1
|
Eykyn T, Elliott S, Kuchel P. Extended Bloch-McConnell equations for mechanistic analysis of hyperpolarized 13C magnetic resonance experiments on enzyme systems. MAGNETIC RESONANCE (GOTTINGEN, GERMANY) 2021; 2:421-446. [PMID: 37904769 PMCID: PMC10539799 DOI: 10.5194/mr-2-421-2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Accepted: 04/08/2021] [Indexed: 11/01/2023]
Abstract
We describe an approach to formulating the kinetic master equations of the time evolution of NMR signals in reacting (bio)chemical systems. Special focus is given to studies that employ signal enhancement (hyperpolarization) methods such as dissolution dynamic nuclear polarization (dDNP) and involving nuclear spin-bearing solutes that undergo reactions mediated by enzymes and membrane transport proteins. We extend the work given in a recent presentation on this topic (Kuchel and Shishmarev, 2020) to now include enzymes with two or more substrates and various enzyme reaction mechanisms as classified by Cleland, with particular reference to non-first-order processes. Using this approach, we can address some pressing questions in the field from a theoretical standpoint. For example, why does binding of a hyperpolarized substrate to an enzyme not cause an appreciable loss of the signal from the substrate or product? Why does the concentration of an unlabelled pool of substrate, for example 12 C lactate, cause an increase in the rate of exchange of the 13 C-labelled pool? To what extent is the equilibrium position of the reaction perturbed during administration of the substrate? The formalism gives a full mechanistic understanding of the time courses derived and is of relevance to ongoing clinical trials using these techniques.
Collapse
Affiliation(s)
- Thomas R. Eykyn
- School of Biomedical Engineering and Imaging Sciences, King's
College London, St Thomas' Hospital, London SE1 7EH, United Kingdom
| | - Stuart J. Elliott
- Centre de Résonance Magnétique Nucléaire à Très
Hauts Champs – FRE 2034 Université de Lyon / CNRS / Université
Claude Bernard Lyon 1 / ENS de Lyon, 5 Rue de la Doua, 69100 Villeurbanne,
France
- current address: Department of Chemistry, University of Liverpool,
Liverpool L69 7ZD, United Kingdom
| | - Philip W. Kuchel
- School of Life and Environmental Sciences, University of Sydney,
Sydney, NSW 2006, Australia
| |
Collapse
|
2
|
Traechtler J, Vishnevskiy V, Fuetterer M, Kozerke S. Joint image and field map estimation for multi-echo hyperpolarized 13 C metabolic imaging of the heart. Magn Reson Med 2021; 86:258-276. [PMID: 33660300 DOI: 10.1002/mrm.28710] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 01/13/2021] [Accepted: 01/14/2021] [Indexed: 12/21/2022]
Abstract
PURPOSE Image reconstruction of metabolic images from hyperpolarized 13 C multi-echo data acquisition is sensitive to susceptibility-induced phase offsets, which are particularly challenging in the heart. A model-based framework for joint estimation of metabolite images and field map from echo shift-encoded data is proposed. Using simulations, it is demonstrated that correction of signal spilling due to incorrect decomposition of metabolites and geometrical distortions over a wide range of off-resonance gradients is possible. In vivo feasibility is illustrated using hyperpolarized [1-13 C]pyruvate in the pig heart. METHODS The model-based reconstruction for multi-echo, multicoil data was implemented as a nonconvex minimization problem jointly optimizing for metabolic images and B0 . A comprehensive simulation framework for echo shift-encoded hyperpolarized [1-13 C]pyruvate imaging was developed and applied to assess reconstruction performance and distortion correction of the proposed method. In vivo data were obtained in four pigs using hyperpolarized [1-13 C]pyruvate on a clinical 3T MR system with a six-channel receiver coil. Dynamic images were acquired during suspended ventilation using cardiac-triggered multi-echo single-shot echo-planar imaging in short-axis orientation. RESULTS Simulations revealed that off-resonance gradients up to ±0.26 ppm/pixel can be corrected for with reduced signal spilling and geometrical distortions yielding an accuracy of ≥90% in terms of Dice similarity index. In vivo, improved geometrical consistency (10% Dice improvement) compared to image reconstruction without field map correction and with reference to anatomical data was achieved. CONCLUSION Joint image and field map estimation allows addressing off-resonance-induced geometrical distortions and metabolite spilling in hyperpolarized 13 C metabolic imaging of the heart.
