1
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Gopal K, Abdualkader AM, Li X, Greenwell AA, Karwi QG, Altamimi TR, Saed C, Uddin GM, Darwesh AM, Jamieson KL, Kim R, Eaton F, Seubert JM, Lopaschuk GD, Ussher JR, Al Batran R. Loss of muscle PDH induces lactic acidosis and adaptive anaplerotic compensation via pyruvate-alanine cycling and glutaminolysis. J Biol Chem 2023; 299:105375. [PMID: 37865313 PMCID: PMC10692893 DOI: 10.1016/j.jbc.2023.105375] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 10/03/2023] [Accepted: 10/11/2023] [Indexed: 10/23/2023] Open
Abstract
Pyruvate dehydrogenase (PDH) is the rate-limiting enzyme for glucose oxidation that links glycolysis-derived pyruvate with the tricarboxylic acid (TCA) cycle. Although skeletal muscle is a significant site for glucose oxidation and is closely linked with metabolic flexibility, the importance of muscle PDH during rest and exercise has yet to be fully elucidated. Here, we demonstrate that mice with muscle-specific deletion of PDH exhibit rapid weight loss and suffer from severe lactic acidosis, ultimately leading to early mortality under low-fat diet provision. Furthermore, loss of muscle PDH induces adaptive anaplerotic compensation by increasing pyruvate-alanine cycling and glutaminolysis. Interestingly, high-fat diet supplementation effectively abolishes early mortality and rescues the overt metabolic phenotype induced by muscle PDH deficiency. Despite increased reliance on fatty acid oxidation during high-fat diet provision, loss of muscle PDH worsens exercise performance and induces lactic acidosis. These observations illustrate the importance of muscle PDH in maintaining metabolic flexibility and preventing the development of metabolic disorders.
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Affiliation(s)
- Keshav Gopal
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada; Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta, Canada; Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada
| | - Abdualrahman Mohammed Abdualkader
- Faculty of Pharmacy, Université de Montréal, Montréal, Quebec, Canada; Montreal Diabetes Research Center, Montréal, Quebec, Canada; Cardiometabolic Health, Diabetes and Obesity Research Network, Montréal, Quebec, Canada
| | - Xiaobei Li
- Faculty of Pharmacy, Université de Montréal, Montréal, Quebec, Canada; Montreal Diabetes Research Center, Montréal, Quebec, Canada; Cardiometabolic Health, Diabetes and Obesity Research Network, Montréal, Quebec, Canada
| | - Amanda A Greenwell
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada; Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta, Canada; Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada
| | - Qutuba G Karwi
- Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta, Canada; Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada; Division of BioMedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, Saint John's, Newfoundland and Labrador, Canada
| | - Tariq R Altamimi
- Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta, Canada; Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada
| | - Christina Saed
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada; Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta, Canada; Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada
| | - Golam M Uddin
- Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta, Canada; Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada
| | - Ahmed M Darwesh
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada; Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada
| | - K Lockhart Jamieson
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada; Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada
| | - Ryekjang Kim
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada; Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta, Canada; Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada
| | - Farah Eaton
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada; Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta, Canada; Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada
| | - John M Seubert
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada; Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada
| | - Gary D Lopaschuk
- Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta, Canada; Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada
| | - John R Ussher
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada; Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta, Canada; Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada
| | - Rami Al Batran
- Faculty of Pharmacy, Université de Montréal, Montréal, Quebec, Canada; Montreal Diabetes Research Center, Montréal, Quebec, Canada; Cardiometabolic Health, Diabetes and Obesity Research Network, Montréal, Quebec, Canada.
