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1.
Onderstepoort J Vet Res ; 91(1): e1-e6, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38426744

RESUMO

Trypanosomosis is a disease complex which affects both humans and animals in sub-Saharan Africa, transmitted by the tsetse fly and distributed within the tsetse belt of Africa. But some trypanosome species, for example, Trypanosoma brucei evansi, T. vivax, T. theileri and T. b. equiperdum are endemic outside the tsetse belt of Africa transmitted by biting flies, for example, Tabanus and Stomoxys, or venereal transmission, respectively. Trypanocidal drugs remain the principal method of animal trypanosomosis control in most African countries. However, there is a growing concern that their effectiveness may be severely curtailed by widespread drug resistance. A minimum number of six male cattle calves were recruited for the study. They were randomly grouped into two (T. vivax and T. congolense groups) of three calves each. One calf per group served as a control while two calves were treatment group. They were inoculated with 105 cells/mL parasites in phosphate buffered solution (PBS) in 2 mL. When parasitaemia reached 1 × 107.8 cells/mL trypanosomes per mL in calves, treatment was instituted with 20 mL (25 mg/kg in 100 kg calf) ascofuranone (AF) for treatment calves, while the control ones were administered a placebo (20 mL PBS) intramuscularly. This study revealed that T. vivax was successfully cleared by AF but the T. congolense group was not cleared effectively.Contribution: There is an urgent need to develop new drugs which this study sought to address. It is suggested that the AF compound can be developed further to be a sanative drug for T. vivax in non-tsetse infested areas like South Americas.


Assuntos
Sesquiterpenos , Tripanossomicidas , Tripanossomíase Africana , Animais , Bovinos , Masculino , Sesquiterpenos/farmacologia , Sesquiterpenos/uso terapêutico , Tripanossomicidas/farmacologia , Tripanossomicidas/uso terapêutico , Trypanosoma , Tripanossomíase Africana/tratamento farmacológico , Tripanossomíase Africana/veterinária , Tripanossomíase Africana/epidemiologia , Moscas Tsé-Tsé/parasitologia
2.
Bioorg Chem ; 146: 107288, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38521013

RESUMO

Nitroimidazole compounds are well-known bioactive substances, and the structural activity relationship has been reported whereby the position of the nitro group within the imidazole ring has a large influence on the activity. This study focuses on synthesising new trypanocidal agents from the hybridisation of metronidazole with different natural phenols (eugenol, dihydroeugenol and guaiacol). Two different coupling methodologies have been explored in order to analyse the influence of the connector on bioactivity: i) classic direct esterification (AD compounds) and ii) "click" chemistry using a triazole connector (AC compounds). The in vitro trypanocidal tests show good results for both AC and AD hybrid compounds against both epimastigote and trypomastigote forms of T. cruzi. In silico studies showed positive data for most of the synthesised compounds and, in general present low toxicological risks. The AC compounds present lower ClogP (lipophilicity) values than those found for the AD series and higher TPSA (topological polar surface area) values, suggesting lower lipophilicity may be related to the presence of the triazole connector. The AD series compounds have higher Drug Score values than the AC series derivatives, suggesting better general properties for a pharmacological action.


Assuntos
Doença de Chagas , Tripanossomicidas , Trypanosoma cruzi , Humanos , Metronidazol/farmacologia , Metronidazol/uso terapêutico , Tripanossomicidas/química , Eugenol , Doença de Chagas/tratamento farmacológico , Triazóis/uso terapêutico , Relação Estrutura-Atividade
3.
Sci Rep ; 14(1): 6972, 2024 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-38521853

