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1.
Dev Sci ; 26(2): e13296, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35737680

RESUMO

Infants' prelinguistic vocalizations reliably organize vocal turn-taking with social partners, creating opportunities for learning to produce the sound patterns of the ambient language. This social feedback loop supporting early vocal learning is well-documented, but its developmental origins have yet to be addressed. When do infants learn that their non-cry vocalizations influence others? To test developmental changes in infant vocal learning, we assessed the vocalizations of 2- and 5-month-old infants in a still-face interaction with an unfamiliar adult. During the still-face, infants who have learned the social efficacy of vocalizing increase their babbling rate. In addition, to assess the expectations for social responsiveness that infants build from their everyday experience, we recorded caregiver responsiveness to their infants' vocalizations during unstructured play. During the still-face, only 5-month-old infants showed an increase in vocalizing (a vocal extinction burst) indicating that they had learned to expect adult responses to their vocalizations. Caregiver responsiveness predicted the magnitude of the vocal extinction burst for 5-month-olds. Because 5-month-olds show a vocal extinction burst with unfamiliar adults, they must have generalized the social efficacy of their vocalizations beyond their familiar caregiver. Caregiver responsiveness to infant vocalizations during unstructured play was similar for 2- and 5-month-olds. Infants thus learn the social efficacy of their vocalizations between 2 and 5 months of age. During this time, infants build associations between their own non-cry sounds and the reactions of adults, which allows learning of the instrumental value of vocalizing.


Assuntos
Desenvolvimento da Linguagem , Voz , Adulto , Lactente , Humanos , Retroalimentação , Idioma , Cuidadores
2.
Am J Public Health ; 112(S7): S679-S689, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36179297

RESUMO

Objectives. To detail baseline drinking water sample lead concentrations and features of US state-level programs and policies to test school drinking water for lead in 7 states' operating programs between 2016 and 2018. Methods. We coded program and policy documents using structured content analysis protocols and analyzed state-provided data on lead concentration in drinking water samples collected in public schools during initial testing phases. Results. We analyzed data from 5688 public schools, representing 35% of eligible schools in 7 states. The number of samples per school varied. The proportion of schools identifying any sample lead concentration exceeding 5 parts per billion varied (13%-81%). Four states exceeded 20%. Other program features varied among states. Instances of lead above the state action level were identified in all states. Conclusions. In 2018, many US public school students attended schools in states without drinking water lead-testing programs. Testing all drinking water sources may be recommended. Public Health Implications. Initiating uniform school drinking water lead testing programs and surveillance over time could be used to reduce risk of lead exposure in drinking water. (Am J Public Health. 2022;112(S7):S679-S689. https://doi.org/10.2105/AJPH.2022.306961).


Assuntos
Água Potável , Humanos , Chumbo/análise , Políticas , Prevalência , Instituições Acadêmicas
3.
Br J Cancer ; 119(9): 1106-1117, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30318519

RESUMO

BACKGROUND: Adhesion-mediated activation of FAK/ERK signalling pathway, enabled by the formation of filopodial protrusions (FLP), has been shown to be an important event for triggering of dormancy-to-proliferation switch and metastatic outgrowth of breast cancer cells (BCC). We studied the role of actin-binding protein profilin1 (Pfn1) in these processes. METHODS: Quantitative immunohistochemistry (IHC) of BC tissue microarray (TMA) and survival analyses of curated transcriptome datasets of BC patients were performed to examine Pfn1's association with certain clinicopathological features. FLP formation and single cell outgrowth of BCC were assessed using a 3D matrigel culture that accurately predicts dormant vs metastatic outgrowth phenotypes of BCC in certain microenvironment. Gene expression studies were performed to identify potential biological pathways that are perturbed under Pfn1-depleted condition. RESULTS: Lower Pfn1 expression is correlated with lower nuclear grade of breast tumours and longer relapse-free survival of BC patients. Pfn1 depletion leads to defects in FLP and outgrowth of BCC but without impairing either FAK or ERK activation. Guided by transcriptome analyses, we further showed that Pfn1 depletion is associated with prominent SMAD3 upregulation. Although knockdown and overexpression experiments revealed that SMAD3 has an inhibitory effect on the outgrowth of breast cancer cells, SMAD3 knockdown alone was not sufficient to enhance the outgrowth potential of Pfn1-depleted BCC suggesting that other proliferation-regulatory pathways in conjunction with SMAD3 upregulation may underlie the outgrowth-deficient phenotype of BCC cells upon depletion of Pfn1. CONCLUSION: Overall, these data suggest that Pfn1 may be a novel biomarker for BC recurrence and a possible target to reduce metastatic outgrowth of BCC.


