ABSTRACT
Objective: To explore the antileishmanial effect of tioxolone and its niosomal form against Leishmania tropica. Methods: Tioxolone niosomes were prepared by the hydration method and were evaluated for morphology, size, release study, and encapsulation efficiency. The cytotoxicity of tioxolone and its niosomal form was measured by MTT assay, leishmanicidal activity against promastigote and amastigote by MTT assay, apoptosis by flow cytometry, IL-12, IL-10 and metacaspase gene expression levels by q-PCR. Results: Span/Tween 40 and Span/Tween 60 niosomes had good physical stability as depicted in their size distribution curves and high encapsulation efficiency (>99%). The release profile of the entrapped compounds showed Fickian's model of tioxolone delivery based on diffusion through lipid bilayers. With the IC50 value for amastigote as (24.5±2.1) μg/mL and selectivity index as 10.5, the Span/Tween 60 niosome (NT2) had a superior effect to other drugs. The CC50 value and IC50 of promastigote value for NT2 were (257.5±24.5) μg/mL and (164.8±20.6) μg/ mL, respectively. The flow cytometric analysis showed that tioxolone and niosomal forms induced apoptosis of Leishmania tropica promastigotes in a dose-dependent manner. NT2 increased the expression level of IL-12 and metacaspase genes and decreased the expression level of the IL-10 gene. Conclusions: Niosomes of tioxolone play an immunomodulatory role in increasing Th1 cytokine profile and inhibiting the Th2 cytokine profile. It could be used for treatment of anthroponotic cutaneous leishmaniasis.
ABSTRACT
Objective: To explore the antileishmanial effect of tioxolone and its niosomal form against Leishmania tropica. Methods: Tioxolone niosomes were prepared by the hydration method and were evaluated for morphology, size, release study, and encapsulation efficiency. The cytotoxicity of tioxolone and its niosomal form was measured by MTT assay, leishmanicidal activity against promastigote and amastigote by MTT assay, apoptosis by flow cytometry, IL-12, IL-10 and metacaspase gene expression levels by q-PCR. Results: Span/Tween 40 and Span/Tween 60 niosomes had good physical stability as depicted in their size distribution curves and high encapsulation efficiency (>99%). The release profile of the entrapped compounds showed Fickian's model of tioxolone delivery based on diffusion through lipid bilayers. With the IC
ABSTRACT
In this study, we carried out extensive in vitro studies on various concentrations of tioxolone along with benzoxonium chloride and their niosomal forms against Leishmania tropica. Niosomes were prepared by the hydration method and were evaluated for morphology, size, release study, and encapsulation efficiency. This study measured leishmanicidal activity against promastigote and amastigote, apoptosis and gene expression levels of free solution and niosomal-encapsulated tioxolone along with benzoxonium chloride. Span/Tween 60 niosome had good physical stability and high encapsulation efficiency (more than 97%). The release profile of the entrapped compound showed that a gradual release rate. The combination of niosomal forms on promastigote and amastigote were more effective than glucantime. Also, the niosomal form of this compound was significantly less toxic than glucantime (P≤0.05). The flowcytometric analysis on niosomal form of drugs showed that higher number of early apoptotic event as the principal mode of action (89.13% in 200 μg/ml). Also, the niosomal compound increased the expression level of IL-12 and metacaspase genes and decreased the expression level of the IL-10 gene, which further confirming the immunomodulatory role as the mechanism of action. We observed the synergistic effects of these 2 drugs that induced the apoptotic pathways and also up regulation of an immunomodulatory role against as the main mode of action. Also, niosomal form of this combination was safe and demonstrated strong anti-leishmaniasis effects highlights further therapeutic approaches against anthroponotic cutaneous leishmaniasis in future planning.