The Fralin Life Science Research Institute and The Metabolic Phenotyping Core at Virginia Tech supported this work.

Hayvan çalışmaları Kurumsal Hayvan Bakım tarafından onaylanmış bir protokol çerçevesinde gerçekleştirilen ve Virginia Politeknik Enstitüsü ve Eyalet Üniversitesi&#39;nde Committee bulundu. 1. Kurulum (Saat: ~ 45 dk) <ol><li> 37 ° C su banyosunda Mitokondri (IBM) 1 ve IBM2 için% 0.25 tripsin, İzolasyon Tampon çözülme dondurulmuş saklar. </li><li> Cam ve yüksek saflıkta su ile,% 70 etanol içinde kesme durulayınız. </li><li> 4 bölümden IBM1 1 kısım tripsin seyrelterek% 0.25 tripsin stokundan% 0.05 tripsin çözüm hazırlayın. </li><li> Vidalı kapaklı 1.5 ml mikrosantrifüj tüpü içinde (100 oranı 1) hücre liziz tamponu ile proteaz ve fosfataz inhibitörü kokteyl karıştırın. </li><li> Kısım 5 ml 15 ml&#39;lik plastik tüp içine% 0.05 tripsin (5 ml / fare). </li><li> Set Motor 80 RPM doku homojenleştirici tahrik. </li></ol> İskelet Kası Mitokondri 2. izolasyonu (Saat: ~ 90 dk) <ol><li> CO 2 ile bir fare Euthanize </suservikal dislokasyon b&gt; inhalasyon. </li><li> Aşağıdaki adımlarda açıklandığı gibi soleus (~ 75-100 mg toplam) içeren kuadriseps ve gastroknemius kasının, kırmızı kas kaldırın: <ol><li> Fare doğru cilt soyma. </li><li> Kuadriseps kökenli noktası üzerinde yağ yastığı çıkarın. Ince uçlu makasla patella bağlı olduğu kuadriseps tendonu kesin. Not: quadriceps proksimal femur ön kısmı üzerindeki anatomik pozisyonuna ile tanımlanır. </li><li> Kemik kuadriseps kurtarmak için, femoral arter kaçınarak Yavaşça, kemik ve kuadriseps arasındaki künt snip. Kuadriseps kas özgürleştirmek ve soğutulmuş PBS kuadriseps kas yerleştirmek için femur üzerinde orijin noktasında ince uçlu makasla tendon kesin. </li><li> Makasla kuadriseps üzerinde görünür yağ dokusu çıkarın. Yani femur örten oldu kas kısmı u bakacak şekilde çevirin üzerinde kuadrisepss. Bir yelpaze hareket forseps ile kuadriseps kas açın. Soğutulmuş IBM1 5 ml içeren bir cam kapta ince uçlu makas ve yer ile her lobdan iki görünür kırmızı kas kısımlarını çıkarın. Not: kuadriseps her lobun yan kenarında bulunan kırmızı bir kas şeridi ile iki lob olarak görünür. </li><li> İnce uçlu makasla Aşil tendonu örten deri kesin ve fare doğru cilt soyma. Maruz Aşil tendonu kesin ve fare gövdesine doğru kas soyun. </li><li> Gastroknemius serbest ve soğutulmuş PBS kendi tendon bağlı gastrocnemius yerleştirmek için ince uçlu makasla femur lateral ve medial kondil de tendon kesin. </li><li> Üzerinde gastroknemius ve soleus kas çevirin kalkmasına ve soğutulmuş IBM1 5 ml içeren beher içine yerleştirin. Fan gastroknemius açın. Ince uçlu makas ile üç görsel kırmızı kas kısımlarını (iki yanal ve bir medial yüzeysel kırmızı şeritler) çıkarıns ve soğutulmuş IBM1 5 ml ihtiva eden bir behere aktarın. </li></ol></li><li> (Adım 2.2 de tarif edildiği gibi) fare diğer bacak kırmızı kas diğer ~ 75-100 mg çıkarın ve proteaz ve fosfataz inhibitörü kokteyli ve hücre liziz tamponu (50 mM Tris-HCl, 1 ile 1.5 ml mikrosantrifüj tüpü içine yerleştirmek mM EDTA, 150 mM NaCl,% 1 sodyum dodesil sülfat,% 0.5 sodyum deoksikolat,% 1 polioksietilen (9) nonilfenileter. hemen Western blotlama daha sonra kullanmak için sıvı azot içinde bu ikinci örnek flaş dondurularak dallanmış (adım 6.1). </li><li> Büyük bir kova buz üzerinde önceden soğutulmuş, düz plastik yüzeyi yerleştirin. Plastik yüzeye IBM1 bir damla dökün ve IBM1 damlacık içinde bölümlere kırmızı kas (adım 2.2.4 ve 2.2.7) tüm yerleştirmek için cımbız kullanın. Değişen jilet ile 3 tek kenar jilet her 40 saniye ile 2 dakika süreyle kas dokusu kıyma. </li><li> Th plastik yüzey tutarak taze IBM1, 5 ml ile yeni bir behere kıyılmış doku transfere beher ve bir jilet ile beher içine kas kazıma. Bu çözümü alın ve 50 ml konik tüp yerleştirilir 100 mikron hücre süzgecinden boşaltın. </li><li> Bir hassas bir görev silecek ile doku Blot ve daha sonra% 0.05 tripsin solüsyonu 5 ml aktarın. Görev silecek doku kaldırmak için cımbız kullanın. </li><li> % 0.05 tripsin solüsyonu içinde 30 dakika için buz üzerinde kas dokusu inkübe edin. </li><li> 4 ° C&#39;de 3 dakika boyunca 200 x g&#39;de 15 ml konik tüp içeren tripsin / kas karışımı dönerler. </li><li> Bir atık kabına tripsin süpernatant dökün ve buz 3 ml soğuk IBM1 ile pelletini. 