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1.
BMC Infect Dis ; 24(1): 332, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509490

RESUMO

OBJECTIVE: Cutaneous Leishmaniasis (CL) is one of the highly prevalent endemic diseases in the Middle East. The disease is a complex skin infection imposing a heavy burden on many developing countries. This study aimed to evaluate the impact of adding oral fluconazole to topical cryotherapy on the treatment efficacy and time to achieve complete recovery of CL lesions. METHOD: This triple-blind randomized clinical trial included 52 participants with CL. Participants were allocated to receive either weekly cryotherapy with liquid nitrogen and oral fluconazole at a dose of 6 mg/kg daily at a maximum of 400 mg for 6 weeks as the interventional arm or weekly cryotherapy with liquid nitrogen plus the placebo for the same period of 6 weeks as the control arm. RESULTS: Fifty-two eligible participants enrolled the study, with a CL lesion count of 1 to 8 (mean 1.96), and served as the interventional (n = 28) and control (n = 24) arms. The trend of the mean surface area of the lesions was significantly decreasing in both arms (P < 0.001), with no statistically significant difference between arms (P = 0.133) or all assessed time point pairwise comparisons (P > 0.05). There was no significant difference between the treatment arms in terms of the end-point recovery status (P = 0.491) or the frequency of post-treatment secretion (P = 0.437). No adverse effect was observed. CONCLUSION: Despite a slightly higher reduction in the lesion surface in the cryotherapy and fluconazole treatment arm, the addition of fluconazole did not provide statistically significant therapeutic value to cryotherapy in the treatment of CL. However, with adjustment for the initial lesion size, the efficacy of the regimen in the interventional arm was more pronounced, though it was still insignificant.


Assuntos
Fluconazol , Leishmaniose Cutânea , Humanos , Fluconazol/uso terapêutico , Leishmaniose Cutânea/tratamento farmacológico , Oriente Médio , Resultado do Tratamento , Crioterapia , Nitrogênio
3.
PLoS Negl Trop Dis ; 18(3): e0012006, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38437246

RESUMO

BACKGROUND: Imported cutaneous leishmaniasis (CL) is a growing problem with increasing global travel to endemic areas. Returned travelers with CL are easy to be misdiagnosed and mistreated due to the lack of awareness for the disease to the physicians in non-endemic region that may lead to unfavorable outcome. Our study intends to summarize the characteristics of Leishmania infection imported from Iraq, so as to help Chinese physicians diagnose and treat the disease. All CL patients were treated with intralesional injection of antimony. METHODS: The definitive diagnosis of CL is based on the parasite identification by microscopic examination directly on lesion smear or parasite culture, PCR amplification of Leishmania-specific internal transcribed spacer 1 (ITS-1). The phylogenetic analysis, the immunopathological examination and the cytokine detection were proceeded after the diagnosis. RESULTS: We have identified 25 CL cases in migrant Chinese workers returned from Iraq for the first time with L. major as the major species of infected Leishmania parasite. Clinical features of the Iraq-imported CL include the history of skin exposure to sandflies bite and the lesions mostly on the exposed limbs. More ulcerative wet lesion was observed than nodular dry lesion. PCR is not only used to detect Leishmania parasite with high sensitivity, but also to identify the species of infected parasite through sequencing the amplified Leishmania-specific ITS-1 gene. The phylogenetic analysis based on the amplified ITS-1 sequences revealed that the infected Leishmania was closed related to the species and strains endemic in Iraq. The immunopathological examination revealed the T-cell filtrated cellular immune response with less B cells and NK cells involved. The cytokine profile measured in the skin lesion also confirmed the Th1 cellular response with higher expression levels of IFN-γ, IL-6 and IL-8. The skin lesions in CL patients were healed after being treated locally with antimony. CONCLUSIONS: The clinical and parasitological features of these Chinese CL cases imported from Iraq provide useful information for the diagnosis and treatment of CL that is not commonly seen in Chinese local population.


