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1.
Nat Methods ; 21(6): 1114-1121, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38594452

RESUMO

The identification of genetic and chemical perturbations with similar impacts on cell morphology can elucidate compounds' mechanisms of action or novel regulators of genetic pathways. Research on methods for identifying such similarities has lagged due to a lack of carefully designed and well-annotated image sets of cells treated with chemical and genetic perturbations. Here we create such a Resource dataset, CPJUMP1, in which each perturbed gene's product is a known target of at least two chemical compounds in the dataset. We systematically explore the directionality of correlations among perturbations that target the same protein encoded by a given gene, and we find that identifying matches between chemical and genetic perturbations is a challenging task. Our dataset and baseline analyses provide a benchmark for evaluating methods that measure perturbation similarities and impact, and more generally, learn effective representations of cellular state from microscopy images. Such advancements would accelerate the applications of image-based profiling of cellular states, such as uncovering drug mode of action or probing functional genomics.


Assuntos
Processamento de Imagem Assistida por Computador , Humanos , Processamento de Imagem Assistida por Computador/métodos , Microscopia/métodos
2.
Int J Parasitol Drugs Drug Resist ; 24: 100531, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38484645

RESUMO

Leishmaniasis and Chagas disease are parasitic infections that affect millions of people worldwide, producing thousands of deaths per year. The current treatments against these pathologies are not totally effective and produce some side effects in the patients. Acrylonitrile derivatives are a group of compounds that have shown activity against these two diseases. In this work, four novels synthetic acrylonitriles were evaluated against the intracellular form and extracellular forms of L. amazonensis and T. cruzi. The compounds 2 and 3 demonstrate to have good selectivity indexes against both parasites, specifically the compound 3 against the amastigote form (SI = 6 against L. amazonensis and SI = 7.4 against T. cruzi). In addition, the parasites treated with these two compounds demonstrate to produce a programmed cell death, since they were positive for the events studied related to this type of death, including chromatin condensation, accumulation of reactive oxygen species and alteration of the mitochondrial membrane potential. In conclusion, this work confirms that acrylonitriles is a source of possible new compounds against kinetoplastids, however, more studies are needed to corroborate this activity.


Assuntos
Acrilonitrila , Antiprotozoários , Doença de Chagas , Leishmania mexicana , Trypanosoma cruzi , Humanos , Antiprotozoários/farmacologia , Acrilonitrila/farmacologia , Acrilonitrila/uso terapêutico , Doença de Chagas/tratamento farmacológico , Morte Celular
3.
Pharmaceuticals (Basel) ; 17(3)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38543052

RESUMO

Leishmaniasis, a neglected tropical disease, poses a significant global health challenge, necessitating the urgent development of innovative therapies. In this study, we aimed to identify compounds from the COVID Box with potential efficacy against two Leishmania species, laying the foundation for future chemical development. Four promising molecules were discovered, demonstrating notable inhibitory effects against L. amazonensis and L. donovani. Our study revealed that bortezomib, almitrine, and terconazole induced a significant decrease in mitochondrial membrane potential, while the above compounds and ABT239 induced plasma permeability alterations, chromatin condensation, and reactive oxygen species accumulation, indicating early apoptosis in Leishmania amazonensis promastigotes, preventing inflammatory responses and tissue damage, thereby improving patient outcomes. Furthermore, ADME predictions revealed favorable pharmacokinetic profiles for all compounds, with bortezomib and ABT239 standing out as potential candidates. These compounds exhibited intestinal absorption, blood-brain barrier penetration (excluding bortezomib), and good drug-likeness for bortezomib and ABT239. Toxicity predictions for CYP-inhibition enzymes favored bortezomib as the safest candidate. In conclusion, our study identifies bortezomib as a promising aspirant for leishmaniasis treatment, demonstrating potent antiparasitic activity, favorable pharmacokinetics, and low toxicity. These findings emphasize the potential repurposing of existing drugs for neglected diseases and highlight the importance of the COVID Box in drug discovery against tropical diseases.

