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1.
PLoS One ; 16(1): e0244710, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33400707

RESUMO

Memory impairment has been associated with chronic Chagas disease (CD), a neglected tropical disease caused by the protozoan parasite Trypanosoma cruzi. In degenerative diseases, memory loss has been associated with increased oxidative stress, revealed as enhanced lipid peroxidation, in the cerebral cortex. Benznidazole (Bz), a trypanocidal drug efficient to reduce blood parasite load in the acute and chronic phases of infection, showed controversial effects on heart disease progression, the main clinical manifestation of CD. Here, we evaluated whether C57BL/6 mice infected with the Colombian type I T. cruzi strain present memory deficit assessed by (i) the novel object recognition task, (ii) the open field test and (iii) the aversive shock evoked test, at 120 days post infection (dpi). Next, we tested the effects of Bz therapy (25mg/Kg/day, for 30 consecutive days) on memory evocation, and tried to establish a relation between memory loss, parasite load and oxidative stress in the central nervous system (CNS). At 120 dpi, T. cruzi-infected mice showed memory impairment, compared with age-matched non-infected controls. Bz therapy (from 120 to 150 dpi) hampered the progression of habituation and aversive memory loss and, moreover, reversed memory impairment in object recognition. In vehicle-administered infected mice, neuroinflammation was absent albeit rare perivascular mononuclear cells were found in meninges and choroid plexus. Bz therapy abrogated the infiltration of the CNS by inflammatory cells, and reduced parasite load in hippocampus and cerebral cortex. At 120 and 150 dpi, lipid peroxidation was increased in the hippocampus and cortex tissue extracts. Notably, Bz therapy reduced levels of lipid peroxidation in the cerebral cortex. Therefore, in experimental chronic T. cruzi infection Bz therapy improved memory loss, in association with reduction of parasite load and oxidative stress in the CNS, providing a new perspective to improve the quality of life of Chagas disease patients.


Assuntos
Doença de Chagas/tratamento farmacológico , Disfunção Cognitiva/tratamento farmacológico , Nitroimidazóis/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Tripanossomicidas/uso terapêutico , Trypanosoma cruzi/efeitos dos fármacos , Animais , Doença de Chagas/complicações , Doença de Chagas/metabolismo , Doença de Chagas/fisiopatologia , Doença Crônica , Cognição/efeitos dos fármacos , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/fisiopatologia , Feminino , Camundongos Endogâmicos C57BL , Carga Parasitária
2.
Int J Mol Sci ; 21(24)2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33322418

RESUMO

Trypanosoma cruzi dysregulates the gene expression profile of primary human cardiomyocytes (PHCM) during the early phase of infection through a mechanism which remains to be elucidated. The role that small non-coding RNAs (sncRNA) including PIWI-interacting RNA (piRNA) play in regulating gene expression during the early phase of infection is unknown. To understand how T. cruzi dysregulate gene expression in the heart, we challenged PHCM with T. cruzi trypomastigotes and analyzed sncRNA, especially piRNA, by RNA-sequencing. The parasite induced significant differential expression of host piRNAs, which can target and regulate the genes which are important during the early infection phase. An average of 21,595,866 (88.40%) of clean reads mapped to the human reference genome. The parasite induced 217 unique piRNAs that were significantly differentially expressed (q ≥ 0.8). Of these differentially expressed piRNAs, 6 were known and 211 were novel piRNAs. In silico analysis showed that some of the dysregulated known and novel piRNAs could target and potentially regulate the expression of genes including NFATC2, FOS and TGF-ß1, reported to play important roles during T. cruzi infection. Further evaluation of the specific functions of the piRNAs in the regulation of gene expression during the early phase of infection will enhance our understanding of the molecular mechanism of T. cruzi pathogenesis. Our novel findings constitute the first report that T. cruzi can induce differential expression of piRNAs in PHCM, advancing our knowledge about the involvement of piRNAs in an infectious disease model, which can be exploited for biomarker and therapeutic development.


Assuntos
RNA Interferente Pequeno/metabolismo , Trypanosoma cruzi/metabolismo , Animais , Doença de Chagas/metabolismo , Humanos , Miócitos Cardíacos/metabolismo
3.
Medicine (Baltimore) ; 99(51): e23773, 2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33371145

