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1.
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
2.
J Nat Prod ; 87(4): 1067-1074, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38631020

RESUMO

A search for anti-trypanosomal natural compounds from plants collected in El Salvador, a country particularly endemic for Chagas disease, resulted in the isolation of five lignan-type compounds (1-5) from Peperomia pseudopereskiifolia. The lignan derivatives 1, 2, and 4 are new. Their absolute configuration was determined by chemical derivatization. Compounds 1, 5, 6, and 8 exhibited anti-trypanosomal activity against the amastigote form of T. cruzi comparable to that of the existing drug benznidazole.


Assuntos
Lignanas , Peperomia , Tripanossomicidas , Trypanosoma cruzi , Lignanas/farmacologia , Lignanas/química , Lignanas/isolamento & purificação , Trypanosoma cruzi/efeitos dos fármacos , El Salvador , Tripanossomicidas/farmacologia , Tripanossomicidas/química , Tripanossomicidas/isolamento & purificação , Estrutura Molecular , Peperomia/química , Nitroimidazóis/farmacologia , Nitroimidazóis/química , Doença de Chagas/tratamento farmacológico
3.
PLoS One ; 19(4): e0300021, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38635818

RESUMO

Trypanosoma cruzi (T. cruzi) is the causative agent of Chagas' disease, a parasitic infection responsible for significant morbidity and mortality in Latin America. The current treatments have many serious drawbacks and new drugs are urgently required. In the UK, T. cruzi is classified by the Advisory Committee on Dangerous Pathogens (ACDP) as a Hazard Group 3 organism and strict safety practices must be adhered to when handling this pathogen in the laboratory. Validated inactivation techniques are required for safe T. cruzi waste disposal and removal from Containment Level 3 (CL3) facilities for storage, transportation and experimental analysis. Here we assess three T. cruzi. inactivation methods. These include three freeze-thaw cycles, chemical inactivation with Virkon disinfectant, and air drying on Whatman FTA cards (A, B, C, Elute) and on a Mitra microsampling device. After each treatment parasite growth was monitored for 4-6 weeks by microscopic examination. Three freeze-thaw cycles were sufficient to inactivate all T. cruzi CLBrener Luc life cycle stages and Silvio x10/7 A1 large epimastigote cell pellets up to two grams wet weight. Virkon treatment for one hour inactivated T. cruzi Silvio x10/7 subclone A1 and CLBrener Luc both in whole blood and cell culture medium when incubated at a final concentration of 2.5% Virkon, or at ≥1% Virkon when in tenfold excess of sample volume. Air drying also inactivated T. cruzi CLBrener Luc spiked blood when dried on FTA A, B or Elute cards for ≥30 minutes and on a Mitra Microsampler for two hours. However, T. cruzi CLBrener Luc were not inactivated on FTA C cards when dried for up to two hours. These experimentally confirmed conditions provide three validated T. cruzi inactivation methods which can be applied to other related ACDP Hazard Group 2-3 kinetoplastid parasites.


Assuntos
Aminopiridinas , Doença de Chagas , Ácidos Sulfúricos , Trypanosoma cruzi , Humanos , Doença de Chagas/parasitologia , Peróxidos
4.
Front Immunol ; 15: 1342431, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38655255

RESUMO

Chagas disease, caused by Trypanosoma cruzi, remains a serious public health problem worldwide. The parasite was subdivided into six distinct genetic groups, called "discrete typing units" (DTUs), from TcI to TcVI. Several studies have indicated that the heterogeneity of T. cruzi species directly affects the diversity of clinical manifestations of Chagas disease, control, diagnosis performance, and susceptibility to treatment. Thus, this review aims to describe how T. cruzi genetic diversity influences the biology of the parasite and/or clinical parameters in humans. Regarding the geographic dispersion of T. cruzi, evident differences were observed in the distribution of DTUs in distinct areas. For example, TcII is the main DTU detected in Brazilian patients from the central and southeastern regions, where there are also registers of TcVI as a secondary T. cruzi DTU. An important aspect observed in previous studies is that the genetic variability of T. cruzi can impact parasite infectivity, reproduction, and differentiation in the vectors. It has been proposed that T. cruzi DTU influences the host immune response and affects disease progression. Genetic aspects of the parasite play an important role in determining which host tissues will be infected, thus heavily influencing Chagas disease's pathogenesis. Several teams have investigated the correlation between T. cruzi DTU and the reactivation of Chagas disease. In agreement with these data, it is reasonable to suppose that the immunological condition of the patient, whether or not associated with the reactivation of the T. cruzi infection and the parasite strain, may have an important role in the pathogenesis of Chagas disease. In this context, understanding the genetics of T. cruzi and its biological and clinical implications will provide new knowledge that may contribute to additional strategies in the diagnosis and clinical outcome follow-up of patients with Chagas disease, in addition to the reactivation of immunocompromised patients infected with T. cruzi.