Assuntos
Neoplasias da Mama/patologia , Técnicas de Cultura de Células/métodos , Profilinas/deficiência , Proteína Smad3/genética , Regulação para Cima , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Gradação de Tumores , Prognóstico , Transdução de Sinais , Análise de Sobrevida , Análise Serial de Tecidos , Microambiente Tumoral
4.
Molecules ; 23(7)2018 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-29997348

RESUMO

Zebrafish is the preferred vertebrate model for high throughput chemical screens to discover modulators of complex biological pathways. We adapted a transgenic zebrafish line, Tg(dusp6:EGFP), which reports on fibroblast growth factor (Fgf)/Ras/Mapk activity, into a quantitative, high-content chemical screen to identify novel Fgf hyperactivators as chemical probes for zebrafish heart development and regeneration. We screened 10,000 compounds from the TimTec ActiProbe library, and identified several structurally distinct classes of molecules that enhanced Fgf/Ras/Mapk signaling. We chose three agents-ST020101, ST011282, and ST006994-for confirmatory and functional studies based on potency, repeatability with repurchased material, favorable whole organism toxicity, and evidence of structure⁻activity relationships. Functional follow-up assays confirmed that all three compounds induced the expression of Fgf target genes during zebrafish embryonic development. Moreover, these compounds increased cardiac progenitor populations by effecting a fate change from endothelial to cardiac progenitors that translated into increased numbers of cardiomyocytes. Interestingly, ST006994 augmented Fgf/Ras/Mapk signaling without increasing Erk phosphorylation, suggesting a molecular mechanism of action downstream of Erk. We posit that the ST006994 pharmacophore could become a unique chemical probe to uncover novel mechanisms of Fgf signaling during heart development and regeneration downstream of the Mapk signaling node.


Assuntos
Coração/embriologia , Ensaios de Triagem em Larga Escala/métodos , Sistema de Sinalização das MAP Quinases , Sondas Moleculares/química , Bibliotecas de Moléculas Pequenas/farmacologia , Peixe-Zebra/embriologia , Proteínas ras/metabolismo , Animais , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Coração/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Tamanho do Órgão/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/química
5.
J Pharmacol Exp Ther ; 361(1): 39-50, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28154014

RESUMO

Dual specificity mitogen-activated protein kinase (MAPK) phosphatases [dual specificity phosphatase/MAP kinase phosphatase (DUSP-MKP)] have been hypothesized to maintain cancer cell survival by buffering excessive MAPK signaling caused by upstream activating oncogenic products. A large and diverse body of literature suggests that genetic depletion of DUSP-MKPs can reduce tumorigenicity, suggesting that hyperactivating MAPK signaling by DUSP-MKP inhibitors could be a novel strategy to selectively affect the transformed phenotype. Through in vivo structure-activity relationship studies in transgenic zebrafish we recently identified a hyperactivator of fibroblast growth factor signaling [(E)-2-benzylidene-5-bromo-3-(cyclohexylamino)-2,3-dihydro-1H-inden-1-one (BCI-215)] that is devoid of developmental toxicity and restores defective MAPK activity caused by overexpression of DUSP1 and DUSP6 in mammalian cells. Here, we hypothesized that BCI-215 could selectively affect survival of transformed cells. In MDA-MB-231 human breast cancer cells, BCI-215 inhibited cell motility, caused apoptosis but not primary necrosis, and sensitized cells to lymphokine-activated killer cell activity. Mechanistically, BCI-215 induced rapid and sustained phosphorylation of extracellular signal-regulated kinase (ERK), p38, and c-Jun N-terminal kinase (JNK) in the absence of reactive oxygen species, and its toxicity was partially rescued by inhibition of p38 but not JNK or ERK. BCI-215 also hyperactivated MKK4/SEK1, suggesting activation of stress responses. Kinase phosphorylation profiling documented BCI-215 selectively activated MAPKs and their downstream substrates, but not receptor tyrosine kinases, SRC family kinases, AKT, mTOR, or DNA damage pathways. Our findings support the hypothesis that BCI-215 causes selective cancer cell cytotoxicity in part through non-redox-mediated activation of MAPK signaling, and the findings also identify an intersection with immune cell killing that is worthy of further exploration.


