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1.
J Cheminform ; 16(1): 84, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39049122

RESUMO

It is well-accepted that knowledge of a small molecule's target can accelerate optimization. Although chemogenomic databases are helpful resources for predicting or finding compound interaction partners, they tend to be limited and poorly annotated. Furthermore, unlike genes, compound identifiers are often not standardized, and many synonyms may exist, especially in the biological literature, making batch analysis of compounds difficult. Here, we constructed an open-source annotation and target hypothesis prediction tool that explores some of the largest chemical and biological databases, mining these for both common name, synonyms, and structurally similar molecules. We used this Chemical Analysis and Clustering for Target Identification (CACTI) tool to analyze the Pathogen Box collection, an open-source set of 400 drug-like compounds active against a variety of microbial pathogens. Our analysis resulted in 4,315 new synonyms, 35,963 pieces of new information and target prediction hints for 58 members.Scientific contributionsWith the employment of this tool, a comprehensive report with known evidence, close analogs and drug-target prediction can be obtained for large-scale chemical libraries that will facilitate their evaluation and future target validation and optimization efforts.

2.
Microbiol Spectr ; 12(4): e0414223, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38421191

RESUMO

In an effort to identify novel compounds with potent inhibition against Toxoplasma gondii, a phenotypic screen was performed utilizing a library of 683 pure compounds derived primarily from terrestrial and marine fungi. An initial screen with a fixed concentration of 5 µM yielded 91 hits with inhibition comparable to an equal concentration of artemisinin. These compounds were then triaged based on known biological and chemical concerns and liabilities. From these, 49 prioritized compounds were tested in a dose response format with T. gondii and human foreskin fibroblasts (HFFs) for cytotoxicity. Ten compounds were identified with an IC50 less than 150 nM and a selectivity index (SI) greater than 100. An additional eight compounds demonstrated submicromolar IC50 and SI values equal to or greater than 35. While the majority of these scaffolds have been previously implicated against apicomplexan parasites, their activities in T. gondii were largely unknown. Herein, we report the T. gondii activity of these compounds with chemotypes including xanthoquinodins, peptaibols, heptelidic acid analogs, and fumagillin analogs, with multiple compounds demonstrating exceptional potency in T. gondii and limited toxicity to HFFs at the highest concentrations tested. IMPORTANCE: Current therapeutics for treating toxoplasmosis remain insufficient, demonstrating high cytotoxicity, poor bioavailability, limited efficacy, and drug resistance. Additional research is needed to develop novel compounds with high efficacy and low cytotoxicity. The success of artemisinin and other natural products in treating malaria highlights the potential of natural products as anti-protozoan therapeutics. However, the exploration of natural products in T. gondii drug discovery has been less comprehensive, leaving untapped potential. By leveraging the resources available for the malaria drug discovery campaign, we conducted a phenotypic screen utilizing a set of natural products previously screened against Plasmodium falciparum. Our study revealed 18 compounds with high potency and low cytotoxicity in T. gondii, including four novel scaffolds with no previously reported activity in T. gondii. These new scaffolds may serve as starting points for the development of toxoplasmosis therapeutics but could also serve as tool compounds for target identification studies using chemogenomic approach.


Assuntos
Antiprotozoários , Artemisininas , Produtos Biológicos , Malária , Toxoplasma , Toxoplasmose , Humanos , Antiprotozoários/farmacologia , Produtos Biológicos/farmacologia , Artemisininas/farmacologia
3.
Cell Chem Biol ; 30(5): 486-498.e7, 2023 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-37172592

RESUMO

Chemical genetic approaches have had a transformative impact on discovery of drug targets for malaria but have primarily been used for parasite targets. To identify human pathways required for intrahepatic development of parasite, we implemented multiplex cytological profiling of malaria infected hepatocytes treated with liver stage active compounds. Some compounds, including MMV1088447 and MMV1346624, exhibited profiles similar to cells treated with nuclear hormone receptor (NHR) agonist/antagonists. siRNAs targeting human NHRs, or their signaling partners identified eight genes that were critical for Plasmodium berghei infection. Knockdown of NR1D2, a host NHR, significantly impaired parasite growth by downregulation of host lipid metabolism. Importantly, treatment with MMV1088447 and MMV1346624 but not other antimalarials, phenocopied the lipid metabolism defect of NR1D2 knockdown. Our data underlines the use of high-content imaging for host-cellular pathway deconvolution, highlights host lipid metabolism as a drug-able human pathway and provides new chemical biology tools for studying host-parasite interactions.


