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Harrison LM, Brisard BM, Cashwell KD, Mulkey AL, Schmidt CA. "A Low-Cost Microfluidics System for Light Microscopy Experiments". bioRxiv 2024:2024.04.29.591694. [PMID: 38746427 PMCID: PMC11092470 DOI: 10.1101/2024.04.29.591694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Microfluidics devices are powerful tools for studying dynamic processes in live cells, especially when used in conjunction with light microscopy. There are many applications of microfluidics devices including recording dynamic cellular responses to small molecules or other chemical conditions in perfused media, monitoring cell migration in constrained spaces, or collecting media perfusate for the study of secreted compounds in response to experimental inputs/manipulations. Here we describe a configurable low-cost (channel-based) microfluidics platform for live-cell microscopy, intended to be useful for experiments that require more precision/flexibility than simple rubber spacers, but less precision than molded elastomer-based platforms. The materials are widely commercially available, low-cost, and device assembly takes only minutes.
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2
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Hagen JT, Montgomery MM, Aruleba RT, Chrest BR, Green TD, Kassai M, Zeczycki TN, Schmidt CA, Bhowmick D, Tan SF, Feith DJ, Chalfant CE, Loughran TP, Liles D, Minden MD, Schimmer AD, Cabot MC, Mclung JM, Fisher-Wellman KH. Mitochondria inside acute myeloid leukemia cells hydrolyze ATP to resist chemotherapy. bioRxiv 2024:2024.04.12.589110. [PMID: 38659944 PMCID: PMC11042215 DOI: 10.1101/2024.04.12.589110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Despite early optimism, therapeutics targeting oxidative phosphorylation (OxPhos) have faced clinical setbacks, stemming from their inability to distinguish healthy from cancerous mitochondria. Herein, we describe an actionable bioenergetic mechanism unique to cancerous mitochondria inside acute myeloid leukemia (AML) cells. Unlike healthy cells which couple respiration to the synthesis of ATP, AML mitochondria were discovered to support inner membrane polarization by consuming ATP. Because matrix ATP consumption allows cells to survive bioenergetic stress, we hypothesized that AML cells may resist cell death induced by OxPhos damaging chemotherapy by reversing the ATP synthase reaction. In support of this, targeted inhibition of BCL-2 with venetoclax abolished OxPhos flux without impacting mitochondrial membrane potential. In surviving AML cells, sustained polarization of the mitochondrial inner membrane was dependent on matrix ATP consumption. Mitochondrial ATP consumption was further enhanced in AML cells made refractory to venetoclax, consequential to downregulations in both the proton-pumping respiratory complexes, as well as the endogenous F1-ATPase inhibitor ATP5IF1. In treatment-naive AML, ATP5IF1 knockdown was sufficient to drive venetoclax resistance, while ATP5IF1 overexpression impaired F1-ATPase activity and heightened sensitivity to venetoclax. Collectively, our data identify matrix ATP consumption as a cancer-cell intrinsic bioenergetic vulnerability actionable in the context of mitochondrial damaging chemotherapy.
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Affiliation(s)
- James T Hagen
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC
| | - Mclane M Montgomery
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC
| | - Raphael T Aruleba
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC
| | - Brett R Chrest
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC
| | - Thomas D Green
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC
| | - Miki Kassai
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC
- Department of Biochemistry and Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, NC
| | - Tonya N Zeczycki
- Department of Biochemistry and Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, NC
| | - Cameron A Schmidt
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC
- Department of Biology, East Carolina University, Greenville, NC
| | - Debajit Bhowmick
- Flow Cytometry Core Facility, Brody School of Medicine at East Carolina University, Greenville, NC
| | - Su-Fern Tan
- Department of Medicine, Hematology/Oncology, University of Virginia School of Medicine, Charlottesville, VA
- University of Virginia Cancer Center, Charlottesville, VA
| | - David J Feith
- Department of Medicine, Hematology/Oncology, University of Virginia School of Medicine, Charlottesville, VA
- University of Virginia Cancer Center, Charlottesville, VA
| | - Charles E Chalfant
- Department of Medicine, Hematology/Oncology, University of Virginia School of Medicine, Charlottesville, VA
- University of Virginia Cancer Center, Charlottesville, VA
- Department of Cell Biology, University of Virginia, Charlottesville, VA
- Research Service, Richmond Veterans Administration Medical Center, Richmond, VA
| | - Thomas P Loughran
- Department of Medicine, Hematology/Oncology, University of Virginia School of Medicine, Charlottesville, VA
- University of Virginia Cancer Center, Charlottesville, VA
| | - Darla Liles
- Department of Internal Medicine, Brody School of Medicine, East Carolina University, Greenville, NC
| | - Mark D Minden
- Princess Margaret Cancer Centre, University Health Network, Toronto, Canada
| | - Aaron D Schimmer
- Princess Margaret Cancer Centre, University Health Network, Toronto, Canada
| | - Myles C Cabot
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC
- Department of Biochemistry and Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, NC
| | - Joseph M Mclung
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC
- Department of Cardiovascular Sciences, Brody School of Medicine, East Carolina University, Greenville, NC
| | - Kelsey H Fisher-Wellman
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC
- UNC Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC
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3
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Schmidt CA, Hale BJ, Bhowmick D, Miller WJ, Neufer PD, Geyer CB. Pyruvate modulation of redox potential controls mouse sperm motility. Dev Cell 2024; 59:79-90.e6. [PMID: 38101411 PMCID: PMC10872278 DOI: 10.1016/j.devcel.2023.11.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 06/21/2023] [Accepted: 11/13/2023] [Indexed: 12/17/2023]
Abstract
Sperm gain fertilization competence in the female reproductive tract through a series of biochemical changes and a requisite switch from linear progressive to hyperactive motility. Despite being essential for fertilization, regulation of sperm energy transduction is poorly understood. This knowledge gap confounds interpretation of interspecies variation and limits progress in optimizing sperm selection for assisted reproduction. Here, we developed a model of mouse sperm bioenergetics using metabolic phenotyping data, quantitative microscopy, and spectral flow cytometry. The results define a mechanism of motility regulation by microenvironmental pyruvate. Rather than being consumed as a mitochondrial fuel source, pyruvate stimulates hyperactivation by repressing lactate oxidation and activating glycolysis in the flagellum through provision of nicotinamide adenine dinucleotide (NAD)+. These findings provide evidence that the transitions in motility requisite for sperm competence are governed by changes in the metabolic microenvironment, highlighting the unexplored potential of using catabolite combination to optimize sperm selection for fertilization.
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Affiliation(s)
- Cameron A Schmidt
- Department of Biology at East Carolina University, Greenville, NC 27858, USA; East Carolina Diabetes and Obesity Institute at East Carolina University, Greenville, NC 27834, USA.
| | - Benjamin J Hale
- East Carolina Diabetes and Obesity Institute at East Carolina University, Greenville, NC 27834, USA; Department of Anatomy and Cell Biology, Brody School of Medicine at East Carolina University, Greenville, NC 27834, USA
| | - Debajit Bhowmick
- Flow Cytometry Core Facility, Brody School of Medicine at East Carolina University, Greenville, NC 27834, USA
| | - William J Miller
- Department of Engineering, East Carolina University, Greenville, NC 27834, USA
| | - P Darrell Neufer
- East Carolina Diabetes and Obesity Institute at East Carolina University, Greenville, NC 27834, USA; Department of Physiology, Brody School of Medicine at East Carolina University, Greenville, NC 27834, USA
| | - Christopher B Geyer
- East Carolina Diabetes and Obesity Institute at East Carolina University, Greenville, NC 27834, USA; Department of Anatomy and Cell Biology, Brody School of Medicine at East Carolina University, Greenville, NC 27834, USA.
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Abbas H, Olivere LA, Padgett ME, Schmidt CA, Gilmore BF, McCord TJ, Southerland KW, McClung JM, Kontos CD. Muscle progenitor cells are required for skeletal muscle regeneration and prevention of adipogenesis after limb ischemia. Front Cardiovasc Med 2023; 10:1118738. [PMID: 36937923 PMCID: PMC10017542 DOI: 10.3389/fcvm.2023.1118738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 02/08/2023] [Indexed: 03/06/2023] Open
Abstract
Skeletal muscle injury in peripheral artery disease (PAD) has been attributed to vascular insufficiency, however evidence has demonstrated that muscle cell responses play a role in determining outcomes in limb ischemia. Here, we demonstrate that genetic ablation of Pax7+ muscle progenitor cells (MPCs) in a model of hindlimb ischemia (HLI) inhibited muscle regeneration following ischemic injury, despite a lack of morphological or physiological changes in resting muscle. Compared to control mice (Pax7WT), the ischemic limb of Pax7-deficient mice (Pax7Δ) was unable to generate significant force 7 or 28 days after HLI. A significant increase in adipose was observed in the ischemic limb 28 days after HLI in Pax7Δ mice, which replaced functional muscle. Adipogenesis in Pax7Δ mice corresponded with a significant increase in PDGFRα+ fibro/adipogenic progenitors (FAPs). Inhibition of FAPs with batimastat decreased muscle adipose but increased fibrosis. In vitro, Pax7Δ MPCs failed to form myotubes but displayed increased adipogenesis. Skeletal muscle from patients with critical limb threatening ischemia displayed increased adipose in more ischemic regions of muscle, which corresponded with fewer satellite cells. Collectively, these data demonstrate that Pax7+ MPCs are required for muscle regeneration after ischemia and suggest that muscle regeneration may be an important therapeutic target in PAD.
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Affiliation(s)
- Hasan Abbas
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC, United States
- Duke-NUS Medical School, Singapore, Singapore
- Department of Medicine, Division of Cardiology, Duke University Medical Center, Durham, NC, United States
| | | | - Michael E. Padgett
- Department of Medicine, Division of Cardiology, Duke University Medical Center, Durham, NC, United States
| | - Cameron A. Schmidt
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC, United States
- Brody School of Medicine, East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States
| | - Brian F. Gilmore
- Department of Surgery, Duke University Medical Center, Durham, NC, United States
| | - Timothy J. McCord
- Department of Cell Biology, Duke University School of Medicine, Durham, NC, United States
| | - Kevin W. Southerland
- Department of Surgery, Duke University Medical Center, Durham, NC, United States
| | - Joseph M. McClung
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC, United States
- Brody School of Medicine, East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States
- Brody School of Medicine, East Carolina Heart Institute, East Carolina University, Greenville, NC, United States
| | - Christopher D. Kontos
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC, United States
- Department of Medicine, Division of Cardiology, Duke University Medical Center, Durham, NC, United States
- Duke University School of Medicine, Durham, NC, United States
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5
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Matthews CEP, Fussner LA, Yaeger M, Aloor JJ, Reece SW, Kilburg-Basnyat BJ, Varikuti S, Luo B, Inks M, Sergin S, Schmidt CA, Neufer PD, Pennington ER, Fisher-Wellman KH, Chowdhury SM, Fessler MB, Fenton JI, Anderson EJ, Shaikh SR, Gowdy KM. The prohibitin complex regulates macrophage fatty acid composition, plasma membrane packing, and lipid raft-mediated inflammatory signaling. Prostaglandins Leukot Essent Fatty Acids 2023; 190:102540. [PMID: 36706677 PMCID: PMC9992117 DOI: 10.1016/j.plefa.2023.102540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 12/28/2022] [Accepted: 01/15/2023] [Indexed: 01/20/2023]
Abstract
Prohibitins (PHB1 and PHB2) are ubiquitously expressed proteins which play critical roles in multiple biological processes, and together form the ring-like PHB complex found in phospholipid-rich cellular compartments including lipid rafts. Recent studies have implicated PHB1 as a mediator of fatty acid transport as well as a membrane scaffold mediating B lymphocyte and mast cell signal transduction. However, the specific role of PHBs in the macrophage have not been characterized, including their role in fatty acid uptake and lipid raft-mediated inflammatory signaling. We hypothesized that the PHB complex regulates macrophage inflammatory signaling through the formation of lipid rafts. To evaluate our hypothesis, RAW 264.7 macrophages were transduced with shRNA against PHB1, PHB2, or scrambled control (Scr), and then stimulated with lipopolysaccharide (LPS) or tumor necrosis factor-alpha (TNF-α), which activate lipid raft-dependent receptor signaling (CD14/TLR4 and TNFR1, respectively). PHB1 knockdown was lethal, whereas PHB2 knockdown (PHB2kd), which also resulted in decreased PHB1 expression, led to attenuated nuclear factor-kappa-B (NF-κB) activation and subsequent cytokine and chemokine production. PHB2kd macrophages also had decreased cell surface TNFR1, CD14, TLR4, and lipid raft marker ganglioside GM1 at baseline and post-stimuli. Post-LPS, PHB2kd macrophages did not increase the concentration of cellular saturated, monounsaturated, and polyunsaturated fatty acids. This was accompanied by decreased lipid raft formation and modified plasma membrane molecular packing, further supporting the PHB complex's importance in lipid raft formation. Taken together, these data suggest a critical role for PHBs in regulating macrophage inflammatory signaling via maintenance of fatty acid composition and lipid raft structure. SUMMARY: Prohibitins are proteins found in phospholipid-rich cellular compartments, including lipid rafts, that play important roles in signaling, transcription, and multiple other cell functions. Macrophages are key cells in the innate immune response and the presence of membrane lipid rafts is integral to signal transduction, but the role of prohibitins in macrophage lipid rafts and associated signaling is unknown. To address this question, prohibitin knockdown macrophages were generated and responses to lipopolysaccharide and tumor necrosis factor-alpha, which act through lipid raft-dependent receptors, were analyzed. Prohibitin knockdown macrophages had significantly decreased cytokine and chemokine production, transcription factor activation, receptor expression, lipid raft assembly and membrane packing, and altered fatty acid remodeling. These data indicate a novel role for prohibitins in macrophage inflammatory signaling through regulation of fatty acid composition and lipid raft formation.
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Affiliation(s)
- Christine E Psaltis Matthews
- Department of Pharmacology and Toxicology, Brody School of Medicine, East Carolina University, Greenville, NC, United States
| | - Lynn A Fussner
- Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Internal Medicine, The Ohio State University, Columbus, OH, United States
| | - Michael Yaeger
- Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Internal Medicine, The Ohio State University, Columbus, OH, United States
| | - Jim J Aloor
- Diabetes and Obesity Institute, Department of Physiology, East Carolina University, Greenville, NC, United States
| | - Sky W Reece
- Department of Pharmacology and Toxicology, Brody School of Medicine, East Carolina University, Greenville, NC, United States
| | - Brita J Kilburg-Basnyat
- Department of Pharmacology and Toxicology, Brody School of Medicine, East Carolina University, Greenville, NC, United States
| | - Sanjay Varikuti
- Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Internal Medicine, The Ohio State University, Columbus, OH, United States
| | - Bin Luo
- Department of Pharmacology and Toxicology, Brody School of Medicine, East Carolina University, Greenville, NC, United States
| | - Morgan Inks
- Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Internal Medicine, The Ohio State University, Columbus, OH, United States
| | - Selin Sergin
- Department of Food Science and Human Nutrition, Michigan State University, East Lansing, MI, United States
| | - Cameron A Schmidt
- Diabetes and Obesity Institute, Department of Physiology, East Carolina University, Greenville, NC, United States
| | - P Darrell Neufer
- Diabetes and Obesity Institute, Department of Physiology, East Carolina University, Greenville, NC, United States
| | - Edward Ross Pennington
- Department of Nutrition, Gillings School of Global Public Health and School of Medicine, University of North Carolina, Chapel Hill, NC, United States
| | - Kelsey H Fisher-Wellman
- Diabetes and Obesity Institute, Department of Physiology, East Carolina University, Greenville, NC, United States
| | - Saiful M Chowdhury
- Department of Chemistry and Biochemistry, University of Texas at Arlington, Arlington, TX, United States
| | - Michael B Fessler
- Immunity, Inflammation and Disease Laboratory, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, NC, United States
| | - Jenifer I Fenton
- Department of Food Science and Human Nutrition, Michigan State University, East Lansing, MI, United States
| | - Ethan J Anderson
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, FOE Diabetes Research Center, University of Iowa, Iowa City, IA, United States
| | - Saame Raza Shaikh
- Department of Nutrition, Gillings School of Global Public Health and School of Medicine, University of North Carolina, Chapel Hill, NC, United States
| | - Kymberly M Gowdy
- Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Internal Medicine, The Ohio State University, Columbus, OH, United States.
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Amorese AJ, Minchew EC, Tarpey MD, Readyoff AT, Williamson NC, Schmidt CA, McMillin SL, Goldberg EJ, Terwilliger ZS, Spangenburg QA, Witczak CA, Brault JJ, Abel ED, McClung JM, Fisher-Wellman KH, Spangenburg EE. Hypoxia Resistance Is an Inherent Phenotype of the Mouse Flexor Digitorum Brevis Skeletal Muscle. Function (Oxf) 2023; 4:zqad012. [PMID: 37168496 PMCID: PMC10165545 DOI: 10.1093/function/zqad012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 03/10/2023] [Accepted: 03/13/2023] [Indexed: 05/13/2023] Open
Abstract
The various functions of skeletal muscle (movement, respiration, thermogenesis, etc.) require the presence of oxygen (O2). Inadequate O2 bioavailability (ie, hypoxia) is detrimental to muscle function and, in chronic cases, can result in muscle wasting. Current therapeutic interventions have proven largely ineffective to rescue skeletal muscle from hypoxic damage. However, our lab has identified a mammalian skeletal muscle that maintains proper physiological function in an environment depleted of O2. Using mouse models of in vivo hindlimb ischemia and ex vivo anoxia exposure, we observed the preservation of force production in the flexor digitorum brevis (FDB), while in contrast the extensor digitorum longus (EDL) and soleus muscles suffered loss of force output. Unlike other muscles, we found that the FDB phenotype is not dependent on mitochondria, which partially explains the hypoxia resistance. Muscle proteomes were interrogated using a discovery-based approach, which identified significantly greater expression of the transmembrane glucose transporter GLUT1 in the FDB as compared to the EDL and soleus. Through loss-and-gain-of-function approaches, we determined that GLUT1 is necessary for the FDB to survive hypoxia, but overexpression of GLUT1 was insufficient to rescue other skeletal muscles from hypoxic damage. Collectively, the data demonstrate that the FDB is uniquely resistant to hypoxic insults. Defining the mechanisms that explain the phenotype may provide insight towards developing approaches for preventing hypoxia-induced tissue damage.