4.
Int J Med Mushrooms ; 25(9): 63-72, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37824406

RESUMO

The genus Ganoderma has a long history of use in traditional Asiatic medicine due to its different nutritional and medicinal properties. In Mexico, the species G. tuberculosum is used in indigenous communities, for example, the Wixaritari and mestizos of Villa Guerrero Jalisco for the treatment of diseases that may be related to parasitic infections; however, few chemical studies corroborate its traditional medicinal potential. Thereby, the objective of this study was to isolate and identify anti-parasitic activity compounds from a strain of G. tuberculosum native to Mexico. From the fruiting bodies of G. tuberculosum (GVL-21) a hexane extract was obtained which was subjected to guided fractioning to isolate pure compounds. The in vitro anti-parasitic activity of the pure compound (IC50) was assayed against Leishmania amazonensis, Trypanosoma cruzi, Acanthamoeba castellanii Neff, and Naegleria fowleri. Furthermore, the cytotoxicity (CC50) of the isolated compounds was determined against murine macrophages. The guided fractioning produced 5 compounds: ergosterol (1), ergosta-4,6,8(14),22-tetraen-3-one (2), ergosta-7,22-dien-3ß-ol (3), 3,5-dihydroxy-ergosta-7,22-dien-6-one (4), and ganoderic acid DM (5). Compounds 2 and 5 showed the best anti-parasitic activity in an IC50 range of 54.34 ± 8.02 to 12.38 ± 2.72 µM against all the parasites assayed and low cytotoxicity against murine macrophages. The present study showed for the first time the in vitro anti-parasitic activity of compounds 1-5 against L. amazonensis, T. cruzi, A. castellanii Neff, and N. fowleri, corroborating the medicinal potential of Ganoderma and its traditional applications.


Assuntos
Anti-Infecciosos , Ganoderma , Animais , Camundongos , Antiparasitários , México , Ganoderma/química
5.
Pharmaceuticals (Basel) ; 16(7)2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37513922

RESUMO

Naegleria fowleri is the causative agent of a central nervous system affecting disease called primary amoebic meningoencephalitis. It is a fulminant disease with a rapid progression that affects mainly children and young adults who report previous water exposure. Current treatment options are not totally effective and involve several side effects. In this work, six meroterpenoids isolated from the brown algae Gongolaria abies-marina were evaluated against N. fowleri. Gongolarone B (1), 6Z-1'-methoxyamentadione (2), and 1'-methoxyamentadione (3) were the most active molecules against N. fowleri with IC50 values between 13.27 ± 0.96 µM and 21.92 ± 1.60 µM. However, cystomexicone B (6) was the molecule with the highest selectivity index (>8.5). Moreover, all these compounds induced different cellular events compatible with the apoptosis-like PCD process, such as chromatin condensation, damages at the mitochondrial level, cell membrane disruption, and production of reactive oxygen species (ROS). Therefore, G. abies-marina could be considered as a promising source of active molecules to treat the N. fowleri infections.

6.
Artigo em Inglês | MEDLINE | ID: mdl-37311268

RESUMO

Chagas disease causes a problematic pathology that can lead to megacolon and heart disease, and can even cause the death of the patient. Current therapies for this disease are the same as they were 50 years ago, are not fully effective and have strong side effects. The lack of a safe and effective therapy makes it necessary to search for new, less toxic and totally effective compounds against this parasite. In this work, the antichagasic activity of 46 novel cyanomethyl vinyl ether derivatives was studied. In addition, to elucidate the type of cell death that these compounds produce in parasites, several events related to programmed cell death were studied. The results highlight four more selective compounds, E63, E64, E74 and E83, which also appear to trigger programmed cell death, and are therefore postulated as good candidates to use in future therapeutics for Chagas disease.


Assuntos
Doença de Chagas , Parasitos , Tripanossomicidas , Trypanosoma cruzi , Animais , Humanos , Tripanossomicidas/farmacologia , Tripanossomicidas/uso terapêutico , Doença de Chagas/tratamento farmacológico , Doença de Chagas/parasitologia , Morte Celular , Éteres/uso terapêutico
7.
Mar Drugs ; 21(6)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37367658

