Name: a novel method to model chronic traumatic encephalopathy in drosophila
Uploaded: 2017-07-04T13:00:00.000+00:00
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Description: Watch this Scientific Journal Video about A Novel Method to Model Chronic Traumatic Encephalopathy in Drosophila at JoVE.com

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1. Montaggio del Dispositivo Strike ( Figura 1 ) <ol><li> Rimuovere lo stantuffo da una siringa tubercolina da 1 ml. Tagliare la canna al punto di 1 ml. </li><li> Rimuovere una barriera aerosol (3 mm di altezza x 4 mm di diametro) da una punta di pipetta da 200 μl e utilizzarla come impattatore. Posizionare l&#39;impatto nell&#39;interno della barra della siringa. Toccare delicatamente il cilindro per spostare l&#39;impattatore all&#39;estremità della punta, con il lato piatto che copre l&#39;apertura dell&#39;ugello. </li><li> Fissare l&#39;estremità della punta del tubo al tubo di plastica collegato al regolatore di flusso di anidride carbonica (CO 2 ) di una stazione di anestesia Drosophila . </li><li> Tenere la barella verticalmente e fissarla a un supporto di supporto standard di bloccaggio in modo che il dispositivo di impatto rimanga in fondo alla canna. </li><li> Modificare una punta pipetta da 200 μl per realizzare il supporto mosca. <ol><li> Tagliare 4 mm dalla punta per fare un&#39;apertura di diametro di 0,8 mm, consentendo solo di esporre la testa a mosca. NOTA: il thoRax e tutte le altre parti del corpo mosca rimarranno all&#39;interno della punta pipetta. </li></ol></li><li> Modificare una punta pipetta da 1000 μL e un tappo ago da 1 ml di siringa per realizzare il connettore. <ol><li> Tagliare 44 mm dall&#39;apertura della punta. Prendete una lunghezza di 6 mm di un capsula da 1 ml della siringa e spingetela strettamente nel segmento rimanente della punta della pipetta da 1000 μL. </li></ol></li></ol> 2. Funzionamento del dispositivo Strike <ol><li> Anestetizza una singola femmina adulta di 2 giorni che vola usando CO 2 su un moscerino. </li><li> Trasferitelo delicatamente sul supporto di mosca usando una spazzola fine. Toccare delicatamente il supporto in modo che la testa di mosca sia visibile all&#39;esterno dell&#39;estremità della punta. Se la proboscide di mosca è esposta al di fuori della punta, infilate leggermente dentro la punta con un ago sferico da 1 ml sbattuto. NOTA: Assicurarsi di mantenere la proboscide di mosca all&#39;interno del supporto. Altrimenti, la mosca può morire da un infortunio alla ventosa. </li><li> Serrare la moscaSulla barra della siringa con il connettore in modo che la testa di mosca sia rivolta verso il basso. </li><li> Impostare la pressione del gas a 100 kPa. Regolare la portata secondo il disegno dell&#39;esperimento. </li><li> Spostare e spegnere rapidamente l&#39;interruttore del regolatore di flusso in modo che l&#39;urto di impatto raggiunga una volta la testa di mosca. </li><li> Sollevare il supporto mosca e spostarlo su un rilievo di mosca. Invertire il supporto volante e toccare delicatamente il lato per far uscire il volo. Lasciare la mosca in un flacone vuoto per recuperare. </li></ol> 3. Monitoraggio del movimento assistito video <ol><li> Riempire un piatto di Petri da 6 cm con elastomero trasparente al silicio per realizzare l&#39;arena di tracciamento. Lasciare uno spazio di 3 mm tra il silicone e il coperchio del piatto per consentire alle mosche di camminare liberamente ma non di volare. </li><li> Anestetizzare quattro mosche dal gruppo o dal gruppo trattato ogni volta e piazzarli nell&#39;arena. Lasciare le mosche a 22 ° C per 1 ora. </li><li> Posizionare una telecamera con dispositivo di accoppiamento (CCD) sopra le arene e registrare per 5 minuti.</li><li> Analizzare le traiettorie di movimento registrate usando il software Ctrax (liberamente disponibile da Caltech) 16 . Esportare i dati tracciati in un linguaggio di programmazione (ad esempio, Matlab) -compatibile e analizzare i dati in base alla distanza percorsa per fotogramma 17 . Calcolare la distanza percorsa media per ogni mosca e combinarla con tutte le altre mosche registrate / gruppo per ottenere una distanza cumulativa media percorsa dalla popolazione di file nello stesso gruppo. </li></ol>

