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Barnard AM, Willcocks RJ, Finanger EL, Daniels MJ, Triplett WT, Rooney WD, Lott DJ, Forbes SC, Wang DJ, Senesac CR, Harrington AT, Finkel RS, Russman BS, Byrne BJ, Tennekoon GI, Walter GA, Sweeney HL, Vandenborne K. Skeletal muscle magnetic resonance biomarkers correlate with function and sentinel events in Duchenne muscular dystrophy. PLoS One 2018; 13:e0194283. [PMID: 29554116 PMCID: PMC5858773 DOI: 10.1371/journal.pone.0194283] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 02/28/2018] [Indexed: 12/27/2022] Open
Abstract
OBJECTIVE To provide evidence for quantitative magnetic resonance (qMR) biomarkers in Duchenne muscular dystrophy by investigating the relationship between qMR measures of lower extremity muscle pathology and functional endpoints in a large ambulatory cohort using a multicenter study design. METHODS MR spectroscopy and quantitative imaging were implemented to measure intramuscular fat fraction and the transverse magnetization relaxation time constant (T2) in lower extremity muscles of 136 participants with Duchenne muscular dystrophy. Measures were collected at 554 visits over 48 months at one of three imaging sites. Fat fraction was measured in the soleus and vastus lateralis using MR spectroscopy, while T2 was assessed using MRI in eight lower extremity muscles. Ambulatory function was measured using the 10m walk/run, climb four stairs, supine to stand, and six minute walk tests. RESULTS Significant correlations were found between all qMR and functional measures. Vastus lateralis qMR measures correlated most strongly to functional endpoints (|ρ| = 0.68-0.78), although measures in other rapidly progressing muscles including the biceps femoris (|ρ| = 0.63-0.73) and peroneals (|ρ| = 0.59-0.72) also showed strong correlations. Quantitative MR biomarkers were excellent indicators of loss of functional ability and correlated with qualitative measures of function. A VL FF of 0.40 was an approximate lower threshold of muscle pathology associated with loss of ambulation. DISCUSSION Lower extremity qMR biomarkers have a robust relationship to clinically meaningful measures of ambulatory function in Duchenne muscular dystrophy. These results provide strong supporting evidence for qMR biomarkers and set the stage for their potential use as surrogate outcomes in clinical trials.
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Affiliation(s)
- Alison M. Barnard
- Department of Physical Therapy, University of Florida, Gainesville, FL, United States of America
| | - Rebecca J. Willcocks
- Department of Physical Therapy, University of Florida, Gainesville, FL, United States of America
| | - Erika L. Finanger
- Departments of Pediatrics and Neurology, Oregon Health & Science University, Portland, OR, United States of America
| | - Michael J. Daniels
- Department of Statistics, University of Florida, Gainesville, FL, United States of America
| | - William T. Triplett
- Department of Physical Therapy, University of Florida, Gainesville, FL, United States of America
| | - William D. Rooney
- Advanced Imaging Research Center, Oregon Health & Science University, Portland, OR, United States of America
| | - Donovan J. Lott
- Department of Physical Therapy, University of Florida, Gainesville, FL, United States of America
| | - Sean C. Forbes
- Department of Physical Therapy, University of Florida, Gainesville, FL, United States of America
| | - Dah-Jyuu Wang
- Department of Radiology, Division of Neurology, The Children’s Hospital of Philadelphia, Philadelphia, PA, United States of America
| | - Claudia R. Senesac
- Department of Physical Therapy, University of Florida, Gainesville, FL, United States of America
| | - Ann T. Harrington
- The Children’s Hospital of Philadelphia, Philadelphia, PA, United States of America
| | | | - Barry S. Russman
- Departments of Pediatrics and Neurology, Oregon Health & Science University, Portland, OR, United States of America
| | - Barry J. Byrne
- Department of Pediatrics and Molecular Genetics and Microbiology, Powell Gene Therapy Center, University of Florida, Gainesville, FL, United States of America
| | - Gihan I. Tennekoon
- The Children’s Hospital of Philadelphia, Philadelphia, PA, United States of America
| | - Glenn A. Walter
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, FL, United States of America
| | - H. Lee Sweeney
- Department of Pharmacology and Therapeutics, University of Florida, Gainesville, FL, United States of America
| | - Krista Vandenborne
- Department of Physical Therapy, University of Florida, Gainesville, FL, United States of America
- * E-mail:
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Fallon JR, McNally EM. Non-Glycanated Biglycan and LTBP4: Leveraging the extracellular matrix for Duchenne Muscular Dystrophy therapeutics. Matrix Biol 2018; 68-69:616-627. [PMID: 29481844 DOI: 10.1016/j.matbio.2018.02.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2018] [Revised: 02/18/2018] [Accepted: 02/19/2018] [Indexed: 12/15/2022]
Abstract
The extracellular matrix (ECM) plays key roles in normal and diseased skeletal and cardiac muscle. In healthy muscle the ECM is essential for transmitting contractile force, maintaining myofiber integrity and orchestrating cellular signaling. Duchenne Muscular Dystrophy (DMD) is caused by loss of dystrophin, a cytosolic protein that anchors a transmembrane complex and serves as a vital link between the actin cytoskeleton and the basal lamina. Loss of dystrophin leads to membrane fragility and impaired signaling, resulting in myofiber death and cycles of inflammation and regeneration. Fibrosis is also a cardinal feature of DMD. In this review, we will focus on two cases where understanding the normal function and regulation of ECM in muscle has led to the discovery of candidate therapeutics for DMD. Biglycan is a small leucine rich repeat ECM protein present as two glycoforms in muscle that have dramatically different functions. One widely expressed form is biglycan proteoglycan (PG) that bears two chondroitin sulfate GAG chains (typically chondroitin sulfate) and two N-linked carbohydrates. The second glycoform, referred to as 'NG' (non-glycanated) biglycan, lacks the GAG side chains. NG, but not PG biglycan recruits utrophin, an autosomal paralog of dystrophin, and an NOS-containing signaling complex to the muscle cell membrane. Recombinant NG biglycan can be systemically delivered to dystrophic mice where it upregulates utrophin at the membrane and improves muscle health and function. An optimized version of NG biglycan, 'TVN-102', is under development as a candidate therapeutic for DMD. A second matrix-embedded protein being evaluated for therapeutic potential is latent TGFβ binding protein 4 (LTBP4). Identified in a genomic screen for modifiers of muscular dystrophy, LTBP4 binds both TGFβ and myostatin. Genetic studies identified the hinge region of LTBP4 as linked to TGFβ release and contributing to the "hyper-TGFβ" signaling state that promotes fibrosis in muscular dystrophy. This hinge region can be stabilized by antibodies directed towards this domain. Stabilizing the hinge region of LTBP4 is expected to reduce latent TGFβ release and thus reduce fibrosis.
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Affiliation(s)
- Justin R Fallon
- Dept. of Neuroscience, Brown University, Providence, RI 02912, United States.
| | - Elizabeth M McNally
- Center for Genetic Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, United States
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103
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Leung DG, Wang X, Barker PB, Carrino JA, Wagner KR. Multivoxel proton magnetic resonance spectroscopy in facioscapulohumeral muscular dystrophy. Muscle Nerve 2018; 57:958-963. [PMID: 29266323 DOI: 10.1002/mus.26048] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 12/11/2017] [Accepted: 12/15/2017] [Indexed: 12/25/2022]
Abstract
INTRODUCTION Facioscapulohumeral muscular dystrophy (FSHD) is a hereditary disorder that causes progressive muscle wasting. This study evaluates the use of proton magnetic resonance spectroscopy (1 H MRS) as a biomarker of muscle strength and function in FSHD. METHODS Thirty-six individuals with FSHD and 15 healthy controls underwent multivoxel 1 H MRS of a cross-section of the mid-thigh. Concentrations of creatine, intramyocellular and extramyocellular lipids, and trimethylamine (TMA)-containing compounds in skeletal muscle were calculated. Metabolite concentrations for individuals with FSHD were compared with those of controls. The relationship between metabolite concentrations and muscle strength was also examined. RESULTS The TMA/creatine (Cr) ratio in individuals with FSHD was reduced compared with controls. The TMA/Cr ratio in the hamstrings also showed a moderate linear correlation with muscle strength. DISCUSSION 1 H MRS offers a potential method of detecting early muscle pathology in FSHD prior to the development of fat infiltration. Muscle Nerve 57: 958-963, 2018.