RESUMO

Among neglected tropical diseases, leishmaniasis is one of the leading causes, not only of deaths but also of disability-adjusted life years. This disease, caused by protozoan parasites of the genus Leishmania, triggers different clinical manifestations, with cutaneous, mucocutaneous, and visceral forms. As existing treatments for this parasitosis are not sufficiently effective or safe for the patient, in this work, different sesquiterpenes isolated from the red alga Laurencia johnstonii have been studied for this purpose. The different compounds were tested in vitro against the promastigote and amastigote forms of Leishmania amazonensis. Different assays were also performed, including the measurement of mitochondrial potential, determination of ROS accumulation, and chromatin condensation, among others, focused on the detection of the cell death process known in this type of organism as apoptosis-like. Five compounds were identified that displayed leishmanicidal activity: laurequinone, laurinterol, debromolaurinterol, isolaurinterol, and aplysin, showing IC50 values against promastigotes of 1.87, 34.45, 12.48, 10.09, and 54.13 µM, respectively. Laurequinone was the most potent compound tested and was shown to be more effective than the reference drug miltefosine against promastigotes. Different death mechanism studies carried out showed that laurequinone appears to induce programmed cell death or apoptosis in the parasite studied. The obtained results underline the potential of this sesquiterpene as a novel anti-kinetoplastid therapeutic agent.


Assuntos
Antiprotozoários , Leishmania mexicana , Leishmania , Leishmaniose , Humanos , Animais , Camundongos , Leishmaniose/tratamento farmacológico , Pele , Extratos Vegetais/farmacologia , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Camundongos Endogâmicos BALB C
8.
Nat Protoc ; 18(7): 1981-2013, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37344608

RESUMO

In image-based profiling, software extracts thousands of morphological features of cells from multi-channel fluorescence microscopy images, yielding single-cell profiles that can be used for basic research and drug discovery. Powerful applications have been proven, including clustering chemical and genetic perturbations on the basis of their similar morphological impact, identifying disease phenotypes by observing differences in profiles between healthy and diseased cells and predicting assay outcomes by using machine learning, among many others. Here, we provide an updated protocol for the most popular assay for image-based profiling, Cell Painting. Introduced in 2013, it uses six stains imaged in five channels and labels eight diverse components of the cell: DNA, cytoplasmic RNA, nucleoli, actin, Golgi apparatus, plasma membrane, endoplasmic reticulum and mitochondria. The original protocol was updated in 2016 on the basis of several years' experience running it at two sites, after optimizing it by visual stain quality. Here, we describe the work of the Joint Undertaking for Morphological Profiling Cell Painting Consortium, to improve upon the assay via quantitative optimization by measuring the assay's ability to detect morphological phenotypes and group similar perturbations together. The assay gives very robust outputs despite various changes to the protocol, and two vendors' dyes work equivalently well. We present Cell Painting version 3, in which some steps are simplified and several stain concentrations can be reduced, saving costs. Cell culture and image acquisition take 1-2 weeks for typically sized batches of ≤20 plates; feature extraction and data analysis take an additional 1-2 weeks.This protocol is an update to Nat. Protoc. 11, 1757-1774 (2016): https://doi.org/10.1038/nprot.2016.105.


Assuntos
Técnicas de Cultura de Células , Processamento de Imagem Assistida por Computador , Processamento de Imagem Assistida por Computador/métodos , Microscopia de Fluorescência , Mitocôndrias , Software
9.
Biomed Pharmacother ; 164: 114879, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37210899

RESUMO

Leishmaniasis and Chagas disease, two of the most prevalent neglected tropical diseases, are a world health problem. The harsh reality of these infective diseases is the absence of effective and safe therapies. In this framework, natural products play an important role in overcoming the current need to development new antiparasitic agents. The present study reports the synthesis, antikinetoplastid screening, mechanism study of fourteen withaferin A derivatives (2-15). Nine of them (2-6, 8-10 and 12) showed a potent dose-dependent inhibitory effect on the proliferation of Leishmania amazonensis and L. donovani promastigotes and Trypanosoma cruzi epimastigotes with IC50 values ranging from 0.19 to 24.01 µM. Outstandingly, the fully acetylated derivative 10 (4,27-diacetylwithaferin A) was the most potent compound showing IC50 values of 0.36, 2.82 and 0.19 µM against L. amazonensis, L. donovani and T. cruzi, respectively. Furthermore, analogue 10 exhibited approximately 18 and 36-fold greater antikinetoplastid activity, on L. amazonensis and T. cruzi, than the reference drugs. The activity was accompanied by significantly lower cytotoxicity on the murine macrophage cell line. Moreover, compounds 2, 3, 5-7, 9 and 10 showed more potent activity than the reference drug against the intracellular amastigotes forms of L. amazonensis and T.cruzi, with a good selectivity index on a mammalian cell line. In addition, withaferin A analogues 3, 5-7, 9 and 10 induce programmed cell death through a process of apoptosis-like and autophagy. These results strengthen the anti-parasitic potential of withaferin A-related steroids against neglected tropical diseases caused by Leishmania spp. and T. cruzi parasites.