<ol>
	<li>McKee, A. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+first+NINDS/NIBIB+consensus+meeting+to+define+neuropathological+criteria+for+the+diagnosis+of+chronic+traumatic+encephalopathy.">The first NINDS/NIBIB consensus meeting to define neuropathological criteria for the diagnosis of chronic traumatic encephalopathy.</a> Acta Neuropathol. 131, 75-86 (2016).</li><li>Martland, H. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Punch+drunk.">Punch drunk.</a> JAMA. 91 (15), 1103-1107 (1928).</li><li>Millspaugh, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dementia+pugilistica.">Dementia pugilistica.</a> US Naval Med Bull. 35, 297-303 (1937).</li><li>Omalu, B. I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chronic+traumatic+encephalopathy+in+a+national+football+league+player:+part+II.">Chronic traumatic encephalopathy in a national football league player: part II.</a> Neurosurgery. 59 (5), 1086-1092 (2006).</li><li>Goldstein, L. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chronic+traumatic+encephalopathy+in+blast-exposed+military+veterans+and+a+blast+neurotrauma+mouse+model.">Chronic traumatic encephalopathy in blast-exposed military veterans and a blast neurotrauma mouse model.</a> Sci Transl Med. 4 (134), (2012).</li><li>Mez, J., Stern, R. A., McKee, A. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chronic+traumatic+encephalopathy:+where+are+we+and+where+are+we+going?.">Chronic traumatic encephalopathy: where are we and where are we going?.</a> Curr Neurol Neurosci Rep. 13 (12), 407 (2013).</li><li>McKee, A. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+spectrum+of+disease+in+chronic+traumatic+encephalopathy.">The spectrum of disease in chronic traumatic encephalopathy.</a> Brain. 136 (Pt 1), 43-64 (2013).</li><li>Petraglia, A. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+spectrum+of+neurobehavioral+sequelae+after+repetitive+mild+traumatic+brain+injury:+a+novel+mouse+model+of+chronic+traumatic+encephalopathy.">The spectrum of neurobehavioral sequelae after repetitive mild traumatic brain injury: a novel mouse model of chronic traumatic encephalopathy.</a> J Neurotrauma. 31 (13), 1211-1224 (2014).</li><li>Hirth, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Drosophila+melanogaster+in+the+study+of+human+neurodegeneration.">Drosophila melanogaster in the study of human neurodegeneration.</a> CNS Neurol Disord Drug Targets. 9 (4), 504-523 (2010).</li><li>Littleton, J. T., Ganetzky, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ion+channels+and+synaptic+organization:+analysis+of+the+Drosophila+genome.">Ion channels and synaptic organization: analysis of the Drosophila genome.</a> Neuron. 26 (1), 35-43 (2000).</li><li>Appel, L. F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Drosophila+Stubble-stubbloid+gene+encodes+an+apparent+transmembrane+serine+protease+required+for+epithelial+morphogenesis.">The Drosophila Stubble-stubbloid gene encodes an apparent transmembrane serine protease required for epithelial morphogenesis.</a> Proc Natl Acad Sci USA. 90 (11), 4937-4941 (1993).</li><li>Piyankarage, S. C., Featherstone, D. E., Shippy, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nanoliter+hemolymph+sampling+and+analysis+of+individual+adult+Drosophila+melanogaster.">Nanoliter hemolymph sampling and analysis of individual adult Drosophila melanogaster.</a> Anal Chem. 84 (10), 4460-4466 (2012).</li><li>Katzenberger, R. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Drosophila+model+of+closed+head+traumatic+brain+injury.">A Drosophila model of closed head traumatic brain injury.</a> Proc Natl Acad Sci USA. 110 (44), E4152-E4159 (2013).</li><li>Barekat, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Using+Drosophila+as+an+integrated+model+to+study+mild+repetitive+traumatic+brain+injury.">Using Drosophila as an integrated model to study mild repetitive traumatic brain injury.</a> Sci Rep. 6, 25252 (2016).</li><li>Katzenberger, R. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Method+to+Inflict+Closed+Head+Traumatic+Brain+Injury+in+Drosophila.">A Method to Inflict Closed Head Traumatic Brain Injury in Drosophila.</a> J Vis Exp. (e52905), (2015).</li><li>Branson, K., Robie, A. A., Bender, J., Perona, P., Dickinson, M. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-throughput+ethomics+in+large+groups+of+Drosophila.">High-throughput ethomics in large groups of Drosophila.</a> Nat Methods. 6 (6), 451-457 (2009).</li><li>Straw, A. D., Dickinson, M. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Motmot,+an+open-source+toolkit+for+realtime+video+acquisition+and+analysis.">Motmot, an open-source toolkit for realtime video acquisition and analysis.</a> Source Code Biol Med. 4 (5), 1-10 (2009).</li><li>Talavage, T. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functionally-detected+cognitive+impairment+in+high+school+football+players+without+clinically-diagnosed+concussion.">Functionally-detected cognitive impairment in high school football players without clinically-diagnosed concussion.</a> J Neurotrauma. 31 (4), 327-338 (2014).</li><li>Theadom, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Frequency+and+impact+of+recurrent+traumatic+brain+injury+in+a+population-based+sample.">Frequency and impact of recurrent traumatic brain injury in a population-based sample.</a> J Neurotrauma. 32 (10), 674-681 (2015).</li><li>Drobysheva, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+optimized+method+for+histological+detection+of+dopaminergic+neurons+in+Drosophila+melanogaster.">An optimized method for histological detection of dopaminergic neurons in Drosophila melanogaster.</a> J Histochem Cytochem. 56 (12), 1049-1063 (2008).</li></ol>