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Affiliation(s)
| | | | - Michael D Tarpey
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| | - Andrew T Readyoff
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC 27834, USA
| | - Nicholas C Williamson
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| | - Cameron A Schmidt
- Department of Biology, East Carolina University, Greenville, NC 27834, USA
| | - Shawna L McMillin
- Department of Kinesiology, East Carolina University, Greenville, NC 27858, USA
| | - Emma J Goldberg
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| | - Zoe S Terwilliger
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| | - Quincy A Spangenburg
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| | - Carol A Witczak
- Department of Anatomy, Cell Biology, and Physiology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Indiana Center for Musculoskeletal Health, Indianapolis, IN 46202, USA
- Indiana Center for Diabetes and Metabolic Diseases, Indianapolis, IN 46202, USA
| | - Jeffrey J Brault
- Department of Anatomy, Cell Biology, and Physiology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Indiana Center for Musculoskeletal Health, Indianapolis, IN 46202, USA
| | - E Dale Abel
- David Geffen School of Medicine, Department of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Joseph M McClung
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
- Department of Cardiovascular Sciences, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC 27834, USA
| | - Kelsey H Fisher-Wellman
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
- Department of Cardiovascular Sciences, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
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7
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Tang Y, Zong H, Kwon H, Qiu Y, Pessin JB, Wu L, Buddo KA, Boykov I, Schmidt CA, Lin CT, Neufer PD, Schwartz GJ, Kurland IJ, Pessin J. TIGAR deficiency enhances skeletal muscle thermogenesis by increasing neuromuscular junction cholinergic signaling. eLife 2022; 11:73360. [PMID: 35254259 PMCID: PMC8947760 DOI: 10.7554/elife.73360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 03/02/2022] [Indexed: 12/03/2022] Open
Abstract
Cholinergic and sympathetic counter-regulatory networks control numerous physiological functions, including learning/memory/cognition, stress responsiveness, blood pressure, heart rate, and energy balance. As neurons primarily utilize glucose as their primary metabolic energy source, we generated mice with increased glycolysis in cholinergic neurons by specific deletion of the fructose-2,6-phosphatase protein TIGAR. Steady-state and stable isotope flux analyses demonstrated increased rates of glycolysis, acetyl-CoA production, acetylcholine levels, and density of neuromuscular synaptic junction clusters with enhanced acetylcholine release. The increase in cholinergic signaling reduced blood pressure and heart rate with a remarkable resistance to cold-induced hypothermia. These data directly demonstrate that increased cholinergic signaling through the modulation of glycolysis has several metabolic benefits particularly to increase energy expenditure and heat production upon cold exposure.
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Affiliation(s)
- Yan Tang
- Department of Medicine, Albert Einstein College of Medicine, Bronx, United States
| | - Haihong Zong
- Department of Medicine, Albert Einstein College of Medicine, Bronx, United States
| | - Hyokjoon Kwon
- Department of Medicine, Albert Einstein College of Medicine, Bronx, United States
| | - Yunping Qiu
- Department of Medicine, Albert Einstein College of Medicine, Bronx, United States
| | - Jacob B Pessin
- Department of Medicine, Albert Einstein College of Medicine, Bronx, United States
| | - Licheng Wu
- Department of Medicine, Albert Einstein College of Medicine, Bronx, United States
| | - Katherine A Buddo
- Department of Physiology, East Carolina University, Greenville, United States
| | - Ilya Boykov
- Department of Physiology, East Carolina University, Greenville, United States
| | - Cameron A Schmidt
- Department of Physiology, East Carolina University, Greenville, United States
| | - Chien-Te Lin
- Department of Physiology, East Carolina University, Greenville, United States
| | - P Darrell Neufer
- Department of Physiology, East Carolina University, Greenville, United States
| | - Gary J Schwartz
- Department of Medicine, Albert Einstein College of Medicine, Bronx, United States
| | - Irwin J Kurland
- Department of Medicine, Albert Einstein College of Medicine, Bronx, United States
| | - Jeffrey Pessin
- Department of Medicine, Albert Einstein College of Medicine, Bronx, United States
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8
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Schmidt CA, Fisher-Wellman KH, Neufer PD. From OCR and ECAR to energy: Perspectives on the design and interpretation of bioenergetics studies. J Biol Chem 2021; 297:101140. [PMID: 34461088 PMCID: PMC8479256 DOI: 10.1016/j.jbc.2021.101140] [Citation(s) in RCA: 60] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 08/25/2021] [Accepted: 08/26/2021] [Indexed: 12/12/2022] Open
Abstract
Biological energy transduction underlies all physiological phenomena in cells. The metabolic systems that support energy transduction have been of great interest due to their association with numerous pathologies including diabetes, cancer, rare genetic diseases, and aberrant cell death. Commercially available bioenergetics technologies (e.g., extracellular flux analysis, high-resolution respirometry, fluorescent dye kits, etc.) have made practical assessment of metabolic parameters widely accessible. This has facilitated an explosion in the number of studies exploring, in particular, the biological implications of oxygen consumption rate (OCR) and substrate level phosphorylation via glycolysis (i.e., via extracellular acidification rate (ECAR)). Though these technologies have demonstrated substantial utility and broad applicability to cell biology research, they are also susceptible to historical assumptions, experimental limitations, and other caveats that have led to premature and/or erroneous interpretations. This review enumerates various important considerations for designing and interpreting cellular and mitochondrial bioenergetics experiments, some common challenges and pitfalls in data interpretation, and some potential "next steps" to be taken that can address these highlighted challenges.
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Affiliation(s)
- Cameron A Schmidt
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina, USA; Departments of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
| | - Kelsey H Fisher-Wellman
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina, USA; Departments of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA.
| | - P Darrell Neufer
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina, USA; Departments of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA; Departments of Biochemistry and Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA.
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9
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Smith CD, Lin CT, McMillin SL, Weyrauch LA, Schmidt CA, Smith CA, Kurland IJ, Witczak CA, Neufer PD. Genetically increasing flux through β-oxidation in skeletal muscle increases mitochondrial reductive stress and glucose intolerance. Am J Physiol Endocrinol Metab 2021; 320:E938-E950. [PMID: 33813880 PMCID: PMC8238127 DOI: 10.1152/ajpendo.00010.2021] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Elevated mitochondrial hydrogen peroxide (H2O2) emission and an oxidative shift in cytosolic redox environment have been linked to high-fat-diet-induced insulin resistance in skeletal muscle. To test specifically whether increased flux through mitochondrial fatty acid oxidation, in the absence of elevated energy demand, directly alters mitochondrial function and redox state in muscle, two genetic models characterized by increased muscle β-oxidation flux were studied. In mice overexpressing peroxisome proliferator-activated receptor-α in muscle (MCK-PPARα), lipid-supported mitochondrial respiration, membrane potential (ΔΨm), and H2O2 production rate (JH2O2) were increased, which coincided with a more oxidized cytosolic redox environment, reduced muscle glucose uptake, and whole body glucose intolerance despite an increased rate of energy expenditure. Similar results were observed in lipin-1-deficient, fatty-liver dystrophic mice, another model characterized by increased β-oxidation flux and glucose intolerance. Crossing MCAT (mitochondria-targeted catalase) with MCK-PPARα mice normalized JH2O2 production, redox environment, and glucose tolerance, but surprisingly, both basal and absolute insulin-stimulated rates of glucose uptake in muscle remained depressed. Also surprising, when placed on a high-fat diet, MCK-PPARα mice were characterized by much lower whole body, fat, and lean mass as well as improved glucose tolerance relative to wild-type mice, providing additional evidence that overexpression of PPARα in muscle imposes more extensive metabolic stress than experienced by wild-type mice on a high-fat diet. Overall, the findings suggest that driving an increase in skeletal muscle fatty acid oxidation in the absence of metabolic demand imposes mitochondrial reductive stress and elicits multiple counterbalance metabolic responses in an attempt to restore bioenergetic homeostasis.NEW & NOTEWORTHY Prior work has suggested that mitochondrial dysfunction is an underlying cause of insulin resistance in muscle because it limits fatty acid oxidation and therefore leads to the accumulation of cytotoxic lipid intermediates. The implication has been that therapeutic strategies to accelerate β-oxidation will be protective. The current study provides evidence that genetically increasing flux through β-oxidation in muscle imposes reductive stress that is not beneficial but rather detrimental to metabolic regulation.
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Affiliation(s)
- Cody D Smith
- East Carolina Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University, Greenville, North Carolina
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina
| | - Chien-Te Lin
- East Carolina Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University, Greenville, North Carolina
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina
| | - Shawna L McMillin
- East Carolina Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University, Greenville, North Carolina
- Department of Biochemistry & Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, North Carolina
| | - Luke A Weyrauch
- East Carolina Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University, Greenville, North Carolina
- Department of Biochemistry & Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, North Carolina
| | - Cameron A Schmidt
- East Carolina Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University, Greenville, North Carolina
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina
| | - Cheryl A Smith
- East Carolina Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University, Greenville, North Carolina
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina
| | - Irwin J Kurland
- Department of Medicine, Albert Einstein College of Medicine, Bronx, New York
| | - Carol A Witczak
- East Carolina Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University, Greenville, North Carolina
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina
- Department of Biochemistry & Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, North Carolina
- Department of Kinesiology, East Carolina University, Greenville, North Carolina
| | - P Darrell Neufer
- East Carolina Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University, Greenville, North Carolina
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina
- Department of Biochemistry & Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, North Carolina
- Department of Kinesiology, East Carolina University, Greenville, North Carolina
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10
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Smith CD, Schmidt CA, Fisher-Wellman KH, Neufer PD. Reply to Figueira et al.: Can NAD(P) + transhydrogenase (NNT) mediate a physiologically meaningful increase in energy expenditure by mitochondria during H 2O 2 removal? J Biol Chem 2021; 296:100378. [PMID: 33837732 PMCID: PMC7988312 DOI: 10.1016/j.jbc.2021.100378] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 02/02/2021] [Indexed: 11/28/2022] Open
Affiliation(s)
- Cody D Smith
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina, USA; Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
| | - Cameron A Schmidt
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina, USA; Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
| | - Kelsey H Fisher-Wellman
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina, USA; Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
| | - P Darrell Neufer
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina, USA; Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA.
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11
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Terwilliger ZS, Ryan TE, Goldberg EJ, Schmidt CA, Yamaguchi DJ, Karnekar R, Brophy P, Green TD, Zeczycki TN, Mac Gabhann F, Annex BH, McClung JM. Racial differences in the limb skeletal muscle transcriptional programs of patients with critical limb ischemia. Vasc Med 2021; 26:247-258. [PMID: 33685287 DOI: 10.1177/1358863x20983918] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Critical limb ischemia (CLI) is the most severe manifestation of peripheral artery disease (PAD) and is characterized by high rates of morbidity and mortality. As with most severe cardiovascular disease manifestations, Black individuals disproportionately present with CLI. Accordingly, there remains a clear need to better understand the reasons for this discrepancy and to facilitate personalized therapeutic options specific for this population. Gastrocnemius muscle was obtained from White and Black healthy adult volunteers and patients with CLI for whole transcriptome shotgun sequencing (WTSS) and enrichment analysis was performed to identify alterations in specific Reactome pathways. When compared to their race-matched healthy controls, both White and Black patients with CLI demonstrated similar reductions in nuclear and mitochondrial encoded genes and mitochondrial oxygen consumption across multiple substrates, indicating a common bioenergetic paradigm associated with amputation outcomes regardless of race. Direct comparisons between tissues of White and Black patients with CLI revealed hemostasis, extracellular matrix organization, platelet regulation, and vascular wall interactions to be uniquely altered in limb muscles of Black individuals. Among traditional vascular growth factor signaling targets, WTSS revealed only Tie1 to be significantly altered from White levels in Black limb muscle tissues. Quantitative reverse transcription polymerase chain reaction validation of select identified targets verified WTSS directional changes and supports reductions in MMP9 and increases in NUDT4P1 and GRIK2 as unique to limb muscles of Black patients with CLI. This represents a critical first step in better understanding the transcriptional program similarities and differences between Black and White patients in the setting of amputations related to CLI and provides a promising start for therapeutic development in this population.
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Affiliation(s)
- Zoe S Terwilliger
- Diabetes and Obesity Institute, East Carolina University, Brody Medical Center, Greenville, NC, USA.,Department of Physiology, East Carolina University, Brody Medical Center, Greenville, NC, USA
| | - Terence E Ryan
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA
| | - Emma J Goldberg
- Diabetes and Obesity Institute, East Carolina University, Brody Medical Center, Greenville, NC, USA.,Department of Physiology, East Carolina University, Brody Medical Center, Greenville, NC, USA
| | - Cameron A Schmidt
- Diabetes and Obesity Institute, East Carolina University, Brody Medical Center, Greenville, NC, USA.,Department of Physiology, East Carolina University, Brody Medical Center, Greenville, NC, USA
| | - Dean J Yamaguchi
- Department of Cardiovascular Sciences, East Carolina University, Brody Medical Center, Greenville, NC, USA.,Division of Surgery, East Carolina University, Brody Medical Center, Greenville, NC, USA
| | - Reema Karnekar
- Diabetes and Obesity Institute, East Carolina University, Brody Medical Center, Greenville, NC, USA.,Department of Physiology, East Carolina University, Brody Medical Center, Greenville, NC, USA
| | - Patricia Brophy
- Diabetes and Obesity Institute, East Carolina University, Brody Medical Center, Greenville, NC, USA
| | - Thomas D Green
- Diabetes and Obesity Institute, East Carolina University, Brody Medical Center, Greenville, NC, USA.,Department of Physiology, East Carolina University, Brody Medical Center, Greenville, NC, USA
| | - Tonya N Zeczycki
- Diabetes and Obesity Institute, East Carolina University, Brody Medical Center, Greenville, NC, USA.,Department of Biochemistry, East Carolina University, Brody Medical Center, Greenville, NC, USA
| | - Feilim Mac Gabhann
- Department of Biomedical Engineering and Institute for Computational Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Brian H Annex
- Department of Medicine, Medical College of Georgia, Augusta, GA, USA.,Vascular Biology Center, Medical College of Georgia, Augusta, GA, USA
| | - Joseph M McClung
- Diabetes and Obesity Institute, East Carolina University, Brody Medical Center, Greenville, NC, USA.,Department of Physiology, East Carolina University, Brody Medical Center, Greenville, NC, USA.,Department of Cardiovascular Sciences, East Carolina University, Brody Medical Center, Greenville, NC, USA
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12
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Schmidt CA, McLaughlin KL, Boykov IN, Mojalagbe R, Ranganathan A, Buddo KA, Lin CT, Fisher-Wellman KH, Neufer PD. Aglycemic growth enhances carbohydrate metabolism and induces sensitivity to menadione in cultured tumor-derived cells. Cancer Metab 2021; 9:3. [PMID: 33468237 PMCID: PMC7816515 DOI: 10.1186/s40170-021-00241-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 01/06/2021] [Indexed: 12/19/2022] Open
Abstract
Background Hepatocellular carcinoma (HCC) is the most prevalent form of liver malignancy and carries poor prognoses due to late presentation of symptoms. Treatment of late-stage HCC relies heavily on chemotherapeutics, many of which target cellular energy metabolism. A key platform for testing candidate chemotherapeutic compounds is the intrahepatic orthotopic xenograft (IOX) model in rodents. Translational efficacy from the IOX model to clinical use is limited (in part) by variation in the metabolic phenotypes of the tumor-derived cells that can be induced by selective adaptation to subculture conditions. Methods In this study, a detailed multilevel systems approach combining microscopy, respirometry, potentiometry, and extracellular flux analysis (EFA) was utilized to examine metabolic adaptations that occur under aglycemic growth media conditions in HCC-derived (HEPG2) cells. We hypothesized that aglycemic growth would result in adaptive “aerobic poise” characterized by enhanced capacity for oxidative phosphorylation over a range of physiological energetic demand states. Results Aglycemic growth did not invoke adaptive changes in mitochondrial content, network complexity, or intrinsic functional capacity/efficiency. In intact cells, aglycemic growth markedly enhanced fermentative glycolytic substrate-level phosphorylation during glucose refeeding and enhanced responsiveness of both fermentation and oxidative phosphorylation to stimulated energy demand. Additionally, aglycemic growth induced sensitivity of HEPG2 cells to the provitamin menadione at a 25-fold lower dose compared to control cells. Conclusions These findings indicate that growth media conditions have substantial effects on the energy metabolism of subcultured tumor-derived cells, which may have significant implications for chemotherapeutic sensitivity during incorporation in IOX testing panels. Additionally, the metabolic phenotyping approach used in this study provides a practical workflow that can be incorporated with IOX screening practices to aid in deciphering the metabolic underpinnings of chemotherapeutic drug sensitivity. Supplementary Information The online version contains supplementary material available at 10.1186/s40170-021-00241-0.
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Affiliation(s)
- Cameron A Schmidt
- East Carolina Diabetes and Obesity Institute, Greenville, NC, USA.,Dept. of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC, USA
| | - Kelsey L McLaughlin
- East Carolina Diabetes and Obesity Institute, Greenville, NC, USA.,Dept. of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC, USA
| | - Ilya N Boykov
- East Carolina Diabetes and Obesity Institute, Greenville, NC, USA.,Dept. of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC, USA
| | - Rafiq Mojalagbe
- East Carolina Diabetes and Obesity Institute, Greenville, NC, USA
| | | | - Katherine A Buddo
- East Carolina Diabetes and Obesity Institute, Greenville, NC, USA.,Dept. of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC, USA
| | - Chien-Te Lin
- East Carolina Diabetes and Obesity Institute, Greenville, NC, USA.,Dept. of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC, USA
| | - Kelsey H Fisher-Wellman
- East Carolina Diabetes and Obesity Institute, Greenville, NC, USA. .,Dept. of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC, USA.
| | - P Darrell Neufer
- East Carolina Diabetes and Obesity Institute, Greenville, NC, USA. .,Dept. of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC, USA.
