Name: kidney regeneration in adult zebrafish by gentamicin induced injury
Uploaded: 2015-08-03T14:30:00
Description: Watch this Scientific Journal Video about Kidney Regeneration in Adult Zebrafish by Gentamicin Induced Injury at JoVE.com

This work was supported by NIH grant F32DK091998 to CNK; NIH grant RO1DK041071 and Harvard Stem Cell Institute grant D001229 to IAD. The authors thank Neil Hukriede for the lhx1ain situ probe.

Declaração de Ética: NOTA: Todos os experimentos foram realizados de acordo com orientações Hospital Geral de Massachusetts para o uso de animais em pesquisa. 1. Preparação Prévia <ol><li> Determine quantas adulto zebrafish 6-12 meses de idade para ferir. Plano de ferir 10-20% mais peixes do que será necessário. A fim de minimizar a variabilidade, o uso combinado de peixe irmão idade criados em conjunto no mesmo tanque de modo que eles são aproximadamente do mesmo tamanho e tê...

<ol>
	<li>Humphreys, B. 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=Intrinsic+epithelial+cells+repair+the+kidney+after+injury.">Intrinsic epithelial cells repair the kidney after injury.</a> Cell Stem Cell. 2, 284-291 (2008).</li><li>Humphreys, B. 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=Repair+of+injured+proximal+tubule+does+not+involve+specialized+progenitors.">Repair of injured proximal tubule does not involve specialized progenitors.</a> Proc Natl Acad Sci U S A. 108, 9226-9231 (2011).</li><li>Guo, J. K., Cantley, L. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cellular+maintenance+and+repair+of+the+kidney.">Cellular maintenance and repair of the kidney.</a> Annu Rev Physiol. 72, 357-376 (2010).</li><li>Cirio, M. C., de Groh, E. D., de Caestecker, M. P., Davidson, A. J., Hukriede, N. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Kidney+regeneration:+common+themes+from+the+embryo+to+the+adult.">Kidney regeneration: common themes from the embryo to the adult.</a> Pediatr Nephrol. , (2013).</li><li>Little, M. H., Bertram, J. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Is+there+such+a+thing+as+a+renal+stem+cell.">Is there such a thing as a renal stem cell.</a> J Am Soc Nephrol. 20, 2112-2117 (2009).</li><li>Reimschuessel, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+fish+model+of+renal+regeneration+and+development.">A fish model of renal regeneration and development.</a> ILAR J. 42, 285-291 (2001).</li><li>Zhou, W., Boucher, R. C., Bollig, F., Englert, C., Hildebrandt, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+mesonephric+development+and+regeneration+using+transgenic+zebrafish.">Characterization of mesonephric development and regeneration using transgenic zebrafish.</a> Am J Physiol Renal Physiol. 299, F1040-F1047 (2010).</li><li>Poss, K. D., Wilson, L. G., Keating, M. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Heart+regeneration+in+zebrafish.">Heart regeneration in zebrafish.</a> Science. 298, 2188-2190 (2002).</li><li>Goessling, W., 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=APC+mutant+zebrafish+uncover+a+changing+temporal+requirement+for+wnt+signaling+in+liver+development.">APC mutant zebrafish uncover a changing temporal requirement for wnt signaling in liver development.</a> Dev Biol. 320, 161-174 (2008).</li><li>Pisharath, H., Rhee, J. M., Swanson, M. A., Leach, S. D., Parsons, M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Targeted+ablation+of+beta+cells+in+the+embryonic+zebrafish+pancreas+using+E.+coli+nitroreductase.">Targeted ablation of beta cells in the embryonic zebrafish pancreas using E. coli nitroreductase.</a> Mech Dev. 124, 218-229 (2007).</li><li>Swanhart, L. 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=Characterization+of+an+lhx1a+transgenic+reporter+in+zebrafish.">Characterization of an lhx1a transgenic reporter in zebrafish.</a> Int J Dev Biol. 54, 731-736 (2010).</li><li>Diep, C. Q., 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=Identification+of+adult+nephron+progenitors+capable+of+kidney+regeneration+in+zebrafish.">Identification of adult nephron progenitors capable of kidney regeneration in zebrafish.</a> Nature. 470, 95-100 (2011).</li><li>Lopez-Novoa, J. M., Quiros, Y., Vicente, L., Morales, A. I., Lopez-Hernandez, F. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=New+insights+into+the+mechanism+of+aminoglycoside+nephrotoxicity:+an+integrative+point+of+view.">New insights into the mechanism of aminoglycoside nephrotoxicity: an integrative point of view.</a> Kidney Int. 79, 33-45 (2011).</li><li>Hentschel, D. 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=Acute+renal+failure+in+zebrafish:+a+novel+system+to+study+a+complex+disease.">Acute renal failure in zebrafish: a novel system to study a complex disease.</a> Am J Physiol Renal Physiol. 288, F923-F929 (2005).</li><li>Gerlach, G. F., Schrader, L. N., Wingert, 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=Dissection+of+the+adult+zebrafish+kidney.">Dissection of the adult zebrafish kidney.</a> J Vis Exp. , (2011).</li><li>Fogazzi, G. B., Cameron, J. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Urinary+microscopy+from+the+seventeenth+century+to+the+present+day.">Urinary microscopy from the seventeenth century to the present day.</a> Kidney Int. 50, 1058-1068 (1996).</li><li>Nachtrab, G., Czerwinski, M., Poss, K. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sexually+dimorphic+fin+regeneration+in+zebrafish+controlled+by+androgen/GSK3+signaling.">Sexually dimorphic fin regeneration in zebrafish controlled by androgen/GSK3 signaling.</a> Curr Biol. 21, 1912-1917 (2011).</li><li>Zhou, W., Hildebrandt, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inducible+podocyte+injury+and+proteinuria+in+transgenic+zebrafish.">Inducible podocyte injury and proteinuria in transgenic zebrafish.</a> J Am Soc Nephrol. 23, 1039-1047 (2012).</li><li>Huang, 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+zebrafish+model+of+conditional+targeted+podocyte+ablation+and+regeneration.">A zebrafish model of conditional targeted podocyte ablation and regeneration.</a> Kidney Int. 83, 1193-1200 (2013).</li></ol>

