Buparvaquone Nanostructured Lipid Carrier: Development of an Affordable Delivery System for the Treatment of Leishmaniases

Anti-leishmanial therapies: overcoming current challenges with emerging therapies

INTRODUCTION

Leishmaniasis, including visceral, cutaneous, and mucocutaneous forms, present a major health challenge in tropical regions. Current antileishmanial medications has significant limitations, creating a critical need for novel therapies that are safe and cost-effective with a shorter duration of treatment.

AREAS COVERED

This review explores the critical aspects of existing antileishmanial therapy and targets for future therapeutic developments. It emphasizes the need for new treatment options due to drug resistance, low success rates, toxicity, and high prices associated with current medications. The different forms of leishmaniasis, their clinical manifestations, the challenges associated with their treatment and emerging treatment options are explored in detail.

EXPERT OPINION

The first anti-leishmanial drug pentavalent antimony (SbV) was invented more than 100 years back. Since then, this compound has been used for all forms of leishmaniasis worldwide. For more than 70-80 years after discovery of SbV, no new antileishmanial drugs were developed, reflecting the lack of interest from academia or pharma industry. All three new treatments (Amphotericin-B, paromomycin and miltefosine) which underwent the clinical trials were repurposed drugs. The current pipeline for antileishmanial drugs is empty, with LXE 408 being the only potential drug reaching phase II clinical trial.

Hydroxymethylnitrofurazone lymphatic uptake with nanostructured lipid carrier after oral administration in rats

Background: Leishmaniasis, caused by the protozoan Leishmania sp., infects phagocyte cells present in lymphatic organs. This study demonstrates the influence of nanostructured lipid carrier-loaded hydroxymethylnitrofurazone (NLC-NFOH) on lymphatic uptake using a chylomicron-blocking flow model in rats. Method: Lymphatic uptake of NFOH was assessed 1 h after oral administration of dimethyl sulfoxide with NFOH or NLC-NFOH with and without cycloheximide pretreatment. Result: Dimethyl sulfoxide with NFOH and NLC-NFOH showed NFOH serum concentrations of 0.0316 and 0.0291 μg/ml, respectively. After chylomicron blocking, NFOH was not detected. Conclusion: Despite log P below 5, NFOH was successfully taken up by the lymphatic system. Long-chain fatty acids and particle size might be main factors in these findings. NLC-NFOH is a promising and convenient platform for treating leishmaniasis via oral administration.

The novel treatments based on tissue engineering, cell therapy and nanotechnology for cutaneous leishmaniasis

Cutaneous leishmaniasis (CL) is a global public health issue. Conventional treatments have substantial costs, side effects, and parasite resistance. Due to easy application and inexpensive cost, topical treatment is the optimal approach for CL. It could be used alone or with systemic treatments. Electrospun fibers as drug release systems in treating skin lesions have various advantages such as adjustable drug release rate, maintaining appropriate humidity and temperature, gas exchange, plasticity at the lesion site, similarity with the skin extracellular matrix (ECM) and drug delivery with high efficiency. Hydrogels are valuable scaffolds in the treatment of skin lesions. The important features of hydrogels include preserving unstable drugs from degradation, absorption of wound secretions, high biocompatibility, improving the re-epithelialization of the wound and preventing the formation of scars. One of the issues in local drug delivery systems for the skin is the low permeability of drugs in the skin. Polymeric scaffolds that are designed as microneedle patches can penetrate the skin and overcome this challenge. Also, drug delivery using nanocarriers increases the effectiveness of drugs in lower and more tolerable doses and reduces the toxicity of drugs. The application of cell therapy in the treatment of parasitic and infectious diseases has been widely investigated. The complexity of leishmaniasis treatment requires identifying new treatment options like cell therapy to overcome the disease. Topics investigated in this study include drug delivery systems based on tissue engineering scaffolds, nanotechnology and cell therapy-based studies to reduce the complications of CL.

