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Raffaelli B, Do TP, Ashina H, Snellman J, Maio-Twofoot T, Ashina M. Induction of cGMP-mediated migraine attacks is independent of CGRP receptor activation. Cephalalgia 2024; 44:3331024241259489. [PMID: 38850034 DOI: 10.1177/03331024241259489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2024]
Abstract
BACKGROUND The cAMP and cGMP pathways are implicated in the initiation of migraine attacks, but their interactions remain unclear. Calcitonin gene-related peptide (CGRP) triggers migraine attacks via cAMP, whereas the phosphodiesterase-5 inhibitor sildenafil induces migraine attacks via cGMP. Our objective was to investigate whether sildenafil could induce migraine attacks in individuals with migraine pre-treated with the CGRP-receptor antibody erenumab. METHODS In this randomized, double-blind, placebo-controlled, cross-over study, adults with migraine without aura received a single subcutaneous injection of 140 mg erenumab on day 1. They were then randomized to receive sildenafil 100 mg or placebo on two experimental days, each separated by at least one week, between days 8 and 21. The primary endpoint was the difference in the incidence of migraine attacks between sildenafil and placebo during the 12-h observation period after administration. RESULTS In total, 16 participants completed the study. Ten participants (63%) experienced a migraine attack within 12 h after sildenafil administration compared to three (19%) after placebo (p = 0.016). The median headache intensity was higher after sildenafil than after placebo (area under the curve (AUC) for the 12-h observation period, p = 0.026). Furthermore, sildenafil induced a significant decrease in mean arterial blood pressure (AUC, p = 0.026) and a simultaneous increase in heart rate (AUC, p < 0.001) during the first hour after administration compared to placebo. CONCLUSION These findings provide evidence that migraine induction via the cGMP pathway can occur even under CGRP receptor blockade. TRIAL REGISTRATION ClinicalTrials.gov: Identifier NCT05889455.
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Affiliation(s)
- Bianca Raffaelli
- Department of Neurology, Danish Headache Center, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
- Department of Neurology, Charité Universitätsmedizin Berlin, Berlin, Germany
- Clinician Scientist Program, Berlin Institute of Health at Charité (BIH), Berlin, Germany
| | - Thien Phu Do
- Department of Neurology, Danish Headache Center, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Håkan Ashina
- Department of Neurology, Danish Headache Center, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
- Translational Research Center, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
| | | | | | - Messoud Ashina
- Department of Neurology, Danish Headache Center, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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2
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Kalyani P, Lippa SM, Werner JK, Amyot F, Moore CB, Kenney K, Diaz-Arrastia R. Phosphodiesterase-5 (PDE-5) Inhibitors as Therapy for Cerebrovascular Dysfunction in Chronic Traumatic Brain Injury. Neurotherapeutics 2023; 20:1629-1640. [PMID: 37697134 PMCID: PMC10684467 DOI: 10.1007/s13311-023-01430-z] [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] [Accepted: 08/22/2023] [Indexed: 09/13/2023] Open
Abstract
Multiple phase III randomized controlled trials (RCTs) for pharmacologic interventions in traumatic brain injury (TBI) have failed despite promising results in experimental models. The heterogeneity of TBI, in terms of pathomechanisms and impacted brain structures, likely contributes to these failures. Biomarkers have been recommended to identify patients with relevant pathology (predictive biomarkers) and confirm target engagement and monitor therapy response (pharmacodynamic biomarkers). Our group focuses on traumatic cerebrovascular injury as an understudied endophenotype of TBI and is validating a predictive and pharmacodynamic imaging biomarker (cerebrovascular reactivity; CVR) in moderate-severe TBI. We aim to extend these studies to milder forms of TBI to determine the optimal dose of sildenafil for maximal improvement in CVR. We will conduct a phase II dose-finding study involving 160 chronic TBI patients (mostly mild) using three doses of sildenafil, a phosphodiesterase-5 (PDE-5) inhibitor. The study measures baseline CVR and evaluates the effect of escalating sildenafil doses on CVR improvement. A 4-week trial of thrice daily sildenafil will assess safety, tolerability, and clinical efficacy. This dual-site 4-year study, funded by the Department of Defense and registered in ClinicalTrials.gov (NCT05782244), plans to launch in June 2023. Biomarker-informed RCTs are essential for developing effective TBI interventions, relying on an understanding of underlying pathomechanisms. Traumatic microvascular injury (TMVI) is an attractive mechanism which can be targeted by vaso-active drugs such as PDE-5 inhibitors. CVR is a potential predictive and pharmacodynamic biomarker for targeted interventions aimed at TMVI. (Trial registration: NCT05782244, ClinicalTrials.gov ).
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Affiliation(s)
- Priyanka Kalyani
- Department of Neurology, University of Pennsylvania, 3400 Spruce St, Philadelphia, PA, 19104, USA.
| | - Sara M Lippa
- Walter Reed National Military Medical Center, The National Intrepid Center of Excellence, Palmer Rd S, Bethesda, MD, 20814, USA
- Department of Neuroscience, Uniformed Services University Health Sciences, 4301, Jones Bridge Rd, Bethesda, MD, 20814, USA
| | - J Kent Werner
- Walter Reed National Military Medical Center, The National Intrepid Center of Excellence, Palmer Rd S, Bethesda, MD, 20814, USA
- Department of Neuroscience, Uniformed Services University Health Sciences, 4301, Jones Bridge Rd, Bethesda, MD, 20814, USA
| | - Franck Amyot
- Walter Reed National Military Medical Center, The National Intrepid Center of Excellence, Palmer Rd S, Bethesda, MD, 20814, USA
| | - Carol B Moore
- Department of Neuroscience, Uniformed Services University Health Sciences, 4301, Jones Bridge Rd, Bethesda, MD, 20814, USA
| | - Kimbra Kenney
- Department of Neuroscience, Uniformed Services University Health Sciences, 4301, Jones Bridge Rd, Bethesda, MD, 20814, USA
| | - Ramon Diaz-Arrastia
- Department of Neurology, University of Pennsylvania, 3400 Spruce St, Philadelphia, PA, 19104, USA
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3
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Carr JMJR, Hoiland RL, Fernandes IA, Schrage WG, Ainslie PN. Recent insights into mechanisms of hypoxia-induced vasodilatation in the human brain. J Physiol 2023. [PMID: 37655827 DOI: 10.1113/jp284608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 08/07/2023] [Indexed: 09/02/2023] Open
Abstract
The cerebral vasculature manages oxygen delivery by adjusting arterial blood in-flow in the face of reductions in oxygen availability. Hypoxic cerebral vasodilatation, and the associated hypoxic cerebral blood flow reactivity, involve many vascular, erythrocytic and cerebral tissue mechanisms that mediate elevations in cerebral blood flow via micro- and macrovascular dilatation. This contemporary review focuses on in vivo human work - with reference to seminal preclinical work where necessary - on hypoxic cerebrovascular reactivity, particularly where recent advancements have been made. We provide updates with the following information: in humans, hypoxic cerebral vasodilatation is partially mediated via a - likely non-obligatory - combination of: (1) nitric oxide synthases, (2) deoxygenation-coupled S-nitrosothiols, (3) potassium channel-related vascular smooth muscle hyperpolarization, and (4) prostaglandin mechanisms with some contribution from an interrelationship with reactive oxygen species. And finally, we discuss the fact that, due to the engagement of deoxyhaemoglobin-related mechanisms, reductions in O2 content via haemoglobin per se seem to account for ∼50% of that seen with hypoxic cerebral vasodilatation during hypoxaemia. We further highlight the issue that methodological impediments challenge the complete elucidation of hypoxic cerebral reactivity mechanisms in vivo in healthy humans. Future research is needed to confirm recent advancements and to reconcile human and animal findings. Further investigations are also required to extend these findings to address questions of sex-, heredity-, age-, and disease-related differences. The final step is to then ultimately translate understanding of these mechanisms into actionable, targetable pathways for the prevention and treatment of cerebral vascular dysfunction and cerebral hypoxic brain injury.
