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Piristine HC, May HI, Jiang N, Daou D, Olivares-Silva F, Elnwasany A, Szweda P, Szweda L, Kinter C, Kinter M, Sharma G, Wen X, Malloy CR, Jessen ME, Gillette TG, Hill JA. Afterload-induced Decreases in Fatty Acid Oxidation Develop Independently of Increased Glucose Utilization. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.09.17.613531. [PMID: 39345412 PMCID: PMC11429894 DOI: 10.1101/2024.09.17.613531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/01/2024]
Abstract
Background Metabolic substrate utilization in HFpEF (heart failure with preserved ejection fraction), the leading cause of heart failure worldwide, is pivotal to syndrome pathogenesis and yet remains ill defined. Under resting conditions, oxidation of free fatty acids (FFA) is the predominant energy source of the heart, supporting its unremitting contractile activity. In the context of disease-related stress, however, a shift toward greater reliance on glucose occurs. In the setting of obesity or diabetes, major contributors to HFpEF pathophysiology, the shift in metabolic substrate use toward glucose is impaired, sometimes attributed to the lower oxygen requirement of glucose oxidation versus fat metabolism. This notion, however, has never been tested conclusively. Furthermore, whereas oxygen demand increases in the setting of increased afterload, myocardial oxygen availability remains adequate for fatty acid oxidation (FAO). Therefore, a "preference" for glucose has been proposed. Methods and Results Pyruvate dehydrogenase complex (PDC) is the rate-limiting enzyme linking glycolysis to the TCA cycle. As PDK4 (PDC kinase 4) is up-regulated in HFpEF, we over-expressed PDK4 in cardiomyocytes, ensuring that PDC is phosphorylated and thereby inhibited. This leads to diminished use of pyruvate as energy substrate, mimicking the decline in glucose oxidation in HFpEF. Importantly, distinct from HFpEF-associated obesity, this model positioned us to abrogate the load-induced shift to glucose utilization in the absence of systemic high fat conditions. As expected, PDK4 transgenic mice manifested normal cardiac performance at baseline. However, they manifested a rapid and severe decline in contractile performance when challenged with modest increases in afterload triggered either by L-NAME or surgical transverse aortic constriction (TAC). This decline in function was not accompanied by an exacerbation of the myocardial hypertrophic growth response. Surprisingly, metabolic flux analysis revealed that, after TAC, fractional FAO decreased, even when glucose/pyruvate utilization was clamped at very low levels. Additionally, proteins involved in the transport and oxidation of FFA were paradoxically downregulated after TAC regardless of genotype. Conclusions These data demonstrate that cardiomyocytes in a setting in which glucose utilization is robustly diminished and prevented from increasing do not compensate for the deficit in glucose utilization by up-regulating FFA use.
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Visker JR, Cluntun AA, Velasco-Silva JN, Eberhardt DR, Cedeño-Rosario L, Shankar TS, Hamouche R, Ling J, Kwak H, Hillas JY, Aist I, Tseliou E, Navankasattusas S, Chaudhuri D, Ducker GS, Drakos SG, Rutter J. Enhancing mitochondrial pyruvate metabolism ameliorates ischemic reperfusion injury in the heart. JCI Insight 2024; 9:e180906. [PMID: 39052437 PMCID: PMC11385101 DOI: 10.1172/jci.insight.180906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Accepted: 07/19/2024] [Indexed: 07/27/2024] Open
Abstract
The clinical therapy for treating acute myocardial infarction is primary percutaneous coronary intervention (PPCI). PPCI is effective at reperfusing the heart; however, the rapid reintroduction of blood can cause ischemia-reperfusion (I/R). Reperfusion injury is responsible for up to half of the total myocardial damage, but there are no pharmacological interventions to reduce I/R. We previously demonstrated that inhibiting monocarboxylate transporter 4 (MCT4) and redirecting pyruvate toward oxidation can blunt hypertrophy. We hypothesized that this pathway might be important during I/R. Here, we establish that the pyruvate-lactate axis plays a role in determining myocardial salvage following injury. After I/R, the mitochondrial pyruvate carrier (MPC), required for pyruvate oxidation, is upregulated in the surviving myocardium. In cardiomyocytes lacking the MPC, there was increased cell death and less salvage after I/R, which was associated with an upregulation of MCT4. To determine the importance of pyruvate oxidation, we inhibited MCT4 with a small-molecule drug (VB124) at reperfusion. This strategy normalized reactive oxygen species (ROS), mitochondrial membrane potential (ΔΨ), and Ca2+, increased pyruvate entry to the TCA cycle, increased oxygen consumption, and improved myocardial salvage and functional outcomes following I/R. Our data suggest normalizing pyruvate-lactate metabolism by inhibiting MCT4 is a promising therapy to mitigate I/R injury.
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Affiliation(s)
- Joseph R Visker
- Nora Eccles Harrison Cardiovascular Research and Training Institute and
| | - Ahmad A Cluntun
- Department of Biochemistry, School of Medicine, University of Utah, Salt Lake City, Utah, USA
| | - Jesse N Velasco-Silva
- Department of Biochemistry, School of Medicine, University of Utah, Salt Lake City, Utah, USA
| | - David R Eberhardt
- Nora Eccles Harrison Cardiovascular Research and Training Institute and
| | - Luis Cedeño-Rosario
- Department of Biochemistry, School of Medicine, University of Utah, Salt Lake City, Utah, USA
| | | | - Rana Hamouche
- Nora Eccles Harrison Cardiovascular Research and Training Institute and
| | - Jing Ling
- Nora Eccles Harrison Cardiovascular Research and Training Institute and
| | - Hyoin Kwak
- Nora Eccles Harrison Cardiovascular Research and Training Institute and
| | - J Yanni Hillas
- Nora Eccles Harrison Cardiovascular Research and Training Institute and
| | - Ian Aist
- Nora Eccles Harrison Cardiovascular Research and Training Institute and
| | - Eleni Tseliou
- Nora Eccles Harrison Cardiovascular Research and Training Institute and
- Division of Cardiovascular Medicine, Department of Internal Medicine, School of Medicine, Salt Lake City, Utah, USA
| | | | - Dipayan Chaudhuri
- Nora Eccles Harrison Cardiovascular Research and Training Institute and
- Department of Biochemistry, School of Medicine, University of Utah, Salt Lake City, Utah, USA
- Division of Cardiovascular Medicine, Department of Internal Medicine, School of Medicine, Salt Lake City, Utah, USA
- Department of Biomedical Engineering, School of Medicine, University of Utah, Salt Lake City, Utah, USA
| | - Gregory S Ducker
- Department of Biochemistry, School of Medicine, University of Utah, Salt Lake City, Utah, USA
| | - Stavros G Drakos
- Nora Eccles Harrison Cardiovascular Research and Training Institute and
- Division of Cardiovascular Medicine, Department of Internal Medicine, School of Medicine, Salt Lake City, Utah, USA
- Department of Biomedical Engineering, School of Medicine, University of Utah, Salt Lake City, Utah, USA
| | - Jared Rutter
- Department of Biochemistry, School of Medicine, University of Utah, Salt Lake City, Utah, USA
- Howard Hughes Medical Institute, Chevy Chase, Maryland, USA
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Naeem F, Leone TC, Petucci C, Shoffler C, Kodihalli RC, Hidalgo T, Tow-Keogh C, Mancuso J, Tzameli I, Bennett D, Groarke JD, Flach RJR, Rader DJ, Kelly DP. Targeted Quantitative Plasma Metabolomics Identifies Metabolite Signatures that Distinguish Heart Failure with Reduced and Preserved Ejection Fraction. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.07.24.24310961. [PMID: 39108509 PMCID: PMC11302718 DOI: 10.1101/2024.07.24.24310961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 08/12/2024]
Abstract
Background Two general phenotypes of heart failure (HF) are recognized: HF with reduced ejection fraction (HFrEF) and with preserved EF (HFpEF). To develop HF disease phenotype-specific approaches to define and guide treatment, distinguishing biomarkers are needed. The goal of this study was to utilize quantitative metabolomics on a large, diverse population to replicate and extend existing knowledge of the plasma metabolic signatures in human HF. Methods Quantitative, targeted LC/MS plasma metabolomics was conducted on 787 samples collected by the Penn Medicine BioBank from subjects with HFrEF (n=219), HFpEF (n=357), and matched non-failing Controls (n=211). A total of 90 metabolites were analyzed, comprising 28 amino acids, 8 organic acids, and 54 acylcarnitines. 733 of these samples were also processed via an OLINK protein panel for proteomic profiling. Results Consistent with previous studies, unsaturated forms of medium/long chain acylcarnitines were elevated in the HFrEF group to a greater extent than the HFpEF group compared to Controls. A number of amino acid derivatives, including 1- and 3-methylhistidine, homocitrulline, and symmetric (SDMA) and asymmetric (ADMA) dimethylarginine were elevated in HF, with ADMA elevated uniquely in HFpEF. Plasma branched-chain amino acids (BCAA) were not different across the groups; however, short-chain acylcarnitine species indicative of BCAA catabolism were significantly elevated in both HF groups. The ketone body 3-hydroxybutyrate (3-HBA) and its metabolite C4-OH carnitine were uniquely elevated in the HFrEF group. Linear regression models demonstrated a significant correlation between plasma 3-HBA and NT-proBNP in both forms of HF, stronger in HFrEF. Conclusions These results identify plasma signatures that are shared as well as potentially distinguish between HFrEF and HFpEF. Metabolite markers for ketogenic metabolic reprogramming in extra-cardiac tissues were identified as unique signatures in the HFrEF group, possibly related to the lipolytic action of increased levels of BNP. Future studies will be necessary to further validate these metabolites as HF biosignatures that may guide phenotype-specific therapeutics and provide insight into the systemic metabolic responses to HFpEF and HFrEF.
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Affiliation(s)
- Fawaz Naeem
- Cardiovascular Institute, Department of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Teresa C. Leone
- Cardiovascular Institute, Department of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Christopher Petucci
- Cardiovascular Institute, Department of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Clarissa Shoffler
- Cardiovascular Institute, Department of Medicine, University of Pennsylvania, Philadelphia, PA
| | | | | | | | | | | | | | | | | | - Daniel J. Rader
- Cardiovascular Institute, Department of Medicine, University of Pennsylvania, Philadelphia, PA
- Cardiovascular Institute, Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Daniel P. Kelly
- Cardiovascular Institute, Department of Medicine, University of Pennsylvania, Philadelphia, PA
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Thorp EB, Karlstaedt A. Intersection of Immunology and Metabolism in Myocardial Disease. Circ Res 2024; 134:1824-1840. [PMID: 38843291 DOI: 10.1161/circresaha.124.323660] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Accepted: 04/15/2024] [Indexed: 06/12/2024]
Abstract
Immunometabolism is an emerging field at the intersection of immunology and metabolism. Immune cell activation plays a critical role in the pathogenesis of cardiovascular diseases and is integral for regeneration during cardiac injury. We currently possess a limited understanding of the processes governing metabolic interactions between immune cells and cardiomyocytes. The impact of this intercellular crosstalk can manifest as alterations to the steady state flux of metabolites and impact cardiac contractile function. Although much of our knowledge is derived from acute inflammatory response, recent work emphasizes heterogeneity and flexibility in metabolism between cardiomyocytes and immune cells during pathological states, including ischemic, cardiometabolic, and cancer-associated disease. Metabolic adaptation is crucial because it influences immune cell activation, cytokine release, and potential therapeutic vulnerabilities. This review describes current concepts about immunometabolic regulation in the heart, focusing on intercellular crosstalk and intrinsic factors driving cellular regulation. We discuss experimental approaches to measure the cardio-immunologic crosstalk, which are necessary to uncover unknown mechanisms underlying the immune and cardiac interface. Deeper insight into these axes holds promise for therapeutic strategies that optimize cardioimmunology crosstalk for cardiac health.
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Affiliation(s)
- Edward B Thorp
- Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, IL (E.B.T.)
| | - Anja Karlstaedt
- Department of Cardiology, Smidt Heart Institute, Cedars Sinai Medical Center, Los Angeles, CA (A.K.)
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5
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Visker JR, Leszczynski EC, Wellette-Hunsucker AG, McPeek AC, Quinn MA, Kim SH, Bazil JN, Ferguson DP. Postnatal growth restriction alters myocardial mitochondrial energetics in mice. Exp Physiol 2024; 109:562-575. [PMID: 38180279 PMCID: PMC10984791 DOI: 10.1113/ep091304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 12/14/2023] [Indexed: 01/06/2024]
Abstract
Postnatal growth restriction (PGR) can increase the risk of cardiovascular disease (CVD) potentially due to impairments in oxidative phosphorylation (OxPhos) within cardiomyocyte mitochondria. The purpose of this investigation was to determine if PGR impairs cardiac metabolism, specifically OxPhos. FVB (Friend Virus B-type) mice were fed a normal-protein (NP: 20% protein), or low-protein (LP: 8% protein) isocaloric diet 2 weeks before mating. LP dams produce ∼20% less milk, and pups nursed by LP dams experience reduced growth into adulthood as compared to pups nursed by NP dams. At birth (PN1), pups born to dams fed the NP diet were transferred to LP dams (PGR group) or a different NP dam (control group: CON). At weaning (PN21), all mice were fed the NP diet. At PN22 and PN80, mitochondria were isolated for respirometry (oxygen consumption rate,J O 2 ${J_{{{\mathrm{O}}_{\mathrm{2}}}}}$ ) and fluorimetry (reactive oxygen species emission,J H 2 O 2 ${J_{{{\mathrm{H}}_{\mathrm{2}}}{{\mathrm{O}}_{\mathrm{2}}}}}$ ) analysis measured as baseline respiration (LEAK) and with saturating ADP (OxPhos). Western blotting at PN22 and PN80 determined protein abundance of uncoupling protein 3, peroxiredoxin-6, voltage-dependent anion channel and adenine nucleotide translocator 1 to provide further insight into mitochondrial function. ANOVAs with the main effects of diet, sex and age with α-level of 0.05 was set a priori. Overall, PGR (7.8 ± 1.1) had significant (P = 0.01) reductions in respiratory control in complex I when compared to CON (8.9 ± 1.0). In general, our results show that PGR led to higher electron leakage in the form of free radical production and reactive oxygen species emission. No significant diet effects were found in protein abundance. The observed reduced respiratory control and increased ROS emission in PGR mice may increase risk for CVD in mice.
