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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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2
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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: 0] [Impact Index Per Article: 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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3
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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.
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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,
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Carr JM, Ainslie PN, MacLeod DB, Tremblay JC, Nowak-Flück D, Howe CA, Stembridge M, Patrician A, Coombs GB, Stacey BS, Bailey DM, Green DJ, Hoiland RL. Cerebral O 2 and CO 2 transport in isovolumic haemodilution: Compensation of cerebral delivery of O 2 and maintenance of cerebrovascular reactivity to CO 2. J Cereb Blood Flow Metab 2023; 43:99-114. [PMID: 36131560 PMCID: PMC9875354 DOI: 10.1177/0271678x221119442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
This study investigated the influence of acute reductions in arterial O2 content (CaO2) via isovolumic haemodilution on global cerebral blood flow (gCBF) and cerebrovascular CO2 reactivity (CVR) in 11 healthy males (age; 28 ± 7 years: body mass index; 23 ± 2 kg/m2). Radial artery and internal jugular vein catheters provided measurement of blood pressure and gases, quantification of cerebral metabolism, cerebral CO2 washout, and trans-cerebral nitrite exchange (ozone based chemiluminescence). Prior to and following haemodilution, the partial pressure of arterial CO2 (PaCO2) was elevated with dynamic end-tidal forcing while gCBF was measured with duplex ultrasound. CVR was determined as the slope of the gCBF response and PaCO2. Replacement of ∼20% of blood volume with an equal volume of 5% human serum albumin (Alburex® 5%) reduced haemoglobin (13.8 ± 0.8 vs. 11.3 ± 0.6 g/dL; P < 0.001) and CaO2 (18.9 ± 1.0 vs 15.0 ± 0.8 mL/dL P < 0.001), elevated gCBF (+18 ± 11%; P = 0.002), preserved cerebral oxygen delivery (P = 0.49), and elevated CO2 washout (+11%; P = 0.01). The net cerebral uptake of nitrite (11.6 ± 14.0 nmol/min; P = 0.027) at baseline was abolished following haemodilution (-3.6 ± 17.9 nmol/min; P = 0.54), perhaps underpinning the conservation of CVR (61.7 ± 19.0 vs. 69.0 ± 19.2 mL/min/mmHg; P = 0.23). These findings demonstrate that the cerebrovascular responses to acute anaemia in healthy humans are sufficient to support the maintenance of CVR.
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Affiliation(s)
- Jay Mjr Carr
- Centre for Heart, Lung and Vascular Health, University of British Columbia - Okanagan Campus, School of Health and Exercise Sciences, Kelowna, B.C., Canada, V1V 1V7
| | - Philip N Ainslie
- Centre for Heart, Lung and Vascular Health, University of British Columbia - Okanagan Campus, School of Health and Exercise Sciences, Kelowna, B.C., Canada, V1V 1V7
| | - David B MacLeod
- Human Pharmacology & Physiology Lab, Department of Anesthesiology, Duke University Medical Center, Durham, NC, USA
| | - Joshua C Tremblay
- Centre for Heart, Lung and Vascular Health, University of British Columbia - Okanagan Campus, School of Health and Exercise Sciences, Kelowna, B.C., Canada, V1V 1V7
| | - Daniela Nowak-Flück
- Centre for Heart, Lung and Vascular Health, University of British Columbia - Okanagan Campus, School of Health and Exercise Sciences, Kelowna, B.C., Canada, V1V 1V7
| | - Connor A Howe
- Centre for Heart, Lung and Vascular Health, University of British Columbia - Okanagan Campus, School of Health and Exercise Sciences, Kelowna, B.C., Canada, V1V 1V7
| | - Mike Stembridge
- Cardiff School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, UK
| | - Alexander Patrician
- Centre for Heart, Lung and Vascular Health, University of British Columbia - Okanagan Campus, School of Health and Exercise Sciences, Kelowna, B.C., Canada, V1V 1V7
| | - Geoff B Coombs
- Centre for Heart, Lung and Vascular Health, University of British Columbia - Okanagan Campus, School of Health and Exercise Sciences, Kelowna, B.C., Canada, V1V 1V7.,School of Kinesiology, Faculty of Health Sciences, University of Western Ontario, London, Ontario, Canada
| | - Benjamin S Stacey
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, UK
| | - Damian M Bailey
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, UK
| | - Daniel J Green
- School of Human Sciences (Exercise and Sport Sciences), The University of Western Australia, Nedlands, Western Australia
| | - Ryan L Hoiland
- Centre for Heart, Lung and Vascular Health, University of British Columbia - Okanagan Campus, School of Health and Exercise Sciences, Kelowna, B.C., Canada, V1V 1V7.,Department of Anesthesiology, Pharmacology and Therapeutics, Faculty of Medicine, Vancouver General Hospital, University of British Columbia, Vancouver, BC, Canada.,Department of Cellular and Physiological Sciences, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada.,International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada
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5
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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: 16] [Impact Index Per Article: 8.0] [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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6
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Claassen JAHR, Thijssen DHJ, Panerai RB, Faraci FM. Regulation of cerebral blood flow in humans: physiology and clinical implications of autoregulation. Physiol Rev 2021; 101:1487-1559. [PMID: 33769101 PMCID: PMC8576366 DOI: 10.1152/physrev.00022.2020] [Citation(s) in RCA: 275] [Impact Index Per Article: 91.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Brain function critically depends on a close matching between metabolic demands, appropriate delivery of oxygen and nutrients, and removal of cellular waste. This matching requires continuous regulation of cerebral blood flow (CBF), which can be categorized into four broad topics: 1) autoregulation, which describes the response of the cerebrovasculature to changes in perfusion pressure; 2) vascular reactivity to vasoactive stimuli [including carbon dioxide (CO2)]; 3) neurovascular coupling (NVC), i.e., the CBF response to local changes in neural activity (often standardized cognitive stimuli in humans); and 4) endothelium-dependent responses. This review focuses primarily on autoregulation and its clinical implications. To place autoregulation in a more precise context, and to better understand integrated approaches in the cerebral circulation, we also briefly address reactivity to CO2 and NVC. In addition to our focus on effects of perfusion pressure (or blood pressure), we describe the impact of select stimuli on regulation of CBF (i.e., arterial blood gases, cerebral metabolism, neural mechanisms, and specific vascular cells), the interrelationships between these stimuli, and implications for regulation of CBF at the level of large arteries and the microcirculation. We review clinical implications of autoregulation in aging, hypertension, stroke, mild cognitive impairment, anesthesia, and dementias. Finally, we discuss autoregulation in the context of common daily physiological challenges, including changes in posture (e.g., orthostatic hypotension, syncope) and physical activity.