O peixe-zebra é ideal para estudar a regeneração de órgãos adultos, incluindo o rim adulto mesonephric 6. Estudos recentes têm se aproveitado de marcadores moleculares e novas linhas repórter transgénico para melhor caracterizar as etapas que ocorrem durante a regeneração de néfrons e quais as células podem ser responsáveis ​​7,12. Observação de cilindros urinários foi usado para mais de um século, para diagnosticar a doença renal em seres humanos 16. Aqui usamos a ...

O rim é essencial para a homeostase dos fluidos, regulação da pressão arterial e filtragem de resíduos do corpo. Embora os mamíferos são capazes de reparar néfrons existentes após a lesão usando células epiteliais diferenciadas 1-4, eles parecem não ter um pool de células-tronco reservadas 5 e são incapazes de formar novos néfrons de novo. Em contraste com os mamíferos, peixes adultos são capazes de formar novas nefrónios ao longo da vida adulta para apoiar o crescimento dos peixes e, em resposta a uma lesão 6,7. O peixe-zebra, Danio rerio, é um organismo modelo de valor inestimável para o estudo da regeneração de órgãos 10/08 e tem o potencial de fornecer insights poderosos em aplicações de engenharia a reparação de rins humanos. A Tg (Lhx1a: EGFP) transgene 11 foi mostrado para identificar um conjunto de células progenitoras no nefrónio do rim adulto zebrafish 12, no entanto, os mecanismos que controlam a resposta de células lhx1a + para r lesãoemain claro. A gentamicina é um antibiótico aminoglicosídeo amplamente utilizado com efeitos nefrotóxicos e ototóxicos conhecidos em humanos 13. Injeção intra-peritoneal de gentamicina é um método estabelecido de induzir lesão renal aguda em peixes 6. Esta lesão em peixes imita a perda de epitélio tubular e cicatrizes de glomérulos que ocorre em seres humanos após overdose de gentamicina 14. Indução de lesão no peixe-zebra por injecção de gentamicina é uma maneira conveniente de induzir uma resposta forte de regeneração, síncrona, com muitas novas nefrónios produzidos e procedendo em simultâneo através de estágios de formação, diferenciação e proliferação. Este protocolo detalhes o nosso método de lesão robusta e reproduzível no peixe-zebra rim adulto, utilizando um processo de triagem visual não invasivo para minimizar valores atípicos. Nós tirar proveito do facto de que a lesão com gentamicina leva à morte do tecido renal epitelial e formatoion de moldes tubulares renais, que depois se acumulam em massas nas condutas mesonéfricos e cloaca. Estes são passados ​​pelos peixes e pode ser observada visualmente na água. Isto permite-nos para triagem de peixe com forte lesão não-letal, que pode então ser combinadas para fazer novas experiências. Minimizando o número de peixes ou peixe ileso que morrem antes de chegar ao ponto final do experimento leva a mais uniforme e eficiente de coleta de dados e análise. Além disso, não são necessários dispositivos especiais ou reagentes, tornando este método custo-efetivo e adequado para uso em um ambiente acadêmico ou de ensino. Utilizando o nosso método, aqui mostram os efeitos de doses crescentes de gentamicina sobre a regeneração do rim, assim como o efeito do aumento da temperatura.

