In Vitro and In Vivo Studies of the Trypanocidal Activity of Four Terpenoid Derivatives against Trypanosoma cruzi

ABSTRACT Chagas' disease is a serious public health problem in Latin America, and no treatment is available for the prevalent chronic stage. Its causative agent, Trypanosoma cruzi, requires specific endogenous sterols for survival, and we have recently demonstrated that squalene synthase (SQS) is a promising target for antiparasitic chemotherapy. E5700 and ER-119884 are quinuclidine-based inhibitors of mammalian SQS that are currently in development as cholesterol- and triglyceride-lowering agents in humans. These compounds were found to be potent noncompetitive or mixed-type inhibitors of T. cruzi SQS with K i values in the low nanomolar to subnanomolar range in the absence or presence of 20 μM inorganic pyrophosphate. The antiproliferative 50% inhibitory concentrations of the compounds against extracellular epimastigotes and intracellular amastigotes were ca. 10 nM and 0.4 to 1.6 nM, respectively, with no effects on host cells. When treated with these compounds at the MIC, all of the parasite's sterols disappeared from the parasite cells. In vivo studies indicated that E5700 was able to provide full protection against death and completely arrested the development of parasitemia when given at a concentration of 50 mg/kg of body weight/day for 30 days, while ER-119884 provided only partial protection. This is the first report of an orally active SQS inhibitor that is capable of providing complete protection against fulminant, acute Chagas' disease.

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Activity profile of two 5-nitroindazole derivatives over the moderately drug-resistant Trypanosoma cruzi Y strain (DTU TcII): in vitro and in vivo studies

Parasitology ◽

10.1017/s0031182020000955 ◽

2020 ◽

Vol 147 (11) ◽

pp. 1216-1228

Author(s):

Cristina Fonseca-Berzal ◽

Cristiane França da Silva ◽

Denise da Gama Jaen Batista ◽

Gabriel Melo de Oliveira ◽

José Cumella ◽

...

Keyword(s):

Trypanosoma Cruzi ◽

Positive Impact ◽

Cardiac Cells ◽

In Vivo Studies ◽

Drug Resistant ◽

Activity Profile ◽

Reference Drug ◽

Novel Drugs

AbstractIn previous studies, we have identified several families of 5-nitroindazole derivatives as promising antichagasic prototypes. Among them, 1-(2-aminoethyl)-2-benzyl-5-nitro-1,2-dihydro-3H-indazol-3-one, (hydrochloride) and 1-(2-acetoxyethyl)-2-benzyl-5-nitro-1,2-dihydro-3H-indazol-3-one (compounds 16 and 24, respectively) have recently shown outstanding activity in vitro over the drug-sensitive Trypanosoma cruzi CL strain (DTU TcVI). Here, we explored the activity of these derivatives against the moderately drug-resistant Y strain (DTU TcII), in vitro and in vivo. The outcomes confirmed their activity over replicative forms, showing IC50 values of 0.49 (16) and 5.75 μm (24) towards epimastigotes, 0.41 (16) and 1.17 μm (24) against intracellular amastigotes. These results, supported by the lack of toxicity on cardiac cells, led to better selectivities than benznidazole (BZ). Otherwise, they were not as active as BZ in vitro against the non-replicative form of the parasite, i.e. bloodstream trypomastigotes. In vivo, acute toxicity assays revealed the absence of toxic events when administered to mice. Moreover, different therapeutic schemes pointed to their capability for decreasing the parasitaemia of T. cruzi Y acute infected mice, reaching up to 60% of reduction at the peak day as monotherapy (16), 79.24 and 91.11% when 16 and 24 were co-administered with BZ. These combined therapies had also a positive impact over the mortality, yielding survivals of 83.33 and 66.67%, respectively, while untreated animals reached a cumulative mortality of 100%. These findings confirm the 5-nitroindazole scaffold as a putative prototype for developing novel drugs potentially applicable to the treatment of Chagas disease and introduce their suitability to act in combination with the reference drug.