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Affiliation(s)
- Doris G Leung
- Center for Genetic Muscle Disorders, Hugo W. Moser Research Institute at Kennedy Krieger Institute, 716 North Broadway, Room 411, Baltimore, Maryland, 21205, USA.,Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Xin Wang
- Department of Radiation Oncology, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Peter B Barker
- Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - John A Carrino
- Department of Radiology and Imaging, Hospital for Special Surgery, New York, New York, USA
| | - Kathryn R Wagner
- Center for Genetic Muscle Disorders, Hugo W. Moser Research Institute at Kennedy Krieger Institute, 716 North Broadway, Room 411, Baltimore, Maryland, 21205, USA.,Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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104
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Willcocks RJ, Triplett WT, Lott DJ, Forbes SC, Batra A, Sweeney HL, Mendell JR, Vandenborne K, Walter GA. Leg muscle MRI in identical twin boys with duchenne muscular dystrophy. Muscle Nerve 2018; 58:10.1002/mus.26081. [PMID: 29365354 PMCID: PMC6057851 DOI: 10.1002/mus.26081] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 01/16/2018] [Accepted: 01/22/2018] [Indexed: 12/13/2022]
Affiliation(s)
- Rebecca J Willcocks
- University of Florida Department of Physical Therapy, Box 100154, UFHSC Gainesville, Florida, 32610-0154, USA
| | - William T Triplett
- University of Florida Department of Physical Therapy, Box 100154, UFHSC Gainesville, Florida, 32610-0154, USA
| | - Donovan J Lott
- University of Florida Department of Physical Therapy, Box 100154, UFHSC Gainesville, Florida, 32610-0154, USA
| | - Sean C Forbes
- University of Florida Department of Physical Therapy, Box 100154, UFHSC Gainesville, Florida, 32610-0154, USA
| | - Abhinandan Batra
- University of Florida Department of Physical Therapy, Box 100154, UFHSC Gainesville, Florida, 32610-0154, USA
| | - H Lee Sweeney
- Department of Pharmacology and Therapeutics, University of Florida, Gainesville, Florida, USA
| | | | - Krista Vandenborne
- University of Florida Department of Physical Therapy, Box 100154, UFHSC Gainesville, Florida, 32610-0154, USA
| | - Glenn A Walter
- Department of Physiology and Function Genomics, University of Florida, Gainesville, Florida, USA
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105
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Reyngoudt H, Turk S, Carlier PG. 1 H NMRS of carnosine combined with 31 P NMRS to better characterize skeletal muscle pH dysregulation in Duchenne muscular dystrophy. NMR IN BIOMEDICINE 2018; 31:e3839. [PMID: 29130550 DOI: 10.1002/nbm.3839] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 09/06/2017] [Accepted: 09/07/2017] [Indexed: 05/18/2023]
Abstract
In recent years, quantitative nuclear magnetic resonance imaging and spectroscopy (NMRI and NMRS) have been used more systematically as outcome measures in natural history and clinical trial studies for Duchenne muscular dystrophy (DMD). Whereas most of these studies have emphasized the evaluation of the fat fraction as an assessment for disease severity, less focus has been placed on metabolic indices measured by NMRS. 31 P NMRS in DMD reveals an alkaline inorganic phosphate (Pi ) pool, originating from either leaky dystrophic myocytes or an increased interstitial space. 1 H NMRS, exploiting the pH-sensitive proton resonances of carnosine, an intracellular dipeptide, was used to distinguish between these two hypotheses. NMR data were obtained in 23 patients with DMD and 14 healthy subjects on a 3-T clinical NMR system. Both 31 P and 1 H NMRS data were acquired at the level of the gastrocnemius medialis muscle. A multi-slice multi-echo imaging acquisition was performed for the determination of water T2 and fat fraction in the same region of interest. Whereas nearly all patients with DMD showed an elevated pH compared with healthy controls when using 31 P NMRS, 1 H NMRS-determined pH was not systematically increased. As expected, the carnosine-based intracellular pH was never found to be alkaline in the absence of a concurrent Pi -based pH elevation. In addition, abnormal intracellular pH, based on carnosine, was never associated with normal water T2 values. We conclude that, in one group of patients, both 1 H and 31 P NMRS showed an alkaline pH, originating from the intracellular compartment and reflecting ionic dysregulation in dystrophic myocytes. In the other patients with DMD, intracellular pH was normal, but an alkaline Pi pool was still present, suggesting an extracellular origin, probably revealing an expanded interstitial volume fraction, often associated with fibrotic changes. The data demonstrate that 1 H NMRS could serve as a biomarker to assess the normalization of intramyocytic pH and sarcolemmal permeability following therapy inducing dystrophin expression in patients with DMD.
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Affiliation(s)
- Harmen Reyngoudt
- NMR Laboratory, Institute of Myology, Paris, France
- CEA, DRF, IBFJ, MIRCen, Paris, France
| | - Suna Turk
- NMR Laboratory, Institute of Myology, Paris, France
- CEA, DRF, IBFJ, MIRCen, Paris, France
| | - Pierre G Carlier
- NMR Laboratory, Institute of Myology, Paris, France
- CEA, DRF, IBFJ, MIRCen, Paris, France
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106
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Goemans N, Mercuri E, Belousova E, Komaki H, Dubrovsky A, McDonald CM, Kraus JE, Lourbakos A, Lin Z, Campion G, Wang SX, Campbell C. A randomized placebo-controlled phase 3 trial of an antisense oligonucleotide, drisapersen, in Duchenne muscular dystrophy. Neuromuscul Disord 2017; 28:4-15. [PMID: 29203355 DOI: 10.1016/j.nmd.2017.10.004] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 09/23/2017] [Accepted: 10/17/2017] [Indexed: 01/16/2023]
Abstract
This 48-week, randomized, placebo-controlled phase 3 study (DMD114044; NCT01254019) evaluated efficacy and safety of subcutaneous drisapersen 6 mg/kg/week in 186 ambulant boys aged ≥5 years, with Duchenne muscular dystrophy (DMD) resulting from an exon 51 skipping amenable mutation. Drisapersen was generally well tolerated, with injection-site reactions and renal events as most commonly reported adverse events. A nonsignificant treatment difference (P = 0.415) in the change from baseline in six-minute walk distance (6MWD; primary efficacy endpoint) of 10.3 meters in favor of drisapersen was observed at week 48. Key secondary efficacy endpoints (North Star Ambulatory Assessment, 4-stair climb ascent velocity, and 10-meter walk/run velocity) gave consistent findings. Lack of statistical significance was thought to be largely due to greater data variability and subgroup heterogeneity. The increased standard deviation alone, due to less stringent inclusion/exclusion criteria, reduced the statistical power from pre-specified 90% to actual 53%. Therefore, a post-hoc analysis was performed in 80 subjects with a baseline 6MWD 300-400 meters and ability to rise from floor. A statistically significant improvement in 6MWD of 35.4 meters (P = 0.039) in favor of drisapersen was observed in this subpopulation. Results suggest that drisapersen could have benefit in a less impaired population of DMD subjects.
