我们感谢鲍勃·诺瓦克（安道尔的技术）的技术帮助和建议。 SA-S。的德意志研究联合会（DFG）的海森堡奖学金的支持。这项工作是支持，DFG授予SE2016/7-1。

1。单细胞进行标记注入单细胞阶段的胚胎的质粒编码GFP或任何GFP融合蛋白的β-肌动蛋白启动子的控制下。在开发过程中，GFP的表达，在时尚的马赛克。这里，我们使用的转基因构建体的Tg []，放置的α-辅肌动蛋白-GFP融合蛋白的β-肌动蛋白启动子的控制下的β-肌动蛋白：α-辅肌动蛋白-GFP。 2。胚胎嵌入<ol class="lalpha"><li>收藏报错斑马鱼胚胎中，并保持在正常条件下，直到28高倍视野（分段根据12）。 </li><li> Dechorionate胚胎体视显微镜下，用镊子（杜蒙＃5）。 </li><li>准备在显微镜载片用凡士林环。 </li><li>准备1％低熔点琼脂糖/在10毫升10％的三卡因溶液与E3介质：煮沸100毫克琼脂糖E3溶液，得到的液体和均匀的琼脂糖溶液;等分和存储未使用的琼脂糖溶液，在-20℃下以供进一步使用。立即使用，让煮熟的解决方案冷静下来，保持在最大。 39°C。添加三卡因库存中的溶液中，得到的最终浓度为10％的三卡因。三卡因和琼脂糖均是必要的，以防止胚胎的变动。 </li><li>嵌入单个胚胎在1％低熔点琼脂糖/ 10％三卡因/ E3介质凡士林环内，与胚胎铺设自然的一侧，轻轻用盖玻片覆盖，只是为了保持胚胎到位并避免凸这将打破光的表面。理想的情况下，将有针对性的胚胎肌肉组织的触摸盖玻片。 </li></ol> 3。胚胎激光伤人<ol class="lalpha"><li>准备微点激光和显微镜： <ol class="lroman"><li>如何设置和使用的激光显微镜结合的详细说明，请参阅微点激光手册。 </li><li>选择正确的染料的435纳米波长的激光束的产生。 </li><li>调整激光功率，通过使用衰减滑块。激光功率足够强大，打破了玻璃表面的单脉冲（ 例如对焦的样本，以测试此盖玻片）。这是细胞消融所需的激光功率。 </li></ol></li><li>专注于感兴趣的使用安装在显微镜的目镜的分划板的区域或小区。使用20倍的物镜（40倍，将允许更精确的损害，但往往此透镜的工作距离是不够的）。 </li></ol> 注1：激光不仅会损伤细胞的聚焦平面内，而且细胞的上方和下方激光束内。确保激光最佳地设定和调整内的z-轴的最大焦点的实验之前。最好是确定的激光损伤的深度进行实验之前，为了知道哪个小区极可能会受伤。 <ol class="lalpha" start="3"><li>设置的可视化的实验所需要的光：明场正常使用，或荧光如果目标是荧光标记的细胞。 </li><li>寄脉冲的激光的目标区域，或多个脉冲，这取决于所期望的程度的损伤。 </li></ol> 4。伤人及恢复分析<ol class="lalpha"><li>如果需要，该程序可以被记录的激光损伤活（ 例如，使用Metamorph软件流采集选项）。 </li><li>伤人后，立即被删除的胚胎从琼脂糖轻轻用钳子放回蛋水的恢复。 </li></ol> 注2：肌肉活动（游泳和抽搐）是特别重要的是骨骼肌肉的恢复。由于胚胎不能移动，因为三卡因曝光和僵硬琼脂糖嵌入，它不是recommended，以维持胚胎幻灯片和盖玻片之间的时间过长。 <ol class="lalpha" start="3"><li>恢复后，可以固定的，胚胎，分析所需的通过光，荧光或共聚焦显微镜。 </li></ol>