Assuntos
Neoplasias da Mama/metabolismo , Inibidores Enzimáticos/farmacologia , Células Matadoras Ativadas por Linfocina/efeitos dos fármacos , Células Matadoras Ativadas por Linfocina/metabolismo , Fosfatases da Proteína Quinase Ativada por Mitógeno/antagonistas & inibidores , Fosfatases da Proteína Quinase Ativada por Mitógeno/metabolismo , Animais , Animais Geneticamente Modificados , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/imunologia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/uso terapêutico , Feminino , Células HeLa , Hepatócitos/efeitos dos fármacos , Hepatócitos/imunologia , Hepatócitos/metabolismo , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases JNK Ativadas por Mitógeno/imunologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Células Matadoras Ativadas por Linfocina/imunologia , Fosfatases da Proteína Quinase Ativada por Mitógeno/imunologia , Ratos , Peixe-Zebra
6.
J Biol Chem ; 288(50): 35769-80, 2013 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-24174532

RESUMO

Autophagy can be activated via MTORC1 down-regulation by amino acid deprivation and by certain chemicals such as rapamycin, torin, and niclosamide. Lysosome is the degrading machine for autophagy but has also been linked to MTORC1 activation through the Rag/RRAG GTPase pathway. This association raises the question of whether lysosome can be involved in the initiation of autophagy. Toward this end, we found that niclosamide, an MTORC1 inhibitor, was able to inhibit lysosome degradation and increase lysosomal permeability. Niclosamide was ineffective in inhibiting MTORC1 in cells expressing constitutively activated Rag proteins, suggesting that its inhibitory effects were targeted to the Rag-MTORC1 signaling system. This places niclosamide in the same category of bafilomycin A1 and concanamycin A, inhibitors of the vacuolar H(+)-ATPase, for its dependence on Rag GTPase in suppression of MTORC1. Surprisingly, classical lysosome inhibitors such as chloroquine, E64D, and pepstatin A were also able to inhibit MTORC1 in a Rag-dependent manner. These lysosome inhibitors were able to activate early autophagy events represented by ATG16L1 and ATG12 puncta formation. Our work established a link between the functional status of the lysosome in general to the Rag-MTORC1 signaling axis and autophagy activation. Thus, the lysosome is not only required for autophagic degradation but also affects autophagy activation. Lysosome inhibitors can have a dual effect in suppressing autophagy degradation and in initiating autophagy.


Assuntos
Autofagia/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Retroalimentação Fisiológica/efeitos dos fármacos , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Complexos Multiproteicos/metabolismo , Niclosamida/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Linhagem Celular , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Complexos Multiproteicos/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/antagonistas & inibidores
7.
Chembiochem ; 15(10): 1436-45, 2014 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-24909879

RESUMO

Dual specificity phosphatase 6 (DUSP6) functions as a feedback attenuator of fibroblast growth factor signaling during development. In vitro high throughput chemical screening attempts to discover DUSP6 inhibitors have yielded limited success. However, in vivo whole-organism screens of zebrafish identified compound 1 (BCI) as an allosteric inhibitor of DUSP6. Here we designed and synthesized a panel of analogues to define the structure-activity relationship (SAR) of DUSP6 inhibition. In vivo high-content analysis in transgenic zebrafish, coupled with cell-based chemical complementation assays, identified structural features of the pharmacophore of 1 that were essential for biological activity. In vitro assays of DUSP hyperactivation corroborated the results from in vivo and cellular SAR. The results reinforce the notion that DUSPs are druggable through allosteric mechanisms and illustrate the utility of zebrafish as a model organism for in vivo SAR analyses.


Assuntos
Fosfatase 6 de Especificidade Dupla/antagonistas & inibidores , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Indenos/química , Indenos/farmacologia , Regulação Alostérica , Animais , Desenho de Fármacos , Fosfatase 6 de Especificidade Dupla/metabolismo , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Modelos Moleculares , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade , Peixe-Zebra/embriologia
8.
Antimicrob Agents Chemother ; 57(9): 4343-8, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23817384