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Affiliation(s)
- Jay M J R Carr
- Centre for Heart, Lung and Vascular Health, University of British Columbia Okanagan, Kelowna, British Columbia, Canada
| | - Ryan L Hoiland
- Department of Anesthesiology, Pharmacology and Therapeutics, Vancouver General Hospital, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, British Columbia, Canada
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
- Collaborative Entity for Researching Brain Ischemia (CEREBRI), University of British Columbia, Vancouver, British Columbia, Canada
| | - Igor A Fernandes
- Department of Health and Kinesiology, Purdue University, Indiana, USA
| | - William G Schrage
- Department of Kinesiology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Philip N Ainslie
- Centre for Heart, Lung and Vascular Health, University of British Columbia Okanagan, Kelowna, British Columbia, Canada
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4
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Hainsworth AH, Arancio O, Elahi FM, Isaacs JD, Cheng F. PDE5 inhibitor drugs for use in dementia. ALZHEIMER'S & DEMENTIA (NEW YORK, N. Y.) 2023; 9:e12412. [PMID: 37766832 PMCID: PMC10520293 DOI: 10.1002/trc2.12412] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 07/07/2023] [Accepted: 07/08/2023] [Indexed: 09/29/2023]
Abstract
Alzheimer's disease and related dementias (ADRD) remain a major health-care challenge with few licensed medications. Repurposing existing drugs may afford prevention and treatment. Phosphodiesterase-5 (PDE5) is widely expressed in vascular myocytes, neurons, and glia. Potent, selective, Food and Drug Administration-approved PDE5 inhibitors are already in clinical use (sildenafil, vardenafil, tadalafil) as vasodilators in erectile dysfunction and pulmonary arterial hypertension. Animal data indicate cognitive benefits of PDE5 inhibitors. In humans, real-world patient data suggest that sildenafil and vardenafil are associated with reduced dementia risk. While a recent clinical trial of acute tadalafil on cerebral blood flow was neutral, there may be chronic actions of PDE5 inhibition on cerebrovascular or synaptic function. We provide a perspective on the potential utility of PDE5 inhibitors for ADRD. We conclude that further prospective clinical trials with PDE5 inhibitors are warranted. The choice of drug will depend on brain penetration, tolerability in older people, half-life, and off-target effects. HIGHLIGHTS Potent phosphodiesterase-5 (PDE5) inhibitors are in clinical use as vasodilators.In animals PDE5 inhibitors enhance synaptic function and cognitive ability.In humans the PDE5 inhibitor sildenafil is associated with reduced risk of Alzheimer's disease.Licensed PDE5 inhibitors have potential for repurposing in dementia.Prospective clinical trials of PDE5 inhibitors are warranted.
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Affiliation(s)
- Atticus H. Hainsworth
- Molecular & Clinical Sciences Research InstituteSt George's University of LondonLondonUK
- Department of NeurologySt George's University Hospitals NHS Foundation TrustLondonUK
| | - Ottavio Arancio
- Department of Pathology and Cell BiologyTaub Institute for Research on Alzheimer's Disease and the Aging BrainDepartment of MedicineColumbia UniversityNew YorkNew YorkUSA
| | - Fanny M. Elahi
- Departments of Neurology and NeuroscienceRonald M. Loeb Center for Alzheimer's DiseaseFriedman Brain InstituteIcahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
| | - Jeremy D. Isaacs
- Molecular & Clinical Sciences Research InstituteSt George's University of LondonLondonUK
- Department of NeurologySt George's University Hospitals NHS Foundation TrustLondonUK
| | - Feixiong Cheng
- Genomic Medicine InstituteLerner Research InstituteCleveland ClinicClevelandOhioUSA
- Department of Molecular MedicineCleveland Clinic Lerner College of MedicineCase Western Reserve UniversityClevelandOhioUSA
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5
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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.
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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
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6
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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.