45 ml&#39;lik bir cam homojenizatör tüp doku aktarın. Kalan numune toplamak ve cam homojenleştirici tüp bu eklemek için başka bir 1.5 ml IBM1 ile 15 ml konik tüp durulayın. </li><li> Cam homogenizer beher içinde minimal hareket yani buz ile bir bardak ya da plastik kap dolu yarım içine cam homojenizatör tüp yerleştirin. </li><li&gt; 80 rpm&#39;de 10 geçişle bir motor tahrikli doku homojenleştirici bağlı PTFE havan ile doku / IMB1 homojen bir karışım. ~ 2 saniye, her geçişte alt tutun. </li><li> Yeni 15 ml konik tüp doku Homojenat aktarın ve IBM1 6.5 ml cam homojenizatör tüp durulayın. Doku Homojenat içeren 15 ml konik tüp içine IBM1 dökün. </li><li> 4 ° C&#39;de 10 dakika boyunca 700 g&#39;de 15 ml konik bir tüp dönerler. Yavaşça cam yüksek mukavemetli santrifüj tüpüne süpernatant dökün ve pelet atın. </li><li> 4 ° C&#39;de 10 dakika boyunca 8000 x g&#39;de, yukarıdaki aşamada elde edilen süpernatant dönerler. </li><li> IBM1 Süpernatantı ve yavaşça IBM2 500 ul ekleyerek pelet yeniden askıya. Bir pipet ucunu kesti ve hafifçe karıştırma ve hareketleri karıştırılarak IBM2 pelet homojenize. Pelet tamamen askıya sonra karışıma IBM2 başka 4,5 ml ilave edilir. T gibi büyük pelet parçaları kırarak aşırı öğütme kaçının: Notonun mitokondriyal zarlarının zarar verebilir. </li><li> 4 ° C&#39;de 10 dakika boyunca 8000 x g&#39;de IBM2 / doku Homojenat dönerler. Not: Bu adım, toplam protein içeriğinin katkıda bulunabilir bakiye BSA yana Aşama 4 izole mitokondri daha doğru bir protein ölçümü için temiz bir yüksek mukavemetli santrifüj tüpüne tekrarlanabilir. </li><li> Nazikçe Süpernatantı ve kaldırmak, ancak tamamen kesilmiş olan nokta ile bir pipet ile IBM2 iki 25 ul artışlarını ekleyerek pelet yeniden askıya. Yavaşça karıştırın ve IBM2 25 ul her bir ilaveden sonra pelet karıştırın. Buz üzerinde bu mitokondriyal stok yerleştirin. </li></ol> Tüm Doku Lizat 3. Homojenizasyon (Saat: ~ 45 dakika; Adım sırasında Yapılabilir 7) <ol><li> Bu adım 2.3 sıvı azot içine yerleştirilmiştir gelen kas çıkarın ve tam çözülmüş kadar oda sıcaklığında inkübe edin. </li><li> Ince uçlu makasla buz üzerinde ~ 30 saniye için doku kıyma. </li><li> Zirco iki 100 ul kepçe eklemekıyılmış doku içeren adım 3.2 vidalı kapaklı 1.5 ml mikrosantrifüj tüp uranyum Oksit Boncuk. 4-6 (orta ayar) bir hız ayarında iki 5 ila üç dakika döngüleri kullanarak bir boncuk değirmeni doku homojenleştiricide doku homojenize. </li><li> 4 ° C&#39;de 10 dakika boyunca 12.000 x g&#39;de aşama 3,3 karışımın dönerler. 1.5 ml mikrosantrifüj tüp içine spin ve transferden sonra 1000 ul pipet kullanarak süpernatantı. Pelet atın ve buz üzerinde supernatant yerleştirin. </li></ol> 4. Protein Tayini (süre: ~ 30 dakika) <ol><li> Üreticinin talimatlarına göre BCA Protein tahlil kiti kullanılarak tüm doku lizat (adım 3.4) ve mitokondriyal stokunun (adım 2.17) protein konsantrasyonu belirleyin. </li></ol> 5. Mitokondri Membran Bütünlüğü; Sitrat Sentaz (CS) Etkinlik (Saat: ~ 15 dk) <ol><li> Yüksek saflıkta su mitokondriyal stokunun 20 dilüsyonları: iki ayrı 1 yapın. EklemekTek örnek Triton 100 X% 0,1 ve düşük ayarda (765 Watt, 2 genlik) it at ses dalgalarına maruz. Buz üzerinde başka seyreltme bırakın. Sonikasyon sonra buza örneği dönün. </li><li> Olan bir sitrat sintaz deneyi gerçekleştirmek hem sigara soniklendi ve daha önce tarif edildiği gibi 11,12 bir spektrofotometrik deneyle mitokondriyal dilüsyonları sonike edilmiştir. </li><li> Aşağıdaki denklemleri kullanarak sağlam mitokondri zarlarının yüzdesini belirleyin: (Non-soniklendi CS faaliyeti ÷ soniklendi CS aktivitesi) * 100 </li></ol> 100- N (yüzde yukarıdan elde) 6. Mitokondri İzolasyon Kalite; Western Blot (Saat: Lab Protokole göre) <ol><li> Daha önce açıklandığı gibi 12 tam doku lizat ve izole mitokondri Batı blotting gerçekleştirin. Not: GAPDH kullanımlar primer antikor (1: 1000 seyreltme,% 5 BSA / TBS-T) ve COXIV (1: 1000 seyreltme içinde% 5 yağsızsüt / TBS-T, sırasıyla anti-keçi, tavşan sekonder antikor, (1) ve akabinde: 10,000). </li></ol> 7. Respirometrik Deneyi Run (Saat: ~ 90 dk) <ol><li> Daha önce açıklandığı gibi mikroplaka bazlı O 2 tüketimi ölçüm teknolojisi kullanılarak istenilen Respirometrik tahlilleri yapın (arkadaşı makale ve Rogers bkz ark 8). </li><li> Devlet 4o (RCR) tarafından State 3 bölünmesi veya Devlet 4o Devlet 3U bölerek Solunum kontrol oranı (RCR) belirleyin. RCR belirlerken noktadan noktaya izlerinden orta (ortalama) noktası, ya da en yüksek (Devlet 3) ve en düşük fiyatları (Devlet 4o) kullanın. </li></ol>

