In vivo evaluation of the efficacy of albendazole sulfoxide and albendazole sulfoxide loaded solid lipid nanoparticles against hydatid cyst

Cationized albumin conjugated solid lipid nanoparticles as vectors for delivery of albendazole against cystic echinococcosis

BACKGROUND

Cystic echinococcosis (CE) is a common neglected parasitic disease. Nanoparticles containing drugs have been widely utilized in various formulations for several purposes, including improving the bioavailability of drugs by increasing the solubility and dissolution rate of the nanoparticles. The purpose of this study was to evaluate the effects of solid lipid nanoparticles containing albendazole and conjugated to albumin (B-SLN + ABZ) as a novel treatment approach for hydatid cysts in vivo.

METHODS

Albendazole-loaded solid lipid nanoparticles were prepared by emulsification and solvent evaporation method. The experimental mice were assessed for prophylactic and therapeutic effects of the drugs. Ultrastructural changes were observed by transmission electron microscopy.

RESULTS

The variance analysis of the fitted model indicated that the Glyceryl monostearate (GMS)/soy lecithin concentration ratio and the amount of albendazole had a significant effect on nanoparticle size. The GMS/soy lecithin concentration ratio and the amount of albendazole had a notable effect on nanoparticle polydispersity index (PdI) and entrapment efficiency (EE%), respectively. During chemoprophylaxis, the B-SLN + ABZ group showed a lower number and weight of cysts (0.90 ± 0.73 and 15.01 ± 10.46, respectively) compared with the ABZ + SLN group (1.4 ± 0.51 and 26.73 ± 9.92, respectively). In addition, therapeutic efficacy analysis showed a significant reduction in wet weights of metacestodes in mice treated with both B-SLN + ABZ (29.37 ± 13.82 mg) and SLN + ABZ (35.88 ± 7.49 mg) compared with the control group (59.78 ± 3.80 mg).

CONCLUSIONS

The results showed that B-SLN + ABZ nanoparticles were more effective against E. granulosus cysts compared with free ABZ. The cysts in the animals receiving B-SLN + ABZ every 24 h showed more ultrastructural changes.

Assessment of the Effects of Albendazole-Loaded Sulfonated Graphene Oxide on Echinococcus granulosus Protoscoleces: An In Vitro Investigation

Objectives

Due to Albendazole's relatively low efficacy and bioavailability, Echinococcosis has proven a challenge to manage successfully, with several studies investigating ways to improve the outcome, mainly showing mixed results. We, therefore, aimed to evaluate whether Sulfonated Graphene Oxide (S-GO), as nanocarriers, could improve the mentioned outcome.

Methods

Echinococcus protoscoleces were divided into four groups based on the agent they received, which comprised control, S-GO, Albendazole, and Albendazole-loaded S-GO (S-GO-Albendazole). Then, the Bax and Bcl-2 gene expression levels and the number of surviving protoscoleces in each group were determined.

Results

Bax gene expression increased by 121% in the 50 μg/ml concentration of the S-GO-Albendazole, while Bcl-2 gene expression decreased by 64%. Moreover, S-GO-Albendazole was approximately 18% more effective at neutralizing protoscoleces than Albendazole and 14% and 31% more effective at improving the expression of the mentioned genes, respectively (p < 0.05). In addition, the number of surviving protoscoleces after exposure to the mentioned concentration reduced by approximately 99%.

Conclusions

S-GO, despite not having significant lethality on protoscoleces, significantly increased the lethality of Albendazole and, therefore, is a suitable nanocarrier. However, we recommend conducting in vivo and clinical studies to more accurately determine this nanocomplex's potential and side effects.

Primary extrahepatic hydatid cyst of the thigh, an unusual presentation of sciatica: A case report of a diagnostic challenge

INTRODUCTION

Sciatica, a condition characterized by pain along the sciatic nerve distribution, is commonly associated with nerve compression or irritation. However, its etiology can vary, including rare non-spinal causes such as hydatid cysts. We present a case of hydatid cyst in the thigh causing sciatica-like symptoms, highlighting the diagnostic challenges and management approach.

CASE PRESENTATION

A 40-year-old patient with a history of pulmonary tuberculosis presented with persistent lumbosciatic pain despite conservative treatment. Physical examination revealed left sciatica without spinal abnormalities. MRI revealed a hydatid cyst in the thigh, causing nerve irritation. Surgical resection of the cyst was performed, achieving symptom resolution.

DISCUSSION

Hydatid cysts in skeletal muscles are rare, with atypical presentations complicating diagnosis. Localization in the thigh, particularly the biceps femoris muscle, is uncommon. Diagnostic modalities include imaging and serological tests, while treatment involves surgical excision and postoperative albendazole therapy.

CONCLUSION

Recognition of rare presentations like thigh hydatid cysts causing sciatica-like symptoms is crucial for timely diagnosis and management. This case emphasizes the importance of considering unusual etiologies in refractory sciatica cases and underscores the complexity of medical diagnosis. Increased awareness among healthcare providers can lead to improved patient outcomes and prevent diagnostic delays.

Development of solid lipid nanoparticles-loaded drugs in parasitic diseases

Parasites cause illnesses with broad spectrum of symptoms from mild to severe, and are responsible for a significant number of outbreaks in the world. Current anti-parasitic drugs are toxic and have significant side effects. Nano-carriers are believed to obviate the limitations of conventional drugs via decreasing side effects and increasing target delivery and drug permeability with a controlled prolonged release of a drug. Solid lipid nanoparticles (SLNs) are lipid nanoparticles (LNPs), which have frequently been practiced. Suitable release rate, stability, and target delivery make SLNs a good alternative for colloidal carriers. SLNs are supposed to have great potential to deliver natural products with anti-parasitic properties. Nanoparticles have employed to improve stability and capacity loading of SLNs, during recent years. This review describes development of SLNs, the methods of preparation, characterization, and loaded drugs into SLNs in parasitic diseases. In addition, we summarize recent development in anti-parasitic SLNs-loaded drugs.

