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Frontiers in Cellular and Infection... 2018Canine leishmaniosis (CanL) is a vector-borne disease caused by the protozoan () species [syn. . (.) species in the Americas] which is transmitted by the bite of a... (Review)
Review
Canine leishmaniosis (CanL) is a vector-borne disease caused by the protozoan () species [syn. . (.) species in the Americas] which is transmitted by the bite of a female phlebotomine sand fly. This parasitosis is endemic and affect millions of dogs in Asia, the Americas and the Mediterranean basin. Domestic dogs are the main hosts and the main reservoir hosts for human zoonotic leishmaniosis. The outcome of infection is a consequence of intricate interactions between the protozoan and the immunological and genetic background of the host. Clinical manifestations can range from subclinical infection to very severe disease. Early detection of infected dogs, their close surveillance and treatment are essential to control the dissemination of the parasite among other dogs, being also a pivotal element for the control of human zoonotic leishmaniosis. Hence, the identification of biomarkers for the confirmation of infection, disease and determination of an appropriate treatment would represent an important tool to assist clinicians in diagnosis, monitoring and in giving a realistic prognosis to subclinical infected and sick dogs. Here, we review the recent advances in the identification of biomarkers, focusing on those related to parasite exposure, susceptibility to infection and disease development. Markers related to the pathogenesis of the disease and to monitoring the evolution of leishmaniosis and treatment outcome are also summarized. Data emphasizes the complexity of parasite-host interactions and that a single biomarker cannot be used alone for CanL diagnosis or prognosis. Nevertheless, results are encouraging and future research to explore the potential clinical application of biomarkers is warranted.
Topics: Animals; Biomarkers; Diagnostic Tests, Routine; Dog Diseases; Dogs; Drug Monitoring; Host-Pathogen Interactions; Leishmania infantum; Leishmaniasis, Visceral
PubMed: 30237985
DOI: 10.3389/fcimb.2018.00302 -
Turkiye Parazitolojii Dergisi Jun 2021This study aimed to determine the differences between the gene expression profiles of and promastigotes through comparative analysis of gene expressions. (Comparative Study)
Comparative Study
OBJECTIVE
This study aimed to determine the differences between the gene expression profiles of and promastigotes through comparative analysis of gene expressions.
METHODS
Cell culture of (MHOM/IL/80) and (MHOM/MA/67/ITMAP/263) cell lines was performed. Afterwards, total RNA isolation and cDNA synthesis were performed and fold changes in the expression levels of 30 genes that play a role in metabolic pathways and nucleic acid synthesis and co-expressed in two species were evaluated by reverse transcriptase polymerase chain reaction. Functions of genes were determined using LeishDB and KEGG databases.
RESULTS
In this study, profiles of protein-coding 30 genes expressed in and promastigotes were evaluated and significant differences were found between the two species (p<0.001). There was a significant fold change in the expression levels of 29% of genes common in the two species. The expression levels of nine genes in were found to be markedly higher than those of (fold change >1). These genes include phosphoglycan beta 1.3 galactosyltransferase-like, lathosterol oxidase-like, fatty acid elongase, 3-oxo-5 alpha-steroid 4-dehydrogenase, calpain-like cysteine peptidase, acetyl-coA synthetase, 3'-nucleotidase/nuclease, 3'-nucleotidase/nuclease precursor and 3-ketoacyl-coA thiolase-like. When the functions of the proteins that correspond to the genes common in the two species were examined in detail using the databases, it was determined that these genes play role in lipid, protein, carbohydrate and nucleic acid metabolic functions of the parasite.
CONCLUSION
Alterations in the expression profiles of genes common to and species may cause differences in the virulence, pathogenesis, clinical features and treatment modality between these parasite species. In addition, evaluation of gene profiles is important in the selection of species-specific or common targets for vaccine and drug studies.
Topics: Animals; Humans; Leishmania infantum; Leishmania major; Life Cycle Stages; Protozoan Proteins; Species Specificity; Transcriptome
PubMed: 34103283
DOI: 10.4274/tpd.galenos.2021.66375 -
PloS One 2015Chemotherapy against visceral leishmaniasis is associated with high toxicity and drug resistance. Leishmania parasites are purine auxotrophs that obtain their purines...
