1
|
Webb AJ, Birks JS, Feakins KA, Lawson A, Dawson J, Rothman AM, Werring DJ, Llwyd O, Stewart CR, Thomas J. Cerebrovascular Effects of Sildenafil in Small Vessel Disease: The OxHARP Trial. Circ Res 2024; 135:320-331. [PMID: 38832504 PMCID: PMC11227301 DOI: 10.1161/circresaha.124.324327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 04/20/2024] [Accepted: 05/14/2024] [Indexed: 06/05/2024]
Abstract
BACKGROUND Vascular cognitive impairment due to cerebral small vessel disease is associated with cerebral pulsatility, white matter hypoperfusion, and reduced cerebrovascular reactivity (CVR), and is potentially improved by endothelium-targeted drugs such as cilostazol. Whether sildenafil, a phosphodiesterase-5 inhibitor, improves cerebrovascular dysfunction is unknown. METHODS OxHARP trial (Oxford Haemodynamic Adaptation to Reduce Pulsatility) was a double-blind, randomized, placebo-controlled, 3-way crossover trial after nonembolic cerebrovascular events with mild-moderate white matter hyperintensities (WMH), the most prevalent manifestation of cerebral small vessel disease. The primary outcome assessed the superiority of 3 weeks of sildenafil 50 mg thrice daily versus placebo (mixed-effect linear models) on middle cerebral artery pulsatility, derived from peak systolic and end-diastolic velocities (transcranial ultrasound), with noninferiority to cilostazol 100 mg twice daily. Secondary end points included the following: cerebrovascular reactivity during inhalation of air, 4% and 6% CO2 on transcranial ultrasound (transcranial ultrasound-CVR); blood oxygen-level dependent-magnetic resonance imaging within WMH (CVR-WMH) and normal-appearing white matter (CVR-normal-appearing white matter); cerebral perfusion by arterial spin labeling (magnetic resonance imaging pseudocontinuous arterial spin labeling); and resistance by cerebrovascular conductance. Adverse effects were compared by Cochran Q. RESULTS In 65/75 (87%) patients (median, 70 years;79% male) with valid primary outcome data, cerebral pulsatility was unchanged on sildenafil versus placebo (0.02, -0.01 to 0.05; P=0.18), or versus cilostazol (-0.01, -0.04 to 0.02; P=0.36), despite increased blood flow (∆ peak systolic velocity, 6.3 cm/s, 3.5-9.07; P<0.001; ∆ end-diastolic velocity, 1.98, 0.66-3.29; P=0.004). Secondary outcomes improved on sildenafil versus placebo for CVR-transcranial ultrasound (0.83 cm/s per mm Hg, 0.23-1.42; P=0.007), CVR-WMH (0.07, 0-0.14; P=0.043), CVR-normal-appearing white matter (0.06, 0.00-0.12; P=0.048), perfusion (WMH: 1.82 mL/100 g per minute, 0.5-3.15; P=0.008; and normal-appearing white matter, 2.12, 0.66-3.6; P=0.006) and cerebrovascular resistance (sildenafil-placebo: 0.08, 0.05-0.10; P=4.9×10-8; cilostazol-placebo, 0.06, 0.03-0.09; P=5.1×10-5). Both drugs increased headaches (P=1.1×10-4), while cilostazol increased moderate-severe diarrhea (P=0.013). CONCLUSIONS Sildenafil did not reduce pulsatility but increased cerebrovascular reactivity and perfusion. Sildenafil merits further study to determine whether it prevents the clinical sequelae of small vessel disease. REGISTRATION URL: https://www.clinicaltrials.gov/study/NCT03855332; Unique identifier: NCT03855332.
Collapse
Affiliation(s)
- Alastair J.S. Webb
- Wolfson Centre for Prevention of Stroke and Dementia (A.J.S.W., K.A.F., A.L., O.L., C.R.S., J.T.), University of Oxford, United Kingdom
- Department of Brain Sciences, Imperial College London, United Kingdom (A.J.S.W.)
| | - Jacqueline S. Birks
- Centre for Statistics in Medicine, Botnar Research Centre (J.S.B.), University of Oxford, United Kingdom
| | - Karolina A. Feakins
- Wolfson Centre for Prevention of Stroke and Dementia (A.J.S.W., K.A.F., A.L., O.L., C.R.S., J.T.), University of Oxford, United Kingdom
| | - Amy Lawson
- Wolfson Centre for Prevention of Stroke and Dementia (A.J.S.W., K.A.F., A.L., O.L., C.R.S., J.T.), University of Oxford, United Kingdom
| | - Jesse Dawson
- School of Cardiovascular and Metabolic Health, University of Glasgow, United Kingdom (J.D.)
| | - Alexander M.K. Rothman
- Department of Cardiovascular Science, University of Sheffield, United Kingdom (A.M.K.R.)
| | - David J. Werring
- Research Department of Brain Repair and Rehabilitation, Institute of Neurology, University College London, United Kingdom (D.J.W.)
