In Vivo Evaluation of an Antibody-Functionalized Lipoidal Nanosystem for Schistosomiasis Intervention

Impact of nanostructured formulations for schistosomiasis treatment: a systematic review of in vivo preclinical evidence

BACKGROUND

Schistosomiasis is a neglected tropical disease caused by Schistosoma sp., and praziquantel (PZQ) is the first-line treatment. However, traditional PZQ formulations have low solubility and fast metabolism, limiting its effectiveness. Thus, nanoparticles have been proposed to improve the bioavailability and efficacy of poorly soluble antischistosomal drugs.

AIMS

This systematic review used in vivo preclinical studies to map the available evidence and compare the efficacy of free PZQ and PZQ-based nanostructured formulations (N-PZQ) for schistosomiasis treatment.

METHODS

PubMed, Embase, Scopus, and Web of Science were searched, and 1186 experimental studies published between 1974 and 2024 were screened. Parasitological, histopathological, pharmacokinetic, and toxicological outcomes were evaluated.

RESULTS

Twelve relevant studies were identified exploring N-PZQ formulations based on liposomes, nanoliposomes, and nanocrystals. N-PZQ demonstrated better therapeutic efficacy than free PZQ, reducing parasite load, modifying oogram profiles, and down-regulating liver granuloma development (number and size). N-PZQ also exhibited improved pharmacokinetic profile, with enhanced bioavailability and longer half-life, as well as reduced toxicity (cytotoxicity, genotoxicity, and hepatotoxicity) compared to free PZQ.

CONCLUSION

PZQ-based nanostructured formulations represent a promising strategy to enhance schistosomiasis treatment by improving chemotherapy efficacy, optimizing antiparasitic responses, pharmacokinetics, and reducing drug toxicity.

An update on proteases and protease inhibitors from trematodes

Trematodes, a class of parasitic flatworms, are responsible for a variety of devastating diseases in humans and animals, with schistosomiasis and fascioliasis being prominent examples. Trematode proteolytic systems involved in the host-parasite interaction have emerged as key contributors to the success of trematodes in establishing and maintaining infections. This review concentrates on diverse proteases and protease inhibitors employed by trematodes and provides an update on recent advances in their molecular-level characterization, with a focus on function, structure, and therapeutic target potential.

Nanotechnological approaches in the treatment of schistosomiasis: an overview

Schistosomiasis causes over 200,000 deaths annually. The current treatment option, praziquantel, presents limitations, including low bioavailability and resistance. In this context, nanoparticles have emerged as a promising option for improving schistosomiasis treatment. Several narrative reviews have been published on this topic. Unfortunately, the lack of clear methodologies presented in these reviews leads to the exclusion of many important studies without apparent justification. This integrative review aims to examine works published in this area with a precise and reproducible method. To achieve this, three databases (i.e., Pubmed, Web of Science, and Scopus) were searched from March 31, 2022, to March 31, 2023. The search results included only original research articles that used nanoparticles smaller than 1 µm in the treatment context. Additionally, a search was conducted in the references of the identified articles to retrieve works that could not be found solely using the original search formula. As a result, 65 articles that met the established criteria were identified. Inorganic and polymeric nanoparticles were the most prevalent nanosystems used. Gold was the primary material used to produce inorganic nanoparticles, while poly(lactic-co-glycolic acid) and chitosan were commonly used to produce polymeric nanoparticles. None of these identified works presented results in the clinical phase. Finally, based on our findings, the outlook appears favorable, as there is a significant diversity of new substances with schistosomicidal potential. However, financial efforts are required to advance these nanoformulations.

In Vivo Evaluation of Praziquantel-Loaded Solid Lipid Nanoparticles against S. mansoni Infection in Preclinical Murine Models

This study aimed to develop and assess the long-term stability of drug-loaded solid lipid nanoparticles (SLNs). The SLNs were designed to extend the release profile, overcome the problems of bioavailability and solubility, investigate toxicity, and improve the antischistosomal efficacy of praziquantel. The aim was pursued using solvent injection co-homogenization techniques to fabricate SLNs in which Compritol ATO 888 and lecithin were used as lipids, and Pluronic F127 (PF127) was used as a stabilizer. The long-term stability effect of the PF127 as a stabilizer on the SLNs was evaluated. Dynamic light scattering (DLS) was used to determine the particle size, stability, and polydispersity. The morphology of the SLNs was examined through the use of transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The chemical properties, as well as the mechanical, thermal, and crystal behaviours of SLNs were evaluated using FTIR, ElastoSens Bio2, XRPD, DSC, and TGA, respectively. SLNs with PF127 depicted an encapsulation efficiency of 71.63% and a drug loading capacity of 11.46%. The in vitro drug release study for SLNs with PF127 showed a cumulative release of 48.08% for the PZQ within 24 h, with a similar release profile for SLNs' suspension after 120 days. DLS, ELS, and optical characterization and stability profiling data indicate that the addition of PF127 as the surfactants provided long-term stability for SLNs. In vitro cell viability and in vivo toxicity evaluation signify the safety of SLNs stabilized with PF127. In conclusion, the parasitological data showed that in S. mansoni-infected mice, a single (250 mg/kg) oral dosage of CLPF-SLNs greatly improved PZQ antischistosomal efficacy both two and four weeks post-infection. Thus, the fabricated CLPF-SLNs demonstrated significant efficiency inthe delivery of PZQ, and hence are a promising therapeutic strategy against schistosomiasis.