High genome plasticity and frequent genetic exchange in Leishmania tropica isolates from Afghanistan, Iran and Syria

Background The kinetoplastid protozoan Leishmania tropica mainly causes cutaneous leishmaniasis in humans in the Middle East, and relapse or treatment failure after treatment are common in this area. L. tropica’s digenic life cycle includes distinct stages in the vector sandfly and the mammalian host. Sexual reproduction and genetic exchange appear to occur more frequently than in other Leishmania species. Understanding these processes is complicated by chromosome instability during cell division that yields aneuploidy, recombination and heterozygosity. This combination of rare recombination and aneuploid permits may reveal signs of hypothetical parasexual mating, where diploid cells fuse to form a transient tetraploid that undergoes chromosomal recombination and gradual chromosomal loss. Methodology/principal findings The genome-wide SNP diversity from 22 L. tropica isolates showed chromosome-specific runs of patchy heterozygosity and extensive chromosome copy number variation. All these isolates were collected during 2007–2017 in Sweden from patients infected in the Middle East and included isolates from a patient possessing two genetically distinct leishmaniasis infections three years apart with no evidence of re-infection. We found differing ancestries on the same chromosome (chr36) across multiple samples: matching the reference genome with few derived alleles, followed by blocks of heterozygous SNPs, and then by clusters of homozygous SNPs with specific recombination breakpoints at an inferred origin of replication. Other chromosomes had similar marked changes in heterozygosity at strand-switch regions separating polycistronic transcriptional units. Conclusion/significance These large-scale intra- and inter-chromosomal changes in diversity driven by recombination and aneuploidy suggest multiple mechanisms of cell reproduction and diversification in L. tropica, including mitotic, meiotic and parasexual processes. It underpins the need for more genomic surveillance of Leishmania, to detect emerging hybrids that could spread more widely and to better understand the association between genetic variation and treatment outcome. Furthering our understanding of Leishmania genome evolution and ancestry will aid better diagnostics and treatment for cutaneous leishmaniasis caused by L.tropica in the Middle East.

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High genome plasticity and frequent genetic exchange in Leishmania tropica isolates from Afghanistan, Iran and Syria

10.1101/2021.08.02.453096 ◽

2021 ◽

Author(s):

Hedvig Glans ◽

Maria Lind Karlberg ◽

Reza Advani ◽

Maria Bradley ◽

Erik Alm ◽

...

Keyword(s):

Middle East ◽

Cutaneous Leishmaniasis ◽

Large Scale ◽

Chromosome Instability ◽

Leishmania Species ◽

Genetic Exchange ◽

Mammalian Host ◽

Leishmania Tropica ◽

Chromosomal Changes ◽

Diploid Cells

Background The kinetoplastid protozoan Leishmania tropica mainly causes cutaneous leishmaniasis in humans in the Middle East, and relapse or treatment failure after treatment are common in this area. L. tropica's digenic life cycle includes distinct stages in the vector sandfly and the mammalian host. Sexual reproduction and genetic exchange appear to occur more frequently than in other Leishmania species. Understanding these processes is complicated by chromosome instability during cell division that yields aneuploidy, recombination and heterozygosity. This combination of rare recombination and aneuploid permits may reveal signs of hypothetical parasexual mating, where diploid cells fuse to form a transient tetraploid that undergoes chromosomal recombination and gradual chromosomal loss. Methodology and Findings The genome-wide SNP diversity from 22 L. tropica isolates showed chromosome-specific runs of patchy homozygosity and extensive chromosome copy number variation. All these isolates were collected during 2007-2017 in the Middle East and included isolates from a patient possessing two genetically distinct leishmaniasis infections three years apart with no evidence of re-infection. We found on the same chromosomes (chr36) in different samples ancestries matching the reference genome with few derived alleles, followed by blocks of heterozygous SNPs, and then by clusters of homozygous SNPs with specific recombination breakpoints at the inferred origin of replication. Other chromosomes had similar marked changes in heterozygosity at strand-switch regions separating polycistronic transcriptional units. Conclusion These large-scale intra- and inter-chromosomal changes in diversity driven by recombination and aneuploidy suggest multiple mechanisms of cell reproduction and diversification in L. tropica, including mitotic, meiotic and parasexual processes. It underpins the need for more genomic surveillance of Leishmania, to detect emerging hybrids that could spread more widely and to better understand the association between genetic variation and treatment outcome. Furthering our understanding of Leishmania genome evolution and ancestry will aid better diagnostics and treatment for cutaneous leishmaniasis caused by L.tropica in the Middle East.