| | - Osian Llwyd
- Wolfson Centre for Prevention of Stroke and Dementia (A.J.S.W., K.A.F., A.L., O.L., C.R.S., J.T.), University of Oxford, United Kingdom
| | - Catriona R. Stewart
- Wolfson Centre for Prevention of Stroke and Dementia (A.J.S.W., K.A.F., A.L., O.L., C.R.S., J.T.), University of Oxford, United Kingdom
| | - James Thomas
- Wolfson Centre for Prevention of Stroke and Dementia (A.J.S.W., K.A.F., A.L., O.L., C.R.S., J.T.), University of Oxford, United Kingdom
| |
Collapse
|
2
|
AlRuwaili R, Al-Kuraishy HM, Alruwaili M, Khalifa AK, Alexiou A, Papadakis M, Saad HM, Batiha GES. The potential therapeutic effect of phosphodiesterase 5 inhibitors in the acute ischemic stroke (AIS). Mol Cell Biochem 2024; 479:1267-1278. [PMID: 37395897 PMCID: PMC11116240 DOI: 10.1007/s11010-023-04793-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 06/16/2023] [Indexed: 07/04/2023]
Abstract
Acute ischemic stroke (AIS) is a focal neurological disorder that accounts for 85% of all stroke types, due to occlusion of cerebral arteries by thrombosis and emboli. AIS is also developed due to cerebral hemodynamic abnormality. AIS is associated with the development of neuroinflammation which increases the severity of AIS. Phosphodiesterase enzyme (PDEs) inhibitors have neuro-restorative and neuroprotective effects against the development of AIS through modulation of the cerebral cyclic adenosine monophosphate (cAMP)/cyclic guanosine monophosphate (cGMP)/nitric oxide (NO) pathway. PDE5 inhibitors through mitigation of neuroinflammation may decrease the risk of long-term AIS-induced complications. PDE5 inhibitors may affect the hemodynamic properties and coagulation pathway which are associated with thrombotic complications in AIS. PDE5 inhibitors reduce activation of the pro-coagulant pathway and improve the microcirculatory level in patients with hemodynamic disturbances in AIS. PDE5 inhibitors mainly tadalafil and sildenafil improve clinical outcomes in AIS patients through the regulation of cerebral perfusion and cerebral blood flow (CBF). PDE5 inhibitors reduced thrombomodulin, P-selectin, and tissue plasminogen activator. Herein, PDE5 inhibitors may reduce activation of the pro-coagulant pathway and improve the microcirculatory level in patients with hemodynamic disturbances in AIS. In conclusion, PDE5 inhibitors may have potential roles in the management of AIS through modulation of CBF, cAMP/cGMP/NO pathway, neuroinflammation, and inflammatory signaling pathways. Preclinical and clinical studies are recommended in this regard.
Collapse
Affiliation(s)
- Raed AlRuwaili
- Department of Internal Medicine, College of Medicine, Jouf University, Sakaka, Saudi Arabia
| | - Hayder M Al-Kuraishy
- Department of Clinical Pharmacology and Medicine, College of Medicine, ALmustansiriyia University, Baghdad, Iraq
| | - Mubarak Alruwaili
- Department of Internal Medicine, College of Medicine, Jouf University, Sakaka, Saudi Arabia
| | - Amira Karam Khalifa
- Department of Medical Pharmacology, Kasr El-Ainy School of Medicine, Cairo University, El Manial, Cairo, 11562, Egypt
- Lecturer of Medical Pharmacology, Nahda Faculty of Medicine, Beni Suef, Egypt
| | - Athanasios Alexiou
- Department of Science and Engineering, Novel Global Community Educational Foundation, Hebersham, NSW, 2770, Australia
- AFNP Med, 1030, Vienna, Austria
| | - Marios Papadakis
- Department of Surgery II, University Hospital Witten-Herdecke, University of Witten-Herdecke, Heusnerstrasse 40, 42283, Wuppertal, Germany.
| | - Hebatallah M Saad
- Department of Pathology, Faculty of Veterinary Medicine, Matrouh University, Marsa Matrouh, 51744, Egypt
| | - Gaber El-Saber Batiha
- Department of Pharmacology and Therapeutics, Faculty of Veterinary Medicine, Damanhour University, Damanhour, 22511, AlBeheira, Egypt
| |
Collapse
|
3
|
Julien P, Zinni M, Bonnel N, El Kamouh M, Odorcyk F, Peters L, Gautier EF, Leduc M, Broussard C, Baud O. Synergistic effect of sildenafil combined with controlled hypothermia to alleviate microglial activation after neonatal hypoxia-ischemia in rats. J Neuroinflammation 2024; 21:31. [PMID: 38263116 PMCID: PMC10804557 DOI: 10.1186/s12974-024-03022-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Accepted: 01/12/2024] [Indexed: 01/25/2024] Open
Abstract
BACKGROUND AND PURPOSE The only validated treatment to prevent brain damage associated with hypoxia-ischemia (HI) encephalopathy of the newborn is controlled hypothermia with limited benefits. Additional putative neuroprotective drug candidates include sildenafil citrate, a phosphodiesterase-type 5 inhibitor. The main objective of this preclinical study is to assess its ability to reduce HI-induced neuroinflammation, in particular through its potential effect on microglial activation. METHODS HI was induced in P10 Sprague-Dawley rats by unilateral carotid permanent artery occlusion and hypoxia (HI) and treated by either hypothermia (HT) alone, Sildenafil (Sild) alone or combined treatment (SildHT). Lesion size and glial activation were analyzed by immunohistochemistry, qRT-PCR, and proteomic analyses performed at P13. RESULTS None of the treatments was associated with a significant early reduction in lesion size 72h after HI, despite significant changes in tissue loss distribution. Significant reductions in both Iba1 + (within the ipsilateral hemisphere) and GFAP + cells (within the ipsilateral hippocampus) were observed in SildHT group, but not in the other treatment groups. In microglia-sorted cells, pro-inflammatory markers, i.e. Il1b, Il6, Nos2, and CD86 were significantly downregulated in SildHT treatment group only. These changes were restricted to the ipsilateral hemisphere, were not evidenced in sorted astrocytes, and were not sex dependent. Proteomic analyses in sorted microglia refined the pro-inflammatory effect of HI and confirmed a biologically relevant impact of SildHT on specific molecular pathways including genes related to neutrophilic functions. CONCLUSIONS Our findings suggest that Sildenafil combined with controlled hypothermia produces maximum effect in mitigating microglial activation induced by HI through complex proteomic regulation. The reduction of neuroinflammation induced by Sildenafil may represent an interesting therapeutic strategy for neonatal neuroprotection.
