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Choksey A, Carter RD, Thackray BD, Ball V, Kennedy BWC, Ha LHT, Sharma E, Broxholme J, Castro-Guarda M, Murphy MP, Heather LC, Tyler DJ, Timm KN. AICAR confers prophylactic cardioprotection in doxorubicin-induced heart failure in rats. J Mol Cell Cardiol 2024:S0022-2828(24)00055-5. [PMID: 38643934 DOI: 10.1016/j.yjmcc.2024.04.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 04/12/2024] [Accepted: 04/18/2024] [Indexed: 04/23/2024]
Abstract
Doxorubicin (DOX) is a widely used chemotherapeutic agent that can cause serious cardiotoxic side effects, leading to heart failure (HF). Impaired mitochondrial function is thought to be key factor driving progression into HF. We have previously shown in a rat model of DOX-HF that heart failure with reduced ejection fraction correlates with mitochondrial loss and dysfunction. Adenosine monophosphate-dependent kinase (AMPK) is a cellular energy sensor, regulating mitochondrial biogenesis and energy metabolism, including fatty acid oxidation. We hypothesised that AMPK activation could restore mitochondrial function and therefore be a novel cardioprotective strategy for the prevention of DOX-HF. Consequently, we set out to assess whether 5-aminoimidazole-4-carboxamide 1-β-D-ribofuranoside (AICAR), an activator of AMPK, could prevent cardiac functional decline in this chronic intravenous rat model of DOX-HF. In line with our hypothesis, AICAR improved cardiac systolic function. AICAR furthermore improved cardiac mitochondrial fatty acid oxidation, independent of mitochondrial number, and in the absence of observable AMPK-activation. In addition, we found that AICAR prevented loss of myocardial mass. RNAseq analysis showed that this may be driven by normalisation of pathways associated with ribosome function and protein synthesis, which are impaired in DOX-treated rat hearts. AICAR furthermore prevented dyslipidemia and excessive body-weight loss in DOX-treated rats, which may contribute to preservation of myocardial mass. Though it is unclear whether AICAR exerted its cardioprotective effect through cardiac or extra-cardiac AMPK-activation or via an AMPK-independent effect, these results show promise for the use of AICAR as a cardioprotective agent in DOX-HF to both preserve cardiac function and mass.
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Affiliation(s)
- Anurag Choksey
- Department of Physiology Anatomy and Genetics, University of Oxford, UK
| | - Ryan D Carter
- Department of Physiology Anatomy and Genetics, University of Oxford, UK; Doctoral Training Centre, University of Oxford, Keble Road, Oxford, OX1 3NP, UK
| | | | - Vicky Ball
- Department of Physiology Anatomy and Genetics, University of Oxford, UK
| | - Brett W C Kennedy
- Department of Physiology Anatomy and Genetics, University of Oxford, UK; Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK
| | | | - Eshita Sharma
- Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Dr, Headington, Oxford OX3 7BN, UK
| | - John Broxholme
- Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Dr, Headington, Oxford OX3 7BN, UK
| | | | | | - Lisa C Heather
- Department of Physiology Anatomy and Genetics, University of Oxford, UK
| | - Damian J Tyler
- Department of Physiology Anatomy and Genetics, University of Oxford, UK; Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK
| | - Kerstin N Timm
- Department of Physiology Anatomy and Genetics, University of Oxford, UK; Department of Pharmacology, University of Oxford, UK.
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2
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Grist JT, Bøgh N, Hansen ES, Schneider AM, Healicon R, Ball V, Miller JJJJ, Smart S, Couch Y, Buchan AM, Tyler DJ, Laustsen C. Developing a metabolic clearance rate framework as a translational analysis approach for hyperpolarized 13C magnetic resonance imaging. Sci Rep 2023; 13:1613. [PMID: 36709217 PMCID: PMC9884306 DOI: 10.1038/s41598-023-28643-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 01/23/2023] [Indexed: 01/29/2023] Open
Abstract
Hyperpolarized carbon-13 magnetic resonance imaging is a promising technique for in vivo metabolic interrogation of alterations between health and disease. This study introduces a formalism for quantifying the metabolic information in hyperpolarized imaging. This study investigated a novel perfusion formalism and metabolic clearance rate (MCR) model in pre-clinical stroke and in the healthy human brain. Simulations showed that the proposed model was robust to perturbations in T1, transmit B1, and kPL. A significant difference in ipsilateral vs contralateral pyruvate derived cerebral blood flow (CBF) was detected in rats (140 ± 2 vs 89 ± 6 mL/100 g/min, p < 0.01, respectively) and pigs (139 ± 12 vs 95 ± 5 mL/100 g/min, p = 0.04, respectively), along with an increase in fractional metabolism (26 ± 5 vs 4 ± 2%, p < 0.01, respectively) in the rodent brain. In addition, a significant increase in ipsilateral vs contralateral MCR (0.034 ± 0.007 vs 0.017 ± 0.02/s, p = 0.03, respectively) and a decrease in mean transit time (31 ± 8 vs 60 ± 2 s, p = 0.04, respectively) was observed in the porcine brain. In conclusion, MCR mapping is a simple and robust approach to the post-processing of hyperpolarized magnetic resonance imaging.
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Affiliation(s)
- James T Grist
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, UK
- Division of Cardiovascular Medicine, Oxford Centre for Clinical Magnetic Resonance Research, Oxford, UK
- Department of Radiology, Oxford University Hospitals Trust, Oxford, UK
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
| | - Nikolaj Bøgh
- Department of Clinical Medicine, MR Research Centre, Aarhus University, Aarhus, Denmark
| | - Esben Søvsø Hansen
- Department of Clinical Medicine, MR Research Centre, Aarhus University, Aarhus, Denmark
| | - Anna M Schneider
- Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Richard Healicon
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, UK
| | - Vicky Ball
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, UK
| | - Jack J J J Miller
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, UK
- Division of Cardiovascular Medicine, Oxford Centre for Clinical Magnetic Resonance Research, Oxford, UK
- Department of Clinical Medicine, MR Research Centre, Aarhus University, Aarhus, Denmark
| | - Sean Smart
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Yvonne Couch
- Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | | | - Damian J Tyler
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, UK
- Division of Cardiovascular Medicine, Oxford Centre for Clinical Magnetic Resonance Research, Oxford, UK
| | - Christoffer Laustsen
- Department of Clinical Medicine, MR Research Centre, Aarhus University, Aarhus, Denmark.
- Aarhus University Hospital, MR Center, Palle Juul Jensens Boulevard 99, 8200, Aarhus N, Denmark.
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Wilson AD, Richards MA, Curtis MK, Gunadasa-Rohling M, Monterisi S, Loonat AA, Miller JJ, Ball V, Lewis A, Tyler DJ, Moshnikova A, Andreev OA, Reshetnyak YK, Carr C, Swietach P. Acidic environments trigger intracellular H+-sensing FAK proteins to re-balance sarcolemmal acid-base transporters and auto-regulate cardiomyocyte pH. Cardiovasc Res 2022; 118:2946-2959. [PMID: 34897412 PMCID: PMC9648823 DOI: 10.1093/cvr/cvab364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 12/08/2021] [Indexed: 11/12/2022] Open
Abstract
AIMS In cardiomyocytes, acute disturbances to intracellular pH (pHi) are promptly corrected by a system of finely tuned sarcolemmal acid-base transporters. However, these fluxes become thermodynamically re-balanced in acidic environments, which inadvertently causes their set-point pHi to fall outside the physiological range. It is unclear whether an adaptive mechanism exists to correct this thermodynamic challenge, and return pHi to normal. METHODS AND RESULTS Following left ventricle cryo-damage, a diffuse pattern of low extracellular pH (pHe) was detected by acid-sensing pHLIP. Despite this, pHi measured in the beating heart (13C NMR) was normal. Myocytes had adapted to their acidic environment by reducing Cl-/HCO3- exchange (CBE)-dependent acid-loading and increasing Na+/H+ exchange (NHE1)-dependent acid-extrusion, as measured by fluorescence (cSNARF1). The outcome of this adaptation on pHi is revealed as a cytoplasmic alkalinization when cells are superfused at physiological pHe. Conversely, mice given oral bicarbonate (to improve systemic buffering) had reduced myocardial NHE1 expression, consistent with a needs-dependent expression of pHi-regulatory transporters. The response to sustained acidity could be replicated in vitro using neonatal ventricular myocytes incubated at low pHe for 48 h. The adaptive increase in NHE1 and decrease in CBE activities was linked to Slc9a1 (NHE1) up-regulation and Slc4a2 (AE2) down-regulation. This response was triggered by intracellular H+ ions because it persisted in the absence of CO2/HCO3- and became ablated when acidic incubation media had lower chloride, a solution manoeuvre that reduces the extent of pHi-decrease. Pharmacological inhibition of FAK-family non-receptor kinases, previously characterized as pH-sensors, ablated this pHi autoregulation. In support of a pHi-sensing role, FAK protein Pyk2 (auto)phosphorylation was reduced within minutes of exposure to acidity, ahead of adaptive changes to pHi control. CONCLUSIONS Cardiomyocytes fine-tune the expression of pHi-regulators so that pHi is at least 7.0. This autoregulatory feedback mechanism defines physiological pHi and protects it during pHe vulnerabilities.
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Affiliation(s)
- Abigail D Wilson
- Department of Physiology, Anatomy & Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Mark A Richards
- Department of Physiology, Anatomy & Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - M Kate Curtis
- Department of Physiology, Anatomy & Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Mala Gunadasa-Rohling
- Department of Physiology, Anatomy & Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Stefania Monterisi
- Department of Physiology, Anatomy & Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Aminah A Loonat
- Department of Physiology, Anatomy & Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Jack J Miller
- Department of Physiology, Anatomy & Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
- Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, UK
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Radcliffe Department of Medicine, Level 0, John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK
| | - Vicky Ball
- Department of Physiology, Anatomy & Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Andrew Lewis
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Radcliffe Department of Medicine, Level 0, John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK
| | - Damian J Tyler
- Department of Physiology, Anatomy & Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Radcliffe Department of Medicine, Level 0, John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK
| | - Anna Moshnikova
- Physics Department, University of Rhode Island, 2 Lippitt Rd, Kingston, RI 02881, USA
| | - Oleg A Andreev
- Physics Department, University of Rhode Island, 2 Lippitt Rd, Kingston, RI 02881, USA
| | - Yana K Reshetnyak
- Physics Department, University of Rhode Island, 2 Lippitt Rd, Kingston, RI 02881, USA
| | - Carolyn Carr
- Department of Physiology, Anatomy & Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Pawel Swietach
- Department of Physiology, Anatomy & Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
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Healicon R, Rooney CHE, Ball V, Shinozaki A, Miller JJ, Smart S, Radford‐Smith D, Anthony D, Tyler DJ, Grist JT. Assessing the effect of anesthetic gas mixtures on hyperpolarized 13 C pyruvate metabolism in the rat brain. Magn Reson Med 2022; 88:1324-1332. [PMID: 35468245 PMCID: PMC9325476 DOI: 10.1002/mrm.29274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 03/11/2022] [Accepted: 03/31/2022] [Indexed: 11/09/2022]
Abstract
PURPOSE To determine the effect of altering anesthetic oxygen protocols on measurements of cerebral perfusion and metabolism in the rodent brain. METHODS Seven rats were anesthetized and underwent serial MRI scans with hyperpolarized [1-13 C]pyruvate and perfusion weighted imaging. The anesthetic carrier gas protocol used varied from 100:0% to 90:10% to 60:40% O2 :N2 O. Spectra were quantified with AMARES and perfusion imaging was processed using model-free deconvolution. A 1-way ANOVA was used to compare results across groups, with pairwise t tests performed with correction for multiple comparisons. Spearman's correlation analysis was performed between O2 % and MR measurements. RESULTS There was a significant increase in bicarbonate:total 13 C carbon and bicarbonate:13 C pyruvate when moving between 100:0 to 90:10 and 100:0 to 60:40 O2 :N2 O % (0.02 ± 0.01 vs. 0.019 ± 0.005 and 0.02 ± 0.01 vs. 0.05 ± 0.02, respectively) and (0.04 ± 0.01 vs. 0.03 ± 0.01 and 0.04 ± 0.01 vs. 0.08 ± 0.02, respectively). There was a significant difference in 13 C pyruvate time to peak when moving between 100:0 to 90:10 and 100:0 to 60:40 O2 :N2 O % (13 ± 2 vs. 10 ± 1 and 13 ± 2 vs. 7.5 ± 0.5 s, respectively) as well as significant differences in cerebral blood flow (CBF) between gas protocols. Significant correlations between bicarbonate:13 C pyruvate and gas protocol (ρ = -0.47), mean transit time and gas protocol (ρ = 0.41) and 13 C pyruvate time-to-peak and cerebral blood flow (ρ = -0.54) were also observed. CONCLUSIONS These results demonstrate that the detection and quantification of cerebral metabolism and perfusion is dependent on the oxygen protocol used in the anesthetized rodent brain.
