Il lavoro qui descritto è stato finanziato dal US Department of Veterans Affairs Laboratorio Biomedico di Ricerca e Sviluppo BX001686-1A1 e VA Riabilitazione Ricerca e Sviluppo.

1. Placcatura e la conservazione della cultura cellulare <ol><li> Scaldano Dulbecco Modified Eagle Medium (DMEM) terreni di coltura (DMEM + 10% FBS + 1% di penicillina / streptomicina / neomicina) a 37 ° C. </li><li> Ottenere magazzino di surgelati A12 cellule da -80 ° C. </li><li> Rapidamente scongelare le cellule in 37 ° C a bagnomaria; una volta scongelato, delicatamente le cellule pipetta di trasferire a un pallone di coltura ventilato 75 centimetri 2 e aggiungere 10 ml di coltura. </li><li> Incubare pallone pernottamento in 5% CO 2 incubatore a 37 ° C. Aspirare il terreno dopo 24 ore e sostituirlo con mezzi freschi. Continuare a crescere le cellule fino ad ottenere il 70-80% di confluenza (2-3 giorni di crescita). </li></ol> 2. Conteggio e placcatura Celle <ol><li> DMEM Caldo e soluzione 1x-tripsina-EDTA a 37 ° C. </li><li> Aspirare supporti dalle cellule e lavare due volte con fosfato sterile salina tamponata (PBS). </li><li> Aggiungere 500 microlitri di soluzione di tripsina e incubare a 37 ° C per 2-5 min. </li><li> Distaccarecellule da matraccio con una spatola e sospendere le cellule in 5 ml di media. Passare cellule attraverso il filtro e passare attraverso il filtro delle cellule in una provetta pulita da 50 ml. Potrebbe essere necessario passare cellule attraverso il filtro più di una volta, ma non ripetere più di tre volte. </li><li> Contare le cellule utilizzando un emocitometro per determinare quantità di cellule di coltura per seminare 6.000 cellule / pozzetto in 96 pozzetti trasparente fondo nero o bianco piastra murato in un volume finale di 100 microlitri di media. Incubare la piastra in 5% CO 2 a 37 ° C per 24 ore. </li></ol> 3. Determinare la vitalità delle cellule e caspasi-3/7 Attività <ol><li> Trasferire PA ad una sterile 5 ml fiala di vetro e solubilizzare in 100% dimetilsolfossido (DMSO). Diluire soluzione stock PA 1:10 in DMSO e aggiungerlo al preriscaldata DMEM per ottenere una concentrazione finale di lavoro di 0.1 PA mm. Per i mezzi di controllo, aggiungere la stessa concentrazione di DMSO che viene aggiunto a supporti contenenti PA. </li><li> Rimuovere il supporto in ciascun pozzetto e sostituire con 50 mezzi microlitri + / -PA. Incubare la piastra per 2 h in 5% CO 2 a 37 ° C. Aggiungere quindi 5 ml resazurina reagenti e incubare per 10 minuti a temperatura ambiente. </li><li> Utilizzando un lettore di micropiastre multimodale, record di fluorescenza (560 EX / 590 EM) per misurare la vitalità cellulare. I risultati sono presentati come unità di fluorescenza relativa (RFU). </li><li> Per la stessa piastra, aggiungere 55 ml di reagente caspasi e incubare a temperatura ambiente per 2 ore. </li><li> Anche in questo caso utilizzando il lettore per micropiastre, record di luminescenza per misurare l&#39;attività della caspasi-3/7. I risultati sono presentati come unità di luminescenza relativa (RLU), con luminescenza direttamente proporzionale alla caspasi-3/7 attività. </li><li> Per normalizzare l&#39;attività della caspasi-3/7 per il conteggio delle cellule, dividere vitalità cellulare (RFU) da caspasi-3/7 attività (RLU). </li></ol>

