1
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Medali T, Couchie D, Mougenot N, Mihoc M, Bergmann O, Derks W, Szweda LI, Yacoub M, Soliman S, Aguib Y, Wagdy K, Ibrahim AM, Friguet B, Rouis M. Thioredoxin-1 and its mimetic peptide improve systolic cardiac function and remodeling after myocardial infarction. FASEB J 2024; 38:e23291. [PMID: 38095283 DOI: 10.1096/fj.202300792rr] [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: 04/21/2023] [Revised: 10/14/2023] [Accepted: 10/24/2023] [Indexed: 12/18/2023]
Abstract
Myocardial infarction (MI) is characterized by a significant loss of cardiomyocytes (CMs), and it is suggested that reactive oxygen species (ROS) are involved in cell cycle arrest, leading to impaired CM renewal. Thioredoxin-1 (Trx-1) scavenges ROS and may play a role in restoring CM renewal. However, the truncated form of Trx-1, Trx-80, can compromise its efficacy by exerting antagonistic effects. Therefore, a Trx-1 mimetic peptide called CB3 was tested as an alternative way to restore CMs. This study aimed to investigate the effects of Trx-1, Trx-80, and CB3 on mice with experimental MI and study the underlying mechanism of CB3 on CMs. Mouse cardiac parameters were quantified by echocardiography, and infarction size and fibrosis determined using Trichrome and Picro-Sirius Red staining. The study found that Trx-1 and CB3 improved mouse cardiac function, reduced the size of cardiac infarct and fibrosis, and decreased the expression of cardiac inflammatory markers. Furthermore, CB3 polarized macrophages into M2 phenotype, reduced apoptosis and oxidative stress after MI, and increased CM proliferation in cell culture and in vivo. CB3 effectively protected against myocardial infarction and could represent a new class of compounds for treating MI.
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Affiliation(s)
- Tania Medali
- CNRS, INSERM, Institut de Biologie Paris Seine, Biological Adaptation and Ageing (B2A-IBPS), Sorbonne Université, Paris, France
| | - Dominique Couchie
- CNRS, INSERM, Institut de Biologie Paris Seine, Biological Adaptation and Ageing (B2A-IBPS), Sorbonne Université, Paris, France
| | - Nathalie Mougenot
- Faculté de Médecine, INSERM, Plateforme PECMV, UMS28, Sorbonne Université, Paris, France
| | - Maria Mihoc
- Faculté de Médecine, INSERM, Plateforme PECMV, UMS28, Sorbonne Université, Paris, France
| | - Olaf Bergmann
- Department of Cell and Molecular Biology, Karolinska Institute, Stockholm, Sweden
- CRTD, TU Dresden, Dresden, Germany
| | - Wouter Derks
- Department of Cell and Molecular Biology, Karolinska Institute, Stockholm, Sweden
- CRTD, TU Dresden, Dresden, Germany
| | - Luke I Szweda
- Division of Cardiology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | | | | | | | | | | | - Bertrand Friguet
- CNRS, INSERM, Institut de Biologie Paris Seine, Biological Adaptation and Ageing (B2A-IBPS), Sorbonne Université, Paris, France
| | - Mustapha Rouis
- CNRS, INSERM, Institut de Biologie Paris Seine, Biological Adaptation and Ageing (B2A-IBPS), Sorbonne Université, Paris, France
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2
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Cui M, Bezprozvannaya S, Hao T, Elnwasany A, Szweda LI, Liu N, Bassel-Duby R, Olson EN. Transcription factor NFYa controls cardiomyocyte metabolism and proliferation during mouse fetal heart development. Dev Cell 2023; 58:2867-2880.e7. [PMID: 37972593 PMCID: PMC11000264 DOI: 10.1016/j.devcel.2023.10.012] [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: 05/31/2023] [Revised: 08/22/2023] [Accepted: 10/24/2023] [Indexed: 11/19/2023]
Abstract
Cardiomyocytes are highly metabolic cells responsible for generating the contractile force in the heart. During fetal development and regeneration, these cells actively divide but lose their proliferative activity in adulthood. The mechanisms that coordinate their metabolism and proliferation are not fully understood. Here, we study the role of the transcription factor NFYa in developing mouse hearts. Loss of NFYa alters cardiomyocyte composition, causing a decrease in immature regenerative cells and an increase in trabecular and mature cardiomyocytes, as identified by spatial and single-cell transcriptome analyses. NFYa-deleted cardiomyocytes exhibited reduced proliferation and impaired mitochondrial metabolism, leading to cardiac growth defects and embryonic death. NFYa, interacting with cofactor SP2, activates genes linking metabolism and proliferation at the transcription level. Our study identifies a nodal role of NFYa in regulating prenatal cardiac growth and a previously unrecognized transcriptional control mechanism of heart metabolism, highlighting the importance of mitochondrial metabolism during heart development and regeneration.
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Affiliation(s)
- Miao Cui
- Department of Cardiology, Boston Children's Hospital, 300 Longwood Ave, Boston, MA 02115, USA; Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA.
| | - Svetlana Bezprozvannaya
- Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine and Sen. Paul D. Wellstone Muscular Dystrophy Specialized Research Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Tian Hao
- Department of Cardiology, Boston Children's Hospital, 300 Longwood Ave, Boston, MA 02115, USA
| | - Abdallah Elnwasany
- Division of Cardiology, Department of Internal Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Luke I Szweda
- Division of Cardiology, Department of Internal Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Ning Liu
- Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine and Sen. Paul D. Wellstone Muscular Dystrophy Specialized Research Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Rhonda Bassel-Duby
- Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine and Sen. Paul D. Wellstone Muscular Dystrophy Specialized Research Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Eric N Olson
- Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine and Sen. Paul D. Wellstone Muscular Dystrophy Specialized Research Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA.
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3
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Li Q, Li C, Elnwasany A, Sharma G, An YA, Zhang G, Elhelaly WM, Lin J, Gong Y, Chen G, Wang M, Zhao S, Dai C, Smart CD, Liu J, Luo X, Deng Y, Tan L, Lv SJ, Davidson SM, Locasale JW, Lorenzi PL, Malloy CR, Gillette TG, Vander Heiden MG, Scherer PE, Szweda LI, Fu G, Wang ZV. PKM1 Exerts Critical Roles in Cardiac Remodeling Under Pressure Overload in the Heart. Circulation 2021; 144:712-727. [PMID: 34102853 PMCID: PMC8405569 DOI: 10.1161/circulationaha.121.054885] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [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: 02/06/2023]
Abstract
BACKGROUND Metabolic remodeling precedes most alterations during cardiac hypertrophic growth under hemodynamic stress. The elevation of glucose utilization has been recognized as a hallmark of metabolic remodeling. However, its role in cardiac hypertrophic growth and heart failure in response to pressure overload remains to be fully illustrated. Here, we aimed to dissect the role of cardiac PKM1 (pyruvate kinase muscle isozyme 1) in glucose metabolic regulation and cardiac response under pressure overload. METHODS Cardiac-specific deletion of PKM1 was achieved by crossing the floxed PKM1 mouse model with the cardiomyocyte-specific Cre transgenic mouse. PKM1 transgenic mice were generated under the control of tetracycline response elements, and cardiac-specific overexpression of PKM1 was induced by doxycycline administration in adult mice. Pressure overload was triggered by transverse aortic constriction. Primary neonatal rat ventricular myocytes were used to dissect molecular mechanisms. Moreover, metabolomics and nuclear magnetic resonance spectroscopy analyses were conducted to determine cardiac metabolic flux in response to pressure overload. RESULTS We found that PKM1 expression is reduced in failing human and mouse hearts. It is important to note that cardiomyocyte-specific deletion of PKM1 exacerbates cardiac dysfunction and fibrosis in response to pressure overload. Inducible overexpression of PKM1 in cardiomyocytes protects the heart against transverse aortic constriction-induced cardiomyopathy and heart failure. At the mechanistic level, PKM1 is required for the augmentation of glycolytic flux, mitochondrial respiration, and ATP production under pressure overload. Furthermore, deficiency of PKM1 causes a defect in cardiomyocyte growth and a decrease in pyruvate dehydrogenase complex activity at both in vitro and in vivo levels. CONCLUSIONS These findings suggest that PKM1 plays an essential role in maintaining a homeostatic response in the heart under hemodynamic stress.
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Affiliation(s)
- Qinfeng Li
- Department of Cardiology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
- Key Laboratory of Cardiovascular Intervention and Regenerative Medicine of Zhejiang Province, Hangzhou, Zhejiang, China
- Division of Cardiology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Chao Li
- Division of Cardiology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Abdallah Elnwasany
- Division of Cardiology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Gaurav Sharma
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Yu A. An
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Guangyu Zhang
- Division of Cardiology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Waleed M. Elhelaly
- Division of Cardiology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Jun Lin
- Department of Cardiology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
- Key Laboratory of Cardiovascular Intervention and Regenerative Medicine of Zhejiang Province, Hangzhou, Zhejiang, China
| | - Yingchao Gong
- Department of Cardiology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
- Key Laboratory of Cardiovascular Intervention and Regenerative Medicine of Zhejiang Province, Hangzhou, Zhejiang, China
| | - Guihao Chen
- Division of Cardiology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Meihui Wang
- Department of Cardiology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
- Key Laboratory of Cardiovascular Intervention and Regenerative Medicine of Zhejiang Province, Hangzhou, Zhejiang, China
| | - Shangang Zhao
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Chongshan Dai
- Division of Cardiology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Charles D. Smart
- Division of Cardiology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Juan Liu
- Department of Pharmacology & Cancer Biology, Duke University School of Medicine, Durham, North Carolina, USA
| | - Xiang Luo
- Division of Cardiology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Yingfeng Deng
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Lin Tan
- Metabolomics Core Facility, Department of Bioinformatics & Computational Biology, University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Shuang-Jie Lv
- State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China
| | - Shawn M. Davidson
- Koch Institute for Integrative Cancer Research and Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Jason W. Locasale
- Department of Pharmacology & Cancer Biology, Duke University School of Medicine, Durham, North Carolina, USA
| | - Philip L. Lorenzi
- Metabolomics Core Facility, Department of Bioinformatics & Computational Biology, University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Craig R. Malloy
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Thomas G. Gillette
- Division of Cardiology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Matthew G. Vander Heiden
- Koch Institute for Integrative Cancer Research and Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
- Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Philipp E. Scherer
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Luke I. Szweda
- Division of Cardiology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Guosheng Fu
- Department of Cardiology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
- Key Laboratory of Cardiovascular Intervention and Regenerative Medicine of Zhejiang Province, Hangzhou, Zhejiang, China
| | - Zhao V. Wang
- Division of Cardiology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
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4
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Tong D, Schiattarella GG, Jiang N, Altamirano F, Szweda PA, Elnwasany A, Lee DI, Yoo H, Kass DA, Szweda LI, Lavandero S, Verdin E, Gillette TG, Hill JA. NAD + Repletion Reverses Heart Failure With Preserved Ejection Fraction. Circ Res 2021; 128:1629-1641. [PMID: 33882692 DOI: 10.1161/circresaha.120.317046] [Citation(s) in RCA: 82] [Impact Index Per Article: 27.3] [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] [Indexed: 02/06/2023]
Abstract
[Figure: see text].
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Affiliation(s)
- Dan Tong
- Internal Medicine (Cardiology) (D.T., G.G.S., N.J., F.A., P.A.S., A.E., H.Y., L.I.S., S.L., T.G.G., J.A.H.), University of Texas Southwestern Medical Center, Dallas, TX
| | - Gabriele G Schiattarella
- Internal Medicine (Cardiology) (D.T., G.G.S., N.J., F.A., P.A.S., A.E., H.Y., L.I.S., S.L., T.G.G., J.A.H.), University of Texas Southwestern Medical Center, Dallas, TX
| | - Nan Jiang
- Internal Medicine (Cardiology) (D.T., G.G.S., N.J., F.A., P.A.S., A.E., H.Y., L.I.S., S.L., T.G.G., J.A.H.), University of Texas Southwestern Medical Center, Dallas, TX
| | - Francisco Altamirano
- Internal Medicine (Cardiology) (D.T., G.G.S., N.J., F.A., P.A.S., A.E., H.Y., L.I.S., S.L., T.G.G., J.A.H.), University of Texas Southwestern Medical Center, Dallas, TX
| | - Pamela A Szweda
- Internal Medicine (Cardiology) (D.T., G.G.S., N.J., F.A., P.A.S., A.E., H.Y., L.I.S., S.L., T.G.G., J.A.H.), University of Texas Southwestern Medical Center, Dallas, TX
| | - Abdallah Elnwasany
- Internal Medicine (Cardiology) (D.T., G.G.S., N.J., F.A., P.A.S., A.E., H.Y., L.I.S., S.L., T.G.G., J.A.H.), University of Texas Southwestern Medical Center, Dallas, TX
| | - Dong I Lee
- Department of Medicine (Cardiology), Johns Hopkins University School of Medicine, Baltimore MD (D.I.K., D.A.K.)
| | - Heesoo Yoo
- Internal Medicine (Cardiology) (D.T., G.G.S., N.J., F.A., P.A.S., A.E., H.Y., L.I.S., S.L., T.G.G., J.A.H.), University of Texas Southwestern Medical Center, Dallas, TX
| | - David A Kass
- Department of Medicine (Cardiology), Johns Hopkins University School of Medicine, Baltimore MD (D.I.K., D.A.K.)
| | - Luke I Szweda
- Internal Medicine (Cardiology) (D.T., G.G.S., N.J., F.A., P.A.S., A.E., H.Y., L.I.S., S.L., T.G.G., J.A.H.), University of Texas Southwestern Medical Center, Dallas, TX
| | - Sergio Lavandero
- Internal Medicine (Cardiology) (D.T., G.G.S., N.J., F.A., P.A.S., A.E., H.Y., L.I.S., S.L., T.G.G., J.A.H.), University of Texas Southwestern Medical Center, Dallas, TX.,Advanced Center for Chronic Diseases (ACCDiS) & Corporacion Estudios Cientificos de las Enfermedades Cronicas (CECEC), Faculty of Chemical & Pharmaceutical Sciences & Faculty of Medicine, University of Chile, Santiago (S.L.)
| | - Eric Verdin
- Bulk Institute for Research on Aging, Novato, CA (E.V.)
| | - Thomas G Gillette
- Internal Medicine (Cardiology) (D.T., G.G.S., N.J., F.A., P.A.S., A.E., H.Y., L.I.S., S.L., T.G.G., J.A.H.), University of Texas Southwestern Medical Center, Dallas, TX
| | - Joseph A Hill
- Internal Medicine (Cardiology) (D.T., G.G.S., N.J., F.A., P.A.S., A.E., H.Y., L.I.S., S.L., T.G.G., J.A.H.), University of Texas Southwestern Medical Center, Dallas, TX.,Molecular Biology (J.A.H.), University of Texas Southwestern Medical Center, Dallas, TX
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5
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Joffin N, Paschoal VA, Gliniak CM, Crewe C, Elnwasany A, Szweda LI, Zhang Q, Hepler C, Kusminski CM, Gordillo R, Oh DY, Gupta RK, Scherer PE. Mitochondrial metabolism is a key regulator of the fibro-inflammatory and adipogenic stromal subpopulations in white adipose tissue. Cell Stem Cell 2021; 28:702-717.e8. [PMID: 33539722 DOI: 10.1016/j.stem.2021.01.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [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: 03/30/2020] [Revised: 10/17/2020] [Accepted: 01/05/2021] [Indexed: 12/19/2022]
Abstract
The adipose tissue stroma is a rich source of molecularly distinct stem and progenitor cell populations with diverse functions in metabolic regulation, adipogenesis, and inflammation. The ontology of these populations and the mechanisms that govern their behaviors in response to stimuli, such as overfeeding, however, are unclear. Here, we show that the developmental fates and functional properties of adipose platelet-derived growth factor receptor beta (PDGFRβ)+ progenitor subpopulations are tightly regulated by mitochondrial metabolism. Reducing the mitochondrial β-oxidative capacity of PDGFRβ+ cells via inducible expression of MitoNEET drives a pro-inflammatory phenotype in adipose progenitors and alters lineage commitment. Furthermore, disrupting mitochondrial function in PDGFRβ+ cells rapidly induces alterations in immune cell composition in lean mice and impacts expansion of adipose tissue in diet-induced obesity. The adverse effects on adipose tissue remodeling can be reversed by restoring mitochondrial activity in progenitors, suggesting therapeutic potential for targeting energy metabolism in these cells.