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2
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Greenwell AA, Gopal K, Altamimi TR, Saed CT, Wang F, Tabatabaei Dakhili SA, Ho KL, Zhang L, Eaton F, Kruger J, Al Batran R, Lopaschuk GD, Oudit GY, Ussher JR. Barth syndrome-related cardiomyopathy is associated with a reduction in myocardial glucose oxidation. Am J Physiol Heart Circ Physiol 2021; 320:H2255-H2269. [PMID: 33929899 DOI: 10.1152/ajpheart.00873.2020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Heart failure presents as the leading cause of infant mortality in individuals with Barth syndrome (BTHS), a rare genetic disorder due to mutations in the tafazzin (TAZ) gene affecting mitochondrial structure and function. Investigations into the perturbed bioenergetics in the BTHS heart remain limited. Hence, our objective was to identify the potential alterations in myocardial energy metabolism and molecular underpinnings that may contribute to the early cardiomyopathy and heart failure development in BTHS. Cardiac function and myocardial energy metabolism were assessed via ultrasound echocardiography and isolated working heart perfusions, respectively, in a mouse model of BTHS [doxycycline-inducible Taz knockdown (TazKD) mice]. In addition, we also performed mRNA/protein expression profiling for key regulators of energy metabolism in hearts from TazKD mice and their wild-type (WT) littermates. TazKD mice developed hypertrophic cardiomyopathy as evidenced by increased left ventricular anterior and posterior wall thickness, as well as increased cardiac myocyte cross-sectional area, though no functional impairments were observed. Glucose oxidation rates were markedly reduced in isolated working hearts from TazKD mice compared with their WT littermates in the presence of insulin, which was associated with decreased pyruvate dehydrogenase activity. Conversely, myocardial fatty acid oxidation rates were elevated in TazKD mice, whereas no differences in glycolytic flux or ketone body oxidation rates were observed. Our findings demonstrate that myocardial glucose oxidation is impaired before the development of overt cardiac dysfunction in TazKD mice, and may thus represent a pharmacological target for mitigating the development of cardiomyopathy in BTHS.NEW & NOTEWORTHY Barth syndrome (BTHS) is a rare genetic disorder due to mutations in tafazzin that is frequently associated with infantile-onset cardiomyopathy and subsequent heart failure. Although previous studies have provided evidence of perturbed myocardial energy metabolism in BTHS, actual measurements of flux are lacking. We now report a complete energy metabolism profile that quantifies flux in isolated working hearts from a murine model of BTHS, demonstrating that BTHS is associated with a reduction in glucose oxidation.
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Affiliation(s)
- Amanda A Greenwell
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Alberta, Canada.,Cardiovascular Research Centre, University of Alberta, Alberta, Canada.,Women and Children's Health Research Institute, University of Alberta, Alberta, Canada
| | - Keshav Gopal
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Alberta, Canada.,Cardiovascular Research Centre, University of Alberta, Alberta, Canada.,Women and Children's Health Research Institute, University of Alberta, Alberta, Canada
| | - Tariq R Altamimi
- Department of Pediatrics, University of Alberta, Alberta, Canada.,Cardiovascular Research Centre, University of Alberta, Alberta, Canada.,Women and Children's Health Research Institute, University of Alberta, Alberta, Canada
| | - Christina T Saed
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Alberta, Canada.,Cardiovascular Research Centre, University of Alberta, Alberta, Canada.,Women and Children's Health Research Institute, University of Alberta, Alberta, Canada
| | - Faqi Wang
