approach chemistry, functional and biological

Dithiocarbamates represent a class of compounds that were evaluated in different biomedical applications because of their chemical versatility. For this reason, several pharmacological activities have already been attributed to these compounds, such as antiparasitic, antiviral, antifungal activities, among others. Therefore, compounds that are based on dithiocarbamates have been evaluated in different in vivo and in vitro models as potential new antimicrobials. Thus, the purpose of this review is to present the possibilities of using dithiocarbamate compounds as potential new antitrypanosomatids-drugs, which could be used for the pharmacological control of Chagas disease, leishmaniasis, and African trypanosomiasis.publishersversionpublishe

Vlp-based vaccines as a suitable technology to target trypanosomatid diseases

Funding Information: This research was funded by Global Health and Tropical Medicine (Grant number IHMT UID/multi/04413/2013 and Grant number PTDC/CVT-CVT/28908/2017), Funda??o para Ci?ncia e Tecnologia (FCT), Portugal; Grant GIU18/172 Grupos de Investigaci?n de la UPV/EHU, and Grant from CSIC Programa I-COOP+2020 (ICOOPB20503), Spain.A.M.V.Q., J.W.d.F.O., and C.J.M. thanks to the financial support (PhD scholar-ships) provided by CNPq and CAPES, Brazil. M.S.S. thanks to CNPq for the Research Grant (Bolsa de Produtividade em Pesquisa). We are also grateful to Paulo Fanado and Laysa Ohanna for editing this manuscript. Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Research on vaccines against trypanosomatids, a family of protozoa that cause neglected tropical diseases, such as Chagas disease, leishmaniasis, and sleeping sickness, is a current need. Today, according to modern vaccinology, virus-like particle (VLP) technology is involved in many vaccines, including those undergoing studies related to COVID-19. The potential use of VLPs as vaccine adjuvants opens an opportunity for the use of protozoan antigens for the development of vaccines against diseases caused by Trypanosoma cruzi, Leishmania spp., and Trypanosoma brucei. In this context, it is important to consider the evasion mechanisms of these protozoa in the host and the antigens involved in the mechanisms of the parasite–host interaction. Thus, the immunostimulatory properties of VLPs can be part of an important strategy for the development and evaluation of new vaccines. This work aims to highlight the potential of VLPs as vaccine adjuvants for the development of immunity in complex diseases, specifically in the context of tropical diseases caused by trypanosomatids.publishersversionpublishe

In Vitro Validation of Antiparasitic Activity of PLA-Nanoparticles of Sodium Diethyldithiocarbamate against Trypanosoma cruzi

Funding Information: This research was funded by Global Health and Tropical Medicine: Grant number IHMT-UID/multi/04413/2013 and Grant number PTDC/CVT-CVT/28908/2017, FCT-Portugal.We would like to thank João Aristeu da Rosa and Aline Rimodi Rimeiro at UNESP (Universidade Estadual de São Paulo) Araraquara (Brazil) for offering four different strains of T. cruzi. JWFO and MFAS give thanks to their financial support (PhD and post-doctoral fellowships) provided by Capes/Brazil; MSS, AASJ, and HAOR give thanks to CNPq/Brazil for the Research Grant (Bolsa de Produtividade). We would also like to thank the Department of Materials Engineering at UFRN for affording us the use of their scanning electron microscope, and the Department of Biochemistry at UFRN for affording us the use of their culture room. We thank Laysa Ohana for reviewing and editing the English version of the manuscript. Publisher Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland.Trypanosoma cruzi is a protozoan parasite responsible for Chagas disease, which affects millions around the world and is not treatable in its chronic stage. Sodium diethyldithiocarbamate is a compound belonging to the carbamate class and, in a previous study, demonstrated high efficacy against T. cruzi, showing itself to be a promising compound for the treatment of Chagas disease. This study investigates the encapsulation of sodium diethyldithiocarbamate by poly-lactic acid in nanoparticles, a system of biodegradable nanoparticles that is capable of reducing the toxicity caused by free DETC against cells and maintaining the antiparasitic activity. The nanosystem PLA-DETC was fabricated using nanoprecipitation, and its physical characterization was measured via DLS, SEM, and AFM, demonstrating a small size around 168 nm and a zeta potential of around −19 mv. Furthermore, the toxicity was determined by MTT reduction against three cell lines (VERO, 3T3, and RAW), and when compared to free DETC, we observed a reduction in cell mortality, demonstrating the importance of DETC nanoencapsulation. In addition, the nanoparticles were stained with FITC and put in contact with cells for 24 h, followed by confirmation of whether the nanosystem was inside the cells. Lastly, the antiparasitic activity against different strains of T. cruzi in trypomastigote forms was determined by resazurin reduction and ROS production, which demonstrated high efficacy towards T. cruzi equal to that of free DETC.publishersversionpublishe