Assuntos
Leishmania , Leishmaniose Cutânea , Migrantes , Humanos , Filogenia , Antimônio , Iraque , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/epidemiologia , Leishmania/genética , Citocinas/genética , China/epidemiologia
4.
Med Microbiol Immunol ; 213(1): 4, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38532203

RESUMO

Besides being scarce, the drugs available for treating cutaneous leishmaniasis have many adverse effects. Ozone is an option to enhance the standard treatment due to the wound-healing activity reported in the literature. In this study, we evaluated the efficiency of ozonated sunflower oil as an adjuvant in treating cutaneous lesions caused by Leishmania amazonensis. BALB/c mice were infected with L. amazonensis, and after the lesions appeared, they were treated in four different schedules using the drug treatment with meglumine antimoniate (Glucantime®), with or without ozonated oil. After thirty days of treatment, the lesions' thickness and their parasitic burden, blood leukocytes, production of NO and cytokines from peritoneal macrophages and lymph node cells were analyzed. The group treated with ozonated oil plus meglumine antimoniate showed the best performance, improving the lesion significantly. The parasitic burden showed that ozonated oil enhanced the leishmanicidal activity of the treatment, eliminating the parasites in the lesion. Besides, a decrease in the TNF levels from peritoneal macrophages and blood leukocytes demonstrated an immunomodulatory action of ozone in the ozonated oil-treated animals compared to the untreated group. Thus, ozonated sunflower oil therapy has been shown as an adjuvant in treating Leishmania lesions since this treatment enhanced the leishmanicidal and wound healing effects of meglumine antimoniate.


Assuntos
Antiprotozoários , Leishmaniose Cutânea , Ozônio , Animais , Camundongos , Antimoniato de Meglumina/farmacologia , Antimoniato de Meglumina/uso terapêutico , Óleo de Girassol/uso terapêutico , Antiprotozoários/farmacologia , Meglumina/farmacologia , Meglumina/uso terapêutico , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/parasitologia , Cicatrização , Ozônio/uso terapêutico , Camundongos Endogâmicos BALB C
5.
Acta Microbiol Immunol Hung ; 71(1): 89-98, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38520480

RESUMO

Cutaneous Leishmaniasis (CL) is one of the world's neglected diseases which is caused by Leishmania spp. The aim of this study was to assess molecular profile and antimony resistance of Leishmania isolated from human and rodent hosts. Samples were collected from suspected CL patients referred to health centres and wild rodent's traps in Gonbad-e-Qabus region, north-eastern Iran. Smears were subjected to PCR-RFLP to identify Leishmania species. In addition, ITS1-PCR products were sequenced for phylogenetic analysis. Clinical isolates and rodent samples were subjected to MTT assay to determine IC50 values and in vitro susceptibilities. Expression levels of antimony resistance-related genes were determined in CL isolates. Out of 1,949 suspected patients with CL and 148 rodents, 1,704 (87.4%) and 6 (4.05%) were positive with direct smear, respectively. Digestion patterns of BusRI (HaeIII) endonuclease enzyme were similar to what expected for Leishmania major. Phylogenetic analysis revealed that the highest interspecies similarity was found between current L. major sequences with L. major obtained from Russia and Uzbekistan. Out of 20 L. major samples tested, 13 (65%) were resistant to meglumine antimoniate (MA) treatment, with an activity index (AI) exceeding 4. The remaining 7 samples (35%) responded to MA treatment and were classified as sensitive isolates, with a confirmed sensitive phenotype based on their AI values. The comparison expression analysis of three major antimony resistance-associated genes in unresponsive clinical isolates demonstrated significant fold changes for TDR1 (4.78-fold), AQP1 (1.3-fold), and γ-GCS (1.17-fold) genes (P < 0.05). Herein, we demonstrate genetic diversity and antimony resistance of L. major isolated from human and reservoir hosts in north-eastern Iran, which could be the basis for planning future control strategies.