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Repositioning FDA Drugs as Potential Cruzain Inhibitors from Trypanosoma cruzi: Virtual Screening, In Vitro and In Vivo Studies

Molecules ◽

10.3390/molecules22061015 ◽

2017 ◽

Vol 22 (6) ◽

pp. 1015 ◽

Cited By ~ 14

Author(s):

Isidro Palos ◽

Edgar E. Lara-Ramirez ◽

Julio Cesar Lopez-Cedillo ◽

Carlos Garcia-Perez ◽

Muhammad Kashif ◽

...

Keyword(s):

Virtual Screening ◽

Trypanosoma Cruzi ◽

In Vivo Studies ◽

Screening In Vitro ◽

Cruzain Inhibitors

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Promising Efficacy of Benznidazole Nanoparticles in Acute Trypanosoma cruzi Murine Model: In-Vitro and In-Vivo Studies

American Journal of Tropical Medicine and Hygiene ◽

10.4269/ajtmh.15-0889 ◽

2016 ◽

Vol 95 (2) ◽

pp. 388-393 ◽

Cited By ~ 15

Author(s):

María L. Scalise ◽

Mónica I. Esteva ◽

Marcela S. Rial ◽

Laura E. Fichera ◽

Eva C. Arrúa ◽

...

Keyword(s):

Trypanosoma Cruzi ◽

Murine Model ◽

In Vivo Studies

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Screening of Potential anti-Trypanosoma cruzi Candidates: In Vitro and In Vivo Studies

The Open Medicinal Chemistry Journal ◽

10.2174/1874104501105010021 ◽

2011 ◽

Vol 5 ◽

pp. 21-30 ◽

Cited By ~ 48

Author(s):

Maria de Nazaré C Soeiro ◽

Solange Lisboa de Castro

Keyword(s):

Trypanosoma Cruzi ◽

In Vivo Studies

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In Vitro and In Vivo Studies of the Trypanocidal Activity of a Diarylthiophene Diamidine against Trypanosoma cruzi

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00038-08 ◽

2008 ◽

Vol 52 (9) ◽

pp. 3307-3314 ◽

Cited By ~ 43

Author(s):

Cristiane França da Silva ◽

Marcos Meuser Batista ◽

Denise da Gama Jaen Batista ◽

Elen Mello de Souza ◽

Patrícia Bernardino da Silva ◽

...

Keyword(s):

Trypanosoma Cruzi ◽

Chagas Disease ◽

In Vivo Studies ◽

Groove Binding ◽

Dna Minor Groove ◽

Drug Concentrations ◽

Mammalian Infection ◽

Related Compounds

ABSTRACT Aromatic diamidines are DNA minor groove-binding ligands that display excellent antimicrobial activity against fungi, bacteria, and protozoa. Due to the currently unsatisfactory chemotherapy for Chagas’ disease and in view of our previous reports regarding the effect of diamidines and analogues against both in vitro and in vivo Trypanosoma cruzi infection, this study evaluated the effects of a diarylthiophene diamidine (DB1362) against both amastigotes and bloodstream trypomastigotes of T. cruzi, the etiological agent of Chagas’ disease. The data show the potent in vitro activity of DB1362 against both parasite forms that are relevant for mammalian infection at doses which do not exhibit cytotoxicity. Ultrastructural analysis and flow cytometry studies show striking alterations in the nuclei and mitochondria of the bloodstream parasites. In vivo studies were performed at two different drug concentrations (25 and 50 mg/kg/day) using a 2-day or a 10-day regimen. The best results were obtained when acutely infected mice were treated with two doses at the lower concentration, resulting in 100% survival, compared to the infected and untreated mice. Although it did not display higher efficacy than benznidazole, DB1362 reduced both cardiac parasitism and inflammation, and in addition, it protected against the cardiac alterations (determined by measurements) common in T. cruzi infection. These results support further investigation of diamidines and related compounds as potential agents against Chagas’ disease.

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Trypanosoma cruzi: in vitro induction of macrophage microbicidal activity.