<table border="0" cellpadding="0" cellspacing="0" width="726">
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Name of Material/ Equipment</td>
			<td style="width:101px;">Company</td>
			<td style="width:119px;">Catalog Number</td>
			<td style="width:291px;">Comments/Description</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">gentamicin sodium sulfate</td>
			<td style="width:101px;">Sigma</td>
			<td style="width:119px;">G1264</td>
			<td>TOXIC, purity varies from batch to batch</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">plastic transfer pipets</td>
			<td style="width:101px;">Fisher</td>
			<td style="width:119px;">13-711-7M</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">1 ml Norm-Ject syringes</td>
			<td style="width:101px;">Electron Microscopy Sciences</td>
			<td align="right" style="width:119px;">72520</td>
			<td>green plastic syringes, ordinary 1ml syringes are OK, but harder to read accurately</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">30G1/2 needles</td>
			<td style="width:101px;">Becton Dickinson</td>
			<td align="right" style="width:119px;">305106</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">ethyl 3-aminobenzoaate methanesulfonate salt (tricaine)</td>
			<td style="width:101px;">Sigma</td>
			<td style="width:119px;">A5040</td>
			<td>IRRITANT</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">16% paraformaldehyde</td>
			<td style="width:101px;">Electron Microscopy Sciences</td>
			<td align="right" style="width:119px;">15710</td>
			<td>Make 4% in 1xPBS for working solution</td>
		</tr>
	</tbody>
</table>

kidney regeneration in adult zebrafish by gentamicin induced injury

The kidney is essential for fluid homeostasis, blood pressure regulation and filtration of waste from the body. The fundamental unit of kidney function is the nephron. Mammals are able to repair existing nephrons after injury, but lose the ability to form new nephrons soon after birth. In contrast to mammals, adult fish produce new nephrons (neonephrogenesis) throughout their lives in response to growth requirements or injury. Recently, lhx1a has been shown to mark nephron progenitor cells in the adult zebrafish kidney, however mechanisms controlling the formation of new nephrons after injury remain unknown. Here we show our method for robust and reproducible injury in the adult zebrafish kidney by intraperitoneal (i.p.) injection of gentamicin, which uses a noninvasive visual screening process to select for fish with strong but nonlethal injury. Using this method, we can determine optimal gentamicin dosages for injury and go on to demonstrate the effect of higher temperatures on kidney regeneration in zebrafish.

Lesão de gentamicina pode ser confirmado visualmente pela observação de moldes epiteliais renais em água (Figura 1). Diferentes doses de gentamicina foram usadas para ferir adulto zebrafish wildtype TuAB, resultando em um número crescente de lhx1a + agregados celulares no rim regeneração (Figura 1A - D). Gesso branco pode ser facilmente visto na água um dia após a lesão (Figura 1E - H). Uma baixa dose de gentamicina r...

Watch this Scientific Journal Video about Kidney Regeneration in Adult Zebrafish by Gentamicin Induced Injury at JoVE.com

Kidney Regeneration in Adult Zebrafish by Gentamicin Induced Injury

Here we present a reliable method to study adult kidney regeneration by inducing acute kidney injury by gentamicin injection. We show that injury is dependent on gentamicin dosage and environmental temperature using in situ hybridization to label lhx1a+ developing new nephrons.