RESUMO

Human cytomegalovirus (HCMV) is a widespread pathogen in the human population, affecting many immunologically immature and immunocompromised patients, and can result in severe complications, such as interstitial pneumonia and mental retardation. Current chemotherapies for the treatment of HCMV infections include ganciclovir (GCV), foscarnet, and cidofovir. However, the high incidences of adverse effects (neutropenia and nephrotoxicity) limit the use of these drugs. Cyclopropavir (CPV), a guanosine nucleoside analog, is 10-fold more active against HCMV than GCV (50% effective concentrations [EC50s] = 0.46 and 4.1 µM, respectively). We hypothesize that the mechanism of action of CPV is similar to that of GCV: phosphorylation to a monophosphate by viral pUL97 protein kinase with further phosphorylation to a triphosphate by endogenous kinases, resulting in inhibition of viral DNA synthesis. To test this hypothesis, we isolated a CPV-resistant virus, sequenced its genome, and discovered that bp 498 of UL97 was deleted. This mutation caused a frameshift in UL97 resulting in a truncated protein that lacks a kinase domain. To determine if this base pair deletion was responsible for drug resistance, the mutation was engineered into the wild-type viral genome, which was then exposed to increasing concentrations of CPV. The results demonstrate that the engineered virus was approximately 72-fold more resistant to CPV (EC50 = 25.8 ± 3.1 µM) than the wild-type virus (EC50 = 0.36 ± 0.11 µM). We conclude, therefore, that this mutation is sufficient for drug resistance and that pUL97 is involved in the mechanism of action of CPV.


Assuntos
Citomegalovirus/genética , Mutação da Fase de Leitura , Fases de Leitura Aberta , Proteínas Quinases/genética , Proteínas Virais/genética , Antivirais/farmacologia , Sequência de Bases , Células Cultivadas , Ciclopropanos/farmacologia , Citomegalovirus/efeitos dos fármacos , Citomegalovirus/crescimento & desenvolvimento , Farmacorresistência Viral/efeitos dos fármacos , Farmacorresistência Viral/genética , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/virologia , Ganciclovir/farmacologia , Guanina/análogos & derivados , Guanina/farmacologia , Humanos , Dados de Sequência Molecular , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases/metabolismo , Proteínas Virais/metabolismo
9.
Artigo em Inglês | MEDLINE | ID: mdl-37681836

RESUMO

The Water is K'é program was developed to increase water consumption and decrease consumption of sugar-sweetened beverages for young children and caregivers. The pilot program was successfully delivered by three Family and Child Education (FACE) programs on the Navajo Nation using a culturally centered curriculum between 2020 to 2022. The purpose of this research was to understand teacher and caregiver perspectives of program feasibility, acceptability, impact, and other factors influencing beverage behaviors due to the pilot program. Nine caregivers and teachers were interviewed between June 2022 and December 2022, and a study team of four, including three who self-identified as Navajo, analyzed the data using inductive thematic analysis and consensus building to agree on codes. Five themes emerged, including feasibility, acceptability, impact, suggestions for future use of the program, and external factors that influenced water consumption. The analysis showed stakeholders' strong approval for continuing the program based on impact and acceptability, and identified factors that promote the program and barriers that can be addressed to make the program sustainable. Overall, the Water is K'é program and staff overcame many challenges during the COVID-19 pandemic to support healthy behavior change that had a rippled influence among children, caregivers, teachers, and many others.


Assuntos
COVID-19 , Cuidadores , Criança , Humanos , Pré-Escolar , Pandemias , COVID-19/prevenção & controle , Bebidas , Água
10.
SLAS Discov ; 27(4): 229-241, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35058181

RESUMO

Mcm2-7 is the catalytic core of the eukaryotic replicative helicase, which together with CDC45 and the GINS complex unwind parental DNA to generate templates for DNA polymerase. Being a highly regulated and complex enzyme that operates via an incompletely understood multi-step mechanism, molecular probes of Mcm2-7 that interrogate specific mechanistic steps would be useful tools for research and potential future chemotherapy. Based upon a synthetic lethal approach, we previously developed a budding yeast multivariate cell-based high throughput screening (HTS) assay to identify putative Mcm inhibitors by their ability to specifically cause a growth defect in an mcm mutant relative to a wild-type strain[1]. Here, as proof of concept, we used this assay to screen a 1280-member compound library (LOPAC) for potential Mcm2-7 inhibitors. Primary screening and dose-dependent retesting identified twelve compounds from this library that specifically inhibited the growth of the Mcm mutant relative to the corresponding wild-type strain (0.9 % hit rate). Secondary assays were employed to rule out non-specific DNA damaging agents, establish direct protein-ligand interaction via biophysical methods, and verify in vivo DNA replication inhibition via fluorescence activated cell sorter analysis (FACS). We identified one agent (ß-carboline-3-carboxylic acid N-methylamide, CMA) that physically bound to the purified Mcm2-7 complex (Kdapp119 µM), and at slightly higher concentrations specifically blocked S-phase cell cycle progression of the wild-type strain. In total, identification of Mcm2-7 as a CMA target validates our synthetic lethal HTS assay paradigm as a tool to identify chemical probes for the Mcm2-7 replicative helicase.