<ol>
	<li>Charge, S. B., Rudnicki, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cellular+and+molecular+regulation+of+muscle+regeneration.">Cellular and molecular regulation of muscle regeneration.</a> Physiol. Rev. 84, 209-238 (2004).</li><li>Steffen, L. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+zebrafish+runzel+muscular+dystrophy+is+linked+to+the+titin+gene.">The zebrafish runzel muscular dystrophy is linked to the titin gene.</a> Dev. Biol. 309, 180-192 (2007).</li><li>Bassett, D., Currie, P. D. <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+a+zebrafish+model+of+muscular+dystrophy.">Identification of a zebrafish model of muscular dystrophy.</a> Clin. Exp. Pharmacol. Physiol. 31, 537-540 (2004).</li><li>Kawahara, G., Serafini, P. R., Myers, J. A., Alexander, M. S., Kunkel, L. M. <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+zebrafish+dysferlin+by+morpholino+knockdown.">Characterization of zebrafish dysferlin by morpholino knockdown.</a> Biochem. Biophys. Res. Commun. 413, 358-363 (2011).</li><li>Behra, M., Etard, C., Cousin, X., Str&#228;hle, U. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+use+of+zebrafish+mutants+to+identify+secondary+target+effects+of+acetylcholine+esterase+inhibitors.">The use of zebrafish mutants to identify secondary target effects of acetylcholine esterase inhibitors.</a> Toxicol. Sci. 77, 325-333 (2004).</li><li>Otten, 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=Xirp+proteins+mark+injured+skeletal+muscle+in+zebrafish.">Xirp proteins mark injured skeletal muscle in zebrafish.</a> PLoS One. 7, e31041 (2012).</li><li>Roostalu, U., Str&#228;hle, U. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vivo+imaging+of+molecular+interactions+at+damaged+sarcolemma.">In vivo imaging of molecular interactions at damaged sarcolemma.</a> Dev. Cell. 22, 515-529 (2012).</li><li>Stickney, H. L., Barresi, M. J., Devoto, S. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Somite+development+in+zebrafish.">Somite development in zebrafish.</a> Dev. Dyn. 219, 287-303 (2000).</li><li>Stellabotte, F., Dobbs-McAuliffe, B., Fernandez, D. A., Feng, X., Devoto, S. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dynamic+somite+cell+rearrangements+lead+to+distinct+waves+of+myotome+growth.">Dynamic somite cell rearrangements lead to distinct waves of myotome growth.</a> Development. 134, 1253-1257 (2007).</li><li>Choi, W. Y., 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=Cardiac+regeneration.">Cardiac regeneration.</a> Curr. Top. Dev. Biol. 100, 319-344 (2012).</li><li>Stewart, S., Stankunas, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Limited+dedifferentiation+provides+replacement+tissue+during+zebrafish+fin+regeneration.">Limited dedifferentiation provides replacement tissue during zebrafish fin regeneration.</a> Dev. Biol. 365, 339-349 (2012).</li><li>Kimmel, C. B., Ballard, W. W., Kimmel, S. R., Ullmann, B., Schilling, T. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stages+of+embryonic+development+of+the+zebrafish.">Stages of embryonic development of the zebrafish.</a> Dev. Dyn. , 203-253 (1995).</li></ol>

没有利益冲突的声明。

激光介导的损伤是造成所需大小的伤口，切除细胞，以研究在受控条件下的斑马鱼胚胎再生一个功能强大的方法。值得注意的是，细胞可以有针对性的精确（ 图2），可以控制损伤区以及定时。随后，上述损伤部位和再生过程很容易监测，记录（ 图3），并进行分析（ 图1）。然而，虽然激光以及集中在x-和y-轴，它不能完全集中在z-轴。这可能会导致损坏位于?...

