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1.
Nature ; 589(7842): 474-479, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33299186

RESUMO

The psychedelic alkaloid ibogaine has anti-addictive properties in both humans and animals1. Unlike most medications for the treatment of substance use disorders, anecdotal reports suggest that ibogaine has the potential to treat addiction to various substances, including opiates, alcohol and psychostimulants. The effects of ibogaine-like those of other psychedelic compounds-are long-lasting2, which has been attributed to its ability to modify addiction-related neural circuitry through the activation of neurotrophic factor signalling3,4. However, several safety concerns have hindered the clinical development of ibogaine, including its toxicity, hallucinogenic potential and tendency to induce cardiac arrhythmias. Here we apply the principles of function-oriented synthesis to identify the key structural elements of the potential therapeutic pharmacophore of ibogaine, and we use this information to engineer tabernanthalog-a water-soluble, non-hallucinogenic, non-toxic analogue of ibogaine that can be prepared in a single step. In rodents, tabernanthalog was found to promote structural neural plasticity, reduce alcohol- and heroin-seeking behaviour, and produce antidepressant-like effects. This work demonstrates that, through careful chemical design, it is possible to modify a psychedelic compound to produce a safer, non-hallucinogenic variant that has therapeutic potential.


Assuntos
Comportamento Aditivo/tratamento farmacológico , Desenho de Fármacos , Ibogaína/análogos & derivados , Ibogaína/efeitos adversos , Alcoolismo/tratamento farmacológico , Animais , Antidepressivos/farmacologia , Arritmias Cardíacas/induzido quimicamente , Técnicas de Química Sintética , Depressão/tratamento farmacológico , Modelos Animais de Doenças , Feminino , Alucinógenos/efeitos adversos , Dependência de Heroína/tratamento farmacológico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Plasticidade Neuronal/efeitos dos fármacos , Segurança do Paciente , Receptor 5-HT2A de Serotonina/metabolismo , Agonistas do Receptor 5-HT2 de Serotonina/farmacologia , Transtornos Relacionados ao Uso de Substâncias/tratamento farmacológico , Natação , Tabernaemontana/química
2.
Nat Chem Biol ; 12(7): 552-8, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27239788

RESUMO

Humans and many animals show 'freezing' behavior in response to threatening stimuli. In humans, inappropriate threat responses are fundamental characteristics of several mental illnesses. To identify small molecules that modulate threat responses, we developed a high-throughput behavioral assay in zebrafish (Danio rerio) and evaluated 10,000 compounds for their effects on freezing behavior. We found three classes of compounds that switch the threat response from freezing to escape-like behavior. We then screened these for binding activity across 45 candidate targets. Using target profile clustering, we identified the sigma-1 (σ1) receptor as having a role in the mechanism of behavioral switching and confirmed that known σ1 ligands also disrupt freezing behavior. Furthermore, mutation of the gene encoding σ1 prevented the behavioral effect of escape-inducing compounds. One compound, which we call finazine, potently bound mammalian σ1 and altered threat-response behavior in mice. Thus, pharmacological and genetic interrogation of the freezing response revealed σ1 as a mediator of threat responses in vertebrates.


Assuntos
Reação de Fuga/efeitos dos fármacos , Reação de Congelamento Cataléptica/efeitos dos fármacos , Larva/efeitos dos fármacos , Receptores sigma/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologia , Peixe-Zebra , Anilidas/química , Anilidas/metabolismo , Anilidas/farmacologia , Animais , Reação de Fuga/efeitos da radiação , Reação de Congelamento Cataléptica/efeitos da radiação , Ensaios de Triagem em Larga Escala , Larva/efeitos da radiação , Ligantes , Luz , Camundongos , Estrutura Molecular , Piperazinas/química , Piperazinas/metabolismo , Piperazinas/farmacologia , Receptores sigma/genética , Bibliotecas de Moléculas Pequenas/química , Peixe-Zebra/crescimento & desenvolvimento , Receptor Sigma-1
3.
Nat Chem Biol ; 12(7): 559-66, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27239787