A regeneração renal em Zebrafish Adulto por lesão induzida pela gentamicina

The kidney is essential for fluid homeostasis, blood pressure regulation and filtration of waste from the body. The fundamental unit of kidney function is ...

kidney-regeneration-in-adult-zebrafish-by-gentamicin-induced-injury

Research

JoVE Journal

Developmental Biology

Mechanical Vessel Injury in Zebrafish Embryos

Zebrafish (Danio rerio) embryos have proven to be a powerful model for studying a variety of developmental and disease processes. External development and optical transparency make these embryos especially amenable to microscopy, and numerous transgenic lines that label specific cell types with fluorescent proteins are available, making the zebrafish embryo an ideal system for visualizing the interaction of vascular, hematopoietic, and other cell types during injury and repair in vivo. Forward and reverse genetics in zebrafish are well developed, and pharmacological manipulation is possible. We describe a mechanical vascular injury model using micromanipulation techniques that exploits several of these features to study responses to vascular injury including hemostasis and blood vessel repair. Using a combination of video and timelapse microscopy, we demonstrate that this method of vascular injury results in measurable and reproducible responses during hemostasis and wound repair. This method provides a system for studying vascular injury and repair in detail in a whole animal model.

This article describes a method for creating a mechanical vessel injury in zebrafish embryos. This injury model provides a platform for studying hemostasis, injury-related inflammation, and wound healing in an organism ideally suited for real-time microscopy.

Lesão Vessel Mecânica em embriões Zebrafish

Zebrafish (Danio rerio) embryos have proven to be a powerful model for studying a variety of developmental and disease processes.  External development ...

Biologia do Desenvolvimento

Hepatocyte-specific Ablation in Zebrafish to Study Biliary-driven Liver Regeneration

The liver has a great capacity to regenerate. Hepatocytes, the parenchymal cells of the liver, can regenerate in one of two ways: hepatocyte- or biliary-driven liver regeneration. In hepatocyte-driven liver regeneration, regenerating hepatocytes are derived from preexisting hepatocytes, whereas, in biliary-driven regeneration, regenerating hepatocytes are derived from biliary epithelial cells (BECs). For hepatocyte-driven liver regeneration, there are excellent rodent models that have significantly contributed to the current understanding of liver regeneration. However, no such rodent model exists for biliary-driven liver regeneration. We recently reported on a zebrafish liver injury model in which BECs extensively give rise to hepatocytes upon severe hepatocyte loss. In this model, hepatocytes are specifically ablated by a pharmacogenetic means. Here we present in detail the methods to ablate hepatocytes and to analyze the BEC-driven liver regeneration process. This hepatocyte-specific ablation model can be further used to discover the underlying molecular and cellular mechanisms of biliary-driven liver regeneration. Moreover, these methods can be applied to chemical screens to identify small molecules that augment or suppress liver regeneration.

To help assess the molecular mechanisms underlying zebrafish biliary-driven liver regeneration, we established a liver injury model in which the nitroreductase-expressing hepatocytes are genetically ablated upon metronidazole treatment. In this protocol, we describe how to adeptly manipulate, monitor and analyze hepatocyte ablation and biliary-driven liver regeneration.

Ablação específicas do hepatócito em Zebrafish para estudar a regeneração do fígado-driven biliar

The liver has a great capacity to regenerate. Hepatocytes, the parenchymal cells of the liver, can regenerate in one of two ways: hepatocyte- or ...

Development of an Ethanol-induced Fibrotic Liver Model in Zebrafish to Study Progenitor Cell-mediated Hepatocyte Regeneration

