Covalent Functionalized Self-Assembled Lipo-Polymerosome Bearing Amphotericin B for Better Management of Leishmaniasis and Its Toxicity Evaluation

Abstract

Amphotericin B remains the preferred choice for leishmanial infection, but it has limited clinical applications due to substantial dose limiting toxicities. In the present work, AmB has been formulated in lipo-polymerosome (L-Psome) by spontaneous self-assembly of synthesized glycol chitosan-stearic acid copolymer. The optimized L-Psome formulation with vesicle size of 243.5 ± 17.9 nm, PDI of 0.168 ± 0.08 and zeta potential of (+) 27.15 ± 0.46 mV with 25.59 ± 0.87% AmB loading was obtained. The field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopy (HRTEM) images suggest nearly spherical morphology of L-Psome. An in vitro study showed comparatively sustained AmB release (66.082 ± 1.73% within 24 h) and high plasma stability compared to commercial Ambisome and Fungizone, where glycol chitosan content was found to be efficient in preventing L-Psome destabilization in the presence of plasma protein. In vitro and in vivo toxicity studies revealed less toxicity of AmB-L-Psome compared to commercialized Fungizone and Ambisome favored by monomeric form of AmB within L-Psome, observed by UV-visible spectroscopy. Experimental results of in vitro (macrophage amastigote system) and in vivo (Leishmania donovani infected hamsters) illustrated the efficacy of AmB-L-Psome to augment effective antileishmanial properties supported by upregulation of Th-1 cytokines (TNF-α, IL-12 and IFN-γ) and inducible nitric oxide synthase, and downregulation of Th-2 cytokines (TGF-β, IL-10 and IL-4), measured by quantitative mRNA analysis by real time PCR (RT-PCR). Conclusively, developed L-Psome system could be a viable alternative to the current less stable, toxic commercial formulations and developed as a highly efficacious drug delivery system.

New delivery systems for amphotericin B applied to the improvement of leishmaniasis treatment

“…In addition, Kumar et al (47) developed carboxy-terminated poly(D,L-lactide-co-glycolide)-block-poly(ethylene glycol) (PLGA-PEG)-encapsulated AmpB nanoparticles to increase the solubility of AmpB and to target the macrophages of infected tissues during L. donovani infection. Their study showed that the cytotoxicity of extracellular promastigotes when using PLGA-PEG-encapsulated AmpB was signifi cantly lower than that with free AmpB and that the inhibition of amastigote infection in the spleens of the animals was signifi cantly higher than with free AmpB.…”

Synergistic enhancement of parasiticidal activity of amphotericin B using copaiba oil in nanoemulsified carrier for oral delivery: an approach for non‐toxic chemotherapy

“…Figure 7A illustrates the haemolytic effect of AmB, which was high even at the minimum concentration used in the experiment; this was expected because AmB lyses RBCs by an active process involving pore formation. The CopNEC-AmB showed a smaller haemolytic effect possibly due to encapsulation of AmB inside the emulsified core of the formulation and, moreover, the presence of a low concentration of dimeric and multimeric aggregated forms of AmB reduced the degree of haemolysis (Gupta et al, 2014b). The CopNEC caused less haemolysis than plain Cop because Cop forms the core of the CopNEC formulation.…”

“…The haemolytic activity of the different formulations (CopNEC-AmB and AmB) containing AmB equivalent to 5, 10 and 20 μg·mL −1 and CopNEC and Cop were determined on erythrocytes (Gupta et al, 2014b). The erythrocytes (RBCs) were collected from the blood of Wistar rats by centrifugation for 10 min at 2000× g, washing thrice with isotonic PBS (pH 7.4) and were dispersed in PBS to obtain 3% (w v −1 ) haematocrit.…”

“…Cytotoxicity was determined by the MTT proliferation assay for different formulations of CopNEC-AmB, CopNEC, Cop and AmB at 5, 10 and 20 μg·mL −1 equivalent AmB concentrations (Gupta et al, 2014b). For measurement of cytotoxicity, J774A macrophages (5 × 10 4 cells per well) in RPMI-1640 medium were placed in to 96-well plates and allowed to adhere overnight.…”

Nanostructured delivery systems with improved leishmanicidal activity: a critical review

“…122 Chitosan was also chemically modified into glycol chitosan stearate, an amphiphilic copolymer that forms carriers with a hydrophilic shell and a hydrophobic core comprising stearic acid. 123 By increasing the rigidity of the bilayer of so-called lipo-polymerosomes (L-Psomes) using cholesterol, a very large amount of AmpB was loaded (25%), exploiting the hydrophobic interaction with the stearic acid chain. The AmpB-L-Psomes proved to be a biologically safe and stable delivery system, with improved efficacy compared to commercial formulations; they can thus be proposed as an alternative low-cost product.…”