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13
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Ryan TE, Schmidt CA, Tarpey MD, Amorese AJ, Yamaguchi DJ, Goldberg EJ, Iñigo MM, Karnekar R, O'Rourke A, Ervasti JM, Brophy P, Green TD, Neufer PD, Fisher-Wellman K, Spangenburg EE, McClung JM. PFKFB3-mediated glycolysis rescues myopathic outcomes in the ischemic limb. JCI Insight 2020; 5:139628. [PMID: 32841216 PMCID: PMC7526546 DOI: 10.1172/jci.insight.139628] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 08/19/2020] [Indexed: 12/24/2022] Open
Abstract
Compromised muscle mitochondrial metabolism is a hallmark of peripheral arterial disease, especially in patients with the most severe clinical manifestation - critical limb ischemia (CLI). We asked whether inflexibility in metabolism is critical for the development of myopathy in ischemic limb muscles. Using Polg mtDNA mutator (D257A) mice, we reveal remarkable protection from hind limb ischemia (HLI) due to a unique and beneficial adaptive enhancement of glycolytic metabolism and elevated ischemic muscle PFKFB3. Similar to the relationship between mitochondria from CLI and claudicating patient muscles, BALB/c muscle mitochondria are uniquely dysfunctional after HLI onset as compared with the C57BL/6 (BL6) parental strain. AAV-mediated overexpression of PFKFB3 in BALB/c limb muscles improved muscle contractile function and limb blood flow following HLI. Enrichment analysis of RNA sequencing data on muscle from CLI patients revealed a unique deficit in the glucose metabolism Reactome. Muscles from these patients express lower PFKFB3 protein, and their muscle progenitor cells possess decreased glycolytic flux capacity in vitro. Here, we show supplementary glycolytic flux as sufficient to protect against ischemic myopathy in instances where reduced blood flow-related mitochondrial function is compromised preclinically. Additionally, our data reveal reduced glycolytic flux as a common characteristic of the failing CLI patient limb skeletal muscle.
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Affiliation(s)
- Terence E Ryan
- East Carolina Diabetes and Obesity Institute.,Department of Physiology
| | - Cameron A Schmidt
- East Carolina Diabetes and Obesity Institute.,Department of Physiology
| | - Michael D Tarpey
- East Carolina Diabetes and Obesity Institute.,Department of Physiology
| | - Adam J Amorese
- East Carolina Diabetes and Obesity Institute.,Department of Physiology
| | - Dean J Yamaguchi
- Department of Cardiovascular Science, and.,Division of Surgery, East Carolina University, Brody School of Medicine, Greenville, North Carolina, USA
| | - Emma J Goldberg
- East Carolina Diabetes and Obesity Institute.,Department of Physiology
| | - Melissa Mr Iñigo
- East Carolina Diabetes and Obesity Institute.,Department of Physiology
| | - Reema Karnekar
- East Carolina Diabetes and Obesity Institute.,Department of Physiology
| | - Allison O'Rourke
- Department of Biochemistry, Molecular Biology and Biophysics, College of Biological Sciences, University of Minnesota, Saint Paul, Minnesota, USA
| | - James M Ervasti
- Department of Biochemistry, Molecular Biology and Biophysics, College of Biological Sciences, University of Minnesota, Saint Paul, Minnesota, USA
| | | | - Thomas D Green
- East Carolina Diabetes and Obesity Institute.,Department of Physiology
| | - P Darrell Neufer
- East Carolina Diabetes and Obesity Institute.,Department of Physiology
| | | | | | - Joseph M McClung
- East Carolina Diabetes and Obesity Institute.,Department of Physiology.,Department of Cardiovascular Science, and
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14
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Smith CD, Schmidt CA, Lin CT, Fisher-Wellman KH, Neufer PD. Flux through mitochondrial redox circuits linked to nicotinamide nucleotide transhydrogenase generates counterbalance changes in energy expenditure. J Biol Chem 2020; 295:16207-16216. [PMID: 32747443 DOI: 10.1074/jbc.ra120.013899] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Revised: 07/15/2020] [Indexed: 01/21/2023] Open
Abstract
Compensatory changes in energy expenditure occur in response to positive and negative energy balance, but the underlying mechanism remains unclear. Under low energy demand, the mitochondrial electron transport system is particularly sensitive to added energy supply (i.e. reductive stress), which exponentially increases the rate of H2O2 (JH2O2) production. H2O2 is reduced to H2O by electrons supplied by NADPH. NADP+ is reduced back to NADPH by activation of mitochondrial membrane potential-dependent nicotinamide nucleotide transhydrogenase (NNT). The coupling of reductive stress-induced JH2O2 production to NNT-linked redox buffering circuits provides a potential means of integrating energy balance with energy expenditure. To test this hypothesis, energy supply was manipulated by varying flux rate through β-oxidation in muscle mitochondria minus/plus pharmacological or genetic inhibition of redox buffering circuits. Here we show during both non-ADP- and low-ADP-stimulated respiration that accelerating flux through β-oxidation generates a corresponding increase in mitochondrial JH2O2 production, that the majority (∼70-80%) of H2O2 produced is reduced to H2O by electrons drawn from redox buffering circuits supplied by NADPH, and that the rate of electron flux through redox buffering circuits is directly linked to changes in oxygen consumption mediated by NNT. These findings provide evidence that redox reactions within β-oxidation and the electron transport system serve as a barometer of substrate flux relative to demand, continuously adjusting JH2O2 production and, in turn, the rate at which energy is expended via NNT-mediated proton conductance. This variable flux through redox circuits provides a potential compensatory mechanism for fine-tuning energy expenditure to energy balance in real time.
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Affiliation(s)
- Cody D Smith
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina, USA; Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
| | - Cameron A Schmidt
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina, USA; Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
| | - Chien-Te Lin
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina, USA; Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
| | - Kelsey H Fisher-Wellman
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina, USA; Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
| | - P Darrell Neufer
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina, USA; Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA.
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15
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Schmidt CA, Goldberg EJ, Green TD, Karnekar RR, Brault JJ, Miller SG, Amorese AJ, Yamaguchi DJ, Spangenburg EE, McClung JM. Effects of fasting on isolated murine skeletal muscle contractile function during acute hypoxia. PLoS One 2020; 15:e0225922. [PMID: 32324778 PMCID: PMC7179920 DOI: 10.1371/journal.pone.0225922] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Accepted: 04/03/2020] [Indexed: 11/19/2022] Open
Abstract
Stored muscle carbohydrate supply and energetic efficiency constrain muscle functional capacity during exercise and are influenced by common physiological variables (e.g. age, diet, and physical activity level). Whether these constraints affect overall functional capacity or the timing of muscle energetic failure during acute hypoxia is not known. We interrogated skeletal muscle contractile properties in two anatomically distinct rodent hindlimb muscles that have well characterized differences in energetic efficiency (locomotory- extensor digitorum longus (EDL) and postural- soleus muscles) following a 24 hour fasting period that resulted in substantially reduced muscle carbohydrate supply. 180 mins of acute hypoxia resulted in complete energetic failure in all muscles tested, indicated by: loss of force production, substantial reductions in total adenosine nucleotide pool intermediates, and increased adenosine nucleotide degradation product-inosine monophosphate (IMP). These changes occurred in the absence of apparent myofiber structural damage assessed histologically by both transverse section and whole mount. Fasting and the associated reduction of the available intracellular carbohydrate pool (~50% decrease in skeletal muscle) did not significantly alter the timing to muscle functional impairment or affect the overall force/work capacities of either muscle type. Fasting resulted in greater passive tension development in both muscle types, which may have implications for the design of pre-clinical studies involving optimal timing of reperfusion or administration of precision therapeutics.
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Affiliation(s)
- Cameron A. Schmidt
- Dept. of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, United States of America
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina, United States of America
| | - Emma J. Goldberg
- Dept. of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, United States of America
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina, United States of America
| | - Tom D. Green
- Dept. of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, United States of America
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina, United States of America
| | - Reema R. Karnekar
- Dept. of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, United States of America
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina, United States of America
| | - Jeffrey J. Brault
- Dept. of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, United States of America
- Dept. of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Spencer G. Miller
- Dept. of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Adam J. Amorese
- Dept. of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, United States of America
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina, United States of America
| | - Dean J. Yamaguchi
- Department of Cardiovascular Sciences, East Carolina University, Greenville, North Carolina, United States of America
- Division of Surgery, Brody School of Medicine, East Carolina University, Greenville, North Carolina, United States of America
| | - Espen E. Spangenburg
- Dept. of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, United States of America
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina, United States of America
| | - Joseph M. McClung
- Dept. of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, United States of America
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina, United States of America
- Department of Cardiovascular Sciences, East Carolina University, Greenville, North Carolina, United States of America
- * E-mail:
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16
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Iñigo MR, Amorese AJ, Tarpey MD, Balestrieri NP, Jones KG, Patteson DJ, Jackson KC, Torres MJ, Lin CT, Smith CD, Heden TD, McMillin SL, Weyrauch LA, Stanley EC, Schmidt CA, Kilburg-Basnyat BB, Reece SW, Psaltis CE, Leinwand LA, Funai K, McClung JM, Gowdy KM, Witczak CA, Lowe DA, Neufer PD, Spangenburg EE. Estrogen receptor-α in female skeletal muscle is not required for regulation of muscle insulin sensitivity and mitochondrial regulation. Mol Metab 2020; 34:1-15. [PMID: 32180550 PMCID: PMC6994285 DOI: 10.1016/j.molmet.2019.12.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 12/16/2019] [Accepted: 12/17/2019] [Indexed: 12/18/2022] Open
Abstract
OBJECTIVE Estrogen receptor-α (ERα) is a nuclear receptor family member thought to substantially contribute to the metabolic regulation of skeletal muscle. However, previous mouse models utilized to assess the necessity of ERα signaling in skeletal muscle were confounded by altered developmental programming and/or influenced by secondary effects, making it difficult to assign a causal role for ERα. The objective of this study was to determine the role of skeletal muscle ERα in regulating metabolism in the absence of confounding factors of development. METHODS A novel mouse model was developed allowing for induced deletion of ERα in adult female skeletal muscle (ERαKOism). ERαshRNA was also used to knockdown ERα (ERαKD) in human myotubes cultured from primary human skeletal muscle cells isolated from muscle biopsies from healthy and obese insulin-resistant women. RESULTS Twelve weeks of HFD exposure had no differential effects on body composition, VO2, VCO2, RER, energy expenditure, and activity counts across genotypes. Although ERαKOism mice exhibited greater glucose intolerance than wild-type (WT) mice after chronic HFD, ex vivo skeletal muscle glucose uptake was not impaired in the ERαKOism mice. Expression of pro-inflammatory genes was altered in the skeletal muscle of the ERαKOism, but the concentrations of these inflammatory markers in the systemic circulation were either lower or remained similar to the WT mice. Finally, skeletal muscle mitochondrial respiratory capacity, oxidative phosphorylation efficiency, and H2O2 emission potential was not affected in the ERαKOism mice. ERαKD in human skeletal muscle cells neither altered differentiation capacity nor caused severe deficits in mitochondrial respiratory capacity. CONCLUSIONS Collectively, these results suggest that ERα function is superfluous in protecting against HFD-induced skeletal muscle metabolic derangements after postnatal development is complete.
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Affiliation(s)
- Melissa R Iñigo
- East Carolina University Brody School of Medicine, Department of Physiology, Greenville, NC, USA
| | - Adam J Amorese
- East Carolina University Brody School of Medicine, Department of Physiology, Greenville, NC, USA
| | - Michael D Tarpey
- East Carolina University Brody School of Medicine, Department of Physiology, Greenville, NC, USA
| | - Nicholas P Balestrieri
- East Carolina University, East Carolina Diabetes and Obesity Institute, Greenville, NC, USA
| | - Keith G Jones
- East Carolina University, East Carolina Diabetes and Obesity Institute, Greenville, NC, USA
| | - Daniel J Patteson
- East Carolina University, East Carolina Diabetes and Obesity Institute, Greenville, NC, USA
| | - Kathryn C Jackson
- University of Maryland, School of Public Health, Department of Kinesiology, College Park, MD, USA
| | - Maria J Torres
- East Carolina University, Department of Kinesiology, Greenville, NC, USA
| | - Chien-Te Lin
- East Carolina University, East Carolina Diabetes and Obesity Institute, Greenville, NC, USA
| | - Cody D Smith
- East Carolina University Brody School of Medicine, Department of Physiology, Greenville, NC, USA
| | - Timothy D Heden
- East Carolina University, Department of Kinesiology, Greenville, NC, USA
| | - Shawna L McMillin
- East Carolina University, Department of Kinesiology, Greenville, NC, USA
| | - Luke A Weyrauch
- East Carolina University, Department of Kinesiology, Greenville, NC, USA
| | - Erin C Stanley
- East Carolina University, Department of Kinesiology, Greenville, NC, USA
| | - Cameron A Schmidt
- East Carolina University Brody School of Medicine, Department of Physiology, Greenville, NC, USA
| | - Brita B Kilburg-Basnyat
- East Carolina University Brody School of Medicine, Department of Pharmacology and Toxicology, Greenville, NC, USA
| | - Sky W Reece
- East Carolina University Brody School of Medicine, Department of Pharmacology and Toxicology, Greenville, NC, USA
| | - Christine E Psaltis
- East Carolina University Brody School of Medicine, Department of Pharmacology and Toxicology, Greenville, NC, USA
| | - Leslie A Leinwand
- University of Colorado, Department of Molecular, Cellular, and Developmental Biology and BioFrontiers Institute, Boulder, CO, USA
| | - Katsuhiko Funai
- East Carolina University Brody School of Medicine, Department of Physiology, Greenville, NC, USA; East Carolina University, East Carolina Diabetes and Obesity Institute, Greenville, NC, USA; East Carolina University, Department of Kinesiology, Greenville, NC, USA
| | - Joseph M McClung
- East Carolina University Brody School of Medicine, Department of Physiology, Greenville, NC, USA; East Carolina University, East Carolina Diabetes and Obesity Institute, Greenville, NC, USA
| | - Kymberly M Gowdy
- East Carolina University, East Carolina Diabetes and Obesity Institute, Greenville, NC, USA; East Carolina University Brody School of Medicine, Department of Pharmacology and Toxicology, Greenville, NC, USA
| | - Carol A Witczak
- East Carolina University Brody School of Medicine, Department of Physiology, Greenville, NC, USA; East Carolina University, East Carolina Diabetes and Obesity Institute, Greenville, NC, USA; East Carolina University, Department of Kinesiology, Greenville, NC, USA; East Carolina University, Department of Biochemistry and Molecular Biology, Greenville, NC, USA
| | - Dawn A Lowe
- University of Minnesota, Department of Rehabilitation Medicine, Division of Rehabilitation Science and Division of Physical Therapy, Minneapolis, MN, USA
| | - P Darrell Neufer
- East Carolina University Brody School of Medicine, Department of Physiology, Greenville, NC, USA; East Carolina University, East Carolina Diabetes and Obesity Institute, Greenville, NC, USA; East Carolina University, Department of Kinesiology, Greenville, NC, USA
| | - Espen E Spangenburg
- East Carolina University Brody School of Medicine, Department of Physiology, Greenville, NC, USA; East Carolina University, East Carolina Diabetes and Obesity Institute, Greenville, NC, USA; East Carolina University, Department of Kinesiology, Greenville, NC, USA.
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17
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Goldberg EJ, Schmidt CA, Green TD, Karnekar R, Yamaguchi DJ, Spangenberg EE, McClung JM. Temporal Association Between Ischemic Muscle Perfusion Recovery and the Restoration of Muscle Contractile Function After Hindlimb Ischemia. Front Physiol 2019; 10:804. [PMID: 31316393 PMCID: PMC6611152 DOI: 10.3389/fphys.2019.00804] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 06/06/2019] [Indexed: 12/15/2022] Open
Abstract
During incomplete skeletal muscle recovery from ischemia, such as that occurs with critical limb ischemia, the temporal relationship between recovery of muscle capillary perfusion and contractile function is poorly defined. We examined this relationship in BALB/cJ mice (N = 24) following unilateral hindlimb ischemia (HLI), which pre-clinically mimics the myopathy observed in critical limb ischemia patients. Specifically, we examined this relationship in two phenotypically distinct muscles (i.e., "oxidative" soleus - Sol and "glycolytic" extensor digitorum longus - EDL) 14- or 56-days after HLI. Although overall limb blood flow (LDPI) reached its' recovery peak (48% of control) by HLI d14, the capillary networks in both the Sol and EDL (whole mount confocal imaging) were disrupted and competent muscle capillary perfusion (perfused lectin+μm2/muscle μm2) remained reduced. Interestingly, both Sol and EDL muscles recovered their distinct capillary structures and perfusion (Con Sol; 0.056 ± 0.02 lectin+μm2/muscle μm2, and Con EDL; 0.039 ± 0.005 lectin+μm2/muscle μm2) by HLI d56 (Sol; 0.062 ± 0.011 lectin+μm2/muscle μm2 and EDL; 0.0035 ± 0.005 lectin+μm2/muscle μm2), despite no further improvement in limb blood flow (LDPI). Both muscles suffered severe myopathy, indicated by loss of dystrophin positive immunostaining and the absence of stimulation induced isometric force production at HLI d14. Dystrophin immunofluorescence returned at HLI d56, although neither myofiber CSA (μm2) nor isometric force production (58 and 28% sustained deficits, Sol and EDL, respectively) recovered completely in either muscle. In summary, we reveal that the temporal relationship between the restoration of muscle capillary perfusion and functional ischemic skeletal muscle regeneration favors competent muscle capillary perfusion recovery in BALB/c mice in a phenotypically non-distinct manner.