RESUMO

ABSTRACT: Chagas disease affects approximately 7 million people, causing disability and mortality in the most productive life stages of infected individuals. Considering the lifestyle of the world population, metabolic syndrome is a synergistic factor for an increased cardiovascular risk of patients with Chagas disease.This study transversally evaluated the metabolic and immunological profiles of patients with indeterminate (IF) and cardiac (CF) forms of Chagas disease and their correlations with left ventricular dysfunction (LVD).Clinical and electrical bioimpedance analysis, levels of cytokines (interferon [IFN]-γ, tumor necrosis factor [TNF]-α, interleukin [IL]-17, IL-10, and IL-33) and adipocytokines (adiponectin, leptin, and resistin), metabolic syndrome components, and brain natriuretic peptide (BNP) levels were assessed in 57 patients (13 IF and 44 CF) with a mean age of 61.63 ±â€Š12.1 years. Chest x-ray, electrocardiogram, and echocardiogram were performed to classify the clinical forms.The CF group had a higher number of individuals with metabolic syndrome components blood pressure altered, while more participants in the CF group with LVD had low high-density lipoprotein (HDL) levels. The IF group had more participants with a higher waist-to-hip ratio (WHR). No significant difference was observed between metabolic syndrome, cytokine and adipocytokine level, and clinical forms of the disease or in relation to LVD.Individuals with the IF showed metabolic and immunological profiles compatible with increased disease control, whereas those with CF showed marked inflammatory immune response.


Assuntos
Doença de Chagas/imunologia , Doença de Chagas/metabolismo , Adiponectina/análise , Adiponectina/sangue , Idoso , Análise de Variância , Biomarcadores/análise , Biomarcadores/sangue , Feminino , Cardiopatias/imunologia , Cardiopatias/metabolismo , Humanos , Interleucina-10/análise , Interleucina-10/sangue , Interleucina-17/análise , Interleucina-17/biossíntese , Interleucina-33/análise , Interleucina-33/sangue , Leptina/análise , Leptina/sangue , Masculino , Pessoa de Meia-Idade , Resistina/análise , Resistina/sangue , Estatísticas não Paramétricas
4.
PLoS Pathog ; 16(8): e1008781, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32810179

RESUMO

Chagas disease is caused by Trypanosoma cruzi, a protozoan parasite that has a heterogeneous population composed of a pool of strains with distinct characteristics, including variable levels of virulence. In previous work, transcriptome analyses of parasite genes after infection of human foreskin fibroblasts (HFF) with virulent (CL Brener) and non-virulent (CL-14) clones derived from the CL strain, revealed a reduced expression of genes encoding parasite surface proteins in CL-14 compared to CL Brener during the final steps of the intracellular differentiation from amastigotes to trypomastigotes. Here we analyzed changes in the expression of host genes during in vitro infection of HFF cells with the CL Brener and CL-14 strains by analyzing total RNA extracted from cells at 60 and 96 hours post-infection (hpi) with each strain, as well as from uninfected cells. Similar transcriptome profiles were observed at 60 hpi with both strains compared to uninfected samples. However, at 96 hpi, significant differences in the number and expression levels of several genes, particularly those involved with immune response and cytoskeleton organization, were observed. Further analyses confirmed the difference in the chemokine/cytokine signaling involved with the recruitment and activation of immune cells such as neutrophils upon T. cruzi infection. These findings suggest that infection with the virulent CL Brener strain induces a more robust inflammatory response when compared with the non-virulent CL-14 strain. Importantly, the RNA-Seq data also exposed an unexplored role of fibroblasts as sentinel cells that may act by recruiting neutrophils to the initial site of infection. This role for fibroblasts in the regulation of the inflammatory response during infection by T. cruzi was corroborated by measurements of levels of different chemokines/cytokines during in vitro infection and in plasma from Chagas disease patients as well as by neutrophil activation and migration assays.


Assuntos
Doença de Chagas/metabolismo , Fibroblastos , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Ativação de Neutrófilo , Neutrófilos , Trypanosoma cruzi/metabolismo , Doença de Chagas/genética , Doença de Chagas/patologia , Fibroblastos/metabolismo , Fibroblastos/parasitologia , Fibroblastos/patologia , Humanos , Neutrófilos/metabolismo , Neutrófilos/parasitologia , Neutrófilos/patologia , Trypanosoma cruzi/genética , Trypanosoma cruzi/patogenicidade , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
5.
Life Sci ; 258: 118137, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32712299

RESUMO

AIMS: Chagas disease is a neglected tropical disease. The ability of Trypanosoma cruzi to survive within phagocytes is likely a critical factor for T. cruzi dissemination in the host. For control of the parasite load and host survival, macrophage action is required. Concanavalin-A (Con-A) presents properties that modulate immune functions and protect hosts from several experimental infectious diseases. Here, we evaluated the effects of Con-A on peritoneal macrophages as well as on the course of experimental infection by T. cruzi. MAIN METHODS: BALB/c mice, a susceptible model for T. cruzi infection, were treated with Con-A via the intraperitoneal route and 3 days later infected with T. cruzi. We quantified parasitemia, cytokines and nitric oxide (NO). Peritoneal exudate and macrophages were collected for macrophage phenotyping and cell viability, NO and cytokine detection, as well as for T. cruzi internalization and release index determination. KEY FINDINGS: Con-A treatment induced IL-17a and NO production by cells from the peritoneal cavity, and M1 marker expression predominated on peritoneal macrophages. These cells are also more prone to producing TNF-α, IL-6 and NO when infected by T. cruzi and show high trypanocidal capacity. Due to a hostile peritoneal microenvironment caused by Con-A, which induces macrophage cNOS and iNOS expression, infected BALB/c mice showed reduced parasitemia and an increased survival rate. SIGNIFICANCE: We conclude that Con-A can induce peritoneal M1 macrophage polarization to increase trypanocidal activity, resulting in ameliorated systemic infection in a susceptible experimental model.