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Affiliation(s)
- Nolwenn Joffin
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Vivian A Paschoal
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Christy M Gliniak
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Clair Crewe
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Abdallah Elnwasany
- Division of Cardiology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Luke I Szweda
- Division of Cardiology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Qianbin Zhang
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Chelsea Hepler
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Christine M Kusminski
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Ruth Gordillo
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Da Young Oh
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Rana K Gupta
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Philipp E Scherer
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA; Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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6
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Kim SY, Zhang X, Schiattarella GG, Altamirano F, Ramos TAR, French KM, Jiang N, Szweda PA, Evers BM, May HI, Luo X, Li H, Szweda LI, Maracaja-Coutinho V, Lavandero S, Gillette TG, Hill JA. Epigenetic Reader BRD4 (Bromodomain-Containing Protein 4) Governs Nucleus-Encoded Mitochondrial Transcriptome to Regulate Cardiac Function. Circulation 2020; 142:2356-2370. [PMID: 33113340 DOI: 10.1161/circulationaha.120.047239] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [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: 12/13/2022]
Abstract
BACKGROUND BET (bromodomain and extraterminal) epigenetic reader proteins, in particular BRD4 (bromodomain-containing protein 4), have emerged as potential therapeutic targets in a number of pathological conditions, including cancer and cardiovascular disease. Small-molecule BET protein inhibitors such as JQ1 have demonstrated efficacy in reversing cardiac hypertrophy and heart failure in preclinical models. Yet, genetic studies elucidating the biology of BET proteins in the heart have not been conducted to validate pharmacological findings and to unveil potential pharmacological side effects. METHODS By engineering a cardiomyocyte-specific BRD4 knockout mouse, we investigated the role of BRD4 in cardiac pathophysiology. We performed functional, transcriptomic, and mitochondrial analyses to evaluate BRD4 function in developing and mature hearts. RESULTS Unlike pharmacological inhibition, loss of BRD4 protein triggered progressive declines in myocardial function, culminating in dilated cardiomyopathy. Transcriptome analysis of BRD4 knockout mouse heart tissue identified early and specific disruption of genes essential to mitochondrial energy production and homeostasis. Functional analysis of isolated mitochondria from these hearts confirmed that BRD4 ablation triggered significant changes in mitochondrial electron transport chain protein expression and activity. Computational analysis identified candidate transcription factors participating in the BRD4-regulated transcriptome. In particular, estrogen-related receptor α, a key nuclear receptor in metabolic gene regulation, was enriched in promoters of BRD4-regulated mitochondrial genes. CONCLUSIONS In aggregate, we describe a previously unrecognized role for BRD4 in regulating cardiomyocyte mitochondrial homeostasis, observing that its function is indispensable to the maintenance of normal cardiac function.
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MESH Headings
- Animals
- Cardiomyopathy, Dilated/genetics
- Cardiomyopathy, Dilated/metabolism
- Cardiomyopathy, Dilated/pathology
- Cardiomyopathy, Dilated/physiopathology
- Cell Nucleus/genetics
- Cell Nucleus/metabolism
- Cell Nucleus/pathology
- Electron Transport Chain Complex Proteins/genetics
- Electron Transport Chain Complex Proteins/metabolism
- Energy Metabolism/genetics
- Epigenesis, Genetic
- Estrogen Receptor alpha/genetics
- Estrogen Receptor alpha/metabolism
- Gene Expression Profiling
- Heart Failure/genetics
- Heart Failure/metabolism
- Heart Failure/pathology
- Heart Failure/physiopathology
- Mice, Knockout
- Mitochondria, Heart/genetics
- Mitochondria, Heart/metabolism
- Mitochondria, Heart/pathology
- Myocytes, Cardiac/metabolism
- Myocytes, Cardiac/pathology
- Nuclear Proteins/genetics
- Nuclear Proteins/metabolism
- Transcription Factors/genetics
- Transcription Factors/metabolism
- Transcriptome
- Ventricular Dysfunction, Left/genetics
- Ventricular Dysfunction, Left/metabolism
- Ventricular Dysfunction, Left/pathology
- Ventricular Dysfunction, Left/physiopathology
- Ventricular Function, Left/genetics
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Affiliation(s)
- Soo Young Kim
- Division of Cardiology, Department of Internal Medicine (S.Y.K., G.G.S., F.A., K.M.F., N.J., P.A.S., H.I.M., X.L., L.I.S., S.L., T.G.G., J.A.H.), University of Texas Southwestern, Dallas
| | - Xin Zhang
- Institute of Model Animal, Wuhan University, China (X.Z., H.L.)
| | - Gabriele G Schiattarella
- Division of Cardiology, Department of Internal Medicine (S.Y.K., G.G.S., F.A., K.M.F., N.J., P.A.S., H.I.M., X.L., L.I.S., S.L., T.G.G., J.A.H.), University of Texas Southwestern, Dallas
| | - Francisco Altamirano
- Division of Cardiology, Department of Internal Medicine (S.Y.K., G.G.S., F.A., K.M.F., N.J., P.A.S., H.I.M., X.L., L.I.S., S.L., T.G.G., J.A.H.), University of Texas Southwestern, Dallas
- Department of Cardiovascular Sciences, Houston Methodist Research Institute, TX (F.A.)
| | - Thais A R Ramos
- Advanced Center for Chronic Disease, Faculty of Chemical and Pharmaceutical Sciences & Faculty of Medicine, University of Chile, Santiago (T.A.R.R., V.M.-C., S.L.)
- Bioinformatics Multidisciplinary Environment, Digital Metropolis Institute, Federal University of Rio Grande do Norte, Natal, Brazil (T.A.R.R., V.M.-C.)
| | - Kristin M French
- Division of Cardiology, Department of Internal Medicine (S.Y.K., G.G.S., F.A., K.M.F., N.J., P.A.S., H.I.M., X.L., L.I.S., S.L., T.G.G., J.A.H.), University of Texas Southwestern, Dallas
| | - Nan Jiang
- Division of Cardiology, Department of Internal Medicine (S.Y.K., G.G.S., F.A., K.M.F., N.J., P.A.S., H.I.M., X.L., L.I.S., S.L., T.G.G., J.A.H.), University of Texas Southwestern, Dallas
| | - Pamela A Szweda
- Division of Cardiology, Department of Internal Medicine (S.Y.K., G.G.S., F.A., K.M.F., N.J., P.A.S., H.I.M., X.L., L.I.S., S.L., T.G.G., J.A.H.), University of Texas Southwestern, Dallas
| | - Bret M Evers
- Department of Pathology (B.M.E.), University of Texas Southwestern, Dallas
| | - Herman I May
- Division of Cardiology, Department of Internal Medicine (S.Y.K., G.G.S., F.A., K.M.F., N.J., P.A.S., H.I.M., X.L., L.I.S., S.L., T.G.G., J.A.H.), University of Texas Southwestern, Dallas
| | - Xiang Luo
- Division of Cardiology, Department of Internal Medicine (S.Y.K., G.G.S., F.A., K.M.F., N.J., P.A.S., H.I.M., X.L., L.I.S., S.L., T.G.G., J.A.H.), University of Texas Southwestern, Dallas
| | - Hongliang Li
- Institute of Model Animal, Wuhan University, China (X.Z., H.L.)
| | - Luke I Szweda
- Division of Cardiology, Department of Internal Medicine (S.Y.K., G.G.S., F.A., K.M.F., N.J., P.A.S., H.I.M., X.L., L.I.S., S.L., T.G.G., J.A.H.), University of Texas Southwestern, Dallas
| | - Vinicius Maracaja-Coutinho
- Advanced Center for Chronic Disease, Faculty of Chemical and Pharmaceutical Sciences & Faculty of Medicine, University of Chile, Santiago (T.A.R.R., V.M.-C., S.L.)
- Bioinformatics Multidisciplinary Environment, Digital Metropolis Institute, Federal University of Rio Grande do Norte, Natal, Brazil (T.A.R.R., V.M.-C.)
| | - Sergio Lavandero
- Division of Cardiology, Department of Internal Medicine (S.Y.K., G.G.S., F.A., K.M.F., N.J., P.A.S., H.I.M., X.L., L.I.S., S.L., T.G.G., J.A.H.), University of Texas Southwestern, Dallas
- Advanced Center for Chronic Disease, Faculty of Chemical and Pharmaceutical Sciences & Faculty of Medicine, University of Chile, Santiago (T.A.R.R., V.M.-C., S.L.)
| | - Thomas G Gillette
- Division of Cardiology, Department of Internal Medicine (S.Y.K., G.G.S., F.A., K.M.F., N.J., P.A.S., H.I.M., X.L., L.I.S., S.L., T.G.G., J.A.H.), University of Texas Southwestern, Dallas
| | - Joseph A Hill
- Division of Cardiology, Department of Internal Medicine (S.Y.K., G.G.S., F.A., K.M.F., N.J., P.A.S., H.I.M., X.L., L.I.S., S.L., T.G.G., J.A.H.), University of Texas Southwestern, Dallas
- Department of Molecular Biology (J.A.H.), University of Texas Southwestern, Dallas
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7
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Cardoso AC, Lam NT, Savla JJ, Nakada Y, Pereira AHM, Elnwasany A, Menendez-Montes I, Ensley EL, Petric UB, Sharma G, Sherry AD, Malloy CR, Khemtong C, Kinter MT, Tan WLW, Anene-Nzelu CG, Foo RSY, Nguyen NUN, Li S, Ahmed MS, Elhelaly WM, Abdisalaam S, Asaithamby A, Xing C, Kanchwala M, Vale G, Eckert KM, Mitsche MA, McDonald JG, Hill JA, Huang L, Shaul PW, Szweda LI, Sadek HA. Mitochondrial Substrate Utilization Regulates Cardiomyocyte Cell Cycle Progression. Nat Metab 2020; 2:167-178. [PMID: 32617517 PMCID: PMC7331943] [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] [Grants] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The neonatal mammalian heart is capable of regeneration for a brief window of time after birth. However, this regenerative capacity is lost within the first week of life, which coincides with a postnatal shift from anaerobic glycolysis to mitochondrial oxidative phosphorylation, particularly towards fatty-acid utilization. Despite the energy advantage of fatty-acid beta-oxidation, cardiac mitochondria produce elevated rates of reactive oxygen species when utilizing fatty acids, which is thought to play a role in cardiomyocyte cell-cycle arrest through induction of DNA damage and activation of DNA-damage response (DDR) pathway. Here we show that inhibiting fatty-acid utilization promotes cardiomyocyte proliferation in the postnatatal heart. First, neonatal mice fed fatty-acid deficient milk showed prolongation of the postnatal cardiomyocyte proliferative window, however cell cycle arrest eventually ensued. Next, we generated a tamoxifen-inducible cardiomyocyte-specific, pyruvate dehydrogenase kinase 4 (PDK4) knockout mouse model to selectively enhance oxidation of glycolytically derived pyruvate in cardiomyocytes. Conditional PDK4 deletion resulted in an increase in pyruvate dehydrogenase activity and consequently an increase in glucose relative to fatty-acid oxidation. Loss of PDK4 also resulted in decreased cardiomyocyte size, decreased DNA damage and expression of DDR markers and an increase in cardiomyocyte proliferation. Following myocardial infarction, inducible deletion of PDK4 improved left ventricular function and decreased remodelling. Collectively, inhibition of fatty-acid utilization in cardiomyocytes promotes proliferation, and may be a viable target for cardiac regenerative therapies.
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Affiliation(s)
- Alisson C. Cardoso
- Department of Internal Medicine, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
- Brazilian Biosciences National Laboratory, Brazilian Center
for Research in Energy and Materials (CNPEM), Campinas, Sao Paulo, Brazil
| | - Nicholas T. Lam
- Department of Internal Medicine, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
| | - Jainy J. Savla
- Department of Internal Medicine, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
| | - Yuji Nakada
- Department of Internal Medicine, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
| | - Ana Helena M. Pereira
- Department of Internal Medicine, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
- Brazilian Biosciences National Laboratory, Brazilian Center
for Research in Energy and Materials (CNPEM), Campinas, Sao Paulo, Brazil
| | - Abdallah Elnwasany
- Department of Internal Medicine, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
| | - Ivan Menendez-Montes
- Department of Internal Medicine, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
| | - Emily L. Ensley
- Department of Internal Medicine, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
| | - Ursa Bezan Petric
- Department of Internal Medicine, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
| | - Gaurav Sharma
- Advanced Imaging Research Center, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
| | - A. Dean Sherry
- Advanced Imaging Research Center, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
- Department of Radiology, University of Texas Southwestern
Medical Center, Dallas, Texas, USA
- Department of Chemistry, University of Texas in Dallas,
Dallas, Texas, USA
| | - Craig R. Malloy
- Department of Internal Medicine, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
- Advanced Imaging Research Center, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
- Department of Radiology, University of Texas Southwestern
Medical Center, Dallas, Texas, USA
| | - Chalermchai Khemtong
- Advanced Imaging Research Center, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
- Department of Radiology, University of Texas Southwestern
Medical Center, Dallas, Texas, USA
| | - Michael T. Kinter
- Aging and Metabolism Research Program, Oklahoma Medical
Research Foundation, Oklahoma City, Oklahoma, USA
| | - Wilson Lek Wen Tan
- Cardiovascular Research Institute, National University
Health Systems, Singapore, Genome Institute of Singapore, Singapore
| | - Chukwuemeka George Anene-Nzelu
- Cardiovascular Research Institute, National University
Health Systems, Singapore, Genome Institute of Singapore, Singapore
| | - Roger Sik-Yin Foo
- Cardiovascular Research Institute, National University
Health Systems, Singapore, Genome Institute of Singapore, Singapore
| | - Ngoc Uyen Nhi Nguyen
- Department of Internal Medicine, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
| | - Shujuan Li
- Department of Internal Medicine, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
- Department of Pediatric Cardiology, the First Affiliated
Hospital of Sun Yat-sen University, Guangzhou, China
- NHC Key Laboratory of Assisted Circulation (Sun Yat-sen
University), Guangzhou, China
| | - Mahmoud Salama Ahmed
- Department of Internal Medicine, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
| | - Waleed M. Elhelaly
- Department of Internal Medicine, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
| | - Salim Abdisalaam
- Department of Radiation Oncology, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
| | - Aroumougame Asaithamby
- Department of Radiation Oncology, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
| | - Chao Xing
- McDermontt Center for Human Growth and Development,
University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Mohammed Kanchwala
- McDermontt Center for Human Growth and Development,
University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Goncalo Vale
- Center for Human Nutrition, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
| | - Kaitlyn M. Eckert
- Center for Human Nutrition, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
| | - Matthew A Mitsche
- Center for Human Nutrition, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
| | - Jeffrey G. McDonald
- Center for Human Nutrition, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
- Department of Molecular Genetics, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
| | - Joseph A. Hill
- Department of Internal Medicine, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
| | - Linzhang Huang
- Center for Pulmonary and Vascular Biology, Department of
Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas,
USA
| | - Philip W. Shaul
- Center for Pulmonary and Vascular Biology, Department of
Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas,
USA
| | - Luke I. Szweda
- Department of Internal Medicine, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
| | - Hesham A. Sadek
- Department of Internal Medicine, University of Texas
Southwestern Medical Center, Dallas, Texas, USA
- Center for Regenerative Science and Medicine, University
of Texas Southwestern Medical Center, Dallas, Texas, USA
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8
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Peri-Okonny P, Baskin KK, Iwamoto G, Mitchell JH, Smith SA, Kim HK, Szweda LI, Bassel-Duby R, Fujikawa T, Castorena CM, Richardson J, Shelton JM, Ayers C, Berry JD, Malladi VS, Hu MC, Moe OW, Scherer PE, Vongpatanasin W. High-Phosphate Diet Induces Exercise Intolerance and Impairs Fatty Acid Metabolism in Mice. Circulation 2019; 139:1422-1434. [PMID: 30612451 DOI: 10.1161/circulationaha.118.037550] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [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] [Indexed: 01/14/2023]
Abstract
BACKGROUND Inorganic phosphate (Pi) is used extensively as a preservative and a flavor enhancer in the Western diet. Physical inactivity, a common feature of Western societies, is associated with increased cardiovascular morbidity and mortality. It is unknown whether dietary Pi excess contributes to exercise intolerance and physical inactivity. METHODS To determine an association between Pi excess and physical activity in humans, we assessed the relationship between serum Pi and actigraphy-determined physical activity level, as well as left ventricular function by cardiac magnetic resonance imaging, in DHS-2 (Dallas Heart Study phase 2) participants after adjusting for relevant variables. To determine direct effects of dietary Pi on exercise capacity, oxygen uptake, serum nonesterified fatty acid, and glucose were measured during exercise treadmill test in C57/BL6 mice fed either a high-Pi (2%) or normal-Pi (0.6%) diet for 12 weeks. To determine the direct effect of Pi on muscle metabolism and expression of genes involved in fatty acid metabolism, additional studies in differentiated C2C12 myotubes were conducted after subjecting to media containing 1 to 3 mmol/L Pi (pH 7.0) to simulate in vivo phosphate conditions. RESULTS In participants of the DHS-2 (n=1603), higher serum Pi was independently associated with reduced time spent in moderate to vigorous physical activity ( P=0.01) and increased sedentary time ( P=0.004). There was no association between serum Pi and left ventricular ejection fraction or volumes. In animal studies, compared with the control diet, consumption of high-Pi diet for 12 weeks did not alter body weight or left ventricular function but reduced maximal oxygen uptake, treadmill duration, spontaneous locomotor activity, fat oxidation, and fatty acid levels and led to downregulation of genes involved in fatty acid synthesis, release, and oxidation, including Fabp4, Hsl, Fasn, and Pparγ, in muscle. Similar results were recapitulated in vitro by incubating C2C12 myotubes with high-Pi media. CONCLUSIONS Our data demonstrate a detrimental effect of dietary Pi excess on skeletal muscle fatty acid metabolism and exercise capacity that is independent of obesity and cardiac contractile function. Dietary Pi may represent a novel and modifiable target to reduce physical inactivity associated with the Western diet.
