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Nani JV, Muotri AR, Hayashi MAF. Peering into the mind: unraveling schizophrenia's secrets using models. Mol Psychiatry 2024:10.1038/s41380-024-02728-w. [PMID: 39245692 DOI: 10.1038/s41380-024-02728-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 08/21/2024] [Accepted: 08/27/2024] [Indexed: 09/10/2024]
Abstract
Schizophrenia (SCZ) is a complex mental disorder characterized by a range of symptoms, including positive and negative symptoms, as well as cognitive impairments. Despite the extensive research, the underlying neurobiology of SCZ remain elusive. To overcome this challenge, the use of diverse laboratory modeling techniques, encompassing cellular and animal models, and innovative approaches like induced pluripotent stem cell (iPSC)-derived neuronal cultures or brain organoids and genetically engineered animal models, has been crucial. Immortalized cellular models provide controlled environments for investigating the molecular and neurochemical pathways involved in neuronal function, while iPSCs and brain organoids, derived from patient-specific sources, offer significant advantage in translational research by facilitating direct comparisons of cellular phenotypes between patient-derived neurons and healthy-control neurons. Animal models can recapitulate the different psychopathological aspects that should be modeled, offering valuable insights into the neurobiology of SCZ. In addition, invertebrates' models are genetically tractable and offer a powerful approach to dissect the core genetic underpinnings of SCZ, while vertebrate models, especially mammals, with their more complex nervous systems and behavioral repertoire, provide a closer approximation of the human condition to study SCZ-related traits. This narrative review provides a comprehensive overview of the diverse modeling approaches, critically evaluating their strengths and limitations. By synthesizing knowledge from these models, this review offers a valuable source for researchers, clinicians, and stakeholders alike. Integrating findings across these different models may allow us to build a more holistic picture of SCZ pathophysiology, facilitating the exploration of new research avenues and informed decision-making for interventions.
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Affiliation(s)
- João V Nani
- Department of Pharmacology, Escola Paulista de Medicina (EPM), Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil.
- National Institute for Translational Medicine (INCT-TM, CNPq/FAPESP/CAPES), Ribeirão Preto, Brazil.
| | - Alysson R Muotri
- Department of Pediatrics and Department of Molecular and Cellular Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Mirian A F Hayashi
- Department of Pharmacology, Escola Paulista de Medicina (EPM), Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil.
- National Institute for Translational Medicine (INCT-TM, CNPq/FAPESP/CAPES), Ribeirão Preto, Brazil.
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2
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Refai O, Rodriguez P, Gichi Z, Blakely RD. Forward genetic screen of the C. elegans million mutation library reveals essential, cell-autonomous contributions of BBSome proteins to dopamine signaling. J Neurochem 2024. [PMID: 39118406 DOI: 10.1111/jnc.16188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2024] [Revised: 07/11/2024] [Accepted: 07/12/2024] [Indexed: 08/10/2024]
Abstract
The nematode Caenorhabditis elegans is well known for its ability to support forward genetic screens to identify molecules involved in neuronal viability and signaling. The proteins involved in C. elegans dopamine (DA) regulation are highly conserved across evolution, with prior work demonstrating that the model can serve as an efficient platform to identify novel genes involved in disease-associated processes. To identify novel players in DA signaling, we took advantage of a recently developed library of pre-sequenced mutant nematodes arising from the million mutation project (MMP) to identify strains that display the DA-dependent swimming-induced-paralysis phenotype (Swip). Our screen identified novel mutations in the dopamine transporter encoding gene dat-1, whose loss was previously used to identify the Swip phenotype, as well as multiple genes with previously unknown connections to DA signaling. Here, we present our isolation and characterization of one of these genes, bbs-1, previously linked to the function of primary cilia in worms and higher organisms, including humans, and where loss-of-function mutations result in a human disorder known as Bardet-Biedl syndrome. Our studies of C. elegans BBS-1 protein, as well as other proteins that are known to be assembled into a higher order complex (the BBSome) reveal that functional or structural disruption of this complex leads to exaggerated C. elegans DA signaling to produce Swip via a cell-autonomous mechanism. We provide evidence that not only does the proper function of cilia in C. elegans DA neurons support normal swimming behavior, but also that bbs-1 maintains normal levels of DAT-1 trafficking or function via a RHO-1 and SWIP-13/MAPK-15 dependent pathway where mutants may contribute to Swip independent of altered ciliary function. Together, these studies demonstrate novel contributors to DA neuron function in the worm and demonstrate the utility and efficiency of forward genetic screens using the MMP library.
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Affiliation(s)
- Osama Refai
- Department of Biomedical Science, Florida Atlantic University, Boca Raton, Florida, USA
| | - Peter Rodriguez
- Department of Biomedical Science, Florida Atlantic University, Boca Raton, Florida, USA
| | - Zayna Gichi
- Department of Biomedical Science, Florida Atlantic University, Boca Raton, Florida, USA
| | - Randy D Blakely
- Department of Biomedical Science, Florida Atlantic University, Boca Raton, Florida, USA
- Stiles-Nicholson Brain Institute, Florida Atlantic University, Jupiter, Florida, USA
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3
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Rodriguez P, Blakely RD. Sink or swim: Does a worm paralysis phenotype hold clues to neurodegenerative disease? J Cell Physiol 2024; 239:e31125. [PMID: 37795580 DOI: 10.1002/jcp.31125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Revised: 09/07/2023] [Accepted: 09/11/2023] [Indexed: 10/06/2023]
Abstract
Receiving a neurodegenerative disease (NDD) diagnosis, such as Alzheimer's disease, Parkinson's disease, Huntington's disease, or amyotrophic lateral sclerosis, is devastating, particularly given the limited options for treatment. Advances in genetic technologies have allowed for efficient modeling of NDDs in animals and brought hope for new disease-modifying medications. The complexity of the mammalian brain and the costs and time needed to identify and develop therapeutic leads limits progress. Modeling NDDs in invertebrates, such as the fruit fly Drosophila melanogaster and the nematode Caenorhabditis elegans, offers orders of magnitude increases in speed of genetic analysis and manipulation, and can be pursued at substantially reduced cost, providing an important, platform complement and inform research with mammalian NDD models. In this review, we describe how our efforts to exploit C. elegans for the study of neural signaling and health led to the discovery of a paralytic phenotype (swimming-induced paralysis) associated with altered dopamine signaling and, surprisingly, to the discovery of a novel gene and pathway whose dysfunction in glial cells triggers neurodegeneration. Research to date on swip-10 and its putative mammalian ortholog MBLAC1, suggests that a tandem analysis will offer insights into NDD mechanisms and insights into novel, disease-modifying therapeutics.
