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1.
An Acad Bras Cienc ; 96(2): e20230375, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38747836

RESUMO

In pursuit of potential agents to treat Chagas disease and leishmaniasis, we report the design, synthesis, and identification novel naphthoquinone hydrazide-based molecular hybrids. The compounds were subjected to in vitro trypanocide and leishmanicidal activities. N'-(1,4-Dioxo-1,4-dihydronaphthalen-2-yl)-3,5-dimethoxybenzohydrazide (13) showed the best performance against Trypanosoma cruzi (IC50 1.83 µM) and Leishmania amazonensis (IC50 9.65 µM). 4-Bromo-N'-(1,4-dioxo-1,4-dihydronaphthalen-2-yl)benzohydrazide (16) exhibited leishmanicidal activity (IC50 12.16 µM). Regarding trypanocide activity, compound 13 was low cytotoxic to LLC-MK2 cells (SI = 95.28). Furthermore, through molecular modeling studies, the cysteine proteases cruzain, rhodesain and CPB2.8 were identified as the potential biological targets.


Assuntos
Desenho de Fármacos , Hidrazinas , Leishmania , Naftoquinonas , Tripanossomicidas , Trypanosoma cruzi , Naftoquinonas/farmacologia , Naftoquinonas/química , Naftoquinonas/síntese química , Trypanosoma cruzi/efeitos dos fármacos , Tripanossomicidas/farmacologia , Tripanossomicidas/síntese química , Tripanossomicidas/química , Leishmania/efeitos dos fármacos , Hidrazinas/química , Hidrazinas/farmacologia , Animais , Antiprotozoários/farmacologia , Antiprotozoários/síntese química , Antiprotozoários/química , Testes de Sensibilidade Parasitária , Concentração Inibidora 50 , Relação Estrutura-Atividade , Cisteína Endopeptidases
2.
Amino Acids ; 56(1): 35, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698213

RESUMO

Chagas disease, caused by the protozoa Trypanosoma cruzi, continues to be a serious public health problem in Latin America, worsened by the limitations in its detection. Given the importance of developing new diagnostic methods for this disease, the present review aimed to verify the number of publications dedicated to research on peptides that demonstrate their usefulness in serodiagnosis. To this end, a bibliographic survey was conducted on the PubMed platform using the keyword "peptide" or "epitope" combined with "Chagas disease" or "Trypanosoma cruzi"; "diagno*" or "serodiagnosis" or "immunodiagnosis", without period restriction. An increasing number of publications on studies employing peptides in ELISA and rapid tests assays was verified, which confirms the expansion of research in this field. It is possible to observe that many of the peptides tested so far originate from proteins widely used in the diagnosis of Chagas, and many of them are part of commercial tests developed. In this sense, as expected, promising results were obtained for several peptides when tested in ELISA, as many of them exhibited sensitivity and specificity values above 90%. Furthermore, some peptides have been tested in several studies, confirming their diagnostic potential. Despite the promising results observed, it is possible to emphasize the need for extensive testing of peptides, using different serological panels, in order to confirm their potential. The importance of producing an effective assay capable of detecting the clinical stages of the disease, as well as new immunogenic antigens that enable new serological diagnostic tools for Chagas disease, is evident.


Assuntos
Doença de Chagas , Ensaio de Imunoadsorção Enzimática , Peptídeos , Trypanosoma cruzi , Doença de Chagas/diagnóstico , Doença de Chagas/imunologia , Doença de Chagas/sangue , Humanos , Trypanosoma cruzi/imunologia , Peptídeos/imunologia , Peptídeos/química , Ensaio de Imunoadsorção Enzimática/métodos , Testes Imunológicos/métodos , Antígenos de Protozoários/imunologia , Antígenos de Protozoários/sangue , Testes Sorológicos/métodos
3.
Sci Rep ; 14(1): 10039, 2024 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-38693166

RESUMO

According to the World Health Organization, Chagas disease (CD) is the most prevalent poverty-promoting neglected tropical disease. Alarmingly, climate change is accelerating the geographical spreading of CD causative parasite, Trypanosoma cruzi, which additionally increases infection rates. Still, CD treatment remains challenging due to a lack of safe and efficient drugs. In this work, we analyze the viability of T. cruzi Akt-like kinase (TcAkt) as drug target against CD including primary structural and functional information about a parasitic Akt protein. Nuclear Magnetic Resonance derived information in combination with Molecular Dynamics simulations offer detailed insights into structural properties of the pleckstrin homology (PH) domain of TcAkt and its binding to phosphatidylinositol phosphate ligands (PIP). Experimental data combined with Alpha Fold proposes a model for the mechanism of action of TcAkt involving a PIP-induced disruption of the intramolecular interface between the kinase and the PH domain resulting in an open conformation enabling TcAkt kinase activity. Further docking experiments reveal that TcAkt is recognized by human inhibitors PIT-1 and capivasertib, and TcAkt inhibition by UBMC-4 and UBMC-6 is achieved via binding to TcAkt kinase domain. Our in-depth structural analysis of TcAkt reveals potential sites for drug development against CD, located at activity essential regions.