Assuntos
Doença de Chagas , Variação Genética , Trypanosoma cruzi , Trypanosoma cruzi/genética , Humanos , Doença de Chagas/imunologia , Doença de Chagas/parasitologia , Animais , Interações Hospedeiro-Parasita/genética , Interações Hospedeiro-Parasita/imunologia
5.
Parasit Vectors ; 17(1): 169, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566228

RESUMO

BACKGROUND: Triatoma garciabesi and T. guasayana are considered secondary vectors of Trypanosoma cruzi and frequently invade rural houses in central Argentina. Wing and head structures determine the ability of triatomines to disperse. Environmental changes exert selective pressures on populations of both species, promoting changes in these structures that could have consequences for flight dispersal. The aim of this study was to investigate the relationship between a gradient of anthropization and phenotypic plasticity in flight-related traits. METHODS: The research was carried out in Cruz del Eje and Ischilín departments (Córdoba, Argentina) and included 423 individuals of the two species of triatomines. To measure the degree of anthropization, a thematic map was constructed using supervised classification, from which seven landscapes were selected, and nine landscape metrics were extracted and used in a hierarchical analysis. To determine the flight capacity and the invasion of dwellings at different levels of anthropization for both species, entomological indices were calculated. Digital images of the body, head and wings were used to measure linear and geometric morphometric variables related to flight dispersion. One-way ANOVA and canonical variate analysis (CVA) were used to analyze differences in size and shape between levels of anthropization. Procrustes variance of shape was calculated to analyze differences in phenotypic variation in heads and wings. RESULTS: Hierarchical analysis was used to classify the landscapes into three levels of anthropization: high, intermediate and low. The dispersal index for both species yielded similar results across the anthropization gradient. However, in less anthropized landscapes, the density index was higher for T. garciabesi. Additionally, in highly anthropized landscapes, females and males of both species exhibited reduced numbers. Regarding phenotypic changes, the size of body, head and wings of T. garciabesi captured in the most anthropized landscapes was greater than for those captured in less anthropized landscapes. No differences in body size were observed in T. guasayana collected in the different landscapes. However, males from highly anthropized landscapes had smaller heads and wings than those captured in less anthropized landscapes. Both wing and head shapes varied between less and more anthropogenic environments in both species. CONCLUSIONS: Results of the study indicate that the flight-dispersal characteristics of T. garciabesi and T. guasayana changed in response to varying degrees of anthropization.


Assuntos
Doença de Chagas , Triatoma , Trypanosoma cruzi , Humanos , Masculino , Animais , Feminino , Triatoma/fisiologia , População Rural , Argentina , Análise de Variância
6.
PLoS Negl Trop Dis ; 18(4): e0011452, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38568999