Assuntos
Leishmania major , Leishmaniose Cutânea , Animais , Humanos , Leishmania major/genética , Filogenia , Antimônio/farmacologia , Antimônio/uso terapêutico , Roedores , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/tratamento farmacológico , Antimoniato de Meglumina/uso terapêutico
6.
IUCrJ ; 11(Pt 2): 224-236, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38427455

RESUMO

Leishmaniasis is a neglected parasitic tropical disease with numerous clinical manifestations. One of the causative agents of cutaneous leishmaniasis (CL) is Leishmania tropica (L. tropica) known for causing ulcerative lesions on the skin. The adverse effects of the recommended available drugs, such as amphotericin B and pentavalent antimonial, and the emergence of drug resistance in parasites, mean the search for new safe and effective anti-leishmanial agents is crucial. Miltefosine (MIL) was the first recommended oral medication, but its use is now limited because of the rapid emergence of resistance. Pharmaceutical cocrystallization is an effective method to improve the physicochemical and biological properties of active pharmaceutical ingredients (APIs). Herein, we describe the cocrystallization of coumarin-3-carboxylic acid (CU, 1a; 2-oxobenzopyrane-3-carboxylic acid, C10H6O4) with five coformers [2-amino-3-bromopyridine (1b), 2-amino-5-(trifluoromethyl)-pyridine (1c), 2-amino-6-methylpyridine (1d), p-aminobenzoic acid (1e) and amitrole (1f)] in a 1:1 stoichiometric ratio via the neat grinding method. The cocrystals 2-6 obtained were characterized via single-crystal X-ray diffraction, powder X-ray diffraction, differential scanning calorimetry and thermogravimetric analysis, as well as Fourier transform infrared spectroscopy. Non-covalent interactions, such as van der Waals, hydrogen bonding, C-H...π and π...π interactions contribute significantly towards the packing of a crystal structure and alter the physicochemical and biological activity of CU. In this research, newly synthesized cocrystals were evaluated for their anti-leishmanial activity against the MIL-resistant L. tropica and cytotoxicity against the 3T3 (normal fibroblast) cell line. Among the non-cytotoxic cocrystals synthesized (2-6), CU:1b (2, IC50 = 61.83 ± 0.59 µM), CU:1c (3, 125.7 ± 1.15 µM) and CU:1d (4, 48.71 ± 0.75 µM) appeared to be potent anti-leishmanial agents and showed several-fold more anti-leishmanial potential than the tested standard drug (MIL, IC50 = 169.55 ± 0.078 µM). The results indicate that cocrystals 2-4 are promising anti-leishmanial agents which require further exploration.


Assuntos
Antiprotozoários , Leishmania tropica , Leishmaniose Cutânea , Humanos , Antiprotozoários/farmacologia , Leishmaniose Cutânea/tratamento farmacológico , Cristalografia por Raios X , Cumarínicos/farmacologia
7.
J Ethnopharmacol ; 328: 118028, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38492792

