This work was supported by National Institutes of Health Grants R00 HL112952 (to R. H.), R01 HL108618 (to J.P.G.), P01 HL051971, and P20 GM104357. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

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The authors declare that they have no competing financial interests.

위의 프로토콜을 동시에 분리 작업 쥐 심장 글루코스 산화 및 지방산 산화를 통해 기판의 광속을 정량화하는 방법을 자세히. 측정은 (... 등의 부하 변화, 허혈 재관류) 기준선 스트레스 조건 하에서 기판 대사 심장 워크 간의 관계를 결정하기 위해 기록 된 심장 기능 파라미터에 중첩 될 수있다. 이는 대사 / 수축 관계 심부전 및 당뇨병과 같은 기존의 상태에 의해 영향을받는 방법을 평가하?...

임상 관련성 포유 동물의 심장에서 산화 적 대사 경로, ATP 생성과 심장 작품 (1)을 통해 기판의 플럭스 사이에 강한 긍정적 인 관계가있다. 지난 20 년 동안 심장 대사와 기능 사이의 복잡한 링크의 조사는 심장 대사의 변화는 심장 질환 2-4의 다른 유형의 설정에서 수축 기능 장애 가능성이 병리학 적 구조 리모델링에 대한 원인을 인식하게되었다. 따라서, 스트레인 된 심장의 대사 리모델링을 관리하는 메커니즘에 대한 이해 심부전 5-7의 예방 또는 치료를위한 치료 표적의 확인을 초래할 것으로 예상된다. &quot;심장 대사의 평가&quot;에 미국 심장 협회에서 과학적 진술의 최근 간행물은 t에 대한 과학계의 관심이 점점 강조연구 (8) 자신의 분야. 심장 이미징 기술의 진보는 이제 심장 형태와 기능의 신속하고 정확한 평가를 허용 반면, 심장 대사의 생체 내 연구는 제한적이고 부담이 남아있다 : 핵 자기 공명 (NMR) 분광법과 양전자 방출 단층 촬영 (PET) 영상 수 생체 외 날짜 .TO 정상 상태 조건에서 산화 대사에 대한 다양한 기판 기여 9 판별 심장 고 에너지 인산 대사 크렙스 회로 활동을 수행하는데 사용될 수 있지만, 이러한 기술들은 높은 운영 비용으로 자신의 무능력 퍼진 마음의 준비 작업을 동시에 실시간으로, 산화 적 대사 경로 7,9에 수축 기능과 기판의 플럭스에서 공부하는 유일하고 독특한 기술을 사용할 나타냅니다. 다음 프로토콜 래트를 결정하는데 사용될 시약의 제조 및 이용의 지침을 제공하는 것이다격리 된 작업 쥐의 심장에 기판 활용 말이지. 격리 된 작업 쥐 심장 장치 기술은 반세기 이전이지만, 분리 작업 쥐 심장 제제는 심혈관 연구를 선택하는 방법을 남아있다. 랑겐 돌프 심장 제조와 마찬가지로 작용 쥐 심장 신경 호르몬 다른 장기와 다른 순환 계수의 교란 효과는 독립적으로 심장의 다양한 파라미터를 측정 할 수있는 비교적 간단한 신뢰성 있고 저렴한 방법을 제공한다. 그러나 랑겐 돌프 - 관류 마음 대조적으로, 작업 심장에 가까운 생리 심장 연구, 생체 조건에 관련이있는 수준으로 산화 대사 플럭스의 생성을위한 전제 조건을 수행하고 있습니다. 