<table border="1"><tbody><tr><td>加热块</td><td></td><td></td><td></td></tr><tr><td>对＃5镊子</td><td>杜蒙</td><td></td><td></td></tr><tr><td>载玻片</td><td>门泽尔</td><td></td><td> 76 x 26毫米</td></tr><tr><td>盖玻片</td><td>罗斯</td><td></td><td> 50×24毫米＃1 </td></tr><tr><td>凡士林</td><td></td><td></td><td></td></tr><tr><td>体视显微镜</td><td>徕卡</td><td></td><td> MZFLIII </td></tr><tr><td>微点激光</td><td>安道​​尔技术</td><td></td><td></td></tr><tr><td>荧光显微镜</td><td>蔡司</td><td></td><td> Axioplan II </td></tr><tr><td> Metamorph软件</td><td>分子器件</td><td></td><td></td></tr><tr><td></td><td></td><td></td><td> 试剂 <ul><li>低熔点琼脂糖（＃50081，龙沙） </li><li>三卡因储备溶液：400毫克三卡因（＃A-5040，Sigma-Aldrich公司）/ 100毫升蒸馏水2 O pH值9.0 </li><li> E3介质（5 mM氯化钠，0.17 mM KCl中，0.33毫的CaCl 2，0.33毫用MgSO 4） </li></ul></td></tr></tbody></table>

laser-inflicted injury of zebrafish embryonic skeletal muscle

不同的实验方法，使用鼠标的目的是研究肌肉再生，的包括myotoxin注射（布比卡因，心脏毒素或notexin），，，肌肉移植（神经损伤周围血管离断术诱导再生），大强度运动引起肌肉损伤，但也小鼠的肌营养不良症模型如评论这些方法mdx小鼠（参见图1）。在斑马鱼基因的方法包括突变体，表现出肌营养不良症的表型（，如runzel 2或sapje 3）和反义寡核苷酸吗啉代，阻止营养不良相关基因的表达。此外，化学方法，也有可能， 例如 ，加兰他敏，一种化学化合物抑制乙酰胆碱酯酶，从而导致hypercontraction，最终导致肌营养不良症5。然而，遗传学和药理学方法克enerally影响个人所有的肌肉内，而身体造成伤害的程度，更容易控制时间和空间上1。本地化的人身伤害可以作为内部控制的评估对侧肌肉。事实上，我们最近用激光消融介导的细胞研究在斑马鱼胚胎6骨骼肌再生，而另一组最近报道了利用双光子激光（822 nm）的损害本地个别胚胎斑马鱼肌肉的细胞膜细胞7。 在这里，我们报告使用微点激光（安道尔的技术）在斑马鱼胚胎骨骼肌细胞损伤的方法。微点激光是一种高能量的激光，这是适合于在波长为435nm的靶细胞消融。的激光以这样的方式被连接到显微镜（在我们的设置，光学显微镜从蔡司）显微镜，可以使用在同一时间f或聚焦在样品上的激光和用于可视化的伤人（明或荧光）的影响。用于控制激光脉冲的参数包括波长，强度和脉冲数。 由于其透明度和外部的胚胎发育，斑马鱼胚胎的研究为激光损伤和随后的复苏是非常适合的。受精后1至2天，体节骨骼肌细胞逐渐接受由前向后成熟体节发育的进展，从树干尾8，9。在这些阶段，胚胎自发地抽搐，并开始游泳。最近斑马鱼已被确认为一个重要的脊椎动物模式生物组织再生的研究，许多类型的组织（心脏，神经，血管等）损伤的成年斑马鱼10，11后是可以再生的。

激光介导的损伤进行固定1日龄胚胎。数的激光脉冲在图1中所示，可以生成一个小伤口，由损坏的，盘绕，肌动蛋白丰富的肌原纤维，通常拉伸之间的体节边界容易辨认。然而，较高的激光脉冲造成的大规模破坏的体节块，其中最肌原纤维被破坏。不过，我们可以从字面上遵守“时间可以治愈一切伤口”愈合速度比大的小伤。恢复后，肌动蛋白，肌原纤维染色显示再次跨越正常的体节...