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Species of Vismia (Hypericaceae), known in Brazil as "lacre", are commonly used in traditional Amazonian medicine for the treatment of skin lesions, including those caused by Leishmania infection. AIM OF THE STUDY: Hexane extracts from the leaves of Vismia cayennensis, V. gracilis, V. sandwithii and V. guianensis, as well as from the fruits of the latter, in addition to the anthraquinones vismiaquinone, physcion and chrysophanol isolated from these species were explored for their anti-promastigote and anti-amastigote activity on Leishmania amazonensis. MATERIALS AND METHODS: Extracts were prepared by static maceration with n-hexane. The compounds, isolated by chromatographic techniques, were identified by spectroscopic methods (1H and 13C NMR). Promastigotes of L.amazonensis were incubated with hexane extracts (1-50 µg/mL) or anthraquinones (1-50 µM) and the parasite survival analyzed. The action of compounds on reactive oxygen species (ROS) production, mitochondrial membrane potential, and membrane integrity of promastigotes were evaluated by flow cytometer, and the cytotoxicity on mammalian cells using MTT assay. Furthermore, the activity of compounds against amastigotes and nitric oxide production were also investigated. RESULTS: Vismiaquinone and physcion were obtained from the leaves of V. guianensis. Physcion, as well as chrysophanol, were isolated from V. sandwithii. Vismia cayennensis and V. gracilis also showed vismiaquinone, compound detected in lower quantity in the fruits of V. guianensis. All extracts were active against the parasite, corroborating the popular use. The greatest activity against promastigotes was achieved with V. guianensis extract (IC50 4.3 µg/mL), precisely the most used Vismia species for treating cutaneous leishmaniasis. Vismiaquinone and physcion exhibited relevant activity with IC50 12.6 and 2.6 µM, respectively. Moreover, all extracts and anthraquinones tested induced ROS production, mitochondrial dysfunction, membrane disruption and were able to kill intracellular amastigote forms, being worthy of further in vivo studies as potential antileishmanial drugs. CONCLUSIONS: The overall data achieved in the current investigation scientifically validate the traditional use of Vismia species, mainly V. guianensis, as an anti-Leishmania agent. Furthermore, the promising results presented here indicate species of Vismia as potentially useful resources of Brazilian flora for the discovery of therapeutic solutions for neglected diseases.


Assuntos
Antiprotozoários , Clusiaceae , Emodina/análogos & derivados , Leishmaniose Cutânea , Leishmaniose , Plantas Medicinais , Animais , Camundongos , Hexanos , Espécies Reativas de Oxigênio , Antraquinonas/farmacologia , Antraquinonas/uso terapêutico , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose/tratamento farmacológico , Camundongos Endogâmicos BALB C , Mamíferos
8.
Org Biomol Chem ; 22(9): 1812-1820, 2024 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-38328995

RESUMO

A library of hybrid molecules is developed based on the common chemical features shared by clemastine and tamoxifen both of which are well known for their antileishmanial activities. In the initial screening against Leishmania major and L. amazonensis promastigotes, as well as cytotoxicity assays using HepG2 cells, several hybrids showed submicromolar activity against the parasite and no toxicity against human cells. The compounds with an EC50 < 2 µM against promastigotes of both species and a selectivity index >10 were further characterized against intracellular amastigotes as well as promastigotes of species that cause both visceral and cutaneous leishmaniasis, such as L. infantum and L. braziliensis, respectively. These sequential screenings revealed the high pan-activity of this class of molecules against these species, with several compounds displaying an EC50 ≤ 2 µM against both promastigotes and intracellular amastigotes. Two of them were identified as the potential templates for lead optimization of this series having shown the highest activities against all species in both stages of parasite. The present findings can serve as a good starting point in the search for novel antileishmanial compounds that are easy to access and highly active.


Assuntos
Antiprotozoários , Leishmaniose Cutânea , Humanos , Animais , Camundongos , Clemastina/uso terapêutico , Macrófagos , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/parasitologia , Antiprotozoários/farmacologia , Células Hep G2 , Camundongos Endogâmicos BALB C
9.
PLoS One ; 19(2): e0296728, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38354178