Chemotherapy against visceral leishmaniasis is associated with high toxicity and drug resistance. Leishmania parasites are purine auxotrophs that obtain their purines from exogenous sources. Nucleoside hydrolases release purines from nucleosides and are drug targets for anti-leishmanial drugs, absent in mammal cells. We investigated the substrate specificity of the Leishmania (L.) donovani recombinant nucleoside hydrolase NH36 and the inhibitory effect of the immucillins IA (ImmA), DIA (DADMe-ImmA), DIH (DADMe-ImmH), SMIH (SerMe-ImmH), IH (ImmH), DIG (DADMe-ImmG), SMIG (SerMe-ImmG) and SMIA (SerME-ImmA) on its enzymatic activity. The inhibitory effects of immucillins on the in vitro multiplication of L. (L.) infantum chagasi and L. (L.) amazonensis promastigotes were determined using 0.05-500 μM and, when needed, 0.01-50 nM of each drug. The inhibition on multiplication of L. (L.) infantum chagasi intracellular amastigotes in vitro was assayed using 0.5, 1, 5 and 10 μM of IA, IH and SMIH. The NH36 shows specificity for inosine, guanosine, adenosine, uridine and cytidine with preference for adenosine and inosine. IA, IH, DIH, DIG, SMIH and SMIG immucillins inhibited L. (L.) infantum chagasi and L. (L.) amazonensis promastigote growth in vitro at nanomolar to micromolar concentrations. Promastigote replication was also inhibited in a chemically defined medium without a nucleoside source. Addition of adenosine decreases the immucillin toxicity. IA and IH inhibited the NH36 enzymatic activity (Ki = 0.080 μM for IA and 0.019 μM for IH). IA, IH and SMIH at 10 μM concentration, reduced the in vitro amastigote replication inside mice macrophages by 95% with no apparent effect on macrophage viability. Transmission electron microscopy revealed global alterations and swelling of L. (L.) infantum chagasi promastigotes after treatment with IA and IH while SMIH treatment determined intense cytoplasm vacuolization, enlarged vesicles and altered kinetoplasts. Our results suggest that IA, IH and SMIH may provide new chemotherapy agents for leishmaniasis.
Topics: Adenine; Adenosine; Animals; Antiprotozoal Agents; Cell Proliferation; Enzyme Inhibitors; Female; Humans; In Vitro Techniques; Kinetics; Leishmania infantum; Leishmania mexicana; Leishmaniasis, Cutaneous; Leishmaniasis, Visceral; Mice; Mice, Inbred BALB C; Microscopy, Electron, Transmission; N-Glycosyl Hydrolases; Purine Nucleosides; Pyrimidinones; Pyrroles; Pyrrolidines
PubMed: 25909893
DOI: 10.1371/journal.pone.0124183 -
Journal of Proteomics Sep 2020Leishmania infantum chagasi is the primary etiological agent of visceral leishmaniasis in Latin America, a lethal disease that afflicts hundreds of thousands of people...
Leishmania infantum chagasi is the primary etiological agent of visceral leishmaniasis in Latin America, a lethal disease that afflicts hundreds of thousands of people worldwide every year. Previous studies have shown that the parasite releases microvesicles known as exosomes, which prolong and exacerbate infection in the vertebrate vector. However, little is known of their role in the insect vector, the sand fly Lutzomyia longipalpis. Exosomes were isolated from cultured L. i. chagasi in logarithmic (procyclic) (LOG) and stationary phase (metacyclic-like) (STAT) growth stages, which are the parasite stages found in the vector, and submitted to proteomic analysis. Our studies showed that exosomes from LOG and STAT L. i. chagasi display discrete protein profiles. The presence of approximately 50 known virulence factors was detected, including molecules for immunomodulation and evasion (GP63, EF1α, Oligopeptidase), increased pathogenicity (Casein kinase, KMP-11, Cysteine Peptidase and BiP) and parasite protection (Peroxidoxin). Additionally, the majority of ontological terms were associated with both exosome phases, and no substantial ontological enrichment was observed associated with any of the two exosomal stages. We demonstrated that LOG exosomes show a marked increase in protein number and abundance, including many virulence factors, compared to STAT L. i. chagasi exosomes. SIGNIFICANCE: The knowledge of the role of Leishmania exosomes on leishmaniasis opened up a new world of potential and complexity regarding our understanding of the disease. In Brazil the majority of visceral leishmaniasis cases are caused by the parasite Leishmania infantum chagasi and transmitted by the vector Lutzomyia longipalpis. While Leishmania exosomes were found to play an active role in the mammalian host, little is understood about their effects on the sand fly, or how they might impact on the insect infection by the parasite. For this reason, we isolated exosomes from two developmental stages of L. i. chagasi that occur within the insect with a view to identifying and describing the alterations they undergo. We have identified many hundreds of proteins within both exosome phases and have developed a structure by which to examine potential candidates. Our findings regarding the composition of the exosome proteome raise many questions regarding their function and provide compelling evidence that exosomes play an active role in the parasite's development within the sand fly.