RESUMO

Many psychiatric drugs act on multiple targets and therefore require screening assays that encompass a wide target space. With sufficiently rich phenotyping and a large sampling of compounds, it should be possible to identify compounds with desired mechanisms of action on the basis of behavioral profiles alone. Although zebrafish (Danio rerio) behavior has been used to rapidly identify neuroactive compounds, it is not clear what types of behavioral assays would be necessary to identify multitarget compounds such as antipsychotics. Here we developed a battery of behavioral assays in larval zebrafish to determine whether behavioral profiles can provide sufficient phenotypic resolution to identify and classify psychiatric drugs. Using the antipsychotic drug haloperidol as a test case, we found that behavioral profiles of haloperidol-treated zebrafish could be used to identify previously uncharacterized compounds with desired antipsychotic-like activities and multitarget mechanisms of action.


Assuntos
Antipsicóticos/análise , Antipsicóticos/farmacologia , Comportamento Animal/efeitos dos fármacos , Peixe-Zebra , Animais , Antipsicóticos/química , Larva/efeitos dos fármacos , Camundongos , Estrutura Molecular , Peixe-Zebra/crescimento & desenvolvimento
4.
Mol Cell ; 31(4): 586-597, 2008 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-18722182

RESUMO

The dynamin family of GTPases regulate mitochondrial fission and fusion processes and have been implicated in controlling the release of caspase activators from mitochondria during apoptosis. Here we report that profusion genes fzo-1 and eat-3 or the profission gene drp-1 are not required for apoptosis activation in C. elegans. However, minor proapoptotic roles for drp-1 and fis-2, a homolog of human Fis1, are revealed in sensitized genetic backgrounds. drp-1 and fis-2 function independent of one another and the Bcl-2 homolog CED-9 and downstream of the CED-3 caspase to promote elimination of mitochondria in dying cells, an event that could facilitate cell-death execution. Interestingly, CED-3 can cleave DRP-1, which appears to be important for DRP-1's proapoptotic function, but not its mitochondria fission function. Our findings demonstrate that mitochondria dynamics do not regulate apoptosis activation in C. elegans and reveal distinct roles for drp-1 and fis-2 as mediators of cell-death execution downstream of caspase activation.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/citologia , Caspases/metabolismo , Animais , Caenorhabditis elegans/ultraestrutura , Morte Celular , Sobrevivência Celular , DNA de Helmintos/metabolismo , Embrião não Mamífero/citologia , Embrião não Mamífero/ultraestrutura , Mitocôndrias/ultraestrutura , Mutação/genética , Faringe/citologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
5.
Nat Chem Biol ; 9(4): 257-63, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23396078

RESUMO

Optogenetics is a powerful research tool because it enables high-resolution optical control of neuronal activity. However, current optogenetic approaches are limited to transgenic systems expressing microbial opsins and other exogenous photoreceptors. Here, we identify optovin, a small molecule that enables repeated photoactivation of motor behaviors in wild-type zebrafish and mice. To our surprise, optovin's behavioral effects are not visually mediated. Rather, photodetection is performed by sensory neurons expressing the cation channel TRPA1. TRPA1 is both necessary and sufficient for the optovin response. Optovin activates human TRPA1 via structure-dependent photochemical reactions with redox-sensitive cysteine residues. In animals with severed spinal cords, optovin treatment enables control of motor activity in the paralyzed extremities by localized illumination. These studies identify a light-based strategy for controlling endogenous TRPA1 receptors in vivo, with potential clinical and research applications in nontransgenic animals, including humans.


Assuntos
Canais Iônicos/metabolismo , Transdução de Sinal Luminoso/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Processos Fotoquímicos/efeitos dos fármacos , Células Receptoras Sensoriais/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/farmacologia , Proteínas de Peixe-Zebra/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/efeitos da radiação , Cisteína/química , Cisteína/metabolismo , Transporte de Elétrons/efeitos dos fármacos , Transporte de Elétrons/efeitos da radiação , Embrião não Mamífero , Humanos , Canais Iônicos/agonistas , Canais Iônicos/genética , Lasers , Luz , Transdução de Sinal Luminoso/efeitos da radiação , Camundongos , Atividade Motora/fisiologia , Atividade Motora/efeitos da radiação , Mutação , Oxirredução , Processos Fotoquímicos/efeitos da radiação , Piperazinas/farmacologia , Isoformas de Proteínas/agonistas , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Células Receptoras Sensoriais/fisiologia , Células Receptoras Sensoriais/efeitos da radiação , Relação Estrutura-Atividade , Canal de Cátion TRPA1 , Canais de Potencial de Receptor Transitório , Peixe-Zebra , Proteínas de Peixe-Zebra/agonistas , Proteínas de Peixe-Zebra/genética
6.
J Neurosci ; 33(9): 3834-43, 2013 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-23447595