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Affiliation(s)
- Joseph R Visker
- The Nora Eccles Harrison Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, Utah, USA
- Department of Kinesiology, Michigan State University, East Lansing, Michigan, USA
| | - Eric C Leszczynski
- Department of Kinesiology, Michigan State University, East Lansing, Michigan, USA
| | - Austin G Wellette-Hunsucker
- Department of Kinesiology, Michigan State University, East Lansing, Michigan, USA
- Department of Physiology, University of Kentucky, Lexington, Kentucky, USA
| | - Ashley C McPeek
- Department of Kinesiology, Michigan State University, East Lansing, Michigan, USA
| | - Melissa A Quinn
- Department of Kinesiology, Michigan State University, East Lansing, Michigan, USA
| | - Seong Hyun Kim
- Department of Kinesiology, Michigan State University, East Lansing, Michigan, USA
| | - Jason N Bazil
- Department of Physiology, Michigan State University, East Lansing, Michigan, USA
| | - David P Ferguson
- Department of Kinesiology, Michigan State University, East Lansing, Michigan, USA
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6
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Visker JR, Cluntun AA, Velasco-Silva JN, Eberhardt DR, Shankar TS, Hamouche R, Ling J, Kwak H, Hillas Y, Aist I, Tseliou E, Navankasattusas S, Chaudhuri D, Ducker GS, Drakos SG, Rutter J. Enhancing mitochondrial pyruvate metabolism ameliorates myocardial ischemic reperfusion injury. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.01.577463. [PMID: 38352459 PMCID: PMC10862804 DOI: 10.1101/2024.02.01.577463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/03/2024]
Abstract
The established clinical therapy for the treatment of acute myocardial infarction is primary percutaneous coronary intervention (PPCI) to restore blood flow to the ischemic myocardium. PPCI is effective at reperfusing the ischemic myocardium, however the rapid re-introduction of oxygenated blood also can cause ischemia-reperfusion (I/R) injury. Reperfusion injury is the culprit for up to half of the final myocardial damage, but there are no clinical interventions to reduce I/R injury. We previously demonstrated that inhibiting the lactate exporter, monocarboxylate transporter 4 (MCT4), and re-directing pyruvate towards oxidation can blunt isoproterenol-induced hypertrophy. Based on this finding, we hypothesized that the same pathway might be important during I/R. Here, we establish that the pyruvate-lactate metabolic axis plays a critical role in determining myocardial salvage following injury. Post-I/R injury, the mitochondrial pyruvate carrier (MPC), required for pyruvate oxidation, is upregulated in the surviving myocardium following I/R injury. MPC loss in cardiomyocytes caused more cell death with less myocardial salvage, which was associated with an upregulation of MCT4 in the myocardium at risk of injury. We deployed a pharmacological strategy of MCT4 inhibition with a highly selective compound (VB124) at the time of reperfusion. This strategy normalized reactive oxygen species (ROS), mitochondrial membrane potential (Δψ), and Ca 2+ , increased pyruvate entry to TCA cycle, and improved myocardial salvage and functional outcomes following I/R injury. Altogether, our data suggest that normalizing the pyruvate-lactate metabolic axis via MCT4 inhibition is a promising pharmacological strategy to mitigate I/R injury. GRAPHICAL ABSTRACT
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7
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Wei J, Duan X, Chen J, Zhang D, Xu J, Zhuang J, Wang S. Metabolic adaptations in pressure overload hypertrophic heart. Heart Fail Rev 2024; 29:95-111. [PMID: 37768435 DOI: 10.1007/s10741-023-10353-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/19/2023] [Indexed: 09/29/2023]
Abstract
This review article offers a detailed examination of metabolic adaptations in pressure overload hypertrophic hearts, a condition that plays a pivotal role in the progression of heart failure with preserved ejection fraction (HFpEF) to heart failure with reduced ejection fraction (HFrEF). The paper delves into the complex interplay between various metabolic pathways, including glucose metabolism, fatty acid metabolism, branched-chain amino acid metabolism, and ketone body metabolism. In-depth insights into the shifts in substrate utilization, the role of different transporter proteins, and the potential impact of hypoxia-induced injuries are discussed. Furthermore, potential therapeutic targets and strategies that could minimize myocardial injury and promote cardiac recovery in the context of pressure overload hypertrophy (POH) are examined. This work aims to contribute to a better understanding of metabolic adaptations in POH, highlighting the need for further research on potential therapeutic applications.
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Affiliation(s)
- Jinfeng Wei
- Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, China
| | - Xuefei Duan
- Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, China
| | - Jiaying Chen
- Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, China
| | - Dengwen Zhang
- Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, China
| | - Jindong Xu
- Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, China
| | - Jian Zhuang
- Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, China.
| | - Sheng Wang
- Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, China.
- Beijing Anzhen Hospital, Capital Medical University, Beijing, China.
- Linzhi People's Hospital, Linzhi, Tibet, China.
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8
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Gao F, Liang T, Lu YW, Pu L, Fu X, Dong X, Hong T, Zhang F, Liu N, Zhou Y, Wang H, Liang P, Guo Y, Yu H, Zhu W, Hu X, Chen H, Zhou B, Pu WT, Mably JD, Wang J, Wang DZ, Chen J. Reduced Mitochondrial Protein Translation Promotes Cardiomyocyte Proliferation and Heart Regeneration. Circulation 2023; 148:1887-1906. [PMID: 37905452 PMCID: PMC10841688 DOI: 10.1161/circulationaha.122.061192] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 10/03/2023] [Indexed: 11/02/2023]
Abstract
BACKGROUND The importance of mitochondria in normal heart function are well recognized and recent studies have implicated changes in mitochondrial metabolism with some forms of heart disease. Previous studies demonstrated that knockdown of the mitochondrial ribosomal protein S5 (MRPS5) by small interfering RNA (siRNA) inhibits mitochondrial translation and thereby causes a mitonuclear protein imbalance. Therefore, we decided to examine the effects of MRPS5 loss and the role of these processes on cardiomyocyte proliferation. METHODS We deleted a single allele of MRPS5 in mice and used left anterior descending coronary artery ligation surgery to induce myocardial damage in these animals. We examined cardiomyocyte proliferation and cardiac regeneration both in vivo and in vitro. Doxycycline treatment was used to inhibit protein translation. Heart function in mice was assessed by echocardiography. Quantitative real-time polymerase chain reaction and RNA sequencing were used to assess changes in transcription and chromatin immunoprecipitation (ChIP) and BioChIP were used to assess chromatin effects. Protein levels were assessed by Western blotting and cell proliferation or death by histology and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assays. Adeno-associated virus was used to overexpress genes. The luciferase reporter assay was used to assess promoter activity. Mitochondrial oxygen consumption rate, ATP levels, and reactive oxygen species were also analyzed. RESULTS We determined that deletion of a single allele of MRPS5 in mice results in elevated cardiomyocyte proliferation and cardiac regeneration; this observation correlates with improved cardiac function after induction of myocardial infarction. We identified ATF4 (activating transcription factor 4) as a key regulator of the mitochondrial stress response in cardiomyocytes from Mrps5+/- mice; furthermore, ATF4 regulates Knl1 (kinetochore scaffold 1) leading to an increase in cytokinesis during cardiomyocyte proliferation. The increased cardiomyocyte proliferation observed in Mrps5+/- mice was attenuated when one allele of Atf4 was deleted genetically (Mrps5+/-/Atf4+/-), resulting in the loss in the capacity for cardiac regeneration. Either MRPS5 inhibition (or as we also demonstrate, doxycycline treatment) activate a conserved regulatory mechanism that increases the proliferation of human induced pluripotent stem cell-derived cardiomyocytes. CONCLUSIONS These data highlight a critical role for MRPS5/ATF4 in cardiomyocytes and an exciting new avenue of study for therapies to treat myocardial injury.
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Affiliation(s)
- Feng Gao
- Department of Cardiology, State Key Laboratory of Transvascular Implantation Devices, Provincial Key Lab of Cardiovascular Research, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, China
- Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou 310029, China
| | - Tian Liang
- Department of Cardiology, State Key Laboratory of Transvascular Implantation Devices, Provincial Key Lab of Cardiovascular Research, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, China
- Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou 310029, China
| | - Yao Wei Lu
- Department of Cardiology, Boston Children’s Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Linbin Pu
- Department of Cardiology, State Key Laboratory of Transvascular Implantation Devices, Provincial Key Lab of Cardiovascular Research, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, China
- Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou 310029, China
| | - Xuyang Fu
- Department of Cardiology, State Key Laboratory of Transvascular Implantation Devices, Provincial Key Lab of Cardiovascular Research, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, China
- Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou 310029, China
| | - Xiaoxuan Dong
- Department of Cardiology, State Key Laboratory of Transvascular Implantation Devices, Provincial Key Lab of Cardiovascular Research, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, China
- Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou 310029, China
| | - Tingting Hong
- Department of Cardiology, State Key Laboratory of Transvascular Implantation Devices, Provincial Key Lab of Cardiovascular Research, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, China
| | - Feng Zhang
- Department of Cardiology, State Key Laboratory of Transvascular Implantation Devices, Provincial Key Lab of Cardiovascular Research, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, China
- Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou 310029, China
| | - Ning Liu
- Department of Cardiology, State Key Laboratory of Transvascular Implantation Devices, Provincial Key Lab of Cardiovascular Research, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, China
- Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou 310029, China
| | - Yuxia Zhou
- Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou 310029, China
| | - Hongkun Wang
- Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou 310029, China
- Key Laboratory of combined Multi-organ Transplantation, Ministry of Public Health, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, 310003, China
| | - Ping Liang
- Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou 310029, China
- Key Laboratory of combined Multi-organ Transplantation, Ministry of Public Health, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, 310003, China
| | - Yuxuan Guo
- Institute of Cardiovascular Sciences, Peking University Health Science Center, 38 Xueyuan Road, Beijing, 100092 China
| | - Hong Yu
- Department of Cardiology, State Key Laboratory of Transvascular Implantation Devices, Provincial Key Lab of Cardiovascular Research, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, China
| | - Wei Zhu
- Department of Cardiology, State Key Laboratory of Transvascular Implantation Devices, Provincial Key Lab of Cardiovascular Research, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, China
| | - Xinyang Hu
- Department of Cardiology, State Key Laboratory of Transvascular Implantation Devices, Provincial Key Lab of Cardiovascular Research, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, China
| | - Hong Chen
- Vascular Biology Program, Boston Children’s Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Bin Zhou
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, China
| | - William T Pu
- Department of Cardiology, Boston Children’s Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| | - John D. Mably
- Center for Regenerative Medicine, University of South Florida Health Heart Institute, Departments of Internal Medicine and Molecular Pharmacology and Physiology, Morsani School of Medicine, University of South Florida, Tampa, FL 33602, USA
| | - Jian’an Wang
- Department of Cardiology, State Key Laboratory of Transvascular Implantation Devices, Provincial Key Lab of Cardiovascular Research, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, China
| | - Da-Zhi Wang
- Department of Cardiology, Boston Children’s Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
- Center for Regenerative Medicine, University of South Florida Health Heart Institute, Departments of Internal Medicine and Molecular Pharmacology and Physiology, Morsani School of Medicine, University of South Florida, Tampa, FL 33602, USA
| | - Jinghai Chen
- Department of Cardiology, State Key Laboratory of Transvascular Implantation Devices, Provincial Key Lab of Cardiovascular Research, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, China
- Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou 310029, China
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9
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Owesny P, Grune T. The link between obesity and aging - insights into cardiac energy metabolism. Mech Ageing Dev 2023; 216:111870. [PMID: 37689316 DOI: 10.1016/j.mad.2023.111870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 09/04/2023] [Accepted: 09/06/2023] [Indexed: 09/11/2023]
Abstract
Obesity and aging are well-established risk factors for a range of diseases, including cardiovascular diseases and type 2 diabetes. Given the escalating prevalence of obesity, the aging population, and the subsequent increase in cardiovascular diseases, it is crucial to investigate the underlying mechanisms involved. Both aging and obesity have profound effects on the energy metabolism through various mechanisms, including metabolic inflexibility, altered substrate utilization for energy production, deregulated nutrient sensing, and mitochondrial dysfunction. In this review, we aim to present and discuss the hypothesis that obesity, due to its similarity in changes observed in the aging heart, may accelerate the process of cardiac aging and exacerbate the clinical outcomes of elderly individuals with obesity.
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Affiliation(s)
- Patricia Owesny
- Department of Molecular Toxicology, German Institute of Human Nutrition Potsdam-Rehbruecke, Nuthetal, Germany; DZHK (German Center for Cardiovascular Research), partner site Berlin, Berlin, Germany
| | - Tilman Grune
- Department of Molecular Toxicology, German Institute of Human Nutrition Potsdam-Rehbruecke, Nuthetal, Germany; DZHK (German Center for Cardiovascular Research), partner site Berlin, Berlin, Germany; German Center for Diabetes Research (DZD), München-Neuherberg, Germany.
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10
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Renaud D, Scholl-Bürgi S, Karall D, Michel M. Comparative Metabolomics in Single Ventricle Patients after Fontan Palliation: A Strong Case for a Targeted Metabolic Therapy. Metabolites 2023; 13:932. [PMID: 37623876 PMCID: PMC10456471 DOI: 10.3390/metabo13080932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 07/28/2023] [Accepted: 08/03/2023] [Indexed: 08/26/2023] Open
Abstract
Most studies on single ventricle (SV) circulation take a physiological or anatomical approach. Although there is a tight coupling between cardiac contractility and metabolism, the metabolic perspective on this patient population is very recent. Early findings point to major metabolic disturbances, with both impaired glucose and fatty acid oxidation in the cardiomyocytes. Additionally, Fontan patients have systemic metabolic derangements such as abnormal glucose metabolism and hypocholesterolemia. Our literature review compares the metabolism of patients with a SV circulation after Fontan palliation with that of patients with a healthy biventricular (BV) heart, or different subtypes of a failing BV heart, by Pubmed review of the literature on cardiac metabolism, Fontan failure, heart failure (HF), ketosis, metabolism published in English from 1939 to 2023. Early evidence demonstrates that SV circulation is not only a hemodynamic burden requiring staged palliation, but also a metabolic issue with alterations similar to what is known for HF in a BV circulation. Alterations of fatty acid and glucose oxidation were found, resulting in metabolic instability and impaired energy production. As reported for patients with BV HF, stimulating ketone oxidation may be an effective treatment strategy for HF in these patients. Few but promising clinical trials have been conducted thus far to evaluate therapeutic ketosis with HF using a variety of instruments, including ketogenic diet, ketone esters, and sodium-glucose co-transporter-2 (SGLT2) inhibitors. An initial trial on a small cohort demonstrated favorable outcomes for Fontan patients treated with SGLT2 inhibitors. Therapeutic ketosis is worth considering in the treatment of Fontan patients, as ketones positively affect not only the myocardial energy metabolism, but also the global Fontan physiopathology. Induced ketosis seems promising as a concerted therapeutic strategy.