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W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Populations+of+rat+skeletal+muscle+mitochondria+after+exercise+and+immobilization.">Populations of rat skeletal muscle mitochondria after exercise and immobilization.</a> J. Appl. Physiol.: Respir., Envir. and Ex. Physiol. 48, 23-28 (1980).</li><li>Asmann, Y. 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=Skeletal+muscle+mitochondrial+functions,+mitochondrial+DNA+copy+numbers,+and+gene+transcript+profiles+in+type+2+diabetic+and+nondiabetic+subjects+at+equal+levels+of+low+or+high+insulin+and+euglycemia.">Skeletal muscle mitochondrial functions, mitochondrial DNA copy numbers, and gene transcript profiles in type 2 diabetic and nondiabetic subjects at equal levels of low or high insulin and euglycemia.</a> Diabetes. 55, 3309-3319 (2006).</li><li>Lanza, I. R., Nair, K. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+assessment+of+isolated+mitochondria+in+vitro.">Functional assessment of isolated mitochondria in vitro.</a> Methods Enzymol. 457, 349-372 (2009).</li></ol>

George Rogers is an employee of Seahorse Bioscience that produces the instrument for which this protocol was modified.

Burada sunulan yöntemler fare iskelet kası minimal miktarlarda (~ 75-100 mg) bir mitokondriyal izolasyon prosedürü ayrıntılı bir açıklamasını sağlar. Bu izolasyon prosedürü O 2 tüketimi oranları, RCR değerleri, maksimal sitrat sentaz aktivitesi ve immunoblotting protein ifadesi ile kanıtlandığı gibi yüksek işleyişi, saf mitokondri (~ 450 mikrogram) elde edebiliyor. Önemli olarak, bu prosedür izole mitokondri, yüksek verimlilik sağlayan mikroplaka göre O2 tüketimi tekno...