Collapse
Affiliation(s)
- Pansiot Julien
- Inserm UMR1141 NeuroDiderot, Université Paris Cité, Paris, France
| | - Manuela Zinni
- Inserm UMR1141 NeuroDiderot, Université Paris Cité, Paris, France
| | - Natacha Bonnel
- Inserm UMR1141 NeuroDiderot, Université Paris Cité, Paris, France
| | - Marina El Kamouh
- Inserm UMR1141 NeuroDiderot, Université Paris Cité, Paris, France
| | - Felipe Odorcyk
- Inserm UMR1141 NeuroDiderot, Université Paris Cité, Paris, France
| | - Lea Peters
- Inserm UMR1141 NeuroDiderot, Université Paris Cité, Paris, France
| | - Emilie-Fleur Gautier
- Institut Cochin, Proteom'IC Facility, INSERM, CNRS, Université Paris Cité, Paris, France
| | - Marjorie Leduc
- Institut Cochin, Proteom'IC Facility, INSERM, CNRS, Université Paris Cité, Paris, France
| | - Cédric Broussard
- Institut Cochin, Proteom'IC Facility, INSERM, CNRS, Université Paris Cité, Paris, France
| | - Olivier Baud
- Inserm UMR1141 NeuroDiderot, Université Paris Cité, Paris, France.
- Laboratory of Child Growth and Development, University of Geneva, Geneva, Switzerland.
- Division of Neonatology and Pediatric Intensive Care, Département de Pédiatrie, Hôpitaux Universitaires de Genève, Laboratoire de Développement et Croissance, Children's University Hospital of Geneva, Geneva, Switzerland.
| |
Collapse
|
4
|
Wang Q, Shin B, Oh S, Shin YS, Na DL, Kim KW. A pilot study to explore the effect of udenafil on cerebral hemodynamics in older adults. Ann Clin Transl Neurol 2023; 10:933-943. [PMID: 37013976 PMCID: PMC10270257 DOI: 10.1002/acn3.51774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 03/17/2023] [Accepted: 03/18/2023] [Indexed: 04/05/2023] Open
Abstract
OBJECTIVE Phosphodiesterase-5 inhibitors (PDE5Is) enhance vasodilation. We investigated the effects of PDE5I on cerebral hemodynamics during cognitive tasks using functional near-infrared spectroscopy (fNIRS). METHODS This study used a crossover design. Twelve cognitively healthy men participants (mean age, 59 ± 3 years; range, 55-65 years) were recruited and randomly assigned to the experimental or control arm, then the experimental and control arm were exchanged after 1 week. Udenafil 100 mg was administered to participants in the experimental arm once daily for 3 days. We measured the fNIRS signal during the resting state and four cognitive tasks three times for each participant: at baseline, in the experimental arm, and in the control arm. RESULTS Behavioral data did not show a significant difference between the experimental and control arms. The fNIRS signal showed significant decreases in the experimental arm compared to the control arm during several cognitive tests: verbal fluency test (left dorsolateral prefrontal cortex, T = -3.02, p = 0.014; left frontopolar cortex, T = -4.37, p = 0.002; right dorsolateral prefrontal cortex, T = -2.59, p = 0.027), Korean-color word Stroop test (left orbitofrontal cortex, T = -3.61, p = 0.009), and social event memory test (left dorsolateral prefrontal cortex, T = -2.35, p = 0.043; left frontopolar cortex, T = -3.35, p = 0.01). INTERPRETATION Our results showed a paradoxical effect of udenafil on cerebral hemodynamics in older adults. This contradicts our hypothesis, but it suggests that fNIRS is sensitive to changes in cerebral hemodynamics in response to PDE5Is.
Collapse
Affiliation(s)
- Qi Wang
- Medical SchoolJeonbuk National UniversityJeonjuSouth Korea
| | - Byoung‐Soo Shin
- Department of NeurologyJeonbuk National University Medical School and HospitalJeonjuSouth Korea
- Research Institute of Clinical Medicine of Jeonbuk National University‐Biomedical Research Institute of Jeonbuk National University HospitalJeonjuSouth Korea
| | - Sun‐Young Oh
- Department of NeurologyJeonbuk National University Medical School and HospitalJeonjuSouth Korea
- Research Institute of Clinical Medicine of Jeonbuk National University‐Biomedical Research Institute of Jeonbuk National University HospitalJeonjuSouth Korea
| | - Yu Seob Shin
- Research Institute of Clinical Medicine of Jeonbuk National University‐Biomedical Research Institute of Jeonbuk National University HospitalJeonjuSouth Korea
- Department of UrologyJeonbuk National University Medical School and HospitalJeonjuSouth Korea
| | - Duk L. Na
- Department of NeurologySungkyunkwan University School of Medicine, Samsung Medical CenterSeoulSouth Korea
| | - Ko Woon Kim
- Department of NeurologyJeonbuk National University Medical School and HospitalJeonjuSouth Korea
- Research Institute of Clinical Medicine of Jeonbuk National University‐Biomedical Research Institute of Jeonbuk National University HospitalJeonjuSouth Korea
| |
Collapse
|
5
|
Inocencio IM, Kaur N, Tran NT, Wong FY. Cerebral haemodynamic response to somatosensory stimulation in preterm lambs is enhanced following sildenafil and inhaled nitric oxide administration. Front Physiol 2023; 14:1101647. [PMID: 36760535 PMCID: PMC9905131 DOI: 10.3389/fphys.2023.1101647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 01/11/2023] [Indexed: 01/26/2023] Open
Abstract
Background: Neurovascular coupling (NVC) leads to an increase in local cerebral blood flow and oxygenation in response to increased neural activity and metabolic demand. Impaired or immature NVC reported in the preterm brain, potentially reduces cerebral oxygenation following increased neural activity, predisposing to cerebral tissue hypoxia. Endogenous nitric oxide (NO) is a potent vasodilator and a major mediator of NVC and the cerebral haemodynamic response. NO modulators, such as inhaled nitric oxide (iNO) and sildenafil, induce vasodilation and are used clinically to treat pulmonary hypertension in preterm neonates. However, their impact on NVC in the preterm brain are unknown. We aimed to characterise the cerebral functional haemodynamic response in the preterm brain exposed to NO modulators. We hypothesized that iNO and sildenafil in clinical dosages would increase the baseline cerebral perfusion and the cerebral haemodynamic response to neural activation. Methods: Preterm lambs (126-7 days' gestation) were delivered and mechanically ventilated. The cerebral functional haemodynamic response was measured using near infrared spectroscopy as changes in cerebral oxy- and deoxyhaemoglobin (ΔoxyHb, ΔdeoxyHb), following left median nerve stimulations of 1.8, 4.8, and 7.8 s durations in control preterm lambs (n = 11), and following 4.8 and 7.8 s stimulations in preterm lambs receiving either sildenafil citrate (n = 6, 1.33 mcg/kg/hr) or iNO (n = 8, 20 ppm). Results: Following 1.8, 4.8, and 7.8 s stimulations, ∆oxyHb in the contralateral cortex increased (positive functional response) in 7/11 (64%), 7/11 (64%), and 4/11 (36%) control lambs respectively (p < 0.05). Remaining lambs showed decreased ΔoxyHb (negative functional response). Following 4.8 s stimulations, more lambs receiving sildenafil or iNO (83% and 100% respectively) showed positive functional response compared to the controls (p < 0.05). No significant difference between the three groups was observed at 7.8 s stimulations. Conclusion: In the preterm brain, prolonged somatosensory stimulations increased the incidence of negative functional responses with decreased cerebral oxygenation, suggesting that cerebral oxygen delivery may not match the oxygen demand. Sildenafil and iNO increased the incidence of positive functional responses, potentially enhancing NVC, and cerebral oxygenation.