이것은 좌심방 접속 캐뉼라를 통해 좌심실 (LV)로 관류 버퍼를 제공함으로써 달성되고 LV는 채우고 계약으로되어버퍼가 결정된 후 부하 수압에 대한 대동맥 라인을 통해 배출됩니다. 원래 10 이후 Taegtmeyer, HEMS와 크렙스 (11)에 의해 개선 되었으나 닐리와 동료에 의해 기술 된 관류 장치의 디자인은 이후 약간 변경되었습니다. 원래 장치에서 설명한 바와 같이, 수축 기능은 대동맥 측정하기 위해 더 이상 메스 실린더 및 스톱워치를 사용하지 않고, 심 박출량의 측정을 통해 평가 될 수 있고, 관상 동맥은 10, 11을 흐른다. 여러 벤더가 완료 작업 쥐 심장 관류 시스템을 제공합니다. 이들 시판되는 장치 flowprobes, 압력 센서, 압력 볼륨 카테터와 심장 기능의 데이터 수집과 분석에 필요한 모든 장비를 얻을 수있다. 공급 업체는 장비와 새로운 사용자 익숙해 광범위한 문서 및 교육 세션을 제공합니다. 작업 심장기구도에 여러 또한 리뷰 기사 상세 프로토콜[슬라이드 쇼와 카테터의 사용에 설치류 12-15에서 심장 기능을 측정합니다. 이러한 이유로, 우리는 잠시 관류 장치 및 기록 장치의 설정을 언급한다. 본 프로토콜은 다소 동시에 포도당과 장쇄 지방산 산화의 속도는 정상적인 심장의 두 가지 에너지를 제공하는 기판을 측정하도록 구현 될 수있는 방법에 대한 설명과 함께 이미 이용 가능한 정보를 보완하는 것이다. 우리는 데이터 분석 샘플의 회수 및 처리 시약 및 버퍼의 제조에서, 심근 산화 대사 평가 방사성 에너지 기판의 사용에 관련된 현재의 모든 단계를 설명한다. 이 방법의 원리 심근 (glucos를 지방산 (주로 장쇄 지방산)과 탄수화물의 산화 적 인산화의 수축 에너지의 대부분을 생성전자 및 락 테이트). 심장은 매우 정력 보유 제한 및 순환에서 이러한 에너지 제공 기판의 지속적인 공급에 의존하고있다. 당분 경로를 통한 글루코오스의 이화는 미토콘드리아 내막의 피루 베이트 탈수소 효소 복합체에 의해 탈 카복실 화되는 피루브산을 산출한다. 알부민 또는 지단백질 순환하는 트리글리세리드에서 추출한 장쇄 지방산은 제 세포질에서 아실 CoA를 분자로 활성화되고,이어서 베타 산화 경로를 입력 카르니틴 셔틀 통하여 미토콘드리아 기질 내부에 반송된다. 포도당 지방산의 분해 작용에 의해 생성 된 아세틸 -CoA 분자 미토콘드리아 내막을 가로 질러 양성자 원동력을 구축하는 전자 전달계에 사용되는 환원 등가물 (NADH와 FADH 2)를 생성하는 크렙스 회로 연료 및 ATP에 합성 효소의 활동을 통해 ATP를 생성합니다. 물과 이산화탄소의 단부 부산물이다크렙스 사이클 내에서 일어나는 효소 반응. 14 C- 3 H- 방사성 표지 된 기질의 공급은 절연 작업 심장 (예 : C-14 방사성 표지 된 글루코스, 3 H-방사성 올레산) 따라서 14 CO 2, 3 H 2 O의 생산을 유도 할 수있다 정량적 관상 동맥 유출 물로부터 회복 될 수있다. 14 CO 2의 컬렉션은 밀폐 챔버에 격리 관류 심장을 유지하여 그것을 중심을 빠져 나올 때 바로 관상 동맥 유출 물을 회수하여 실시된다. 작은 음이온 교환 컬럼 분리하여 관상 동맥 유출 물로부터 3 H 2 O를 복구하기 위해 사용된다. 처리 된 샘플의 방사능을 액체 섬광 계수기로 측정 한 결과, 사용 된 방사성 표지 된 기질의 특정 활성의 기술로, 개별적으로 포도당과 지방산의 광속을 정량하는 것이 가능하다산화는 16, 17을 경로.