- Cardiovascular Research Centre, University of Alberta, Alberta, Canada.,Divsion of Cardiology, Department of Medicine, University of Alberta, Alberta, Canada.,Mazankowski Alberta Heart Institute, University of Alberta, Alberta, Canada
| | - Seyed Amirhossein Tabatabaei Dakhili
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Alberta, Canada.,Cardiovascular Research Centre, University of Alberta, Alberta, Canada.,Women and Children's Health Research Institute, University of Alberta, Alberta, Canada
| | - Kim L Ho
- Department of Pediatrics, University of Alberta, Alberta, Canada.,Cardiovascular Research Centre, University of Alberta, Alberta, Canada.,Women and Children's Health Research Institute, University of Alberta, Alberta, Canada
| | - Liyan Zhang
- Department of Pediatrics, University of Alberta, Alberta, Canada.,Cardiovascular Research Centre, University of Alberta, Alberta, Canada.,Women and Children's Health Research Institute, University of Alberta, Alberta, Canada
| | - Farah Eaton
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Alberta, Canada.,Cardiovascular Research Centre, University of Alberta, Alberta, Canada.,Women and Children's Health Research Institute, University of Alberta, Alberta, Canada
| | - Jennifer Kruger
- Health Sciences Laboratory Animal Services, University of Alberta, Alberta, Canada
| | - Rami Al Batran
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Alberta, Canada.,Cardiovascular Research Centre, University of Alberta, Alberta, Canada.,Women and Children's Health Research Institute, University of Alberta, Alberta, Canada
| | - Gary D Lopaschuk
- Department of Pediatrics, University of Alberta, Alberta, Canada.,Cardiovascular Research Centre, University of Alberta, Alberta, Canada.,Women and Children's Health Research Institute, University of Alberta, Alberta, Canada.,Mazankowski Alberta Heart Institute, University of Alberta, Alberta, Canada
| | - Gavin Y Oudit
- Cardiovascular Research Centre, University of Alberta, Alberta, Canada.,Divsion of Cardiology, Department of Medicine, University of Alberta, Alberta, Canada.,Mazankowski Alberta Heart Institute, University of Alberta, Alberta, Canada
| | - John R Ussher
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Alberta, Canada.,Cardiovascular Research Centre, University of Alberta, Alberta, Canada.,Women and Children's Health Research Institute, University of Alberta, Alberta, Canada
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3
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Gopal K, Al Batran R, Altamimi TR, Greenwell AA, Saed CT, Tabatabaei Dakhili SA, Dimaano MTE, Zhang Y, Eaton F, Sutendra G, Ussher JR. FoxO1 inhibition alleviates type 2 diabetes-related diastolic dysfunction by increasing myocardial pyruvate dehydrogenase activity. Cell Rep 2021; 35:108935. [PMID: 33826891 DOI: 10.1016/j.celrep.2021.108935] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 02/11/2021] [Accepted: 03/11/2021] [Indexed: 02/06/2023] Open
Abstract
Type 2 diabetes (T2D) increases the risk for diabetic cardiomyopathy and is characterized by diastolic dysfunction. Myocardial forkhead box O1 (FoxO1) activity is enhanced in T2D and upregulates pyruvate dehydrogenase (PDH) kinase 4 expression, which inhibits PDH activity, the rate-limiting enzyme of glucose oxidation. Because low glucose oxidation promotes cardiac inefficiency, we hypothesize that FoxO1 inhibition mitigates diabetic cardiomyopathy by stimulating PDH activity. Tissue Doppler echocardiography demonstrates improved diastolic function, whereas myocardial PDH activity is increased in cardiac-specific FoxO1-deficient mice subjected to experimental T2D. Pharmacological inhibition of FoxO1 with AS1842856 increases glucose oxidation rates in isolated hearts from diabetic C57BL/6J mice while improving diastolic function. However, AS1842856 treatment fails to improve diastolic function in diabetic mice with a cardiac-specific FoxO1 or PDH deficiency. Our work defines a fundamental mechanism by which FoxO1 inhibition improves diastolic dysfunction, suggesting that it may be an approach to alleviate diabetic cardiomyopathy.
