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Srichawla BS. Future of neurocritical care: Integrating neurophysics, multimodal monitoring, and machine learning. World J Crit Care Med 2024; 13:91397. [PMID: 38855276 PMCID: PMC11155497 DOI: 10.5492/wjccm.v13.i2.91397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 01/27/2024] [Accepted: 03/06/2024] [Indexed: 06/03/2024] Open
Abstract
Multimodal monitoring (MMM) in the intensive care unit (ICU) has become increasingly sophisticated with the integration of neurophysical principles. However, the challenge remains to select and interpret the most appropriate combination of neuromonitoring modalities to optimize patient outcomes. This manuscript reviewed current neuromonitoring tools, focusing on intracranial pressure, cerebral electrical activity, metabolism, and invasive and noninvasive autoregulation monitoring. In addition, the integration of advanced machine learning and data science tools within the ICU were discussed. Invasive monitoring includes analysis of intracranial pressure waveforms, jugular venous oximetry, monitoring of brain tissue oxygenation, thermal diffusion flowmetry, electrocorticography, depth electroencephalography, and cerebral microdialysis. Noninvasive measures include transcranial Doppler, tympanic membrane displacement, near-infrared spectroscopy, optic nerve sheath diameter, positron emission tomography, and systemic hemodynamic monitoring including heart rate variability analysis. The neurophysical basis and clinical relevance of each method within the ICU setting were examined. Machine learning algorithms have shown promise by helping to analyze and interpret data in real time from continuous MMM tools, helping clinicians make more accurate and timely decisions. These algorithms can integrate diverse data streams to generate predictive models for patient outcomes and optimize treatment strategies. MMM, grounded in neurophysics, offers a more nuanced understanding of cerebral physiology and disease in the ICU. Although each modality has its strengths and limitations, its integrated use, especially in combination with machine learning algorithms, can offer invaluable information for individualized patient care.
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Affiliation(s)
- Bahadar S Srichawla
- Department of Neurology, University of Massachusetts Chan Medical School, Worcester, MA 01655, United States
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Rajan RK, Kumar RP, Ramanathan M. Piceatannol improved cerebral blood flow and attenuated JNK3 and mitochondrial apoptotic pathway in a global ischemic model to produce neuroprotection. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2024; 397:479-496. [PMID: 37470802 DOI: 10.1007/s00210-023-02616-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Accepted: 07/07/2023] [Indexed: 07/21/2023]
Abstract
Cerebral ischemia is one of the leading causes of death and disability worldwide. The only FDA-approved treatment is recanalization with systemic tissue plasminogen activators like alteplase, although reperfusion caused by recanalization can result in neuroinflammation, which can cause brain cell apoptosis. Therefore, after an ischemic/reperfusion injury, interventions are needed to minimize the neuroinflammatory cascade. In the present study, piceatannol (PCT) was studied for its neuroprotective efficacy in a rat model of global ischemic injury by attenuating c-Jun N-terminal kinase 3 (JNK3) downstream signaling. PCT is a resveratrol analog and a polyphenolic stilbenoid naturally occurring in passion fruit and grapes. The neuroprotective efficacy of PCT (1, 5, 10 mg/kg) in ischemic conditions was assessed through pre- and post-treatment. Cerebral blood flow (CBF) and tests for functional recovery were assessed. Protein and gene expression were done for JNK3 and other inflammatory markers. A docking study was performed to identify the amino acid interaction. The results showed that PCT improved motor and memory function as measured by a functional recovery test believed to be due to an increase in cerebral blood flow. Also, the caspase signaling which promotes apoptosis was found to be down-regulated; however, nitric oxide synthase expression was up-regulated, which could explain the enhanced cerebral blood flow (CBF). According to our findings, PCT impeded c-Jun N-terminal kinase 3 (JNK3) signaling by suppressing phosphorylation and disrupting the mitochondrial apoptotic pathway, which resulted in the neuroprotective effect. Molecular docking analysis was performed to investigate the atomic-level interaction of JNK3 and PCT, which reveals that Met149, Leu206, and Lys93 amino acid residues are critical for the interaction of PCT and JNK3. According to our current research, JNK3 downstream signaling and the mitochondrial apoptosis pathway are both inhibited by PCT, which results in neuroprotection under conditions of global brain ischemia. Piceatannol attenuated JNK3 phosphorylation during the ischemic condition and prevented neuronal apoptosis.
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Affiliation(s)
- Ravi Kumar Rajan
- Department of Pharmacology, PSG College of Pharmacy, Coimbatore, 641004, Tamilnadu, India.
- Department of Pharmacology, Girijananda Chowdhury Institute of Pharmaceutical Science, Girijananda Chowdhury University, Dekargaon, Tezpur, 784501, Assam, India.
| | - Ram Pravin Kumar
- Department of Pharmacology, PSG College of Pharmacy, Coimbatore, 641004, Tamilnadu, India
| | - M Ramanathan
- Department of Pharmacology, PSG College of Pharmacy, Coimbatore, 641004, Tamilnadu, India
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Corrêa DI, de-Lima-Oliveira M, Nogueira RC, Carvalho-Pinto RM, Bor-Seng-Shu E, Panerai RB, Carvalho CRF, Salinet AS. Integrative assessment of cerebral blood regulation in COPD patients. Respir Physiol Neurobiol 2024; 319:104166. [PMID: 37758031 DOI: 10.1016/j.resp.2023.104166] [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] [Received: 05/18/2023] [Revised: 09/16/2023] [Accepted: 09/23/2023] [Indexed: 10/03/2023]
Abstract
Cerebrovascular responses were compared between COPD and non-COPD participants. The association between COPD severity and cognitive function was also investigated. Cerebral blood velocity in the middle cerebral artery, blood pressure, and end-tidal CO2 were recorded at rest, followed by a brain activation paradigm, and an inhaled gas mixture (5% CO2) to assess cerebral autoregulation (CA), neurovascular coupling (NVC) and cerebrovascular reactivity to carbon dioxide (CVRCO2), respectively. Pulmonary function, blood gas analysis (COPD) and cognitive function (MoCA test) were also performed. No difference in baseline (systemic and cerebral parameters) and CA was found between 20 severe COPD and 21 non-COPD. Reduced NVC and CVRCO2 test were found in the COPD group. Lower pulmonary function was positively correlated with CA, NVC and CVRCO2 in COPD patients. Cognitive impairment (MoCA<26) was associated with lower NVC responses (COPD and non-COPD) and lower pulmonary function (COPD). Both mechanisms, CVRCO2 and NVC, were lower in COPD patients. Moreover, disease severity and cognitive impaired were associated with worse cerebrovascular regulation.
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Affiliation(s)
- Daniel I Corrêa
- Neurology Department, School of Medicine, Hospital das Clinicas, University of São Paulo, São Paulo, Brazil
| | - Marcelo de-Lima-Oliveira
- Neurology Department, School of Medicine, Hospital das Clinicas, University of São Paulo, São Paulo, Brazil
| | - Ricardo C Nogueira
- Neurology Department, School of Medicine, Hospital das Clinicas, University of São Paulo, São Paulo, Brazil
| | - Regina M Carvalho-Pinto
- Pulmonary Division, Heart Institute (InCor), Hospital das Clínicas, School of Medicine, University of São Paulo, São Paulo, Brazil
| | - Edson Bor-Seng-Shu
- Neurology Department, School of Medicine, Hospital das Clinicas, University of São Paulo, São Paulo, Brazil
| | - Ronney B Panerai
- Department of Cardiovascular Sciences, University of Leicester and NIHR Biomedical Research Centre, Leicester, UK
| | - Celso R F Carvalho
- Department of Physical Therapy, School of Medicine, University of São Paulo, Brazil
| | - Angela Sm Salinet
- Neurology Department, School of Medicine, Hospital das Clinicas, University of São Paulo, São Paulo, Brazil.
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Wang Y, Payne SJ. Static autoregulation in humans. J Cereb Blood Flow Metab 2023:271678X231210430. [PMID: 37933742 DOI: 10.1177/0271678x231210430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2023]
Abstract
The process by which cerebral blood flow (CBF) remains approximately constant in response to short-term variations in arterial blood pressure (ABP) is known as cerebral autoregulation. This classic view, that it remains constant over a wide range of ABP, has however been challenged by a growing number of studies. To provide an updated understanding of the static cerebral pressure-flow relationship and to characterise the autoregulation curve more rigorously, we conducted a comprehensive literature research. Results were based on 143 studies in healthy individuals aged 18 to 65 years. The mean sensitivities of CBF to changes in ABP were found to be 1.47 ± 0.71%/% for decreased ABP and 0.37 ± 0.38%/% for increased ABP. The significant difference in CBF directional sensitivity suggests that cerebral autoregulation appears to be more effective in buffering increases in ABP than decreases in ABP. Regression analysis of absolute CBF and ABP identified an autoregulatory plateau of approximately 20 mmHg (ABP between 80 and 100 mmHg), which is much smaller than the widely accepted classical view. Age and sex were found to have no effect on autoregulation strength. This data-driven approach provides a quantitative method of analysing static autoregulation that can be easily updated as more experimental data become available.
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Affiliation(s)
- Yufan Wang
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, UK
| | - Stephen J Payne
- Institute of Applied Mechanics, National Taiwan University, Taipei
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Pobbati H, Ghosh SK, Gautam D. Clinical Utility of Arterial Spin Labeling Magnetic Resonance Imaging in the Evaluation of the Brain. J Med Phys 2023; 48:378-383. [PMID: 38223788 PMCID: PMC10783186 DOI: 10.4103/jmp.jmp_64_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 07/19/2023] [Accepted: 10/04/2023] [Indexed: 01/16/2024] Open
Abstract
Introduction Cerebral blood flow (CBF) is essential for studying the brain in both normal and diseased states. Arterial spin labeling (ASL) is a functional magnetic resonance imaging (MRI) technique that uses arterial water as an endogenous tracer to measure CBF, thus does not require an injection of exogenous tracers and is noninvasive and can therefore be used to track changes in CBF. Materials and Methods This prospective, observational and descriptive study was done at the department of imaging, Maxcure Hospital, Hyderabad, for the duration of 18 months. All studies were performed on a 1.5T Philips Prodiva CX using a phased array coil. Results A prospective observational and descriptive study was done among 100 patients to study the clinical utility of ASL. Out of 100 patients, 20 (20%) patients showed normal MRI findings. Rest 80 (80%) patients had abnormal MRI findings. Conclusion ASL provides additional and complementary information to that available from structural MRI in all categories of abnormalities.
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Affiliation(s)
| | - Sumit Kumar Ghosh
- Department of Radio-Diagnosis, KIMS Hospital, Hyderabad, Telangana, India
| | - Deeksha Gautam
- Department of Radio-Diagnosis, KIMS Hospital, Hyderabad, Telangana, India
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Owens TS, Marley CJ, Calverley TA, Stacey BS, Fall L, Tsukamoto H, Iannetelli A, Filipponi T, Davies B, Jones GL, Hirtz C, Lehmann S, Tuaillon E, Marchi N, Bailey DM. Lower systemic nitric oxide bioactivity, cerebral hypoperfusion and accelerated cognitive decline in formerly concussed retired rugby union players. Exp Physiol 2023; 108:1029-1046. [PMID: 37423736 PMCID: PMC10988504 DOI: 10.1113/ep091195] [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] [Received: 02/27/2023] [Accepted: 06/12/2023] [Indexed: 07/11/2023]
Abstract
NEW FINDINGS What is the central question of this study? What are the molecular, cerebrovascular and cognitive biomarkers of retired rugby union players with concussion history? What is the main finding and its importance? Retired rugby players compared with matched controls exhibited lower systemic nitric oxide bioavailability accompanied by lower middle cerebral artery velocity and mild cognitive impairment. Retired rugby players are more susceptible to accelerated cognitive decline. ABSTRACT Following retirement from sport, the chronic consequences of prior-recurrent contact are evident and retired rugby union players may be especially prone to accelerated cognitive decline. The present study sought to integrate molecular, cerebrovascular and cognitive biomarkers in retired rugby players with concussion history. Twenty retired rugby players aged 64 ± 5 years with three (interquartile range (IQR), 3) concussions incurred over 22 (IQR, 6) years were compared to 21 sex-, age-, cardiorespiratory fitness- and education-matched controls with no prior concussion history. Concussion symptoms and severity were assessed using the Sport Concussion Assessment Tool. Plasma/serum nitric oxide (NO) metabolites (reductive ozone-based chemiluminescence), neuron specific enolase, glial fibrillary acidic protein and neurofilament light-chain (ELISA and single molecule array) were assessed. Middle cerebral artery blood velocity (MCAv, doppler ultrasound) and reactivity to hyper/hypocapnia (CVR CO 2 hyper ${\mathrm{CVR}}_{{\mathrm{CO}}_{\mathrm{2}}{\mathrm{hyper}}}$ /CVR CO 2 hypo ${\mathrm{CVR}}_{{\mathrm{CO}}_{\mathrm{2}}{\mathrm{hypo}}}$ ) were assessed. Cognition was determined using the Grooved Pegboard Test and Montreal Cognitive Assessment. Players exhibited persistent neurological symptoms of concussion (U = 109(41) , P = 0.007), with increased severity compared to controls (U = 77(41) , P < 0.001). Lower total NO bioactivity (U = 135(41) , P = 0.049) and lower basal MCAv were apparent in players (F2,39 = 9.344, P = 0.004). This was accompanied by mild cognitive impairment (P = 0.020, 95% CI, -3.95 to -0.34), including impaired fine-motor coordination (U = 141(41) , P = 0.021). Retired rugby union players with history of multiple concussions may be characterised by impaired molecular, cerebral haemodynamic and cognitive function compared to non-concussed, non-contact controls.