Assuntos
Eucariotos , Ensaios de Triagem em Larga Escala , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Replicação do DNA , Eucariotos/metabolismo , Proteínas de Manutenção de Minicromossomo/genética , Proteínas de Manutenção de Minicromossomo/metabolismo
11.
Artigo em Inglês | MEDLINE | ID: mdl-35565014

RESUMO

Public schools in the U.S. generate about 14,500 tons of municipal solid waste daily, and approximately 42% of that is food packaging generated by school foodservice, contributing significantly to the global packaging waste crisis. This literature review summarizes methods used to evaluate food packaging waste in school foodservice. This review has two objectives: first, to understand which methodologies currently exist to evaluate food packaging waste generation and disposal in school foodservice; and second, to describe the creation of and share a practical standardized instrument to evaluate food packaging waste generation and disposal in school foodservice. A systematic review was conducted using the following search terms: solid waste, school, cafeteria and food packaging, waste, and school. The final review included 24 studies conducted in school environments (kindergarten through twelfth grade or college/university), 16 of which took place in the U.S. Food packaging waste evaluations included objective methods of waste audits, models, and secondary data as well as subjective methods of qualitative observations, questionnaires, interviews, and focus groups. Large variation exists in the settings, participants, designs, and methodologies for evaluating school foodservice packaging waste. Lack of standardization was observed even within each methodology (e.g., waste audit). A new instrument is proposed to support comprehensive and replicable data collection, to further the understanding of school foodservice food packaging waste in the U.S., and to reduce environmental harms.


Assuntos
Serviços de Alimentação , Eliminação de Resíduos , Embalagem de Alimentos , Humanos , Eliminação de Resíduos/métodos , Instituições Acadêmicas , Resíduos Sólidos , Inquéritos e Questionários
12.
Birth Defects Res C Embryo Today ; 93(3): 281-7, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21932436

RESUMO

Zebrafish have become an invaluable vertebrate animal model to interrogate small molecule libraries for modulators of complex biological pathways and phenotypes. We have recently described the implementation of a quantitative, high-content imaging assay in multi-well plates to analyze the effects of small molecules on Fibroblast Growth Factor (FGF) signaling in vivo. Here we have evaluated the capability of the assay to identify compounds that hyperactivate FGF signaling from a test cassette of agents with known biological activities. Using a transgenic zebrafish reporter line for FGF activity, we screened 1040 compounds from an annotated library of known bioactive agents, including FDA-approved drugs. The assay identified two molecules, 8-hydroxyquinoline sulfate and pyrithione zinc, that enhanced FGF signaling in specific areas of the brain. Subsequent studies revealed that both compounds specifically expanded FGF target gene expression. Furthermore, treatment of early stage embryos with either compound resulted in dorsalized phenotypes characteristic of hyperactivation of FGF signaling in early development. Documented activities for both agents included activation of extracellular signal-related kinase (ERK), consistent with FGF hyperactivation. To conclude, we demonstrate the power of automated quantitative high-content imaging to identify small molecule modulators of FGF.


Assuntos
Animais Geneticamente Modificados , Embrião não Mamífero/efeitos dos fármacos , Fatores de Crescimento de Fibroblastos/metabolismo , Ensaios de Triagem em Larga Escala , Preparações Farmacêuticas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Animais , Peixe-Zebra/embriologia
13.
SLAS Discov ; 26(8): 1029-1039, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34167376