Assuntos
Polaridade Celular , Doença de Chagas/patologia , Concanavalina A/farmacologia , Interleucina-17/metabolismo , Macrófagos Peritoneais/patologia , Macrófagos Peritoneais/parasitologia , Óxido Nítrico/metabolismo , Trypanosoma cruzi/fisiologia , Animais , Polaridade Celular/efeitos dos fármacos , Doença de Chagas/metabolismo , Feminino , Macrófagos Peritoneais/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Óxido Nítrico Sintase Tipo II/metabolismo , Parasitemia/metabolismo , Parasitemia/patologia , Trypanosoma cruzi/efeitos dos fármacos
6.
Infect Dis Poverty ; 9(1): 51, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32393333

RESUMO

BACKGROUND: Chagas disease is endemic in Latin America and still represents an important public health problem in the region. Chronic cardiomyopathy is the most significant chronic form due to its association with morbidity and mortality. The last decade has seen increasing evidence that inflammatory cytokines and chemokines are responsible for the generation of inflammatory infiltrate and tissue damage, with chronic chagasic cardiomyopathy patients presenting a pro-inflammatory immune response. Although studies have evaluated the role of chemokines in experimental T. cruzi infection, few have addressed their systemic profile, especially for human infection and in aging populations. The present work aimed to use the data from a large population based study of older adults, conducted in an endemic area for Chagas disease, to examine the association between serum levels of cytokines and chemokines, T. cruzi infection and electrocardiogram (ECG) abnormality. METHODS: The present work evaluated serum levels of CCL2, CXCL9, CXCL10, CCL5, CXCL8, IL-1ß, IL-6, TNF, IL-12 and IL-10 by Flow Cytometric Bead Array assay (CBA) and the results expressed in pg/ml. The baseline survey started in January 1st 1997, with 1284 participants of an aged population-based cohort. Participants signed an informed consent at baseline and at each subsequent visit and authorized death certificate and medical records verification. RESULTS: Our results demonstrated that Chagas disease patients had higher serum levels of CXCL9, CXCL10 and IL-1ß and lower serum levels of CCL5 than non-infected subjects. Moreover, our data demonstrated that CXCL9 and CXCL10 increased in an age-dependent profile in Chagas disease patients. CONCLUSION: Together, this study provided evidences that serum biomarkers increase along the age continuum and may have potential implications for establishing clinical management protocols and therapeutic intervention in Chagas disease patients.


Assuntos
Envelhecimento , Doença de Chagas/metabolismo , Quimiocina CXCL10/metabolismo , Quimiocina CXCL9/metabolismo , Trypanosoma cruzi/fisiologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Brasil , Estudos de Coortes , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
PLoS Pathog ; 16(4): e1008474, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32315358

RESUMO

Trypanosoma cruzi (T. cruzi) is the etiological agent of Chagas cardiomyopathy. In the present study, we investigated the role of extracellular vesicles (Ev) in shaping the macrophage (Mφ) response in progressive Chagas disease (CD). We purified T. cruzi Ev (TcEv) from axenic parasite cultures, and T. cruzi-induced Ev (TEv) from the supernatants of infected cells and plasma of acutely and chronically infected wild-type and Parp1-/- mice. Cultured (Raw 264.7) and bone-marrow Mφ responded to TcEV and TEv with a profound increase in the expression and release of TNF-α, IL-6, and IL-1ß cytokines. TEv produced by both immune (Mφ) and non-immune (muscle) cells were proinflammatory. Chemical inhibition or genetic deletion of PARP1 (a DNA repair enzyme) significantly depressed the TEv-induced transcriptional and translational activation of proinflammatory Mφ response. Oxidized DNA encapsulated by TEv was necessary for PARP1-dependent proinflammatory Mφ response. Inhibition studies suggested that DNA-sensing innate immune receptors (cGAS>>TLR9) synergized with PARP1 in signaling the NFκB activation, and inhibition of PARP1 and cGAS resulted in >80% inhibition of TEv-induced NFκB activity. Histochemical studies showed intense inflammatory infiltrate associated with profound increase in CD11b+CD68+TNF-α+ Mφ in the myocardium of CD wild-type mice. In comparison, chronically infected Parp1-/- mice exhibited low-to-moderate tissue inflammation, >80% decline in myocardial infiltration of TNF-α+ Mφ, and no change in immunoregulatory IL-10+ Mφ. We conclude that oxidized DNA released with TEv signal the PARP1-cGAS-NF-κB pathway of proinflammatory Mφ activation and worsens the chronic inflammatory pathology in CD. Small molecule antagonists of PARP1-cGAS signaling pathway would potentially be useful in reprogramming the Mφ activation and controlling the chronic inflammation in CD.