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Affiliation(s)
- Thomas S. Owens
- Neurovascular Research Laboratory, Faculty of Life Sciences and EducationUniversity of South WalesUK
| | - Christopher J. Marley
- Neurovascular Research Laboratory, Faculty of Life Sciences and EducationUniversity of South WalesUK
| | - Thomas A. Calverley
- Neurovascular Research Laboratory, Faculty of Life Sciences and EducationUniversity of South WalesUK
| | - Benjamin S. Stacey
- Neurovascular Research Laboratory, Faculty of Life Sciences and EducationUniversity of South WalesUK
| | - Lewis Fall
- Faculty of Computing, Engineering and ScienceUniversity of South WalesUK
| | | | - Angelo Iannetelli
- Neurovascular Research Laboratory, Faculty of Life Sciences and EducationUniversity of South WalesUK
| | - Teresa Filipponi
- Neurovascular Research Laboratory, Faculty of Life Sciences and EducationUniversity of South WalesUK
| | - Bruce Davies
- Neurovascular Research Laboratory, Faculty of Life Sciences and EducationUniversity of South WalesUK
| | - Gareth L. Jones
- Neurovascular Research Laboratory, Faculty of Life Sciences and EducationUniversity of South WalesUK
| | - Christophe Hirtz
- LBPC‐PPCUniversity of Montpellier, Institute of Regenerative Medicine‐Biotherapy IRMB, Centre Hospitalier Universitaire de Montpellier, INSERMMontpellierFrance
| | - Sylvain Lehmann
- LBPC‐PPCUniversity of Montpellier, Institute of Regenerative Medicine‐Biotherapy IRMB, Centre Hospitalier Universitaire de Montpellier, INSERMMontpellierFrance
| | - Edouard Tuaillon
- CHU Montpellier, Department of Bacteriology‐VirologyCentre University ofMontpellierFrance
| | - Nicola Marchi
- Cerebrovascular and Glia Research, Department of NeuroscienceInstitute of Functional Genomics (University of Montpellier, CNRS, INSERM)MontpellierFrance
| | - Damian M. Bailey
- Neurovascular Research Laboratory, Faculty of Life Sciences and EducationUniversity of South WalesUK
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Corkery AT, Miller KB, Loeper CA, Tetri LH, Pearson AG, Loggie NA, Howery AJ, Eldridge MW, Barnes JN. Association between serum prostacyclin and cerebrovascular reactivity in healthy young and older adults. Exp Physiol 2023; 108:1047-1056. [PMID: 37170828 PMCID: PMC10524213 DOI: 10.1113/ep090903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 04/17/2023] [Indexed: 05/13/2023]
Abstract
NEW FINDINGS What is the central question of this study? What is the relationship between prostacyclin and cerebrovascular reactivity to hypercapnia before and after administration of a cyclooxygenase inhibitor, indomethacin, in healthy young and older adults? What is the main finding and importance? Serum prostacyclin was not related to cerebrovascular reactivity to hypercapnia before or after administration of indomethacin. However, in older adults, serum prostacyclin was related to the magnitude of change in cerebrovascular reactivity from before to after indomethacin administration. This suggests that older adults with higher serum prostacyclin may rely more on cyclooxygenase products to mediate cerebrovascular reactivity. ABSTRACT Platelet activation may contribute to age-related cerebrovascular dysfunction by interacting with the endothelial cells that regulate the response to vasodilatory stimuli. This study evaluated the relationship between a platelet inhibitor, prostacyclin, and cerebrovascular reactivity (CVR) in healthy young (n = 35; 25 ± 4 years; 17 women, 18 men) and older (n = 12; 62 ± 2 years; 8 women, 4 men) adults, who were not daily aspirin users, before and after cyclooxygenase inhibition. Prostacyclin was determined by levels of 6-keto-prostaglandin F1α (6-keto PGF1α) in the blood. CVR was assessed by measuring the middle cerebral artery blood velocity response to hypercapnia using transcranial Doppler ultrasound before (CON) and 90 min after cyclooxygenase inhibition with indomethacin (INDO). In young adults, there were no associations between prostacyclin and middle cerebral artery CVR during CON (r = -0.14, P = 0.415) or INDO (r = 0.27, P = 0.118). In older adults, associations between prostacyclin and middle cerebral artery CVR during CON (r = 0.53, P = 0.075) or INDO (r = -0.45, P = 0.136) did not reach the threshold for significance. We also evaluated the relationship between prostacyclin and the change in CVR between conditions (ΔCVR). We found no association between ΔCVR and prostacyclin in young adults (r = 0.27, P = 0.110); however, in older adults, those with higher baseline prostacyclin levels demonstrated significantly greater ΔCVR (r = -0.74, P = 0.005). In conclusion, older adults with higher serum prostacyclin, a platelet inhibitor, may rely more on cyclooxygenase products for cerebrovascular reactivity to hypercapnia.
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Affiliation(s)
- Adam T Corkery
- Bruno Balke Biodynamics Laboratory, Department of Kinesiology, University of Wisconsin Madison, Madison, WI, USA
| | - Kathleen B Miller
- Bruno Balke Biodynamics Laboratory, Department of Kinesiology, University of Wisconsin Madison, Madison, WI, USA
| | - Carissa A Loeper
- Bruno Balke Biodynamics Laboratory, Department of Kinesiology, University of Wisconsin Madison, Madison, WI, USA
| | - Laura H Tetri
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Andrew G Pearson
- Bruno Balke Biodynamics Laboratory, Department of Kinesiology, University of Wisconsin Madison, Madison, WI, USA
| | - Nicole A Loggie
- Bruno Balke Biodynamics Laboratory, Department of Kinesiology, University of Wisconsin Madison, Madison, WI, USA
| | - Anna J Howery
- Bruno Balke Biodynamics Laboratory, Department of Kinesiology, University of Wisconsin Madison, Madison, WI, USA
| | - Marlowe W Eldridge
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Jill N Barnes
- Bruno Balke Biodynamics Laboratory, Department of Kinesiology, University of Wisconsin Madison, Madison, WI, USA
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Schmithorst VJ, Adams PS, Badaly D, Lee VK, Wallace J, Beluk N, Votava-Smith JK, Weinberg JG, Beers SR, Detterich J, Wood JC, Lo CW, Panigrahy A. Impaired Neurovascular Function Underlies Poor Neurocognitive Outcomes and Is Associated with Nitric Oxide Bioavailability in Congenital Heart Disease. Metabolites 2022; 12:metabo12090882. [PMID: 36144286 PMCID: PMC9504090 DOI: 10.3390/metabo12090882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Revised: 09/14/2022] [Accepted: 09/15/2022] [Indexed: 12/03/2022] Open
Abstract
We use a non-invasive MRI proxy of neurovascular function (pnvf) to assess the ability of the vasculature to supply baseline metabolic demand, to compare pediatric and young adult congenital heart disease (CHD) patients to normal referents and relate the proxy to neurocognitive outcomes and nitric oxide bioavailability. In a prospective single-center study, resting-state blood-oxygen-level-dependent (BOLD) and arterial spin labeling (ASL) MRI scans were successfully obtained from 24 CHD patients (age = 15.4 ± 4.06 years) and 63 normal referents (age = 14.1 ± 3.49) years. Pnvf was computed on a voxelwise basis as the negative of the ratio of functional connectivity strength (FCS) estimated from the resting-state BOLD acquisition to regional cerebral blood flow (rCBF) as estimated from the ASL acquisition. Pnvf was used to predict end-tidal CO2 (PETCO2) levels and compared to those estimated from the BOLD data. Nitric oxide availability was obtained via nasal measurements (nNO). Pnvf was compared on a voxelwise basis between CHD patients and normal referents and correlated with nitric oxide availability and neurocognitive outcomes as assessed via the NIH Toolbox. Pnvf was shown as highly predictive of PETCO2 using theoretical modeling. Pnvf was found to be significantly reduced in CHD patients in default mode network (DMN, comprising the ventromedial prefrontal cortex and posterior cingulate/precuneus), salience network (SN, comprising the insula and dorsal anterior cingulate), and central executive network (CEN, comprising posterior parietal and dorsolateral prefrontal cortex) regions with similar findings noted in single cardiac ventricle patients. Positive correlations of Pnvf in these brain regions, as well as the hippocampus, were found with neurocognitive outcomes. Similarly, positive correlations between Pnvf and nitric oxide availability were found in frontal DMN and CEN regions, with particularly strong correlations in subcortical regions (putamen). Reduced Pnvf in CHD patients was found to be mediated by nNO. Mediation analyses further supported that reduced Pnvf in these regions underlies worse neurocognitive outcome in CHD patients and is associated with nitric oxide bioavailability. Impaired neuro-vascular function, which may be non-invasively estimated via combined arterial-spin label and BOLD MR imaging, is a nitric oxide bioavailability dependent factor implicated in adverse neurocognitive outcomes in pediatric and young adult CHD.
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Affiliation(s)
| | - Phillip S. Adams
- Department of Pediatric Anesthesiology, UPMC Children’s Hospital, Pittsburgh, PA 15224, USA
| | - Daryaneh Badaly
- Learning and Development Center, Child Mind Institute, New York, NY 10022, USA
| | - Vincent K. Lee
- Department of Pediatric Radiology, UPMC Children’s Hospital, Pittsburgh, PA 15224, USA
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Julia Wallace
- Department of Pediatric Radiology, UPMC Children’s Hospital, Pittsburgh, PA 15224, USA
| | - Nancy Beluk
- Department of Pediatric Radiology, UPMC Children’s Hospital, Pittsburgh, PA 15224, USA
| | | | | | - Sue R. Beers
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Jon Detterich
- Heart Institute, Children’s Hospital Los Angeles, Los Angeles, CA 90027, USA
| | - John C. Wood
- Heart Institute, Children’s Hospital Los Angeles, Los Angeles, CA 90027, USA
| | - Cecilia W. Lo
- Department of Developmental Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Ashok Panigrahy
- Department of Pediatric Radiology, UPMC Children’s Hospital, Pittsburgh, PA 15224, USA
- Department of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
- Correspondence: ; Tel.: +1-412-692-5510; Fax: +1-412-692-6929
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Watanabe H, Saito S, Washio T, Bailey DM, Ogoh S. Acute Gravitational Stress Selectively Impairs Dynamic Cerebrovascular Reactivity in the Anterior Circulation Independent of Changes to the Central Respiratory Chemoreflex. Front Physiol 2022; 12:749255. [PMID: 35069233 PMCID: PMC8770752 DOI: 10.3389/fphys.2021.749255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 12/03/2021] [Indexed: 11/13/2022] Open
Abstract
Cerebrovascular reactivity (CVR) to changes in the partial pressure of arterial carbon dioxide (PaCO2) is an important mechanism that maintains CO2 or pH homeostasis in the brain. To what extent this is influenced by gravitational stress and corresponding implications for the regulation of cerebral blood flow (CBF) remain unclear. The present study examined the onset responses of pulmonary ventilation (V̇E) and anterior middle (MCA) and posterior (PCA) cerebral artery mean blood velocity (Vmean) responses to acute hypercapnia (5% CO2) to infer dynamic changes in the central respiratory chemoreflex and cerebrovascular reactivity (CVR), in supine and 50° head-up tilt (HUT) positions. Each onset response was evaluated using a single-exponential regression model consisting of the response time latency [CO2-response delay (t0)] and time constant (τ). Onset response of V̇E and PCA Vmean to changes in CO2 was unchanged during 50° HUT compared with supine (τ: V̇E, p = 0.707; PCA Vmean, p = 0.071 vs. supine) but the MCA Vmean onset response was faster during supine than during 50° HUT (τ: p = 0.003 vs. supine). These data indicate that gravitational stress selectively impaired dynamic CVR in the anterior cerebral circulation, whereas the posterior circulation was preserved, independent of any changes to the central respiratory chemoreflex. Collectively, our findings highlight the regional heterogeneity underlying CBF regulation that may have translational implications for the microgravity (and hypercapnia) associated with deep-space flight notwithstanding terrestrial orthostatic diseases that have been linked to accelerated cognitive decline and neurodegeneration.