Assuntos
Doença de Chagas , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Trypanosoma cruzi , Trypanosoma cruzi/enzimologia , Trypanosoma cruzi/efeitos dos fármacos , Doença de Chagas/tratamento farmacológico , Doença de Chagas/parasitologia , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas de Protozoários/metabolismo , Proteínas de Protozoários/química , Proteínas de Protozoários/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química , Ligação Proteica
4.
PLoS Pathog ; 20(4): e1012191, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38683845

RESUMO

An imbalance between suppressor and effector immune responses may preclude cure in chronic parasitic diseases. In the case of Trypanosoma cruzi infection, specialized regulatory Foxp3+ T (Treg) cells suppress protective type-1 effector responses. Herein, we investigated the kinetics and underlying mechanisms behind the regulation of protective parasite-specific CD8+ T cell immunity during acute T. cruzi infection. Using the DEREG mouse model, we found that Treg cells play a role during the initial stages after T. cruzi infection, restraining the magnitude of CD8+ T cell responses and parasite control. Early Treg cell depletion increased the frequencies of polyfunctional short-lived, effector T cell subsets, without affecting memory precursor cell formation or the expression of activation, exhaustion and functional markers. In addition, Treg cell depletion during early infection minimally affected the antigen-presenting cell response but it boosted CD4+ T cell responses before the development of anti-parasite effector CD8+ T cell immunity. Crucially, the absence of CD39 expression on Treg cells significantly bolstered effector parasite-specific CD8+ T cell responses, preventing increased parasite replication in T. cruzi infected mice adoptively transferred with Treg cells. Our work underscores the crucial role of Treg cells in regulating protective anti-parasite immunity and provides evidence that CD39 expression by Treg cells represents a key immunomodulatory mechanism in this infection model.


Assuntos
Antígenos CD , Apirase , Linfócitos T CD8-Positivos , Doença de Chagas , Linfócitos T Reguladores , Trypanosoma cruzi , Animais , Doença de Chagas/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T CD8-Positivos/imunologia , Camundongos , Trypanosoma cruzi/imunologia , Antígenos CD/imunologia , Antígenos CD/metabolismo , Apirase/imunologia , Apirase/metabolismo , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças
5.
ACS Infect Dis ; 10(5): 1793-1807, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38648355

RESUMO

Chagas disease, caused by Trypanosoma cruzi, stands as the primary cause of dilated cardiomyopathy in the Americas. Macrophages play a crucial role in the heart's response to infection. Given their functional and phenotypic adaptability, manipulating specific macrophage subsets could be vital in aiding essential cardiovascular functions including tissue repair and defense against infection. PPARα are ligand-dependent transcription factors involved in lipid metabolism and inflammation regulation. However, the role of fenofibrate, a PPARα ligand, in the activation profile of cardiac macrophages as well as its effect on the early inflammatory and fibrotic response in the heart remains unexplored. The present study demonstrates that fenofibrate significantly reduces not only the serum activity of tissue damage biomarker enzymes (LDH and GOT) but also the circulating proportions of pro-inflammatory monocytes (CD11b+ LY6Chigh). Furthermore, both CD11b+ Ly6Clow F4/80high macrophages (MΦ) and recently differentiated CD11b+ Ly6Chigh F4/80high monocyte-derived macrophages (MdMΦ) shift toward a resolving phenotype (CD206high) in the hearts of fenofibrate-treated mice. This shift correlates with a reduction in fibrosis, inflammation, and restoration of ventricular function in the early stages of Chagas disease. These findings encourage the repositioning of fenofibrate as a potential ancillary immunotherapy adjunct to antiparasitic drugs, addressing inflammation to mitigate Chagas disease symptoms.