The efficiency of fabricated Ag/ZnO nanocomposite using Ruta chalepensis L. leaf extract as a potent protoscolicidal and anti-hydatid cysts agent

BACKGROUND

As a consequence of their eco-friendliness, simplicity and non-toxicity, the fabrication of metal and metal oxide nanoparticles using greener chemistry has been a highly attractive research area over the last decade.

AIM

In this study focused on the fabrication of silver-Zinc oxide nanocomposite (Ag-ZnO NCs) using Ruta chalepensis leaf extract and evaluating its potential biological activities, against Echinococcus granulosus in an in vitro and in vivo model using BALB/c mice.

METHODS

In this study, the synthesis of Ag-ZnO NCs was accomplished using local R. chalepensis leaf extracts. The synthesized nanocomposites were identified using UV-Vis, SEM-EDX, XRD, and FTIR. For a short-term assessment of acute toxicity, BALB/c mice were given the prepared NCs orally. Dual sets of mice were also intraperitoneally injected with protoscoleces for secondary echinococcosis infection. Furthermore, a blood compatibility test was carried out on the nanocomposites.

RESULTS

The synthesized Ag-ZnO NCs presented a surface plasmon peak at 329 and 422 nm. The XRD, SEM, and EDX confirmed the purity of the Ag-ZnO NCs. The FTIR spectra indicated the formation of Ag-ZnO NCs. Compared to the untreated infected mice, the treated-infected animals displayed an alteration in the appearance of the hepatic hydatid cysts from hyaline to whitish cloudy with a rough surface appearance. Lysis of RBCs at various doses of Ag-ZnONCs was significantly less than the positive contro,.

CONCLUSION

These findings revealed that the Ag-ZnO NCs didn't cause any adverse symptoms and no mortality was observed in all administered groups of mice. The obtained outcomes confirmed that concentrations of up to 40 μg/mL of the bio-fabricated Ag-ZnONCs induced no notable harm to the red blood cells.

Hydatid Disease of the Liver

Background

Echinococcosis also known as hydatid disease is a zoonotic parasitic disease caused by a tapeworm. It has a worldwide distribution. For long, it was thought to be a problem of the poorly sanitized "third world" and not given the importance it deserved. However, its occurrence in countries like Australia and New Zealand and recently in countries in Central Europe has meant that it is included in a WHO list of neglected diseases, has recently been the subject of extensive epidemiological studies, and has been the recipient of increased research funding.

Summary

The diagnosis is still based on clinical presentation in an endemic area corroborated with typical findings on imaging which routinely include ultrasound and CT scan. Serological tests have been used in some centers to support the diagnosis. Treatment depends on the site of involvement and can vary from wait and watch to extensive radical surgical procedures. The common element of all treatments is the addition of albendazole which forms an essential cornerstone of all treatment protocols. Inspite having been used for a fairly long time, there is still no consensus on the dose, duration, and timing of therapy with albendazole.

Key Message

Hydatid disease continues to be a significant global health problem inspite of a good understanding of its life cycle and rising standards of public sanitation. Though diagnosis is straightforward and not expensive, treatment can sometimes be complicated. The addition of albendazole to all treatment protocols is an important advance, but firm guidelines on duration of its use are still awaited.

Status and prospect of novel treatment options toward alveolar and cystic echinococcosis

Cystic echinococcosis (CE) and alveolar echinococcosis (AE) are the two most important global parasitic infectious diseases caused by species of Echinococcus granulosus and E. multilocularis, respectively. Although numerous trials have been performed in search of novel therapeutic options to curb the neglected zoonosis, no other nonsurgical options are currently available to replace the licensed anti echinococcal drugs albendazole (ABZ) and mebendazole (MBZ). A safer and more effective treatment plan for echinococcosis is therefore urgently needed to compensate for this therapeutic shortfall. Here, we present a review of the literature for state-of-the-art valuable anti-parasitic compounds and novel strategies that have proved effective against CE and AE, which includes details about the pharmaceutical type, practical approach, experimental plan, model application and protoscolecidal effects in vivo and in vitro. The content includes the current application of traditional clinical chemicals, the preparation of new compounds with various drug loadings, repurposing findings, combined programs, the prospects for Chinese herbal medicines, non-drug administrations and the exploration of target inhibitors based on open-source information for parasitic genes. Next the conventional experimental projects and pharmacodynamic evaluation methods are systematically summarized and evaluated. The demands to optimize the construction of the echinococcosis model and improve the dynamic monitoring method in vivo are also discussed given the shortcomings of in vivo models and monitoring methods.

Assessment of the Therapeutic Efficacy of Silver Nanoparticles against Secondary Cystic Echinococcosis in BALB/c Mice

Background: Cystic echinococcosis (CE) is a highly prevalent parasitic disease resulting from the hydatid cyst of Echinococcus granulosus. It is also described as a zoonotic disease and considered a neglected tropical infection. Aim: This study assessed the antiparasitic activity of silver nanoparticles (AgNPs), against E. granulosus infection in BALB/c mice. Methods: The green synthesis of AgNPs was accomplished using Zizyphus spina-christi leaves. AgNPs were orally administered to BALB/c mice for acute short-term toxicity evaluation, in doses of 50 mg, 100 mg, 200 mg, and 300 mg/kg, and observations for toxic signs were carried out at 24, 48 h, and 14 days, continuously. Moreover, a total of 20 mice divided into two groups were intraperitoneally administered with 1500 viable protoscoleces for secondary hydatidosis infection. Results: The results showed that AgNPs did not induce any adverse effects or signs and no death, in either group of mice. The histopathological findings in the liver, kidneys, and intestine of the mice administered with AgNPs revealed mild histological effects compared with the control ones. The treated-infected mice showed a change in the appearance of the liver hydatid cysts from hyaline to milky cloudy compared with the untreated infected mice. Conclusion: Biosynthesized AgNPs showed anti-hydatic effects and are suggested as anti-echinococcal cyst treatment.