RESUMO

This study compared effects of diminazene aceturate (berenil), commonly used to treat domestic animals infected with Trypanosoma evansi, with the hemolymph of Sarcophaga argyostoma larva. The hemolymph may be acting as a possible natural alternative to berenil, based on immunomodulation mediated inflammatory response. Inflammatory mediators and histopathological changes in liver, kidney, and spleen of albino mice experimentally infected with T. evansi were studied. Mice were divided into five groups: G1, uninfected, untreated (negative control); G2, T. evansi infected (positive control); G3, infected and treated with berenil; G4, infected and treated with hemolymph; G5, infected and treated with hemolymph 3 days before infection (prophylactic group). Animals in (G4) and (G5) exhibited a significant overall reduction in serum levels of IFN-γ. However, the reduction in TNF-α and IL-6 levels was more limited compared to (G2) and (G3). Notably, an elevation in IL-10 levels was observed compared to animals in other groups. Furthermore, the groups treated with hemolymph demonstrated an alleviation of T. evansi infection in contrast to the other groups. This study highlights that the administration of Sarcophaga argyostoma larval hemolymph at a dosage of 0.5 ml/kg significantly inhibited T. evansi organisms in vivo, showcasing a pronounced trypanocidal effect.


Assuntos
Diminazena/análogos & derivados , Sarcofagídeos , Tripanossomicidas , Trypanosoma , Camundongos , Animais , Tripanossomicidas/farmacologia , Hemolinfa
4.
Int J Parasitol Drugs Drug Resist ; 24: 100529, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38461700

RESUMO

Earlier evidences showed that diglycosyl diselenides are active against the infective stage of African trypanosomes (top hits IC50 0.5 and 1.5 µM) but poorly selective (selectivity index <10). Here we extended the study to 33 new seleno-glycoconjugates with the aim to improve potency and selectivity. Three selenoglycosides and three glycosyl selenenylsulfides displayed IC50 against bloodstream Trypanosoma brucei in the sub-µM range (IC50 0.35-0.77 µM) and four of them showed an improved selectivity (selectivity index >38-folds vs. murine and human macrohages). For the glycosyl selenylsulfides, the anti-trypanosomal activity was not significantly influenced by the nature of the moiety attached to the sulfur atom. Except for a quinoline-, and to a minor extent a nitro-derivative, the most selective hits induced a rapid (within 60 min) and marked perturbation of the LMWT-redox homeostasis. The formation of selenenylsulfide glycoconjugates with free thiols has been identified as a potential mechanism involved in this process.


Assuntos
Tripanossomicidas , Trypanosoma brucei brucei , Trypanosoma , Tripanossomíase Africana , Animais , Camundongos , Humanos , Homeostase , Oxirredução , Tripanossomíase Africana/tratamento farmacológico , Tripanossomicidas/farmacologia , Tripanossomicidas/uso terapêutico
5.
Eur J Med Chem ; 268: 116162, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38394930

RESUMO

Human African trypanosomiasis (HAT), or sleeping sickness, is a neglected tropical disease with current treatments marred by severe side effects or delivery issues. To identify novel classes of compounds for the treatment of HAT, high throughput screening (HTS) had previously been conducted on bloodstream forms of T. b. brucei, a model organism closely related to the human pathogens T. b. gambiense and T. b. rhodesiense. This HTS had identified a number of structural classes with potent bioactivity against T. b. brucei (IC50 ≤ 10 µM) with selectivity over mammalian cell-lines (selectivity index of ≥10). One of the confirmed hits was an aroyl guanidine derivative. Deemed to be chemically tractable with attractive physicochemical properties, here we explore this class further to develop the SAR landscape. We also report the influence of the elucidated SAR on parasite metabolism, to gain insight into possible modes of action of this class. Of note, two sub-classes of analogues were identified that generated opposing metabolic responses involving disrupted energy metabolism. This knowledge may guide the future design of more potent inhibitors, while retaining the desirable physicochemical properties and an excellent selectivity profile of the current compound class.


Assuntos
Parasitos , Tripanossomicidas , Trypanosoma brucei brucei , Trypanosoma , Tripanossomíase Africana , Animais , Humanos , Tripanossomicidas/química , Trypanosoma brucei rhodesiense , Guanidina/farmacologia , Tripanossomíase Africana/tratamento farmacológico , Tripanossomíase Africana/parasitologia , Guanidinas/farmacologia , Metabolismo Energético , Mamíferos
6.
J Med Chem ; 67(5): 3437-3447, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38363074