Watch this Scientific Journal Video about Laser-inflicted Injury of Zebrafish Embryonic Skeletal Muscle at JoVE.com

Laser-inflicted Injury of Zebrafish Embryonic Skeletal Muscle

这里介绍的方法，包括精确的具有高能量的激光脉冲和随后的分析随时间的伤害和其恢复损伤的活斑马鱼胚胎。我们还展示了如何转基因标记的单或骨骼肌细胞可以被跟踪和激光损伤后。

激光伤害的斑马鱼胚胎骨骼肌

Various experimental approaches have been used in mouse to induce muscle injury with the aim to study muscle regeneration, including myotoxin injections ...

laser-inflicted-injury-of-zebrafish-embryonic-skeletal-muscle

Research

JoVE Journal

Biology

10.4K 次观看.  Max Delbrück Center for Molecular Medicine. 这里介绍的方法，包括精确的具有高能量的激光脉冲和随后的分析随时间的伤害和其恢复损伤的活斑马鱼胚胎。我们还展示了如何转基因标记的单或骨骼肌细胞可以被跟踪和激光损伤后。

视频: Laser-inflicted Injury of Zebrafish Embryonic Skeletal Muscle

Adult and Embryonic Skeletal Muscle Microexplant Culture and Isolation of Skeletal Muscle Stem Cells

Cultured embryonic and adult skeletal muscle cells have a number of different uses. The micro-dissected explants technique described in this chapter is a robust and reliable method for isolating relatively large numbers of proliferative skeletal muscle cells from juvenile, adult or embryonic muscles as a source of skeletal muscle stem cells. The authors have used micro-dissected explant cultures to analyse the growth characteristics of skeletal muscle cells in wild-type and dystrophic muscles. Each of the components of tissue growth, namely cell survival, proliferation, senescence and differentiation can be analysed separately using the methods described here. The net effect of all components of growth can be established by means of measuring explant outgrowth rates. The micro-explant method can be used to establish primary cultures from a wide range of different muscle types and ages and, as described here, has been adapted by the authors to enable the isolation of embryonic skeletal muscle precursors.
Uniquely, micro-explant cultures have been used to derive clonal (single cell origin) skeletal muscle stem cell (SMSc) lines which can be expanded and used for in vivo transplantation. In vivo transplanted SMSc behave as functional, tissue-specific, satellite cells which contribute to skeletal muscle fibre regeneration but which are also retained (in the satellite cell niche) as a small pool of undifferentiated stem cells which can be re-isolated into culture using the micro-explant method.

The micro-dissected explants technique is a robust and reliable method for isolating proliferative skeletal muscle cells from juvenile, adult or embryonic muscles as a source of skeletal muscle stem cells. Uniquely, these cells have been clonally derived to produce skeletal muscle stem cell lines used for in vivo transplantation.

成人和胚胎骨骼的肌肉Microexplant文化和骨骼肌肉干细胞的分离

Cultured embryonic and adult skeletal muscle cells have a number of different uses. The micro-dissected explants technique described in this chapter is a ...

科研

生物学

Mitochondrial Isolation from Skeletal Muscle

Mitochondria are organelles controlling the life and death of the cell. They participate in key metabolic reactions, synthesize most of the ATP, and regulate a number of signaling cascades2,3. Past and current researchers have isolated mitochondria from rat and mice tissues such as liver, brain and heart4,5. In recent years, many researchers have focused on studying mitochondrial function from skeletal muscles.
Here, we describe a method that we have used successfully for the isolation of mitochondria from skeletal muscles 6. Our procedure requires that all buffers and reagents are made fresh and need about 250-500 mg of skeletal muscle. We studied mitochondria isolated from rat and mouse gastrocnemius and diaphragm, and rat extraocular muscles. Mitochondrial protein concentration is measured with the Bradford assay. It is important that mitochondrial samples be kept ice-cold during preparation and that functional studies be performed within a relatively short time (~1 hr). Mitochondrial respiration is measured using polarography with a Clark-type electrode (Oxygraph system) at 37&deg;C7. Calibration of the oxygen electrode is a key step in this protocol and it must be performed daily. Isolated mitochondria (150 &mu;g) are added to 0.5 ml of experimental buffer (EB). State 2 respiration starts with addition of glutamate (5mM) and malate (2.5 mM). Then, adenosine diphosphate (ADP) (150 &mu;M) is added to start state 3. Oligomycin (1 &mu;M), an ATPase synthase blocker, is used to estimate state 4. Lastly, carbonyl cyanide p-[trifluoromethoxy]-phenyl-hydrazone (FCCP, 0.2 &mu;M) is added to measurestate 5, or uncoupled respiration 6. The respiratory control ratio (RCR), the ratio of state 3 to state 4, is calculated after each experiment. An RCR &ge;4 is considered as evidence of a viable mitochondria preparation.
In summary, we present a method for the isolation of viable mitochondria from skeletal muscles that can be used in biochemical (e.g., enzyme activity, immunodetection, proteomics) and functional studies (mitochondrial respiration).