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Affiliation(s)
- Emma J Goldberg
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC, United States.,East Carolina Diabetes and Obesity Institute, East Carolina Heart Institute, Brody School of Medicine, East Carolina University, Greenville, NC, United States
| | - Cameron A Schmidt
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC, United States.,East Carolina Diabetes and Obesity Institute, East Carolina Heart Institute, Brody School of Medicine, East Carolina University, Greenville, NC, United States
| | - T D Green
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC, United States.,East Carolina Diabetes and Obesity Institute, East Carolina Heart Institute, Brody School of Medicine, East Carolina University, Greenville, NC, United States
| | - R Karnekar
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC, United States.,East Carolina Diabetes and Obesity Institute, East Carolina Heart Institute, Brody School of Medicine, East Carolina University, Greenville, NC, United States
| | - D J Yamaguchi
- Department of Cardiovascular Sciences, Brody School of Medicine, East Carolina University, Greenville, NC, United States.,Division of Surgery, Brody School of Medicine, East Carolina University, Greenville, NC, United States
| | - E E Spangenberg
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC, United States.,East Carolina Diabetes and Obesity Institute, East Carolina Heart Institute, Brody School of Medicine, East Carolina University, Greenville, NC, United States
| | - Joseph M McClung
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC, United States.,East Carolina Diabetes and Obesity Institute, East Carolina Heart Institute, Brody School of Medicine, East Carolina University, Greenville, NC, United States.,Department of Cardiovascular Sciences, Brody School of Medicine, East Carolina University, Greenville, NC, United States
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18
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Ryan TE, Yamaguchi DJ, Schmidt CA, Zeczycki TN, Shaikh SR, Brophy P, Green TD, Tarpey MD, Karnekar R, Goldberg EJ, Sparagna GC, Torres MJ, Annex BH, Neufer PD, Spangenburg EE, McClung JM. Extensive skeletal muscle cell mitochondriopathy distinguishes critical limb ischemia patients from claudicants. JCI Insight 2018; 3:123235. [PMID: 30385731 DOI: 10.1172/jci.insight.123235] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 10/02/2018] [Indexed: 12/31/2022] Open
Abstract
The most severe manifestation of peripheral arterial disease (PAD) is critical limb ischemia (CLI). CLI patients suffer high rates of amputation and mortality; accordingly, there remains a clear need both to better understand CLI and to develop more effective treatments. Gastrocnemius muscle was obtained from 32 older (51-84 years) non-PAD controls, 27 claudicating PAD patients (ankle-brachial index [ABI] 0.65 ± 0.21 SD), and 19 CLI patients (ABI 0.35 ± 0.30 SD) for whole transcriptome sequencing and comprehensive mitochondrial phenotyping. Comparable permeabilized myofiber mitochondrial function was paralleled by both similar mitochondrial content and related mRNA expression profiles in non-PAD control and claudicating patient tissues. Tissues from CLI patients, despite being histologically intact and harboring equivalent mitochondrial content, presented a unique bioenergetic signature. This signature was defined by deficits in permeabilized myofiber mitochondrial function and a unique pattern of both nuclear and mitochondrial encoded gene suppression. Moreover, isolated muscle progenitor cells retained both mitochondrial functional deficits and gene suppression observed in the tissue. These findings indicate that muscle tissues from claudicating patients and non-PAD controls were similar in both their bioenergetics profile and mitochondrial phenotypes. In contrast, CLI patient limb skeletal muscles harbor a unique skeletal muscle mitochondriopathy that represents a potentially novel therapeutic site for intervention.
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Affiliation(s)
- Terence E Ryan
- Department of Physiology.,East Carolina Diabetes and Obesity Institute
| | | | - Cameron A Schmidt
- Department of Physiology.,East Carolina Diabetes and Obesity Institute
| | - Tonya N Zeczycki
- East Carolina Diabetes and Obesity Institute.,Department of Biochemistry and Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
| | - Saame Raza Shaikh
- Department of Nutrition, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | | | - Thomas D Green
- Department of Physiology.,East Carolina Diabetes and Obesity Institute
| | - Michael D Tarpey
- Department of Physiology.,East Carolina Diabetes and Obesity Institute
| | - Reema Karnekar
- Department of Physiology.,East Carolina Diabetes and Obesity Institute
| | - Emma J Goldberg
- Department of Physiology.,East Carolina Diabetes and Obesity Institute
| | | | | | - Brian H Annex
- Division of Cardiovascular Medicine, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - P Darrell Neufer
- Department of Physiology.,East Carolina Diabetes and Obesity Institute
| | | | - Joseph M McClung
- Department of Physiology.,East Carolina Diabetes and Obesity Institute.,Department of Cardiovascular Sciences
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19
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Laing BT, Li P, Schmidt CA, Bunner W, Yuan Y, Landry T, Prete A, McClung JM, Huang H. AgRP/NPY Neuron Excitability Is Modulated by Metabotropic Glutamate Receptor 1 During Fasting. Front Cell Neurosci 2018; 12:276. [PMID: 30233321 PMCID: PMC6129575 DOI: 10.3389/fncel.2018.00276] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 08/08/2018] [Indexed: 12/17/2022] Open
Abstract
The potential to control feeding behavior via hypothalamic AgRP/NPY neurons has led to many approaches to modulate their excitability—particularly by glutamatergic input. In the present study using NPY-hrGFP reporter mice, we visualize AgRP/NPY neuronal metabotropic glutamate receptor 1 (mGluR1) expression and test the effect of fasting on mGluR1 function. Using the pharmacological agonist dihydroxyphenylglycine (DHPG), we demonstrate the enhanced capacity of mGluR1 to drive firing of AgRP/NPY neurons after overnight fasting, while antagonist 3-MATIDA reduces firing. Further, under synaptic blockade we demonstrate that DHPG acts directly on AgRP/NPY neurons to create a slow inward current. Using an in vitro approach, we show that emulation of intracellular signals associated with fasting by forskolin enhances DHPG induced phosphorylation of extracellularly regulated-signal kinase (1/2) in GT1-7 cell culture. We show in vivo that blocking mGluR1 by antagonist 3-MATIDA lowers fasting induced refeeding. In summary, this study identifies a novel layer of regulation on AgRP/NPY neurons integrated with whole body energy balance.
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Affiliation(s)
- Brenton T Laing
- Human Performance Laboratory, Department of Kinesiology, East Carolina University, Greenville, NC, United States.,East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States
| | - Peixin Li
- Human Performance Laboratory, Department of Kinesiology, East Carolina University, Greenville, NC, United States.,East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States
| | - Cameron A Schmidt
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States.,Department of Physiology, East Carolina University, Greenville, NC, United States
| | - Wyatt Bunner
- Human Performance Laboratory, Department of Kinesiology, East Carolina University, Greenville, NC, United States.,East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States
| | - Yuan Yuan
- Human Performance Laboratory, Department of Kinesiology, East Carolina University, Greenville, NC, United States.,East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States
| | - Taylor Landry
- Human Performance Laboratory, Department of Kinesiology, East Carolina University, Greenville, NC, United States.,East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States
| | - Amber Prete
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States
| | - Joseph M McClung
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States.,Department of Physiology, East Carolina University, Greenville, NC, United States
| | - Hu Huang
- Human Performance Laboratory, Department of Kinesiology, East Carolina University, Greenville, NC, United States.,East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States.,Department of Physiology, East Carolina University, Greenville, NC, United States
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20
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Tarpey MD, Amorese AJ, Balestrieri NP, Ryan TE, Schmidt CA, McClung JM, Spangenburg EE. Characterization and utilization of the flexor digitorum brevis for assessing skeletal muscle function. Skelet Muscle 2018; 8:14. [PMID: 29665848 PMCID: PMC5905177 DOI: 10.1186/s13395-018-0160-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Accepted: 04/03/2018] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND The ability to assess skeletal muscle function and delineate regulatory mechanisms is essential to uncovering therapeutic approaches that preserve functional independence in a disease state. Skeletal muscle provides distinct experimental challenges due to inherent differences across muscle groups, including fiber type and size that may limit experimental approaches. The flexor digitorum brevis (FDB) possesses numerous properties that offer the investigator a high degree of experimental flexibility to address specific hypotheses. To date, surprisingly few studies have taken advantage of the FDB to investigate mechanisms regulating skeletal muscle function. The purpose of this study was to characterize and experimentally demonstrate the value of the FDB muscle for scientific investigations. METHODS First, we characterized the FDB phenotype and provide reference comparisons to skeletal muscles commonly used in the field. We developed approaches allowing for experimental assessment of force production, in vitro and in vivo microscopy, and mitochondrial respiration to demonstrate the versatility of the FDB. As proof-of principle, we performed experiments to alter force production or mitochondrial respiration to validate the flexibility the FDB affords the investigator. RESULTS The FDB is made up of small predominantly type IIa and IIx fibers that collectively produce less peak isometric force than the extensor digitorum longus (EDL) or soleus muscles, but demonstrates a greater fatigue resistance than the EDL. Unlike the other muscles, inherent properties of the FDB muscle make it amenable to multiple in vitro- and in vivo-based microscopy methods. Due to its anatomical location, the FDB can be used in cardiotoxin-induced muscle injury protocols and is amenable to electroporation of cDNA with a high degree of efficiency allowing for an effective means of genetic manipulation. Using a novel approach, we also demonstrate methods for assessing mitochondrial respiration in the FDB, which are comparable to the commonly used gastrocnemius muscle. As proof of principle, short-term overexpression of Pgc1α in the FDB increased mitochondrial respiration rates. CONCLUSION The results highlight the experimental flexibility afforded the investigator by using the FDB muscle to assess mechanisms that regulate skeletal muscle function.
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Affiliation(s)
- Michael D. Tarpey
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC 27834 USA
| | - Adam J. Amorese
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC 27834 USA
| | - Nicholas P. Balestrieri
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC 27834 USA
| | - Terence E. Ryan
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC 27834 USA
| | - Cameron A. Schmidt
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC 27834 USA
| | - Joseph M. McClung
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC 27834 USA
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC 27834 USA
| | - Espen E. Spangenburg
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC 27834 USA
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC 27834 USA
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21
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Schmidt CA, Amorese AJ, Ryan TE, Goldberg EJ, Tarpey MD, Green TD, Karnekar RR, Yamaguchi DJ, Spangenburg EE, McClung JM. Strain-Dependent Variation in Acute Ischemic Muscle Injury. Am J Pathol 2018; 188:1246-1262. [PMID: 29454751 DOI: 10.1016/j.ajpath.2018.01.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 12/15/2017] [Accepted: 01/11/2018] [Indexed: 12/19/2022]
Abstract
Limited efficacy of clinical interventions for peripheral arterial disease necessitates a better understanding of the environmental and genetic determinants of tissue pathology. Existing research has largely ignored the early skeletal muscle injury response during hind limb ischemia (HLI). We compared the hind limb muscle response, after 6 hours of ischemia, in two mouse strains that differ dramatically in their postischemic extended recovery: C57BL/6J and BALB/cJ. Perfusion, measured by laser Doppler and normalized to the control limb, differed only slightly between strains after HLI (<12% across all measures). Similar (<10%) effect sizes in lectin-perfused vessel area and no differences in tissue oxygen saturation measured by reflectance spectroscopy were also found. Muscles from both strains were functionally impaired after HLI, but greater muscle necrosis and loss of dystrophin-positive immunostaining were observed in BALB/cJ muscle compared with C57BL/6J. Muscle cell-specific dystrophin loss and reduced viability were also detected in additional models of ischemia that were independent of residual perfusion differences. Our results indicate that factors other than the completeness of ischemia alone (ie, background genetics) influence the magnitude of acute ischemic muscle injury. These findings may have implications for future development of therapeutic interventions for limb ischemia and for understanding the phasic etiology of chronic and acute ischemic muscle pathophysiology.
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Affiliation(s)
- Cameron A Schmidt
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina; East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina
| | - Adam J Amorese
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina; East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina
| | - Terence E Ryan
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina; East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina
| | - Emma J Goldberg
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina; East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina
| | - Michael D Tarpey
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina; East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina
| | - Thomas D Green
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina; East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina
| | - Reema R Karnekar
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina; East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina
| | - Dean J Yamaguchi
- Department of Cardiovascular Sciences, East Carolina University, Greenville, North Carolina; Division of Vascular Surgery, East Carolina University, Greenville, North Carolina
| | - Espen E Spangenburg
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina; East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina
| | - Joseph M McClung
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina; East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina; Department of Cardiovascular Sciences, East Carolina University, Greenville, North Carolina.
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22
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McClung JM, McCord TJ, Ryan TE, Schmidt CA, Green TD, Southerland KW, Reinardy JL, Mueller SB, Venkatraman TN, Lascola CD, Keum S, Marchuk DA, Spangenburg EE, Dokun A, Annex BH, Kontos CD. BAG3 (Bcl-2-Associated Athanogene-3) Coding Variant in Mice Determines Susceptibility to Ischemic Limb Muscle Myopathy by Directing Autophagy. Circulation 2017; 136:281-296. [PMID: 28442482 PMCID: PMC5537727 DOI: 10.1161/circulationaha.116.024873] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 04/14/2017] [Indexed: 12/22/2022]
Abstract
BACKGROUND Critical limb ischemia is a manifestation of peripheral artery disease that carries significant mortality and morbidity risk in humans, although its genetic determinants remain largely unknown. We previously discovered 2 overlapping quantitative trait loci in mice, Lsq-1 and Civq-1, that affected limb muscle survival and stroke volume after femoral artery or middle cerebral artery ligation, respectively. Here, we report that a Bag3 variant (Ile81Met) segregates with tissue protection from hind-limb ischemia. METHODS We treated mice with either adeno-associated viruses encoding a control (green fluorescent protein) or 2 BAG3 (Bcl-2-associated athanogene-3) variants, namely Met81 or Ile81, and subjected the mice to hind-limb ischemia. RESULTS We found that the BAG3 Ile81Met variant in the C57BL/6 (BL6) mouse background segregates with protection from tissue necrosis in a shorter congenic fragment of Lsq-1 (C.B6-Lsq1-3). BALB/c mice treated with adeno-associated virus encoding the BL6 BAG3 variant (Ile81; n=25) displayed reduced limb-tissue necrosis and increased limb tissue perfusion compared with Met81- (n=25) or green fluorescent protein- (n=29) expressing animals. BAG3Ile81, but not BAG3Met81, improved ischemic muscle myopathy and muscle precursor cell differentiation and improved muscle regeneration in a separate, toxin-induced model of injury. Systemic injection of adeno-associated virus-BAG3Ile81 (n=9), but not BAG3Met81 (n=10) or green fluorescent protein (n=5), improved ischemic limb blood flow and limb muscle histology and restored muscle function (force production). Compared with BAG3Met81, BAG3Ile81 displayed improved binding to the small heat shock protein (HspB8) in ischemic skeletal muscle cells and enhanced ischemic muscle autophagic flux. CONCLUSIONS Taken together, our data demonstrate that genetic variation in BAG3 plays an important role in the prevention of ischemic tissue necrosis. These results highlight a pathway that preserves tissue survival and muscle function in the setting of ischemia.
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Affiliation(s)
- Joseph M McClung
- From Department of Physiology and Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC (J.M.M., T.E.R., C.A.S., T.D.G., E.E.S); Department of Medicine, Division of Cardiology (T.J.M., J.L.R., S.B.M., C.D.K.), Department of Surgery, Division of General Surgery (K.W.S.), Department of Pharmacology and Cancer Biology (J.L.R., S.B.M., C.D.K.), Department of Radiology (T.N.V., C.D.L.), and Department of Molecular Genetics and Microbiology (S.K., D.A.M.), Duke University Medical Center, Durham, NC; and Department of Medicine, Division of Endocrinology (A.D., B.H.A.), Division of Cardiovascular Medicine (B.H.A.), and Robert M. Berne Cardiovascular Research Center (B.H.A.), University of Virginia School of Medicine, Charlottesville.