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Affiliation(s)
- Richard Healicon
- Department of Physiology, Anatomy, and GeneticsUniversity of OxfordOxfordUnited Kingdom
| | - Catriona H. E. Rooney
- Department of Physiology, Anatomy, and GeneticsUniversity of OxfordOxfordUnited Kingdom
| | - Vicky Ball
- Department of Physiology, Anatomy, and GeneticsUniversity of OxfordOxfordUnited Kingdom
| | - Ayaka Shinozaki
- Department of Physiology, Anatomy, and GeneticsUniversity of OxfordOxfordUnited Kingdom
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of MedicineUniversity of OxfordOxfordUnited Kingdom
| | - Jack J. Miller
- Department of Physiology, Anatomy, and GeneticsUniversity of OxfordOxfordUnited Kingdom
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of MedicineUniversity of OxfordOxfordUnited Kingdom
- Clarendon Laboratory, Department of PhysicsUniversity of OxfordOxfordUnited Kingdom
- The PET Centre and The MR Centre, Clinical MedicineAarhus University and Aarhus University HospitalAarhusDenmark
| | - Sean Smart
- Nuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUnited Kingdom
| | | | - Daniel Anthony
- Department of PharmacologyUniversity of OxfordOxfordUnited Kingdom
| | - Damian J. Tyler
- Department of Physiology, Anatomy, and GeneticsUniversity of OxfordOxfordUnited Kingdom
- The PET Centre and The MR Centre, Clinical MedicineAarhus University and Aarhus University HospitalAarhusDenmark
| | - James T. Grist
- Department of Physiology, Anatomy, and GeneticsUniversity of OxfordOxfordUnited Kingdom
- The PET Centre and The MR Centre, Clinical MedicineAarhus University and Aarhus University HospitalAarhusDenmark
- Department of RadiologyOxford University HospitalsOxfordUnited Kingdom
- Institute of Cancer and Genomic SciencesUniversity of BirminghamBirminghamUnited Kingdom
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5
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Savic D, Ball V, Holzner L, Hauton D, Timm KN, Curtis MK, Heather LC, Tyler DJ. Hyperpolarized magnetic resonance shows that the anti-ischemic drug meldonium leads to increased flux through pyruvate dehydrogenase in vivo resulting in improved post-ischemic function in the diabetic heart. NMR Biomed 2021; 34:e4471. [PMID: 33458907 PMCID: PMC8609426 DOI: 10.1002/nbm.4471] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 11/20/2020] [Accepted: 12/20/2020] [Indexed: 05/07/2023]
Abstract
The diabetic heart has a decreased ability to metabolize glucose. The anti-ischemic drug meldonium may provide a route to counteract this by reducing l-carnitine levels, resulting in improved cardiac glucose utilization. Therefore, the aim of this study was to use the novel technique of hyperpolarized magnetic resonance to investigate the in vivo effects of treatment with meldonium on cardiac metabolism and function in control and diabetic rats. Thirty-six male Wistar rats were injected either with vehicle, or with streptozotocin (55 mg/kg) to induce a model of type 1 diabetes. Daily treatment with either saline or meldonium (100 mg/kg/day) was undertaken for three weeks. in vivo cardiac function and metabolism were assessed with CINE MRI and hyperpolarized magnetic resonance respectively. Isolated perfused hearts were challenged with low-flow ischemia/reperfusion to assess the impact of meldonium on post-ischemic recovery. Meldonium had no significant effect on blood glucose concentrations or on baseline cardiac function. However, hyperpolarized magnetic resonance revealed that meldonium treatment elevated pyruvate dehydrogenase flux by 3.1-fold and 1.2-fold in diabetic and control animals, respectively, suggesting an increase in cardiac glucose oxidation. Hyperpolarized magnetic resonance further demonstrated that meldonium reduced the normalized acetylcarnitine signal by 2.1-fold in both diabetic and control animals. The increase in pyruvate dehydrogenase flux in vivo was accompanied by an improvement in post-ischemic function ex vivo, as meldonium elevated the rate pressure product by 1.3-fold and 1.5-fold in the control and diabetic animals, respectively. In conclusion, meldonium improves in vivo pyruvate dehydrogenase flux in the diabetic heart, contributing to improved cardiac recovery after ischemia.
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Affiliation(s)
- Dragana Savic
- Cardiac Metabolism Research Group (CMRG), Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine, Radcliffe Department of MedicineUniversity of OxfordOxfordUK
| | - Vicky Ball
- Cardiac Metabolism Research Group (CMRG), Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Lorenz Holzner
- Department of Physiology, Development and NeuroscienceUniversity of CambridgeCambridgeUK
| | - David Hauton
- Cardiac Metabolism Research Group (CMRG), Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
- Metabolomics Research Group, Department of ChemistryUniversity of OxfordOxfordUK
| | - Kerstin N. Timm
- Cardiac Metabolism Research Group (CMRG), Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - M. Kate Curtis
- Cardiac Metabolism Research Group (CMRG), Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Lisa C. Heather
- Cardiac Metabolism Research Group (CMRG), Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Damian J. Tyler
- Cardiac Metabolism Research Group (CMRG), Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine, Radcliffe Department of MedicineUniversity of OxfordOxfordUK
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6
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Savic D, Ball V, Curtis MK, Sousa Fialho MDL, Timm KN, Hauton D, West J, Griffin J, Heather LC, Tyler DJ. L-Carnitine Stimulates In Vivo Carbohydrate Metabolism in the Type 1 Diabetic Heart as Demonstrated by Hyperpolarized MRI. Metabolites 2021; 11:metabo11030191. [PMID: 33806953 PMCID: PMC8004902 DOI: 10.3390/metabo11030191] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 03/15/2021] [Accepted: 03/19/2021] [Indexed: 01/25/2023] Open
Abstract
The diabetic heart is energetically and metabolically abnormal, with increased fatty acid oxidation and decreased glucose oxidation. One factor contributing to the metabolic dysfunction in diabetes may be abnormal handling of acetyl and acyl groups by the mitochondria. L-carnitine is responsible for their transfer across the mitochondrial membrane, therefore, supplementation with L-carnitine may provide a route to improve the metabolic state of the diabetic heart. The primary aim of this study was to use hyperpolarized magnetic resonance imaging (MRI) to investigate the effects of L-carnitine supplementation on the in vivo metabolism of [1-13C]pyruvate in diabetes. Male Wistar rats were injected with either vehicle or streptozotocin (55 mg/kg) to induce type-1 diabetes. Three weeks of daily i.p. treatment with either saline or L-carnitine (3 g/kg/day) was subsequently undertaken. In vivo cardiac function and metabolism were assessed with CINE and hyperpolarized MRI, respectively. L-carnitine supplementation prevented the progression of hyperglycemia, which was observed in untreated streptozotocin injected animals and led to reductions in plasma triglyceride and ß-hydroxybutyrate concentrations. Hyperpolarized MRI revealed that L-carnitine treatment elevated pyruvate dehydrogenase flux by 3-fold in the diabetic animals, potentially through increased buffering of excess acetyl-CoA units in the mitochondria. Improved functional recovery following ischemia was also observed in the L-carnitine treated diabetic animals.
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Affiliation(s)
- Dragana Savic
- Cardiac Metabolism Research Group, Department of Physiology Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK; (V.B.); (M.K.C.); (M.d.L.S.F.); (K.N.T.); (D.H.); (L.C.H.); (D.J.T.)
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford OX1 3PT, UK
- Correspondence:
| | - Vicky Ball
- Cardiac Metabolism Research Group, Department of Physiology Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK; (V.B.); (M.K.C.); (M.d.L.S.F.); (K.N.T.); (D.H.); (L.C.H.); (D.J.T.)
| | - M. Kate Curtis
- Cardiac Metabolism Research Group, Department of Physiology Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK; (V.B.); (M.K.C.); (M.d.L.S.F.); (K.N.T.); (D.H.); (L.C.H.); (D.J.T.)
| | - Maria da Luz Sousa Fialho
- Cardiac Metabolism Research Group, Department of Physiology Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK; (V.B.); (M.K.C.); (M.d.L.S.F.); (K.N.T.); (D.H.); (L.C.H.); (D.J.T.)
| | - Kerstin N. Timm
- Cardiac Metabolism Research Group, Department of Physiology Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK; (V.B.); (M.K.C.); (M.d.L.S.F.); (K.N.T.); (D.H.); (L.C.H.); (D.J.T.)
- Department of Pharmacology, University of Oxford, Oxford OX1 3PT, UK
| | - David Hauton
- Cardiac Metabolism Research Group, Department of Physiology Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK; (V.B.); (M.K.C.); (M.d.L.S.F.); (K.N.T.); (D.H.); (L.C.H.); (D.J.T.)
- Metabolomics Research Group, Department of Chemistry, University of Oxford, Oxford OX1 3PT, UK
| | - James West
- Department of Medicine, University of Cambridge, Cambridge CB2 1TN, UK;
| | - Julian Griffin
- Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College London, London SW7 2AZ, UK;
| | - Lisa C. Heather
- Cardiac Metabolism Research Group, Department of Physiology Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK; (V.B.); (M.K.C.); (M.d.L.S.F.); (K.N.T.); (D.H.); (L.C.H.); (D.J.T.)
| | - Damian J. Tyler
- Cardiac Metabolism Research Group, Department of Physiology Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK; (V.B.); (M.K.C.); (M.d.L.S.F.); (K.N.T.); (D.H.); (L.C.H.); (D.J.T.)
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford OX1 3PT, UK
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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: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 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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8
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Timm KN, Ball V, Miller JJ, Savic D, West JA, Griffin JL, Tyler DJ. Metabolic Effects of Doxorubicin on the Rat Liver Assessed With Hyperpolarized MRI and Metabolomics. Front Physiol 2021; 12:782745. [PMID: 35069242 PMCID: PMC8766499 DOI: 10.3389/fphys.2021.782745] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 12/13/2021] [Indexed: 11/30/2022] Open
Abstract
Doxorubicin (DOX) is a successful chemotherapeutic widely used for the treatment of a range of cancers. However, DOX can have serious side-effects, with cardiotoxicity and hepatotoxicity being the most common events. Oxidative stress and changes in metabolism and bioenergetics are thought to be at the core of these toxicities. We have previously shown in a clinically-relevant rat model that a low DOX dose of 2 mg kg-1 week-1 for 6 weeks does not lead to cardiac functional decline or changes in cardiac carbohydrate metabolism, assessed with hyperpolarized [1-13C]pyruvate magnetic resonance spectroscopy (MRS). We now set out to assess whether there are any signs of liver damage or altered liver metabolism using this subclinical model. We found no increase in plasma alanine aminotransferase (ALT) activity, a measure of liver damage, following DOX treatment in rats at any time point. We also saw no changes in liver carbohydrate metabolism, using hyperpolarized [1-13C]pyruvate MRS. However, using metabolomic analysis of liver metabolite extracts at the final time point, we found an increase in most acyl-carnitine species as well as increases in high energy phosphates, citrate and markers of oxidative stress. This may indicate early signs of steatohepatitis, with increased and decompensated fatty acid uptake and oxidation, leading to oxidative stress.
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Affiliation(s)
- Kerstin N. Timm
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
- *Correspondence: Kerstin N. Timm,
| | - Vicky Ball
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Jack J. Miller
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
- Department of Physics, University of Oxford, Oxford, United Kingdom
- Oxford Centre for Clinical Magnetic Resonance Research, John Radcliffe Hospital, Oxford, United Kingdom
- The MR Research Center, The PET Centre, Aarhus University Hospital, Aarhus University, Aarhus, Denmark
| | - Dragana Savic
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
- Oxford Centre for Clinical Magnetic Resonance Research, John Radcliffe Hospital, Oxford, United Kingdom
| | - James A. West
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
| | - Julian L. Griffin
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
- Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Damian J. Tyler
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
- Oxford Centre for Clinical Magnetic Resonance Research, John Radcliffe Hospital, Oxford, United Kingdom
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9
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Lutzweiler G, Barthes J, Charles AL, Ball V, Louis B, Geny B, Vrana NE. Improving the colonization and functions of Wharton's Jelly-derived mesenchymal stem cells by a synergetic combination of porous polyurethane scaffold with an albumin-derived hydrogel. ACTA ACUST UNITED AC 2020; 16:015005. [PMID: 33300500 DOI: 10.1088/1748-605x/abaf05] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The development of neo-tissues assisted by artificial scaffolds is continually progressing, but the reproduction of the extracellular environment surrounding cells is quite complex. While synthetic scaffolds can support cell growth, they lack biochemical cues that can prompt cell proliferation or differentiation. In this study, Wharton's Jelly-derived mesenchymal stem cells are seeded on a polyurethane (PU) scaffold combined with a hydrogel based on bovine serum albumin (BSA). BSA hydrogel is obtained through thermal treatment. While such treatment leads to partial unfolding of the protein, we show that the extent of denaturation is small enough to maintain its bioactivity, such as protein binding. Therefore, BSA provides a suitable playground for cells inside the scaffold, allowing higher spreading, proliferation and matrix secretions. Furthermore, the poor mechanical properties of the hydrogel are compensated for by the porous PU scaffold, whose architecture is well controlled. We show that even though PU by itself can allow cell adhesion and protein secretion, cell proliferation is 3.5 times higher in the PU + BSA scaffolds as compared to pure PU after 21 d, along with the non-collagenous protein secretions (389 versus 134 μmmg -1). Conversely, the secretion of sulphated glycosaminoglycans is 12.3-fold higher in the scaffold made solely of PU. Thereby, we propose a simple approach to generating a hybrid material composed of a combination of PU and BSA hydrogel as a promising scaffold for tissue regeneration.