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Affiliation(s)
- David Renaud
- Fundamental and Biomedical Sciences, Paris-Cité University, 75006 Paris, France
- Health Sciences Faculty, Universidad Europea Miguel de Cervantes, 47012 Valladolid, Spain
- Fundacja Recover, 05-124 Skrzeszew, Poland
| | - Sabine Scholl-Bürgi
- Department of Child and Adolescent Health, Division of Pediatrics I—Inherited Metabolic Disorders, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Daniela Karall
- Department of Child and Adolescent Health, Division of Pediatrics I—Inherited Metabolic Disorders, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Miriam Michel
- Department of Child and Adolescent Health, Division of Pediatrics III—Cardiology, Pulmonology, Allergology and Cystic Fibrosis, Medical University of Innsbruck, 6020 Innsbruck, Austria
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11
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Guo Y, Wen J, He A, Qu C, Peng Y, Luo S, Wang X. iNOS contributes to heart failure with preserved ejection fraction through mitochondrial dysfunction and Akt S-nitrosylation. J Adv Res 2023; 43:175-186. [PMID: 36585107 PMCID: PMC9811328 DOI: 10.1016/j.jare.2022.03.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Accepted: 03/02/2022] [Indexed: 01/07/2023] Open
Abstract
INTRODUCTION Despite the high morbidity and mortality of heart failure with preserved fraction (HFpEF), there are currently no effective therapies for this condition. Moreover, the pathophysiological basis of HFpEF remains poorly understood. OBJECTIVE The aim of the present study was to investigate the role of inducible nitric oxide synthase (iNOS) and its underlying mechanism in a high-fat diet and Nω-nitro-L-arginine methyl ester-induced HFpEF mouse model. METHODS The selective iNOS inhibitor L-NIL was used to examine the effects of short-term iNOS inhibition, whereas the long-term effects of iNOS deficiency were evaluated using iNOS-null mice. Cardiac and mitochondrial function, oxidative stress and Akt S-nitrosylation were then measured. RESULTS The results demonstrated that both pharmacological inhibition and iNOS knockout mitigated mitochondrial dysfunction, oxidative stress and Akt S-nitrosylation, leading to an ameliorated HFpEF phenotype in mice. In vitro, iNOS directly induced Akt S-nitrosylation at cysteine 224 residues , leading to oxidative stress, while inhibiting insulin-mediated glucose uptake in myocytes. CONCLUSION Altogether, the present findings suggested an important role for iNOS in the pathophysiological development of HFpEF, indicating that iNOS inhibition may represent a potential therapeutic strategy for HFpEF.
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Affiliation(s)
- Yongzheng Guo
- Division of Cardiology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - Junjie Wen
- Division of Cardiology, West China Guang'an Hospital of Sichan University, Guang'an 638500, China
| | - An He
- Division of Cardiology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - Can Qu
- Department of Pharmacy, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - Yuce Peng
- Division of Cardiology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - Suxin Luo
- Division of Cardiology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China.
| | - Xiaowen Wang
- Department of Cardiothoracic Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China.
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12
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Wang L, Wu L, Fu Y, Jiang L, Huang Z, Yang Z, Fang X. Changes of Key Rate-Limiting Enzyme Activity in Glucose Metabolism After Cardiopulmonary Resuscitation. Shock 2022; 57:576-582. [PMID: 34731097 DOI: 10.1097/shk.0000000000001884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES To investigate the activity of key rate-limiting enzymes of glucose metabolism after restoration of spontaneous circulation (ROSC), to explore the potential pathophysiological mechanism of impaired myocardial energy metabolism after cardiopulmonary resuscitation (CPR). METHODS Twenty-one male Sprague-Dawley rats were randomized into three experimental groups assigned in accordance with different observation times after ROSC: Sham, instrumented rats without induced cardiac arrest or resuscitation; post-resuscitation (PR2 h); PR24 h. In these groups, CPR, including precordial compressions and synchronized mechanical ventilation, was initiated 6 min after asphyxia-induced cardiac arrest. Hearts were harvested after ROSC and samples were used to detect high-energy phosphate and glucose metabolic enzyme activity. RESULTS Compared with sham, the contents of phosphocreatine and adenosine triphosphate reduced in the PR2 h group, while remained unchanged in the PR24 h group. Activities of hexokinase and pyruvate kinase did not change after ROSC. Phosphofructokinase activity decreased only in the PR24 h group. Activities of pyruvate dehydrogenase and citrate synthase fell in PR2 h group and recovered in the PR24 h group. However, isocitrate dehydrogenase and α-ketoglutarate dehydrogenase activities fell in the PR2 h group, but did not recover in the PR24 h group. CONCLUSIONS Lowered key rate-limiting enzymes activity in glucose metabolism resulted in impairment of energy production in the early stage of ROSC, but partially recovered in 24 h. This process has a role in the mechanism of impaired myocardial energy metabolism after CPR. This investigation might shed light on new strategies to treat post resuscitation myocardial dysfunction.
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Affiliation(s)
- Liwen Wang
- Department of Emergency Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China
- Institute of Cardiopulmonary Cerebral Resuscitation, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Liangliang Wu
- Department of Emergency Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China
- Institute of Cardiopulmonary Cerebral Resuscitation, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Yue Fu
- Institute of Cardiopulmonary Cerebral Resuscitation, Sun Yat-sen University, Guangzhou, Guangdong, China
- Department of Emergency Medicine, The First People's Hospital of Foshan, Foshan, Guangdong, China
| | - Longyuan Jiang
- Department of Emergency Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China
- Institute of Cardiopulmonary Cerebral Resuscitation, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Zitong Huang
- Department of Emergency Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China
- Institute of Cardiopulmonary Cerebral Resuscitation, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Zhengfei Yang
- Department of Emergency Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China
- Institute of Cardiopulmonary Cerebral Resuscitation, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Xiangshao Fang
- Department of Emergency Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China
- Institute of Cardiopulmonary Cerebral Resuscitation, Sun Yat-sen University, Guangzhou, Guangdong, China
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13
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Heart Failure and Drug Therapies: A Metabolic Review. Int J Mol Sci 2022; 23:ijms23062960. [PMID: 35328390 PMCID: PMC8950643 DOI: 10.3390/ijms23062960] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 03/01/2022] [Accepted: 03/01/2022] [Indexed: 02/07/2023] Open
Abstract
Cardiovascular disease is the leading cause of mortality globally with at least 26 million people worldwide living with heart failure (HF). Metabolism has been an active area of investigation in the setting of HF since the heart demands a high rate of ATP turnover to maintain homeostasis. With the advent of -omic technologies, specifically metabolomics and lipidomics, HF pathologies have been better characterized with unbiased and holistic approaches. These techniques have identified novel pathways in our understanding of progression of HF and potential points of intervention. Furthermore, sodium-glucose transport protein 2 inhibitors, a drug that has changed the dogma of HF treatment, has one of the strongest types of evidence for a potential metabolic mechanism of action. This review will highlight cardiac metabolism in both the healthy and failing heart and then discuss the metabolic effects of heart failure drugs.
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14
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Oluranti OI, Agboola EA, Fubara NE, Ajayi MO, Michael OS. Cadmium exposure induces cardiac glucometabolic dysregulation and lipid accumulation independent of pyruvate dehydrogenase activity. Ann Med 2021; 53:1108-1117. [PMID: 34259114 PMCID: PMC8280890 DOI: 10.1080/07853890.2021.1947519] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 06/20/2021] [Indexed: 02/01/2023] Open
Abstract
CONTEXT Suppressed glucose metabolism, elevated fatty acid metabolism and lipid deposition within myocardial cells are the key pathological features of diabetic cardiomyopathy. Studies have associated cadmium exposure with metabolic disturbances. OBJECTIVE To examine the effects of cadmium exposure on cardiac glucose homeostasis and lipid accumulation in male Wistar rats. METHODS Male Wistar rats were treated for 21 days as (n = 5): Control, cadmium chloride Cd5 (5 mg/kg, p.o.), cadmium chloride Cd30 (30 mg/kg, p.o). RESULTS The fasting serum insulin level in this study decreased significantly. Pyruvate and hexokinase activity reduced significantly in the Cd5 group while no significant change in lactate and glycogen levels. The activity of pyruvate dehydrogenase enzyme significantly increased with an increasing dosage of cadmium. The free fatty acid, total cholesterol and triglyceride levels in the heart increased significantly with increasing dosage of cadmium when compared with the control. Lipoprotein lipase activity in the heart showed no difference in the Cd5 group but a reduction in the activity in the Cd30 group was observed. CONCLUSION This study indicates that cadmium exposure interferes with cardiac substrate handling resulting in impaired glucometabolic regulation and lipid accumulation which could reduce cardiac efficiency.
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Affiliation(s)
- Olufemi I. Oluranti
- Applied and Environmental Research Unit, Department of Physiology, College of Health Sciences, Bowen University, Iwo, Nigeria
| | - Ebunoluwa A. Agboola
- Applied and Environmental Research Unit, Department of Physiology, College of Health Sciences, Bowen University, Iwo, Nigeria
| | - Nteimam E. Fubara
- Applied and Environmental Research Unit, Department of Physiology, College of Health Sciences, Bowen University, Iwo, Nigeria
| | - Mercy O. Ajayi
- Applied and Environmental Research Unit, Department of Physiology, College of Health Sciences, Bowen University, Iwo, Nigeria
| | - Olugbenga S. Michael
- Cardiometabolic Research Unit, Department of Physiology, College of Health Sciences, Bowen University, Iwo, Nigeria
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15
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Desai MS. Mechanistic insights into the pathophysiology of cirrhotic cardiomyopathy. Anal Biochem 2021; 636:114388. [PMID: 34587512 DOI: 10.1016/j.ab.2021.114388] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 08/22/2021] [Accepted: 09/15/2021] [Indexed: 02/08/2023]
Abstract
Myocardial dysfunction in end stage cirrhotic liver disease, termed cirrhotic cardiomyopathy, is a long known, but little understood comorbidity seen in ∼50% of adults and children who present for liver transplantation. Structural, functional, hemodynamic and electrocardiographic aberrations that occur in the heart as a direct consequence of a damaged liver, is associated with multi-organ failure and increased mortality and morbidity in patients undergoing surgical procedures such as porto-systemic shunt placement and liver transplantation. Despite its clinical significance and rapid advances in science and pharmacotherapy, there is yet no specific treatment for this disease. This may be due to a lack of understanding of the pathogenesis and mechanisms behind how a cirrhotic liver causes cardiac pathology. This review will focus specifically on insights into the molecular mechanisms that drive this liver-heart interaction. Deeper understanding of the etio-pathogenesis of cirrhotic cardiomyopathy will allow us to design and test treatments that can be targeted to prevent and/or reverse this co-morbid consequence of liver failure and improve health care delivery and outcomes in patients with cirrhosis.
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Affiliation(s)
- Moreshwar S Desai
- Department of Pediatrics, Section of Pediatric Critical Care Medicine and Liver ICU. Baylor College of Medicine, Houston, TX, 77030, USA.
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16
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Wasyluk W, Nowicka-Stążka P, Zwolak A. Heart Metabolism in Sepsis-Induced Cardiomyopathy-Unusual Metabolic Dysfunction of the Heart. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18147598. [PMID: 34300048 PMCID: PMC8303349 DOI: 10.3390/ijerph18147598] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Revised: 06/26/2021] [Accepted: 07/02/2021] [Indexed: 12/11/2022]
Abstract
Due to the need for continuous work, the heart uses up to 8% of the total energy expenditure. Due to the relatively low adenosine triphosphate (ATP) storage capacity, the heart's work is dependent on its production. This is possible due to the metabolic flexibility of the heart, which allows it to use numerous substrates as a source of energy. Under normal conditions, a healthy heart obtains approximately 95% of its ATP by oxidative phosphorylation in the mitochondria. The primary source of energy is fatty acid oxidation, the rest of the energy comes from the oxidation of pyruvate. A failed heart is characterised by a disturbance in these proportions, with the contribution of individual components as a source of energy depending on the aetiology and stage of heart failure. A unique form of cardiac dysfunction is sepsis-induced cardiomyopathy, characterised by a significant reduction in energy production and impairment of cardiac oxidation of both fatty acids and glucose. Metabolic disorders appear to contribute to the pathogenesis of cardiac dysfunction and therefore are a promising target for future therapies. However, as many aspects of the metabolism of the failing heart remain unexplained, this issue requires further research.
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Affiliation(s)
- Weronika Wasyluk
- Chair of Internal Medicine and Department of Internal Medicine in Nursing, Faculty of Health Sciences, Medical University of Lublin, 20-093 Lublin, Poland; (P.N.-S.); (A.Z.)
- Doctoral School, Medical University of Lublin, 20-093 Lublin, Poland
- Correspondence:
| | - Patrycja Nowicka-Stążka
- Chair of Internal Medicine and Department of Internal Medicine in Nursing, Faculty of Health Sciences, Medical University of Lublin, 20-093 Lublin, Poland; (P.N.-S.); (A.Z.)
| | - Agnieszka Zwolak
- Chair of Internal Medicine and Department of Internal Medicine in Nursing, Faculty of Health Sciences, Medical University of Lublin, 20-093 Lublin, Poland; (P.N.-S.); (A.Z.)
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17
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Pakzad KK, Tan JJ, Anderson S, Board M, Clarke K, Carr CA. Metabolic maturation of differentiating cardiosphere-derived cells. Stem Cell Res 2021; 54:102422. [PMID: 34118565 PMCID: PMC8271094 DOI: 10.1016/j.scr.2021.102422] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 05/31/2021] [Accepted: 06/02/2021] [Indexed: 12/13/2022] Open
Abstract
Collagen IV promotes proliferation of cardiosphere-derived cells. Fibronectin supports differentiation of cardiosphere-derived cells. Oxidative metabolism increases as cardiac progenitors mature. Stimulating fatty acid oxidation promotes cardiac progenitor cell maturation.