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Affiliation(s)
- Peter Rodriguez
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Boca Raton, Florida, USA
| | - Randy D Blakely
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Boca Raton, Florida, USA
- Stiles-Nicholson Brain Institute, Florida Atlantic University, Jupiter, Florida, USA
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4
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Clark AS, Huayta J, Morton KS, Meyer JN, San-Miguel A. Morphological hallmarks of dopaminergic neurodegeneration are associated with altered neuron function in Caenorhabditis elegans. Neurotoxicology 2024; 100:100-106. [PMID: 38070655 PMCID: PMC10872346 DOI: 10.1016/j.neuro.2023.12.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 11/26/2023] [Accepted: 12/01/2023] [Indexed: 12/19/2023]
Abstract
Caenorhabditis elegans (C. elegans) is an excellent model system to study neurodegenerative diseases, such as Parkinson's disease, as it enables analysis of both neuron morphology and function in live animals. Multiple structural changes in neurons, such as cephalic dendrite morphological abnormalities, have been considered hallmarks of neurodegeneration in this model, but their relevance to changes in neuron function are not entirely clear. We sought to test whether hallmark morphological changes associated with chemically induced dopaminergic neuron degeneration, such as dendrite blebbing, breakage, and loss, are indicative of neuronal malfunction and result in changes in behavior. We adapted an established dopaminergic neuronal function assay by measuring paralysis in the presence of exogenous dopamine, which revealed clear differences between cat-2 dopamine deficient mutants, wildtype worms, and dat-1 dopamine abundant mutants. Next, we integrated an automated image processing algorithm and a microfluidic device to segregate worm populations by their cephalic dendrite morphologies. We show that nematodes with dopaminergic dendrite degeneration markers, such as blebbing or breakage, paralyze at higher rates in a dopamine solution, providing evidence that dopaminergic neurodegeneration morphologies are correlated with functional neuronal outputs.
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Affiliation(s)
- Andrew S Clark
- Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA
| | - Javier Huayta
- Nicholas School of the Environment, Duke University, Durham, NC, USA
| | | | - Joel N Meyer
- Nicholas School of the Environment, Duke University, Durham, NC, USA
| | - Adriana San-Miguel
- Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA.
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Salgueiro WG, Soares MV, Martins CF, Paula FR, Rios-Anjos RM, Carrazoni T, Mori MA, Müller RU, Aschner M, Dal Belo CA, Ávila DS. Dopaminergic modulation by quercetin: In silico and in vivo evidence using Caenorhabditis elegans as a model. Chem Biol Interact 2023; 382:110610. [PMID: 37348670 PMCID: PMC10527449 DOI: 10.1016/j.cbi.2023.110610] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Revised: 06/12/2023] [Accepted: 06/19/2023] [Indexed: 06/24/2023]
Abstract
Quercetin is a flavonol widely distributed in plants and has various described biological functions. Several studies have reported on its ability to restore neuronal function in a wide variety of disease models, including animal models of neurodegenerative disorders such as Parkinson's disease. Quercetin per se can act as a neuroprotector/neuromodulator, especially in diseases related to impaired dopaminergic neurotransmission. However, little is known about how quercetin interacts with the dopaminergic machinery. Here we employed the nematode Caenorhabditis elegans to study this putative interaction. After observing behavioral modulation, mutant analysis and gene expression in C. elegans upon exposure to quercetin at a concentration that does not protect against MPTP, we constructed a homology-based dopamine transporter protein model to conduct a docking study. This led to suggestive evidence on how quercetin may act as a dopaminergic modulator by interacting with C. elegans' dopamine transporter and alter the nematode's exploratory behavior. Consistent with this model, quercetin controls C. elegans behavior in a way dependent on the presence of both the dopamine transporter (dat-1), which is up-regulated upon quercetin exposure, and the dopamine receptor 2 (dop-2), which appears to be mandatory for dat-1 up-regulation. Our data propose an interaction with the dopaminergic machinery that may help to establish the effects of quercetin as a neuromodulator.