Silver Nanoparticles Containing Fucoidan Synthesized by Green Method Have Anti-Trypanosoma cruzi Activity

Funding Information: Funding: This research was funded by the Conselho Nacional de Desenvolvimento Científico e Tecnológico-CNPq (n◦ 408369/2016-7), Coordenação de Aperfeiçoamento Pessoal de Nível Superior (CAPES), Programa Ciências do Mar (AUXPE-CIMAR-1956/2014), and Programa Nacional de Cooperação Acadêmica (CAPES/PROCAD). Publisher Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland.The brown seaweed Spatoglossum schröederi synthesizes three bioactive fucoidans, the most abundant of which is fucan A. This fucoidan was extracted and its identity was confirmed by chemical analysis, Fourier-transform infrared spectroscopy (FTIR), and agarose gel electrophoresis. Thereafter, silver nanoparticles containing fucan A (AgFuc) were produced using an environmentally friendly synthesis method. AgFuc synthesis was analyzed via UV–vis spectroscopy and FTIR, which confirmed the presence of both silver and fucan A in the AgFuc product. Dynamic light scattering (DLS), X-ray diffraction, scanning electron microscopy, and atomic force microscopy revealed that the AgFuc particles were ~180.0 nm in size and spherical in shape. DLS further demonstrated that AgFuc was stable for five months. Coupled plasma optical emission spectrometry showed that the AgFuc particles contained 5% silver and 95% sugar. AgFuc was shown to be more effective in inhibiting the ability of parasites to reduce MTT than fucan A or silver, regardless of treatment time. In addition, AgFuc induced the death of ~60% of parasites by necrosis and ~17% by apoptosis. Therefore, AgFuc induces damage to the parasites’ mitochondria, which suggests that it is an anti-Trypanosoma cruzi agent. This is the first study to analyze silver nanoparticles containing fucan as an anti-Trypanosoma cruzi agent. Our data indicate that AgFuc nanoparticles have potential therapeutic applications, which should be determined via preclinical in vitro and in vivo studies.publishe

Antimicrobial Activity of Chitosan Oligosaccharides with Special Attention to Antiparasitic Potential

The global rise of infectious disease outbreaks and the progression of microbial resistance reinforce the importance of researching new biomolecules. Obtained from the hydrolysis of chitosan, chitooligosaccharides (COSs) have demonstrated several biological properties, including antimicrobial, and greater advantage over chitosan due to their higher solubility and lower viscosity. Despite the evidence of the biotechnological potential of COSs, their effects on trypanosomatids are still scarce. The objectives of this study were the enzymatic production, characterization, and in vitro evaluation of the cytotoxic, antibacterial, antifungal, and antiparasitic effects of COSs. NMR and mass spectrometry analyses indicated the presence of a mixture with 81% deacetylated COS and acetylated hexamers. COSs demonstrated no evidence of cytotoxicity upon 2 mg/mL. In addition, COSs showed interesting activity against bacteria and yeasts and a time-dependent parasitic inhibition. Scanning electron microscopy images indicated a parasite aggregation ability of COSs. Thus, the broad biological effect of COSs makes them a promising molecule for the biomedical industry.publishersversionpublishe

Insights of antiparasitic activity of sodium diethyldithiocarbamate against different strains of Trypanosoma cruzi