<table><tbody><tr><td>Sodium Chloride (NaCl)</td><td>Fisher Scientific</td><td>BP358</td><td></td></tr><tr><td>Potassium Chloride (KCl)</td><td>Fisher Scientific</td><td>BP366</td><td></td></tr><tr><td>Potassium Phosphate Monobasic (KH&lt;sub&gt;2&lt;/sub&gt;PO&lt;sub&gt;4&lt;/sub&gt;)</td><td>Fisher Scientific</td><td>P284</td><td></td></tr><tr><td>Magnesium Sulfate Heptahydrate (MgSO&lt;sub&gt;4&lt;/sub&gt;*7H&lt;sub&gt;2&lt;/sub&gt;O)</td><td>Fisher Scientific</td><td>M63</td><td></td></tr><tr><td>Sodium Bicarbonate (NaHCO&lt;sub&gt;3&lt;/sub&gt;)</td><td>Fisher Scientific</td><td>S233</td><td></td></tr><tr><td>Calcium Chloride (CaCl&lt;sub&gt;2&lt;/sub&gt;)</td><td>Sigma-Aldrich</td><td>C5670</td><td></td></tr><tr><td>AG 1-X8 resin, chloride form, 100 - 200 dry mesh size, 500 g</td><td>Bio-Rad</td><td>1401441</td><td>This item can be replaced by purchasing directly the hydoxide form&amp;nbsp; (see reference below), but this will cost almost 8 times more</td></tr><tr><td>AG 1-X8 resin, hydroxide form, 100 - 200 dry mesh size, 100 g</td><td>Bio-Rad</td><td>1432445</td><td>Purchasing this item allows to bypass the conversion of the anion exchange resin from the chloride form to the hydroxide form (See section 1.2 of protocol)</td></tr><tr><td>Glass Microanalysis Vacuum Filter Holder</td><td>Fisher Scientific</td><td>09-753-2</td><td></td></tr><tr><td>Sodium Hydroxide (NaOH)</td><td>Fisher Scientific</td><td>S318</td><td>Corrosive. Consult the product MSDS for appropriate handling and storage.</td></tr><tr><td>Gas Dispersion Tube with Fritted Cylinder</td><td>Fisher Scientific</td><td>11-138B</td><td></td></tr><tr><td>Probumin Bovine Serum Albumin Fatty Acid Free, Powder</td><td>EMD Millipore</td><td>820027</td><td>We recommend the use of a charcoal-defatted BSA, as other purification process such as cold ethanol fractionation may leave residues toxic for the heart.</td></tr><tr><td>Sodium Oleate</td><td>Sigma-Aldrich</td><td>O7501</td><td></td></tr><tr><td>Oleic Acid, [9,10-&lt;sup&gt;3&lt;/sup&gt;H(N)]-</td><td>PerkinElmer</td><td>NET289005MC</td><td>Radioactive material. Follow your Institution&#039;s radiation safety office guidelines for ordering and handling.</td></tr><tr><td>Dialysis Membrane Tubing, 29 mm diameter</td><td>Fisher Scientific</td><td>08-667E</td><td></td></tr><tr><td>D-(+)-Glucose</td><td>Sigma-Aldrich</td><td>G7021</td><td></td></tr><tr><td>Glucose, D-[14C(U)]-</td><td>PerkinElmer</td><td>NEC042B005MC</td><td>Radioactive material. Follow your Institution&#039;s radiation safety office guidelines for ordering and handling.</td></tr><tr><td>Humulin R U-100</td><td>Eli Lilly and Company</td><td>NDC 0002-8215-01 (HI-210)</td><td></td></tr><tr><td>Inactin Hydrate</td><td>Sigma-Aldrich</td><td>T133</td><td>Controlled substance on USDEA Schedule III</td></tr><tr><td>3-0 Silk Black Braid</td><td>Roboz Surgical</td><td>SUT-15-3</td><td></td></tr><tr><td>10x Hyamine Hydroxide</td><td>PerkinElmer</td><td>6003005</td><td>Highly toxic and causes severe burns. Consult the product MSDS for appropriate handling and storage</td></tr><tr><td>20 ml Glass Scintillation Vials</td><td>Fisher Scientific</td><td>03-341-25E</td><td>Use glass vials for quantitative recovery of &lt;sup&gt;14&lt;/sup&gt;CO&lt;sub&gt;2&lt;/sub&gt;</td></tr><tr><td>20 ml HDPE Scintillation Vials</td><td>Fisher Scientific</td><td>03-337-23B</td><td>Use HDPE vials for quantitative recovery of &lt;sup&gt;3&lt;/sup&gt;H&lt;sub&gt;2&lt;/sub&gt;O</td></tr><tr><td>Red Rubber Sleeve Stoppers</td><td>Fisher Scientific</td><td>14-126DD</td><td>Fit 20 mL scintillation vials; Reusable</td></tr><tr><td>BD PrecisionGlide Needle 23G x 40 mm</td><td>BD</td><td>305194</td><td>Use to inject perchloric acid through the rubber sleeve stopper of the CO&lt;sub&gt;2&lt;/sub&gt; trap</td></tr><tr><td>Perchloric Acid, 60%</td><td>Fisher Scientific</td><td>A228</td><td>Highly corrosive and may act as an oxidizer and/or cause an explosion hazard. Consult the product MSDS for appropriate handling and storage</td></tr><tr><td>Ultima Gold, Scintillation Cocktail</td><td>PerkinElmer</td><td>6013327</td><td></td></tr><tr><td>Glass Wool</td><td>Fisher Scientific</td><td>AC38606</td><td></td></tr><tr><td>Decon Dri-Clean Detergent Powder</td><td>Fisher Scientific</td><td>04-355</td><td>For cleaning of glassware, plastic parts, and tubing</td></tr><tr><td>Alconox Tergazyme Enzyme-Active Powered Detergent</td><td>Fisher Scientific</td><td>16-000-115</td><td>For cleaning of &quot;hard to reach&quot; surfaces (tubing, glassware) contaminated by fatty acid-BSA residue</td></tr></tbody></table>