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Affiliation(s)
- Poghni Peri-Okonny
- Department of Internal Medicine, Hypertension Section (P.P.-O., H.K.K., W.V.), University of Texas Southwestern Medical Center, Dallas
| | - Kedryn K Baskin
- Department of Molecular Biology (K.K.B., R.B.-D.), University of Texas Southwestern Medical Center, Dallas.,Dorothy M. Davis Heart and Lung Research Institute, Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus (K.K.B.)
| | - Gary Iwamoto
- Department of Cell Biology (G.I.), University of Texas Southwestern Medical Center, Dallas
| | - Jere H Mitchell
- Department of Internal Medicine, Cardiology Division (J.H.M., L.I.S., J.M.S., J.D.B., W.V.), University of Texas Southwestern Medical Center, Dallas
| | - Scott A Smith
- Department of Health Care Sciences (S.A.S.), University of Texas Southwestern Medical Center, Dallas
| | - Han Kyul Kim
- Department of Internal Medicine, Hypertension Section (P.P.-O., H.K.K., W.V.), University of Texas Southwestern Medical Center, Dallas
| | - Luke I Szweda
- Department of Internal Medicine, Cardiology Division (J.H.M., L.I.S., J.M.S., J.D.B., W.V.), University of Texas Southwestern Medical Center, Dallas
| | - Rhonda Bassel-Duby
- Department of Molecular Biology (K.K.B., R.B.-D.), University of Texas Southwestern Medical Center, Dallas
| | - Teppei Fujikawa
- Department of Cellular and Integrative Physiology, Long School of Medicine, University of Texas Health San Antonio (T.F.)
| | - Carlos M Castorena
- Department of Internal Medicine, Division of Hypothalamic Research (C.M.C.), University of Texas Southwestern Medical Center, Dallas
| | - James Richardson
- Department of Pathology (J.R.), University of Texas Southwestern Medical Center, Dallas
| | - John M Shelton
- Department of Internal Medicine, Cardiology Division (J.H.M., L.I.S., J.M.S., J.D.B., W.V.), University of Texas Southwestern Medical Center, Dallas
| | - Colby Ayers
- Department of Clinical Sciences (C.A., J.D.B.), University of Texas Southwestern Medical Center, Dallas
| | - Jarett D Berry
- Department of Internal Medicine, Cardiology Division (J.H.M., L.I.S., J.M.S., J.D.B., W.V.), University of Texas Southwestern Medical Center, Dallas.,Department of Clinical Sciences (C.A., J.D.B.), University of Texas Southwestern Medical Center, Dallas
| | - Venkat S Malladi
- Department of Bioinformatics (V.S.M.), University of Texas Southwestern Medical Center, Dallas
| | - Ming-Chang Hu
- Department of Internal Medicine, Division of Nephrology (M.-C.H., O.W.M.), University of Texas Southwestern Medical Center, Dallas.,Department of Physiology (M.-C.H., O.W.M.), University of Texas Southwestern Medical Center, Dallas.,Pak Center of Mineral Metabolism and Clinical Research (M.-C.H., O.W.M., W.V.), University of Texas Southwestern Medical Center, Dallas
| | - Orson W Moe
- Department of Internal Medicine, Division of Nephrology (M.-C.H., O.W.M.), University of Texas Southwestern Medical Center, Dallas.,Department of Physiology (M.-C.H., O.W.M.), University of Texas Southwestern Medical Center, Dallas.,Pak Center of Mineral Metabolism and Clinical Research (M.-C.H., O.W.M., W.V.), University of Texas Southwestern Medical Center, Dallas
| | - Philipp E Scherer
- Touchstone Diabetes Center (P.E.S.), University of Texas Southwestern Medical Center, Dallas
| | - Wanpen Vongpatanasin
- Department of Internal Medicine, Hypertension Section (P.P.-O., H.K.K., W.V.), University of Texas Southwestern Medical Center, Dallas.,Department of Internal Medicine, Cardiology Division (J.H.M., L.I.S., J.M.S., J.D.B., W.V.), University of Texas Southwestern Medical Center, Dallas.,Pak Center of Mineral Metabolism and Clinical Research (M.-C.H., O.W.M., W.V.), University of Texas Southwestern Medical Center, Dallas
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9
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Makarewich CA, Baskin KK, Munir AZ, Bezprozvannaya S, Sharma G, Khemtong C, Shah AM, McAnally JR, Malloy CR, Szweda LI, Bassel-Duby R, Olson EN. MOXI Is a Mitochondrial Micropeptide That Enhances Fatty Acid β-Oxidation. Cell Rep 2019; 23:3701-3709. [PMID: 29949755 PMCID: PMC6066340 DOI: 10.1016/j.celrep.2018.05.058] [Citation(s) in RCA: 102] [Impact Index Per Article: 20.4] [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: 01/02/2018] [Revised: 04/10/2018] [Accepted: 05/16/2018] [Indexed: 12/30/2022] Open
Abstract
Micropeptide regulator of β-oxidation (MOXI) is a conserved muscle-enriched protein encoded by an RNA transcript misannotated as non-coding. MOXI localizes to the inner mitochondrial membrane where it associates with the mitochondrial trifunctional protein, an enzyme complex that plays a critical role in fatty acid β-oxidation. Isolated heart and skeletal muscle mitochondria from MOXI knockout mice exhibit a diminished ability to metabolize fatty acids, while transgenic MOXI overexpression leads to enhanced β-oxidation. Additionally, hearts from MOXI knockout mice preferentially oxidize carbohydrates over fatty acids in an isolated perfused heart system compared to wild-type (WT) animals. MOXI knockout mice also exhibit a profound reduction in exercise capacity, highlighting the role of MOXI in metabolic control. The functional characterization of MOXI provides insight into the regulation of mitochondrial metabolism and energy homeostasis and underscores the regulatory potential of additional micropeptides that have yet to be identified. Micropeptide regulator of b-oxidation (MOXI) is encoded by a muscle-enriched RNA transcript misannotated as noncoding. MOXI localizes to the inner mitochondrial membrane where it interacts with the trifunctional protein to modulate fatty acid b-oxidation and exercise capacity.
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Affiliation(s)
- Catherine A Makarewich
- Department of Molecular Biology and the Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Kedryn K Baskin
- Department of Molecular Biology and the Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Amir Z Munir
- Department of Molecular Biology and the Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Svetlana Bezprozvannaya
- Department of Molecular Biology and the Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Gaurav Sharma
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Chalermchai Khemtong
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Akansha M Shah
- Department of Molecular Biology and the Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - John R McAnally
- Department of Molecular Biology and the Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Craig R Malloy
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Radiology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Luke I Szweda
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Rhonda Bassel-Duby
- Department of Molecular Biology and the Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Eric N Olson
- Department of Molecular Biology and the Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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10
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Newhardt MF, Batushansky A, Matsuzaki S, Young ZT, West M, Chin NC, Szweda LI, Kinter M, Humphries KM. Enhancing cardiac glycolysis causes an increase in PDK4 content in response to short-term high-fat diet. J Biol Chem 2019; 294:16831-16845. [PMID: 31562244 DOI: 10.1074/jbc.ra119.010371] [Citation(s) in RCA: 12] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2019] [Revised: 09/18/2019] [Indexed: 12/17/2022] Open
Abstract
The healthy heart has a dynamic capacity to respond and adapt to changes in nutrient availability. Metabolic inflexibility, such as occurs with diabetes, increases cardiac reliance on fatty acids to meet energetic demands, and this results in deleterious effects, including mitochondrial dysfunction, that contribute to pathophysiology. Enhancing glucose usage may mitigate metabolic inflexibility and be advantageous under such conditions. Here, we sought to identify how mitochondrial function and cardiac metabolism are affected in a transgenic mouse model of enhanced cardiac glycolysis (GlycoHi) basally and following a short-term (7-day) high-fat diet (HFD). GlycoHi mice constitutively express an active form of phosphofructokinase-2, resulting in elevated levels of the PFK-1 allosteric activator fructose 2,6-bisphosphate. We report that basally GlycoHi mitochondria exhibit augmented pyruvate-supported respiration relative to fatty acids. Nevertheless, both WT and GlycoHi mitochondria had a similar shift toward increased rates of fatty acid-supported respiration following HFD. Metabolic profiling by GC-MS revealed distinct features based on both genotype and diet, with a unique increase in branched-chain amino acids in the GlycoHi HFD group. Targeted quantitative proteomics analysis also supported both genotype- and diet-dependent changes in protein expression and uncovered an enhanced expression of pyruvate dehydrogenase kinase 4 (PDK4) in the GlycoHi HFD group. These results support a newly identified mechanism whereby the levels of fructose 2,6-bisphosphate promote mitochondrial PDK4 levels and identify a secondary adaptive response that prevents excessive mitochondrial pyruvate oxidation when glycolysis is sustained after a high-fat dietary challenge.
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Affiliation(s)
- Maria F Newhardt
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104.,Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104
| | - Albert Batushansky
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104
| | - Satoshi Matsuzaki
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104
| | - Zachary T Young
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104
| | - Melinda West
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104
| | - Ngun Cer Chin
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104
| | - Luke I Szweda
- Division of Cardiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-8573
| | - Michael Kinter
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104
| | - Kenneth M Humphries
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104 .,Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104
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11
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Tong D, Schiattarella GG, Jiang N, Altamirano F, Szweda PA, Elnwasany A, Lee DI, Szweda LI, Kass DA, Gillette TG, Hill JA. Abstract 867: NAD
+
Repletion Reverses HFpEF by Attenuating Myocardial Metabolic Dysfunction. Circ Res 2019. [DOI: 10.1161/res.125.suppl_1.867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background:
Heart failure with preserved ejection fraction (HFpEF) is a highly prevalent clinical condition associated with significant morbidity, mortality and health care expenses. Yet, no effective treatment has been identified. We recently demonstrated that concomitant metabolic and hypertensive stress in mice elicited by a combination of high fat diet (HFD) and constitutive nitric oxide synthase inhibition by N
[w]
-nitro-l-arginine methyl ester (L-NAME) faithfully recapitulates the numerous and myriad features of human HFpEF (paper in press at
Nature
).
Methods:
Wild type C57Bl6 mice were fed with HFD and L-NAME via drinking water for 5-8 weeks. Myocardial mitochondrial morphology was assessed by electron microscopy. Mitochondrial function was assessed by measuring oxygen consumption rates using an oxygen electrode. Protein expression and modification were assessed by Western blotting and immunoprecipitation.
Results:
Using this novel mouse model, we discovered significant impairment of mitochondrial fatty acid oxidation (FAO) associated with hyperacetylation of key FAO enzymes in HFpEF myocardium. Mechanistically, downregulation of Sirtuin3, the major mitochondrial deacetylase, and deficiency of its co-substrate nicotinamide adenine dinucleotide (NAD
+
), culminated in mitochondrial protein hyperacetylation. Strikingly, supplementation with nicotinamide riboside (NR), a NAD
+
precursor, led to dramatic improvement of mitochondrial function, and importantly, amelioration of the HFpEF phenotype.
Conclusion:
In summary, we have unveiled that protein hyperacetylation-mediated mitochondrial dysfunction is a crucial mechanism of HFpEF pathogenesis. This is, to our knowledge, the first study identifying a specific signature of metabolic remodeling in HFpEF heart. We also demonstrated the therapeutic effect of NAD
+
repletion in a preclinical HFpEF model. In next steps, confirming this benefit in a clinical trial is warranted.
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Affiliation(s)
- Dan Tong
- Univ of Texas Southwestern Med Cntr, Dallas, TX
| | | | - Nan Jiang
- Univ of Texas Southwestern Med Cntr, Dallas, TX
| | | | | | | | - Dong I Lee
- Johns Hopkins Sch of Medicine, Baltimore, MD
| | | | | | | | | |
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12
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Peri‐Okonny PA, Baskin KK, Iwamoto G, Mitchell JH, Smith SA, Kim HKA, Szweda LI, Bassel‐Duby R, Fujikawa T, Castro CM, Richardson J, Shelton JM, Ayers C, Berry JD, Malladi VS, Hu M, Moe OW, Scherer PE, Vongpatanasin W. High Phosphate Diet Induces Exercise Intolerance and Impairs Fatty Acid Metabolism in Mice. FASEB J 2019. [DOI: 10.1096/fasebj.2019.33.1_supplement.lb462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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13
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Hirose K, Payumo AY, Cutie S, Hoang A, Zhang H, Guyot R, Lunn D, Bigley RB, Yu H, Wang J, Smith M, Gillett E, Muroy SE, Schmid T, Wilson E, Field KA, Reeder DM, Maden M, Yartsev MM, Wolfgang MJ, Grützner F, Scanlan TS, Szweda LI, Buffenstein R, Hu G, Flamant F, Olgin JE, Huang GN. Evidence for hormonal control of heart regenerative capacity during endothermy acquisition. Science 2019; 364:184-188. [PMID: 30846611 DOI: 10.1126/science.aar2038] [Citation(s) in RCA: 213] [Impact Index Per Article: 42.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 11/15/2018] [Accepted: 02/21/2019] [Indexed: 12/11/2022]
Abstract
Tissue regenerative potential displays striking divergence across phylogeny and ontogeny, but the underlying mechanisms remain enigmatic. Loss of mammalian cardiac regenerative potential correlates with cardiomyocyte cell-cycle arrest and polyploidization as well as the development of postnatal endothermy. We reveal that diploid cardiomyocyte abundance across 41 species conforms to Kleiber's law-the ¾-power law scaling of metabolism with bodyweight-and inversely correlates with standard metabolic rate, body temperature, and serum thyroxine level. Inactivation of thyroid hormone signaling reduces mouse cardiomyocyte polyploidization, delays cell-cycle exit, and retains cardiac regenerative potential in adults. Conversely, exogenous thyroid hormones inhibit zebrafish heart regeneration. Thus, our findings suggest that loss of heart regenerative capacity in adult mammals is triggered by increasing thyroid hormones and may be a trade-off for the acquisition of endothermy.