Sustained liver fibrosis with continuation of extracellular matrix (ECM) protein build-up results in the loss of cellular competency of the liver, leading to cirrhosis with hepatocellular dysfunction. Among multiple hepatic insults, alcohol abuse can lead to significant health problems including liver failure and hepatocellular carcinoma. Nonetheless, the identity of endogenous cellular sources that regenerate hepatocytes in response to alcohol has not been properly investigated. Moreover, few studies have effectively modeled hepatocyte regeneration upon alcohol-induced injury. We recently reported on establishing an ethanol (EtOH)-induced fibrotic liver model in zebrafish in which hepatic progenitor cells (HPCs) gave rise to hepatocytes upon near-complete hepatocyte loss in the presence of fibrogenic stimulus. Furthermore, through chemical screens using this model, we identified multiple small molecules that enhance hepatocyte regeneration. Here we describe in detail the procedures to develop an EtOH-induced fibrotic liver model and to perform chemical screens using this model in zebrafish. This protocol will be a critical tool to delineate the molecular and cellular mechanisms of how hepatocyte regenerates in the fibrotic liver. Furthermore, these methods will facilitate potential discovery of novel therapeutic strategies for chronic liver disease in vivo.

Sustained fibrosis with deposition of excessive extracellular matrix proteins leads to cirrhosis. Alcohol abuse is one of the main causes of severe liver disease. We established an ethanol-induced zebrafish fibrotic liver model to study the mechanisms and strategies of promoting hepatocyte regeneration upon alcohol-induced injury.

Desenvolvimento de um modelo de fígado fibrótica induzida por etanol no peixe-zebra para estudar Progenitor mediada por células de regeneração de hepatócitos

Sustained liver fibrosis with continuation of extracellular matrix (ECM) protein build-up results in the loss of cellular competency of the liver, leading ...

Culture of Adult Transgenic Zebrafish Retinal Explants for Live-cell Imaging by Multiphoton Microscopy

An endogenous regeneration program is initiated by M&#252;ller glia in the adult zebrafish (Danio rerio) retina following neuronal damage and death. The M&#252;ller glia re-enter the cell cycle and produce neuronal progenitor cells that undergo subsequent rounds of cell divisions and differentiate into the lost neuronal cell types. Both M&#252;ller glia and neuronal progenitor cell nuclei replicate their DNA and undergo mitosis in distinct locations of the retina, i.e. they migrate between the basal Inner Nuclear Layer (INL) and the Outer Nuclear Layer (ONL), respectively, in a process described as Interkinetic Nuclear Migration (INM). INM has predominantly been studied in the developing retina. To examine the dynamics of INM in the adult regenerating zebrafish retina in detail, live-cell imaging of fluorescently-labeled M&#252;ller glia/neuronal progenitor cells is required. Here, we provide the conditions to isolate and culture dorsal retinas from Tg[gfap:nGFP]mi2004 zebrafish that were exposed to constant intense light for 35 h. We also show that these retinal cultures are viable to perform live-cell imaging experiments, continuously acquiring z-stack images throughout the thickness of the retinal explant for up to 8 h using multiphoton microscopy to monitor the migratory behavior of gfap:nGFP-positive cells. In addition, we describe the details to perform post-imaging analysis to determine the velocity of apical and basal INM. To summarize, we established conditions to study the dynamics of INM in an adult model of neuronal regeneration. This will advance our understanding of this crucial cellular process and allow us to determine the mechanisms that control INM.

Zebrafish retinal regeneration has mostly been studied using fixed retinas. However, dynamic processes such as interkinetic nuclear migration occur during the regenerative response and require live-cell imaging to investigate the underlying mechanisms. Here, we describe culture and imaging conditions to monitor Interkinetic Nuclear Migration (INM) in real-time using multiphoton microscopy.

Cultura do Adulto Transgênicos Zebrafish Retinal explantes for Imaging Em células vivas, por Multiphoton Microscopia

An endogenous regeneration program is initiated by M&#252;ller glia in the adult zebrafish (Danio rerio) retina following neuronal damage and death. The ...

Precise Cellular Ablation Approach for Modeling Acute Kidney Injury in Developing Zebrafish

Acute Kidney Injury (AKI) is a common medical condition with a high mortality rate. With the repair abilities of the kidney, it is possible to restore adequate kidney function after supportive treatment. However, a better understanding of how nephron cell death and repair occur on the cellular level is required to minimize cell death and to enhance the regenerative process. The zebrafish pronephros is a good model system to accomplish this goal because it contains anatomical segments that are similar to the mammalian nephron. Previously, the most common model used to study kidney injury in fish was the pharmacological gentamicin model. However, this model does not allow for precise spatiotemporal control of injury, and hence it is difficult to study cellular and molecular processes involved in kidney repair. To overcome this limitation, this work presents a method through which, in contrast to the gentamicin approach, a specific Green Fuorescent Protein (GFP)-expressing nephron segment can be photoablated using a violet laser light (405 nm). This novel model of AKI provides many advantages that other methods of epithelial injury lack. Its main advantages are the ability to &#34;dial&#34; the level of injury and the precise spatiotemporal control in the robust in vivo animal model. This new method has the potential to significantly advance the level of understanding of kidney injury and repair mechanisms.