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Affiliation(s)
- Hironori Watanabe
- Department of Biomedical Engineering, Toyo University, Kawagoe, Japan
| | - Shotaro Saito
- Department of Biomedical Engineering, Toyo University, Kawagoe, Japan
| | - Takuro Washio
- Department of Biomedical Engineering, Toyo University, Kawagoe, Japan.,Research Fellow of Japan Society for the Promotion of Science, Tokyo, Japan
| | - Damian Miles Bailey
- Research Fellow of Japan Society for the Promotion of Science, Tokyo, Japan.,Neurovascular Research Laboratory, University of South Wales, Pontypridd, United Kingdom
| | - Shigehiko Ogoh
- Department of Biomedical Engineering, Toyo University, Kawagoe, Japan.,Neurovascular Research Laboratory, University of South Wales, Pontypridd, United Kingdom
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Owens TS, Calverley TA, Stacey BS, Rose G, Fall L, Tsukamoto H, Jones G, Corkill R, Tuaillon E, Hirtz C, Lehmann S, Marchi N, Marley CJ, Bailey DM. Concussion history in rugby union players is associated with depressed cerebrovascular reactivity and cognition. Scand J Med Sci Sports 2021; 31:2291-2299. [PMID: 34487582 DOI: 10.1111/sms.14046] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 08/24/2021] [Accepted: 09/03/2021] [Indexed: 01/06/2023]
Abstract
Recurrent contact and concussion in rugby union remains a significant public health concern given the potential increased risk of neurodegeneration in later life. This study determined to what extent prior-recurrent contact impacts molecular-hemodynamic biomarkers underpinning cognition in current professional rugby union players with a history of concussion. Measurements were performed in 20 professional rugby union players with an average of 16 (interquartile range [IQR] 13-19) years playing history reporting 3 (IQR 1-4) concussions. They were compared to 17 sex-age-physical activity-and education-matched non-contact controls with no prior history of self-reported concussion. Venous blood was assayed directly for the ascorbate free radical (A•- electron paramagnetic resonance spectroscopy) nitric oxide metabolites (NO reductive ozone-based chemiluminescence) and select biomarkers of neurovascular unit integrity (NVU chemiluminescence/ELISA). Middle cerebral artery blood flow velocity (MCAv doppler ultrasound) was employed to determine basal perfusion and cerebrovascular reactivity (CVR) to hyper/hypocapnia ( CVR CO 2 Hyper / Hypo ). Cognition was assessed by neuropsychometric testing. Elevated systemic oxidative-nitrosative stress was confirmed in the players through increased A•- (p < 0.001) and suppression of NO bioavailability (p < 0.001). This was accompanied by a lower CVR range ( CVR CO 2 Range ; p = 0.045) elevation in neurofilament light-chain (p = 0.010) and frontotemporal impairments in immediate-memory (p = 0.001) delayed-recall (p = 0.048) and fine-motor coordination (p < 0.001). Accelerated cognitive decline subsequent to prior-recurrent contact and concussion history is associated with a free radical-mediated suppression of CVR and neuronal injury providing important mechanistic insight that may help better inform clinical management.
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Affiliation(s)
- Thomas S Owens
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, UK
| | - Thomas A Calverley
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, UK
| | - Benjamin S Stacey
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, UK
| | - George Rose
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, UK
| | - Lewis Fall
- Faculty of Computing, Engineering and Science, University of South Wales, Pontypridd, UK
| | - Hayato Tsukamoto
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, UK.,Faculty of Sport and Health Science, Ritsumeikan University, Shiga, Japan
| | - Gareth Jones
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, UK
| | - Robin Corkill
- Department of Neurology, University Hospital of Wales, Cardiff, UK
| | - Edouard Tuaillon
- Department of Infectious Diseases, University of Montpellier, INSERM, Montpellier, France
| | - Christophe Hirtz
- University of Montpellier, CHU of Montpellier, INSERM, Montpellier, France
| | - Sylvain Lehmann
- University of Montpellier, CHU of Montpellier, INSERM, Montpellier, France
| | - Nicola Marchi
- Laboratory of Cerebrovascular and Glia Research, Department of Neuroscience, Institute of Functional Genomics, University of Montpellier, Montpellier, France
| | - Christopher J Marley
- 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
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11
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Owens TS, Calverley TA, Stacey BS, Iannatelli A, Venables L, Rose G, Fall L, Tsukamoto H, Berg RMG, Jones GL, Marley CJ, Bailey DM. Contact events in rugby union and the link to reduced cognition: evidence for impaired redox-regulation of cerebrovascular function. Exp Physiol 2021; 106:1971-1980. [PMID: 34355451 DOI: 10.1113/ep089330] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 07/13/2021] [Indexed: 01/25/2023]
Abstract
NEW FINDINGS What is the central question of this study? How does recurrent contact incurred across a season of professional rugby union impact molecular, cerebrovascular and cognitive function? What is the main findings and its importance? A single season of professional rugby union increases systemic oxidative-nitrosative stress (OXNOS) confirmed by a free radical-mediated suppression in nitric oxide bioavailability. Forwards encountered a higher frequency of contact events compared to backs, exhibiting elevated OXNOS and lower cerebrovascular function and cognition. Collectively, these findings provide mechanistic insight into the possible cause of reduced cognition in rugby union subsequent to impairment in the redox regulation of cerebrovascular function. ABSTRACT Contact events in rugby union remain a public health concern. We determined the molecular, cerebrovascular and cognitive consequences of contact events during a season of professional rugby. Twenty-one male players aged 25 (mean) ± 4 (SD) years were recruited from a professional rugby team comprising forwards (n = 13) and backs (n = 8). Data were collected across the season. Pre- and post-season, venous blood was assayed for the ascorbate free radical (A•- , electron paramagnetic resonance spectroscopy) and nitric oxide (NO, reductive ozone-based chemiluminescence) to quantify oxidative-nitrosative stress (OXNOS). Middle cerebral artery velocity (MCAv, Doppler ultrasound) was measured to assess cerebrovascular reactivity (CVR), and cognition was assessed using the Montreal Cognitive Assessment (MoCA). Notational analysis determined contact events over the season. Forwards incurred more collisions (Mean difference [MD ] 7.49; 95% CI, 2.58-12.40; P = 0.005), tackles (MD 3.49; 95% CI, 0.42-6.56; P = 0.028) and jackals (MD 2.21; 95% CI, 0.18-4.24; P = 0.034). Forwards suffered five concussions while backs suffered one concussion. An increase in systemic OXNOS, confirmed by elevated A•- (F2,19 = 10.589, P = 0.004) and corresponding suppression of NO bioavailability (F2,19 = 11.492, P = 0.003) was apparent in forwards and backs across the season. This was accompanied by a reduction in cerebral oxygen delivery ( c D O 2 , F2,19 = 9.440, P = 0.006) and cognition (F2,19 = 4.813, P = 0.041). Forwards exhibited a greater decline in the cerebrovascular reactivity range to changes in PETCO2 ( CV R C O 2 RANG compared to backs (MD 1.378; 95% CI, 0.74-2.02; P < 0.001).
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Affiliation(s)
- Thomas S Owens
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, UK
| | - Thomas A Calverley
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, UK
| | - Benjamin S Stacey
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, UK
| | - Angelo Iannatelli
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, UK
| | - Lucy Venables
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, UK
| | - George Rose
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, UK
| | - Lewis Fall
- Faculty of Computing, Engineering and Science, University of South Wales, Pontypridd, UK
| | - Hayato Tsukamoto
- Faculty of Sport and Health Science, Ritsumeikan University, Shiga, Japan
| | - Ronan M G Berg
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Gareth L Jones
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, UK
| | - Christopher J Marley
- 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
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12
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García-Carpintero S, Domínguez-Bértalo J, Pedrero-Prieto C, Frontiñán-Rubio J, Amo-Salas M, Durán-Prado M, García-Pérez E, Vaamonde J, Alcain FJ. Ubiquinol Supplementation Improves Gender-Dependent Cerebral Vasoreactivity and Ameliorates Chronic Inflammation and Endothelial Dysfunction in Patients with Mild Cognitive Impairment. Antioxidants (Basel) 2021; 10:143. [PMID: 33498250 PMCID: PMC7909244 DOI: 10.3390/antiox10020143] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 01/11/2021] [Accepted: 01/14/2021] [Indexed: 12/13/2022] Open
Abstract
Ubiquinol can protect endothelial cells from multiple mechanisms that cause endothelial damage and vascular dysfunction, thus contributing to dementia. A total of 69 participants diagnosed with mild cognitive impairment (MCI) received either 200 mg/day ubiquinol (Ub) or placebo for 1 year. Cognitive assessment of patients was performed at baseline and after 1 year of follow-up. Patients' cerebral vasoreactivity was examined using transcranial Doppler sonography, and levels of Ub and lipopolysaccharide (LPS) in plasma samples were quantified. Cell viability and necrotic cell death were determined using the microvascular endothelial cell line bEnd3. Coenzyme Q10 (CoQ) levels increased in patients supplemented for 1 year with ubiquinol versus baseline and the placebo group, although higher levels were observed in male patients. The higher cCoQ concentration in male patients improved cerebral vasoreactivity CRV and reduced inflammation, although the effect of Ub supplementation on neurological improvement was negligible in this study. Furthermore, plasma from Ub-supplemented patients improved the viability of endothelial cells, although only in T2DM and hypertensive patients. This suggests that ubiquinol supplementation could be recommended to reach a concentration of 5 μg/mL in plasma in MCI patients as a complement to conventional treatment.
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Affiliation(s)
- Sonia García-Carpintero
- Department of Medical Sciences, Faculty of Medicine, University of Castilla-La Mancha, 13071 Ciudad Real, Spain; (S.G.-C.); (C.P.-P.); (J.F.-R.)
- Oxidative Stress and Neurodegeneration Group, Regional Centre for Biomedical Research, University of Castilla-La Mancha, 13071 Ciudad Real, Spain
| | - Javier Domínguez-Bértalo
- Neurology Department, Virgen de Altagracia Hospital—Manzanares, SESCAM, 13002 Manzanares, Spain;
| | - Cristina Pedrero-Prieto
- Department of Medical Sciences, Faculty of Medicine, University of Castilla-La Mancha, 13071 Ciudad Real, Spain; (S.G.-C.); (C.P.-P.); (J.F.-R.)
- Oxidative Stress and Neurodegeneration Group, Regional Centre for Biomedical Research, University of Castilla-La Mancha, 13071 Ciudad Real, Spain
| | - Javier Frontiñán-Rubio
- Department of Medical Sciences, Faculty of Medicine, University of Castilla-La Mancha, 13071 Ciudad Real, Spain; (S.G.-C.); (C.P.-P.); (J.F.-R.)
- Oxidative Stress and Neurodegeneration Group, Regional Centre for Biomedical Research, University of Castilla-La Mancha, 13071 Ciudad Real, Spain
| | - Mariano Amo-Salas
- Department of Mathematics, Faculty of Medicine, University of Castilla-La Mancha, 13071 Ciudad Real, Spain;
| | - Mario Durán-Prado
- Department of Medical Sciences, Faculty of Medicine, University of Castilla-La Mancha, 13071 Ciudad Real, Spain; (S.G.-C.); (C.P.-P.); (J.F.-R.)
- Oxidative Stress and Neurodegeneration Group, Regional Centre for Biomedical Research, University of Castilla-La Mancha, 13071 Ciudad Real, Spain
| | - Eloy García-Pérez
- Neurology Department, General University Hospital—Ciudad Real, SESCAM, 13005 Ciudad Real, Spain;
| | - Julia Vaamonde
- Department of Medical Sciences, Faculty of Medicine, University of Castilla-La Mancha, 13071 Ciudad Real, Spain; (S.G.-C.); (C.P.-P.); (J.F.-R.)
- Neurology Department, General University Hospital—Ciudad Real, SESCAM, 13005 Ciudad Real, Spain;
| | - Francisco J. Alcain
- Department of Medical Sciences, Faculty of Medicine, University of Castilla-La Mancha, 13071 Ciudad Real, Spain; (S.G.-C.); (C.P.-P.); (J.F.-R.)
- Oxidative Stress and Neurodegeneration Group, Regional Centre for Biomedical Research, University of Castilla-La Mancha, 13071 Ciudad Real, Spain
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13
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Hori D, Nomura Y, Nakano M, Akiyoshi K, Kimura N, Yamaguchi A. Relationship between endothelial function and vascular stiffness on lower limit of cerebral autoregulation in patients undergoing cardiovascular surgery. Artif Organs 2020; 45:382-389. [PMID: 33191501 DOI: 10.1111/aor.13868] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 09/29/2020] [Indexed: 01/02/2023]
Abstract
Hemodynamic management based on cerebral autoregulation range is a possible strategy for preserving major organ perfusion during cardiovascular surgery. The purpose of this study was to evaluate the relation of vascular properties with lower limit of cerebral autoregulation (LLA). LLA was monitored in 66 patients undergoing cardiovascular surgery using near-infrared spectroscopy. To determine the clinical importance of LLA monitoring, association of blood pressure excursions below LLA and acute kidney injury (AKI) was evaluated. Flow-mediated dilation (FMD) and pulse wave velocity (PWV) were measured for the evaluation of endothelial function and aortic stiffness. Variables associated with LLA were evaluated. Excluding patients on hemodialysis, there were 15 patients (25.9%) who developed AKI. Blood pressure excursions below LLA were higher in patients who developed AKI (4.55 mm Hg × hr vs. 1.23 mm Hg × hr, P = .017). In the univariate analysis, prevalence of ischemic heart disease (No IHD: 53 ± 13.0 mm Hg vs. IHD: 60.0 ± 13.6 mm Hg, P = .056) and FMD (r = -0.42, 95% CI -0.61 to -0.19, P < .001) were associated with LLA before cardiopulmonary bypass (CPB). During CPB, calcium channel blocker (No Ca blocker: 42 ± 10.6 mm Hg vs. Ca blocker: 49 ± 14.3 mm Hg, P = .033), diabetes (no DM: 44 ± 13.2 mm Hg vs. DM: 55 ± 10.0 mm Hg, P = .024), FMD (r = -0.32, 95% CI -0.55 to -0.05, P = .021), and PWV (r = 0.28, 95% CI 0.012 to 0.513, P = .041) were associated with LLA. Multivariate analysis showed that FMD was correlated with LLA before CPB (r = -2.19, 95% CI -3.621 to -0.755, P = .003), while PWV was correlated with LLA during CPB (r = 0.01, 95% CI 0.001-0.019, P = .023). Endothelial function and aortic stiffness may be important factors in determining LLA at different phases in cardiovascular surgery.