Cardiosphere-derived cells (CDCs) can be expanded in vitro and induced to differentiate along the cardiac lineage. To recapitulate the phenotype of an adult cardiomyocyte, differentiating progenitors need to upregulate mitochondrial glucose and fatty acid oxidation. Here we cultured and differentiated CDCs using protocols aimed to maintain stemness or to promote differentiation, including triggering fatty acid oxidation using an agonist of peroxisome proliferator-activated receptor alpha (PPARα). Metabolic changes were characterised in undifferentiated CDCs and during differentiation towards a cardiac phenotype. CDCs from rat atria were expanded on fibronectin or collagen IV via cardiosphere formation. Differentiation was assessed using flow cytometry and qPCR and substrate metabolism was quantified using radiolabelled substrates. Collagen IV promoted proliferation of CDCs whereas fibronectin primed cells for differentiation towards a cardiac phenotype. In both populations, treatment with 5-Azacytidine induced a switch towards oxidative metabolism, as shown by changes in gene expression, decreased glycolytic flux and increased oxidation of glucose and palmitate. Addition of a PPARα agonist during differentiation increased both glucose and fatty acid oxidation and expression of cardiac genes. We conclude that oxidative metabolism and cell differentiation act in partnership with increases in one driving an increase in the other.
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Affiliation(s)
| | - Jun Jie Tan
- Department of Physiology, Anatomy & Genetics, University of Oxford, UK; Advanced Medical and Dental Institute, Universiti Sains Malaysia, Penang, Malaysia
| | | | - Mary Board
- Department of Physiology, Anatomy & Genetics, University of Oxford, UK
| | - Kieran Clarke
- Department of Physiology, Anatomy & Genetics, University of Oxford, UK
| | - Carolyn A Carr
- Department of Physiology, Anatomy & Genetics, University of Oxford, UK.
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18
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Chung YJ, Swietach P, Curtis MK, Ball V, Robbins PA, Lakhal-Littleton S. Iron-Deficiency Anemia Results in Transcriptional and Metabolic Remodeling in the Heart Toward a Glycolytic Phenotype. Front Cardiovasc Med 2021; 7:616920. [PMID: 33553263 PMCID: PMC7859254 DOI: 10.3389/fcvm.2020.616920] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 12/01/2020] [Indexed: 12/16/2022] Open
Abstract
Iron deficiency is the most prevalent micronutrient disorder globally. When severe, iron deficiency leads to anemia, which can be deleterious to cardiac function. Given the central role of iron and oxygen in cardiac biology, multiple pathways are expected to be altered in iron-deficiency anemia, and identifying these requires an unbiased approach. To investigate these changes, gene expression and metabolism were studied in mice weaned onto an iron-deficient diet for 6 weeks. Whole-exome transcriptomics (RNAseq) identified over 1,500 differentially expressed genes (DEGs), of which 22% were upregulated and 78% were downregulated in the iron-deficient group, relative to control animals on an iron-adjusted diet. The major biological pathways affected were oxidative phosphorylation and pyruvate metabolism, as well as cardiac contraction and responses related to environmental stress. Cardiac metabolism was studied functionally using in vitro and in vivo methodologies. Spectrometric measurement of the activity of the four electron transport chain complexes in total cardiac lysates showed that the activities of Complexes I and IV were reduced in the hearts of iron-deficient animals. Pyruvate metabolism was assessed in vivo using hyperpolarized 13C magnetic resonance spectroscopy (MRS) of hyperpolarized pyruvate. Hearts from iron-deficient and anemic animals showed significantly decreased flux through pyruvate dehydrogenase and increased lactic acid production, consistent with tissue hypoxia and induction of genes coding for glycolytic enzymes and H+-monocarboxylate transport-4. Our results show that iron-deficiency anemia results in a metabolic remodeling toward a glycolytic, lactic acid-producing phenotype, a hallmark of hypoxia.
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Affiliation(s)
- Yu Jin Chung
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
- The Rayne Institute, St Thomas' Hospital, London, United Kingdom
| | - Pawel Swietach
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - M. Kate Curtis
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Vicky Ball
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Peter A. Robbins
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Samira Lakhal-Littleton
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
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19
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Metabonomics Analysis of Myocardial Metabolic Dysfunction in Patients with Cardiac Natriuretic Peptide Resistance. Cardiol Res Pract 2020; 2020:1416945. [PMID: 33376601 PMCID: PMC7744244 DOI: 10.1155/2020/1416945] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/29/2020] [Accepted: 10/31/2020] [Indexed: 12/31/2022] Open
Abstract
Brain natriuretic peptide (BNP) is an important biological marker and regulator of cardiac function. BNP resistance is characterized by high concentrations of less functionally effective BNP and common in heart failure (HF) patients. However, the roles and consequences of BNP resistance remain poorly understood. Investigate the effects of cardiac BNP resistance and identify potential metabolic biomarkers for screening and diagnosis. Thirty patients and thirty healthy subjects were enrolled in this study. Cardiac functions were evaluated by echocardiography. The plasma levels of cyclic guanosine monophosphate (cGMP) and BNP were measured by enzyme-linked immunosorbent assay (ELISA) and the cGMP/BNP ratio is calculated to determine cardiac natriuretic peptide resistance. Liquid chromatograph tandem mass spectrometry (LC-MS) based untargeted metabolomics analysis was applied to screen metabolic changes. The cGMP/BNP ratio was markedly lower in HF patients than controls. The cGMP/BNP ratio and ejection fraction (EF) were strongly correlated (R2 = 0.676, P < 0.05). Importantly, metabolic profiles were substantially different between HF patients and healthy controls. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis demonstrated that the differentially expressed metabolites are involved in signaling pathways that regulate cardiac functions. In HF patients, BNP resistance develops in association with a reduction in heart function and metabolic remodeling. It suggests possible functional roles of BNP resistance in the regulation of cardiac metabolism.
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20
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Li Y, Torp MK, Norheim F, Khanal P, Kimmel AR, Stensløkken KO, Vaage J, Dalen KT. Isolated Plin5-deficient cardiomyocytes store less lipid droplets than normal, but without increased sensitivity to hypoxia. Biochim Biophys Acta Mol Cell Biol Lipids 2020; 1866:158873. [PMID: 33373698 DOI: 10.1016/j.bbalip.2020.158873] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 12/17/2020] [Accepted: 12/22/2020] [Indexed: 01/14/2023]
Abstract
Plin5 is abundantly expressed in the heart where it binds to lipid droplets (LDs) and facilitates physical interaction between LDs and mitochondria. We isolated cardiomyocytes from adult Plin5+/+ and Plin5-/- mice to study the role of Plin5 for fatty acid uptake, LD accumulation, fatty acid oxidation, and tolerance to hypoxia. Cardiomyocytes isolated from Plin5-/- mice cultured with oleic acid stored less LDs than Plin5+/+, but comparable levels to Plin5+/+ cardiomyocytes when adipose triglyceride lipase activity was inhibited. The ability to oxidize fatty acids into CO2 was similar between Plin5+/+ and Plin5-/- cardiomyocytes, but Plin5-/- cardiomyocytes had a transient increase in intracellular fatty acid oxidation intermediates. After pre-incubation with oleic acids, Plin5-/- cardiomyocytes retained a higher content of glycogen and showed improved tolerance to hypoxia compared to Plin5+/+. In isolated, perfused hearts, deletion of Plin5 had no important effect on ventricular pressures or infarct size after ischemia. Old Plin5-/- mice had reduced levels of cardiac triacylglycerides, increased heart weight, and apart from modest elevated expression of mRNAs for beta myosin heavy chain Myh7 and the fatty acid transporter Cd36, other genes involved in fatty acid oxidation, glycogen metabolism and glucose utilization were essentially unchanged by removal of Plin5. Plin5 seems to facilitate cardiac LD storage primarily by repressing adipose triglyceride lipase activity without altering cardiac fatty acid oxidation capacity. Expression of Plin5 and cardiac LD content of isolated cardiomyocytes has little importance for tolerance to acute hypoxia and ischemia, which contrasts the protective role for Plin5 in mouse models during myocardial ischemia.
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Affiliation(s)
- Yuchuan Li
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Norway; Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Norway
| | - May-Kristin Torp
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Norway
| | - Frode Norheim
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Norway
| | - Prabhat Khanal
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Norway; Faculty of Biosciences and Aquaculture (FBA), Nord University, Norway
| | - Alan R Kimmel
- Laboratory of Cellular and Developmental Biology, National Institute of Diabetes and Digestive and Kidney Diseases, The National Institutes of Health, Bethesda, MD 20892, USA
| | - Kåre-Olav Stensløkken
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Norway
| | - Jarle Vaage
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Norway; Institute of Clinical Medicine, University of Oslo, Norway; Department of Emergencies and Critical Care, Oslo University Hospital, Oslo, Norway
| | - Knut Tomas Dalen
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Norway; The Norwegian Transgenic Center, Institute of Basic Medical Sciences, University of Oslo, Norway.
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21
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Djordjevic DB, Koracevic G, Djordjevic AD, Lovic DB. Diabetic Cardiomyopathy: Clinical and Metabolic Approach. Curr Vasc Pharmacol 2020; 19:487-498. [PMID: 33143612 DOI: 10.2174/1570161119999201102213214] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 10/04/2020] [Accepted: 10/05/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND Having in mind that diabetes mellitus (DM) and obesity are some of the greatest health challenges of the modern era, diabetic cardiomyopathy (DCM) is becoming more and more recognized in clinical practice. Main Text: Initially, DM is asymptomatic, but it may progress to diastolic and then systolic left ventricular dysfunction, which results in congestive heart failure. A basic feature of this DM complication is the absence of hemodynamically significant stenosis of the coronary blood vessels. Clinical manifestations are the result of several metabolic disorders that are present during DM progression. The complexity of metabolic processes, along with numerous regulatory mechanisms, has been the subject of research that aims at discovering new diagnostic (e.g. myocardial strain with echocardiography and cardiac magnetic resonance) and treatment options. Adequate glycaemic control is not sufficient to prevent or reduce the progression of DCM. Contemporary hypoglycemic medications, such as sodium-glucose transport protein 2 inhibitors, significantly reduce the frequency of cardiovascular complications in patients with DM. Several studies have shown that, unlike the above-stated medications, thiazolidinediones and dipeptidyl peptidase-4 inhibitors are associated with deterioration of heart failure. CONCLUSION Imaging procedures, especially myocardial strain with echocardiography and cardiac magnetic resonance, are useful to identify the early signs of DCM. Research and studies regarding new treatment options are still "in progress".
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Affiliation(s)
- Dragan B Djordjevic
- Medical Faculty, University of Nis, Bulevar Dr. Zoran Djindjic 8, 18000 Nis, Serbia
| | - Goran Koracevic
- Clinical Center Nis, Bulevar Dr. Zoran Djindjic 48, 18000 Nis, Serbia
| | | | - Dragan B Lovic
- Clinic for Internal Diseases Intermedica, Singidunum University Nis, Jovana Ristica 20/III-2, 1800 Nis, United States
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22
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Abstract
Gene expression is needed for the maintenance of heart function under normal conditions and in response to stress. Each cell type of the heart has a specific program controlling transcription. Different types of stress induce modifications of these programs and, if prolonged, can lead to altered cardiac phenotype and, eventually, to heart failure. The transcriptional status of a gene is regulated by the epigenome, a complex network of DNA and histone modifications. Until a few years ago, our understanding of the role of the epigenome in heart disease was limited to that played by histone deacetylation. But over the last decade, the consequences for the maintenance of homeostasis in the heart and for the development of cardiac hypertrophy of a number of other modifications, including DNA methylation and hydroxymethylation, histone methylation and acetylation, and changes in chromatin architecture, have become better understood. Indeed, it is now clear that many levels of regulation contribute to defining the epigenetic landscape required for correct cardiomyocyte function, and that their perturbation is responsible for cardiac hypertrophy and fibrosis. Here, we review these aspects and draw a picture of what epigenetic modification may imply at the therapeutic level for heart failure.
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Affiliation(s)
- Roberto Papait
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy; Humanitas Clinical Research Center-IRCCS, Rozzano, Italy; Humanitas University, Department of Biomedical Sciences, Pieve Emanuele, Italy; and National Research Council of Italy, Institute of Genetics and Biomedical Research, Milan Unit, Rozzano, Italy
| | - Simone Serio
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy; Humanitas Clinical Research Center-IRCCS, Rozzano, Italy; Humanitas University, Department of Biomedical Sciences, Pieve Emanuele, Italy; and National Research Council of Italy, Institute of Genetics and Biomedical Research, Milan Unit, Rozzano, Italy
| | - Gianluigi Condorelli
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy; Humanitas Clinical Research Center-IRCCS, Rozzano, Italy; Humanitas University, Department of Biomedical Sciences, Pieve Emanuele, Italy; and National Research Council of Italy, Institute of Genetics and Biomedical Research, Milan Unit, Rozzano, Italy
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Athithan L, Gulsin GS, McCann GP, Levelt E. Diabetic cardiomyopathy: Pathophysiology, theories and evidence to date. World J Diabetes 2019; 10:490-510. [PMID: 31641426 PMCID: PMC6801309 DOI: 10.4239/wjd.v10.i10.490] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 09/25/2019] [Accepted: 09/25/2019] [Indexed: 02/05/2023] Open
Abstract
The prevalence of type 2 diabetes (T2D) has increased worldwide and doubled over the last two decades. It features among the top 10 causes of mortality and morbidity in the world. Cardiovascular disease is the leading cause of complications in diabetes and within this, heart failure has been shown to be the leading cause of emergency admissions in the United Kingdom. There are many hypotheses and well-evidenced mechanisms by which diabetic cardiomyopathy as an entity develops. This review aims to give an overview of these mechanisms, with particular emphasis on metabolic inflexibility. T2D is associated with inefficient substrate utilisation, an inability to increase glucose metabolism and dependence on fatty acid oxidation within the diabetic heart resulting in mitochondrial uncoupling, glucotoxicity, lipotoxicity and initially subclinical cardiac dysfunction and finally in overt heart failure. The review also gives a concise update on developments within clinical imaging, specifically cardiac magnetic resonance studies to characterise and phenotype early cardiac dysfunction in T2D. A better understanding of the pathophysiology involved provides a platform for targeted therapy in diabetes to prevent the development of early heart failure with preserved ejection fraction.