Assuntos
Malária , Parasitos , Animais , Humanos , Hepatócitos/metabolismo , Fígado/metabolismo , Malária/tratamento farmacológico , Malária/metabolismo , Plasmodium berghei/genética
4.
Br J Pharmacol ; 180(15): 1899-1929, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37197802

RESUMO

Antimalarial drug discovery has until recently been driven by high-throughput phenotypic cellular screening, allowing millions of compounds to be assayed and delivering clinical drug candidates. In this review, we will focus on target-based approaches, describing recent advances in our understanding of druggable targets in the malaria parasite. Targeting multiple stages of the Plasmodium lifecycle, rather than just the clinically symptomatic asexual blood stage, has become a requirement for new antimalarial medicines, and we link pharmacological data clearly to the parasite stages to which it applies. Finally, we highlight the IUPHAR/MMV Guide to MALARIA PHARMACOLOGY, a web resource developed for the malaria research community that provides open and optimized access to published data on malaria pharmacology.


Assuntos
Antimaláricos , Malária , Humanos , Malária/tratamento farmacológico , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Descoberta de Drogas , Ensaios de Triagem em Larga Escala
5.
Commun Biol ; 5(1): 128, 2022 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-35149760

RESUMO

In vitro evolution and whole genome analysis were used to comprehensively identify the genetic determinants of chemical resistance in Saccharomyces cerevisiae. Sequence analysis identified many genes contributing to the resistance phenotype as well as numerous amino acids in potential targets that may play a role in compound binding. Our work shows that compound-target pairs can be conserved across multiple species. The set of 25 most frequently mutated genes was enriched for transcription factors, and for almost 25 percent of the compounds, resistance was mediated by one of 100 independently derived, gain-of-function SNVs found in a 170 amino acid domain in the two Zn2C6 transcription factors YRR1 and YRM1 (p < 1 × 10-100). This remarkable enrichment for transcription factors as drug resistance genes highlights their important role in the evolution of antifungal xenobiotic resistance and underscores the challenge to develop antifungal treatments that maintain potency.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Regulação Fúngica da Expressão Gênica , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/metabolismo , Xenobióticos/metabolismo , Xenobióticos/farmacologia
6.
Trends Parasitol ; 37(6): 493-507, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33648890

RESUMO

The Malaria Drug Accelerator (MalDA) is a consortium of 15 leading scientific laboratories. The aim of MalDA is to improve and accelerate the early antimalarial drug discovery process by identifying new, essential, druggable targets. In addition, it seeks to produce early lead inhibitors that may be advanced into drug candidates suitable for preclinical development and subsequent clinical testing in humans. By sharing resources, including expertise, knowledge, materials, and reagents, the consortium strives to eliminate the structural barriers often encountered in the drug discovery process. Here we discuss the mission of the consortium and its scientific achievements, including the identification of new chemically and biologically validated targets, as well as future scientific directions.


Assuntos
Antimaláricos/uso terapêutico , Descoberta de Drogas , Malária/tratamento farmacológico , Antimaláricos/farmacologia , Plasmodium/efeitos dos fármacos , Tempo
7.
Beilstein J Org Chem ; 16: 2645-2662, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33178355

RESUMO

Systems glycobiology aims to provide models and analysis tools that account for the biosynthesis, regulation, and interactions with glycoconjugates. To facilitate these methods, there is a need for a clear glycan representation accessible to both computers and humans. Linear Code, a linearized and readily parsable glycan structure representation, is such a language. For this reason, Linear Code was adapted to represent reaction rules, but the syntax has drifted from its original description to accommodate new and originally unforeseen challenges. Here, we delineate the consensuses and inconsistencies that have arisen through this adaptation. We recommend options for a consensus-based extension of Linear Code that can be used for reaction rule specification going forward. Through this extension and specification of Linear Code to reaction rules, we aim to minimize inconsistent symbology thereby making glycan database queries easier. With a clear guide for generating reaction rule descriptions, glycan synthesis models will be more interoperable and reproducible thereby moving glycoinformatics closer to compliance with FAIR standards. Here, we present Linear Code for Reaction Rules (LiCoRR), version 1.0, an unambiguous representation for describing glycosylation reactions in both literature and code.