RESUMO

INTRODUCTION: American Tegumentary Leishmaniasis (ATL) treatment is based on pentavalent antimonials (Sb5+), but these drugs have been associated to several adverse effects. Hearing loss and tinnitus during treatment with meglumine antimoniate (MA) have already been reported. This study aimed to describe the usefulness of self-reporting of hearing loss and tinnitus in diagnosing MA-induced ototoxicity. METHODS: A prospective longitudinal study was conducted with 102 patients with parasitological diagnosis of ATL, treated with different MA schemes. The presence of clinical auditory toxicity was defined as the emergence or worsening of self-reporting hearing loss and/or tinnitus during monitoring. Measures of sensitivity, specificity, and the positive and negative predictive value of the patient's self-reporting of hearing loss and tinnitus in relation to the result of the audiometric test (considered the gold standard) were calculated. RESULTS: The age of the evaluated patients ranged from 15 to 81 years, with a median of 41 years, and most were male (73.5%). Seventy-five patients (73.5%) had cutaneous leishmaniasis and 27 (26.5%) mucosal leishmaniasis. Eighty-six patients (84.3%) received intramuscular (IM) treatment and 16 (15.7%) were treated with intralesional MA. During treatment, 18 (17,6%) had tinnitus and 7 (6,9%) had complaint of hearing loss. 53 (52%) patients had cochlear toxicity confirmed by tone threshold audiometry and high frequency audiometry, from which 60% received a dose of 20 mg Sb5+/kg/day (p = 0.015) and 96.2% were treated with IM MA (p = 0.001). Tinnitus has greater specificity and positive predictive value than hearing loss, with a low number of false positives, but with a high false negative value. CONCLUSION: Although the large number of false negatives suggests that self-report of hearing loss or tinnitus cannot be considered a good screening test for referring the patient to an audiometry, the low number of false positives suggests the need to value the patient's complaint for referral. Otherwise, this study reinforces the importance of audiological monitoring during treatment with MA, especially in those patients with self-reporting of hearing loss or tinnitus when treated with 20 mg Sb5+/kg/day via IM.


Assuntos
Antiprotozoários , Surdez , Perda Auditiva , Leishmaniose Cutânea , Compostos Organometálicos , Ototoxicidade , Zumbido , Humanos , Masculino , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Feminino , Antimoniato de Meglumina/efeitos adversos , Zumbido/induzido quimicamente , Zumbido/diagnóstico , Zumbido/tratamento farmacológico , Meglumina/efeitos adversos , Antiprotozoários/uso terapêutico , Estudos Longitudinais , Estudos Prospectivos , Compostos Organometálicos/efeitos adversos , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/tratamento farmacológico , Perda Auditiva/induzido quimicamente , Perda Auditiva/diagnóstico
10.
J Trace Elem Med Biol ; 83: 127404, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38364464

RESUMO

BACKGROUND: Cutaneous leishmaniasis (LC) is an infectious vector-borne disease caused by parasites belonging to the genus Leishmania. Metallic nanoparticles (MNPs) have been investigated as alternatives for the treatment of LC owing to their small size and high surface area. Here, we aimed to evaluate the effect of MNPs in the treatment of LC through experimental, in vitro and in vivo investigations. METHODS: The databases used were MEDLINE/ PubMed, Scopus, Web of Science, Embase, and Science Direct. Manual searches of the reference lists of the included studies and grey literature were also performed. English language and experimental in vitro and in vivo studies using different Leishmania species, both related to MNP treatment, were included. This study was registered in PROSPERO (CRD42021248245). RESULTS: A total of 93 articles were included. Silver nanoparticles are the most studied MNPs, and L. tropica is the most studied species. Among the mechanisms of action of MNPs in vitro, we highlight the production of reactive oxygen species, direct contact of MNPs with the biomolecules of the parasite, and release of metal ions. CONCLUSION: MNPs may be considered a promising alternative for the treatment of LC, but further studies are needed to define their efficacy and safety.