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Affiliation(s)
- Kentaro Hirose
- Cardiovascular Research Institute and Department of Physiology, University of California, San Francisco, San Francisco, CA 94158, USA.,Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Alexander Y Payumo
- Cardiovascular Research Institute and Department of Physiology, University of California, San Francisco, San Francisco, CA 94158, USA.,Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Stephen Cutie
- Cardiovascular Research Institute and Department of Physiology, University of California, San Francisco, San Francisco, CA 94158, USA.,Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Alison Hoang
- Cardiovascular Research Institute and Department of Physiology, University of California, San Francisco, San Francisco, CA 94158, USA.,Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Hao Zhang
- Department of Medicine, Division of Cardiology, University of California San Francisco, San Francisco, CA 94158, USA
| | - Romain Guyot
- Department of Internal Medicine, Institut de Génomique Fonctionnelle de Lyon, Institut National de la Recherche Agronomique, Université Lyon 1, CNRS, École Normale Superieure de Lyon, 69 007 France
| | - Dominic Lunn
- Cardiovascular Research Institute and Department of Physiology, University of California, San Francisco, San Francisco, CA 94158, USA.,Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Rachel B Bigley
- Cardiovascular Research Institute and Department of Physiology, University of California, San Francisco, San Francisco, CA 94158, USA.,Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Hongyao Yu
- Epigenetics and Stem Cell Biology Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
| | - Jiajia Wang
- Epigenetics and Stem Cell Biology Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
| | - Megan Smith
- Calico Life Sciences, 1170 Veterans Boulevard, South San Francisco, CA 94080, USA
| | - Ellen Gillett
- School of Biological Sciences, University of Adelaide, South Australia, Adelaide 5005, Australia
| | - Sandra E Muroy
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94708, USA
| | - Tobias Schmid
- Helen Wills Neuroscience Institute and Department of Bioengineering, University of California, Berkeley, Berkeley, CA 94708, USA
| | - Emily Wilson
- Department of Medicine, Division of Cardiology, University of California San Francisco, San Francisco, CA 94158, USA
| | - Kenneth A Field
- Department of Biology, Bucknell University, Lewisburg, PA 17837, USA
| | - DeeAnn M Reeder
- Department of Biology, Bucknell University, Lewisburg, PA 17837, USA
| | - Malcom Maden
- Department of Biology and UF Genetics Institute, University of Florida, Gainesville, FL 32611, USA
| | - Michael M Yartsev
- Helen Wills Neuroscience Institute and Department of Bioengineering, University of California, Berkeley, Berkeley, CA 94708, USA
| | - Michael J Wolfgang
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Frank Grützner
- School of Biological Sciences, University of Adelaide, South Australia, Adelaide 5005, Australia
| | - Thomas S Scanlan
- Department of Physiology and Pharmacology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
| | - Luke I Szweda
- Division of Cardiology, University of Texas Southwestern Medical Center, Dallas, TX 75390-8573, USA
| | - Rochelle Buffenstein
- Calico Life Sciences, 1170 Veterans Boulevard, South San Francisco, CA 94080, USA
| | - Guang Hu
- Epigenetics and Stem Cell Biology Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
| | - Frederic Flamant
- Department of Internal Medicine, Institut de Génomique Fonctionnelle de Lyon, Institut National de la Recherche Agronomique, Université Lyon 1, CNRS, École Normale Superieure de Lyon, 69 007 France
| | - Jeffrey E Olgin
- Cardiovascular Research Institute and Department of Physiology, University of California, San Francisco, San Francisco, CA 94158, USA.,Department of Medicine, Division of Cardiology, University of California San Francisco, San Francisco, CA 94158, USA
| | - Guo N Huang
- Cardiovascular Research Institute and Department of Physiology, University of California, San Francisco, San Francisco, CA 94158, USA. .,Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA 94158, USA
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14
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Schafer C, Young ZT, Makarewich CA, Elnwasany A, Kinter C, Kinter M, Szweda LI. Coenzyme A-mediated degradation of pyruvate dehydrogenase kinase 4 promotes cardiac metabolic flexibility after high-fat feeding in mice. J Biol Chem 2018. [PMID: 29540486 DOI: 10.1074/jbc.ra117.000268] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Cardiac energy is produced primarily by oxidation of fatty acids and glucose, with the relative contributions of each nutrient being sensitive to changes in substrate availability and energetic demand. A major contributor to cardiac metabolic flexibility is pyruvate dehydrogenase (PDH), which converts glucose-derived pyruvate to acetyl-CoA within the mitochondria. PDH is inhibited by phosphorylation dependent on the competing activities of pyruvate dehydrogenase kinases (PDK1-4) and phosphatases (PDP1-2). A single high-fat meal increases cardiac PDK4 content and subsequently inhibits PDH activity, reducing pyruvate utilization when abundant fatty acids are available. In this study, we demonstrate that diet-induced increases in PDK4 are reversible and characterize a novel pathway that regulates PDK4 degradation in response to the cardiac metabolic environment. We found that PDK4 degradation is promoted by CoA (CoASH), the levels of which declined in mice fed a high-fat diet and normalized following transition to a control diet. We conclude that CoASH functions as a metabolic sensor linking the rate of PDK4 degradation to fatty acid availability in the heart. However, prolonged high-fat feeding followed by return to a low-fat diet resulted in persistent in vitro sensitivity of PDH to fatty acid-induced inhibition despite reductions in PDK4 content. Moreover, increases in the levels of proteins responsible for β-oxidation and rates of palmitate oxidation by isolated cardiac mitochondria following long-term consumption of high dietary fat persisted after transition to the control diet. We propose that these changes prime PDH for inhibition upon reintroduction of fatty acids.
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Affiliation(s)
- Christopher Schafer
- From the Aging and Metabolism Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104
| | - Zachary T Young
- From the Aging and Metabolism Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104
| | - Catherine A Makarewich
- the Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, and
| | - Abdallah Elnwasany
- the Department of Internal Medicine, Division of Cardiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-8573
| | - Caroline Kinter
- From the Aging and Metabolism Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104
| | - Michael Kinter
- From the Aging and Metabolism Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104
| | - Luke I Szweda
- From the Aging and Metabolism Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104, .,the Department of Internal Medicine, Division of Cardiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-8573
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15
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Logan S, Pharaoh GA, Marlin MC, Masser DR, Matsuzaki S, Wronowski B, Yeganeh A, Parks EE, Premkumar P, Farley JA, Owen DB, Humphries KM, Kinter M, Freeman WM, Szweda LI, Van Remmen H, Sonntag WE. Insulin-like growth factor receptor signaling regulates working memory, mitochondrial metabolism, and amyloid-β uptake in astrocytes. Mol Metab 2018; 9:141-155. [PMID: 29398615 PMCID: PMC5870102 DOI: 10.1016/j.molmet.2018.01.013] [Citation(s) in RCA: 107] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 01/11/2018] [Accepted: 01/16/2018] [Indexed: 01/01/2023] Open
Abstract
Objective A decline in mitochondrial function and biogenesis as well as increased reactive oxygen species (ROS) are important determinants of aging. With advancing age, there is a concomitant reduction in circulating levels of insulin-like growth factor-1 (IGF-1) that is closely associated with neuronal aging and neurodegeneration. In this study, we investigated the effect of the decline in IGF-1 signaling with age on astrocyte mitochondrial metabolism and astrocyte function and its association with learning and memory. Methods Learning and memory was assessed using the radial arm water maze in young and old mice as well as tamoxifen-inducible astrocyte-specific knockout of IGFR (GFAP-CreTAM/igfrf/f). The impact of IGF-1 signaling on mitochondrial function was evaluated using primary astrocyte cultures from igfrf/f mice using AAV-Cre mediated knockdown using Oroboros respirometry and Seahorse assays. Results Our results indicate that a reduction in IGF-1 receptor (IGFR) expression with age is associated with decline in hippocampal-dependent learning and increased gliosis. Astrocyte-specific knockout of IGFR also induced impairments in working memory. Using primary astrocyte cultures, we show that reducing IGF-1 signaling via a 30–50% reduction IGFR expression, comparable to the physiological changes in IGF-1 that occur with age, significantly impaired ATP synthesis. IGFR deficient astrocytes also displayed altered mitochondrial structure and function and increased mitochondrial ROS production associated with the induction of an antioxidant response. However, IGFR deficient astrocytes were more sensitive to H2O2-induced cytotoxicity. Moreover, IGFR deficient astrocytes also showed significantly impaired glucose and Aβ uptake, both critical functions of astrocytes in the brain. Conclusions Regulation of astrocytic mitochondrial function and redox status by IGF-1 is essential to maintain astrocytic function and coordinate hippocampal-dependent spatial learning. Age-related astrocytic dysfunction caused by diminished IGF-1 signaling may contribute to the pathogenesis of Alzheimer's disease and other age-associated cognitive pathologies. Altered mitochondrial structure and function with IGFR deficiency in astrocytes is proposed. Increased reactive oxygen species production and susceptibility to peroxide induced cytotoxicity. Decreased Aβ uptake and impairment in spatial working memory.
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Affiliation(s)
- Sreemathi Logan
- Reynold's Oklahoma Center on Aging, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center, USA.
| | - Gavin A Pharaoh
- Department of Physiology, University of Oklahoma Health Sciences Center, USA; Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, USA
| | - M Caleb Marlin
- Graduate College, University of Oklahoma Health Sciences Center, USA
| | - Dustin R Masser
- Reynold's Oklahoma Center on Aging, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center, USA; Department of Physiology, University of Oklahoma Health Sciences Center, USA
| | - Satoshi Matsuzaki
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, USA; Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, USA
| | - Benjamin Wronowski
- Reynold's Oklahoma Center on Aging, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center, USA; Department of Physiology, University of Oklahoma Health Sciences Center, USA
| | - Alexander Yeganeh
- Reynold's Oklahoma Center on Aging, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center, USA; Oklahoma Center for Neuroscience, University of Oklahoma Health Sciences Center, USA
| | - Eileen E Parks
- Reynold's Oklahoma Center on Aging, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center, USA; Oklahoma Center for Neuroscience, University of Oklahoma Health Sciences Center, USA
| | - Pavithra Premkumar
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, USA
| | - Julie A Farley
- Reynold's Oklahoma Center on Aging, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center, USA
| | - Daniel B Owen
- Reynold's Oklahoma Center on Aging, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center, USA
| | - Kenneth M Humphries
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, USA; Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, USA
| | - Michael Kinter
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, USA
| | - Willard M Freeman
- Reynold's Oklahoma Center on Aging, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center, USA; Department of Physiology, University of Oklahoma Health Sciences Center, USA; Oklahoma Center for Neuroscience, University of Oklahoma Health Sciences Center, USA
| | - Luke I Szweda
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, USA; Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, USA
| | - Holly Van Remmen
- Department of Physiology, University of Oklahoma Health Sciences Center, USA; Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, USA; Oklahoma Center for Neuroscience, University of Oklahoma Health Sciences Center, USA
| | - William E Sonntag
- Reynold's Oklahoma Center on Aging, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center, USA; Department of Physiology, University of Oklahoma Health Sciences Center, USA; Oklahoma Center for Neuroscience, University of Oklahoma Health Sciences Center, USA
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16
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Pearsall EA, Cheng R, Zhou K, Takahashi Y, Matlock HG, Vadvalkar SS, Shin Y, Fredrick TW, Gantner ML, Meng S, Fu Z, Gong Y, Kinter M, Humphries KM, Szweda LI, Smith LEH, Ma JX. PPARα is essential for retinal lipid metabolism and neuronal survival. BMC Biol 2017; 15:113. [PMID: 29183319 PMCID: PMC5706156 DOI: 10.1186/s12915-017-0451-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [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: 06/03/2017] [Accepted: 11/06/2017] [Indexed: 11/29/2022] Open
Abstract
Background Peroxisome proliferator activated receptor-alpha (PPARα) is a ubiquitously expressed nuclear receptor. The role of endogenous PPARα in retinal neuronal homeostasis is unknown. Retinal photoreceptors are the highest energy-consuming cells in the body, requiring abundant energy substrates. PPARα is a known regulator of lipid metabolism, and we hypothesized that it may regulate lipid use for oxidative phosphorylation in energetically demanding retinal neurons. Results We found that endogenous PPARα is essential for the maintenance and survival of retinal neurons, with Pparα-/- mice developing retinal degeneration first detected at 8 weeks of age. Using extracellular flux analysis, we identified that PPARα mediates retinal utilization of lipids as an energy substrate, and that ablation of PPARα ultimately results in retinal bioenergetic deficiency and neurodegeneration. This may be due to PPARα regulation of lipid transporters, which facilitate the internalization of fatty acids into cell membranes and mitochondria for oxidation and ATP production. Conclusion We identify an endogenous role for PPARα in retinal neuronal survival and lipid metabolism, and furthermore underscore the importance of fatty acid oxidation in photoreceptor survival. We also suggest PPARα as a putative therapeutic target for age-related macular degeneration, which may be due in part to decreased mitochondrial efficiency and subsequent energetic deficits. Electronic supplementary material The online version of this article (doi:10.1186/s12915-017-0451-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Elizabeth A Pearsall
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA.,Department of Physiology, University of Oklahoma Health Sciences Center, 941 Stanton L. Young Blvd., BSEB 328B, Oklahoma City, OK, 73104, USA
| | - Rui Cheng
- Department of Physiology, University of Oklahoma Health Sciences Center, 941 Stanton L. Young Blvd., BSEB 328B, Oklahoma City, OK, 73104, USA
| | - Kelu Zhou
- Department of Physiology, University of Oklahoma Health Sciences Center, 941 Stanton L. Young Blvd., BSEB 328B, Oklahoma City, OK, 73104, USA
| | - Yusuke Takahashi
- Department of Physiology, University of Oklahoma Health Sciences Center, 941 Stanton L. Young Blvd., BSEB 328B, Oklahoma City, OK, 73104, USA.,Section of Diabetes and Endocrinology, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK, 73104, USA
| | - H Greg Matlock
- Department of Physiology, University of Oklahoma Health Sciences Center, 941 Stanton L. Young Blvd., BSEB 328B, Oklahoma City, OK, 73104, USA
| | - Shraddha S Vadvalkar
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | - Younghwa Shin
- Department of Physiology, University of Oklahoma Health Sciences Center, 941 Stanton L. Young Blvd., BSEB 328B, Oklahoma City, OK, 73104, USA
| | - Thomas W Fredrick
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Marin L Gantner
- The Lowy Medical Research Institute, La Jolla, CA, 92037, USA
| | - Steven Meng
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Zhongjie Fu
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Yan Gong
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Michael Kinter
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | - Kenneth M Humphries
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | - Luke I Szweda
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | - Lois E H Smith
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Jian-Xing Ma
- Department of Physiology, University of Oklahoma Health Sciences Center, 941 Stanton L. Young Blvd., BSEB 328B, Oklahoma City, OK, 73104, USA. .,Section of Diabetes and Endocrinology, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK, 73104, USA.
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17
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Jackson RM, Griesel BA, Gurley JM, Szweda LI, Olson AL. Glucose availability controls adipogenesis in mouse 3T3-L1 adipocytes via up-regulation of nicotinamide metabolism. J Biol Chem 2017; 292:18556-18564. [PMID: 28916720 DOI: 10.1074/jbc.m117.791970] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [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: 04/18/2017] [Revised: 09/13/2017] [Indexed: 12/21/2022] Open
Abstract
Expansion of adipose tissue in response to a positive energy balance underlies obesity and occurs through both hypertrophy of existing cells and increased differentiation of adipocyte precursors (hyperplasia). To better understand the nutrient signals that promote adipocyte differentiation, we investigated the role of glucose availability in regulating adipocyte differentiation and maturation. 3T3-L1 preadipocytes were grown and differentiated in medium containing a standard differentiation hormone mixture and either 4 or 25 mm glucose. Adipocyte maturation at day 9 post-differentiation was determined by key adipocyte markers, including glucose transporter 4 (GLUT4) and adiponectin expression and Oil Red O staining of neutral lipids. We found that adipocyte differentiation and maturation required a pulse of 25 mm glucose only during the first 3 days of differentiation. Importantly, fatty acids were unable to substitute for the 25 mm glucose pulse during this period. The 25 mm glucose pulse increased adiponectin and GLUT4 expression and accumulation of neutral lipids via distinct mechanisms. Adiponectin expression and other early markers of differentiation required an increase in the intracellular pool of total NAD/P. In contrast, GLUT4 protein expression was only partially restored by increased NAD/P levels. Furthermore, GLUT4 mRNA expression was mediated by glucose-dependent activation of GLUT4 gene transcription through the cis-acting GLUT4-liver X receptor element (LXRE) promoter element. In summary, this study supports the conclusion that high glucose promotes adipocyte differentiation via distinct metabolic pathways and independently of fatty acids. This may partly explain the mechanism underlying adipocyte hyperplasia that occurs much later than adipocyte hypertrophy in the development of obesity.