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Affiliation(s)
- Nathalie Goemans
- Department of Pediatrics and Child Neurology, University Hospitals Leuven, Leuven, Belgium.
| | | | - Elena Belousova
- Research and Clinical Institute of Pediatrics, Pirogov Russian National Research Medical University, Moscow, Russia
| | - Hirofumi Komaki
- Department of Child Neurology, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Alberto Dubrovsky
- Fundacion Cenit, Instituto de Neurociencias, Fundación Favaloro, Buenos Aires, Argentina
| | - Craig M McDonald
- School of Medicine, University of California, Davis, Sacramento, CA, USA
| | - John E Kraus
- GlaxoSmithKline, Research Triangle Park, NC, USA
| | | | | | | | | | - Craig Campbell
- Paediatric Neurology, Schulich School of Medicine, Western University, London, Canada
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107
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Muscle MRI and functional outcome measures in Becker muscular dystrophy. Sci Rep 2017; 7:16060. [PMID: 29167533 PMCID: PMC5700122 DOI: 10.1038/s41598-017-16170-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 11/06/2017] [Indexed: 11/08/2022] Open
Abstract
Becker muscular dystrophy (BMD) is a neuromuscular disorder allelic to Duchenne muscular dystrophy (DMD), caused by in-frame mutations in the dystrophin gene, and characterized by a clinical progression that is both milder and more heterogeneous than DMD. Muscle magnetic resonance imaging (MRI) has been proposed as biomarker of disease progression in dystrophinopathies. Correlation with clinically meaningful outcome measures such as North Star Ambulatory Assessment (NSAA) and 6 minute walk test (6MWT) is paramount for biomarker qualification. In this study, 51 molecularly confirmed BMD patients (aged 7-69 years) underwent muscle MRI and were evaluated with functional measures (NSAA and 6MWT) at the time of the MRI, and subsequently after one year. We confirmed a pattern of fatty substitution involving mainly the hip extensors and most thigh muscles. Severity of muscle fatty substitution was significantly correlated with specific DMD mutations: in particular, patients with an isolated deletion of exon 48, or deletions bordering exon 51, showed milder involvement. Fat infiltration scores correlated with baseline functional measures, and predicted changes after 1 year. We conclude that in BMD, skeletal muscle MRI not only strongly correlates with motor function, but also helps in predicting functional deterioration within a 12-month time frame.
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108
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Timed function tests, motor function measure, and quantitative thigh muscle MRI in ambulant children with Duchenne muscular dystrophy: A cross-sectional analysis. Neuromuscul Disord 2017; 28:16-23. [PMID: 29174526 DOI: 10.1016/j.nmd.2017.10.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 09/08/2017] [Accepted: 10/17/2017] [Indexed: 12/25/2022]
Abstract
The development of new therapeutic agents for the treatment of Duchenne muscular dystrophy has put a focus on defining outcome measures most sensitive to capture treatment effects. This cross-sectional analysis investigates the relation between validated clinical assessments such as the 6-minute walk test, motor function measure and quantitative muscle MRI of thigh muscles in ambulant Duchenne muscular dystrophy patients, aged 6.5 to 10.8 years (mean 8.2, SD 1.1). Quantitative muscle MRI included the mean fat fraction using a 2-point Dixon technique, and transverse relaxation time (T2) measurements. All clinical assessments were highly significantly inter-correlated with p < 0.001. The strongest correlation with the motor function measure and its D1-subscore was shown by the 6-minute walk test. Clinical assessments showed no correlation with age. Importantly, quantitative muscle MRI values significantly correlated with all clinical assessments with the extensors showing the strongest correlation. In contrast to the clinical assessments, quantitative muscle MRI values were highly significantly correlated with age. In conclusion, the motor function measure and timed function tests measure disease severity in a highly comparable fashion and all tests correlated with quantitative muscle MRI values quantifying fatty muscle degeneration.
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109
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Fledrich R, Mannil M, Leha A, Ehbrecht C, Solari A, Pelayo-Negro AL, Berciano J, Schlotter-Weigel B, Schnizer TJ, Prukop T, Garcia-Angarita N, Czesnik D, Haberlová J, Mazanec R, Paulus W, Beissbarth T, Walter MC, CMT-TRIAAL, Hogrel JY, Dubourg O, Schenone A, Baets J, De Jonghe P, Shy ME, Horvath R, Pareyson D, Seeman P, Young P, Sereda MW. Biomarkers predict outcome in Charcot-Marie-Tooth disease 1A. J Neurol Neurosurg Psychiatry 2017; 88:941-952. [PMID: 28860329 PMCID: PMC8265963 DOI: 10.1136/jnnp-2017-315721] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 04/05/2017] [Accepted: 05/02/2017] [Indexed: 11/03/2022]
Abstract
BACKGROUND Charcot-Marie-Tooth disease type 1A (CMT1A) is the most common inherited neuropathy, a debilitating disease without known cure. Among patients with CMT1A, disease manifestation, progression and severity are strikingly variable, which poses major challenges for the development of new therapies. Hence, there is a strong need for sensitive outcome measures such as disease and progression biomarkers, which would add powerful tools to monitor therapeutic effects in CMT1A. METHODS We established a pan-European and American consortium comprising nine clinical centres including 311 patients with CMT1A in total. From all patients, the CMT neuropathy score and secondary outcome measures were obtained and a skin biopsy collected. In order to assess and validate disease severity and progression biomarkers, we performed qPCR on a set of 16 animal model-derived potential biomarkers in skin biopsy mRNA extracts. RESULTS In 266 patients with CMT1A, a cluster of eight cutaneous transcripts differentiates disease severity with a sensitivity and specificity of 90% and 76.1%, respectively. In an additional cohort of 45 patients with CMT1A, from whom a second skin biopsy was taken after 2-3 years, the cutaneous mRNA expression of GSTT2, CTSA, PPARG, CDA, ENPP1 and NRG1-Iis changing over time and correlates with disease progression. CONCLUSIONS In summary, we provide evidence that cutaneous transcripts in patients with CMT1A serve as disease severity and progression biomarkers and, if implemented into clinical trials, they could markedly accelerate the development of a therapy for CMT1A.
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Affiliation(s)
- Robert Fledrich
- Department of Clinical Neurophysiology, University Medical Center Göttingen (UMG), Göttingen, Germany
- Research Group “Molecular and Translational Neurology”, Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Manoj Mannil
- Department of Clinical Neurophysiology, University Medical Center Göttingen (UMG), Göttingen, Germany
- Research Group “Molecular and Translational Neurology”, Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Andreas Leha
- Department of Medical Statistics, University Medical Center Göttingen (UMG), Göttingen, Germany
| | - Caroline Ehbrecht
- Research Group “Molecular and Translational Neurology”, Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Alessandra Solari
- Unit of Neuroepidemiology, IRCCS Foundation, C. Besta Neurological Institute, Milan, Italy
| | - Ana L. Pelayo-Negro
- Service of Neurology, University Hospital “Marqués de Valdecilla (IDIVAL)”, University of Cantabria, and “Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED)”, Santander, Spain
| | - José Berciano
- Service of Neurology, University Hospital “Marqués de Valdecilla (IDIVAL)”, University of Cantabria, and “Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED)”, Santander, Spain
| | - Beate Schlotter-Weigel
- Friedrich-Baur-Institut, Department of Neurology, Ludwig-Maximilians-University of Munich, Germany
| | - Tuuli J. Schnizer
- Department of Clinical Neurophysiology, University Medical Center Göttingen (UMG), Göttingen, Germany
| | - Thomas Prukop
- Department of Clinical Neurophysiology, University Medical Center Göttingen (UMG), Göttingen, Germany
- Research Group “Molecular and Translational Neurology”, Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
- Institute of Clinical Pharmacology, University Medical Center Göttingen (UMG), Göttingen, Germany
| | - Natalia Garcia-Angarita
- Friedrich-Baur-Institut, Department of Neurology, Ludwig-Maximilians-University of Munich, Germany
| | - Dirk Czesnik
- Department of Clinical Neurophysiology, University Medical Center Göttingen (UMG), Göttingen, Germany
| | - Jana Haberlová