| | - Timothy J McCord
- From Department of Physiology and Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC (J.M.M., T.E.R., C.A.S., T.D.G., E.E.S); Department of Medicine, Division of Cardiology (T.J.M., J.L.R., S.B.M., C.D.K.), Department of Surgery, Division of General Surgery (K.W.S.), Department of Pharmacology and Cancer Biology (J.L.R., S.B.M., C.D.K.), Department of Radiology (T.N.V., C.D.L.), and Department of Molecular Genetics and Microbiology (S.K., D.A.M.), Duke University Medical Center, Durham, NC; and Department of Medicine, Division of Endocrinology (A.D., B.H.A.), Division of Cardiovascular Medicine (B.H.A.), and Robert M. Berne Cardiovascular Research Center (B.H.A.), University of Virginia School of Medicine, Charlottesville
| | - Terence E Ryan
- From Department of Physiology and Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC (J.M.M., T.E.R., C.A.S., T.D.G., E.E.S); Department of Medicine, Division of Cardiology (T.J.M., J.L.R., S.B.M., C.D.K.), Department of Surgery, Division of General Surgery (K.W.S.), Department of Pharmacology and Cancer Biology (J.L.R., S.B.M., C.D.K.), Department of Radiology (T.N.V., C.D.L.), and Department of Molecular Genetics and Microbiology (S.K., D.A.M.), Duke University Medical Center, Durham, NC; and Department of Medicine, Division of Endocrinology (A.D., B.H.A.), Division of Cardiovascular Medicine (B.H.A.), and Robert M. Berne Cardiovascular Research Center (B.H.A.), University of Virginia School of Medicine, Charlottesville
| | - Cameron A Schmidt
- From Department of Physiology and Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC (J.M.M., T.E.R., C.A.S., T.D.G., E.E.S); Department of Medicine, Division of Cardiology (T.J.M., J.L.R., S.B.M., C.D.K.), Department of Surgery, Division of General Surgery (K.W.S.), Department of Pharmacology and Cancer Biology (J.L.R., S.B.M., C.D.K.), Department of Radiology (T.N.V., C.D.L.), and Department of Molecular Genetics and Microbiology (S.K., D.A.M.), Duke University Medical Center, Durham, NC; and Department of Medicine, Division of Endocrinology (A.D., B.H.A.), Division of Cardiovascular Medicine (B.H.A.), and Robert M. Berne Cardiovascular Research Center (B.H.A.), University of Virginia School of Medicine, Charlottesville
| | - Tom D Green
- From Department of Physiology and Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC (J.M.M., T.E.R., C.A.S., T.D.G., E.E.S); Department of Medicine, Division of Cardiology (T.J.M., J.L.R., S.B.M., C.D.K.), Department of Surgery, Division of General Surgery (K.W.S.), Department of Pharmacology and Cancer Biology (J.L.R., S.B.M., C.D.K.), Department of Radiology (T.N.V., C.D.L.), and Department of Molecular Genetics and Microbiology (S.K., D.A.M.), Duke University Medical Center, Durham, NC; and Department of Medicine, Division of Endocrinology (A.D., B.H.A.), Division of Cardiovascular Medicine (B.H.A.), and Robert M. Berne Cardiovascular Research Center (B.H.A.), University of Virginia School of Medicine, Charlottesville
| | - Kevin W Southerland
- From Department of Physiology and Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC (J.M.M., T.E.R., C.A.S., T.D.G., E.E.S); Department of Medicine, Division of Cardiology (T.J.M., J.L.R., S.B.M., C.D.K.), Department of Surgery, Division of General Surgery (K.W.S.), Department of Pharmacology and Cancer Biology (J.L.R., S.B.M., C.D.K.), Department of Radiology (T.N.V., C.D.L.), and Department of Molecular Genetics and Microbiology (S.K., D.A.M.), Duke University Medical Center, Durham, NC; and Department of Medicine, Division of Endocrinology (A.D., B.H.A.), Division of Cardiovascular Medicine (B.H.A.), and Robert M. Berne Cardiovascular Research Center (B.H.A.), University of Virginia School of Medicine, Charlottesville
| | - Jessica L Reinardy
- From Department of Physiology and Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC (J.M.M., T.E.R., C.A.S., T.D.G., E.E.S); Department of Medicine, Division of Cardiology (T.J.M., J.L.R., S.B.M., C.D.K.), Department of Surgery, Division of General Surgery (K.W.S.), Department of Pharmacology and Cancer Biology (J.L.R., S.B.M., C.D.K.), Department of Radiology (T.N.V., C.D.L.), and Department of Molecular Genetics and Microbiology (S.K., D.A.M.), Duke University Medical Center, Durham, NC; and Department of Medicine, Division of Endocrinology (A.D., B.H.A.), Division of Cardiovascular Medicine (B.H.A.), and Robert M. Berne Cardiovascular Research Center (B.H.A.), University of Virginia School of Medicine, Charlottesville
| | - Sarah B Mueller
- From Department of Physiology and Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC (J.M.M., T.E.R., C.A.S., T.D.G., E.E.S); Department of Medicine, Division of Cardiology (T.J.M., J.L.R., S.B.M., C.D.K.), Department of Surgery, Division of General Surgery (K.W.S.), Department of Pharmacology and Cancer Biology (J.L.R., S.B.M., C.D.K.), Department of Radiology (T.N.V., C.D.L.), and Department of Molecular Genetics and Microbiology (S.K., D.A.M.), Duke University Medical Center, Durham, NC; and Department of Medicine, Division of Endocrinology (A.D., B.H.A.), Division of Cardiovascular Medicine (B.H.A.), and Robert M. Berne Cardiovascular Research Center (B.H.A.), University of Virginia School of Medicine, Charlottesville
| | - Talaignair N Venkatraman
- From Department of Physiology and Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC (J.M.M., T.E.R., C.A.S., T.D.G., E.E.S); Department of Medicine, Division of Cardiology (T.J.M., J.L.R., S.B.M., C.D.K.), Department of Surgery, Division of General Surgery (K.W.S.), Department of Pharmacology and Cancer Biology (J.L.R., S.B.M., C.D.K.), Department of Radiology (T.N.V., C.D.L.), and Department of Molecular Genetics and Microbiology (S.K., D.A.M.), Duke University Medical Center, Durham, NC; and Department of Medicine, Division of Endocrinology (A.D., B.H.A.), Division of Cardiovascular Medicine (B.H.A.), and Robert M. Berne Cardiovascular Research Center (B.H.A.), University of Virginia School of Medicine, Charlottesville
| | - Christopher D Lascola
- From Department of Physiology and Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC (J.M.M., T.E.R., C.A.S., T.D.G., E.E.S); Department of Medicine, Division of Cardiology (T.J.M., J.L.R., S.B.M., C.D.K.), Department of Surgery, Division of General Surgery (K.W.S.), Department of Pharmacology and Cancer Biology (J.L.R., S.B.M., C.D.K.), Department of Radiology (T.N.V., C.D.L.), and Department of Molecular Genetics and Microbiology (S.K., D.A.M.), Duke University Medical Center, Durham, NC; and Department of Medicine, Division of Endocrinology (A.D., B.H.A.), Division of Cardiovascular Medicine (B.H.A.), and Robert M. Berne Cardiovascular Research Center (B.H.A.), University of Virginia School of Medicine, Charlottesville
| | - Sehoon Keum
- From Department of Physiology and Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC (J.M.M., T.E.R., C.A.S., T.D.G., E.E.S); Department of Medicine, Division of Cardiology (T.J.M., J.L.R., S.B.M., C.D.K.), Department of Surgery, Division of General Surgery (K.W.S.), Department of Pharmacology and Cancer Biology (J.L.R., S.B.M., C.D.K.), Department of Radiology (T.N.V., C.D.L.), and Department of Molecular Genetics and Microbiology (S.K., D.A.M.), Duke University Medical Center, Durham, NC; and Department of Medicine, Division of Endocrinology (A.D., B.H.A.), Division of Cardiovascular Medicine (B.H.A.), and Robert M. Berne Cardiovascular Research Center (B.H.A.), University of Virginia School of Medicine, Charlottesville
| | - Douglas A Marchuk
- From Department of Physiology and Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC (J.M.M., T.E.R., C.A.S., T.D.G., E.E.S); Department of Medicine, Division of Cardiology (T.J.M., J.L.R., S.B.M., C.D.K.), Department of Surgery, Division of General Surgery (K.W.S.), Department of Pharmacology and Cancer Biology (J.L.R., S.B.M., C.D.K.), Department of Radiology (T.N.V., C.D.L.), and Department of Molecular Genetics and Microbiology (S.K., D.A.M.), Duke University Medical Center, Durham, NC; and Department of Medicine, Division of Endocrinology (A.D., B.H.A.), Division of Cardiovascular Medicine (B.H.A.), and Robert M. Berne Cardiovascular Research Center (B.H.A.), University of Virginia School of Medicine, Charlottesville
| | - Espen E Spangenburg
- From Department of Physiology and Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC (J.M.M., T.E.R., C.A.S., T.D.G., E.E.S); Department of Medicine, Division of Cardiology (T.J.M., J.L.R., S.B.M., C.D.K.), Department of Surgery, Division of General Surgery (K.W.S.), Department of Pharmacology and Cancer Biology (J.L.R., S.B.M., C.D.K.), Department of Radiology (T.N.V., C.D.L.), and Department of Molecular Genetics and Microbiology (S.K., D.A.M.), Duke University Medical Center, Durham, NC; and Department of Medicine, Division of Endocrinology (A.D., B.H.A.), Division of Cardiovascular Medicine (B.H.A.), and Robert M. Berne Cardiovascular Research Center (B.H.A.), University of Virginia School of Medicine, Charlottesville
| | - Ayotunde Dokun
- From Department of Physiology and Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC (J.M.M., T.E.R., C.A.S., T.D.G., E.E.S); Department of Medicine, Division of Cardiology (T.J.M., J.L.R., S.B.M., C.D.K.), Department of Surgery, Division of General Surgery (K.W.S.), Department of Pharmacology and Cancer Biology (J.L.R., S.B.M., C.D.K.), Department of Radiology (T.N.V., C.D.L.), and Department of Molecular Genetics and Microbiology (S.K., D.A.M.), Duke University Medical Center, Durham, NC; and Department of Medicine, Division of Endocrinology (A.D., B.H.A.), Division of Cardiovascular Medicine (B.H.A.), and Robert M. Berne Cardiovascular Research Center (B.H.A.), University of Virginia School of Medicine, Charlottesville
| | - Brian H Annex
- From Department of Physiology and Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC (J.M.M., T.E.R., C.A.S., T.D.G., E.E.S); Department of Medicine, Division of Cardiology (T.J.M., J.L.R., S.B.M., C.D.K.), Department of Surgery, Division of General Surgery (K.W.S.), Department of Pharmacology and Cancer Biology (J.L.R., S.B.M., C.D.K.), Department of Radiology (T.N.V., C.D.L.), and Department of Molecular Genetics and Microbiology (S.K., D.A.M.), Duke University Medical Center, Durham, NC; and Department of Medicine, Division of Endocrinology (A.D., B.H.A.), Division of Cardiovascular Medicine (B.H.A.), and Robert M. Berne Cardiovascular Research Center (B.H.A.), University of Virginia School of Medicine, Charlottesville
| | - Christopher D Kontos
- From Department of Physiology and Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC (J.M.M., T.E.R., C.A.S., T.D.G., E.E.S); Department of Medicine, Division of Cardiology (T.J.M., J.L.R., S.B.M., C.D.K.), Department of Surgery, Division of General Surgery (K.W.S.), Department of Pharmacology and Cancer Biology (J.L.R., S.B.M., C.D.K.), Department of Radiology (T.N.V., C.D.L.), and Department of Molecular Genetics and Microbiology (S.K., D.A.M.), Duke University Medical Center, Durham, NC; and Department of Medicine, Division of Endocrinology (A.D., B.H.A.), Division of Cardiovascular Medicine (B.H.A.), and Robert M. Berne Cardiovascular Research Center (B.H.A.), University of Virginia School of Medicine, Charlottesville
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Schmidt CA, Ryan TE, Lin CT, Inigo MMR, Green TD, Brault JJ, Spangenburg EE, McClung JM. Diminished force production and mitochondrial respiratory deficits are strain-dependent myopathies of subacute limb ischemia. J Vasc Surg 2016; 65:1504-1514.e11. [PMID: 28024849 DOI: 10.1016/j.jvs.2016.04.041] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Accepted: 04/17/2016] [Indexed: 01/06/2023]
Abstract
OBJECTIVE Reduced skeletal muscle mitochondrial function might be a contributing mechanism to the myopathy and activity based limitations that typically plague patients with peripheral arterial disease (PAD). We hypothesized that mitochondrial dysfunction, myofiber atrophy, and muscle contractile deficits are inherently determined by the genetic background of regenerating ischemic mouse skeletal muscle, similar to how patient genetics affect the distribution of disease severity with clinical PAD. METHODS Genetically ischemia protected (C57BL/6) and susceptible (BALB/c) mice underwent either unilateral subacute hind limb ischemia (SLI) or myotoxic injury (cardiotoxin) for 28 days. Limbs were monitored for blood flow and tissue oxygen saturation and tissue was collected for the assessment of histology, muscle contractile force, gene expression, mitochondrial content, and respiratory function. RESULTS Despite similar tissue O2 saturation and mitochondrial content between strains, BALB/c mice suffered persistent ischemic myofiber atrophy (55.3% of C57BL/6) and muscle contractile deficits (approximately 25% of C57BL/6 across multiple stimulation frequencies). SLI also reduced BALB/c mitochondrial respiratory capacity, assessed in either isolated mitochondria (58.3% of C57BL/6 at SLI on day (d)7, 59.1% of C57BL/6 at SLI d28 across multiple conditions) or permeabilized myofibers (38.9% of C57BL/6 at SLI d7; 76.2% of C57BL/6 at SLI d28 across multiple conditions). SLI also resulted in decreased calcium retention capacity (56.0% of C57BL/6) in BALB/c mitochondria. Nonischemic cardiotoxin injury revealed similar recovery of myofiber area, contractile force, mitochondrial respiratory capacity, and calcium retention between strains. CONCLUSIONS Ischemia-susceptible BALB/c mice suffered persistent muscle atrophy, impaired muscle function, and mitochondrial respiratory deficits during SLI. Interestingly, parental strain susceptibility to myopathy appears specific to regenerative insults including an ischemic component. Our findings indicate that the functional deficits that plague PAD patients could include mitochondrial respiratory deficits genetically inherent to the regenerating muscle myofibers.
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Affiliation(s)
- Cameron A Schmidt
- Department of Physiology, East Carolina University, Greenville, NC; Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University, Greenville, NC
| | - Terence E Ryan
- Department of Physiology, East Carolina University, Greenville, NC; Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University, Greenville, NC
| | - Chien-Te Lin
- Department of Physiology, East Carolina University, Greenville, NC; Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University, Greenville, NC
| | - Melissa M R Inigo
- Department of Physiology, East Carolina University, Greenville, NC; Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University, Greenville, NC
| | - Tom D Green
- Department of Physiology, East Carolina University, Greenville, NC; Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University, Greenville, NC
| | - Jeffrey J Brault
- Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University, Greenville, NC; Department of Kinesiology, East Carolina University, Greenville, NC
| | - Espen E Spangenburg
- Department of Physiology, East Carolina University, Greenville, NC; Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University, Greenville, NC
| | - Joseph M McClung
- Department of Physiology, East Carolina University, Greenville, NC; Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University, Greenville, NC.
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Ryan TE, Schmidt CA, Green TD, Spangenburg EE, Neufer PD, McClung JM. Targeted Expression of Catalase to Mitochondria Protects Against Ischemic Myopathy in High-Fat Diet-Fed Mice. Diabetes 2016; 65:2553-68. [PMID: 27284110 PMCID: PMC5001179 DOI: 10.2337/db16-0387] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Accepted: 05/25/2016] [Indexed: 12/21/2022]
Abstract
Patients with type 2 diabetes respond poorly to treatments for peripheral arterial disease (PAD) and are more likely to present with the most severe manifestation of the disease, critical limb ischemia. The underlying mechanisms linking type 2 diabetes and the severity of PAD manifestation are not well understood. We sought to test whether diet-induced mitochondrial dysfunction and oxidative stress would increase the susceptibility of the peripheral limb to hindlimb ischemia (HLI). Six weeks of high-fat diet (HFD) in C57BL/6 mice was insufficient to alter skeletal muscle mitochondrial content and respiratory function or the size of ischemic lesion after HLI, despite reducing blood flow. However, 16 weeks of HFD similarly decreased ischemic limb blood flow, but also exacerbated limb tissue necrosis, increased the myopathic lesion size, reduced muscle regeneration, attenuated muscle function, and exacerbated ischemic mitochondrial dysfunction. Mechanistically, mitochondrial-targeted overexpression of catalase prevented the HFD-induced ischemic limb necrosis, myopathy, and mitochondrial dysfunction, despite no improvement in limb blood flow. These findings demonstrate that skeletal muscle mitochondria are a critical pathological link between type 2 diabetes and PAD. Furthermore, therapeutically targeting mitochondria and oxidant burden is an effective strategy to alleviate tissue loss and ischemic myopathy during PAD.
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Affiliation(s)
- Terence E Ryan
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC
| | - Cameron A Schmidt
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC
| | - Thomas D Green
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC
| | - Espen E Spangenburg
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC
| | - P Darrell Neufer
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC
| | - Joseph M McClung
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC
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Ryan TE, Schmidt CA, Alleman RJ, Tsang AM, Green TD, Neufer PD, Brown DA, McClung JM. Mitochondrial therapy improves limb perfusion and myopathy following hindlimb ischemia. J Mol Cell Cardiol 2016; 97:191-6. [PMID: 27262673 PMCID: PMC5002368 DOI: 10.1016/j.yjmcc.2016.05.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Revised: 05/17/2016] [Accepted: 05/30/2016] [Indexed: 11/27/2022]
Abstract
Critical limb ischemia is a devastating manifestation of peripheral arterial disease with no effective strategies for improving morbidity and mortality outcomes. We tested the hypothesis that cellular mitochondrial function is a key component of limb pathology and that improving mitochondrial function represents a novel paradigm for therapy. BALB/c mice were treated with a therapeutic mitochondrial-targeting peptide (MTP-131) and subjected to limb ischemia (HLI). Compared to vehicle control, MTP-131 rescued limb muscle capillary density and blood flow (64.7±11% of contralateral vs. 39.9±4%), and improved muscle regeneration. MTP-131 also increased electron transport system flux across all conditions at HLI day-7. In vitro, primary muscle cells exposed to experimental ischemia demonstrated markedly reduced (~75%) cellular respiration, which was rescued by MTP-131 during a recovery period. Compared to muscle cells, endothelial cell (HUVEC) respiration was inherently protected from ischemia (~30% reduction), but was also enhanced by MTP-131. These findings demonstrate an important link between ischemic tissue bioenergetics and limb blood flow and indicate that the mitochondria may be a pharmaceutical target for therapeutic intervention during critical limb ischemia.
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Affiliation(s)
- Terence E Ryan
- Department of Physiology, East Carolina University, Brody School of Medicine, Greenville, NC, USA; East Carolina Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC, USA
| | - Cameron A Schmidt
- Department of Physiology, East Carolina University, Brody School of Medicine, Greenville, NC, USA; East Carolina Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC, USA
| | - Rick J Alleman
- Department of Physiology, East Carolina University, Brody School of Medicine, Greenville, NC, USA; East Carolina Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC, USA
| | - Alvin M Tsang
- Department of Physiology, East Carolina University, Brody School of Medicine, Greenville, NC, USA; East Carolina Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC, USA
| | - Thomas D Green
- Department of Physiology, East Carolina University, Brody School of Medicine, Greenville, NC, USA; East Carolina Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC, USA
| | - P Darrell Neufer
- Department of Physiology, East Carolina University, Brody School of Medicine, Greenville, NC, USA; East Carolina Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC, USA
| | - David A Brown
- Department of Physiology, East Carolina University, Brody School of Medicine, Greenville, NC, USA; East Carolina Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC, USA
| | - Joseph M McClung
- Department of Physiology, East Carolina University, Brody School of Medicine, Greenville, NC, USA; East Carolina Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC, USA.