Assuntos
Antiprotozoários , Doença de Chagas , Leishmania , Animais , Camundongos , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Testes de Sensibilidade Parasitária , Doença de Chagas/tratamento farmacológico , Apoptose , Mamíferos
10.
Pharmaceuticals (Basel) ; 16(4)2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-37111233

RESUMO

Leishmaniasis and Chagas disease affect millions of people worldwide. The available treatments against these parasitic diseases are limited and display multiple undesired effects. The brown alga belonging to the genus Gongolaria has been previously reported as a source of compounds with different biological activities. In a recent study from our group, Gongolaria abies-marine was proven to present antiamebic activity. Hence, this brown alga could be a promising source of interesting molecules for the development of new antiprotozoal drugs. In this study, four meroterpenoids were isolated and purified from a dichloromethane/ethyl acetate crude extract through a bioguided fractionation process targeting kinetoplastids. Moreover, the in vitro activity and toxicity were evaluated, and the induction of programmed cell death was checked in the most active and less toxic compounds, namely gongolarone B (2), 6Z-1'-methoxyamentadione (3) and 1'-methoxyamentadione (4). These meroterpenoids triggered mitochondrial malfunction, oxidative stress, chromatin condensation and alterations of the tubulin network. Furthermore, a transmission electron microscopy (TEM) image analysis showed that meroterpenoids (2-4) induced the formation of autophagy vacuoles and ER and Golgi complex disorganization. The obtained results demonstrated that the mechanisms of action at the cellular level of these compounds were able to induce autophagy as well as an apoptosis-like process in the treated parasites.

11.
Biomed Pharmacother ; 158: 114185, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36916403

RESUMO

Free Living Amoeba (FLA) infections caused by Acanthamoeba genus include chronic nervous system diseases such as Granulomatous Amoebic Encephalitis (GAE), or a severe eye infection known as Acanthamoeba keratitis (AK). Current studies focused on therapy against these diseases are aiming to find novel compounds with amoebicidal activity and low toxicity to human tissues. Brown algae, such as Gongolaria abies-marina (previously known as Cystoseira abies-marina, S.G. Gmelin), presents bioactive molecules of interest, including some with antiprotozoal activity. In this study, six meroterpenoids were isolated and purified from the species Gongolaria abies-marina. Gongolarones A (1), B (2) and C (3) were identified as new compounds. Additionally, cystomexicone B (4), 1'-methoxyamentadione (5) and 6Z-1'-methoxyamentadione (6) were isolated. All compounds exhibited amoebicidal activity against Acanthamoeba castellanii Neff, A. polyphaga and A. griffini strains. Gongolarones A (1) and C (3) showed the lowest IC50 values against the two stages of these amoebae (trophozoite and cyst). Structure-activity relationship revealed that the cyclization by ether formation from C-12 to C-15 of 1, and the isomerization Δ2 t to Δ3 t of 3, increased the antiamoeboid activity of both compounds. Furthermore, gongolarones A (1) and C (3) triggered chromatin condensation, mitochondrial malfunction, oxidative stress, and disorganization of the tubulin-actin cytoskeleton in treated trophozoites. Moreover, transmission electron microscopy (TEM) images analysis revealed that compounds 1 and 3 induced autophagy process and inhibited the encystation process. All those results suggest that both compounds could induce programmed cell death (PCD) in Acanthamoeba.


Assuntos
Acanthamoeba castellanii , Amebicidas , Animais , Humanos , Amebicidas/farmacologia , Trofozoítos , Citoesqueleto de Actina
12.
Biomed Pharmacother ; 157: 114012, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36399830

