Metabolomics-based studies in the field of Leishmania /leishmaniasis

Identification of protein profile in metacyclic and amastigote-like stages of Leishmania tropica: a proteomic approach

Leishmaniasis is a tropical disease that leads to various clinical phenotypes. This study aimed to investigate protein expression changes in metacyclic and amastigote-like stages of L. tropica isolated from Iranian cutaneous leishmaniasis patients. Isolated samples were cultured and species type identified using PCR-RFLP technique. The promastigotes were grown in RPMI1640 media and differentiated to metacyclic and amastigote-like forms, followed by the extracted proteins of both successive stages carried out for proteomics and bioinformatics analysis. Using SWATH-MS quantitative proteomics technique, a total 176 and 155 distinct proteins were identified in metacyclic and axenic amastigote stages, respectively. Of these, 65 proteins were altered significantly (p-value < 0.05 and fold change ≥ 2) between studied stages. Several gene ontology (GO) categories were enriched for biological process during conversion of metacyclic promastigotes into amastigote-like, which "metabolic process" (GO: 0044281, P-Value: 6.52e-5), and "translation" (GO: 0006412, p-value: 5.01e-14) were disclosed as the top category in up and down-regulated proteins, respectively. Also, the KEGG pathway analysis indicated "metabolic pathways" and "ribosome" term as the most important pathways in up and down-regulated proteins, respectively. According to protein interaction network analysis, enolase (ENOL) has been detected as main hub proteins during differentiation, followed by Putative NADH-dependent fumarate reductase (LmjF.35.1180) and 40S ribosomal protein S2 (LmjF.32.0450). Overall, protein changes possibly play important roles in L. tropica biology. Anabolic pathways were down-regulated, whereas catabolic pathways were up-regulated during L. tropica differentiation. These protein expression changes could provide parasite survival in host macrophages, and could use as novel potential drug and vaccine targets for leishmaniasis.

The Designing of a Gel Formulation with Chitosan Polymer Using Liposomes as Nanocarriers of Amphotericin B for a Non-invasive Treatment Model of Cutaneous Leishmaniasis

PURPOSE

Leishmaniasis is a disease caused by different Leishmania spp., which are transmitted to humans by a bite of infected female sand flies. Cutaneous leishmaniasis (CL, oriental sore), visceral leishmaniasis (VL), and mucocutaneous leishmaniasis (MCL) are three main clinical forms, however, only CL and VL are seen in Turkey. Cutaneous leishmaniasis is characterized by skin lesion(s) and is one of the most important vector-borne diseases in Turkey with over 2000 cases reported annually in 40 out of 81 provinces. The treatment is usually made invasively and painfully by intralesional injection of pentavalent antimony compounds. Non-invasive and innovative treatment methods are needed as aimed in this study.

METHODS

In the present study, one of the classical antileishmanial drugs, amphotericin B (AmB), encapsulated in liposomes was evaluated using non-invasive design based on chitosan, which is a nontoxic, biocompatible and biodegradable polymer. To avoid the invasive effect of conventional intralesional needle application, the drug was encapsulated in liposomes and incorporated into a chitosan gel for applying topically on the skin lesion. The efficacy of encapsulation of amphotericin B into liposomes and the drug release from liposomes were studied. The chitosan gel was evaluated for viscosity, flowability, appearance and pH. The efficacy of the drug embedded into chitosan gel, liposomal AmB alone and chitosan gel alone in four different concentrations was also tested using Leishmania spp. promastigotes in vitro.

RESULTS

The findings have shown that AmB was encapsulated into the liposomes with high efficiency (86.6%) and long-term physical and chemical stability. Therefore, designed liposomal formulation was suitable for sustained release. The appearance of the drug-embedded chitosan gel was transparent and appropriate. Chitosan gels showed non- Newtonian behavior and plastic flow. The liposomal AmB also showed higher efficacy with no parasites in all concentrations while drug embedded into chitosan gel and chitosan gel alone were effective in two higher concentrations. The lower efficacy of the drug-embedded chitosan gel in 24 h in in-vitro study was probably due to slow release of the drug.

CONCLUSION

The gel design created in this study will provide ease of use for the lesions of CL patients that do not have a specific number, size, and shape. Follow-up studies by the ex-vivo macrophage infection model with Leishmania intracellular amastigote forms and Leishmania-infected animal models are needed to understand the present design's efficacy better.