- Department of Child Neurology, Charles University in Prague, 2nd Medical School, and University Hospital Motol Prague, Czech Republic
| | - Radim Mazanec
- Department of Child Neurology, Charles University in Prague, 2nd Medical School, and University Hospital Motol Prague, Czech Republic
| | - Walter Paulus
- Department of Clinical Neurophysiology, University Medical Center Göttingen (UMG), Göttingen, Germany
| | - Tim Beissbarth
- Department of Medical Statistics, University Medical Center Göttingen (UMG), Göttingen, Germany
| | - Maggie C. Walter
- Friedrich-Baur-Institut, Department of Neurology, Ludwig-Maximilians-University of Munich, Germany
| | - CMT-TRIAAL
- CMT-TRIAAL (all participants in the appendix of this manuscript)
| | | | - Odile Dubourg
- Institute of Myology, GH Pitié-Salpêtrière, Paris, France
| | - Angelo Schenone
- Department of Neurology, Ophthalmology and Genetics, University of Genoa, Genoa, Italy
| | - Jonathan Baets
- Neurogenetics Group, Department of Molecular Genetics, VIB, Antwerp, Belgium
- Institute Born-Bunge, University of Antwerp, Antwerpen, Belgium
- Department of Neurology, Antwerp University Hospital, Antwerpen, Belgium
| | - Peter De Jonghe
- Neurogenetics Group, Department of Molecular Genetics, VIB, Antwerp, Belgium
- Institute Born-Bunge, University of Antwerp, Antwerpen, Belgium
- Department of Neurology, Antwerp University Hospital, Antwerpen, Belgium
| | - Michael E. Shy
- Department of Neurology, Carver College of Medicine, University of Iowa, Iowa City, USA
| | - Rita Horvath
- John Walton Muscular Dystrophy Research Centre, Institute of Genetic Medicine, Newcastle University, UK
| | - Davide Pareyson
- Unit of Neurological Rare Diseases of Adulthood, Department of Clinical Neurosciences, IRCCS Foundation, C. Besta Neurological Institute, Milan, Italy
| | - Pavel Seeman
- Department of Child Neurology, Charles University in Prague, 2nd Medical School, and University Hospital Motol Prague, Czech Republic
| | - Peter Young
- Department of Sleep Medicine and Neuromuscular Disorders, University Hospital Münster, Germany
| | - Michael W. Sereda
- Department of Clinical Neurophysiology, University Medical Center Göttingen (UMG), Göttingen, Germany
- Research Group “Molecular and Translational Neurology”, Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
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Wilson K, Faelan C, Patterson-Kane JC, Rudmann DG, Moore SA, Frank D, Charleston J, Tinsley J, Young GD, Milici AJ. Duchenne and Becker Muscular Dystrophies: A Review of Animal Models, Clinical End Points, and Biomarker Quantification. Toxicol Pathol 2017; 45:961-976. [PMID: 28974147 DOI: 10.1177/0192623317734823] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) are neuromuscular disorders that primarily affect boys due to an X-linked mutation in the DMD gene, resulting in reduced to near absence of dystrophin or expression of truncated forms of dystrophin. Some newer therapeutic interventions aim to increase sarcolemmal dystrophin expression, and accurate dystrophin quantification is critical for demonstrating pharmacodynamic relationships in preclinical studies and clinical trials. Current challenges with measuring dystrophin include the variation in protein expression within individual muscle fibers and across whole muscle samples, the presence of preexisting dystrophin-positive revertant fibers, and trace amounts of residual dystrophin. Immunofluorescence quantification of dystrophin can overcome many of these challenges, but manual quantification of protein expression may be complicated by variations in the collection of images, reproducible scoring of fluorescent intensity, and bias introduced by manual scoring of typically only a few high-power fields. This review highlights the pathology of DMD and BMD, discusses animal models of DMD and BMD, and describes dystrophin biomarker quantitation in DMD and BMD, with several image analysis approaches, including a new automated method that evaluates protein expression of individual muscle fibers.
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Affiliation(s)
- Kristin Wilson
- 1 Flagship Biosciences, Inc., Westminster, Colorado, USA
| | - Crystal Faelan
- 1 Flagship Biosciences, Inc., Westminster, Colorado, USA
| | | | | | - Steven A Moore
- 2 Department of Pathology, Carver College of Medicine, The University of Iowa, Iowa City, Iowa, USA
| | - Diane Frank
- 3 Sarepta Therapeutics, Inc., Cambridge, Massachusetts, USA
| | - Jay Charleston
- 3 Sarepta Therapeutics, Inc., Cambridge, Massachusetts, USA
| | - Jon Tinsley
- 4 Summit Therapeutics, Abingdon, United Kingdom
| | - G David Young
- 1 Flagship Biosciences, Inc., Westminster, Colorado, USA
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McDonald CM, Campbell C, Torricelli RE, Finkel RS, Flanigan KM, Goemans N, Heydemann P, Kaminska A, Kirschner J, Muntoni F, Osorio AN, Schara U, Sejersen T, Shieh PB, Sweeney HL, Topaloglu H, Tulinius M, Vilchez JJ, Voit T, Wong B, Elfring G, Kroger H, Luo X, McIntosh J, Ong T, Riebling P, Souza M, Spiegel RJ, Peltz SW, Mercuri E. Ataluren in patients with nonsense mutation Duchenne muscular dystrophy (ACT DMD): a multicentre, randomised, double-blind, placebo-controlled, phase 3 trial. Lancet 2017; 390:1489-1498. [PMID: 28728956 DOI: 10.1016/s0140-6736(17)31611-2] [Citation(s) in RCA: 301] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 05/09/2017] [Accepted: 05/11/2017] [Indexed: 02/07/2023]
Abstract
BACKGROUND Duchenne muscular dystrophy (DMD) is a severe, progressive, and rare neuromuscular, X-linked recessive disease. Dystrophin deficiency is the underlying cause of disease; therefore, mutation-specific therapies aimed at restoring dystrophin protein production are being explored. We aimed to assess the efficacy and safety of ataluren in ambulatory boys with nonsense mutation DMD. METHODS We did this multicentre, randomised, double-blind, placebo-controlled, phase 3 trial at 54 sites in 18 countries located in North America, Europe, the Asia-Pacific region, and Latin America. Boys aged 7-16 years with nonsense mutation DMD and a baseline 6-minute walk distance (6MWD) of 150 m or more and 80% or less of the predicted normal value for age and height were randomly assigned (1:1), via permuted block randomisation (block size of four) using an interactive voice-response or web-response system, to receive ataluren orally three times daily (40 mg/kg per day) or matching placebo. Randomisation was stratified by age (<9 years vs ≥9 years), duration of previous corticosteroid use (6 months to <12 months vs ≥12 months), and baseline 6MWD (<350 m vs ≥350 m). Patients, parents and caregivers, investigational site personnel, PTC Therapeutics employees, and all other study personnel were masked to group allocation until after database lock. The primary endpoint was change in 6MWD from baseline to week 48. We additionally did a prespecified subgroup analysis of the primary endpoint, based on baseline 6MWD, which is reflective of anticipated rates of disease progression over 1 year. The primary analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT01826487. FINDINGS Between March 26, 2013, and Aug 26, 2014, we randomly assigned 230 patients to receive ataluren (n=115) or placebo (n=115); 228 patients comprised the intention-to-treat population. The least-squares mean change in 6MWD from baseline to week 48 was -47·7 m (SE 9·3) for ataluren-treated patients and -60·7 m (9·3) for placebo-treated patients (difference 13·0 m [SE 10·4], 95% CI -7·4 to 33·4; p=0·213). The least-squares mean change for ataluren versus placebo in the prespecified subgroups was -7·7 m (SE 24·1, 95% CI -54·9 to 39·5; p=0·749) in the group with a 6MWD of less than 300 m, 42·9 m (15·9, 11·8-74·0; p=0·007) in the group with a 6MWD of 300 m or more to less than 400 m, and -9·5 m (17·2, -43·2 to 24·2; p=0·580) in the group with a 6MWD of 400 m or more. Ataluren was generally well tolerated and most treatment-emergent adverse events were mild to moderate in severity. Eight (3%) patients (n=4 per group) reported serious adverse events; all except one event in the placebo group (abnormal hepatic function deemed possibly related to treatment) were deemed unrelated to treatment. INTERPRETATION Change in 6MWD did not differ significantly between patients in the ataluren group and those in the placebo group, neither in the intention-to-treat population nor in the prespecified subgroups with a baseline 6MWD of less than 300 m or 400 m or more. However, we recorded a significant effect of ataluren in the prespecified subgroup of patients with a baseline 6MWD of 300 m or more to less than 400 m. Baseline 6MWD values within this range were associated with a more predictable rate of decline over 1 year; this finding has implications for the design of future DMD trials with the 6-minute walk test as the endpoint. FUNDING PTC Therapeutics.