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Affiliation(s)
- Robert M Jackson
- From the Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104 and
| | - Beth A Griesel
- From the Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104 and
| | - Jami M Gurley
- From the Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104 and
| | - Luke I Szweda
- From the Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104 and.,the Program in Aging and Metabolism, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104
| | - Ann Louise Olson
- the Program in Aging and Metabolism, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104
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18
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Zahra A, Fath MA, Opat E, Mapuskar KA, Bhatia SK, Ma DC, Rodman SN, Snyders TP, Chenard CA, Eichenberger-Gilmore JM, Bodeker KL, Ahmann L, Smith BJ, Vollstedt SA, Brown HA, Hejleh TA, Clamon GH, Berg DJ, Szweda LI, Spitz DR, Buatti JM, Allen BG. Consuming a Ketogenic Diet while Receiving Radiation and Chemotherapy for Locally Advanced Lung Cancer and Pancreatic Cancer: The University of Iowa Experience of Two Phase 1 Clinical Trials. Radiat Res 2017; 187:743-754. [PMID: 28437190 DOI: 10.1667/rr14668.1] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Ketogenic diets are low in carbohydrates and high in fat, which forces cells to rely more heavily upon mitochondrial oxidation of fatty acids for energy. Relative to normal cells, cancer cells are believed to exist under a condition of chronic mitochondrial oxidative stress that is compensated for by increases in glucose metabolism to generate reducing equivalents. In this study we tested the hypothesis that a ketogenic diet concurrent with radiation and chemotherapy would be clinically tolerable in locally advanced non-small cell lung cancer (NSCLC) and pancreatic cancer and could potentially exploit cancer cell oxidative metabolism to improve therapeutic outcomes. Mice bearing MIA PaCa-2 pancreatic cancer xenografts were fed either a ketogenic diet or standard rodent chow, treated with conventionally fractionated radiation (2 Gy/fraction), and tumor growth rates were assessed daily. Tumors were assessed for immunoreactive 4-hydroxy-2-nonenal-(4HNE)-modfied proteins as a marker of oxidative stress. Based on this and another previously published preclinical study, phase 1 clinical trials in locally advanced NSCLC and pancreatic cancer were initiated, combining standard radiation and chemotherapy with a ketogenic diet for six weeks (NSCLC) or five weeks (pancreatic cancer). The xenograft experiments demonstrated prolonged survival and increased 4HNE-modfied proteins in animals consuming a ketogenic diet combined with radiation compared to radiation alone. In the phase 1 clinical trial, over a period of three years, seven NSCLC patients enrolled in the study. Of these, four were unable to comply with the diet and withdrew, two completed the study and one was withdrawn due to a dose-limiting toxicity. Over the same time period, two pancreatic cancer patients enrolled in the trial. Of these, one completed the study and the other was withdrawn due to a dose-limiting toxicity. The preclinical experiments demonstrate that a ketogenic diet increases radiation sensitivity in a pancreatic cancer xenograft model. However, patients with locally advanced NSCLC and pancreatic cancer receiving concurrent radiotherapy and chemotherapy had suboptimal compliance to the oral ketogenic diet and thus, poor tolerance.
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Affiliation(s)
- Amir Zahra
- a Department of Radiation Oncology, University of Iowa, Iowa City, Iowa 52242
| | - Melissa A Fath
- a Department of Radiation Oncology, University of Iowa, Iowa City, Iowa 52242
| | - Emyleigh Opat
- a Department of Radiation Oncology, University of Iowa, Iowa City, Iowa 52242
| | - Kranti A Mapuskar
- a Department of Radiation Oncology, University of Iowa, Iowa City, Iowa 52242
| | - Sudershan K Bhatia
- a Department of Radiation Oncology, University of Iowa, Iowa City, Iowa 52242
| | - Daniel C Ma
- a Department of Radiation Oncology, University of Iowa, Iowa City, Iowa 52242
| | - Samuel N Rodman
- a Department of Radiation Oncology, University of Iowa, Iowa City, Iowa 52242
| | - Travis P Snyders
- a Department of Radiation Oncology, University of Iowa, Iowa City, Iowa 52242
| | - Catherine A Chenard
- b Department of Internal Medicine, University of Iowa, Iowa City, Iowa 52242
| | | | - Kellie L Bodeker
- a Department of Radiation Oncology, University of Iowa, Iowa City, Iowa 52242
| | - Logan Ahmann
- a Department of Radiation Oncology, University of Iowa, Iowa City, Iowa 52242
| | - Brian J Smith
- d Holden Comprehensive Cancer Center, University of Iowa, Iowa City, Iowa 52242
| | - Sandy A Vollstedt
- a Department of Radiation Oncology, University of Iowa, Iowa City, Iowa 52242
| | - Heather A Brown
- a Department of Radiation Oncology, University of Iowa, Iowa City, Iowa 52242
| | - Taher Abu Hejleh
- e Division of Hematology and Oncology in the Department of Internal Medicine, University of Iowa, Iowa City, Iowa 52242
| | - Gerald H Clamon
- e Division of Hematology and Oncology in the Department of Internal Medicine, University of Iowa, Iowa City, Iowa 52242
| | - Daniel J Berg
- e Division of Hematology and Oncology in the Department of Internal Medicine, University of Iowa, Iowa City, Iowa 52242
| | - Luke I Szweda
- f Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104
| | - Douglas R Spitz
- a Department of Radiation Oncology, University of Iowa, Iowa City, Iowa 52242
| | - John M Buatti
- a Department of Radiation Oncology, University of Iowa, Iowa City, Iowa 52242
| | - Bryan G Allen
- a Department of Radiation Oncology, University of Iowa, Iowa City, Iowa 52242
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19
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Crewe C, Schafer C, Lee I, Kinter M, Szweda LI. Regulation of Pyruvate Dehydrogenase Kinase 4 in the Heart through Degradation by the Lon Protease in Response to Mitochondrial Substrate Availability. J Biol Chem 2016; 292:305-312. [PMID: 27856638 DOI: 10.1074/jbc.m116.754127] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [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: 08/16/2016] [Revised: 11/07/2016] [Indexed: 12/31/2022] Open
Abstract
Cardiac metabolic inflexibility is driven by robust up-regulation of pyruvate dehydrogenase kinase 4 (PDK4) and phosphorylation-dependent inhibition of pyruvate dehydrogenase (PDH) within a single day of feeding mice a high fat diet. In the current study, we have discovered that PDK4 is a short lived protein (t½ ∼ 1 h) and is specifically degraded by the mitochondrial protease Lon. Lon does not rapidly degrade PDK1 and -2, indicating specificity toward the PDK isoform that is a potent modulator of metabolic flexibility. Moreover, PDK4 degradation appears regulated by dissociation from the PDH complex dependent on the respiratory state and energetic substrate availability of mouse heart mitochondria. Finally, we demonstrate that pharmacologic inhibition of PDK4 promotes PDK4 degradation in vitro and in vivo These findings reveal a novel strategy to manipulate PDH activity by selectively targeting PDK4 content through dissociation and proteolysis.
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Affiliation(s)
- Clair Crewe
- From the Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104.,the Department of Biochemistry and Molecular Biology, University of Oklahoma Health Science Center, Oklahoma City, Oklahoma 73104, and
| | - Christopher Schafer
- From the Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104
| | - Irene Lee
- the Department of Chemistry, Case Western Reserve University, Cleveland, Ohio 44106
| | - Michael Kinter
- From the Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104
| | - Luke I Szweda
- From the Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104, .,the Department of Biochemistry and Molecular Biology, University of Oklahoma Health Science Center, Oklahoma City, Oklahoma 73104, and
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20
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Nakada Y, Canseco DC, Thet S, Abdisalaam S, Asaithamby A, Santos CX, Shah AM, Zhang H, Faber JE, Kinter MT, Szweda LI, Xing C, Hu Z, Deberardinis RJ, Schiattarella G, Hill JA, Oz O, Lu Z, Zhang CC, Kimura W, Sadek HA. Hypoxia induces heart regeneration in adult mice. Nature 2016; 541:222-227. [DOI: 10.1038/nature20173] [Citation(s) in RCA: 439] [Impact Index Per Article: 54.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 10/21/2016] [Indexed: 01/08/2023]
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21
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Rindler PM, Cacciola A, Kinter M, Szweda LI. Catalase-dependent H2O2 consumption by cardiac mitochondria and redox-mediated loss in insulin signaling. Am J Physiol Heart Circ Physiol 2016; 311:H1091-H1096. [PMID: 27614223 DOI: 10.1152/ajpheart.00066.2016] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 09/01/2016] [Indexed: 12/23/2022]
Abstract
We have recently demonstrated that catalase content in mouse cardiac mitochondria is selectively elevated in response to high dietary fat, a nutritional state associated with oxidative stress and loss in insulin signaling. Catalase and various isoforms of glutathione peroxidase and peroxiredoxin each catalyze the consumption of H2O2 Catalase, located primarily within peroxisomes and to a lesser extent mitochondria, has a low binding affinity for H2O2 relative to glutathione peroxidase and peroxiredoxin. As such, the contribution of catalase to mitochondrial H2O2 consumption is not well understood. In the current study, using highly purified cardiac mitochondria challenged with micromolar concentrations of H2O2, we found that catalase contributes significantly to mitochondrial H2O2 consumption. In addition, catalase is solely responsible for removal of H2O2 in nonrespiring or structurally disrupted mitochondria. Finally, in mice fed a high-fat diet, mitochondrial-derived H2O2 is responsible for diminished insulin signaling in the heart as evidenced by reduced insulin-stimulated Akt phosphorylation. While elevated mitochondrial catalase content (∼50%) enhanced the capacity of mitochondria to consume H2O2 in response to high dietary fat, the selective increase in catalase did not prevent H2O2-induced loss in cardiac insulin signaling. Taken together, our results indicate that mitochondrial catalase likely functions to preclude the formation of high levels of H2O2 without perturbing redox-dependent signaling.
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Affiliation(s)
- Paul M Rindler
- Affiliation: Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
| | - Angela Cacciola
- Affiliation: Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
| | - Michael Kinter
- Affiliation: Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
| | - Luke I Szweda
- Affiliation: Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
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22
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James KL, Ríos-Hernández LA, Wofford NQ, Mouttaki H, Sieber JR, Sheik CS, Nguyen HH, Yang Y, Xie Y, Erde J, Rohlin L, Karr EA, Loo JA, Ogorzalek Loo RR, Hurst GB, Gunsalus RP, Szweda LI, McInerney MJ. Pyrophosphate-Dependent ATP Formation from Acetyl Coenzyme A in Syntrophus aciditrophicus, a New Twist on ATP Formation. mBio 2016; 7:e01208-16. [PMID: 27531911 PMCID: PMC4992975 DOI: 10.1128/mbio.01208-16] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [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] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Accepted: 07/12/2016] [Indexed: 11/29/2022] Open
Abstract
UNLABELLED Syntrophus aciditrophicus is a model syntrophic bacterium that degrades key intermediates in anaerobic decomposition, such as benzoate, cyclohexane-1-carboxylate, and certain fatty acids, to acetate when grown with hydrogen-/formate-consuming microorganisms. ATP formation coupled to acetate production is the main source for energy conservation by S. aciditrophicus However, the absence of homologs for phosphate acetyltransferase and acetate kinase in the genome of S. aciditrophicus leaves it unclear as to how ATP is formed, as most fermentative bacteria rely on these two enzymes to synthesize ATP from acetyl coenzyme A (CoA) and phosphate. Here, we combine transcriptomic, proteomic, metabolite, and enzymatic approaches to show that S. aciditrophicus uses AMP-forming, acetyl-CoA synthetase (Acs1) for ATP synthesis from acetyl-CoA. acs1 mRNA and Acs1 were abundant in transcriptomes and proteomes, respectively, of S. aciditrophicus grown in pure culture and coculture. Cell extracts of S. aciditrophicus had low or undetectable acetate kinase and phosphate acetyltransferase activities but had high acetyl-CoA synthetase activity under all growth conditions tested. Both Acs1 purified from S. aciditrophicus and recombinantly produced Acs1 catalyzed ATP and acetate formation from acetyl-CoA, AMP, and pyrophosphate. High pyrophosphate levels and a high AMP-to-ATP ratio (5.9 ± 1.4) in S. aciditrophicus cells support the operation of Acs1 in the acetate-forming direction. Thus, S. aciditrophicus has a unique approach to conserve energy involving pyrophosphate, AMP, acetyl-CoA, and an AMP-forming, acetyl-CoA synthetase. IMPORTANCE Bacteria use two enzymes, phosphate acetyltransferase and acetate kinase, to make ATP from acetyl-CoA, while acetate-forming archaea use a single enzyme, an ADP-forming, acetyl-CoA synthetase, to synthesize ATP and acetate from acetyl-CoA. Syntrophus aciditrophicus apparently relies on a different approach to conserve energy during acetyl-CoA metabolism, as its genome does not have homologs to the genes for phosphate acetyltransferase and acetate kinase. Here, we show that S. aciditrophicus uses an alternative approach, an AMP-forming, acetyl-CoA synthetase, to make ATP from acetyl-CoA. AMP-forming, acetyl-CoA synthetases were previously thought to function only in the activation of acetate to acetyl-CoA.
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Affiliation(s)
- Kimberly L James
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma, USA
| | - Luis A Ríos-Hernández
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma, USA
| | - Neil Q Wofford
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma, USA
| | - Housna Mouttaki
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma, USA
| | - Jessica R Sieber
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma, USA
| | - Cody S Sheik
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma, USA
| | - Hong H Nguyen
- Department of Biological Chemistry, University of California Los Angeles, Los Angeles, California, USA
| | - Yanan Yang
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, California, USA
| | - Yongming Xie
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, California, USA
| | - Jonathan Erde
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, California, USA
| | - Lars Rohlin
- Department of Microbiology, Immunology and Molecular Genetics, University of California Los Angeles, Los Angeles, California, USA
| | - Elizabeth A Karr
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma, USA
| | - Joseph A Loo
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, California, USA Department of Biological Chemistry, University of California Los Angeles, Los Angeles, California, USA
| | - Rachel R Ogorzalek Loo
- Department of Biological Chemistry, University of California Los Angeles, Los Angeles, California, USA
| | - Gregory B Hurst
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Robert P Gunsalus
- Department of Microbiology, Immunology and Molecular Genetics, University of California Los Angeles, Los Angeles, California, USA
| | - Luke I Szweda
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - Michael J McInerney
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma, USA
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23
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Chaiswing L, Cole MP, St Clair DK, Ittarat W, Szweda LI, Oberley TD. Oxidative Damage Precedes Nitrative Damage in Adriamycin-Induced Cardiac Mitochondrial Injury. Toxicol Pathol 2016; 32:536-47. [PMID: 15605432 DOI: 10.1080/01926230490502601] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The purpose of the present study was to determine if elevated reactive oxygen (ROS)/nitrogen species (RNS) reported to be present in adriamycin (ADR)-induced cardiotoxicity actually resulted in cardiomyocyte oxidative/nitrative damage, and to quantitatively determine the time course and subcellular localization of these postulated damage products using an in vivo approach. B6C3 mice were treated with a single dose of 20 mg/kg ADR. Ultrastructural damage and levels of 4-hydroxy-2-nonenal (4HNE)-protein adducts and 3-nitrotyrosine (3NT) were analyzed. Quantitative ultrastructural damage using computerized image techniques showed cardiomyocyte injury as early as 3 hours, with mitochondria being the most extensively and progressively injured subcellular organelle. Analysis of 4HNE protein adducts by immunogold electron microscopy showed appearance of 4HNE protein adducts in mitochondria as early as 3 hours, with a peak at 6 hours and subsequent decline at 24 hours. 3NT levels were significantly increased in all subcellular compartments at 6 hours and subsequently declined at 24 hours. Our data showed ADR induced 4HNE-protein adducts in mitochondria at the same time point as when mitochondrial injury initially appeared. These results document for the first time in vivo that mitochondrial oxidative damage precedes nitrative damage. The progressive nature of mitochondrial injury suggests that mitochondria, not other subcellular organelles, are the major site of intracellular injury.