In vitro evaluation of albendazole-loaded nanostructured lipid carriers on Echinococcus granulosus microcysts and their prophylactic efficacy on experimental secondary hydatidosis

To enhance the therapeutic effects of albendazole (ABZ) on Echinococcus granulosus protoscoleces and metacestodes, ABZ-loaded nanostructured lipid carriers (ABZ-NLCs) are prepared by the hot high-speed homogenization method. Protoscoleces and microcysts were treated in vitro with free ABZ and ABZ-NLCs (concentrations of 1, 5, and 10 μg/ml), and the corresponding effects were monitored by methylene blue exclusion test and scanning and transmission electron microscopy. Chemoprophylactic treatment was performed on Balb/C mice 1 day before intraperitoneal injection of viable protoscoleces. The drugs were administered daily by intragastric inoculation for a period of 30 days. The prophylactic efficacy was assessed based on the number and weight of cysts developed in treated mice. The ultrastructural alterations in cysts were examined by transmission electron microscopy. After 18 days, all the protoscoleces incubated with 10 μg/ml ABZ-NLCs were killed, while 51.25 ± 4.03% of the protoscoleces incubated with 10 μg/ml free ABZ were still viable. Microcysts treated with ABZ-NLCs underwent degenerative alterations in a shorter time than when free ABZ was applied. The mean weight of the cysts recovered from mice of ABZ-NLCs group was significantly lower than that of the free ABZ group (P < 0.05), yielding prophylactic efficacy of 92.45% and 38.53%, respectively. The cysts treated with ABZ-NLCs showed marked ultrastructural changes in the germinal layer. This study demonstrated that both in vitro and in vivo treatments with ABZ-NLCs are significantly more efficient than treatment with free ABZ against E. granulosus protoscoleces, metacestodes, and prevention of cyst development in mice.

High Potency of Organic and Inorganic Nanoparticles to Treat Cystic Echinococcosis: An Evidence-Based Review

Since there is no potential, effective vaccine available, treatment is the only controlling option against hydatid cyst or cystic echinococcosis (CE). This study was designed to systematically review the in vitro, in vivo, and ex vivo effects of nanoparticles against hydatid cyst. The study was carried out based on the 06- PRISMA guideline and registered in the CAMARADES-NC3Rs Preclinical Systematic Review and Meta-analysis Facility (SyRF) database. The search was performed in five English databases, including Scopus, PubMed, Web of Science, EMBASE, and Google Scholar without time limitation for publications around the world about the protoscolicdal effects of all the organic and inorganic nanoparticles without date limitation in order to identify all the published articles (in vitro, in vivo, and ex vivo). The searched words and terms were: “nanoparticles”, “hydatid cyst”, “protoscoleces”, “cystic echinococcosis”, “metal nanoparticles”, “organic nanoparticles”, “inorganic nanoparticles, “in vitro”, ex vivo”, “in vivo”. Out of 925 papers, 29 papers including 15 in vitro (51.7%), 6 in vivo (20.7%), ex vivo 2 (6.9%), and 6 in vitro/in vivo (20.7%) up to 2020 met the inclusion criteria for discussion in this systematic review. The results demonstrated the most widely used nanoparticles in the studies were metal nanoparticles such as selenium, silver, gold, zinc, copper, iron nanoparticles (n = 8, 28.6%), and metal oxide nanoparticles such as zinc oxide, titanium dioxide, cerium oxide, zirconium dioxide, and silicon dioxide (n = 8, 28.6%), followed by polymeric nanoparticles such as chitosan and chitosan-based nanoparticles (n = 7, 25.0%). The results of this review showed the high efficacy of a wide range of organic and inorganic NPs against CE, indicating that nanoparticles could be considered as an alternative and complementary resource for CE treatment. The results demonstrated that the most widely used nanoparticles for hydatid cyst treatment were metal nanoparticles and metal oxide nanoparticles, followed by polymeric nanoparticles. We found that the most compatible drugs with nanoparticles were albendazole, followed by praziquantel and flubendazole, indicating a deeper understanding about the synergistic effects of nanoparticles and the present anti-parasitic drugs for treating hydatid cysts. The important point about using these nanoparticles is their toxicity; therefore, cytotoxicity as well as acute and chronic toxicities of these nanoparticles should be considered in particular. As a limitation, in the present study, although most of the studies have been performed in vitro, more studies are needed to confirm the effect of these nanoparticles as well as their exact mechanisms in the hydatid cyst treatment, especially in animal models and clinical settings.

Solid Lipid Nanoparticles for Drug Delivery: Pharmacological and Biopharmaceutical Aspects

