent with immunomodulatory activity. Therefore, a broadly acting anti-parasitic agent (SA liposome) is promising in tackling the deadly parasitic infections in endemic regions and warrants further clinical investigations.