Antileishmanial activity and immune modulatory effects of benzoxonium chloride and its entrapped forms in niosome on Leishmania tropica

Benzoxonium chloride is an anti-infective agent that is used as anti-septic drugs for disinfection of the mucus membrane, skin surface and anti-bacterial, and it is also found to be effective against cutaneous leishmaniasis. The present study aims to evaluate the leishmanicidal activity of benzoxonium chloride and niosomal forms against Leishmania tropica stages. Benzoxonium chloride niosomes were prepared by the thin film hydration method and evaluated for morphology, particle size and release study and encapsulation efficiency. This study measured the cytotoxicity, leishmanicidal activity against promastigote and intra macrophage amastigote, apoptosis, and mRNA transcripts by quantitative real time PCR (qPCR) of free solution and niosomal-encapsulated benzoxonium chloride. Span/Tween 60 niosomal formulation of benzoxonium chloride showed superior physical stability and high encapsulation efficiency (96%) than the other forms. Release from the formulations showed that the Span/Tween 60 containing drug had a milder gradient so that 10% of the drug was not released after 4 h. The benzoxonium chloride and niosomal forms inhibited the in vitro growth of promastigote and amastigote forms of L. tropica after 48 h of incubation and represented IC(50) values of 90.7 ± 2.7 and 25.4 ± 0.6 μg/ mL, respectively. The rate of apoptosis in niosomal formulations was approximately equal to the positive control (meglumine antimoniate) at the same concentration. Also, an increase in the concentration of this drug reduced the expression of IL-10, but increased the expression of IL-12. The niosomal formulations provided improved anti-leishmanial activities of benzoxonium chloride and played an immunomodulatory role as the mode of action in the treatment of anthroponotic CL.