In the golden age of pharmaceutical nanocarriers, we are witnessing a maturation stage of the original concepts and ideas. There is no doubt that nanoformulations are extremely valuable tools for drug delivery applications; the current challenge is how to optimize them to ensure that they are safe, effective and scalable, so that they can be manufactured at an industrial level and advance to clinical use. In this context, lipid nanoparticles have gained ground, since they are generally regarded as non-toxic, biocompatible and easy-to-produce formulations. Pharmaceutical applications of lipid nanocarriers are a burgeoning field for the transport and delivery of a diversity of therapeutic agents, from biotechnological products to small drug molecules. This review starts with a brief overview of the characteristics of solid lipid nanoparticles and discusses the relevancy of performing systematic preformulation studies. The main applications, as well as the advantages that this type of nanovehicles offers in certain therapeutic scenarios are discussed. Next, pharmacokinetic aspects are described, such as routes of administration, absorption after oral administration, distribution in the organism (including brain penetration) and elimination processes. Safety and toxicity issues are also addressed. Our work presents an original point of view, addressing the biopharmaceutical aspects of these nanovehicles by means of descriptive statistics of the state-of-the-art of solid lipid nanoparticles research. All the presented results, trends, graphs and discussions are based in a systematic (and reproducible) bibliographic search that considered only original papers in the subject, covering a 7 years range (2013-today), a period that accounts for more than 60% of the total number of publications in the topic in the main bibliographic databases and search engines. Focus was placed on the therapeutic fields of application, absorption and distribution processes and current efforts for the translation into the clinical practice of lipid-based nanoparticles. For this, the currently active clinical trials on lipid nanoparticles were reviewed, with a brief discussion on what achievements or milestones are still to be reached, as a way of understanding the reasons for the scarce number of solid lipid nanoparticles undergoing clinical trials.

Evaluation of the efficacy of albendazole sulfoxide (ABZ-SO)-loaded chitosan-PLGA nanoparticles in the treatment of cystic echinococcosis in laboratory mice

Albendazole is known as the drug of choice for medical treatment of cystic echinococcosis (CE). Albendazole sulfoxide (ABZ-SO), as the main active metabolite of albendazole, has low efficacy in the disease due to low water solubility and poor absorptivity. PLGA nanoparticles (NPs) enhance the dissolution of poorly soluble drugs, and chitosan (CS) coating enhances oral drug delivery of NPs. In this study, the efficacy of ABZ-SO-loaded CS-PGLA NPs in the treatment of CE was evaluated in laboratory mice. ABZ-SO-loaded CS-PGLA NPs were prepared by nanoprecipitation and characterized by dynamic light scattering method and scanning electron microscopy. Thirty mice were intraperitoneally infected by 1000 protoscoleces of Echinococcus granulosus. Ten months later, the mice were allocated into 3 groups: groups 1 and 2 were treated with ABZ-SO and ABZ-SO-loaded CS-PGLA NPs, respectively, and the mice in group 3 remained untreated as the control group. The drugs were administered by gavage for 45 days at a daily dose of 10 mg/kg. Finally, all mice were opened and the cysts were collected, counted, weighed, and measured separately. The therapeutic effect of ABZ-SO in the number, weight, and volume of the cysts were not statistically significant compared with those in ABZ-SO-loaded CS-PGLA NPs and the control group. However, the therapeutic effect of ABZ-SO-loaded CS-PGLA NPs in the weight and volume of cysts were statistically significant when compared with that in the control group (p ˂ 0.05). In conclusions, this study revealed that ABZ-SO-loaded CS-PGLA NPs could enhance the therapeutic efficacy of ABZ-SO in the treatment of CE in laboratory mice.

Potential of Nanoparticles as Permeation Enhancers and Targeted Delivery Options for Skin: Advantages and Disadvantages

The topical route of administration has many advantages for the treatment of various skin disorders as well as cosmeceutical purposes. This route bypasses hepatic first-pass effect and systemic availability of many pharmaceuticals is limited to skin organelles such as hair follicles and so could avoid unwanted adverse reactions and increase the localized therapeutic effect. Despite such attributed advantages of the topical route, the most important challenge is skin barrier characteristics that should be overcome to obtain dermal or trans-dermal drug delivery. Different approaches have been recruited to overcome this barrier. In this review, different types of nanoparticles for skin permeation enhancement and targeted delivery to skin organelles are discussed. The potential mechanisms of each nanocarrier in permeation enhancement and dermal delivery are considered and finally, the most important advantages and disadvantages of each group are summarized.

Ricobendazole nanocrystals obtained by media milling and spray drying: Pharmacokinetic comparison with the micronized form of the drug

Helminthic infections are produced by different types of worms and affect millions of people worldwide. Benzimidazole compounds such as ricobendazole (RBZ) are widely used to treat helminthiasis. However, their low aqueous solubility leads to poor gastrointestinal dissolution, absorption and potential lack of efficacy. The formulation of nanocrystals (NCs) have become the strategy of preference for hydrophobic drugs. In this work, we prepared RBZ NCs (RBZ-NCs) by an optimized combination of bead milling and spray-drying. Following the physicochemical characterization, a comparative pharmacokinetic evaluation of RBZ-NCs was performed in dogs using as controls a micronized powdered form of RBZ (mRBZ) and a physical mixture of drug and stabilizer 1:1 (PM). The particle size of the redispersed RBZ-NCs was 181.30 ± 5.93 nm, whereas DSC, PXRD and FTIR analyses demonstrated that the active ingredient RBZ remained physicochemically unchanged after the manufacture process. RBZ-NCs exhibited improved in vitro biopharmaceutical behaviour when compared to mRBZ. Consequently, the pharmacokinetic trial demonstrated a significant increase in the drug oral absorption, with an AUC_0-∞ 1.9-fold higher in comparison to that obtained in animals treated with mRBZ. This novel formulation holds substantial potential for the development of new/alternative treatments for helminth infections both in human and veterinary medicine.

Nanoparticles for antiparasitic drug delivery

As an emerging novel drug carrier, nanoparticles provide a promising way for effective treatment of parasitic diseases by overcoming the shortcomings of low bioavailability, poor cellular permeability, nonspecific distribution and rapid elimination of antiparasitic drugs from the body. In recent years, some kinds of ideal nanocarriers have been developed for antiparasitic drug delivery. In this review, the progress of the enhanced antiparasitic effects of different nanoparticles payload and their influencing factors were firstly summarized. Secondly, the transport and disposition process in the body were reviewed. Finally, the challenges and prospects of nanoparticles for antiparasitic drug delivery were proposed. This review will help scholars to understand the development trend of nanoparticles in the treatment of parasitic diseases and explore strategies in the development of more efficient nanocarriers to overcome the difficulty in the treatment of parasite infections in the future.