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Ryan TE, Schmidt CA, Green TD, Brown DA, Neufer PD, McClung JM. Mitochondrial Regulation of the Muscle Microenvironment in Critical Limb Ischemia. Front Physiol 2015; 6:336. [PMID: 26635622 PMCID: PMC4649016 DOI: 10.3389/fphys.2015.00336] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 11/02/2015] [Indexed: 01/11/2023] Open
Abstract
Critical limb ischemia (CLI) is the most severe clinical presentation of peripheral arterial disease and manifests as chronic limb pain at rest and/or tissue necrosis. Current clinical interventions are largely ineffective and therapeutic angiogenesis based trials have shown little efficacy, highlighting the dire need for new ideas and novel therapeutic approaches. Despite a decade of research related to skeletal muscle as a determinant of morbidity and mortality outcomes in CLI, very little progress has been made toward an effective therapy aimed directly at the muscle myopathies of this disease. Within the muscle cell, mitochondria are well positioned to modulate the ischemic cellular response, as they are the principal sites of cellular energy production and the major regulators of cellular redox charge and cell death. In this mini review, we update the crucial importance of skeletal muscle to CLI pathology and examine the evolving influence of muscle and endothelial cell mitochondria in the complex ischemic microenvironment. Finally, we discuss the novelty of muscle mitochondria as a therapeutic target for ischemic pathology in the context of the complex co-morbidities often associated with CLI.
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Affiliation(s)
- Terence E Ryan
- Department of Physiology, Brody School of Medicine, East Carolina University Greenville, NC, USA ; East Carolina Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University Greenville, NC, USA
| | - Cameron A Schmidt
- Department of Physiology, Brody School of Medicine, East Carolina University Greenville, NC, USA ; East Carolina Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University Greenville, NC, USA
| | - Tom D Green
- Department of Physiology, Brody School of Medicine, East Carolina University Greenville, NC, USA ; East Carolina Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University Greenville, NC, USA
| | - David A Brown
- Department of Physiology, Brody School of Medicine, East Carolina University Greenville, NC, USA ; East Carolina Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University Greenville, NC, USA
| | - P Darrell Neufer
- Department of Physiology, Brody School of Medicine, East Carolina University Greenville, NC, USA ; East Carolina Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University Greenville, NC, USA
| | - Joseph M McClung
- Department of Physiology, Brody School of Medicine, East Carolina University Greenville, NC, USA ; East Carolina Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University Greenville, NC, USA
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McClung JM, McCord TJ, Southerland K, Schmidt CA, Padgett ME, Ryan TE, Kontos CD. Subacute limb ischemia induces skeletal muscle injury in genetically susceptible mice independent of vascular density. J Vasc Surg 2015; 64:1101-1111.e2. [PMID: 26254821 DOI: 10.1016/j.jvs.2015.06.139] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Accepted: 06/07/2015] [Indexed: 01/01/2023]
Abstract
OBJECTIVE The primary preclinical model of peripheral artery disease, which involves acute limb ischemia (ALI), can result in appreciable muscle injury that is attributed to the acuity of the ischemic injury. A less acute model of murine limb ischemia using ameroid constrictors (ACs) has been developed in an attempt to mimic the chronic nature of human disease. However, there is currently little understanding of how genetics influence muscle injury following subacute arterial occlusion in the mouse. METHODS We investigated the influence of mouse genetics on skeletal muscle tissue survival, blood flow, and vascular density by subjecting two different mouse strains, C57BL/6 (BL6) and BALB/c, to ALI or subacute limb ischemia using single (1AC) or double (2AC) AC placement on the femoral artery. RESULTS Similar to ALI, the 2AC model resulted in significant tissue necrosis and limb perfusion deficits in genetically susceptible BALB/c but not BL6 mice. In the 1AC model, no outward evidence of tissue necrosis was observed, and there were no differences in limb blood flow between BL6 and BALB/c. However, BALB/c mice displayed significantly greater muscle injury, as evidenced by increased inflammation and myofiber atrophy, despite having no differences in CD31(+) and SMA(+) vascular density and area. BALB/c mice also displayed significantly greater centralized myonuclei, indicating increased muscle regeneration. CONCLUSIONS The susceptibility of skeletal muscle to ischemia-induced injury is at least partly independent of muscle blood flow and vascular density, consistent with a muscle cell autonomous response that is genetically determined. Further development of preclinical models of peripheral artery disease that more accurately reflect the nature of the human disease may allow more accurate identification of genetic targets for therapeutic intervention.
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Affiliation(s)
- Joseph M McClung
- Department of Physiology, East Carolina University, Brody Medical Center, Greenville, NC; Diabetes and Obesity Institute, East Carolina Heart Institute, Brody Medical Center, Greenville, NC.
| | - Timothy J McCord
- Division of Cardiology, Department of Medicine, Duke University Medical Center, Durham, NC
| | - Kevin Southerland
- Division of General Surgery, Department of Surgery, Duke University Medical Center, Durham, NC
| | - Cameron A Schmidt
- Department of Physiology, East Carolina University, Brody Medical Center, Greenville, NC; Diabetes and Obesity Institute, East Carolina Heart Institute, Brody Medical Center, Greenville, NC
| | - Michael E Padgett
- Division of Cardiology, Department of Medicine, Duke University Medical Center, Durham, NC
| | - Terence E Ryan
- Department of Physiology, East Carolina University, Brody Medical Center, Greenville, NC; Diabetes and Obesity Institute, East Carolina Heart Institute, Brody Medical Center, Greenville, NC
| | - Christopher D Kontos
- Division of Cardiology, Department of Medicine, Duke University Medical Center, Durham, NC; Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC
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McClung JM, Reinardy JL, Mueller SB, McCord TJ, Kontos CD, Brown DA, Hussain SNA, Schmidt CA, Ryan TE, Green TD. Muscle cell derived angiopoietin-1 contributes to both myogenesis and angiogenesis in the ischemic environment. Front Physiol 2015; 6:161. [PMID: 26042050 PMCID: PMC4436568 DOI: 10.3389/fphys.2015.00161] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 05/04/2015] [Indexed: 12/13/2022] Open
Abstract
Recent strategies to treat peripheral arterial disease (PAD) have focused on stem cell based therapies, which are believed to result in local secretion of vascular growth factors. Little is known, however, about the role of ischemic endogenous cells in this context. We hypothesized that ischemic muscle cells (MC) are capable of secreting growth factors that act as potent effectors of the local cellular regenerative environment. Both muscle and endothelial cells (ECs) were subjected to experimental ischemia, and conditioned medium (CM) from each was collected and analyzed to assess myogenic and/or angiogenic potential. In muscle progenitors, mRNA expression of VEGF and its cognate receptors (Nrp1, Flt, Flk) was present and decreased during myotube formation in vitro, and EC CM or VEGF increased myoblast proliferation. Angiopoietin-1 (Ang-1), Tie1, and Tie2 mRNA increased during MC differentiation in vitro. Exogenous Ang-1 enhanced myogenic (MyoD and Myogenin) mRNA in differentiating myoblasts and increased myosin heavy chain protein. Myotube formation was enhanced by MC CM and inhibited by EC CM. Ang-1 protein was present in CM from MCs isolated from both the genetically ischemia-susceptible BALB/c and ischemia-resistant C57BL/6 mouse strains, and chimeric Tie2 receptor trapping in situ ablated Ang-1's myogenic effects in vitro. Ang-1 or MC CM enhanced myotube formation in a mixed isolate of muscle progenitors as well as a myoblast co-culture with pluripotent mesenchymal cells (10T1/2) and this effect was abrogated by viral expression of the extracellular domain of Tie2 (AdsTie2). Furthermore, mesh/tube formation by HUVECs was enhanced by Ang-1 or MC CM and abrogated by Tie2 chimeric receptor trapping. Our results demonstrate the ability of muscle and endothelial cell-derived vascular growth factors, particularly Ang-1, to serve as multi-functional stimuli regulating crosstalk between blood vessels and muscle cells during regeneration from ischemic myopathy.
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Affiliation(s)
- Joseph M McClung
- Department of Physiology, Brody School of Medicine at East Carolina University Greenville, NC, USA ; Diabetes and Obesity Institute, Brody School of Medicine at East Carolina University Greenville, NC, USA
| | - Jessica L Reinardy
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine Durham, NC, USA
| | - Sarah B Mueller
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine Durham, NC, USA ; Medical Scientist Training Program, Duke University School of Medicine Durham, NC, USA
| | - Timothy J McCord
- Division of Cardiology, Department of Medicine, Duke University Medical Center Durham, NC, USA
| | - Christopher D Kontos
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine Durham, NC, USA ; Medical Scientist Training Program, Duke University School of Medicine Durham, NC, USA ; Division of Cardiology, Department of Medicine, Duke University Medical Center Durham, NC, USA
| | - David A Brown
- Department of Physiology, Brody School of Medicine at East Carolina University Greenville, NC, USA ; Diabetes and Obesity Institute, Brody School of Medicine at East Carolina University Greenville, NC, USA
| | - Sabah N A Hussain
- Meakins-Christie Laboratories, Department of Medicine, McGill University Health Centre, Royal Victoria Hospital, McGill University Montreal, QC, Canada ; Department of Critical Care, McGill University Health Centre, Royal Victoria Hospital, McGill University Montreal, QC, Canada
| | - Cameron A Schmidt
- Department of Physiology, Brody School of Medicine at East Carolina University Greenville, NC, USA ; Diabetes and Obesity Institute, Brody School of Medicine at East Carolina University Greenville, NC, USA
| | - Terence E Ryan
- Department of Physiology, Brody School of Medicine at East Carolina University Greenville, NC, USA ; Diabetes and Obesity Institute, Brody School of Medicine at East Carolina University Greenville, NC, USA
| | - Tom D Green
- Department of Physiology, Brody School of Medicine at East Carolina University Greenville, NC, USA ; Diabetes and Obesity Institute, Brody School of Medicine at East Carolina University Greenville, NC, USA
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Tomlinson IPM, Dunlop M, Campbell H, Zanke B, Gallinger S, Hudson T, Koessler T, Pharoah PD, Niittymäkix I, Tuupanenx S, Aaltonen LA, Hemminki K, Lindblom A, Försti A, Sieber O, Lipton L, van Wezel T, Morreau H, Wijnen JT, Devilee P, Matsuda K, Nakamura Y, Castellví-Bel S, Ruiz-Ponte C, Castells A, Carracedo A, Ho JWC, Sham P, Hofstra RMW, Vodicka P, Brenner H, Hampe J, Schafmayer C, Tepel J, Schreiber S, Völzke H, Lerch MM, Schmidt CA, Buch S, Moreno V, Villanueva CM, Peterlongo P, Radice P, Echeverry MM, Velez A, Carvajal-Carmona L, Scott R, Penegar S, Broderick P, Tenesa A, Houlston RS. COGENT (COlorectal cancer GENeTics): an international consortium to study the role of polymorphic variation on the risk of colorectal cancer. Br J Cancer 2010; 102:447-54. [PMID: 19920828 PMCID: PMC2816642 DOI: 10.1038/sj.bjc.6605338] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2009] [Revised: 09/03/2009] [Accepted: 09/03/2009] [Indexed: 12/24/2022] Open
Abstract
It is now recognised that a part of the inherited risk of colorectal cancer (CRC) can be explained by the co-inheritance of low-penetrance genetic variants. The accumulated experience to date in identifying these variants has served to highlight difficulties in conducting statistically and methodologically rigorous studies and follow-up analyses. The COGENT (COlorectal cancer GENeTics) consortium includes 20 research groups in Europe, Australia, the Americas, China and Japan. The overarching goal of COGENT is to identify and characterise low-penetrance susceptibility variants for CRC through association-based analyses. In this study, we review the rationale for identifying low-penetrance variants for CRC and our proposed strategy for establishing COGENT.
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Affiliation(s)
- I P M Tomlinson
- Molecular and Population Genetics, Nuffield Department of Medicine, University of Oxford, Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford OX3 7BN, UK
| | - M Dunlop
- Institute of Genetics and Molecular Medicine, University of Edinburgh, MRC-HGU, Western General Hospital, Crewe Road South, Edinburgh EH4 2XU, UK
| | - H Campbell
- Public Health Sciences, University of Edinburgh, Edinburgh EH89AG, UK
| | - B Zanke
- The Ontario Institute for Cancer Research, The MaRS Center, 101 College St, Suite 800, Toronto, Ontario, Canada M5G 1L7
- The University of Ottawa Faculty of Medicine, 101 Smythe Rd, Ottawa, Ontario, Canada K1H 8L6
- Cancer Care Ontario, 620 University Ave., Toronto, Ontario, Canada M5G 2L7
| | - S Gallinger
- Cancer Care Ontario, 620 University Ave., Toronto, Ontario, Canada M5G 2L7
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital and University of Toronto, 600 University Ave., Toronto, Ontario, Canada M5G 1X5
| | - T Hudson
- The Ontario Institute for Cancer Research, The MaRS Center, 101 College St, Suite 800, Toronto, Ontario, Canada M5G 1L7
| | - T Koessler
- Department of Oncology, University of Cambridge, Cambridge, UK
| | - P D Pharoah
- Department of Oncology, University of Cambridge, Cambridge, UK
| | - I Niittymäkix
- Department of Medical Genetics, Genome-Scale Biology Research Program, Biomedicum 9, University of Helsinki, Helsinki, Finland
| | - S Tuupanenx
- Department of Medical Genetics, Genome-Scale Biology Research Program, Biomedicum 9, University of Helsinki, Helsinki, Finland
| | - L A Aaltonen
- Department of Medical Genetics, Genome-Scale Biology Research Program, Biomedicum 9, University of Helsinki, Helsinki, Finland
| | - K Hemminki
- German Cancer Research Center, Heidelberg, Germany
| | - A Lindblom
- Department of Molecular Medicine and Surgery, Karolinska Institutet, CMM02, Stockholm S17176, Sweden
| | - A Försti
- Department of Molecular Medicine and Surgery, Karolinska Institutet, CMM02, Stockholm S17176, Sweden
| | - O Sieber
- LCCI Biomarker Laboratory, Ludwig Institute for Cancer Research, PO Box 2008, Royal Melbourne Hospital, VIC 3050, Australia
| | - L Lipton
- LCCI Biomarker Laboratory, Ludwig Institute for Cancer Research, PO Box 2008, Royal Melbourne Hospital, VIC 3050, Australia
| | - T van Wezel
- Department of Pathology, Leiden University Medical Center, ZA LEIDEN 2333, The Netherlands
| | - H Morreau
- Department of Pathology, Leiden University Medical Center, ZA LEIDEN 2333, The Netherlands
| | - J T Wijnen
- Departments of Human and Clinical Genetics, Leiden University Medical Center, ZA LEIDEN 2333, The Netherlands
| | - P Devilee
- Departments of Human and Clinical Genetics, Leiden University Medical Center, ZA LEIDEN 2333, The Netherlands
| | - K Matsuda
- Laboratory of Molecular Medicine, Human Genome Center, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Y Nakamura
- Laboratory of Molecular Medicine, Human Genome Center, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - S Castellví-Bel
- Department of Gastroenterology, Institut de Malalties Digestives i Metabòliques, Hospital Clínic, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), IDIBAPS, University of Barcelona, Barcelona, Catalonia, Spain
| | - C Ruiz-Ponte
- Fundacion Publica Galega de Medicina Xenomica (FPGMX), CIBERER, Genomic Medicine Group-University of Santiago de Compostela, Santiago de Compostela, Galicia, Spain
| | - A Castells
- Department of Gastroenterology, Institut de Malalties Digestives i Metabòliques, Hospital Clínic, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), IDIBAPS, University of Barcelona, Barcelona, Catalonia, Spain
| | - A Carracedo
- Fundacion Publica Galega de Medicina Xenomica (FPGMX), CIBERER, Genomic Medicine Group-University of Santiago de Compostela, Santiago de Compostela, Galicia, Spain
| | - J W C Ho
- The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - P Sham
- The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - R M W Hofstra
- Department of Genetics, University Medical Center Groningen, University of Groningen, P.O. Box 30.0001, Groningen 9700 RB, the Netherlands
| | - P Vodicka
- Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Videnska 1083, 14200 Prague 4, Czech Republic
| | - H Brenner
- Division of Clinical Epidemiology and Aging Research, German Cancer Research Center, Im Neuenheimer Feld 280, Heidelberg 69120, Germany
| | - J Hampe
- Department of General Internal Medicine, University Hospital, Schleswig-Holstein, Campus Kiel, Schittenhelmstraße 12, Kiel 24105, Germany
| | - C Schafmayer
- POPGEN Biobank, University Hospital Schleswig-Holstein, Campus Kiel, Schittenhelmstrasse 12, Kiel 24105, Germany
- Department of General and Thoracic Surgery, University Hospital Schleswig-Holstein, Campus Kiel, Arnold-Heller-Strasse 3, Kiel 24105, Germany
| | - J Tepel
- Department of General and Thoracic Surgery, University Hospital Schleswig-Holstein, Campus Kiel, Arnold-Heller-Strasse 3, Kiel 24105, Germany
| | - S Schreiber
- Department of General Internal Medicine, University Hospital, Schleswig-Holstein, Campus Kiel, Schittenhelmstraße 12, Kiel 24105, Germany
| | - H Völzke
- Institut für Community Medicine, University Hospital Greifswald, Walther-Rathenau-Strasse 48, Greifswald 17487, Germany
| | - M M Lerch
- Klinik für Innere Medizin A University Hospital Greifswald, Friedrich-Loeffler-Strasse 23a, Greifswald 17487, Germany
| | - C A Schmidt
- Klinik für Innere Medizin C, University Hospital Greifswald, Ferdinand-Sauerbruch-Strasse, Greifswald 17487, Germany
| | - S Buch
- Department of General Internal Medicine, University Hospital, Schleswig-Holstein, Campus Kiel, Schittenhelmstraße 12, Kiel 24105, Germany
| | - V Moreno
- IDIBELL-Catalan Institute of Oncology and University of Barcelona, Av Gran Via 199, L’Hospitalet, Barcelona 08907, Spain
| | - C M Villanueva
- Centre for Research in Environmental Epidemiology (CREAL), Municipal Institute of Medical Research (IMIM-Hospital del Mar) and CIBER Epidemiología y Salud Pública (CIBERESP), Doctor Aiguader, Barcelona 88 E-08003, Spain
| | - P Peterlongo
- Fondazione IRCCS Istituto Nazionale Tumori, and Fondazione IFOM, Istituto FIRC di Oncologia Molecolare, Milan, Italy
| | - P Radice
- Fondazione IRCCS Istituto Nazionale Tumori, and Fondazione IFOM, Istituto FIRC di Oncologia Molecolare, Milan, Italy
| | - M M Echeverry
- Departamento de Biología, Universidad del Tolima, Barrio Altos de Santa Helena, Ibague, Tolima, Colombia
| | - A Velez
- Departamento de Patología, Hospital Pablo Tobon Uribe, Calle 78 B No. 69-240, Medellín, Colombia
| | - L Carvajal-Carmona
- Molecular and Population Genetics, Nuffield Department of Medicine, University of Oxford, Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford OX3 7BN, UK
- Departamento de Biología, Universidad del Tolima, Barrio Altos de Santa Helena, Ibague, Tolima, Colombia
| | - R Scott
- Faculty of Health, School of Biomedical Sciences, University of Newcastle, NSW, Australia
| | - S Penegar
- Section of Cancer Genetics, Institute of Cancer Research, 15 Cotswold Rd, Sutton, Surrey SM2 5NG, UK
| | - P Broderick
- Section of Cancer Genetics, Institute of Cancer Research, 15 Cotswold Rd, Sutton, Surrey SM2 5NG, UK
| | - A Tenesa
- Institute of Genetics and Molecular Medicine, University of Edinburgh, MRC-HGU, Western General Hospital, Crewe Road South, Edinburgh EH4 2XU, UK
| | - R S Houlston
- Section of Cancer Genetics, Institute of Cancer Research, 15 Cotswold Rd, Sutton, Surrey SM2 5NG, UK
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Grabarczyk P, Przybylski GK, Depke M, Völker U, Bahr J, Assmus K, Bröker BM, Walther R, Schmidt CA. Inhibition of BCL11B expression leads to apoptosis of malignant but not normal mature T cells. Oncogene 2006; 26:3797-810. [PMID: 17173069 DOI: 10.1038/sj.onc.1210152] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The B-cell chronic lymphocytic leukemia (CLL)/lymphoma 11B gene (BCL11B) encodes a Krüppel-like zinc-finger protein, which plays a crucial role in thymopoiesis and has been associated with hematopoietic malignancies. It was hypothesized that BCL11B may act as a tumor-suppressor gene, but its precise function has not yet been elucidated. Here, we demonstrate that the survival of human T-cell leukemia and lymphoma cell lines is critically dependent on Bcl11b. Suppression of Bcl11b by RNA interference selectively induced apoptosis in transformed T cells whereas normal mature T cells remained unaffected. The apoptosis was effected by simultaneous activation of death receptor-mediated and intrinsic apoptotic pathways, most likely as a result of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) upregulation and suppression of the Bcl-xL antiapoptotic protein. Our data indicate an antiapoptotic function of Bcl11b. The resistance of normal mature T lymphocytes to Bcl11b suppression-induced apoptosis and restricted expression pattern make it an attractive therapeutic target in T-cell malignancies.