Assuntos
Cardiomiopatia Chagásica , Fenofibrato , Macrófagos , Fenofibrato/farmacologia , Fenofibrato/uso terapêutico , Animais , Camundongos , Cardiomiopatia Chagásica/tratamento farmacológico , Macrófagos/efeitos dos fármacos , Miocárdio/patologia , Masculino , Trypanosoma cruzi/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Miocardite/tratamento farmacológico , Miocardite/parasitologia
6.
Chem Pharm Bull (Tokyo) ; 72(4): 389-392, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38644164

RESUMO

Chagas disease, a neglected tropical disease caused by the protozoan Trypanosoma cruzi poses a significant health challenge in rural areas of Latin America. The current pharmacological options exhibit notable side effects, demand prolonged administration, and display limited efficacy. Consequently, there is an urgent need to develop drugs that are safe and clinically effective. Previously, we identified a quinone compound (designated as compound 2) with potent antiprotozoal activity, based on the chemical structure of komaroviquinone, a natural product renowned for its antitrypanosomal effects. However, compound 2 was demonstrated considerably unstable to light. In this study, we elucidated the structure of the light-induced degradation products of compound 2 and probed the correlation between the quinone ring's substituents and its susceptibility to light. Our findings led to the discovery of quinones with significantly enhanced light stability, some of which exhibiting antitrypanosomal activity. The most promising compound was evaluated for drug efficacy in a mouse model of Chagas disease, revealing where a notable reduction in blood parasitemia.


Assuntos
Doença de Chagas , Quinonas , Tripanossomicidas , Trypanosoma cruzi , Doença de Chagas/tratamento farmacológico , Animais , Trypanosoma cruzi/efeitos dos fármacos , Camundongos , Tripanossomicidas/farmacologia , Tripanossomicidas/química , Quinonas/química , Quinonas/farmacologia , Testes de Sensibilidade Parasitária , Estrutura Molecular , Luz , Modelos Animais de Doenças , Relação Estrutura-Atividade
7.
Front Immunol ; 15: 1280877, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38533504

RESUMO

Background/Introduction: Adipose tissue (AT) has been highlighted as a promising reservoir of infection for viruses, bacteria and parasites. Among them is Trypanosoma cruzi, which causes Chagas disease. The recommended treatment for the disease in Brazil is Benznidazole (BZ). However, its efficacy may vary according to the stage of the disease, geographical origin, age, immune background of the host and sensitivity of the strains to the drug. In this context, AT may act as an ally for the parasite survival and persistence in the host and a barrier for BZ action. Therefore, we investigated the immunomodulation of T. cruzi-infected human AT in the presence of peripheral blood mononuclear cells (PBMC) where BZ treatment was added. Methods: We performed indirect cultivation between T. cruzi-infected adipocytes, PBMC and the addition of BZ. After 72h of treatment, the supernatant was collected for cytokine, chemokine and adipokine assay. Infected adipocytes were removed to quantify T. cruzi DNA, and PBMC were removed for immunophenotyping. Results: Our findings showed elevated secretion of interleukin (IL)-6, IL-2 and monocyte chemoattractant protein-1 (MCP-1/CCL2) in the AT+PBMC condition compared to the other controls. In contrast, there was a decrease in tumor necrosis factor (TNF) and IL-8/CXCL-8 in the groups with AT. We also found high adipsin secretion in PBMC+AT+T compared to the treated condition (PBMC+AT+T+BZ). Likewise, the expression of CD80+ and HLA-DR+ in CD14+ cells decreased in the presence of T. cruzi. Discussion: Thus, our findings indicate that AT promotes up-regulation of inflammatory products such as IL-6, IL-2, and MCP-1/CCL2. However, adipogenic inducers may have triggered the downregulation of TNF and IL-8/CXCL8 through the peroxisome proliferator agonist gamma (PPAR-g) or receptor expression. On the other hand, the administration of BZ only managed to reduce inflammation in the microenvironment by decreasing adipsin in the infected culture conditions. Therefore, given the findings, we can see that AT is an ally of the parasite in evading the host's immune response and the pharmacological action of BZ.


Assuntos
Doença de Chagas , Nitroimidazóis , Trypanosoma cruzi , Humanos , Interleucina-8 , Leucócitos Mononucleares , Fator D do Complemento , Interleucina-2/uso terapêutico , Tecido Adiposo , Adipócitos , Fator de Necrose Tumoral alfa/uso terapêutico , Imunidade , Falha de Tratamento
8.
Front Cell Infect Microbiol ; 14: 1297099, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38495650