Assuntos
Doença de Chagas/metabolismo , Vesículas Extracelulares/metabolismo , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , NF-kappa B/metabolismo , Nucleotidiltransferases/metabolismo , Poli(ADP-Ribose) Polimerase-1/metabolismo , Animais , Cardiomiopatia Chagásica/imunologia , Cardiomiopatia Chagásica/metabolismo , Citocinas/imunologia , Citocinas/metabolismo , Feminino , Interleucina-1beta/imunologia , Interleucina-1beta/metabolismo , Interleucina-6/imunologia , Interleucina-6/metabolismo , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Knockout , NF-kappa B/imunologia , Nucleotidiltransferases/imunologia , Poli(ADP-Ribose) Polimerase-1/imunologia , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/imunologia , Trypanosoma cruzi/metabolismo , Trypanosoma cruzi/patogenicidade , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-32074218

RESUMO

Proinflammatory and inflammatory mediators induced by Trypanosoma cruzi infection increase the oxidative stress, generating toxicity for cells targeting mitochondria of different tissues. We studied the activity of citrate synthase and complexes I-IV of respiratory chain in mitochondria of blood lymphomonocyte fraction, from albino Swiss mice infected with different isolates of T. cruzi , during Chagas disease evolution. Complexes I-IV were modified in infected groups (p<0.05) in all the stages, and an inflammatory process of different magnitudes was detected in the heart and skeletal muscle according to the isolate. The citrate synthase activity presented modifications in the SGO Z12 and the Tulahuen group (p<0.05). Hearts showed fiber fragmentation and fibrosis; skeletal muscle presented inflammatory infiltrates and in the Tulahuen infected group, there were also amastigote nests. The inflammatory processes produced an oxidative stress that induced different alterations of mitochondrial enzymes activities in the lymphomonocyte fraction that can be detected by a simple blood extraction, suggesting that they could be used as disease markers, especially in the indeterminate phase of Chagas disease.


Assuntos
Doença de Chagas/enzimologia , Citrato (si)-Sintase/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Mitocôndrias/enzimologia , Animais , Doença de Chagas/metabolismo , Doença de Chagas/fisiopatologia , Modelos Animais de Doenças , Progressão da Doença , Masculino , Mitocôndrias/parasitologia , Mitocôndrias/patologia , Parasitemia
9.
Clin Immunol ; 212: 108346, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31954803

RESUMO

Previous studies showed that circulating autoantibodies against M2 muscarinic receptors (anti-M2R Ab) are associated with decreased cardiac parasympathetic modulation in patients with chronic Chagas disease (CD). Here we investigated whether the exposure of M2R to such antibodies could impair agonist-induced receptor activation, leading to the inhibition of associated signaling pathways. Preincubation of M2R-expressing HEK 293T cells with serum IgG fractions from chagasic patients with cardiovascular dysautonomia, followed by the addition of carbachol, resulted in the attenuation of agonist-induced Gi protein activation and arrestin-2 recruitment. These effects were not mimicked by the corresponding Fab fractions, suggesting that they occur through receptor crosslinking. IgG autoantibodies did not enhance M2R/arrestin interaction or promote M2R internalization, suggesting that their inhibitory effects are not likely a result of short-term receptor regulation. Rather, these immunoglobulins could function as negative allosteric modulators of acetylcholine-mediated responses, thereby contributing to the development of parasympathetic dysfunction in patients with CD.


Assuntos
Autoanticorpos/imunologia , Doenças do Sistema Nervoso Autônomo/imunologia , Doença de Chagas/imunologia , Receptor Muscarínico M2/imunologia , Adulto , Idoso , Regulação Alostérica , Autoanticorpos/metabolismo , Autoanticorpos/farmacologia , Doenças do Sistema Nervoso Autônomo/etiologia , Doenças do Sistema Nervoso Autônomo/metabolismo , Doenças do Sistema Nervoso Autônomo/fisiopatologia , Carbacol/farmacologia , Doença de Chagas/complicações , Doença de Chagas/metabolismo , Doença de Chagas/fisiopatologia , Agonistas Colinérgicos/farmacologia , Feminino , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo , Células HEK293 , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Receptor Muscarínico M2/efeitos dos fármacos , Receptor Muscarínico M2/metabolismo , beta-Arrestina 1/metabolismo
10.
Eur J Pharm Sci ; 145: 105234, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31978590