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Affiliation(s)
- P Grabarczyk
- Clinic for Internal Medicine C, University of Greifswald, Greifswald, Germany
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31
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Przybylski GK, Dik WA, Wanzeck J, Grabarczyk P, Majunke S, Martin-Subero JI, Siebert R, Dölken G, Ludwig WD, Verhaaf B, van Dongen JJM, Schmidt CA, Langerak AW. Disruption of the BCL11B gene through inv(14)(q11.2q32.31) results in the expression of BCL11B-TRDC fusion transcripts and is associated with the absence of wild-type BCL11B transcripts in T-ALL. Leukemia 2005; 19:201-8. [PMID: 15668700 DOI: 10.1038/sj.leu.2403619] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
T-cell acute lymphoblastic leukemia (T-ALL) is associated with chromosomal aberrations characterized by juxtaposition of proto-oncogenes to T-cell receptor gene loci (TCR), resulting in the deregulated transcription of these proto-oncogenes. Here, we describe the molecular characterization of a novel chromosomal aberration, inv(14)(q11.2q32.31), in a T-ALL sample, involving the recently described BCL11B gene and the TCRD locus. The inversion joined the 5' part of BCL11B, including exons 1-3, to the TRDD3 gene segment of the TCRD locus, whereas the reciprocal breakpoint fused the TRDV1 gene segment to the fourth exon of BCL11B. The TRDV1-BCL11B joining region was 1344 bp long and contained fragments derived from 20q11.22, 3p21.33 and from 11p12, indicating the complex character of this aberration. A strong expression of in-frame transcripts with truncated BCL11B and TCRD constant region (TRDC) were observed, but in contrast to normal T cells and other T-ALL samples, no wild-type BCL11B transcripts were detected in the T-ALL sample. Screening of 37 other T-ALLs revealed one additional case with expression of the BCL11B-TRDC fusion transcript. As BCL11B appears to play a key role in T-cell differentiation, BCL11B disruption and disturbed expression may contribute to the development of T-cell malignancies in man.
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Affiliation(s)
- G K Przybylski
- Institute of Human Genetics, Polish Academy of Sciences, Poznan, Poland.
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32
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Subklewe M, Nagy M, Schoch C, Jenisch S, Siebert R, Gesk S, Neuhaus P, Dörken B, Schmidt CA. Extramedullary manifestation of a donor-derived acute myeloid leukemia in a liver transplant patient. Leukemia 2004; 18:2050-3. [PMID: 15470493 DOI: 10.1038/sj.leu.2403498] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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33
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Busemann C, Schmidt CA, Fendrich K, Hoffmann W. [Lung metastases of colorectal tumors: clinical background and development of care supply]. Radiologe 2004; 44:711-4. [PMID: 15221153 DOI: 10.1007/s00117-004-1075-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The incidence of most cancers increases with age, including colorectal-, lung- and breast carcinomas. Each year, approximately 50,000 new cases of colorectal carcinoma (CRC) are diagnosed in Germany with a peak incidence around the age of 65. At diagnosis, 50% of CRC-cases show already metastases. Cure of metastatic disease with chemotherapy, radiology or surgery alone or in combination can be rarely achieved in this situation. However, palliative therapy regimens can significantly prolong life in most cases. Besides systemic therapy, minimal invasive techniques for tumor reduction are an interesting option in the palliative situation, especially in elderly patients. Yet the clinical impact of these new techniques has to be determined in future studies.
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Affiliation(s)
- C Busemann
- Klinik und Poliklinik für Innere Medizin C-Hämatologie und Onkologie, Ernst-Moritz-Arndt-Universität Greifswald
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34
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Ramos AS, Schmidt CA, Andrade SS, Fronza M, Rafferty B, Dalmora SL. Biological evaluation of recombinant human erythropoietin in pharmaceutical products. Braz J Med Biol Res 2003; 36:1561-9. [PMID: 14576911 DOI: 10.1590/s0100-879x2003001100014] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The potencies of mammalian cell-derived recombinant human erythropoietin pharmaceutical preparations, from a total of five manufacturers, were assessed by in vivo bioassay using standardized protocols. Eight-week-old normocythemic mice received a single subcutaneous injection followed by blood sampling 96 h later or multiple daily injections with blood sampling 24 h after the last injection. Reticulocyte counting by microscopic examination was employed as the end-point using the brilliant cresyl blue or selective hemolysis methods, together with automated flow cytometry. Different injection schedules were investigated and dose-response curves for the European Pharmacopoeia Biological Reference Preparation of erythropoietin were compared. Manual and automated methods of reticulocyte counting were correlated with respect to assay validity and precision. Using 8 mice per treatment group, intra-assay precision determined for all of the assays in the study showed coefficients of variation of 12.1-28.4% for the brilliant cresyl blue method, 14.1-30.8% for the selective hemolysis method and 8.5-19.7% for the flow cytometry method. Applying the single injection protocol, a combination of at least two independent assays was required to achieve the precision potency and confidence limits indicated by the manufacturers, while the multiple daily injection protocol yielded the same acceptable results within a single assay. Although the latter protocol using flow cytometry for reticulocyte counting gave more precise and reproducible results (intra-assay coefficients of variation: 5.9-14.2%), the well-characterized manual methods provide equally valid alternatives for the quality control of recombinant human erythropoietin therapeutic products.
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Affiliation(s)
- A S Ramos
- Departamento de Farmácia Industrial, Centro de Ciências da Saúde, Universidade Federal de Santa Maria, Santa Maria, RS, Brasil
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Andrade SS, Silveira RL, Schmidt CA, Júnior LB, Dalmora SL. Comparative evaluation of the human whole blood and human peripheral blood monocyte tests for pyrogens. Int J Pharm 2003; 265:115-24. [PMID: 14522124 DOI: 10.1016/j.ijpharm.2003.07.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Two different in vitro tests for pyrogens, using human peripheral blood monocytes (PBMNC) and diluted whole blood (WBC), respectively, were applied to different classes of parenteral medicinal products. Many of these products did not have a specified endotoxin limit concentration that was established as the maximum valid dilution to comply with the test. The results of the in vitro tests for pyrogens were compared with the results from the Limulus amoebocyte lysate (LAL) and rabbit pyrogen tests. The Second International Standard for endotoxin was used to calibrate all of the assays and the International Standard for IL-6 was used to calibrate the IL-6 ELISA which provided the readout for the in vitro tests for pyrogens. Preparatory tests were conducted to ensure that the "criteria for validity and precision of the standard curve" were satisfied and that the drugs being tested did not interfere in the tests. The PBMNC/IL-6 test had a detection limit of 0.06 EU/ml and spike recoveries were 62-165%. The whole blood/IL-6 test also had a detection limit of 0.06 EU/ml and spike recoveries were 58-132%. The application to the detection of non-endotoxin pyrogens needs to be evaluated in more detail, but the two in vitro tests for pyrogens showed good agreement overall, both with each other and with the LAL test and the rabbit pyrogen test for the detection of endotoxins.
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Affiliation(s)
- S S Andrade
- Industrial Pharmacy Department, Health Science Centre, Federal University of Santa Maria, 97.105-900, Santa Maria-RS, Brazil
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36
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Seehofer D, Rayes N, Steinmüller T, Schmidt CA, Settmacher U, Müller AR, Neuhaus P. Minimal impact of CMV infection on long-term survival after liver transplantation. Transplant Proc 2002; 34:2272-3. [PMID: 12270394 DOI: 10.1016/s0041-1345(02)03231-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- D Seehofer
- Department of General-, Visceral- and Transplant Surgery, Charité Campus Virchow, Humboldt University of Berlin, Berlin, Germany.
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Lupberger J, Kreuzer KA, Baskaynak G, Peters UR, le Coutre P, Schmidt CA. Quantitative analysis of beta-actin, beta-2-microglobulin and porphobilinogen deaminase mRNA and their comparison as control transcripts for RT-PCR. Mol Cell Probes 2002; 16:25-30. [PMID: 12005444 DOI: 10.1006/mcpr.2001.0392] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Quantitation of target mRNAs using the reverse-transcription polymerase chain reaction found a widespread field of application in diverse biomedical diagnostic assays. However, the problem of varying sample quality has to be solved by correcting target molecule amounts through detection of an endogenous control template. The choice of an appropriate reference gene is still object of debate as pseudogene co-amplification and expression level variations may limit the usefulness of some currently used reference reactions. We compared quantitative expression levels of the commonly used endogenous reference genes beta-actin (beta-actin), beta-2-microglobulin (beta2-MG) and porphobilinogen deaminase (PBDG) using the TaqMan chemistry. With these assays we investigated the respective expression patterns in K562 cells and leucocytes of normal individuals as well as of malignoma patients. In K562 cells 1544+246 beta-actin, 65+30 beta2-MG and 22+/-8 PBDG copies/cell were detected. In normal leucocytes 491+/-97 beta-actin, 40+/-17 beta2-MG and <1 PBDG copies/cell were quantified. Leucocytes of various malignancies exhibited 84+/-51 beta-actin, 106+/-8 beta2-MG and <1 PBDG copies/cell. We conclude that beta2-MG is the most suitable reference gene tested as its variation between different sample origins and within distinct cell types was acceptable low.
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Affiliation(s)
- J Lupberger
- Department of Medicine, Division of Hematology/Oncology, Charité Virchow-Klinikum, Humboldt University Berlin, FRG
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Przybylski GK, Oettle H, Siegert W, Schmidt CA. Novel T-cell receptor delta gene rearrangement involving a recombining element located 2.6 kb 3' from the Vdelta2 gene segment. Leuk Res 2001; 25:1059-65. [PMID: 11684277 DOI: 10.1016/s0145-2126(01)00081-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this study, we describe a novel T-cell receptor delta (TCRdelta) gene rearrangement observed in acute myeloid leukemia with coexpression of T-lymphoid antigens (Ly+AML) and in peripheral blood leukocytes (PBL) from one out of ten healthy donors. The rearrangement was identified by Southern blot analysis using a joining region (Jdelta1) specific probe and amplified by polymerase chain reaction (PCR) with a variable region (Vdelta2) and Jdelta1 specific primers. The nucleotide sequence analysis of an atypical 3000 bp PCR product allowed localization of the breakpoint within the TCRdelta gene locus, 2.6 kb 3' from the Vdelta2 gene segment. A regular Ddelta2-Ddelta3-Jdelta1 joining was found at the 3' end of the breakpoint, indicating that the rearrangement was mediated by the VDJ recombinase, but no TCRdelta gene segment was detected at the 5' end. Analysis of the germline sequence 3' from the breakpoint revealed an isolated recombination signal sequence (RSS) capable of initiating a rearrangement. The RSS motif described by us is the second TCRdelta recombining element (deltaRec2). The deltaRec2(Ddelta)Jdelta1 recombination is a rather rare event and can be found in acute leukemia and in PBL from healthy individuals. Most likely, the nonfunctional deltaRec2(Ddelta)Jdelta1 rearrangement is a transient step during the VDJ recombination. It may potentially lead to deletion of the deltaRec2(Ddelta)Jdelta1 complex and either to direct joining of a Vdelta region to one of the downstream Jdelta regions or to a rearrangement of the TCRalpha gene.
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Pickartz T, Ringel F, Wedde M, Renz H, Klein A, von Neuhoff N, Dreger P, Kreuzer KA, Schmidt CA, Srock S, Schoeler D, Schriever F. Selection of B-cell chronic lymphocytic leukemia cell variants by therapy with anti-CD20 monoclonal antibody rituximab. Exp Hematol 2001; 29:1410-6. [PMID: 11750099 DOI: 10.1016/s0301-472x(01)00753-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
OBJECTIVE Anti-CD20 chimeric monoclonal antibody rituximab (Mabthera; IDEC-C2B8) is currently tested in several clinical trials for the treatment of B-cell chronic lymphocytic leukemia (B-CLL). In the present study, we investigated whether rituximab therapy may select for CD20(-) subclones. MATERIALS AND METHODS Leukemic B-CLL cells were isolated from patients with B-CLL and sensitivity to rituximab-induced cell death was examined. Levels of CD20 protein and mRNA were determined using flow cytometry and real-time PCR, respectively. Clonality analyses of leukemic cells throughout rituximab therapy were performed by GeneScan analysis of patient clone specific rearrangements of the complementarity determining region III of the heavy chain immunoglobulin. RESULTS Cytotoxicity of rituximab in vitro did not depend on the protein levels of CD20. During therapy with rituximab CD20(+) B-CLL cells were depleted and CD20(-) leukemic cells emerged. After treatment, the initial CD20(+) B-CLL cell clone reexpanded. CD20(-) B-CLL cells retained their capacity to synthesize the CD20 molecule. CONCLUSIONS These data support the concept that in B-CLL rituximab treatment may not lead to the emergence of CD20(-) leukemic variants. Our findings support clinical studies investigating the benefit of prolonged period of rituximab therapy in B-CLL disease.
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MESH Headings
- Antibodies, Monoclonal/therapeutic use
- Antibodies, Monoclonal, Murine-Derived
- Antigens, CD20/genetics
- Antineoplastic Agents/therapeutic use
- Base Sequence
- DNA Primers
- Gene Expression Regulation, Neoplastic
- Genetic Variation
- Humans
- Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy
- Leukemia, Lymphocytic, Chronic, B-Cell/genetics
- Leukemia, Lymphocytic, Chronic, B-Cell/immunology
- Leukemia, Lymphocytic, Chronic, B-Cell/pathology
- Polymerase Chain Reaction
- RNA, Messenger/genetics
- Rituximab
- Transcription, Genetic
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Affiliation(s)
- T Pickartz
- Charité der Humboldt-Universität zu Berlin, Campus Virchow-Klinikum, Medizinische Klinik mit Schwerpunkt Hämatologie und Onkologie, Berlin, Germany
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40
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Einsele H, Bertz H, Beyer J, Kiehl MG, Runde V, Kolb HJ, Holler E, Beck R, Schwerdfeger R, Schumacher U, Hebart H, Martin H, Kienast J, Ullmann AJ, Maschmeyer G, Krüger W, Link H, Schmidt CA, Oettle H, Klingebiel T. [Epidemiology and interventional treatment strategies of infectious complications after allogenic stem-cell transplantation]. Dtsch Med Wochenschr 2001; 126:1278-84. [PMID: 11700570 DOI: 10.1055/s-2001-18331] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Affiliation(s)
- H Einsele
- Medizinische Klinik II, Universität Tübingen.