Collapse
Affiliation(s)
- Julia Traechtler
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
| | - Valery Vishnevskiy
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
| | - Maximilian Fuetterer
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
| | - Sebastian Kozerke
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
| |
Collapse
|
3
|
Shaul D, Azar A, Sapir G, Uppala S, Nardi-Schreiber A, Gamliel A, Sosna J, Gomori JM, Katz-Brull R. Correlation between lactate dehydrogenase/pyruvate dehydrogenase activities ratio and tissue pH in the perfused mouse heart: A potential noninvasive indicator of cardiac pH provided by hyperpolarized magnetic resonance. NMR IN BIOMEDICINE 2021; 34:e4444. [PMID: 33258527 DOI: 10.1002/nbm.4444] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 10/05/2020] [Accepted: 10/24/2020] [Indexed: 06/12/2023]
Abstract
Cardiovascular diseases account for more than 30% of all deaths worldwide and many could be ameliorated with early diagnosis. Current cardiac imaging modalities can assess blood flow, heart anatomy and mechanical function. However, for early diagnosis and improved treatment, further functional biomarkers are needed. One such functional biomarker could be the myocardium pH. Although tissue pH is already determinable via MR techniques, and has been since the early 1990s, it remains elusive to use practically. The objective of this study was to explore the possibility to evaluate cardiac pH noninvasively, using in-cell enzymatic rates of hyperpolarized [1-13 C]pyruvate metabolism (ie, moles of product produced per unit time) determined directly in real time using magnetic resonance spectroscopy in a perfused mouse heart model. As a gold standard for tissue pH we used 31 P spectroscopy and the chemical shift of the inorganic phosphate (Pi) signal. The nonhomogenous pH distribution of the perfused heart was analyzed using a multi-parametric analysis of this signal, thus taking into account the heterogeneous nature of this characteristic. As opposed to the signal ratio of hyperpolarized [13 C]bicarbonate to [13 CO2 ], which has shown correlation to pH in other studies, we investigated here the ratio of two intracellular enzymatic rates: lactate dehydrogenase (LDH) and pyruvate dehydrogenase (PDH), by way of determining the production rates of [1-13 C]lactate and [13 C]bicarbonate, respectively. The enzyme activities determined here are intracellular, while the pH determined using the Pi signal may contain an extracellular component, which could not be ruled out. Nevertheless, we report a strong correlation between the tissue pH and the LDH/PDH activities ratio. This work may pave the way for using the LDH/PDH activities ratio as an indicator of cardiac intracellular pH in vivo, in an MRI examination.
Collapse
Affiliation(s)
- David Shaul
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - Assad Azar
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - Gal Sapir
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - Sivaranjan Uppala
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - Atara Nardi-Schreiber
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - Ayelet Gamliel
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - Jacob Sosna
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - J Moshe Gomori
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - Rachel Katz-Brull
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| |
Collapse
|
4
|
Mariager CØ, Hansen ESS, Bech SK, Eiskjaer H, Nielsen PF, Ringgaard S, Kimose HH, Laustsen C. Development of a human heart-sized perfusion system for metabolic imaging studies using hyperpolarized [1- 13 C]pyruvate MRI. Magn Reson Med 2020; 85:3510-3521. [PMID: 33368597 DOI: 10.1002/mrm.28639] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 11/09/2020] [Accepted: 11/19/2020] [Indexed: 11/09/2022]
Abstract
PURPOSE Increasing worldwide demand for cardiac transplantation has spurred new developments to increase the donor pool. Normothermic preservation of heart grafts for transplantation is an emerging strategy to improve the utilization of marginal grafts. Hyperpolarized MR using metabolic tracers such as [1-13 C]pyruvate, provide a novel means of investigating metabolic status without the use of ionizing radiation. We demonstrate the use of this methodology to examine ex vivo perfused porcine heart grafts. METHODS Hearts from three 40-kg Danish domestic pigs were harvested and subsequently perfused in Langendorff mode under normothermic conditions, using an MR-compatible perfusion system adapted to the heart. Proton MRI and hyperpolarized [1-13 C]pyruvate were used to investigate and quantify the functional and metabolic status of the grafts. RESULTS Hearts were perfused with whole blood for 120 min, using a dynamic contrast-enhanced perfusion experiment to verify successful myocardial perfusion. Hyperpolarized [1-13 C]pyruvate MRI was used to assess the metabolic state of the myocardium. Functional assessment was performed using CINE imaging and ventricular pressure data. High lactate and modest alanine levels were observed in the hyperpolarized experiment. The functional assessment produced reduced functional parameters. This suggests an altered functional and metabolic profile compared with corresponding in vivo values. CONCLUSION We investigated the metabolic and functional status of machine-perfused porcine hearts. Utilizing hyperpolarized methodology to acquire detailed myocardial metabolic information-in combination with already established MR methods for cardiac investigation-provides a powerful tool to aid the progress of donor heart preservation.