RESUMO

Benznidazole (BZ) tablets are a unique form of treatment available for treating Chagas disease. Development of a liquid formulation containing BZ easy to administer orally for the treatment of paediatric patients, particularly for newborns is urgently required, with the same efficacy, safety and suitable biopharmaceutical properties as BZ tablets. Self-emulsifying drug delivery systems (SEDDS) may improve bioavailability of drugs such as BZ, which have poor water solubility and low permeability. In this context, the aim of this work was to develop a liquid BZ-SEDDS formulation as an alternative to tablets and to evaluate its cytotoxicity in different host cell lines and its efficacy in experimental Trypanosoma cruzi infection in mice. The optimized SEDDS formulation (25 mg/ml of BZ) induced no cytotoxicity in H9c2, HepG2 and Caco2 cells in vitro at 25 µM level. BZ-SEDDS and free-BZ showed similar in vitro trypanocidal activity in H9c2 cells infected by T. cruzi Y strain, with IC50 values of 2.10 ± 0.41 µM and 1.29 ± 0.01 µM for BZ and BZ-SEDDS, respectively. A follow up of efficacy in an acute model of infected mice resulted in the same percentage of cure (57%) for both free-BZ and BZ-SEDDS- groups according to established parameters. Furthermore, no additional in vivo toxicity was observed in animals treated with BZ-SEDDS. Taken together, in vitro and in vivo data of BZ-SEDDS showed that the incorporation of BZ into SEDDS does not alter its potency, efficacy and safety. Thus, BZ-SEDDS can be a more practical and personalized orally administered liquid dosage form compared to suspension of crushed BZ-tablets to treat newborn and young children by emulsifying SEDDS in different aqueous liquids with advantage of dosing flexibility.


Assuntos
Doença de Chagas/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos , Emulsificantes/administração & dosagem , Nitroimidazóis/administração & dosagem , Tripanossomicidas/administração & dosagem , Animais , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Doença de Chagas/metabolismo , Formas de Dosagem , Relação Dose-Resposta a Droga , Emulsificantes/química , Emulsificantes/metabolismo , Feminino , Células Hep G2 , Humanos , Camundongos , Nitroimidazóis/química , Nitroimidazóis/metabolismo , Ratos , Tripanossomicidas/química , Tripanossomicidas/metabolismo
12.
PLoS Negl Trop Dis ; 14(1): e0007945, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31895927

RESUMO

Chagas disease, also known as American trypanosomiasis, is a potentially life-threatening illness caused by the protozoan parasite, Trypanosoma cruzi, and is transmitted by triatomine insects during its blood meal. Proliferative epimastigotes forms thrive inside the insects in the presence of heme (iron protoporphyrin IX), an abundant product of blood digestion, however little is known about the metabolic outcome of this signaling molecule in the parasite. Trypanosomatids exhibit unusual gene transcription employing a polycistronic transcription mechanism through trans-splicing that regulates its life cycle. Using the Deep Seq transcriptome sequencing we characterized the heme induced transcriptome of epimastigotes and determined that most of the upregulated genes were related to glucose metabolism inside the glycosomes. These results were supported by the upregulation of glycosomal isoforms of PEPCK and fumarate reductase of heme-treated parasites, implying that the fermentation process was favored. Moreover, the downregulation of mitochondrial gene enzymes in the presence of heme also supported the hypothesis that heme shifts the parasite glycosomal glucose metabolism towards aerobic fermentation. These results are examples of the environmental metabolic plasticity inside the vector supporting ATP production, promoting epimastigotes proliferation and survival.


Assuntos
Perfilação da Expressão Gênica , Heme/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Trypanosoma cruzi/metabolismo , Animais , Doença de Chagas/metabolismo , Genes Mitocondriais , Glucose/metabolismo , Insetos Vetores/parasitologia , Microcorpos/metabolismo , Transdução de Sinais , Transcrição Genética , Triatominae/parasitologia , Trypanosoma cruzi/genética , Trypanosoma cruzi/crescimento & desenvolvimento
13.
Transfusion ; 60(2): 343-350, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31804727

RESUMO

BACKGROUND: Patients with sickle cell disease (SCD) often require red blood cell (RBC) transfusion for clinical complications, so may be exposed to transfusion-transmitted infections (TTIs). The prevalence of markers for human immunodeficiency virus (HIV), hepatitis C virus (HCV) and B (HBV), human T-cell lymphotropic virus (HTLV-1/2), Chagas disease, and syphilis in an SCD cohort in Brazil were studied. STUDY DESIGN AND METHODS: Clinical history, interview data, blood samples, and medical chart review data were collected during cohort enrollment from November 2013 to May 2015. Serologic markers of infection were assessed. Standard measures of statistical association were calculated, and multivariable models were developed for the most prevalent infections to identify associated factors. RESULTS: Infection markers were evident in 5.2% (144/2779) of the enrolled cohort. Anti-HCV was detected in 69 (2.5%), syphilis antibodies in 34 (1.2%), anti-HTLV-1/2 in 17 (0.6%), HBV surface antigen in 13 (0.5%), Chagas disease antibodies in 13 (0.5%), and anti-HIV in 8 (0.3%) of participants. Factors associated with increased odds of being anti-HCV reactive were older age, illegal drug use, increasing number of RBCs, more than three pain crises in the previous year, and geographic location. Syphilis was associated with older age, females, and smoking history. CONCLUSION: HCV infection was more common in older patients who may have received RBCs before testing was performed on donations, suggesting possible historic transfusion transmission. The cohort showed decreasing rates of infections and a reduction in transfusion transmission markers in younger patients compared to historical literature except for syphilis, indicating contemporary reduced risk of TTI.