Questo lavoro è stato sostenuto dalla Facoltà di Johns Hopkins University School of Medicine di startup fund a LC

I modelli animali che modellano fedelmente le caratteristiche del CTE, comprese le alterazioni neurofisiologiche, i segni neuropatologici e i disordini neurobehaviorali, sono essenziali per scoprire i meccanismi della malattia e per sviluppare obiettivi diagnostici e terapeutici. È comprensibile che nessun modello animale di una malattia umana sia perfetto a imitare tutti gli endpoint clinicamente rilevanti. Tuttavia, riteniamo che un robusto modello CTE dovrebbe soddisfare i seguenti tre requisiti: (1) l&#39;impatto d...

L&#39;encefalopatia traumatica cronica (CTE) è stata recentemente riconosciuta come un disturbo neurodegenerativo distinto, separato da altre tauopatie come la malattia di Alzheimer 1 . A differenza della malattia di Alzheimer e di altre tauopatie comuni, i cui fattori di rischio più importanti stanno avanzando l&#39;età e una storia familiare di demenza, la CTE, come indicato dal suo nome, implica una stretta collaborazione con una storia di traumi cerebrali, probabilmente visto in atleti sportivi di contatto, Come pugili e calciatori, così come nei veterani militari 2 , 3 , 4 , 5 . Si pensa di essere iniziato da ripetuti colpi concussivi e subconcutici alla testa. I pazienti possono presentare sintomi e segni quali disordini cognitivi, cambiamenti di umore e comportamento e disfunzione di movimento, che si sovrappongono in modo significativo con la malattia di Alzheimer, frontotemporalDemenza, demenza del corpo di Lewy e malattia di Parkinson 6 . Al contrario, gli esami post-mortem del tessuto cerebrale rivelano un modello distinto di accumulo di tau per iperfosforilati che circonda i piccoli vasi sanguigni nelle profondità dei sulci corticali, caratteristica patognomonica non osservata nelle altre condizioni degenerative 7 . Tuttavia, finora poco si sa sulla patogenesi che conduce alla manifestazione delle malattie. Questo è in gran parte dovuto alla mancanza di un modello animale fedele - solo di recente sono stati generati modelli roditori 5 , 8 . Questi organismi di modello hanno gli svantaggi di una terapia intensiva e una durata di vita relativamente lunga, che non sono adatti per studi di malattia neurodegenerativa. Rispetto alle omologhe di mammiferi, gli animali invertebrati come Drosophila sono un&#39;ottima alternativa, con la loro manutenzione economica,Strumenti estensivi per la dissezione di determinanti genetici e durata relativamente breve 9 . Notevolmente, il cervello volante e umano condividono le vie molecolari e cellulari evolutamente conservate, nonché le somiglianze anatomiche 10 , 11 , 12 . Due geniali modelli Drosophila per studiare lesioni cerebrali traumatiche sono state riportate in precedenza 13 , 14 . Il primo dispositivo &quot;High Impact Trauma&quot; (HIT) progettato da Katzenberger e colleghi conteneva mosche in movimento in una flaconcina di plastica legata all&#39;estremità libera di una molla metallica 13 , 15 . Quando il flaconcino di plastica è stato inclinato in verticale e rilasciato, ha colpito un tampone di poliuretano e impartito il trauma alle mosche quando si sono rimbalzati alla parete del flacone e rimbalzato. Al contrario, Barekat e colleghi hanno progettato un diverso metodo di consegnaLa piattaforma omogeneizzatrice Omni Bead Ruptor-24 14 . Le mosche sono state inabilitate con CO 2 e poste in un tubo a vite da 2 mL che è stato fissato all&#39;omogenizzatore e sottoposto a condizioni di scossa preprogrammate. Un vantaggio di utilizzare il sistema di omogeneizzazione dei tessuti è che lo sperimentatore potrebbe modulare l&#39;intensità della lesione, la durata della lesione e il numero di attacchi di lesioni. Tuttavia, entrambi i regimi subiscono lo stesso inconveniente: lesioni primarie alla testa vengono inflitte casualmente in termini di posizione e forza di impatto. Inoltre, entrambi i metodi hanno determinato una notevole mortalità, causata da inevitabili danneggiamenti collaterali ad altre parti del corpo e degli organi interni. Qui descriviamo un nuovo metodo per indurre mTBI nelle mosche di frutta. Il nostro apparecchio è costituito da un impatto balistico a propulsione a gas. Rispetto ai modelli Drosophila 14 , 15 , il nostro metodo ha il vantaggio unico di fornire measImpatto urra, diretto solo alla testa di mosca libera, consentendo così il controllo accurato di vari fattori, come la gravità dell&#39;impatto, l&#39;intervallo di tempo tra gli impatti e il numero totale di impatti sostenuti.