RESUMO

Human African trypanosomiasis (HAT), a neglected tropical disease caused by Trypanosoma brucei gambiense (Tbg) or Trypanosoma brucei rhodesiense (Tbr), remains a significant public health concern with over 55 million people at risk of infection. Current treatments for HAT face the challenges of poor efficacy, drug resistance, and toxicity. This study presents the synthesis and evaluation of chloronitrobenzamides (CNBs) against Trypanosoma species, identifying previously reported compound 52 as a potent and selective orally bioavailable antitrypanosomal agent. 52 was well tolerated in vivo and demonstrated favorable oral pharmacokinetics, maintaining plasma concentrations surpassing the cellular EC50 for over 24 h and achieving peak brain concentrations exceeding 7 µM in rodents after single oral administration (50 mg/kg). Treatment with 52 significantly extended the lifespan of mice infected with Trypanosoma congolense and T. brucei rhodesiense. These results demonstrate that 52 is a strong antitrypanosomal lead with potential for developing treatments for both human and animal African trypanosomiasis.


Assuntos
Tripanossomicidas , Trypanosoma brucei brucei , Tripanossomíase Africana , Humanos , Animais , Camundongos , Tripanossomíase Africana/tratamento farmacológico , Trypanosoma brucei rhodesiense , Trypanosoma brucei gambiense , Tripanossomicidas/toxicidade , Tripanossomicidas/uso terapêutico
7.
PLoS Negl Trop Dis ; 18(2): e0011956, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38359089

RESUMO

BACKGROUND: Chagas disease is caused by the protozoan parasite Trypanosoma cruzi and leads to ~10,000 deaths each year. Nifurtimox and benznidazole are the only two drugs available but have significant adverse effects and limited efficacy. New chemotherapeutic agents are urgently required. Here we identified inhibitors of the acidic M17 leucyl-aminopeptidase from T. cruzi (LAPTc) that show promise as novel starting points for Chagas disease drug discovery. METHODOLOGY/PRINCIPAL FINDINGS: A RapidFire-MS screen with a protease-focused compound library identified novel LAPTc inhibitors. Twenty-eight hits were progressed to the dose-response studies, from which 12 molecules inhibited LAPTc with IC50 < 34 µM. Of these, compound 4 was the most potent hit and mode of inhibition studies indicate that compound 4 is a competitive LAPTc inhibitor, with Ki 0.27 µM. Compound 4 is selective with respect to human LAP3, showing a selectivity index of >500. Compound 4 exhibited sub-micromolar activity against intracellular T. cruzi amastigotes, and while the selectivity-window against the host cells was narrow, no toxicity was observed for un-infected HepG2 cells. In silico modelling of the LAPTc-compound 4 interaction is consistent with the competitive mode of inhibition. Molecular dynamics simulations reproduce the experimental binding strength (-8.95 kcal/mol), and indicate a binding mode based mainly on hydrophobic interactions with active site residues without metal cation coordination. CONCLUSIONS/SIGNIFICANCE: Our data indicates that these new LAPTc inhibitors should be considered for further development as antiparasitic agents for the treatment of Chagas disease.


Assuntos
Doença de Chagas , Tripanossomicidas , Trypanosoma cruzi , Humanos , Leucil Aminopeptidase/química , Leucil Aminopeptidase/farmacologia , Leucil Aminopeptidase/uso terapêutico , Doença de Chagas/tratamento farmacológico , Descoberta de Drogas , Antiparasitários/uso terapêutico , Tripanossomicidas/uso terapêutico
8.
J Med Chem ; 67(4): 2584-2601, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38305199

RESUMO

A series of 28 compounds, 3-nitro-1H-1,2,4-triazole, were synthesized by click-chemistry with diverse substitution patterns using medicinal chemistry approaches, such as bioisosterism, Craig-plot, and the Topliss set with excellent yields. Overall, the analogs demonstrated relevant in vitro antitrypanosomatid activity. Analog 15g (R1 = 4-OCF3-Ph, IC50 = 0.09 µM, SI = >555.5) exhibited an outstanding antichagasic activity (Trypanosoma cruzi, Tulahuen LacZ strain) 68-fold more active than benznidazole (BZN, IC50 = 6.15 µM, SI = >8.13) with relevant selectivity index, and suitable LipE = 5.31. 15g was considered an appropriate substrate for the type I nitro reductases (TcNTR I), contributing to a likely potential mechanism of action for antichagasic activity. Finally, 15g showed nonmutagenic potential against Salmonella typhimurium strains (TA98, TA100, and TA102). Therefore, 3-nitro-1H-1,2,4-triazole 15g is a promising antitrypanosomatid candidate for in vivo studies.