Assuntos
Anemia Falciforme/epidemiologia , Transfusão de Sangue/métodos , Doenças Sexualmente Transmissíveis/epidemiologia , Adulto , Anemia Falciforme/virologia , Brasil , Doença de Chagas/metabolismo , Doença de Chagas/virologia , Estudos de Coortes , Feminino , HIV/patogenicidade , Hepacivirus/patogenicidade , Vírus da Hepatite B/patogenicidade , Hepatite C/epidemiologia , Hepatite C/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Doenças Sexualmente Transmissíveis/virologia , Sífilis/epidemiologia , Sífilis/virologia , Adulto Jovem
14.
Parasitol Res ; 119(1): 333-337, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31788770

RESUMO

Chagas disease (CD) is a tropical zoonosis caused by the protozoan Trypanosoma cruzi. Severe autonomic dysfunction like reduced cardiac catecholamine-containing or acetylcholinesterase-positive innervation have been reported in CD. Renin-angiotensin system (RAS) seems to participate in the regulation of adrenal catecholamine secretion by adrenal medullary chromaffin cells, which might be dependent of nitric oxide (NO) pathways. To investigate the levels of RAS components in the adrenal gland during the acute infection with Y strain T. cruzi and in response to acute administration of an inhibitor of the enzyme NO synthase, L-NAME. Male Holtzman rats were inoculated intraperitoneally with Y strain T. cruzi and received L-NAME or tap water from one day before the infection until 13 or 17 days post-inoculation (dpi). The concentration of RAS molecules in the adrenal tissue was evaluated by ELISA immunoassay. Angiotensin converting enzyme 1 (ACE1) levels were significantly lower at 17 dpi when compared to 13 dpi. No significant differences were found compared with baseline, and no changes were detected in adrenal tissue levels of angiotensin converting enzyme 2 (ACE2), angiotensin II, or angiotensin-(1-7). Moreover, the treatment with L-NAME did not influence the levels of RAS components in adrenal tissue during the course of T. cruzi infection. We provided the first evidence that levels of RAS molecules change in the adrenal gland during acute phase of T. cruzi infection. Future studies are necessary to fully address the role of NO in RAS-associated adrenal gland function in CD.


Assuntos
Glândulas Suprarrenais/metabolismo , Doença de Chagas/metabolismo , Óxido Nítrico/metabolismo , Sistema Renina-Angiotensina/fisiologia , Trypanosoma cruzi/fisiologia , Animais , Modelos Animais de Doenças , Masculino , NG-Nitroarginina Metil Éster/administração & dosagem , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Peptidil Dipeptidase A/metabolismo , Ratos , Ratos Sprague-Dawley
15.
Eur J Med Chem ; 186: 111877, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31771829

RESUMO

Chagas disease is one of the main neglected diseases in the world, being endemic in 21 countries of Latin America. This disease has become a global health problem due to migration of infected people non-endemic countries. Even though this disease affects millions of people, only two drugs are approved for its treatment, benznidazole and nifurtimox, and both have several limitations. We have previously reported the synthesis and biological activity against T. cruzi of polysubstituted quinolines analogous to natural products. Herein, we present the synthesis of rationally-based novel analogous of this family of compounds. All the evaluated compounds presented trypanocidal activity. Three of them (6, 7 and 10) stand out for their selectivity indexes. Ethyl 2-((4-benzyl-1,4-diazepan-1-yl)methyl)-6-chloro-4-phenylquinoline-3-carboxylate (compound 10) was found to display anti-parasite activity, presenting the highest selectivity index. Apart from controlling in vivo the parasitemia levels, compound 10 was able to prevent tissue inflammation, a key factor to prevent the progression to chronic chagasic cardiomyopathy. The therapeutic effects of compound 10 are promising and suggest a new possibility to treat this disease.