<ol>
	<li>Akil, L., Ahmad, H. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Relationships+between+obesity+and+cardiovascular+diseases+in+four+southern+states+and+Colorado.">Relationships between obesity and cardiovascular diseases in four southern states and Colorado.</a> J. Health Care Poor Underserved. 22, 61-72 (2011).</li><li>Posey, K. 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=Hypothalamic+proinflammatory+lipid+accumulation,+inflammation,+and+insulin+resistance+in+rats+fed+a+high-fat+diet.">Hypothalamic proinflammatory lipid accumulation, inflammation, and insulin resistance in rats fed a high-fat diet.</a> Am. J. Physiol. Endocrinol. Metab. 296, 1003-1012 (2009).</li><li>Moraes, J. 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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=Palmitic+acid+mediates+hypothalamic+insulin+resistance+by+altering+PKC-theta+subcellular+localization+in+rodents.">Palmitic acid mediates hypothalamic insulin resistance by altering PKC-theta subcellular localization in rodents.</a> J. Clin. Invest. 119, 2577-2589 (2009).</li><li>Thaler, J. P., 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=Obesity+is+associated+with+hypothalamic+injury+in+rodents+and+humans.">Obesity is associated with hypothalamic injury in rodents and humans.</a> J. Clin. Invest. 122, 153-162 (2012).</li><li>Williams, L. 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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=Generation+of+a+phenotypic+array+of+hypothalamic+neuronal+cell+models+to+study+complex+neuroendocrine+disorders.">Generation of a phenotypic array of hypothalamic neuronal cell models to study complex neuroendocrine disorders.</a> Endocrinology. 145, 393-400 (2004).</li><li>Xiao, 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=Monitoring+of+cell+viability+and+proliferation+in+hydrogel-encapsulated+system+by+resazurin+assay.">Monitoring of cell viability and proliferation in hydrogel-encapsulated system by resazurin assay.</a> Appl. Biochem. Biotechnol. 162, 1996-2007 (2010).</li><li>Butterick, T. A., Nixon, J. P., Billington, C. J., Kotz, C. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Orexin+A+decreases+lipid+peroxidation+and+apoptosis+in+a+novel+hypothalamic+cell+model.">Orexin A decreases lipid peroxidation and apoptosis in a novel hypothalamic cell model.</a> Neurosci. Lett. 524, 30-34 (2012).</li><li>Riss, T. L., Moravec, R. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+multiple+assay+endpoints+to+investigate+the+effects+of+incubation+time,+dose+of+toxin,+and+plating+density+in+cell-based+cytotoxicity+assays.+Assay+Drug+Dev.">Use of multiple assay endpoints to investigate the effects of incubation time, dose of toxin, and plating density in cell-based cytotoxicity assays. Assay Drug Dev.</a> Technol. 2, 51-62 (2004).</li><li>Niles, A. L., Moravec, R. A., Riss, T. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+viability+and+cytotoxicity+testing+and+same-well+multi-parametric+combinations+for+high+throughput+screening.">In vitro viability and cytotoxicity testing and same-well multi-parametric combinations for high throughput screening.</a> Curr. Chem. Genomics. 3, 33-41 (2009).</li><li>Steffen, W., Linck, R. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multiple+immunoblot:+a+sensitive+technique+to+stain+proteins+and+detect+multiple+antigens+on+a+single+two-dimensional+replica.">Multiple immunoblot: a sensitive technique to stain proteins and detect multiple antigens on a single two-dimensional replica.</a> Electrophoresis. 10, 714-718 (1989).</li><li>Gingrich, J. C., Davis, D. R., Nguyen, Q. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multiplex+detection+and+quantitation+of+proteins+on+western+blots+using+fluorescent+probes.">Multiplex detection and quantitation of proteins on western blots using fluorescent probes.</a> Biotechniques. 29, 636-642 (2000).</li><li>Riss, T. L., Moravec, R. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+multiple+assay+endpoints+to+investigate+the+effects+of+incubation+time,+dose+of+toxin,+and+plating+density+in+cell-based+cytotoxicity+assays.">Use of multiple assay endpoints to investigate the effects of incubation time, dose of toxin, and plating density in cell-based cytotoxicity assays.</a> Assay Drug Dev. Technol. 2, 51-62 (2004).</li><li>Smyth, P. G., Berman, 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=Markers+of+apoptosis:+methods+for+elucidating+the+mechanism+of+apoptotic+cell+death+from+the+nervous+system.">Markers of apoptosis: methods for elucidating the mechanism of apoptotic cell death from the nervous system.</a> Biotechniques. 32, 648-650 (2002).</li><li>Lavrik, I. N., Golks, A., Krammer, P. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Caspases:+pharmacological+manipulation+of+cell+death.">Caspases: pharmacological manipulation of cell death.</a> J. Clin. Invest. 115, 2665-2672 (2005).</li></ol>

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Il saggio multiplex è una tecnica ben accettato che è stato usato dagli scienziati in numerose applicazioni come PCR, microarrays immunodetezione e altri metodi di rilevamento a base di proteine ​​13, 14. Recentemente, saggi multiplexing sono diventati sempre più utilizzato in vitro esperimenti basati piatto-in e sono stati convalidati come un metodo accurato per valutare la citotossicità e la vitalità 12. Nel protocollo di cui sopra, abbiamo dimostrato l&#39;efficacia di...