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Affiliation(s)
- Keshav Gopal
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, Canada; Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada; Cardiovascular Research Centre, University of Alberta, Edmonton, AB, Canada
| | - Rami Al Batran
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, Canada; Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada; Cardiovascular Research Centre, University of Alberta, Edmonton, AB, Canada
| | - Tariq R Altamimi
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, Canada; Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada; Cardiovascular Research Centre, University of Alberta, Edmonton, AB, Canada
| | - Amanda A Greenwell
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, Canada; Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada; Cardiovascular Research Centre, University of Alberta, Edmonton, AB, Canada
| | - Christina T Saed
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, Canada; Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada; Cardiovascular Research Centre, University of Alberta, Edmonton, AB, Canada
| | - Seyed Amirhossein Tabatabaei Dakhili
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, Canada; Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada; Cardiovascular Research Centre, University of Alberta, Edmonton, AB, Canada
| | - M Toni E Dimaano
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, Canada
| | - Yongneng Zhang
- Cardiovascular Research Centre, University of Alberta, Edmonton, AB, Canada; Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - Farah Eaton
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, Canada; Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada; Cardiovascular Research Centre, University of Alberta, Edmonton, AB, Canada
| | - Gopinath Sutendra
- Cardiovascular Research Centre, University of Alberta, Edmonton, AB, Canada; Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - John R Ussher
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, Canada; Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada; Cardiovascular Research Centre, University of Alberta, Edmonton, AB, Canada.
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4
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McNally LA, Altamimi TR, Fulghum K, Hill BG. Considerations for using isolated cell systems to understand cardiac metabolism and biology. J Mol Cell Cardiol 2020; 153:26-41. [PMID: 33359038 DOI: 10.1016/j.yjmcc.2020.12.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [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] [Received: 07/31/2020] [Revised: 12/13/2020] [Accepted: 12/16/2020] [Indexed: 12/11/2022]
Abstract
Changes in myocardial metabolic activity are fundamentally linked to cardiac health and remodeling. Primary cardiomyocytes, induced pluripotent stem cell-derived cardiomyocytes, and transformed cardiomyocyte cell lines are common models used to understand how (patho)physiological conditions or stimuli contribute to changes in cardiac metabolism. These cell models are helpful also for defining metabolic mechanisms of cardiac dysfunction and remodeling. Although technical advances have improved our capacity to measure cardiomyocyte metabolism, there is often heterogeneity in metabolic assay protocols and cell models, which could hinder data interpretation and discernment of the mechanisms of cardiac (patho)physiology. In this review, we discuss considerations for integrating cardiomyocyte cell models with techniques that have become relatively common in the field, such as respirometry and extracellular flux analysis. Furthermore, we provide overviews of metabolic assays that complement XF analyses and that provide information on not only catabolic pathway activity, but biosynthetic pathway activity and redox status as well. Cultivating a more widespread understanding of the advantages and limitations of metabolic measurements in cardiomyocyte cell models will continue to be essential for the development of coherent metabolic mechanisms of cardiac health and pathophysiology.
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Affiliation(s)
- Lindsey A McNally
- Department of Medicine, Division of Environmental Medicine, Christina Lee Brown Envirome Institute, Diabetes and Obesity Center, University of Louisville, Louisville, KY, USA
| | - Tariq R Altamimi
- Department of Medicine, Division of Environmental Medicine, Christina Lee Brown Envirome Institute, Diabetes and Obesity Center, University of Louisville, Louisville, KY, USA
| | - Kyle Fulghum
- Department of Medicine, Division of Environmental Medicine, Christina Lee Brown Envirome Institute, Diabetes and Obesity Center, University of Louisville, Louisville, KY, USA
| | - Bradford G Hill
- Department of Medicine, Division of Environmental Medicine, Christina Lee Brown Envirome Institute, Diabetes and Obesity Center, University of Louisville, Louisville, KY, USA.