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Affiliation(s)
- G Lutzweiler
- Institut National de la Santé et de la Recherche Medicale, UMR_S 1121, 11 rue Humann, 67085, Strasbourg Cedex, France
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10
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Timm KN, Perera C, Ball V, Henry JA, Miller JJ, Kerr M, West JA, Sharma E, Broxholme J, Logan A, Savic D, Dodd MS, Griffin JL, Murphy MP, Heather LC, Tyler DJ. Early detection of doxorubicin-induced cardiotoxicity in rats by its cardiac metabolic signature assessed with hyperpolarized MRI. Commun Biol 2020; 3:692. [PMID: 33214680 PMCID: PMC7678845 DOI: 10.1038/s42003-020-01440-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Accepted: 10/28/2020] [Indexed: 12/13/2022] Open
Abstract
Doxorubicin (DOX) is a widely used chemotherapeutic agent that can cause serious cardiotoxic side effects culminating in congestive heart failure (HF). There are currently no clinical imaging techniques or biomarkers available to detect DOX-cardiotoxicity before functional decline. Mitochondrial dysfunction is thought to be a key factor driving functional decline, though real-time metabolic fluxes have never been assessed in DOX-cardiotoxicity. Hyperpolarized magnetic resonance imaging (MRI) can assess real-time metabolic fluxes in vivo. Here we show that cardiac functional decline in a clinically relevant rat-model of DOX-HF is preceded by a change in oxidative mitochondrial carbohydrate metabolism, measured by hyperpolarized MRI. The decreased metabolic fluxes were predominantly due to mitochondrial loss and additional mitochondrial dysfunction, and not, as widely assumed hitherto, to oxidative stress. Since hyperpolarized MRI has been successfully translated into clinical trials this opens up the potential to test cancer patients receiving DOX for early signs of cardiotoxicity.
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Affiliation(s)
- Kerstin N Timm
- Department of Physiology Anatomy and Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford, OX1 3PT, UK.
| | - Charith Perera
- Department of Physiology Anatomy and Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford, OX1 3PT, UK
| | - Vicky Ball
- Department of Physiology Anatomy and Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford, OX1 3PT, UK
| | - John A Henry
- Department of Physiology Anatomy and Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford, OX1 3PT, UK
| | - Jack J Miller
- Department of Physiology Anatomy and Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford, OX1 3PT, UK
| | - Matthew Kerr
- Department of Physiology Anatomy and Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford, OX1 3PT, UK
| | - James A West
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Eshita Sharma
- Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Dr, Headington, Oxford, OX3 7BN, UK
| | - John Broxholme
- Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Dr, Headington, Oxford, OX3 7BN, UK
| | - Angela Logan
- MRC Mitochondrial Biology Unit, University of Cambridge, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY, UK
| | - Dragana Savic
- Department of Physiology Anatomy and Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford, OX1 3PT, UK
| | - Michael S Dodd
- Department of Physiology Anatomy and Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford, OX1 3PT, UK
| | - Julian L Griffin
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Michael P Murphy
- MRC Mitochondrial Biology Unit, University of Cambridge, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY, UK
| | - Lisa C Heather
- Department of Physiology Anatomy and Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford, OX1 3PT, UK
| | - Damian J Tyler
- Oxford Centre for Clinical Magnetic Resonance Research, John Radcliffe Hospital, Headington, Oxford, OX3 9DU, UK
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11
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Tyler A, Lau JYC, Ball V, Timm KN, Zhou T, Tyler DJ, Miller JJ. A 3D hybrid-shot spiral sequence for hyperpolarized 13 C imaging. Magn Reson Med 2020; 85:790-801. [PMID: 32894618 PMCID: PMC7611357 DOI: 10.1002/mrm.28462] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 06/30/2020] [Accepted: 07/14/2020] [Indexed: 01/30/2023]
Abstract
Purpose Hyperpolarized imaging experiments have conflicting requirements of high spatial, temporal, and spectral resolution. Spectral-spatial RF excitation has been shown to form an attractive magnetization-efficient method for hyperpolarized imaging, but the optimum readout strategy is not yet known. Methods In this work, we propose a novel 3D hybrid-shot spiral sequence which features two constant density regions that permit the retrospective reconstruction of either high spatial or high temporal resolution images post hoc, (adaptive spatiotemporal imaging) allowing greater flexibility in acquisition and reconstruction. Results We have implemented this sequence, both via simulation and on a preclinical scanner, to demonstrate its feasibility, in both a 1H phantom and with hyperpolarized 13C pyruvate in vivo. Conclusions This sequence forms an attractive method for acquiring hyperpolarized imaging datasets, providing adaptive spatiotemporal imaging to ameliorate the conflict of spatial and temporal resolution, with significant potential for clinical translation.
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Affiliation(s)
- Andrew Tyler
- Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, United Kingdom.,Oxford Centre for Clinical Cardiac Magnetic Resonance Research (OCMR), Level 0, John Radcliffe Hospital, Headington, United Kingdom
| | - Justin Y C Lau
- Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, United Kingdom.,Oxford Centre for Clinical Cardiac Magnetic Resonance Research (OCMR), Level 0, John Radcliffe Hospital, Headington, United Kingdom
| | - Vicky Ball
- Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, United Kingdom
| | - Kerstin N Timm
- Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, United Kingdom
| | - Tony Zhou
- Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, United Kingdom.,Oxford Centre for Clinical Cardiac Magnetic Resonance Research (OCMR), Level 0, John Radcliffe Hospital, Headington, United Kingdom
| | - Damian J Tyler
- Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, United Kingdom.,Oxford Centre for Clinical Cardiac Magnetic Resonance Research (OCMR), Level 0, John Radcliffe Hospital, Headington, United Kingdom
| | - Jack J Miller
- Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, United Kingdom.,Oxford Centre for Clinical Cardiac Magnetic Resonance Research (OCMR), Level 0, John Radcliffe Hospital, Headington, United Kingdom.,Department of Physics, Clarendon Laboratory, University of Oxford, Oxford, United Kingdom
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12
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Betts CA, McClorey G, Healicon R, Hammond SM, Manzano R, Muses S, Ball V, Godfrey C, Merritt TM, van Westering T, O'Donovan L, Wells KE, Gait MJ, Wells DJ, Tyler D, Wood MJ. Cmah-dystrophin deficient mdx mice display an accelerated cardiac phenotype that is improved following peptide-PMO exon skipping treatment. Hum Mol Genet 2019; 28:396-406. [PMID: 30281092 PMCID: PMC6337703 DOI: 10.1093/hmg/ddy346] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Accepted: 09/21/2018] [Indexed: 01/14/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) is caused by loss of dystrophin protein, leading to progressive muscle weakness and premature death due to respiratory and/or cardiac complications. Cardiac involvement is characterized by progressive dilated cardiomyopathy, decreased fractional shortening and metabolic dysfunction involving reduced metabolism of fatty acids-the major cardiac metabolic substrate. Several mouse models have been developed to study molecular and pathological consequences of dystrophin deficiency, but do not recapitulate all aspects of human disease pathology and exhibit a mild cardiac phenotype. Here we demonstrate that Cmah (cytidine monophosphate-sialic acid hydroxylase)-deficient mdx mice (Cmah-/-;mdx) have an accelerated cardiac phenotype compared to the established mdx model. Cmah-/-;mdx mice display earlier functional deterioration, specifically a reduction in right ventricle (RV) ejection fraction and stroke volume (SV) at 12 weeks of age and decreased left ventricle diastolic volume with subsequent reduced SV compared to mdx mice by 24 weeks. They further show earlier elevation of cardiac damage markers for fibrosis (Ctgf), oxidative damage (Nox4) and haemodynamic load (Nppa). Cardiac metabolic substrate requirement was assessed using hyperpolarized magnetic resonance spectroscopy indicating increased in vivo glycolytic flux in Cmah-/-;mdx mice. Early upregulation of mitochondrial genes (Ucp3 and Cpt1) and downregulation of key glycolytic genes (Pdk1, Pdk4, Ppara), also denote disturbed cardiac metabolism and shift towards glucose utilization in Cmah-/-;mdx mice. Moreover, we show long-term treatment with peptide-conjugated exon skipping antisense oligonucleotides (20-week regimen), resulted in 20% cardiac dystrophin protein restoration and significantly improved RV cardiac function. Therefore, Cmah-/-;mdx mice represent an appropriate model for evaluating cardiac benefit of novel DMD therapeutics.
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Affiliation(s)
- Corinne A Betts
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford, UK
| | - Graham McClorey
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford, UK
| | - Richard Healicon
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford, UK
| | - Suzan M Hammond
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford, UK
| | - Raquel Manzano
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford, UK
| | - Sofia Muses
- Department of Comparative Biomedical Sciences, Royal Veterinary College, Royal College Street, London, UK
| | - Vicky Ball
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford, UK
| | - Caroline Godfrey
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford, UK
| | - Thomas M Merritt
- Clinical Biomanufacturing Facility, Nuffield Department of Clinical Medicine, University of Oxford, Old Road, Oxford, UK
| | - Tirsa van Westering
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford, UK
| | - Liz O'Donovan
- Medical Research Council, Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, UK
| | - Kim E Wells
- Department of Comparative Biomedical Sciences, Royal Veterinary College, Royal College Street, London, UK
| | - Michael J Gait
- Medical Research Council, Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, UK
| | - Dominic J Wells
- Department of Comparative Biomedical Sciences, Royal Veterinary College, Royal College Street, London, UK
| | - Damian Tyler
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford, UK
| | - Matthew J Wood
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford, UK
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13
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Le Page LM, Rider OJ, Lewis AJ, Noden V, Kerr M, Giles L, Ambrose LJ, Ball V, Mansor L, Heather LC, Tyler DJ. Assessing the effect of hypoxia on cardiac metabolism using hyperpolarized 13 C magnetic resonance spectroscopy. NMR Biomed 2019; 32:e4099. [PMID: 31090979 PMCID: PMC6619452 DOI: 10.1002/nbm.4099] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 02/14/2019] [Accepted: 03/06/2019] [Indexed: 05/03/2023]
Abstract
Hypoxia plays a role in many diseases and can have a wide range of effects on cardiac metabolism depending on the extent of the hypoxic insult. Noninvasive imaging methods could shed valuable light on the metabolic effects of hypoxia on the heart in vivo. Hyperpolarized carbon-13 magnetic resonance spectroscopy (HP 13 C MRS) in particular is an exciting technique for imaging metabolism that could provide such information. The aim of our work was, therefore, to establish whether hyperpolarized 13 C MRS can be used to assess the in vivo heart's metabolism of pyruvate in response to systemic acute and chronic hypoxic exposure. Groups of healthy male Wistar rats were exposed to either acute (30 minutes), 1 week or 3 weeks of hypoxia. In vivo MRS of hyperpolarized [1-13 C] pyruvate was carried out along with assessments of physiological parameters and ejection fraction. Hematocrit was elevated after 1 week and 3 weeks of hypoxia. 30 minutes of hypoxia resulted in a significant reduction in pyruvate dehydrogenase (PDH) flux, whereas 1 or 3 weeks of hypoxia resulted in a PDH flux that was not different to normoxic animals. Conversion of hyperpolarized [1-13 C] pyruvate into [1-13 C] lactate was elevated following acute hypoxia, suggestive of enhanced anaerobic glycolysis. Elevated HP pyruvate to lactate conversion was also seen at the one week timepoint, in concert with an increase in lactate dehydrogenase (LDH) expression. Following three weeks of hypoxic exposure, cardiac metabolism of pyruvate was comparable with that observed in normoxia. We have successfully visualized the effects of systemic hypoxia on cardiac metabolism of pyruvate using hyperpolarized 13 C MRS, with differences observed following 30 minutes and 1 week of hypoxia. This demonstrates the potential of in vivo hyperpolarized 13 C MRS data for assessing the cardiometabolic effects of hypoxia in disease.