Funding Information: This research was funded by Global Health and Tropical Medicine: Grant number IHMT-UID/multi/04413/2013 and Grant number PTDC/CVT-CVT/28908/2017, FCT-Portugal. Funding Information: We would like to thank Prof. João Aristeu da Rosa and Dr. Aline Rimodi Rimeiro at UNESP (Universidade Estadual de São Paulo) Araraquara (Brazil) for offering four different strains of T. cruzi. JWFO, CJGM, and BAC thanks to the financial support (PhD and Post-doctoral fellowships) provided by Capes/Brazil; MSS and HAOR thanks to CNPq/Brazil for the Research Grant (Bolsa de Produtividade). We also would like to thank the Department of Materials Engineering at UFRN for allowing the use of their scanning electron microscope, and the Department of Biochemistry at UFRN for allowing the use of their Flow Cytometer. We are also grateful to Paulo Fanado for editing this manuscript. Publisher Copyright: © 2021, The Author(s).Chagas disease is caused by Trypanosoma cruzi and affects thousands of people. Drugs currently used in therapy are toxic and have therapeutic limitations. In addition, the genetic diversity of T. cruzi represents an important variable and challenge in treatment. Sodium diethyldithiocarbamate (DETC) is a compound with pharmacological versatility acting as metal chelators and ROS generation. Thus, the objective was to characterize the antiparasitic action of DETC against different strains and forms of T. cruzi and their mechanism. The different strains of T. cruzi were grown in LIT medium. To evaluate the antiparasitic activity of DETC, epimastigote and trypomastigote forms of T. cruzi were used by resazurin reduction methods and by counting. Different response patterns were obtained between the strains and an IC50 of DETC ranging from 9.44 ± 3,181 to 60.49 ± 7.62 µM. Cell cytotoxicity against 3T3 and RAW cell lines and evaluated by MTT, demonstrated that DETC in high concentration (2222.00 µM) presents low toxicity. Yet, DETC causes mitochondrial damage in T. cruzi, as well as disruption in parasite membrane. DETC has antiparasitic activity against different genotypes and forms of T. cruzi, therefore, representing a promising molecule as a drug for the treatment of Chagas disease.publishersversionpublishe

Bisphosphonate-based molecules as potential new antiparasitic drugs

Neglected tropical diseases such as Chagas disease and leishmaniasis affect millions of people around the world. Both diseases affect various parts of the globe and drugs traditionally used in therapy against these diseases have limitations, especially with regard to low efficacy and high toxicity. In this context, the class of bisphosphonate-based compounds has made significant advances regarding the chemical synthesis process as well as the pharmacological properties attributed to these compounds. Among this spectrum of pharmacological activity, bisphosphonate compounds with antiparasitic activity stand out, especially in the treatment of Chagas disease and leishmaniasis caused by Trypanosoma cruzi and Leishmania spp., respectively. Some bisphosphonate compounds can inhibit the mevalonate pathway, an essential metabolic pathway, by interfering with the synthesis of ergosterol, a sterol responsible for the growth and viability of these parasites. Therefore, this review aims to present the information about the importance of these compounds as antiparasitic agents and as potential new drugs to treat Chagas disease and leishmaniasis.publishersversionpublishe

Cell Culture and Maintenance of the Evolutionary Forms of <em>Trypanosoma cruzi</em> for Studies of Parasitic Biology

This chapter aims to present and discuss the main cell culture techniques used for the growth and maintenance of the different evolutionary forms of the protozoan Trypanosoma cruzi, the etiologic agent of the Chagas disease. Chagas disease is a neglected tropical disease endemic in several Latin American countries. Here, we intend to present the main difficulties, advantages, and disadvantages of using Trypanosoma cruzi cell culture in parasitic biology. Finally, we present the main research opportunities in the context of Trypanosoma cruzi parasitic biology using cell culture techniques, such as drug development, characterization of pharmacological targets, molecular markers for diagnosis, structural biology, and many other biomedical applications

The evaluation of in vitro antichagasic and anti-SARS-CoV-2 potential of inclusion complexes of β- and methyl-β-cyclodextrin with naphthoquinone