methods for the determination of rates of glucose and fatty acid oxidation in the isolated working rat heart

포유류 마음은 ATP의 주요 소비자이며, 수축의 에너지 기판의 지속적인 공급이 필요합니다. 당연히 심근 대사의 변화가 수축 부전 심부전의 개발과 연결되어있다. 따라서, 신진 대사 및 수축 사이의 링크를 푸는 것은 질병 상태에서 심장 적응 또는 부적응을 지배하는 메커니즘의 일부에 빛을 흘렸다한다. 분리 된 래트 심장 작동 준비를 동시에 실시간 심장 수축 기능 및 산화 적 대사 경로에 기판을 제공하는 에너지의 흐름에 따라 사용될 수있다. 본 프로토콜은 포도당 지방산, 심장의 기판을 제공하는 주된 에너지 산화 비율의 정량적 측정을 위해 버퍼의 제조 및 이용에 사용되는 방법에 대한 상세한 설명을 제공하는 것을 목적으로한다. 시료 분석 및 데이터 해석에 사용되는 방법에 대해서도 설명합니다.간단히 말해서,이 기술은 정상 체온 결정질 관류 통해 생체 심장 박동로 (14)의 공급 C- 방사성 포도당과 3 H- 방사성 장쇄 지방산에 기초한다. 14 CO 2, 3 H 2 O, 최종 부산물 이러한 에너지 제공 기판의 사용에 관여하는 효소 반응은 다음 정량적 관상 동맥 유출 물로부터 회수된다. 사용되는 방사성 표지 된 기질의 특정 활성의 기술로, 개별적으로 산화 경로에 포도당과 지방산의 광속을 정량하는 것이 가능하다. 분리 된 심장의 수축 기능은 해당 기록 장치와 병렬로 결정될 직접 대사 플럭스 값과 상관 될 수있다. 이 기술은 사전에로드 및 국소 빈혈, 약물 또는 circula 후 변경 등 다양한 스트레스 조건에 대한 응답으로 대사 / 수축 관계를 연구하는 것이 매우 유용하다유전자 산물의 발현의 변화 다음 팅 계수 나.

두 대표 실험은 아래 그림에 설명되어 있습니다. 두 경우 모두, 16 주령의 수컷 스프 라그 돌리 래트의 심장을 분리하고, 선행하는 프로토콜에 따라 제조 KH 완충액 작업 모드 관류. 각 실험에서, 심장 심장 작업에 영향을 미치는 응력 상태로 하였다. 심장 수축 기능 대동맥 라인의 압력 센서의 삽입을 통해 심장의 전력 측정하여 맥압의 연속 촬영에 의해 평가 하였다. 에너?...

Watch this Scientific Journal Video about Methods for the Determination of Rates of Glucose and Fatty Acid Oxidation in the Isolated Working Rat Heart at JoVE.com

Methods for the Determination of Rates of Glucose and Fatty Acid Oxidation in the Isolated Working Rat Heart

The following protocol describes the preparation and utilization of buffers for the quantitative measurement of rates of glucose and fatty acid oxidation in the isolated working rat heart. The methods used for sample analysis and data interpretation are also discussed.

격리 된 작업 쥐의 심장에서 포도당과 지방산 산화의 가격의 결정 방법

The mammalian heart is a major consumer of ATP and requires a constant supply of energy substrates for contraction. Not surprisingly, alterations of ...

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14.6K 조회수.  University of Mississippi Medical Center. The following protocol describes the preparation and utilization of buffers for the quantitative measurement of rates of glucose and fatty acid oxidation in the isolated working rat heart. The methods used for sample analysis and data interpretation are also discussed.