Evaluation of the therapeutic efficacy of albendazole-loaded silver nanoparticles against Echinococcus granulosus infection in experimental mice

The drug of choice for treatment of hydatid disease, albendazole (ABZ) is a poorly water-soluble drug; thus, enhancing its solubility is required. Among metal nanoparticles (NPs), silver (Ag) NPs showed antimicrobial efficacies. Therefore, this study was conducted to evaluate nanosilver particles (Ag NPs) free or combined with albendazole against Echinococcus granulosus infection in vivo. In this study, besides the normal control group (GI) (n = 5), 80 mice were infected with 2000 viable protoscoleces intraperitoneally then divided equally (n = 20) into the infected control (GII), ABZ-treated (GIII), nanosilver-treated (GIV) and ABZ-loaded-Ag NPs-treated (GV) groups. On the 90th post-infection day, treatment was started and continued for 8 weeks then the experiment was terminated. Each mouse was subjected to measurement of hydatid cysts' sizes and weights, serum IFN-γ, liver enzymes; histopathological and transmission electron microscopy studies. In all treated groups, there were significant reductions of hydatid cysts' sizes and weights; however, the highest efficacy rate (63.9%) was detected in group V associated with obvious ultrastructure alterations of the cysts. The liver tissues of group II showed intense granulomatous reactions, congestion, fibrosis, necrosis and steatosis associated with significant increases in serum IFN-γ and liver enzymes. Interestingly, the best antiparasitic effect and the most significant reduction of IFN-γ towards the normal values were found in GV. Moreover, Ag NPs had reduced the toxic effects of ABZ such as necrosis, steatosis and the elevated serum liver enzymes. Therefore, loading ABZ on Ag NPs could be a potential method to improve ABZ efficacy against hydatid disease.

Therapeutic efficacy of nanocompounds in the treatment of cystic and alveolar echinococcoses: challenges and future prospects

Echinococcus granulosus sensu lato and E. multilocularis are the causative agents of life-threatening cystic and alveolar echinococcoses (CE and AE), respectively, which lead to serious public health concerns across the globe. Benzimidazoles (BMZs) are the drugs of choice for the treatment of human CE and AE. Presently, the chemotherapeutic failures of BMZs against CE and AE are caused by their low aqueous solubility, poor absorption, and consequently their erratic bioavailability. Among the BMZ compounds used for CE/AE treatment, albendazole (ABZ) and mebendazole (MBZ) are the only drugs licensed for human use. Nevertheless, the administration of these BMZs for a long period of time leads to undesirable adverse effects. Therefore, there is an urgent need for designing new formulations of BMZs with increased bioavailability. To bridge these therapeutic gaps, nanoparticle enantiomers of ABZ and drug delivery systems based on nanostructured entities currently provide an interesting new formulation of already existing drugs to improve the pharmacokinetic effects of BMZs. This study provides an overview of the tested nanocompounds against E. granulosus and E. multilocularis, including their effective dose, type of nanoparticles (NPs), assay setting, and therapeutic outcomes. This review suggests that BMZ derivatives loaded in NPs can significantly improve the scolicidal and cysticidal activities compared with single BMZ. Moreover, BMZ-loaded polymeric NPs show a tendency to increase mortality rate against protoscoleces and microcysts compared with metallic formulations, nanoemulsions, lipid nanocapsules, solid lipid NPs, liposomes, and nanocrystals. In the future, the use of the newly structured entities, attained by bridging ligands to the modified surface of NPs, as well as the electromagnetically produced nanodrugs could be helpful for developing fine-tuned formulations as an alternative to the already existing drugs against these neglected parasitic infections.

Albendazole-lipid nanocapsules: Optimization, characterization and chemoprophylactic efficacy in mice infected with Echinococcus granulosus

Cystic echinococcosis (CE), which is caused during the metacestode larval stage of Echinococcus granulosus, is a life-threatening disease and is very difficult to treat. At present, the FDA-approved antihelmintic drugs are mebendazole (MBZ), albendazole (ABZ) and its principal metabolite ABZ sulfoxide (ABZSO), but as these have a therapeutic efficacy over 50%, underlining the need for new drug delivery systems. The aim of this work was the optimization and characterization of previously developed ABZ lipid nanocapsules (ABZ-LNCs) and evaluate their efficacy in mice infected with E. granulosus. LNCs were prepared by the phase inversion technique and characterized in terms of size, surface charge, drug loading, and in vitro stability followed by an in vivo proof-of-concept using a murine model infected with E. granulosus. Stable particle dispersions with a narrow size distribution and high efficiency of encapsulation (≥90%) were obtained. ABZ-LNCs showed a greater chemoprophylactic efficacy than ABZ suspension administered by the oral route as 4 out of the 10 ABZ-LNCs treated mice did not develop any cysts, whereas the infection progressed in all mice from the ABZ suspension group. Regarding the ultrastructural studies of cysts, mice treated with ABZ-LNCs or ABZ suspension revealed changes in the germinal layer. However, the extent of the damage appeared to be greater after ABZ-LNC administration compared to the suspension treatment. These results suggest that ABZ-LNCs could be a promising novel candidate for ABZ delivery to treat CE.

Effect of Acyclovir Solid Lipid Nanoparticles for the Treatment of Herpes Simplex Virus (HSV) Infection in an Animal Model of HSV-1 Infection

BACKGROUND

Acyclovir use is limited by a high frequency of administration of five times a day and low bioavailability. This leads to poor patient compliance.

OBJECTIVES

To overcome the problem of frequent dosing, we used nanotechnology platform to evaluate the proof of concept of substituting multiple daily doses of acyclovir with a single dose.