Assuntos
Leishmania tropica , Leishmaniose Cutânea , Nanopartículas Metálicas , Humanos , Nanopartículas Metálicas/uso terapêutico , Prata/uso terapêutico , Prata/farmacologia , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/parasitologia
11.
PLoS Negl Trop Dis ; 18(2): e0011975, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38381805

RESUMO

BACKGROUND: Target Product Profiles (TPPs) are instrumental to help optimise the design and development of therapeutics, vaccines, and diagnostics - these products, in order to achieve the intended impact, should be aligned with users' preferences and needs. However, patients are rarely involved as key stakeholders in building a TPP. METHODOLOGY: Thirty-three cutaneous leishmaniasis (CL) patients from Brazil, Colombia, and Austria, infected with New-World Leishmania species, were recruited using a maximum variation approach along geographic, sociodemographic and clinical criteria. Semi-structured interviews were conducted in the respective patient's mother tongue. Transcripts, translated into English, were analysed using a framework approach. We matched disease experiences, preferences, and expectations of CL patients to a TPP developed by DNDi (Drug for Neglected Diseases initiative) for CL treatment. PRINCIPAL FINDINGS: Patients' preferences regarding treatments ranged from specific efficacy and safety endpoints to direct and significant indirect costs. Respondents expressed views about trade-offs between efficacy and experienced discomfort/adverse events caused by treatment. Reasons for non-compliance, such as adverse events or geographical and availability barriers, were discussed. Considerations related to accessibility and affordability were relevant from the patients' perspective. CONCLUSIONS/SIGNIFICANCE: NTDs affect disadvantaged populations, often with little access to health systems. Engaging patients in designing adapted therapies could significantly contribute to the suitability of an intervention to a specific context and to compliance, by tailoring the product to the end-users' needs. This exploratory study identified preferences in a broad international patient spectrum. It provides methodological guidance on how patients can be meaningfully involved as stakeholders in the construction of a TPP of therapeutics for NTDs. CL is used as an exemplar, but the approach can be adapted for other NTDs.


Assuntos
Leishmaniose Cutânea , Doenças Negligenciadas , Humanos , Doenças Negligenciadas/prevenção & controle , Leishmaniose Cutânea/tratamento farmacológico , Desenvolvimento de Medicamentos , Pesquisa Qualitativa , Custos e Análise de Custo
12.
Emerg Infect Dis ; 30(3): 510-518, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38407142

RESUMO

Disseminated leishmaniasis (DL) is an emergent severe disease manifesting with multiple lesions. To determine the relationship between immune response and clinical and therapeutic outcomes, we studied 101 DL and 101 cutaneous leishmaniasis (CL) cases and determined cytokines and chemokines in supernatants of mononuclear cells stimulated with leishmania antigen. Patients were treated with meglumine antimoniate (20 mg/kg) for 20 days (CL) or 30 days (DL); 19 DL patients were instead treated with amphotericin B, miltefosine, or miltefosine and meglumine antimoniate. High levels of chemokine ligand 9 were associated with more severe DL. The cure rate for meglumine antimoniate was low for both DL (44%) and CL (60%), but healing time was longer in DL (p = 0.003). The lowest cure rate (22%) was found in DL patients with >100 lesions. However, meglumine antimoniate/miltefosine treatment cured all DL patients who received it; therefore, that combination should be considered as first choice therapy.


Assuntos
Leishmania braziliensis , Leishmania , Leishmaniose Cutânea , Fosforilcolina/análogos & derivados , Humanos , Antimoniato de Meglumina/uso terapêutico , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/tratamento farmacológico
13.
Int J Parasitol Drugs Drug Resist ; 24: 100525, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38359731

RESUMO

Leishmaniasis is a disease caused by Leishmania spp., affecting millions of people around the world. For decades, its treatment has been based on pentavalent antimonials, which notoriously cause toxic side effects in patients. In this study, epoxy-α-lapachone incorporated into an oil-in-water-type microemulsion (ELAP-ME) and meglumine antimoniate (MA) were assayed in monotherapy and in combination (ELAP-ME/MA) in BALB/c mice infected with Leishmania (Leishmania) amazonensis. In general, there was a reduction in paw lesion size (up to 37% reduction) and decreases of parasite loads in the footpad (∼40%) and lymph nodes (∼31%) of animals treated with ELAP-ME/MA, when compared to the non-treated control groups. Analyses of serum biochemical parameters revealed that the ELAP-ME/MA showed lower renal and hepatic toxicity when compared to MA 2-doses/week monotherapy. These findings indicate that the ELAP-ME/MA combination may be a promising approach for the treatment of cutaneous leishmaniasis.