Le diete ricche di acidi grassi saturi come l&#39;acido palmitico (PA) sono state legate a obesità e altre patologie concomitanti, tra cui le malattie cardiovascolari e il diabete 1, 2. Diete ricche di grassi hanno anche dimostrato di aumentare lo stress ossidativo, apoptosi, e la degenerazione neuronale nell&#39;ipotalamo, un importante regolatore di appetito e il dispendio energetico 3-7. Comprendere il meccanismo attraverso il quale l&#39;esposizione dieta ricca di grassi induce disregolazione ipotalamo è quindi importante per lo sviluppo di trattamenti farmacologici per l&#39;obesità. Tuttavia, i meccanismi cellulari attraverso i quali i grassi alimentari colpisce la funzione neuronale rimangono poco chiari. Una migliore comprensione di come grassi come PA potrebbero innescare insorgenza di vie apoptotiche ipotalamici è necessario un primo passo verso questo obiettivo. L&#39;obiettivo di questo articolo è quello di descrivere un saggio multiplex per la sperimentazione in vitro di risposta neuronale all&#39;esposizione PA, sviluppato per l&#39;uso in studi di hneurodegenerazione ypothalamic. Forniamo una descrizione dettagliata di un formato a 96 pozzetti test multiplex in vitro per la misurazione della caspasi 3/7 attività per numero totale di celle in una linea differenziata immortalato topo adulto ipotalamico cellulare (designato A12) dopo la sfida ossidativo con PA 8. In breve, la vitalità cellulare è determinata a seguito PA sfida con un saggio resazurina based. Resazurin è un composto permeabile cella subisce una riduzione enzimatica in cellule metabolicamente attive, un processo pensato avvenga tramite mitocondri 9. Cellule vitali continuamente convertono resazurin a resorufina, producendo un segnale fluorescente proporzionale al numero di cellule vitali. L&#39;attività della caspasi-3/7 viene poi analizzata utilizzando un saggio basato lumogenic-DEVD. DEVD è una sequenza amminoacidica (Asp-Glu-Val-Asp) spaccati da caspasi-3. Quando questa sequenza è accoppiato ad una sostanza lumogenic, previa attivazione di intracellulare caspasi-3/7 e successiva scissionedi substrato DEVD, il prodotto luminescente viene rilasciato. Questa reazione è proporzionale all&#39;attività caspasi e quindi l&#39;induzione di apoptosi. Poiché le cellule morte non possono produrre caspasi, caspasi-3/7 attività è per sua natura transitoria; pertanto, l&#39;analisi deve essere completata tra 30 minuti e 4 ore post-sfida, a seconda dell&#39;efficacia delle stressor cellulare. La vitalità cellulare è inversamente proporzionale all&#39;attività caspasi-3/7 e può essere utilizzato per determinare meccanismi della morte cellulare. Ad esempio, questo metodo è già stata utilizzata per dimostrare che il pretrattamento con l&#39;ormone peptidico orexina riduce l&#39;apoptosi in cellule ipotalamiche stimolate con perossido di idrogeno, suggerendo che meccanismi interessate da questo trattamento sono importanti per proteggere dai danni ossidativi 10. È importante notare questi saggi sono linea-e cellule tessuto-dipendente, in quanto si basano su attività mitocondriale per ridurre i reagenti del saggio. Questo protocollo è stato ottimizzato per topo adulto ipotalamico (A12), le cellule; tuttavia,metodi descritti possono essere modificate per adattarsi nell&#39;ambito di ricerche simili. Multiplexing saggi di un&#39;unica cultura fornisce anche un vantaggio rispetto al metodo tradizionale di eseguire dosaggi individuali per diversi motivi. Oltre al risparmio di tempo, campioni di cellule e reagenti cultura, saggi di multiplazione possono anche fornire conoscenze della sopravvivenza cellulare e morte, fornire controlli interni, ed eliminare la necessità di esperimenti ripetitivi 11, 12. Metodi alternativi hanno invocato macchie o ELISA occidentali, che sono test affidabili, ma sono costosi e che richiede tempo (1-2 giorni), soprattutto quando si utilizza un formato a 96 pozzetti. Escludendo il tempo necessario per le cellule di coltura per il saggio multiplexing, il tempo totale è meno di 3 ore. Mentre questo protocollo è stato ottimizzato per l&#39;uso con A12 cellule, può essere modificato per l&#39;utilizzo in altri modelli tenendo a mente fattori che possono influenzare l&#39;integrità delle cellule. Scoraggiareestrazione se questo protocollo funzionerebbe per una serie di esperimenti dipende dal numero di campioni o condizioni sperimentali e su esperimenti valle pianificati.

<table border="0" cellpadding="0" cellspacing="0" width="723">
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:268px;">Adult Mouse Hypothalamus Cell Line mHypoA-1/2&#160;</td>
			<td style="width:137px;">Cellutions Biosystems Inc.</td>
			<td style="width:151px;">CLU172</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:268px;">Dulbecco&#8217;s Modified Eagle&#8217;s Medium</td>
			<td style="width:137px;">Invitrogen</td>
			<td style="width:151px;">10313-039</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:268px;">Fetal bovine serum&#160;</td>
			<td style="width:137px;">PAA Labs</td>
			<td style="width:151px;">A15-751</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:268px;">Penicillin/Streptomycin</td>
			<td style="width:137px;">Invitrogen</td>
			<td style="width:151px;">15070-063</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:268px;">Palmitic Acid</td>
			<td style="width:137px;">Sigma-Aldrich</td>
			<td style="width:151px;">P0500</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:268px;">Dimethy sulfoxide&#160;</td>
			<td style="width:137px;">Sigma-Aldrich</td>
			<td style="width:151px;">D2650</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:268px;"> 
			PrestoBlue Cell Viability Reagent</td>
			<td style="width:137px;">Invitrogen</td>
			<td>A13262</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:268px;">Caspase-Glo 3/7 Assay Systems</td>
			<td style="width:137px;">Promega</td>
			<td style="width:151px;">G8091</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:268px;">Equipment</td>
			<td style="width:137px;"></td>
			<td style="width:151px;"></td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:268px;">96W Optical Bottom Plate, Black Polystyrene, Cell Culture Treated, with lid, Sterile</td>
			<td style="width:137px;">Thermo Fisher Scientific</td>
			<td style="width:151px;">165305</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:268px;">SpectraMax M5 Multi-Mode Microplate</td>
			<td style="width:137px;">Molecular Devices</td>
			<td style="width:151px;"></td>
			<td></td>
		</tr>
	</tbody>
</table>