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5
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Altamimi TR, Audam TN, Zheng Y, Gibb A, Liu S, Jones SP, Hill BG. Abstract 517: Substrate Dependence of Mitochondrial Supercomplex Abundance in Murine Heart. Circ Res 2020. [DOI: 10.1161/res.127.suppl_1.517] [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
Mitochondrial supercomplexes are prominent in mammalian tissues that have high energy demand. Nevertheless, the mechanisms that regulate supercomplex formation and abundance remain unclear. In this study, we examined how myocardial fuel preference regulated by constitutive changes in phosphofructokinase (PFK) activity
in vivo
or by differential substrate provision to isolated mitochondria affect mitochondrial supercomplexes. Protein complexes from digitonin-solubilized cardiac mitochondria were resolved by blue-native polyacrylamide gel electrophoresis and were identified by mass spectrometry and immunoblotting to contain Complexes I, III, and IV as well as accessory proteins. Mitochondria from hearts with low PFK activity (Glyco
Lo
hearts) had higher mitochondrial supercomplex abundance and activity compared with mitochondria from wild-type (WT) or Glyco
Hi
hearts. Incubation of WT mitochondria with fatty acyl carnitine promoted higher supercomplex formation than did incubation with pyruvate, suggesting that substrate utilization is sufficient to regulate mitochondrial supercomplex abundance. These data are consistent with the hypothesis that mitochondrial supercomplex abundance is regulated in a substrate-dependent manner and suggest that metabolic scenarios favoring fat oxidation may promote supercomplex abundance.
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6
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Darwesh AM, Altamimi TR, Jamieson KL, Bassiouni W, Zhang H, Oudit GY, Lopaschuk GD, Seubert JM. Cytochrome P450‐Derived Epoxy Lipids of N‐3 PUFAs Protect the Heart From Ischemia‐Reperfusion Injury by Regulating Mitochondrial Sirtuin 3. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.03090] [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]
Affiliation(s)
| | | | | | | | - Hao Zhang
- Division of Cardiology, Department of Medicine
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7
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Altamimi TR, Gao S, Karwi QG, Fukushima A, Rawat S, Wagg CS, Zhang L, Lopaschuk GD. Adropin regulates cardiac energy metabolism and improves cardiac function and efficiency. Metabolism 2019; 98:37-48. [PMID: 31202835 DOI: 10.1016/j.metabol.2019.06.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 05/17/2019] [Accepted: 06/07/2019] [Indexed: 02/06/2023]
Abstract
BACKGROUND Impaired cardiac insulin signalling and high cardiac fatty acid oxidation rates are characteristics of conditions of insulin resistance and diabetic cardiomyopathies. The potential role of liver-derived peptides such as adropin in mediating these changes in cardiac energy metabolism is unclear, despite the fact that in skeletal muscle adropin can preferentially promote glucose metabolism and improve insulin sensitivity. OBJECTIVES To determine the influence of adropin on cardiac energy metabolism, insulin signalling and cardiac efficiency. METHODS C57Bl/6 mice were injected with either vehicle or a secretable form of adropin (450 nmol/kg, i.p.) three times over a 24-h period. The mice were fasted to accentuate the differences between animals in adropin plasma levels before their hearts were isolated and perfused using a working heart system. In addition, direct addition of adropin to the perfusate of ex vivo hearts isolated from non-fasting mice was utilized to investigate the acute effects of the peptide on heart metabolism and ex vivo function. RESULTS In contrast to the observed fasting-induced predominance of fatty acid oxidation as a source of ATP production in control hearts, insulin inhibition of fatty acid oxidation was preserved by adropin treatment. Adropin-treated mouse hearts also showed a higher cardiac work, which was accompanied by improved cardiac efficiency and enhanced insulin signalling compared to control hearts. Interestingly, acute adropin administration to isolated working hearts also resulted in an inhibition of fatty acid oxidation, accompanied by a robust stimulation of glucose oxidation compared to vehicle-treated hearts. Adropin also increased activation of downstream cardiac insulin signalling. Moreover, both in vivo and ex vivo treatment protocols induced a reduction in the inhibitory phosphorylation of pyruvate dehydrogenase (PDH), the major enzyme of glucose oxidation, and the protein levels of the responsible kinase PDH kinase 4 and the insulin-signalling inhibitory phosphorylation of JNK (p-T183/Y185) and IRS-1 (p-S307), suggesting acute receptor- and/or post-translational modification-mediated mechanisms. CONCLUSIONS These results demonstrate that adropin has important effects on energy metabolism in the heart and may be a putative candidate for the treatment of cardiac disease associated with impaired insulin sensitivity.