<table><tbody><tr><td>Aerosol Barrier</td><td>USA Scientific</td><td>1120-8810</td><td>Used as an impactor</td></tr><tr><td>200 &amp;#956;L Pipette Tip</td><td>USA Scientific</td><td>1111-0706</td><td>Used as a fly head holder</td></tr><tr><td>1000 &amp;#956;L Pipette Tip</td><td>USA Scientific</td><td>1122-1830</td><td>Used as a connector</td></tr><tr><td>1 mL Tuberculin Syringe</td><td>Becton Dickinson</td><td>309625</td><td></td></tr><tr><td>60 mm Petri Dishes</td><td>Fisher Scientific</td><td>FB0875713A</td><td>Used as a tracking arenas</td></tr><tr><td>Flow Regulator</td><td>Genesee Scientific</td><td>59-122WC</td><td></td></tr><tr><td>Standard Clamp Holder/stand</td><td>EISCO Scientific</td><td>CH0688</td><td></td></tr><tr><td>Fine Brush</td><td>Genesee Scientific</td><td>59-204</td><td></td></tr><tr><td>Flypad</td><td>Genesee Scientific</td><td>59-114</td><td></td></tr><tr><td>Sylgard Silicone Elastomer</td><td>Dow Corning</td><td>4019862</td><td></td></tr><tr><td>CCD Camera</td><td>Microsoft&amp;nbsp;</td><td>HD-5000</td><td></td></tr><tr><td>Ctrax Walking Fly Tracker</td><td>Caltech</td><td>Ctrax 0.2.11</td><td></td></tr><tr><td>MATLAB Image Processing Toolbox</td><td>MATLAB</td><td>R2015b</td><td></td></tr></tbody></table>

a novel method to model chronic traumatic encephalopathy in drosophila

L&#39;encefalopatia traumatica cronica (CTE) è una malattia neurodegenerativa consolidata che è strettamente associata all&#39;esposizione a un mite traumatico (TMT) ripetitivo. I meccanismi responsabili dei suoi complessi cambiamenti patologici rimangono in gran parte sfuggenti, nonostante un recente consenso per definire i criteri neuropatologici. Qui descriviamo un nuovo metodo per sviluppare un modello di CTE in Drosophila melanogaster ( Drosophila ) nel tentativo di identificare i geni chiave e le vie che portano al caratteristico accumulo tau iperfosforilato e alla morte neuronale nel cervello. Impatti di forza di regolazione per infliggere lesioni chiuse lievi vengono consegnati direttamente alla testa di mosca sottoponendo la testa ad accelerazione e decelerazione rapida. Il nostro metodo elimina i problemi potenziali inerenti ad altri modelli moto Drosophila ( ad esempio, la morte animale potrebbe essere indotta da danni aAltre parti del corpo o agli organi interni). La mancanza di manodopera a basso costo e a basso costo, una breve durata di vita e estesi strumenti genetici rendono la frutta ideale per studiare la patogenesi della CTE e rendere possibile la realizzazione di schermi genetici e farmacologici avanzati su vasta scala genomica. Prevediamo che la continua caratterizzazione del modello genera importanti conoscenze meccaniche sulla prevenzione delle malattie e sugli approcci terapeutici.

Per stabilire un modello CTE con l&#39;adulto Drosophila abbiamo determinato l&#39;efficacia del nostro dispositivo per infliggere una singola lesione alla testa chiusa. Per eliminare le variazioni relative al genotipo, al sesso o all&#39;età, abbiamo usato le mosche femminili Canton-S WT di due giorni nell&#39;esperimento. Potremmo facilmente controllare la resistenza dell&#39;impulso di impatto regolando la portata di CO 2 ad una pressione costante di 100 kPa. Le m...