Trypanosoma brucei: Metabolomics for analysis of cellular metabolism and drug discovery

BACKGROUND

Trypanosoma brucei is the causative agent of Human African Trypanosomiasis (also known as sleeping sickness), a disease causing serious neurological disorders and fatal if left untreated. Due to its lethal pathogenicity, a variety of treatments have been developed over the years, but which have some important limitations such as acute toxicity and parasite resistance. Metabolomics is an innovative tool used to better understand the parasite's cellular metabolism, and identify new potential targets, modes of action and resistance mechanisms. The metabolomic approach is mainly associated with robust analytical techniques, such as NMR and Mass Spectrometry. Applying these tools to the trypanosome parasite is, thus, useful for providing new insights into the sleeping sickness pathology and guidance towards innovative treatments.

AIM OF REVIEW

The present review aims to comprehensively describe the T. brucei biology and identify targets for new or commercialized antitrypanosomal drugs. Recent metabolomic applications to provide a deeper knowledge about the mechanisms of action of drugs or potential drugs against T. brucei are highlighted. Additionally, the advantages of metabolomics, alone or combined with other methods, are discussed.

KEY SCIENTIFIC CONCEPTS OF REVIEW

Compared to other parasites, only few studies employing metabolomics have to date been reported on Trypanosoma brucei. Published metabolic studies, treatments and modes of action are discussed. The main interest is to evaluate the metabolomics contribution to the understanding of T. brucei's metabolism.

Cutaneous leishmaniasis: multiomics approaches to unravel the role of immune cells checkpoints

INTRODUCTION

Cutaneous leishmaniasis (CL) is the most frequent form of leishmaniases, associated with skin inflammation and ulceration. Understanding the interaction of different phagocytic cells in the recognition and uptake of different Leishmania species is critical for controlling the infection. Phagocytic cells have a pivotal role as professional antigen-presenting cells that bridge the innate and adaptive immunity and shape the outcome of the disease.

AREAS COVERED

Here we reviewed new technologies with high-throughput data collection capabilities along with systems biology approaches which are recently being used to decode the paradox of CL immunology.

EXPERT OPINION

We emphasized on the crosstalk between DC and T-cells while focusing on the immune checkpoints interactions between the human immune system and the Leishmania species. Further, we discussed omics technologies including bulk RNA sequencing, reverse transcriptase-multiplex ligation dependent probe amplification (RT-MLPA), and proximity extension assay (PEA) in studies on human blood or tissue-driven samples from CL patients in which we have so far been involved.

Multi Platforms Strategies and Metabolomics Approaches for the Investigation of Comprehensive Metabolite Profile in Dogs with Babesia canis Infection

Canine babesiosis is an important tick-borne disease worldwide, caused by parasites of the Babesia genus. Although the disease process primarily affects erythrocytes, it may also have multisystemic consequences. The goal of this study was to explore and characterize the serum metabolome, by identifying potential metabolites and metabolic pathways in dogs naturally infected with Babesia canis using liquid and gas chromatography coupled to mass spectrometry. The study included 12 dogs naturally infected with B. canis and 12 healthy dogs. By combining three different analytical platforms using untargeted and targeted approaches, 295 metabolites were detected. The untargeted ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) metabolomics approach identified 64 metabolites, the targeted UHPLC-MS/MS metabolomics approach identified 205 metabolites, and the GC-MS metabolomics approach identified 26 metabolites. Biological functions of differentially abundant metabolites indicate the involvement of various pathways in canine babesiosis including the following: glutathione metabolism; alanine, aspartate, and glutamate metabolism; glyoxylate and dicarboxylate metabolism; cysteine and methionine metabolism; and phenylalanine, tyrosine, and tryptophan biosynthesis. This study confirmed that host–pathogen interactions could be studied by metabolomics to assess chemical changes in the host, such that the differences in serum metabolome between dogs with B. canis infection and healthy dogs can be detected with liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS) methods. Our study provides novel insight into pathophysiological mechanisms of B. canis infection.