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Affiliation(s)
- Lydia M. Le Page
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
- Department of Physical Therapy and Rehabilitation ScienceUniversity of CaliforniaSan FranciscoSan FranciscoUSA
- Department of Radiology and Biomedical ImagingUniversity of CaliforniaSan FranciscoSan FranciscoUSA
| | - Oliver J. Rider
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular MedicineUniversity of OxfordOxfordUK
| | - Andrew J. Lewis
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular MedicineUniversity of OxfordOxfordUK
| | - Victoria Noden
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Matthew Kerr
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Lucia Giles
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Lucy J.A. Ambrose
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Vicky Ball
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Latt Mansor
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Lisa C. Heather
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Damian J. Tyler
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular MedicineUniversity of OxfordOxfordUK
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14
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Miller JJ, Lau AZ, Nielsen PM, McMullen-Klein G, Lewis AJ, Jespersen NR, Ball V, Gallagher FA, Carr CA, Laustsen C, Bøtker HE, Tyler DJ, Schroeder MA. Hyperpolarized [1,4- 13C 2]Fumarate Enables Magnetic Resonance-Based Imaging of Myocardial Necrosis. JACC Cardiovasc Imaging 2018; 11:1594-1606. [PMID: 29248653 PMCID: PMC6231534 DOI: 10.1016/j.jcmg.2017.09.020] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Revised: 09/19/2017] [Accepted: 09/21/2017] [Indexed: 12/12/2022]
Abstract
OBJECTIVES The aim of this study was to determine if hyperpolarized [1,4-13C2]malate imaging could measure cardiomyocyte necrosis after myocardial infarction (MI). BACKGROUND MI is defined by an acute burst of cellular necrosis and the subsequent cascade of structural and functional adaptations. Quantifying necrosis in the clinic after MI remains challenging. Magnetic resonance-based detection of the conversion of hyperpolarized [1,4-13C2]fumarate to [1,4-13C2]malate, enabled by disrupted cell membrane integrity, has measured cellular necrosis in vivo in other tissue types. Our aim was to determine whether hyperpolarized [1,4-13C2]malate imaging could measure necrosis after MI. METHODS Isolated perfused hearts were given hyperpolarized [1,4-13C2]fumarate at baseline, immediately after 20 min of ischemia, and after 45 min of reperfusion. Magnetic resonance spectroscopy measured conversion into [1,4-13C2]malate. Left ventricular function and energetics were monitored throughout the protocol, buffer samples were collected and hearts were preserved for further analyses. For in vivo studies, magnetic resonance spectroscopy and a novel spatial-spectral magnetic resonance imaging sequence were implemented to assess cardiomyocyte necrosis in rats, 1 day and 1 week after cryo-induced MI. RESULTS In isolated hearts, [1,4-13C2]malate production became apparent after 45 min of reperfusion, and increased 2.7-fold compared with baseline. Expression of dicarboxylic acid transporter genes were negligible in healthy and reperfused hearts, and lactate dehydrogenase release and infarct size were significantly increased in reperfused hearts. Nonlinear regression revealed that [1,4-13C2]malate production was induced when adenosine triphosphate was depleted by >50%, below 5.3 mmol/l (R2 = 0.904). In vivo, the quantity of [1,4-13C2]malate visible increased 82-fold over controls 1 day after infarction, maintaining a 31-fold increase 7 days post-infarct. [1,4-13C2]Malate could be resolved using hyperpolarized magnetic resonance imaging in the infarct region one day after MI; [1,4-13C2]malate was not visible in control hearts. CONCLUSIONS Malate production in the infarcted heart appears to provide a specific probe of necrosis acutely after MI, and for at least 1 week afterward. This technique could offer an alternative noninvasive method to measure cellular necrosis in heart disease, and warrants further investigation in patients.
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Affiliation(s)
- Jack J Miller
- Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, United Kingdom; Department of Physics, University of Oxford, Oxford, United Kingdom; University of Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Angus Z Lau
- Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, United Kingdom; University of Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom; Physical Sciences, Sunnybrook Research Institute, Toronto, Canada
| | - Per Mose Nielsen
- Department of Clinical Medicine, Aarhus University Hospital Skejby, Aarhus, Denmark
| | - Giles McMullen-Klein
- Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, United Kingdom
| | - Andrew J Lewis
- University of Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | | | - Vicky Ball
- Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, United Kingdom
| | - Ferdia A Gallagher
- Department of Radiology, University of Cambridge, Cambridge, United Kingdom
| | - Carolyn A Carr
- Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, United Kingdom
| | - Christoffer Laustsen
- Department of Clinical Medicine, Aarhus University Hospital Skejby, Aarhus, Denmark
| | - Hans Erik Bøtker
- Department of Clinical Medicine, Aarhus University Hospital Skejby, Aarhus, Denmark
| | - Damian J Tyler
- Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, United Kingdom; University of Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Marie A Schroeder
- Department of Clinical Medicine, Aarhus University Hospital Skejby, Aarhus, Denmark.
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15
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Timm KN, Apps A, Miller JJ, Ball V, Chong C, Dodd MS, Tyler DJ. Assessing the optimal preparation strategy to minimize the variability of cardiac pyruvate dehydrogenase flux measurements with hyperpolarized MRS. NMR Biomed 2018; 31:e3992. [PMID: 30040147 PMCID: PMC6175301 DOI: 10.1002/nbm.3992] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 06/06/2018] [Accepted: 06/07/2018] [Indexed: 05/11/2023]
Abstract
Hyperpolarized [1-13 C] pyruvate MRS can measure cardiac pyruvate dehydrogenase (PDH) flux in vivo through 13 C-label incorporation into bicarbonate. Using this technology, substrate availability as well as pathology have been shown to modulate PDH flux. Clinical protocols attempt to standardize PDH flux with oral glucose loading prior to scanning, while rodents in preclinical studies are usually scanned in the fed state. We aimed to establish which strategy was optimal to maximize PDH flux and minimize its variability in both control and Type II diabetic rats, without affecting the pathological variation being assessed. We found similar variances in the bicarbonate to pyruvate ratio, reflecting PDH flux, in fed and fasted/glucose-loaded animals, which showed no statistically significant differences. Furthermore, fasting/glucose loading did not alter the low PDH flux seen in Type II diabetic rats. Overall this suggests that preclinical cardiac hyperpolarized magnetic resonance studies could be performed either in the fed or in the fasted/glucose-loaded state. Centres planning to start new clinical studies with cardiac hyperpolarized magnetic resonance in man may find it beneficial to run small proof-of-concept trials to determine whether metabolic standardizations by oral or intravenous glucose load are beneficial compared with scanning patients in the fed state.
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Affiliation(s)
| | - Andrew Apps
- Oxford Centre for Clinical Magnetic Resonance Research, John Radcliffe HospitalOxfordUK
| | - Jack J. Miller
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordUK
- Oxford Centre for Clinical Magnetic Resonance Research, John Radcliffe HospitalOxfordUK
- Clarendon Laboratory, Department of PhysicsUniversity of OxfordUK
| | - Vicky Ball
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordUK
| | - Cher‐Rin Chong
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordUK
| | - Michael S. Dodd
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordUK
| | - Damian J. Tyler
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordUK
- Oxford Centre for Clinical Magnetic Resonance Research, John Radcliffe HospitalOxfordUK
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16
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Timm K, Perera C, Ball V, Henry J, West J, Kerr M, Logan A, Griffin J, Murphy M, Heather L, Tyler D. Investigating real-time metabolic flux changes in a rat model of doxorubicin-induced cardiotoxicity using hyperpolarized 13C magnetic resonance spectroscopy. J Mol Cell Cardiol 2018. [DOI: 10.1016/j.yjmcc.2018.05.105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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17
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Rohm M, Savic D, Ball V, Curtis MK, Bonham S, Fischer R, Legrave N, MacRae JI, Tyler DJ, Ashcroft FM. Cardiac Dysfunction and Metabolic Inflexibility in a Mouse Model of Diabetes Without Dyslipidemia. Diabetes 2018; 67:1057-1067. [PMID: 29610263 DOI: 10.2337/db17-1195] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 03/12/2018] [Indexed: 11/13/2022]
Abstract
Diabetes is a well-established risk factor for heart disease, leading to impaired cardiac function and a metabolic switch toward fatty acid usage. In this study, we investigated if hyperglycemia/hypoinsulinemia in the absence of dyslipidemia is sufficient to drive these changes and if they can be reversed by restoring euglycemia. Using the βV59M mouse model, in which diabetes can be rapidly induced and reversed, we show that stroke volume and cardiac output were reduced within 2 weeks of diabetes induction. Flux through pyruvate dehydrogenase was decreased, as measured in vivo by hyperpolarized [1-13C]pyruvate MRS. Metabolomics showed accumulation of pyruvate, lactate, alanine, tricarboxyclic acid cycle metabolites, and branched-chain amino acids. Myristic and palmitoleic acid were decreased. Proteomics revealed proteins involved in fatty acid metabolism were increased, whereas those involved in glucose metabolism decreased. Western blotting showed enhanced pyruvate dehydrogenase kinase 4 (PDK4) and uncoupling protein 3 (UCP3) expression. Elevated PDK4 and UCP3 and reduced pyruvate usage were present 24 h after diabetes induction. The observed effects were independent of dyslipidemia, as mice showed no evidence of elevated serum triglycerides or lipid accumulation in peripheral organs (including the heart). The effects of diabetes were reversible, as glibenclamide therapy restored euglycemia, cardiac metabolism and function, and PDK4/UCP3 levels.
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Affiliation(s)
- Maria Rohm
- Department of Physiology, Anatomy and Genetics and OXION, University of Oxford, Oxford, U.K
| | - Dragana Savic
- Cardiac Metabolism Research Group, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, U.K
| | - Vicky Ball
- Cardiac Metabolism Research Group, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, U.K
| | - M Kate Curtis
- Cardiac Metabolism Research Group, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, U.K
| | - Sarah Bonham
- Discovery Proteomics Facility, Target Discovery Institute, University of Oxford, Oxford, U.K
| | - Roman Fischer
- Discovery Proteomics Facility, Target Discovery Institute, University of Oxford, Oxford, U.K
| | | | | | - Damian J Tyler
- Cardiac Metabolism Research Group, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, U.K
| | - Frances M Ashcroft
- Department of Physiology, Anatomy and Genetics and OXION, University of Oxford, Oxford, U.K.
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18
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Lakhal-Littleton S, Wolna M, Chung YJ, Christian H, Heather L, Brescia M, Ball V, Diaz R, Santos A, Biggs D, Clarke K, Davies B, Robbins P. 204 The cardiac hepcidin/ferroportin axis is essntial for cardiac iron homeostasis and function. Heart 2017. [DOI: 10.1136/heartjnl-2017-311726.202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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19
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Le Page LM, Ball DR, Ball V, Dodd MS, Miller JJ, Heather LC, Tyler DJ. Simultaneous in vivo assessment of cardiac and hepatic metabolism in the diabetic rat using hyperpolarized MRS. NMR Biomed 2016; 29:1759-1767. [PMID: 27779334 PMCID: PMC5132204 DOI: 10.1002/nbm.3656] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 08/24/2016] [Accepted: 09/12/2016] [Indexed: 05/07/2023]
Abstract
Understanding and assessing diabetic metabolism is vital for monitoring disease progression and improving treatment of patients. In vivo assessments, using MRI and MRS, provide non-invasive and accurate measurements, and the development of hyperpolarized 13 C spectroscopy in particular has been demonstrated to provide valuable metabolic data in real time. Until now, studies have focussed on individual organs. However, diabetes is a systemic disease affecting multiple tissues in the body. Therefore, we have developed a technique to simultaneously measure metabolism in both the heart and liver during a single acquisition. A hyperpolarized 13 C MRS protocol was developed to allow acquisition of metabolic data from the heart and liver during a single scan. This protocol was subsequently used to assess metabolism in the heart and liver of seven control male Wistar rats and seven diabetic rats (diabetes was induced by three weeks of high-fat feeding and a 30 mg/kg injection of streptozotocin). Using our new acquisition, we observed decreased cardiac and hepatic pyruvate dehydrogenase flux in our diabetic rat model. These diabetic rats also had increased blood glucose levels, decreased insulin, and increased hepatic triglycerides. Decreased production of hepatic [1-13 C]alanine was observed in the diabetic group, but this change was not present in the hearts of the same diabetic animals. We have demonstrated the ability to measure cardiac and hepatic metabolism simultaneously, with sufficient sensitivity to detect metabolic alterations in both organs. Further, we have non-invasively observed the different reactions of the heart and liver to the metabolic challenge of diabetes.