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Affiliation(s)
- Craig M McDonald
- University of California Davis School of Medicine, Davis, Sacramento, CA, USA.
| | - Craig Campbell
- Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
| | | | - Richard S Finkel
- Children's Hospital of Philadelphia, Philadelphia, PA, USA; Nemours Children's Hospital, Orlando, FL, USA
| | | | | | | | | | - Janbernd Kirschner
- Medical Center-University of Freiburg, University of Freiberg, Freiberg, Germany
| | - Francesco Muntoni
- University College London Great Ormond Street Institute of Child Health, London, UK
| | | | - Ulrike Schara
- University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Thomas Sejersen
- Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden
| | | | | | | | - Már Tulinius
- Gothenburg University, Queen Silvia Children's Hospital, Gothenburg, Sweden
| | - Juan J Vilchez
- Hospital Universitario y Politécnico La Fe, CIBERER, Valencia, Spain
| | - Thomas Voit
- University College London Great Ormond Street Institute of Child Health, London, UK; National Institute for Health Research Great Ormond Street Hospital University College London Biomedical Research Centre, London, UK
| | - Brenda Wong
- Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | | | | | | | | | - Tuyen Ong
- PTC Therapeutics, South Plainfield, NJ, USA
| | | | | | | | | | - Eugenio Mercuri
- Department of Pediatric Neurology, Catholic University, Rome, Italy
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113
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Hooijmans MT, Doorenweerd N, Baligand C, Verschuuren JJGM, Ronen I, Niks EH, Webb AG, Kan HE. Spatially localized phosphorous metabolism of skeletal muscle in Duchenne muscular dystrophy patients: 24-month follow-up. PLoS One 2017; 12:e0182086. [PMID: 28763477 PMCID: PMC5538641 DOI: 10.1371/journal.pone.0182086] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 07/12/2017] [Indexed: 12/29/2022] Open
Abstract
Objectives To assess the changes in phosphodiester (PDE)-levels, detected by 31P magnetic resonance spectroscopy (MRS), over 24-months to determine the potential of PDE as marker for muscle tissue changes in Duchenne Muscular Dystrophy (DMD) patients. Methods Spatially resolved phosphorous datasets were acquired in the right lower leg of 18 DMD patients (range: 5–15.4 years) and 12 age-matched healthy controls (range: 5–14 years) at three time-points (baseline, 12-months, and 24-months) using a 7T MR-System (Philips Achieva). 3-point Dixon images were acquired at 3T (Philips Ingenia) to determine muscle fat fraction. Analyses were done for six muscles that represent different stages of muscle wasting. Differences between groups and time-points were assessed with non-parametric tests with correction for multiple comparisons. Coefficient of variance (CV) were determined for PDE in four healthy adult volunteers in high and low signal-to-noise ratio (SNR) datasets. Results PDE-levels were significantly higher (two-fold) in DMD patients compared to controls in all analyzed muscles at almost every time point and did not change over the study period. Fat fraction was significantly elevated in all muscles at all time points compared to healthy controls, and increased significantly over time, except in the tibialis posterior muscle. The mean within subject CV for PDE-levels was 4.3% in datasets with high SNR (>10:1) and 5.7% in datasets with low SNR. Discussion and conclusion The stable two-fold increase in PDE-levels found in DMD patients in muscles with different levels of muscle wasting over 2-year time, including DMD patients as young as 5.5 years-old, suggests that PDE-levels may increase very rapidly early in the disease process and remain elevated thereafter. The low CV values in high and low SNR datasets show that PDE-levels can be accurately and reproducibly quantified in all conditions. Our data confirms the great potential of PDE as a marker for muscle tissue changes in DMD patients.
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Affiliation(s)
- M. T. Hooijmans
- Dept of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands
- * E-mail:
| | - N. Doorenweerd
- Dept of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands
- John Walton Muscular Dystrophy Research Centre, Newcastle University, Newcastle Upon Tyne, United Kingdom
| | - C. Baligand
- Dept of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands
| | | | - I. Ronen
- Dept of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands
| | - E. H. Niks
- Dept of Neurology, Leiden University Medical Center, Leiden, The Netherlands
| | - A. G. Webb
- Dept of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands
| | - H. E. Kan
- Dept of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands
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Burakiewicz J, Sinclair CDJ, Fischer D, Walter GA, Kan HE, Hollingsworth KG. Quantifying fat replacement of muscle by quantitative MRI in muscular dystrophy. J Neurol 2017; 264:2053-2067. [PMID: 28669118 PMCID: PMC5617883 DOI: 10.1007/s00415-017-8547-3] [Citation(s) in RCA: 130] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 06/12/2017] [Accepted: 06/13/2017] [Indexed: 12/15/2022]
Abstract
The muscular dystrophies are rare orphan diseases, characterized by progressive muscle weakness: the most common and well known is Duchenne muscular dystrophy which affects young boys and progresses quickly during childhood. However, over 70 distinct variants have been identified to date, with different rates of progression, implications for morbidity, mortality, and quality of life. There are presently no curative therapies for these diseases, but a range of potential therapies are presently reaching the stage of multi-centre, multi-national first-in-man clinical trials. There is a need for sensitive, objective end-points to assess the efficacy of the proposed therapies. Present clinical measurements are often too dependent on patient effort or motivation, and lack sensitivity to small changes, or are invasive. Quantitative MRI to measure the fat replacement of skeletal muscle by either chemical shift imaging methods (Dixon or IDEAL) or spectroscopy has been demonstrated to provide such a sensitive, objective end-point in a number of studies. This review considers the importance of the outcome measures, discusses the considerations required to make robust measurements and appropriate quality assurance measures, and draws together the existing literature for cross-sectional and longitudinal cohort studies using these methods in muscular dystrophy.
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Affiliation(s)
- Jedrzej Burakiewicz
- Department of Radiology, C. J. Gorter Center for High Field MRI, Leiden University Medical Centre, Leiden, The Netherlands
| | - Christopher D J Sinclair
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, London, UK.,Neuroradiological Academic Unit, UCL Institute of Neurology, London, UK
| | - Dirk Fischer
- Division of Neuropaediatrics, University of Basel Children's Hospital, Spitalstrasse 33, Postfach, Basel, 4031, Switzerland.,Department of Neurology, University of Basel Hospital, Petersgraben 4, Basel, 4031, Switzerland
| | - Glenn A Walter
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, FL, 32610, USA
| | - Hermien E Kan
- Department of Radiology, C. J. Gorter Center for High Field MRI, Leiden University Medical Centre, Leiden, The Netherlands
| | - Kieren G Hollingsworth
- Newcastle Magnetic Resonance Centre, Institute of Cellular Medicine, Newcastle University, Newcastle-upon-Tyne, UK.
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Heller KN, Mendell JT, Mendell JR, Rodino-Klapac LR. MicroRNA-29 overexpression by adeno-associated virus suppresses fibrosis and restores muscle function in combination with micro-dystrophin. JCI Insight 2017; 2:93309. [PMID: 28469083 DOI: 10.1172/jci.insight.93309] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 04/04/2017] [Indexed: 12/30/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is caused by dystrophin deficiency resulting in progressive muscle weakness and fibrotic scarring. Muscle fibrosis impairs blood flow, hampering muscle repair and regeneration. Irrespective of the success of gene restoration, functional improvement is limited without reducing fibrosis. The levels of miR-29c, a known regulator of collagen, are reduced in DMD. Our goal is to develop translational, antifibrotic therapy by overexpressing miR-29c. We injected the gastrocnemius muscle with either self-complementary AAV.CMV.miR-29c or single-stranded AAV.MCK.micro-dystrophin alone or in combination in the mdx/utrn+/- mouse, a DMD mouse model. Treatment of 3-month-old mdx/utrn+/- mice with AAV.miR-29c showed a reduction in collagen and increased absolute and specific force compared with untreated animals, but neither parameter reached WT levels. Combinatorial gene delivery in 3-month-old mdx/utrn+/- mice further decreased fibrosis, and showed a reduction of transcript levels for Col1A, Col3A, fibronectin, and Tgfb1. In addition, absolute and specific force was normalized and equivalent to WT. However, protection against eccentric contraction fell short of WT levels at this time point. When this same mouse model was treated with miR-29c/micro-dystrophin combinatorial therapy at 1 month of age, there was complete normalization of specific and absolute force and protection against eccentric contraction-induced injury was comparable to WT. These findings highlight the potential for miR-29c as an important addition to the armamentarium for translational gene therapy, especially when used in combination with micro-dystrophin in DMD.