RESUMO

Introduction: Oral transmission of T. cruzi is probably the most frequent transmission mechanism in wild animals. This observation led to the hypothesis that consuming raw or undercooked meat from animals infected with T. cruzi may be responsible for transmitting the infection. Therefore, the general objective of this study was to investigate host-pathogen interactions between the parasite and gastric mucosa and the role of meat consumption from infected animals in the oral transmission of T. cruzi. Methods: Cell infectivity assays were performed on AGS cells in the presence or absence of mucin, and the roles of pepsin and acidic pH were determined. Moreover, groups of five female Balb/c mice were fed with muscle tissue obtained from mice in the acute phase of infection by the clone H510 C8C3hvir of T. cruzi, and the infection of the fed mice was monitored by a parasitemia curve. Similarly, we assessed the infective capacity of T. cruzi trypomastigotes and amastigotes by infecting groups of five mice Balb/c females, which were infected orally using a nasogastric probe, and the infection was monitored by a parasitemia curve. Finally, different trypomastigote and amastigote inoculums were used to determine their infective capacities. Adhesion assays of T. cruzi proteins to AGS stomach cells were performed, and the adhered proteins were detected by western blotting using monoclonal or polyclonal antibodies and by LC-MS/MS and bioinformatics analysis. Results: Trypomastigote migration in the presence of mucin was reduced by approximately 30%, whereas in the presence of mucin and pepsin at pH 3.5, only a small proportion of parasites were able to migrate (∼6%). Similarly, the ability of TCTs to infect AGS cells in the presence of mucin is reduced by approximately 20%. In all cases, 60-100% of the animals were fed meat from mice infected in the acute phase or infected with trypomastigotes or amastigotes developed high parasitemia, and 80% died around day 40 post-infection. The adhesion assay showed that cruzipain is a molecule of trypomastigotes and amastigotes that binds to AGS cells. LC-MS/MS and bioinformatics analysis, also confirmed that transialidase, cysteine proteinases, and gp63 may be involved in TCTs attachment or invasion of human stomach cells because they can potentially interact with different proteins in the human stomach mucosa. In addition, several human gastric mucins have cysteine protease cleavage sites. Discussion: Then, under our experimental conditions, consuming meat from infected animals in the acute phase allows the T. cruzi infection. Similarly, trypomastigotes and amastigotes could infect mice when administered orally, whereas cysteinyl proteinases and trans-sialidase appear to be relevant molecules in this infective process.


Assuntos
Doença de Chagas , Doenças Transmissíveis , Trypanosoma cruzi , Feminino , Animais , Camundongos , Humanos , Trypanosoma cruzi/metabolismo , Pepsina A/metabolismo , Parasitemia , Modelos Animais de Doenças , Cromatografia Líquida , Espectrometria de Massas em Tandem , Doença de Chagas/parasitologia , Mucinas
9.
Biomed Pharmacother ; 173: 116307, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38401521

RESUMO

Chagas disease (CHD) is the highest economic burden parasitosis worldwide and the most important cardiac infection, without therapeutic alternatives to halt or reverse its progression. In CHD-experimental models, antioxidant and anti-inflammatory compounds have demonstrated therapeutic potential in cardiac dysfunction. Theobroma cacao polyphenols are potent natural antioxidants with cardioprotective and anti-inflammatory action, which are susceptible to degradation, requiring technological approaches to guarantee their protection, stability, and controlled release. Here, 21 cocoa polyphenol-rich microencapsulates were produced by spray-drying and freeze-drying techniques using two wall materials (maltodextrin and gum arabic). Chemical (total and individual phenolic content and antioxidant activity), structural (morphology), and biological parameters (cytotoxicity, trypanocidal, antioxidant, and immunomodulatory activities) were assessed to determine the most efficient microencapsulation conditions on Trypanosoma cruzi-infected myocardioblast and macrophage cells. Significant antiproliferative properties against infected cells (superior to benznidazole) were found in two microencapsulates which also exhibited cardioprotective properties against oxidative stress, inflammation, and cell death.


Assuntos
Cacau , Trypanosoma cruzi , Humanos , Polifenóis/farmacologia , Polifenóis/química , Antioxidantes/farmacologia , Antioxidantes/química , Cacau/química , Anti-Inflamatórios
10.
Protein Expr Purif ; 218: 106458, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38423156

RESUMO

Trypanosoma cruzi is the causative agent of Chagas disease, a global public health problem. New therapeutic drugs and biologics are needed. The TSA-1 recombinant protein of T. cruzi is one such promising antigen for developing a therapeutic vaccine. However, it is overexpressed in E. coli as inclusion bodies, requiring an additional refolding step. As an alternative, in this study, we propose the endogenous cysteine protease inhibitor chagasin as a molecular scaffold to generate chimeric proteins. These proteins will contain combinations of two of the five conserved epitopes (E1 to E5) of TSA-1 in the L4 and L6 chagasin loops. Twenty chimeras (Q1-Q20) were designed, and their solubility was predicted using bioinformatics tools. Nine chimeras with different degrees of solubility were selected and expressed in E. coli BL21 (DE3). Western blot assays with anti-6x-His and anti-chagasin antibodies confirmed the expression of soluble recombinant chimeras. Both theoretically and experimentally, the Q12 (E5-E3) chimera was the most soluble, and the Q20 (E4-E5) the most insoluble protein. Q4 (E5-E1) and Q8 (E5-E2) chimeras were classified as proteins with medium solubility that exhibited the highest yield in the soluble fraction. Notably, Q4 has a yield of 239 mg/L, well above the yield of recombinant chagasin (16.5 mg/L) expressed in a soluble form. The expression of the Q4 chimera was scaled up to a 7 L fermenter obtaining a yield of 490 mg/L. These data show that chagasin can serve as a molecular scaffold for the expression of TSA-1 epitopes in the form of soluble chimeras.