8.
ACS Infect Dis ; 6(4): 613-628, 2020 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-32078764

RESUMO

Most phenotypic screens aiming to discover new antimalarial chemotypes begin with low cost, high-throughput tests against the asexual blood stage (ABS) of the malaria parasite life cycle. Compounds active against the ABS are then sequentially tested in more difficult assays that predict whether a compound has other beneficial attributes. Although applying this strategy to new chemical libraries may yield new leads, repeated iterations may lead to diminishing returns and the rediscovery of chemotypes hitting well-known targets. Here, we adopted a different strategy to find starting points, testing ∼70,000 open source small molecules from the Global Health Chemical Diversity Library for activity against the liver stage, mature sexual stage, and asexual blood stage malaria parasites in parallel. In addition, instead of using an asexual assay that measures accumulated parasite DNA in the presence of compound (SYBR green), a real time luciferase-dependent parasite viability assay was used that distinguishes slow-acting (delayed death) from fast-acting compounds. Among 382 scaffolds with the activity confirmed by dose response (<10 µM), we discovered 68 novel delayed-death, 84 liver stage, and 68 stage V gametocyte inhibitors as well. Although 89% of the evaluated compounds had activity in only a single life cycle stage, we discovered six potent (half-maximal inhibitory concentration of <1 µM) multistage scaffolds, including a novel cytochrome bc1 chemotype. Our data further show the luciferase-based assays have higher sensitivity. Chemoinformatic analysis of positive and negative compounds identified scaffold families with a strong enrichment for activity against specific or multiple stages.


Assuntos
Antimaláricos/isolamento & purificação , Descoberta de Drogas , Estágios do Ciclo de Vida/efeitos dos fármacos , Plasmodium falciparum/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/farmacologia , Antimaláricos/química , Antimaláricos/farmacologia , Quimioinformática/métodos , Avaliação Pré-Clínica de Medicamentos , Ensaios de Triagem em Larga Escala , Plasmodium falciparum/genética , Bibliotecas de Moléculas Pequenas/química
9.
Rev. argent. microbiol ; 50(2): 136-146, jun. 2018. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-977230

RESUMO

The aim of the present study was to gather information regarding the molecular epidemiology of Human papillomavirus (HPV) and related risk factors in a group of women with low- and high-grade cervical lesions and cancer from the coastal region of Ecuador. In addition, we studied the evolution of HPV variants from the most prevalent types and provided a temporal framework for their emergence, which may help to trace the source of dissemination within the region. We analyzed 166 samples, including 57 CIN1, 95 CIN2/3 and 14 cancer cases. HPV detection and typing was done by PCR-sequencing (MY09/MY11). HPV variants and estimation of the time to most recent common ancestor (tMRCA) was assessed through phylogeny and coalescence analysis. HPV DNA was found in 54.4% of CIN1, 74.7% of CIN2/3 and 78.6% of cancer samples. HPV16 (38.9%) and HPV58 (19.5%) were the most prevalent types. Risk factors for the development of cervical lesions/cancer were the following: three or more pregnancies (OR = 4.3), HPV infection (OR = 3.7 for high-risk types; OR = 3.5 for HPV16), among others. With regard to HPV evolution, HPV16 isolates belonged to lineages A (69%) and D (31%) whereas HPV58 isolates belonged only to lineage A. The period of emergence of HPV16 was in association with human populations (tMRCA = 91 052 years for HPV16A and 27000 years for HPV16D), whereas HPV58A preceded Homo sapiens evolution (322 257 years). This study provides novel data on HPV epidemiology and evolution in Ecuador, which will be fundamental in the vaccine era.