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Affiliation(s)
- Willian Goulart Salgueiro
- Research Group in Biochemistry and Toxicology in Caenorhabditis elegans (GBToxCe), Federal University of Pampa - UNIPAMPA, CEP 97500-970, Uruguaiana, RS, Brazil; Department of Biochemistry and Tissue Biology, University of Campinas, Monteiro Lobato Avenue, 255, Campinas, São Paulo, 13083-862, Brazil; Cologne Excellence Cluster on Cellular Stress Responses in Aging-associated Diseases (CECAD), University of Cologne, Cologne, 50931, Germany; Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Cologne, Germany
| | - Marcell Valandro Soares
- Research Group in Biochemistry and Toxicology in Caenorhabditis elegans (GBToxCe), Federal University of Pampa - UNIPAMPA, CEP 97500-970, Uruguaiana, RS, Brazil; Department of Biochemistry and Molecular Biology, Post-graduate Program in Biological Sciences, Federal University of Santa Maria, Camobi, 97105-900, Santa Maria, RS, Brazil
| | - Cassiano Fiad Martins
- Research Group in Biochemistry and Toxicology in Caenorhabditis elegans (GBToxCe), Federal University of Pampa - UNIPAMPA, CEP 97500-970, Uruguaiana, RS, Brazil
| | - Fávero Reisdorfer Paula
- Laboratory for Development and Quality Control in Medicines (LDCQ), Federal University of Pampa, Uruguaiana, RS, Brazil
| | | | - Thiago Carrazoni
- Neurobiology and Toxinology Laboratory, (LANETOX), Federal University of Pampa - UNIPAMPA, CEP 97300-000, São Gabriel, RS, Brazil
| | - Marcelo A Mori
- Department of Biochemistry and Tissue Biology, University of Campinas, Monteiro Lobato Avenue, 255, Campinas, São Paulo, 13083-862, Brazil; Obesity and Comorbidities Research Center (OCRC), University of Campinas, Campinas, SP, Brazil; Experimental Medicine Research Cluster, University of Campinas, Campinas, SP, Brazil
| | - Roman-Ulrich Müller
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-associated Diseases (CECAD), University of Cologne, Cologne, 50931, Germany; Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Cologne, Germany
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY, 10461, USA
| | - Cháriston André Dal Belo
- Department of Biochemistry and Molecular Biology, Post-graduate Program in Biological Sciences, Federal University of Santa Maria, Camobi, 97105-900, Santa Maria, RS, Brazil; Neurobiology and Toxinology Laboratory, (LANETOX), Federal University of Pampa - UNIPAMPA, CEP 97300-000, São Gabriel, RS, Brazil; Multidisciplinar Department, Federal University of São Paulo (UNIFESP), Angelica Street, 100- CEP 06110295, Osasco, SP, Brazil
| | - Daiana Silva Ávila
- Research Group in Biochemistry and Toxicology in Caenorhabditis elegans (GBToxCe), Federal University of Pampa - UNIPAMPA, CEP 97500-970, Uruguaiana, RS, Brazil; Department of Biochemistry and Molecular Biology, Post-graduate Program in Biological Sciences, Federal University of Santa Maria, Camobi, 97105-900, Santa Maria, RS, Brazil.
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Clark AS, Huayta J, Morton KS, Meyer JN, San-Miguel A. Morphological hallmarks of dopaminergic neurodegeneration are associated with altered neuron function in Caenorhabditis elegans. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.22.554364. [PMID: 37662210 PMCID: PMC10473754 DOI: 10.1101/2023.08.22.554364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
Caenorhabditis elegans (C. elegans) is an excellent model system to study neurodegenerative diseases, such as Parkinson's disease, as it enables analysis of both neuron morphology and function in live animals. Multiple structural changes in neurons, such as cephalic dendrite morphological abnormalities, have been considered hallmarks of neurodegeneration in this model, but their relevance to changes in neuron function are not entirely clear. We sought to test whether hallmark morphological changes associated with chemically induced dopaminergic neuron degeneration, such as dendrite blebbing, breakage, and loss, are indicative of neuronal malfunction and result in changes in behavior. We adapted an established dopaminergic neuronal function assay by measuring paralysis in the presence of exogenous dopamine, which revealed clear differences between cat-2 dopamine deficient mutants, wildtype worms, and dat-1 dopamine abundant mutants. Next, we integrated an automated image processing algorithm and a microfluidic device to segregate worm populations by their cephalic dendrite morphologies. We show that nematodes with dopaminergic dendrite degeneration markers, such as blebbing or breakage, paralyze at higher rates in a dopamine solution, providing evidence that dopaminergic neurodegeneration morphologies are correlated with functional neuronal outputs.
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Affiliation(s)
- Andrew S Clark
- Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
| | - Javier Huayta
- Nicholas School of the Environment, Duke University, Durham, North Carolina, USA
| | - Katherine S Morton
- Nicholas School of the Environment, Duke University, Durham, North Carolina, USA
| | - Joel N Meyer
- Nicholas School of the Environment, Duke University, Durham, North Carolina, USA
| | - Adriana San-Miguel
- Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
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7
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Lima TRR, Martins AC, Pereira LC, Aschner M. Toxic Effects Induced by Diuron and Its Metabolites in Caenorhabditis elegans. Neurotox Res 2022; 40:1812-1823. [PMID: 36306114 DOI: 10.1007/s12640-022-00596-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 09/26/2022] [Accepted: 10/18/2022] [Indexed: 01/18/2023]
Abstract
The toxicity of diuron herbicide and its metabolites has been extensively investigated; however, their precise toxic mechanisms have yet to be fully appreciated. In this context, we evaluated the toxic mechanism of diuron, 3,4-dichloroaniline (DCA) and 3-(3,4-dichlorophenyl)-1-methylurea (DCPMU), using Caenorhabditis elegans (C. elegans) in the L1 larval stage. For this purpose, worms were acutely exposed to the test chemicals with a preliminary concentration range of 0.5 to 500 μM and first analyzed for lethality (%). Next, the highest concentration (500 μM) was considered for survival (%), reactive oxygen and nitrogen species (RONS), glutathione (GSH) and ATP levels, autophagy index, behavior, and dopaminergic neurodegeneration parameters. Interestingly, increased lethality (%) was found for all chemicals at the higher concentrations tested (100 and 500 μM), with significant differences at 500 μM DCA (p < 0.05). A decrease in the median survival was observed mainly for DCA. Although no changes were observed in RONS production, GSH levels were significantly increased upon diuron and DCA treatment, likely reflecting an attempt to restore the redox status. Moreover, diuron and its metabolites impaired ATP levels, suggesting an alteration in mitochondrial function. The latter may trigger autophagy as an adaptive survival mechanism, but this was not observed in C. elegans. Dopaminergic neurotoxicity was observed upon treatment with all the tested chemicals, but only diuron induced alterations in the worms' locomotor behavior. Combined, these results indicate that exposure to high concentrations of diuron and its metabolites elicit distinct adverse outcomes in C. elegans, and DCA in particular, plays an important role in the overall toxicity observed in this experimental model.