비디오: Methods for the Determination of Rates of Glucose and Fatty Acid Oxidation in the Isolated Working Rat Heart

Using Isolated Mitochondria from Minimal Quantities of Mouse Skeletal Muscle for High throughput Microplate Respiratory Measurements

Skeletal muscle mitochondria play a specific role in many disease pathologies. As such, the measurement of oxygen consumption as an indicator of mitochondrial function in this tissue has become more prevalent. Although many technologies and assays exist that measure mitochondrial respiratory pathways in a variety of cells, tissue and species, there is currently a void in the literature in regards to the compilation of these assays using isolated mitochondria from mouse skeletal muscle for use in microplate based technologies. Importantly, the use of microplate based respirometric assays is growing among mitochondrial biologists as it allows for high throughput measurements using minimal quantities of isolated mitochondria. Therefore, a collection of microplate based respirometric assays were developed that are able to assess mechanistic changes/adaptations in oxygen consumption in a commonly used animal model. The methods presented herein provide step-by-step instructions to perform these assays with an optimal amount of mitochondrial protein and reagents, and high precision as evidenced by the minimal variance across the dynamic range of each assay.

The methods presented provide step-by-step instructions for the performance of a collection of microplate based respirometric assays using isolated mitochondria from minimal quantities of mouse skeletal muscle. These assays are able to measure mechanistic changes/adaptations in mitochondrial oxygen consumption in a commonly used animal model.

높은 처리량 마이크로 호흡 측정을위한 마우스 골격근의 최소 수량에서 미토콘드리아 격리 사용

Skeletal muscle mitochondria play a specific role in many disease pathologies. As such, the measurement of oxygen consumption as an indicator of ...

연구

발생학

NADH Fluorescence Imaging of Isolated Biventricular Working Rabbit Hearts

Since its inception by Langendorff1, the isolated perfused heart remains a prominent tool for studying cardiac physiology2. However, it is not well-suited for studies of cardiac metabolism, which require the heart to perform work within the context of physiologic preload and afterload pressures. Neely introduced modifications to the Langendorff technique to establish appropriate left ventricular (LV) preload and afterload pressures3. The model is known as the isolated LV working heart model and has been used extensively to study LV performance and metabolism4-6. This model, however, does not provide a properly loaded right ventricle (RV). Demmy et al. first reported a biventricular model as a modification of the LV working heart model7, 8. They found that stroke volume, cardiac output, and pressure development improved in hearts converted from working LV mode to biventricular working mode8. A properly loaded RV also diminishes abnormal pressure gradients across the septum to improve septal function. Biventricular working hearts have been shown to maintain aortic output, pulmonary flow, mean aortic pressure, heart rate, and myocardial ATP levels for up to 3 hours8.
When studying the metabolic effects of myocardial injury, such as ischemia, it is often necessary to identify the location of the affected tissue. This can be done by imaging the fluorescence of NADH (the reduced form of nicotinamide adenine dinucleotide)9-11, a coenzyme found in large quantities in the mitochondria. NADH fluorescence (fNADH) displays a near linearly inverse relationship with local oxygen concentration12 and provides a measure of mitochondrial redox state13. fNADH imaging during hypoxic and ischemic conditions has been used as a dye-free method to identify hypoxic regions14, 15 and to monitor the progression of hypoxic conditions over time10.
The objective of the method is to monitor the mitochondrial redox state of biventricular working hearts during protocols that alter the rate of myocyte metabolism or induce hypoxia or create a combination of the two. Hearts from New Zealand white rabbits were connected to a biventricular working heart system (Hugo Sachs Elektronik) and perfused with modified Krebs-Henseleit solution16 at 37 &deg;C. Aortic, LV, pulmonary artery, and left &amp; right atrial pressures were recorded. Electrical activity was measured using a monophasic action potential electrode. To image fNADH, light from a mercury lamp was filtered (350&plusmn;25 nm) and used to illuminate the epicardium. Emitted light was filtered (460&plusmn;20 nm) and imaged using a CCD camera. Changes in the epicardial fNADH of biventricular working hearts during different pacing rates are presented. The combination of the heart model and fNADH imaging provides a new and valuable experimental tool for studying acute cardiac pathologies within the context of realistic physiological conditions.

The objective is to monitor the mitochondrial redox state of isolated hearts within the context of physiologic preload and afterload pressures. A biventricular working rabbit heart model is presented. High spatiotemporal resolution fluorescence imaging of NADH is used to monitor the mitochondrial redox state of epicardial tissue.

절연 Biventricular의 NADH 형광 이미징은 토끼 하트 워킹

Since its inception by Langendorff1, the isolated perfused heart remains a prominent tool for studying cardiac physiology2. However, it is not well-suited ...