Collapse
Affiliation(s)
| | | | - Sabrina Kahina Bech
- Department of Clinical Medicine, MR Research Centre, Aarhus University, Aarhus, Denmark
| | - Hans Eiskjaer
- Department of Clinical Medicine, Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark
| | - Peter Fast Nielsen
- Department of Cardiothoracic Surgery, Aarhus University Hospital, Aarhus, Denmark
| | - Steffen Ringgaard
- Department of Clinical Medicine, MR Research Centre, Aarhus University, Aarhus, Denmark
| | - Hans-Henrik Kimose
- Department of Cardiothoracic Surgery, Aarhus University Hospital, Aarhus, Denmark
| | - Christoffer Laustsen
- Department of Clinical Medicine, MR Research Centre, Aarhus University, Aarhus, Denmark
| |
Collapse
|
5
|
Harris T, Uppala S, Lev-Cohain N, Adler-Levy Y, Shaul D, Nardi-Schreiber A, Sapir G, Azar A, Gamliel A, Sosna J, Gomori JM, Katz-Brull R. Hyperpolarized product selective saturating-excitations for determination of changes in metabolic reaction rates in real-time. NMR IN BIOMEDICINE 2020; 33:e4189. [PMID: 31793111 DOI: 10.1002/nbm.4189] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 08/04/2019] [Accepted: 08/16/2019] [Indexed: 06/10/2023]
Abstract
Investigation of hyperpolarized substrate metabolism has been showing utility in real-time determination of in-cell and in vivo enzymatic activities. Intracellular reaction rates may vary during the course of a measurement, even on the very short time scales of visibility on hyperpolarized MR, due to many factors such as the availability of the substrate and co-factors in the intracellular space. Despite this potential variation, the kinetic analysis of hyperpolarized signals typically assumes that the same rate constant (and in many cases, the same rate) applies throughout the course of the reaction as observed via the build-up and decay of the hyperpolarized signals. We demonstrate here an acquisition approach that can null the need for such an assumption and enable the detection of instantaneous changes in the rate of the reaction during an ex vivo hyperpolarized investigation, (i.e. in the course of the decay of one hyperpolarized substrate dose administered to a viable tissue sample ex vivo). This approach utilizes hyperpolarized product selective saturating-excitation pulses. Similar pulses have been previously utilized in vivo for spectroscopic imaging. However, we show here favorable consequences to kinetic rate determinations in the preparations used. We implement this acquisition strategy for studies on perfused tissue slices and develop a theory that explains why this particular approach enables the determination of changes in enzymatic rates that are monitored via the chemical conversions of hyperpolarized substrates. Real-time changes in intracellular reaction rates are demonstrated in perfused brain, liver, and xenograft breast cancer tissue slices and provide another potential differentiation parameter for tissue characterization.
Collapse
Affiliation(s)
- Talia Harris
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - Sivaranjan Uppala
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - Naama Lev-Cohain
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - Yael Adler-Levy
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - David Shaul
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - Atara Nardi-Schreiber
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - Gal Sapir
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - Assad Azar
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - Ayelet Gamliel
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - Jacob Sosna
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - J Moshe Gomori
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - Rachel Katz-Brull
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| |
Collapse
|
6
|
Mammoli D, Gordon J, Autry A, Larson PEZ, Li Y, Chen HY, Chung B, Shin P, Van Criekinge M, Carvajal L, Slater JB, Bok R, Crane J, Xu D, Chang S, Vigneron DB. Kinetic Modeling of Hyperpolarized Carbon-13 Pyruvate Metabolism in the Human Brain. IEEE TRANSACTIONS ON MEDICAL IMAGING 2020; 39:320-327. [PMID: 31283497 PMCID: PMC6939147 DOI: 10.1109/tmi.2019.2926437] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Kinetic modeling of the in vivo pyruvate-to-lactate conversion is crucial to investigating aberrant cancer metabolism that demonstrates Warburg effect modifications. Non-invasive detection of alterations to metabolic flux might offer prognostic value and improve the monitoring of response to treatment. In this clinical research project, hyperpolarized [1-13C] pyruvate was intravenously injected in a total of 10 brain tumor patients to measure its rate of conversion to lactate ( kPL ) and bicarbonate ( kPB ) via echo-planar imaging. Our aim was to investigate new methods to provide kPL and kPB maps with whole-brain coverage. The approach was data-driven and addressed two main issues: selecting the optimal model for fitting our data and determining an appropriate goodness-of-fit metric. The statistical analysis suggested that an input-less model had the best agreement with the data. It was also found that selecting voxels based on post-fitting error criteria provided improved precision and wider spatial coverage compared to using signal-to-noise cutoffs alone.