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Affiliation(s)
- Thania Rios Rossi Lima
- Medical School - TOXICAM, UNIPEX, São Paulo State University (Unesp), Block 5 Botucatu, São Paulo, 18618-970, Brazil. .,Center for Evaluation of Environmental Impact On Human Health (TOXICAM), Medical School, Unesp, Botucatu, SP, Brazil.
| | - Airton C Martins
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Lílian Cristina Pereira
- Center for Evaluation of Environmental Impact On Human Health (TOXICAM), Medical School, Unesp, Botucatu, SP, Brazil.,School of Agriculture, São Paulo State University (Unesp), Botucatu, SP, Brazil
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, USA
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Refai O, Aggarwal S, Cheng MH, Gichi Z, Salvino JM, Bahar I, Blakely RD, Mortensen OV. Allosteric Modulator KM822 Attenuates Behavioral Actions of Amphetamine in Caenorhabditis elegans through Interactions with the Dopamine Transporter DAT-1. Mol Pharmacol 2022; 101:123-131. [PMID: 34906999 PMCID: PMC8969146 DOI: 10.1124/molpharm.121.000400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 12/03/2021] [Indexed: 11/22/2022] Open
Abstract
Aberrant dopamine (DA) signaling is associated with several psychiatric disorders, such as autism, bipolar disorder, addiction, and Parkinson's disease, and several medications that target the DA transporter (DAT) can induce or treat these disorders. In addition, psychostimulants, such as cocaine and D-amphetamine (AMPH), rely on the competitive interactions with the transporter's substrate binding site to produce their rewarding effects. Agents that exhibit noncompetitive, allosteric modulation of DAT remain an important topic of investigation due to their potential therapeutic applications. We previously identified a novel allosteric modulator of human DAT, KM822, that can decrease the affinity of cocaine for DAT and attenuate cocaine-elicited behaviors; however, whether DAT is the sole mediator of KM822 actions in vivo is unproven given the large number of potential off-target sites. Here, we provide in silico and in vitro evidence that the allosteric site engaged by KM822 is conserved between human DAT and Caenorhabditis elegans DAT-1. KM822 binds to a similar pocket in DAT-1 as previously identified in human DAT. In functional dopamine uptake assays, KM822 affects the interaction between AMPH and DAT-1 by reducing the affinity of AMPH for DAT-1. Finally, through a combination of genetic and pharmacological in vivo approaches we provide evidence that KM822 diminishes the behavioral actions of AMPH on swimming-induced paralysis through a direct allosteric modulation of DAT-1. More broadly, our findings demonstrate allosteric modulation of DAT as a behavior modifying strategy and suggests that Caenorhabditis elegans can be operationalized to identify and investigate the interactions of DAT allosteric modulators. SIGNIFICANCE STATEMENT: We previously demonstrated that the dopamine transporter (DAT) allosteric modulator KM822 decreases cocaine affinity for human DAT. Here, using in silico and in vivo genetic approaches, we extend this finding to interactions with amphetamine, demonstrating evolutionary conservation of the DAT allosteric site. In Caenorhabditis elegans, we report that KM822 suppresses amphetamine behavioral effects via specific interactions with DAT-1. Our findings reveal Caenorhabditis elegans as a new tool to study allosteric modulation of DAT and its behavioral consequences.
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Affiliation(s)
- Osama Refai
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Jupiter, Florida (O.R., Z.G., R.D.B.); Stiles-Nicholson Brain Institute, Florida Atlantic University, Jupiter, Florida (O.R., R.D.B.); Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania (S.A., O.V.M.); Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania (M.H.C., I.B.); and The Wistar Institute, Philadelphia, Pennsylvania (J.M.S.)
| | - Shaili Aggarwal
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Jupiter, Florida (O.R., Z.G., R.D.B.); Stiles-Nicholson Brain Institute, Florida Atlantic University, Jupiter, Florida (O.R., R.D.B.); Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania (S.A., O.V.M.); Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania (M.H.C., I.B.); and The Wistar Institute, Philadelphia, Pennsylvania (J.M.S.)
| | - Mary Hongying Cheng
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Jupiter, Florida (O.R., Z.G., R.D.B.); Stiles-Nicholson Brain Institute, Florida Atlantic University, Jupiter, Florida (O.R., R.D.B.); Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania (S.A., O.V.M.); Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania (M.H.C., I.B.); and The Wistar Institute, Philadelphia, Pennsylvania (J.M.S.)
| | - Zayna Gichi
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Jupiter, Florida (O.R., Z.G., R.D.B.); Stiles-Nicholson Brain Institute, Florida Atlantic University, Jupiter, Florida (O.R., R.D.B.); Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania (S.A., O.V.M.); Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania (M.H.C., I.B.); and The Wistar Institute, Philadelphia, Pennsylvania (J.M.S.)
| | - Joseph M Salvino
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Jupiter, Florida (O.R., Z.G., R.D.B.); Stiles-Nicholson Brain Institute, Florida Atlantic University, Jupiter, Florida (O.R., R.D.B.); Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania (S.A., O.V.M.); Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania (M.H.C., I.B.); and The Wistar Institute, Philadelphia, Pennsylvania (J.M.S.)
