New Trypanosoma cruzi Trypanothione Reductase Inhibitors Identification using the Virtual Screening in Database of Nucleus Bioassay, Biosynthesis and Ecophysiology (NuBBE)

2019 ◽  
Vol 17 (2) ◽  
pp. 138-149
Author(s):  
Nelcí do Carmo Santos ◽  
Vinícius G. da Paixão ◽  
Samuel S. da Rocha Pita

Background: American trypanosomiasis, also known as Chagas disease, is caused by the protozoan Trypanosoma cruzi (T. cruzi) and affects approximately 10 to 12 million, primarily in Latin America. Since its discovery in 1909, there is no effective treatment for its chronic phase, with benzonidazole being the only anti-trypanosoma drug used in Brazil, despite the absence of conclusive evidence to prove its efficacy and safety. Thus, it is necessary to develop new drugs that are more effective and selective against Trypanosoma cruzi. Methods: The T. cruzi enzyme Trypanothione Reductase (TcTR) is a validated target for the discovery of new antiprotozoal compounds and we employed the Virtual Screening technique on the database of Nucleus of Bioassays, Biosynthesis and Ecophysiology (NuBBE), aiming to search for new chemical moieties against T. cruzi. From these we selected the 10 best ligand energies interactions and verified their interaction profile with the main TcTR sites through the AuPosSOM server (https://www.biomedicale.univ-paris5.fr/aupossom). Results and Conclusion: Finally, we analyzed some pharmacokinetics and toxicological information through the servers Aggregator Advisor (http://advisor.bkslab.org), Pred-hERG 4.0 (http://labmol.com.br/predherg) and pkCSM (http://biosig.unimelb.edu.au/pkcsm/prediction) which we expect will be useful in in vitro preclinical trials.</P>

2019 ◽  
Vol 20 (7) ◽  
pp. 1742 ◽  
Author(s):  
Verónica Herrera-Mayorga ◽  
Edgar Lara-Ramírez ◽  
Karla Chacón-Vargas ◽  
Charmina Aguirre-Alvarado ◽  
Lorena Rodríguez-Páez ◽  
...  

Chagas disease (CD), or American trypanosomiasis, causes more than 10,000 deaths per year in the Americas. Current medical therapy for CD has low efficacy in the chronic phase of the disease and serious adverse effects; therefore, it is necessary to search for new pharmacological treatments. In this work, the ZINC15 database was filtered using the N-acylhydrazone moiety and a subsequent structure-based virtual screening was performed using the cruzain enzyme of Trypanosoma cruzi to predict new potential cruzain inhibitors. After a rational selection process, four compounds, Z2 (ZINC9873043), Z3 (ZINC9870651), Z5 (ZINC9715287), and Z6 (ZINC9861447), were chosen to evaluate their in vitro trypanocidal activity and enzyme inhibition. Compound Z5 showed the best trypanocidal activity against epimatigote (IC50 = 36.26 ± 9.9 μM) and trypomastigote (IC50 = 166.21 ± 14.5 μM and 185.1 ± 8.5 μM on NINOA and INC-5 strains, respectively) forms of Trypanosoma cruzi. In addition, Z5 showed a better inhibitory effect on Trypanosoma cruzi proteases than S1 (STK552090, 8-chloro-N-(3-morpholinopropyl)-5H-pyrimido[5,4-b]-indol-4-amine), a known cruzain inhibitor. This study encourages the use of computational tools for the rational search for trypanocidal drugs.


2021 ◽  
Vol 18 (4) ◽  
pp. 398-418
Author(s):  
Vinícius Guimarães da Paixão ◽  
Samuel Silva da Rocha Pita

Background: Leishmania infantum causes the most lethal form of Leishmaniasis: Visceral leishmaniasis. Current therapy for this disease is related to the development of drug-resistant species and toxicity. Trypanothione Reductase (LiTR), a validated target for the drug discovery process, is involved with parasites' thiol-redox metabolism. Objective: In this study, through Virtual Screening employing two distinct Natural Products Brazilian databases, we aimed to identify novel inhibitor scaffolds against LiTR. Results: Thus, the “top 10” LiTR-ligand energies have been selected and their interaction profiles into LiTR sites through the AuPosSOM server have been verified. Finally, Pred-hERG, Aggregator Advisor, FAF-DRUGS, pkCSM and DataWarrior were employed and their results allowed us to evaluate, respectively, the cardiotoxicity, aggregation capacity, presence of false-positive compounds (PAINS) and their toxicities. Conclusion: Three molecules that overcame the in silico pharmacokinetic analysis and have a good interaction with LiTR, were chosen to use in vitro assays hoping that our computational results reported here would aid the development of new anti-leishmanial compounds.


2010 ◽  
Vol 54 (9) ◽  
pp. 3738-3745 ◽  
Author(s):  
Sharon King-Keller ◽  
Minyong Li ◽  
Alyssa Smith ◽  
Shilong Zheng ◽  
Gurpreet Kaur ◽  
...  