RESUMO

BACKGROUND: Immune response of triatomines plays an important role in the success or failure of transmission of T. cruzi. Studies on parasite-vector interaction have shown the presence of trypanolytic factors and have been observed to be differentially expressed among triatomines, which affects the transmission of some T. cruzi strains or DTUs (Discrete Typing Units). METHODOLOGY/PRINCIPAL FINDINGS: Trypanolytic factors were detected in the hemolymph and saliva of R. prolixus against epimastigotes and trypomastigotes of the Y strain (T. cruzi II). To identify the components of the immune response that could be involved in this lytic activity, a comparative proteomic analysis was carried out, detecting 120 proteins in the hemolymph of R. prolixus and 107 in R. colombiensis. In salivary glands, 1103 proteins were detected in R. prolixus and 853 in R. colombiensis. A higher relative abundance of lysozyme, prolixin, nitrophorins, and serpin as immune response proteins was detected in the hemolymph of R. prolixus. Among the R. prolixus salivary proteins, a higher relative abundance of nitrophorins, lipocalins, and triabins was detected. The higher relative abundance of these immune factors in R. prolixus supports their participation in the lytic activity on Y strain (T. cruzi II), but not on Dm28c (T. cruzi I), which is resistant to lysis by hemolymph and salivary proteins of R. prolixus due to mechanisms of evading oxidative stress caused by immune factors. CONCLUSIONS/SIGNIFICANCE: The lysis resistance observed in the Dm28c strain would be occurring at the DTU I level. T. cruzi I is the DTU with the greatest geographic distribution, from the south of the United States to central Chile and Argentina, a distribution that could be related to resistance to oxidative stress from vectors. Likewise, we can say that lysis against strain Y could occur at the level of DTU II and could be a determinant of the vector inability of these species to transmit T. cruzi II. Future proteomic and transcriptomic studies on vectors and the interactions of the intestinal microbiota with parasites will help to confirm the determinants of successful or failed vector transmission of T. cruzi DTUs in different parts of the Western Hemisphere.


Assuntos
Doença de Chagas , Rhodnius , Trypanosoma cruzi , Animais , Trypanosoma cruzi/genética , Rhodnius/parasitologia , Hemolinfa , Proteômica , Glândulas Salivares , Proteínas e Peptídeos Salivares/genética , Proteínas e Peptídeos Salivares/metabolismo , Fatores Imunológicos/metabolismo
7.
Chem Biol Drug Des ; 103(4): e14525, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38627214

RESUMO

An early exploration of the benzothiazole class against two kinetoplastid parasites, Leishmania infantum and Trypanosoma cruzi, has been performed after the identification of a benzothiazole derivative as a suitable antileishmanial initial hit. The first series of derivatives focused on the acyl fragment of its class, evaluating diverse linear and cyclic, alkyl and aromatic substituents, and identified two other potent compounds, the phenyl and cyclohexyl derivatives. Subsequently, new compounds were designed to assess the impact of the presence of diverse substituents on the benzothiazole ring or the replacement of the endocyclic sulfur by other heteroatoms. All compounds showed relatively low cytotoxicity, resulting in decent selectivity indexes for the most active compounds. Ultimately, the in vitro ADME properties of these compounds were assessed, revealing a satisfying water solubility, gastrointestinal permeability, despite their low metabolic stability and high lipophilicity. Consequently, compounds 5 and 6 were identified as promising hits for further hit-to-lead exploration within this benzothiazole class against L. infantum, thus providing promising starting points for the development of antileishmanial candidates.


Assuntos
Antiprotozoários , Leishmania infantum , Trypanosoma cruzi , Antiprotozoários/farmacologia , Benzotiazóis/farmacologia
8.
Traffic ; 25(4): e12935, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38629580

RESUMO

The protozoan parasites Plasmodium falciparum, Leishmania spp. and Trypanosoma cruzi continue to exert a significant toll on the disease landscape of the human population in sub-Saharan Africa and Latin America. Control measures have helped reduce the burden of their respective diseases-malaria, leishmaniasis and Chagas disease-in endemic regions. However, the need for new drugs, innovative vaccination strategies and molecular markers of disease severity and outcomes has emerged because of developing antimicrobial drug resistance, comparatively inadequate or absent vaccines, and a lack of trustworthy markers of morbid outcomes. Extracellular vesicles (EVs) have been widely reported to play a role in the biology and pathogenicity of P. falciparum, Leishmania spp. and T. cruzi ever since they were discovered. EVs are secreted by a yet to be fully understood mechanism in protozoans into the extracellular milieu and carry a cargo of diverse molecules that reflect the originator cell's metabolic state. Although our understanding of the biogenesis and function of EVs continues to deepen, the question of how EVs in P. falciparum, Leishmania spp. and T. cruzi can serve as targets for a translational agenda into clinical and public health interventions is yet to be fully explored. Here, as a consortium of protozoan researchers, we outline a plan for future researchers and pose three questions to direct an EV's translational agenda in P. falciparum, Leishmania spp. and T. cruzi. We opine that in the long term, executing this blueprint will help bridge the current unmet needs of these medically important protozoan diseases in sub-Saharan Africa and Latin America.