| | - Ivet Bahar
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Jupiter, Florida (O.R., Z.G., R.D.B.); Stiles-Nicholson Brain Institute, Florida Atlantic University, Jupiter, Florida (O.R., R.D.B.); Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania (S.A., O.V.M.); Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania (M.H.C., I.B.); and The Wistar Institute, Philadelphia, Pennsylvania (J.M.S.)
| | - Randy D Blakely
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Jupiter, Florida (O.R., Z.G., R.D.B.); Stiles-Nicholson Brain Institute, Florida Atlantic University, Jupiter, Florida (O.R., R.D.B.); Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania (S.A., O.V.M.); Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania (M.H.C., I.B.); and The Wistar Institute, Philadelphia, Pennsylvania (J.M.S.)
| | - Ole V Mortensen
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Jupiter, Florida (O.R., Z.G., R.D.B.); Stiles-Nicholson Brain Institute, Florida Atlantic University, Jupiter, Florida (O.R., R.D.B.); Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania (S.A., O.V.M.); Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania (M.H.C., I.B.); and The Wistar Institute, Philadelphia, Pennsylvania (J.M.S.)
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Formisano R, Rosikon KD, Singh A, Dhillon HS. The dopamine membrane transporter plays an active modulatory role in synaptic dopamine homeostasis. J Neurosci Res 2021; 100:1551-1559. [PMID: 34747520 PMCID: PMC9079189 DOI: 10.1002/jnr.24965] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 08/17/2021] [Accepted: 08/29/2021] [Indexed: 11/11/2022]
Abstract
Modulatory mechanisms of neurotransmitter release and clearance are highly controlled processes whose finely tuned regulation is critical for functioning of the nervous system. Dysregulation of the monoamine neurotransmitter dopamine can lead to several neuropathies. Synaptic modulation of dopamine is known to involve pre-synaptic D2 auto-receptors and acid sensing ion channels. In addition, the dopamine membrane transporter (DAT), which is responsible for clearance of dopamine from the synaptic cleft, is suspected to play an active role in modulating release of dopamine. Using functional imaging on the Caenorhabditis elegans model system, we show that DAT-1 acts as a negative feedback modulator to neurotransmitter vesicle fusion. Results from our fluorescence recovery after photo-bleaching (FRAP) based experiments were followed up with and reaffirmed using swimming-induced paralysis behavioral assays. Utilizing our numerical FRAP data we have developed a mechanistic model to dissect the dynamics of synaptic vesicle fusion, and compare the feedback effects of DAT-1 with the dopamine auto-receptor. Our experimental results and the mechanistic model are of potential broader significance, as similar dynamics are likely to be used by other synaptic modulators including membrane transporters for other neurotransmitters across species.
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Affiliation(s)
- Rosaria Formisano
- Department of Biological Sciences, Delaware Center for Neuroscience Research, Delaware State University, Dover, DE, USA
| | - Katarzyna D Rosikon
- Department of Biological Sciences, Delaware Center for Neuroscience Research, Delaware State University, Dover, DE, USA
| | - Abhyudai Singh
- Department of Electrical and Computer Engineering, Biomedical Engineering, Data Sciences Institute, University of Delaware, Newark, DE, USA
| | - Harbinder S Dhillon
- Department of Biological Sciences, Delaware Center for Neuroscience Research, Delaware State University, Dover, DE, USA
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Wei CC, Yang NC, Huang CW. Zearalenone Induces Dopaminergic Neurodegeneration via DRP-1-Involved Mitochondrial Fragmentation and Apoptosis in a Caenorhabditis elegans Parkinson's Disease Model. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:12030-12038. [PMID: 34586801 DOI: 10.1021/acs.jafc.1c05836] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The contamination of mycotoxin zearalenone (ZEN) in foods has been reported worldwide, resulting in potential risks to food safety. However, the toxic mechanism of ZEN on neurodegenerative diseases has not been fully elucidated. Therefore, this study conducted in vivo ZEN neurotoxicity assessment on Parkinson's disease (PD)-related dopaminergic neurodegeneration and mitochondrial dysfunction using Caenorhabditis elegans. The results demonstrated that dopaminergic neuron damage was induced by ZEN exposure (1.25, 10, and 50 μM), and dopaminergic neuron-related behaviors were adversely affected subsequently. Additionally, the mitochondrial fragmentation was significantly increased by ZEN exposure. Moreover, upregulated expression of mitochondrial fission and cell apoptosis-related genes (drp-1, egl-1, ced-4, and ced-3) revealed the crucial role of DRP-1 on ZEN-induced neurotoxicity, which was further confirmed by drp-1 mutant and RNAi assays. In conclusion, our study indicates ZEN-induced dopaminergic neurodegeneration via DRP-1-involved mitochondrial fragmentation and apoptosis, which might cause harmful effects on PD-related symptoms.