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Affiliation(s)
- Lydia M. Le Page
- Cardiac Metabolism Research Group, Department of Physiology Anatomy and GeneticsUniversity of OxfordOxfordUK
- Department of Radiology and Biomedical ImagingUniversity of CaliforniaSan FranciscoCAUSA
| | - Daniel R. Ball
- Cardiac Metabolism Research Group, Department of Physiology Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Vicky Ball
- Cardiac Metabolism Research Group, Department of Physiology Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Michael S. Dodd
- Cardiac Metabolism Research Group, Department of Physiology Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Jack J. Miller
- Cardiac Metabolism Research Group, Department of Physiology Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Lisa C. Heather
- Cardiac Metabolism Research Group, Department of Physiology Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Damian J. Tyler
- Cardiac Metabolism Research Group, Department of Physiology Anatomy and GeneticsUniversity of OxfordOxfordUK
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20
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Lakhal-Littleton S, Wolna M, Chung YJ, Christian HC, Heather LC, Brescia M, Ball V, Diaz R, Santos A, Biggs D, Clarke K, Davies B, Robbins PA. An essential cell-autonomous role for hepcidin in cardiac iron homeostasis. eLife 2016; 5. [PMID: 27897970 PMCID: PMC5176354 DOI: 10.7554/elife.19804] [Citation(s) in RCA: 131] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 11/24/2016] [Indexed: 12/16/2022] Open
Abstract
Hepcidin is the master regulator of systemic iron homeostasis. Derived primarily from the liver, it inhibits the iron exporter ferroportin in the gut and spleen, the sites of iron absorption and recycling respectively. Recently, we demonstrated that ferroportin is also found in cardiomyocytes, and that its cardiac-specific deletion leads to fatal cardiac iron overload. Hepcidin is also expressed in cardiomyocytes, where its function remains unknown. To define the function of cardiomyocyte hepcidin, we generated mice with cardiomyocyte-specific deletion of hepcidin, or knock-in of hepcidin-resistant ferroportin. We find that while both models maintain normal systemic iron homeostasis, they nonetheless develop fatal contractile and metabolic dysfunction as a consequence of cardiomyocyte iron deficiency. These findings are the first demonstration of a cell-autonomous role for hepcidin in iron homeostasis. They raise the possibility that such function may also be important in other tissues that express both hepcidin and ferroportin, such as the kidney and the brain. DOI:http://dx.doi.org/10.7554/eLife.19804.001 Many proteins inside cells require iron to work properly, and so this mineral is an essential part of the diets of most mammals. However, because too much iron in the body is also bad for health, mammals possess several proteins whose role is to maintain the balance of iron. Two proteins in particular, called hepcidin and ferroportin, are thought to be important in this process. Some ferroportin is found in the cells that line the gut (where iron is absorbed into the body) and is required to release this iron into the bloodstream. It is also found in the spleen, which is where iron is removed from old red blood cells so that it can be recycled. The liver produces hepcidin to control when ferroportin is active in the gut and spleen. Both hepcidin and ferroportin are also found in heart cells. In 2015, a study reported that that heart ferroportin plays an important role in heart activity. However, it was not clear what role hepcidin plays in this organ. Now, Lakhal-Littleton et al. – including many of the researchers from the previous work – have genetically engineered mice such that they specifically lacked heart hepcidin, or had a version of ferroportin in their heart that does not respond to hepcidin. The experiments show that these changes caused fatal heart failure in the mice because ferroportin releases iron from heart cells in an uncontrolled manner. Lakhal-Littleton et al. were able to prevent heart failure by injecting the animals with iron directly into the bloodstream. These findings show that hepcidin produced outside the liver has a role in controlling the levels of iron in the body’s organs. Other organs such as the brain, kidney and placenta all have their own forms of hepcidin and ferroportin; further work could investigate the roles of these proteins. Finally, another challenge for the future will be to test whether new drugs that are being developed to block or mimic hepcidin from the liver have the potential to treat heart conditions in humans. DOI:http://dx.doi.org/10.7554/eLife.19804.002
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Affiliation(s)
- Samira Lakhal-Littleton
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Magda Wolna
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Yu Jin Chung
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Helen C Christian
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Lisa C Heather
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Marcella Brescia
- 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
| | - Rebeca Diaz
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Ana Santos
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Daniel Biggs
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Kieran Clarke
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Benjamin Davies
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Peter A Robbins
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
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Kouzouna A, Gilchrist FJ, Ball V, Kyriacou T, Henderson J, Pandyan AD, Lenney W. A systematic review of early life factors which adversely affect subsequent lung function. Paediatr Respir Rev 2016; 20:67-75. [PMID: 27197758 DOI: 10.1016/j.prrv.2016.03.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 03/08/2016] [Indexed: 01/15/2023]
Abstract
It has been known for many years that multiple early life factors can adversely affect lung function and future respiratory health. This is the first systematic review to attempt to analyse all these factors simultaneously. We adhered to strict a priori criteria for inclusion and exclusion of studies. The initial search yielded 29,351 citations of which 208 articles were reviewed in full and 25 were included in the review. This included 6 birth cohorts and 19 longitudinal population studies. The 25 studies reported the effect of 74 childhood factors (on their own or in combinations with other factors) on subsequent lung function reported as percent predicted forced expiration in one second (FEV1). The childhood factors that were associated with a significant reduction in future FEV1 could be grouped as: early infection, bronchial hyper-reactivity (BHR) / airway lability, a diagnosis of asthma, wheeze, family history of atopy or asthma, respiratory symptoms and prematurity / low birth weight. A complete mathematical model will only be possible if the raw data from all previous studies is made available. This highlights the need for increased cooperation between researchers and the need for international consensus about the outcome measures for future longitudinal studies.
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Affiliation(s)
- A Kouzouna
- Institute of Science and Technology in Medicine, Keele University, Staffordshire, ST5 5BG, UK; School of Health Rehabilitation, Keele University, Staffordshire, ST5 5BG, UK
| | - F J Gilchrist
- Institute of Science and Technology in Medicine, Keele University, Staffordshire, ST5 5BG, UK; Royal Stoke University Hospital, Stoke on Trent, Newcastle Road, ST4 6QG
| | - V Ball
- School of Health Rehabilitation, Keele University, Staffordshire, ST5 5BG, UK
| | - T Kyriacou
- School of Computing, Keele University, Staffordshire, ST5 5BG, UK
| | - J Henderson
- School of Social and Community Medicine, University of Bristol, Bristol, BS8 2BN, UK
| | - A D Pandyan
- Institute of Science and Technology in Medicine, Keele University, Staffordshire, ST5 5BG, UK; School of Health Rehabilitation, Keele University, Staffordshire, ST5 5BG, UK
| | - W Lenney
- Institute of Science and Technology in Medicine, Keele University, Staffordshire, ST5 5BG, UK; Royal Stoke University Hospital, Stoke on Trent, Newcastle Road, ST4 6QG.
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Miller JJ, Lau AZ, Teh I, Schneider JE, Kinchesh P, Smart S, Ball V, Sibson NR, Tyler DJ. Robust and high resolution hyperpolarized metabolic imaging of the rat heart at 7 T with 3D spectral-spatial EPI. Magn Reson Med 2016; 75:1515-24. [PMID: 25991606 PMCID: PMC4556070 DOI: 10.1002/mrm.25730] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 02/27/2015] [Accepted: 03/22/2015] [Indexed: 12/21/2022]
Abstract
PURPOSE Hyperpolarized metabolic imaging has the potential to revolutionize the diagnosis and management of diseases where metabolism is dysregulated, such as heart disease. We investigated the feasibility of imaging rodent myocardial metabolism at high resolution at 7 T. METHODS We present here a fly-back spectral-spatial radiofrequency pulse that sidestepped maximum gradient strength requirements and enabled high resolution metabolic imaging of the rodent myocardium. A 3D echo-planar imaging readout followed, with centric ordered z-phase encoding. The cardiac gated sequence was used to image metabolism in rodents whose metabolic state had been manipulated by being fasted, fed, or fed and given the pyruvate dehydrogenase kinase inhibitor dichloroacetate. RESULTS We imaged hyperpolarized metabolites with a spatial resolution of 2×2×3.8 mm(3) and a temporal resolution of 1.8 s in the rat heart at 7 T. Significant differences in myocardial pyruvate dehydrogenase flux were observed between the three groups of animals, concomitant with the known biochemistry. CONCLUSION The proposed sequence was able to image in vivo metabolism with excellent spatial resolution in the rat heart. The field of view enabled the simultaneous multi-organ acquisition of metabolic information from the rat, which is of great utility for preclinical research in cardiovascular disease. Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance.
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Affiliation(s)
- Jack J. Miller
- Department of PhysicsClarendon LaboratoryUniversity of OxfordEnglandUK
- Department of PhysiologyAnatomy & GeneticsUniversity of OxfordEnglandUK
- Department of OncologyCancer Research UK and Medical Research Council Oxford Institute for Radiation OncologyUniversity of OxfordOxfordEnglandUK
| | - Angus Z. Lau
- Department of PhysiologyAnatomy & GeneticsUniversity of OxfordEnglandUK
- Division of Cardiovascular MedicineRadcliffe Department of MedicineUniversity of OxfordEnglandUK
| | - Irvin Teh
- Division of Cardiovascular MedicineRadcliffe Department of MedicineUniversity of OxfordEnglandUK
| | - Jürgen E. Schneider
- Division of Cardiovascular MedicineRadcliffe Department of MedicineUniversity of OxfordEnglandUK
| | - Paul Kinchesh
- Department of OncologyCancer Research UK and Medical Research Council Oxford Institute for Radiation OncologyUniversity of OxfordOxfordEnglandUK
| | - Sean Smart
- Department of OncologyCancer Research UK and Medical Research Council Oxford Institute for Radiation OncologyUniversity of OxfordOxfordEnglandUK
| | - Vicky Ball
- Department of PhysiologyAnatomy & GeneticsUniversity of OxfordEnglandUK
| | - Nicola R. Sibson
- Department of OncologyCancer Research UK and Medical Research Council Oxford Institute for Radiation OncologyUniversity of OxfordOxfordEnglandUK
| | - Damian J. Tyler
- Department of PhysiologyAnatomy & GeneticsUniversity of OxfordEnglandUK
- Division of Cardiovascular MedicineRadcliffe Department of MedicineUniversity of OxfordEnglandUK
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23
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Abstract
Tannic acid (TA), among other polyphenols, interacts strongly with proteins, in particular proline rich proteins, a mechanism which is at the origin of mouth astringency.
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Affiliation(s)
- C. Ringwald
- Institut National de la Santé et de la Recherche Médicale
- Unité Mixte de Recherche 1121
- 67085 Strasbourg Cedex
- France
| | - V. Ball
- Institut National de la Santé et de la Recherche Médicale
- Unité Mixte de Recherche 1121
- 67085 Strasbourg Cedex
- France
- Université de Strasbourg
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24
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Perbellini F, Gomes RSM, Vieira S, Buchanan D, Malandraki-Miller S, Bruyneel AAN, Sousa Fialho MDL, Ball V, Clarke K, Faggian G, Carr CA. Chronic High-Fat Feeding Affects the Mesenchymal Cell Population Expanded From Adipose Tissue but Not Cardiac Atria. Stem Cells Transl Med 2015; 4:1403-14. [PMID: 26518239 DOI: 10.5966/sctm.2015-0024] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Accepted: 09/14/2015] [Indexed: 02/07/2023] Open
Abstract
UNLABELLED Mesenchymal stem cells offer a promising approach to the treatment of myocardial infarction and prevention of heart failure. However, in the clinic, cells will be isolated from patients who may be suffering from comorbidities such as obesity and diabetes, which are known to adversely affect progenitor cells. Here we determined the effect of a high-fat diet (HFD) on mesenchymal stem cells from cardiac and adipose tissues. Mice were fed a HFD for 4 months, after which cardiosphere-derived cells (CDCs) were cultured from atrial tissue and adipose-derived mesenchymal cells (ADMSCs) were isolated from epididymal fat depots. HFD raised body weight, fasted plasma glucose, lactate, and insulin. Ventricle and liver tissue of HFD-fed mice showed protein changes associated with an early type 2 diabetic phenotype. At early passages, more ADMSCs were obtained from HFD-fed mice than from chow-fed mice, whereas CDC number was not affected by HFD. Migratory and clonogenic capacity and release of vascular endothelial growth factor did not differ between cells from HFD- and chow-fed animals. CDCs from chow-fed and HFD-fed mice showed no differences in surface marker expression, whereas ADMSCs from HFD-fed mice contained more cells positive for CD105, DDR2, and CD45, suggesting a high component of endothelial, fibroblast, and hematopoietic cells. Both Noggin and transforming growth factor β-supplemented medium induced an early stage of differentiation in CDCs toward the cardiomyocyte phenotype. Thus, although chronic high-fat feeding increased the number of fibroblasts and hematopoietic cells within the ADMSC population, it left cardiac progenitor cells largely unaffected. SIGNIFICANCE Mesenchymal cells are a promising candidate cell source for restoring lost tissue and thereby preventing heart failure. In the clinic, cells are isolated from patients who may be suffering from comorbidities such as obesity and diabetes. This study examined the effect of a high-fat diet on mesenchymal cells from cardiac and adipose tissues. It was demonstrated that a high-fat diet did not affect cardiac progenitor cells but increased the number of fibroblasts and hematopoietic cells within the adipose-derived mesenchymal cell population.
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Affiliation(s)
- Filippo Perbellini
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom Department of Cardiac Surgery, University of Verona,Verona, Italy
| | - Renata S M Gomes
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Silvia Vieira
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Dougal Buchanan
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | | | - Arne A N Bruyneel
- 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
| | - Kieran Clarke
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Giuseppe Faggian
- Department of Cardiac Surgery, University of Verona,Verona, Italy
| | - Carolyn A Carr
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
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Le Page LM, Rider OJ, Lewis AJ, Ball V, Clarke K, Johansson E, Carr CA, Heather LC, Tyler DJ. Increasing Pyruvate Dehydrogenase Flux as a Treatment for Diabetic Cardiomyopathy: A Combined 13C Hyperpolarized Magnetic Resonance and Echocardiography Study. Diabetes 2015; 64:2735-43. [PMID: 25795215 PMCID: PMC4516266 DOI: 10.2337/db14-1560] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 03/16/2015] [Indexed: 01/02/2023]
Abstract
Although diabetic cardiomyopathy is widely recognized, there are no specific treatments available. Altered myocardial substrate selection has emerged as a candidate mechanism behind the development of cardiac dysfunction in diabetes. As pyruvate dehydrogenase (PDH) activity appears central to the balance of substrate use, we aimed to investigate the relationship between PDH flux and myocardial function in a rodent model of type 2 diabetes and to explore whether or not increasing PDH flux, with dichloroacetate, would restore the balance of substrate use and improve cardiac function. All animals underwent in vivo hyperpolarized [1-(13)C]pyruvate magnetic resonance spectroscopy and echocardiography to assess cardiac PDH flux and function, respectively. Diabetic animals showed significantly higher blood glucose levels (10.8 ± 0.7 vs. 8.4 ± 0.5 mmol/L), lower PDH flux (0.005 ± 0.001 vs. 0.017 ± 0.002 s(-1)), and significantly impaired diastolic function (transmitral early diastolic peak velocity/early diastolic myocardial velocity ratio [E/E'] 12.2 ± 0.8 vs. 20 ± 2), which are in keeping with early diabetic cardiomyopathy. Twenty-eight days of treatment with dichloroacetate restored PDH flux to normal levels (0.018 ± 0.002 s(-1)), reversed diastolic dysfunction (E/E' 14 ± 1), and normalized blood glucose levels (7.5 ± 0.7 mmol/L). The treatment of diabetes with dichloroacetate therefore restored the balance of myocardial substrate selection, reversed diastolic dysfunction, and normalized blood glucose levels. This suggests that PDH modulation could be a novel therapy for the treatment and/or prevention of diabetic cardiomyopathy.