Assuntos
Doença de Chagas , Leishmaniose , Tripanossomicidas , Trypanosoma cruzi , Humanos , Relação Estrutura-Atividade , Doença de Chagas/tratamento farmacológico , Triazóis/química
9.
J Med Chem ; 67(4): 2849-2863, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38330051

RESUMO

Human African trypanosomiasis (HAT) still faces few therapeutic options and emerging drug resistance, stressing an urgency for novel antitrypanosomal drug discovery. Here, we describe lead optimization efforts aiming at improving antitrypanosomal efficacy and better physicochemical properties based on our previously reported optimized hit NPD-2975 (pIC50 7.2). Systematic modification of the 5-phenylpyrazolopyrimidinone NPD-2975 led to the discovery of a R4-substituted analogue 31c (NPD-3519), showing higher in vitro potency (pIC50 7.8) against Trypanosoma brucei and significantly better metabolic stability. Further, in vivo pharmacokinetic evaluation of 31c and experiments in an acute T. brucei mouse model confirmed improved oral bioavailability and antitrypanosomal efficacy at 50 mg/kg with no apparent toxicity. With good physicochemical properties, low toxicity, improved pharmacokinetic features, and in vivo efficacy, 31c may serve as a promising candidate for future drug development for HAT.


Assuntos
Antiprotozoários , Tripanossomicidas , Trypanosoma brucei brucei , Tripanossomíase Africana , Animais , Camundongos , Humanos , Tripanossomicidas/farmacologia , Tripanossomicidas/uso terapêutico , Tripanossomíase Africana/tratamento farmacológico , Antiprotozoários/uso terapêutico , Desenvolvimento de Medicamentos
10.
PLoS Negl Trop Dis ; 18(1): e0011895, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38252673

RESUMO

BACKGROUND: In regions with controlled vector transmission of T. cruzi, congenital transmission is the most frequent route of infection. Treatment with benznidazole (BZ) or nifurtimox (NF) for 60 days in girls and women of childbearing age showed to be effective in preventing mother to child transmission of this disease. Reports on short-course treatment (≤30 days) are scarce. METHODS: Retrospective cohort study. Offspring of women with Chagas disease who received short-course treatment (≤30 days) with BZ or NF, attended between 2003 and 2022, were evaluated. Parasitemia (microhaematocrit and/or PCR) was performed at <8 months of age, and serology (ELISA and IHA) at ≥8 months to rule out congenital infection. RESULTS: A total of 27 women receiving ≤30 days of treatment and their children were included in this study. NF was prescribed in 17/27 (63%) women, and BZ in 10/27 (37%). The mean duration of treatment was 29.2 days. None of the women experienced serious adverse events during treatment, and no laboratory abnormalities were observed. Forty infants born to these 27 treated women were included. All newborns were full term, with appropriate weight for their gestational age. No perinatal infectious diseases or complications were observed. DISCUSSION: Several studies have shown that treatment of infected girls and women of childbearing age for 60 days is an effective practice to prevent transplacental transmission of T. cruzi. Our study demonstrated that short-duration treatment (≤30 days) is effective and beneficial in preventing transplacental transmission of Chagas disease.