Collapse
Affiliation(s)
- Ishmael Miguel Inocencio
- The Ritchie Centre, The Hudson Institute of Medical Research, Melbourne, VIC, Australia,Department of Paediatrics, Monash University, Melbourne, VIC, Australia
| | - Navneet Kaur
- The Ritchie Centre, The Hudson Institute of Medical Research, Melbourne, VIC, Australia,Department of Paediatrics, Monash University, Melbourne, VIC, Australia
| | - Nhi T. Tran
- The Ritchie Centre, The Hudson Institute of Medical Research, Melbourne, VIC, Australia
| | - Flora Y. Wong
- The Ritchie Centre, The Hudson Institute of Medical Research, Melbourne, VIC, Australia,Department of Paediatrics, Monash University, Melbourne, VIC, Australia,Monash Newborn, Monash Children’s Hospital, Melbourne, VIC, Australia,*Correspondence: Flora Y. Wong,
| |
Collapse
|
6
|
Pauls MMH, Binnie LR, Benjamin P, Betteridge S, Clarke B, Dhillon MPK, Ghatala R, Hainsworth FAH, Howe FA, Khan U, Kruuse C, Madigan JB, Moynihan B, Patel B, Pereira AC, Rostrup E, Shtaya ABY, Spilling CA, Trippier S, Williams R, Young R, Barrick TR, Isaacs JD, Hainsworth AH. The PASTIS trial: Testing tadalafil for possible use in vascular cognitive impairment. Alzheimers Dement 2022; 18:2393-2402. [PMID: 35135037 PMCID: PMC10078742 DOI: 10.1002/alz.12559] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 10/13/2021] [Accepted: 12/07/2021] [Indexed: 01/31/2023]
Abstract
INTRODUCTION There are few randomized clinical trials in vascular cognitive impairment (VCI). This trial tested the hypothesis that the PDE5 inhibitor tadalafil, a widely used vasodilator, increases cerebral blood flow (CBF) in older people with symptomatic small vessel disease, the main cause of VCI. METHODS In a double-blind, placebo-controlled, cross-over trial, participants received tadalafil (20 mg) and placebo on two visits ≥7 days apart (randomized to order of treatment). The primary endpoint, change in subcortical CBF, was measured by arterial spin labelling. RESULTS Tadalafil increased CBF non-significantly in all subcortical areas (N = 55, age: 66.8 (8.6) years) with greatest treatment effect within white matter hyperintensities (+9.8%, P = .0960). There were incidental treatment effects on systolic and diastolic blood pressure (-7.8, -4.9 mmHg; P < .001). No serious adverse events were observed. DISCUSSION This trial did not identify a significant treatment effect of single-administration tadalafil on subcortical CBF. To detect treatment effects may require different dosing regimens.
Collapse
Affiliation(s)
- Mathilde M H Pauls
- Molecular & Clinical Sciences Research Institute, St George's University of London, London, UK.,Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Lauren R Binnie
- Molecular & Clinical Sciences Research Institute, St George's University of London, London, UK
| | - Philip Benjamin
- Molecular & Clinical Sciences Research Institute, St George's University of London, London, UK.,Department of Neuroradiology, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Shai Betteridge
- Department of Neuropsychology, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Brian Clarke
- Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Mohani-Preet K Dhillon
- Molecular & Clinical Sciences Research Institute, St George's University of London, London, UK
| | - Rita Ghatala
- South London Stroke Research Network, London, UK
| | - Fearghal A H Hainsworth
- Molecular & Clinical Sciences Research Institute, St George's University of London, London, UK
| | - Franklyn A Howe
- Molecular & Clinical Sciences Research Institute, St George's University of London, London, UK
| | - Usman Khan
- Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Christina Kruuse
- Department of Neurology and Neurovascular Research Unit, Herlev Gentofte Hospital, Hellerup, Denmark
| | - Jeremy B Madigan
- Department of Neuroradiology, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Barry Moynihan
- Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK.,Department of Medicine, Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin, Ireland
| | - Bhavini Patel
- Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Anthony C Pereira
- Molecular & Clinical Sciences Research Institute, St George's University of London, London, UK.,Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Egill Rostrup
- Mental Health Centre, University of Copenhagen, Glostrup, Denmark
| | - Anan B Y Shtaya
- Molecular & Clinical Sciences Research Institute, St George's University of London, London, UK
| | - Catherine A Spilling
- Molecular & Clinical Sciences Research Institute, St George's University of London, London, UK
| | | | | | - Robin Young
- Robertson Centre for Biostatistics, University of Glasgow, Glasgow, UK
| | - Thomas R Barrick
- Molecular & Clinical Sciences Research Institute, St George's University of London, London, UK
| | - Jeremy D Isaacs
- Molecular & Clinical Sciences Research Institute, St George's University of London, London, UK.,Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Atticus H Hainsworth
- Molecular & Clinical Sciences Research Institute, St George's University of London, London, UK.,Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK
| |
Collapse
|
7
|
Xiong Y, Wintermark P. The Role of Sildenafil in Treating Brain Injuries in Adults and Neonates. Front Cell Neurosci 2022; 16:879649. [PMID: 35620219 PMCID: PMC9127063 DOI: 10.3389/fncel.2022.879649] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Accepted: 04/04/2022] [Indexed: 12/02/2022] Open
Abstract
Sildenafil is a recognized treatment for patients suffering from erectile dysfunction and pulmonary hypertension. However, new evidence suggests that it may have a neuroprotective and a neurorestorative role in the central nervous system of both adults and neonates. Phosphodiesterase type 5-the target of sildenafil-is distributed in many cells throughout the body, including neurons and glial cells. This study is a comprehensive review of the demonstrated effects of sildenafil on the brain with respect to its function, extent of injury, neurons, neuroinflammation, myelination, and cerebral vessels.