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Affiliation(s)
- Chia-Cheng Wei
- Institute of Food Safety and Health, College of Public Health, National Taiwan University, No. 17, Xuzhou Rd., Taipei 100, Taiwan
- Department of Public Health, College of Public Health, National Taiwan University, No. 17, Xuzhou Rd., Taipei 100, Taiwan
| | - Nien-Chieh Yang
- Institute of Food Safety and Health, College of Public Health, National Taiwan University, No. 17, Xuzhou Rd., Taipei 100, Taiwan
| | - Chi-Wei Huang
- Institute of Food Safety and Health, College of Public Health, National Taiwan University, No. 17, Xuzhou Rd., Taipei 100, Taiwan
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11
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Improved Method for the Total Synthesis of Azaperone and Investigation of Its Electrochemical Behavior in Aqueous Solution. Chem Res Chin Univ 2021. [DOI: 10.1007/s40242-021-1061-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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12
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Torres Valladares D, Kudumala S, Hossain M, Carvelli L. Caenorhabditis elegans as an in vivo Model to Assess Amphetamine Tolerance. BRAIN, BEHAVIOR AND EVOLUTION 2021; 95:247-255. [PMID: 33831863 DOI: 10.1159/000514858] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 01/27/2021] [Indexed: 11/19/2022]
Abstract
Amphetamine is a potent psychostimulant also used to treat attention deficit/hyperactivity disorder and narcolepsy. In vivo and in vitro data have demonstrated that amphetamine increases the amount of extra synaptic dopamine by both inhibiting reuptake and promoting efflux of dopamine through the dopamine transporter. Previous studies have shown that chronic use of amphetamine causes tolerance to the drug. Thus, since the molecular mechanisms underlying tolerance to amphetamine are still unknown, an animal model to identify the neurochemical mechanisms associated with drug tolerance is greatly needed. Here we took advantage of a unique behavior caused by amphetamine in Caenorhabditis elegans to investigate whether this simple, but powerful, genetic model develops tolerance following repeated exposure to amphetamine. We found that at least 3 treatments with 0.5 mM amphetamine were necessary to see a reduction in the amphetamine-induced behavior and, thus, to promote tolerance. Moreover, we found that, after intervals of 60/90 minutes between treatments, animals were more likely to exhibit tolerance than animals that underwent 10-minute intervals between treatments. Taken together, our results show that C. elegans is a suitable system to study tolerance to drugs of abuse such as amphetamines.
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Affiliation(s)
- Dayana Torres Valladares
- Department of Biology, Harriet L. Wilkes Honors College, Florida Atlantic University, Jupiter, Florida, USA
| | - Sirisha Kudumala
- Department of Biology, Harriet L. Wilkes Honors College, Florida Atlantic University, Jupiter, Florida, USA
| | - Murad Hossain
- Department of Pharmaceutical Sciences, School of Health and Life Sciences, North South University, Dhaka, Bangladesh
| | - Lucia Carvelli
- Department of Biology, Harriet L. Wilkes Honors College, Florida Atlantic University, Jupiter, Florida, USA.,Brain Institute, Florida Atlantic University, Jupiter, Florida, USA
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13
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Dominguez-Meijide A, Parrales V, Vasili E, González-Lizárraga F, König A, Lázaro DF, Lannuzel A, Haik S, Del Bel E, Chehín R, Raisman-Vozari R, Michel PP, Bizat N, Outeiro TF. Doxycycline inhibits α-synuclein-associated pathologies in vitro and in vivo. Neurobiol Dis 2021; 151:105256. [PMID: 33429042 DOI: 10.1016/j.nbd.2021.105256] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 12/29/2020] [Accepted: 01/06/2021] [Indexed: 02/07/2023] Open
Abstract
Parkinson's disease (PD) and dementia with Lewy bodies (DLB) are neurodegenerative disorders characterized by the misfolding and aggregation of alpha-synuclein (aSyn). Doxycycline, a tetracyclic antibiotic shows neuroprotective effects, initially proposed to be due to its anti-inflammatory properties. More recently, an additional mechanism by which doxycycline may exert its neuroprotective effects has been proposed as it has been shown that it inhibits amyloid aggregation. Here, we studied the effects of doxycycline on aSyn aggregation in vivo, in vitro and in a cell free system using real-time quaking induced conversion (RT-QuiC). Using H4, SH-SY5Y and HEK293 cells, we found that doxycycline decreases the number and size of aSyn aggregates in cells. In addition, doxycycline inhibits the aggregation and seeding of recombinant aSyn, and attenuates the production of mitochondrial-derived reactive oxygen species. Finally, we found that doxycycline induces a cellular redistribution of aggregates in a C.elegans animal model of PD, an effect that is associated with a recovery of dopaminergic function. In summary, we provide strong evidence that doxycycline treatment may be an effective strategy against synucleinopathies.
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Affiliation(s)
- Antonio Dominguez-Meijide
- Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Goettingen, Goettingen, Germany; Laboratory of Neuroanatomy and Experimental Neurology, Dept. of Morphological Sciences, CIMUS, IDIS, University of Santiago de Compostela, Santiago de Compostela, Spain; Networking Research Center on Neurodegenerative Diseases (CIBERNED), Madrid, Spain
| | - Valeria Parrales
- Paris Brain Institute, Inserm U 1127, CNRS UMR 7225, Sorbonne Université, F-75013 Paris, France
| | - Eftychia Vasili
- Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Goettingen, Goettingen, Germany
| | | | - Annekatrin König
- Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Goettingen, Goettingen, Germany
| | - Diana F Lázaro
- Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Goettingen, Goettingen, Germany
| | - Annie Lannuzel
- Paris Brain Institute, Inserm U 1127, CNRS UMR 7225, Sorbonne Université, F-75013 Paris, France; University Hospital of Pointe-à-Pitre, Neurology Department, route de Chauvel, 97139 Abymes, Guadeloupe
| | - Stéphane Haik
- Paris Brain Institute, Inserm U 1127, CNRS UMR 7225, Sorbonne Université, F-75013 Paris, France; AP-HP, Cellule Nationale de Référence des Maladies de Creutzfeldt-Jakob, University Hospital Pitié-Salpêtrière, Paris F-75013, France
| | - Elaine Del Bel
- Department of Basic and Oral Biology, Faculty of Odontology of Ribeirão Preto, University of São Paulo (USP), Av do Café s/n, São Paulo, Brazil
| | - Rosana Chehín
- Instituto de Investigación en Medicina Molecular y Celular Aplicada (IMMCA) (CONICET-UNT-SIPROSA), Argentina
| | - Rita Raisman-Vozari
- Paris Brain Institute, Inserm U 1127, CNRS UMR 7225, Sorbonne Université, F-75013 Paris, France
| | - Patrick P Michel
- Paris Brain Institute, Inserm U 1127, CNRS UMR 7225, Sorbonne Université, F-75013 Paris, France
| | - Nicolas Bizat
- Paris Brain Institute, Inserm U 1127, CNRS UMR 7225, Sorbonne Université, F-75013 Paris, France; Faculté de Pharmacie de Paris, Paris University, 4 avenue de l'Observatoire, Paris F-75006, France.