ABSTRACT Trypanosoma cruzi phosphodiesterase (PDE) C (TcrPDEC), a novel and rather unusual PDE in which, unlike all other class I PDEs, the catalytic domain is localized in the middle of the polypeptide chain, is able to hydrolyze cyclic GMP (cGMP), although it prefers cyclic AMP (cAMP), and has a FYVE-type domain in its N-terminal region (S. Kunz et al., FEBS J. 272:6412-6422, 2005). TcrPDEC shows homology to the mammalian PDE4 family members. PDE4 inhibitors are currently under development for the treatment of inflammatory diseases, such as asthma, chronic pulmonary diseases, and psoriasis, and for treating depression and serving as cognitive enhancers. We therefore tested a number of compounds originally synthesized as potential PDE4 inhibitors on T. cruzi amastigote growth, and we obtained several useful hits. We then conducted homology modeling of T. cruzi PDEC and identified other compounds as potential inhibitors through virtual screening. Testing of these compounds against amastigote growth and recombinant TcrPDEC activity resulted in several potent inhibitors. The most-potent inhibitors were found to increase the cellular concentration of cAMP. Preincubation of cells in the presence of one of these compounds stimulated volume recovery after hyposmotic stress, in agreement with their TcrPDEC inhibitory activity in vitro, providing chemical validation of this target. The compounds found could be useful tools in the study of osmoregulation in T. cruzi. In addition, their further optimization could result in the development of new drugs against Chagas' disease and other trypanosomiases.


2011 ◽  
Vol 2011 ◽  
pp. 1-13 ◽  
Author(s):  
Solange L. de Castro ◽  
Denise G. J. Batista ◽  
Marcos M. Batista ◽  
Wanderson Batista ◽  
Anissa Daliry ◽  
...  

Chagas disease (CD), caused by Trypanosoma cruzi, affects approximately eight million individuals in Latin America and is emerging in nonendemic areas due to the globalisation of immigration and nonvectorial transmission routes. Although CD represents an important public health problem, resulting in high morbidity and considerable mortality rates, few investments have been allocated towards developing novel anti-T. cruzi agents. The available therapy for CD is based on two nitro derivatives (benznidazole (Bz) and nifurtimox (Nf)) developed more than four decades ago. Both are far from ideal due to substantial secondary side effects, limited efficacy against different parasite isolates, long-term therapy, and their well-known poor activity in the late chronic phase. These drawbacks justify the urgent need to identify better drugs to treat chagasic patients. Although several classes of natural and synthetic compounds have been reported to act in vitro and in vivo on T. cruzi, since the introduction of Bz and Nf, only a few drugs, such as allopurinol and a few sterol inhibitors, have moved to clinical trials. This reflects, at least in part, the absence of well-established universal protocols to screen and compare drug activity. In addition, a large number of in vitro studies have been conducted using only epimastigotes and trypomastigotes instead of evaluating compounds' activities against intracellular amastigotes, which are the reproductive forms in the vertebrate host and are thus an important determinant in the selection and identification of effective compounds for further in vivo analysis. In addition, due to pharmacokinetics and absorption, distribution, metabolism, and excretion characteristics, several compounds that were promising in vitro have not been as effective as Nf or Bz in animal models of T. cruzi infection. In the last two decades, our team has collaborated with different medicinal chemistry groups to develop preclinical studies for CD and investigate the in vitro and in vivo efficacy, toxicity, selectivity, and parasite targets of different classes of natural and synthetic compounds. Some of these results will be briefly presented, focusing primarily on diamidines and related compounds and naphthoquinone derivatives that showed the most promising efficacy against T. cruzi.


Biomolecules ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1564
Author(s):  
Guilherme C. Lechuga ◽  
Paloma Napoleão-Pêgo ◽  
Carolina C. G. Bottino ◽  
Rosa T. Pinho ◽  
David W. Provance-Jr ◽  
...  

The increasing detection of infections of Trypanosoma cruzi, the etiological agent of Chagas disease, in non-endemic regions beyond Latin America has risen to be a major public health issue. With an impact in the millions of people, current treatments rely on antiquated drugs that produce severe side effects and are considered nearly ineffective for the chronic phase. The minimal progress in the development of new drugs highlights the need for advances in basic research on crucial biochemical pathways in T. cruzi to identify new targets. Here, we report on the T. cruzi presenilin-like transmembrane aspartyl enzyme, a protease of the aspartic class in a unique phylogenetic subgroup with T. vivax separate from protozoans. Computational analyses suggest it contains nine transmembrane domains and an active site with the characteristic PALP motif of the A22 family. Multiple linear B-cell epitopes were identified by SPOT-synthesis analysis with Chagasic patient sera. Two were chosen to generate rabbit antisera, whose signal was primarily localized to the flagellar pocket, intracellular vesicles, and endoplasmic reticulum in parasites by whole-cell immunofluorescence. The results suggest that the parasitic presenilin-like enzyme could have a role in the secretory pathway and serve as a target for the generation of new therapeutics specific to the T. cruzi.