의학

Measurement of Fatty Acid &#946;-Oxidation in a Suspension of Freshly Isolated Mouse Hepatocytes

Fatty acid &#946;-oxidation is a key metabolic pathway to meet the energy demands of the liver and provide substrates and cofactors for additional processes, such as ketogenesis and gluconeogenesis, which are essential to maintain whole-body glucose homeostasis and support extra-hepatic organ function in the fasted state. Fatty acid &#946;-oxidation occurs within the mitochondria and peroxisomes and is regulated through multiple mechanisms, including the uptake and activation of fatty acids, enzyme expression levels, and availability of cofactors such as coenzyme A and NAD+. In assays that measure fatty acid &#946;-oxidation in liver homogenates, cell lysis and the common addition of supraphysiological levels of cofactors mask the effects of these regulatory mechanisms. Furthermore, the integrity of the organelles in the homogenates is hard to control and can vary significantly between preparations. The measurement of fatty acid &#946;-oxidation in intact primary hepatocytes overcomes the above pitfalls. This protocol describes a method for the measurement of fatty acid &#946;-oxidation in a suspension of freshly isolated primary mouse hepatocytes incubated with 14C-labeled palmitic acid. By avoiding hours to days of culture, this method has the advantage of better preserving the protein expression levels and metabolic pathway activity of the original liver, including the activation of fatty acid &#946;-oxidation observed in hepatocytes isolated from fasted mice compared to fed mice.

Fatty acid &#946;-oxidation is an essential metabolic pathway responsible for generating energy in many different cell types, including hepatocytes. Here, we describe a method to measure fatty acid &#946;-oxidation in freshly isolated primary hepatocytes using 14C-labeled palmitic acid.

갓 분리된 마우스 간세포의 현탁액에서의 지방산 β산화의 측정

Fatty acid &#946;-oxidation is a key metabolic pathway to meet the energy demands of the liver and provide substrates and cofactors for additional ...

생화학

An Optimized Protocol to Analyze Glycolysis and Mitochondrial Respiration in Lymphocytes

Lymphocytes respond to a variety of stimuli by activating intracellular signaling pathways, which in turn leads to rapid cellular proliferation, migration and differentiation, and cytokine production. All of these events are tightly linked to the energy status of the cell, and therefore studying the energy-producing pathways may give clues about the overall functionality of these cells. The extracellular flux analyzer is a commonly used device for evaluating the performance of glycolysis and mitochondrial respiration in many cell types. This system has been used to study immune cells in a few published reports, yet a comprehensive protocol optimized particularly for lymphocytes is lacking. Lymphocytes are fragile cells that survive poorly in ex vivo conditions. Oftentimes lymphocyte subsets are rare, and working with low cell numbers is inevitable. Thus, an experimental strategy that addresses these difficulties is required. Here, we provide a protocol that allows for rapid isolation of viable lymphocytes from lymphoid tissues, and for the analysis of their metabolic states in the extracellular flux analyzer. Furthermore, we provide results of experiments in which the metabolic activities of several lymphocyte subtypes at different cell densities were compared. These observations suggest that our protocol can be used to achieve consistent, well-standardized results even at low cell concentrations, and thus it may have broad applications in future studies focusing on the characterization of metabolic events in immune cells.

The study of metabolism is becoming increasingly relevant to immunological research. Here, we present an optimized method for measuring glycolysis and mitochondrial respiration in mouse splenocytes, and T and B lymphocytes.

최적화 된 프로토콜은 림프구에 해당 작용과 미토콘드리아 호흡을 분석하는

Lymphocytes respond to a variety of stimuli by activating intracellular signaling pathways, which in turn leads to rapid cellular proliferation, migration ...

면역학 및 감염병학

Intra-cardiac Side-Firing Light Catheter for Monitoring Cellular Metabolism using Transmural Absorbance Spectroscopy of Perfused Mammalian Hearts

Absorbance spectroscopy of cardiac muscle provides non-destructive assessment of cytosolic and mitochondrial oxygenation via myoglobin and cytochrome absorbance respectively. In addition, numerous aspects of the mitochondrial metabolic status such as membrane potential and substrate entry can also be estimated. To perform cardiac wall transmission optical spectroscopy, a commercially available side-firing optical fiber catheter is placed in the left ventricle of the isolated perfused heart as a light source. Light passing through the heart wall is collected with an external optical fiber to perform optical spectroscopy of the heart in near real- time. The transmission approach avoids numerous surface scattering interference occurring in widely used reflection approaches. Changes in transmural absorbance spectra were deconvolved using a library of chromophore reference spectra, providing quantitative measures of all the known cardiac chromophores simultaneously. This spectral deconvolution approach eliminated intrinsic errors that may result from using common dual wavelength methods applied to overlapping absorbance spectra, as well as provided a quantitative evaluation of the goodness of fit. A custom program was designed for data acquisition and analysis, which permitted the investigator to monitor the metabolic state of the preparation during the experiment. These relatively simple additions to the standard heart perfusion system provide a unique insight into the metabolic state of the heart wall in addition to conventional measures of contraction, perfusion, and substrate/oxygen extraction.