Watch this Scientific Journal Video about A Novel Method to Model Chronic Traumatic Encephalopathy in Drosophila at JoVE.com

A Novel Method to Model Chronic Traumatic Encephalopathy in Drosophila

Qui descriviamo un nuovo approccio per infliggere danni traumatici al cervello chiuso a Drosophila melanogaster . Il nostro metodo ha il vantaggio di trasmettere direttamente impatti ripetitivi con forza regolabile solo alla testa. Un&#39;ulteriore esplorazione del sistema invertebrato contribuirà ad illuminare la patogenesi di encefalopatia traumatica cronica.

Un nuovo metodo per modellare l&#39;encefalopatia traumatica cronica in<em&gt; Drosophila</em

Chronic Traumatic Encephalopathy (CTE) is an established neurodegenerative disease that is closely associated with exposure to repetitive mild Traumatic ...

a-novel-method-to-model-chronic-traumatic-encephalopathy-in-drosophila

Research

JoVE Journal

Neuroscience

A Novel Method to Model Chronic Traumatic Encephalopathy in Drosophila

8.2K Views.  Johns Hopkins University School of Medicine.  Qui descriviamo un nuovo approccio per infliggere danni traumatici al cervello chiuso a Drosophila melanogaster . Il nostro metodo ha il vantaggio di trasmettere direttamente impatti ripetitivi con forza regolabile solo alla testa. Un'ulteriore esplorazione del sistema invertebrato contribuirà ad illuminare la patogenesi di encefalopatia traumatica cronica. 

Video: A Novel Method to Model Chronic Traumatic Encephalopathy in Drosophila

Assaying Locomotor, Learning, and Memory Deficits in Drosophila Models of Neurodegeneration

Advances in genetic methods have enabled the study of genes involved in human neurodegenerative diseases using Drosophila as a model system1. Most of these diseases, including Alzheimer's, Parkinson's and Huntington's disease are characterized by age-dependent deterioration in learning and memory functions and movement coordination2. Here we use behavioral assays, including the negative geotaxis assay3 and the aversive phototaxic suppression assay (APS assay)4,5, to show that some of the behavior characteristics associated with human neurodegeneration can be recapitulated in flies. In the negative geotaxis assay, the natural tendency of flies to move against gravity when agitated is utilized to study genes or conditions that may hinder locomotor capacities. In the APS assay, the learning and memory functions are tested in positively-phototactic flies trained to associate light with aversive bitter taste and hence avoid this otherwise natural tendency to move toward light. Testing these trained flies 6 hours post-training is used to assess memory functions. Using these assays, the contribution of any genetic or environmental factors toward developing neurodegeneration can be easily studied in flies.

Assaying Locomotor, Learning, and Memory Deficits in Drosophila Models of Neurodegeneration

Behavior assays for measuring locomotor functions, learning, and memory abilities in Drosophila.

Deficit Locomotore dosaggio, apprendimento e memoria in Drosophila Modelli di neurodegenerazione

Advances in genetic methods have enabled the study of genes involved in human neurodegenerative diseases using Drosophila as a model system1. Most of ...

Ricerca

Neuroscienze

Dissection and Immunofluorescent Staining of Mushroom Body and Photoreceptor Neurons in Adult Drosophila melanogaster Brains

Nervous system development involves a sequential series of events that are coordinated by several signaling pathways and regulatory networks. Many of the proteins involved in these pathways are evolutionarily conserved between mammals and other eukaryotes, such as the fruit fly Drosophila melanogaster, suggesting that similar organizing principles exist during the development of these organisms. Importantly, Drosophila has been used extensively to identify cellular and molecular mechanisms regulating processes that are required in mammals including neurogenesis, differentiation, axonal guidance, and synaptogenesis. Flies have also been used successfully to model a variety of human neurodevelopmental diseases. Here we describe a protocol for the step-by-step microdissection, fixation, and immunofluorescent localization of proteins within the adult Drosophila brain. This protocol focuses on two example neuronal populations, mushroom body neurons and retinal photoreceptors, and includes optional steps to trace individual mushroom body neurons using Mosaic Analysis with a Repressible Cell Marker (MARCM) technique. Example data from both wild-type and mutant brains are shown along with a brief description of a scoring criteria for axonal guidance defects. While this protocol highlights two well-established antibodies for investigating the morphology of mushroom body and photoreceptor neurons, other Drosophila brain regions and the localization of proteins within other brain regions can also be investigated using this protocol.

Dissection and Immunofluorescent Staining of Mushroom Body and Photoreceptor Neurons in Adult Drosophila melanogaster Brains

This protocol describes the dissection and immunostaining of adult Drosophila melanogaster brain tissues. Specifically, this protocol highlights the use of Drosophila mushroom body and photoreceptor neurons as example neuronal subsets that can be accurately used to uncover general principles underlying many aspects of neuronal development.