Development of a Novel Lipid-Based Nanosystem Functionalized with WGA for Enhanced Intracellular Drug Delivery

Despite a considerable number of new antibiotics under going clinical trials, treatment of intracellular pathogens still represents a major pharmaceutical challenge. The use of lipid nanocarriers provides several advantages such as protection from compound degradation, increased bioavailability, and controlled and targeted drug release. Wheat germ agglutinin (WGA) is known to have its receptors on the alveolar epithelium and increase phagocytosis. The present study aimed to produce nanostructured lipid carriers with novel glycosylated amphiphilic employed to attach WGA on the surface of the nanocarriers to improve intracellular drug delivery. High-pressure homogenization was employed to prepare the lipid nanocarriers. In vitro, high-content analysis and flow cytometry assay was employed to study the increased uptake by macrophages when the nanocarriers were grafted with WGA. A lipid nanocarrier with surface-functionalized WGA protein (~200 nm, PDI > 0.3) was successfully produced and characterized. The system was loaded with a lipophilic model compound (quercetin; QU), demonstrating the ability to encapsulate a high amount of compound and release it in a controlled manner. The nanocarrier surface functionalization with the WGA protein increased the phagocytosis by macrophages. The system proposed here has characteristics to be further explored to treat intracellular pathogens.

Oral administration of buparvaquone nanostructured lipid carrier enables in vivo activity against Leishmania infantum

Leishmaniasis, a neglected tropical disease, is prevalent in 98 countries with the occurrence of 1.3 million new cases annually. The conventional therapy for visceral leishmaniasis requires hospitalization due to the severe adverse effects of the drugs, which are administered parenterally. Buparvaquone (BPQ) showed in vitro activity against leishmania parasites; nevertheless, it has failed in vivo tests due to its low aqueous solubility. Though, lipid nanoparticles can overcome this holdback. In this study we tested the hypothesis whether BPQ-NLC shows in vivo activity against L. infantum. Two optimized formulations were prepared (V1: 173.9 ± 1.6 nm, 0.5 mg of BPQ/mL; V2: 232.4 ± 1.6 nm, 1.3 mg of BPQ/mL), both showed increased solubility up to 73.00-fold, and dissolution up to 83.29%, while for the free drug it was only 2.89%. Cytotoxicity test showed their biocompatibility (CC50 >554.4 µM). Besides, the V1 dose of 0.3 mg/kg/day for 10 days reduced the parasite burden in 83.4% ±18.2% (p <0.05) in the liver. BPQ-NLC showed similar leishmanicidal activity compared to miltefosine. Therefore, BPQ-NLC is a promising addition to the limited therapeutic arsenal suitable for leishmaniasis oral administration treatment.

Preclinical Assessment of Ursolic Acid Loaded into Nanostructured Lipid Carriers in Experimental Visceral Leishmaniasis

Ursolic acid, a triterpene produced by plants, displayed leishmanicidal activity in vitro and in vivo; however, the low solubility of this triterpene limits its efficacy. To increase the activity of ursolic acid (UA), this triterpene was entrapped in nanostructured lipid carriers (UA-NLC), physical-chemical parameters were estimated, the toxicity was assayed in healthy golden hamsters, and the efficacy of UA-NLC was studied in experimental visceral leishmanisis. UA-NLC exhibited a spherical shape with a smooth surface with a size of 266 nm. UA-NLC displayed low polydispersity (PDI = 0.18) and good colloidal stability (-29.26 mV). Hamsters treated with UA-NLC did not present morphological changes in visceral organs, and the levels of AST, ALT, urea and creatinine were normal. Animals infected with Leishmania (Leishmania) infantum and treated with UA-NLC showed lower parasitism than the infected controls, animals treated with UA or Amphotericin B (AmB). The therapeutic activity of UA-NLC was associated with the increase in a protective immune response, and it was associated with a high degree of spleen and liver preservation, and the normalization of hepatic and renal functions. These data indicate that the use of lipid nanoparticles as UA carriers can be an interesting strategy for the treatment of leishmaniasis.

Therapeutic advances in the topical treatment of cutaneous leishmaniasis: A review

Cutaneous leishmaniasis has been endemic since decades. Millions of cases are reported worldwide specially in developing and underdeveloped countries. There are 2 major types of cutaneous leishmaniasis based on the causating species found in different regions of the world. These include New and Old World cutaneous leishmaniasis, which are self-healing, but if not treated, these may cause severe scars and many other complications like mucosal involvement. The conventional gold standard treatment for both types is mainly intralesional or parenteral administration of antimonial. Lately, a great deal of research has been done on development of topical treatment based on single agent or combination therapy. This review summarizes the current state of literature regarding therapeutic outcome of topical treatment against cutaneous leishmaniasis caused by different species in different regions.