Collapse
|
7
|
Femnou AN, Giles A, Balaban RS. Intra-cardiac Side-Firing Light Catheter for Monitoring Cellular Metabolism using Transmural Absorbance Spectroscopy of Perfused Mammalian Hearts. J Vis Exp 2019. [PMID: 31132053 DOI: 10.3791/58992] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Absorbance spectroscopy of cardiac muscle provides non-destructive assessment of cytosolic and mitochondrial oxygenation via myoglobin and cytochrome absorbance respectively. In addition, numerous aspects of the mitochondrial metabolic status such as membrane potential and substrate entry can also be estimated. To perform cardiac wall transmission optical spectroscopy, a commercially available side-firing optical fiber catheter is placed in the left ventricle of the isolated perfused heart as a light source. Light passing through the heart wall is collected with an external optical fiber to perform optical spectroscopy of the heart in near real- time. The transmission approach avoids numerous surface scattering interference occurring in widely used reflection approaches. Changes in transmural absorbance spectra were deconvolved using a library of chromophore reference spectra, providing quantitative measures of all the known cardiac chromophores simultaneously. This spectral deconvolution approach eliminated intrinsic errors that may result from using common dual wavelength methods applied to overlapping absorbance spectra, as well as provided a quantitative evaluation of the goodness of fit. A custom program was designed for data acquisition and analysis, which permitted the investigator to monitor the metabolic state of the preparation during the experiment. These relatively simple additions to the standard heart perfusion system provide a unique insight into the metabolic state of the heart wall in addition to conventional measures of contraction, perfusion, and substrate/oxygen extraction.
Collapse
Affiliation(s)
- Armel N Femnou
- Laboratory of Cardiac Energetics, National Heart, Lung, and Blood Institute, National Institutes of Health; Department of Biomedical Engineering, The George Washington University
| | - Abigail Giles
- Laboratory of Cardiac Energetics, National Heart, Lung, and Blood Institute, National Institutes of Health
| | - Robert S Balaban
- Laboratory of Cardiac Energetics, National Heart, Lung, and Blood Institute, National Institutes of Health;
| |
Collapse
|
8
|
Funk AM, Wen X, Hever T, Maptue NR, Khemtong C, Sherry AD, Malloy CR. Effects of deuteration on transamination and oxidation of hyperpolarized 13C-Pyruvate in the isolated heart. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2019; 301:102-108. [PMID: 30861456 PMCID: PMC6666394 DOI: 10.1016/j.jmr.2019.03.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 03/01/2019] [Accepted: 03/03/2019] [Indexed: 06/04/2023]
Abstract
This study was designed to determine the effects of deuteration in pyruvate on exchange reactions in alanine aminotransferase (ALT), lactate dehydrogenase (LDH) and flux through pyruvate dehydrogenase (PDH). Although deuteration of a 13C enriched substrate is commonly used to increase the lifetime of a probe for hyperpolarization experiments, the potential impact of kinetic isotope effects on such substitutions has not been studied in detail. Metabolism of deuterated pyruvate was investigated in isolated rat hearts. Hearts were perfused with a 1:1 mixture of [U-13C3]pyruvate and [2-13C1]pyruvate or a 1:1 mixture of [U-13C3]pyruvate plus [2-13C1, U-2H3]pyruvate for 30 min before being freeze clamped. Another set of hearts received [2-13C1, U-2H3]pyruvate and was freeze-clamped at 3 min or 6 min. Tissue extracts were analyzed by 1H and 13C{1H} NMR spectroscopy. The chemical shift isotope effect of 2H was monitored in the 13C NMR spectra of the C2 resonance of lactate and alanine plus the C5 of glutamate. There was little kinetic isotope effect of 2H in pyruvate on flux through PDH, LDH or ALT as detected by the distribution of 13C, but the distribution of 2H differed markedly between alanine and lactate. At steady-state, alanine was a mixture of deuterated species, while lactate was largely perdeuterated. Consistent with results at steady-state, hearts freeze-clamped at 3 min or 6 min showed rapid removal of deuterium in alanine but not in lactate. Metabolism of hyperpolarized [1-13C1]pyruvate was compared to [1-13C1,U-2H3]pyruvate in isolated hearts. Consistent with the results from tissue extracts, there was little effect of deuteration on the kinetics of appearance of lactate, alanine or bicarbonate, but there was a small, time-dependent upfield chemical shift in the HP[1-13C1]alanine signal reflecting exchange of methyl deuterons with water protons. Together, these results demonstrate that (1) the kinetics of pyruvate metabolism in hearts detected by 13C NMR are not affected by replacement of the pyruvate methyl protons with deuterons and (2) that the loss of deuterium from the methyl position occurs rapidly during the conversion of pyruvate to alanine. The majority of the deuterium atoms are lost on the time-scale of a hyperpolarization experiment.