RESUMO

Triose phosphate isomerase deficiency (TPI Df) is an untreatable, childhood-onset glycolytic enzymopathy. Patients typically present with frequent infections, anemia, and muscle weakness that quickly progresses with severe neuromusclar dysfunction requiring aided mobility and often respiratory support. Life expectancy after diagnosis is typically ~5 years. There are several described pathogenic mutations that encode functional proteins; however, these proteins, which include the protein resulting from the "common" TPIE105D mutation, are unstable due to active degradation by protein quality control (PQC) pathways. Previous work has shown that elevating mutant TPI levels by genetic or pharmacological intervention can ameliorate symptoms of TPI Df in fruit flies. To identify compounds that increase levels of mutant TPI, we have developed a human embryonic kidney (HEK) stable knock-in model expressing the common TPI Df protein fused with green fluorescent protein (HEK TPIE105D-GFP). To directly address the need for lead TPI Df therapeutics, these cells were developed into an optical drug discovery platform that was implemented for high-throughput screening (HTS) and validated in 3-day variability tests, meeting HTS standards. We initially used this assay to screen the 446-member National Institutes of Health (NIH) Clinical Collection and validated two of the hits in dose-response, by limited structure-activity relationship studies with a small number of analogs, and in an orthogonal, non-optical assay in patient fibroblasts. The data form the basis for a large-scale phenotypic screening effort to discover compounds that stabilize TPI as treatments for this devastating childhood disease.


Assuntos
Descoberta de Drogas/métodos , Estabilidade Enzimática/efeitos dos fármacos , Ensaios de Triagem em Larga Escala/métodos , Bibliotecas de Moléculas Pequenas , Triose-Fosfato Isomerase/química , Avaliação Pré-Clínica de Medicamentos/métodos , Genes Reporter , Células HEK293 , Humanos , Mutação , Triose-Fosfato Isomerase/antagonistas & inibidores , Triose-Fosfato Isomerase/deficiência , Triose-Fosfato Isomerase/genética
14.
J Pharmacol Exp Ther ; 332(3): 906-11, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20008956

RESUMO

Disorazoles are macrocyclic polyketides first isolated from the fermentation broth of the myxobacterium Sorangium cellulosum. Both the major fermentation product disorazole A(1) and its much rarer companion disorazole C(1) exhibit potent cytotoxic activity against many human tumor cells. Furthermore, the disorazoles appear to bind tubulin uniquely among known antimitotic agents, promoting apoptosis or premature senescence. It is uncertain what conveys tumor cell sensitivity to these complex natural products. Therefore, we generated and characterized human tumor cells resistant to disorazole C(1). Resistant cells proved exceedingly difficult to generate and required single step mutagenesis with chronic stepwise exposure to increasing concentrations of disorazole C(1). Compared with wild-type HeLa cells, disorazole C(1)-resistant HeLa/DZR cells were 34- and 8-fold resistant to disorazole C(1) and disorazole A(1) growth inhibition, respectively. HeLa/DZR cells were also remarkably cross-resistant to vinblastine (280-fold), paclitaxel (2400-fold), and doxorubicin (47-fold) but not cisplatin, suggesting a multidrug-resistant phenotype. Supporting this hypothesis, MCF7/MDR cells were 10-fold cross-resistant to disorazole C(1). HeLa/DZR disorazole resistance was not durable in the absence of chronic compound exposure. Verapamil reversed HeLa/DZR resistance to disorazole C(1) and disorazole A(1). Moreover, HeLa/DZR cells expressed elevated levels of the drug resistance ATP-binding cassette ABCB1 transporter. Loss of ABCB1 by incubation with short interfering RNA restored sensitivity to the disorazoles. Thus, the multidrug resistance transporter ABCB1 can affect the cytotoxicity of both disorazole C(1) and A(1). Disorazole C(1), however, retained activity against cells resistant against the clinically used microtubule-stabilizing agent epothilone B.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Macrolídeos/farmacologia , Oxazóis/farmacologia , Moduladores de Tubulina/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/biossíntese , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Proliferação de Células/efeitos dos fármacos , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Epotilonas/farmacologia , Humanos , RNA Interferente Pequeno/genética
15.
SLAS Discov ; 25(8): 939-949, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32349647