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Affiliation(s)
- Luksana Chaiswing
- Department of Pathology and Laboratory Medicine, William S. Middleton Memorial Veterans Administration Hospital and University of Wisconsin Medical School, Madison WI 53705, USA
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24
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Griffin TM, Humphries KM, Kinter M, Lim HY, Szweda LI. Nutrient sensing and utilization: Getting to the heart of metabolic flexibility. Biochimie 2015; 124:74-83. [PMID: 26476002 DOI: 10.1016/j.biochi.2015.10.013] [Citation(s) in RCA: 26] [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] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 10/12/2015] [Indexed: 02/07/2023]
Abstract
A central feature of obesity-related cardiometabolic diseases is the impaired ability to transition between fatty acid and glucose metabolism. This impairment, referred to as "metabolic inflexibility", occurs in a number of tissues, including the heart. Although the heart normally prefers to metabolize fatty acids over glucose, the inability to upregulate glucose metabolism under energetically demanding conditions contributes to a pathological state involving energy imbalance, impaired contractility, and post-translational protein modifications. This review discusses pathophysiologic processes that contribute to cardiac metabolic inflexibility and speculates on the potential physiologic origins that lead to the current state of cardiometabolic disease in an obesogenic environment.
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Affiliation(s)
- Timothy M Griffin
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA; Department of Geriatric Medicine, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
| | - Kenneth M Humphries
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA; Department of Geriatric Medicine, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
| | - Michael Kinter
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA; Department of Geriatric Medicine, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
| | - Hui-Ying Lim
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA; Department of Geriatric Medicine, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
| | - Luke I Szweda
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA; Department of Geriatric Medicine, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
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25
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Fernandes J, Weddle A, Kinter CS, Humphries KM, Mather T, Szweda LI, Kinter M. Lysine Acetylation Activates Mitochondrial Aconitase in the Heart. Biochemistry 2015; 54:4008-18. [PMID: 26061789 DOI: 10.1021/acs.biochem.5b00375] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
High-throughput proteomics studies have identified several thousand acetylation sites on more than 1000 proteins. Mitochondrial aconitase, the Krebs cycle enzyme that converts citrate to isocitrate, has been identified in many of these reports. Acetylated mitochondrial aconitase has also been identified as a target for sirtuin 3 (SIRT3)-catalyzed deacetylation. However, the functional significance of mitochondrial aconitase acetylation has not been determined. Using in vitro strategies, mass spectrometric analyses, and an in vivo mouse model of obesity, we found a significant acetylation-dependent activation of aconitase. Isolated heart mitochondria subjected to in vitro chemical acetylation with either acetic anhydride or acetyl-coenzyme A resulted in increased aconitase activity that was reversed with SIRT3 treatment. Quantitative mass spectrometry was used to measure acetylation at 21 lysine residues and revealed significant increases with both in vitro treatments. A high-fat diet (60% of kilocalories from fat) was used as an in vivo model and also showed significantly increased mitochondrial aconitase activity without changes in protein level. The high-fat diet also produced an increased level of aconitase acetylation at multiple sites as measured by the quantitative mass spectrometry assays. Treatment of isolated mitochondria from these mice with SIRT3 abolished the high-fat diet-induced activation of aconitase and reduced acetylation. Finally, kinetic analyses found that the increase in activity was a result of increased maximal velocity, and molecular modeling suggests the potential for acetylation at K144 to perturb the tertiary structure of the enzyme. The results of this study reveal a novel activation of mitochondrial aconitase by acetylation.
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Affiliation(s)
- Jolyn Fernandes
- †Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104, United States.,‡Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, United States
| | - Alexis Weddle
- †Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104, United States
| | - Caroline S Kinter
- †Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104, United States
| | - Kenneth M Humphries
- †Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104, United States.,‡Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, United States.,∥Reynolds Oklahoma Center on Aging, Donald W. Reynolds Department of Geriatric Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, United States
| | - Timothy Mather
- ‡Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, United States.,§Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104, United States
| | - Luke I Szweda
- †Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104, United States.,‡Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, United States.,∥Reynolds Oklahoma Center on Aging, Donald W. Reynolds Department of Geriatric Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, United States
| | - Michael Kinter
- †Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104, United States.,∥Reynolds Oklahoma Center on Aging, Donald W. Reynolds Department of Geriatric Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, United States
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26
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Yao L, Heuser-Baker J, Herlea-Pana O, Zhang N, Szweda LI, Griffin TM, Barlic-Dicen J. Deficiency in adipocyte chemokine receptor CXCR4 exacerbates obesity and compromises thermoregulatory responses of brown adipose tissue in a mouse model of diet-induced obesity. FASEB J 2014; 28:4534-50. [PMID: 25016030 DOI: 10.1096/fj.14-249797] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [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: 11/11/2022]
Abstract
The chemokine receptor CXCR4 is expressed on adipocytes and macrophages in adipose tissue, but its role in this tissue remains unknown. We evaluated whether deficiency in either adipocyte or myeloid leukocyte CXCR4 affects body weight (BW) and adiposity in a mouse model of high-fat-diet (HFD)-induced obesity. We found that ablation of adipocyte, but not myeloid leukocyte, CXCR4 exacerbated obesity. The HFD-fed adipocyte-specific CXCR4-knockout (AdCXCR4ko) mice, compared to wild-type C57BL/6 control mice, had increased BW (average: 52.0 g vs. 35.5 g), adiposity (average: 49.3 vs. 21.0% of total BW), and inflammatory leukocyte content in white adipose tissue (WAT), despite comparable food intake. As previously reported, HFD feeding increased uncoupling protein 1 (UCP1) expression (fold increase: 3.5) in brown adipose tissue (BAT) of the C57BL/6 control mice. However, no HFD-induced increase in UCP1 expression was observed in the AdCXCR4ko mice, which were cold sensitive. Thus, our study suggests that adipocyte CXCR4 limits development of obesity by preventing excessive inflammatory cell recruitment into WAT and by supporting thermogenic activity of BAT. Since CXCR4 is conserved between mouse and human, the newfound role of CXCR4 in mouse adipose tissue may parallel the role of this chemokine receptor in human adipose tissue.
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Affiliation(s)
| | | | | | | | - Luke I Szweda
- Free Radical Biology and Aging Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - Timothy M Griffin
- Free Radical Biology and Aging Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
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27
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Puente BN, Kimura W, Muralidhar SA, Moon J, Amatruda JF, Phelps KL, Grinsfelder D, Rothermel BA, Chen R, Garcia JA, Santos CX, Thet S, Mori E, Kinter MT, Rindler PM, Zacchigna S, Mukherjee S, Chen DJ, Mahmoud AI, Giacca M, Rabinovitch PS, Aroumougame A, Shah AM, Szweda LI, Sadek HA. The oxygen-rich postnatal environment induces cardiomyocyte cell-cycle arrest through DNA damage response. Cell 2014; 157:565-79. [PMID: 24766806 DOI: 10.1016/j.cell.2014.03.032] [Citation(s) in RCA: 587] [Impact Index Per Article: 58.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Revised: 02/17/2014] [Accepted: 03/21/2014] [Indexed: 12/15/2022]
Abstract
The mammalian heart has a remarkable regenerative capacity for a short period of time after birth, after which the majority of cardiomyocytes permanently exit cell cycle. We sought to determine the primary postnatal event that results in cardiomyocyte cell-cycle arrest. We hypothesized that transition to the oxygen-rich postnatal environment is the upstream signal that results in cell-cycle arrest of cardiomyocytes. Here, we show that reactive oxygen species (ROS), oxidative DNA damage, and DNA damage response (DDR) markers significantly increase in the heart during the first postnatal week. Intriguingly, postnatal hypoxemia, ROS scavenging, or inhibition of DDR all prolong the postnatal proliferative window of cardiomyocytes, whereas hyperoxemia and ROS generators shorten it. These findings uncover a protective mechanism that mediates cardiomyocyte cell-cycle arrest in exchange for utilization of oxygen-dependent aerobic metabolism. Reduction of mitochondrial-dependent oxidative stress should be an important component of cardiomyocyte proliferation-based therapeutic approaches.
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Affiliation(s)
- Bao N Puente
- Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Pediatrics, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Wataru Kimura
- Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Shalini A Muralidhar
- Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Jesung Moon
- Department of Pediatrics, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - James F Amatruda
- Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Molecular Biology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Pediatrics, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Kate L Phelps
- Department of Cell Biology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - David Grinsfelder
- Department of Clinical Science, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Beverly A Rothermel
- Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Molecular Biology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Rui Chen
- Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Joseph A Garcia
- Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Celio X Santos
- Cardiovascular Division, King's College London BHF Centre of Research Excellence, School of Medicine, James Black Centre, London SE5 9NU, UK
| | - SuWannee Thet
- Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Eiichiro Mori
- Department of Radiation Oncology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Michael T Kinter
- Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - Paul M Rindler
- Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - Serena Zacchigna
- Molecular Medicine Laboratory, International Centre for Genetic Engineering and Biotechnology, 34149 Trieste, Italy
| | - Shibani Mukherjee
- Department of Radiation Oncology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - David J Chen
- Department of Radiation Oncology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Ahmed I Mahmoud
- Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Cambridge, MA 02115, USA
| | - Mauro Giacca
- Molecular Medicine Laboratory, International Centre for Genetic Engineering and Biotechnology, 34149 Trieste, Italy
| | | | - Asaithamby Aroumougame
- Department of Radiation Oncology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Ajay M Shah
- Department of Clinical Science, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Luke I Szweda
- Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - Hesham A Sadek
- Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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28
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Crewe C, Kinter M, Szweda LI. Rapid inhibition of pyruvate dehydrogenase: an initiating event in high dietary fat-induced loss of metabolic flexibility in the heart. PLoS One 2013; 8:e77280. [PMID: 24116221 PMCID: PMC3792029 DOI: 10.1371/journal.pone.0077280] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [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] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Accepted: 08/31/2013] [Indexed: 11/24/2022] Open
Abstract
Cardiac function depends on the ability to switch between fatty acid and glucose oxidation for energy production in response to changes in substrate availability and energetic stress. In obese and diabetic individuals, increased reliance on fatty acids and reduced metabolic flexibility are thought to contribute to the development of cardiovascular disease. Mechanisms by which cardiac mitochondria contribute to diet-induced metabolic inflexibility were investigated. Mice were fed a high fat or low fat diet for 1 d, 1 wk, and 20 wk. Cardiac mitochondria isolated from mice fed a high fat diet displayed a diminished ability to utilize the glycolytically derived substrate pyruvate. This response was rapid, occurring within the first day on the diet, and persisted for up to 20 wk. A selective increase in the expression of pyruvate dehydrogenase kinase 4 and inhibition of pyruvate dehydrogenase are responsible for the rapid suppression of pyruvate utilization. An important consequence is that pyruvate dehydrogenase is sensitized to inhibition when mitochondria respire in the presence of fatty acids. Additionally, increased expression of pyruvate dehydrogenase kinase 4 preceded any observed diet-induced reductions in the levels of glucose transporter type 4 and glycolytic enzymes and, as judged by Akt phosphorylation, insulin signaling. Importantly, diminished insulin signaling evident at 1 wk on the high fat diet did not occur in pyruvate dehydrogenase kinase 4 knockout mice. Dietary intervention leads to a rapid decline in pyruvate dehydrogenase kinase 4 levels and recovery of pyruvate dehydrogenase activity indicating an additional form of regulation. Finally, an overnight fast elicits a metabolic response similar to that induced by high dietary fat obscuring diet-induced metabolic changes. Thus, our data indicate that diet-induced inhibition of pyruvate dehydrogenase may be an initiating event in decreased oxidation of glucose and increased reliance of the heart on fatty acids for energy production.
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Affiliation(s)
- Clair Crewe
- Free Radical Biology and Aging Research Program Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States of America
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Science Center, Oklahoma City, Oklahoma, United States of America
| | - Michael Kinter
- Free Radical Biology and Aging Research Program Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States of America
- Department of Geriatric Medicine, Reynolds Center on Aging, University of Oklahoma Health Science Center, Oklahoma City, Oklahoma, United States of America
| | - Luke I. Szweda
- Free Radical Biology and Aging Research Program Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States of America
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Science Center, Oklahoma City, Oklahoma, United States of America
- Department of Geriatric Medicine, Reynolds Center on Aging, University of Oklahoma Health Science Center, Oklahoma City, Oklahoma, United States of America
- * E-mail:
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29
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Rindler PM, Crewe CL, Fernandes J, Kinter M, Szweda LI. Redox regulation of insulin sensitivity due to enhanced fatty acid utilization in the mitochondria. Am J Physiol Heart Circ Physiol 2013; 305:H634-43. [DOI: 10.1152/ajpheart.00799.2012] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Obesity enhances the risk for the development of type 2 diabetes and cardiovascular disease. Loss in insulin sensitivity and diminished ability of muscle to take up and use glucose are characteristics of type 2 diabetes. Paradoxically, regulatory mechanisms that promote utilization of fatty acids appear to initiate diet-induced insulin insensitivity. In this review, we discuss recent findings implicating increased mitochondrial production of the prooxidant H2O2 due to enhanced utilization of fatty acids, as a signal to diminish reliance on glucose and its metabolites for energy. In the short term, the ability to preferentially use fatty acids may be beneficial, promoting a metabolic shift that ensures use of available fat by skeletal muscle and heart while preventing intracellular glucose accumulation and toxicity. However, with prolonged consumption of high dietary fat and ensuing obesity, the near exclusive dependence on fatty acid oxidation for production of energy by the mitochondria drives insulin resistance, diabetes, and cardiovascular disease.
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Affiliation(s)
- Paul M. Rindler
- Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
| | - Clair L. Crewe
- Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Science Center, Oklahoma City, Oklahoma; and
| | - Jolyn Fernandes
- Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Science Center, Oklahoma City, Oklahoma; and
| | - Michael Kinter
- Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
- Department of Geriatric Medicine, Reynolds Center on Aging, University of Oklahoma Health Science Center, Oklahoma City, Oklahoma
| | - Luke I. Szweda
- Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Science Center, Oklahoma City, Oklahoma; and
- Department of Geriatric Medicine, Reynolds Center on Aging, University of Oklahoma Health Science Center, Oklahoma City, Oklahoma
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30
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McLain AL, Cormier PJ, Kinter M, Szweda LI. Glutathionylation of α-ketoglutarate dehydrogenase: the chemical nature and relative susceptibility of the cofactor lipoic acid to modification. Free Radic Biol Med 2013; 61:161-9. [PMID: 23567190 PMCID: PMC3883985 DOI: 10.1016/j.freeradbiomed.2013.03.020] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [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: 10/19/2012] [Revised: 03/09/2013] [Accepted: 03/25/2013] [Indexed: 01/13/2023]
Abstract
α-Ketoglutarate dehydrogenase (KGDH) is reversibly inhibited when rat heart mitochondria are exposed to hydrogen peroxide (H2O2). H2O2-induced inhibition occurs through the formation of a mixed disulfide between a protein sulfhydryl and glutathione. Upon consumption of H2O2, glutaredoxin can rapidly remove glutathione, resulting in regeneration of enzyme activity. KGDH is a key regulatory site within the Krebs cycle. Glutathionylation of the enzyme may therefore represent an important means to control mitochondrial function in response to oxidative stress. We have previously provided indirect evidence that glutathionylation occurs on lipoic acid, a cofactor covalently bound to the E2 subunit of KGDH. However, lipoic acid contains two vicinal sulfhydryls and rapid disulfide exchange might be predicted to preclude stable glutathionylation. The current study sought conclusive identification of the site and chemistry of KGDH glutathionylation and factors that control the degree and rate of enzyme inhibition. We present evidence that, upon reaction of free lipoic acid with oxidized glutathione in solution, disulfide exchange occurs rapidly, producing oxidized lipoic acid and reduced glutathione. This prevents the stable formation of a glutathione-lipoic acid adduct. Nevertheless, 1:1 lipoic acid-glutathione adducts are formed on KGDH because the second sulfhydryl on lipoic acid is unable to participate in disulfide exchange in the enzyme's native conformation. The maximum degree of KGDH inhibition that can be achieved by treatment of mitochondria with H2O2 is 50%. Results indicate that this is not due to glutathionylation of a subpopulation of the enzyme but, rather, the unique susceptibility of lipoic acid on a subset of E2 subunits within each enzyme complex. Calcium enhances the rate of glutathionylation by increasing the half-life of reduced lipoic acid during enzyme catalysis. This does not, however, alter the maximal level of inhibition, providing further evidence that specific lipoic acid residues within the E2 complex are susceptible to glutathionylation. These findings offer chemical information necessary for the identification of mechanisms and physiological implications of KGDH glutathionylation.