This work presents a new in vivo model of segmental kidney injury using kidney GFP transgenic zebrafish. The model allows for the induction of the targeted ablation of kidney epithelial cells to show the cellular mechanisms of nephron injury and repair.

Abordagem precisa de ablação celular para modelagem de lesão renal aguda no desenvolvimento de peixe-zebra

Acute Kidney Injury (AKI) is a common medical condition with a high mortality rate. With the repair abilities of the kidney, it is possible to restore ...

Histological Analyses of Acute Alcoholic Liver Injury in Zebrafish

Alcoholic Liver Disease (ALD) refers to damage to the liver due to acute or chronic alcohol abuse. It is among the leading causes of alcohol-related morbidity and mortality and affects more than 2 million people in the United States. A better understanding of the cellular and molecular mechanisms underlying alcohol-induced liver injury is crucial for developing effective treatment for ALD. Zebrafish larvae exhibit hepatic steatosis and fibrogenesis after just 24 h of exposure to 2% ethanol, making them useful for the study of acute alcoholic liver injury. This work describes the procedure for acute ethanol treatment in zebrafish larvae and shows that it causes steatosis and swelling of the hepatic blood vessels. A detailed protocol for Hematoxylin and Eosin (H&#38;E) staining that is optimized for the histological analysis of the zebrafish larval liver, is also described. H&#38;E staining has several unique advantages over immunofluorescence, as it marks all liver cells and extracellular components simultaneously and can readily detect hepatic injury, such as steatosis and fibrosis. Given the increasing usage of zebrafish in modeling toxin and virus-induced liver injury, as well as inherited liver diseases, this protocol serves as a reference for the histological analyses performed in all these studies.

This protocol describes histological analyses of the livers from zebrafish larvae that have been treated with 2% ethanol for 24 h. Such acute ethanol treatment results in hepatic steatosis and swelling of the hepatic vasculature.

Análises histológicas de lesão hepática alcoólica aguda em peixe-zebra

Alcoholic Liver Disease (ALD) refers to damage to the liver due to acute or chronic alcohol abuse. It is among the leading causes of alcohol-related ...

A Simplified and Efficient Method to Isolate Primary Human Keratinocytes from Adult Skin Tissue

Primary human keratinocytes isolated from fresh skin tissues and their expansion in vitro have been widely used for laboratory research and for clinical applications. The conventional isolation method of human keratinocytes involves a two-step sequential enzymatic digestion procedure, which has been proven to be inefficient in generating primary cells from adult tissues due to the low cell recovery rate and reduced cell viability. We recently reported an advanced method to isolate human primary epidermal progenitor cells from skin tissues that utilizes the Rho kinase inhibitor Y-27632 in the medium. Compared with the traditional protocol, this new method is simpler, easier, and less time-consuming, and increases epithelial stem cell yield and enhances their stem cell characteristics. Moreover, the new methodology does not require the separation of the epidermis from the dermis, and, therefore, is suitable for isolating cells from different types of adult tissues. This new isolation method overcomes the major shortcomings of conventional methods and is more suitable for producing large numbers of epidermal cells with high potency both for laboratory and for clinical applications. Here, we describe the new method in detail.

Here we present a protocol to efficiently isolate primary human keratinocytes from adult skin tissues. This method simplifies the conventional procedure by using the ROCK Inhibitor Y-27632 in the inoculation medium to spontaneously separate epidermal cells from dermal cells.

Um método simplificado e eficiente para isolar os queratinócitos humanos primários do tecido da pele de adultos

Primary human keratinocytes isolated from fresh skin tissues and their expansion in vitro have been widely used for laboratory research and for clinical ...