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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
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7
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Ölmestig J, Marlet IR, Hansen RH, Rehman S, Krawcyk RS, Rostrup E, Lambertsen KL, Kruuse C. Tadalafil may improve cerebral perfusion in small-vessel occlusion stroke-a pilot study. Brain Commun 2020; 2:fcaa020. [PMID: 33033800 PMCID: PMC7530832 DOI: 10.1093/braincomms/fcaa020] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 12/22/2019] [Accepted: 12/28/2019] [Indexed: 01/29/2023] Open
Abstract
New treatments for cerebral small-vessel disease are needed to reduce the risk of small-vessel occlusion stroke and vascular cognitive impairment. We investigated an approach targeted to the signalling molecule cyclic guanosine monophosphate, using the phosphodiesterase 5 inhibitor tadalafil, to explore if it improves cerebral blood flow and endothelial function in patients with cerebral small-vessel disease and stroke. In a randomized, double-blinded, placebo-controlled, cross-over pilot trial (NCT02801032), we included patients who had a previous (>6 months) small-vessel occlusion stroke. They received a single dose of either 20 mg tadalafil or placebo on 2 separate days at least 1 week apart. We measured the following: baseline MRI for lesion load, repeated measurements of blood flow velocity in the middle cerebral artery by transcranial Doppler, blood oxygen saturation in the cortical microvasculature by near-infrared spectroscopy, peripheral endothelial response by EndoPAT and endothelial-specific blood biomarkers. Twenty patients with cerebral small-vessel disease stroke (3 women, 17 men), mean age 67.1 ± 9.6, were included. The baseline mean values ± standard deviations were as follows: blood flow velocity in the middle cerebral artery, 57.4 ± 10.8 cm/s; blood oxygen saturation in the cortical microvasculature, 67.0 ± 8.2%; systolic blood pressure, 145.8 ± 19.5 mmHg; and diastolic blood pressure, 81.3 ± 9.1 mmHg. We found that tadalafil significantly increased blood oxygen saturation in the cortical microvasculature at 180 min post-administration with a mean difference of 1.57 ± 3.02%. However, we saw no significant differences in transcranial Doppler measurements over time. Tadalafil had no effects on peripheral endothelial function assessed by EndoPAT and endothelial biomarker results conflicted. Our findings suggest that tadalafil may improve vascular parameters in patients with cerebral small-vessel disease stroke, although the effect size was small. Increased oxygenation of cerebral microvasculature during tadalafil treatment indicated improved perfusion in the cerebral microvasculature, theoretically presenting an attractive new therapeutic target in cerebral small-vessel disease. Future studies of the effect of long-term tadalafil treatment on cerebrovascular reactivity and endothelial function are needed to evaluate general microvascular changes and effects in cerebral small-vessel disease and stroke.
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Affiliation(s)
- Joakim Ölmestig
- Department of Neurology, Neurovascular Research Unit, Herlev Gentofte Hospital, University of Copenhagen, Herlev 2730, Denmark
| | - Ida R Marlet
- Department of Neurology, Neurovascular Research Unit, Herlev Gentofte Hospital, University of Copenhagen, Herlev 2730, Denmark
| | - Rasmus H Hansen
- Department of Radiology, Herlev Gentofte Hospital, Herlev 2730, Denmark
| | - Shazia Rehman
- Department of Radiology, Herlev Gentofte Hospital, Herlev 2730, Denmark
| | - Rikke Steen Krawcyk
- Department of Neurology, Neurovascular Research Unit, Herlev Gentofte Hospital, University of Copenhagen, Herlev 2730, Denmark.,Department of Physiotherapy and Occupational Therapy, Herlev Gentofte Hospital, Herlev 2730, Denmark
| | - Egill Rostrup
- Center for Neuropsychiatric Schizophrenia Research, Mental Health Center Glostrup, Capital Region Psychiatry, Glostrup 2600, Denmark
| | - Kate L Lambertsen
- Department of Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Odense 5000, Denmark.,Department of Neurology, Odense University Hospital, Odense 5000, Denmark.,BRIDGE-Brain Research Inter-Disciplinary Guided Excellence, Department of Clinical Research, University of Southern Denmark, Odense 5000, Denmark
| | - Christina Kruuse
- Department of Neurology, Neurovascular Research Unit, Herlev Gentofte Hospital, University of Copenhagen, Herlev 2730, Denmark.,Institute for Clinical Medicine, University of Copenhagen, 2200 Copenhagen N, Denmark
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8
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Zuccarello E, Acquarone E, Calcagno E, Argyrousi EK, Deng SX, Landry DW, Arancio O, Fiorito J. Development of novel phosphodiesterase 5 inhibitors for the therapy of Alzheimer's disease. Biochem Pharmacol 2020; 176:113818. [PMID: 31978378 DOI: 10.1016/j.bcp.2020.113818] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 01/14/2020] [Indexed: 12/13/2022]
Abstract
Nitric oxide (NO) is a gaseous molecule that plays a multifactorial role in several cellular processes. In the central nervous system, the NO dual nature in neuroprotection and neurotoxicity has been explored to unveil its involvement in Alzheimer's disease (AD). A growing body of research shows that the activation of the NO signaling pathway leading to the phosphorylation of the transcription factor cyclic adenine monophosphate responsive element binding protein (CREB) (so-called NO/cGMP/PKG/CREB signaling pathway) ameliorates altered neuroplasticity and memory deficits in AD animal models. In addition to NO donors, several other pharmacological agents, such as phosphodiesterase 5 (PDE5) inhibitors have been used to activate the pathway and rescue memory disorders. PDE5 inhibitors, including sildenafil, tadalafil and vardenafil, are marketed for the treatment of erectile dysfunction and arterial pulmonary hypertension due to their vasodilatory properties. The ability of PDE5 inhibitors to interfere with the NO/cGMP/PKG/CREB signaling pathway by increasing the levels of cGMP has prompted the hypothesis that PDE5 inhibition might be used as an effective therapeutic strategy for the treatment of AD. To this end, newly designed PDE5 inhibitors belonging to different chemical classes with improved pharmacologic profile (e.g. higher potency, improved selectivity, and blood-brain barrier penetration) have been synthesized and evaluated in several animal models of AD. In addition, recent medicinal chemistry effort has led to the development of agents concurrently acting on the PDE5 enzyme and a second target involved in AD. Both marketed and investigational PDE5 inhibitors have shown to reverse cognitive defects in young and aged wild type mice as well as transgenic mouse models of AD and tauopathy using a variety of behavioral tasks. These studies confirmed the therapeutic potential of PDE5 inhibitors as cognitive enhancers. However, clinical studies assessing cognitive functions using marketed PDE5 inhibitors have not been conclusive. Drug discovery efforts by our group and others are currently directed towards the development of novel PDE5 inhibitors tailored to AD with improved pharmacodynamic and pharmacokinetic properties. In summary, the present perspective reports an overview of the correlation between the NO signaling and AD, as well as an outline of the PDE5 inhibitors used as an alternative approach in altering the NO pathway leading to an improvement of learning and memory. The last two sections describe the preclinical and clinical evaluation of PDE5 inhibitors for the treatment of AD, providing a comprehensive analysis of the current status of the AD drug discovery efforts involving PDE5 as a new therapeutic target.