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Imported leishmaniasis in Sweden 1993–2016

Epidemiology and Infection ◽

10.1017/s0950268818001309 ◽

2018 ◽

Vol 146 (10) ◽

pp. 1267-1274 ◽

Cited By ~ 8

Author(s):

S. K. Söbirk ◽

M. Inghammar ◽

M. Collin ◽

L. Davidsson

Keyword(s):

Middle East ◽

Laboratory Test ◽

Cutaneous Leishmaniasis ◽

Epidemiological Study ◽

Correct Diagnosis ◽

Leishmania Tropica ◽

Swedish Population ◽

Laboratory Methods ◽

Healthcare Settings ◽

Swedish Patient

AbstractIn Sweden, leishmaniasis is an imported disease and its epidemiology and incidence were not known until now. We conducted a retrospective, nationwide, epidemiological study from 1993 to 2016. Probable cases were patients with leishmaniasis diagnoses reported to the Swedish Patient registry, collecting data on admitted patients in Swedish healthcare since 1993 and out-patient visits since 2001. Confirmed cases were those with a laboratory test positive for leishmaniasis during 1993–2016. 299 probable cases and 182 confirmed cases were identified. Annual incidence ranged from 0.023 to 0.35 per 100 000 with a rapid increase in the last 4 years. Of 182 laboratory-verified cases, 96 were diagnosed from 2013 to 2016, and in this group, almost half of the patients were children under 18 years. Patients presented in different healthcare settings in all regions of Sweden. Cutaneous leishmaniasis was the most common clinical manifestation and the majority of infections were acquired in Asia including the Middle East, specifically Syria and Afghanistan. Leishmania tropica was responsible for the majority of cases (42%). A combination of laboratory methods increased the sensitivity of diagnosis among confirmed cases. In 2016, one-tenth of the Swedish population were born in Leishmania-endemic countries and many Swedes travel to these countries for work or vacation. Swedish residents who have spent time in Leishmania-endemic areas, could be at risk of developing disease some time during their lives. Increased awareness and knowledge are needed for correct diagnosis and management of leishmaniasis in Sweden.

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Large-Scale Phylogenetic Analysis of Trypanosomatid Adenylate Cyclases Reveals Associations with Extracellular Lifestyle and Host–Pathogen Interplay

Genome Biology and Evolution ◽

10.1093/gbe/evaa226 ◽

2020 ◽

Vol 12 (12) ◽

pp. 2403-2416

Author(s):

Ignacio Miguel Durante ◽

Anzhelika Butenko ◽

Vendula Rašková ◽

Arzuv Charyyeva ◽

Michaela Svobodová ◽

...

Keyword(s):

Phylogenetic Analysis ◽

Life Cycle ◽

Large Scale ◽

Expression Profiles ◽

Leishmania Species ◽

Mammalian Host ◽

Insect Vector ◽

Environmental Signals ◽

Life Cycle Stages ◽

Host Life

Abstract Receptor adenylate cyclases (RACs) on the surface of trypanosomatids are important players in the host–parasite interface. They detect still unidentified environmental signals that affect the parasites’ responses to host immune challenge, coordination of social motility, and regulation of cell division. A lesser known class of oxygen-sensing adenylate cyclases (OACs) related to RACs has been lost in trypanosomes and expanded mostly in Leishmania species and related insect-dwelling trypanosomatids. In this work, we have undertaken a large-scale phylogenetic analysis of both classes of adenylate cyclases (ACs) in trypanosomatids and the free-living Bodo saltans. We observe that the expanded RAC repertoire in trypanosomatids with a two-host life cycle is not only associated with an extracellular lifestyle within the vertebrate host, but also with a complex path through the insect vector involving several life cycle stages. In Trypanosoma brucei, RACs are split into two major clades, which significantly differ in their expression profiles in the mammalian host and the insect vector. RACs of the closely related Trypanosoma congolense are intermingled within these two clades, supporting early RAC diversification. Subspecies of T. brucei that have lost the capacity to infect insects exhibit high numbers of pseudogenized RACs, suggesting many of these proteins have become redundant upon the acquisition of a single-host life cycle. OACs appear to be an innovation occurring after the expansion of RACs in trypanosomatids. Endosymbiont-harboring trypanosomatids exhibit a diversification of OACs, whereas these proteins are pseudogenized in Leishmania subgenus Viannia. This analysis sheds light on how ACs have evolved to allow diverse trypanosomatids to occupy multifarious niches and assume various lifestyles.