Topics: Animals; Brazil; Exosomes; Leishmania infantum; Leishmaniasis, Visceral; Proteomics; Psychodidae
PubMed: 32673755
DOI: 10.1016/j.jprot.2020.103902 -
PLoS Neglected Tropical Diseases Mar 2020Phlebotomus (Larroussius) perniciosus and Canis familiaris are respectively the only confirmed vector and reservoir for the transmission of Leishmania (L.) infantum...
BACKGROUND
Phlebotomus (Larroussius) perniciosus and Canis familiaris are respectively the only confirmed vector and reservoir for the transmission of Leishmania (L.) infantum MON-1 in Tunisia. However, the vector and reservoir hosts of the two other zymodemes, MON-24 and MON-80, are still unknown. The aim of this study was to analyze the L. infantum life cycle in a Tunisian leishmaniasis focus. For this purpose, we have focused on: i) the detection, quantification and identification of Leishmania among this sand fly population, and ii) the analysis of the blood meal preferences of Larroussius (Lar.) subgenus sand flies to identify the potential reservoirs.
METHODOLOGY AND FINDINGS
A total of 3,831 sand flies were collected in seven locations from the center of Tunisia affected by human visceral leishmaniasis. The collected sand flies belonged to two genus Phlebotomus (Ph.) (five species) and Sergentomyia (four species). From the collected 1,029 Lar. subgenus female sand flies, 8.26% was positive to Leishmania by ITS1 nested PCR. Three Leishmania spp. were identified: L. infantum 28% (24/85), L. killicki 13% (11/85), and L. major 22% (19/85). To identify the blood meal sources in Ph. Lar. subgenus sand flies, engorged females were analyzed by PCR-sequencing targeting the vertebrate cytochrome b gene. Among the 177 analyzed blood-fed females, 169 samples were positive. Sequencing results showed seven blood sources: cattle, human, sheep, chicken, goat, donkey, and turkey. In addition, mixed blood meals were detected in twelve cases. Leishmania DNA was found in 21 engorged females, with a wide range of blood meal sources: cattle, chicken, goat, chicken/cattle, chicken/sheep, chicken/turkey and human/cattle. The parasite load was quantified in fed and unfed infected sand flies using a real time PCR targeting kinetoplast DNA. The average parasite load was 1,174 parasites/reaction and 90 parasites/reaction in unfed and fed flies, respectively.
CONCLUSION
Our results support the role of Ph. longicuspis, Ph. perfiliewi, and Ph. perniciosus in L. infantum transmission. Furthermore, these species could be involved in L. major and L. killicki life cycles. The combination of the parasite detection and the blood meal analysis in this study highlights the incrimination of the identified vertebrate in Leishmania transmission. In addition, we quantify for the first time the parasite load in naturally infected sand flies caught in Tunisia. These findings are relevant for a better understanding of L. infantum transmission cycle in the country. Further investigations and control measures are needed to manage L. infantum transmission and its spreading.
Topics: Animals; DNA; DNA Fingerprinting; DNA, Ribosomal Spacer; Disease Transmission, Infectious; Feeding Behavior; Female; Gastrointestinal Contents; Host Specificity; Humans; Leishmania infantum; Male; Phlebotomus; Polymerase Chain Reaction; Sequence Analysis, DNA; Tunisia
PubMed: 32214313
DOI: 10.1371/journal.pntd.0008077 -
Medicinal Chemistry (Shariqah (United... 2022Leishmaniasis is a worldwide health problem, highly endemic in developing countries. Among the four main clinical forms of the disease, visceral leishmaniasis is the...