Assuntos
Doença de Chagas/tratamento farmacológico , Quinolinas/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Doença de Chagas/metabolismo , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Feminino , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Camundongos , Camundongos Endogâmicos C3H , Estrutura Molecular , Testes de Sensibilidade Parasitária , Quinolinas/síntese química , Quinolinas/química , Relação Estrutura-Atividade , Tripanossomicidas/síntese química , Tripanossomicidas/química , Células Vero
16.
Eur J Cell Biol ; 99(1): 151060, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31812279

RESUMO

Trypanosoma cruzi causes Chagas disease, a neglected illness that affects millions of people worldwide, especially in Latin America. The balance between biochemical pathways triggered by the parasite and host cells response will ultimately define the progression of a life-threatening disease, justifying the efforts to understand cellular mechanisms for infection restrain. In this interaction, parasite and host cells are affected by different physiological responses as autophagy modulation, which could be under intense cellular stress, such as nutrient deprivation, hormone depletion, or infection. Autophagy is a constitutive pathway that leads to degradation of macromolecules and cellular structures and may induce cell death. In Trypanosoma cruzi infection, the relevance of host autophagy is controversial regarding in vitro parasite intracellular life cycle. In the present study, we evaluated host cell autophagy during T. cruzi infection in phagocytic and non-professional phagocytic cells. We described that the presence of the parasite increased the number of LC3 puncta, a marker for autophagy, in cardiac cells and peritoneal macrophages in vitro. The induction of host autophagy decreased infection in macrophages in early and late time-periods. We suggest that starved phagocytic cells reduced internalization, also confirmed by inert particles and dead trypomastigotes. Whereas, in cardiac cells, starvation-induced autophagy decreased lipid droplets and infection in later time-point, by reducing parasite differentiation/proliferation. In ATG5 knockout MEF cells, we confirmed our hypothesis of autophagy machinery activation during parasite internalization, increasing infection. Our data suggest that host autophagy downregulates T. cruzi infection through impairing parasite intracellular life cycle, reducing the infection in primary culture cells.


Assuntos
Autofagia , Doença de Chagas/metabolismo , Animais , Sobrevivência Celular , Células Cultivadas , Doença de Chagas/patologia , Gotículas Lipídicas/química , Gotículas Lipídicas/metabolismo , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Trypanosoma cruzi/isolamento & purificação , Trypanosoma cruzi/metabolismo
17.
J Enzyme Inhib Med Chem ; 35(1): 21-30, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-31619095

RESUMO

Trypanosoma cruzi carbonic anhydrase (TcCA) has recently emerged as an interesting target for the design of new compounds to treat Chagas disease. In this study we report the results of a structure-based virtual screening campaign to identify novel and selective TcCA inhibitors. The combination of properly validated computational methodologies such as comparative modelling, molecular dynamics and docking simulations allowed us to find high potency hits, with KI values in the nanomolar range. The compounds also showed trypanocidal effects against T. cruzi epimastigotes and trypomastigotes. All the candidates are selective for inhibiting TcCA over the human isoform CA II, which is encouraging in terms of possible therapeutic safety and efficacy.


Assuntos
Inibidores da Anidrase Carbônica/farmacologia , Anidrases Carbônicas/metabolismo , Doença de Chagas/tratamento farmacológico , Ciclamatos/farmacologia , Tripanossomicidas/farmacologia , Inibidores da Anidrase Carbônica/síntese química , Inibidores da Anidrase Carbônica/química , Doença de Chagas/metabolismo , Ciclamatos/síntese química , Ciclamatos/química , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Humanos , Modelos Moleculares , Estrutura Molecular , Testes de Sensibilidade Parasitária , Relação Estrutura-Atividade , Tripanossomicidas/síntese química , Tripanossomicidas/química , Trypanosoma cruzi/efeitos dos fármacos , Trypanosoma cruzi/enzimologia
18.
Sci Rep ; 9(1): 18885, 2019 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-31827186

RESUMO

We evaluated the influence of metabolic syndrome (MS) on acute Trypanosoma cruzi infection. Obese Swiss mice, 70 days of age, were subjected to intraperitoneal infection with 5 × 102 trypomastigotes of the Y strain. Cardiovascular, oxidative, inflammatory, and metabolic parameters were evaluated in infected and non-infected mice. We observed higher parasitaemia in the infected obese group (IOG) than in the infected control group (ICG) 13 and 15 days post-infection. All IOG animals died by 19 days post-infection (dpi), whereas 87.5% of the ICG survived to 30 days. Increased plasma nitrite levels in adipose tissue and the aorta were observed in the IOG. Higher INF-γ and MCP-1 concentrations and lower IL-10 concentrations were observed in the IOG compared to those in the ICG. Decreased insulin sensitivity was observed in obese animals, which was accentuated after infection. Higher parasitic loads were found in adipose and hepatic tissue, and increases in oxidative stress in cardiac, hepatic, and adipose tissues were characteristics of the IOG group. Thus, MS exacerbates experimental Chagas disease, resulting in greater damage and decreased survival in infected animals, and might be a warning sign that MS can influence other pathologies.