This protocol describes a procedure to study the respiration of mitochondria isolated from skeletal muscles. This method was adapted from Scorrano et al. (2007). The mitochondrial isolation procedure requires about 2 hours. The mitochondrial respiration can be completed in about 1 hour.

骨骼肌的线粒体分离

Mitochondria are organelles controlling the life and death of the cell. They participate in key metabolic reactions, synthesize most of the ATP, and ...

Purification of Progenitors from Skeletal Muscle

Skeletal muscle contains multiple progenitor populations of distinct embryonic origins and developmental potential. Myogenic progenitors, usually residing in a "satellite cell position" between the myofiber plasma membrane and the laminin-rich basement membrane that ensheaths it, are self-renewing cells that are solely committed to the myogenic lineage1,2. We have recently described a second class of vessel associated progenitors that can generate myofibroblasts and white adipocytes, which responds to damage by efficiently entering proliferation and provides trophic support to myogenic cells during tissue regeneration3,4. One of the most trusted assays to determine the developmental and regenerative potential of a given cell population relies on their isolation and transplantation5-7. To this end we have optimized protocols for their purification by flow cytometry from enzymatically dissociated muscle, which we will outline in this article. The populations obtained using this method will contain either myogenic or fibro/adipogenic colony forming cells: no other cell types are capable of expanding in vitro or surviving in vivo delivery. However, when these populations are used immediately after the sort for molecular analysis (e.g qRT-PCR) one must keep in mind that the freshly sorted subsets may contain other contaminant cells that lack the ability of forming colonies or engrafting recipients.

Method for the enzymatic dissociation, surface labeling and purification by flow cytometry of fibro/adipogenic and myogenic progenitors from murine skeletal muscle.

纯化的骨骼肌的先觉者

Skeletal muscle contains multiple progenitor populations of distinct embryonic origins and developmental potential. Myogenic progenitors, usually residing ...

Analysis of Embryonic and Larval Zebrafish Skeletal Myofibers from Dissociated Preparations

The zebrafish has proven to be a valuable model system for exploring skeletal muscle function and for studying human muscle diseases. Despite the many advantages offered by in vivo analysis of skeletal muscle in the zebrafish, visualizing the complex and finely structured protein milieu responsible for muscle function, especially in whole embryos, can be problematic. This hindrance stems from the small size of zebrafish skeletal muscle (60 &mu;m) and the even smaller size of the sarcomere. Here we describe and demonstrate a simple and rapid method for isolating skeletal myofibers from zebrafish embryos and larvae. We also include protocols that illustrate post preparation techniques useful for analyzing muscle structure and function. Specifically, we detail the subsequent immunocytochemical localization of skeletal muscle proteins and the qualitative analysis of stimulated calcium release via live cell calcium imaging. Overall, this video article provides a straight-forward and efficient method for the isolation and characterization of zebrafish skeletal myofibers, a technique which provides a conduit for myriad subsequent studies of muscle structure and function.

Zebrafish are an emerging system for modeling human disorders of the skeletal muscle. We describe a fast and efficient method to isolate skeletal muscle myofibers from embryonic and larval zebrafish. This method yields a high-density myofiber preparation suitable for study of single skeletal muscle fiber morphology, protein subcellular localization, and muscle physiology.

从解离分析准备胚胎和幼体斑马鱼骨肌纤维

The zebrafish has  proven to be a valuable model system for exploring skeletal muscle function and  for studying human muscle diseases. Despite  the many ...