Assuntos
Doença de Chagas , Vesículas Extracelulares , Leishmania , Parasitos , Trypanosoma cruzi , Animais , Humanos , Doença de Chagas/epidemiologia , Doença de Chagas/parasitologia
9.
Int J Mol Sci ; 25(7)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38612484

RESUMO

Twenty 2-(4-alkyloxyphenyl)-imidazolines and 2-(4-alkyloxyphenyl)-imidazoles were synthesized, with the former being synthesized in two steps by using MW and ultrasonication energy, resulting in good to excellent yields. Imidazoles were obtained in moderate yields by oxidizing imidazolines with MnO2 and MW energy. In response to the urgent need to treat neglected tropical diseases, a set of 2-(4-alkyloxyphenyl)- imidazolines and imidazoles was tested in vitro on Leishmania mexicana and Trypanosoma cruzi. The leishmanicidal activity of ten compounds was evaluated, showing an IC50 < 10 µg/mL. Among these compounds, 27-31 were the most active, with IC50 values < 1 µg/mL (similar to the reference drugs). In the evaluation on epimastigotes of T. cruzi, only 30 and 36 reached an IC50 < 1 µg/mL, showing better inhibition than both reference drugs. However, compounds 29, 33, and 35 also demonstrated attractive trypanocidal activities, with IC50 values < 10 µg/mL, similar to the values for benznidazole and nifurtimox.


Assuntos
Antiprotozoários , Doença de Chagas , Imidazolinas , Leishmania mexicana , Trypanosoma cruzi , Humanos , Imidazóis/farmacologia , Compostos de Manganês , Óxidos , Antiprotozoários/farmacologia
10.
Int J Mol Sci ; 25(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38612650

RESUMO

Chagas disease (CD) is a vector-borne Neglected Zoonotic Disease (NZD) caused by a flagellate protozoan, Trypanosoma cruzi, that affects various mammalian species across America, including humans and domestic animals. However, due to an increase in population movements and new routes of transmission, T. cruzi infection is presently considered a worldwide health concern, no longer restricted to endemic countries. Dogs play a major role in the domestic cycle by acting very efficiently as reservoirs and allowing the perpetuation of parasite transmission in endemic areas. Despite the significant progress made in recent years, still there is no vaccine against human and animal disease, there are few drugs available for the treatment of human CD, and there is no standard protocol for the treatment of canine CD. In this review, we highlight human and canine Chagas Disease in its different dimensions and interconnections. Dogs, which are considered to be the most important peridomestic reservoir and sentinel for the transmission of T. cruzi infection in a community, develop CD that is clinically similar to human CD. Therefore, an integrative approach, based on the One Health concept, bringing together the advances in genomics, immunology, and epidemiology can lead to the effective development of vaccines, new treatments, and innovative control strategies to tackle CD.


Assuntos
Doenças dos Animais , Doença de Chagas , Doenças do Cão , Trypanosoma cruzi , Humanos , Cães , Animais , Doença de Chagas/epidemiologia , Doença de Chagas/veterinária , Animais Domésticos , Doenças do Cão/epidemiologia , Mamíferos
11.
Parasitol Res ; 123(4): 181, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38602595

RESUMO

Chagas disease (CD), caused by the complex life cycle parasite Trypanosoma cruzi, is a global health concern and impacts millions globally. T. cruzi's genetic variability is categorized into discrete typing units (DTUs). Despite their widespread presence in the Americas, a comprehensive understanding of their impact on CD is lacking. This study aims to analyze life cycle traits across life cycle stages, unraveling DTU dynamics. Metacyclogenesis curves were generated, inducing nutritional stress in epimastigotes of five DTUs (TcI (MG), TcI (DA), TcII(Y), TcIII, TcIV, and TcVI), resulting in metacyclic trypomastigotes. Infection dynamics in Vero cells from various DTUs were evaluated, exploring factors like amastigotes per cell, cell-derived trypomastigotes, and infection percentage. Statistical analyses, including ANOVA tests, identified significant differences. Varying onset times for metacyclogenesis converged on the 7th day. TcI (MG) exhibited the highest metacyclogenesis potential. TcI (DA) stood out, infecting 80% of cells within 24 h. TcI demonstrated the highest potential in both metacyclogenesis and infection among the strains assessed. Intra-DTU diversity was evident among TcI strains, contributing to a comprehensive understanding of Trypanosoma cruzi dynamics and genetic diversity.