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Affiliation(s)
- Daijiro Hori
- Department of Cardiovascular Surgery, Saitama Medical Center, Jichi Medical University, Saitama, Japan
| | - Yohei Nomura
- Department of Cardiovascular Surgery, Saitama Medical Center, Jichi Medical University, Saitama, Japan
| | - Mitsunori Nakano
- Department of Cardiovascular Surgery, Saitama Medical Center, Jichi Medical University, Saitama, Japan
| | - Kei Akiyoshi
- Department of Cardiovascular Surgery, Saitama Medical Center, Jichi Medical University, Saitama, Japan
| | - Naoyuki Kimura
- Department of Cardiovascular Surgery, Saitama Medical Center, Jichi Medical University, Saitama, Japan
| | - Atsushi Yamaguchi
- Department of Cardiovascular Surgery, Saitama Medical Center, Jichi Medical University, Saitama, Japan
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14
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Gratton G, Weaver SR, Burley CV, Low KA, Maclin EL, Johns PW, Pham QS, Lucas SJE, Fabiani M, Rendeiro C. Dietary flavanols improve cerebral cortical oxygenation and cognition in healthy adults. Sci Rep 2020; 10:19409. [PMID: 33235219 PMCID: PMC7687895 DOI: 10.1038/s41598-020-76160-9] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 10/08/2020] [Indexed: 12/22/2022] Open
Abstract
Cocoa flavanols protect humans against vascular disease, as evidenced by improvements in peripheral endothelial function, likely through nitric oxide signalling. Emerging evidence also suggests that flavanol-rich diets protect against cognitive aging, but mechanisms remain elusive. In a randomized double-blind within-subject acute study in healthy young adults, we link these two lines of research by showing, for the first time, that flavanol intake leads to faster and greater brain oxygenation responses to hypercapnia, as well as higher performance only when cognitive demand is high. Individual difference analyses further show that participants who benefit from flavanols intake during hypercapnia are also those who do so in the cognitive challenge. These data support the hypothesis that similar vascular mechanisms underlie both the peripheral and cerebral effects of flavanols. They further show the importance of studies combining physiological and graded cognitive challenges in young adults to investigate the actions of dietary flavanols on brain function.
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Affiliation(s)
- Gabriele Gratton
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Psychology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Samuel R Weaver
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Claire V Burley
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Kathy A Low
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Edward L Maclin
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Paul W Johns
- Abbott-Nutrition Division, Research and Development, 3300 Stelzer Road, Columbus, OH, 43219, USA
| | - Quang S Pham
- Abbott-Nutrition Division, Research and Development, 3300 Stelzer Road, Columbus, OH, 43219, USA
| | - Samuel J E Lucas
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, B15 2TT, UK
- Centre for Human Brain Health, University of Birmingham, Birmingham, UK
| | - Monica Fabiani
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Psychology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Catarina Rendeiro
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, B15 2TT, UK.
- Centre for Human Brain Health, University of Birmingham, Birmingham, UK.
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15
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Robertson AD, Papadhima I, Edgell H. Sex differences in the autonomic and cerebrovascular responses to upright tilt. Auton Neurosci 2020; 229:102742. [PMID: 33197693 DOI: 10.1016/j.autneu.2020.102742] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 10/30/2020] [Accepted: 11/02/2020] [Indexed: 01/11/2023]
Abstract
Sex differences in the regulation of autonomic and cerebrovascular responses to orthostatic stress remain unclear. The objectives of this study were to concurrently investigate autonomic control and cerebrovascular resistance indices, including critical closing pressure (CrCP) and resistance area product (RAP), during upright tilt in men and women. In 13 women and 14 men (18-29 years), ECG, non-invasive blood pressure, middle cerebral artery blood velocity, and end-tidal CO2 (ETCO2) were continuously measured during supine rest and 70° tilt. Heart rate variability (HRV), cardiovagal baroreflex sensitivity (cBRS), and transfer function parameters of dynamic cerebral autoregulation were calculated. Compared to supine, upright tilt increased the low frequency-to-high frequency ratio of HRV in men only (P = 0.044), and decreased cBRS more in women (P = 0.001). Cerebrovascular resistance index (CVRi) increased during tilt only in men (sex-by-time interaction: P = 0.004). RAP was lower in women throughout tilt (main effect of sex: P = 0.022). CrCP decreased during tilt in both sexes (main effect of time: P < 0.001). Normalizing to ETCO2 did not alter the effect of tilt on cerebrovascular resistance. Men displayed a greater increase of sympathetic indices and CVRi during tilt while women had greater parasympathetic withdrawal. We hypothesize that increased sympathetic activity in men may drive sex differences in the cerebrovascular response to upright posture.
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Affiliation(s)
- Andrew D Robertson
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada; Schlegel-UW Research Institute for Aging, University of Waterloo, Waterloo, Ontario, Canada
| | - Ismina Papadhima
- School of Kinesiology and Health Sciences, York University, Toronto, Ontario, Canada
| | - Heather Edgell
- School of Kinesiology and Health Sciences, York University, Toronto, Ontario, Canada; Muscle Health Research Centre, York University, Toronto, Ontario, Canada.
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16
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Ezra M, Garry P, Rowland MJ, Mitsis GD, Pattinson KT. Phase dynamics of cerebral blood flow in subarachnoid haemorrhage in response to sodium nitrite infusion. Nitric Oxide 2020; 106:55-65. [PMID: 33283760 DOI: 10.1016/j.niox.2020.10.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 10/08/2020] [Accepted: 10/18/2020] [Indexed: 11/25/2022]
Abstract
Aneurysmal subarachnoid haemorrhage (SAH) is a devastating subset of stroke. One of the major determinates of morbidity is the development of delayed cerebral ischemia (DCI). Disruption of the nitric oxide (NO) pathway and consequently the control of cerebral blood flow (CBF), known as cerebral autoregulation, is believed to play a role in its pathophysiology. Through the pharmacological manipulation of in vivo NO levels using an exogenous NO donor we sought to explore this relationship. Phase synchronisation index (PSI), an expression of the interdependence between CBF and arterial blood pressure (ABP) and thus cerebral autoregulation, was calculated before and during sodium nitrite administration in 10 high-grade SAH patients acutely post-rupture. In patients that did not develop DCI, there was a significant increase in PSI around 0.1 Hz during the administration of sodium nitrite (33%; p-value 0.006). In patients that developed DCI, PSI did not change significantly. Synchronisation between ABP and CBF at 0.1 Hz has been proposed as a mechanism by which organ perfusion is maintained, during periods of physiological stress. These findings suggest that functional NO depletion plays a role in impaired cerebral autoregulation following SAH, but the development of DCI may have a distinct pathophysiological aetiology.
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Affiliation(s)
- Martyn Ezra
- Nuffield Division of Anaesthetics, Nuffield Department of Clinical Neurosciences, University of Oxford, UK.
| | - Payashi Garry
- Nuffield Division of Anaesthetics, Nuffield Department of Clinical Neurosciences, University of Oxford, UK
| | - Matthew J Rowland
- Nuffield Division of Anaesthetics, Nuffield Department of Clinical Neurosciences, University of Oxford, UK
| | | | - Kyle Ts Pattinson
- Nuffield Division of Anaesthetics, Nuffield Department of Clinical Neurosciences, University of Oxford, UK
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17
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Appleton JP, Krishnan K, Bath PM. Transdermal delivery of glyceryl trinitrate: clinical applications in acute stroke. Expert Opin Drug Deliv 2020; 17:297-303. [PMID: 31973594 DOI: 10.1080/17425247.2020.1716727] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Introduction: Glyceryl trinitrate (GTN), a nitric oxide donor, is a candidate treatment for the management of acute stroke with hemodynamic and potential reperfusion and neuroprotective effects.Areas covered: Here we discuss the evidence to date from clinical trials and present and future possibilities for the clinical application of transdermal GTN in acute stroke. When administered as a transdermal patch during the acute and subacute phases after stroke, GTN was safe, lowered blood pressure, maintained cerebral blood flow, and did not induce cerebral steal or alter functional outcome. However, when given within the hyperacute phase (<6 h of stroke onset), GTN reduced death and dependency, death, disability, cognitive impairment, and mood disturbance, and improved quality of life. However, in a large prehospital trial with treatment within 4 h, GTN did not influence clinical outcomes.Expert opinion: Transdermal GTN is an easy to administer BP-lowering therapy, which is safe when given after 2 h of stroke onset, may improve outcome when initiated within 2-6 h, but should be avoided (outside of a clinical trial) in the ultra-acute period within 2 h of stroke onset. Further research needs to investigate the mechanisms of benefit or harm in ultra/hyperacute stroke patients.
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Affiliation(s)
- Jason P Appleton
- Stroke Trials Unit, Division of Clinical Neuroscience, University of Nottingham, Nottingham, UK.,Neurology, University Hospitals Birmingham NHS Foundation Trust, Edgbaston, Birmingham, UK
| | - Kailash Krishnan
- Stroke Trials Unit, Division of Clinical Neuroscience, University of Nottingham, Nottingham, UK.,Stroke, Nottingham University Hospitals NHS Trust, Nottingham, UK
| | - Philip M Bath
- Stroke Trials Unit, Division of Clinical Neuroscience, University of Nottingham, Nottingham, UK.,Stroke, Nottingham University Hospitals NHS Trust, Nottingham, UK
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18
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Cárdenas D, Madinabeitia I, Vera J, de Teresa C, Alarcón F, Jiménez R, Catena A. Better brain connectivity is associated with higher total fat mass and lower visceral adipose tissue in military pilots. Sci Rep 2020; 10:610. [PMID: 31953480 PMCID: PMC6969099 DOI: 10.1038/s41598-019-57345-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 12/23/2019] [Indexed: 12/17/2022] Open
Abstract
A lack of exercise leads to being overweight or obese affecting regional brain structure and functional connectivity associated with impaired cognitive function and dementia. In recent decades, several studies of healthy individuals suggest that adiposity may also produce negative independent effects on the brain. We aimed to investigate the relationship between body composition – total fat mass (TFM) and visceral adipose tissue (VAT) – with white matter (WM) integrity using a whole-brain approach in military pilots. Twenty-three military helicopter pilots (Mage = 36.79; SD = 8.00; MBMI = 25.48; SD = 2.49) took part in the study. Brain volumes were studied using diffusion tensor imaging technique by means of a 3T Magnetom Tim Trio. Measurements of body mass index (BMI), TFM and VAT were obtained using Dual-energy X-ray Absorptiometry (DXA). The results showed that, on one hand, higher TFM was associated with higher white matter fractional anisotropy (FA) and, on the other hand, higher VAT was associated with lower FA. Data showed that TFM and VAT are the critical factors underlying WM integrity in combat helicopter pilots. The authors suggest that fat presence enhance brain connectivity while there is no excess, specifically in VAT.
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Affiliation(s)
- David Cárdenas
- Department of Physical Education and Sport, Faculty of Sport Sciences, University of Granada, Granada, Spain. .,Sport and Health University Research Institute (iMUDS), Granada, Spain.
| | - Iker Madinabeitia
- Department of Physical Education and Sport, Faculty of Sport Sciences, University of Granada, Granada, Spain.,Sport and Health University Research Institute (iMUDS), Granada, Spain
| | - Jesús Vera
- Sport and Health University Research Institute (iMUDS), Granada, Spain.,Department of Optics, Faculty of Sciences, University of Granada, Granada, Spain
| | - Carlos de Teresa
- Sport and Health University Research Institute (iMUDS), Granada, Spain.,Andalusian Centre of Sports Medicine, Consejería de Turismo y Deporte, Junta de Andalucía, Granada, Spain
| | - Francisco Alarcón
- Department of Didactic General and Specific Training, Faculty of Education, University of Alicante, Alicante, Spain
| | - Raimundo Jiménez
- Sport and Health University Research Institute (iMUDS), Granada, Spain.,Department of Optics, Faculty of Sciences, University of Granada, Granada, Spain
| | - Andrés Catena
- Department of Experimental Psychology, Faculty of Psychology, University of Granada, Granada, Spain.,Mind, Brain and Behaviour Research Centre (CIMCYC), University of Granada, Granada, Spain
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19
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Marmarelis VZ, Shin DC, Oesterreich M, Mueller M. Quantification of dynamic cerebral autoregulation and CO 2 dynamic vasomotor reactivity impairment in essential hypertension. J Appl Physiol (1985) 2020; 128:397-409. [PMID: 31917625 DOI: 10.1152/japplphysiol.00620.2019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The study of dynamic cerebral autoregulation (DCA) in essential hypertension has received considerable attention because of its clinical importance. Several studies have examined the dynamic relationship between spontaneous beat-to-beat arterial blood pressure data and contemporaneous cerebral blood flow velocity measurements (obtained via transcranial Doppler at the middle cerebral arteries) in the form of a linear input-output model using transfer function analysis. This analysis is more reliable when the contemporaneous effects of changes in blood CO2 tension are also taken into account, because of the significant effects of CO2 dynamic vasomotor reactivity (DVR) upon cerebral flow. In this article, we extract such input-output predictive models from spontaneous time series hemodynamic data of 24 patients with essential hypertension and 20 normotensive control subjects under resting conditions, using the novel methodology of principal dynamic modes (PDMs) that achieves improved estimation accuracy over previous methods for relatively short and noisy data. The obtained data-based models are subsequently used to compute indexes and markers that quantify DCA and DVR in each subject or patient and therefore can be used to assess the effects of essential hypertension. These model-based DCA and DVR indexes were properly defined to capture the observed effects of DCA and VR and found to be significantly different (P < 0.05) in the hypertensive patients. We also found significant differences between patients and control subjects in the relative contribution of three PDMs to the model output prediction, a finding that offers the prospect of identifying the physiological mechanisms affected by essential hypertension when the PDMs are interpreted in terms of specific physiological mechanisms.NEW & NOTEWORTHY This article presents novel model-based methodology for obtaining diagnostic indexes of dynamic cerebral autoregulation and dynamic vasomotor reactivity in hypertension.