Assuntos
Doença de Chagas , Nitroimidazóis , Tripanossomicidas , Trypanosoma cruzi , Lactente , Criança , Recém-Nascido , Humanos , Feminino , Masculino , Estudos Retrospectivos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Doença de Chagas/tratamento farmacológico , Doença de Chagas/prevenção & controle , Nifurtimox/uso terapêutico , Nitroimidazóis/uso terapêutico , Tripanossomicidas/uso terapêutico
11.
Future Med Chem ; 16(3): 253-269, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38193294

RESUMO

Background: Chagas disease is caused by the parasite Trypanosoma cruzi, and the lack of effective and safe treatments makes identifying new classes of compounds with anti-T. cruzi activity of paramount importance. Methods: Hit-to-lead exploration of a metabolically stable N-imidazoylpiperazine was performed. Results: Compound 2, a piperazine derivative active against T. cruzi, was selected to perform the hit-to-lead exploration, which involved the design, synthesis and biological evaluation of 39 new derivatives. Conclusion: Compounds 6e and 10a were identified as optimized compounds with low micromolar in vitro activity, low cytotoxicity and suitable preliminary absorption, distribution, metabolism and excretion and physicochemical properties. Both compounds reduced parasitemia in mouse models of Chagas disease, providing a promising opportunity for further exploration of new antichagasic compounds.


Assuntos
Doença de Chagas , Tripanossomicidas , Trypanosoma cruzi , Animais , Camundongos , Tripanossomicidas/farmacologia , Tripanossomicidas/química , Doença de Chagas/tratamento farmacológico , Doença de Chagas/parasitologia , Relação Estrutura-Atividade , Parasitemia/tratamento farmacológico
12.
Future Med Chem ; 16(3): 221-238, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38269432

RESUMO

Aim: To synthesize novel more potent trypanocidal and leishmanicidal agents. Methods: Hantzsch's synthetic strategy was used to synthesize 1,3-thiazole-4-carboxylates and their N-benzylated derivatives. Results: 28 new thiazole-carboxylates and their N-benzylated derivatives were established to test their trypanocidal and leishmanicidal activities. From both series, compounds 3b, 4f, 4g, 4j and 4n exhibited a better or comparable trypanocidal profile to benznidazole. Among all tested compounds, 4n was found to be the most potent and was better than benznidazole. Conclusion: Further variation of substituents around 1,3-thiazole-4-carboxylates and or hydrazinyl moiety may assist in establishing better and more potent trypanocidal and leishmanicidal agents.


Chagas disease and leishmaniasis are neglected tropical diseases. Herein, 28 1,3-thiazoles have been synthesized from thiosemicarbazones in a rapid, efficient and cost-effective manner. In vitro assays were performed against intracellular amastigotes of Trypanosoma cruzi (T. cruzi) and promastigotes and intracellular amastigote forms of Leishmania infantum (L. infantum) and Leishmania amazonensis (L. amazonensis). Some of the 1,3-thiazole-4-carboxylates inhibited the amastigote form of T. cruzi without affecting macrophage viability, compound 4n being the most potent and better than benznidazole. Our synthesized compounds exhibited promising activity against T. cruzi, thus broadening options for scaffold and lead compound optimization. Concerning the leishmanicidal activity, compound 4g was the best prototype in terms of potency and selectivity. Compounds 4g and 3m showed moderate selectivity and potency against intracellular amastigotes of L. amazonensis and L. infantum, respectively.


Assuntos
Nitroimidazóis , Tripanossomicidas , Trypanosoma cruzi , Tiazóis/farmacologia , Ésteres/farmacologia , Tripanossomicidas/farmacologia
13.
BMC Vet Res ; 20(1): 32, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38279149