Dissezione e macchiatura immunofluorescente del corpo di fungo e del fotoricettore neuroni nel cervello adulto Drosophila melanogaster

Nervous system development involves a sequential series of events that are coordinated by several signaling pathways and regulatory networks. Many of the ...

Biologia dello sviluppo

Assessing Neurodegenerative Phenotypes in Drosophila Dopaminergic Neurons by Climbing Assays and Whole Brain Immunostaining

Drosophila melanogaster is a valuable model organism to study aging and pathological degenerative processes in the nervous system. The advantages of the fly as an experimental system include its genetic tractability, short life span and the possibility to observe and quantitatively analyze complex behaviors. The expression of disease-linked genes in specific neuronal populations of the Drosophila brain, can be used to model human neurodegenerative diseases such as Parkinson's and Alzheimer's 5.
Dopaminergic (DA) neurons are among the most vulnerable neuronal populations in the aging human brain. In Parkinson's disease (PD), the most common neurodegenerative movement disorder, the accelerated loss of DA neurons leads to a progressive and irreversible decline in locomotor function. In addition to age and exposure to environmental toxins, loss of DA neurons is exacerbated by specific mutations in the coding or promoter regions of several genes. The identification of such PD-associated alleles provides the experimental basis for the use of Drosophila as a model to study neurodegeneration of DA neurons in vivo. For example, the expression of the PD-linked human &alpha;-synuclein gene in Drosophila DA neurons recapitulates some features of the human disease, e.g. progressive loss of DA neurons and declining locomotor function 2. Accordingly, this model has been successfully used to identify potential therapeutic targets in PD 8.
Here we describe two assays that have commonly been used to study age-dependent neurodegeneration of DA neurons in Drosophila: a climbing assay based on the startle-induced negative geotaxis response and tyrosine hydroxylase immunostaining of whole adult brain mounts to monitor the number of DA neurons at different ages. In both cases, in vivo expression of UAS transgenes specifically in DA neurons can be achieved by using a tyrosine hydroxylase (TH) promoter-Gal4 driver line 3, 10.

Assessing Neurodegenerative Phenotypes in Drosophila Dopaminergic Neurons by Climbing Assays and Whole Brain Immunostaining

Here we describe two assays that have been established to study age-dependent neurodegeneration of dopaminergic (DA) neurons in Drosophila: the climbing/startle-induced negative geotaxis assay which allows to study the functional effects of DA neurons degeneration and the tyrosine hydroxylase immunostaining which is used to identify and count DA neurons in whole brain mounts.

Valutare fenotipi neurodegenerative<em&gt; Drosophila</em&gt; Neuroni dopaminergici mediante saggi arrampicata e Whole Brain Immunostaining

Drosophila melanogaster is a valuable model organism to study aging and pathological degenerative processes in the nervous system. The advantages of the ...

Quantitative Analysis of Climbing Defects in a Drosophila Model of Neurodegenerative Disorders

Locomotive defects resulting from neurodegenerative disorders can be a late onset symptom of disease, following years of subclinical degeneration, and thus current therapeutic treatment strategies are not curative. Through the use of whole exome sequencing, an increasing number of genes have been identified to play a role in human locomotion. Despite identifying these genes, it is not known how these genes are crucial to normal locomotive functioning. Therefore, a reliable assay, which utilizes model organisms to elucidate the role of these genes in order to identify novel targets of therapeutic interest, is needed more than ever. We have designed a sensitized version of the negative geotaxis assay that allows for the detection of milder defects earlier and has the ability to evaluate these defects over time. The assay is performed in a glass graduated cylinder, which is sealed with a wax barrier film. By increasing the threshold distance to be climbed to 17.5 cm and increasing the experiment duration to 2 min&#160;we have observed a greater sensitivity in detecting mild mobility dysfunctions. The assay is cost effective and does not require extensive training to obtain highly reproducible results. This makes it an excellent technique for screening candidate drugs in Drosophila mutants with locomotion defects.

We present an optimized inexpensive and reliable negative geotaxis assay in Drosophila melanogaster as a model for neurodegenerative disorders. Being more sensitive to mild locomotor defects, this assay will help screen for potential genetic interactions and drug targets.

Analisi quantitativa dei difetti arrampicata in un modello Drosophila di malattie neurodegenerative

Locomotive defects resulting from neurodegenerative disorders can be a late onset symptom of disease, following years of subclinical degeneration, and ...