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Affiliation(s)
- Vasilis Z Marmarelis
- Biomedical Simulations Resource Center, University of Southern California, Los Angeles, California
| | - Dae C Shin
- Biomedical Simulations Resource Center, University of Southern California, Los Angeles, California
| | | | - Martin Mueller
- Neurocenter, Luzerner Kantonsspital, Lucerne, Switzerland
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20
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21
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Shoemaker LN, Wilson LC, Lucas SJE, Machado L, Cotter JD. Cerebrovascular regulation is not blunted during mental stress. Exp Physiol 2019; 104:1678-1687. [PMID: 31465595 DOI: 10.1113/ep087832] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Accepted: 08/22/2019] [Indexed: 01/08/2023]
Abstract
NEW FINDINGS What is the central question of the study? What are the effects of acute mental stress on the mechanisms regulating cerebral blood flow? What is the main finding and its importance? The major new findings are as follows: (i) high mental stress and hypercapnia had an interactive effect on mean middle cerebral artery blood velocity; (ii) high mental stress altered the regulation of cerebral blood flow; (iii) the increased cerebrovascular hypercapnic reactivity was not driven by changes in mean arterial pressure alone; and (iv) this increased perfusion with mental stress appeared not to be justified functionally by an increase in oxygen demand (as determined by near-infrared spectroscopy-derived measures). ABSTRACT In this study, we examined the effects of acute mental stress on cerebrovascular function. Sixteen participants (aged 23 ± 4 years; five female) were exposed to low and high mental stress using simple arithmetic (counting backwards from 1000) and more complex arithmetic (serial subtraction of 13 from a rapidly changing four-digit number), respectively. During consecutive conditions of baseline, low stress and high stress, end-tidal partial pressure of CO2 ( P ET , C O 2 ) was recorded at normocapnia (37 ± 3 mmHg) and clamped at two elevated levels (P < 0.01): 41 ± 1 and 46 ± 1 mmHg. Mean right middle cerebral artery blood velocity (MCAvmean ; transcranial Doppler ultrasound), right prefrontal cortex haemodynamics (near-infrared spectroscopy) and mean arterial blood pressure (MAP; finger photoplethysmography) were measured continuously. Cerebrovascular hypercapnic reactivity (ΔMCAvmean /Δ P ET , C O 2 ), cerebrovascular conductance (CVC; MCAvmean /MAP), CVC CO2 reactivity (ΔCVC/Δ P ET , C O 2 ) and total peripheral resistance (MAP/cardiac output) were calculated. Acute high mental stress increased MCAvmean by 7 ± 7%, and more so at higher P ET , C O 2 (32 ± 10%; interaction, P = 0.03), illustrating increased sensitivity to CO2 (i.e. its major regulator). High mental stress also increased MAP (17 ± 9%; P ≤ 0.01), coinciding with increased near-infrared spectroscopy-derived prefrontal haemoglobin volume and saturation measures. High mental stress elevated both cerebrovascular hypercapnic and conductance reactivities (main effect of stress, P ≤ 0.04). These findings indicate that the cerebrovascular response to acute high mental stress results in a coordinated regulation between multiple processes.
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Affiliation(s)
- Leena N Shoemaker
- School of Physical Education, Sport and Exercise Sciences, University of Otago, Dunedin, New Zealand
| | - Luke C Wilson
- Department of Medicine, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Samuel J E Lucas
- Department of Physiology, University of Otago, Dunedin, New Zealand.,School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, UK.,Centre for Human Brain Health, University of Birmingham, Birmingham, UK
| | - Liana Machado
- Department of Psychology, University of Otago, Dunedin, New Zealand
| | - James D Cotter
- School of Physical Education, Sport and Exercise Sciences, University of Otago, Dunedin, New Zealand
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22
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Chow FC, Wang H, Li Y, Mehta N, Hu Y, Han Y, Xie J, Lu W, Xu W, Li T. Cerebral Vasoreactivity Evaluated by the Breath-Holding Challenge Correlates With Performance on a Cognitive Screening Test in Persons Living With Treated HIV Infection in China. J Acquir Immune Defic Syndr 2019; 79:e101-e104. [PMID: 29995703 DOI: 10.1097/qai.0000000000001805] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Felicia C Chow
- Department of Neurology, Division of Infectious Diseases, University of California, San Francisco and Zuckerberg San Francisco General Hospital, San Francisco, CA.,Weill Institute for Neurosciences, University of California, San Francisco, CA
| | - Huanling Wang
- Department of Infectious Diseases, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China.,Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Yanling Li
- Department of Infectious Diseases, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China.,Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Natasha Mehta
- Institute for Global Health Sciences, University of California, San Francisco, CA
| | - Yinghuan Hu
- Department of Neurology, Peking Union Medical College Hospital, Beijing, China
| | - Yang Han
- Department of Infectious Diseases, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China.,Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Jing Xie
- Department of Infectious Diseases, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China.,Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Wei Lu
- Department of Infectious Diseases, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China.,Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Weihai Xu
- Department of Neurology, Peking Union Medical College Hospital, Beijing, China
| | - Taisheng Li
- Department of Infectious Diseases, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China.,Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
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23
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Rasmussen PM, Aamand R, Weitzberg E, Christiansen M, Østergaard L, Lund TE. APOE gene-dependent BOLD responses to a breath-hold across the adult lifespan. NEUROIMAGE-CLINICAL 2019; 24:101955. [PMID: 31408838 PMCID: PMC6699560 DOI: 10.1016/j.nicl.2019.101955] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 06/21/2019] [Accepted: 07/19/2019] [Indexed: 11/03/2022]
Abstract
Age and apolipoprotein E (APOE) e4 genotype are two of the strongest known risk factors for sporadic Alzheimer's disease (AD). Neuroimaging has shown hemodynamic response changes with age, in asymptomatic carriers of the APOE e4 allele, and in AD. In this study, we aimed to characterize and differentiate age- and APOE gene-specific hemodynamic changes to breath-hold and visual stimulation. A further aim was to study whether these responses were modulated by 3-day intake of nitrate, a nitric oxide (NO) source. The study was designed as a randomized, double-blinded, placebo-controlled crossover study, and the study cohort comprised 41 APOE e4 carriers (e3/e4 or e4/e4 genotype) and 40 non-carriers (e3/e3 genotype) aged 30-70 years at enrollment. The participants underwent two scanning sessions, each preceded by ingestion of sodium nitrate or sodium chloride (control). During functional magnetic resonance imaging (fMRI) sessions, participants performed two concurrent tasks; a breath-hold task to probe cerebrovascular reactivity and a visual stimulation task to evoke functional hyperemia, respectively. We found that the blood oxygenation level dependent (BOLD) hemodynamic response to breath-hold was altered in APOE e4 carriers relative to non-carriers. Mid-aged (50-60 years of age) e4 carriers exhibited a significantly increased peak time relative to mid-aged e3 carriers, and peak time for younger (30-40 years of age) e4 carriers was significantly shorter than that of mid-aged e4 carriers. The response width was significantly increased for e4 carriers. The response peak magnitude significantly decreased with age. For the visual stimulation task, we found age-related changes, with reduced response magnitude with age but no significant effect of APOE allele type. We found no effect of nitrate ingestion on BOLD responses evoked by the breath-hold and visual stimulation tasks. The APOE gene-dependent response to breath-hold may reflect NO-independent differences in vascular function.
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Affiliation(s)
- Peter M Rasmussen
- Center of Functionally Integrative Neuroscience, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.
| | - Rasmus Aamand
- Center of Functionally Integrative Neuroscience, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Eddie Weitzberg
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Michael Christiansen
- Department for Congenital Disorders, Statens Serum Institut, Copenhagen, Denmark
| | - Leif Østergaard
- Center of Functionally Integrative Neuroscience, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Torben E Lund
- Center of Functionally Integrative Neuroscience, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
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24
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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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25
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Purkayastha S, Sorond FA, Lyng S, Frantz J, Murphy MN, Hynan LS, Sabo T, Bell KR. Impaired Cerebral Vasoreactivity Despite Symptom Resolution in Sports-Related Concussion. J Neurotrauma 2019; 36:2385-2390. [PMID: 30693827 DOI: 10.1089/neu.2018.5861] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Traumatic brain injury (TBI) is associated with increased risk of later-life neurodegeneration and dementia. However, the underpinning mechanisms are poorly understood, and secondary injury resulting from perturbed physiological processes plays a significant role. Cerebral vasoreactivity (CVR), a measure of hemodynamic reserve, is known to be impaired in TBI. However, the temporal course of this physiological perturbation is not established. We examined CVR and clinical symptoms on day 3 (T1), day 21 (T2), and day 90 (T3) after concussion in collegiate athletes and cross-sectionally in non-injured controls. Changes in middle cerebral artery blood flow velocity (MCAV; transcranial Doppler ultrasonography) were measured during changes in end-tidal CO2 (PetCO2) at normocapnia, hypercapnia (inspiring 8% CO2), and hypocapnia (hyperventilation). CVR was determined as the slope of the linear relationship and expressed as percent change in MCAV per mmHg change in PetCO2. CVR was attenuated during the acute phase T1 (1.8 ± 0.4U; p = 0.0001), subacute phases T2 (2.0 ± 0.4U; p = 0.0017), and T3 (1.9 ± 0.6U; p = 0.023) post-concussion compared to the controls (2.3 ± 0.3U). Concussed athletes exhibited higher symptom number (2.5 ± 3.0 vs. 12.1 ± 7.0; p < 0.0001) and severity (4.2 ± 6.0 vs. 29.5 ± 23.0; p < 0.0001), higher Patient Health Questionnaire-9 score (2.2 ± 2.0 vs. 9.1 ± 6.0; p = 0.0003) at T1. However, by T2, symptoms had resolved. We show that CVR is impaired as early as 4 days and remains impaired up to 3 months post-injury despite symptom resolution. Persistent perturbations in CVR may therefore be involved in secondary injury. Future studies with a larger sample size and longer follow-up period are needed to validate this finding and delineate the duration of this vulnerable period.
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Affiliation(s)
- Sushmita Purkayastha
- 1Department of Applied Physiology and Wellness, Simmons School of Education and Human Development, Southern Methodist University, Dallas, Texas.,2Department of Physical Medicine and Rehabilitation, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Farzaneh A Sorond
- 3Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Sydney Lyng
- 1Department of Applied Physiology and Wellness, Simmons School of Education and Human Development, Southern Methodist University, Dallas, Texas
| | - Justin Frantz
- 1Department of Applied Physiology and Wellness, Simmons School of Education and Human Development, Southern Methodist University, Dallas, Texas
| | - Megan N Murphy
- 1Department of Applied Physiology and Wellness, Simmons School of Education and Human Development, Southern Methodist University, Dallas, Texas
| | - Linda S Hynan
- 4Department of Clinical Science and Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Tonia Sabo
- 5Department of Pediatrics/Division of Pediatric Neurology & Pain Management, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Kathleen R Bell
- 2Department of Physical Medicine and Rehabilitation, University of Texas Southwestern Medical Center, Dallas, Texas
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26
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Rivera-Lara L. The role of impaired brain perfusion in septic encephalopathy. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2019; 23:54. [PMID: 30782168 PMCID: PMC6381612 DOI: 10.1186/s13054-018-2299-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 12/21/2018] [Indexed: 11/21/2022]
Affiliation(s)
- Lucia Rivera-Lara
- Department of Neurology, The Johns Hopkins University School of Medicine, 600 N Wolfe Street, Phipps 455, Baltimore, MD, 21287, USA. .,Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, 600 N Wolfe Street, Phipps 455, Baltimore, MD, 21287, USA.