Here we introduce a method for using an intra-ventricle optical catheter in perfused hearts to perform absorbance spectroscopy across the heart wall. The data obtained provides robust information on tissue oxygen tension as well as substrate utilization and membrane potential simultaneously with cardiac performance measures in this ubiquitous preparation.

교란 성 포유류 심장의 경부 흡광도 분광학을 사용하여 세포 대사를 모니터링하기위한 심장 내 측 발사 라이트 카테터

Absorbance spectroscopy of cardiac muscle provides non-destructive assessment of cytosolic and mitochondrial oxygenation via myoglobin and cytochrome ...

생체공학

Analyzing Oxygen Consumption Rate in Primary Cultured Mouse Neonatal Cardiomyocytes Using an Extracellular Flux Analyzer

Mitochondria and oxidative metabolism are critical for maintaining cardiac muscle function. Research has shown that mitochondrial dysfunction is an important contributing factor to impaired cardiac function found in heart failure. By contrast, restoring defective mitochondrial function may have beneficial effects to improve cardiac function in the failing heart. Therefore, studying the regulatory mechanisms and identifying novel regulators for mitochondrial function could provide insight which could be used to develop new therapeutic targets for treating heart disease. Here, cardiac myocyte mitochondrial respiration is analyzed using a unique cell culture system. First, a protocol has been optimized to rapidly isolate and culture high viability neonatal mouse cardiomyocytes. Then, a 96-well format extracellular flux analyzer is used to assess the oxygen consumption rate of these cardiomyocytes. For this protocol, we optimized seeding conditions and demonstrated that neonatal mouse cardiomyocytes oxygen consumption rate can be easily assessed in an extracellular flux analyzer. Finally, we note that our protocol can be applied to a larger culture size and other studies, such as intracellular signaling and contractile function analysis.

The goal of this protocol is to illustrate how to use mouse neonatal cardiomyocytes as a model system to examine how various factors can alter oxygen consumption in the heart.

세포 외 유출 분석기를 사용 하 여 기본 교양된 마우스 신생아 Cardiomyocytes에 산소 소비 속도 분석

Mitochondria and oxidative metabolism are critical for maintaining cardiac muscle function. Research has shown that mitochondrial dysfunction is an ...

Determination of Mitochondrial Respiration and Glycolysis in Ex Vivo Retinal Tissue Samples

Mitochondrial respiration is a critical energy-generating pathway in all cells, especially retinal photoreceptors that possess a highly active metabolism. In addition, photoreceptors also exhibit high aerobic glycolysis like cancer cells. Precise measurements of these metabolic activities can provide valuable insights into cellular homeostasis under physiological conditions and in disease states. High throughput microplate-based assays have been developed to measure mitochondrial respiration and various metabolic activities in live cells. However, a vast majority of these are developed for cultured cells and have not been optimized for intact tissue samples and for application ex vivo. Described here is a detailed step-by-step protocol, using microplate-based fluorescence technology, to directly measure oxygen consumption rate (OCR) as an indicator of mitochondrial respiration, as well as extracellular acidification rate (ECAR) as an indicator of glycolysis, in intact ex vivo retinal tissue. This method has been used to successfully assess metabolic activities in adult mouse retina and demonstrate its application in investigating cellular mechanisms of aging and disease.

Determination of Mitochondrial Respiration and Glycolysis in Ex Vivo Retinal Tissue Samples

Described here is a detailed protocol for performing mitochondrial stress assay and glycolytic rate assay in ex vivo retinal tissue samples using a commercial bioanalyzer.

전 비보 망막 조직 샘플에서 미토콘드리아 호흡 및 글리코리시스의 결정

Mitochondrial respiration is a critical energy-generating pathway in all cells, especially retinal photoreceptors that possess a highly active metabolism. ...