The primary function of mitochondria is to produce ATP from oxidative phosphorylation. However, mitochondria have many other important cellular functions including but not limited to: the production and detoxification of reactive oxygen species, the regulation of cytoplasmic and mitochondrial calcium, organelle trafficking, ionic homeostasis, and involvement in apoptosis1,2. Therefore, it is not surprising that dysfunctional mitochondria play a role in many disease pathologies, such as aging, neurodegenerative diseases, cardiovascular disease, cancer, obesity, and diabetes3,4. Importantly, skeletal muscle mitochondria specifically are involved in many of these pathologies3-5.
Mitochondrial respiration assays using isolated mitochondria allow for the assessment of electron transport chain and oxidative phosphorylation function, and the determination of mechanism(s) of action of drugs and proteins that modulate metabolism. Mitochondrial isolation procedures exist for multiple tissue and cell types for a variety of species6,7. However, these procedures often require large quantities of tissue/cells for a high quality mitochondria yield necessary for classic respirometric assays. 
Microplate based respirometirc assays allow for high throughput measurements using minimal quantities of isolated mitochondria, often just several &#181;g per well8. Therefore, we present a modification of previously published methods7 to allow for high quality mitochondria to be isolated from smaller quantities of mouse skeletal muscle for use in microplate based respirometirc assays. In addition, methods are provided to establish the quality of the mitochondrial isolation preparation and the integrity of the mitochondrial membranes. Given that skeletal muscle mitochondria are involved in many pathological conditions, the measurement of O2 consumption in mechanistically driven studies is becoming more prevalent in biomedical research9,10.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>Essentially Fatty</td>
			<td rowspan="2">Sigma Aldrich</td>
			<td rowspan="2">A6003</td>
			<td rowspan="2">N/A</td>
		</tr>
		<tr>
			<td>Acid Free- BSA</td>
		</tr>
		<tr>
			<td>Tris/HCl</td>
			<td>Promega</td>
			<td>H5123</td>
			<td>N/A</td>
		</tr>
		<tr>
			<td>KCL</td>
			<td>Sigma Aldrich</td>
			<td>P9541</td>
			<td>N/A</td>
		</tr>
		<tr>
			<td>Tris Base</td>
			<td>Promega</td>
			<td>H5135</td>
			<td>N/A</td>
		</tr>
		<tr>
			<td>EDTA</td>
			<td>Sigma Aldrich</td>
			<td>E6511</td>
			<td>N/A</td>
		</tr>
		<tr>
			<td>EGTA</td>
			<td>Sigma Aldrich</td>
			<td>E4378</td>
			<td>N/A</td>
		</tr>
		<tr>
			<td>Sucrose</td>
			<td>Sigma Aldrich</td>
			<td>S7903</td>
			<td>N/A</td>
		</tr>
		<tr>
			<td>D-Mannitol</td>
			<td>Sigma Aldrich</td>
			<td>63559</td>
			<td>N/A</td>
		</tr>
		<tr>
			<td>Trypsin-EDTA (0.25%), phenol red</td>
			<td>Thermo Scientific</td>
			<td>25200-056</td>
			<td>N/A</td>
		</tr>
		<tr>
			<td>Sodium Chloride 
			White Crystals or Crystalline Powder 
			&#8805;99.0 %</td>
			<td>Fisher Scientific</td>
			<td>BP3581</td>
			<td>N/A</td>
		</tr>
		<tr>
			<td>Sodium dodecyl sulfate</td>
			<td>Sigma Aldrich</td>
			<td>L3771&#160;</td>
			<td>N/A</td>
		</tr>
		<tr>
			<td>Sodium deoxycholate</td>
			<td>Sigma Aldrich</td>
			<td>D6750&#160;</td>
			<td>N/A</td>
		</tr>
		<tr>
			<td>Polyoxyethylene (12) nonylphenyl ether, branched</td>
			<td>Sigma Aldrich</td>
			<td>238651</td>
			<td>N/A</td>
		</tr>
		<tr>
			<td>Single Edge Razor Blades</td>
			<td>Fisher Scientific</td>
			<td>12-640</td>
			<td>N/A</td>
		</tr>
		<tr>
			<td>Falcon- 100 uM Nylon Cell Strainers</td>
			<td>Fisher Scientific</td>
			<td>352360</td>
			<td>N/A</td>
		</tr>
		<tr>
			<td rowspan="2">Halt Protease &#38; Phosphatse Inhibitor Cocktail</td>
			<td rowspan="2">Thermo Scientific</td>
			<td rowspan="2">1861284</td>
			<td rowspan="2">N/A</td>
		</tr>
		<tr>
		</tr>
		<tr>
			<td rowspan="2">1.5mL microcentrifuge tubes with screw cap</td>
			<td rowspan="2">Thermo Scientific</td>
			<td rowspan="2">3474</td>
			<td rowspan="2">N/A</td>
		</tr>
		<tr>
		</tr>
		<tr>
			<td rowspan="2">Zirconium Oxide beads</td>
			<td rowspan="2">Fisher Scientific</td>
			<td rowspan="2">C9012112</td>
			<td rowspan="2">N/A</td>
		</tr>
		<tr>
		</tr>
		<tr>
			<td>GAPDH antibody (1D4)</td>
			<td>Santa Cruz Biotechnology</td>
			<td>sc-59540</td>
			<td>N/A</td>
		</tr>
		<tr>
			<td>Anti- COXIV antibody</td>
			<td>Cell Signaling</td>
			<td>4844s</td>
			<td>Any mitochondrial inner membrane protein will suffice</td>
		</tr>
		<tr>
			<td rowspan="2">Peroxidase conjugated affinipure Donkey, Anti Rabbit IgG (H+L)</td>
			<td rowspan="2">Jackson ImmunoResearh</td>
			<td rowspan="2">711-035-152</td>
			<td rowspan="2">N/A</td>
		</tr>
		<tr>
		</tr>
		<tr>
			<td rowspan="2">Peroxidase conjugated affinipure Goat, Anti Mouse IgG (H+L)</td>
			<td rowspan="2">Jackson ImmunoResearh</td>
			<td rowspan="2">115-001-003</td>
			<td rowspan="2">N/A</td>
		</tr>
		<tr>
		</tr>
		<tr>
			<td>Triton-X100</td>
			<td>Sigma Aldrich</td>
			<td>X100</td>
			<td>N/A</td>
		</tr>
		<tr>
			<td>Pierce BCA Protein Assay Kit&#160;</td>
			<td>Thermo Scientific</td>
			<td>23225</td>
			<td>N/A</td>
		</tr>
		<tr>
			<td>Pyruvic Acid, 98%</td>
			<td>Sigma Aldrich</td>
			<td>107360</td>
			<td>Store at 4&#176;C,pH to 7.4 with KOH prior to use in respirometric assay</td>
		</tr>
		<tr>
			<td>Succinic Acid</td>
			<td>Sigma Aldrich</td>
			<td>S9512</td>
			<td>Store at room temperature, pH to 7.4 with KOH prior to use in respirometric assay</td>
		</tr>
		<tr>
			<td>L(-) Malic Acid, BioXtra, &#8805;95%</td>
			<td>Sigma Aldrich</td>
			<td>M6413</td>
			<td>Store at room temperature, to 7.4 with KOH prior to use in respirometric assay</td>
		</tr>
		<tr>
			<td rowspan="2">L-Glutamic acid</td>
			<td rowspan="2">Sigma Aldrich</td>
			<td rowspan="2">G1251</td>
			<td rowspan="2">Store at room temperature, to 7.4 with KOH prior to use in respirometric assay, to 7.4 with KOH prior to use in respirometric assay</td>
		</tr>
		<tr>
		</tr>
		<tr>
			<td>Palmitoyl L-carnitine chloride</td>
			<td>Sigma Aldrich</td>
			<td>P1645</td>
			<td>Store at -20&#176;C</td>
		</tr>
		<tr>
			<td>Oligomycin A, &#8805; 95% (HPLC)</td>
			<td>Sigma Aldrich</td>
			<td>75351</td>
			<td>Store at -20&#176;C</td>
		</tr>
		<tr>
			<td>Carbonyl cyanide 4-(trifluoromethoxy)</td>
			<td rowspan="3">Sigma Aldrich</td>
			<td rowspan="3">C2920</td>
			<td rowspan="3">Store at 2-8&#176;C</td>
		</tr>
		<tr>
			<td>phenylhydrazone</td>
		</tr>
		<tr>
			<td>&#8805;98% (TLC), powder [FCCP]</td>
		</tr>
		<tr>
			<td>Antimycin A from streptomyces sp.</td>
			<td>Sigma Aldrich</td>
			<td>A8674</td>
			<td>Store at -20&#176;C</td>
		</tr>
		<tr>
			<td rowspan="2">Adenosine 5&#8242;-diphosphate monopotassium salt dehydrate [ADP]</td>
			<td rowspan="2">Sigma Aldrich</td>
			<td rowspan="2">A5285</td>
			<td rowspan="2">Store at -20&#176;C, to 7.4 with KOH prior to use in respirometric assay</td>
		</tr>
		<tr>
		</tr>
		<tr>
			<td>Rotenone</td>
			<td>Sigma Aldrich</td>
			<td>R8875</td>
			<td>Store at room temperature</td>
		</tr>
	</tbody>
</table>