Collapse
Affiliation(s)
- Ying Xiong
- Department of Anesthesiology, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan, China
- Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | - Pia Wintermark
- Research Institute of the McGill University Health Centre, Montreal, QC, Canada
- Division of Newborn Medicine, Department of Pediatrics, Montreal Children’s Hospital, Montreal, QC, Canada
| |
Collapse
|
8
|
Hendriksen JGM, Thangarajh M, Kan HE, Muntoni F. 249th ENMC International Workshop: The role of brain dystrophin in muscular dystrophy: Implications for clinical care and translational research, Hoofddorp, The Netherlands, November 29th-December 1st 2019. Neuromuscul Disord 2020; 30:782-794. [PMID: 32912717 DOI: 10.1016/j.nmd.2020.08.357] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 07/27/2020] [Accepted: 08/10/2020] [Indexed: 01/16/2023]
Affiliation(s)
- Jos G M Hendriksen
- Kempenhaeghe Center For Neurological Learning Disabilities, Heeze, the Netherlands; Duchenne Center, the Netherlands
| | - Mathula Thangarajh
- Department of Neurology, Virginia Commonwealth University, Richmond, USA
| | - Hermien E Kan
- Duchenne Center, the Netherlands; C.J. Gorter Center for High Field MRI, Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands.
| | - Francesco Muntoni
- The Dubowitz Neuromuscular Centre, University College London, Great Ormond Street Institute of Child Health, London, UK; NIHR Great Ormond Street Hospital Biomedical Research Centre, London, UK
| |
Collapse
|
9
|
Vasita E, Yasmeen S, Andoh J, Bridges LR, Kruuse C, Pauls MMH, Pereira AC, Hainsworth AH. The cGMP-Degrading Enzyme Phosphodiesterase-5 (PDE5) in Cerebral Small Arteries of Older People. J Neuropathol Exp Neurol 2019; 78:191-194. [PMID: 30590671 DOI: 10.1093/jnen/nly117] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/27/2024] Open
Abstract
Cerebral small vessel disease in deep penetrating arteries is a major cause of lacunar infarcts, white matter lesions and vascular cognitive impairment. Local cerebral blood flow in these small vessels is controlled by endothelial-derived nitric oxide, which exerts a primary vasodilator stimulus on vascular myocytes, via cytoplasmic cyclic GMP. Here, we investigated whether the cGMP-degrading enzyme phosphodiesterase-5 (PDE5) is present in small penetrating arteries in the deep subcortical white matter of older people. Frontal cortical tissue blocks were examined from donated brains of older people (n = 42, 24 male: 18 female, median age 81, range: 59-100 years). PDE5, detected by immunohistochemical labeling, was graded as absent, sparse, or abundant in vascular cells within small arteries in subcortical white matter (vessel outer diameter: 20-100 µm). PDE5 labeling within arterial myocytes was detected in all cases. Degree of PDE5 expression (absent, sparse, or abundant) was not associated with age or with neuropathological diagnosis of small vessel disease. In conclusion, PDE5 is present in vascular myocytes within small penetrating arteries in older people. This is a potential molecular target for pharmacological interventions.