BACKGROUND
Leishmaniasis is a worldwide health problem, highly endemic in developing countries. Among the four main clinical forms of the disease, visceral leishmaniasis is the most severe, fatal in 95% of cases. The undesired side-effects from first-line chemotherapy and the reported drug resistance search for effective drugs that can replace or supplement those currently used in an urgent need. Aminoguanidine hydrazones (AGH's) have been explored for exhibiting a diverse spectrum of biological activities, in particular the antileishmanial activity of MGBG. The bioisosteres thiosemicarbazones (TSC's) offer a similar biological activity diversity, including antiprotozoal effects against Leishmania species and Trypanosoma cruzi.
OBJECTIVES
Considering the impact of leishmaniasis worldwide, this work aimed to design, synthesize, and perform a screening upon L. chagasi amastigotes and for the cytotoxicity of the small "inhouse" library of both AGH and TSC derivatives and their structurally-related compounds.
METHODS
A set of AGH's (3-7), TSC's (9, 10), and semicarbazones (11) were initially synthesized. Subsequently, different semi-constrained analogs were designed and also prepared, including thiazolidines (12), dihydrothiazines (13), imidazolines (15), pyrimidines (16, 18) azines (19, 20), and benzotriazepinones (23-25). All intermediates and target compounds were obtained with satisfactory yields and exhibited spectral data consistent with their structures. All final compounds were evaluated against L. chagasi amastigotes and J774.A1 cell line. Molecular docking was performed towards trypanothione reductase using GOLD software.
RESULTS
The AGH's 3i, 4a, and 5d, and the TSC's 9i, 9k, and 9o were selected as valuable hits. These compounds presented antileishmanial activity compared with pentamidine, showing ICvalues ranged from 0.6 to 7.27 μM, maximal effects up to 55.3%, and satisfactory SI values (ranged from 11 to 87). On the other hand, most of the resulting semi-constrained analogs were found cytotoxic or presented reduced antileishmanial activity. In general, TSC class is more promising than its isosteric AGH analogs, and the beneficial aromatic substituent effects are not similar in both series. In silico studies have suggested that these hits are capable of inhibiting the trypanothione reductase from the amastigote forms.
CONCLUSION
The promising antileishmanial activity of three AGH's and three TSC's was characterized. These compounds presented antileishmanial activity compared with PTD, showing IC50 values ranged from 0.6 to 7.27 μM, and satisfactory SI values. Further pharmacological assays involving other Leishmania strains are in progress, which will help choose the best hits for in vivo experiments.
Topics: Guanidines; Hydrazones; Leishmania infantum; Molecular Docking Simulation; Structure-Activity Relationship; Thiosemicarbazones
PubMed: 33593264
DOI: 10.2174/1573406417666210216154428 -
Drugs Nov 2013Visceral leishmaniasis (VL), also known as Kala-Azar, is a disseminated protozoal infection caused principally by Leishmania donovani and Leishmania infantum (known as... (Review)
Review
Visceral leishmaniasis (VL), also known as Kala-Azar, is a disseminated protozoal infection caused principally by Leishmania donovani and Leishmania infantum (known as Leishmania chagasi in South America). The therapeutic options for VL are diverse and depend on different factors, such as the geographical area of the infection, development of resistance to habitual treatments, HIV co-infection, malnourishment and other concomitant infections. This article provides an exhaustive review of the literature regarding studies published on the treatment of VL, and gives therapeutic recommendations stratified according to their level of evidence, the species of Leishmania implicated and the geographical location of the infection.
Topics: Antiprotozoal Agents; Drug Resistance; HIV Infections; Humans; Leishmania donovani; Leishmania infantum; Leishmaniasis, Visceral; Malnutrition
PubMed: 24170666
DOI: 10.1007/s40265-013-0133-0 -
Genes Apr 2022Abrupt environmental changes are faced by parasites during transmission from a poikilothermic insect vector to a warm-blooded host. Adaptation to harsh environmental... (Review)
Review
Abrupt environmental changes are faced by parasites during transmission from a poikilothermic insect vector to a warm-blooded host. Adaptation to harsh environmental conditions, such as nutrient deprivation, hypoxia, oxidative stress and heat shock needs to be accomplished by rapid reconfiguration of gene expression and remodeling of protein interaction networks. Chaperones play a central role in the maintenance of cellular homeostasis, and they are responsible for crucial tasks such as correct folding of nascent proteins, protein translocation across different subcellular compartments, avoiding protein aggregates and elimination of damaged proteins. Nearly one percent of the gene content in the genome corresponds to members of the HSP40 family, a group of proteins that assist HSP70s in a variety of cellular functions. Despite their expected relevance in the parasite biology and infectivity, little is known about their functions or partnership with the different HSP70s. Here, we summarize the structural features of the 72 HSP40 proteins encoded in the genome and their classification into four categories. A review of proteomic data, together with orthology analyses, allow us to postulate cellular locations and possible functional roles for some of them. A detailed study of the members of this family would provide valuable information and opportunities for drug discovery and improvement of current treatments against leishmaniasis.