Assuntos
Proteínas de Membrana , Trypanosoma cruzi , Trypanosoma cruzi/genética , Cisteína Endopeptidases/metabolismo , Epitopos/genética , Epitopos/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo
11.
Emerg Microbes Infect ; 13(1): 2315964, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38381980

RESUMO

Chagas Disease is an important neglected tropical disease caused by Trypanosoma cruzi. There is no gold standard for diagnosis and commercial serological tests perform poorly in certain locations. By aligning T. cruzi genomes covering parasite genetic and geographic diversity, we identified highly conserved proteins that could serve as universal antigens for improved diagnosis. Their antigenicity was tested in high-density peptide microarrays using well-characterized plasma samples, including samples presenting true infections but discordant serology. Individual and combination of epitopes were also evaluated in peptide-ELISAs. We identified >1400 highly conserved T. cruzi proteins evaluated in microarrays. Remarkably, T. cruzi positive controls had a different epitope recognition profile compared to serologically discordant samples. In particular, multiple T. cruzi antigens used in current tests and their strain-variants, and novel epitopes thought to be broadly antigenic failed to be recognized by discordant samples. Nonetheless, >2000 epitopes specifically recognized by IgGs from both positive controls and discordant samples were identified. Evaluation of selected peptides in ELISA further illustrated the extensive variation in antibody profiles among subjects and a peptide combination could outperform a commercial ELISA, increasing assay sensitivity from 52.3% to 72.7%. Individual variation in antibody profiles rather than T. cruzi diversity appears to be the main factor driving differences in serological diagnostic performance according to geography, which will be important to further elucidate. ELISA with a combination of peptides recognized by a greater number of individuals could better capture infections, and further development may lead to an optimal antigen mixture for a universal diagnostic assay.


Assuntos
Doença de Chagas , Trypanosoma cruzi , Humanos , Trypanosoma cruzi/genética , Trypanosoma cruzi/química , Antígenos de Protozoários/genética , Doença de Chagas/diagnóstico , Doença de Chagas/parasitologia , Epitopos/genética , Ensaio de Imunoadsorção Enzimática , Peptídeos
12.
mSphere ; 9(2): e0063523, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38315033

RESUMO

Noelia Lander works on cell signaling in American trypanosomes and studies the role of cyclic adenosine monophosphate (cAMP) microdomains in environmental sensing and differentiation. In this mSphere of Influence, Dr. Lander reflects on three research articles in different eukaryotic models that had impacted on the way she thinks about the regulation of cAMP signals in Trypanosoma cruzi, the etiologic agent of Chagas disease. The articles "FRET biosensor uncovers cAMP nano-domains at ß-adrenergic targets that dictate precise tuning of cardiac contractility" (N. C. Surdo, M. Berrera, A. Koschinski, M. Brescia, et al., Nat Commun 8:15031, 2017, https://doi.org/10.1038/ncomms15031), "Cyclic AMP signaling and glucose metabolism mediate pH taxis by African trypanosomes" (S. Shaw, S. Knüsel, D. Abbühl, A. Naguleswaran, et al., Nat Commun 13:603, 2022, https://doi.org/10.1038/s41467-022-28293-w), and "Encystation stimuli sensing is mediated by adenylate cyclase AC2-dependent cAMP signaling in Giardia" (H. W. Shih, G. C. M. Alas, and A. R. Paredez, Nat Commun 14:7245, 2023, https://doi.org/10.1038/s41467-023-43028-1) influenced her current hypothesis that cAMP signals are generated in response to environmental cues leading to changes in membrane fluidity at the flagellar tip and the contractile vacuole complex of T. cruzi, structures where cAMP mediates key cellular processes for developmental progression.