Analysis of Skeletal Muscle Defects in Larval Zebrafish by Birefringence and Touch-evoke Escape Response Assays

Zebrafish (Danio rerio) have become a particularly effective tool for modeling human diseases affecting skeletal muscle, including muscular dystrophies1-3, congenital myopathies4,5, and disruptions in sarcomeric assembly6,7, due to high genomic and structural conservation with mammals8. Muscular disorganization and locomotive impairment can be quickly assessed in the zebrafish over the first few days post-fertilization. Two assays to help characterize skeletal muscle defects in zebrafish are birefringence (structural) and touch-evoked escape response (behavioral).
Birefringence is a physical property in which light is rotated as it passes through ordered matter, such as the pseudo-crystalline array of muscle sarcomeres9. It is a simple, noninvasive approach to assess muscle integrity in translucent zebrafish larvae early in development. Wild-type zebrafish with highly organized skeletal muscle appear very bright amidst a dark background when visualized between two polarized light filters, whereas muscle mutants have birefringence patterns specific to the primary muscular disorder they model. Zebrafish modeling muscular dystrophies, diseases characterized by myofiber degeneration followed by repeated rounds of regeneration, exhibit degenerative dark patches in skeletal muscle under polarized light. Nondystrophic myopathies are not associated with necrosis or regenerative changes, but result in disorganized myofibers and skeletal muscle weakness. Myopathic zebrafish typically show an overall reduction in birefringence, reflecting the disorganization of sarcomeres.
The touch-evoked escape assay involves observing an embryo&#39;s swimming behavior in response to tactile stimulation10-12. In comparison to wild-type larvae, mutant larvae frequently display a weak escape contraction, followed by slow swimming or other type of impaired motion that fails to propel the larvae more than a short distance12. The advantage of these assays is that disease progression in the same fish type can be monitored in vivo for several days, and that large numbers of fish can be analyzed in a short time relative to higher vertebrates.

The zebrafish is now an established and powerful tool for modeling muscular dystrophies, congenital myopathies, and related neuromuscular diseases. Birefringence and touch-evoked escape behavior are two common noninvasive assays used to determine the degree of muscular disorganization and locomotive impairment of zebrafish embryos during early development.

Zebrafish (Danio rerio) have become a particularly effective tool for modeling human diseases affecting skeletal muscle, including muscular ...

Nephrotoxin Microinjection in Zebrafish to Model Acute Kidney Injury

The kidneys are susceptible to harm from exposure to chemicals they filter from the bloodstream. This can lead to organ injury associated with a rapid decline in renal function and development of the clinical syndrome known as acute kidney injury (AKI). Pharmacological agents used to treat medical circumstances ranging from bacterial infection to cancer, when administered individually or in combination with other drugs, can initiate AKI. Zebrafish are a useful animal model to study the chemical effects on renal function in vivo, as they form an embryonic kidney comprised of nephron functional units that are conserved with higher vertebrates, including humans. Further, zebrafish can be utilized to perform genetic and chemical screens, which provide opportunities to elucidate the cellular and molecular facets of AKI and develop therapeutic strategies such as the identification of nephroprotective molecules. Here, we demonstrate how microinjection into the zebrafish embryo can be utilized as a paradigm for nephrotoxin studies.

Renal injuries incurred from nephrotoxins, which include drugs ranging from antibiotics to chemotherapeutics, can result in complex disorders whose pathogenesis remains incompletely understood. This protocol demonstrates how zebrafish can be used for disease modeling of these conditions, which can be applied to the identification of renoprotective measures.

肾毒素显微注射斑马鱼到模型急性肾损伤

The kidneys are susceptible to harm from exposure to chemicals they filter from the bloodstream. This can lead to organ injury associated with a rapid ...

Electroporation of Plasmid DNA into Mouse Skeletal Muscle

Transient gene expression modulation in murine skeletal muscle by plasmid electroporation is a useful tool for assessing normal and pathological physiology. Overexpression or knockdown of target genes enables investigators to manipulate individual molecular events and, thus, better understand the mechanisms that impact muscle mass, muscle metabolism, and contractility. In addition, electroporation of DNA plasmids that encode fluorescent tags allows investigators to measure changes in subcellular localization of proteins in skeletal muscle in vivo. A key functional assessment of skeletal muscle includes the measurement of muscle contractility. In this protocol, we demonstrate that whole muscle contractility studies are still possible after plasmid DNA injection, electroporation, and gene expression modulation. The goal of this instructional procedure is to demonstrate the step-by-step method of DNA plasmid electroporation into mouse skeletal muscle to facilitate uptake and expression in the myofibers of the tibialis anterior and extensor digitorum longus muscles, as well as to demonstrate that skeletal muscle contractility is not compromised by injection and electroporation.