Assuntos
Doença de Chagas , Trypanosoma cruzi , Chlorocebus aethiops , Animais , Trypanosoma cruzi/genética , Células Vero , Fenótipo
12.
Methods Mol Biol ; 2801: 87-95, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38578415

RESUMO

Large-pore channels allow the exchange of ions and molecules between the intra- and extracellular compartments. These channels are structures formed by several protein families with little or no evolutionary linkages that include connexins (Cxs), pannexins (Panxs), innexins (Inxs), CALHM1, and LRRC8 proteins. Recently, we have described the unnexins (Unxs) proteins expressed in Trypanosoma cruzi (T. cruzi) that also is like to form large-pore channels at the plasma membrane. In this chapter, we describe a dye uptake method for evaluating the unnexin-formed channel function in T. cruzi, as well as the methods for evaluating their participation in the transformation of trypomastigotes into amastigotes. These methods can facilitate understanding the role of large-pore channels in the parasite's biology.


Assuntos
Trypanosoma cruzi , Trypanosoma cruzi/metabolismo , Conexinas/metabolismo , Transporte Biológico
13.
Vet Parasitol Reg Stud Reports ; 49: 101003, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38462304

RESUMO

Despite multiple screening efforts to identify exposures to Trypanosoma cruzi, in dogs across southern USA, no published studies could be found involving client owned dogs in the North Texas Metroplex area. Therefore, a limited screen was conducted for client owned dogs, seeking routine or preventative care, from participating veterinary practices in the greater Dallas-Fort Worth (DFW) Metroplex from 2019 to 2021. Participants, with owner consent, ranged in age, breed, and length of time at recorded residence. Ninety-nine samples were acquired from participating veterinary practices, initially assessed with the Chagas StatPak, and positive samples were confirmed with IFA (indirect fluorescent antibody test) at the Texas Veterinary Medical Diagnostic Lab (TVMDL), College Station, Texas. Six samples were positive with the StatPak and only two were confirmed positive with IFA. Both animals were senior (10 and 8 years) with no owner reports of previous cardiac issues. The results appear reasonable within the context of previous studies and the seropositivity rate of 2% (n = 99) for client owned dogs included in this study are lower than previously reported rates for shelter dogs from the North Texas area.


Assuntos
Doença de Chagas , Doenças do Cão , Trypanosoma cruzi , Animais , Cães , Doença de Chagas/diagnóstico , Doença de Chagas/epidemiologia , Doença de Chagas/veterinária , Texas/epidemiologia , Habitação , Doenças do Cão/diagnóstico , Doenças do Cão/epidemiologia
15.
Am J Trop Med Hyg ; 110(4): 663-668, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38452392

RESUMO

Bolivia has one of the highest burdens of Chagas disease in the world. Vertical transmission from mother to infant accounts for a growing number of cases. We performed a systematic review of articles assessing the prevalence of Chagas disease in pregnant women and rates of vertical transmission to infants in Bolivia. Studies were not excluded based on year of publication or language. Random-effects analyses were performed to estimate a pooled prevalence of maternal Chagas disease and pooled vertical transmission rate. Our search yielded 21 articles describing over 400,000 cases of Chagas disease among pregnant women in Bolivia. The reported prevalence of maternal Chagas disease ranged from 17.3% to 64.5%, with a pooled prevalence of 33.0% (95% CI, 27.4-38.7%). The prevalence of maternal Chagas disease trended down over time (P = 0.006), decreasing by approximately 25% to 30% over the last 40 years. Vertical transmission rates ranged from 2.0% to 13% with a pooled average of 6.2% (95% CI, 4.4-7.5%); rates did not significantly change over time. Our study is the first systematic review and meta-analysis of Chagas disease maternal prevalence and vertical transmission in Bolivia. Our findings indicate that maternal Chagas disease has fallen in prevalence but still affects 20% to 30% of pregnant women and poses a considerable risk of vertical transmission. Pregnant women and infants are an important target for public health interventions to limit the mortality and morbidity of Chagas disease and to reduce intergenerational spread.