RESUMO

Current therapies of leishmaniasis and Chagas disease, two of the most widespread neglected tropical diseases, have limited efficacy and toxic side effects. In this regard, natural products play an important role in overcoming the current need for new antiparasitic agents. The present study reports the leishmanicidal and trypanocidal activities of twenty-four known silyl-ether derivatives of withaferin A. Eleven compounds from this series (4, 7, 8, 10, 12, 15, 17, 18, 20, 22 and 25) showed a potent dose-dependent inhibitory effect on the proliferation of Leishmania amazonensis promastigotes and Trypanosoma cruzi epimastigotes respectively, even higher than the references drugs, miltefosine and benznidazole. Among them, the most promising compound, derivative 10, exhibited approximately 34-fold higher leishmanicidal activity and 49-fold higher trypanocidal activity compared to the reference drugs, as well as lower cytotoxicity. Moreover, compounds 4, 7, 10, 12 and 15 were more active than the reference drugs against the amastigote forms of L. amazonensis, presenting a high selectivity index. Assays performed to study the ATP levels, mitochondrial membrane potential, plasma membrane permeability, chromatin condensation, reactive oxygen species and autophagy indicated that these withaferin A-silyl analogs appear to induce events characteristic of apoptosis-like and also autophagy leading to programmed cell death. These findings support the therapeutic potential of withaferin A-related steroids as anti-Leishmania and Trypanosoma agents.


Assuntos
Antiprotozoários , Doença de Chagas , Leishmania , Tripanossomicidas , Trypanosoma cruzi , Humanos , Éter , Doença de Chagas/tratamento farmacológico , Apoptose , Tripanossomicidas/farmacologia , Tripanossomicidas/uso terapêutico , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico
13.
Bioorg Chem ; 124: 105872, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35597192

RESUMO

Leishmaniasis produces approximately-one million of new cases annually, making it one of the most important tropical diseases. As current treatments are not fully effective and are toxic, it is necessary to develop new therapies that are more effective and less toxic, and cause a controlled cell death, with which we can avoid the immunological problems caused by necrosis. In this work 32 acrylonitriles were studied in vitro against Leishmania amazonensis. Three compounds Q20 (12.41), Q29 (11.2) and Q31 (11.56) had better selectivity than the reference compound, miltefosine (11.14) against promastigotes of these parasites, for this reason they were selected to determine their mechanism of action to know the cell death type of they produce. The results of the mechanisms of action show that these three acrylonitriles tested produce chromatin condensation, decreased mitochondrial membrane potential, altered plasma permeability and production of reactive oxygen species. All these characteristic events seem to indicate programmed cell death. Therefore, this study demonstrates the activity of acrylonitriles derivatives as possible leishmanicidal agents.


Assuntos
Acrilonitrila , Antiprotozoários , Leishmania mexicana , Acrilonitrila/metabolismo , Acrilonitrila/farmacologia , Animais , Antiprotozoários/metabolismo , Morte Celular , Macrófagos , Camundongos , Camundongos Endogâmicos BALB C
14.
Pharmaceuticals (Basel) ; 14(12)2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34959620

RESUMO

The protozoan parasite Leishmania causes a spectrum of diseases and there are over 1 million infections each year. Current treatments are toxic, expensive, and difficult to administer, and resistance to them is emerging. In this study, we screened the antileishmanial activity of the Pathogen Box compounds from the Medicine for Malaria Venture against Leishmania amazonensis, and compared their structures and cytotoxicity. The compounds MMV676388 (3), MMV690103 (5), MMV022029 (7), MMV022478 (9) and MMV021013 (10) exerted a significant dose-dependent inhibition effect on the proliferation of L. amazonensis promastigotes and intracellular amastigotes. Moreover, studies on the mechanism of cell death showed that compounds 3 and 5 induced an apoptotic process while the compounds 7, 9 and 10 seem to induce an autophagic mechanism. The present findings underline the potential of these five molecules as novel therapeutic leishmanicidal agents.

15.
Pharmaceuticals (Basel) ; 14(11)2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34832876

RESUMO

Leishmaniasis and Chagas disease are neglected tropical diseases that cause problems in developing countries. The causative agents, Leishmania spp. and Trypanosoma cruzi, produce a clinical picture that can be fatal for the patient, such as Chagas heart disease, visceral leishmaniasis and megacolon, among others. Current treatments for these diseases are not very effective and highly toxic, since they require very prolonged treatments. The development of innovative, effective and safe drugs to fight infections caused by these parasites remains a challenge. For this reason, in recent years, there has been an increase in the search for new therapies. In this study, the antikinetoplastid activity of 13 sesquiterpene lactones obtained from Palythoa aff. clavata was screened against L. amazonensis, L. donovani and T. cruzi. The results revealed that the sesquiterpene lactones anhydroartemorin (2), cis,trans-costunolide-14-acetate (3) and 4-hydroxyarbusculin A (11) were the most selective against the kinetoplastid species studied. These molecules seem to induce the mechanisms involved in an apoptotic-like death or programmed cell death (PCD) in the kinetoplastids, and since they do not cause necrosis, the inflammatory events associated with this type of cell death will not be triggered.