Assuntos
Tecido Adiposo/metabolismo , Doença de Chagas/metabolismo , Inflamação/metabolismo , Fígado/metabolismo , Síndrome Metabólica/metabolismo , Miocárdio/metabolismo , Estresse Oxidativo/fisiologia , Tecido Adiposo/patologia , Animais , Doença de Chagas/complicações , Doença de Chagas/patologia , Citocinas/sangue , Modelos Animais de Doenças , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Inflamação/complicações , Inflamação/patologia , Resistência à Insulina/fisiologia , Fígado/patologia , Masculino , Síndrome Metabólica/complicações , Síndrome Metabólica/patologia , Camundongos , Miocárdio/patologia , Trypanosoma cruzi
19.
Int Immunopharmacol ; 77: 105961, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31685438

RESUMO

We investigated the immunomodulatory, antiparasitic and cardioprotective effects of a sesquiterpene lactone (SL) administered alone or combined with benznidazole (Bz), in a murine model of Chagas' disease by in vitro and in vivo assays. Antiparasitic and cytotoxic potential of tagitinin C (SL) and Bz were tested in vitro against T. cruzi epimastigotes and cardiomyocytes. Swiss mice challenged with T. cruzi were also treated for 20 days with tagitinin C (10 mg/kg) alone and combined with Bz (100 mg/kg). Tagitinin C exhibited a higher antiparasitic (IC50: 1.15 µM) and cytotoxic (CC50 at 6.54 µM) potential than Bz (IC50: 35.81 µM and CC50: 713.5 µM, respectively). When combined, these drugs presented an addictive interaction, determining complete suppression of parasitemia and parasitological cure in all infected mice (100%) compared to those receiving Bz alone (70%). Anti-T. cruzi immunoglobulin G, and pro-inflammatory cytokines IFN-γ and TNF-α levels were reduced in animals treated with tagitinin C combined with Bz, while IL-10 production was unaffected. Heart inflammation was undetectable in 90% of the animals receiving this combination, while only 50% of the animals receiving Bz alone showed no evidence of myocarditis. Together, our findings indicated that the combination of tagitinin C and Bz exerts potent antiparasitic, immunomodulatory and cardioprotective effects. Due to the remarkable suppression of parasitemia and high parasitological cure, this combination was superior to Bz monotherapy, indicating a high potential for the treatment of Chagas's disease.


Assuntos
Antiparasitários/farmacologia , Cardiotônicos/farmacocinética , Fatores Imunológicos/farmacologia , Lactonas/farmacologia , Sesquiterpenos/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Cardiotônicos/farmacologia , Linhagem Celular , Doença de Chagas/tratamento farmacológico , Doença de Chagas/metabolismo , Doença de Chagas/parasitologia , Citocinas/metabolismo , Feminino , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/parasitologia , Camundongos , Miocardite/metabolismo , Miocardite/parasitologia , Nitroimidazóis/farmacologia , Parasitemia/tratamento farmacológico , Parasitemia/metabolismo , Parasitemia/parasitologia , Ratos , Fator de Necrose Tumoral alfa/metabolismo
20.
PLoS One ; 14(11): e0225386, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31756194

RESUMO

Chagas disease is caused by the protozoan Trypanosoma cruzi, affecting around 8 million people worldwide. After host cell invasion, the infective trypomastigote form remains 2-4 hours inside acidic phagolysosomes to differentiate into replicative amastigote form. In vitro acidic-pH-induced axenic amastigogenesis was used here to study this step of the parasite life cycle. After three hours of trypomastigote incubation in amastigogenesis promoting acidic medium (pH 5.0) or control physiological pH (7.4) medium samples were subjected to three rounds of centrifugation followed by ultrafiltration of the supernatants. The resulting exoproteome samples were trypsin digested and analysed by nano flow liquid chromatography coupled to tandem mass spectrometry. Computational protein identification searches yielded 271 and 483 protein groups in the exoproteome at pH 7.4 and pH 5.0, respectively, with 180 common proteins between both conditions. The total amount and diversity of proteins released by parasites almost doubled upon acidic incubation compared to control. Overall, 76.5% of proteins were predicted to be secreted by classical or non-classical pathways and 35.1% of these proteins have predicted transmembrane domains. Classical secretory pathway analysis showed an increased number of mucins and mucin-associated surface proteins after acidic incubation. However, the number of released trans-sialidases and surface GP63 peptidases was higher at pH 7.4. Trans-sialidases and mucins are anchored to the membrane and exhibit an enzyme-substrate relationship. In general, mucins are glycoproteins with immunomodulatory functions in Chagas disease, present mainly in the epimastigote and trypomastigote surfaces and could be enzymatically cleaved and released in the phagolysosome during amastigogenesis. Moreover, evidence for flagella discard during amastigogenesis are addressed. This study provides the first comparative analysis of the exoproteome during amastigogenesis, and the presented data evidence the dynamism of its profile in response to acidic pH-induced differentiation.


Assuntos
Doença de Chagas/parasitologia , Proteômica/métodos , Proteínas de Protozoários/metabolismo , Trypanosoma cruzi/patogenicidade , Doença de Chagas/metabolismo , Cromatografia Líquida , Células HeLa , Interações Hospedeiro-Parasita , Humanos , Concentração de Íons de Hidrogênio , Estágios do Ciclo de Vida , Espectrometria de Massas em Tandem , Trypanosoma cruzi/metabolismo
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