RESUMO

Nonvisual photosensation enables animals to sense light without sight. However, the cellular and molecular mechanisms of nonvisual photobehaviors are poorly understood, especially in vertebrate animals. Here, we describe the photomotor response (PMR), a robust and reproducible series of motor behaviors in zebrafish that is elicited by visual wavelengths of light but does not require the eyes, pineal gland, or other canonical deep-brain photoreceptive organs. Unlike the relatively slow effects of canonical nonvisual pathways, motor circuits are strongly and quickly (seconds) recruited during the PMR behavior. We find that the hindbrain is both necessary and sufficient to drive these behaviors. Using in vivo calcium imaging, we identify a discrete set of neurons within the hindbrain whose responses to light mirror the PMR behavior. Pharmacological inhibition of the visual cycle blocks PMR behaviors, suggesting that opsin-based photoreceptors control this behavior. These data represent the first known light-sensing circuit in the vertebrate hindbrain.


Assuntos
Movimento/fisiologia , Opsinas/metabolismo , Células Fotorreceptoras de Vertebrados/fisiologia , Rombencéfalo/citologia , Comportamento Estereotipado/fisiologia , Fatores Etários , Análise de Variância , Animais , Fenômenos Biomecânicos , Biofísica , Cálcio/metabolismo , Embrião não Mamífero , Feminino , Masculino , Microscopia Confocal , Morfolinos/farmacologia , Movimento/efeitos dos fármacos , Movimento/efeitos da radiação , Células Musculares/efeitos dos fármacos , Células Musculares/efeitos da radiação , Vias Neurais/efeitos dos fármacos , Vias Neurais/fisiologia , Vias Neurais/efeitos da radiação , Opsinas/química , Estimulação Luminosa , Células Fotorreceptoras de Vertebrados/efeitos dos fármacos , Células Fotorreceptoras de Vertebrados/efeitos da radiação , Rombencéfalo/fisiologia , Comportamento Estereotipado/efeitos dos fármacos , Comportamento Estereotipado/efeitos da radiação , Fatores de Tempo , Peixe-Zebra
7.
ACS Chem Neurosci ; 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39287508

RESUMO

A recently reported behavioral screen in larval zebrafish for phenocopiers of known anesthetics and associated drugs yielded an isoflavone. Related isoflavones have also been reported as GABAA potentiators. From this, we synthesized a small library of isoflavones and incorporated an in vivo phenotypic approach to perform structure-behavior relationship studies of the screening hit and related analogs via behavioral profiling, patch-clamp experiments, and whole brain imaging. This revealed that analogs effect a range of behavioral responses, including sedation with and without enhancing the acoustic startle response. Interestingly, a subset of compounds effect sedation and enhancement of motor responses to both acoustic and light stimuli. Patch clamp recordings of cells with a human GABAA receptor confirmed that behavior-modulating isoflavones modify the GABA signaling. To better understand these molecules' nuanced effects on behavior, we performed whole brain imaging to reveal that analogs differentially effect neuronal activity. These studies demonstrate a multimodal approach to assessing activities of neuroactives.

8.
Nat Chem Biol ; 8(2): 144-6, 2011 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-22179068

RESUMO

Target identification is a core challenge in chemical genetics. Here we use chemical similarity to computationally predict the targets of 586 compounds that were active in a zebrafish behavioral assay. Among 20 predictions tested, 11 compounds had activities ranging from 1 nM to 10,000 nM on the predicted targets. The roles of two of these targets were tested in the original zebrafish phenotype. Prediction of targets from chemotype is rapid and may be generally applicable.