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Affiliation(s)
- Elisa Zuccarello
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, NY, United States
| | - Erica Acquarone
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, NY, United States
| | - Elisa Calcagno
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, NY, United States
| | - Elentina K Argyrousi
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, NY, United States
| | - Shi-Xian Deng
- Department of Medicine, Columbia University, New York, NY, United States
| | - Donald W Landry
- Department of Medicine, Columbia University, New York, NY, United States
| | - Ottavio Arancio
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, NY, United States; Department of Medicine, Columbia University, New York, NY, United States; Department of Pathology and Cell Biology, Columbia University, New York, NY, United States.
| | - Jole Fiorito
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, NY, United States; Department of Biological and Chemical Sciences, New York Institute of Technology, Old Westbury, NY, United States.
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9
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Arngrim N, Hougaard A, Schytz HW, Vestergaard MB, Britze J, Amin FM, Olsen KS, Larsson HB, Olesen J, Ashina M. Effect of hypoxia on BOLD fMRI response and total cerebral blood flow in migraine with aura patients. J Cereb Blood Flow Metab 2019; 39:680-689. [PMID: 28686073 PMCID: PMC6446416 DOI: 10.1177/0271678x17719430] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Experimentally induced hypoxia triggers migraine and aura attacks in patients suffering from migraine with aura (MA). We investigated the blood oxygenation level-dependent (BOLD) signal response to visual stimulation during hypoxia in MA patients and healthy volunteers. In a randomized double-blind crossover study design, 15 MA patients were allocated to 180 min of normobaric poikilocapnic hypoxia (capillary oxygen saturation 70-75%) or sham (normoxia) on two separate days and 14 healthy volunteers were exposed to hypoxia. The BOLD functional MRI (fMRI) signal response to visual stimulation was measured in the visual cortex ROIs V1-V5. Total cerebral blood flow (CBF) was calculated by measuring the blood velocity in the internal carotid arteries and the basilar artery using phase-contrast mapping (PCM) MRI. Hypoxia induced a greater decrease in BOLD response to visual stimulation in V1-V4 in MA patients compared to controls. There was no group difference in hypoxia-induced total CBF increase. In conclusion, the study demonstrated a greater hypoxia-induced decrease in BOLD response to visual stimulation in MA patients. We suggest this may represent a hypoxia-induced change in neuronal excitability or abnormal vascular response to visual stimulation, which may explain the increased sensibility to hypoxia in these patients leading to migraine attacks.
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Affiliation(s)
- Nanna Arngrim
- 1 Danish Headache Center and Department of Neurology, University of Copenhagen, Copenhagen, Denmark
| | - Anders Hougaard
- 1 Danish Headache Center and Department of Neurology, University of Copenhagen, Copenhagen, Denmark
| | - Henrik W Schytz
- 1 Danish Headache Center and Department of Neurology, University of Copenhagen, Copenhagen, Denmark
| | - Mark B Vestergaard
- 2 Department of Clinical Physiology, Nuclear Medicine and PET, Functional Imaging Unit, University of Copenhagen, Copenhagen, Denmark
| | - Josefine Britze
- 1 Danish Headache Center and Department of Neurology, University of Copenhagen, Copenhagen, Denmark
| | - Faisal Mohammad Amin
- 1 Danish Headache Center and Department of Neurology, University of Copenhagen, Copenhagen, Denmark
| | - Karsten S Olsen
- 3 Department of Neuroanaesthesiology, The Neuroscience Centre, Rigshospitalet Glostrup, Faculty of Health and Medical Sciences, University of Copenhagen, Glostrup, Denmark
| | - Henrik Bw Larsson
- 2 Department of Clinical Physiology, Nuclear Medicine and PET, Functional Imaging Unit, University of Copenhagen, Copenhagen, Denmark
| | - Jes Olesen
- 1 Danish Headache Center and Department of Neurology, University of Copenhagen, Copenhagen, Denmark
| | - Messoud Ashina
- 1 Danish Headache Center and Department of Neurology, University of Copenhagen, Copenhagen, Denmark
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10
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Sheng M, Lu H, Liu P, Li Y, Ravi H, Peng SL, Diaz-Arrastia R, Devous MD, Womack KB. Sildenafil Improves Vascular and Metabolic Function in Patients with Alzheimer's Disease. J Alzheimers Dis 2018; 60:1351-1364. [PMID: 29036811 DOI: 10.3233/jad-161006] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND Alzheimer's disease (AD) is the leading cause of degenerative dementia in the aging population. Patients with AD have alterations in cerebral hemodynamic function including reduced cerebral blood flow (CBF) and cerebral metabolic rate. Therefore, improved cerebrovascular function may be an attractive goal for pharmaceutical intervention in AD. OBJECTIVE We wished to observe the acute effects of sildenafil on cerebrovascular function and brain metabolism in patients with AD. METHODS We used several novel non-invasive MRI techniques to investigate the alterations of CBF, cerebral metabolic rate of oxygen (CMRO2), and cerebrovascular reactivity (CVR) after a single dose of sildenafil administration in order to assess its physiological effects in patients with AD. CBF, CMRO2, and CVR measurements using MRI were performed before and one hour after the oral administration of 50 mg sildenafil. Baseline Montreal Cognitive Assessment score was also obtained. RESULTS Complete CBF and CMRO2 data were obtained in twelve patients. Complete CVR data were obtained in eight patients. Global CBF and CMRO2 significantly increased (p = 0.03, p = 0.05, respectively) following sildenafil administration. Voxel-wise analyses of CBF maps showed that increased CBF was most pronounced in the bilateral medial temporal lobes. CVR significantly decreased after administration of sildenafil. CONCLUSION Our data suggest that a single dose of sildenafil improves cerebral hemodynamic function and increases cerebral oxygen metabolism in patients with AD.