Collapse
Affiliation(s)
- Alexander M Funk
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Xiaodong Wen
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Thomas Hever
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Nesmine R Maptue
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Chalermchai Khemtong
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - A D Sherry
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, United States; Department of Radiology, University of Texas Southwestern Medical Center, Dallas, TX, United States; Department of Chemistry, University of Texas at Dallas, Richardson, TX, United States
| | - Craig R Malloy
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, United States; Department of Radiology, University of Texas Southwestern Medical Center, Dallas, TX, United States; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, United States; Veterans Affairs North Texas Healthcare System, Dallas, TX, United States.
| |
Collapse
|
9
|
Fuetterer M, Busch J, Traechtler J, Wespi P, Peereboom SM, Sauer M, Lipiski M, Fleischmann T, Cesarovic N, Stoeck CT, Kozerke S. Quantitative myocardial first-pass cardiovascular magnetic resonance perfusion imaging using hyperpolarized [1- 13C] pyruvate. J Cardiovasc Magn Reson 2018; 20:73. [PMID: 30415642 PMCID: PMC6231262 DOI: 10.1186/s12968-018-0495-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 10/09/2018] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND The feasibility of absolute myocardial blood flow quantification and suitability of hyperpolarized [1-13C] pyruvate as contrast agent for first-pass cardiovascular magnetic resonance (CMR) perfusion measurements are investigated with simulations and demonstrated in vivo in a swine model. METHODS A versatile simulation framework for hyperpolarized CMR subject to physical, physiological and technical constraints was developed and applied to investigate experimental conditions for accurate perfusion CMR with hyperpolarized [1-13C] pyruvate. Absolute and semi-quantitative perfusion indices were analyzed with respect to experimental parameter variations and different signal-to-noise ratio (SNR) levels. Absolute myocardial blood flow quantification was implemented with an iterative deconvolution approach based on Fermi functions. To demonstrate in vivo feasibility, velocity-selective excitation with an echo-planar imaging readout was used to acquire dynamic myocardial stress perfusion images in four healthy swine. Arterial input functions were extracted from an additional image slice with conventional excitation that was acquired within the same heartbeat. RESULTS Simulations suggest that obtainable SNR and B0 inhomogeneity in vivo are sufficient for the determination of absolute and semi-quantitative perfusion with ≤25% error. It is shown that for expected metabolic conversion rates, metabolic conversion of pyruvate can be neglected over the short duration of acquisition in first-pass perfusion CMR. In vivo measurements suggest that absolute myocardial blood flow quantification using hyperpolarized [1-13C] pyruvate is feasible with an intra-myocardial variability comparable to semi-quantitative perfusion indices. CONCLUSION The feasibility of quantitative hyperpolarized first-pass perfusion CMR using [1-13C] pyruvate has been investigated in simulations and demonstrated in swine. Using an approved and metabolically active compound is envisioned to increase the value of hyperpolarized perfusion CMR in patients.
Collapse
Affiliation(s)
- Maximilian Fuetterer
- Institute for Biomedical Engineering, University and ETH Zurich, Gloriastrasse, 35 8092 Zurich, Switzerland
| | - Julia Busch
- Institute for Biomedical Engineering, University and ETH Zurich, Gloriastrasse, 35 8092 Zurich, Switzerland
| | - Julia Traechtler
- Institute for Biomedical Engineering, University and ETH Zurich, Gloriastrasse, 35 8092 Zurich, Switzerland
| | - Patrick Wespi
- Institute for Biomedical Engineering, University and ETH Zurich, Gloriastrasse, 35 8092 Zurich, Switzerland
| | - Sophie M. Peereboom
- Institute for Biomedical Engineering, University and ETH Zurich, Gloriastrasse, 35 8092 Zurich, Switzerland
| | - Mareike Sauer
- Division of Surgical Research, University Hospital Zurich, Sternwartstrasse, 14 8091 Zurich, Switzerland
| | - Miriam Lipiski
- Division of Surgical Research, University Hospital Zurich, Sternwartstrasse, 14 8091 Zurich, Switzerland
| | - Thea Fleischmann
- Division of Surgical Research, University Hospital Zurich, Sternwartstrasse, 14 8091 Zurich, Switzerland
| | - Nikola Cesarovic
- Division of Surgical Research, University Hospital Zurich, Sternwartstrasse, 14 8091 Zurich, Switzerland
| | - Christian T. Stoeck
- Institute for Biomedical Engineering, University and ETH Zurich, Gloriastrasse, 35 8092 Zurich, Switzerland
| | - Sebastian Kozerke
- Institute for Biomedical Engineering, University and ETH Zurich, Gloriastrasse, 35 8092 Zurich, Switzerland
| |
Collapse
|
10
|