El objetivo del presente estudio fue aportar información sobre la epidemiología molecular del virus del papiloma humano (human papillomavirus [HPV]) y los factores de riesgo asociados al desarrollo de lesiones cervicales y cáncer en mujeres de la costa del Ecuador. Además, se estudiaron la evolución de las variantes de los HPV más prevalentes y el marco temporal de su emergencia, para ayudar a rastrear la fuente de dispersión en la región. Se analizaron 166 muestras, incluyendo 57 y 95 casos de neoplasia intraepitelial cervical tipo 1 (CIN1) y tipo 2/3 (CIN2/3), respectivamente, y 14 de casos de cáncer. La detección/tipificación de HPV se realizó por PCR-secuenciación (MY09/MY11). La caracterización de variantes y la datación del ancestro común más reciente (tMRCA) se realizaron mediante filogenia y coalescencia. Se encontró ADN de HPV en el 54,4% de las muestras de CIN1, el 74,7% de las muestras de CIN2/3 y el 78,6% de las muestras de cáncer. Los tipos HPV16 (38,9%) y HPV58 (19,5%) fueron los más frecuentes. Los factores de riesgo para el desarrollo de lesiones cervicales/cáncer fueron 3 o más embarazos (OR = 4,3) e infección por HPV (O = 3,7 para HPV de alto riesgo, OR = 3,5 para HPV16), entre otros. En cuanto a la evolución viral, los aislados del HPV16 pertenecían a los linajes A (69%) y D (31%), mientras que los aislados del HPV58 pertenecían únicamente al linaje A. El período de emergencia del HPV16 estuvo asociado a poblaciones humanas (tMRCA = 91.052 años para HPV16Ay 27.000 para HPV16D), mientras que el del HPV58A precedió a la evolución de Homo sapiens (322.257 años). Este estudio proporciona datos novedosos sobre la epidemiología y la evolución del HPV en Ecuador, los cuales serán fundamentales en la era de la vacuna.


Assuntos
Feminino , Humanos , Filogenia , Neoplasias do Colo do Útero , Epidemiologia Molecular , Infecções por Papillomavirus , Papillomaviridae , DNA Viral/análise , Neoplasias do Colo do Útero/virologia , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/epidemiologia , Equador/epidemiologia
10.
Health Promot Pract ; 19(6): 905-914, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29448812

RESUMO

Low parent engagement is frequently identified as a barrier to effective implementation of family-based childhood obesity prevention and control programs. A more nuanced understanding of factors affecting parent engagement is important for improving implementation and, ultimately, program efficacy. This qualitative study examined factors influencing parent engagement in a family-based childhood obesity prevention and control program. Semistructured interviews informed by the health belief model and the transtheoretical model were conducted with 22 predominantly Latina mothers following the scheduled conclusion of program activities. Spanish- and English-language interviews were transcribed, translated into English (if Spanish), coded, and summarized using established protocols. Differences between parents who attended at least two thirds of program activities and those who did not were examined. There were no significant demographic differences between parents who did and did not complete two thirds of program activities. Findings indicated that differences in parent engagement may be at least partially explained by differences in parental motivations for participating and in barriers and facilitators, such as children's level of support and enthusiasm for the program. Parents were highly satisfied with the program content and the community health workers who delivered the program. This study adds to emergent literature regarding parents' experiences in family-based childhood obesity prevention and control programs. Potential targets for improving program engagement are discussed.


Assuntos
Agentes Comunitários de Saúde/organização & administração , Promoção da Saúde/organização & administração , Pais/educação , Obesidade Infantil/prevenção & controle , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Motivação , Satisfação do Paciente , Avaliação de Programas e Projetos de Saúde , Pesquisa Qualitativa , Fatores Socioeconômicos
11.
Rev Argent Microbiol ; 50(2): 136-146, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29157596