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Affiliation(s)
- Lydia M Le Page
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, U.K
| | - Oliver J Rider
- Division of Cardiovascular Medicine, University of Oxford, Oxford, U.K
| | - Andrew J Lewis
- Division of Cardiovascular Medicine, University of Oxford, Oxford, U.K
| | - Vicky Ball
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, U.K
| | - Kieran Clarke
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, U.K
| | | | - Carolyn A Carr
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, U.K
| | - Lisa C Heather
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, U.K
| | - Damian J Tyler
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, U.K.
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26
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Seymour AML, Giles L, Ball V, Miller JJ, Clarke K, Carr CA, Tyler DJ. In vivo assessment of cardiac metabolism and function in the abdominal aortic banding model of compensated cardiac hypertrophy. Cardiovasc Res 2015; 106:249-60. [PMID: 25750189 PMCID: PMC4400188 DOI: 10.1093/cvr/cvv101] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Accepted: 03/02/2015] [Indexed: 01/22/2023] Open
Abstract
Aims Left ventricular hypertrophy is an adaptive response of the heart to chronic mechanical overload and can lead to functional deterioration and heart failure. Changes in cardiac energy metabolism are considered as key to the hypertrophic remodelling process. The concurrence of obesity and hypertrophy has been associated with contractile dysfunction, and this work therefore aimed to investigate the in vivo structural, functional, and metabolic remodelling that occurs in the hypertrophied heart in the setting of a high-fat, high-sucrose, Western diet (WD). Methods and results Following induction of cardiac hypertrophy through abdominal aortic banding, male Sprague Dawley rats were exposed to either a standard diet or a WD (containing 45% fat and 16% sucrose) for up to 14 weeks. Cardiac structural and functional characteristics were determined by CINE MRI, and in vivo metabolism was investigated using hyperpolarized 13C-labelled pyruvate. Cardiac hypertrophy was observed at all time points, irrespective of dietary manipulation, with no evidence of cardiac dysfunction. Pyruvate dehydrogenase flux was unchanged in the hypertrophied animals at any time point, but increased incorporation of the 13C label into lactate was observed by 9 weeks and maintained at 14 weeks, indicative of enhanced glycolysis. Conclusion Hypertrophied hearts revealed little evidence of a switch towards increased glucose oxidation but rather an uncoupling of glycolytic metabolism from glucose oxidation. This was maintained under conditions of dietary stress provided by a WD but, at this compensated phase of hypertrophy, did not result in any contractile dysfunction.
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Affiliation(s)
- Anne-Marie L Seymour
- School of Biological, Biomedical and Environmental Sciences, University of Hull, Hull HU6 7RX, UK
| | - Lucia Giles
- Department of Physiology, Anatomy and Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Vicky Ball
- Department of Physiology, Anatomy and Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Jack J Miller
- Department of Physiology, Anatomy and Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Kieran Clarke
- Department of Physiology, Anatomy and Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Carolyn A Carr
- Department of Physiology, Anatomy and Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Damian J Tyler
- Department of Physiology, Anatomy and Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
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Giles L, Ball V, Tyler DJ. THE EFFECTS OF ACUTE AND CHRONIC UP-REGULATION OF PYRUVATE DEHYDROGENASE IN THE HEART. Heart 2014. [DOI: 10.1136/heartjnl-2014-306916.34] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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28
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Cini N, Ball V. Polyphosphates as inorganic polyelectrolytes interacting with oppositely charged ions, polymers and deposited on surfaces: fundamentals and applications. Adv Colloid Interface Sci 2014; 209:84-97. [PMID: 24529970 DOI: 10.1016/j.cis.2014.01.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Revised: 01/12/2014] [Accepted: 01/13/2014] [Indexed: 12/01/2022]
Abstract
Polyphosphates are important but neglected polyelectrolytes that play a major role in biology and in surface science for the stabilization of colloids against flocculation and for the preservation of food. They are also known as "Calgon" ® and intensively used as additives in washing powders. This review aims to review recent developments in which linear polyphosphates are used for the design of new functional coatings using sol-gel processes and layer-by-layer deposition methods. All these methods rely on the high charge density of polyphosphates as inorganic polyelectrolytes, therefore the structure and properties of these molecules are also reviewed. New perspectives will also been given for the design of stimuli responsive coatings at the tiny frontier between biology and materials science.
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Affiliation(s)
- N Cini
- Technical University of Istanbul, Faculty of Science and Letters, Department of Chemistry, 34469 Maslak Istanbul, Turkey
| | - V Ball
- Université de Strasbourg, Faculté de Chirurgie Dentaire, 1 Place de l'Hôpital, 67000 Strasbourg, France; Institut National de la santé et de la Recherche Médicale, Unité Mixte de Recherche 1121, 11 rue Humann, 67085 Strasbourg Cedex, France.
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Abstract
The method of Tikhonov regularization is commonly used to obtain regularized solutions of ill-posed linear inverse problems. We use its natural connection to optimal Bayes estimators to determine optimal experimental designs that can be used with Tikhonov regularization; they are designed to control a measure of total relative efficiency. We present an iterative/semidefinite programming hybrid method to explore the configuration space efficiently. Two examples from geophysics are used to illustrate the type of applications to which the methodology can be applied.
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Affiliation(s)
- L Tenorio
- Applied Mathematics and Statistics, Colorado School of Mines, Golden, CO
| | - C Lucero
- Applied Mathematics and Statistics, Colorado School of Mines, Golden, CO
| | - V Ball
- Hess Corporation, Houston, TX
| | - L Horesh
- IBM T J Watson Research Center, Yorktown Heights, NY
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Ball DR, Rowlands B, Dodd MS, Le Page L, Ball V, Carr CA, Clarke K, Tyler DJ. Hyperpolarized butyrate: a metabolic probe of short chain fatty acid metabolism in the heart. Magn Reson Med 2013; 71:1663-9. [PMID: 23798473 PMCID: PMC4238803 DOI: 10.1002/mrm.24849] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Revised: 04/25/2013] [Accepted: 05/28/2013] [Indexed: 12/13/2022]
Abstract
Purpose Butyrate, a short chain fatty acid, was studied as a novel hyperpolarized substrate for use in dynamic nuclear polarization enhanced magnetic resonance spectroscopy experiments, to define the pathways of short chain fatty acid and ketone body metabolism in real time. Methods Butyrate was polarized via the dynamic nuclear polarization process and subsequently dissolved to generate an injectable metabolic substrate. Metabolism was initially assessed in the isolated perfused rat heart, followed by evaluation in the in vivo rat heart. Results Hyperpolarized butyrate was generated with a polarization level of 7% and was shown to have a T1 relaxation time of 20 s. These physical characteristics were sufficient to enable assessment of multiple steps in its metabolism, with the ketone body acetoacetate and several tricarboxylic acid cycle intermediates observed both in vitro and in vivo. Metabolite to butyrate ratios of 0.1–0.4% and 0.5–2% were observed in vitro and in vivo respectively, similar to levels previously observed with hyperpolarized [2-13C]pyruvate. Conclusions In this study, butyrate has been demonstrated to be a suitable hyperpolarized substrate capable of revealing multi-step metabolism in dynamic nuclear polarization experiments and providing information on the metabolism of fatty acids not currently achievable with other hyperpolarized substrates. Magn Reson Med 71:1663–1669, 2014. © 2013 Wiley Periodicals, Inc.
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Affiliation(s)
- Daniel R Ball
- Cardiac Metabolism Research Group, Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, UK
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Dodd MS, Ball V, Bray R, Ashrafian H, Watkins H, Clarke K, Tyler DJ. In vivo mouse cardiac hyperpolarized magnetic resonance spectroscopy. J Cardiovasc Magn Reson 2013; 15:19. [PMID: 23414451 PMCID: PMC3599631 DOI: 10.1186/1532-429x-15-19] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Accepted: 01/21/2013] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND Alterations in cardiac metabolism accompany many diseases of the heart. The advent of cardiac hyperpolarized magnetic resonance spectroscopy (MRS), via dynamic nuclear polarization (DNP), has enabled a greater understanding of the in vivo metabolic changes that occur as a consequence of myocardial infarction, hypertrophy and diabetes. However, all cardiac studies performed to date have focused on rats and larger animals, whereas more information could be gained through the study of transgenic mouse models of heart disease. Translation from the rat to the mouse is challenging, due in part to the reduced heart size (1/10(th)) and the increased heart rate (50%) in the mouse compared to the rat. METHODS AND RESULTS In this study, we have investigated the in vivo metabolism of [1-(13)C]pyruvate in the mouse heart. To demonstrate the sensitivity of the method to detect alterations in pyruvate dehydrogenase (PDH) flux, two well characterised methods of PDH modulation were performed; overnight fasting and infusion of sodium dichloroacetate (DCA). Fasting resulted in an 85% reduction in PDH flux, whilst DCA infusion increased PDH flux by 123%. A comparison of three commonly used control mouse strains was performed revealing significant metabolic differences between strains. CONCLUSIONS We have successfully demonstrated a hyperpolarized DNP protocol to investigate in vivo alterations within the diseased mouse heart. This technique offers a significant advantage over existing in vitro techniques as it reduces animal numbers and decreases biological variability. Thus [1-(13)C]pyruvate can be used to provide an in vivo cardiac metabolic profile of transgenic mice.
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Affiliation(s)
- Michael S Dodd
- Cardiac Metabolism Research Group, Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, UK
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Vicky Ball
- Cardiac Metabolism Research Group, Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, UK
| | - Rosalind Bray
- Cardiac Metabolism Research Group, Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, UK
| | - Houman Ashrafian
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Hugh Watkins
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Kieran Clarke
- Cardiac Metabolism Research Group, Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, UK
| | - Damian J Tyler
- Cardiac Metabolism Research Group, Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, UK
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Hassouna F, Kashyap S, Laachachi A, Ball V, Chapron D, Toniazzo V, Ruch D. Peculiar reduction of graphene oxide into graphene after diffusion in exponentially growing polyelectrolyte multilayers. J Colloid Interface Sci 2012; 377:489-96. [PMID: 22503661 DOI: 10.1016/j.jcis.2012.03.054] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2011] [Revised: 02/14/2012] [Accepted: 03/19/2012] [Indexed: 11/30/2022]
Abstract
In the present work, in situ reduction of graphene oxide (GO) into graphene was preformed, after diffusion in exponentially growing polyelectrolyte multilayers, using sodium citrate as the reducing agent. First, the graphene oxide was obtained by treating a commercial grade of Expanded Graphite (EG). Based on XRD and Raman spectroscopy results, a complete exfoliation of graphene nanopellets down to one layer was achieved during the oxidation process. Secondly, the diffusion of GO was carried out in an exponentially growing polyelectrolyte multilayer film made from poly(diallyldimethylammonium chloride) as the polycation and from poly(acrylic acid) as the polyanion. Electrical conductivity of the GO based films was measured during the reduction process as a function of time. The conductivity reached values of the order of 10(-4) S cm(-1), whereas the pristine polyelectrolyte multilayer was highly insulating (∼10(-8) S cm(-1)). The conductivity also reached a maximal value after about 24 h of reduction and decreased for longer reduction duration. Some tentative explanations for this peculiar finding will be given.
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Affiliation(s)
- F Hassouna
- Advanced Materials and Structures, Centre de Recherche Public Henri Tudor, 66 rue de Luxembourg, L-4002 Esch-sur-Alzette, Luxembourg
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Murphy HR, Steel SA, Roland JM, Morris D, Ball V, Campbell PJ, Temple RC. Obstetric and perinatal outcomes in pregnancies complicated by Type 1 and Type 2 diabetes: influences of glycaemic control, obesity and social disadvantage. Diabet Med 2011; 28:1060-7. [PMID: 21843303 PMCID: PMC3322333 DOI: 10.1111/j.1464-5491.2011.03333.x] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIMS To compare obstetric and perinatal outcomes in women with Type 1 and Type 2 diabetes and relate these to maternal risk factors. METHODS Prospective cohort study of 682 consecutive diabetic pregnancies in East Anglia during 2006-2009. Relationships between congenital malformation, perinatal mortality and perinatal morbidity (large for gestational age, preterm delivery, neonatal care) with maternal age, parity, ethnicity, glycaemic control, obesity and social disadvantage were examined using bivariable and multivariate models. RESULTS There were 408 (59.8%) Type 1 and 274 (40.2%) Type 2 diabetes pregnancies. Women with Type 2 diabetes were older (P < 0.001), heavier (P < 0.0001), more frequently multiparous (P < 0.001), more ethnically diverse (p < 0.0001) and more socially disadvantaged (P = 0.0004). Although women with Type 2 diabetes had shorter duration of diabetes (P < 0.0001) and better pre-conception glycaemic control [HbA(1c) 52 mmol/mol (6.9%) Type 2 diabetes vs. 63 mmol/l (7.9%) Type 1 diabetes; p < 0.0001), rates of congenital malformation and perinatal mortality were comparable. Women with Type 2 diabetes had fewer large-for-gestational-age infants (37.6 vs. 52.9%, P < 0.0008), fewer preterm deliveries (17.5 vs. 37.1%, P < 0.0001) and their offspring had fewer neonatal care admissions (29.8 vs. 43.2%, P = 0.001). Third trimester HbA(1c) (OR 1.35, 95% CI 1.09-1.67, P = 0.006) and social disadvantage (OR 0.80, 95% CI 0.67-0.98; P = 0.03) were risk factors for large for gestational age. CONCLUSIONS Despite increased age, parity, obesity and social disadvantage, women with Type 2 diabetes had better glycaemic control, fewer large-for-gestational-age infants, fewer preterm deliveries and fewer neonatal care admissions. Better tools are needed to improve glycaemic control and reduce the rates of large for gestational age, particularly in Type 1 diabetes.