Assuntos
Trypanosoma cruzi , Feminino , Estados Unidos , Humanos , Trypanosoma cruzi/metabolismo , AMP Cíclico/metabolismo
13.
Artigo em Inglês | MEDLINE | ID: mdl-38324876

RESUMO

Multiple myeloma (MM) associated with Chagas disease is rarely described. This disease and its therapy suppress T cell and macrophage functions and increase regulatory T cell function, allowing the increase of parasitemia and the risk of Chagas Disease Reactivation (CDR). We aimed to analyze the role of conventional (cPCR) and quantitative Polymerase Chain Reaction (qPCR) for prospective monitoring of T. cruzi parasitemia, searching for markers of preemptive antiparasitic therapy in MM patients with Chagas disease. Moreover, we investigated the incidence and management of hematological diseases and CDR both inside and outside the transplant setting in the MEDLINE database. We found 293 studies and included 31 of them. Around 1.9-2.0% of patients with Chagas disease were reported in patients undergoing Stem Cell Transplantation. One case of CDR was described in eight cases of MM and Chagas disease. We monitored nine MM and Chagas disease patients, seven under Autologous Stem Cell Transplantation (ASCT), during 44.56±32.10 months (mean±SD) using parasitological methods, cPCR, and qPCR. From these patients, three had parasitemia. In the first, up to 256 par Eq/mL were detected, starting from 28 months after ASCT. The second patient dropped out and died soon after the detection of 161.0 par Eq/mL. The third patient had a positive blood culture. Benznidazole induced fast negativity in two cases; followed by notably lower levels in one of them. Increased T. cruzi parasitemia was related to the severity of the underlying disease. We recommend parasitemia monitoring by qPCR for early introduction of preemptive antiparasitic therapy to avoid CDR.


Assuntos
Doença de Chagas , Transplante de Células-Tronco Hematopoéticas , Mieloma Múltiplo , Nitroimidazóis , Trypanosoma cruzi , Humanos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/complicações , Antiparasitários/uso terapêutico , Parasitemia/tratamento farmacológico , Parasitemia/epidemiologia , Parasitemia/parasitologia , Estudos Prospectivos , Transplante Autólogo , Doença de Chagas/tratamento farmacológico , Doença de Chagas/epidemiologia , Nitroimidazóis/uso terapêutico
14.
Clin Infect Dis ; 78(2): 453-456, 2024 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-37805935

RESUMO

Chagas disease (CD), caused by Trypanosoma cruzi, is underdiagnosed in the United States. Improved screening strategies are needed, particularly for people at risk for life-threatening sequelae of CD, including people with human immunodeficiency virus (HIV, PWH). Here we report results of a CD screening strategy applied at a large HIV clinic serving an at-risk population.


Assuntos
Doença de Chagas , Infecções por HIV , Trypanosoma cruzi , Humanos , Estados Unidos/epidemiologia , HIV , Doença de Chagas/diagnóstico , Doença de Chagas/epidemiologia , Doença de Chagas/complicações , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Infecções por HIV/complicações
15.
Acta Trop ; 251: 107116, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38159713

RESUMO

Neglected tropical diseases (NTD) like Leishmaniasis and trypanosomiasis affect millions of people annually, while currently used antiprotozoal drugs have serious side effects. Drug research based on natural products has shown that microalgae and cyanobacteria are a promising platform of biochemically active compounds with antiprotozoal activity. These unicellular photosynthetic organisms are rich in polyunsaturated fatty acids, pigments including phycocyanin, chlorophylls and carotenoids, polyphenols, bioactive peptides, terpenes, alkaloids, which have proven antioxidant, antimicrobial, antiviral, antiplasmodial and antiprotozoal properties. This review provides up-to-date information regarding ongoing studies on substances synthesized by microalgae and cyanobacteria with notable activity against Leishmania spp., Trypanosoma cruzi, and Trypanosoma brucei, the causative agents of Leishmaniasis, Chagas disease, and human African trypanosomiasis, respectively. Extracts of several freshwater or marine microalgae have been tested on different strains of Leishmania and Trypanosoma parasites. For instance, ethanolic extract of Chlamydomonas reinhardtii and Tetraselmis suecica have biological activity against T. cruzi, due to their high content of carotenoids, chlorophylls, phenolic compounds and flavonoids that are associated with trypanocidal activity. Halophilic Dunaliella salina showed moderate antileishmanial activity that may be attributed to the high ß-carotene content in this microalga. Peptides such as almiramides, dragonamides, and herbamide that are biosynthesized by marine cyanobacteria Lyngbya majuscula were found to have increased activity in micromolar scale IC50 against L. donovani, T. Cruzi, and T. brucei parasites. The cyanobacterial peptides symplocamide and venturamide isolated from Symploca and Oscillatoria species, respectively, and the alkaloid nostocarbonile isolated from Nostoc have shown promising antiprotozoal properties and are being explored for pharmaceutical and medicinal purposes. The discovery of new molecules from microalgae and cyanobacteria with therapeutic potential against Leishmaniasis and trypanosomiasis may address an urgent medical need: effective and safe treatments of NTDs.