use of a caspase multiplexing assay to determine apoptosis in a hypothalamic cell model

La capacità di multiplexing saggi in studi sui meccanismi cellulari complesse elimina la necessità di esperimenti ripetitivi, fornisce controlli interni, e diminuisce rifiuti nei costi e reagenti. Qui si descrive l&#39;ottimizzazione di un saggio multiplex per valutare l&#39;apoptosi in seguito a un acido palmitico (PA) sfida in un modello ipotalamica in vitro, utilizzando sia fluorescenti e luminescenti saggi basati misurare conteggio delle cellule vitali e caspasi-3/7 attività in un ben 96 formato micropiastra. Seguendo PA sfida, cellule vitali sono stati determinati da un test di fluorescenza basato resazurin-. Caspasi-3/7 attività è stata poi determinata con un substrato luminogenic, DEVD e normalizzato al numero di cellulare. Questo saggio multiplexing è una tecnica utile per determinare cambiamento nell&#39;attività caspasi seguente uno stimolo apoptotico, come sfida acido grasso saturo. L&#39;acido grasso saturo PA può aumentare ipotalamica stress ossidativo e apoptosi, indicando la possibilità ImportaSNO di saggi come quello descritto qui in studio del rapporto tra acidi grassi saturi e funzione neuronale.

Il protocollo sopra descritto comporta multiplazione due test separati per determinare meccanismi della morte cellulare. Figura 1 mostra una panoramica del protocollo per determinare la vitalità cellulare e caspasi-3/7 attività. Attività di caspasi era significativamente aumentata in cellule stimolate con PA dopo 2 ore di incubazione (Figura 2A e Tabella 1). Perdita di integrità della membrana cellulare è un cambiamento morfologico associata con l&#39;induzione di ...

Watch this Scientific Journal Video about Use of a Caspase Multiplexing Assay to Determine Apoptosis in a Hypothalamic Cell Model at JoVE.com

Use of a Caspase Multiplexing Assay to Determine Apoptosis in a Hypothalamic Cell Model

Saggi Multiplex possono fornire informazioni utile per i meccanismi cellulari di base ed eliminare gli sprechi di reagenti ed esperimenti ripetitivi inutili. Descriviamo qui un multiplex caspasi-3/7 saggio di attività, utilizzando metodi fluorescenti e si basano luminescenti-, per determinare la vitalità cellulare in un modello in vitro ipotalamico seguente sfida ossidativa con acido palmitico.

L&#39;uso di una caspasi Multiplexing test per determinare apoptosi in un modello cellulare ipotalamica

The ability to multiplex assays in studies of complex cellular mechanisms eliminates the need for repetitive experiments, provides internal controls, and ...

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Neuroscience

14.9K Views.  Minneapolis Veterans Affairs Health Care System.  Saggi Multiplex possono fornire informazioni utile per i meccanismi cellulari di base ed eliminare gli sprechi di reagenti ed esperimenti ripetitivi inutili. Descriviamo qui un multiplex caspasi-3/7 saggio di attività, utilizzando metodi fluorescenti e si basano luminescenti-, per determinare la vitalità cellulare in un modello in vitro ipotalamico seguente sfida ossidativa con acido palmitico. 

Video: Use of a Caspase Multiplexing Assay to Determine Apoptosis in a Hypothalamic Cell Model

Optic Nerve Transection: A Model of Adult Neuron Apoptosis in the Central Nervous System