Assuntos
Doença de Chagas , Trypanosoma cruzi , Lactente , Gravidez , Humanos , Feminino , Prevalência , Bolívia/epidemiologia , Doença de Chagas/epidemiologia , Transmissão Vertical de Doenças Infecciosas , Mães
16.
Rev Soc Bras Med Trop ; 57: e007032024, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38537000

RESUMO

BACKGROUND: Chagas disease, a zoonosis transmitted mainly by hematophagous insects of the subfamily Triatominae, is caused by Trypanosoma cruzi, classified into six discrete typing units (DTUs: TcI-TcVI and Tcbat). METHODS: Insect vectors were collected from 84 human dwellings in the municipality of Santo Domingo Tehuantepec, Oaxaca, Mexico; 4.76% were infested. DTUs were determined using conventional and nested PCR. RESULTS: The infection rate was 43.6%. All insects were infected with TcI while one specimen showed mixed infection with TcII. CONCLUSIONS: This is the first report of T. cruzi mixed infection in Triatoma phyllosoma, its main vector in the study region.


Assuntos
Doença de Chagas , Coinfecção , Triatoma , Trypanosoma cruzi , Animais , Humanos , Trypanosoma cruzi/genética , México , Genótipo
17.
PLoS Negl Trop Dis ; 18(3): e0011997, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38489395

RESUMO

BACKGROUND: Chagas disease (CD), caused by the parasite Trypanosoma cruzi, is the most important endemic anthropozoonosis in Argentina. Since 2010, the World Health Organization has highlighted the urgent need to validate diagnostic systems that allow rapid detection of T. cruzi, infection in primary healthcare centers. Serological rapid diagnostic tests (RDTs) for T. cruzi, infection could be used to improve case management, as RDTs do not require specialized laboratories or highly trained staff to use them. We aimed to generate unbiased performance data of RDTs in Argentina, to evaluate their usefulness for improving T. cruzi, diagnosis rates. METHODS AND PRINCIPAL FINDINGS: This is a retrospective, laboratory-based, diagnostic evaluation study to estimate the clinical sensitivity/specificity of four commercially available RDTs for T. cruzi, using the Chagas disease diagnostic algorithm currently used in Argentina as the reference standard. In total, 400 serum samples were tested, 200 from individuals with chronic T. cruzi infection and 200 from individuals not infected with T. cruzi. All results were registered as the agreement of at least two operators who were blinded to the reference standard results. The sensitivity estimates ranged from 92.5-100% (95% confidence interval (CI) lower bound 87.9-98.2%); for specificity, the range was 76-96% (95% CI lower bound 69.5-92.3%). Most RDTs evaluated showed performances comparable with the reference standard method, showing almost perfect concordance (Kappa 0.76-0.92). CONCLUSIONS: Our study demonstrates that, under controlled laboratory conditions, commercially available RDTs for CD have a performance comparable to the Argentinian diagnostic algorithm, which is based on laboratory-based serological tests. For the next stage of our work, the RDTs will be evaluated in real-world settings.


Assuntos
Doença de Chagas , Trypanosoma cruzi , Humanos , Argentina/epidemiologia , Estudos Retrospectivos , População Urbana , Testes de Diagnóstico Rápido , Doença de Chagas/diagnóstico , Doença de Chagas/epidemiologia , Anticorpos , Sensibilidade e Especificidade , Anticorpos Antiprotozoários
18.
Neuroimmunomodulation ; 31(1): 78-88, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38527434

RESUMO

BACKGROUND: The brain and the immune systems represent the two primary adaptive systems within the body. Both are involved in a dynamic process of communication, vital for the preservation of mammalian homeostasis. This interplay involves two major pathways: the hypothalamic-pituitary-adrenal axis and the sympathetic nervous system. SUMMARY: The establishment of infection can affect immunoneuroendocrine interactions, with functional consequences for immune organs, particularly the thymus. Interestingly, the physiology of this primary organ is not only under the control of the central nervous system (CNS) but also exhibits autocrine/paracrine regulatory circuitries mediated by hormones and neuropeptides that can be altered in situations of infectious stress or chronic inflammation. In particular, Chagas disease, caused by the protozoan parasite Trypanosoma cruzi (T. cruzi), impacts upon immunoneuroendocrine circuits disrupting thymus physiology. Here, we discuss the most relevant findings reported in relation to brain-thymic connections during T. cruzi infection, as well as their possible implications for the immunopathology of human Chagas disease. KEY MESSAGES: During T. cruzi infection, the CNS influences thymus physiology through an intricate network involving hormones, neuropeptides, and pro-inflammatory cytokines. Despite some uncertainties in the mechanisms and the fact that the link between these abnormalities and chronic Chagasic cardiomyopathy is still unknown, it is evident that the precise control exerted by the brain over the thymus is markedly disrupted throughout the course of T. cruzi infection.