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Leishmanicidal Activity of Plant Extracts from Sefrou, a Moroccan Focus of Leishmaniasis, against Various Leishmania Parasites in the Promastigote Stage

Phytothérapie ◽

10.3166/phyto-2018-0085 ◽

2018 ◽

Vol 17 (2) ◽

pp. 83-89 ◽

Cited By ~ 1

Author(s):

I. Zeouk ◽

A. Et-Touys ◽

M. Balouiri ◽

H. Fellah ◽

A. El Ouali Lalami ◽

...

Keyword(s):

Cutaneous Leishmaniasis ◽

Plant Extracts ◽

Leishmania Infantum ◽

Leishmania Major ◽

Local Population ◽

Public Health Problem ◽

World Health ◽

Total Phenolic ◽

Leishmania Tropica ◽

Cistus Salviifolius

According to the World Health Organization, leishmaniasis remains a major worldwide public health problem. The province of Sefrou located in the center of Morocco is a focus of cutaneous leishmaniasis. The present study aims at evaluating the antileishmanial potential of Berberis sp.,Crataegus oxyacantha, Cistus salviifolius, Ephedra altissima and Lavandula dentatafrequently used by the local population. Methanolic extracts were tested against the promastigote form ofLeishmania tropica, Leishmania majorandLeishmania infantumusing tetrazolium-based colorimetric (MTT) assay. The total phenol and flavonoids content of all extracts were determined using the Folin–Ciocalteu reagent, aluminum chloride, and potassium acetate solutions respectively. The plant extracts exhibited antileishmanial activity with variability depending on the tested strain and the plant species compared to Glucantime® used as control (IC50 (the half maximal inhibitory concentration) > 1,000 μg/mL). The best inhibition was observed with Berberis sp., againstLeishmania major(IC50 = 394.40 ± 3.02 μg/ml), andEphedra altissima(reported for the first time) againstLeishmania infantum(IC50 = 490.84 ± 3.15 μg/mL).Leishmania tropicahas shown the same sensitivity behavior toward the five extracts (in average IC50 = 540 ± 11.20 μg/mL). The total phenolic content was higher forCrataegus oxyacanthaandCistus salviifolius(140.67 ± 3.17 μg eq Gallic Acid (GA)/ mg of Extract (E) and 133.83 ± 9.03 μg eq GA/mg of E respectively), while flavonoid was higher forCistus salviifoliusandLavandula dentata(57.92 ± 2.46 μg eq Quercetin (Que)/ mg of Extract (E) and 41.53 ± 1.74 μg eq Que/mg of E). All the tested extracts present some promising aspects that may cure cutaneous leishmaniasis in the center of Morocco; further bioguided assays are needed to isolate the fractions and the bioactive molecule.

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Naphthoquinones and derivatives for chemotherapy: perspectives and limitations of their anti-trypanosomatids activities

Current Pharmaceutical Design ◽

10.2174/1381612826666201109111802 ◽

2020 ◽

Vol 26 ◽

Author(s):

Luíza Dantas-Pereira ◽

Edézio F. Cunha-Junior ◽

Valter V. Andrade-Neto ◽

John F. Bower ◽

Guilherme A. M. Jardim ◽

...