Assuntos
Antiprotozoários , Leishmania , Leishmaniose Cutânea , Naftoquinonas , Compostos Organometálicos , Humanos , Animais , Camundongos , Antimoniato de Meglumina/uso terapêutico , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/parasitologia , Meglumina/uso terapêutico , Compostos Organometálicos/uso terapêutico , Camundongos Endogâmicos BALB C
14.
Carbohydr Res ; 536: 109015, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38198982

RESUMO

The protozoan parasite Leishmania (Viannia) braziliensis is among Latin America's most widespread Leishmania species and is responsible for tegumentary leishmaniasis (TL). This disease has multiple clinical presentations, with cutaneous leishmaniasis (CL) being the most frequent. It manifests as one or a few localized skin ulcers, which can spread to other body areas. Hence, early diagnosis and treatment, typically with pentavalent antimonials, is critical. Traditional diagnostic methods, like parasite culture, microscopy, or the polymerase chain reaction (PCR) for detection of the parasite DNA, have limitations due to the uneven distribution of parasites in biopsy samples. Nonetheless, studies have revealed high levels of parasite-specific anti-α-Gal antibodies in L. (V.) braziliensis-infected patients. Previously, we demonstrated that the neoglycoprotein NGP28b, consisting of the L. (Leishmania) major type-2 glycoinositolphospholipid (GIPL)-3-derived trisaccharide Galpα1,6Galpα1,3Galfß conjugated to bovine serum albumin (BSA) via a linker, acts as a reliable serological biomarker (BMK) for L. (V.) braziliensis infection in Brazil. This indicates the presence of GIPL-3 or a similar structure in this parasite, and its terminal trisaccharide either functions as or is part of an immunodominant glycotope. Here, we explored whether extending the trisaccharide with a mannose unit would enhance its efficacy as a biomarker for the serological detection of L. (V.) braziliensis. We synthesized the tetrasaccharide Galpα1,6Galpα1,3Galfß1,3Manpα(CH2)3SH (G31SH) and conjugated it to maleimide-functionalized BSA to afford NGP31b. When we assessed the efficacy of NGP28b and NGP31b by chemiluminescent enzyme-linked immunosorbent assay on a cohort of CL patients with L. (V.) braziliensis infection from Bolivia and Argentina against a healthy control group, both NGPs exhibited similar or identical sensitivity, specificity, and accuracy. This finding implies that the mannose moiety at the reducing end is not part of the glycotope recognized by the parasite-specific anti-α-Gal antibodies in patients' sera, nor does it exert a relevant influence on the terminal trisaccharide's conformation. Moreover, the mannose does not seem to inhibit glycan-antibody interactions. Therefore, NGP31b is a viable and dependable BMK for the serodiagnosis of CL caused by L. (V.) braziliensis.


Assuntos
Leishmania braziliensis , Leishmaniose Cutânea , Humanos , Leishmania braziliensis/genética , Manose , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/tratamento farmacológico , Glicoproteínas , Trissacarídeos
16.
Int J Mol Sci ; 25(1)2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38203832

RESUMO

Chemotherapy currently available for leishmaniasis treatment has many adverse side effects and drug resistance. Therefore, the identification of new targets and the development of new drugs are urgently needed. Previously, we reported the synthesis of a N-(2-methoxyphenyl)-1-methyl-1H-benzimidazol-2-amine, named compound 8, with an IC50 value in the micromolar range against L. mexicana, it also inhibited 68.27% the activity of recombinant L. mexicana arginase. Herein, we report studies carried out to characterize the mechanism of action of compound 8, as well as its in vivo leishmanicidal activity. It was shown in our ultrastructural studies that compound 8 induces several changes, such as membrane blebbing, the presence of autophagosomes, membrane detachment and mitochondrial and kinetoplast disorganization, among others. Compound 8 triggers the production of ROS and parasite apoptosis. It reduced 71% of the parasite load of L. mexicana in an experimental model of cutaneous leishmaniasis in comparison with a control. Altogether, the data obtained suggest the potential use of compound 8 in the treatment of cutaneous leishmaniasis.