Assuntos
Simulação por Computador , Avaliação Pré-Clínica de Medicamentos/métodos , Animais , Comportamento Animal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Fenótipo , Relação Estrutura-Atividade , Peixe-Zebra
9.
Nat Chem Biol ; 6(3): 231-237, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20081854

RESUMO

Neuroactive small molecules are indispensable tools for treating mental illnesses and dissecting nervous system function. However, it has been difficult to discover novel neuroactive drugs. Here, we describe a high-throughput, behavior-based approach to neuroactive small molecule discovery in the zebrafish. We used automated screening assays to evaluate thousands of chemical compounds and found that diverse classes of neuroactive molecules caused distinct patterns of behavior. These 'behavioral barcodes' can be used to rapidly identify new psychotropic chemicals and to predict their molecular targets. For example, we identified new acetylcholinesterase and monoamine oxidase inhibitors using phenotypic comparisons and computational techniques. By combining high-throughput screening technologies with behavioral phenotyping in vivo, behavior-based chemical screens can accelerate the pace of neuroactive drug discovery and provide small-molecule tools for understanding vertebrate behavior.

10.
Mol Reprod Dev ; 78(1): 22-32, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21268180

RESUMO

In vitro studies have suggested that the Cables1 gene regulates epithelial cell proliferation, whereas other studies suggest a role in promoting neural differentiation. In efforts to clarify the functions of Cables1 in vivo, we conducted gain- and loss-of-function studies targeting its ortholog (cables1) in the zebrafish embryo. Similar to rodents, zebrafish cables1 mRNA expression is detected most robustly in embryonic neural tissues. Antisense knockdown of cables1 leads to increased numbers of apoptotic cells, particularly in brain tissue, in addition to a distinct behavioral phenotype, characterized by hyperactivity in response to stimulation. Apoptosis and the behavioral abnormality could be rescued by co-expression of a morpholino-resistant cables1 construct. Suppression of p53 expression in cables1 morphants partially rescued both apoptosis and the behavioral phenotype, suggesting that the phenotype of cables1 morphants is due in part to p53-dependent apoptosis. Alterations in the expression patterns of several neural transcription factors were observed in cables1 morphants during early neurulation, suggesting that cables1 is required for early neural differentiation. Ectopic overexpression of cables1 strongly disrupted embryonic morphogenesis, while overexpression of a cables1 mutant lacking the C-terminal cyclin box had little effect, suggesting functional importance of the cyclin box. Lastly, marked reductions in p35, but not Cdk5, were observed in cables1 morphants. Collectively, these data suggest that cables1 is important for neural differentiation during embryogenesis, in a mechanism that likely involves interactions with the Cdk5/p35 kinase pathway.


Assuntos
Proteínas de Transporte/biossíntese , Ciclinas/biossíntese , Embrião não Mamífero/embriologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Sistema Nervoso/embriologia , Neurogênese/fisiologia , Fosfoproteínas/biossíntese , Proteínas de Peixe-Zebra/biossíntese , Peixe-Zebra/embriologia , Animais , Apoptose/fisiologia , Proteínas de Transporte/genética , Quinase 5 Dependente de Ciclina/genética , Quinase 5 Dependente de Ciclina/metabolismo , Ciclinas/genética , Embrião não Mamífero/citologia , Sistema Nervoso/citologia , Fosfoproteínas/genética , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
11.
FASEB J ; 24(11): 4336-42, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20601526

RESUMO

Many debilitating diseases, including neurodegenerative diseases, involve apoptosis. Several methods have been developed for visualizing apoptotic cells in vitro or in fixed tissues, but few tools are available for visualizing apoptotic cells in live animals. Here we describe a genetically encoded fluorescent reporter protein that labels apoptotic cells in live zebrafish embryos. During apoptosis, the phospholipid phosphatidylserine (PS) is exposed on the outer leaflet of the plasma membrane. The calcium-dependent protein Annexin V (A5) binds PS with high affinity, and biochemically purified, fluorescently labeled A5 probes have been widely used to detect apoptosis in vitro. Here we show that secreted A5 fused to yellow fluorescent protein specifically labels apoptotic cells in living zebrafish. We use this fluorescent probe to characterize patterns of apoptosis in living zebrafish larvae and to visualize neuronal cell death at single-cell resolution in vivo.