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Affiliation(s)
- H R Murphy
- Metabolic Research Laboratories, Institute of Metabolic Science, University of Cambridge, Cambridge, UK.
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Girard CA, Wunderlich FT, Shimomura K, Collins S, Kaizik S, Proks P, Abdulkader F, Clark A, Ball V, Zubcevic L, Bentley L, Clark R, Church C, Hugill A, Galvanovskis J, Cox R, Rorsman P, Brüning JC, Ashcroft FM. Expression of an activating mutation in the gene encoding the KATP channel subunit Kir6.2 in mouse pancreatic beta cells recapitulates neonatal diabetes. J Clin Invest 2008; 119:80-90. [PMID: 19065048 PMCID: PMC2613450 DOI: 10.1172/jci35772] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2008] [Accepted: 10/29/2008] [Indexed: 12/25/2022] Open
Abstract
Neonatal diabetes is a rare monogenic form of diabetes that usually presents within the first six months of life. It is commonly caused by gain-of-function mutations in the genes encoding the Kir6.2 and SUR1 subunits of the plasmalemmal ATP-sensitive K+ (KATP) channel. To better understand this disease, we generated a mouse expressing a Kir6.2 mutation (V59M) that causes neonatal diabetes in humans and we used Cre-lox technology to express the mutation specifically in pancreatic beta cells. These beta-V59M mice developed severe diabetes soon after birth, and by 5 weeks of age, blood glucose levels were markedly increased and insulin was undetectable. Islets isolated from beta-V59M mice secreted substantially less insulin and showed a smaller increase in intracellular calcium in response to glucose. This was due to a reduced sensitivity of KATP channels in pancreatic beta cells to inhibition by ATP or glucose. In contrast, the sulfonylurea tolbutamide, a specific blocker of KATP channels, closed KATP channels, elevated intracellular calcium levels, and stimulated insulin release in beta-V59M beta cells, indicating that events downstream of KATP channel closure remained intact. Expression of the V59M Kir6.2 mutation in pancreatic beta cells alone is thus sufficient to recapitulate the neonatal diabetes observed in humans. beta-V59M islets also displayed a reduced percentage of beta cells, abnormal morphology, lower insulin content, and decreased expression of Kir6.2, SUR1, and insulin mRNA. All these changes are expected to contribute to the diabetes of beta-V59M mice. Their cause requires further investigation.
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Affiliation(s)
- Christophe A Girard
- Henry Wellcome Centre for Gene Function, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
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Abstract
AIM To compare the outcomes of Type 1 and Type 2 diabetic pregnancies and identify risk factors for poor outcome of Type 2 pregnancies METHODS The data from all (389 Type 1 and 146 Type 2) pre-gestational diabetic pregnancies from 10 UK hospitals were collected prospectively. RESULTS The Type 2 mothers were less likely to have documented pre-pregnancy counselling (28.7 vs. 40.5%; P<0.05) or be taking folic acid at conception (21.9 vs. 36.4%; P<0.001) than Type 1 mothers. The percentage of pregnancies having a serious adverse outcome was higher in Type 2 patients (16.4 vs. 6.4%; P=0.002). Congenital abnormalities (12.3% in Type 2 vs. 4.4% in Type 1; P=0.002) accounted for most of this difference. The HbA1c of the Type 2 patients was similar to that of the Type 1 with mean first trimester HbA1c of 7.22 and 7.35%, respectively (P=0.5). Treatment with oral hypoglycaemic agents [odds ratio (OR), 1.8; 95% confidence interval (CI), 1.0-3.3; P=0.04], body mass index (OR, 1.09; 95% CI, 1.01-1.18; P=0.02) and folic acid supplementation (OR, 0.3; 95% CI, 0.09-1.0; P=0.04) were all independently associated with congenital malformation. CONCLUSION Type 2 diabetic pregnancies are characterized by poor pre-pregnancy planning, inadequate folic acid supplementation and treatment with oral hypoglycaemic agents, all of which may contribute to the serious adverse outcomes affecting one in six Type 2 diabetic pregnancies. These remediable aspects of the pre-pregnancy care of women with Type 2 diabetes provide opportunities for improving the outcome towards that of women with Type 1 diabetes.
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Affiliation(s)
- J M Roland
- Peterborough and Stamford Hospitals NHS Foundation Trust, Peterborough, and Norwich University, UK.
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Hemmerlé J, Roucoules V, Fleith G, Nardin M, Ball V, Lavalle P, Marie P, Voegel JC, Schaaf P. Mechanically responsive films of variable hydrophobicity made of polyelectrolyte multilayers. Langmuir 2005; 21:10328-31. [PMID: 16262287 DOI: 10.1021/la052157g] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Mechanically responsive surfaces that allow to switch reversibly from a hydrophobic to a hydrophilic substrate are reported. The surfaces are constituted of polyelectrolyte multilayers deposited on modified charged silicone sheets. n bilayers of poly(allylamine)-Nafion (PAH-Naf) and m bilayers of poly(allylamine)-poly(acrylic acid) (PAH-PAA) composed the multilayers. A (PAH-Naf)(n) film possesses a water contact angle of around 105 degrees, whereas the contact angle of a (PAH-Naf)(4)-(PAH-PAA)(m) multilayer is around 50 degrees. When such a film with m < 5 and terminated by PAA is stretched out, its water contact angle increases up to around 100 degrees. Successive elongation/retraction cycles allow the water contact angle to alternate reversibly between 100 and 57 degrees indicating the reversible mechanical responsive nature of the film.
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Michel M, Izquierdo A, Decher G, Voegel JC, Schaaf P, Ball V. Layer by layer self-assembled polyelectrolyte multilayers with embedded phospholipid vesicles obtained by spraying: integrity of the vesicles. Langmuir 2005; 21:7854-9. [PMID: 16089392 DOI: 10.1021/la050497w] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
In a previous paper (Michel, M.; Vautier, D.; Voegel, J.-C.; Schaaf, P.; Ball, V. Langmuir 2004, 20, 4835), we showed that phospholipid vesicles can be incorporated into poly(glutamic-acid)/poly(allylamine) (PGA/PAH) multilayered polyelectrolyte films built by the alternated dipping of a surface in polyanion and polycation solutions. AFM imaging, quartz crystal microbalance, and ellipsometry suggested that the vesicles remain intact when adhering on the surface. In the present paper, we show that such films can also be realized by spraying both the polyelectrolyte solutions and the vesicles onto the surface. Using such vesicles filled with ferrocyanide ions, we prove by cyclic voltammetry that the sprayed vesicles remain intact when embedded in the multilayers. We show that multilayers containing two distinct layers of intact vesicles separated by several polyanion/polycation bilayers can also be constructed. Polyelectrolyte multilayers containing layers of phospholipid vesicles could act as reservoirs for drug or other biologically active molecules in controlled release bioactive coatings.
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Affiliation(s)
- M Michel
- Institut National de la Santé et de la Recherche Médicale, Unité 595, Faculté de Médecine, 11 rue Humann, 67085 Strasbourg Cedex, France
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Hübsch E, Fleith G, Fatisson J, Labbé P, Voegel JC, Schaaf P, Ball V. Multivalent ion/polyelectrolyte exchange processes in exponentially growing multilayers. Langmuir 2005; 21:3664-3669. [PMID: 15807618 DOI: 10.1021/la047258d] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We show, in this paper that multivalent ferrocyanide anions can penetrate into exponentially growing (PGA/PAH)n multilayer films whatever the nature of the last deposited layer. These ions are not able to diffuse out of the film when it is brought in contact with a pure buffer solution. However, the contact of this film with a poly(allylamine) (PAH) or a poly(L-glutamic acid) (PGA) solution leads to the release of ferrocyanide ions from the multilayer. It is shown that the release of ferrocyanide anions, when the film is in contact with a PGA solution, is due to the diffusion of the PGA chains into the film so that an exchange between ferrocyanide ions and PGA chains takes place inside the film. On the other hand, PAH chains do not diffuse into PGA/PAH multilayers. When the film is then brought in contact with a PAH solution, the PAH chains from the solution are expected to strongly interact with the ferrocyanide ions and thus induce a diffusion mechanism of the multivalent anions out of the film, the film/solution interface playing the role of a sink for these ions. This work thus shows that interactions between multivalent ions and exponentially growing films are much more complex than expected at first sight and that polyelectrolyte multilayers must be seen as dynamic entities in which diffusion and exchange processes can take place.
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Affiliation(s)
- E Hübsch
- Institut National de la Santé et de la Recherche Médicale, Unité 595, Faculté de Chirurgie Dentaire, 11 rue Humann, 67085 Strasbourg Cedex, France
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Porcel CH, Izquierdo A, Ball V, Decher G, Voegel JC, Schaaf P. Ultrathin coatings and (poly(glutamic acid)/polyallylamine) films deposited by continuous and simultaneous spraying. Langmuir 2005; 21:800-802. [PMID: 15641860 DOI: 10.1021/la047570n] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Affiliation(s)
- C H Porcel
- Unité INSERM U595, 2, Rue Humann, 67000, Strasbourg, France
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Drew C, Ball V, Robinson H, Clive Ellory J, Gibson JS. Oxygen sensitivity of red cell membrane transporters revisited. Bioelectrochemistry 2004; 62:153-8. [PMID: 15039019 DOI: 10.1016/j.bioelechem.2003.07.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2003] [Revised: 07/23/2003] [Accepted: 07/25/2003] [Indexed: 11/17/2022]
Abstract
In this paper, we provide an update on O2-dependent membrane transport in red cells. O2-sensitive membrane transport was compared in nucleated (chicken) and enucleated (human) red cells, to investigate effects on organic (glucose transporter [GLUT]) and inorganic (K(+)-Cl- cotransporter [KCC]/Na(+)-K(+)-2Cl- cotransporter [NKCC]) transporters, to study the response of so-called "housekeeping" transporters (Na+/K+ pump and anion exchanger [AE]) and, finally, to compare O2 sensitivity in normal human red cells with those from sickle cell patients. The Na+/K+ pump showed no change in activity between oxygenated and deoxygenated cells in any of the samples. KCC in normal human red cells had the greatest O2 sensitivity, being stimulated some 20-fold on oxygenation. It was more modestly stimulated by O2 in chicken red cells and HbS cells. By contrast, NKCC was stimulated by deoxygenation in all cases. GLUT showed little response to O2 tension, other than a small stimulation in deoxygenated chicken red cells. Finally, AE1 was stimulated by oxygenation in HbA cells, but this stimulation by O2 was absent in HbS cells and pink ghosts prepared from HbA cells. The significance of these findings is discussed.
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Affiliation(s)
- Clare Drew
- University Laboratory of Physiology, Parks Road, Oxford OX1 3PT, UK
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41
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Khan AI, Drew C, Ball SE, Ball V, Ellory JC, Gibson JS. Oxygen dependence of K(+)-Cl- cotransport in human red cell ghosts and sickle cells. Bioelectrochemistry 2004; 62:141-6. [PMID: 15039017 DOI: 10.1016/j.bioelechem.2003.07.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2003] [Revised: 07/23/2003] [Accepted: 07/25/2003] [Indexed: 11/26/2022]
Abstract
KCC activity in normal human red cells (containing haemoglobin A, HbA, and termed HbA cells) is O2-dependent, being active in oxygenated cells but inactive in deoxygenated ones. The mechanism for O2 dependence is unknown but a role for Hb has been suggested. In this paper, we address two main questions. First, do membrane ghosts prepared from HbA cells retain an O2-sensitive KCC activity? Second, how is the response of KCC to changes in O2 tension altered in sickle cell patients heterozygous for HbS and HbC? We found that substantial Cl(-)-dependent K+ influx, indicative of KCC activity, was present in both pink (5-10% normal Hb complement) and white (no measurable Hb) ghosts when equilibrated with air. KCC responded to deoxygenation in pink ghosts only (86 +/- 10% inhibition, mean+/-S.E.M., n = 3), whilst KCC activity in white ghosts remained high (23 +/- 8% inhibition). Results indicate that pink ghosts retain an O2-dependent KCC activity but that this is lost in white ghosts. Second, HbSC-containing red cells showed sickling (88 +/- 3%) when deoxygenated, together with activation of the deoxygenation-induced cation pathway (Psickle) and the Gardos channel. KCC activity, however, was elevated in oxygenated HbSC cells, but inhibited by deoxygenation. Thus Hb polymerisation and sickling could be dissociated from the abnormal response of KCC to deoxygenation observed in HbS-containing red cells. These preparations provide a useful system with which to study the components involved in O2-sensitive membrane transport and why it is perturbed in certain pathological conditions (such as sickle cell disease and oxidant toxicity).