RESUMO

Autosomal dominant leukodystrophy (ADLD) is a fatal, progressive adult-onset disease characterized by widespread central nervous system (CNS) demyelination and significant morbidity. The late age of onset together with the relatively slow disease progression provides a large therapeutic window for the disorder. However, no treatment exists for ADLD, representing an urgent and unmet clinical need. We have previously shown that ADLD is caused by duplications of the lamin B1 gene causing increased expression of the lamin B1 protein, a major constituent of the nuclear lamina, and demonstrated that transgenic mice with oligodendrocyte-specific overexpression of lamin B1 exhibit temporal and histopathological features reminiscent of the human disease. As increased levels of lamin B1 are the causative event triggering ADLD, approaches aimed at reducing lamin B1 levels and associated functional consequences represent a promising strategy for discovery of small-molecule ADLD therapeutics. To this end, we have created an inducible cell culture model of lamin B1 overexpression and developed high-content analysis in connection with multivariate analysis to define, analyze, and quantify lamin B1 expression and its associated abnormal nuclear phenotype in mouse embryonic fibroblasts (MEFs). The assay has been optimized to meet high-throughput screening (HTS) criteria in multiday variability studies. To control for batch-to-batch variation in the primary MEFs, we have implemented a screening strategy that employs sentinel cells to avoid costly losses during HTS. We posit the assay will identify bona fide suppressors of lamin B1 pathophysiology as candidates for development into potential therapies for ADLD.


Assuntos
Doenças Desmielinizantes/tratamento farmacológico , Lamina Tipo B/genética , Doença de Pelizaeus-Merzbacher/tratamento farmacológico , Bibliotecas de Moléculas Pequenas/farmacologia , Adulto , Animais , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/genética , Sistema Nervoso Central/efeitos dos fármacos , Sistema Nervoso Central/patologia , Doenças Desmielinizantes/genética , Doenças Desmielinizantes/patologia , Fibroblastos/efeitos dos fármacos , Ensaios de Triagem em Larga Escala/métodos , Humanos , Camundongos , Doença de Pelizaeus-Merzbacher/genética , Doença de Pelizaeus-Merzbacher/patologia , Fenótipo , Cultura Primária de Células , Bibliotecas de Moléculas Pequenas/química
17.
Front Pediatr ; 5: 293, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29379779

RESUMO

INTRODUCTION: Ventricular septal defect (VSD) is the most common congenital heart defect, with larger VSDs typically being corrected with an open-heart surgery during infancy. Long-term consequences of a VSD-corrective surgery on stress systems of child and mother are still unknown. The aim of the present study is to investigate the associations of an early corrected VSD and diurnal cortisol release of child and mother. METHODS: 26 children (12 boys) between 6 and 9 years old, who underwent surgery for an isolated VSD within the first 3 years of life, and their mothers participated in the study. Their diurnal cortisol profiles were compared to a sex-, age-, and socioeconomic status-matched healthy control group. Within the VSD group, associations between cortisol and characteristics of surgery and hospitalization were investigated. Child and mother psychopathological symptoms were considered as a possible interfering mechanism of altered cortisol profiles. RESULTS: Diurnal cortisol profiles of children with an early corrected VSD did not differ from those of controls. However, mothers of affected children exhibited higher cortisol levels in the morning (p < 0.001, [Formula: see text]) and a steeper diurnal cortisol slope (p = 0.016, [Formula: see text]) than mothers of healthy children. CONCLUSION: Results indicate a favorable development of children with an early corrected VSD, in terms of comparable diurnal cortisol profiles with healthy controls, according to a comparable mother-rated psychopathology. Mothers of affected children reveal altered diurnal cortisol levels, without differences in self-rated psychopathology. This divergence should be clarified in future research.

18.
Am J Health Syst Pharm ; 72(15): 1279-84, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26195653

RESUMO

PURPOSE: Published evidence regarding the use of cannabis and cannabis derivatives by military veterans with posttraumatic stress disorder (PTSD) is reviewed. SUMMARY: When inhaled or delivered orally or transdermally, cannabinoids (the psychoactive components of unrefined marijuana and various derivative products) activate endogenous cannabinoid receptors, modulating neurotransmitter release and producing a wide range of central nervous system effects, including increased pleasure and alteration of memory processes. Those effects provide a pharmacologic rationale for the use of cannabinoids to manage the three core PTSD symptom clusters: reexperiencing, avoidance and numbing, and hyperarousal. A literature search identified 11 articles pertaining to cannabis use by military veterans who met standard diagnostic criteria for PTSD. Cross-sectional studies have found a direct correlation between more severe PTSD symptomatology and increased motivation to use cannabis for coping purposes, especially among patients with difficulties in emotional regulation or stress tolerance. Data from 4 small studies suggested that cannabinoid use was associated with global improvements in PTSD symptoms or amelioration of specific PTSD symptoms such as insomnia and nightmares. Large well-designed controlled trials are needed in order to better delineate the potential role of cannabinoids as an adjunct or alternative to conventional approaches to PTSD management. CONCLUSION: While further research into cannabinoid treatment effects on PTSD symptoms is required, the evaluated evidence indicates that substantial numbers of military veterans with PTSD use cannabis or derivative products to control PTSD symptoms, with some patients reporting benefits in terms of reduced anxiety and insomnia and improved coping ability.