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Affiliation(s)
- Tariq R Altamimi
- Cardiovascular Research Centre, Department of Pediatrics, 423 Heritage Medical Research Building, University of Alberta, Edmonton, Alberta T6G 2S2, Canada
| | - Su Gao
- Cardiovascular Research Centre, Department of Pediatrics, 423 Heritage Medical Research Building, University of Alberta, Edmonton, Alberta T6G 2S2, Canada
| | - Qutuba G Karwi
- Cardiovascular Research Centre, Department of Pediatrics, 423 Heritage Medical Research Building, University of Alberta, Edmonton, Alberta T6G 2S2, Canada; Department of Pharmacology, College of Medicine, University of Diyala, Diyala, Iraq
| | - Arata Fukushima
- Department of Cardiovascular Medicine, Faculty of Medicine, Graduate School of Medicine, Hokkaido University, Kita-15, Nishi-7, Kita-ku, Sapporo 060-8638, Japan
| | - Sonia Rawat
- Cardiovascular Research Centre, Department of Pediatrics, 423 Heritage Medical Research Building, University of Alberta, Edmonton, Alberta T6G 2S2, Canada
| | - Cory S Wagg
- Cardiovascular Research Centre, Department of Pediatrics, 423 Heritage Medical Research Building, University of Alberta, Edmonton, Alberta T6G 2S2, Canada
| | - Liyan Zhang
- Cardiovascular Research Centre, Department of Pediatrics, 423 Heritage Medical Research Building, University of Alberta, Edmonton, Alberta T6G 2S2, Canada
| | - Gary D Lopaschuk
- Cardiovascular Research Centre, Department of Pediatrics, 423 Heritage Medical Research Building, University of Alberta, Edmonton, Alberta T6G 2S2, Canada.
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8
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Karwi QG, Zhang L, Altamimi TR, Wagg CS, Patel V, Uddin GM, Joerg AR, Padwal RS, Johnstone DE, Sharma A, Oudit GY, Lopaschuk GD. Weight loss enhances cardiac energy metabolism and function in heart failure associated with obesity. Diabetes Obes Metab 2019; 21:1944-1955. [PMID: 31050157 DOI: 10.1111/dom.13762] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [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: 03/12/2019] [Revised: 04/23/2019] [Accepted: 04/30/2019] [Indexed: 01/06/2023]
Abstract
AIMS Obesity is associated with high rates of cardiac fatty acid oxidation, low rates of glucose oxidation, cardiac hypertrophy and heart failure. Whether weight loss can lessen the severity of heart failure associated with obesity is not known. We therefore determined the effect of weight loss on cardiac energy metabolism and the severity of heart failure in obese mice with heart failure. MATERIALS AND METHODS Obesity and heart failure were induced by feeding mice a high-fat (HF) diet and subjecting them to transverse aortic constriction (TAC). Obese mice with heart failure were then switched for 8 weeks to either a low-fat (LF) diet (HF TAC LF) or caloric restriction (CR) (40% caloric intake reduction, HF TAC CR) to induce weight loss. RESULTS Weight loss improved cardiac function (%EF was 38 ± 6% and 36 ± 6% in HF TAC LF and HF TAC CR mice vs 25 ± 3% in HF TAC mice, P < 0.05) and it decreased cardiac hypertrophy post TAC (left ventricle mass was 168 ± 7 and 171 ± 10 mg in HF TAC LF and HF TAC CR mice, respectively, vs 210 ± 8 mg in HF TAC mice, P < 0.05). Weight loss enhanced cardiac insulin signalling, insulin-stimulated glucose oxidation rates (1.5 ± 0.1 and 1.5 ± 0.1 μmol/g dry wt/min in HF TAC LF and HF TAC CR mice, respectively, vs 0.2 ± 0.1 μmol/g dry wt/min in HF TAC mice, P < 0.05) and it decreased pyruvate dehydrogenase phosphorylation. Cardiac fatty acid oxidation rates, AMPKTyr172 /ACCSer79 signalling and the acetylation of ß-oxidation enzymes, were attenuated following weight loss. CONCLUSIONS Weight loss is an effective intervention to improve cardiac function and energy metabolism in heart failure associated with obesity.