Assuntos
Leishmania mexicana , Leishmaniose Cutânea , Humanos , Leishmaniose Cutânea/tratamento farmacológico , Apoptose , Arginase , Benzimidazóis/farmacologia , Aminas
17.
J Immunol ; 212(5): 894-903, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38231122

RESUMO

The immune response is central to the pathogenesis of cutaneous leishmaniasis (CL). However, most of our current understanding of the immune response in human CL derives from the analysis of systemic responses, which only partially reflect what occurs in the skin. In this study, we characterized the transcriptional dynamics of skin lesions during the course of treatment of CL patients and identified gene signatures and pathways associated with healing and nonhealing responses. We performed a comparative transcriptome profiling of serial skin lesion biopsies obtained before, in the middle, and at the end of treatment of CL patients (eight who were cured and eight with treatment failure). Lesion transcriptomes from patients who healed revealed recovery of the stratum corneum, suppression of the T cell-mediated inflammatory response, and damping of neutrophil activation, as early as 10 d after initiation of treatment. These transcriptional programs of healing were consolidated before lesion re-epithelization. In stark contrast, downregulation of genes involved in keratinization was observed throughout treatment in patients who did not heal, indicating that in addition to uncontrolled inflammation, treatment failure of CL is mediated by impaired mechanisms of wound healing. This work provides insights into the factors that contribute to the effective resolution of skin lesions caused by Leishmania (Viannia) species, sheds light on the consolidation of transcriptional programs of healing and nonhealing responses before the clinically apparent resolution of skin lesions, and identifies inflammatory and wound healing targets for host-directed therapies for CL.


Assuntos
Leishmania braziliensis , Leishmania , Leishmaniose Cutânea , Humanos , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/genética , Pele/patologia , Cicatrização/genética , Leishmania braziliensis/fisiologia
18.
Arch Med Res ; 55(2): 102958, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38290200

RESUMO

BACKGROUND: Chagas disease and cutaneous leishmaniasis, two parasitic diseases caused by Trypanosoma cruzi (T. cruzi) and Leishmania mexicana (L. mexicana), respectively, have a major global impact. Current pharmacological treatments for these diseases are limited and can cause severe side effects; thus, there is a need for new antiprotozoal drugs. METHODS: Using molecular docking, this work describes a structure-based virtual screening of an FDA-approved drug library against Trypanosoma cruzi and Leishmania mexicana glycolytic enzyme triosephosphate isomerase (TIM), which is highly conserved in these parasites. The selected compounds with potential dual inhibitory activity were tested in vitro to confirm their biological activity. RESULTS: The study showed that five compounds: nilotinib, chlorhexidine, protriptyline, cyproheptadine, and montelukast, were more active against T. cruzi, than the reference drugs, nifurtimox and benznidazole while chlorhexidine and protriptyline were the most active against L. mexicana. CONCLUSIONS: The analysis of these compounds and their structural characteristics may provide the basis for the development of new antiprotozoal agents.


Assuntos
Antiprotozoários , Doença de Chagas , Leishmaniose Cutânea , Trypanosoma cruzi , Humanos , Simulação de Acoplamento Molecular , Clorexidina/farmacologia , Clorexidina/uso terapêutico , Protriptilina/farmacologia , Protriptilina/uso terapêutico , Doença de Chagas/tratamento farmacológico , Leishmaniose Cutânea/tratamento farmacológico , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Antiprotozoários/química
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