Assuntos
Canabinoides/uso terapêutico , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Veteranos , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estados Unidos
19.
PLoS One ; 10(3): e0122083, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25894744

RESUMO

Autophagy is the process by which cytosolic components and organelles are delivered to the lysosome for degradation. Autophagy plays important roles in cellular homeostasis and disease pathogenesis. Small chemical molecules that can modulate autophagy activity may have pharmacological value for treating diseases. Using a GFP-LC3-based high content screening assay we identified a novel chemical that is able to modulate autophagy at both initiation and degradation levels. This molecule, termed as Autophagy Modulator with Dual Effect-1 (AMDE-1), triggered autophagy in an Atg5-dependent manner, recruiting Atg16 to the pre-autophagosomal site and causing LC3 lipidation. AMDE-1 induced autophagy through the activation of AMPK, which inactivated mTORC1 and activated ULK1. AMDE-1did not affect MAP kinase, JNK or oxidative stress signaling for autophagy induction. Surprisingly, treatment with AMDE-1 resulted in impairment in autophagic flux and inhibition of long-lived protein degradation. This inhibition was correlated with a reduction in lysosomal degradation capacity but not with autophagosome-lysosome fusion. Further analysis indicated that AMDE-1 caused a reduction in lysosome acidity and lysosomal proteolytic activity, suggesting that it suppressed general lysosome function. AMDE-1 thus also impaired endocytosis-mediated EGF receptor degradation. The dual effects of AMDE-1 on autophagy induction and lysosomal degradation suggested that its net effect would likely lead to autophagic stress and lysosome dysfunction, and therefore cell death. Indeed, AMDE-1 triggered necroptosis and was preferentially cytotoxic to cancer cells. In conclusion, this study identified a new class of autophagy modulators with dual effects, which can be explored for potential uses in cancer therapy.


Assuntos
Antineoplásicos/farmacologia , Autofagia/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Proteína 5 Relacionada à Autofagia , Proteína Homóloga à Proteína-1 Relacionada à Autofagia , Linhagem Celular Tumoral , Avaliação Pré-Clínica de Medicamentos , Ensaios de Triagem em Larga Escala , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina , Proteínas Associadas aos Microtúbulos/metabolismo , Complexos Multiproteicos/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo
20.
Eur J Med Chem ; 96: 504-18, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25951294

RESUMO

Tubulin-interacting agents, like vinca alkaloid and taxanes, play a fundamental role in cancer chemotherapy, making cellular microtubules (MT), one of the few validated anticancer targets. Cancer resistance to classical MT inhibitors has motivated the development of novel molecules with increased efficacy and lower toxicity. Aiming at designing structurally-simple inhibitors of MT assembly, we synthesized a series of thirty-one 3,4,5-trimethoxy-hydrazones and twenty-five derivatives or analogs. Docking simulations suggested that a representative N-acylhydrazone could adopt an appropriate stereochemistry inside the colchicine-binding domain of tubulin. Several of these compounds showed anti-leukemia effects in the nanomolar concentration range. Interference with MT polymerization was validated by the compounds' ability to inhibit MT assembly at the biochemical and cellular level. Selective toxicity investigations done with the most potent compound, a 3,4,5-trimethoxy-hydrazone with a 1-naphthyl group, showed remarkably selective toxicity against leukemia cells in comparison with stimulated normal lymphocytes, and no acute toxicity in vivo. Finally, this molecule was as active as vincristine in a murine model of human acute lymphoblastic leukemia at a weekly dose of 1 mg/kg.


Assuntos
Anisóis/farmacologia , Antineoplásicos/farmacologia , Hidrazonas/farmacologia , Microtúbulos/efeitos dos fármacos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Animais , Anisóis/síntese química , Anisóis/química , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Hidrazonas/síntese química , Hidrazonas/química , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Microtúbulos/metabolismo , Modelos Moleculares , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Relação Estrutura-Atividade , Tubulina (Proteína)/metabolismo , Células Tumorais Cultivadas
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