Retinal ganglion cells (RGCs) are CNS neurons that output visual information from the retina to the brain, via the optic nerve. 
The optic nerve can be accessed within the orbit of the eye and completely transected (axotomized), cutting the axons of the entire RGC population. Optic nerve 
transection is a reproducible model of apoptotic neuronal cell death in the adult CNS 1-4. This model is particularly attractive because the vitreous
 chamber of the eye acts as a capsule for drug delivery to the retina, permitting experimental manipulations via intraocular injections. The diffusion of chemicals 
through the vitreous fluid ensures that they act upon the entire RGC population. Moreover, RGCs can be selectively transfected by applying short interfering RNAs 
(siRNAs), plasmids, or viral vectors to the cut end of the optic nerve 5-7 or injecting vectors into their target, the superior colliculus 8. 
This allows researchers to study apoptotic mechanisms in the desired neuronal population without confounding effects on other bystander neurons or surrounding glia. 
An additional benefit is the ease and accuracy with which cell survival can be quantified after injury. The retina is a flat, layered tissue and RGCs are localized in 
the innermost layer, the ganglion cell layer. The survival of RGCs can be tracked over time by applying a fluorescent tracer (3% Fluorogold) to the cut end of the 
optic nerve at the time of axotomy, or by injecting the tracer into the superior colliculus (RGC target) one week prior to axotomy. The tracer is retrogradely transported, labeling 
the entire RGC population. Because the ganglion cell layer is a monolayer (one cell thick), RGC densities can be quantified in flat-mounted tissue, without the need 
for stereology. Optic nerve transection leads to the apoptotic death of 90% of injured RGCs within 14 days postaxotomy 9-11. RGC apoptosis has a 
characteristic time-course whereby cell death is delayed 3-4 days postaxotomy, after which the cells rapidly degenerate. This provides a time window for 
experimental manipulations directed against pathways involved in apoptosis.

Optic Nerve transection is a widely used model of adult CNS injury. Ninety percent of retinal ganglion cells (RGCs) whose axons are completely transected (axotomy) die within 14 days after axotomy. This model is easily amenable to experimental manipulations and highly reproducible.

Resezione del nervo ottico: un modello di apoptosi Neuron adulti nel Sistema Nervoso Centrale

Retinal ganglion cells (RGCs) are CNS neurons that output visual information from the retina to the brain, via the optic nerve. 
The optic nerve can be ...

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Neuroscienze

Neural-Colony Forming Cell Assay: An Assay To Discriminate Bona Fide Neural Stem Cells from Neural Progenitor Cells

The neurosphere assay (NSA) is one of the most frequently used methods to isolate, expand and also calculate the frequency of neural stem cells (NSCs). Furthermore, this serum-free culture system has also been employed to expand stem cells and determine their frequency from a variety of tumors and normal tissues. It has been shown recently that a one-to-one relationship does not exist between neurosphere formation and NSCs. This suggests that the NSA as currently applied, overestimates the frequency of NSCs in a mixed population of neural precursor cells isolated from both the embryonic and adult mammalian brain. This video practically demonstrates a novel collagen based semi- solid assay, the neural-colony forming cell assay (N-CFCA), which has the ability to discriminate stem from progenitor cells based on their long-term proliferative potential, and thus provides a method to enumerate NSC frequency. In the N-CFCA, colonies &ge;2 mm in diameter are derived from cells that meet all the functional criteria of a NSC, while colonies &lt; 2mm are derived from progenitors. The N-CFCA procedure can be used for cells prepared from different sources including primary and cultured adult or embryonic mouse CNS cells. Here we use cells prepared from passage one neurospheres generated from embryonic day 14 mice brain to perform N-CFCA. The cultures are replenished with proliferation medium every seven days for three weeks to allow the plated cells to exhibit their full proliferative potential and then the frequency of neural progenitor and bona fide neural stem cells is calculated respectively by counting the number of colonies that are &lt; 2mm and the ones that are &ge;2mm in reference to the number of cells that were initially plated.

This video protocol demonstrates how to discriminate and enumerate bona fide neural stem cells in a mixed population of neural precursor cells using the neural colony-forming cell assay.

Neural-formanti colonia saggio Cell: un test per discriminare Bona Fide cellule staminali neurali da cellule progenitrici neurali

The neurosphere assay (NSA) is one of the most frequently used methods to isolate, expand and also calculate the frequency of neural stem cells (NSCs). ...

Monitoring Cleaved Caspase-3 Activity and Apoptosis of Immortalized Oligodendroglial Cells using Live-cell Imaging and Cleaveable Fluorogenic-dye Substrates Following Potassium-induced Membrane Depolarization