Assuntos
Apoptose , Microscopia/métodos , Peixe-Zebra/embriologia , Animais , Corantes Fluorescentes/metabolismo , Processamento de Imagem Assistida por Computador , Sondas Moleculares/genética , Sondas Moleculares/metabolismo
12.
Nature ; 437(7060): 831-7, 2005 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-16208361

RESUMO

Interplay among four genes--egl-1, ced-9, ced-4 and ced-3--controls the onset of programmed cell death in the nematode Caenorhabditis elegans. Activation of the cell-killing protease CED-3 requires CED-4. However, CED-4 is constitutively inhibited by CED-9 until its release by EGL-1. Here we report the crystal structure of the CED-4-CED-9 complex at 2.6 A resolution, and a complete reconstitution of the CED-3 activation pathway using homogeneous proteins of CED-4, CED-9 and EGL-1. One molecule of CED-9 binds to an asymmetric dimer of CED-4, but specifically recognizes only one of the two CED-4 molecules. This specific interaction prevents CED-4 from activating CED-3. EGL-1 binding induces pronounced conformational changes in CED-9 that result in the dissociation of the CED-4 dimer from CED-9. The released CED-4 dimer further dimerizes to form a tetramer, which facilitates the autoactivation of CED-3. Together, our studies provide important insights into the regulation of cell death activation in C. elegans.


Assuntos
Apoptose , Proteínas de Caenorhabditis elegans/química , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/química , Caenorhabditis elegans/citologia , Proteínas de Ligação ao Cálcio/química , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas Proto-Oncogênicas/química , Proteínas Proto-Oncogênicas/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Proteínas Reguladoras de Apoptose , Sítios de Ligação , Caspases/metabolismo , Ativação Enzimática , Modelos Moleculares , Complexos Multiproteicos/química , Complexos Multiproteicos/metabolismo , Ligação Proteica , Estrutura Quaternária de Proteína , Proteínas Proto-Oncogênicas c-bcl-2 , Proteínas Repressoras/química , Proteínas Repressoras/metabolismo , Especificidade por Substrato
13.
Nat Commun ; 12(1): 5284, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34489414

RESUMO

Cell death is a critical process that occurs normally in health and disease. However, its study is limited due to available technologies that only detect very late stages in the process or specific death mechanisms. Here, we report the development of a family of fluorescent biosensors called genetically encoded death indicators (GEDIs). GEDIs specifically detect an intracellular Ca2+ level that cells achieve early in the cell death process and that marks a stage at which cells are irreversibly committed to die. The time-resolved nature of a GEDI delineates a binary demarcation of cell life and death in real time, reformulating the definition of cell death. We demonstrate that GEDIs acutely and accurately report death of rodent and human neurons in vitro, and show that GEDIs enable an automated imaging platform for single cell detection of neuronal death in vivo in zebrafish larvae. With a quantitative pseudo-ratiometric signal, GEDIs facilitate high-throughput analysis of cell death in time-lapse imaging analysis, providing the necessary resolution and scale to identify early factors leading to cell death in studies of neurodegeneration.


Assuntos
Técnicas Biossensoriais , Morte Celular/genética , Regulação da Expressão Gênica no Desenvolvimento , Doenças Neurodegenerativas/genética , Neurônios/metabolismo , Animais , Cálcio/metabolismo , Córtex Cerebral/citologia , Córtex Cerebral/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Embrião não Mamífero , Corantes Fluorescentes/química , Genes Reporter , Ácido Glutâmico/farmacologia , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Larva/citologia , Larva/genética , Larva/crescimento & desenvolvimento , Larva/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Cultura Primária de Células , Ratos , Ratos Long-Evans , Análise de Célula Única/métodos , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo
14.
J Med Chem ; 63(3): 1142-1155, 2020 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-31977208

RESUMO

Ketamine, N,N-dimethyltryptamine (DMT), and other psychoplastogens possess enormous potential as neurotherapeutics due to their ability to potently promote neuronal growth. Here, we report the first-ever structure-activity relationship study with the explicit goal of identifying novel psychoplastogens. We have discovered several key features of the psychoplastogenic pharmacophore and used this information to develop N,N-dimethylaminoisotryptamine (isoDMT) psychoplastogens that are easier to synthesize, have improved physicochemical properties, and possess reduced hallucinogenic potential as compared to their DMT counterparts.