16.
Pharmaceuticals (Basel) ; 14(6)2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34207767

RESUMO

The neglected infection known as Chagas disease, caused by the protozoan parasite Trypanosoma cruzi, results in more than 7000 deaths per year, with an increasing number of cases in non-endemic areas such as Europe or the United States. Moreover, with the current available therapy, only two compounds which are active against the acute phase of the disease are readily available. In addition, these therapeutic agents display multiple undesired side effects such as high toxicity, they are expensive, the treatment is lengthy and the resistant strain has emerged. Therefore, there is a need to find new compounds against Chagas disease which should be active against the parasite but also cause low toxicity to the patients. In the present work, the activity of novel acrylonitriles against Trypanosoma cruzi was evaluated as well as the analysis of the physiological events induced in the treated parasites related to the cell death process. Hence, the characteristic features of an apoptosis-like process such as chromatin condensation and mitochondrial membrane potential, among others, were studied. From the 32 compounds tested against the epimastigote stage of T. cruzi, 11 were selected based on their selectivity index to determine if these compounds were able to induce programmed cell death (PCD) in the treated parasites. Furthermore, acrylonitriles Q5, Q7, Q19, Q27 and Q29 were shown to trigger physiological events related in the PCD. Therefore, this study highlights the therapeutic potential of acrylonitriles as novel trypanocidal agents.

17.
Artigo em Inglês | MEDLINE | ID: mdl-33753334

RESUMO

Leishmaniasis and Chagas are among the most significant neglected tropical diseases. Due to several drawbacks with the current chemotherapy, developing new antikinetoplastid drugs has become an urgent issue. In the present work, a bioassay-guided investigation of the root bark of Maytenus chiapensis on Leishmania amazonensis and Trypanosoma cruzi led to the identification of two D:A-friedo-nor-oleanane triterpenoids (celastroloids), 20ß-hydroxy-tingenone (celastroloid 5) and 3-O-methyl-6-oxo-tingenol (celastroloid 8), as promising antikinetoplastid leads. They displayed higher potency on L. amazonensis promastigotes (50% inhibitory concentrations [IC50s], 0.44 and 1.12 µM, respectively), intracellular amastigotes (IC50s, 0.83 and 1.91 µM, respectively), and T. cruzi epimastigote stage (IC50s, 2.61 and 3.41 µM, respectively) than reference drugs miltefosine and benznidazole. This potency was coupled with an excellent selectivity index on murine macrophages. Mechanism of action studies, including mitochondrial membrane potential (Δψm) and ATP-level analysis, revealed that celastroloids could induce apoptotic cell death in L. amazonensis triggered by the mitochondria. In addition, the structure-activity relationship is discussed. These findings strongly underline the potential of celastroloids as lead compounds to develop novel antikinetoplastid drugs.


Assuntos
Antiprotozoários , Leishmania mexicana , Leishmaniose , Maytenus , Trypanosoma cruzi , Animais , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Leishmaniose/tratamento farmacológico , Camundongos
18.
Mol Cancer Res ; 19(6): 1015-1025, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33619228

RESUMO

FANCJ (BRIP1/BACH1) is a hereditary breast and ovarian cancer (HBOC) gene encoding a DNA helicase. Similar to HBOC genes, BRCA1 and BRCA2, FANCJ is critical for processing DNA inter-strand crosslinks (ICL) induced by chemotherapeutics, such as cisplatin. Consequently, cells deficient in FANCJ or its catalytic activity are sensitive to ICL-inducing agents. Unfortunately, the majority of FANCJ clinical mutations remain uncharacterized, limiting therapeutic opportunities to effectively use cisplatin to treat tumors with mutated FANCJ. Here, we sought to perform a comprehensive screen to identify FANCJ loss-of-function (LOF) mutations. We developed a FANCJ lentivirus mutation library representing approximately 450 patient-derived FANCJ nonsense and missense mutations to introduce FANCJ mutants into FANCJ knockout (K/O) HeLa cells. We performed a high-throughput screen to identify FANCJ LOF mutants that, as compared with wild-type FANCJ, fail to robustly restore resistance to ICL-inducing agents, cisplatin or mitomycin C (MMC). On the basis of the failure to confer resistance to either cisplatin or MMC, we identified 26 missense and 25 nonsense LOF mutations. Nonsense mutations elucidated a relationship between location of truncation and ICL sensitivity, as the majority of nonsense mutations before amino acid 860 confer ICL sensitivity. Further validation of a subset of LOF mutations confirmed the ability of the screen to identify FANCJ mutations unable to confer ICL resistance. Finally, mapping the location of LOF mutations to a new homology model provides additional functional information. IMPLICATIONS: We identify 51 FANCJ LOF mutations, providing important classification of FANCJ mutations that will afford additional therapeutic strategies for affected patients.