Funding Information: The authors thank the Coordination for the Improvement of Higher Education Personnel (CAPES) and the National Council for Scientific and Technological Development (CNPq) for their financial support. This study was supported by the CAPES — number 88887.505029/2020–00 . Cecilia Gomes Barbosa receives a scholarship funded by CAPES — number 88887.643352/2021–00 . Publisher Copyright: © 2023 Elsevier B.V.The compound 3a,10b-dihydro-1H-cyclopenta[b]naphtho[2,3-d]furan-5,10-dione (IVS320) is a naphthoquinone with antifungal and antichagasic potential, which however has low aqueous solubility. To increase bioavailability, inclusion complexes with β-cyclodextrin (βCD) and methyl-β-cyclodextrin (MβCD) were prepared by physical mixture (PM), kneading (KN) and rotary evaporation (RE), and their in vitro anti-SARS-CoV-2 and antichagasic potential was assessed. The formation of inclusion complexes led to a change in the physicochemical characteristics compared to IVS320 alone as well as a decrease in crystallinity degree that reached 74.44% for the IVS320-MβCD one prepared by RE. The IVS320 and IVS320-MβCD/RE system exhibited anti-SARS-CoV-2 activity, showing half maximal effective concentrations (EC50) of 0.47 and 1.22 μg/mL, respectively. Molecular docking simulation suggested IVS320 ability to interact with the SARS-CoV-2 viral protein. Finally, the highest antichagasic activity, expressed as percentage of Tripanosoma cruzi growth inhibition, was observed with IVS320-βCD/KN (70%) and IVS320-MβCD/PM (72%), while IVS320 alone exhibited only approximately 48% inhibition at the highest concentration (100 μg/mL).publishersversionpublishe

Quantum Biochemistry Screening and In Vitro Evaluation of Leishmania Metalloproteinase Inhibitors

Funding Information: Global Health and Tropical Medicine funded this research: Grant number IHMT-UID/multi/04413/2013 and Grant number PTDC/CVT-CVT/28908/2017, FCT-Portugal. Funding Information: We would like to thank to CNPq/Brazil, CAPES/Brazil and FCT/Portugal for grants and fellowships. C.J.G.M., J.W.d.F.O., T.K.d.B.P., F.L.d.S.J. and B.A.-C. thank the financial support (PhD and Post-doctoral fellowships) provided by Capes/Brazil. M.S.S. and H.A.O.R. thank CNPq/Brazil for the Research Grant (Bolsa de Produtividade em Pesquisa). We also would like to thank the Department of Materials Engineering at UFRN for allowing the use of their scanning electron microscope, and the Department of Biochemistry at UFRN for allowing the use of their flow cytometer. Publisher Copyright: © 2022 by the authors.Leishmanolysin, also known as major promastigote protease (PSP) or gp63, is the most abundant surface glycoprotein of Leishmania spp., and has been extensively studied and recognized as the main parasite virulence factor. Characterized as a metalloprotease, gp63 can be powerfully inactivated in the presence of a metal chelator. In this study, we first used the structural parameters of a 7-hydroxycoumarin derivative, L1 compound, to evaluate the theoretical–computational experiments against gp63, comparing it with an available metal chelator already described. The methodology followed was (i) analysis of the three-dimensional structure of gp63 as well as its active site, and searching the literature and molecular databases for possible inhibitors; (ii) molecular docking simulations and investigation of the interactions in the generated protein–ligand complexes; and (iii) the individual energy of the gp63 amino acids that interacted most with the ligands of interest was quantified by ab initio calculations using Molecular Fraction with Conjugated Caps (MFCC). MFCC still allowed the final quantum balance calculations of the protein interaction to be obtained with each inhibitor candidate binder. L1 obtained the best energy quantum balance result with −2 eV, followed by DETC (−1.4 eV), doxycycline (−1.3 eV), and 4-terpineol (−0.6 eV), and showed evidence of covalent binding in the enzyme active site. In vitro experiments confirmed L1 as highly effective against L. amazonensis parasites. The compound also exhibited a low cytotoxicity profile against mammalian RAW and 3T3 cells lines, presenting a selective index of 149.19 and 380.64 µM, respectively. L1 induced promastigote forms’ death by necrosis and the ultrastructural analysis revealed disruption in membrane integrity. Furthermore, leakage of the contents and destruction of the parasite were confirmed by Spectroscopy Dispersion analysis. These results together suggested L1 has a potential effect against L. amazonensis, the etiologic agent of diffuse leishmaniasis, and the only one that currently does not have a satisfactory treatment.publishersversionpublishe