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Affiliation(s)
- Aaron L McLain
- Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA; Department of Biochemistry and Molecular Biology, University of Oklahoma Health Science Center, Oklahoma City, OK 73104, USA
| | - Peter J Cormier
- Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - Michael Kinter
- Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA; Department of Geriatric Medicine, Reynolds Center on Aging, University of Oklahoma Health Science Center, Oklahoma City, OK 73104, USA
| | - Luke I Szweda
- Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA; Department of Biochemistry and Molecular Biology, University of Oklahoma Health Science Center, Oklahoma City, OK 73104, USA; Department of Geriatric Medicine, Reynolds Center on Aging, University of Oklahoma Health Science Center, Oklahoma City, OK 73104, USA.
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Allen BG, Bhatia SK, Buatti JM, Brandt KE, Lindholm KE, Button AM, Szweda LI, Smith BJ, Spitz DR, Fath MA. Ketogenic diets enhance oxidative stress and radio-chemo-therapy responses in lung cancer xenografts. Clin Cancer Res 2013; 19:3905-13. [PMID: 23743570 DOI: 10.1158/1078-0432.ccr-12-0287] [Citation(s) in RCA: 148] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE Ketogenic diets are high in fat and low in carbohydrates as well as protein which forces cells to rely on lipid oxidation and mitochondrial respiration rather than glycolysis for energy metabolism. Cancer cells (relative to normal cells) are believed to exist in a state of chronic oxidative stress mediated by mitochondrial metabolism. The current study tests the hypothesis that ketogenic diets enhance radio-chemo-therapy responses in lung cancer xenografts by enhancing oxidative stress. EXPERIMENTAL DESIGN Mice bearing NCI-H292 and A549 lung cancer xenografts were fed a ketogenic diet (KetoCal 4:1 fats: proteins+carbohydrates) and treated with either conventionally fractionated (1.8-2 Gy) or hypofractionated (6 Gy) radiation as well as conventionally fractionated radiation combined with carboplatin. Mice weights and tumor size were monitored. Tumors were assessed for immunoreactive 4-hydroxy-2-nonenal-(4HNE)-modified proteins as a marker of oxidative stress as well as proliferating cell nuclear antigen (PCNA) and γH2AX as indices of proliferation and DNA damage, respectively. RESULTS The ketogenic diets combined with radiation resulted in slower tumor growth in both NCI-H292 and A549 xenografts (P < 0.05), relative to radiation alone. The ketogenic diet also slowed tumor growth when combined with carboplatin and radiation, relative to control. Tumors from animals fed a ketogenic diet in combination with radiation showed increases in oxidative damage mediated by lipid peroxidation as determined by 4HNE-modified proteins as well as decreased proliferation as assessed by decreased immunoreactive PCNA. CONCLUSIONS These results show that a ketogenic diet enhances radio-chemo-therapy responses in lung cancer xenografts by a mechanism that may involve increased oxidative stress.
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Affiliation(s)
- Bryan G Allen
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, Iowa 52242, USA
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Perry EA, Castellani RJ, Moreira PI, Nunomura A, Lui Q, Harris PLR, Sayre LM, Szweda PA, Szweda LI, Zhu X, Smith MA, Perry G. Neurofilaments are the major neuronal target of hydroxynonenal-mediated protein cross-links. Free Radic Res 2013; 47:507-10. [PMID: 23566300 DOI: 10.3109/10715762.2013.794265] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Lipid peroxidation generates reactive aldehydes, most notably hydroxynonenal (HNE), which covalently binds amino acid residue side chains leading to protein inactivation and insolubility. Specific adducts of lipid peroxidation have been demonstrated to be intimately associated with pathological lesions of Alzheimer's disease (AD), suggesting that oxidative stress is a major component in the disease. Here, we examined the HNE-cross-linking modifications by using an antibody specific for a lysine-lysine cross-link. Since in a prior study we noted no immunolabeling of neuritic plaques or neurofibrillary tangles but instead found strong labeling of axons, we focused this study on axons. Axonal labeling was examined in mouse sciatic nerve, and immunoblotting showed the cross-link was restricted to neurofilament heavy and medium subunits, which while altering migration, did not indicate larger NF aggregates, indicative of intermolecular cross-links. Examination of mice at various ages showed the extent of modification remaining relatively constant through the life span. These findings demonstrate lipid-cross-linking peroxidation primarily involves lysine-rich neurofilaments and is restricted to intramolecular cross-links.
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Affiliation(s)
- E A Perry
- Department of Biology, The University of Texas at San Antonio, San Antonio, TX, USA
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33
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MacDonald MJ, Langberg EC, Tibell A, Sabat G, Kendrick MA, Szweda LI, Ostenson CG. Identification of ATP synthase as a lipid peroxide protein adduct in pancreatic islets from humans with and without type 2 diabetes mellitus. J Clin Endocrinol Metab 2013; 98:E727-31. [PMID: 23463654 PMCID: PMC3615212 DOI: 10.1210/jc.2012-4203] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Most current knowledge of pancreatic islet pathophysiology in diabetes mellitus has come from animal models. Even though islets from humans are readily available, only a few come from diabetic donors. We had the uncommon opportunity to acquire islets from humans with type 2 diabetes and used it to perform a study not previously done with human or animal islets. OBJECTIVES Oxidative stress has been proposed as a mechanism for impaired β-cell function in type 2 diabetes. Lipid peroxides caused by reactive oxygen species are damaging to body tissues. The objective was to determine whether lipid peroxide-protein adducts occur in pancreatic islets of humans with type 2 diabetes. DESIGN Immunoblots with two antibodies to hydroxynonenal and 2 other antibodies we generated against reactive small aliphatic compounds were used to detect lipid peroxide-protein adducts in islets of patients with type 2 diabetes and controls. RESULTS The antibodies reacted strongly to ≥5 islet proteins. The major hydroxynonenal adduct in the islets of type 2 diabetes patients was a 52-kDa protein seen with all 4 antibodies that was also seen in islets of nondiabetic humans, rat islets, and insulinoma cells and in mitochondria of various rat tissues. Nano-LC-MS/MS (liquid chromatography-tandem mass spectrometry) and MALDI-TOF (matrix-assisted laser desorption/ionization-time of flight) analysis identified the protein as the β-chain of the mitochondrial F-ATP synthase, an enzyme responsible for 95% of ATP formed in tissues. CONCLUSIONS Lipid peroxide-protein adducts occur in β-cells in the nondiabetic state and in diabetes. Lipid peroxidation is thought to be damaging to tissues. Analogous to various other unhealthy characteristics, the presence in nondiabetic individuals of lipid peroxide-protein adducts does not necessarily indicate they are not detrimental.
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Affiliation(s)
- M J MacDonald
- Childrens Diabetes Center, University of Wisconsin School of Medicine and Public Health, Madison, WI 53706, USA.
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34
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Hardas SS, Sultana R, Clark AM, Beckett TL, Szweda LI, Murphy MP, Butterfield DA. Oxidative modification of lipoic acid by HNE in Alzheimer disease brain. Redox Biol 2013; 1:80-5. [PMID: 24024140 PMCID: PMC3757677 DOI: 10.1016/j.redox.2013.01.002] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [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: 12/03/2012] [Revised: 12/27/2012] [Accepted: 01/02/2013] [Indexed: 12/19/2022] Open
Abstract
Alzheimer disease (AD) is an age-related neurodegenerative disease characterized by the presence of three pathological hallmarks: synapse loss, extracellular senile plaques (SP) and intracellular neurofibrillary tangles (NFTs). The major component of SP is amyloid β-peptide (Aβ), which has been shown to induce oxidative stress. The AD brain shows increased levels of lipid peroxidation products, including 4-hydroxy-2-nonenal (HNE). HNE can react covalently with Cys, His, or Lys residues on proteins, altering structure and function of the latter. In the present study we measured the levels of the HNE-modified lipoic acid in brain of subjects with AD and age-matched controls. Lipoic acid is a key co-factor for a number of proteins including pyruvate dehydrogenase and α-ketoglutarate dehydrogenase, key complexes for cellular energetics. We observed a significant decrease in the levels of HNE-lipoic acid in the AD brain compared to that of age-matched controls. To investigate this phenomenon further, the levels and activity of lipoamide dehydrogenase (LADH) were measured in AD and control brains. Additionally, LADH activities were measured after in-vitro HNE-treatment to mice brains. Both LADH levels and activities were found to be significantly reduced in AD brain compared to age-matched control. HNE-treatment also reduced the LADH activity in mice brain. These data are consistent with a two-hit hypothesis of AD: oxidative stress leads to lipid peroxidation that, in turn, causes oxidative dysfunction of key energy-related complexes in mitochondria, triggering neurodegeneration. This study is consonant with the notion that lipoic acid supplementation could be a potential treatment for the observed loss of cellular energetics in AD and potentiate the antioxidant defense system to prevent or delay the oxidative stress in and progression of this devastating dementing disorder.
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Affiliation(s)
- Sarita S Hardas
- Department of Chemistry, University of Kentucky, Lexington, KY 40506-0055, USA ; Center for Membrane Sciences, University of Kentucky, Lexington, KY 40506-0055, USA ; Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY 40506-0055, USA
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Abstract
Obesity is a predictor of diabetes and cardiovascular disease. One consequence of obesity is dyslipidemia characterized by high blood triglycerides. It has been proposed that oxidative stress, driven by utilization of lipids for energy, contributes to these diseases. The effects of oxidative stress are mitigated by an endogenous antioxidant enzyme network, but little is known about its response to high fat utilization. Our experiments used a multiplexed quantitative proteomics method to measure antioxidant enzyme expression in heart tissue in a mouse model of diet-induced obesity. This experiment showed a rapid and specific up-regulation of catalase protein, with subsequent assays showing increases in activity and mRNA. Catalase, traditionally considered a peroxisomal protein, was found to be present in cardiac mitochondria and significantly increased in content and activity during high fat feeding. These data, coupled with the fact that fatty acid oxidation enhances mitochondrial H(2)O(2) production, suggest that a localized catalase increase is needed to consume excessive mitochondrial H(2)O(2) produced by increased fat metabolism. To determine whether the catalase-specific response is a common feature of physiological conditions that increase blood triglycerides and fatty acid oxidation, we measured changes in antioxidant expression in fasted versus fed mice. Indeed, a similar specific catalase increase was observed in mice fasted for 24 h. Our findings suggest a fundamental metabolic process in which catalase expression is regulated to prevent damage while preserving an H(2)O(2)-mediated sensing of diet composition that appropriately adjusts insulin sensitivity in the short term as needed to prioritize lipid metabolism for complete utilization.
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Affiliation(s)
- Paul M Rindler
- Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
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36
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Fernandes J, Szweda LI, Kinter M. Enhanced cardiac fatty acid utilization induced by high dietary fat: a potential regulatory role for mitochondrial aconitase. BMC Proc 2012. [PMCID: PMC3374215 DOI: 10.1186/1753-6561-6-s3-p15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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37
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Zhu X, Castellani RJ, Moreira PI, Aliev G, Shenk JC, Siedlak SL, Harris PLR, Fujioka H, Sayre LM, Szweda PA, Szweda LI, Smith MA, Perry G. Hydroxynonenal-generated crosslinking fluorophore accumulation in Alzheimer disease reveals a dichotomy of protein turnover. Free Radic Biol Med 2012; 52:699-704. [PMID: 22137893 PMCID: PMC3268699 DOI: 10.1016/j.freeradbiomed.2011.11.004] [Citation(s) in RCA: 33] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Revised: 10/28/2011] [Accepted: 11/03/2011] [Indexed: 11/22/2022]
Abstract
Lipid peroxidation generates reactive aldehydes, most notably hydroxynonenal (HNE), which covalently bind amino acid residue side chains leading to protein inactivation and insolubility. Specific adducts of lipid peroxidation have been demonstrated in intimate association with the pathological lesions of Alzheimer disease (AD), suggesting that oxidative stress is a major component of AD pathogenesis. Some HNE-protein products result in protein crosslinking through a fluorescent compound similar to lipofuscin, linking lipid peroxidation and the lipofuscin accumulation that commonly occurs in post-mitotic cells such as neurons. In this study, brain tissue from AD and control patients was examined by immunocytochemistry and immunoelectron microscopy for evidence of HNE-crosslinking modifications of the type that should accumulate in the lipofuscin pathway. Strong labeling of granulovacuolar degeneration (GVD) and Hirano bodies was noted but lipofuscin did not contain this specific HNE-fluorophore. These findings directly implicate lipid crosslinking peroxidation products as accumulating not in the lesions or the lipofuscin pathways, but instead in a distinct pathway, GVD, that accumulates cytosolic proteins.
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Affiliation(s)
- Xiongwei Zhu
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio, USA.
| | - Rudy J Castellani
- Department of Pathology, University of Maryland, Baltimore, Maryland, USA
| | - Paula I Moreira
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Gjumrakch Aliev
- Institute for Neuroscience, University of Texas at San Antonio, San Antonio, Texas, USA
| | - Justin C Shenk
- Institute for Neuroscience, University of Texas at San Antonio, San Antonio, Texas, USA
| | - Sandra L Siedlak
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio, USA
| | - Peggy L R Harris
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio, USA
| | - Hisashi Fujioka
- Department of Pharmacology, Case Western Reserve University, Cleveland, Ohio, USA
| | - Lawrence M Sayre
- Department of Chemistry, Case Western Reserve University, Cleveland, Ohio, USA
| | - Pamela A Szweda
- Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Luke I Szweda
- Free Radical Biology and Aging Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - Mark A Smith
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio, USA
| | - George Perry
- Institute for Neuroscience, University of Texas at San Antonio, San Antonio, Texas, USA.
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Abstract
Clinical and experimental evidence supports that chronic oxidative stress is a primary contributing factor to numerous retinal degenerative diseases, such as age-related macular degeneration (AMD). Eyes obtained postmortem from AMD patients have extensive free radical damage to the proteins, lipids, DNA, and mitochondria of their retinal pigment epithelial (RPE) cells. In addition, several mouse models of chronic oxidative stress develop many of the pathological hallmarks of AMD. However, the extent to which oxidative stress is an etiologic component versus its involvement in disease progression remains a major unanswered question. Further, whether the primary target of oxidative stress and damage is photoreceptors or RPE cells, or both, is still unclear. In this review, we discuss the major functions of RPE cells with an emphasis on the oxidative challenges these cells encounter and the endogenous antioxidant mechanisms employed to neutralize the deleterious effects that such stresses can elicit if left unchecked.
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Affiliation(s)
- Scott M Plafker
- Free Radical Biology and Aging Program, Oklahoma Medical Research Foundation, Oklahoma City, USA
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39
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Dasuri K, Zhang L, Ebenezer P, Fernandez-Kim SO, Bruce-Keller AJ, Szweda LI, Keller JN. Proteasome alterations during adipose differentiation and aging: links to impaired adipocyte differentiation and development of oxidative stress. Free Radic Biol Med 2011; 51:1727-35. [PMID: 21871954 PMCID: PMC3378646 DOI: 10.1016/j.freeradbiomed.2011.08.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [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: 06/22/2011] [Revised: 07/29/2011] [Accepted: 08/02/2011] [Indexed: 02/07/2023]
Abstract
Intracellular proteins are degraded by a number of proteases, including the ubiquitin-proteasome pathway (UPP). Impairments in the UPP occur during the aging of a variety of tissues, although little is known in regards to age-related alterations to the UPP during the aging of adipose tissue. The UPP is known to be involved in regulating the differentiation of a variety of cell types, although the potential changes in the UPP during adipose differentiation have not been fully elucidated. How the UPP is altered in aging adipose tissue and adipocyte differentiation and the effects of proteasome inhibition on adipocyte homeostasis and differentiation are critical issues to elucidate experimentally. Adipogenesis continues throughout the life of adipose tissue, with continual differentiation of preadipocytes essential to maintaining tissue function during aging, and UPP alterations in mature adipocytes are likely to directly modulate adipose function during aging. In this study we demonstrate that aging induces alterations in the activity and expression of principal components of the UPP. Additionally, we show that multiple changes in the UPP occur during the differentiation of 3T3-L1 cells into adipocytes. In vitro data link observed UPP alterations to increased levels of oxidative stress and altered adipose biology relevant to both aging and differentiation. Taken together, these data demonstrate that changes in the UPP occur in response to adipose aging and adipogenesis and strongly suggest that proteasome inhibition is sufficient to decrease adipose differentiation, as well as increasing oxidative stress in mature adipocytes, both of which probably promote deleterious effects on adipose aging.