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27
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Bailey DM, Brugniaux JV, Filipponi T, Marley CJ, Stacey B, Soria R, Rimoldi SF, Cerny D, Rexhaj E, Pratali L, Salmòn CS, Murillo Jáuregui C, Villena M, Smirl JD, Ogoh S, Pietri S, Scherrer U, Sartori C. Exaggerated systemic oxidative-inflammatory-nitrosative stress in chronic mountain sickness is associated with cognitive decline and depression. J Physiol 2019; 597:611-629. [PMID: 30397919 PMCID: PMC6332753 DOI: 10.1113/jp276898] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 11/05/2018] [Indexed: 12/15/2022] Open
Abstract
KEY POINTS Chronic mountain sickness (CMS) is a maladaptation syndrome encountered at high altitude (HA) characterised by severe hypoxaemia that carries a higher risk of stroke and migraine and is associated with increased morbidity and mortality. We examined if exaggerated oxidative-inflammatory-nitrosative stress (OXINOS) and corresponding decrease in vascular nitric oxide bioavailability in patients with CMS (CMS+) is associated with impaired cerebrovascular function and adverse neurological outcome. Systemic OXINOS was markedly elevated in CMS+ compared to healthy HA (CMS-) and low-altitude controls. OXINOS was associated with blunted cerebral perfusion and vasoreactivity to hypercapnia, impaired cognition and, in CMS+, symptoms of depression. These findings are the first to suggest that a physiological continuum exists for hypoxaemia-induced systemic OXINOS in HA dwellers that when excessive is associated with accelerated cognitive decline and depression, helping identify those in need of more specialist neurological assessment and targeted support. ABSTRACT Chronic mountain sickness (CMS) is a maladaptation syndrome encountered at high altitude (HA) characterised by severe hypoxaemia that carries a higher risk of stroke and migraine and is associated with increased morbidity and mortality. The present cross-sectional study examined to what extent exaggerated systemic oxidative-inflammatory-nitrosative stress (OXINOS), defined by an increase in free radical formation and corresponding decrease in vascular nitric oxide (NO) bioavailability, is associated with impaired cerebrovascular function, accelerated cognitive decline and depression in CMS. Venous blood was obtained from healthy male lowlanders (80 m, n = 17), and age- and gender-matched HA dwellers born and bred in La Paz, Bolivia (3600 m) with (CMS+, n = 23) and without (CMS-, n = 14) CMS. We sampled blood for oxidative (electron paramagnetic resonance spectroscopy, HPLC), nitrosative (ozone-based chemiluminescence) and inflammatory (fluorescence) biomarkers. We employed transcranial Doppler ultrasound to measure cerebral blood flow (CBF) and reactivity. We utilised psychometric tests and validated questionnaires to assess cognition and depression. Highlanders exhibited elevated systemic OXINOS (P < 0.05 vs. lowlanders) that was especially exaggerated in the more hypoxaemic CMS+ patients (P < 0.05 vs. CMS-). OXINOS was associated with blunted cerebral perfusion and vasoreactivity to hypercapnia, impaired cognition and, in CMS+, symptoms of depression. Collectively, these findings are the first to suggest that a physiological continuum exists for hypoxaemia-induced OXINOS in HA dwellers that when excessive is associated with accelerated cognitive decline and depression, helping identify those in need of specialist neurological assessment and support.
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Affiliation(s)
- Damian M. Bailey
- Neurovascular Research LaboratoryFaculty of Life Sciences and Education, University of South WalesUK
| | - Julien V. Brugniaux
- Neurovascular Research LaboratoryFaculty of Life Sciences and Education, University of South WalesUK
- HP2 Laboratory, INSERM U1042Grenoble Alpes UniversityGrenobleFrance
| | - Teresa Filipponi
- Neurovascular Research LaboratoryFaculty of Life Sciences and Education, University of South WalesUK
| | - Christopher J. Marley
- Neurovascular Research LaboratoryFaculty of Life Sciences and Education, University of South WalesUK
| | - Benjamin Stacey
- Neurovascular Research LaboratoryFaculty of Life Sciences and Education, University of South WalesUK
| | - Rodrigo Soria
- Department of Cardiology and Clinical ResearchUniversity HospitalBernSwitzerland
| | - Stefano F. Rimoldi
- Department of Cardiology and Clinical ResearchUniversity HospitalBernSwitzerland
| | - David Cerny
- Department of Cardiology and Clinical ResearchUniversity HospitalBernSwitzerland
| | - Emrush Rexhaj
- Department of Cardiology and Clinical ResearchUniversity HospitalBernSwitzerland
| | | | | | | | | | - Jonathan D. Smirl
- Centre for Heart, Lung and Vascular Health, School of Health and Exercise ScienceUniversity of British Columbia OkanaganKelownaBritish ColumbiaCanada
| | | | | | - Urs Scherrer
- Department of Cardiology and Clinical ResearchUniversity HospitalBernSwitzerland
- Facultad de Ciencias, Departamento de BiologíaUniversidad de TarapacáAricaChile
| | - Claudio Sartori
- Department of Internal MedicineUniversity HospitalUNIL‐LausanneSwitzerland
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28
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Crippa IA, Subirà C, Vincent JL, Fernandez RF, Hernandez SC, Cavicchi FZ, Creteur J, Taccone FS. Impaired cerebral autoregulation is associated with brain dysfunction in patients with sepsis. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2018; 22:327. [PMID: 30514349 PMCID: PMC6280405 DOI: 10.1186/s13054-018-2258-8] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 11/07/2018] [Indexed: 12/12/2022]
Abstract
Background Sepsis-associated brain dysfunction (SABD) is associated with high morbidity and mortality. The pathophysiology of SABD is multifactorial. One hypothesis is that impaired cerebral autoregulation (CAR) may result in brain hypoperfusion and neuronal damage leading to SABD. Methods We studied 100 adult patients with sepsis (July 2012–March 2017) (age = 62 [52–71] years; Acute Physiology and Chronic Health Evaluation II score on admission = 21 [15–26]). Exclusion criteria were acute or chronic intracranial disease, arrhythmias, extracorporeal membrane oxygenation, and known intra- or extracranial supra-aortic vessel disease. The site of infection was predominantly abdominal (46%) or pulmonary (28%). Transcranial Doppler was performed, insonating the left middle cerebral artery with a 2-MHz probe. Middle cerebral artery blood flow velocity (FV) and arterial blood pressure (ABP) signals were recorded simultaneously; Pearson’s correlation coefficient (mean flow index [Mxa]) between ABP and FV was calculated using MATLAB. Impaired CAR was defined as Mxa > 0.3. Results Mxa was 0.29 [0.05–0.62]. CAR was impaired in 50 patients (50%). In a multiple linear regression analysis, low mean arterial pressure, history of chronic kidney disease and fungal infection were associated with high Mxa. SABD was diagnosed in 57 patients (57%). In a multivariable analysis, altered cerebral autoregulation, mechanical ventilation and history of vascular disease were independent predictors of SABD. Conclusions Cerebral autoregulation was altered in half of the patients with sepsis and was associated with the development of SABD. These findings support the concept that cerebral hypoxia could contribute to the development of SABD. Electronic supplementary material The online version of this article (10.1186/s13054-018-2258-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ilaria Alice Crippa
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles (ULB), Route de Lennik, 808, 1070, Brussels, Belgium
| | - Carles Subirà
- Department of Intensive Care, Althaia Xarxa Assistencial Universitària de Manresa, Barcelona, Spain
| | - Jean-Louis Vincent
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles (ULB), Route de Lennik, 808, 1070, Brussels, Belgium
| | - Rafael Fernandez Fernandez
- Department of Intensive Care, Althaia Xarxa Assistencial Universitària de Manresa, Barcelona, Spain.,CIBERES, Madrid, Spain
| | - Silvia Cano Hernandez
- Department of Intensive Care, Althaia Xarxa Assistencial Universitària de Manresa, Barcelona, Spain
| | - Federica Zama Cavicchi
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles (ULB), Route de Lennik, 808, 1070, Brussels, Belgium
| | - Jacques Creteur
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles (ULB), Route de Lennik, 808, 1070, Brussels, Belgium
| | - Fabio Silvio Taccone
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles (ULB), Route de Lennik, 808, 1070, Brussels, Belgium.
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29
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Falvo MJ, Lindheimer JB, Serrador JM. Dynamic cerebral autoregulation is impaired in Veterans with Gulf War Illness: A case-control study. PLoS One 2018; 13:e0205393. [PMID: 30321200 PMCID: PMC6188758 DOI: 10.1371/journal.pone.0205393] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 09/25/2018] [Indexed: 02/03/2023] Open
Abstract
Neurological dysfunction has been reported in Gulf War Illness (GWI), including abnormal cerebral blood flow (CBF) responses to physostigmine challenge. However, it is unclear whether the CBF response to normal physiological challenges and regulation is similarly dysfunctional. The goal of the present study was to evaluate the CBF velocity response to orthostatic stress (i.e., sit-to-stand maneuver) and increased fractional concentration of carbon dioxide. 23 cases of GWI (GWI+) and 9 controls (GWI) volunteered for this study. Primary variables of interest included an index of dynamic autoregulation and cerebrovascular reactivity. Dynamic autoregulation was significantly lower in GWI+ than GWI- both for autoregulatory index (2.99±1.5 vs 4.50±1.5, p = 0.017). In addition, we observed greater decreases in CBF velocity both at the nadir after standing (-18.5±6.0 vs -9.8±4.9%, p = 0.001) and during steady state standing (-5.7±7.1 vs -1.8±3.2%, p = 0.042). In contrast, cerebrovascular reactivity was not different between groups. In our sample of Veterans with GWI, dynamic autoregulation was impaired and consistent with greater cerebral hypoperfusion when standing. This reduced CBF may contribute to cognitive difficulties in these Veterans when upright.
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Affiliation(s)
- Michael J. Falvo
- War Related Illness and Injury Study Center, Department of Veterans Affairs, East Orange, New Jersey, United States of America
- Department of Pharmacology, Physiology and Neuroscience, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, New Jersey, United States of America
- Department of Physical Medicine and Rehabilitation, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, New Jersey, United States of America
| | - Jacob B. Lindheimer
- William S. Middleton Memorial Veterans Hospital, Department of Veterans Affairs, Madison, Wisconsin, United States of America
- Department of Kinesiology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Jorge M. Serrador
- War Related Illness and Injury Study Center, Department of Veterans Affairs, East Orange, New Jersey, United States of America
- Department of Pharmacology, Physiology and Neuroscience, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, New Jersey, United States of America
- Department of Cardiovascular Electronics, National University of Ireland Galway, Galway, Connacht, IRE
- * E-mail:
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30
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Chung CC, Pimentel Maldonado DA, Jor'dan AJ, Alfaro FJ, Lioutas VA, Núñez MZ, Novak V. Lower cerebral vasoreactivity as a predictor of gait speed decline in type 2 diabetes mellitus. J Neurol 2018; 265:2267-2276. [PMID: 30062523 PMCID: PMC6162165 DOI: 10.1007/s00415-018-8981-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 07/17/2018] [Accepted: 07/19/2018] [Indexed: 01/27/2023]
Abstract
Gait speed is an indicator of overall functional health and is correlated with survival in older adults. We prospectively evaluated the long-term association between cerebral vasoreactivity and gait speed during normal walking (NW) and dual-task walking (DTW) in older adults with and without type 2 diabetes mellitus (T2DM). 40 participants (aged 67.3 ± 8.8 years, 20 with T2DM) completed a 2-year prospective study consisting of MRI, blood sampling, and gait assessments. The whole brain vasoreactivity was quantified using continuous arterial spin labeling MRI. Gait speed during DTW was assessed by subtracting serial sevens. Dual-task cost was calculated as the percent change in gait speed from NW to DTW. In the entire cohort, higher glycemic profiles were associated with a slower gait speed. In the diabetic group, lower vasoreactivity was associated with a slower gait speed during NW ([Formula: see text] = 0.30, p = 0.019) and DTW ([Formula: see text] = 0.35, p = 0.01) and a higher dual-task cost ([Formula: see text] = 0.69, p = 0.009) at 2-year follow-up. The participants with T2DM and lower cerebral vasoreactivity had a greater decrease in gait speed during NW and DTW after the 2-year follow-up ([Formula: see text] = 0.17, p = 0.04 and [Formula: see text] = 0.28, p = 0.03, respectively). Longer diabetes duration was associated with a higher dual-task cost ([Formula: see text] = 0.19, p = 0.04) and a greater decrease in gait speed during NW ([Formula: see text] = 0.17, p = 0.02). These findings indicate that in older adults with type 2 diabetes, gait performance is highly dependent on the integrity of cerebrovascular regulation.
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Affiliation(s)
- Chen-Chih Chung
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, 185 Pilgrim Road, Palmer 127, Boston, MA, 02215, USA
- Department of Neurology, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan, Republic of China
- Graduate Institute of Biomedical Informatics, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan, Republic of China
| | - Daniela A Pimentel Maldonado
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, 185 Pilgrim Road, Palmer 127, Boston, MA, 02215, USA
- Department of Gerontology, Beth Israel Deaconess Medical Center, Boston, MA, USA
- Department of Neurology, University of Massachusetts Medical School, Worcester, USA
| | - Azizah J Jor'dan
- Department of Gerontology, Beth Israel Deaconess Medical Center, Boston, MA, USA
- Institute for Aging Research, Hebrew SeniorLife, Harvard Medical School, Boston, USA
- New England Geriatric Research, Education and Clinical Center, VA Boston Healthcare System, Boston, MA, USA
| | - Freddy J Alfaro
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, 185 Pilgrim Road, Palmer 127, Boston, MA, 02215, USA
| | - Vasileios-Arsenios Lioutas
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, 185 Pilgrim Road, Palmer 127, Boston, MA, 02215, USA
| | - Maria Zunilda Núñez
- Biomedical and Clinical Research Center (CINBIOCLI), Santiago, Dominican Republic
| | - Vera Novak
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, 185 Pilgrim Road, Palmer 127, Boston, MA, 02215, USA.
- Department of Gerontology, Beth Israel Deaconess Medical Center, Boston, MA, USA.
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31
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Bazzigaluppi P, Lake EM, Beckett TL, Koletar MM, Weisspapir I, Heinen S, Mester J, Lai A, Janik R, Dorr A, McLaurin J, Stanisz GJ, Carlen PL, Stefanovic B. Imaging the Effects of β-Hydroxybutyrate on Peri-Infarct Neurovascular Function and Metabolism. Stroke 2018; 49:2173-2181. [DOI: 10.1161/strokeaha.118.020586] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Paolo Bazzigaluppi
- From the Physical Sciences Platform (P.B., E.M.L., T.L.B., M.M.K., I.W., J.M., R.J., A.D., G.J.S., B.S.)