Molecules ◽  
2017 ◽  
Vol 22 (6) ◽  
pp. 1015 ◽  
Author(s):  
Isidro Palos ◽  
Edgar E. Lara-Ramirez ◽  
Julio Cesar Lopez-Cedillo ◽  
Carlos Garcia-Perez ◽  
Muhammad Kashif ◽  
...  

2020 ◽  
Author(s):  
Edward A. Valera-Vera ◽  
Chantal Reigada ◽  
Melisa Sayé ◽  
Fabio A. Digirolamo ◽  
Mariana R. Miranda ◽  
...  

ABSTRACTTrypanosoma cruzi is the causative agent of Chagas disease, considered within the list of twenty neglected diseases according to the World Health Organization. There are only two therapeutic drugs for Chagas disease, both of them unsuitable for the chronic phase, therefore the development of new drugs is a priority.T. cruzi arginine kinase (TcAK) is a promising drug target since it is absent in humans and it is involved in cellular stress responses. In a previous study from our laboratory, possible TcAK inhibitors were identified through computer simulations, resulting in the best-scoring compounds cyanidin derivatives and capsaicin. Considering these results, in this work we evaluate the effect of capsaicin on TcAK activity and its trypanocidal effect. Although capsaicin produced a weak inhibition on the recombinant TcAK activity (IC50 ≈ 800 µM), it had a strong trypanocidal effect on epimastigotes and trypomastigotes (IC50 = 6.26 µM and 0.26 µM, respectively) being 20-fold more active on trypomastigotes than mammalian cells. Epimastigotes that overexpress TcAK were 37% more resistant to capsaicin than wild type parasites, suggesting that trypanocidal activity could be due, in part, to the enzyme inhibition. However, the difference between the concentrations at which the enzyme is inhibited and the parasite death is caused implies the presence of other targets. In this sense, the prohibitin-2 and calmodulin were identified as other possible capsaicin targets. Capsaicin is a strong and selective trypanocidal agent active in nanomolar concentrations, with an IC50 57-fold lower than benznidazole, the drug currently used for treating Chagas disease.


2019 ◽  
Vol 15 (3) ◽  
pp. 265-276 ◽  
Author(s):  
Mariela Bollini ◽  
Ana M. Bruno ◽  
María E. Niño ◽  
Juan J. Casal ◽  
Leandro D. Sasiambarrena ◽  
...  

Background: Chagas disease affects about 7 million people worldwide. Only two drugs are currently available for the treatment for this parasite disease, namely, benznidazol (Bzn) and nifurtimox (Nfx). Both drugs have limited curative power in the chronic phase of the disease. Therefore, continuous research is an urgent need so as to discover novel therapeutic alternatives. Objective: The development of safer and more efficient therapeutic anti-T. cruzi drugs continues to be a major goal in trypanocidal chemotherapy. Method: Synthesis, 2D-QSAR and drug-like physicochemical properties of a set of quinazolinone and quinazoline derivatives were studied as trypanocidal agents. All compounds were screened in vitro against Trypanosoma cruzi (Tulahuen strain, Tul 2 stock) epimastigotes and bloodstream trypomastigotes. Results: Out of 34 compounds synthesized and tested, six compounds (5a, 5b, 9b, 9h, 13f and 13p) displayed significant activity against both epimastigotes and tripomastigotes, without exerting toxicity on Vero cells. Conclusion: The antiprotozoal activity of these quinazolinone and quinazoline derivatives represents an interesting starting point for a medicinal chemistry program aiming at the development of novel chemotherapies for Chagas disease.


2012 ◽  
Vol 2012 ◽  
pp. 1-13 ◽  
Author(s):  
Santhosh K. Venkatesan ◽  
Vikash Kumar Dubey

Structure-based virtual screening of NCI Diversity set II compounds was performed to indentify novel inhibitor scaffolds of trypanothione reductase (TR) fromLeishmania infantum. The top 50 ranked hits were clustered using the AuPoSOM tool. Majority of the top-ranked compounds were Tricyclic. Clustering of hits yielded four major clusters each comprising varying number of subclusters differing in their mode of binding and orientation in the active site. Moreover, for the first time, we report selected alkaloids and dibenzothiazepines as inhibitors ofLeishmania infantumTR. The mode of binding observed among the clusters also potentiates the probablein vitroinhibition kinetics and aids in defining key interaction which might contribute to the inhibition of enzymatic reduction of T[S] 2. The method provides scope for automation and integration into the virtual screening process employing docking softwares, for clustering the small molecule inhibitors based upon protein-ligand interactions.


Sign in / Sign up

Export Citation Format

Share Document