RESUMO

The aim of the present study was to gather information regarding the molecular epidemiology of Human papillomavirus (HPV) and related risk factors in a group of women with low- and high-grade cervical lesions and cancer from the coastal region of Ecuador. In addition, we studied the evolution of HPV variants from the most prevalent types and provided a temporal framework for their emergence, which may help to trace the source of dissemination within the region. We analyzed 166 samples, including 57 CIN1, 95 CIN2/3 and 14 cancer cases. HPV detection and typing was done by PCR-sequencing (MY09/MY11). HPV variants and estimation of the time to most recent common ancestor (tMRCA) was assessed through phylogeny and coalescence analysis. HPV DNA was found in 54.4% of CIN1, 74.7% of CIN2/3 and 78.6% of cancer samples. HPV16 (38.9%) and HPV58 (19.5%) were the most prevalent types. Risk factors for the development of cervical lesions/cancer were the following: three or more pregnancies (OR=4.3), HPV infection (OR=3.7 for high-risk types; OR=3.5 for HPV16), among others. With regard to HPV evolution, HPV16 isolates belonged to lineages A (69%) and D (31%) whereas HPV58 isolates belonged only to lineage A. The period of emergence of HPV16 was in association with human populations (tMRCA=91052 years for HPV16A and 27000 years for HPV16D), whereas HPV58A preceded Homo sapiens evolution (322257 years). This study provides novel data on HPV epidemiology and evolution in Ecuador, which will be fundamental in the vaccine era.


Assuntos
Epidemiologia Molecular , Infecções por Papillomavirus , Filogenia , Neoplasias do Colo do Útero , DNA Viral/análise , Equador/epidemiologia , Feminino , Humanos , Papillomaviridae , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/genética , Neoplasias do Colo do Útero/virologia
12.
Reprod Biol ; 15(2): 106-12, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26051459

RESUMO

To develop techniques for seedling production of yellowfin tuna, the behavior of primordial germ cells (PGCs) and gonadogenesis were examined at 1-30 days post hatching (dph) using morphometric analysis, histological examination, and in situ hybridization. Immediately after hatching, PGCs were located on the dorsal side of the posterior end of the rectum under the peritoneum of the larvae, and at 3 dph they came into contact with stromal cells. PGCs and stromal cells gradually moved forward from the anus prior to 5 dph. At 7-10 dph, germ cells were surrounded by stromal cells and the gonadal primordia were formed. In individuals collected at 12 dph, PGCs were detected by in situ hybridization using a vasa mRNA probe that is a germ-cell-specific detection marker. The proliferation of germ cells in the gonadal primordia began at 7-10 dph. We observed double the number of germ cells at 30 dph (22 ± 3.2 cells), compared to that at 1 dph (11 ± 2.1 cells). Therefore, based on our data and previous reports, the initial germ cell proliferation of yellowfin tuna is relatively slower than that of other fish species.


Assuntos
Oogênese , Óvulo/citologia , Desenvolvimento Sexual , Espermatogênese , Espermatozoides/citologia , Atum/crescimento & desenvolvimento , Animais , Aquicultura , Biomarcadores/metabolismo , Proliferação de Células , Feminino , Hibridização In Situ/veterinária , Masculino , Óvulo/metabolismo , Panamá , Espermatozoides/metabolismo , Células Estromais/citologia , Células Estromais/metabolismo , Atum/anatomia & histologia , Atum/metabolismo
13.
Dairy Sci Technol ; 92(2): 121-132, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22662290

RESUMO

Milk processing industries and distributors have problems with adulteration of liquid milk by the addition of bovine cheese whey. Recently, the detection of fraudulent manipulation of milk with whey has focused on the identification of glycomacropeptide (GMP). Current non-immunological methods to detect GMP in dairy products are expensive and time-consuming or have low sensitivity. In this study, a novel sandwich enzyme-linked immunosorbent assay (ELISA) for the detection and quantification of whey in raw milk was developed, using a polyclonal rabbit anti-GMP antibody. Calibration curves were constructed by analyzing raw milk standards containing different known concentrations of liquid cheese whey (0.02-20%). The method had a detection limit of 0.047% (v/v) and a quantification limit of 0.14% (v/v). The antibody showed high specificity and no cross-reaction with milk components (other than κ-casein) and was successful in detecting GMP in dairy commercial products. The recovery ratio was between 95.62% and 113.88% for all matrices tested. The intra-assay and interassay coefficients of variation were <6% and <7%, respectively. Finally, it can be stored for 3 months in the form of a ready-to-use kit, while maintaining its accuracy and reproducibility.

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