Glucantime-loaded electrospun core-shell nanofibers composed of poly(ethylene oxide)/gelatin-poly(vinyl alcohol)/chitosan as dressing for cutaneous leishmaniasis

Leishmaniasis, one of the main concerns of the World Health Organization, is a parasitic disease caused by Leishmania species. The main objective of this study was to prepare a topical drug delivery system that can deliver glucantime to the site of cutaneous Leishmania wounds. Using the electrospinning method, a core-shell nanofibrous mat composed of macromolecules including polyethylene oxide, gelatin, poly (vinyl alcohol) and chitosan was prepared. The prepared nanofibers were characterized by scanning electron microscopy (SEM), transmission electron microscopy, Fourier transform infrared spectroscopy (FT-IR), tensile test and in vitro drug release test. The anti-Leishmania activities of drug-loaded nanofibers against Leishmania promastigotes and its cytotoxicity on fibroblasts were determined respectively by flow-cytometry and indirect MTT methods. Results of morphological studies showed that uniform nanofibers were prepared without any bead with average diameter of 404 nm. The TEM investigation confirmed the core-shell structure of the fibers. The in-vitro drug release assay was executed using Franz diffusion cell, which indicted 84% of glucantime was released during the first 9 h. The results indicated that 4 and 6 cm² of nanofibers mat were significantly killed promatigotes up to 78%. Moreover, the MTT assay also showed that the fabricated nanofibers do not possess any cytotoxicity towards fibroblast cells.

A quantitative proteomic and bioinformatics analysis of proteins in metacyclogenesis of Leishmania tropica

Recently there has a growing interest in MS-based analysis on Leishmania for biology study, host-parasite interaction and drug target discovery. The aims of this study were to analyzed protein profiles in the procyclic and metacyclic stages of L. tropica, and investigate their potential role in metacyclogenesis molecular mechanisms. Sequential window acquisition of all theoretical fragment ion spectra mass spectrometry (SWATH-MS) analysis was used to analyze protein profiles in each of procyclic and metacyclic stages. Proteins with a fold change>2 or <0.5 and p < 0.05 were considered to be significantly differentially expressed proteins (DEPs). The DEPs were subjected to gene ontology (GO), KEGG pathway and network analysis using PANTHER and STRING database, respectively. Quantitative real-time PCR of six selected genes validated the proteomic data. We quantified a total of 352 proteins in procyclic and metacyclic cells and 56 differentially expressed proteins (27 up/ 29down-regulated in metacyclic compared to procyclic). On the basis of biological processes in GO, the DEPs were primarily involved in ``metabolic process'' (GO: 0008152) and ``cellular process'' (GO: 0009987). In addition, several enriched GO terms were identified via molecular function, which among them ``catalytic activity'' (GO: 0003824) and ``binding'' (GO: 0005488) were disclosed as top category. The KEGG pathway analysis indicated ``metabolic pathways'' (p-value: 3.80E-08) including 17 genes term as the top pathway in DEPs. These findings bring a new insight in our understanding of the molecular characterization of metacyclogenesis and infective form in L. tropica. Comparative analysis of the proteome of both developmental stages of the L. tropica would help to the identification of proteins candidates for the development of new potential drug targets and vaccines.

Gestational Diabetes Mellitus Regulatory Network Identifies hsa-miR-145-5p and hsa-miR-875-5p as Potential Biomarkers

BACKGROUND

Gestational diabetes mellitus (GDM) is pregnancy-related diabetes with vital risks for both mother and the fetus. Molecular studies represent one of the popular approaches for investigating mechanisms associated with the disease nature. One of which is through interaction network analysis via Cytoscape V. 3.6.1.

METHODS

In this study, the microRNA (miRNA) expression array of GSE98043 from gene expression omnibus (GEO) database was retrieved and screened. We identified 12 differentially expressed (DE) miRNAs (P ≤ 0.05) and nine target hub-bottleneck genes (disease score > 1) for GDM based on miRNA-target interactions created via plugin ClueGO + Cluepedia + STRING.

RESULTS

MiRNA-target information showed that the miRNAs are mostly up-regulated and hsa-miR-145-5p and hsa-miR-875-5p targets the most genes. Among target genes, IL6, GCG, APOB, and ALB have the highest associations with DE-miRNAs. Gene ontology analysis based on biological processes identification via ClueGO + CluePedia, in addition, showed that target hub-bottlenecks are mainly related to metabolism functions and any changes in this regulatory network could impose fundamental alterations in these processes.

CONCLUSIONS

It can be concluded that via these introduced miRNAs and their targets, the molecular tests for diagnosis and treatment of GDM can be improved after applying validation approaches.