METHODS

Acyclovir was formulated as solid lipid nanoparticles (SLN). The nanoparticles were characterized for particle size, surface charge and morphology and in vitro drug release. The pharmacokinetic and pharmacodynamic of SLN acyclovir were compared with conventional acyclovir in a mouse model.

RESULTS

SLN showed drug loading of 90.22% with 67.44% encapsulation efficiency. Particle size was found to be of 131 ± 41.41 nm. In vitro drug release showed 100% release in SIF in 7 days. AUC0-∞ (119.43 ± 28.74 μg/ml h), AUMC0-∞ (14469 ± 4261.16 μg/ml h) and MRT (120.10 ± 9.21 h) were significantly higher for ACV SLN as compared to ACV AUC0-∞ (12.22 ± 2.47 μg/ml h), AUMC0-∞ (28.78 ± 30.16 μg/ml h) and MRT (2.07 ± 1.77 h), respectively (p<0.05). In mouse model, a single dose of ACV SLN was found to be equivalent to ACV administered as 400mg TID for 5 days in respect to lesion score and time of healing.

CONCLUSION

The proof of concept of sustained-release acyclovir enabling administration as a single dose was thus demonstrated.

Identification of Functional MKK3/6 and MEK1/2 Homologs from Echinococcus granulosus and Investigation of Protoscolecidal Activity of Mitogen-Activated Protein Kinase Signaling Pathway Inhibitors In Vitro and In Vivo

Cystic echinococcosis is a zoonosis caused by the larval stage of Echinococcus granulosus sensu lato There is an urgent need to develop new drugs for the treatment of this disease. In this study, we identified two new members of mitogen-activated protein kinase (MAPK) cascades, MKK3/6 and MEK1/2 homologs (termed EgMKK1 and EgMKK2, respectively), from E. granulosus sensu stricto Both EgMKK1 and EgMKK2 were expressed at the larval stages. As shown by yeast two-hybrid and coimmunoprecipitation analyses, EgMKK1 interacted with the previously identified Egp38 protein but not with EgERK. EgMKK2, on the other hand, interacted with EgERK. In addition, EgMKK1 and EgMKK2 displayed kinase activity toward the substrate myelin basic protein. When sorafenib tosylate, PD184352, or U0126-ethanol (EtOH) was added to the medium for in vitro culture of E. granulosus protoscoleces (PSCs) or cysts, an inhibitory and cytolytic effect was observed via suppressed phosphorylation of EgMKKs and EgERK. Nonviability of PSCs treated with sorafenib tosylate or U0126-EtOH, and not with PD184352, was confirmed through bioassays, i.e., inoculation of treated and untreated protoscoleces into mice. In vivo treatment of E. granulosus sensu stricto-infected mice with sorafenib tosylate or U0126-EtOH for 4 weeks demonstrated a reduction in parasite weight, but the results did not show a significant difference. In conclusion, the MAPK cascades were identified as new targets for drug development, and E. granulosus was efficiently inhibited by their inhibitors in vitro The translation of these findings into in vivo efficacy requires further adjustment of treatment regimens using sorafenib tosylate or, possibly, other kinase inhibitors.

Efficiency of flubendazole-loaded mPEG-PCL nanoparticles: A promising formulation against the protoscoleces and cysts of Echinococcus granulosus

None of the existing drugs can effectively treat the human cystic echinococcosis. This study aimed to improve the efficacy of flubendazole (FLBZ) against the protoscoleces and cysts of Echinococcus granulosus by preparing polymeric FLBZ-loaded methoxy polyethylene glycol-polycaprolactone (mPEG-PCL) nanoparticles. The protoscoleces and microcysts were treated with FLBZ-loaded mPEG-PCL nanoparticles (FLBZ-loaded nanoparticles) and free FLBZ at the final concentrations of 1, 5, and 10 μg/mL for 27 and 14 days, respectively. The chemoprophylactic efficacy of the drugs was evaluated in experimentally infected mice. The nanoparticles were stable for 1 month, with an average size of 101.41 ± 5.14 nm and a zeta potential of -19.13 ± 2.56 mV. The drug-loading and entrapment efficiency of the FLBZ-loaded nanoparticles were calculated to be 3.08 ± 0.15% and 89.16 ± 2.93%, respectively. The incubation of the protoscoleces with the 10 μg/mL nano-formulation for 15 days resulted in 100% mortality, while after incubation with the 10 μg/mL free FLBZ, the viability rate of the protoscoleces was only 44.0% ± 5.22%. Destruction of the microcysts was observed after 7 days' exposure to the FLBZ-loaded nanoparticles at a concentration of 10 μg/mL. The in vivo challenge showed a significant reduction in the weight and number of the cysts (P <  0.05) in the mice treated with the FLBZ-loaded nanoparticles, yielding efficacy rates of 94.64% and 70.21%, correspondingly. Transmission electron microscopy revealed extensive ultrastructural damage to the cysts treated with the FLBZ-loaded nanoparticles. The results indicated that the FLBZ-loaded nanoparticles were more effective than the free FLBZ against the protoscoleces and cysts of E. granulosus both in vitro and in vivo.

Progress in the pharmacological treatment of human cystic and alveolar echinococcosis: Compounds and therapeutic targets

Human cystic and alveolar echinococcosis are helmintic zoonotic diseases caused by infections with the larval stages of the cestode parasites Echinococcus granulosus and E. multilocularis, respectively. Both diseases are progressive and chronic, and often fatal if left unattended for E. multilocularis. As a treatment approach, chemotherapy against these orphan and neglected diseases has been available for more than 40 years. However, drug options were limited to the benzimidazoles albendazole and mebendazole, the only chemical compounds currently licensed for treatment in humans. To compensate this therapeutic shortfall, new treatment alternatives are urgently needed, including the identification, development, and assessment of novel compound classes and drug targets. Here is presented a thorough overview of the range of compounds that have been tested against E. granulosus and E. multilocularis in recent years, including in vitro and in vivo data on their mode of action, dosage, administration regimen, therapeutic outcomes, and associated clinical symptoms. Drugs covered included albendazole, mebendazole, and other members of the benzimidazole family and their derivatives, including improved formulations and combined therapies with other biocidal agents. Chemically synthetized molecules previously known to be effective against other infectious and non-infectious conditions such as anti-virals, antibiotics, anti-parasites, anti-mycotics, and anti-neoplastics are addressed. In view of their increasing relevance, natural occurring compounds derived from plant and fungal extracts are also discussed. Special attention has been paid to the recent application of genomic science on drug discovery and clinical medicine, particularly through the identification of small inhibitor molecules tackling key metabolic enzymes or signalling pathways.