| | - Tiago Fleming Outeiro
- Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Goettingen, Goettingen, Germany; Max Planck Institute for Experimental Medicine, Goettingen, Germany; Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle Upon Tyne NE2 4HH, UK.
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14
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Involvement of dopamine receptor in the actions of non-psychoactive phytocannabinoids. Biochem Biophys Res Commun 2020; 533:1366-1370. [PMID: 33097185 DOI: 10.1016/j.bbrc.2020.10.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 10/09/2020] [Indexed: 01/06/2023]
Abstract
Nematode Caenorhabditis elegans (C. elegans) exhibited a vigorous swimming behavior in liquid medium. Addition of dopamine inhibited the swimming behavior, causing paralysis in 65% of wild-type nematodes. Interestingly, phytocannabinoids cannabidiol (CBD) or cannabidivarin (CBDV), caused paralysis in 40% of the animals. Knockout of DOP-3, the dopamine D2-like receptor critical for locomotor behavior, eliminated the paralysis induced by dopamine, CBD, and CBDV. In contrast, both CBD and CBDV caused paralysis in animals lacking CAT-2, an enzyme necessary for dopamine synthesis. Co-administration of dopamine with either CBD or CBDV caused paralysis similar to that of either phytocannabinoid treatment alone. These data support the notion that CBD and CBDV act as functional partial agonists on dopamine D2-like receptors in vivo. The discovery that dopamine receptor is involved in the actions of phytocannabinoids moves a significant step toward our understanding of the mechanisms for medical uses of cannabis in the treatment of neurological and psychiatric disorders.
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15
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Krum BN, Martins AC, Queirós L, Ferrer B, Milne GL, Soares FAA, Fachinetto R, Aschner M. Haloperidol Interactions with the dop-3 Receptor in Caenorhabditis elegans. Mol Neurobiol 2020; 58:304-316. [PMID: 32935232 DOI: 10.1007/s12035-020-02124-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 09/05/2020] [Indexed: 11/29/2022]
Abstract
Haloperidol is a typical antipsychotic drug commonly used to treat a broad range of psychiatric disorders related to dysregulations in the neurotransmitter dopamine (DA). DA modulates important physiologic functions and perturbations in Caenorhabditis elegans (C. elegans) and, its signaling have been associated with alterations in behavioral, molecular, and morphologic properties in C. elegans. Here, we evaluated the possible involvement of dopaminergic receptors in the onset of these alterations followed by haloperidol exposure. Haloperidol increased lifespan and decreased locomotor behavior (basal slowing response, BSR, and locomotion speed via forward speed) of the worms. Moreover, locomotion speed recovered to basal conditions upon haloperidol withdrawal. Haloperidol also decreased DA levels, but it did not alter neither dop-1, dop-2, and dop-3 gene expression, nor CEP dopaminergic neurons' morphology. These effects are likely due to haloperidol's antagonism of the D2-type DA receptor, dop-3. Furthermore, this antagonism appears to affect mechanistic pathways involved in the modulation and signaling of neurotransmitters such as octopamine, acetylcholine, and GABA, which may underlie at least in part haloperidol's effects. These pathways are conserved in vertebrates and have been implicated in a range of disorders. Our novel findings demonstrate that the dop-3 receptor plays an important role in the effects of haloperidol.
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Affiliation(s)
- Bárbara Nunes Krum
- Departamento de Fisiologia e Farmacologia, Centro de Ciências da Saúde, Universidade Federal de Santa Maria, Camobi, Santa Maria, RS, 97105-900, Brazil.,Department of Molecular Pharmacology, Albert Einstein College of Medicine, Yeshiva University, Forccheimer 209, 1300 Morris Park Avenue, Bronx, NY, 10461, USA
| | - Airton C Martins
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Yeshiva University, Forccheimer 209, 1300 Morris Park Avenue, Bronx, NY, 10461, USA
| | - Libânia Queirós
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Yeshiva University, Forccheimer 209, 1300 Morris Park Avenue, Bronx, NY, 10461, USA.,Department of Biology and CESAM (Centre for Environmental and Marine Studies), University of Aveiro, 3810-193, Aveiro, Portugal
| | - Beatriz Ferrer
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Yeshiva University, Forccheimer 209, 1300 Morris Park Avenue, Bronx, NY, 10461, USA
| | - Ginger L Milne
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, 37240, USA
| | - Félix Alexandre Antunes Soares
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Yeshiva University, Forccheimer 209, 1300 Morris Park Avenue, Bronx, NY, 10461, USA.,Departamento de Bioquímica e Biologia Molecular, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, Camobi, Santa Maria, RS, 97105-900, Brazil
| | - Roselei Fachinetto
- Departamento de Fisiologia e Farmacologia, Centro de Ciências da Saúde, Universidade Federal de Santa Maria, Camobi, Santa Maria, RS, 97105-900, Brazil
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Yeshiva University, Forccheimer 209, 1300 Morris Park Avenue, Bronx, NY, 10461, USA.