Journal of Experimental Medicine ◽

10.1084/jem.148.1.288 ◽

1978 ◽

Vol 148 (1) ◽

pp. 288-300 ◽

Cited By ~ 94

Author(s):

N Nogueira ◽

Z A Cohn

Keyword(s):

Trypanosoma Cruzi ◽

Spleen Cell ◽

Peritoneal Macrophages ◽

Complete Disappearance ◽

Microbicidal Activity ◽

Trypanocidal Activity ◽

Intracellular Parasites ◽

Normal Spleen

Normal, resident and inflammatory mouse peritoneal macrophages can be induced to display microbicidal activity against trypomastigotes of Trypanosoma cruzi by exposure to products from antigen-pulsed, sensitized spleen cell populations. Optimal macrophage microbicidal activity was achieved by constant exposure and daily renewal of the spleen cell factors. Macrophages obtained after an intraperitoneal injection of mild inflammatory agents were rapidly induced, displaying trypanocidal activity 24 h after exposure to the active spleen cell factor(s), and by 48 h, parasites were no longer observed. Resident peritoneal macrophages required 24 h longer for activation. Removal of the factor(s) before achieving complete disappearance of intracellular parasites led to resumed growth of the surviving organisms. The spleen cell factor(s) is effective when added either before or after exposure of the macrophages to trypomastigotes, and does not itself alter parasite viability. Dilution of the factor(s) up to 1:16 still results in significant trypanocidal activity. In vivo activated cells, obtained after a specific secondary challenge of animals infected with T. cruzi or Bacille Calmette-Guérin, lose their trypanocidal activity under in vitro conditions. This loss of activity can be prevented or restored by the addition of the active spleen cell factor(s). Induction of trypanocidal activity is also obtained with products from Concanavalin A- or lipopolysaccharide-stimulated normal spleen cells.

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IN VITRO and IN VIVO TRYPANOCIDAL ACTIVITY OF A BENZOFUROXAN DERIVATIVE AGAINST Trypanosoma cruzi

Experimental Parasitology ◽

10.1016/j.exppara.2021.108125 ◽

2021 ◽

pp. 108125

Author(s):

Letícia dos Santos Petry ◽

João Cândido Pillar Mayer ◽

Marjorie de Giacommeti ◽

Dionatan Teixeira de Oliveira ◽

Litiérria Razia Garzon ◽

...

Keyword(s):

Trypanosoma Cruzi ◽

Trypanocidal Activity

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Activation of macrophages in vivo and in vitro. Correlation between hydrogen peroxide release and killing of Trypanosoma cruzi.

Journal of Experimental Medicine ◽

10.1084/jem.149.5.1056 ◽

1979 ◽

Vol 149 (5) ◽

pp. 1056-1068 ◽

Cited By ~ 183

Author(s):

C Nathan ◽

N Nogueira ◽

C Juangbhanich ◽

J Ellis ◽

Z Cohn

Keyword(s):

Trypanosoma Cruzi ◽

Peritoneal Macrophages ◽

Trypanocidal Activity ◽

Dose Dependent Fashion ◽

Hydrogen Peroxide Release ◽

Inflammatory Macrophages ◽

Dose Dependent ◽

Mouse Peritoneal Macrophages

As reported previously, mouse peritoneal macrophages could be activated to kill intracellular trypomastigotes of Trypanosoma cruzi, the agent of Chagas' disease, in either of two ways: by immunizing and boosting the mice (3), or by culturing resident or inflammatory macrophages in spleen cell factor(s) (SCF) in vitro (2). Macrophages activated in vivo became less trypanocidal with time in culture, and cells activated in vitro lost trypanocidal capacity when CSF was removed (2). In the present study, the ability of macrophages to release H2O2 in response to phorbol myristate acetate (PMA) could be induced in vivo and in vitro, and reversed in vitro, in a manner correlating closely with changes in trypanocidal activity. Macrophages could be activated in vitro with SCF in a time-dependent and dose-dependent fashion, so that they released as much H2O2 as macrophages activated in vivo. The sensitivity of epimastigotes and trypomastigotes to enzymatically generated H2O2 suggested that the generation of H2O2 by activated macrophages could be plausible explanation for their trypanocidal activity. Of the biochemical correlates of macrophage activation reported to date, increased ability to release H2O2 seems most closely allied to enhanced capacity to kill an intracellular pathogen.

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