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Affiliation(s)
- Min Sheng
- Advanced Imaging Research Center, The University of Texas Southwestern Medical Center, Dallas, TX, USA.,Department of Radiology, Beijing Eden Hospital, Beijing, China
| | - Hanzhang Lu
- Advanced Imaging Research Center, The University of Texas Southwestern Medical Center, Dallas, TX, USA.,Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Peiying Liu
- Advanced Imaging Research Center, The University of Texas Southwestern Medical Center, Dallas, TX, USA.,Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Yang Li
- Advanced Imaging Research Center, The University of Texas Southwestern Medical Center, Dallas, TX, USA.,Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Harshan Ravi
- Advanced Imaging Research Center, The University of Texas Southwestern Medical Center, Dallas, TX, USA.,Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Shin-Lei Peng
- Advanced Imaging Research Center, The University of Texas Southwestern Medical Center, Dallas, TX, USA.,Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan
| | - Ramon Diaz-Arrastia
- Department of Neurology, University of Pennsylvania Perelman School of Medicine, Penn Presbyterian Medical Center, Philadelphia, PA, USA
| | - Michael D Devous
- Department of Neurology and Neurotherapeutics, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Kyle B Womack
- Department of Neurology and Neurotherapeutics, The University of Texas Southwestern Medical Center, Dallas, TX, USA.,Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, TX, USA
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11
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Younis S, Hougaard A, Christensen CE, Vestergaard MB, Petersen ET, Paulson OB, Larsson HBW, Ashina M. Effects of sildenafil and calcitonin gene-related peptide on brainstem glutamate levels: a pharmacological proton magnetic resonance spectroscopy study at 3.0 T. J Headache Pain 2018; 19:44. [PMID: 29916084 PMCID: PMC6005999 DOI: 10.1186/s10194-018-0870-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 06/07/2018] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Studies involving human pharmacological migraine models have predominantly focused on the vasoactive effects of headache-inducing drugs, including sildenafil and calcitonin gene-related peptide (CGRP). However, the role of possible glutamate level changes in the brainstem and thalamus is of emerging interest in the field of migraine research bringing forth the need for a novel, validated method to study the biochemical effects in these areas. METHODS We applied an optimized in vivo human pharmacological proton (1H) magnetic resonance spectroscopy (MRS) protocol (PRESS, repetition time 3000 ms, echo time 37.6-38.3 ms) at 3.0 T in combination with sildenafil and CGRP in a double-blind, placebo-controlled, randomized, double-dummy, three-way cross-over design. Seventeen healthy participants were scanned with the 1H-MRS protocol at baseline and twice (at 40 min and 140 min) after drug administration to investigate the sildenafil- and CGRP-induced glutamate changes in both brainstem and thalamus. RESULTS The glutamate levels increased transiently in the brainstem at 40-70 min after sildenafil administration compared to placebo (5.6%, P = 0.039). We found no sildenafil-induced glutamate changes in the thalamus, and no CGRP-induced glutamate changes in the brainstem or thalamus compared to placebo. Both sildenafil and CGRP induced headache in 53%-62% of participants. We found no interaction in the glutamate levels in the brainstem or thalamus between participants who developed sildenafil and/or CGRP-induced headache as compared to participants who did not. CONCLUSIONS The transient sildenafil-induced glutamate change in the brainstem possibly reflects increased excitability of the brainstem neurons. CGRP did not induce brainstem or thalamic glutamate changes, suggesting that it rather exerts its headache-inducing effects on the peripheral trigeminal pain pathways.
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Affiliation(s)
- Samaira Younis
- Danish Headache Center, Department of Neurology, Rigshospitalet Glostrup, University of Copenhagen, Copenhagen, Denmark
| | - Anders Hougaard
- Danish Headache Center, Department of Neurology, Rigshospitalet Glostrup, University of Copenhagen, Copenhagen, Denmark
| | - Casper Emil Christensen
- Danish Headache Center, Department of Neurology, Rigshospitalet Glostrup, University of Copenhagen, Copenhagen, Denmark
| | - Mark Bitsch Vestergaard
- Functional Imaging Unit, Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet Glostrup, University of Copenhagen, Copenhagen, Denmark
| | - Esben Thade Petersen
- Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and research, Copenhagen University Hospital Hvidovre, Copenhagen, Denmark
| | - Olaf Bjarne Paulson
- Neurobiology Research Unit, Department of Neurology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Henrik Bo Wiberg Larsson
- Functional Imaging Unit, Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet Glostrup, University of Copenhagen, Copenhagen, Denmark
| | - Messoud Ashina
- Danish Headache Center, Department of Neurology, Rigshospitalet Glostrup, University of Copenhagen, Copenhagen, Denmark.
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12
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Heckman PRA, Blokland A, Bollen EPP, Prickaerts J. Phosphodiesterase inhibition and modulation of corticostriatal and hippocampal circuits: Clinical overview and translational considerations. Neurosci Biobehav Rev 2018; 87:233-254. [PMID: 29454746 DOI: 10.1016/j.neubiorev.2018.02.007] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 02/07/2018] [Accepted: 02/09/2018] [Indexed: 12/20/2022]
Abstract
The corticostriatal and hippocampal circuits contribute to the neurobiological underpinnings of several neuropsychiatric disorders, including Alzheimer's disease, Parkinson's disease and schizophrenia. Based on biological function, these circuits can be clustered into motor circuits, associative/cognitive circuits and limbic circuits. Together, dysfunctions in these circuits produce the wide range of symptoms observed in related neuropsychiatric disorders. Intracellular signaling in these circuits is largely mediated through the cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) pathway with an additional role for the cyclic guanosine monophosphate (cGMP)/ protein kinase G (PKG) pathway, both of which can be regulated by phosphodiesterase inhibitors (PDE inhibitors). Through their effects on cAMP response element-binding protein (CREB) and Dopamine- and cAMP-Regulated PhosphoProtein MR 32 kDa (DARPP-32), cyclic nucleotide pathways are involved in synaptic transmission, neuron excitability, neuroplasticity and neuroprotection. In this clinical review, we provide an overview of the current clinical status, discuss the general mechanism of action of PDE inhibitors in relation to the corticostriatal and hippocampal circuits and consider several translational challenges.
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Affiliation(s)
- P R A Heckman
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands; Department of Neuropsychology and Psychopharmacology, Maastricht University, Maastricht, The Netherlands.
| | - A Blokland
- Department of Neuropsychology and Psychopharmacology, Maastricht University, Maastricht, The Netherlands
| | - E P P Bollen
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - J Prickaerts
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
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13
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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).