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Affiliation(s)
- Lavanya Athithan
- Department of Cardiovascular Sciences, University of Leicester and NIHR Leicester Cardiovascular Biomedical Research Centre, Glenfield Hospital, Leicester LE3 9QP, United Kingdom
| | - Gaurav S Gulsin
- Department of Cardiovascular Sciences, University of Leicester and NIHR Leicester Cardiovascular Biomedical Research Centre, Glenfield Hospital, Leicester LE3 9QP, United Kingdom
| | - Gerald P McCann
- Department of Cardiovascular Sciences, University of Leicester and NIHR Leicester Cardiovascular Biomedical Research Centre, Glenfield Hospital, Leicester LE3 9QP, United Kingdom
| | - Eylem Levelt
- Multidisciplinary Cardiovascular Research Centre and Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds LF9 7TF, United Kingdom
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24
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Pepin ME, Drakos S, Ha CM, Tristani-Firouzi M, Selzman CH, Fang JC, Wende AR, Wever-Pinzon O. DNA methylation reprograms cardiac metabolic gene expression in end-stage human heart failure. Am J Physiol Heart Circ Physiol 2019; 317:H674-H684. [PMID: 31298559 PMCID: PMC6843013 DOI: 10.1152/ajpheart.00016.2019] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 05/15/2019] [Accepted: 06/13/2019] [Indexed: 12/24/2022]
Abstract
Heart failure (HF) is a leading cause of morbidity and mortality in the United States and worldwide. As a multifactorial syndrome with unpredictable clinical outcomes, identifying the common molecular underpinnings that drive HF pathogenesis remains a major focus of investigation. Disruption of cardiac gene expression has been shown to mediate a common final cascade of pathological hallmarks wherein the heart reactivates numerous developmental pathways. Although the central regulatory mechanisms that drive this cardiac transcriptional reprogramming remain unknown, epigenetic contributions are likely. In the current study, we examined whether the epigenome, specifically DNA methylation, is reprogrammed in HF to potentiate a pathological shift in cardiac gene expression. To accomplish this, we used paired-end whole genome bisulfite sequencing and next-generation RNA sequencing of left ventricle tissue obtained from seven patients with end-stage HF and three nonfailing donor hearts. We found that differential methylation was localized to promoter-associated cytosine-phosphate-guanine islands, which are established regulatory regions of downstream genes. Hypermethylated promoters were associated with genes involved in oxidative metabolism, whereas promoter hypomethylation enriched glycolytic pathways. Overexpression of plasmid-derived DNA methyltransferase 3A in vitro was sufficient to lower the expression of numerous oxidative metabolic genes in H9c2 rat cardiomyoblasts, further supporting the importance of epigenetic factors in the regulation of cardiac metabolism. Last, we identified binding-site competition via hypermethylation of the nuclear respiratory factor 1 (NRF1) motif, an established upstream regulator of mitochondrial biogenesis. These preliminary observations are the first to uncover an etiology-independent shift in cardiac DNA methylation that corresponds with altered metabolic gene expression in HF.NEW & NOTEWORTHY The failing heart undergoes profound metabolic changes because of alterations in cardiac gene expression, reactivating glycolytic genes and suppressing oxidative metabolic genes. In the current study, we discover that alterations to cardiac DNA methylation encode this fetal-like metabolic gene reprogramming. We also identify novel epigenetic interference of nuclear respiratory factor 1 via hypermethylation of its downstream promoter targets, further supporting a novel contribution of DNA methylation in the metabolic remodeling of heart failure.
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Affiliation(s)
- Mark E Pepin
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama
- Department of Biomedical Engineering, University of Alabama at Birmingham, Birmingham, Alabama
| | - Stavros Drakos
- Nora Eccles Harrison Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, Utah
- Division of Cardiovascular Medicine, Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Chae-Myeong Ha
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Martin Tristani-Firouzi
- Nora Eccles Harrison Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, Utah
| | - Craig H Selzman
- Division of Cardiothoracic Surgery, Department of Surgery, University of Utah, Salt Lake City, Utah
| | - James C Fang
- Division of Cardiovascular Medicine, Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Adam R Wende
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama
- Department of Biomedical Engineering, University of Alabama at Birmingham, Birmingham, Alabama
| | - Omar Wever-Pinzon
- Nora Eccles Harrison Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, Utah
- Division of Cardiovascular Medicine, Department of Internal Medicine, University of Utah, Salt Lake City, Utah
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25
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Jyoti S, Tandon S. Disruption of mitochondrial membrane potential coupled with alterations in cardiac biomarker expression as early cardiotoxic signatures in human ES cell-derived cardiac cells. Hum Exp Toxicol 2019; 38:1111-1124. [PMID: 31179749 DOI: 10.1177/0960327119855132] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Cardiotoxicity is one of the most significant reasons of attrition in drug development. The present study assessed the sensitivity of various endpoints for early monitoring of drug-induced cardiotoxicity using human embryonic stem cell-derived cardiac cells, including precursors as well as mature cardiomyocytes, by correlating changes in cardiac biomarker expression. Directed differentiation was induced and cardiac progenitor cell (CPC) population were treated with cardiotoxic drugs, namely, doxorubicin (Dox) and paclitaxel (Pac), and with noncardiotoxic drug, namely penicillin G. To assess cardiac-specific toxicity, the changes in the expression of key markers of cardiac lineage, such as Nkx2.5, Tbx5, α-myosin heavy chain α-MHC, and cardiac troponin T, were studied using quantitative real-time polymerase chain reaction (qRT-PCR) and flow cytometry (FC). The half-maximal inhibition in the expression of these cardiac markers was analyzed from the dose-response curves. We also assessed the half-maximal inhibition (IC50) in cardiac cells using propidium iodide dye (IC50 PI) and by measuring disruption in the mitochondrial membrane potential (IC50 MMP). We observed that the most sensitive marker was α-MHC in the case of both Dox and Pac, and the order of sensitivity of the various prediction assays was MMP > protein expression by FC > gene expression by qRT-PCR > cell viability by PI staining. The results could enrich the screening of drug-induced cardiotoxicity in vitro and propose disruption in MMP along with downregulation of α-MHC protein as a potential biomarker of predicting cardiotoxicity earlier during drug safety evaluation.
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Affiliation(s)
- Saras Jyoti
- Amity Institute of Molecular Medicine and Stem Cell Research (AIMMSCR), Amity University, Noida, Uttar Pradesh, India
| | - Simran Tandon
- Amity Institute of Molecular Medicine and Stem Cell Research (AIMMSCR), Amity University, Noida, Uttar Pradesh, India
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26
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Sayed A, Valente M, Sassoon D. Does cardiac development provide heart research with novel therapeutic approaches? F1000Res 2018; 7. [PMID: 30450195 PMCID: PMC6221076 DOI: 10.12688/f1000research.15609.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/24/2018] [Indexed: 01/04/2023] Open
Abstract
Embryonic heart progenitors arise at specific spatiotemporal periods that contribute to the formation of distinct cardiac structures. In mammals, the embryonic and fetal heart is hypoxic by comparison to the adult heart. In parallel, the cellular metabolism of the cardiac tissue, including progenitors, undergoes a glycolytic to oxidative switch that contributes to cardiac maturation. While oxidative metabolism is energy efficient, the glycolytic-hypoxic state may serve to maintain cardiac progenitor potential. Consistent with this proposal, the adult epicardium has been shown to contain a reservoir of quiescent cardiac progenitors that are activated in response to heart injury and are hypoxic by comparison to adjacent cardiac tissues. In this review, we discuss the development and potential of the adult epicardium and how this knowledge may provide future therapeutic approaches for cardiac repair.
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Affiliation(s)
- Angeliqua Sayed
- Cellular, Molecular, and Physiological Mechanisms of Heart Failure, Paris-Cardiovascular Research Center (PARCC), European Georges Pompidou Hospital (HEGP), INSERM U970, F-75737 Paris Cedex 15, Paris, France
| | - Mariana Valente
- Cellular, Molecular, and Physiological Mechanisms of Heart Failure, Paris-Cardiovascular Research Center (PARCC), European Georges Pompidou Hospital (HEGP), INSERM U970, F-75737 Paris Cedex 15, Paris, France
| | - David Sassoon
- Cellular, Molecular, and Physiological Mechanisms of Heart Failure, Paris-Cardiovascular Research Center (PARCC), European Georges Pompidou Hospital (HEGP), INSERM U970, F-75737 Paris Cedex 15, Paris, France
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27
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Mani K, Javaheri A, Diwan A. Lysosomes Mediate Benefits of Intermittent Fasting in Cardiometabolic Disease: The Janitor Is the Undercover Boss. Compr Physiol 2018; 8:1639-1667. [PMID: 30215867 DOI: 10.1002/cphy.c180005] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Adaptive responses that counter starvation have evolved over millennia to permit organismal survival, including changes at the level of individual organelles, cells, tissues, and organ systems. In the past century, a shift has occurred away from disease caused by insufficient nutrient supply toward overnutrition, leading to obesity and diabetes, atherosclerosis, and cardiometabolic disease. The burden of these diseases has spurred interest in fasting strategies that harness physiological responses to starvation, thus limiting tissue injury during metabolic stress. Insights gained from animal and human studies suggest that intermittent fasting and chronic caloric restriction extend lifespan, decrease risk factors for cardiometabolic and inflammatory disease, limit tissue injury during myocardial stress, and activate a cardioprotective metabolic program. Acute fasting activates autophagy, an intricately orchestrated lysosomal degradative process that sequesters cellular constituents for degradation, and is critical for cardiac homeostasis during fasting. Lysosomes are dynamic cellular organelles that function as incinerators to permit autophagy, as well as degradation of extracellular material internalized by endocytosis, macropinocytosis, and phagocytosis. The last decade has witnessed an explosion of knowledge that has shaped our understanding of lysosomes as central regulators of cellular metabolism and the fasting response. Intriguingly, lysosomes also store nutrients for release during starvation; and function as a nutrient sensing organelle to couple activation of mammalian target of rapamycin to nutrient availability. This article reviews the evidence for how the lysosome, in the guise of a janitor, may be the "undercover boss" directing cellular processes for beneficial effects of intermittent fasting and restoring homeostasis during feast and famine. © 2018 American Physiological Society. Compr Physiol 8:1639-1667, 2018.
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Affiliation(s)
- Kartik Mani
- John Cochran VA Medical Center, St. Louis, Missouri, USA.,Center for Cardiovascular Research and Division of Cardiology in Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Ali Javaheri
- Center for Cardiovascular Research and Division of Cardiology in Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Abhinav Diwan
- Center for Cardiovascular Research and Division of Cardiology in Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA.,Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri, USA
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28
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Single allele Lmbrd1 knockout results in cardiac hypertrophy. J Formos Med Assoc 2018; 117:471-479. [DOI: 10.1016/j.jfma.2017.05.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 04/06/2017] [Accepted: 05/02/2017] [Indexed: 12/19/2022] Open
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29
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Huber JS, Hernandez AM, Janabi M, O'Neil JP, Brennan KM, Murphy ST, Seo Y, Gullberg GT. Longitudinal Evaluation of Myocardial Fatty Acid and Glucose Metabolism in Fasted and Nonfasted Spontaneously Hypertensive Rats Using MicroPET/CT. Mol Imaging 2018; 16:1536012117724558. [PMID: 28877656 PMCID: PMC5593226 DOI: 10.1177/1536012117724558] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Using longitudinal micro positron emission tomography (microPET)/computed tomography (CT) studies, we quantified changes in myocardial metabolism and perfusion in spontaneously hypertensive rats (SHRs), a model of left ventricular hypertrophy (LVH). Fatty acid and glucose metabolism were quantified in the hearts of SHRs and Wistar-Kyoto (WKY) normotensive rats using long-chain fatty acid analog 18F-fluoro-6-thia heptadecanoic acid (18F-FTHA) and glucose analog 18F-fluorodeoxyglucose (18F-FDG) under normal or fasting conditions. We also used 18F-fluorodihydrorotenol (18F-FDHROL) to investigate perfusion in their hearts without fasting. Rats were imaged at 4 or 5 times over their life cycle. Compartment modeling was used to estimate the rate constants for the radiotracers. Blood samples were obtained and analyzed for glucose and free fatty acid concentrations. SHRs demonstrated no significant difference in 18F-FDHROL wash-in rate constant (P = .1) and distribution volume (P = .1), significantly higher 18F-FDG myocardial influx rate constant (P = 4×10−8), and significantly lower 18F-FTHA myocardial influx rate constant (P = .007) than WKYs during the 2009-2010 study without fasting. SHRs demonstrated a significantly higher 18F-FDHROL wash-in rate constant (P = 5×10−6) and distribution volume (P = 3×10−8), significantly higher 18F-FDG myocardial influx rate constant (P = 3×10−8), and a higher trend of 18F-FTHA myocardial influx rate constant (not significant, P = .1) than WKYs during the 2011–2012 study with fasting. Changes in glucose plasma concentrations were generally negatively correlated with corresponding radiotracer influx rate constant changes. The study indicates a switch from preferred fatty acid metabolism to increased glucose metabolism with hypertrophy. Increased perfusion during the 2011-2012 study may be indicative of increased aerobic metabolism in the SHR model of LVH.
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Affiliation(s)
- Jennifer S Huber
- 1 Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Andrew M Hernandez
- 2 Department of Radiology, University of California Davis, Sacramento, CA, USA
| | - Mustafa Janabi
- 1 Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - James P O'Neil
- 1 Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Kathleen M Brennan
- 1 Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Stephanie T Murphy
- 3 Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA
| | - Youngho Seo
- 1 Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.,3 Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA.,4 Department of Radiation Oncology, University of California, San Francisco, CA, USA.,5 UC Berkeley-UCSF Graduate Program in Bioengineering, Berkeley and San Francisco, CA, USA
| | - Grant T Gullberg
- 1 Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.,3 Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA.,5 UC Berkeley-UCSF Graduate Program in Bioengineering, Berkeley and San Francisco, CA, USA
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30
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Wang K, Xu Y, Sun Q, Long J, Liu J, Ding J. Mitochondria regulate cardiac contraction through ATP-dependent and independent mechanisms. Free Radic Res 2018; 52:1256-1265. [PMID: 29544373 DOI: 10.1080/10715762.2018.1453137] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The multipurpose organelle mitochondria play an essential role(s) in controlling cardiac muscle contraction. Mitochondria, not only function as the powerhouses and the energy source of myocytes but also modulate intracellular Ca2+ homeostasis, the production of intermediary metabolites/reactive oxygen species (ROS), and other cellular processes. Those molecular events can substantially influence myocardial contraction. Mitochondrial dysfunction is usually associated with cardiac remodelling, and is the causal factor of heart contraction defects in many cases. The manipulation of mitochondria or mitochondria-relevant pathways appears to be a promising therapeutic approach to treat the diseases.