Assuntos
Encéfalo , Doença de Chagas , Timo , Humanos , Doença de Chagas/imunologia , Doença de Chagas/fisiopatologia , Animais , Encéfalo/imunologia , Timo/imunologia , Timo/fisiologia , Trypanosoma cruzi/fisiologia , Trypanosoma cruzi/imunologia , Sistema Hipotálamo-Hipofisário/imunologia , Sistema Hipotálamo-Hipofisário/metabolismo , Sistema Hipotálamo-Hipofisário/fisiopatologia , Neuroimunomodulação/fisiologia , Neuroimunomodulação/imunologia , Sistema Hipófise-Suprarrenal/imunologia , Sistema Hipófise-Suprarrenal/fisiopatologia , Sistema Hipófise-Suprarrenal/metabolismo
19.
mBio ; 15(4): e0031924, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38441981

RESUMO

Trypanosoma cruzi is the etiologic agent of the most prevalent human parasitic disease in Latin America, Chagas disease. Its genome is rich in multigenic families that code for virulent antigens and are present in the rapidly evolving genomic compartment named Disruptive. DNA replication is a meticulous biological process in which flaws can generate mutations and changes in chromosomal and gene copy numbers. Here, integrating high-throughput and single-molecule analyses, we were able to identify Predominant, Flexible, and Dormant Orc1Cdc6-dependent origins as well as Orc1Cdc6-independent origins. Orc1Cdc6-dependent origins were found in multigenic family loci, while independent origins were found in the Core compartment that contains conserved and hypothetical protein-coding genes, in addition to multigenic families. In addition, we found that Orc1Cdc6 density is related to the firing of origins and that Orc1Cdc6-binding sites within fired origins are depleted of a specific class of nucleosomes that we previously categorized as dynamic. Together, these data suggest that Orc1Cdc6-dependent origins may contribute to the rapid evolution of the Disruptive compartment and, therefore, to the success of T. cruzi infection and that the local epigenome landscape is also involved in this process.IMPORTANCETrypanosoma cruzi, responsible for Chagas disease, affects millions globally, particularly in Latin America. Lack of vaccine or treatment underscores the need for research. Parasite's genome, with virulent antigen-coding multigenic families, resides in the rapidly evolving Disruptive compartment. Study sheds light on the parasite's dynamic DNA replication, discussing the evolution of the Disruptive compartment. Therefore, the findings represent a significant stride in comprehending T. cruzi's biology and the molecular bases that contribute to the success of infection caused by this parasite.


Assuntos
Doença de Chagas , Trypanosoma cruzi , Humanos , Trypanosoma cruzi/genética , Origem de Replicação , Doença de Chagas/parasitologia , Dosagem de Genes , Cromossomos
20.
PLoS Pathog ; 20(3): e1012012, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38457443

RESUMO

Small molecules (less than 1,500 Da) include major biological signals that mediate host-pathogen-microbiome communication. They also include key intermediates of metabolism and critical cellular building blocks. Pathogens present with unique nutritional needs that restrict pathogen colonization or promote tissue damage. In parallel, parts of host metabolism are responsive to immune signaling and regulated by immune cascades. These interactions can trigger both adaptive and maladaptive metabolic changes in the host, with microbiome-derived signals also contributing to disease progression. In turn, targeting pathogen metabolic needs or maladaptive host metabolic changes is an important strategy to develop new treatments for infectious diseases. Trypanosoma cruzi is a single-celled eukaryotic pathogen and the causative agent of Chagas disease, a neglected tropical disease associated with cardiac and intestinal dysfunction. Here, we discuss the role of small molecules during T. cruzi infection in its vector and in the mammalian host. We integrate these findings to build a theoretical interpretation of how maladaptive metabolic changes drive Chagas disease and extrapolate on how these findings can guide drug development.


Assuntos
Doença de Chagas , Microbiota , Trypanosoma cruzi , Animais , Humanos , Interação Gene-Ambiente , Doença de Chagas/metabolismo , Trypanosoma cruzi/metabolismo , Progressão da Doença , Mamíferos
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