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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
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14
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Jahshan S, Dayan L, Jacob G. Nitric oxide-sensitive guanylyl cyclase signaling affects CO2-dependent but not pressure-dependent regulation of cerebral blood flow. Am J Physiol Regul Integr Comp Physiol 2017; 312:R948-R955. [DOI: 10.1152/ajpregu.00241.2016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 03/27/2017] [Accepted: 03/27/2017] [Indexed: 01/06/2023]
Abstract
Cerebrovascular CO2 reactivity is affected by nitric oxide (NO). We tested the hypothesis that sildenafil selectively potentiates NO-cGMP signaling, which affects CO2 reactivity. Fourteen healthy males (34 ± 2 yr) were enrolled in the study. Blood pressure (BP), ECG, velocity of cerebral blood flow (CBF; measured by transcranial Doppler), and end-tidal CO2 (EtCO2) were assessed at baseline (CO2 ~39 mmHg), during hyperventilation (CO2 ~24 mmHg), during hypercapnia (CO2 ~46 mmHg), during boluses of phenylephrine (25–200 µg), and during graded head-up tilting (HUT). Measurements were repeated 1 h after 100 mg sildenafil were taken. Results showed that sildenafil did not affect resting BP, heart rate, CBF peak and mean velocities, estimated regional cerebrovascular resistance (eCVR; mean BP/mean CBF), breath/min, and EtCO2: 117 ± 2/67 ± 3 mmHg, 69 ± 3 beats/min, 84 ± 5 and 57 ± 4 cm/s, 1.56 ± 0.1 mmHg·cm−1·s−1, 14 ± 0.5 breaths/min, and 39 ± 0.9 mmHg, respectively. Sildenafil increased and decreased the hypercapnia induced in CBF and eCVR, respectively. Sildenafil also attenuated the decrease in peak velocity of CBF, 25 ± 2 vs. 20 ± 2% ( P < 0.05) and increased the eCVR, 2.5 ± 0.2 vs. 2 ± 0.2% ( P < 0.03) during hyperventilation. Sildenafil did not affect CBF despite significant increases in the eCVRs that were elicited by phenylephrine and HUT. This investigation suggests that sildenafil, which potentiates the NO-cGMP signaling, seems to affect the cerebrovascular CO2 reactivity without affecting the static and dynamic pressure-dependent mechanisms of cerebrovascular autoregulation.
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Affiliation(s)
- Shadi Jahshan
- J. Recanati Autonomic Dysfunction Center, Tel Aviv “Sourasky” Medical Center, Tel Aviv University, Tel Aviv, Israel
- Neurosurgery Department, Tel Aviv “Sourasky” Medical Center, Tel Aviv University, Tel Aviv, Israel; and
| | - Lior Dayan
- J. Recanati Autonomic Dysfunction Center, Tel Aviv “Sourasky” Medical Center, Tel Aviv University, Tel Aviv, Israel
| | - Giris Jacob
- Department of Internal Medicine, Tel Aviv “Sourasky” Medical Center, Tel Aviv University, Tel Aviv, Israel
- J. Recanati Autonomic Dysfunction Center, Tel Aviv “Sourasky” Medical Center, Tel Aviv University, Tel Aviv, Israel
- Faculty of Medicine, Tel Aviv “Sourasky” Medical Center, Tel Aviv University, Tel Aviv, Israel
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15
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Lindberg U, Witting N, Jørgensen SL, Vissing J, Rostrup E, Larsson HBW, Kruuse C. Effects of Sildenafil on Cerebrovascular Reactivity in Patients with Becker Muscular Dystrophy. Neurotherapeutics 2017; 14:182-190. [PMID: 27485237 PMCID: PMC5233618 DOI: 10.1007/s13311-016-0467-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Patients suffering from Becker muscular dystrophy (BMD) have dysfunctional dystrophin proteins and are deficient in neuronal nitric oxide synthase (nNOS) in muscles. This causes functional ischemia and contributes to muscle wasting. Similar functional ischemia may be present in brains of patients with BMD, who often have mild cognitive impairment, and nNOS may be important for the regulation of the microvascular circulation in the brain. We hypothesized that treatment with sildenafil, a phosphodiesterase type 5 inhibitor that potentiates nitric oxide responses, would augment both the blood oxygen level-dependent (BOLD) response and cerebral blood flow (CBF) in patients with BMD. Seventeen patients (mean ± SD age 38.5 ± 10.8 years) with BMD were included in this randomized, double-blind, placebo-controlled, crossover trial. Twelve patients completed the entire study. Effects of sildenafil were assessed by 3 T magnetic resonance (MR) scanning, evoked potentials, somatosensory task-induced BOLD functional MR imaging, regional and global perfusion, and angiography before and after 4 weeks of sildenafil, 20 mg (Revatio in gelatine capsules, oral, 3 times daily), or placebo treatment. Sildenafil increased the event-related sensory and visual BOLD response compared with placebo (p < 0.01). However, sildenafil did not alter CBF, measured by MR phase contrast mapping, or the arterial diameter of the middle cerebral artery, measured by MR angiography. We conclude that nNOS may play a role in event-related neurovascular responses. Further studies in patients with BMD may help clarify the roles of dystrophin and nNOS in neurovascular coupling in general, and in patients with BMD in particular.
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Affiliation(s)
- Ulrich Lindberg
- Functional Imaging Unit, Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet Glostrup, University of Copenhagen, Glostrup, Denmark
- Lundbeck Foundation Center for Neurovascular signalling (LUCENS), Rigshospitalet Glostrup, University of Copenhagen, Glostrup, Denmark
| | - Nanna Witting
- Copenhagen Neuromuscular Center and Department of Neurology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Stine Lundgaard Jørgensen
- Lundbeck Foundation Center for Neurovascular signalling (LUCENS), Rigshospitalet Glostrup, University of Copenhagen, Glostrup, Denmark
| | - John Vissing
- Copenhagen Neuromuscular Center and Department of Neurology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Egill Rostrup
- Functional Imaging Unit, Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet Glostrup, University of Copenhagen, Glostrup, Denmark
| | - Henrik Bo Wiberg Larsson
- Functional Imaging Unit, Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet Glostrup, University of Copenhagen, Glostrup, Denmark
- Lundbeck Foundation Center for Neurovascular signalling (LUCENS), Rigshospitalet Glostrup, University of Copenhagen, Glostrup, Denmark
| | - Christina Kruuse
- Lundbeck Foundation Center for Neurovascular signalling (LUCENS), Rigshospitalet Glostrup, University of Copenhagen, Glostrup, Denmark.
- Neurovascular Research Unit, Department of Neurology, Herlev Gentofte Hospital, University of Copenhagen, Herlev, Denmark.