The central nervous system can experience a number of stresses and neurological insults, which can have numerous adverse effects that ultimately lead to a reduction in neuronal population and function. Damaged axons can release excitatory molecules including potassium or glutamate into the extracellular matrix, which in turn, can produce further insult and injury to the supporting glial cells including astrocytes and oligodendrocytes 8, 16. If the insult persists, cells will undergo programmed cell death (apoptosis), which is regulated and activated by a number of well-established signal transduction cascades 14. Apoptosis and tissue necrosis can occur after traumatic brain injury, cerebral ischemia, and seizures. A classical example of apoptotic regulation is the family of cysteine-dependent aspartate-directed proteases, or caspases. Activated proteases including caspases have also been implicated in cell death in response to chronic neurodegenerative diseases including Alzheimer's, Huntington's, and Multiple Sclerosis 4, 14, 3, 11, 7.
In this protocol we describe the use of the NucView 488 caspase-3 substrate to measure the rate of caspase-3 mediated apoptosis in immortalized N19-oligodendrocyte (OLG) cell cultures 15, 5, following exposure to different extracellular stresses such as high concentrations of potassium or glutamate. The conditionally-immortalized N19-OLG cell line (representing the O2A progenitor) was obtained from Dr. Anthony Campagnoni (UCLA Semel Institute for Neuroscience) 15, 5, and has been previously used to study molecular mechanisms of myelin gene expression and signal transduction leading to OLG differentiation (e.g.6, 10). We have found this cell line to be robust with respect to transfection with exogenous myelin basic protein (MBP) constructs fused to either RFP or GFP (red or green fluorescent protein) 13, 12. Here, the N19-OLG cell cultures were treated with either 80 mM potassium chloride or 100 mM sodium glutamate to mimic axonal leakage into the extracellular matrix to induce apoptosis 9. We used a bi-functional caspase-3 substrate containing a DEVD (Asp-Glu-Val-Asp) caspase-3 recognition subunit and a DNA-binding dye 2. The substrate quickly enters the cytoplasm where it is cleaved by intracellular caspase-3. The dye, NucView 488 is released and enters the cell nucleus where it binds DNA and fluoresces green at 488 nm, signaling apoptosis. Use of the NucView 488 caspase-3 substrate allows for live-cell imaging in real-time 1, 10. In this video, we also describe the culturing and transfection of immortalized N19-OLG cells, as well as live-cell imaging techniques.

Monitoring Cleaved Caspase-3 Activity and Apoptosis of Immortalized Oligodendroglial Cells using Live-cell Imaging and Cleaveable Fluorogenic-dye Substrates Following Potassium-induced Membrane Depola

Live-cell imaging of caspase-3 mediated apoptosis in immortalized N19-oligodendrocyte cell cultures using the NucView 488 caspase-3 substrate. This technique is applicable for programmed cell death assays in real-time in a variety of cell types and tissues.

Monitoraggio spaccati Caspase-3 Attività e apoptosi di cellule oligodendrogliali Immortalata dal vivo utilizzando cellule Imaging e Cleaveable fluorogenici-dye seguenti supporti di potassio indotta depolarizzazione della membrana

The central nervous system can experience a number of stresses and neurological insults, which can have numerous adverse effects that ultimately lead to a ...

Functional Interrogation of Adult Hypothalamic Neurogenesis with Focal Radiological Inhibition

The functional characterization of adult-born neurons remains a significant challenge. Approaches to inhibit adult neurogenesis via invasive viral delivery or transgenic animals have potential confounds that make interpretation of results from these studies difficult. New radiological tools are emerging, however, that allow one to noninvasively investigate the function of select groups of adult-born neurons through accurate and precise anatomical targeting in small animals. Focal ionizing radiation inhibits the birth and differentiation of new neurons, and allows targeting of specific neural progenitor regions. In order to illuminate the potential functional role that adult hypothalamic neurogenesis plays in the regulation of physiological processes, we developed a noninvasive focal irradiation technique to selectively inhibit the birth of adult-born neurons in the hypothalamic median eminence. We describe a method for Computer tomography-guided focal irradiation (CFIR) delivery to enable precise and accurate anatomical targeting in small animals. CFIR uses three-dimensional volumetric image guidance for localization and targeting of the radiation dose, minimizes radiation exposure to nontargeted brain regions, and allows for conformal dose distribution with sharp beam boundaries. This protocol allows one to ask questions regarding the function of adult-born neurons, but also opens areas to questions in areas of radiobiology, tumor biology, and immunology. These radiological tools will facilitate the translation of discoveries at the bench to the bedside.

The function of adult-born mammalian neurons remains an active area of investigation. Ionizing radiation inhibits the birth of new neurons. Using computer tomography-guided focal irradiation (CFIR), three-dimensional anatomical targeting of specific neural progenitor populations can now be used to assess the functional role of adult neurogenesis.

Interrogatorio funzionale di età ipotalamico neurogenesi con focale Radiological inibizione

The functional characterization of adult-born neurons remains a significant challenge. Approaches to inhibit adult neurogenesis via invasive viral ...

A Novel Light Damage Paradigm for Use in Retinal Regeneration Studies in Adult Zebrafish

Light-induced retinal degeneration (LIRD) is commonly used in both rodents and zebrafish to damage rod and cone photoreceptors. In adult zebrafish, photoreceptor degeneration triggers M&#252;ller glial cells to re-enter the cell cycle and produce transient-amplifying progenitors. These progenitors continue to proliferate as they migrate to the damaged area, where they ultimately give rise to new photoreceptors. Currently, there are two widely-used LIRD paradigms, each of which results in varying degrees of photoreceptor loss and corresponding differences in the regeneration response. As more genetic and pharmacological tools are available to test the role of individual genes of interest during regeneration, there is a need to develop a robust LIRD paradigm. Here we describe a LIRD protocol that results in widespread and consistent loss of both rod and cone photoreceptors in which we have combined the use of two previously established LIRD techniques. Furthermore, this protocol can be extended for use in pigmented animals, which eliminates the need to maintain transgenic lines of interest on the albino background for LIRD studies.