isolation of mitochondria from minimal quantities of mouse skeletal muscle for high throughput microplate respiratory measurements

Fonksiyonel iskelet kası mitokondri yaşlanma, obezite ve Tip II diyabeti olan gözlenen değiştirilmiş metabolizmasında rol oynar. İzole mitokondriyal müstahzarlardan mitokondriyal respirometrik deneyler, ilaç ve metabolizmasını modüle eden proteinlerin hareket mekanizması (ler) in mitokondriyal fonksiyonun değerlendirilmesi, hem de belirlenmesi için izin verir. Güncel izolasyon prosedürleri genellikle Respirometrik deneyleri için gerekli yüksek kaliteli mitokondri verim dokusunun büyük miktarlarda gerektirir. Bu tarifnamede sunulan yöntemler (~ 450 ug), yüksek verimli, solunum ölçümlerde kullanmak için, fare, iskelet kası, minimum miktarlarda (~ 75-100 mg) izole edilebilir ne kadar kaliteli saflaştırılmıştır mitokondri tarif eder. Bizim izolasyon yöntemi spektrofotometrik sitrat sentaz aktivitesini ölçerek 92.5 ± 2.0% bozulmamış mitokondri verimleri belirlenmiştir. Buna ek olarak, izole edilmiş bir mitokondride Western blot analizi, cytoso soluk ekspresyonu ile sonuçlandılic proteini, GAPDH ve mitokondriyal protein, COXIV sağlam ifadesi. İzole mitokondri belirgin bir GAPDH bantın yokluğu, izolasyon prosedürü sırasında olmayan mitokondriyal kaynaklardan çok az kirlenme göstergesidir. En önemlisi, O 2 tüketimi mikro plakalı tabanlı teknoloji ile hızı ve yüksek birleştiğinde gösterir akuple Respirometrik deneyleri için solunum kontrolü oranı (RCR) belirlenmesi ölçümü (RCR, tüm tahliller için&gt; 6) ve fonksiyonel mitokondri. Sonuç olarak, ayrı bir kıyma adım eklenmesi ve önemli ölçüde daha önce bildirilen yöntemin motor tahrikli homojenleştirme hızını azaltarak yüksek fonksiyonlu teneffüs yüksek bağlanmış mitokondri sonuçlanır fare iskelet kası küçük miktarlarda yüksek kalitede ve saflaştırılmış mitokondri izolasyonunu sağladı mikro-bazlı respirometirc deneyleri sırasında.