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16
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Katusic ZS, Austin SA. Neurovascular Protective Function of Endothelial Nitric Oxide - Recent Advances. Circ J 2016; 80:1499-503. [PMID: 27238834 DOI: 10.1253/circj.cj-16-0423] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In the central nervous system endothelial nitric oxide (NO) is an essential molecule responsible for the preservation of the functional integrity of the neurovascular unit. NO causes vasodilatation and is an important inhibitor of platelet aggregation, smooth muscle cell proliferation, and white blood cell adhesion. In addition, endothelium-derived NO exerts anti-inflammatory and pro-angiogenic effects. More recently, it has been recognized that endothelial NO modulates the expression and processing of amyloid precursor protein in cerebrovascular endothelium and neuronal tissue. Studies in endothelial NO synthase (eNOS) knockout mice indicate that endothelial NO functions as a neurovascular protective molecule during aging. Indeed, genetic inactivation of eNOS exacerbates the detrimental effects of aging on cerebrovascular, microglial, and neuronal functions as well as on cognition. These findings suggest that the preservation of healthy endothelium and normal function of eNOS might be important therapeutic targets. Because the beneficial effects of NO are mostly mediated by the activation of guanylate cyclase/cyclic GMP signaling, inhibitors of phosphodiesterase isoforms, or activation of this signaling with exercise, may offer therapeutic opportunities in the prevention and treatment of aging-induced cognitive decline and Alzheimer's disease. Most recent advances in understanding the molecular mechanisms linking loss of endothelial NO with cognitive decline will be discussed in this review. (Circ J 2016; 80: 1499-1503).
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Affiliation(s)
- Zvonimir S Katusic
- Department of Anesthesiology and Molecular Pharmacology & Experimental Therapeutics, Mayo Clinic
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17
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Effects of daily low-dose treatment with phosphodiesterase type 5 inhibitor on cognition, depression, somatization and erectile function in patients with erectile dysfunction: a double-blind, placebo-controlled study. Int J Impot Res 2013; 26:76-80. [PMID: 24285284 DOI: 10.1038/ijir.2013.38] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Revised: 08/29/2013] [Accepted: 10/21/2013] [Indexed: 01/09/2023]
Abstract
Phosphodiesterase type 5 (PDE5) inhibitors have recently been shown to have cognitive-enhancing effects in animal models and in our previous pilot study. To investigate the efficacy of daily low-dose treatment with a PDE5 inhibitor on cognitive function, depression and somatization in patients with erectile dysfunction (ED), 8-week, double-blind, placebo-controlled study enrolled 60 male patients with ED for ≥ 3 months without cognitive impairment. Forty-nine patients completed the study. Patients were randomized to receive either daily low-dose udenafil 50 mg or placebo for 2 months. The International Index of Erectile Function-5 (IIEF-5), the Korean version of the Mini-Mental State Examination (K-MMSE) for general cognitive function and the Seoul Neuropsychological Screening Battery for comprehensive neuropsychological examination, the Physical Health Questionnaire-9 (PHQ-9) for depression and the Physical Health Questionnaire-15 (PHQ-15) for somatization were administered at baseline and at 2 months. The change in the mean IIEF-5 was significantly higher in the udenafil group than the placebo group (6.08 ± 4.72 vs 2.20 ± 3.50, P=0.008). The changes in the PHQ-9 and PHQ-15 were -2.04 ± 3.14 and -2.17 ± 2.87 in the udenafil group, and 1.20 ± 1.63 and 0.56 ± 2.48 in the placebo group (both, P<0.001). The changes in the K-MMSE and Digit Span Forward were 1.25 ± 1.26 and 0.92 ± 1.02 in the udenafil group, and -0.52 ± 1.19 and -0.24 ± 1.13 in the placebo group (both, P<0.001). However, there were no differences in the other neuropsychological tests. Daily dosing with a PDE5 inhibitor seems to improve cognitive function, depression and somatization, as well as erectile function, in patients with ED.
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18
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Ashina M, Hansen JM, Olesen J. Pearls and pitfalls in human pharmacological models of migraine: 30 years' experience. Cephalalgia 2013; 33:540-53. [DOI: 10.1177/0333102412475234] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In vitro studies have contributed to the characterization of receptors in cranial blood vessels and the identification of new possible anti-migraine agents. In vivo animal models enable the study of vascular responses, neurogenic inflammation, peptide release and genetic predisposition and thus have provided leads in the search for migraine mechanisms. All animal-based results must, however, be validated in human studies because so far no animal models can predict the efficacy of new therapies for migraine. Given the nature of migraine attacks, fully reversible and treatable, the headache- or migraine-provoking property of naturally occurring signaling molecules can be tested in a human model. If such an endogenous substance can provoke migraine in human patients, then it is likely, although not certain, that blocking its effect will be effective in the treatment of acute migraine attacks. To this end, a human in vivo model of experimental headache and migraine in humans has been developed. Human models of migraine offer unique possibilities to study mechanisms responsible for migraine and to explore the mechanisms of action of existing and future anti-migraine drugs. The human model has played an important role in translational migraine research leading to the identification of three new principally different targets in the treatment of acute migraine attacks and has been used to examine other endogenous signaling molecules as well as genetic susceptibility factors. New additions to the model, such as advanced neuroimaging, may lead to a better understanding of the complex events that constitute a migraine attack, and better and more targeted ways of intervention.
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Affiliation(s)
- Messoud Ashina
- Danish Headache Center and Department of Neurology, Glostrup Hospital, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Jakob Møller Hansen
- Danish Headache Center and Department of Neurology, Glostrup Hospital, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Jes Olesen
- Danish Headache Center and Department of Neurology, Glostrup Hospital, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
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19
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García-Osta A, Cuadrado-Tejedor M, García-Barroso C, Oyarzábal J, Franco R. Phosphodiesterases as therapeutic targets for Alzheimer's disease. ACS Chem Neurosci 2012; 3:832-44. [PMID: 23173065 DOI: 10.1021/cn3000907] [Citation(s) in RCA: 175] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Accepted: 10/01/2012] [Indexed: 01/10/2023] Open
Abstract
Alzheimer's disease (AD) is the most common form of dementia among the elderly. In AD patients, memory loss is accompanied by the formation of beta-amyloid plaques and the appearance of tau in a pathological form. Given the lack of effective treatments for AD, the development of new management strategies for these patients is critical. The continued failure to find effective therapies using molecules aimed at addressing the anti-beta amyloid pathology has led researchers to focus on other non-amyloid-based approaches to restore memory function. Promising non-amyloid related candidate targets include phosphosdiesterases (PDEs), and indeed, Rolipram, a specific PDE4 inhibitor, was the first compound found to effectively restore cognitive deficits in animal models of AD. More recently, PDE5 inhibitors have also been shown to effectively restore memory function. Accordingly, inhibitors of other members of the PDE family may also improve memory performance in AD and non-AD animal models. Hence, in this review, we will summarize the data supporting the use of PDE inhibitors as cognitive enhancers and we will discuss the possible mechanisms of action underlying these effects. We shall also adopt a medicinal chemistry perspective that leads us to propose the most promising PDE candidates on the basis of inhibitor selectivity, brain distribution, and mechanism of action.