Assuntos
Antiprotozoários , Doença de Chagas , Cianobactérias , Leishmania , Leishmaniose , Microalgas , Parasitos , Trypanosoma cruzi , Tripanossomíase , Animais , Humanos , Antiprotozoários/uso terapêutico , Doença de Chagas/tratamento farmacológico , Tripanossomíase/tratamento farmacológico , Leishmaniose/tratamento farmacológico , Carotenoides/farmacologia , Carotenoides/uso terapêutico , Peptídeos
16.
Parasites Hosts Dis ; 61(4): 405-417, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38043536

RESUMO

Chagas disease, caused by Trypanosoma cruzi parasite, is a significant but neglected tropical public health issue in Latin America due to the diversity of its genotypes and pathogenic profiles. This complexity is compounded by the adverse effects of current treatments, underscoring the need for new therapeutic options that employ medicinal plant extracts without negative side effects. Our research aimed to evaluate the trypanocidal activity of Bidens pilosa fractions against epimastigote and trypomastigote stages of T. cruzi, specifically targeting the Brener and Nuevo León strains-the latter isolated from Triatoma gerstaeckeri in General Terán, Nuevo León, México. We processed the plant's aerial parts (stems, leaves, and flowers) to obtain a methanolic extract (Bp-mOH) and fractions with varying solvent polarities. These preparations inhibited more than 90% of growth at concentrations as low as 800 µg/ml for both parasite stages. The median lethal concentration (LC50) values for the Bp-mOH extract and its fractions were below 500 µg/ml. Tests for cytotoxicity using Artemia salina and Vero cells and hemolytic activity assays for the extract and its fractions yielded negative results. The methanol fraction (BPFC3MOH1) exhibited superior inhibitory activity. Its functional groups, identified as phenols, enols, alkaloids, carbohydrates, and proteins, include compounds such as 2-hydroxy-3-methylbenzaldehyde (50.9%), pentadecyl prop-2-enoate (22.1%), and linalool (15.4%). Eight compounds were identified, with a match confirmed by the National Institute of Standards and Technology (NIST-MS) software through mass spectrometry analysis.


Assuntos
Bidens , Doença de Chagas , Trypanosoma cruzi , Animais , Chlorocebus aethiops , Cromatografia Gasosa-Espectrometria de Massas , Metanol/farmacologia , Células Vero , Doença de Chagas/tratamento farmacológico , Extratos Vegetais/farmacologia
17.
Front Immunol ; 14: 1282856, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38124741

RESUMO

Inflammasomes are large protein complexes that, once activated, initiate inflammatory responses by activating the caspase-1 protease. They play pivotal roles in host defense against pathogens. The well-established role of NAIP/NLRC4 inflammasome in bacterial infections involves NAIP proteins functioning as sensors for their ligands. However, recent reports have indicated the involvement of NLRC4 in non-bacterial infections and sterile inflammation, even though the role of NAIP proteins and the exact molecular mechanisms underlying inflammasome activation in these contexts remain to be elucidated. In this study, we investigated the activation of the NAIP/NLRC4 inflammasome in response to Trypanosoma cruzi, the protozoan parasite responsible for causing Chagas disease. This parasite has been previously demonstrated to activate NLRP3 inflammasomes. Here we found that NAIP and NLRC4 proteins are also required for IL-1ß and Nitric Oxide (NO) release in response to T. cruzi infection, with their absence rendering macrophages permissive to parasite replication. Moreover, Nlrc4 -/- and Nlrp3 -/- macrophages presented similar impaired responses to T. cruzi, underscoring the non-redundant roles played by these inflammasomes during infection. Notably, it was the live trypomastigotes rather than soluble antigens or extracellular vesicles (EVs) secreted by them, that activated inflammasomes in a cathepsins-dependent manner. The inhibition of cathepsins effectively abrogated caspase-1 cleavage, IL-1ß and NO release, mirroring the phenotype observed in Nlrc4 -/-/Nlrp3 -/- double knockout macrophages. Collectively, our findings shed light on the pivotal role of the NAIP/NLRC4 inflammasome in macrophage responses to T. cruzi infection, providing new insights into its broader functions that extend beyond bacterial infections.