Larson PEZ, Chen HY, Gordon JW, Korn N, Maidens J, Arcak M, Tang S, Criekinge M, Carvajal L, Mammoli D, Bok R, Aggarwal R, Ferrone M, Slater JB, Nelson SJ, Kurhanewicz J, Vigneron DB. Investigation of analysis methods for hyperpolarized 13C-pyruvate metabolic MRI in prostate cancer patients. NMR IN BIOMEDICINE 2018. [PMID: 30230646 DOI: 10.1002/nbm.3997e3997] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
MRI using hyperpolarized (HP) carbon-13 pyruvate is being investigated in clinical trials to provide non-invasive measurements of metabolism for cancer and cardiac imaging. In this project, we applied HP [1-13 C]pyruvate dynamic MRI in prostate cancer to measure the conversion from pyruvate to lactate, which is expected to increase in aggressive cancers. The goal of this work was to develop and test analysis methods for improved quantification of this metabolic conversion. In this work, we compared specialized kinetic modeling methods to estimate the pyruvate-to-lactate conversion rate, kPL , as well as the lactate-to-pyruvate area-under-curve (AUC) ratio. The kinetic modeling included an "inputless" method requiring no assumptions regarding the input function, as well as a method incorporating bolus characteristics in the fitting. These were first evaluated with simulated data designed to match human prostate data, where we examined the expected sensitivity of metabolism quantification to variations in kPL , signal-to-noise ratio (SNR), bolus characteristics, relaxation rates, and B1 variability. They were then applied to 17 prostate cancer patient datasets. The simulations indicated that the inputless method with fixed relaxation rates provided high expected accuracy with no sensitivity to bolus characteristics. The AUC ratio showed an undesired strong sensitivity to bolus variations. Fitting the input function as well did not improve accuracy over the inputless method. In vivo results showed qualitatively accurate kPL maps with inputless fitting. The AUC ratio was sensitive to bolus delivery variations. Fitting with the input function showed high variability in parameter maps. Overall, we found the inputless kPL fitting method to be a simple, robust approach for quantification of metabolic conversion following HP [1-13 C]pyruvate injection in human prostate cancer studies. This study also provided initial ranges of HP [1-13 C]pyruvate parameters (SNR, kPL , bolus characteristics) in the human prostate.
Collapse
Affiliation(s)
- Peder E Z Larson
- Department of Radiology and Biomedical Imaging, University of California - San Francisco, San Francisco, California
- UC Berkeley-UCSF Graduate Program in Bioengineering, University of California, Berkeley and University of California, San Francisco, California
| | - Hsin-Yu Chen
- Department of Radiology and Biomedical Imaging, University of California - San Francisco, San Francisco, California
- UC Berkeley-UCSF Graduate Program in Bioengineering, University of California, Berkeley and University of California, San Francisco, California
| | - Jeremy W Gordon
- Department of Radiology and Biomedical Imaging, University of California - San Francisco, San Francisco, California
| | - Natalie Korn
- Department of Radiology and Biomedical Imaging, University of California - San Francisco, San Francisco, California
- UC Berkeley-UCSF Graduate Program in Bioengineering, University of California, Berkeley and University of California, San Francisco, California
| | - John Maidens
- Department of Electrical Engineering and Computer Sciences, University of California - Berkeley, Berkeley, California
| | - Murat Arcak
- Department of Electrical Engineering and Computer Sciences, University of California - Berkeley, Berkeley, California
| | - Shuyu Tang
- Department of Radiology and Biomedical Imaging, University of California - San Francisco, San Francisco, California
- UC Berkeley-UCSF Graduate Program in Bioengineering, University of California, Berkeley and University of California, San Francisco, California
| | - Mark Criekinge
- Department of Radiology and Biomedical Imaging, University of California - San Francisco, San Francisco, California
| | - Lucas Carvajal
- Department of Radiology and Biomedical Imaging, University of California - San Francisco, San Francisco, California
| | - Daniele Mammoli
- Department of Radiology and Biomedical Imaging, University of California - San Francisco, San Francisco, California
| | - Robert Bok
- Department of Radiology and Biomedical Imaging, University of California - San Francisco, San Francisco, California
| | - Rahul Aggarwal
- Department of Medicine, University of California - San Francisco, San Francisco, California
| | - Marcus Ferrone
- Department of Clinical Pharmacy, University of California - San Francisco, San Francisco, California
| | - James B Slater
- Department of Radiology and Biomedical Imaging, University of California - San Francisco, San Francisco, California
| | - Sarah J Nelson
- Department of Radiology and Biomedical Imaging, University of California - San Francisco, San Francisco, California