Collapse
Affiliation(s)
- Ekta Vasita
- Molecular and Clinical Sciences Research Institute, St. Georges University of London, London, United Kingdom
| | - Saiqa Yasmeen
- Department of Neurology, Herlev Hospital, Herlev Ringvej 75, 2730 Herlev, Denmark
| | - Joycelyn Andoh
- Molecular and Clinical Sciences Research Institute, St. Georges University of London, London, United Kingdom
| | - Leslie R Bridges
- Department of Cellular Pathology, St. George's University Hospitals NHS Foundation Trust, Blackshaw Road, SW17 0QT, London, United Kingdom
| | - Christina Kruuse
- Department of Neurology, Herlev Hospital, Herlev Ringvej 75, 2730 Herlev, Denmark
| | - Mathilde M H Pauls
- Molecular and Clinical Sciences Research Institute, St. Georges University of London, London, United Kingdom
| | - Anthony C Pereira
- Department of Neurology, St. George's University Hospitals NHS Foundation Trust, London, Blackshaw Road, SW17 0QT, United Kingdom
| | - Atticus H Hainsworth
- Molecular and Clinical Sciences Research Institute, St. Georges University of London, London, United Kingdom
| |
Collapse
|
10
|
Effects of vasodilating medications on cerebral haemodynamics in health and disease: systematic review and meta-analysis. J Hypertens 2018; 37:1119-1125. [PMID: 30540658 PMCID: PMC6513078 DOI: 10.1097/hjh.0000000000002033] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Objectives: Vasodilating antihypertensives prevent stroke and potentially cerebral small vessel disease but their effects on cerebrovascular haemodynamics beyond blood pressure lowering are unclear. Methods: We searched PubMed, Medline, Embase, Cinahl, Psychinfo, Health Business Elite and Health Management Information Consortium for randomized studies of vasodilating medications, compared to no treatment or nonvasodilators, that reported effects on cerebral blood flow (CBF), mean blood flow velocity (MFV) or cerebrovascular reactivity. Absolute and standardized mean differences (SMD) were combined by inverse-variance weighted fixed or random-effects meta-analysis stratified by study design, population characteristics and vasodilator class. Results: In 35 studies reporting 57 comparisons, there was a reduction in SBP (−4.13 mmHg, −7.55 to −0.71, P = 0.018) but no change in MFV (ΔMFV 1.11, confidence interval −0.93 to 3.14, P = 0.29, 23 comparisons). MFV increased in patients with underlying conditions (3.41, 0.24 to 6.57, P = 0.04) but not in healthy study participants (−1.27, −5.18 to 2.64, P = 0.68), with no differences by vasodilating drug class. Cerebral pulsatility index was reduced across all studies (Δ pulsatility index −0.04, −0.07 to −0.02, P = 0.001; Δ pulsatility index -SMD −0.32, −0.47 to −0.16, P < 0.001), except in studies reporting responses to single drug doses (Δ pulsatility index 0.00, −0.09 to −0.08, P = 0.93). Despite evidence of reporting and publication bias, there was an apparent consistent reduction in CBF with vasodilators (CBF-SMD −0.24, −0.46 to −0.02, P = 0.03) with a significant increase in cerebrovascular reactivity-SMD (0.48, 0.13–0.83, P = 0.007). Conclusions: Despite reducing SBP, vasodilators did not significantly impair absolute CBF but improved cerebrovascular pulsatility and reactivity, suggesting therapeutic potential in preventing stroke and cerebral small vessel disease.
Collapse
|
11
|
Dombernowsky NW, Ölmestig JNE, Witting N, Kruuse C. Role of neuronal nitric oxide synthase (nNOS) in Duchenne and Becker muscular dystrophies - Still a possible treatment modality? Neuromuscul Disord 2018; 28:914-926. [PMID: 30352768 DOI: 10.1016/j.nmd.2018.09.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 08/07/2018] [Accepted: 09/05/2018] [Indexed: 02/08/2023]
Abstract
Neuronal nitric oxide synthase (nNOS) is involved in nitric oxide (NO) production and suggested to play a crucial role in blood flow regulation of skeletal muscle. During activation of the muscle, NO helps attenuate the sympathetic vasoconstriction to accommodate increased metabolic demands, a phenomenon known as functional sympatholysis. In inherited myopathies such as the dystrophinopathies Duchenne and Becker muscle dystrophies (DMD and BMD), nNOS is lost from the sarcolemma. The loss of nNOS may cause functional ischemia contributing to skeletal and cardiac muscle cell injury. Effects of NO is augmented by inhibiting degradation of the second messenger cyclic guanosine monophosphate (cGMP) using sildenafil and tadalafil, both of which inhibit the enzyme phosphodiesterase 5 (PDE5). In animal models of DMD, PDE5-inhibitors prevent functional ischemia, reduce post-exercise skeletal muscle pathology and fatigue, show amelioration of cardiac muscle cell damage and increase cardiac performance. However, effect on clinical outcomes in DMD and BMD patients have been disappointing with minor effects on upper limb performance and none on ambulation. This review aims to summarize the current knowledge of nNOS function related to functional sympatholysis in skeletal muscle and studies on PDE5-inhibitor treatment in nNOS-deficient animal models and patients.
Collapse
Affiliation(s)
- Nanna W Dombernowsky
- Department of Neurology, Rigshospitalet Glostrup, University of Copenhagen, Denmark
| | - Joakim N E Ölmestig
- Department of Neurology, Neurovascular Research Unit, Herlev Gentofte Hospital, University of Copenhagen, Denmark
| | - Nanna Witting
- Department of Neurology, Rigshospitalet Glostrup, University of Copenhagen, Denmark
| | - Christina Kruuse
- Department of Neurology, Neurovascular Research Unit, Herlev Gentofte Hospital, University of Copenhagen, Denmark; PDE Research Group, Lundbeck Foundation Center for Neurovascular Research (LUCENS), Denmark.
| |
Collapse
|
12
|
Lindberg U, Kruuse C, Witting N, Jørgensen SL, Vissing J, Rostrup E, Larsson HBW. Altered somatosensory neurovascular response in patients with Becker muscular dystrophy. Brain Behav 2018; 8:e00985. [PMID: 30106246 PMCID: PMC5991560 DOI: 10.1002/brb3.985] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 02/12/2018] [Accepted: 03/31/2018] [Indexed: 01/19/2023] Open
Abstract
INTRODUCTION Patients with dystrophinopathies show low levels of neuronal nitric oxide synthase (nNOS), due to reduced or absent dystrophin expression, as nNOS is attached to the dystrophin-associated protein complex. Deficient nNOS function leads to functional ischemia during muscle activity. Dystrophin-like proteins with nNOS attached have also been identified in the brain. This suggests that a mechanism of cerebral functional ischemia with attenuation of normal activation-related vascular response may cause changes in brain function. METHODS The aim of this study was to investigate whether the brain response of patients with Becker muscular dystrophy (BMD) is dysfunctional compared to that of healthy controls. To investigate a potential change in brain activation response in patients with BMD, median nerve somatosensory evoked stimulation, with stimulation durations of 2, 4, and 10 s, was performed while recording electroencephalography and blood oxygen level-dependent (BOLD) functional magnetic resonance imaging. RESULTS Results in 14 male patients with BMD (36.2 ± 9.9 years) were compared with those of 10 healthy controls (34.4 ± 10.9 years). Compared to controls, the patients with BMD showed sustained cortical electrical activity and a significant smaller BOLD activation in contralateral primary somatosensory cortex and bilaterally in secondary somatosensory cortex. In addition, significant activation differences were found after long duration (10 s) stimuli in thalamus. CONCLUSION An altered neurovascular response in patients with BMD may increase our understanding of neurovascular coupling and the pathogenesis related to dystrophinopathy and nNOS.