Topics: HSP40 Heat-Shock Proteins; HSP70 Heat-Shock Proteins; Leishmania infantum; Molecular Chaperones; Proteomics
PubMed: 35627127
DOI: 10.3390/genes13050742 -
Frontiers in Immunology 2022In this study we explored the previously established leishmanicidal activity of a complementary set of 24 imidazolium salts (IS), 1-hexadecylimidazole (CIm) and...
In this study we explored the previously established leishmanicidal activity of a complementary set of 24 imidazolium salts (IS), 1-hexadecylimidazole (CIm) and 1-hexadecylpyridinium chloride (CPyrCl) against and . Promastigotes of and were incubated with 0.1 to 100 μM of the compounds and eight of them demonstrated leishmanicidal activity after 48 h - CMImMeS (IC = 11.6), CMImPF(IC = 6.9), CMImBr (IC = 6), CMImCl (IC = 4.1), CMImCl (IC = 1.8), (C)MImCl (IC = 1.9), CIm (IC = 14.6), and CPyrCl (IC = 4).The effect of IS on reactive oxygen species production, mitochondrial membrane potential, membrane integrity and morphological alterations of promastigotes was determined, as well as on -infected macrophages. Their cytotoxicity against macrophages and human erythrocytes was also evaluated. The IS CMImMeS, CMImPF, CMImBr, CMImCl, CMImCl and (C)MImCl, and the compounds CIm and CPyrCl killed and inhibited the growth of promastigote forms of and in a concentration-dependent manner, contributing to a better understanding of the structure-activity relationship of IS against . These IS induced ROS production, mitochondrial dysfunction, membrane disruption and morphological alterations in infective forms of and killed intracellular amastigote forms in very low concentrations (IC ≤ 0.3), being potential drug candidates against .
Topics: Animals; Mice; Humans; Salts; Leishmania mexicana; Antiprotozoal Agents; Mice, Inbred BALB C; Leishmania infantum; Oxidative Stress
PubMed: 36733394
DOI: 10.3389/fimmu.2022.1096312 -
Memorias Do Instituto Oswaldo Cruz Aug 2013Pentavalent antimonials such as meglumine antimoniate (MA) are the primary treatments for leishmaniasis, a complex disease caused by protozoan parasites of the genus...
Pentavalent antimonials such as meglumine antimoniate (MA) are the primary treatments for leishmaniasis, a complex disease caused by protozoan parasites of the genus Leishmania . Despite over 70 years of clinical use, their mechanisms of action, toxicity and pharmacokinetics have not been fully elucidated. Radiotracer studies performed on animals have the potential to play a major role in pharmaceutical development. The aims of this study were to prepare an antimony radiotracer by neutron irradiation of MA and to determine the biodistribution of MA in healthy and Leishmania (Leishmania) infantum chagasi-infected mice. MA (Glucantime®) was neutron irradiated inside the IEA-R1 nuclear reactor, producing two radioisotopes, ¹²²Sb and ¹²⁴Sb, with high radionuclidic purity and good specific activity. This irradiated compound presented anti-leishmanial activity similar to that of non-irradiated MA in both in vitro and in vivo evaluations. In the biodistribution studies, healthy mice showed higher uptake of antimony in the liver than infected mice and elimination occurred primarily through biliary excretion, with a small proportion of the drug excreted by the kidneys. The serum kinetic curve was bi-exponential, with two compartments: the central compartment and another compartment associated with drug excretion. Radiotracers, which can be easily produced by neutron irradiation, were demonstrated to be an interesting tool for answering several questions regarding antimonial pharmacokinetics and chemotherapy.
Topics: Animals; Antimony; Antiprotozoal Agents; Cricetinae; Female; Leishmania infantum; Leishmaniasis; Meglumine; Meglumine Antimoniate; Mice, Inbred BALB C; Organometallic Compounds; Radioisotopes; Radiopharmaceuticals; Time Factors; Tissue Distribution
PubMed: 23903979
DOI: 10.1590/0074-0276108052013014