- UC Berkeley-UCSF Graduate Program in Bioengineering, University of California, Berkeley and University of California, San Francisco, California
| | - John Kurhanewicz
- Department of Radiology and Biomedical Imaging, University of California - San Francisco, San Francisco, California
- UC Berkeley-UCSF Graduate Program in Bioengineering, University of California, Berkeley and University of California, San Francisco, California
| | - Daniel B Vigneron
- Department of Radiology and Biomedical Imaging, University of California - San Francisco, San Francisco, California
- UC Berkeley-UCSF Graduate Program in Bioengineering, University of California, Berkeley and University of California, San Francisco, California
| |
Collapse
|
11
|
Larson PEZ, Chen HY, Gordon JW, Korn N, Maidens J, Arcak M, Tang S, Criekinge M, Carvajal L, Mammoli D, Bok R, Aggarwal R, Ferrone M, Slater JB, Nelson SJ, Kurhanewicz J, Vigneron DB. Investigation of analysis methods for hyperpolarized 13C-pyruvate metabolic MRI in prostate cancer patients. NMR IN BIOMEDICINE 2018; 31:e3997. [PMID: 30230646 PMCID: PMC6392436 DOI: 10.1002/nbm.3997] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 06/14/2018] [Accepted: 06/28/2018] [Indexed: 05/08/2023]
Abstract
MRI using hyperpolarized (HP) carbon-13 pyruvate is being investigated in clinical trials to provide non-invasive measurements of metabolism for cancer and cardiac imaging. In this project, we applied HP [1-13 C]pyruvate dynamic MRI in prostate cancer to measure the conversion from pyruvate to lactate, which is expected to increase in aggressive cancers. The goal of this work was to develop and test analysis methods for improved quantification of this metabolic conversion. In this work, we compared specialized kinetic modeling methods to estimate the pyruvate-to-lactate conversion rate, kPL , as well as the lactate-to-pyruvate area-under-curve (AUC) ratio. The kinetic modeling included an "inputless" method requiring no assumptions regarding the input function, as well as a method incorporating bolus characteristics in the fitting. These were first evaluated with simulated data designed to match human prostate data, where we examined the expected sensitivity of metabolism quantification to variations in kPL , signal-to-noise ratio (SNR), bolus characteristics, relaxation rates, and B1 variability. They were then applied to 17 prostate cancer patient datasets. The simulations indicated that the inputless method with fixed relaxation rates provided high expected accuracy with no sensitivity to bolus characteristics. The AUC ratio showed an undesired strong sensitivity to bolus variations. Fitting the input function as well did not improve accuracy over the inputless method. In vivo results showed qualitatively accurate kPL maps with inputless fitting. The AUC ratio was sensitive to bolus delivery variations. Fitting with the input function showed high variability in parameter maps. Overall, we found the inputless kPL fitting method to be a simple, robust approach for quantification of metabolic conversion following HP [1-13 C]pyruvate injection in human prostate cancer studies. This study also provided initial ranges of HP [1-13 C]pyruvate parameters (SNR, kPL , bolus characteristics) in the human prostate.
Collapse
Affiliation(s)
- Peder E. Z. Larson
- Department of Radiology and Biomedical Imaging, University of California – San Francisco, San Francisco, California
- UC Berkeley–UCSF Graduate Program in Bioengineering, University of California, Berkeley and University of California, San Francisco, California
| | - Hsin-Yu Chen
- Department of Radiology and Biomedical Imaging, University of California – San Francisco, San Francisco, California
- UC Berkeley–UCSF Graduate Program in Bioengineering, University of California, Berkeley and University of California, San Francisco, California
| | - Jeremy W. Gordon
- Department of Radiology and Biomedical Imaging, University of California – San Francisco, San Francisco, California
| | - Natalie Korn
- Department of Radiology and Biomedical Imaging, University of California – San Francisco, San Francisco, California
- UC Berkeley–UCSF Graduate Program in Bioengineering, University of California, Berkeley and University of California, San Francisco, California
| | - John Maidens
- Department of Electrical Engineering and Computer Sciences, University of California – Berkeley, Berkeley, California
| | - Murat Arcak
- Department of Electrical Engineering and Computer Sciences, University of California – Berkeley, Berkeley, California
| | - Shuyu Tang
- Department of Radiology and Biomedical Imaging, University of California – San Francisco, San Francisco, California
- UC Berkeley–UCSF Graduate Program in Bioengineering, University of California, Berkeley and University of California, San Francisco, California
| | - Mark Criekinge
- Department of Radiology and Biomedical Imaging, University of California – San Francisco, San Francisco, California
| | - Lucas Carvajal
- Department of Radiology and Biomedical Imaging, University of California – San Francisco, San Francisco, California