Preparation and Characterization of Nanostructured Lipid Carriers for Improved Topical Drug Delivery: Evaluation in Cutaneous Leishmaniasis and Vaginal Candidiasis Animal Models

The present study aimed to develop, characterize and evaluate the amphotericin B-loaded nanostructured lipid carriers (AmB-NLCs) for topical treatment of cutaneous leishmaniasis (CL) and vulvovaginal candidiasis (VVC). AmB-NLCs were characterized for particle size, zeta potential, encapsulation efficiency and surface morphology. Prepared NLCs were also characterized for in vitro drug release, ex vivo skin permeation and deposition before evaluating their in vitro and in vivo efficacy. Cytotoxicity of NLCs was assessed on MRC-5 cells, whereas skin irritation potential was evaluated in vivo using rats. Significant accumulation of drug in to the skin supported the topical application potential of drug-loaded NLCs. Encapsulation of AmB in NLCs resulted in enhanced in vitro potency against promastigotes and intracellular amastigotes of L. major JISH 118 (IC50 ± SEM = 0.02 ± 0.1 μM for both) compared with free drug (IC50 ± SEM = 0.15 ± 0.2 & 0.14 ± 0.0, respectively). Similar improved potency of AmB-NLCs was also observed for other Leishmania and fungal strains compared with drug solution. Topical application of AmB-NLCs on L. major-infected BALB/c mice caused a significant reduction in parasite burden per mg of lesion (65 × 108 ± 13) compared with the control group (> 167.8 × 108 ± 11). Topical AmB-NLCs gel demonstrated superior efficacy in the vaginal C. albicans rat model for VVC as compared with plain AmB gel. Moreover, results of in vitro cytotoxicity assay and in vivo skin irritation test confirmed AmB-NLCs to be non-toxic and safe for topical use. In conclusion, NLCs may have promising potential as carrier for topical treatment of various conditions of skin and mucosa.

A new medium-throughput screening design approach for the development of hydroxymethylnitrofurazone (NFOH) nanostructured lipid carrier for treating leishmaniasis

Hydroxymethilnitrofurazone (NFOH) is a nitrofurazone derivative and has potential use in treating leishmaniasis. However, due to low water solubility and bioavailability, NFOH has failed in in vivo tests. Nanostructured lipid carrier (NLC) is an alternative to overcome these limitations by improving pharmacokinetics and modifying drug delivery. This work is focused on developing a novel NFOH-loaded NLC (NLC-NFOH) using a D-optimal mixture statistical design and high-pressure homogenization, for oral administration to treat leishmaniasis. The optimized NLC-NFOH consisted of Mygliol® 840, Gelucire® 50/13, and Precirol® ATO 5 as lipids. These lipids were selected using a rapid methodology Technobis Crystal 16 T M, microscopy, and DSC. Different tools for selecting lipids provided relevant scientific knowledge for the development of the NLC. NLC-NFOH presented a z-average of 198.6 ± 5.4 nm, PDI of 0.11 ± 0.01, and zeta potential of -13.7 ± 0.7 mV. A preliminary in vivo assay was performed by oral administration of NLC-NFOH (2.8 mg/kg) in one healthy male Wistar rat (341 g) by gavage. Blood from the carotid vein was collected, and the sample was analyzed by HPLC. The plasma concentration of NFOH after 5 h of oral administration was 0.22 μg/mL. This same concentration was previously found using free NFOH in the DMSO solution (200 mg/kg), which is an almost 100-fold higher dose. This study allowed a design space development approach of the first NLC-NFOH with the potential to treat leishmaniasis orally.

Formulation, optimization, and in vitro evaluation of nanostructured lipid carriers for topical delivery of Apremilast

This work was aimed to formulate topical Apremilast (APM)-loaded nanostructured lipid carriers (NLCs) for the management of psoriasis. NLCs were prepared by a cold homogenization technique using Compritol 888ATO, oleic acid, Tween 80 and Span 20, and Transcutol P as a solid lipid, liquid lipid, surfactant mixture, and penetration enhancer, respectively. Carbopol 940 was used to convert NLC dispersion into NLC-based hydrogel to improve its viscosity for topical administration. The optimized formulation was characterized for size, polydispersity index (PDI), zeta potential (ZP), percentage of entrapment efficiency (%EE), and surface morphology. Furthermore, viscosity, spreadability, stability, in vitro drug diffusion, ex vivo skin permeation, and skin deposition studies were carried out. APM-loaded NLCs showed a narrow PDI (0.339) with a particle size of 758 nm, a %EE of 85.5%, and a ZP of -33.3 mV. Scanning electron microscopy confirmed spherical shape of NLCs. in vitro drug diffusion and ex vivo skin permeation results showed low drug diffusion, sustained drug release, and 60.1% skin deposition. The present study confirms the potential of the nanostructured lipid form of poorly water-soluble drugs for topical application and increased drug deposition in the skin.