Assuntos
Proteína BRCA1/genética , DNA Helicases/genética , Análise Mutacional de DNA/métodos , Proteínas de Grupos de Complementação da Anemia de Fanconi/genética , Mutação/genética , Neoplasias/genética , RNA Helicases/genética , Linhagem Celular Tumoral , Cisplatino/farmacologia , Códon sem Sentido , Reagentes de Ligações Cruzadas/farmacologia , Técnicas de Inativação de Genes , Células HeLa , Humanos , Mutação com Perda de Função , Mitomicina/farmacologia , Mutação/efeitos dos fármacos , Mutação de Sentido Incorreto , Neoplasias/patologia
19.
Biomed Pharmacother ; 132: 110814, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33086179

RESUMO

The in vitro activity against Leishmania spp. of five novel designed compounds, phenalenone derivatives, is described in this study. Previous works have shown that some phenalenones present leishmanicidal activity, some of which could induce programmed cell death events in L. amazonensis parasites. In this research, we focused on the determination of the programmed cell death evidence by detecting the characteristic features of the apoptosis-like process, such as phosphatidylserine exposure and mitochondrial membrane potential, among others. The results showed that the new derivatives have comparable or better activity and selectivity than the commonly prescribed anti-leishmanial drug. This result was obtained by inducing stronger mitochondrial depolarization or more intense phosphatidylserine exposure than miltefosine, highlighting compound 8 with moreover 9-times better selectivity index. In addition, the new five molecules activated the apoptosis-like process in the parasite. All the signals observed were indicative of the death process that the parasites were undergoing.


Assuntos
Antiprotozoários/farmacologia , Leishmania/efeitos dos fármacos , Fenalenos/farmacologia , Antiprotozoários/química , Apoptose/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Fenalenos/química , Fosforilcolina/análogos & derivados , Fosforilcolina/farmacologia
20.
Pathogens ; 9(5)2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32380785

RESUMO

Free living, cosmopolitan amoebae from Acanthamoeba genus present a serious risk to human health. As facultative human parasites, these amoebae may cause Acanthamoeba keratitis (AK). Acanthamoeba keratitis is a severe, vision-threatening corneal infection with non-specific symptoms. The number of reported AK cases worldwide has been increasing every year. Moreover, 90% of Acanthamoeba keratitis cases are related to contact lens use. Wearing and storage contact lenses not in accordance with the physicians and manufacturers recommendations are the primary key risk factors of this disease. Amoebae can easily adhere to the contact lens surface and transmit to the corneal epithelium. Preventing amoebae adhesion to the contact lens surface could significantly decrease the number of AK infections. Until now, the effective therapy against AK is still under development. Currently proposed therapies are mainly limited to the chlorhexidine digluconate combined with propamidine isethionate or hexamidine applications, which are insufficient and very toxic to the eye. Due to lack of effective treatment, looking for new potential preventive agents is crucial to decrease the number of Acanthamoeba keratitis infections, especially among contact lens users. Nanoparticles have been already included in several novel therapies against bacteria, viruses, fungi, and protist. However, their anti-amoebic potential has not been fully tested yet. The aim of this study was to assess silver nanoparticles (AgNPs) and platinum nanoparticles (PtNPs) anti-amoebic activity and influence on the amoebae adhesion to the surface of four different groups of contact lenses-classified according to the Food and Drugs Administration (FDA) guidelines. The obtained results show that both tested nanoparticles were effective against Acanthamoeba trophozoites and decreased the amoebae adhesion to the contact lens surface. AgNPs showed better anti-amoebic activity to cytotoxicity dependence and reduced amoebae adhesion in a wider spectrum of the tested contact lenses. Our studies also confirmed that ionization next to hydration of the contact lens material is a crucial parameter influencing the Acanthamoeba adhesion to the contact lens surface. In conclusion, silver nanoparticles might be considered as a novel preventive agent against Acanthamoeba keratitis infection.

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