Collapse
Affiliation(s)
- Ulrich Lindberg
- Functional Imaging UnitDepartment of Clinical PhysiologyNuclear Medicine and PETRigshospitalet GlostrupUniversity of CopenhagenGlostrupDenmark
- Lundbeck Foundation Center for Neurovascular signalling (LUCENS)Rigshospitalet GlostrupUniversity of CopenhagenGlostrupDenmark
| | - Christina Kruuse
- Lundbeck Foundation Center for Neurovascular signalling (LUCENS)Rigshospitalet GlostrupUniversity of CopenhagenGlostrupDenmark
- Neurovascular Research UnitDepartment of NeurologyHerlev Gentofte HospitalUniversity of CopenhagenHerlevDenmark
| | - Nanna Witting
- Copenhagen Neuromuscular CenterDepartment of NeurologyRigshospitaletUniversity of CopenhagenDenmark
| | - Stine Lundgaard Jørgensen
- Lundbeck Foundation Center for Neurovascular signalling (LUCENS)Rigshospitalet GlostrupUniversity of CopenhagenGlostrupDenmark
- Neurovascular Research UnitDepartment of NeurologyHerlev Gentofte HospitalUniversity of CopenhagenHerlevDenmark
| | - John Vissing
- Copenhagen Neuromuscular CenterDepartment of NeurologyRigshospitaletUniversity of CopenhagenDenmark
| | - Egill Rostrup
- Functional Imaging UnitDepartment of Clinical PhysiologyNuclear Medicine and PETRigshospitalet GlostrupUniversity of CopenhagenGlostrupDenmark
| | - Henrik Bo Wiberg Larsson
- Functional Imaging UnitDepartment of Clinical PhysiologyNuclear Medicine and PETRigshospitalet GlostrupUniversity of CopenhagenGlostrupDenmark
- Lundbeck Foundation Center for Neurovascular signalling (LUCENS)Rigshospitalet GlostrupUniversity of CopenhagenGlostrupDenmark
| |
Collapse
|
13
|
Pauls MMH, Moynihan B, Barrick TR, Kruuse C, Madigan JB, Hainsworth AH, Isaacs JD. The effect of phosphodiesterase-5 inhibitors on cerebral blood flow in humans: A systematic review. J Cereb Blood Flow Metab 2018; 38:189-203. [PMID: 29256324 PMCID: PMC5951021 DOI: 10.1177/0271678x17747177] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 10/17/2017] [Accepted: 10/20/2017] [Indexed: 11/29/2022]
Abstract
Agents that augment cerebral blood flow (CBF) could be potential treatments for vascular cognitive impairment. Phosphodiesterase-5 inhibitors are vasodilating drugs established in the treatment of erectile dysfunction (ED) and pulmonary hypertension. We reviewed published data on the effects of phosphodiesterase-5 inhibitors on CBF in adult humans. A systematic review according to PRISMA guidelines was performed. Embase, Medline and Cochrane Library Trials databases were searched. Sixteen studies with 353 participants in total were retrieved. Studies included healthy volunteers and patients with migraine, ED, type 2 diabetes, stroke, pulmonary hypertension, Becker muscular dystrophy and subarachnoid haemorrhage. Most studies used middle cerebral artery flow velocity to estimate CBF. Few studies employed direct measurements of tissue perfusion. Resting CBF velocity was unaffected by phosphodiesterase-5 inhibitors, but cerebrovascular regulation was improved in ED, pulmonary hypertension, diabetes, Becker's and a group of healthy volunteers. This evidence suggests that phosphodiesterase-5 inhibitors improve responsiveness of the cerebral vasculature, particularly in disease states associated with an impaired endothelial dilatory response. This supports the potential therapeutic use of phosphodiesterase-5 inhibitors in vascular cognitive impairment where CBF is reduced. Further studies with better resolution of deep CBF are warranted. The review is registered on the PROSPERO database (registration number CRD42016029668).