| | - Daniele Mammoli
- Department of Radiology and Biomedical Imaging, University of California – San Francisco, San Francisco, California
| | - Robert Bok
- Department of Radiology and Biomedical Imaging, University of California – San Francisco, San Francisco, California
| | - Rahul Aggarwal
- Department of Medicine, University of California – San Francisco, San Francisco, California
| | - Marcus Ferrone
- Department of Clinical Pharmacy, University of California – San Francisco, San Francisco, California
| | - James B. Slater
- Department of Radiology and Biomedical Imaging, University of California – San Francisco, San Francisco, California
| | - Sarah J. Nelson
- Department of Radiology and Biomedical Imaging, University of California – San Francisco, San Francisco, California
- UC Berkeley–UCSF Graduate Program in Bioengineering, University of California, Berkeley and University of California, San Francisco, California
| | - John Kurhanewicz
- Department of Radiology and Biomedical Imaging, University of California – San Francisco, San Francisco, California
- UC Berkeley–UCSF Graduate Program in Bioengineering, University of California, Berkeley and University of California, San Francisco, California
| | - Daniel B. Vigneron
- Department of Radiology and Biomedical Imaging, University of California – San Francisco, San Francisco, California
- UC Berkeley–UCSF Graduate Program in Bioengineering, University of California, Berkeley and University of California, San Francisco, California
| |
Collapse
|
12
|
Steinhauser J, Wespi P, Kwiatkowski G, Kozerke S. Assessing the influence of isoflurane anesthesia on cardiac metabolism using hyperpolarized [1- 13 C]pyruvate. NMR IN BIOMEDICINE 2018; 31. [PMID: 29206326 DOI: 10.1002/nbm.3856] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Revised: 09/15/2017] [Accepted: 10/02/2017] [Indexed: 05/07/2023]
Abstract
Isoflurane is a frequently used anesthetic in small-animal dissolution dynamic nuclear polarization-magnetic resonance imaging (DNP-MRI) studies. Although the literature suggests interactions with mitochondrial metabolism, the influence of the compound on cardiac metabolism has not been assessed systematically to date. In the present study, the impact of low versus high isoflurane concentration was examined in a crossover experiment in healthy rats. The results revealed that cardiac metabolism is modulated by isoflurane concentration, showing increased [1-13 C]lactate and reduced [13 C]bicarbonate production during high isoflurane relative to low isoflurane dose [average differences: +16% [1-13 C]lactate/total myocardial carbon, -22% [13 C]bicarbonate/total myocardial carbon; +51% [1-13 C]lactate/[13 C]bicarbonate]. These findings emphasize that reproducible anesthesia is important when studying cardiac metabolism. As the depth of anesthesia is difficult to control in an experimental animal setting, careful study design is required to exclude confounding factors.
Collapse
Affiliation(s)
- Jonas Steinhauser
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
| | - Patrick Wespi
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
| | - Grzegorz Kwiatkowski
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
| | - Sebastian Kozerke
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
| |
Collapse
|
13
|
Angelini A, Pi X, Xie L. Dioxygen and Metabolism; Dangerous Liaisons in Cardiac Function and Disease. Front Physiol 2017; 8:1044. [PMID: 29311974 PMCID: PMC5732914 DOI: 10.3389/fphys.2017.01044] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 11/29/2017] [Indexed: 12/19/2022] Open
Abstract
The heart must consume a significant amount of energy to sustain its contractile activity. Although the fuel demands are huge, the stock remains very low. Thus, in order to supply its daily needs, the heart must have amazing adaptive abilities, which are dependent on dioxygen availability. However, in myriad cardiovascular diseases, “fuel” depletion and hypoxia are common features, leading cardiomyocytes to favor low-dioxygen-consuming glycolysis rather than oxidation of fatty acids. This metabolic switch makes it challenging to distinguish causes from consequences in cardiac pathologies. Finally, despite the progress achieved in the past few decades, medical treatments have not improved substantially, either. In such a situation, it seems clear that much remains to be learned about cardiac diseases. Therefore, in this review, we will discuss how reconciling dioxygen availability and cardiac metabolic adaptations may contribute to develop full and innovative strategies from bench to bedside.
Collapse
Affiliation(s)
- Aude Angelini
- Department of Medicine-Athero and Lipo, Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX, United States
| | - Xinchun Pi
- Department of Medicine-Athero and Lipo, Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX, United States
| | - Liang Xie
- Department of Medicine-Athero and Lipo, Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX, United States
| |
Collapse
|