Sitrat sintaz aktivitesi sitrat sentez intakt membranlı mitokondri süspansiyonlar içinde mevcut olmamalıdır böylece iç mitokondriyal zarın içinde bulunan ve bu yana membran bütünlüğü için bir ölçüt olarak hizmet vermektedir. 1 sonike ile karşılaştırıldığında sigara sonike mitokondriyal örnekleri sitrat sentaz aktivitesini temsil etmektedir Şekil Aynı izolasyondan örnekler. Sitrat sintaz aktivitesi istatistiksel olarak önemli bir artış mitokondri sonuçla...

Watch this Scientific Journal Video about Isolation of Mitochondria from Minimal Quantities of Mouse Skeletal Muscle for High Throughput Microplate Respiratory Measurements at JoVE.com

Isolation of Mitochondria from Minimal Quantities of Mouse Skeletal Muscle for High Throughput Microplate Respiratory Measurements

Here, we present a modification of a previously reported method that allows for the isolation of high quality and purified mitochondria from smaller quantities of mouse skeletal muscle. This procedure results in highly coupled mitochondria that respire with high function during microplate based respirometirc assays.

Yüksek Verimli Mikroplate Solunum Ölçümler için Fare İskelet Kası Minimal Miktarları gelen Mitokondri İzolasyonu

Dysfunctional skeletal muscle mitochondria play a role in altered metabolism observed with aging, obesity and Type II diabetes. Mitochondrial ...

isolation-mitochondria-from-minimal-quantities-mouse-skeletal-muscle

Research

JoVE Journal

Biology

12.7K Görüntüleme.  Virginia Tech. Here, we present a modification of a previously reported method that allows for the isolation of high quality and purified mitochondria from smaller quantities of mouse skeletal muscle. This procedure results in highly coupled mitochondria that respire with high function during microplate based respirometirc assays.

Video: Isolation of Mitochondria from Minimal Quantities of Mouse Skeletal Muscle for High Throughput Microplate Respiratory Measurements

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.

Yetişkin ve Embriyonik İskelet, Kas Microexplant Kültür ve İskelet Kası Kök Hücre İzolasyonu

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

Biyoloji

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.

İskelet Kası Mitokondrial İzolasyon

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.

İskelet Kası progenitörlerin saflaştırılması

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

Isolation and Culture of Individual Myofibers and their Satellite Cells from Adult Skeletal Muscle

Muscle regeneration in the adult is performed by resident stem cells called satellite cells. Satellite cells are defined by their position between the basal lamina and the sarcolemma of each myofiber. Current knowledge of their behavior heavily relies on the use of the single myofiber isolation protocol. In 1985, Bischoff described a protocol to isolate single live fibers from the Flexor Digitorum Brevis (FDB) of adult rats with the goal to create an in vitro system in which the physical association between the myofiber and its stem cells is preserved 1. In 1995, Rosenblattmodified the Bischoff protocol such that myofibers are singly picked and handled separately after collagenase digestion instead of being isolated by gravity sedimentation 2, 3. The Rosenblatt or Bischoff protocol has since been adapted to different muscles, age or conditions 3-6. The single myofiber isolation technique is an indispensable tool due its unique advantages. First, in the single myofiber protocol, satellite cells are maintained beneath the basal lamina. This is a unique feature of the protocol as other techniques such as Fluorescence Activated Cell Sorting require chemical and mechanical tissue dissociation 7. Although the myofiber culture system cannot substitute for in vivo studies, it does offer an excellent platform to address relevant biological properties of muscle stem cells. Single myofibers can be cultured in standard plating conditions or in floating conditions. Satellite cells on floating myofibers are subjected to virtually no other influence than the myofiber environment. Substrate stiffness and coating have been shown to influence satellite cells' ability to regenerate muscles 8, 9 so being able to control each of these factors independently allows discrimination between niche-dependent and -independent responses. Different concentrations of serum have also been shown to have an effect on the transition from quiescence to activation. To preserve the quiescence state of its associated satellite cells, fibers should be kept in low serum medium 1-3. This is particularly useful when studying genes involved in the quiescence state. In serum rich medium, satellite cells quickly activate, proliferate, migrate and differentiate, thus mimicking the in vivo regenerative process 1-3. The system can be used to perform a variety of assays such as the testing of chemical inhibitors; ectopic expression of genes by virus delivery; oligonucleotide based gene knock-down or live imaging. This video article describes the protocol currently used in our laboratory to isolate single myofibers from the Extensor Digitorum Longus (EDL) muscle of adult mice (6-8 weeks old).

Isolation and culture of myofibers is the gold standard in vitro system to study the transition of satellite cells through quiescence, activation and differentiation. Importantly, the single myofiber culture system preserves the myofiber/stem cell association, which is an essential component of the muscle stem cell niche.

Yetişkin İskelet Kası gelen bireysel Myofibers ve Uydu Hücre İzolasyonu ve Kültür

Muscle  regeneration in the adult is performed by resident stem cells called satellite  cells. Satellite cells are defined by  their position between the ...