RESUMO

BACKGROUND: Animal trypanosomiasis is a major livestock problem due to its socioeconomic impacts in tropical countries. Currently used trypanocides are toxic, expensive, and the parasites have developed resistance to the existing drugs, which calls for an urgent need of new effective and safe chemotherapeutic agents from alternative sources such as medicinal plants. In Ethiopian traditional medicine fresh leaves of Ranunculus multifidus Forsk, are used for the treatment of animal trypanosomiasis. The present study aimed to evaluate the antitrypanosomal activity of the fresh leaves of R. multifidus and its major compound anemonin against Trypanosoma congolense field isolate. METHODS: Fresh leaves of R. multifidus were extracted by maceration with 80% methanol and hydro-distillation to obtain the corresponding extracts. Anemonin was isolated from the hydro-distilled extract by preparative TLC. For the in vitro assay, 0.1, 0.4, 2 and 4 mg/ml of the test substances were incubated with parasites and cessation or drop in motility of the parasites was monitored for a total duration of 1 h. In the in vivo assay, the test substances were administered intraperitoneally daily for 7 days to mice infected with Trypanosoma congolense. Diminazene aceturate and 1% dimethylsulfoxide (DMSO) were used as positive and negative controls, respectively. RESULTS: Both extracts showed antitrypanosomal activity although the hydro-distilled extract demonstrated superior activity compared to the hydroalcoholic extract. At a concentration of 4 mg/ml, the hydro-distilled extract drastically reduced motility of trypanosomes within 20 min. Similarly, anemonin at the same concentration completely immobilized trypanosomes within 5 min of incubation, while diminazene aceturate (28.00 mg/kg/day) immobilized the parasites within 10 min. In the in vivo antitrypanosomal assay, anemonin eliminates parasites at all the tested doses (8.75, 17.00 and 35.00 mg/kg/day) and prevented relapse, while in diminazene aceturate-treated mice the parasites reappeared on days 12 to 14. CONCLUSIONS: The current study demonstrated that the fresh leaves of R. multifidus possess genuine antitrypanosomal activity supporting the use of the plant for the treatment of animal trypanosomiasis in traditional medicine. Furthermore, anemonin appears to be responsible for the activity suggesting its potential as a scaffold for the development of safe and cost effective antitrypanosomal agent.


Assuntos
Furanos , Ranunculus , Tripanossomicidas , Tripanossomíase Africana , Animais , Camundongos , Diminazena/farmacologia , Diminazena/uso terapêutico , Músculos Paraespinais , Extratos Vegetais/uso terapêutico , Tripanossomicidas/farmacologia , Tripanossomicidas/uso terapêutico , Trypanosoma congolense , Tripanossomíase Africana/tratamento farmacológico , Tripanossomíase Africana/veterinária
14.
ChemMedChem ; 19(8): e202300656, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38277231

RESUMO

Studies have shown that depending on the substitution pattern, microtubule (MT)-targeting 1,2,4-triazolo[1,5-a]pyrimidines (TPDs) can produce different cellular responses in mammalian cells that may be due to these compounds interacting with distinct binding sites within the MT structure. Selected TPDs are also potently bioactive against the causative agent of human African trypanosomiasis, Trypanosoma brucei, both in vitro and in vivo. So far, however, there has been no direct evidence of tubulin engagement by these TPDs in T. brucei. Therefore, to enable further investigation of anti-trypanosomal TPDs, a TPD derivative amenable to photoaffinity labeling (PAL) was designed, synthesized, and evaluated in PAL experiments using HEK293 cells and T. brucei. The data arising confirmed specific labeling of T. brucei tubulin. In addition, proteomic data revealed differences in the labeling profiles of tubulin between HEK293 and T. brucei, suggesting structural differences between the TPD binding site(s) in mammalian and trypanosomal tubulin.


Assuntos
Tripanossomicidas , Trypanosoma brucei brucei , Tripanossomíase Africana , Animais , Humanos , Tubulina (Proteína)/metabolismo , Células HEK293 , Proteômica , Tripanossomíase Africana/tratamento farmacológico , Trypanosoma brucei brucei/metabolismo , Pirimidinas/química , Tripanossomicidas/química , Mamíferos/metabolismo
15.
Nat Prod Res ; 38(4): 690-695, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-36938813

RESUMO

Chagas disease is an infection caused by the protozoan Trypanosoma cruzi, affecting 6-8 million people worldwide. Only two drugs are available for its treatment, having a limited efficacy and adverse side-effects. Estafietin is a sesquiterpene lactone isolated from Stevia alpina with in vitro activity against T. cruzi and low cytotoxicity against mammalian cells. The aim of this work was to predict the toxicologic profile of estafietin by in silico methods and assess its in vivo activity on a murine model of Chagas disease. Estafietin showed low toxicity according to pkCSM web tool and passed the PAINS filter from PAINS-remover web server. The treatment of infected mice with 1 mg/Kg/day of estafietin for five consecutive days administrated by intraperitoneal route significatively decreased parasitemia levels and reduced inflammatory infiltrates and myocyte damage on muscle tissue. These results suggest that estafietin had effect both on acute and chronic stages of the infection.