Nanoparticle-mediated siRNA Gene-silencing in Adult Zebrafish Heart

Mammals have a very limited capacity to regenerate the heart after myocardial infarction. On the other hand, the adult zebrafish regenerates its heart after apex resection or cryoinjury, making it an important model organism for heart regeneration study. However, the lack of loss-of-function methods for adult organs has restricted insights into the mechanisms underlying heart regeneration. RNA interference via different delivery systems is a powerful tool for silencing genes in mammalian cells and model organisms. We have previously reported that siRNA-encapsulated nanoparticles successfully enter cells and result in a remarkable gene-specific knockdown in the regenerating adult zebrafish heart. Here, we present a simple, rapid, and efficient protocol for the dendrimer-mediated siRNA delivery and gene-silencing in the regenerating adult zebrafish heart. This method provides an alternative approach for determining gene functions in adult organs in zebrafish and can be extended to other model organisms as well.

It remains a major challenge to develop conditional gene-knockout or effective gene-knockdown in adult zebrafish organs. Here we report a protocol for performing nanoparticle-mediated siRNA gene-silencing in adult zebrafish heart, thus providing a new loss-of-function method for studying adult organs in zebrafish and other model organisms.

SiRNA Nanoparticle-mediada-silenciamento no coração de Zebrafish adulto

Mammals have a very limited capacity to regenerate the heart after myocardial infarction. On the other hand, the adult zebrafish regenerates its heart ...

Adult Zebrafish Injury Models to Study the Effects of Prednisolone in Regenerating Bone Tissue

Zebrafish are able to regenerate various organs, including appendages (fins) after amputation. This involves the regeneration of bone, which regrows within roughly two weeks after injury. Furthermore, zebrafish are able to heal bone rapidly after trepanation of the skull, and repair fractures that can be easily introduced into zebrafish bony fin rays. These injury assays represent feasible experimental paradigms to test the effect of administered drugs on rapidly forming bone. Here, we describe the use of these 3 injury models and their combined use with systemic glucocorticoid treatment, which exerts bone inhibitory and immunosuppressive effects. We provide a workflow on how to prepare for immunosuppressive treatment in adult zebrafish, illustrate how to perform fin amputation, trepanation of calvarial bones, and fin fractures, and describe how the use of glucocorticoids affects both bone forming osteoblasts and cells of the monocyte/macrophage lineage as part of innate immunity in bone tissue.

Here, we describe 3 adult zebrafish injury models and their combined use with immunosuppressive drug treatment. We provide guidance on imaging of regenerating tissues and on detecting bone mineralization therein.

Modelos de lesão adulto Zebrafish para estudar os efeitos de prednisolona na regeneração de tecido ósseo

Zebrafish are able to regenerate various organs, including appendages (fins) after amputation. This involves the regeneration of bone, which regrows ...

Electroporation Method for In Vivo Delivery of Plasmid DNA in the Adult Zebrafish Telencephalon

Electroporation is a transfection method in which an electrical field is applied to cells to create temporary pores in a cell membrane and increase its permeability, thereby allowing different molecules to be introduced to the cell. In this paper, electroporation is used to introduce plasmids to ependymoglial cells, which line the ventricular zone of the adult zebrafish telencephalon. A fraction of these cells shows stem cell properties and generates new neurons in the zebrafish brain; therefore, studying their behavior is essential to determine their roles in neurogenesis and regeneration. The introduction of plasmids via electroporation enables long-term labeling and tracking of a single ependymoglial cell. Furthermore, plasmids such as Cre recombinase or Cas9 can be delivered to single ependymoglial cells, which enables gene recombination or gene editing and provides a unique opportunity to assess the cell&#8217;s autonomous gene function in a controlled, natural environment. Finally, this detailed, step-by-step electroporation protocol is used to obtain successful introduction of plasmids into a large number of single ependymoglial cells.

Presented here is an electroporation method for plasmid DNA delivery and ependymoglial cell labeling in the adult zebrafish telencephalon. This protocol is a quick and efficient method to visualize and trace individual ependymoglial cells and opens up new possibilities to apply electroporation to a broad range of genetic manipulations.

Método de Electroporation para in vivo entrega de DNA plasmídeo no adulto zebrafish Telencephalon

Electroporation is a transfection method in which an electrical field is applied to cells to create temporary pores in a cell membrane and increase its ...