Assuntos
Alucinógenos/farmacologia , N,N-Dimetiltriptamina/farmacologia , Plasticidade Neuronal/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Animais , Alucinógenos/síntese química , Alucinógenos/química , Camundongos , Estrutura Molecular , N,N-Dimetiltriptamina/síntese química , N,N-Dimetiltriptamina/química , Relação Estrutura-Atividade , Peixe-Zebra
15.
Nat Commun ; 10(1): 4078, 2019 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-31501447

RESUMO

Anesthetics are generally associated with sedation, but some anesthetics can also increase brain and motor activity-a phenomenon known as paradoxical excitation. Previous studies have identified GABAA receptors as the primary targets of most anesthetic drugs, but how these compounds produce paradoxical excitation is poorly understood. To identify and understand such compounds, we applied a behavior-based drug profiling approach. Here, we show that a subset of central nervous system depressants cause paradoxical excitation in zebrafish. Using this behavior as a readout, we screened thousands of compounds and identified dozens of hits that caused paradoxical excitation. Many hit compounds modulated human GABAA receptors, while others appeared to modulate different neuronal targets, including the human serotonin-6 receptor. Ligands at these receptors generally decreased neuronal activity, but paradoxically increased activity in the caudal hindbrain. Together, these studies identify ligands, targets, and neurons affecting sedation and paradoxical excitation in vivo in zebrafish.


Assuntos
Comportamento Animal , Sedação Consciente , Receptores de GABA-A/metabolismo , Receptores de Serotonina/metabolismo , Peixe-Zebra/metabolismo , Animais , Ligantes , Inibição Neural , Neurônios/fisiologia , Antagonistas da Serotonina/química , Proteínas de Peixe-Zebra/metabolismo
16.
Brief Funct Genomic Proteomic ; 7(6): 483-90, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18784194

RESUMO

Despite their ubiquity and impact, psychiatric illnesses and other disorders of the central nervous system remain among the most poorly treated diseases. Most psychiatric medicines were discovered due to serendipitous observations of behavioural phenotypes in humans, rodents and other mammals. Extensive behaviour-based chemical screens would likely identify novel psychiatric drugs. However, large-scale chemical screens in mammals are inefficient and impractical. In contrast, zebrafish are very well suited for high-throughput behaviour-based drug discovery. Furthermore, the vast amounts of data generated from large-scale behavioural screens in zebrafish will facilitate a systems-level analysis of how chemicals affect behaviour. Unlike serendipitous discoveries in mammals, a comprehensive and integrative analysis of zebrafish chemobehavioural phenomics may identify functional relationships that would be missed by more reductionist approaches. Thus, behaviour-based chemical screens in the zebrafish may improve our understanding of neurobiology and accelerate the pace of psychiatric drug discovery.


Assuntos
Antipsicóticos/farmacologia , Comportamento Animal/efeitos dos fármacos , Descoberta de Drogas , Peixe-Zebra/fisiologia , Animais
17.
ACS Chem Biol ; 11(4): 842-9, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26845413

RESUMO

Many psychiatric drugs modulate the nervous system through multitarget mechanisms. However, systematic identification of multitarget compounds has been difficult using traditional in vitro screening assays. New approaches to phenotypic profiling in zebrafish can help researchers identify novel compounds with complex polypharmacology. For example, large-scale behavior-based chemical screens can rapidly identify large numbers of structurally diverse and phenotype-related compounds. Once these compounds have been identified, a systems-level analysis of their structures may help to identify statistically enriched target pathways. Together, systematic behavioral profiling and multitarget predictions may help researchers identify new behavior-modifying pathways and CNS therapeutics.