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Affiliation(s)
- Kexin Wang
- a Center for Mitochondrial Biology and Medicine, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology & Frontier Institute of Science and Technology, Xi'an Jiaotong University , Xi'an , China
| | - Yang Xu
- a Center for Mitochondrial Biology and Medicine, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology & Frontier Institute of Science and Technology, Xi'an Jiaotong University , Xi'an , China
| | - Qiong Sun
- a Center for Mitochondrial Biology and Medicine, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology & Frontier Institute of Science and Technology, Xi'an Jiaotong University , Xi'an , China
| | - Jiangang Long
- a Center for Mitochondrial Biology and Medicine, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology & Frontier Institute of Science and Technology, Xi'an Jiaotong University , Xi'an , China
| | - Jiankang Liu
- a Center for Mitochondrial Biology and Medicine, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology & Frontier Institute of Science and Technology, Xi'an Jiaotong University , Xi'an , China
| | - Jian Ding
- a Center for Mitochondrial Biology and Medicine, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology & Frontier Institute of Science and Technology, Xi'an Jiaotong University , Xi'an , China
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31
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Rysä J, Tokola H, Ruskoaho H. Mechanical stretch induced transcriptomic profiles in cardiac myocytes. Sci Rep 2018; 8:4733. [PMID: 29549296 PMCID: PMC5856749 DOI: 10.1038/s41598-018-23042-w] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 03/06/2018] [Indexed: 12/15/2022] Open
Abstract
Mechanical forces are able to activate hypertrophic growth of cardiomyocytes in the overloaded myocardium. However, the transcriptional profiles triggered by mechanical stretch in cardiac myocytes are not fully understood. Here, we performed the first genome-wide time series study of gene expression changes in stretched cultured neonatal rat ventricular myocytes (NRVM)s, resulting in 205, 579, 737, 621, and 1542 differentially expressed (>2-fold, P < 0.05) genes in response to 1, 4, 12, 24, and 48 hours of cyclic mechanical stretch. We used Ingenuity Pathway Analysis to predict functional pathways and upstream regulators of differentially expressed genes in order to identify regulatory networks that may lead to mechanical stretch induced hypertrophic growth of cardiomyocytes. We also performed micro (miRNA) expression profiling of stretched NRVMs, and identified that a total of 8 and 87 miRNAs were significantly (P < 0.05) altered by 1-12 and 24-48 hours of mechanical stretch, respectively. Finally, through integration of miRNA and mRNA data, we predicted the miRNAs that regulate mRNAs potentially leading to the hypertrophic growth induced by mechanical stretch. These analyses predicted nuclear factor-like 2 (Nrf2) and interferon regulatory transcription factors as well as the let-7 family of miRNAs as playing roles in the regulation of stretch-regulated genes in cardiomyocytes.
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Affiliation(s)
- Jaana Rysä
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland.
- Research Unit of Biomedicine, Pharmacology and Toxicology, University of Oulu, Oulu, Finland.
| | - Heikki Tokola
- Research Unit of Biomedicine, Pharmacology and Toxicology, University of Oulu, Oulu, Finland
- Department of Pathology, Cancer Research and Translational Medicine Research Unit, University of Oulu and Oulu University Hospital, Oulu, Finland
| | - Heikki Ruskoaho
- Research Unit of Biomedicine, Pharmacology and Toxicology, University of Oulu, Oulu, Finland
- Drug Research Program, Division of Pharmacology and Pharmacotherapy, University of Helsinki, Helsinki, Finland
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32
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Molecular mechanisms of cardiac pathology in diabetes - Experimental insights. Biochim Biophys Acta Mol Basis Dis 2017; 1864:1949-1959. [PMID: 29109032 DOI: 10.1016/j.bbadis.2017.10.035] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 10/09/2017] [Accepted: 10/27/2017] [Indexed: 12/11/2022]
Abstract
Diabetic cardiomyopathy is a distinct pathology independent of co-morbidities such as coronary artery disease and hypertension. Diminished glucose uptake due to impaired insulin signaling and decreased expression of glucose transporters is associated with a shift towards increased reliance on fatty acid oxidation and reduced cardiac efficiency in diabetic hearts. The cardiac metabolic profile in diabetes is influenced by disturbances in circulating glucose, insulin and fatty acids, and alterations in cardiomyocyte signaling. In this review, we focus on recent preclinical advances in understanding the molecular mechanisms of diabetic cardiomyopathy. Genetic manipulation of cardiomyocyte insulin signaling intermediates has demonstrated that partial cardiac functional rescue can be achieved by upregulation of the insulin signaling pathway in diabetic hearts. Inconsistent findings have been reported relating to the role of cardiac AMPK and β-adrenergic signaling in diabetes, and systemic administration of agents targeting these pathways appear to elicit some cardiac benefit, but whether these effects are related to direct cardiac actions is uncertain. Overload of cardiomyocyte fuel storage is evident in the diabetic heart, with accumulation of glycogen and lipid droplets. Cardiac metabolic dysregulation in diabetes has been linked with oxidative stress and autophagy disturbance, which may lead to cell death induction, fibrotic 'backfill' and cardiac dysfunction. This review examines the weight of evidence relating to the molecular mechanisms of diabetic cardiomyopathy, with a particular focus on metabolic and signaling pathways. Areas of uncertainty in the field are highlighted and important knowledge gaps for further investigation are identified. This article is part of a Special issue entitled Cardiac adaptations to obesity, diabetes and insulin resistance, edited by Professors Jan F.C. Glatz, Jason R.B. Dyck and Christine Des Rosiers.
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33
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Li T, Xu J, Qin X, Hou Z, Guo Y, Liu Z, Wu J, Zheng H, Zhang X, Gao F. Glucose oxidation positively regulates glucose uptake and improves cardiac function recovery after myocardial reperfusion. Am J Physiol Endocrinol Metab 2017; 313:E577-E585. [PMID: 28325730 DOI: 10.1152/ajpendo.00014.2017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 03/10/2017] [Accepted: 03/15/2017] [Indexed: 01/31/2023]
Abstract
Myocardial reperfusion decreases glucose oxidation and uncouples glucose oxidation from glycolysis. Therapies that increase glucose oxidation lessen myocardial ischemia-reperfusion (I/R) injury. However, the regulation of glucose uptake during reperfusion remains poorly understood. We found that glucose uptake was remarkably diminished in the myocardium following reperfusion in Sprague-Dawley rats as detected by 18F-labeled and fluorescent-labeled glucose analogs, even though GLUT1 was upregulated by threefold and GLUT4 translocation remained unchanged compared with those of sham-treated rats. The decreased glucose uptake was accompanied by suppressed glucose oxidation. Interestingly, stimulating glucose oxidation by inhibition of pyruvate dehydrogenase kinase 4 (PDK4), a rate-limiting enzyme for glucose oxidation, increased glucose uptake and alleviated I/R injury. In vitro data in neonatal myocytes showed that PDK4 overexpression decreased glucose uptake, whereas its knockdown increased glucose uptake, suggesting that PDK4 has a role in regulating glucose uptake. Moreover, inhibition of PDK4 increased myocardial glucose uptake with concomitant enhancement of cardiac insulin sensitivity following myocardial I/R. These results showed that the suppressed glucose oxidation mediated by PDK4 contributes to the reduced glucose uptake in the myocardium following reperfusion, and enhancement of glucose uptake exerts cardioprotection. The findings suggest that stimulating glucose oxidation via PDK4 could be an efficient approach to improve recovery from myocardial I/R injury.
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Affiliation(s)
- Tingting Li
- School of Aerospace Medicine, Fourth Military Medical University, Xi'an, China; and
| | - Jie Xu
- School of Aerospace Medicine, Fourth Military Medical University, Xi'an, China; and
| | - Xinghua Qin
- School of Aerospace Medicine, Fourth Military Medical University, Xi'an, China; and
| | - Zuoxu Hou
- School of Aerospace Medicine, Fourth Military Medical University, Xi'an, China; and
| | - Yongzheng Guo
- School of Aerospace Medicine, Fourth Military Medical University, Xi'an, China; and
| | - Zhenhua Liu
- School of Aerospace Medicine, Fourth Military Medical University, Xi'an, China; and
| | - Jianjiang Wu
- Department of Anesthesiology, First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
| | - Hong Zheng
- Department of Anesthesiology, First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
| | - Xing Zhang
- School of Aerospace Medicine, Fourth Military Medical University, Xi'an, China; and
| | - Feng Gao
- School of Aerospace Medicine, Fourth Military Medical University, Xi'an, China; and
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34
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Kadkhodayan A, Lin CH, Coggan AR, Kisrieva-Ware Z, Schechtman KB, Novak E, Joseph SM, Dávila-Román VG, Gropler RJ, Dence C, Peterson LR. Sex affects myocardial blood flow and fatty acid substrate metabolism in humans with nonischemic heart failure. J Nucl Cardiol 2017; 24:1226-1235. [PMID: 27048307 PMCID: PMC5517366 DOI: 10.1007/s12350-016-0467-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2015] [Accepted: 02/25/2016] [Indexed: 01/08/2023]
Abstract
BACKGROUND In animal models of heart failure (HF), myocardial metabolism shifts from high-energy fatty acid (FA) metabolism toward glucose. However, FA (vs glucose) metabolism generates more ATP/mole; thus, FA metabolism may be especially advantageous in HF. Sex modulates myocardial blood flow (MBF) and substrate metabolism in normal humans. Whether sex affects MBF and metabolism in patients with HF is unknown. METHODS AND RESULTS We studied 19 well-matched men and women with nonischemic HF (EF ≤ 35%). MBF and myocardial substrate metabolism were quantified using positron emission tomography. Women had higher MBF (mL/g/minute), FA uptake (mL/g/minute), and FA utilization (nmol/g/minute) (P < 0.005, P < 0.005, P < 0.05, respectively) and trended toward having higher FA oxidation than men (P = 0.09). These findings were independent of age, obesity, and insulin resistance. There were no sex-related differences in fasting myocardial glucose uptake or metabolism. Higher MBF was related to improved event-free survival (HR 0.31, P = 0.02). CONCLUSIONS In nonischemic HF, women have higher MBF and FA uptake and metabolism than men, irrespective of age, obesity, or insulin resistance. Moreover, higher MBF portends a better prognosis. These sex-related differences should be taken into account in the development and targeting of novel agents aimed at modulating MBF and metabolism in HF.
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Affiliation(s)
- Ana Kadkhodayan
- Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
- Cardiovascular Division, Department of Medicine, Mayo Clinic, Rochester, MN, USA
| | - C Huie Lin
- Cardiovascular Division, Department of Medicine, Washington University School of Medicine, Campus Box 8086, 660 S. Euclid Ave, St. Louis, MO, 63110, USA
- Debakey Cardiovascular Associates, Houston Methodist Hospital, Houston, USA
| | - Andrew R Coggan
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Zulfia Kisrieva-Ware
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Kenneth B Schechtman
- Division of Biostatistics, Washington University School of Medicine, St. Louis, MO, USA
| | - Eric Novak
- Cardiovascular Division, Department of Medicine, Washington University School of Medicine, Campus Box 8086, 660 S. Euclid Ave, St. Louis, MO, 63110, USA
| | - Susan M Joseph
- Cardiovascular Division, Department of Medicine, Washington University School of Medicine, Campus Box 8086, 660 S. Euclid Ave, St. Louis, MO, 63110, USA
| | - Víctor G Dávila-Román
- Cardiovascular Division, Department of Medicine, Washington University School of Medicine, Campus Box 8086, 660 S. Euclid Ave, St. Louis, MO, 63110, USA
| | - Robert J Gropler
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Carmen Dence
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Linda R Peterson
- Cardiovascular Division, Department of Medicine, Washington University School of Medicine, Campus Box 8086, 660 S. Euclid Ave, St. Louis, MO, 63110, USA.
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Abstract
The heart utilizes large amounts of fatty acids as energy providing substrates. The physiological balance of lipid uptake and oxidation prevents accumulation of excess lipids. Several processes that affect cardiac function, including ischemia, obesity, diabetes mellitus, sepsis, and most forms of heart failure lead to altered fatty acid oxidation and often also to the accumulation of lipids. There is now mounting evidence associating certain species of these lipids with cardiac lipotoxicity and subsequent myocardial dysfunction. Experimental and clinical data are discussed and paths to reduction of toxic lipids as a means to improve cardiac function are suggested.
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Affiliation(s)
- P Christian Schulze
- From the Divisions of Cardiology, Friedrich-Schiller-University Jena, Germany, and Columbia University, New York, NY (P.C.S.); Metabolic Biology Laboratory, Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA (K.D.); and Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, New York University School of Medicine, New York, NY (I.J.G.).
| | - Konstantinos Drosatos
- From the Divisions of Cardiology, Friedrich-Schiller-University Jena, Germany, and Columbia University, New York, NY (P.C.S.); Metabolic Biology Laboratory, Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA (K.D.); and Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, New York University School of Medicine, New York, NY (I.J.G.)
| | - Ira J Goldberg
- From the Divisions of Cardiology, Friedrich-Schiller-University Jena, Germany, and Columbia University, New York, NY (P.C.S.); Metabolic Biology Laboratory, Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA (K.D.); and Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, New York University School of Medicine, New York, NY (I.J.G.)
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Levelt E, Rodgers CT, Clarke WT, Mahmod M, Ariga R, Francis JM, Liu A, Wijesurendra RS, Dass S, Sabharwal N, Robson MD, Holloway CJ, Rider OJ, Clarke K, Karamitsos TD, Neubauer S. Cardiac energetics, oxygenation, and perfusion during increased workload in patients with type 2 diabetes mellitus. Eur Heart J 2016; 37:3461-3469. [PMID: 26392437 PMCID: PMC5201143 DOI: 10.1093/eurheartj/ehv442] [Citation(s) in RCA: 120] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 07/27/2015] [Accepted: 08/12/2015] [Indexed: 12/12/2022] Open
Abstract
AIMS Patients with type 2 diabetes mellitus (T2DM) are known to have impaired resting myocardial energetics and impaired myocardial perfusion reserve, even in the absence of obstructive epicardial coronary artery disease (CAD). Whether or not the pre-existing energetic deficit is exacerbated by exercise, and whether the impaired myocardial perfusion causes deoxygenation and further energetic derangement during exercise stress, is uncertain. METHODS AND RESULTS Thirty-one T2DM patients, on oral antidiabetic therapies with a mean HBA1c of 7.4 ± 1.3%, and 17 matched controls underwent adenosine stress cardiovascular magnetic resonance for assessment of perfusion [myocardial perfusion reserve index (MPRI)] and oxygenation [blood-oxygen level-dependent (BOLD) signal intensity change (SIΔ)]. Cardiac phosphorus-MR spectroscopy was performed at rest and during leg exercise. Significant CAD (>50% coronary stenosis) was excluded in all patients by coronary computed tomographic angiography. Resting phosphocreatine to ATP (PCr/ATP) was reduced by 17% in patients (1.74 ± 0.26, P = 0.001), compared with controls (2.07 ± 0.35); during exercise, there was a further 12% reduction in PCr/ATP (P = 0.005) in T2DM patients, but no change in controls. Myocardial perfusion and oxygenation were decreased in T2DM (MPRI 1.61 ± 0.43 vs. 2.11 ± 0.68 in controls, P = 0.002; BOLD SIΔ 7.3 ± 7.8 vs. 17.1 ± 7.2% in controls, P < 0.001). Exercise PCr/ATP correlated with MPRI (r = 0.50, P = 0.001) and BOLD SIΔ (r = 0.32, P = 0.025), but there were no correlations between rest PCr/ATP and MPRI or BOLD SIΔ. CONCLUSION The pre-existing energetic deficit in diabetic cardiomyopathy is exacerbated by exercise; stress PCr/ATP correlates with impaired perfusion and oxygenation. Our findings suggest that, in diabetes, coronary microvascular dysfunction exacerbates derangement of cardiac energetics under conditions of increased workload.