A Method to Inflict Closed Head Traumatic Brain Injury in Drosophila

Traumatic brain injury (TBI) affects millions of people each year, causing impairment of physical, cognitive, and behavioral functions and death. Studies using Drosophila have contributed important breakthroughs in understanding neurological processes. Thus, with the goal of understanding the cellular and molecular basis of TBI pathologies in humans, we developed the High Impact Trauma (HIT) device to inflict closed head TBI in flies. Flies subjected to the HIT device display phenotypes consistent with human TBI such as temporary incapacitation and progressive neurodegeneration. The HIT device uses a spring-based mechanism to propel flies against the wall of a vial, causing mechanical damage to the fly brain. The device is inexpensive and easy to construct, its operation is simple and rapid, and it produces reproducible results. Consequently, the HIT device can be combined with existing experimental tools and techniques for flies to address fundamental questions about TBI that can lead to the development of diagnostics and treatments for TBI. In particular, the HIT device can be used to perform large-scale genetic screens to understand the genetic basis of TBI pathologies.

A Method to Inflict Closed Head Traumatic Brain Injury in Drosophila

Here we describe a method to inflict closed head traumatic brain injury (TBI) in Drosophila. This method provides a gateway to investigate the cellular and molecular mechanisms that underlie TBI pathologies using the vast array of experimental tools and techniques available for flies.

Un metodo per infliggere Chiuso Testa trauma cranico in<em&gt; Drosophila</em

Traumatic brain injury (TBI) affects millions of people each year, causing impairment of physical, cognitive, and behavioral functions and death. Studies ...

Mass Histology to Quantify Neurodegeneration in Drosophila

Progressive neurodegenerative diseases like Alzheimer&#39;s disease (AD) or Parkinson&#39;s disease (PD) are an increasing threat to human health worldwide. Although mammalian models have provided important insights into the underlying mechanisms of pathogenicity, the complexity of mammalian systems together with their high costs are limiting their use. Therefore, the simple but well-established Drosophila model-system&#160;provides an alternative for investigating the molecular pathways that are affected in these diseases. Besides behavioral deficits, neurodegenerative diseases are characterized by histological phenotypes such as neuronal death and axonopathy. To quantify neuronal degeneration and to determine how it is affected by genetic and environmental factors, we use a histological approach that is based on measuring the vacuoles in adult fly brains. To minimize the effects of systematic error and to directly compare sections from control and experimental flies in one preparation, we use the &#39;collar&#39; method for paraffin sections. Neurodegeneration is then assessed by measuring the size and/or number of vacuoles that have developed in the fly brain. This can either be done by focusing on a specific region of interest or by analyzing the entire brain by obtaining serial sections that span the complete head. Therefore, this method allows one to measure not only severe degeneration but also relatively mild phenotypes that are only detectable in a few sections, as occurs during normal aging.

Mass Histology to Quantify Neurodegeneration in Drosophila

Drosophila is widely used as a model system to study neurodegeneration. This protocol describes a method by which degeneration, as determined by vacuole formation in the brain, can be quantified. It also minimizes effects due to the experimental procedure by processing and sectioning control and experimental flies as one sample.

Messa Istologia per quantificare neurodegenerazione in<em&gt; Drosophila</em

Progressive neurodegenerative diseases like Alzheimer&#39;s disease (AD) or Parkinson&#39;s disease (PD) are an increasing threat to human health ...

Purification of Transcripts and Metabolites from Drosophila Heads

For the last decade, we have tried to understand the molecular and cellular mechanisms of neuronal degeneration using Drosophila as a model organism. Although fruit flies provide obvious experimental advantages, research on neurodegenerative diseases has mostly relied on traditional techniques, including genetic interaction, histology, immunofluorescence, and protein biochemistry. These techniques are effective for mechanistic, hypothesis-driven studies, which lead to a detailed understanding of the role of single genes in well-defined biological problems. However, neurodegenerative diseases are highly complex and affect multiple cellular organelles and processes over time. The advent of new technologies and the omics age provides a unique opportunity to understand the global cellular perturbations underlying complex diseases. Flexible model organisms such as Drosophila are ideal for adapting these new technologies because of their strong annotation and high tractability. One challenge with these small animals, though, is the purification of enough informational molecules (DNA, mRNA, protein, metabolites) from highly relevant tissues such as fly brains. Other challenges consist of collecting large numbers of flies for experimental replicates (critical for statistical robustness) and developing consistent procedures for the purification of high-quality biological material. Here, we describe the procedures for collecting thousands of fly heads and the extraction of transcripts and metabolites to understand how global changes in gene expression and metabolism contribute to neurodegenerative diseases. These procedures are easily scalable and can be applied to the study of proteomic and epigenomic contributions to disease.

Purification of Transcripts and Metabolites from Drosophila Heads

We describe here the procedures for the extraction and purification of mRNA and metabolites from Drosophila heads. We are applying these techniques to better understand the cellular perturbations underlying neuronal degeneration. These methodologies can be easily scaled and adapted for other "omic" projects.

Purificazione di Trascrizioni e metaboliti<em&gt; Drosophila</em&gt; Teste

For the last decade, we have tried to understand the molecular and cellular mechanisms of neuronal degeneration using Drosophila as a model organism. ...