Keyword(s):

Large Scale ◽

Neglected Tropical Diseases ◽

Folk Medicine ◽

Leishmania Species ◽

Parasitic Infections ◽

Mechanistic Analysis ◽

Leishmania Spp ◽

Nanomolar Range

: Chagas disease, Sleeping sickness and Leishmaniasis, caused by trypanosomatids Trypanosoma cruzi, Trypanosoma brucei and Leishmania spp., respectively, are considered neglected tropical diseases, and they especially affect impoverished populations in the developing world. The available chemotherapies are very limited and a search for alternatives is still necessary. In folk medicine, natural naphthoquinones have been employed for the treatment of a great variety of illnesses, including parasitic infections. This review is focused on the anti-trypanosomatid activity and mechanistic analysis of naphthoquinones and derivatives. Among all the series of derivatives tested in vitro, naphthoquinone-derived 1,2,3-triazoles were very active on T. cruzi infective forms in blood bank conditions, as well as in amastigotes of Leishmania spp. naphthoquinones containing a CF3 on a phenyl amine ring inhibited T. brucei proliferation in the nanomolar range, and naphthopterocarpanquinones stood out for their activity on a range of Leishmania species. Some of these compounds showed a promising selectivity index (SI) (30 to 1900), supporting further analysis in animal models. Indeed, high toxicity to the host and inactivation by blood components are crucial obstacles to be overcome to use naphthoquinones and/or their derivatives for chemotherapy. Multidisciplinary initiatives embracing medicinal chemistry, bioinformatics, biochemistry, and molecular and cellular biology need to be encouraged to allow the optimization of these compounds. Large scale automated tests are pivotal for the efficiency of the screening step, and subsequent evaluation of both the mechanism of action in vitro and pharmacokinetics in vivo are essential for the development of a novel, specific and safe derivative, minimizing adverse effects.

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A Turbulent Silk Road: China's Vulnerable Foreign Policy in the Middle East and North Africa

The China Quarterly ◽

10.1017/s0305741020001216 ◽

2021 ◽

pp. 1-21

Author(s):

Andrea Ghiselli ◽

Pippa Morgan

Keyword(s):

Middle East ◽

North Africa ◽

Security Policy ◽

Large Scale ◽

Chinese Government ◽

Horn Of Africa ◽

Host Countries ◽

Security Risks ◽

Significant Evidence ◽

Chinese Workers

Abstract The nexus between China's human and economic presence abroad and its security policy is increasingly important. Within this nexus, this study statistically explores whether and to what extent Chinese contractors reduce the number of Chinese nationals they send to work in North Africa, the Middle East and the Horn of Africa when the security situation in host states worsens. We find no significant evidence that either warnings from Chinese embassies and consulates to leave host countries or expert perceptions of host stability influence the number of Chinese workers. Worker numbers appear to decrease significantly only in the aftermath of large-scale violent events. These findings suggest that Chinese companies are relatively acceptant of security risks and uncertainties, despite the decade-long regulatory efforts of the Chinese government to make them more security-conscious overseas and, thus, to reduce pressure to use diplomatically and economically expensive military means for their protection.

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Complicated cutaneous leishmaniasis caused by an imported case of Leishmania tropica in Japan: a case report

Tropical Medicine and Health ◽

10.1186/s41182-021-00312-4 ◽

2021 ◽

Vol 49 (1) ◽

Author(s):

Hiroyuki Kitano ◽

Chizu Sanjoba ◽

Yasuyuki Goto ◽

Kazumasa Iwamoto ◽

Hiroki Kitagawa ◽

...

Keyword(s):