Assuntos
Doença de Chagas , Stevia , Tripanossomicidas , Trypanosoma cruzi , Humanos , Camundongos , Animais , Tripanossomicidas/farmacologia , Tripanossomicidas/uso terapêutico , Doença de Chagas/tratamento farmacológico , Sesquiterpenos de Guaiano/farmacologia , Parasitemia/tratamento farmacológico , Lactonas/farmacologia , Lactonas/uso terapêutico , Mamíferos
16.
Chem Biol Drug Des ; 103(1): e14400, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37994272

RESUMO

A library of imidazo[1,2-a]pyridine-appended chalcones were synthesized and characterized using 1 H NMR, 13 C NMR and HRMS. The synthesized analogues were screened for their antikinetoplastid activity against Trypanosoma cruzi, Trypanosoma brucei brucei, Trypanosoma brucei rhodesiense and Leishmania infantum. The analogues were also tested for their cytotoxicity activity against human lung fibroblasts and primary mouse macrophages. Among all screened derivatives, 7f was found to be the most active against T. cruzi and T. b. brucei exhibiting IC50 values of 8.5 and 1.35 µM, respectively. Against T. b. rhodesiense, 7e was found to be the most active with an IC50 value of 1.13 µM. All synthesized active analogues were found to be non-cytotoxic against MRC-5 and PMM with selectivity indices of up to more than 50.


Assuntos
Antiprotozoários , Doença de Chagas , Chalcona , Chalconas , Tripanossomicidas , Trypanosoma brucei brucei , Trypanosoma cruzi , Camundongos , Animais , Humanos , Antiprotozoários/química , Chalconas/farmacologia , Chalconas/uso terapêutico , Doença de Chagas/tratamento farmacológico , Piridinas/uso terapêutico , Tripanossomicidas/química
17.
Future Med Chem ; 16(1): 11-26, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38084595

RESUMO

Aim: Our objective was to investigate the trypanocidal effect of the chalcone (2E,4E)-1-(2-hydroxy-3,4,6-trimethoxyphenyl)-5-phenylpenta-2,4-dien-1-one (CPNC). Material & methods: Cytotoxicity toward LLC-MK2 host cells was assessed by MTT assay, and the effect on Trypanosoma cruzi life forms (epimastigotes, trypomastigotes and amastigotes) was evaluated by counting. Flow cytometry analysis was performed to evaluate the possible mechanisms of action. Finally, molecular docking simulations were performed to evaluate interactions between CPNC and T. cruzi enzymes. Results: CPNC showed activity against epimastigote, trypomastigote and amastigote life forms, induced membrane damage, increased cytoplasmic reactive oxygen species and mitochondrial dysfunction on T. cruzi. Regarding molecular docking, CPNC interacted with both trypanothione reductase and TcCr enzymes. Conclusion: CPNC presented a trypanocidal effect, and its effect is related to oxidative stress, mitochondrial impairment and necrosis.


Assuntos
Doença de Chagas , Chalconas , Tripanossomicidas , Trypanosoma cruzi , Humanos , Chalconas/farmacologia , Simulação de Acoplamento Molecular , Doença de Chagas/tratamento farmacológico , Espécies Reativas de Oxigênio , Tripanossomicidas/farmacologia
18.
Eur J Med Chem ; 263: 115954, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37984297

RESUMO

Human African Trypanosomiasis (HAT), caused by Trypanosoma brucei gambiense and rhodesiense, is a parasitic disease endemic to sub-Saharan Africa. Untreated cases of HAT can be severely debilitating and fatal. Although the number of reported cases has decreased progressively over the last decade, the number of effective and easily administered medications is very limited. In this work, we report the antitrypanosomal activity of a series of potent compounds. A subset of molecules in the series are highly selective for trypanosomes and are metabolically stable. One of the compounds, (E)-N-(4-(methylamino)-4-oxobut-2-en-1-yl)-5-nitrothiophene-2-carboxamide (10), selectively inhibited the growth of T. b. brucei, T. b. gambiense and T. b. rhodesiense, have excellent oral bioavailability and was effective in treating acute infection of HAT in mouse models. Based on its excellent bioavailability, compound 10 and its analogs are candidates for lead optimization and pre-clinical investigations.