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Affiliation(s)
- Ana García-Osta
- Molecular and Cell Neuropharmacology
Laboratory, Neurosciences Division, CIMA (Centro de investigación Médica Aplicada), Avda Pio
XII, Pamplona, Spain
| | - Mar Cuadrado-Tejedor
- Molecular and Cell Neuropharmacology
Laboratory, Neurosciences Division, CIMA (Centro de investigación Médica Aplicada), Avda Pio
XII, Pamplona, Spain
| | - Carolina García-Barroso
- Molecular and Cell Neuropharmacology
Laboratory, Neurosciences Division, CIMA (Centro de investigación Médica Aplicada), Avda Pio
XII, Pamplona, Spain
| | - Julen Oyarzábal
- Molecular and Cell Neuropharmacology
Laboratory, Neurosciences Division, CIMA (Centro de investigación Médica Aplicada), Avda Pio
XII, Pamplona, Spain
- Small
Molecule Discovery Platform, CIMA (Centro
de investigación Médica
Aplicada), Avda Pio XII, Pamplona, Spain
| | - Rafael Franco
- Molecular and Cell Neuropharmacology
Laboratory, Neurosciences Division, CIMA (Centro de investigación Médica Aplicada), Avda Pio
XII, Pamplona, Spain
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Affiliation(s)
- Andrew Charles
- David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.
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Reneerkens OA, Rutten K, Akkerman S, Blokland A, Shaffer CL, Menniti FS, Steinbusch HW, Prickaerts J. Phosphodiesterase type 5 (PDE5) inhibition improves object recognition memory: Indications for central and peripheral mechanisms. Neurobiol Learn Mem 2012; 97:370-9. [DOI: 10.1016/j.nlm.2012.02.008] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Revised: 02/16/2012] [Accepted: 02/27/2012] [Indexed: 01/10/2023]
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Kruuse C, Gupta S, Nilsson E, Kruse L, Edvinsson L. Differential vasoactive effects of sildenafil and tadalafil on cerebral arteries. Eur J Pharmacol 2012; 674:345-51. [DOI: 10.1016/j.ejphar.2011.10.037] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Revised: 10/14/2011] [Accepted: 10/30/2011] [Indexed: 11/27/2022]
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Kruuse C, Gupta S, Nilsson E, Kruse L, Edvinsson L. Differential vasoactive effects of sildenafil and tadalafil on cerebral arteries –relevant to migraine? BMC Pharmacol 2011. [PMCID: PMC3363237 DOI: 10.1186/1471-2210-11-s1-p42] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
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He Z, Cui L, Patterson TA, Paule MG. Defining the phosphodiesterase superfamily members in rat brain microvessels. ACS Chem Neurosci 2011; 2:600-7. [PMID: 22860158 DOI: 10.1021/cn2000487] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2011] [Accepted: 06/27/2011] [Indexed: 11/30/2022] Open
Abstract
Eleven phosphodiesterase (PDE) families are known, each having several different isoforms and splice variants. Recent evidence indicates that expression of individual PDE family members is tissue-specific. Little is known concerning detailed PDE component expression in brain microvessels where the blood-brain-barrier and the local cerebral blood flow are thought to be regulated by PDEs. The present study attempted to identify PDE family members that are expressed in brain microvessels. Adult male F344 rats were sacrificed and blocks of the cerebral cortex and infratentorial areas were dissected. Microvessels were isolated using a filtration method, and total RNA was extracted. RNA quality and quantity were determined using an Agilent bioanalyzer. The isolated cortical and infratentorial microvessel total RNA amounts were 2720 ± 750 ng (n = 2) and 250 ± 40 ng (n = 2), respectively. Microarrays with 22 000 transcripts demonstrated that there were 16 PDE transcripts in the PDE superfamily, exhibiting quantifiable density in the microvessels. An additional immunofluorescent study verified that PDE4D (cAMP-specific) and PDE5A (cGMP-specific) were colocalized with RECA-1 (an endothelial marker) in the cerebral cortex using both F344 rats and Sprague-Dawley rats (n = 3-6/strain). In addition, PDE4D and PDE5A were found to be colocalized with alpha-smooth muscle actin which delineates cerebral arteries and arterioles as well as pericytes. In conclusion, a filtration method followed by microarray analyses allows PDE components to be identified in brain microvessels, and confirmed that PDE4D and PDE5A are the primary forms expressed in rat brain microvessels.
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Affiliation(s)
- Zhen He
- Division of Neurotoxicology, National Center for Toxicological Research, Food and Drug Administration, Jefferson, Arkansas 72079, United States
| | - Li Cui
- Department of Neurology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, United States
| | - Tucker A. Patterson
- Division of Neurotoxicology, National Center for Toxicological Research, Food and Drug Administration, Jefferson, Arkansas 72079, United States
| | - Merle G. Paule
- Division of Neurotoxicology, National Center for Toxicological Research, Food and Drug Administration, Jefferson, Arkansas 72079, United States
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Pharmacological modulation of the bOLD response: A study of acetazolamide and glyceryl trinitrate in humans. J Magn Reson Imaging 2011; 34:921-7. [DOI: 10.1002/jmri.22659] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2010] [Accepted: 04/28/2011] [Indexed: 11/07/2022] Open
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Abstract
PURPOSE OF REVIEW The cranial blood vessel is considered an integral player in the pathophysiology of migraine, but its perceived role has been subject to much discussion and controversy over the years. We will discuss the evolution in our scientific understanding of cranial blood vessels (primarily arteries) in migraine. RECENT FINDINGS Recent developments have clarified the role of cranial blood vessels in the trigemino-vascular system and in cortical spreading depression. An underlying theme is the intimate relation between vascular activity and neural function, and we will emphasize the various roles of the blood vessel that go beyond delivering blood. We conclude that migraine cannot be understood, either from a research or clinical point of view, without an understanding of the vascular derangements that accompany it. SUMMARY Migraine is accompanied by significant derangements in vascular function that may represent important targets for investigation and treatment.
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Affiliation(s)
- K C Brennan
- Department of Neurology, David Geffen School of Medicine at UCLA, California, USA.
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