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Affiliation(s)
- Kristin N Heller
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA.,Department of Pediatrics and Neurology, The Ohio State University, Columbus, Ohio, USA
| | - Joshua T Mendell
- Department of Molecular Biology.,Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Jerry R Mendell
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA.,Department of Pediatrics and Neurology, The Ohio State University, Columbus, Ohio, USA
| | - Louise R Rodino-Klapac
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA.,Department of Pediatrics and Neurology, The Ohio State University, Columbus, Ohio, USA
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Rutkove SB, Kapur K, Zaidman CM, Wu JS, Pasternak A, Madabusi L, Yim S, Pacheck A, Szelag H, Harrington T, Darras BT. Electrical impedance myography for assessment of Duchenne muscular dystrophy. Ann Neurol 2017; 81:622-632. [PMID: 28076894 DOI: 10.1002/ana.24874] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2016] [Revised: 12/24/2016] [Accepted: 12/26/2016] [Indexed: 12/14/2022]
Abstract
OBJECTIVE Sensitive, objective, and easily applied methods for evaluating disease progression and response to therapy are needed for clinical trials in Duchenne muscular dystrophy (DMD). In this study, we evaluated whether electrical impedance myography (EIM) could serve this purpose. METHODS In this nonblinded study, 36 boys with DMD and 29 age-similar healthy boys underwent multifrequency EIM measurements for up to 2 years on 6 muscles unilaterally along with functional assessments. A linear mixed-effects model with random intercept and slope terms was used for the analysis of multifrequency EIM values and functional measures. Seven DMD boys were initiated on corticosteroids; these data were analyzed using a piecewise linear mixed-effects model. RESULTS In boys > 7.0 years old, a significant difference in the slope of EIM phase ratio trajectories in the upper extremity was observed by 6 months of -0.074/month, p = 0.023, 95% confidence interval (CI) = -0.013, -0.14; at 2 years, this difference was -0.048/month, p < 0.0001, 95% CI = -0.028, -0.068. In boys ≤ 7.0 years old, differences appeared at 6 months in gastrocnemius (EIM phase slope = -0.83 °/kHz/mo, p = 0.007, 95% CI = -0.26, -1.40). EIM outcomes showed significant differences earlier than functional tests. Initiation of corticosteroids significantly improved the slope of EIM phase ratio (0.057/mo, p = 0.00019, 95% CI = 0.028, 0.086) and EIM phase slope (0.14 °/kHz/mo, p = 0.013, 95% CI = 0.028, 0.25), consistent with corticosteroids' known clinical benefit. INTERPRETATION EIM detects deterioration in muscles of both younger and older boys by 6 months; it also identifies the therapeutic effect of corticosteroid initiation. Because EIM is rapid to apply, painless, and requires minimal operator training, the technique deserves to be further evaluated as a biomarker in DMD clinical therapeutic trials. Ann Neurol 2017;81:622-632.
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Affiliation(s)
- Seward B Rutkove
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
| | - Kush Kapur
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Craig M Zaidman
- Department of Neurology, Washington University in St Louis, St Louis, MO
| | - Jim S Wu
- Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
| | - Amy Pasternak
- Department of Physical Therapy Services and Occupational Therapy Services, Boston Children's Hospital, Boston, MA
| | - Lavanya Madabusi
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Sung Yim
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
| | - Adam Pacheck
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
| | - Heather Szelag
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Tim Harrington
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Basil T Darras
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA
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Zaidman CM, Wu JS, Kapur K, Pasternak A, Madabusi L, Yim S, Pacheck A, Szelag H, Harrington T, Darras BT, Rutkove SB. Quantitative muscle ultrasound detects disease progression in Duchenne muscular dystrophy. Ann Neurol 2017; 81:633-640. [PMID: 28241384 DOI: 10.1002/ana.24904] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2016] [Revised: 02/21/2017] [Accepted: 02/22/2017] [Indexed: 01/19/2023]
Abstract
OBJECTIVE We assessed changes in quantitative muscle ultrasound data in boys with Duchenne muscular dystrophy (DMD) and healthy controls to determine whether ultrasound can serve as a biomarker of disease progression. Two approaches were used: gray scale level (GSL), measured from the ultrasound image, and quantitative backscatter analysis (QBA), measured directly from the received echoes. METHODS GSL and QBA were obtained from 6 unilateral arm/leg muscles in 36 boys with DMD and 28 healthy boys (age = 2-14 years) for up to 2 years. We used a linear mixed effects model with random intercept and slope terms to compare trajectories of GSL, QBA, and functional assessments. We analyzed separately a subset of boys who initiated corticosteroids. RESULTS Compared to healthy boys, increasing GSL in DMD boys >7.0 years old was first identified at 6 months (eg, anterior forearm slope difference of 1.16 arbitrary units/mo, p = 0.004, 95% confidence interval [CI] = 0.38-1.94); in boys ≤ 7 years old, differences in GSL first appeared at 12 months (0.82 arbitrary units/mo, p = 0.04, 95% CI = 0.075-1.565, in rectus femoris). QBA performed similarly to GSL (eg, DMD boys > 7 years old: 0.41dB/mo, p = 0.01, 95% CI = 0.096-0.72, in anterior forearm at 6 months). Ultrasound identified differences earlier than functional measures including 6-minute walk and supine-to-stand tests. However, neither QBA nor GSL showed an effect of corticosteroid initiation. INTERPRETATION QBA performs similarly to GSL, and both appear more sensitive than functional assessments for detecting muscle deterioration in DMD. Additional studies will be required to determine whether quantitative muscle ultrasound can detect therapeutic efficacy. Ann Neurol 2017;81:633-640.
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Affiliation(s)
- Craig M Zaidman
- Department of Neurology, Washington University in St Louis, St Louis, MO
| | - Jim S Wu
- Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
| | - Kush Kapur
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Amy Pasternak
- Department of Physical Therapy Services and Occupational Therapy Services, Boston Children's Hospital, Boston, MA
| | - Lavanya Madabusi
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Sung Yim
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA
| | - Adam Pacheck
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA
| | - Heather Szelag
- Department of Neurology, Washington University in St Louis, St Louis, MO
| | - Tim Harrington
- Department of Neurology, Washington University in St Louis, St Louis, MO
| | - Basil T Darras
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Seward B Rutkove
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA
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Non-uniform muscle fat replacement along the proximodistal axis in Duchenne muscular dystrophy. Neuromuscul Disord 2017; 27:458-464. [PMID: 28302391 DOI: 10.1016/j.nmd.2017.02.009] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 02/14/2017] [Accepted: 02/15/2017] [Indexed: 12/25/2022]
Abstract
The progressive replacement of muscle tissue by fat in Duchenne muscular dystrophy (DMD) has been studied using quantitative MRI between, but not within, individual muscles. We studied fat replacement along the proximodistal muscle axis using the Dixon technique on a 3T MR scanner in 22 DMD patients and 12 healthy controls. Mean fat fractions per muscle per slice for seven lower and upper leg muscles were compared between and within groups assuming a parabolic distribution. Average fat fraction for a small central slice stack and a large coverage slice stack were compared to the value when the stack was shifted one slice (15 mm) up or down. Higher fat fractions were observed in distal and proximal muscle segments compared to the muscle belly in all muscles of the DMD subjects (p <0.001). A shift of 15 mm resulted in a difference in mean fat fraction which was on average 1-2% ranging up to 12% (p <0.01). The muscle end regions are exposed to higher mechanical strain, which points towards mechanical disruption of the sarcolemma as one of the key factors in the pathophysiology. Overall, this non-uniformity in fat replacement needs to be taken into account to prevent sample bias when applying quantitative MRI as biomarker in clinical trials for DMD.