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Affiliation(s)
- Eylem Levelt
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford Centre for Clinical Magnetic Resonance Research, University of Oxford, John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, UK
| | - Christopher T Rodgers
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford Centre for Clinical Magnetic Resonance Research, University of Oxford, John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK
| | - William T Clarke
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford Centre for Clinical Magnetic Resonance Research, University of Oxford, John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK
| | - Masliza Mahmod
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford Centre for Clinical Magnetic Resonance Research, University of Oxford, John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK
| | - Rina Ariga
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford Centre for Clinical Magnetic Resonance Research, University of Oxford, John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK
| | - Jane M Francis
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford Centre for Clinical Magnetic Resonance Research, University of Oxford, John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK
| | - Alexander Liu
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford Centre for Clinical Magnetic Resonance Research, University of Oxford, John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK
| | - Rohan S Wijesurendra
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford Centre for Clinical Magnetic Resonance Research, University of Oxford, John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK
| | - Saira Dass
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford Centre for Clinical Magnetic Resonance Research, University of Oxford, John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK
| | | | - Matthew D Robson
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford Centre for Clinical Magnetic Resonance Research, University of Oxford, John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK
| | - Cameron J Holloway
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford Centre for Clinical Magnetic Resonance Research, University of Oxford, John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, UK
- St. Vincent's Hospital, Sydney, Australia
| | - Oliver J Rider
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford Centre for Clinical Magnetic Resonance Research, University of Oxford, John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK
| | - Kieran Clarke
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, UK
| | - Theodoros D Karamitsos
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford Centre for Clinical Magnetic Resonance Research, University of Oxford, John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK
- 1st Department of Cardiology, AHEPA Hospital, Aristotle University, Thessaloniki, Greece
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford Centre for Clinical Magnetic Resonance Research, University of Oxford, John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK
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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: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [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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38
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Nemutlu E, Gupta A, Zhang S, Viqar M, Holmuhamedov E, Terzic A, Jahangir A, Dzeja P. Decline of Phosphotransfer and Substrate Supply Metabolic Circuits Hinders ATP Cycling in Aging Myocardium. PLoS One 2015; 10:e0136556. [PMID: 26378442 PMCID: PMC4574965 DOI: 10.1371/journal.pone.0136556] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 08/04/2015] [Indexed: 12/24/2022] Open
Abstract
Integration of mitochondria with cytosolic ATP-consuming/ATP-sensing and substrate supply processes is critical for muscle bioenergetics and electrical activity. Whether age-dependent muscle weakness and increased electrical instability depends on perturbations in cellular energetic circuits is unknown. To define energetic remodeling of aged atrial myocardium we tracked dynamics of ATP synthesis-utilization, substrate supply, and phosphotransfer circuits through adenylate kinase (AK), creatine kinase (CK), and glycolytic/glycogenolytic pathways using 18O stable isotope-based phosphometabolomic technology. Samples of intact atrial myocardium from adult and aged rats were subjected to 18O-labeling procedure at resting basal state, and analyzed using the 18O-assisted HPLC-GC/MS technique. Characteristics for aging atria were lower inorganic phosphate Pi[18O], γ-ATP[18O], β-ADP[18O], and creatine phosphate CrP[18O] 18O-labeling rates indicating diminished ATP utilization-synthesis and AK and CK phosphotransfer fluxes. Shift in dynamics of glycolytic phosphotransfer was reflected in the diminished G6P[18O] turnover with relatively constant glycogenolytic flux or G1P[18O] 18O-labeling. Labeling of G3P[18O], an indicator of G3P-shuttle activity and substrate supply to mitochondria, was depressed in aged myocardium. Aged atrial myocardium displayed reduced incorporation of 18O into second (18O2), third (18O3), and fourth (18O4) positions of Pi[18O] and a lower Pi[18O]/γ-ATP[18 O]-labeling ratio, indicating delayed energetic communication and ATP cycling between mitochondria and cellular ATPases. Adrenergic stress alleviated diminished CK flux, AK catalyzed β-ATP turnover and energetic communication in aging atria. Thus, 18O-assisted phosphometabolomics uncovered simultaneous phosphotransfer through AK, CK, and glycolytic pathways and G3P substrate shuttle deficits hindering energetic communication and ATP cycling, which may underlie energetic vulnerability of aging atrial myocardium.
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Affiliation(s)
- Emirhan Nemutlu
- Division of Cardiovascular Diseases, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Anu Gupta
- Division of Cardiovascular Diseases, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Song Zhang
- Division of Cardiovascular Diseases, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Maria Viqar
- Division of Cardiovascular Diseases, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Ekhson Holmuhamedov
- Center for Integrative Research on Cardiovascular Aging (CIRCA), Aurora University of Wisconsin Medical Group, Aurora Health Care, Milwaukee, Wisconsin, United States of America
| | - Andre Terzic
- Division of Cardiovascular Diseases, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Arshad Jahangir
- Center for Integrative Research on Cardiovascular Aging (CIRCA), Aurora University of Wisconsin Medical Group, Aurora Health Care, Milwaukee, Wisconsin, United States of America
- * E-mail: (PD); (AJ)
| | - Petras Dzeja
- Division of Cardiovascular Diseases, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
- * E-mail: (PD); (AJ)
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Increased COUP-TFII expression in adult hearts induces mitochondrial dysfunction resulting in heart failure. Nat Commun 2015; 6:8245. [PMID: 26356605 PMCID: PMC4568566 DOI: 10.1038/ncomms9245] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 07/30/2015] [Indexed: 12/26/2022] Open
Abstract
Mitochondrial dysfunction and metabolic remodelling are pivotal in the development of cardiomyopathy. Here, we show that myocardial COUP-TFII overexpression causes heart failure in mice, suggesting a causal effect of elevated COUP-TFII levels on development of dilated cardiomyopathy. COUP-TFII represses genes critical for mitochondrial electron transport chain enzyme activity, oxidative stress detoxification and mitochondrial dynamics, resulting in increased levels of reactive oxygen species and lower rates of oxygen consumption in mitochondria. COUP-TFII also suppresses the metabolic regulator PGC-1 network and decreases the expression of key glucose and lipid utilization genes, leading to a reduction in both glucose and oleate oxidation in the hearts. These data suggest that COUP-TFII affects mitochondrial function, impairs metabolic remodelling and has a key role in dilated cardiomyopathy. Last, COUP-TFII haploinsufficiency attenuates the progression of cardiac dilation and improves survival in a calcineurin transgenic mouse model, indicating that COUP-TFII may serve as a therapeutic target for the treatment of dilated cardiomyopathy. Transcription factor COUP-TFII is elevated in the hearts of non-ischaemic cardiomyopathy patients, but the nature of this correlation is unknown. Here the authors show that forced cardiac expression of COUP-TFII in mice causes dilated cardiomyopathy because of altered mitochondrial function and impaired metabolic remodelling.
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40
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Kiermayer C, Northrup E, Schrewe A, Walch A, de Angelis MH, Schoensiegel F, Zischka H, Prehn C, Adamski J, Bekeredjian R, Ivandic B, Kupatt C, Brielmeier M. Heart-Specific Knockout of the Mitochondrial Thioredoxin Reductase (Txnrd2) Induces Metabolic and Contractile Dysfunction in the Aging Myocardium. J Am Heart Assoc 2015; 4:e002153. [PMID: 26199228 PMCID: PMC4608093 DOI: 10.1161/jaha.115.002153] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 05/19/2015] [Indexed: 01/19/2023]
Abstract
BACKGROUND Ubiquitous deletion of thioredoxin reductase 2 (Txnrd2) in mice is embryonically lethal and associated with abnormal heart development, while constitutive, heart-specific Txnrd2 inactivation leads to dilated cardiomyopathy and perinatal death. The significance of Txnrd2 in aging cardiomyocytes, however, has not yet been examined. METHODS AND RESULTS The tamoxifen-inducible heart-specific αMHC-MerCreMer transgene was used to inactivate loxP-flanked Txnrd2 alleles in adult mice. Hearts and isolated mitochondria from aged knockout mice were morphologically and functionally analyzed. Echocardiography revealed a significant increase in left ventricular end-systolic diameters in knockouts. Fractional shortening and ejection fraction were decreased compared with controls. Ultrastructural analysis of cardiomyocytes of aged mice showed mitochondrial degeneration and accumulation of autophagic bodies. A dysregulated autophagic activity was supported by higher levels of lysosome-associated membrane protein 1 (LAMP1), microtubule-associated protein 1A/1B-light chain 3-I (LC3-I), and p62 in knockout hearts. Isolated Txnrd2-deficient mitochondria used less oxygen and tended to produce more reactive oxygen species. Chronic hypoxia inducible factor 1, α subunit stabilization and altered transcriptional and metabolic signatures indicated that energy metabolism is deregulated. CONCLUSIONS These results imply a novel role of Txnrd2 in sustaining heart function during aging and suggest that Txnrd2 may be a modifier of heart failure.
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MESH Headings
- Age Factors
- Animals
- Autophagy
- Blood Pressure
- Disease Models, Animal
- Energy Metabolism
- Gene Expression Profiling/methods
- Gene Expression Regulation
- Genetic Predisposition to Disease
- Heart Failure/enzymology
- Heart Failure/genetics
- Heart Failure/pathology
- Heart Failure/physiopathology
- Hypoxia-Inducible Factor 1, alpha Subunit/genetics
- Hypoxia-Inducible Factor 1, alpha Subunit/metabolism
- Lysosomal Membrane Proteins/genetics
- Lysosomal Membrane Proteins/metabolism
- Metabolomics/methods
- Mice, Knockout
- Microtubule-Associated Proteins/genetics
- Microtubule-Associated Proteins/metabolism
- Mitochondria, Heart/enzymology
- Mitochondria, Heart/ultrastructure
- Myocardial Contraction
- Myocytes, Cardiac/enzymology
- Myocytes, Cardiac/ultrastructure
- Oxidative Stress
- Phenotype
- RNA, Messenger/metabolism
- Reactive Oxygen Species/metabolism
- Stroke Volume
- Thioredoxin Reductase 2/deficiency
- Thioredoxin Reductase 2/genetics
- Time Factors
- Ventricular Dysfunction, Left/enzymology
- Ventricular Dysfunction, Left/genetics
- Ventricular Dysfunction, Left/physiopathology
- Ventricular Function, Left
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Affiliation(s)
- Claudia Kiermayer
- Research Unit Comparative Medicine, Helmholtz Zentrum München, German Research Center for Environmental HealthNeuherberg, Germany
| | - Emily Northrup
- Research Unit Comparative Medicine, Helmholtz Zentrum München, German Research Center for Environmental HealthNeuherberg, Germany
| | - Anja Schrewe
- Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental HealthNeuherberg, Germany
| | - Axel Walch
- Reserach Unit Analytical Pathology, Helmholtz Zentrum München, German Research Center for Environmental HealthNeuherberg, Germany
| | - Martin Hrabe de Angelis
- Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental HealthNeuherberg, Germany
- Chair of Experimental Genetics, Technische Universität MünchenMunich, Germany
| | - Frank Schoensiegel
- Department of Internal Medicine III, University of HeidelbergHeidelberg, Germany
| | - Hans Zischka
- Institute of molecular Toxicology and Pharmacology, Helmholtz Zentrum München, German Research Center for Environmental HealthNeuherberg, Germany
| | - Cornelia Prehn
- Institute of Experimental Genetics, Genome Analysis Center, Helmholtz Zentrum München, German Research Center for Environmental HealthNeuherberg, Germany
| | - Jerzy Adamski
- Institute of Experimental Genetics, Genome Analysis Center, Helmholtz Zentrum München, German Research Center for Environmental HealthNeuherberg, Germany
- Chair of Experimental Genetics, Technische Universität MünchenMunich, Germany
| | - Raffi Bekeredjian
- Department of Internal Medicine III, University of HeidelbergHeidelberg, Germany
| | - Boris Ivandic
- Department of Internal Medicine III, University of HeidelbergHeidelberg, Germany
| | - Christian Kupatt
- I. Medizinische Klinik und Poliklinik, Klinikum Rechts der Isar, TU MunichMunich, Germany
- German Center for Cardiovascular Research (DZHK) partner site Munich Heart AllianceMunich, Germany
| | - Markus Brielmeier
- Research Unit Comparative Medicine, Helmholtz Zentrum München, German Research Center for Environmental HealthNeuherberg, Germany
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Dong J, Zhao J, Zhang M, Liu G, Wang X, Liu Y, Yang N, Liu Y, Zhao G, Sun J, Tian J, Cheng C, Wei L, Li Y, Li W. β3-Adrenoceptor Impairs Mitochondrial Biogenesis and Energy Metabolism During Rapid Atrial Pacing-Induced Atrial Fibrillation. J Cardiovasc Pharmacol Ther 2015; 21:114-26. [PMID: 26130614 DOI: 10.1177/1074248415590440] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Accepted: 05/11/2015] [Indexed: 11/17/2022]
Abstract
BACKGROUND The β3-adrenoceptor (β3-AR) is implicated in cardiac remodeling. Since metabolic dysfunction due to loss of mitochondria plays an important role in heart diseases, we examined the effects of β3-AR on mitochondrial biogenesis and energy metabolism in atrial fibrillation (AF). METHODS Atrial fibrillation was created by rapid atrial pacing in adult rabbits. Rabbits were randomly divided into 4 groups: control, pacing (P7), β3-AR antagonist (L748337), and β3-AR agonist (BRL37344) groups. Atrial effective refractory period (AERP) and AF induction rate were measured. Atrial concentrations of adenine nucleotides and phosphocreatine were quantified through high-performance liquid chromatography. Mitochondrial DNA content was determined. Real-time polymerase chain reaction and Western blot were used to examine the expression levels of signaling intermediates related to mitochondrial biogenesis. RESULTS After pacing for 7 days, β3-AR was significantly upregulated, AERP was reduced, and the AF induction rate was increased. The total adenine nucleotides pool was significantly reduced due to the decrease in adenosine triphosphate (ATP). The P7 group showed decreased activity of F0F1-ATPase. Mitochondrial DNA content was decreased and mitochondrial respiratory chain subunits were downregulated after pacing. Furthermore, expression of transcription factors involved in mitochondrial biogenesis, including peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), nuclear respiratory factor 1 (NRF-1), and mitochondrial transcription factor A (Tfam), was lower in the P7 group in response to β3-AR activation. Further stimulation of β3-AR with BRL37344 exacerbated these effects, together with a significant decrease in the levels of phosphocreatine. In contrast, inhibition of β3-AR with L748337 partially restored mitochondrial biogenesis and energy metabolism of atria in the paced rabbits. CONCLUSION The activation of β3-AR contributes to atrial metabolic remodeling via transcriptional downregulation of PGC-1α/NRF-1/Tfam pathway that are involved in mitochondrial biogenesis, which ultimately perturbs mitochondrial function in rapid pacing-induced AF. The β3-AR is therefore a potential novel therapeutic target for the treatment or prevention of AF.