Human cystic and alveolar echinococcosis (CE and AE), caused by the larval stages of the helminths Echinococcus granulosus and E. multilocularis, respectively, are progressive and chronic diseases affecting more than 1 million people worldwide. Both are considered orphan and neglected diseases by the World Health Organization. As a treatment approach, chemotherapy is limited to the use of benzimidazoles, drugs that stop parasite growth but do not kill the parasite. To compensate this therapeutic shortfall, new treatment alternatives are urgently needed. Here, we present the state-of-the-art regarding the alternative compounds and new formulations of benzimidazoles assayed against these diseases until now. Some of these new and modified compounds, either alone or in combination, could represent a step forward in the treatment of CE and AE. Unfortunately, few compounds have reached clinical trials stage in humans and, when assayed, the design of these studies has not allowed evidence-based conclusions. Thus, there is still an urgent need for defining new compounds or improved formulations of those already assayed, and also for a careful design of clinical protocols that could lead to the draw of a broad international consensus on the use of a defined drug, or a combination of drugs, for the effective treatment of CE and AE.

In vitro and in vivo effects of chitosan-praziquantel and chitosan-albendazole nanoparticles on Echinococcus granulosus Metacestodes

Cystic echinococcosis (CE), which is caused by the metacestode of Echinococcus granulosus, is one of the most important zoonoses affecting humans. Benzimidazoles (in particular albendazole) and praziquantel (PZQ) are effective against CE, but poor water solubility of these agents often leads to inadequate results. Here, we evaluate the effects of chitosan-albendazole (ChABZ) and chitosan-praziquantel (ChPZQ) nanoparticles as a new formulation on hydatid cysts both in vitro and in vivo. Developed microcysts in culture were treated with different concentrations of ChABZ and ChPZQ nanoparticles (either alone or in combination), and ABZ + PZQ suspension. The viability rate of microcysts was used to evaluate the drug efficacies. In addition, the prophylactic and therapeutic effects of the drugs were studied on infected DBA/2 mice. Transmission electron microscopy was used to observe the ultra-structural changes. The viability rate of microcysts and differences in cyst weights were compared by ANOVA, and the cyst numbers were compared using the Kruskal-Wallis test. The combination of ChABZ + ChPZQ nanoparticles was more effective than the ABZ + PZQ suspension in vitro (p < 0.05). In prophylaxy, a significant reduction was observed both in size and in number of the cysts in ChABZ + ChPZQ nanoparticle groups compared with the control group (p < 0.05). In the therapeutic stage, however, this treatment only reduced the cyst numbers. Degeneration of the microcysts treated with the drugs was evident in the ultra-structural imaging. Overall, the nanoparticulate drugs were more effective than their suspension counterparts, but further studies are recommended to evaluate the full potential of these nanoparticles in the treatment of human CE.

Solid lipid nanoparticles and nanostructured lipid carriers as novel drug delivery systems: applications, advantages and disadvantages

During the recent years, more attentions have been focused on lipid base drug delivery system to overcome some limitations of conventional formulations. Among these delivery systems solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) are promising delivery systems due to the ease of manufacturing processes, scale up capability, biocompatibility, and also biodegradability of formulation constituents and many other advantages which could be related to specific route of administration or nature of the materials are to be loaded to these delivery systems. The aim of this article is to review the advantages and limitations of these delivery systems based on the route of administration and to emphasis the effectiveness of such formulations.

Nanoformulations of albendazole as effective anticancer and antiparasite agents

Initially emerging as a widely used clinical antiparasitic drug, albendazole (ABZ) has been increasingly recognized as an effective anticancer agent due to its outstanding advantage, in other words, low toxicity to normal cells but high effectiveness against parasites and some tumors. The major challenge is its poor water solubility and subsequently low bioavailability. This article thus first reviews the brief achievements in using ABZ to treat parasites and cancers, and summarizes the basic mechanisms of action of ABZ. Then this article critically reviews recent nanotechnological strategies, in other words, formulating/conjugating it with carriers into nanoformulations, in practices of improving aqueous solubility and efficacy in treatment of tumors and parasites. Our expert opinions in this field are provided for more effective delivery of ABZ to treat tumors and parasites in vivo.

In vitro and in vivo antihydatid activity of a nano emulsion of Zataria multiflora essential oil

In in vitro process of this study, protoscoleces of the hydatid cysts were exposed to two concentrations of nano emulsion (NE) of Zataria multiflora essential oil (ZMEO) (1 and 2mg/mL) for 10 and 20min. Viability of protoscoleces was confirmed using 0.1% eosin staining. For in vivo studies, sixteen laboratory mice were infected intraperitoneally by 1500 live protoscoleces. Five months after infection, the infected mice were divided into treatment and control groups. The mice of treatment group received the NE of ZMEO (20mg/kg) orally via their drinking water while the mice of control group received no treatment. Two months after the start of treatment, all of the mice were necropsied and the hydatid cysts were collected. Subsequently, the numbers, sizes and weights of the collected cysts were compared between the mice of two groups. The results of in vitro scolicidal assays showed that the scolicidal power of NE of a ZMEO at concentration of 1mg/mL was 88.01%, and 100% after 10 and 20min respectively. NE of ZMEO showed 100% scolicidal power at a concentration of 2mg/mL after 10min (comparing to 4.46% for the control group). The results of in vivo studies revealed that the size of the largest cysts as well as the total number of the cysts were significantly lower in the mice treated with NE of ZMEO (P<0.05). In conclusion, NE of ZMEO may be considered as a natural scolicidal agent and a potential therapeutic tool for treatment of hydatid disease.