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Affiliation(s)
- Asif I Khan
- University Laboratory of Physiology, Parks Road, Oxford OX1 3PT, UK
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Schwinté P, Ball V, Szalontai B, Haikel Y, Voegel JC, Schaaf P. Secondary structure of proteins adsorbed onto or embedded in polyelectrolyte multilayers. Biomacromolecules 2002; 3:1135-43. [PMID: 12425649 DOI: 10.1021/bm025547f] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The structural changes of bovine serum albumin (BSA) and hen egg white lysozyme (HEL) upon their adsorption onto the surface or their embedding into the interior of poly(allylamine hydrochloride)-(poly(styrenesulfonate) (PAH-PSS) multilayer architectures were investigated by attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. The presence of the polyelectrolytes seems, as previously observed for fibrinogen (J. Phys. Chem. B 2001, 105, 11906-11916), to prevent intermolecular interactions and, thus, protein aggregation at ambient temperature. The secondary structure of the proteins was somewhat altered upon adsorption onto the polyelectrolyte multilayers. The structural changes were larger when the charges of the multilayer outer layer and the protein were opposing. The adsorption of further polyelectrolyte layers onto protein-terminated architectures (i.e., embedding the proteins into a polyelectrolyte multilayer) did not cause considerable further changes in their secondary structures. The capacity of the polyelectrolyte architectures to delay the formation of intermolecular beta-sheets upon increasing temperatures was not uniform for the studied proteins. PSS in contact with HEL could largely prevent the heat-induced aggregation of HEL. In contrast, PAH had hardly any effect on the aggregation of BSA. The differences are explained on the basis of protein-polyelectrolyte interactions, affected mostly by the nature and the strength of the ionic interactions between the polyelectrolyte-protein contact surfaces.
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Affiliation(s)
- P Schwinté
- Institut National de la Santé et de la Recherche Médicale, Unité 424, UFR Odontologie, 11 rue Humann, 67085 Strasbourg Cedex, France
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Ball V, Winterhalter M, Schwinte P, Lavalle P, Voegel JC, Schaaf P. Complexation Mechanism of Bovine Serum Albumin and Poly(allylamine hydrochloride). J Phys Chem B 2002. [DOI: 10.1021/jp012522m] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- V. Ball
- Institut Charles Sadron, Centre National de la Recherche Scientifique, Unité Propre 22, 6 rue Boussingault, 67083 Strasbourg Cedex, France, Institut de Pharmacologie et de Biologie Structurale, Centre National de la Recherche Scientifique, Unité mixte de recherche 5089, 205 route de Narbonne, 31077 Toulouse, France, and Faculté de Médecine, Institut National de la Santé et de la Recherche Médicale, Unité 424, 11 rue Humann, 67085 Strasbourg Cedex, France
| | - M. Winterhalter
- Institut Charles Sadron, Centre National de la Recherche Scientifique, Unité Propre 22, 6 rue Boussingault, 67083 Strasbourg Cedex, France, Institut de Pharmacologie et de Biologie Structurale, Centre National de la Recherche Scientifique, Unité mixte de recherche 5089, 205 route de Narbonne, 31077 Toulouse, France, and Faculté de Médecine, Institut National de la Santé et de la Recherche Médicale, Unité 424, 11 rue Humann, 67085 Strasbourg Cedex, France
| | - P. Schwinte
- Institut Charles Sadron, Centre National de la Recherche Scientifique, Unité Propre 22, 6 rue Boussingault, 67083 Strasbourg Cedex, France, Institut de Pharmacologie et de Biologie Structurale, Centre National de la Recherche Scientifique, Unité mixte de recherche 5089, 205 route de Narbonne, 31077 Toulouse, France, and Faculté de Médecine, Institut National de la Santé et de la Recherche Médicale, Unité 424, 11 rue Humann, 67085 Strasbourg Cedex, France
| | - Ph. Lavalle
- Institut Charles Sadron, Centre National de la Recherche Scientifique, Unité Propre 22, 6 rue Boussingault, 67083 Strasbourg Cedex, France, Institut de Pharmacologie et de Biologie Structurale, Centre National de la Recherche Scientifique, Unité mixte de recherche 5089, 205 route de Narbonne, 31077 Toulouse, France, and Faculté de Médecine, Institut National de la Santé et de la Recherche Médicale, Unité 424, 11 rue Humann, 67085 Strasbourg Cedex, France
| | - J.-C. Voegel
- Institut Charles Sadron, Centre National de la Recherche Scientifique, Unité Propre 22, 6 rue Boussingault, 67083 Strasbourg Cedex, France, Institut de Pharmacologie et de Biologie Structurale, Centre National de la Recherche Scientifique, Unité mixte de recherche 5089, 205 route de Narbonne, 31077 Toulouse, France, and Faculté de Médecine, Institut National de la Santé et de la Recherche Médicale, Unité 424, 11 rue Humann, 67085 Strasbourg Cedex, France
| | - P. Schaaf
- Institut Charles Sadron, Centre National de la Recherche Scientifique, Unité Propre 22, 6 rue Boussingault, 67083 Strasbourg Cedex, France, Institut de Pharmacologie et de Biologie Structurale, Centre National de la Recherche Scientifique, Unité mixte de recherche 5089, 205 route de Narbonne, 31077 Toulouse, France, and Faculté de Médecine, Institut National de la Santé et de la Recherche Médicale, Unité 424, 11 rue Humann, 67085 Strasbourg Cedex, France
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Memmi L, Lazar A, Brioude A, Ball V, Coleman AW. Protein-calixarene interactions: complexation of Bovine Serum Albumin by sulfonatocalix[n]arenes. Chem Commun (Camb) 2001:2474-5. [PMID: 12240021 DOI: 10.1039/b109190p] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The complexation of Bovine Serum Albumin with sulfonatocalix[n]arenes has been demonstrated by means of electrospray mass spectrometry, dynamic light scattering and atomic force microscopy; with sulfonatocalix[4]arene one strong and two weaker binding sites are detected; the effects on the structure of thin films formed by surface deposition of BSA show that the sulfonatocalix[n]arenes act to reticulate the films and produce essentially planar systems.
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Affiliation(s)
- L Memmi
- Institut de Biologie et Chimie des Protéines, CNRS-UCBL1, UMR 5086, 7 passage du Vercors, Lyon, F69367, France
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Ball V, Winterhalter M, Perret F, Esposito G, Coleman AW. p-Sulfonatocalix[6]arene is an effective coacervator of poly(allylamine hydrochloride). Chem Commun (Camb) 2001:2276-7. [PMID: 12240148 DOI: 10.1039/b106361h] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
p-Sulfonatocalix[6]arene is shown to form insoluble complexes with poly(allylamine hydrochloride) when the charge balance between the negative calixarene sulfonate groups matches the positive charge carried by the polyelectrolyte, this makes this glycosylaminoglycan analog an interesting candidate for controlled release systems in the case of proteins encapsulated in mesoscopic complexes with polyelectrolytes.
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Affiliation(s)
- V Ball
- Institut Charles Sadron, Unité propre 22 CNRS, 6 rue Boussingault, 67083, Strasbourg, France.
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Rogniaux H, Sanglier S, Strupat K, Azza S, Roitel O, Ball V, Tritsch D, Branlant G, Van Dorsselaer A. Mass spectrometry as a novel approach to probe cooperativity in multimeric enzymatic systems. Anal Biochem 2001; 291:48-61. [PMID: 11262155 DOI: 10.1006/abio.2000.4975] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Investigating cooperativity in multimeric enzymes is of utmost interest to improve our understanding of the mechanism of enzymatic regulation. In the present article, we propose a novel approach based on mass spectrometry to probe cooperativity in the binding of a ligand to a multisubunit enzyme. This approach presents the selective advantage of giving a direct insight into all the subsequent ligation states that are formed in solution as the ligand is added to the enzyme. A quantitative interpretation of the electrospray ionization (ESI) mass spectra gives the relative abundance of all the distinct enzymatic species, which allows one to directly deduce the cooperativity of the system. The overall method is described for the addition of the oxidized cofactor nicotinamide adenine dinucleotide (NAD(+)) to a dimeric mutant of Bacillus stearothermophilus glyceraldehyde-3-phosphate dehydrogenase (GPDH). It is then applied to four tetrameric enzymes: sturgeon muscle GPDH, wild type and S48G mutant of GPDH from B. stearothermophilus, and alcohol dehydrogenase (ADH) from Bakers yeast. The results illustrate the possibilities offered by this new technique. First, mass spectrometry allows a control of the enzymes before the addition of NAD(+). Second, the cooperative behavior can be drawn from one single ESI mass spectrum, which makes the method highly attractive in terms of the amount of biological material required. Above all, the major benefit lies in the direct visualization of all the enzymatic species that are in equilibrium in solution. The direct measurement of cooperativity readily resolve the inconvenience of the classical approaches employed in this field, which all need to model the experimental data in order to get the cooperative behavior of the system.
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Affiliation(s)
- H Rogniaux
- Laboratoire de Spectrométrie de Masse Bio-Organique, CNRS UMR 7509, Université Louis Pasteur, 25 rue Becquerel, 67087 Strasbourg, France
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Lavalle P, Gergely C, Lustig A, Ball V. Critical analysis of the apoferritin adsorption at solid–liquid interfaces in the framework of a particular adsorption model. J Chem Phys 2000. [DOI: 10.1063/1.1314863] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Takes RP, Righi P, Meeuwis CA, Manni JJ, Knegt P, Marres HA, Spoelstra HA, de Boer MF, van der Mey AG, Bruaset I, Ball V, Weisberger E, Radpour S, Kruyt RH, Joosten FB, Laméris JS, van Oostayen JA, Kopecky K, Caldemeyer K, Henzen-Logmans SC, Wiersma-van Tilburg JM, Bosman FT, van Krieken JH, Hermans J, Baatenburg de Jong RJ. The value of ultrasound with ultrasound-guided fine-needle aspiration biopsy compared to computed tomography in the detection of regional metastases in the clinically negative neck. Int J Radiat Oncol Biol Phys 1998; 40:1027-32. [PMID: 9539556 DOI: 10.1016/s0360-3016(97)00953-x] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PURPOSE Head and neck oncologists have not reached consensus regarding the role of contemporary imaging techniques in the evaluation of the clinically negative neck in patients with head and neck squamous cell carcinoma (HNSCC). The purpose of the present study was to compare the accuracy of ultrasound with guided fine-needle aspiration biopsy (UGFNAB) and computed tomography (CT) in detecting lymph node metastasis in the clinically negative neck. METHODS AND MATERIALS Sixty-four neck sides of patients with HNSCC were examined preoperatively by ultrasound/UGFNAB and CT at one of five participating tertiary care medical centers. The findings were correlated with the results of histopathologic examination of the neck specimen. RESULTS Ultrasound with guided fine-needle aspiration biopsy was characterized by a sensitivity of 48%, specificity of 100%, and overall accuracy of 79%. Three cases had nondiagnostic aspirations using UGFNAB and were excluded. CT demonstrated a sensitivity of 54%, specificity of 92%, and overall accuracy of 77%. UGFNAB detected two additional metastases not visualized on CT, whereas CT detected no metastases not seen on UGFNAB. The results of UGFNAB were similar between the participating centers. CONCLUSIONS Approximately one half of the clinically occult nodal metastases in our patient group were identified by both CT and UGFNAB. Overall, UGFNAB and CT demonstrated comparable accuracy. The sensitivity of CT was slightly better than UGFNAB, but the latter remained characterized by a superior specificity. The results of CT and UGFNAB did not appear to be supplementary. The choice of imaging modality for staging of the clinically negative neck depends on tumor site, T-stage, and experience and preference of the head and neck oncologist. If CT is required for staging of the primary tumor, additional staging of the neck by UGFNAB does not provide significant additional value.
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Affiliation(s)
- R P Takes
- Department of Otolaryngology and Head and Neck Surgery, University Hospital Leiden, The Netherlands
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Affiliation(s)
- V Ball
- Department of Biophysical Chemistry, Biozentrum der Universität, Basel, Switzerland
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50
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Ball V, Ramsden JJ. Absence of Surface Exclusion in the First Stage of Lysozyme Adsorption Is Driven through Electrostatic Self-Assembly. J Phys Chem B 1997. [DOI: 10.1021/jp963812j] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- V. Ball
- Department of Biophysical Chemistry, Biozentrum of the University, Klingelbergstrasse 70, 4056 Basel, Switzerland
| | - J. J. Ramsden
- Department of Biophysical Chemistry, Biozentrum of the University, Klingelbergstrasse 70, 4056 Basel, Switzerland
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