- Sunnybrook Research Institute, Toronto, Canada; Fundamental Neurobiology, Krembil Research Institute, Toronto, Canada (P.B., I.W., P.L.C.)
| | - Evelyn M. Lake
- From the Physical Sciences Platform (P.B., E.M.L., T.L.B., M.M.K., I.W., J.M., R.J., A.D., G.J.S., B.S.)
| | - Tina L. Beckett
- From the Physical Sciences Platform (P.B., E.M.L., T.L.B., M.M.K., I.W., J.M., R.J., A.D., G.J.S., B.S.)
| | - Margaret M. Koletar
- From the Physical Sciences Platform (P.B., E.M.L., T.L.B., M.M.K., I.W., J.M., R.J., A.D., G.J.S., B.S.)
| | - Iliya Weisspapir
- From the Physical Sciences Platform (P.B., E.M.L., T.L.B., M.M.K., I.W., J.M., R.J., A.D., G.J.S., B.S.)
- Sunnybrook Research Institute, Toronto, Canada; Fundamental Neurobiology, Krembil Research Institute, Toronto, Canada (P.B., I.W., P.L.C.)
| | | | - James Mester
- From the Physical Sciences Platform (P.B., E.M.L., T.L.B., M.M.K., I.W., J.M., R.J., A.D., G.J.S., B.S.)
- Biological Sciences (J.M.)
| | - Aaron Lai
- Department of Laboratory Medicine and Pathobiology (A.L., J.M.)
| | - Rafal Janik
- From the Physical Sciences Platform (P.B., E.M.L., T.L.B., M.M.K., I.W., J.M., R.J., A.D., G.J.S., B.S.)
- Department of Medical Biophysics (J.M., R.J., G.J.S., B.S.), University of Toronto, Canada
| | - Adrienne Dorr
- From the Physical Sciences Platform (P.B., E.M.L., T.L.B., M.M.K., I.W., J.M., R.J., A.D., G.J.S., B.S.)
| | - JoAnne McLaurin
- Department of Laboratory Medicine and Pathobiology (A.L., J.M.)
- Department of Medical Biophysics (J.M., R.J., G.J.S., B.S.), University of Toronto, Canada
| | - Greg J. Stanisz
- From the Physical Sciences Platform (P.B., E.M.L., T.L.B., M.M.K., I.W., J.M., R.J., A.D., G.J.S., B.S.)
- Department of Medical Biophysics (J.M., R.J., G.J.S., B.S.), University of Toronto, Canada
| | - Peter L. Carlen
- Sunnybrook Research Institute, Toronto, Canada; Fundamental Neurobiology, Krembil Research Institute, Toronto, Canada (P.B., I.W., P.L.C.)
| | - Bojana Stefanovic
- From the Physical Sciences Platform (P.B., E.M.L., T.L.B., M.M.K., I.W., J.M., R.J., A.D., G.J.S., B.S.)
- Department of Medical Biophysics (J.M., R.J., G.J.S., B.S.), University of Toronto, Canada
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Olesen ND, Fischer M, Secher NH. Sodium nitroprusside dilates cerebral vessels and enhances internal carotid artery flow in young men. J Physiol 2018; 596:3967-3976. [PMID: 29917239 DOI: 10.1113/jp275887] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 06/12/2018] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS Sodium nitroprusside lowers blood pressure by vasodilatation but is reported to reduce cerebral blood flow. In healthy young men sodium nitroprusside reduced blood pressure, total peripheral resistance, and arterial CO2 tension and yet cerebral blood flow was maintained, with an increase in internal carotid artery blood flow and cerebrovascular conductance. Sodium nitroprusside induces both systemic and cerebral vasodilatation affecting internal carotid artery more than vertebral artery flow. ABSTRACT Cerebral autoregulation maintains cerebral blood flow (CBF) despite marked changes in mean arterial pressure (MAP). Sodium nitroprusside (SNP) reduces blood pressure by vasodilatation but is reported to lower CBF, probably by a reduction in its perfusion pressure. We evaluated the influence of SNP on CBF and aimed for a 20% and then 40% reduction in MAP, while keeping MAP ≥ 50 mmHg, to challenge cerebral autoregulation. In 19 healthy men (age 24 ± 4 years; mean ± SD) duplex ultrasound determined right internal carotid (ICA) and vertebral artery (VA) blood flow. The SNP reduced MAP (from 83 ± 8 to 69 ± 8 and 58 ± 4 mmHg; both P < 0.0001), total peripheral resistance, and arterial CO2 tension (P aC O2; 41 ± 3 vs. 39 ± 3 and 37 ± 4 mmHg; both P < 0.01). Yet ICA flow increased with the moderate reduction in MAP but returned to the baseline value with the large reduction in MAP (336 ± 66 vs. 365 ± 69; P = 0.013 and 349 ± 82 ml min-1 ; n.s.), while VA flow (114 ± 34 vs. 112 ± 38 and 110 ± 42 ml min-1 ; both n.s.) and CBF ((ICA + VA flow) × 2; 899 ± 135 vs. 962 ± 127 and 918 ± 197 ml min-1 ; both n.s.) were maintained with increased cerebrovascular conductance. In conclusion, CBF is maintained during SNP-induced reduction in MAP despite reduced P aC O2 and the results indicate that SNP dilates cerebral vessels and increases ICA flow.
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Affiliation(s)
- Niels D Olesen
- Department of Anaesthesia, The Copenhagen Muscle Research Centre, Rigshospitalet, Copenhagen, Denmark.,Department of Biomedical Sciences, University of Copenhagen, Denmark
| | - Mads Fischer
- Department of Anaesthesia, The Copenhagen Muscle Research Centre, Rigshospitalet, Copenhagen, Denmark.,Department of Nutrition, Exercise and Sports, University of Copenhagen, Denmark
| | - Niels H Secher
- Department of Anaesthesia, The Copenhagen Muscle Research Centre, Rigshospitalet, Copenhagen, Denmark
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Schulz JM, Al-Khazraji BK, Shoemaker JK. Sodium nitroglycerin induces middle cerebral artery vasodilatation in young, healthy adults. Exp Physiol 2018; 103:1047-1055. [PMID: 29766604 PMCID: PMC6099468 DOI: 10.1113/ep087022] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 05/08/2018] [Indexed: 01/03/2023]
Abstract
NEW FINDINGS What is the central question of this study? Nitric oxide causes dilatation in peripheral vessels; however, whether nitric oxide affects basal cerebral artery dilatation has not been explored. What is the main finding and its importance? This study demonstrated that vasodilatation occurs in the right middle cerebral artery in response to exogenous nitric oxide. However, blood velocity decreased and, therefore, overall cerebral blood flow remained unchanged. This study provides new insight into the role of nitric oxide in cerebral blood flow control. ABSTRACT Recent evidence indicates that basal cerebral conduit vessels dilate with hypercapnia, with a nitric oxide (NO) mechanism explaining one way in which parenchymal cerebral arterioles dilate. However, whether NO affects basal cerebral artery dilatation remains unknown. This study quantified the effect of an exogenous NO donor [sodium nitroglycerin (NTG); 0.4 mg sublingual spray] on the right middle cerebral artery (rMCA) cross-sectional area (CSA), blood velocity and overall blood flow. Measures of vessel CSA (7 T magnetic resonance imaging) and MCA blood velocity (transcranial Doppler ultrasound) were made at baseline (BL) and after exogenous NTG or placebo (PLO) administration in young, healthy individuals (n = 10, two males, age range 20-23 years). The CSA increased in the rMCA [BL, 5.2 ± 1.2 mm2 ; PLO, 5.4 ± 1.5 mm2 ; NTG, 6.6 ± 1.5 mm2 , P < 0.05; mean ± SD]. Concurrently, rMCA blood velocity decreased from BL during NTG compared with PLO (BL, 67 ± 10 cm s-1 ; PLO, 62 ± 10 cm s-1 ; NTG, 59 ± 9.3 cm s-1 , P < 0.05; mean ± SD]. However, total MCA blood flow did not change with NTG or PLO [BL, 221 ± 37.4 ml min-1 ; PLO, 218 ± 35.0 ml min-1 ; NTG, 213 ± 46.4 ml min-1 ). Therefore, exogenous NO mediates a dilatory response in the rMCA, but not in its downstream vascular bed.
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Affiliation(s)
- Jenna M Schulz
- School of Physical Therapy, Department of Health Sciences, Western University, London, ON, Canada
| | - Baraa K Al-Khazraji
- School of Kinesiology, Department of Health Sciences, Western University, London, ON, Canada
| | - J Kevin Shoemaker
- Department of Physiology and Pharmacology, Western University, London, ON, Canada.,School of Kinesiology, Department of Health Sciences, Western University, London, ON, Canada
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Hurr C, Patik JC, Kim K, Brothers RM. Blunted cerebral vascular responsiveness to hypercapnia in obese individuals. Exp Physiol 2017; 102:1300-1308. [DOI: 10.1113/ep086446] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Accepted: 07/18/2017] [Indexed: 11/08/2022]
Affiliation(s)
- Chansol Hurr
- Department of Kinesiology and Health Education; University of Texas at Austin; Austin TX USA
- Department of Pharmacology and Physiology; George Washington University; DC USA
| | - Jordan C. Patik
- Department of Kinesiology and Health Education; University of Texas at Austin; Austin TX USA
- Department of Kinesiology; University of Texas at Arlington; Arlington TX USA
| | - KiYoung Kim
- Department of Kinesiology and Health Education; University of Texas at Austin; Austin TX USA
- Department of Pathology; University of Alabama at Birmingham; Birmingham AL USA
| | - R. Matthew Brothers
- Department of Kinesiology and Health Education; University of Texas at Austin; Austin TX USA
- Department of Kinesiology; University of Texas at Arlington; Arlington TX USA
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Stewart JM, Suggs M, Merchant S, Sutton R, Terilli C, Visintainer P, Medow MS. Postsynaptic α1-Adrenergic Vasoconstriction Is Impaired in Young Patients With Vasovagal Syncope and Is Corrected by Nitric Oxide Synthase Inhibition. Circ Arrhythm Electrophysiol 2017; 9:CIRCEP.115.003828. [PMID: 27444639 DOI: 10.1161/circep.115.003828] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Accepted: 06/15/2016] [Indexed: 11/16/2022]
Abstract
BACKGROUND Syncope is a sudden transient loss of consciousness and postural tone with spontaneous recovery; the most common form is vasovagal syncope (VVS). During VVS, gravitational pooling excessively reduces central blood volume and cardiac output. In VVS, as in hemorrhage, impaired adrenergic vasoconstriction and venoconstriction result in hypotension. We hypothesized that impaired adrenergic responsiveness because of excess nitric oxide can be reversed by reducing nitric oxide. METHODS AND RESULTS We recorded cardiopulmonary dynamics in supine syncope patients and healthy volunteers (aged 15-27 years) challenged with a dose-response using the α1-agonist phenylephrine (PE), with and without the nitric oxide synthase inhibitor N(G)-monomethyl-L-arginine, monoacetate salt (L-NMMA). Systolic and diastolic pressures among control and VVS were the same, although they increased after L-NMMA and saline+PE (volume and pressor control for L-NMMA). Heart rate was significantly reduced by L-NMMA (P<0.05) for control and VVS compared with baseline, but there was no significant difference in heart rate between L-NMMA and saline+PE. Cardiac output and splanchnic blood flow were reduced by L-NMMA for control and VVS (P<0.05) compared with baseline, while total peripheral resistance increased (P<0.05). PE dose-response for splanchnic flow and resistance were blunted for VVS compared with control after saline+PE, but enhanced after L-NMMA (P<0.001). Postsynaptic α1-adrenergic vasoconstrictive impairment was greatest in the splanchnic vasculature, and splanchnic blood flow was unaffected by PE. Forearm and calf α1-adrenergic vasoconstriction were unimpaired in VVS and unaffected by L-NMMA. CONCLUSIONS Impaired postsynaptic α1-adrenergic vasoconstriction in young adults with VVS can be corrected by nitric oxide synthase inhibition, demonstrated with our use of L-NMMA.