In vivo evaluation of the efficacy of combined albedazole-IFN-α treatment for cystic echinococcosis in mice

Cystic echinococcosis (CE) is a serious helminthic zoonosis caused by Echinococcus granulosus metacestode worldwide. The current chemotherapy of CE is mainly based on albendazole (ABZ). However, more than 20% CE cases failed to such chemotherapy. Thus, novel and more efficient treatment options are urgently needed. This study was to evaluate the in vivo efficacy of combined ABZ-interferon (IFN)-α treatment for CE in mice. After 5 months of secondary infection with protoscoleces, mice were randomly allocated into four groups: ABZ-treated group, IFN-α-treated group, ABZ+IFN-α group, and untreated control group. Drugs in diverse treated groups were respectively administered for 2 months. Mice were then euthanized and associated indications were investigated to evaluate the therapeutic efficacy. ABZ+IFN-α induced a significant reduction of the number, size, as well as weight of cysts, compared with that in the ABZ (p < 0.05) or untreated group (p < 0.01), respectively. This effect was associated with ultrastructural modification of the cyst in the ABZ+IFN-α group. Interestingly, significant decrease of IL (interleukin)-10 in serum and in vitro production by spleen cells with ABZ+IFN-α treatment was observed in comparison with untreated control (p < 0.01). Serum IgE, IgG, and subsets were respectively decreased in ABZ+IFN-α treatment, compared with that in the control group (p < 0.01). In conclusion, our findings demonstrated that combination of ABZ with IFN-α may contribute to an efficient therapeutic regimen of human and animal CE.

In vitro and ex vivo activity of Melaleuca alternifolia against protoscoleces of Echinococcus ortleppi

Cystic echinococcosis is a zoonotic disease of difficult diagnosis and treatment. The use of protoscolicidal agents in procedures is of utmost importance for treatment success. This study was aimed at analysing the in vitro and ex vivo activity of Melaleuca alternifolia oil (tea tree oil - TTO), its nanoemulsion formulation (NE-TTO) and its major component (terpinen-4-ol) against Echinococcus ortleppi protoscoleces obtained from cattle. Concentrations of 2·5, 5 and 10 mg mL-1 of TTO, 10 mg mL-1 of NE-TTO and 1, 1·5 and 2 mg mL-1 of terpinen-4-ol were evaluated in vitro against protoscoleces at 5, 10, 15 and 30 min. TTO was also injected directly into hydatid cysts (ex vivo analysis, n = 20) and the viability of protoscoleces was evaluated at 5, 15 and 30 min. The results indicated protoscolicidal effect at all tested formulations and concentrations. Terpinen-4-ol (2 mg mL-1) activity was superior when compared with the highest concentration of TTO. NE-TTO reached a gradual protoscolicidal effect. TTO at 20 mg mL-1 showed 90% protoscolicidal action in hydatid cysts at 5 min. The results showed that TTO affects the viability of E. ortleppi protoscoleces, suggesting a new protoscolicidal option to the treatment of cystic equinococcosis.

Elucidating the influence of praziquantel nanosuspensions on the in vivo metabolism of Taenia crassiceps cysticerci

The aim of this work was to develop nanosuspensions of praziquantel (PZQ) and to evaluate their influence on the energetic metabolism of cysticerci inoculated in BALB/c mice. We analyzed metabolic alterations of glycolytic pathways and the tricarboxylic acid cycle in the parasite. The nanosuspensions were prepared by precipitation and polyvinyl alcohol (PVA), poloxamer 188 (P188) and poloxamer 407 (P407) were used as stabilizers. Nanosuspension prepared with PVA had a particle size of 100nm, while P188- and P407-based nanosuspensions had particle sizes of 74nm and 285nm, respectively. The zeta potential was -8.1, -8.6, and -13.2 for the formulations stabilized with PVA, P188 and P407, respectively. Treatments of T. crassiceps cysticerci-infected mice resulted in an increase in glycolysis organic acids, and enhanced the partial reversion of the tricarboxylic acid cycle, the urea cycle and the production of ketonic bodies in the parasites when compared to the groups treated with conventional PZQ. These data suggest that PZQ nanosuspensions greatly modified the energetic metabolism of cysticerci in vivo. Moreover, the remarkable metabolic alterations produced by the stabilizers indicate that further studies on nanoformulations are required to find potentially suitable nanomedicines.

Functionalized Benzimidazole Scaffolds: Privileged Heterocycle for Drug Design in Therapeutic Medicine

Benzimidazole derivatives are crucial structural scaffolds found in diverse libraries of biologically active compounds which are therapeutically useful agents in drug discovery and medicinal research. They are structural isosteres of naturally occurring nucleotides, which allows them to interact with the biopolymers of living systems. Hence, there is a need to couple the latest information with the earlier documentations to understand the current status of the benzimidazole nucleus in medicinal chemistry research. This present work unveils the benzimidazole core as a multifunctional nucleus that serves as a resourceful tool of information for synthetic modifications of old existing candidates in order to tackle drug resistance bottlenecks in therapeutic medicine. This manuscript deals with the recent advances in the synthesis of benzimidazole derivatives, the widespread biological activities as well as pharmacokinetic reports. These present them as a toolbox for fighting infectious diseases and also make them excellent candidates for future drug design.