Biologia

Morphological and Functional Evaluation of Axons and their Synapses during Axon Death in Drosophila melanogaster

Axon degeneration is a shared feature in neurodegenerative disease and when nervous systems are challenged by mechanical or chemical forces. However, our understanding of the molecular mechanisms underlying axon degeneration remains limited. Injury-induced axon degeneration serves as a simple model to study how severed axons execute their own disassembly (axon death). Over recent years, an evolutionarily conserved axon death signaling cascade has been identified from flies to mammals, which is required for the separated axon to degenerate after injury. Conversely, attenuated axon death signaling results in morphological and functional preservation of severed axons and their synapses. Here, we present three simple and recently developed protocols that allow for the observation of axonal morphology, or axonal and synaptic function of severed axons that have been cut-off from the neuronal cell body, in the fruit fly Drosophila. Morphology can be observed in the wing, where a partial injury results in axon death side-by-side of uninjured control axons within the same nerve bundle. Alternatively, axonal morphology can also be observed in the brain, where the whole nerve bundle undergoes axon death triggered by antennal ablation. Functional preservation of severed axons and their synapses can be assessed by a simple optogenetic approach coupled with a post-synaptic grooming behavior. We present examples using a highwire loss-of-function mutation and by over-expressing dnmnat, both capable of delaying axon death for weeks to months. Importantly, these protocols can be used beyond injury; they facilitate the characterization of neuronal maintenance factors, axonal transport, and axonal mitochondria.

Morphological and Functional Evaluation of Axons and their Synapses during Axon Death in Drosophila melanogaster

Here, we provide protocols to perform three simple injury-induced axon degeneration (axon death) assays in Drosophila melanogaster to evaluate the morphological and functional preservation of severed axons and their synapses.

Valutazione morfologica e funzionale degli assoni e delle loro sinapsi durante la morte di Axon in Drosophila melanogaster

Axon degeneration is a shared feature in neurodegenerative disease and when nervous systems are challenged by mechanical or chemical forces. However, our ...

Tracking Freely Walking Flies: A Method to Assess Locomotion in Drosophila

Source: Sun, M. and Chen, L. L. <a href="https://www.jove.com/video/55602/" target="_blank">A Novel Method to Model Chronic Traumatic Encephalopathy in Drosophila</a>. J. Vis. Exp. (2017).
This video describes how to track freely walking flies to assess their general locomotion ability. The featured protocol demonstrates the assay&#39;s setup and data analysis using video tracking software.

Tracciare le mosche che camminano liberamente: un metodo per valutare la locomozione in Drosophila

Source: Sun, M. and Chen, L. L. A Novel Method to Model Chronic Traumatic Encephalopathy in Drosophila. J. Vis. Exp. (2017).
This video describes how to ...

JoVE Encyclopedia of Experiments

Drosophila melanogaster (fruit fly)

Adult

A Technique to Inflict Closed-Head Traumatic Brain Injury in Drosophila Flies

Source: Sun, M., et al. <a href="https://app.jove.com/v/55602">A Novel Method to Model Chronic Traumatic Encephalopathy in Drosophila.</a> J. Vis. Exp. (2017).
This video demonstrates a procedure to inflict a closed-head traumatic injury in anesthetized Drosophila flies using a strike device with a gas-propelled impactor. The injury affects neuronal function and impairs walking ability.

Una tecnica per infliggere una lesione cerebrale traumatica a testa chiusa nelle mosche della Drosophila

1. Assembly of the Strike Device (Figure 1)

	Remove the plunger from a 1 mL tuberculin syringe. Cut the barrel at the 1 mL mark.
	Remove an aerosol ...

Un nuovo metodo per modellare l'encefalopatia traumatica cronica in

Riepilogo

Esplora Altri Video

Capitoli in questo video

Deficit Locomotore dosaggio, apprendimento e memoria in Drosophila Modelli di neurodegenerazione

Dissezione e macchiatura immunofluorescente del corpo di fungo e del fotoricettore neuroni nel cervello adulto Drosophila melanogaster

Valutare fenotipi neurodegenerative

Analisi quantitativa dei difetti arrampicata in un modello Drosophila di malattie neurodegenerative

Un metodo per infliggere Chiuso Testa trauma cranico in

Messa Istologia per quantificare neurodegenerazione in

Purificazione di Trascrizioni e metaboliti

Valutazione morfologica e funzionale degli assoni e delle loro sinapsi durante la morte di Axon in Drosophila melanogaster

Tracciare le mosche che camminano liberamente: un metodo per valutare la locomozione in Drosophila

Una tecnica per infliggere una lesione cerebrale traumatica a testa chiusa nelle mosche della Drosophila