Advances and challenges in nanocarriers and nanomedicines for veterinary application

To ensure success in the development and manufacturing of nanomedicines requires forces of an interdisciplinary team that combines medicine, engineering, chemistry, biology, material and pharmaceutical areas. Numerous researches in nanotechnology applied to human health are available in the literature. Althought, the lack of nanotechnology-based pharmaceuticals products for use exclusively in veterinary pharmacotherapy creates a potential area for the development of innovative products, as these animal health studies are still scarce when compared to studies in human pharmacotherapy. Nano-dosage forms can ensure safer and more effective pharmacotherapy for animals and can more be safer for the consumers of livestock products, once they can offer higher selectivity and smaller toxicity associated with lower doses of the drugs. In addition, the development and production of nanomedicines may consolidate the presence of pharmaceutical laboratories in the global market and can generate greater profit in a competitive business environment. To contribute to this scenario, this article provides a review of the main nanocarriers used in nanomedicines for veterinary use, with emphasis on liposomes, nanoemulsions, micelles, lipid nanoparticles, polymeric nanoparticles, mesoporous silica nanoparticles, metallic nanoparticles and dendrimers, and the state of the art of application of these nanocarriers in drug delivery systems to animal use. Finnaly, the major challenges involved in research, scale-up studies, large-scale manufacture, analytical methods for quality assessment, and regulatory aspects of nanomedicines were discussed.

Applications of Nanomaterials in Leishmaniasis: A Focus on Recent Advances and Challenges

Leishmaniasis is a widely distributed protozoan vector-born disease affecting almost 350 million people. Initially, chemotherapeutic drugs were employed for leishmania treatment but they had toxic side effects. Various nanotechnology-based techniques and products have emerged as anti-leishmanial drugs, including liposomes, lipid nano-capsules, metal and metallic oxide nanoparticles, polymeric nanoparticles, nanotubes and nanovaccines, due to their unique properties, such as bioavailability, lowered toxicity, targeted drug delivery, and biodegradability. Many new studies have emerged with nanoparticles serving as promising therapeutic agent for anti-leishmanial disease treatment. Liposomal Amphotericin B (AmB) is one of the successful nano-based drugs with high efficacy and negligible toxicity. A new nanovaccine concept has been studied as a carrier for targeted delivery. This review discusses different nanotechnology-based techniques, materials, and their efficacies in leishmaniasis treatment and their futuristic improvements.

Co-delivery of buparvaquone and polymyxin B in a nanostructured lipid carrier for leishmaniasis treatment

OBJECTIVES

This study aimed to describe the preparation and in vitro evaluation of a surface-modified nanostructured lipid carrier (NLC) using chitosan and dextran for co-delivery of buparvaquone (BPQ) and polymyxin B (PB) against leishmaniasis.

METHODS

The NLC was prepared using high-pressure homogenisation. Polymyxin B binding and surface modification with biopolymers were achieved by electrostatic interaction. In vitro cytotoxicity was assessed in mouse peritoneal macrophages, and leishmanicidal activity in amastigotes of Leishmania infantum.

RESULTS

The performance attributes of BPQ-NLC, BPQ-NLC-PB[A^-] (anionic) and BPQ-NLC-PB[C⁺] (cationic) were respectively: Z-average 173.9 ± 1.6, 183.8 ± 4.5 and 208.8 ± 2.6 nm; zeta potential -19.6 ± 1.5, -20.1 ± 1.1 and 31.1 ± 0.8 mV; CC₅₀ 583.4 ± 0.10, 203.1 ± 0.04 and 5.7 ± 0.06 μM; IC₅₀ 229.0 ± 0.04, 145.7 ± 0.04 and 150.5 ± 0.02 nM. The NLC in vitro leishmanicidal activity showed up to 3.1-fold increase when compared with free BPQ (P <  0.05, α = 0.05).