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Affiliation(s)
- Qutuba G Karwi
- Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada
- Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada
- Department of Pharmacology, College of Medicine, University of Diyala, Diyala, Iraq
| | - Liyan Zhang
- Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada
- Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Tariq R Altamimi
- Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada
- Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Cory S Wagg
- Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada
- Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Vaibhav Patel
- Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada
- Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Golam M Uddin
- Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada
- Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Alice R Joerg
- Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada
- Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Raj S Padwal
- Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada
| | - David E Johnstone
- Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Arya Sharma
- Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Gavin Y Oudit
- Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada
- Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Gary D Lopaschuk
- Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada
- Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada
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9
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Altamimi TR, Karwi QG, Uddin GM, Fukushima A, Kwong JQ, Molkentin JD, Lopaschuk GD. Cardiac-specific deficiency of the mitochondrial calcium uniporter augments fatty acid oxidation and functional reserve. J Mol Cell Cardiol 2019; 127:223-231. [PMID: 30615880 DOI: 10.1016/j.yjmcc.2018.12.019] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2018] [Indexed: 11/24/2022]
Abstract
The mitochondrial calcium uniporter (MCU) relays cytosolic Ca2+ transients to the mitochondria. We examined whether energy metabolism was compromised in hearts from mice with a cardiac-specific deficiency of MCU subjected to an isoproterenol (ISO) challenge. Surprisingly, isolated working hearts from cardiac MCU-deficient mice showed higher cardiac work, both in the presence or absence of ISO. These hearts were not energy-starved, with ISO inducing a similar increase in glucose oxidation rates compared to control hearts, but a greater increase in fatty acid oxidation rates. This correlated with lower levels of the fatty acid oxidation inhibitor malonyl CoA, and to an increased stimulatory acetylation of its degrading enzyme malonyl CoA decarboxylase and of the fatty acid β-oxidation enzyme β-hydroxyacyl CoA dehydrogenase. We conclude that impaired mitochondrial Ca2+ uptake does not compromise cardiac energetics due to a compensatory stimulation of fatty acid oxidation that provides a higher energy reserve during acute adrenergic stress.
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Affiliation(s)
- Tariq R Altamimi
- Cardiovascular Translational Science Institute and the Department of Pediatrics, 423 Heritage Medical Research Building, University of Alberta, Edmonton, Alberta T6G 2S2, Canada
| | - Qutuba G Karwi
- Cardiovascular Translational Science Institute and the Department of Pediatrics, 423 Heritage Medical Research Building, University of Alberta, Edmonton, Alberta T6G 2S2, Canada
| | - Golam Mezbah Uddin
- Cardiovascular Translational Science Institute and the Department of Pediatrics, 423 Heritage Medical Research Building, University of Alberta, Edmonton, Alberta T6G 2S2, Canada
| | - Arata Fukushima
- Department of Cardiovascular Medicine, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Kita-15, Nishi-7, Kita-ku, Sapporo 060-8638, Japan
| | - Jennifer Q Kwong
- Howard Hughes Medical Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA 30322, USA
| | - Jeffery D Molkentin
- Howard Hughes Medical Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Gary D Lopaschuk
- Cardiovascular Translational Science Institute and the Department of Pediatrics, 423 Heritage Medical Research Building, University of Alberta, Edmonton, Alberta T6G 2S2, Canada.
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