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Affiliation(s)
- Jurgen A H R Claassen
- Department of Geriatrics, Radboud University Medical Center, Donders Institute for Brain, Cognition, and Behaviour, Nijmegen, The Netherlands
| | - Dick H J Thijssen
- Department of Physiology, Radboud Institute for Health Sciences, Nijmegen, The Netherlands
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Ronney B Panerai
- Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
- >National Institute for Health Research Leicester Biomedical Research Centre, University of Leicester, Leicester, United Kingdom
| | - Frank M Faraci
- Departments of Internal Medicine, Neuroscience, and Pharmacology, Carver College of Medicine, University of Iowa, Iowa City, Iowa
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Williams JS, Dunford EC, Cheng JL, Moncion K, Valentino SE, Droog CA, Cherubini JM, King TJ, Noguchi KS, Wiley E, Turner JR, Tang A, Al-Khazraji BK, MacDonald MJ. The impact of the 24-h movement spectrum on vascular remodeling in older men and women: a review. Am J Physiol Heart Circ Physiol 2021; 320:H1136-H1155. [PMID: 33449851 DOI: 10.1152/ajpheart.00754.2020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Aging is associated with increased risk of cardiovascular and cerebrovascular events, which are preceded by early, negative remodeling of the vasculature. Low physical activity is a well-established risk factor associated with the incidence and development of disease. However, recent physical activity literature indicates the importance of considering the 24-h movement spectrum. Therefore, the purpose of this review was to examine the impact of the 24-h movement spectrum, specifically physical activity (aerobic and resistance training), sedentary behavior, and sleep, on cardiovascular and cerebrovascular outcomes in older adults, with a focus on recent evidence (<10 yr) and sex-based considerations. The review identifies that both aerobic training and being physically active (compared with sedentary) are associated with improvements in endothelial function, arterial stiffness, and cerebrovascular function. Additionally, there is evidence of sex-based differences in endothelial function: a blunted improvement in aerobic training in postmenopausal women compared with men. While minimal research has been conducted in older adults, resistance training does not appear to influence arterial stiffness. Poor sleep quantity or quality are associated with both impaired endothelial function and increased arterial stiffness. Finally, the review highlights mechanistic pathways involved in the regulation of vascular and cerebrovascular function, specifically the balance between pro- and antiatherogenic factors, which mediate the relationship between the 24-h movement spectrum and vascular outcomes. Finally, this review proposes future research directions: examining the role of duration and intensity of training, combining aerobic and resistance training, and exploration of sex-based differences in cardiovascular and cerebrovascular outcomes.
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Affiliation(s)
- Jennifer S Williams
- Vascular Dynamics Lab, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - Emily C Dunford
- Vascular Dynamics Lab, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - Jem L Cheng
- Vascular Dynamics Lab, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - Kevin Moncion
- MacStroke Canada, School of Rehabilitation Sciences, McMaster University, Hamilton, Ontario, Canada
| | - Sydney E Valentino
- Vascular Dynamics Lab, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - Connor A Droog
- Vascular Dynamics Lab, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - Joshua M Cherubini
- Vascular Dynamics Lab, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - Trevor J King
- Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - Kenneth S Noguchi
- MacStroke Canada, School of Rehabilitation Sciences, McMaster University, Hamilton, Ontario, Canada
| | - Elise Wiley
- MacStroke Canada, School of Rehabilitation Sciences, McMaster University, Hamilton, Ontario, Canada
| | - Joshua R Turner
- Vascular Dynamics Lab, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - Ada Tang
- MacStroke Canada, School of Rehabilitation Sciences, McMaster University, Hamilton, Ontario, Canada
| | | | - Maureen J MacDonald
- Vascular Dynamics Lab, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
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8
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He Y, Gu M, Zhang H, Deng J, Wu X, Guo Y. Effect of insomnia after acute ischemic stroke on cerebrovascular reactivity: a prospective clinical study in China. Sleep Med 2019; 63:82-87. [DOI: 10.1016/j.sleep.2019.07.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Revised: 06/28/2019] [Accepted: 07/04/2019] [Indexed: 11/16/2022]
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9
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Hoiland RL, Fisher JA, Ainslie PN. Regulation of the Cerebral Circulation by Arterial Carbon Dioxide. Compr Physiol 2019; 9:1101-1154. [DOI: 10.1002/cphy.c180021] [Citation(s) in RCA: 101] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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10
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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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