Assuntos
Infecções Bacterianas , Doença de Chagas , Trypanosoma cruzi , Humanos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Trypanosoma cruzi/metabolismo , Caspase 1/metabolismo , Catepsinas/metabolismo , Macrófagos , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Proteína Inibidora de Apoptose Neuronal/metabolismo
18.
RECIIS (Online) ; 17(4): 867-890, out.-dez. 2023.
Artigo em Português | LILACS | ID: biblio-1532168

RESUMO

A doença de Chagas crônica afeta seis milhões de pessoas em regiões endêmicas, com 30 mil novos casos anuais ­ logo, espaços de divulgação científica são muito importantes para ofertar informações de qualidade à população. As iniciativas envolvendo o controle da doença de Chagas não podem se limitar às pesquisas com enfoque biológico. Este estudo objetiva apresentar um panorama sobre o processo de construção do canal Falamos de Chagas, no YouTube, sua importância para a comunicação, a informação, a educação em saúde e a mobilização social, bem como refletir sobre a qualidade de uma subamostra de vídeos do canal. Trata-se de um estudo qualitativo, dividido em duas fases: criação do canal e análise qualitativa dos vídeos sobre a doença disponíveis no YouTube. Observamos que existe potencial nas redes sociais, enquanto recurso de comunicação, contudo é preciso cautela, uma vez que se faz necessária a certificação da qualidade do material


Chronic Chagas disease affects six million people in endemic regions, with 30,000 new infected cases an-nually ­ thus, initiatives involving science diffusion are relevant to offer qualified information to the people. Chagas disease control initiatives cannot be limited to the level of biological focused research. This study aims to present an overview of the construction process of the YouTube channel Falando de Chagas, its importance for communication, information, health education and social mobilization, as well as to reflect on the quality of a subsample of videos present in the channel. Qualitative in nature, the study was divided into two stages: construction of the channel and qualitative analysis of videos about the disease available on YouTube. We observed that there is potential for social networks as communication resources, but caution is needed in their use, since the quality of the material needs certification


La enfermedad de Chagas crónica afecta seis millones de personas en regiones endémicas, con 30.000 nuevos casos anuales ­ los espacios de divulgación científica son muy importantes para ofrecer información a la población. Las iniciativas de control de la enfermedad de Chagas no pueden limitarse al nivel de investigación con enfoque biológico. El estudio tiene como objetivo presentar un panorama del proceso de construcción del canal Falando de Chagas, en YouTube, su importancia para la comunicación, información, educación en salud y movilización social, así como reflexionar sobre la calidad de una submuestra de videos presentes en la canal. De naturaleza cualitativa, el estudio se dividió en dos fases: construcción del canal y análisis cualitativo de videos sobre la enfermedad disponibles en YouTube. Observamos que existe potencial para las redes sociales como recurso de comunicación, sin embargo, se requiere cautela en su uso, ya que se requiere certificar la calidad del material


Assuntos
Humanos , Trypanosoma cruzi , Educação em Saúde , Doença de Chagas , Mortalidade , Pesquisa Qualitativa , Doenças Negligenciadas , Comunicação em Saúde , Rede Social
19.
Front Immunol ; 14: 1243480, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37915581

RESUMO

Introduction: Toxoplasma gondii is the etiologic agent of toxoplasmosis, a disease that affects about one-third of the human population. Most infected individuals are asymptomatic, but severe cases can occur such as in congenital transmission, which can be aggravated in individuals infected with other pathogens, such as HIV-positive pregnant women. However, it is unknown whether infection by other pathogens, such as Trypanosoma cruzi, the etiologic agent of Chagas disease, as well as one of its proteins, P21, could aggravate T. gondii infection. Methods: In this sense, we aimed to investigate the impact of T. cruzi and recombinant P21 (rP21) on T. gondii infection in BeWo cells and human placental explants. Results: Our results showed that T. cruzi infection, as well as rP21, increases invasion and decreases intracellular proliferation of T. gondii in BeWo cells. The increase in invasion promoted by rP21 is dependent on its binding to CXCR4 and the actin cytoskeleton polymerization, while the decrease in proliferation is due to an arrest in the S/M phase in the parasite cell cycle, as well as interleukin (IL)-6 upregulation and IL-8 downmodulation. On the other hand, in human placental villi, rP21 can either increase or decrease T. gondii proliferation, whereas T. cruzi infection increases T. gondii proliferation. This increase can be explained by the induction of an anti-inflammatory environment through an increase in IL-4 and a decrease in IL-6, IL-8, macrophage migration inhibitory factor (MIF), and tumor necrosis factor (TNF)-α production. Discussion: In conclusion, in situations of coinfection, the presence of T. cruzi may favor the congenital transmission of T. gondii, highlighting the importance of neonatal screening for both diseases, as well as the importance of studies with P21 as a future therapeutic target for the treatment of Chagas disease, since it can also favor T. gondii infection.


Assuntos
Doença de Chagas , Toxoplasmose , Trypanosoma cruzi , Recém-Nascido , Humanos , Feminino , Gravidez , Placenta/patologia , Interleucina-8 , Toxoplasmose/patologia , Doença de Chagas/patologia , Proteínas Recombinantes
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