Collapse
Affiliation(s)
- Mathilde MH Pauls
- Molecular and Clinical Sciences Research
Institute, St George's University of London, London, UK
- Department of Neurology, St George's
University Hospitals NHS Foundation Trust, London, UK
| | - Barry Moynihan
- Department of Neurology, St George's
University Hospitals NHS Foundation Trust, London, UK
- Department of Geriatric and Stroke
Medicine, Beaumont Hospital, Dublin, Ireland
| | - Thomas R Barrick
- Molecular and Clinical Sciences Research
Institute, St George's University of London, London, UK
| | - Christina Kruuse
- Department of Neurology, Neurovascular
Research Unit, Herlev Gentofte Hospital and University of Copenhagen, Denmark
| | - Jeremy B Madigan
- Department of Neuroradiology, St
George's University Hospitals NHS Foundation Trust, London, UK
| | - Atticus H Hainsworth
- Molecular and Clinical Sciences Research
Institute, St George's University of London, London, UK
- Department of Neurology, St George's
University Hospitals NHS Foundation Trust, London, UK
| | - Jeremy D Isaacs
- Molecular and Clinical Sciences Research
Institute, St George's University of London, London, UK
- Department of Neurology, St George's
University Hospitals NHS Foundation Trust, London, UK
| |
Collapse
|
14
|
Mavrogeni S, Pons R, Nikas I, Papadopoulos G, Verganelakis DA, Kolovou G, Chrousos GP. Brain and heart magnetic resonance imaging/spectroscopy in duchenne muscular dystrophy. Eur J Clin Invest 2017; 47. [PMID: 28981141 DOI: 10.1111/eci.12842] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2017] [Accepted: 10/02/2017] [Indexed: 01/04/2023]
Abstract
Duchenne muscular dystrophy (DMD) is an X-linked muscle disorder characterized by progressive and irreversible loss of muscular function. As muscular disease progresses, the repair mechanisms cannot compensate for cellular damage, leading inevitably to necrosis and progressive replacement by fibrous and fatty tissue. Cardiomyopathy and respiratory failure are the main causes of death in DMD. In addition to the well-described muscle and heart disease, cognitive dysfunction affects around 30% of DMD boys. Myocardial fibrosis, assessed by late gadolinium enhancement (LGE), using cardiovascular magnetic resonance imaging (CMR), is an early marker of heart involvement in both DMD patients and female carriers. In parallel, brain MRI identifies smaller total brain volume, smaller grey matter volume, lower white matter fractional anisotropy and higher white matter radial diffusivity in DMD patients. The in vivo brain evaluation of mdx mice, a surrogate animal model of DMD, showed an increased inorganic phosphate (P(i))/phosphocreatine (PCr) and pH. In this paper, we propose a holistic approach using techniques of magnetic resonance imaging, spectroscopy and diffusion tensor imaging as a tool to create a "heart and brain imaging map" in DMD patients that could potentially facilitate the patients' risk stratification and also future research studies in the field.
Collapse
Affiliation(s)
| | - Roser Pons
- 1st Department of Pediatrics, National and Kapodistrian University of Athens, Aghia Sophia Children's Hospital, Athens, Greece
| | - Ioannis Nikas
- 1st Department of Pediatrics, National and Kapodistrian University of Athens, Aghia Sophia Children's Hospital, Athens, Greece
| | - George Papadopoulos
- 1st Department of Pediatrics, National and Kapodistrian University of Athens, Aghia Sophia Children's Hospital, Athens, Greece
| | - Dimitrios A Verganelakis
- 1st Department of Pediatrics, National and Kapodistrian University of Athens, Aghia Sophia Children's Hospital, Athens, Greece
| | | | - George P Chrousos
- 1st Department of Pediatrics, National and Kapodistrian University of Athens, Aghia Sophia Children's Hospital, Athens, Greece
| |
Collapse
|
15
|
Doorenweerd N, Dumas EM, Ghariq E, Schmid S, Straathof CSM, Roest AAW, Wokke BH, van Zwet EW, Webb AG, Hendriksen JGM, van Buchem MA, Verschuuren JJGM, Asllani I, Niks EH, van Osch MJP, Kan HE. Decreased cerebral perfusion in Duchenne muscular dystrophy patients. Neuromuscul Disord 2016; 27:29-37. [PMID: 27927595 DOI: 10.1016/j.nmd.2016.10.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 08/17/2016] [Accepted: 10/11/2016] [Indexed: 10/20/2022]
Abstract
Duchenne muscular dystrophy is caused by dystrophin gene mutations which lead to the absence of the protein dystrophin. A significant proportion of patients suffer from learning and behavioural disabilities, in addition to muscle weakness. We have previously shown that these patients have a smaller total brain and grey matter volume, and altered white matter microstructure compared to healthy controls. Patients with more distal gene mutations, predicted to affect dystrophin isoforms Dp140 and Dp427, showed greater grey matter reduction. Now, we studied if cerebral blood flow in Duchenne muscular dystrophy patients is altered, since cerebral expression of dystrophin also occurs in vascular endothelial cells and astrocytes associated with cerebral vasculature. T1-weighted anatomical and pseudo-continuous arterial spin labeling cerebral blood flow images were obtained from 26 patients and 19 age-matched controls (ages 8-18 years) on a 3 tesla MRI scanner. Group comparisons of cerebral blood flow were made with and without correcting for grey matter volume using partial volume correction. Results showed that patients had a lower cerebral blood flow than controls (40.0 ± 6.4 and 47.8 ± 6.3 mL/100 g/min respectively, p = 0.0002). This reduction was independent of grey matter volume, suggesting that they are two different aspects of the pathophysiology. Cerebral blood flow was lowest in patients lacking Dp140. There was no difference in CBF between ambulant and non-ambulant patients. Only three patients showed a reduced left ventricular ejection fraction. No correlation between cerebral blood flow and age was found. Our results indicate that cerebral perfusion is reduced in Duchenne muscular dystrophy patients independent of the reduced grey matter volume.
Collapse
Affiliation(s)
- Nathalie Doorenweerd
- Department of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands; Leiden Institute for Brain and Cognition, Leiden, The Netherlands; Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands.
| | - Eve M Dumas
- Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands
| | - Eidrees Ghariq
- Department of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands; Leiden Institute for Brain and Cognition, Leiden, The Netherlands
| | - Sophie Schmid
- Department of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands; Leiden Institute for Brain and Cognition, Leiden, The Netherlands
| | - Chiara S M Straathof
- Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands
| | - Arno A W Roest
- Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands
| | - Beatrijs H Wokke
- Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands
| | - Erik W van Zwet
- Department of Medical Statistics, Leiden University Medical Center, Leiden, The Netherlands
| | - Andrew G Webb
- Department of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands
| | - Jos G M Hendriksen
- Department of Medical Statistics, Leiden University Medical Center, Leiden, The Netherlands; Department of Neurology, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Mark A van Buchem
- Department of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Iris Asllani
- Department of Biomedical Engineering, Rochester Institute of Technology, Rochester, NY, USA
| | - Erik H Niks
- Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands
| | - Matthias J P van Osch
- Department of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands; Leiden Institute for Brain and Cognition, Leiden, The Netherlands
| | - Hermien E Kan
- Department of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands; Leiden Institute for Brain and Cognition, Leiden, The Netherlands
| |
Collapse
|