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119
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Larkindale J, Abresch R, Aviles E, Bronson A, Chin J, Furlong P, Gordish-Dressman H, Habeeb-Louks E, Henricson E, Kroger H, Lynn C, Lynn S, Martin D, Nuckolls G, Rooney W, Romero K, Sweeney L, Vandenborne K, Walter G, Wolff J, Wong B, McDonald CM, Duchenne Regulatory Science Consortium Imaging-Dmd Consortium And The Cinrg Investigators MOT. Duchenne Regulatory Science Consortium Meeting on Disease Progression Modeling for Duchenne Muscular Dystrophy. PLOS CURRENTS 2017; 9. [PMID: 28228973 PMCID: PMC5300692 DOI: 10.1371/currents.md.83071bbd728982f2f1073f4950e03586] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
INTRODUCTION The Duchenne Regulatory Science Consortium (D-RSC) was established to develop tools to accelerate drug development for DMD. The resulting tools are anticipated to meet validity requirements outlined by qualification/endorsement pathways at both the U.S. Food and Drug Administration (FDA) and European Medicines Administration (EMA), and will be made available to the drug development community. The initial goals of the consortium include the development of a disease progression model, with the goal of creating a model that would be used to forecast changes in clinically meaningful endpoints, which would inform clinical trial protocol development and data analysis. Methods: In April of 2016 the consortium and other experts met to formulate plans for the development of the model. Conclusions: Here we report the results of the meeting, and discussion as to the form of the model that we plan to move forward to develop, after input from the regulatory authorities.
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Affiliation(s)
| | - Richard Abresch
- Department of Physical Medicine and Rehabilitation, University of California, Sacramento, California, USA
| | - Enrique Aviles
- Duchenne Regulatory Science Consortium, Critical Path Institute, Tucson, Arizona, USA
| | - Abby Bronson
- Parent Project Muscular Dystrophy, Hackensack, New Jersey, USA
| | - Janice Chin
- Pfizer, Rare Disease Research Unit, Cambridge, Massachusetts, USA
| | - Pat Furlong
- Parent Project Muscular Dystrophy, Hackensack, New Jersey, USA
| | | | | | - Erik Henricson
- University of California Davis Medical Center, Department of Physical Medicine and Rehabilitation, Sacramento, California, USA
| | - Hans Kroger
- PTC Therapeutics, South Plainfield, New Jersey, USA
| | - Charles Lynn
- Duchenne Regulatory Science Consortium, Critical Path Institute, Tucson, Arizona, USA
| | - Stephen Lynn
- Stephen Lynn, Newcastle University, Newcastle upon Tyne, UK
| | - Dana Martin
- Sarepta Therapeutics, Medical Affairs & Patient Advocacy, Cambridge, Massachusetts, USA
| | - Glen Nuckolls
- NINDS, National Institute of Health, Washington DC, USA
| | - William Rooney
- Advanced Imaging Research Center, Oregon Health & Science University, Portland, Oregon, USA
| | - Klaus Romero
- Duchenne Regulatory Science Consortium, Critical Path Institute, Tucson, Arizona, USA
| | - Lee Sweeney
- Department of Pharmacology and Therapeutics, University of Florida, Gainesville, Florida, USA
| | - Krista Vandenborne
- Department of Physical Therapy, University of Florida, Gainesville, Florida, USA
| | - Glenn Walter
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, Florida, USA
| | - Jodi Wolff
- Santhera Pharmaceuticals, Tucson, Arizona, USA
| | - Brenda Wong
- Division of Pediatric Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Craig M McDonald
- Department of Physical Medicine and Rehabilitation, University of California, Sacramento, California, USA
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Hooijmans MT, Niks EH, Burakiewicz J, Verschuuren JJGM, Webb AG, Kan HE. Elevated phosphodiester and T 2 levels can be measured in the absence of fat infiltration in Duchenne muscular dystrophy patients. NMR IN BIOMEDICINE 2017; 30:e3667. [PMID: 27859827 DOI: 10.1002/nbm.3667] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 10/10/2016] [Accepted: 10/10/2016] [Indexed: 05/27/2023]
Abstract
Quantitative MRI and MRS are increasingly important as non-invasive outcome measures in therapy development for Duchenne muscular dystrophy (DMD). Many studies have focussed on individual measures such as fat fraction and metabolite levels in relation to age and functionality, but much less attention has been given to how these indices relate to each other. Here, we assessed spatially resolved metabolic changes in leg muscles of DMD patients, and classified muscles according to the degree of fat replacement compared with healthy controls. Quantitative MRI (three-point Dixon and multi-spin echo without fat suppression and a tri-exponential fit) and 2D-CSI 31 P MRS scans were obtained from 18 DMD patients and 12 healthy controls using a 3 T and a 7 T MR scanner. Metabolite levels, T2 values and fat fraction were individually assessed for five lower leg muscles. In muscles with extensive fat replacement, phosphodiester over adenosine triphosphate (PDE/ATP), inorganic phosphate over phosphocreatine, intracellular tissue pH and T2 were significantly increased compared with healthy controls. In contrast, in muscles without extensive fat replacement, only PDE/ATP and T2 values were significantly elevated. Overall, our results show that PDE levels and T2 values increase prior to the occurrence of fat replacement and remain elevated in later stages of the disease. This suggests that these individual measures could not only function as early markers for muscle damage but also reflect potentially reversible pathology in the more advanced stages.
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Affiliation(s)
- M T Hooijmans
- Department of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands
| | - E H Niks
- Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands
| | - J Burakiewicz
- Department of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands
| | - J J G M Verschuuren
- Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands
| | - A G Webb
- Department of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands
| | - H E Kan
- Department of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands
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Loehr JA, Stinnett GR, Hernández-Rivera M, Roten WT, Wilson LJ, Pautler RG, Rodney GG. Eliminating Nox2 reactive oxygen species production protects dystrophic skeletal muscle from pathological calcium influx assessed in vivo by manganese-enhanced magnetic resonance imaging. J Physiol 2016; 594:6395-6405. [PMID: 27555555 PMCID: PMC5088246 DOI: 10.1113/jp272907] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 08/12/2016] [Indexed: 01/18/2023] Open
Abstract
KEY POINTS Inhibiting Nox2 reactive oxygen species (ROS) production reduced in vivo calcium influx in dystrophic muscle. The lack of Nox2 ROS production protected against decreased in vivo muscle function in dystrophic mice. Manganese-enhanced magnetic resonance imaging (MEMRI) was able to detect alterations in basal calcium levels in skeletal muscle and differentiate disease status. Administration of Mn2+ did not affect muscle function or the health of the animal, and Mn2+ was cleared from skeletal muscle rapidly. We conclude that MEMRI may be a viable, non-invasive technique to monitor molecular alterations in disease progression and evaluate the effectiveness of potential therapies for Duchenne muscular dystrophy. ABSTRACT Duchenne muscular dystrophy (DMD) is an X-linked progressive degenerative disease resulting from a mutation in the gene that encodes dystrophin, leading to decreased muscle mechanical stability and force production. Increased Nox2 reactive oxygen species (ROS) production and sarcolemmal Ca2+ influx are early indicators of disease pathology, and eliminating Nox2 ROS production reduces aberrant Ca2+ influx in young mdx mice, a model of DMD. Various imaging modalities have been used to study dystrophic muscle in vivo; however, they are based upon alterations in muscle morphology or inflammation. Manganese has been used for indirect monitoring of calcium influx across the sarcolemma and may allow detection of molecular alterations in disease progression in vivo using manganese-enhanced magnetic resonance imaging (MEMRI). Therefore, we hypothesized that eliminating Nox2 ROS production would decrease calcium influx in adult mdx mice and that MEMRI would be able to monitor and differentiate disease status in dystrophic muscle. Both in vitro and in vivo data demonstrate that eliminating Nox2 ROS protected against aberrant Ca2+ influx and improved muscle function in dystrophic muscle. MEMRI was able to differentiate between different pathological states in vivo, with no long-term effects on animal health or muscle function. We conclude that MEMRI is a viable, non-invasive technique to differentiate disease status and might provide a means to monitor and evaluate the effectiveness of potential therapies in dystrophic muscle.