Assuntos
Tripanossomicidas , Trypanosoma brucei brucei , Tripanossomíase Africana , Animais , Camundongos , Humanos , Trypanosoma brucei rhodesiense , Tripanossomicidas/farmacologia , Tripanossomicidas/uso terapêutico , Tripanossomíase Africana/tratamento farmacológico , Tripanossomíase Africana/parasitologia , Trypanosoma brucei gambiense
19.
Sci Transl Med ; 15(726): eadg8105, 2023 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-38091410

RESUMO

Chagas disease, caused by the protozoan parasite Trypanosoma cruzi, affects millions of people in the Americas and across the world, leading to considerable morbidity and mortality. Current treatment options, benznidazole (BNZ) and nifurtimox, offer limited efficacy and often lead to adverse side effects because of long treatment durations. Better treatment options are therefore urgently required. Here, we describe a pyrrolopyrimidine series, identified through phenotypic screening, that offers an opportunity to improve on current treatments. In vitro cell-based washout assays demonstrate that compounds in the series are incapable of killing all parasites; however, combining these pyrrolopyrimidines with a subefficacious dose of BNZ can clear all parasites in vitro after 5 days. These findings were replicated in a clinically predictive in vivo model of chronic Chagas disease, where 5 days of treatment with the combination was sufficient to prevent parasite relapse. Comprehensive mechanism of action studies, supported by ligand-structure modeling, show that compounds from this pyrrolopyrimidine series inhibit the Qi active site of T. cruzi cytochrome b, part of the cytochrome bc1 complex of the electron transport chain. Knowledge of the molecular target enabled a cascade of assays to be assembled to evaluate selectivity over the human cytochrome b homolog. As a result, a highly selective and efficacious lead compound was identified. The combination of our lead compound with BNZ rapidly clears T. cruzi parasites, both in vitro and in vivo, and shows great potential to overcome key issues associated with currently available treatments.


Assuntos
Doença de Chagas , Parasitos , Tripanossomicidas , Trypanosoma cruzi , Animais , Humanos , Citocromos b , Tripanossomicidas/efeitos adversos , Doença de Chagas/tratamento farmacológico , Doença de Chagas/induzido quimicamente , Doença de Chagas/parasitologia
20.
Molecules ; 28(23)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38067542

RESUMO

Chagas disease (CD) is a worldwide public health problem, and the drugs available for its treatment have severe limitations. Red propolis is a natural extract known for its high content of phenolic compounds and for having activity against T. cruzi. The aim of this study was to investigate the trypanocidal potential of red propolis to isolate, identify, and indicate the mode of action of the bioactive compounds. The results revealed that the total phenolic content was 15.4 mg GAE/g, and flavonoids were 7.2 mg QE/g. The extract was fractionated through liquid-liquid partitioning, and the trypanocidal potential of the samples was evaluated using the epimastigote forms of the Y strain of T. cruzi. In this process, one compound was characterized by MS, 1H, and 13C NMR and identified as vestitol. Cytotoxicity was evaluated employing MRC-5 fibroblasts and H9C2 cardiomyocytes, showing cytotoxic concentrations above 15.62 µg/mL and 31.25 µg/mL, respectively. In silico analyses were applied, and the data suggested that the substance had a membrane-permeation-enhancing effect, which was confirmed through an in vitro assay. Finally, a molecular docking analysis revealed a higher affinity of vestitol with farnesyl diphosphate synthase (FPPS). The identified isoflavan appears to be a promising lead compound for further development to treat Chagas disease.


Assuntos
Doença de Chagas , Própole , Tripanossomicidas , Trypanosoma cruzi , Humanos , Própole/química , Simulação de Acoplamento Molecular , Doença de Chagas/tratamento farmacológico , Flavonoides/química , Extratos Vegetais/farmacologia , Tripanossomicidas/química
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