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Affiliation(s)
- Jingmei Dong
- Department of Cardiology, First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Jingjing Zhao
- Department of Cardiology, First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Miaomiao Zhang
- Department of Cardiology, First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Guangzhong Liu
- Department of Cardiology, First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Xiaobing Wang
- Department of Cardiology, First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Yixi Liu
- Department of Cardiology, First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Ning Yang
- Ultrasonic Cardiogram Room, First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Yongwu Liu
- Centre for Drug Safety Evaluation, Heilongjiang University of Chinese Medicine, Harbin, China
| | - Guanqi Zhao
- Department of Cardiology, First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Jiayu Sun
- Department of Cardiology, First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Jingpu Tian
- Department of Cardiology, First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Cheping Cheng
- Department of Cardiology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA
| | - Lin Wei
- Department of Cardiology, First Hospital of Harbin City, Harbin, China
| | - Yue Li
- Department of Cardiology, First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Weimin Li
- Department of Cardiology, First Affiliated Hospital of Harbin Medical University, Harbin, China
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42
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Coronary Artery Disease: Regulation of Coronary Blood Flow. Coron Artery Dis 2015. [DOI: 10.1007/978-1-4471-2828-1_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Abstract
Heart failure is a leading cause of morbidity and mortality worldwide, currently affecting 5 million Americans. A syndrome defined on clinical terms, heart failure is the end result of events occurring in multiple heart diseases, including hypertension, myocardial infarction, genetic mutations and diabetes, and metabolic dysregulation, is a hallmark feature. Mounting evidence from clinical and preclinical studies suggests strongly that fatty acid uptake and oxidation are adversely affected, especially in end-stage heart failure. Moreover, metabolic flexibility, the heart's ability to move freely among diverse energy substrates, is impaired in heart failure. Indeed, impairment of the heart's ability to adapt to its metabolic milieu and associated metabolic derangement are important contributing factors in the heart failure pathogenesis. Elucidation of molecular mechanisms governing metabolic control in heart failure will provide critical insights into disease initiation and progression, raising the prospect of advances with clinical relevance.
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Abstract
Normal cardiac function requires high and continuous supply with ATP. As mitochondria are the major source of ATP production, it is apparent that mitochondrial function and cardiac function need to be closely related to each other. When subjected to overload, the heart hypertrophies. Initially, the development of hypertrophy is a compensatory mechanism, and contractile function is maintained. However, when the heart is excessively and/or persistently stressed, cardiac function may deteriorate, leading to the onset of heart failure. There is considerable evidence that alterations in mitochondrial function are involved in the decompensation of cardiac hypertrophy. Here, we review metabolic changes occurring at the mitochondrial level during the development of cardiac hypertrophy and the transition to heart failure. We will focus on changes in mitochondrial substrate metabolism, the electron transport chain and the role of oxidative stress. We will demonstrate that, with respect to mitochondrial adaptations, a clear distinction between hypertrophy and heart failure cannot be made because most of the findings present in overt heart failure can already be found in the various stages of hypertrophy.
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Saks V, Schlattner U, Tokarska-Schlattner M, Wallimann T, Bagur R, Zorman S, Pelosse M, Santos PD, Boucher F, Kaambre T, Guzun R. Systems Level Regulation of Cardiac Energy Fluxes Via Metabolic Cycles: Role of Creatine, Phosphotransfer Pathways, and AMPK Signaling. SYSTEMS BIOLOGY OF METABOLIC AND SIGNALING NETWORKS 2014. [DOI: 10.1007/978-3-642-38505-6_11] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Luo C, Wang H, Chen X, Cui Y, Li H, Long J, Mo X, Liu J. Protection of H9c2 rat cardiomyoblasts against oxidative insults by total paeony glucosides from Radix Paeoniae Rubrae. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2013; 21:20-24. [PMID: 24035226 DOI: 10.1016/j.phymed.2013.08.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Revised: 07/02/2013] [Accepted: 08/02/2013] [Indexed: 06/02/2023]
Abstract
Total paeony glucosides (TPG) extracted from the roots of Radix Paeoniae Rubrae, have been approved for the therapy of rheumatoid arthritis by the State Food and Drug Administration. We previously demonstrated the myocardial protective effects of TPG in both isoprenaline-induced myocardial ischemia rat and acute myocardial infarction rat. However, the underlying mechanism of TPG effect in cardiomyocytes remains to be investigated. The aims of this study were to elucidate the effect of TPG on the activities of antioxidant defense targets and the bioenergetic system in rat cardiomyocytes. The changes of viability, antioxidant defense system activities, protein contents, and mitochondrial functions in tert-butyl hydroperoxide challenged H9c2 rat cardiomyoblasts were evaluated. The results suggest that TPG ameliorated cardiomyoblast dysfunction by preserving antioxidant defense and bioenergetic system.
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Affiliation(s)
- Cheng Luo
- Center for Mitochondrial Biology and Medicine, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology and Frontier Institute of Life Science, FIST, Xi'an Jiaotong University, Xi'an 710049, China
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Hernandez AM, Huber JS, Murphy ST, Janabi M, Zeng GL, Brennan KM, O'Neil JP, Seo Y, Gullberg GT. Longitudinal evaluation of left ventricular substrate metabolism, perfusion, and dysfunction in the spontaneously hypertensive rat model of hypertrophy using small-animal PET/CT imaging. J Nucl Med 2013; 54:1938-45. [PMID: 24092939 DOI: 10.2967/jnumed.113.120105] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED Myocardial metabolic and perfusion imaging is a vital tool for understanding the physiologic consequences of heart failure. We used PET imaging to examine the longitudinal kinetics of (18)F-FDG and 14(R,S)-(18)F-fluoro-6-thia-heptadecanoic acid ((18)F-FTHA) as analogs of glucose and fatty acid (FA) to quantify metabolic substrate shifts with the spontaneously hypertensive rat (SHR) as a model of left ventricular hypertrophy (LVH) and failure. Myocardial perfusion and left ventricular function were also investigated using a newly developed radiotracer (18)F-fluorodihydrorotenol ((18)F-FDHROL). METHODS Longitudinal dynamic electrocardiogram-gated small-animal PET/CT studies were performed with 8 SHR and 8 normotensive Wistar-Kyoto (WKY) rats over their life cycle. We determined the myocardial influx rate constant for (18)F-FDG and (18)F-FTHA (Ki(FDG) and Ki(FTHA), respectively) and the wash-in rate constant for (18)F-FDHROL (K1(FDHROL)). (18)F-FDHROL data were also used to quantify left ventricular ejection fraction (LVEF) and end-diastolic volume (EDV). Blood samples were drawn to independently measure plasma concentrations of glucose, insulin, and free fatty acids (FFAs). RESULTS Ki(FDG) and Ki(FTHA) were higher in SHRs than WKY rats (P < 3 × 10(-8) and 0.005, respectively) independent of age. A decrease in Ki(FDG) with age was evident when models were combined (P = 0.034). The SHR exhibited higher K1(FDHROL) (P < 5 × 10(-6)) than the control, with no age-dependent trends in either model (P = 0.058). Glucose plasma concentrations were lower in SHRs than controls (P < 6 × 10(-12)), with an age-dependent rise for WKY rats (P < 2 × 10(-5)). Insulin plasma concentrations were higher in SHRs than controls (P < 3 × 10(-3)), with an age-dependent decrease when models were combined (P = 0.046). FFA levels were similar between models (P = 0.374), but an increase with age was evident only in SHR (P < 7 × 10(-6)). CONCLUSION The SHR exhibited alterations in myocardial substrate use at 8 mo characterized by increased glucose and FA utilizations. At 20 mo, the SHR had LVH characterized by decreased LVEF and increased EDV, while simultaneously sustaining higher glucose and similar FA utilizations (compared with WKY rats), which indicates maladaptation of energy substrates in the failing heart. Elevated K1(FDHROL) in the SHR may reflect elevated oxygen consumption and decreased capillary density in the hypertrophied heart. From our findings, metabolic changes appear to precede mechanical changes of LVH progression in the SHR model.
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Affiliation(s)
- Andrew M Hernandez
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California
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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] [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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Chew MS, Shekar K, Brand BA, Norin C, Barnett AG. Depletion of myocardial glucose is observed during endotoxemic but not hemorrhagic shock in a porcine model. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2013; 17:R164. [PMID: 23886047 PMCID: PMC4231428 DOI: 10.1186/cc12843] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2012] [Accepted: 07/25/2013] [Indexed: 11/22/2022]
Abstract
Introduction Metabolic dysfunction is one of the hallmarks of sepsis yet little is known about local changes in key organs such as the heart. The aim of this study was to compare myocardial metabolic changes by direct measurements of substrates, such as glucose, lactate and pyruvate, using microdialysis (MD) in in-vivo porcine endotoxemic and hemorrhagic shock. To assess whether these changes were specific to the heart, we simultaneously investigated substrate levels in skeletal muscle. Methods Twenty-six female pigs were randomized to three groups: control (C) n = 8, endotoxemic shock (E) n = 9 and hemorrhagic shock (H) n = 9. Interstitial myocardial pyruvate, lactate and glucose were measured using MD. Skeletal muscle MD was also performed in all three groups. Results Marked decreases in myocardial glucose were observed in the E group but not in the H group compared to controls (mean difference (CI) in mmol/L: C versus E -1.5(-2.2 to -0.8), P <0.001; H versus E -1.1(-1.8 to -0.4), P = 0.004; C versus H -0.4(-1.1 to 0.3), P = 0.282). Up to four-fold increases in myocardial pyruvate and three-fold increases in lactate were seen in both shock groups with no differences between the two types of shock. There was no evidence of myocardial anaerobic metabolism, with normal lactate:pyruvate (L:P) ratios seen in all animals regardless of the type of shock. In skeletal muscle, decreases in glucose concentrations were observed in the E group only (mean difference: C versus E -0.8(-1.4 to -0.3), P = 0.007). Although skeletal muscle lactate increased in both shock groups, this was accompanied by increases in pyruvate in the E group only (mean difference: C versus E 121(46 to 195), P = 0.003; H versus E 77(7 to 147), P = 0.032; C versus H 43(-30 to 43), P = 0.229). The L:P ratio was increased in skeletal muscle in response to hemorrhagic, but not endotoxemic, shock. Conclusions Endotoxemia, but not hemorrhage, induces a rapid decrease of myocardial glucose levels. Despite the decrease in glucose, myocardial lactate and pyruvate concentrations were elevated and not different than in hemorrhagic shock. In skeletal muscle, substrate patterns during endotoxemic shock mimicked those seen in myocardium. During hemorrhagic shock the skeletal muscle response was characterized by a lack of increase in pyruvate and higher L:P ratios. Hence, metabolic patterns in the myocardium during endotoxemic shock are different than those seen during hemorrhagic shock. Skeletal muscle and myocardium displayed similar substrate patterns during endotoxemic shock but differed during hemorrhagic shock.
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Branovets J, Sepp M, Kotlyarova S, Jepihhina N, Sokolova N, Aksentijevic D, Lygate CA, Neubauer S, Vendelin M, Birkedal R. Unchanged mitochondrial organization and compartmentation of high-energy phosphates in creatine-deficient GAMT-/- mouse hearts. Am J Physiol Heart Circ Physiol 2013; 305:H506-20. [PMID: 23792673 DOI: 10.1152/ajpheart.00919.2012] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Disruption of the creatine kinase (CK) system in hearts of CK-deficient mice leads to changes in the ultrastructure and regulation of mitochondrial respiration. We expected to see similar changes in creatine-deficient mice, which lack the enzyme guanidinoacetate methyltransferase (GAMT) to produce creatine. The aim of this study was to characterize the changes in cardiomyocyte mitochondrial organization, regulation of respiration, and intracellular compartmentation associated with GAMT deficiency. Three-dimensional mitochondrial organization was assessed by confocal microscopy. On populations of permeabilized cardiomyocytes, we recorded ADP and ATP kinetics of respiration, competition between mitochondria and pyruvate kinase for ADP produced by ATPases, ADP kinetics of endogenous pyruvate kinase, and ATP kinetics of ATPases. These data were analyzed by mathematical models to estimate intracellular compartmentation. Quantitative analysis of morphological and kinetic data as well as derived model fits showed no difference between GAMT-deficient and wild-type mice. We conclude that inactivation of the CK system by GAMT deficiency does not alter mitochondrial organization and intracellular compartmentation in relaxed cardiomyocytes. Thus, our results suggest that the healthy heart is able to preserve cardiac function at a basal level in the absence of CK-facilitated energy transfer without compromising intracellular organization and the regulation of mitochondrial energy homeostasis. This raises questions on the importance of the CK system as a spatial energy buffer in unstressed cardiomyocytes.
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Affiliation(s)
- Jelena Branovets
- Laboratory of Systems Biology, Institute of Cybernetics, Tallinn University of Technology, Tallinn, Estonia; and
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