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Affiliation(s)
- James A Loehr
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA
| | - Gary R Stinnett
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA
| | | | - Wesley T Roten
- SMART Program, Baylor College of Medicine, Houston, TX, USA
- Department of Biology, University of North Carolina, Chapel Hill, NC, USA
| | - Lon J Wilson
- Department of Chemistry, Rice University, Houston, TX, USA
| | - Robia G Pautler
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA
| | - George G Rodney
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA.
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122
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Magnetic resonance imaging of the proximal upper extremity musculature in boys with Duchenne muscular dystrophy. J Neurol 2016; 264:64-71. [PMID: 27778157 DOI: 10.1007/s00415-016-8311-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 10/03/2016] [Accepted: 10/10/2016] [Indexed: 12/25/2022]
Abstract
There is a pressing need for biomarkers and outcomes that can be used across disease stages in Duchenne muscular dystrophy (DMD), to facilitate the inclusion of a wider range of participants in clinical trials and to improve our understanding of the natural history of DMD. Quantitative magnetic resonance imaging (qMRI) and spectroscopy (MRS) biomarkers show considerable promise in both the legs and forearms of individuals with DMD, but have not yet been examined in functionally important proximal upper extremity muscles such as the biceps brachii and deltoid. The primary objective of this study was to examine the feasibility of implementing qMRI and MRS biomarkers in the proximal upper extremity musculature, and the secondary objective was to examine the relationship between MR measures of arm muscle pathology and upper extremity functional endpoints. Biomarkers included MRS and MRI measures of fat fraction and transverse relaxation time (T 2). The MR exam was well tolerated in both ambulatory and non-ambulatory boys. qMR biomarkers differentiated affected and unaffected participants and correlated strongly with upper extremity function (r = 0.91 for biceps brachii T 2 versus performance of upper limb score). These qMR outcome measures could be highly beneficial to the neuromuscular disease community, allowing measurement of the quality of functionally important muscles across disease stages to understand the natural history of DMD and particularly to broaden the opportunity for clinical trial participation.
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Gaur L, Hanna A, Bandettini WP, Fischbeck KH, Arai AE, Mankodi A. Upper arm and cardiac magnetic resonance imaging in Duchenne muscular dystrophy. Ann Clin Transl Neurol 2016; 3:948-955. [PMID: 28097207 PMCID: PMC5224820 DOI: 10.1002/acn3.367] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 09/27/2016] [Accepted: 09/28/2016] [Indexed: 12/19/2022] Open
Abstract
We analyzed quantitative maps of T1 and T2 relaxation times and muscle fat fraction measurements in magnetic resonance imaging of the upper arm skeletal muscles and heart in ambulatory boys with Duchenne muscular dystrophy and age‐range‐matched healthy volunteer boys. The cardiac‐optimized sequences detected fatty infiltration and edema in the upper arm skeletal muscles but not the myocardium in these Duchenne muscular dystrophy boys who had normal ejection fraction. Imaging the heart and skeletal muscle using the same magnetic resonance imaging methods during a single scan may be useful in assessing relative disease status and therapeutic response in clinical trials of Duchenne muscular dystrophy.
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Affiliation(s)
- Lasya Gaur
- Advanced Cardiovascular Imaging National Heart, Lung and Blood Institute Bethesda Maryland; Present address: Pediatric Cardiology The Johns Hopkins Hospital Baltimore Maryland
| | - Alexander Hanna
- Advanced Cardiovascular Imaging National Heart, Lung and Blood Institute Bethesda Maryland
| | - W Patricia Bandettini
- Advanced Cardiovascular Imaging National Heart, Lung and Blood Institute Bethesda Maryland
| | - Kenneth H Fischbeck
- Neurogenetics Branch National Institute of Neurological Disorders and Stroke National Institutes of Health Bethesda Maryland
| | - Andrew E Arai
- Advanced Cardiovascular Imaging National Heart, Lung and Blood Institute Bethesda Maryland
| | - Ami Mankodi
- Neurogenetics Branch National Institute of Neurological Disorders and Stroke National Institutes of Health Bethesda Maryland
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Quantifying disease activity in fatty-infiltrated skeletal muscle by IDEAL-CPMG in Duchenne muscular dystrophy. Neuromuscul Disord 2016; 26:650-658. [PMID: 27593185 DOI: 10.1016/j.nmd.2016.07.013] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Revised: 05/27/2016] [Accepted: 07/25/2016] [Indexed: 12/17/2022]
Abstract
The purpose of this study was to explore the use of iterative decomposition of water and fat with echo asymmetry and least-squares estimation Carr-Purcell-Meiboom-Gill (IDEAL-CPMG) to simultaneously measure skeletal muscle apparent fat fraction and water T2 (T2,w) in patients with Duchenne muscular dystrophy (DMD). In twenty healthy volunteer boys and thirteen subjects with DMD, thigh muscle apparent fat fraction was measured by Dixon and IDEAL-CPMG, with the IDEAL-CPMG also providing T2,w as a measure of muscle inflammatory activity. A subset of subjects with DMD was followed up during a 48-week clinical study. The study was in compliance with the Patient Privacy Act and approved by the Institutional Review Board. Apparent fat fraction in the thigh muscles of subjects with DMD was significantly increased compared to healthy volunteer boys (p <0.001). There was a strong correlation between Dixon and IDEAL-CPMG apparent fat fraction. Muscle T2,w measured by IDEAL-CPMG was independent of changes in apparent fat fraction. Muscle T2,w was higher in the biceps femoris and vastus lateralis muscles of subjects with DMD (p <0.05). There was a strong correlation (p <0.004) between apparent fat fraction in all thigh muscles and six-minute walk distance (6MWD) in subjects with DMD. IDEAL-CPMG allowed independent and simultaneous quantification of skeletal muscle fatty degeneration and disease activity in DMD. IDEAL-CPMG apparent fat fraction and T2,w may be useful as biomarkers in clinical trials of DMD as the technique disentangles two competing biological processes.
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Straub V, Balabanov P, Bushby K, Ensini M, Goemans N, De Luca A, Pereda A, Hemmings R, Campion G, Kaye E, Arechavala-Gomeza V, Goyenvalle A, Niks E, Veldhuizen O, Furlong P, Stoyanova-Beninska V, Wood MJ, Johnson A, Mercuri E, Muntoni F, Sepodes B, Haas M, Vroom E, Aartsma-Rus A. Stakeholder cooperation to overcome challenges in orphan medicine development: the example of Duchenne muscular dystrophy. Lancet Neurol 2016; 15:882-890. [DOI: 10.1016/s1474-4422(16)30035-7] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 03/23/2016] [Accepted: 03/31/2016] [Indexed: 01/05/2023]
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McPhee KC, Wilman AH. Transverse relaxation and flip angle mapping: Evaluation of simultaneous and independent methods using multiple spin echoes. Magn Reson Med 2016; 77:2057-2065. [DOI: 10.1002/mrm.26285] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 04/29/2016] [Accepted: 05/03/2016] [Indexed: 11/06/2022]
Affiliation(s)
- Kelly C. McPhee
- Department of PhysicsUniversity of AlbertaEdmonton Alberta Canada
- Department of Biomedical EngineeringUniversity of AlbertaEdmonton Alberta Canada
| | - Alan H. Wilman
- Department of PhysicsUniversity of AlbertaEdmonton Alberta Canada
- Department of Biomedical EngineeringUniversity of AlbertaEdmonton Alberta Canada
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