Isolation of Blood-vessel-derived Multipotent Precursors from Human Skeletal Muscle

Since the discovery of mesenchymal stem/stromal cells (MSCs), the native identity and localization&#160;of MSCs have been obscured by their retrospective isolation in culture. Recently, using fluorescence-activated cell sorting (FACS), we and other researchers prospectively identified and purified three subpopulations of multipotent precursor cells associated with the vasculature of human skeletal muscle. These three cell populations: myogenic endothelial cells (MECs), pericytes (PCs), and adventitial cells (ACs), are localized respectively to the three structural layers of blood vessels: intima, media, and adventitia. All of these human blood-vessel-derived stem cell (hBVSC) populations not only express classic MSC markers but also possess mesodermal developmental potentials similar to typical MSCs. Previously, MECs, PCs, and ACs have been isolated through distinct protocols and subsequently characterized in separate studies. The current isolation protocol, through modifications to the isolation process and adjustments in the selective cell surface markers, allows us to simultaneously purify all three hBVSC subpopulations by FACS from a single human muscle biopsy. This new method will not only streamline the isolation of multiple BVSC subpopulations but also facilitate future clinical applications of hBVSCs for distinct therapeutic purposes.

Blood vessels within human skeletal muscle harbor several multi-lineage precursor populations that are ideal for regenerative applications. This isolation method allows simultaneous purification of three multipotent precursor cell populations respectively from three structural layers of blood vessels: myogenic endothelial cells from intima, pericytes from media, and adventitial cells from adventitia.

İnsan İskelet Kası Kan-damar-türevli Multipotent Öncüleri İzolasyonu

Since the discovery of mesenchymal stem/stromal cells (MSCs), the native identity and localization&#160;of MSCs have been obscured by their retrospective ...

High-throughput Screening for Chemical Modulators of Post-transcriptionally Regulated Genes

Both transcriptional and post-transcriptional regulation have a profound impact on genes expression. However, commonly adopted cell-based screening assays focus on transcriptional regulation, being essentially aimed at the identification of promoter-targeting molecules. As a result, post-transcriptional mechanisms are largely uncovered by gene expression targeted drug development. Here we describe a cell-based assay aimed at investigating the role of the 3&#39; untranslated region (3&#8217; UTR) in the modulation of the fate of its mRNA, and at identifying compounds able to modify it. The assay is based on the use of a luciferase reporter construct containing the 3&#8217; UTR of a gene of interest stably integrated into a disease-relevant cell line. The protocol is divided into two parts, with the initial focus on the primary screening aimed at the identification of molecules affecting luciferase activity after 24 hr of treatment. The second part of the protocol describes the counter-screening necessary to discriminate compounds modulating luciferase activity specifically through the 3&#8217; UTR. In addition to the detailed protocol and representative results, we provide important considerations about the assay development and the validation of the hit(s) on the endogenous target. The described cell-based reporter gene assay will allow scientists to identify molecules modulating protein levels via post-transcriptional mechanisms dependent on a 3&#8217; UTR.

Here we describe a cell-based reporter gene assay as a valuable tool to screen chemical libraries for compounds modulating post-transcriptional control mechanisms exerted through 3&#8217; UTR.

Post-transkripsiyonel ayarlı genlerin kimyasal Modülatörler için yüksek verimli tarama

Both transcriptional and post-transcriptional regulation have a profound impact on genes expression. However, commonly adopted cell-based screening assays ...

Isolation of Intact Mitochondria from Skeletal Muscle by Differential Centrifugation for High-resolution Respirometry Measurements

Mitochondria are involved in cellular energy metabolism and use oxygen to produce energy in the form of adenosine triphosphate (ATP). Differential centrifugation at low- and high-speed is commonly used to isolate mitochondria from tissues and cultured cells. Crude mitochondrial fractions obtained by differential centrifugation are used for respirometry measurements. The differential centrifugation technique is based on the separation of organelles according to their size and sedimentation velocity. The isolation of mitochondria is performed immediately after tissue harvesting. The tissue is immersed in an ice-cold homogenization medium, minced using scissors and homogenized in a glass homogenizer with a loose-fitting pestle. The differential centrifugation technique is efficient, fast and inexpensive and the mitochondria obtained by differential centrifugation are pure enough for respirometry assays. Some of the limitations and disadvantages of isolated mitochondria, based on differential centrifugation, are that the mitochondria can be damaged during the homogenization and isolation procedure and that large amounts of the tissue biopsy or cultured cells are required for the mitochondrial isolation.

Here, a quadriceps muscle specimen is taken from an anaesthetized pig and mitochondria are isolated by differential centrifugation. Then, the respiratory rates of mitochondrial respiratory chain complexes I, II and IV are determined using high-resolution respirometry.

Yüksek çözünürlüklü Solunum Ölçümleri için Diferansiyel Santrifüj tarafından İskelet Kası Bozulmamış Mitokondri izolasyonu

Mitochondria are involved in cellular energy metabolism and use oxygen to produce energy in the form of adenosine triphosphate (ATP). Differential ...

Isolation and Characterization of Exosomes from Skeletal Muscle Fibroblasts

Exosomes are small extracellular vesicles released by virtually all cells and secreted in all biological fluids. Many methods have been developed for the isolation of these vesicles, including ultracentrifugation, ultrafiltration, and size exclusion chromatography. However, not all are suitable for large scale exosome purification and characterization. Outlined here is a protocol for establishing cultures of primary fibroblasts isolated from adult mouse skeletal muscles, followed by purification and characterization of exosomes from the culture media of these cells. The method is based on the use of sequential centrifugation steps followed by sucrose density gradients. Purity of the exosomal preparations is then validated by western blot analyses using a battery of canonical markers (i.e., Alix, CD9, and CD81). The protocol describes how to isolate and concentrate bioactive exosomes for electron microscopy, mass spectrometry, and uptake experiments for functional studies. It can easily be scaled up or down and adapted for exosome isolation from different cell types, tissues, and biological fluids.