Multiple light damage protocols have been described to damage photoreceptors and consequently induce a retinal regeneration response in adult zebrafish. This protocol describes an improved method that can be used in pigmented animals and that damages the vast majority of rod and cone photoreceptors across the entire retina.

A Novel Luce Danni Paradigma per l&#39;uso in retina Rigenerazione Studi in Zebrafish adulti

Light-induced retinal degeneration (LIRD) is commonly used in both rodents and zebrafish to damage rod and cone photoreceptors. In adult zebrafish, ...

Microglia as a Surrogate Biosensor to Determine Nanoparticle Neurotoxicity

Nanoparticles found in air pollutants can alter neurotransmitter profiles, increase neuroinflammation, and alter brain function. Therefore, the assay described here will aid in elucidating the role of microglia in neuroinflammation and neurodegenerative diseases. The use of microglia, resident immune cells of the brain, as a surrogate biosensor provides novel insight into how inflammatory responses mediate neuronal insults. Here, we utilize an immortalized murine microglial cell line, designated BV2, and describe a method for nanoparticle exposure using silver nanoparticles (AgNPs) as a standard. We describe how to expose microglia to nanoparticles, how to remove nanoparticles from supernatant, and how to use supernatant from activated microglia to determine toxicity, using hypothalamic cell survival as a measure. Following AgNP exposure, BV2 microglial activation was validated using a tumor necrosis factor alpha (TNF-&#945;) enzyme linked immunosorbent assay (ELISA). The supernatant was filtered to remove the AgNP and to allow cytokines and other secreted factors to remain in the conditioned media. Hypothalamic cells were then exposed to supernatant from AgNP activated microglia and survival of neurons was determined using a resazurin-based fluorescent assay. This technique is useful for utilizing microglia as a surrogate biomarker of neuroinflammation and determining the effect of neuroinflammation on other cell types.

Microglia (immune cells of the brain), are used as a surrogate biosensor to determine how nanoparticles influence neurotoxicity. We describe a series of experiments designed to assay microglial response to nanoparticles and exposure of hypothalamic neurons to supernatant from activated microglia to determine neurotoxicity.

Microglia come un biosensore surrogato per determinare nanoparticelle neurotossicità

Nanoparticles found in air pollutants can alter neurotransmitter profiles, increase neuroinflammation, and alter brain function. Therefore, the assay ...

The Use of Trace Eyeblink Classical Conditioning to Assess Hippocampal Dysfunction in a Rat Model of Fetal Alcohol Spectrum Disorders

Neonatal rats were administered a relatively high concentration of ethyl alcohol (11.9% v/v) during postnatal days 4-9, a time when the fetal brain undergoes rapid organizational change and is similar to accelerated brain changes that occur during the third trimester in humans. This model of fetal alcohol spectrum disorders (FASDs) produces severe brain damage, mimicking the amount and pattern of binge-drinking that occurs in some pregnant alcoholic mothers. We describe the use of trace eyeblink classical conditioning (ECC), a higher-order variant of associative learning, to assess long-term hippocampal dysfunction that is typically seen in alcohol-exposed adult offspring. At 90 days of age, rodents were surgically prepared with recording and stimulating electrodes, which measured electromyographic (EMG) blink activity from the left eyelid muscle and delivered mild shock posterior to the left eye, respectively. After a 5 day recovery period, they underwent 6 sessions of trace ECC to determine associative learning differences between alcohol-exposed and control rats. Trace ECC is one of many possible ECC procedures that can be easily modified using the same equipment and software, so that different neural systems can be assessed. ECC procedures in general, can be used as diagnostic tools for detecting neural pathology in different brain systems and different conditions that insult the brain.

Trace eyeblink classical conditioning (ECC) was used to assess hippocampal-dependent associative learning in adult rats that were administered a high concentration (11.9% v/v) of alcohol during early neonatal brain development. In general, ECC procedures are sound diagnostic tools for detecting brain dysfunction across many psychological and biomedical settings.

L'uso di traccia Eyeblink condizionamento classico per valutare la disfunzione Hippocampal in un modello del ratto dei disturbi dello spettro fetale alcol

Neonatal rats were administered a relatively high concentration of ethyl alcohol (11.9% v/v) during postnatal days 4-9, a time when the fetal brain ...

Live-cell Measurement of Odorant Receptor Activation Using a Real-time cAMP Assay

The enormous sizes of the mammalian odorant receptor (OR) families present difficulties to find their cognate ligands among numerous volatile chemicals. To efficiently and accurately deorphanize ORs, we combine the use of a heterologous cell line to express mammalian ORs and a genetically modified biosensor plasmid to measure cAMP production downstream of OR activation in real time. This assay can be used to screen odorants against ORs and vice versa. Positive odorant-receptor interactions from the screens can be subsequently confirmed by testing against various odor concentrations, generating concentration-response curves. Here we used this method to perform a high-throughput screening of an odorous compound against a human OR library expressed in Hana3A cells and confirmed that the positively-responding receptor is the cognate receptor for the compound of interest. We found this high-throughput detection method to be efficient and reliable in assessing OR activation and our data provide an example of its potential use in OR functional studies.