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Affiliation(s)
- Kalavathi Dasuri
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge Louisiana 70808
| | - Le Zhang
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge Louisiana 70808
| | - Philip Ebenezer
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge Louisiana 70808
| | - Sun Ok Fernandez-Kim
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge Louisiana 70808
| | - Annadora J. Bruce-Keller
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge Louisiana 70808
| | - Luke I. Szweda
- Free Radical Biology and Aging Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - Jeffrey N. Keller
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge Louisiana 70808
- Address correspondence to: Dr Jeffrey N Keller, Pennington Biomedical Research Center, 6400 Perkins Road, Baton Rouge Louisiana 70808, (P) 225-763-3190 (E)
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40
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Abstract
α-Ketoglutarate dehydrogenase (KGDH), a key regulatory enzyme within the Krebs cycle, is sensitive to mitochondrial redox status. Treatment of mitochondria with H₂O₂ results in reversible inhibition of KGDH due to glutathionylation of the cofactor, lipoic acid. Upon consumption of H₂O₂, glutathione is removed by glutaredoxin restoring KGDH activity. Glutathionylation appears to be enzymatically catalysed or require a unique microenvironment. This may represent an antioxidant response, diminishing the flow of electrons to the respiratory chain and protecting sulphydryl residues from oxidative damage. KGDH is, however, also susceptible to oxidative damage. 4-Hydroxy-2-nonenal (HNE), a lipid peroxidation product, reacts with lipoic acid resulting in enzyme inactivation. Evidence indicates that HNE modified lipoic acid is cleaved from KGDH, potentially the first step of a repair process. KGDH is therefore a likely redox sensor, reversibly altering metabolism to reduce oxidative damage and, under severe oxidative stress, acting as a sentinel of mitochondrial viability.
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Affiliation(s)
- Aaron L McLain
- Free Radical Biology and Aging Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104, USA
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41
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Shenk JC, Smith MA, Castellani RJ, Moreira P, Aliev G, Siedlak SL, Harris PL, Sayre L, Szweda PA, Szweda LI, Perry G. P1‐196: Lipid peroxidation markers are associated with granulovacuolar degeneration but not lipofuscin formation. Alzheimers Dement 2010. [DOI: 10.1016/j.jalz.2010.05.746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
| | | | | | | | | | | | | | | | - Pamela A. Szweda
- University of Oklahoma Health Sciences CenterOklahoma City OK USA
| | - Luke I. Szweda
- University of Oklahoma Health Sciences CenterOklahoma City OK USA
| | - George Perry
- University of Texas at San AntonioSan Antonio TX USA
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Cussiol JRR, Alegria TGP, Szweda LI, Netto LES. Ohr (organic hydroperoxide resistance protein) possesses a previously undescribed activity, lipoyl-dependent peroxidase. J Biol Chem 2010; 285:21943-50. [PMID: 20463026 DOI: 10.1074/jbc.m110.117283] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The Ohr (organic hydroperoxide resistance) family of 15-kDa Cys-based, thiol-dependent peroxidases is central to the bacterial response to stress induced by organic hydroperoxides but not by hydrogen peroxide. Ohr has a unique three-dimensional structure and requires dithiols, but not monothiols, to support its activity. However, the physiological reducing system of Ohr has not yet been identified. Here we show that lipoylated enzymes present in the bacterial extracts of Xylella fastidiosa interacted physically and functionally with this Cys-based peroxidase, whereas thioredoxin and glutathione systems failed to support Ohr peroxidase activity. Furthermore, we could reconstitute in vitro three lipoyl-dependent systems as the Ohr physiological reducing systems. We also showed that OsmC from Escherichia coli, an orthologue of Ohr from Xylella fastidiosa, is specifically reduced by lipoyl-dependent systems. These results represent the first description of a Cys-based peroxidase that is directly reduced by lipoylated enzymes.
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Affiliation(s)
- José R R Cussiol
- Departamento de Genética e Biologia Evolutiva, Instituto de Biociencias, Universidade de Sao Paulo, Rua do Matão 277, São Paulo 05508-900, Brazil
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43
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Churchill EN, Ferreira JC, Brum PC, Szweda LI, Mochly-Rosen D. Ischaemic preconditioning improves proteasomal activity and increases the degradation of deltaPKC during reperfusion. Cardiovasc Res 2009; 85:385-94. [PMID: 19820255 PMCID: PMC2797452 DOI: 10.1093/cvr/cvp334] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Aims The response of the myocardium to an ischaemic insult is regulated by two highly homologous protein kinase C (PKC) isozymes, δ and εPKC. Here, we determined the spatial and temporal relationships between these two isozymes in the context of ischaemia/reperfusion (I/R) and ischaemic preconditioning (IPC) to better understand their roles in cardioprotection. Methods and results Using an ex vivo rat model of myocardial infarction, we found that short bouts of ischaemia and reperfusion prior to the prolonged ischaemic event (IPC) diminished δPKC translocation by 3.8-fold and increased εPKC accumulation at mitochondria by 16-fold during reperfusion. In addition, total cellular levels of δPKC decreased by 60 ± 2.7% in response to IPC, whereas the levels of εPKC did not significantly change. Prolonged ischaemia induced a 48 ± 11% decline in the ATP-dependent proteasomal activity and increased the accumulation of misfolded proteins during reperfusion by 192 ± 32%; both of these events were completely prevented by IPC. Pharmacological inhibition of the proteasome or selective inhibition of εPKC during IPC restored δPKC levels at the mitochondria while decreasing εPKC levels, resulting in a loss of IPC-induced protection from I/R. Importantly, increased myocardial injury was the result, in part, of restoring a δPKC-mediated I/R pro-apoptotic phenotype by decreasing pro-survival signalling and increasing cytochrome c release into the cytosol. Conclusion Taken together, our findings indicate that IPC prevents I/R injury at reperfusion by protecting ATP-dependent 26S proteasomal function. This decreases the accumulation of the pro-apoptotic kinase, δPKC, at cardiac mitochondria, resulting in the accumulation of the pro-survival kinase, εPKC.
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Affiliation(s)
- Eric N Churchill
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305-5174, USA
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44
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Abstract
Proteins, nucleic acids, and lipids can undergo various forms of oxidative modification. In numerous instances, these modifications result in irreversible loss of function. The age-dependent accumulation of oxidatively modified and dysfunctional macromolecules provides the basis for the free radical theory of aging. Pro-oxidants, however, are also capable of catalyzing fully reversible modifications to protein. It is increasingly apparent that these reactions participate in redox-dependent regulation of cell metabolism and response to stress. The adventitious use of free radical species adds complexity to the experimental and theoretical manner in which the free radical theory is to be tested and considered. Elucidation of mechanisms by which reversible oxidative processes are controlled, the components involved, and the metabolic consequences and how they are altered with age will provide new insight on the aging process and attempts to delay the inevitable.
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45
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Matsuzaki S, Szweda LI, Humphries KM. Mitochondrial superoxide production and respiratory activity: biphasic response to ischemic duration. Arch Biochem Biophys 2009; 484:87-93. [PMID: 19467633 PMCID: PMC2687324 DOI: 10.1016/j.abb.2009.01.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [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: 11/03/2008] [Revised: 12/24/2008] [Accepted: 01/06/2009] [Indexed: 01/25/2023]
Abstract
Long bouts of ischemia are associated with electron transport chain deficits and increases in free radical production. In contrast, little is known regarding the effect of brief ischemia on mitochondrial function and free radical production. This study was undertaken to examine the relationship between the duration of ischemia, effects upon electron transport chain activities, and the mitochondrial production of free radicals. Rat hearts were subjected to increasing ischemic durations, mitochondria were isolated, and superoxide production and electron transport chain activities were measured. Results indicate that even brief ischemic durations induced a significant increase in superoxide production. This rate was maintained with ischemic durations less than 15 min, and then increased further with longer ischemic times. Mechanistically, brief ischemia was accompanied by an increase in NADH oxidase activity, reflected by a specific increase in complex IV activity. In contrast, longer ischemic durations were accompanied by a decrease in NADH oxidase activity, reflected by deficits in complexes I and IV activities.
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Affiliation(s)
- Satoshi Matsuzaki
- Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
| | - Luke I. Szweda
- Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
| | - Kenneth M. Humphries
- Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
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Wu M, Chen Y, Wilson K, Chirindel A, Ihnat MA, Yu Y, Boulton ME, Szweda LI, Ma JX, Lyons TJ. Intraretinal leakage and oxidation of LDL in diabetic retinopathy. Invest Ophthalmol Vis Sci 2008; 49:2679-85. [PMID: 18362112 DOI: 10.1167/iovs.07-1440] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE The pathogenesis of diabetic retinopathy (DR) is not fully understood. Clinical studies suggest that dyslipidemia is associated with the initiation and progression of DR. However, no direct evidence supports this theory. METHODS Immunostaining of apolipoprotein B100 (ApoB100, a marker of low-density lipoprotein [LDL]), macrophages, and oxidized LDL was performed in retinal sections from four different groups of subjects: nondiabetic, type 2 diabetic without clinical retinopathy, diabetic with moderate nonproliferative diabetic retinopathy (NPDR), and diabetic with proliferative diabetic retinopathy (PDR). Apoptosis was characterized using the TUNEL assay. In addition, in cell culture studies using in vitro-modified LDL, the induction of apoptosis by heavily oxidized-glycated LDL (HOG-LDL) in human retinal capillary pericytes (HRCPs) was assessed. RESULTS Intraretinal immunofluorescence of ApoB100 increased with the severity of DR. Macrophages were prominent only in sections from diabetic patients with PDR. Merged images revealed that ApoB100 partially colocalized with macrophages. Intraretinal oxidized LDL was absent in nondiabetic subjects but present in all three diabetic groups, increasing with the severity of DR. TUNEL-positive cells were present in retinas from diabetic subjects but absent in those from nondiabetic subjects. In cell culture, HOG-LDL induced the activation of caspase, mitochondrial dysfunction, and apoptosis in HRCPs. CONCLUSIONS These findings suggest a potentially important role for extravasated, modified LDL in promoting DR by promoting apoptotic pericyte loss.
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Affiliation(s)
- Mingyuan Wu
- Harold Hamm Oklahoma Diabetes Center and the Section of Endocrinology and Diabetes, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, USA
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47
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Martin CM, Ferdous A, Gallardo T, Humphries C, Sadek H, Caprioli A, Garcia JA, Szweda LI, Garry MG, Garry DJ. Hypoxia-inducible factor-2alpha transactivates Abcg2 and promotes cytoprotection in cardiac side population cells. Circ Res 2008; 102:1075-81. [PMID: 18356544 DOI: 10.1161/circresaha.107.161729] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Stem and progenitor cell populations occupy a specialized niche and are consequently exposed to hypoxic as well as oxidative stresses. We have previously established that the multidrug resistance protein Abcg2 is the molecular determinant of the side population (SP) progenitor cell population. We observed that the cardiac SP cells increase in number more than 3-fold within 3 days of injury. Transcriptome analysis of the SP cells isolated from the injured adult murine heart reveals increased expression of cytoprotective transcripts. Overexpression of Abcg2 results in an increased ability to consume hydrogen peroxide and is associated with increased levels of alpha-glutathione reductase protein expression. Importantly, overexpression of Abcg2 also conferred a cell survival benefit following exposure to hydrogen peroxide. To further examine the molecular regulation of the Abcg2 gene, we demonstrated that hypoxia-inducible factor (HIF)-2alpha binds an evolutionary conserved HIF-2alpha response element in the murine Abcg2 promoter. Transcriptional assays reveal a dose-dependent activation of Abcg2 expression by HIF-2alpha. These results support the hypothesis that Abcg2 is a direct downstream target of HIF-2alpha which functions with other factors to initiate a cytoprotective program for this progenitor SP cell population that resides in the adult heart.
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Affiliation(s)
- Cindy M Martin
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, USA
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48
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Applegate MAB, Humphries KM, Szweda LI. Reversible Inhibition of α-Ketoglutarate Dehydrogenase by Hydrogen Peroxide: Glutathionylation and Protection of Lipoic Acid. Biochemistry 2007; 47:473-8. [DOI: 10.1021/bi7017464] [Citation(s) in RCA: 107] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Milana A. B. Applegate
- Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
| | - Kenneth M. Humphries
- Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
| | - Luke I. Szweda
- Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
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49
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Moreira PI, Siedlak SL, Wang X, Santos MS, Oliveira CR, Tabaton M, Nunomura A, Szweda LI, Aliev G, Smith MA, Zhu X, Perry G. Increased autophagic degradation of mitochondria in Alzheimer disease. Autophagy 2007; 3:614-5. [PMID: 17786024 DOI: 10.4161/auto.4872] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Extensive literature exists supporting a role for mitochondrial dysfunction and oxidative damage in the pathogenesis of Alzheimer disease. Mitochondria are a major source of intracellular reactive oxygen species and are themselves particularly vulnerable to oxidative stress. It has been recently shown that the immunoreactivity of lipoic acid and cytochrome oxidase-1, two mitochondrial markers, is increased in the cytoplasm of pyramidal neurons in Alzheimer disease cases compared with controls. Furthermore, lipoic acid was found to be strongly associated with granular structures and, by ultrastructure analysis, shown to be localized in mitochondria, cytosol and, importantly, in organelles identified as autophagic vacuoles. Lipoic acid was also found associated with the electron dense core of lipofuscin in the brains of Alzheimer disease cases but not in controls, whereas cytochrome oxidase-1 immunoreactivity was limited to mitochondria and cytosol in both Alzheimer and control cases. These data suggest that mitochondria are key targets of increased autophagic degradation in Alzheimer disease. The study of autophagy in Alzheimer disease could clarify the mechanisms underlying this neurodegenerative disorder and, eventually, help in the development of new therapeutic strategies.
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Affiliation(s)
- Paula I Moreira
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio, USA
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50
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Moreira PI, Siedlak SL, Wang X, Santos MS, Oliveira CR, Tabaton M, Nunomura A, Szweda LI, Aliev G, Smith MA, Zhu X, Perry G. Autophagocytosis of Mitochondria Is Prominent in Alzheimer Disease. J Neuropathol Exp Neurol 2007; 66:525-32. [PMID: 17549012 DOI: 10.1097/01.jnen.0000240476.73532.b0] [Citation(s) in RCA: 120] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Mitochondrial abnormalities are prominent in Alzheimer disease. In this study, 2 mitochondrial markers, cytochrome oxidase-1 and lipoic acid, a sulfur-containing cofactor required for the activity of several mitochondrial enzyme complexes, were compared using light and electron microscopic analyses and immunoblot assays. Both lipoic acid and cytochrome oxidase-1 immunoreactivity are increased in the cytoplasm of pyramidal neurons in Alzheimer disease compared with control cases. Of significance, lipoic acid was found to be strongly associated with granular structures, and ultrastructure analysis showed localization to mitochondria, cytosol, and, importantly, in organelles identified as autophagic vacuoles and lipofuscin in Alzheimer disease but not control cases. Cytochrome oxidase-1 immunoreactivity was limited to mitochondria and cytosol in both Alzheimer and control cases. These data suggest that mitochondria are key targets of increased autophagic degradation in Alzheimer disease. Whether increased autophagocytosis is a consequence of an increased turnover of mitochondria or whether the mitochondria in Alzheimer disease are more susceptible to autophagy remains to be resolved.
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Affiliation(s)
- Paula I Moreira
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio, USA
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