CONCLUSIONS

The developed NLC proved to be a promising formulation with which to overcome the drawbacks of current leishmaniasis treatment by the co-delivery of two alternative drugs and a macrophage targeting modified surface.

Development of MART for the Rapid Production of Nanostructured Lipid Carriers Loaded with All-Trans Retinoic Acid for Dermal Delivery

All-trans retinoic acid (ATRA) has been regarded as a wonder drug for many dermatological complications; however, its application is limited due to the extreme irritation, and toxicity seen once it has sufficiently concentrated into the bloodstream from the skin. Thus, the present study was aimed to increase the entrapment of ATRA and minimize its transdermal permeation. ATRA incorporated within nanostructured lipid carriers (NLCs) were produced by a green and facile thin lipid-film based microwave-assisted rapid technique (MART). The optimization was carried out using the response surface methodology (RSM)-driven artificial neural network (ANN) coupled with genetic algorithm (GA). The liquid lipid and surfactants were seen to play a very crucial role culminating in the particle size (< 70 nm), zeta potential (< - 32 mV), and entrapment of ATRA (> 98%). ANN-GA-optimized NLCs required a minimal quantity of the surfactants, formed within 2 min and were stable for 1 year at different storage conditions. The optimized NLC-loaded creams showed a skin retention (ex vivo) to an extent of 87.42% with no detectable drug in the receptor fluid (24 h) in comparison to the marketed cream which released 47.32% (12 h) of ATRA. The results were in good correlation with the in vivo skin deposition studies. The NLCs were biocompatible and non-skin irritant based on the primary irritation index. In conclusion, the NLCs were seen to have a very high potential in overcoming the drawbacks of ATRA for dermal delivery and could be produced conveniently by the MART.

Evaluation of Different Formulations and Routes for the Delivery of the Ionizing Radiation Mitigator GS-Nitroxide (JP4-039)

BACKGROUND/AIM

The mitochondrial targeted GS-nitroxide, JP4-039, is an effective total body irradiation (TBI) mitigator when delivered intravenously (IV) up to 72 h after exposure. Effective systemic and localized administration to oral cavity/oropharynx and esophagus has been demonstrated. The objective of the study was to establish alternatives to IV administration suitable for JP4-039 delivery to mass casualties.

MATERIALS AND METHODS

JP4-039 was administered to C57BL/6 mice by topically applied carboxy-methyl-cellulose microneedle arrays (MNAs) or by intramuscular (IM) injection. Three different formulations that have passed Food and Drug Administration review, namely Captisol, 2-hydroxypropyl-β-cyclodextrin (cyclodextrin), and Miglyol-812-N, were used for drug delivery. Intraoral (IO) administration with each formulation was also evaluated.

RESULTS

All tested formulations and MNAs successfully delivered JP4-039. However, IM delivery of the Miglyol-812-N displayed very efficient and highly reproducible radiation mitigation.

CONCLUSION

Effective IM delivery of JP4-039 in animal models after TBI or partial-body irradiation suggested the use of the Miglyol-812-N formulation in both medical indications and radiation countermeasures.

Promising nanotherapy in treating leishmaniasis

Leishmaniases are infectious diseases caused by an intracellular protozoan in humans by 20 different species of Leishmania among more than 53 species. There are at least twelve million cases of infections worldwide and three hundred and fifty million people are at risk in at least 98 developing countries in Africa, South-East Asia, and the Americas. Only Brazil presented high burden for both visceral leishmaniasis (VL) and cutaneous (CL). Chemotherapy is the main means of dealing with this infection. Nevertheless, only a few effective drugs are available, and each has a particular disadvantage; toxicity and long-term regimens compromise most chemotherapeutic options, which decreases patient compliance and adherence to the treatment and consequently the emergence of drug-resistant strains. Nano drug delivery systems (NanoDDS) can direct antileishmanial drug substances for intracellular localization in macrophage-rich organs such as bone marrow, liver, and spleen. This strategy can improve the therapeutic efficacy and reduce the toxic effects of several antileishmanial drug substances. This review is an effort to comprehensively compile recent findings, with the aim of advancing understanding of the importance of nanotechnology for treating leishmaniases.