Assuntos
Comportamento Animal/efeitos dos fármacos , Polimedicação , Peixe-Zebra/fisiologia , Animais
18.
Front Pharmacol ; 5: 153, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25104936

RESUMO

Most neuroactive drugs were discovered through unexpected behavioral observations. Systematic behavioral screening is inefficient in most model organisms. But, automated technologies are enabling a new phase of discovery-based research in central nervous system (CNS) pharmacology. Researchers are using large-scale behavior-based chemical screens in zebrafish to discover compounds with new structures, targets, and functions. These compounds are powerful tools for understanding CNS signaling pathways. Substantial differences between human and zebrafish biology will make it difficult to translate these discoveries to clinical medicine. However, given the molecular genetic similarities between humans and zebrafish, it is likely that some of these compounds will have translational utility. We predict that the greatest new successes in CNS drug discovery will leverage many model systems, including in vitro assays, cells, rodents, and zebrafish.

19.
J Biomol Screen ; 18(1): 108-15, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22960781

RESUMO

Organophosphates are a class of highly toxic chemicals that includes many pesticides and chemical weapons. Exposure to organophosphates, either through accidents or acts of terrorism, poses a significant risk to human health and safety. Existing antidotes, in use for over 50 years, have modest efficacy and undesirable toxicities. Therefore, discovering new organophosphate antidotes is a high priority. Early life stage zebrafish exposed to organophosphates exhibit several phenotypes that parallel the human response to organophosphates, including behavioral deficits, paralysis, and eventual death. Here, we have developed a high-throughput zebrafish screen in a 96-well plate format to find new antidotes that counteract organophosphate-induced lethality. In a pilot screen of 1200 known drugs, we identified 16 compounds that suppress organophosphate toxicity in zebrafish. Several in vitro assays coupled with liquid chromatography/tandem mass spectrometry-based metabolite profiling enabled determination of mechanisms of action for several of the antidotes, including reversible acetylcholinesterase inhibition, cholinergic receptor antagonism, and inhibition of bioactivation. Therefore, the in vivo screen is capable of discovering organophosphate antidotes that intervene in distinct pathways. These findings suggest that zebrafish screens might be a broadly applicable approach for discovering compounds that counteract the toxic effects of accidental or malicious poisonous exposures.


Assuntos
Antídotos/farmacologia , Ensaios de Triagem em Larga Escala , Organofosfatos/toxicidade , Paration/toxicidade , Animais , Atropina/farmacologia , Linhagem Celular Tumoral , Antagonistas Colinérgicos/farmacologia , Reativadores da Colinesterase/farmacologia , Avaliação Pré-Clínica de Medicamentos , Emetina/farmacologia , Glicopirrolato/farmacologia , Humanos , Dose Letal Mediana , Metoclopramida/farmacologia , Neostigmina/farmacologia , Pirenzepina/análogos & derivados , Pirenzepina/farmacologia , Compostos de Pralidoxima/farmacologia , Peixe-Zebra
20.
Curr Biol ; 22(9): 830-6, 2012 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-22503503

RESUMO

Apoptotic cell death is essential for development and tissue homeostasis. Failure to clear apoptotic cells can ultimately cause inflammation and autoimmunity. Apoptosis has primarily been studied by staining of fixed tissue sections, and a clear understanding of the behavior of apoptotic cells in living tissue has been elusive. Here, we use a newly developed technique to track apoptotic cells in real time as they emerge and are cleared from the zebrafish brain. We find that apoptotic cells are remarkably motile, frequently migrating several cell diameters to the periphery of living tissues. F-actin remodeling occurs in surrounding cells, but also within the apoptotic cells themselves, suggesting a cell-autonomous component of motility. During the first 2 days of development, engulfment is rare, and most apoptotic cells lyse at the brain periphery. By 3 days postfertilization, most cell corpses are rapidly engulfed by macrophages. This engulfment requires the guanine nucleotide exchange factor elmo1. In elmo1-deficient macrophages, engulfment is rare and may occur through macropinocytosis rather than directed engulfment. These findings suggest that clearance of apoptotic cells in living vertebrates is accomplished by the combined actions of apoptotic cell migration and elmo1-dependent macrophage engulfment.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Apoptose , Movimento Celular , Macrófagos/fisiologia , Humanos
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