신경과학

Measurement and Analysis of Extracellular Acid Production to Determine Glycolytic Rate

Extracellular measurement of oxygen consumption and acid production is a simple and powerful way to monitor rates of respiration and glycolysis1. Both mitochondrial (respiration) and non-mitochondrial (other redox) reactions consume oxygen, but these reactions can be easily distinguished by chemical inhibition of mitochondrial respiration. However, while mitochondrial oxygen consumption is an unambiguous and direct measurement of respiration rate2, the same is not true for extracellular acid production and its relationship to glycolytic rate 3-6. Extracellular acid produced by cells is derived from both lactate, produced by anaerobic glycolysis, and CO2, produced in the citric acid cycle during respiration. For glycolysis, the conversion of glucose to lactate- + H+ and the export of products into the assay medium is the source of glycolytic acidification. For respiration, the export of CO2, hydration to H2CO3 and dissociation to HCO3- + H+ is the source of respiratory acidification. The proportions of glycolytic and respiratory acidification depend on the experimental conditions, including cell type and substrate(s) provided, and can range from nearly 100% glycolytic acidification to nearly 100% respiratory acidification 6. Here, we demonstrate the data collection and calculation methods needed to determine respiratory and glycolytic contributions to total extracellular acidification by whole cells in culture using C2C12 myoblast cells as a model.

Glycolysis is a defining metabolic marker in multiple biological systems. Monitoring glycolysis by measuring the extracellular flux of H+ is common, but requires correction to be quantitative and unambiguous. Here, we demonstrate how to gather and correct extracellular flux data to distinguish between respiratory and glycolytic sources of extracellular acidification.

세포 외 산 생산의 측정 및 분석은 당분 속도를 확인하는

Extracellular measurement of oxygen consumption and acid production is a simple and powerful way to monitor rates of respiration and glycolysis1. Both ...

생물학

Development of a Mobile Mitochondrial Physiology Laboratory for Measuring Mitochondrial Energetics in the Field

Mitochondrial energetics is a central theme in animal biochemistry and physiology, with researchers using mitochondrial respiration as a metric to investigate metabolic capability. To obtain the measures of mitochondrial respiration, fresh biological samples must be used, and the entire laboratory procedure must be completed within approximately 2 h. Furthermore, multiple pieces of specialized equipment are required to perform these laboratory assays. This creates a challenge for measuring mitochondrial respiration in the tissues of wild animals living far from physiology laboratories as live tissue cannot be preserved for very long after collection in the field. Moreover, transporting live animals over long distances induces stress, which can alter mitochondrial energetics.
This manuscript introduces the Auburn University (AU) MitoMobile, a mobile mitochondrial physiology laboratory that can be taken into the field and used on-site to measure mitochondrial metabolism in tissues collected from wild animals. The basic features of the mobile laboratory and the step-by-step methods for measuring isolated mitochondrial respiration rates are presented. Additionally, the data presented validate the success of outfitting the mobile mitochondrial physiology laboratory and making mitochondrial respiration measurements. The novelty of the mobile laboratory lies in the ability to drive to the field and perform mitochondrial measurements on the tissues of animals captured on site.

We designed and constructed a mobile laboratory to measure respiration rates in isolated mitochondria of wild animals captured at field locations. Here, we describe the design and outfitting of a mobile mitochondrial laboratory and the associated laboratory protocols.

현장에서 미토콘드리아 에너지를 측정하기 위한 이동식 미토콘드리아 생리학 실험실 개발

Mitochondrial energetics is a central theme in animal biochemistry and physiology, with researchers using mitochondrial respiration as a metric to ...

Measuring the Rate of Lipolysis in Ex Vivo Murine Adipose Tissue and Primary Preadipocytes Differentiated In Vitro

Adipocytes store energy in the form of triglycerides in lipid droplets. This energy can be mobilized via lipolysis, where the fatty acid side chains are sequentially cleaved from the glycerol backbone, resulting in the release of free fatty acids and glycerol. Due to the low expression of glycerol kinase in white adipocytes, glycerol re-uptake rates are negligible, while fatty acid re-uptake is dictated by the fatty acid binding capacity of media components such as albumin. Both glycerol and fatty acid release into media can be quantified by colorimetric assays to determine the lipolytic rate. By measuring these factors at multiple time points, one can determine the linear rate of lipolysis with high confidence. Here, we provide a detailed protocol for the measurement of lipolysis in in vitro differentiated adipocytes and ex vivo adipose tissue from mice. This protocol may also be optimized for other preadipocyte cell lines or adipose tissue from other organisms; considerations and optimization parameters are discussed. This protocol is designed to be useful in determining and comparing the rate of adipocyte lipolysis between mouse models and treatments.