Electroporation of plasmid DNA into skeletal muscle is a viable method to modulate gene expression without compromising muscle contractility in mice.

将质粒DNA电穿孔到小鼠骨骼肌中

Transient gene expression modulation in murine skeletal muscle by plasmid electroporation is a useful tool for assessing normal and pathological ...

High-Resolution Fluoro-Respirometry of Equine Skeletal Muscle

Mitochondrial function-oxidative phosphorylation and the generation of reactive oxygen species-is critical in both health and disease. Thus, measuring mitochondrial function is fundamental in biomedical research. Skeletal muscle is a robust source of mitochondria, particularly in animals with a very high aerobic capacity, such as horses, making them ideal subjects for studying mitochondrial physiology. This article demonstrates the use of high-resolution respirometry with concurrent fluorometry, with freshly harvested skeletal muscle mitochondria, to quantify the capacity to oxidize substrates under different mitochondrial states and determine the relative capacities of distinct elements of mitochondrial respiration. Tetramethylrhodamine methylester is used to demonstrate the production of mitochondrial membrane potential resulting from substrate oxidation, including calculation of the relative efficiency of the mitochondria by calculating the relative membrane potential generated per unit of concurrent oxygen flux. The conversion of ADP to ATP results in a change in the concentration of magnesium in the reaction chamber, due to differing affinities of the adenylates for magnesium. Therefore, magnesium green can be used to measure the rate of ATP synthesis, allowing the further calculation of the oxidative phosphorylation efficiency (ratio of phosphorylation to oxidation [P/O]). Finally, the use of Amplex UltraRed, which produces a fluorescent product (resorufin) when combined with hydrogen peroxide, allows the quantification of reactive oxygen species production during mitochondrial respiration, as well as the relationship between ROS production and concurrent respiration. These techniques allow the robust quantification of mitochondrial physiology under a variety of different simulated conditions, thus shedding light on the contribution of this critical cellular component to both health and disease.

Horses have an exceptional aerobic exercise capacity, making equine skeletal muscle an important tissue for both the study of equine exercise physiology as well as mammalian mitochondrial physiology. This article describes techniques for the comprehensive assessment of mitochondrial function in equine skeletal muscle.

马骨骼肌的高分辨率氟呼吸测定法

Mitochondrial function-oxidative phosphorylation and the generation of reactive oxygen species-is critical in both health and disease. Thus, measuring ...

通过脱细胞定量骨骼肌脂肪浸润

Decellularization-Based Quantification of Skeletal Muscle Fatty Infiltration

Fatty infiltration is the accumulation of adipocytes between myofibers in skeletal muscle and is a prominent feature of many myopathies, metabolic disorders, and dystrophies. Clinically in human populations, fatty infiltration is assessed using noninvasive methods, including computed tomography (CT), magnetic resonance imaging (MRI), and ultrasound (US). Although some studies have used CT or MRI to quantify fatty infiltration in mouse muscle, costs and insufficient spatial resolution remain challenging. Other small animal methods utilize histology to visualize individual adipocytes; however, this methodology suffers from sampling bias in heterogeneous pathology. This protocol describes the methodology to qualitatively view and quantitatively measure fatty infiltration comprehensively throughout intact mouse muscle and at the level of individual adipocytes using decellularization. The protocol is not limited to specific muscles or specific species and can be extended to human biopsy. Additionally, gross qualitative and quantitative assessments can be made with standard laboratory equipment for little cost, making this procedure more accessible across research laboratories.

作者聚焦：基于脱细胞化的骨骼肌脂肪浸润定量  

The present study describes decellularization-based methodologies for visualizing and quantifying intramuscular adipose tissue (IMAT) deposition through intact muscle volume, as well as quantifying metrics of individual adipocytes that comprise IMAT.

Methods Article

激光伤害的斑马鱼胚胎骨骼肌