Characterizing the function of odorant receptors serves an indispensable part in the deorphanization process. We describe a method to measure the activation of odorant receptors in real time using a cAMP assay.

Vivere-cella misura di Odorant recettore attivazione mediante un'analisi di campo in tempo reale

The enormous sizes of the mammalian odorant receptor (OR) families present difficulties to find their cognate ligands among numerous volatile chemicals. ...

A Protocol for Measuring Cue Reactivity in a Rat Model of Cocaine Use Disorder

Cocaine use disorder (CUD) follows a trajectory of repetitive self-administration during which previously neutral stimuli gain incentive value. Cue reactivity, the sensitivity to cues previously linked with the drug-taking experience, plays a prominent role in human craving during abstinence. Cue reactivity can be assessed as the attentional orientation toward drug-associated cues that is measurable as appetitive approach behavior in both preclinical and human studies. Herein describes an assessment of cue reactivity in rats trained to self-administer cocaine. Cocaine self-administration is paired with the presentation of discrete cues that act as conditioned reinforcers (i.e., house light, stimulus light, infusion pump sounds). Following a period of abstinence, lever presses in the cocaine self-administration context accompanied by the discrete cues previously paired with cocaine infusion are measured as cue reactivity. This model is useful to explore neurobiological mechanisms underlying cue reactivity processes as well as to assess pharmacotherapies to suppress cue reactivity and therefore, modify relapse vulnerability. Advantages of the model include its translational relevance, and its face and predictive validities.&#160;The primary limitation of the model is that the cue reactivity task can only be performed infrequently and must only be used in short duration (e.g., 1 hour), otherwise rats will begin to extinguish the pairing of the discrete cues with the cocaine stimulus. The model is extendable to any positively reinforcing stimulus paired with discrete cues; though particularly applicable to drugs of abuse, this model may hold future applications in fields such as obesity, where palatable food rewards can act as positively reinforcing stimuli.

Cue reactivity is conceptualized as sensitivity to cues linked with drug-taking experiences that contribute to craving and relapse in abstinent humans. Cue reactivity is modeled in rats by measuring attentional orientation toward drug-associated cues that results in appetitive approach behavior in a cue reactivity test following self-administration and forced abstinence.

Un protocollo per la misurazione Cue reattività in un modello del ratto di disturbo da uso di cocaina

Cocaine use disorder (CUD) follows a trajectory of repetitive self-administration during which previously neutral stimuli gain incentive value. Cue ...

A Neurosphere Assay to Evaluate Endogenous Neural Stem Cell Activation in a Mouse Model of Minimal Spinal Cord Injury

Neural stem cells (NSCs) in the adult mammalian spinal cord are a relatively mitotically quiescent population of periventricular cells that can be studied in vitro using the neurosphere assay. This colony-forming assay is a powerful tool to study the response of NSCs to exogenous factors in a dish; however, this can also be used to study the effect of in vivo manipulations with the proper understanding of the strengths and limitations of the assay. One manipulation of the clinical interest is the effect of injury on endogenous NSC activation. Current models of spinal cord injury provide a challenge to study this as the severity of common contusion, compression, and transection models cause the destruction of the NSC niche at the site of the injury where the stem cells reside. Here, we describe a minimal injury model that causes localized damage at the superficial dorsolateral surface of the lower thoracic level (T7/8) of the adult mouse spinal cord. This injury model spares the central canal at the level of injury and permits analysis of the NSCs that reside at the level of the lesion at various time points following injury. Here, we show how the neurosphere assay can be utilized to study the activation of the two distinct, lineally-related, populations of NSCs that reside in the spinal cord periventricular region - primitive and definitive NSCs (pNSCs and dNSCs, respectively). We demonstrate how to isolate and culture these NSCs from the periventricular region at the level of injury and the white matter injury site. Our post-surgical spinal cord dissections show increased numbers of pNSC and dNSC-derived neurospheres from the periventricular region of injured cords compared to controls, speaking to their activation via injury. Furthermore, following injury, dNSC-derived neurospheres can be isolated from the injury site &#8212; demonstrating the ability of NSCs to migrate from their periventricular niche to sites of injury.

Here, we demonstrate the performance of a minimal spinal cord injury model in an adult mouse that spares the central canal niche housing endogenous neural stem cells (NSCs). We show how the neurosphere assay can be used to quantify activation and migration of definitive and primitive NSCs following injury.

Un saggio di Neurosphere per valutare l'attivazione delle cellule staminali neurali endogene in un modello murino di ferita del midollo spinale Minimal

Neural stem cells (NSCs) in the adult mammalian spinal cord are a relatively mitotically quiescent population of periventricular cells that can be studied ...