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16
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Robinson SB, Refai O, Hardaway JA, Sturgeon S, Popay T, Bermingham DP, Freeman P, Wright J, Blakely RD. Dopamine-dependent, swimming-induced paralysis arises as a consequence of loss of function mutations in the RUNX transcription factor RNT-1. PLoS One 2019; 14:e0216417. [PMID: 31083672 PMCID: PMC6513266 DOI: 10.1371/journal.pone.0216417] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 04/21/2019] [Indexed: 11/18/2022] Open
Abstract
Dopamine (DA) is a neurotransmitter with actions across phylogeny that modulate core behaviors such as motor activity, reward, attention, and cognition. Perturbed DA signaling in humans is associated with multiple disorders, including addiction, ADHD, schizophrenia, and Parkinson's disease. The presynaptic DA transporter exerts powerful control on DA signaling by efficient clearance of the neurotransmitter following release. As in vertebrates, Caenorhabditis elegans DAT (DAT-1) constrains DA signaling and loss of function mutations in the dat-1 gene result in slowed crawling on solid media and swimming-induced paralysis (Swip) in water. Previously, we identified a mutant line, vt34, that exhibits robust DA-dependent Swip. vt34 exhibits biochemical and behavioral phenotypes consistent with reduced DAT-1 function though vt34; dat-1 double mutants exhibit an enhanced Swip phenotype, suggesting contributions of the vt34-associated mutation to additional mechanisms that lead to excess DA signaling. SNP mapping and whole genome sequencing of vt34 identified the site of the molecular lesion in the gene B0412.2 that encodes the Runx transcription factor ortholog RNT-1. Unlike dat-1 animals, but similar to other loss of function rnt-1 mutants, vt34 exhibits altered male tail morphology and reduced body size. Deletion mutations in both rnt-1 and the bro-1 gene, which encodes a RNT-1 binding partner also exhibit Swip. Both vt34 and rnt-1 mutations exhibit reduced levels of dat-1 mRNA as well as the tyrosine hydroxylase ortholog cat-2. Although reporter studies indicate that rnt-1 is expressed in DA neurons, its re-expression in DA neurons of vt34 animals fails to fully rescue Swip. Moreover, as shown for vt34, rnt-1 mutation exhibits additivity with dat-1 in generating Swip, as do rnt-1 and bro-1 mutations, and vt34 exhibits altered capacity for acetylcholine signaling at the neuromuscular junction. Together, these findings identify a novel role for rnt-1 in limiting DA neurotransmission and suggest that loss of RNT-1 may disrupt function of both DA neurons and body wall muscle to drive Swip.
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Affiliation(s)
- Sarah B Robinson
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN, United States of America
| | - Osama Refai
- Department of Biomedical Science, Charles E. Schmidt College of Science, Florida Atlantic University, Jupiter, FL United States of America
| | - J Andrew Hardaway
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN, United States of America
| | - Sarah Sturgeon
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN, United States of America
| | - Tessa Popay
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN, United States of America
| | - Daniel P Bermingham
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN, United States of America
| | - Phyllis Freeman
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN, United States of America
- Department of Life and Physical Sciences, Fisk University, Nashville, TN, United States of America
| | - Jane Wright
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN, United States of America
| | - Randy D Blakely
- Department of Biomedical Science, Charles E. Schmidt College of Science, Florida Atlantic University, Jupiter, FL United States of America
- Brain Institute, Florida Atlantic University, Jupiter, FL, United States of America
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17
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Kudumala S, Sossi S, Carvelli L. Swimming Induced Paralysis to Assess Dopamine Signaling in Caenorhabditis elegans. J Vis Exp 2019. [PMID: 31009010 DOI: 10.3791/59243] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
The swimming assay described in this protocol is a valid tool to identify proteins regulating the dopaminergic synapses. Similar to mammals, dopamine (DA) controls several functions in C. elegans including learning and motor activity. Conditions that stimulate DA release (e.g., amphetamine (AMPH) treatments) or that prevent DA clearance (e.g., animals lacking the DA transporter (dat-1) which are incapable of reaccumulating DA into the neurons) generate an excess of extracellular DA ultimately resulting in inhibited locomotion. This behavior is particularly evident when animals swim in water. In fact, while wild-type animals continue to swim for an extended period, dat-1 null mutants and wild-type treated with AMPH or inhibitors of the DA transporter sink to the bottom of the well and do not move. This behavior is termed "Swimming Induced Paralysis" (SWIP). Although the SWIP assay is well established, a detailed description of the method is lacking. Here, we describe a step-by-step guide to perform SWIP. To perform the assay, late larval stage-4 animals are placed in a glass spot plate containing control sucrose solution with or without AMPH. Animals are scored for their swimming behavior either manually by visualization under a stereoscope or automatically by recording with a camera mounted on the stereoscope. Videos are then analyzed using a tracking software, which yields a visual representation of thrashing frequency and paralysis in the form of heat maps. Both the manual and automated systems guarantee an easily quantifiable readout of the animals' swimming ability and thus facilitate screening for animals bearing mutations within the dopaminergic system or for auxiliary genes. In addition, SWIP can be used to elucidate the mechanism of action of drugs of abuse such as AMPH.
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Affiliation(s)
- Sirisha Kudumala
- Harriet Wilkes Honors College, Florida Atlantic University, John D MacArthur Campus
| | - Serena Sossi
- Integrative Biology and Neuroscience program, College of Science, Florida Atlantic University
| | - Lucia Carvelli
- Harriet Wilkes Honors College, Florida Atlantic University, John D MacArthur Campus; Brain Institute, Florida Atlantic University; Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University;
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