Cutaneous Leishmaniasis ◽

Skin Lesions ◽

Leishmania Tropica ◽

Case Presentation ◽

Imported Case ◽

Imported Cases ◽

History Of ◽

Hematoxylin And Eosin ◽

Polymerase Chain ◽

Positive Results

Abstract Background Leishmaniasis is not endemic in Japan, and imported cases are rare. However, there are increasing concerns regarding imported cases of cutaneous leishmaniasis from endemic countries to Japan. This report describes a case of imported cutaneous leishmaniasis that was diagnosed and treated in Japan. Case presentation A 53-year-old Pakistani man presented with skin lesions on both malleoli of his right ankle and the dorsum of the left foot. The skin lesions manifested as erythematous nodules surrounding an ulcer in the center of the lesion. The lesions of the malleoli of his right ankle each measured 3 × 3 cm, and the lesion on the top of his left foot measured 5 × 4 cm. He had been living and working in Japan but had a history of a visit to Pakistan for about 2 months in 2018. The skin lesions were biopsied. Giemsa and hematoxylin and eosin staining of biopsy samples showed amastigotes of Leishmania in macrophages, and the presence of Leishmania was confirmed by skin tissue culture. Polymerase chain reaction using biopsy specimens identified Leishmania parasites, and DNA sequence analysis revealed that the species was Leishmania tropica. The patient was treated with intravenous liposomal amphotericin B for 6 days. The erythema disappeared, and the erythematous nodules resolved within 3 weeks. Conclusion This is the first report of imported cutaneous leishmaniasis caused by L. tropica from Pakistan, and it is interesting that all three testing modalities showed positive results in this case.

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The Role of CD1a expression in the diagnosis of cutaneous leishmaniasis, its relationship with Leishmania species and clinicopathological features

Dermatologic Therapy ◽

10.1111/dth.14977 ◽

2021 ◽

Author(s):

Yasemin Yuyucu Karabulut ◽

Funda KuŞ Bozkurt ◽

Ümit Türsen ◽

Gül Bayram ◽

Gülhan Örekeci Temel ◽

...

Keyword(s):

Cutaneous Leishmaniasis ◽

Leishmania Species ◽

Clinicopathological Features

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Film-Forming Systems for the Delivery of DNDI-0690 to Treat Cutaneous Leishmaniasis

Pharmaceutics ◽

10.3390/pharmaceutics13040516 ◽

2021 ◽

Vol 13 (4) ◽

pp. 516

Author(s):

Katrien Van Bocxlaer ◽

Kerri-Nicola McArthur ◽

Andy Harris ◽

Mo Alavijeh ◽

Stéphanie Braillard ◽

...

Keyword(s):

Drug Delivery ◽

Cutaneous Leishmaniasis ◽

Mouse Skin ◽

Parasite Load ◽

Leishmania Species ◽

Lesion Size ◽

Drying Time ◽

Sustained Drug Delivery ◽

Film Forming ◽

The Impact

In cutaneous leishmaniasis (CL), parasites reside in the dermis, creating an opportunity for local drug administration potentially reducing adverse effects and improving treatment adherence compared to current therapies. Polymeric film-forming systems (FFSs) are directly applied to the skin and form a thin film as the solvent evaporates. In contrast to conventional topical dosage forms, FFSs strongly adhere to the skin, favouring sustained drug delivery to the affected site, reducing the need for frequent applications, and enhancing patient compliance. This study reports the first investigation of the use of film-forming systems for the delivery of DNDI-0690, a nitroimidazole compound with potent activity against CL-causing Leishmania species. A total of seven polymers with or without plasticiser were evaluated for drying time, stickiness, film-flexibility, and cosmetic attributes; three FFSs yielded a positive evaluation for all test parameters. The impact of each of these FFSs on the permeation of the model skin permeant hydrocortisone (hydrocortisone, 1% (w/v) across the Strat-M membrane was evaluated, and the formulations resulting in the highest and lowest permeation flux (Klucel LF with triethyl citrate and Eudragit RS with dibutyl sebacate, respectively) were selected as the FFS vehicle for DNDI-0690. The release and skin distribution of the drug upon application to Leishmania-infected and uninfected BALB/c mouse skin were examined using Franz diffusion cells followed by an evaluation of the efficacy of both DNDI-0690 FFSs (1% (w/v)) in an experimental CL model. Whereas the Eudragit film resulted in a higher permeation of DNDI-0690, the Klucel film was able to deposit four times more drug into the skin, where the parasite resides. Of the FFSs formulations, only the Eudragit system resulted in a reduced parasite load, but not reduced lesion size, when compared to the vehicle only control. Whereas drug delivery into the skin was successfully modulated using different FFS systems, the FFS systems selected were not effective for the topical application of DNDI-0690. The convenience and aesthetic of FFS systems alongside their ability to modulate drug delivery to and into the skin merit further investigation using other promising antileishmanial drugs.

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