This protocol illustrates the 1) the isolation and culture of primary fibroblasts from the adult mouse gastrocnemius muscle as well as 2) purification and characterization of exosomes using a differential ultracentrifugation method combined with sucrose density gradients followed by western blot analyses.

İskelet Kası Fibroblastlarından Eksozomların İzolasyonu ve Karakterizasyonu

Exosomes are small extracellular vesicles released by virtually all cells and secreted in all biological fluids. Many methods have been developed for the ...

Isolation of High Quality Murine Atrial and Ventricular Myocytes for Simultaneous Measurements of Ca2+ Transients and L-Type Calcium Current

Mouse models play a crucial role in arrhythmia research and allow studying key mechanisms of arrhythmogenesis including altered ion channel function and calcium handling. For this purpose, atrial or ventricular cardiomyocytes of high quality are necessary to perform patch-clamp measurements or to explore calcium handling abnormalities. However, the limited yield of high-quality cardiomyocytes obtained by current isolation protocols does not allow both measurements in the same mouse. This article describes a method to isolate high-quality murine atrial and ventricular myocytes via retrograde enzyme-based Langendorff perfusion, for subsequent simultaneous measurements of calcium transients and L-type calcium current from one animal. Mouse hearts are obtained, and the aorta is rapidly cannulated to remove blood. Hearts are then initially perfused with a calcium-free solution (37 &#176;C) to dissociate the tissue at the level of intercalated discs and afterwards with an enzyme solution containing little calcium to disrupt extracellular matrix (37 &#176;C). The digested heart is subsequently dissected into atria and ventricles. Tissue samples are chopped into small pieces and dissolved by carefully pipetting up and down. The enzymatic digestion is stopped, and cells are stepwise reintroduced to physiologic calcium concentrations. After loading with a fluorescent Ca2+-indicator, isolated cardiomyocytes are prepared for simultaneous measurement of calcium currents and transients. Additionally, isolation pitfalls are discussed and patch-clamp protocols and representative traces of L-type calcium currents with simultaneous calcium transient measurements in atrial and ventricular murine myocytes isolated as described above are provided.

Isolation of High Quality Murine Atrial and Ventricular Myocytes for Simultaneous Measurements of Ca2+ Transients and L-Type Calcium Current

Mouse models allow studying key mechanisms of arrhythmogenesis. For this purpose, high quality cardiomyocytes are necessary to perform patch-clamp measurements. Here, a method to isolate murine atrial and ventricular myocytes via retrograde enzyme-based Langendorff perfusion, which allows simultaneous measurements of calcium-transients and L-type calcium current, is described.

Ca2+ geçici ve L-tipi kalsiyum akımının eşzamanlı ölçümleri için yüksek kaliteli murin atriyal ve ventriküler miyositlerin izolasyonu

Mouse models play a crucial role in arrhythmia research and allow studying key mechanisms of arrhythmogenesis including altered ion channel function and ...

Preparation of Rat Skeletal Muscle Homogenates for Nitrate and Nitrite Measurements

Nitrate ions (NO3-) were once thought to be inert end products of nitric oxide (NO) metabolism. However, previous studies demonstrated that nitrate ions can be converted back to NO in mammals through a two-step reduction mechanism: nitrate being reduced to nitrite (NO2-) mostly by oral commensal bacteria, then nitrite being reduced to NO by several mechanisms including via heme- or molybdenum-containing proteins. This reductive nitrate pathway contributes to enhancing NO-mediated signaling pathways, particularly in the cardiovascular system and during muscular exercise. The levels of nitrate in the body before such utilization are determined by two different sources: endogenous NO oxidation and dietary nitrate intake, principally from plants. To elucidate the complex NO cycle in physiological circumstances, we have examined further the dynamics of its metabolites, nitrate and nitrite ions, which are relatively stable compared to NO. In previous studies skeletal muscle was identified as a major storage organ for nitrate ions in mammals, as well as a direct source of NO during exercise. Therefore, establishing a reliable methodology to measure nitrate and nitrite levels in skeletal muscle is important and should be helpful in extending its application to other tissue samples. This paper explains in detail the preparation of skeletal muscle samples, using three different homogenization methods, for nitrate and nitrite measurements and discusses important issues related to homogenization processes, including the size of the samples. Nitrate and nitrite concentrations have also been compared across four different muscle groups.

We present protocols for three different methods for the homogenization of four different muscle groups of rat skeletal muscle tissue to measure and compare the levels of nitrate and nitrite. Furthermore, we compare different sample weights to investigate whether tissue sample size affects the results of homogenization.

Nitrat ve Nitrit Ölçümleri için Sıçan İskelet Kas Homojenatlarının Hazırlanması

Nitrate ions (NO3-) were once thought to be inert end products of nitric oxide (NO) metabolism. However, previous studies demonstrated that nitrate ions ...