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41
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Rayes N, Seehofer D, Schmidt CA, Oettle H, Müller AR, Steinmüller T, Settmacher U, Bechstein WO, Neuhaus P. Prospective randomized trial to assess the value of preemptive oral therapy for CMV infection following liver transplantation. Transplantation 2001; 72:881-5. [PMID: 11571454 DOI: 10.1097/00007890-200109150-00024] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND With the development of sensitive tests to detect cytomegalovirus (CMV) viremia, preemptive approaches become a reasonable alternative to general CMV prophylaxis. We performed a randomized trial comparing pp65-antigenemia guided preemptive therapy using oral ganciclovir with symptom-triggered intravenous ganciclovir treatment. METHODS Eighty-eight of 372 liver transplant recipients developed antigenemia early after orthotopic liver transplantation. Twenty-eight symptomatic patients with antigenemia were excluded from randomization and treated with intravenous ganciclovir. Sixty pp65-antigen-positive asymptomatic patients were randomized to receive either oral ganciclovir 3x1 g/day for 14 days (group 1) or no preemptive treatment (group 2). Patients that developed CMV disease were treated with intravenous ganciclovir 2x5 mg/kg body weight for 14 days. The high-risk (Donor+/Recipient-) patients were equally distributed in the two study groups. RESULTS Three of 30 (10%) patients on oral ganciclovir developed mild to moderate CMV disease compared with 6/30 (20%) patients in the control group. In the Donor+/Recipient- patients, the incidence of CMV disease was 1/6 and 3/7. All disease episodes resolved after intravenous treatment. The 1- and 3-year patient and organ survival was the same in the study groups and in the patients with or without CMV infection. No deaths related to CMV occurred. CONCLUSIONS The positive predictive value of pp65-antigenemia for the development of CMV disease was very low, and, in 28/88 patients (32%), antigenemia did not precede symptoms. Therefore, pp65-antigenemia is of limited value in deciding on the timing and need for ganciclovir therapy after liver transplantation.
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Affiliation(s)
- N Rayes
- Department of Surgery, Charité Campus Virchow, Augustenburger Platz 1, 13355 Berlin, Germany
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42
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Kreuzer KA, Saborowski A, Lupberger J, Appelt C, Na IK, le Coutre P, Schmidt CA. Fluorescent 5'-exonuclease assay for the absolute quantification of Wilms' tumour gene (WT1) mRNA: implications for monitoring human leukaemias. Br J Haematol 2001; 114:313-8. [PMID: 11529849 DOI: 10.1046/j.1365-2141.2001.02912.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The Wilms' tumour gene (WT1) has been suggested as a powerful parameter for molecular monitoring of minimal residual disease (MRD) in leukaemias. However, molecular monitoring via WT1 RNA levels is far from being routinely performed, which is possibly owing to the complex and inaccurate quantitative reverse transcription polymerase chain reaction (RT-PCR) procedures. Using a newly-developed quantitative real time RT-PCR, we measured WT1 transcripts in peripheral blood leucocytes of patients with acute myeloid (AML), acute lymphoid (ALL) and chronic myeloid leukaemia (CML). While healthy blood donors did not show measurable amounts of WT1 transcripts, WT1 RNA levels were detectable in all types of leukaemia. Furthermore, intraindividual WT1 transcript kinetics were exclusively dependent on disease progression, treatment and subsequent disease outcome. Using this approach, we could distinguish between treatment response and failure within the first days of therapeutic intervention. Moreover, gradually rising WT1 levels over a period of weeks and months paralleled long-term disease progression and appeared to be a prognostic indicator for subsequent clinical relapse. A linear correlation between quantities of WT1 and bcr/abl fusion transcripts could be seen in CML. We conclude that quantitative assessment of WT1 transcripts using real-time PCR is an appropriate method for molecular monitoring of AML, ALL and CML, and can be used independently for both short- and long-term monitoring of leukaemia patients.
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MESH Headings
- Acute Disease
- Biomarkers, Tumor
- Blood Transfusion, Autologous
- Bone Marrow Transplantation
- Case-Control Studies
- Follow-Up Studies
- Fusion Proteins, bcr-abl/genetics
- Gene Expression
- Genes, Wilms Tumor
- Humans
- Leukemia/genetics
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/therapy
- Leukemia, Myeloid/genetics
- Leukocytes
- Lymphocyte Transfusion
- Neoplasm, Residual/genetics
- Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics
- Prognosis
- RNA, Messenger/analysis
- Reverse Transcriptase Polymerase Chain Reaction
- Transplantation, Homologous
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Affiliation(s)
- K A Kreuzer
- Klinik und Poliklinik für Innere Medizin m.S. Hämatologie und Onkologie, Campus Virchow-Klinikum, Medizinische Fakultät Charité der Humboldt-Universität zu Berlin, Germany
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43
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Endesfelder S, Krahn A, Kreuzer KA, Lass U, Schmidt CA, Jahrmarkt C, von Moers A, Speer A. Elevated p21 mRNA level in skeletal muscle of DMD patients and mdx mice indicates either an exhausted satellite cell pool or a higher p21 expression in dystrophin-deficient cells per se. J Mol Med (Berl) 2001; 78:569-74. [PMID: 11199330 DOI: 10.1007/s001090000153] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Abnormalities in proliferation and differentiation of the dystrophin-deficient muscle are a controversial aspect of the pathogenesis of Duchenne muscular dystrophy (DMD). Analyses of molecules involved in cell cycle modulation do not exist in this context. Cells withdrawn from the cell cycle permanently express p21. The fact that p2 1, in contrast to other cell cycle proteins, is not diminished when myotubes are reexposed to growth media, allocates this cyclin-dependent kinase inhibitor a special function. Here we report for the first time statistically increased p21 mRNA levels in dystrophin-deficient muscle tissue. Only 42% of conventional RT-PCRs from six muscle samples of human controls yielded positive results but almost all skeletal muscle biopsy samples (87%) from DMD patients (n=5). For p21 mRNA quantification in murine muscle samples we were able to use the exact real-time TaqMan PCR method due to generally higher p21 mRNA levels than in human muscles. In addition, contamination with fibroblasts can be excluded for the murine samples because they do not demonstrate fibrosis at the age of 350 days but start to lose their regenerative capacity. In accord with the results in humans, we observed p21 mRNA levels in mdx mice that were approx. four times as high as those in control mice. Elevated p21 mRNA level may indicate a shift in cell composition towards differentiated p21 expressing cells as a result of an exhausted pool of undifferentiated, non-p21-expressing satellite cells due to previous cycles of de- and regeneration. Alternatively, dystrophin-deficient cells per se may express higher p21 levels for unknown reasons. Although we cannot distinguish between these possibilities, the eventual transfec tion of a patient's own satellite cells with p21 antisense oligonucleotides may enable the dystrophic process to be influenced.
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MESH Headings
- Actins/genetics
- Actins/metabolism
- Adolescent
- Animals
- Child
- Humans
- Mice
- Mice, Inbred C57BL
- Mice, Inbred mdx
- Muscle, Skeletal/metabolism
- Muscle, Skeletal/pathology
- Muscular Dystrophy, Animal/genetics
- Muscular Dystrophy, Animal/metabolism
- Muscular Dystrophy, Animal/pathology
- Muscular Dystrophy, Duchenne/genetics
- Muscular Dystrophy, Duchenne/metabolism
- Muscular Dystrophy, Duchenne/pathology
- Mutation
- Oncogene Protein p21(ras)/genetics
- Oncogene Protein p21(ras)/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
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Affiliation(s)
- S Endesfelder
- Technische Fachhochschule Berlin, University of Applied Science, Department of Biotechnology, Germany
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44
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Ciftci O, Ullrich O, Schmidt CA, Diestel A, Hass R. Regulation of the nuclear proteasome activity in myelomonocytic human leukemia cells after adriamycin treatment. Blood 2001; 97:2830-8. [PMID: 11313278 DOI: 10.1182/blood.v97.9.2830] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Treatment of different human leukemia cell variants with the anthracycline adriamycin was associated with a rapid activation of the proteasome. Thus, proliferating U937, TUR, and retrodifferentiated U937 cells exhibited a 4.3-fold, 5.8-fold, and 4.3-fold proteasome activation within 15 minutes after adriamycin treatment, respectively. In contrast, little if any proteasome activation was detectable in a growth-arrested differentiated U937 population following adriamycin treatment. Further analysis of this mechanism revealed a significant reduction of adriamycin-induced proteasome activity after inhibition of poly(ADP-ribose) polymerase (PARP) by 3-aminobenzamide (3-ABA) in the proliferating leukemic cell types. These findings suggested that PARP is involved in the regulation of drug-induced proteasome activation. Indeed, anti-PARP immunoprecipitation experiments of adriamycin-treated cells revealed increasing levels of coprecipitated, enzymatically active proteasome particularly in the proliferating cell variants in contrast to the differentiated U937 cells, with a maximum after 15 minutes, and sensitivity to PARP inhibition by 3-ABA. The specific role of the PARP was investigated in U937 and TUR cell clones stably transfected with a constitutively active antisense PARP (asPARP) vector. Thus, asPARP-TUR cells developed a 25-fold increased sensitivity to adriamycin treatment. Furthermore, we investigated leukemic blasts isolated from acute myelogenous leukemia patients and obtained a similarly enhanced proteasome activity after adriamycin treatment, which was dependent on the PARP and thus could be coprecipitated with anti-PARP antibodies. Transient transfection of leukemic blasts with the asPARP vector significantly reduced the adriamycin-induced proteasome activation. These data suggest that the PARP-associated nuclear proteasome activation represents a potential target within chemotherapeutic defense mechanisms developed by leukemia cells.
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Affiliation(s)
- O Ciftci
- Department of Cell and Neurobiology, Institute of Anatomy, and Department of Hematology and Oncology, University Hospital Charité, Humboldt University, Berlin, Germany
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45
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Solassol J, Kreuzer KA, Lass U, Schmidt CA. Epstein-Barr virus DNA quantitation assessed by a real-time polymerase chain reaction in a case of Burkitt's lymphoma. Leuk Lymphoma 2001; 41:669-73. [PMID: 11378585 DOI: 10.3109/10428190109060358] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
A real-time PCR technique was used to quantify EBV DNA load in plasma, leukocytes, peritoneal cells, ascites and cerebrospinal fluid (CSF) at diagnosis and during the follow-up of a 21-year-old patient suffering from an abdominal form of EBV-associated Burkitt's lymphoma. The EBV DNA load correlated well with the clinical and biological remission status of the patient after chemotherapy confirming that EBV DNA quantitation in plasma and leukocytes from peripheral blood can be considered as a marker of the tumor load and can be analyzed in parallel for monitoring of EBV-related malignancies.
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Affiliation(s)
- J Solassol
- Abteilung für Innere Medizin und Poliklinik m.S. Hämatologie und Onkologie, Campus Virchow-Klinikum, Medizinische Fakultät Charité der Humboldt-Universität zu Berlin, Germany
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46
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Seeger K, Kreuzer KA, Lass U, Taube T, Buchwald D, Eckert C, Körner G, Schmidt CA, Henze G. Molecular quantification of response to therapy and remission status in TEL-AML1-positive childhood ALL by real-time reverse transcription polymerase chain reaction. Cancer Res 2001; 61:2517-22. [PMID: 11289124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Although TEL-AML1 positivity [translocation t(12;21)(p13;q22)], detected in 20-25% of initial childhood acute lymphoblastic leukemia (ALL), has been associated with an excellent prognosis, its positive predictive value is insufficient for appropriate treatment stratification considering reported prevalence in relapsed ALL (3-28%). Molecular quantification of response to therapy by PCR-based methods has been shown to improve risk assessment. Here, we report on the sensitive quantification of leukemia-specific TEL-AML1 fusion transcript levels normalized to beta-actin expression (sensitivity threshholds, 10(-5)) by a novel real-time reverse transcription-PCR (RQ-RT-PCR) based on fluorescent TaqMan technique providing early and rapid evidence on the treatment efficacy of children with initial or relapsed TEL-AML1+ ALL enrolled in frontline or relapse trials of the Berlin-Frankfurt-Münster (BFM)-Study Group. In initial ALL, TEL-AML1/beta-actin decrease was > or =10(5)-fold in 50% of patients after induction therapy (day 33) and stayed TEL-AML1-negative throughout therapy, which suggested high sensitivity of leukemic cells to antineoplastic therapy. The remaining patients were still TEL-AML1+ before reintensification (ratios, 0.7 x 10(-2):10(-4)). In relapsed ALL, TEL-AML1/beta-actin decrease was generally less pronounced at corresponding time points, and conversion to TEL-AML1 negativity was observed in 40% of patients. Most notably, subsequent relapses occurred only among molecular poor responders, whereas all early responders remain in their second complete remission. In conclusion, real-time quantification of TEL-AML1/beta-actin kinetics distinguishes distinct molecular response groups, and provides indications capable of directing therapeutic interventions for patients with TEL-AML1+ ALL. Before considering modification of therapy, results should be interpreted cautiously taking into account the long duration of remission associated with TEL-AML1+ ALL.
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Affiliation(s)
- K Seeger
- Department of Pediatric Oncology/Hematology, Otto-Heubner-Centrum Berlin, Germany.
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47
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Kreuzer KA, Bohn A, Lupberger J, Solassol J, le Coutre P, Schmidt CA. Simultaneous absolute quantification of target and control templates by real-time fluorescence reverse transcription-PCR using 4-(4'-dimethylaminophenylazo)benzoic acid as a dark quencher dye. Clin Chem 2001; 47:486-90. [PMID: 11238301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
BACKGROUND Despite the many advantages of real-time fluorescence reverse transcription-PCR (RT-PCR) as a quantitative analytical tool, simultaneous quantification of target and reference templates within one reaction has not been reported. We developed such an assay with an internal reference template. METHODS For quantification of target and reference sequences, we used two fluorescent probes in one reaction vessel on an ABI PRISM 7700 SDS instrument. Fluorescent probes were labeled with either 6-carboxy-fluorescein or hexachloro-6-carboxy-fluorescein as reporter dye and 4-(4'-dimethylaminophenylazo)benzoic acid (DABCYL) as a dark quencher fluorophore. To test the sensitivity and specificity of this assay, serial dilutions of reference and target templates were analyzed in one PCR reaction. In the presence of 10 beta-actin molecules as control templates, 10(5) bcr/abl molecules were amplified, and 10(5) beta-actin molecules were amplified in the presence of 10 bcr/abl copies. We also performed single and duplex measurements on samples from five patients with documented Philadelphia chromosome-positive chronic myelogenous leukemia disease courses (72 samples) and three with minor bcr/abl+ acute myelogenous leukemias (26 samples). RESULTS For M-bcr/abl duplex RT-PCR, the correlation coefficient (r) for starting template amounts and threshold cycle values was 0.99; for m-bcr/abl, r = 0.96, indicating a precise log-linear relation for 10-10(5) copies/100 ng of cDNA. In the same PCR reactions, r = 0.99 for beta-actin (coamplified with M-bcr/abl or m-bcr/abl) for 10(3)-10(7) copies/100 ng cDNA. The linear correlation coefficient for single and duplex measurements was 0.98 for M- and m-bcr/abl in patient samples. CONCLUSIONS DABCYL can be used as dark quencher fluorophore in real-time fluorescence PCR. The duplex fluorescence RT-PCR assay for bcr/abl and beta-actin transcripts allows monitoring of bcr/abl+ leukemias.
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Affiliation(s)
- K A Kreuzer
- Abteilung für Innere Medizin und Poliklinik m.S. Hämatologie und Onkologie, Campus Virchow-Klinikum, Medizinische Fakultät Charité der Humboldt-Universität zu Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
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48
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Rayes N, Seehofer D, Schmidt CA, Müller AR, Steinmüller T, Bechstein WO, Neuhaus P. Is preemptive therapy for CMV infection following liver transplantation superior to symptom-triggered treatment? Transplant Proc 2001; 33:1804. [PMID: 11267520 DOI: 10.1016/s0041-1345(00)02688-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- N Rayes
- Department of Surgery, Charite Campus Virchow, Berlin, Germany
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Abstract
Most contemporary models of hematopoiesis assume lineage fidelity of early progenitor cells. Along with this concept normal hematopoietic cells and the majority of leukemias express exclusively myeloid or lymphoid specific antigens. On the other hand, growing evidence exists challenging the lineage fidelity model. Chronic myeloid leukemia (CML) in the blast crisis may switch to acute lymphoblastic leukemia (ALL) and as a result of the chemotherapy ALL may converse to acute myeloid leukemia (AML). Furthermore, a substantial portion of leukemia cases, named acute mixed-lineage leukemia (AMLL), show simultaneous expression of both myeloid and lymphoid antigens. Immunoglobulin (Ig) and T-cell receptor (TCR) gene rearrangements, correlating with myeloid-lymphoid immunophenotype in AMLL, support the hypothesis of lineage infidelity of early progenitor cells, rather than the aberrant antigen expression. Based on a detailed characterization of AMLL we present a modified model of a "common myeloid/lymphoid progenitor cell". This hypothetical very early hematopoietic progenitor cell shows a transient expression of myeloid and B- or T-lymphoid antigen and may also have rearranged its Ig and/or TCR genes. Subsequently, myeloid or lymphoid markers are downregulated and the hematopoietic cell enters either myeloid, T-lymphoid or B-lymphoid differentiation pathway.
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Affiliation(s)
- C A Schmidt
- Humboldt Universität Berlin, Charite Campus Virchow, Augustenburger Platz 1, 13353 Berlin, Germany
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50
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Kern WV, Beyer J, Böhme A, Buchheidt D, Cornely O, Einsele H, Kisro J, Krüger W, Maschmeyer G, Ruhnke M, Schmidt CA, Schwartz S, Szelenyi H. [Prophylaxis of infection in neutropenic patients. Guidelines of the Working Party on Infections in Hematology and Oncology]. Dtsch Med Wochenschr 2000; 125:1582-8. [PMID: 11199452 DOI: 10.1055/s-2000-9552] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Affiliation(s)
- W V Kern
- Medizinische Klinik und Poliklinik, Universitätsklinikum Ulm.
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