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Affiliation(s)
- Julian M Stewart
- From the Departments of Pediatrics (J.M.S., S.M., C.T., M.S.M.), Physiology (J.M.S., M.S., M.S.M.), New York Medical College, Valhalla, NY; The National Heart & Lung Institute, Imperial College, London, United Kingdom (R.S.); and Department of Medicine, Baystate Medical Center, Springfield & Tufts University School of Medicine, MA (P.V.).
| | - Melissa Suggs
- From the Departments of Pediatrics (J.M.S., S.M., C.T., M.S.M.), Physiology (J.M.S., M.S., M.S.M.), New York Medical College, Valhalla, NY; The National Heart & Lung Institute, Imperial College, London, United Kingdom (R.S.); and Department of Medicine, Baystate Medical Center, Springfield & Tufts University School of Medicine, MA (P.V.)
| | - Sana Merchant
- From the Departments of Pediatrics (J.M.S., S.M., C.T., M.S.M.), Physiology (J.M.S., M.S., M.S.M.), New York Medical College, Valhalla, NY; The National Heart & Lung Institute, Imperial College, London, United Kingdom (R.S.); and Department of Medicine, Baystate Medical Center, Springfield & Tufts University School of Medicine, MA (P.V.)
| | - Richard Sutton
- From the Departments of Pediatrics (J.M.S., S.M., C.T., M.S.M.), Physiology (J.M.S., M.S., M.S.M.), New York Medical College, Valhalla, NY; The National Heart & Lung Institute, Imperial College, London, United Kingdom (R.S.); and Department of Medicine, Baystate Medical Center, Springfield & Tufts University School of Medicine, MA (P.V.)
| | - Courtney Terilli
- From the Departments of Pediatrics (J.M.S., S.M., C.T., M.S.M.), Physiology (J.M.S., M.S., M.S.M.), New York Medical College, Valhalla, NY; The National Heart & Lung Institute, Imperial College, London, United Kingdom (R.S.); and Department of Medicine, Baystate Medical Center, Springfield & Tufts University School of Medicine, MA (P.V.)
| | - Paul Visintainer
- From the Departments of Pediatrics (J.M.S., S.M., C.T., M.S.M.), Physiology (J.M.S., M.S., M.S.M.), New York Medical College, Valhalla, NY; The National Heart & Lung Institute, Imperial College, London, United Kingdom (R.S.); and Department of Medicine, Baystate Medical Center, Springfield & Tufts University School of Medicine, MA (P.V.)
| | - Marvin S Medow
- From the Departments of Pediatrics (J.M.S., S.M., C.T., M.S.M.), Physiology (J.M.S., M.S., M.S.M.), New York Medical College, Valhalla, NY; The National Heart & Lung Institute, Imperial College, London, United Kingdom (R.S.); and Department of Medicine, Baystate Medical Center, Springfield & Tufts University School of Medicine, MA (P.V.).
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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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37
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Stewart JM, Sutton R, Kothari ML, Goetz AM, Visintainer P, Medow MS. Nitric oxide synthase inhibition restores orthostatic tolerance in young vasovagal syncope patients. Heart 2017; 103:1711-1718. [PMID: 28501796 DOI: 10.1136/heartjnl-2017-311161] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Revised: 03/21/2017] [Accepted: 03/21/2017] [Indexed: 12/12/2022] Open
Abstract
OBJECTIVE Syncope is sudden transient loss of consciousness and postural tone with spontaneous recovery; the most common form is vasovagal syncope (VVS). We previously demonstrated impaired post-synaptic adrenergic responsiveness in young VVS patients was reversed by blocking nitric oxide synthase (NOS). We hypothesised that nitric oxide may account for reduced orthostatic tolerance in young recurrent VVS patients. METHODS We recorded haemodynamics in supine VVS and healthy volunteers (aged 15-27 years), challenged with graded lower body negative pressure (LBNP) (-15, -30, -45 mm Hg each for 5 min, then -60 mm Hg for a maximum of 50 min) with and without NOS inhibitor NG-monomethyl-L-arginine acetate (L-NMMA). Saline plus phenylephrine (Saline+PE) was used as volume and pressor control for L-NMMA. RESULTS Controls endured 25.9±4.0 min of LBNP during Saline+PE compared with 11.6±1.4 min for fainters (p<0.001). After L-NMMA, control subjects endured 24.8±3.2 min compared with 22.6±1.6 min for fainters. Mean arterial pressure decreased more in VVS patients during LBNP with Saline+PE (p<0.001) which was reversed by L-NMMA; cardiac output decreased similarly in controls and VVS patients and was unaffected by L-NMMA. Total peripheral resistance increased for controls but decreased for VVS during Saline+PE (p<0.001) but was similar following L-NMMA. Splanchnic vascular resistance increased during LBNP in controls, but decreased in VVS patients following Saline+PE which L-NMMA restored. CONCLUSIONS We conclude that arterial vasoconstriction is impaired in young VVS patients, which is corrected by NOS inhibition. The data suggest that both pre- and post-synaptic arterial vasoconstriction may be affected by nitric oxide.
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Affiliation(s)
- Julian M Stewart
- Departments of Pediatrics, New York Medical College, Valhalla, New York, USA.,Departments of Physiology, New York Medical College, Valhalla, New York, USA
| | - Richard Sutton
- The National Heart & Lung Institute, Imperial College, London, UK
| | - Mira L Kothari
- Departments of Pediatrics, New York Medical College, Valhalla, New York, USA
| | - Amanda M Goetz
- Departments of Pediatrics, New York Medical College, Valhalla, New York, USA
| | - Paul Visintainer
- Baystate Medical Center, University of Massachusetts School of Medicine 4, Springfield MA, USA
| | - Marvin Scott Medow
- Departments of Pediatrics, New York Medical College, Valhalla, New York, USA.,Departments of Physiology, New York Medical College, Valhalla, New York, USA
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Bath PMW, Krishnan K, Appleton JP. Nitric oxide donors (nitrates), L-arginine, or nitric oxide synthase inhibitors for acute stroke. Cochrane Database Syst Rev 2017; 4:CD000398. [PMID: 28429459 PMCID: PMC6478181 DOI: 10.1002/14651858.cd000398.pub2] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
BACKGROUND Nitric oxide (NO) has multiple effects that may be beneficial in acute stroke, including lowering blood pressure, and promoting reperfusion and cytoprotection. Some forms of nitric oxide synthase inhibition (NOS-I) may also be beneficial. However, high concentrations of NO are likely to be toxic to brain tissue. This is an update of a Cochrane review first published in 1998, and last updated in 2002. OBJECTIVES To assess the safety and efficacy of NO donors, L-arginine, and NOS-I in people with acute stroke. SEARCH METHODS We searched the Cochrane Stroke Group Trials Register (last searched 6 February 2017), MEDLINE (1966 to June 2016), Embase (1980 to June 2016), ISI Science Citation Indexes (1981 to June 2016), Stroke Trials Registry (searched June 2016), International Standard Randomised Controlled Trial Number (ISRCTN) (searched June 2016), Clinical Trials registry (searched June 2016), and International Clinical Trials Registry Platform (ICTRP) (searched June 2016). Previously, we had contacted drug companies and researchers in the field. SELECTION CRITERIA Randomised controlled trials comparing nitric oxide donors, L-arginine, or NOS-I versus placebo or open control in people within one week of onset of confirmed stroke. DATA COLLECTION AND ANALYSIS Two review authors independently applied the inclusion criteria, assessed trial quality and risk of bias, and extracted data. The review authors cross-checked data and resolved issues through discussion. We obtained published and unpublished data, as available. Data were reported as mean difference (MD) or odds ratio (OR) with 95% confidence intervals (CI). MAIN RESULTS We included five completed trials, involving 4197 participants; all tested transdermal glyceryl trinitrate (GTN), an NO donor. The assessed risk of bias was low across the included studies; one study was double-blind, one open-label and three were single-blind. All included studies had blinded outcome assessment. Overall, GTN did not improve the primary outcome of death or dependency at the end of trial (modified Rankin Scale (mRS) > 2, OR 0.97, 95% CI 0.86 to 1.10, 4195 participants, high-quality evidence). GTN did not improve secondary outcomes, including death (OR 0.78, 95% CI 0.40 to 1.50) and quality of life (MD -0.01, 95% CI -0.17 to 0.15) at the end of trial overall (high-quality evidence). Systolic/diastolic blood pressure (BP) was lower in people treated with GTN (MD -7.2 mmHg (95% CI -8.6 to -5.9) and MD -3.3 (95% CI -4.2 to -2.5) respectively) and heart rate was higher (MD 2.0 beats per minute (95% CI 1.1 to 2.9)). Headache was more common in those randomised to GTN (OR 2.37, 95% CI 1.55 to 3.62). We did not find any trials assessing other nitrates, L-arginine, or NOS-I. AUTHORS' CONCLUSIONS There is currently insufficient evidence to recommend the use of NO donors, L-arginine or NOS-I in acute stroke, and only one drug (GTN) has been assessed. In people with acute stroke, GTN reduces blood pressure, increases heart rate and headache, but does not alter clinical outcome (all based on high-quality evidence).
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Affiliation(s)
- Philip MW Bath
- University of NottinghamStroke, Division of Clinical NeuroscienceCity Hospital CampusNottinghamUKNG5 1PB
| | - Kailash Krishnan
- University of NottinghamStroke, Division of Clinical NeuroscienceCity Hospital CampusNottinghamUKNG5 1PB
| | - Jason P Appleton
- University of NottinghamStroke, Division of Clinical NeuroscienceCity Hospital CampusNottinghamUKNG5 1PB
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The Effect of Chunghyul-Dan on Hyperventilation-Induced Carbon Dioxide Reactivity of the Middle Cerebral Artery in Normal Subjects: A Dose-Dependent Study. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2017; 2017:4567217. [PMID: 28512500 PMCID: PMC5415863 DOI: 10.1155/2017/4567217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 03/06/2017] [Accepted: 03/09/2017] [Indexed: 11/21/2022]
Abstract
Background. This study was conducted to show the prompt effect of chunghyul-dan (CHD) on cerebral hemodynamics in order to provide evidence for its use in stroke prevention. Methods. Hyperventilation-induced CO2 reactivity of the middle cerebral artery was measured in 12 healthy male volunteers (mean age: 26.3 ± 1.1 years) using transcranial Doppler sonography. All subjects were examined before and for 3 hours after administration, with an interval of 1 week between measurements. Results. Compared to baseline, the CO2 reactivity of the middle cerebral artery increased significantly at 2 and 3 hours after the administration of CHD (600 mg and 1200 mg). The mean blood pressure and heart rate did not vary from the baseline values in all groups. Conclusion. These data suggest that CHD administration (especially 600 mg) immediately improves cerebral blood flow.
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40
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Abstract
The nitric oxide donor, glyceryl trinitrate (GTN), is a candidate treatment for the management of acute stroke with haemodynamic and potential reperfusion and neuroprotective effects. When administered as a transdermal patch during the acute and subacute phases after stroke, GTN was safe, lowered blood pressure, maintained cerebral blood flow, and did not induce cerebral steal or alter functional outcome. However, when given within 6 h of stroke onset, GTN reduced death and dependency (odds ratio 0.52; 95% confidence interval 0.34-0.78), death, disability, cognitive impairment and mood disturbance, and improved quality of life (data from two trials, n = 312). In a pooled analysis of four studies (n = 186), GTN reduced between-visit systolic blood pressure variability over days 1-7 compared with no GTN (mean difference -2.09; 95% confidence interval -3.83 to -0.35; p = 0.019). The efficacy of GTN given in the ultra-acute/pre-hospital setting is currently being assessed and, if found to be beneficial, the implications for hyperacute stroke practice are significant. Here, we discuss the evidence to date, potential mechanisms of action and future possibilities, including unanswered questions, for the therapeutic potential of GTN in acute stroke.
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Kerner NA, Roose SP. Obstructive Sleep Apnea is Linked to Depression and Cognitive Impairment: Evidence and Potential Mechanisms. Am J Geriatr Psychiatry 2016; 24:496-508. [PMID: 27139243 PMCID: PMC5381386 DOI: 10.1016/j.jagp.2016.01.134] [Citation(s) in RCA: 160] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Revised: 11/17/2015] [Accepted: 01/12/2016] [Indexed: 12/19/2022]
Abstract
Obstructive sleep apnea (OSA) is highly prevalent but very frequently undiagnosed. OSA is an independent risk factor for depression and cognitive impairment/dementia. Herein the authors review studies in the literature pertinent to the effects of OSA on the cerebral microvascular and neurovascular systems and present a model to describe the key pathophysiologic mechanisms that may underlie the associations, including hypoperfusion, endothelial dysfunction, and neuroinflammation. Intermittent hypoxia plays a critical role in initiating and amplifying these pathologic processes. Hypoperfusion and impaired cerebral vasomotor reactivity lead to the development or progression of cerebral small vessel disease (C-SVD). Hypoxemia exacerbates these processes, resulting in white matter lesions, white matter integrity abnormalities, and gray matter loss. Blood-brain barrier (BBB) hyperpermeability and neuroinflammation lead to altered synaptic plasticity, neuronal damage, and worsening C-SVD. Thus, OSA may initiate or amplify the pathologic processes of C-SVD and BBB dysfunction, resulting in the development or exacerbation of depressive symptoms and cognitive deficits. Given the evidence that adequate treatment of OSA with continuous positive airway pressure improves depression and neurocognitive functions, it is important to identify OSA when assessing patients with depression or cognitive impairment. Whether treatment of OSA changes the deteriorating trajectory of elderly patients with already-diagnosed vascular depression and cognitive impairment/dementia remains to be determined in randomized controlled trials.
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Jeong SM, Kim SO, DeLorey DS, Babb TG, Levine BD, Zhang R. Lack of correlation between cerebral vasomotor reactivity and dynamic cerebral autoregulation during stepwise increases in inspired CO2 concentration. J Appl Physiol (1985) 2016; 120:1434-41. [PMID: 27103653 DOI: 10.1152/japplphysiol.00390.2015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 04/18/2016] [Indexed: 11/22/2022] Open
Abstract
Cerebral vasomotor reactivity (CVMR) and dynamic cerebral autoregulation (CA) are measured extensively in clinical and research studies. However, the relationship between these measurements of cerebrovascular function is not well understood. In this study, we measured changes in cerebral blood flow velocity (CBFV) and arterial blood pressure (BP) in response to stepwise increases in inspired CO2 concentrations of 3 and 6% to assess CVMR and dynamic CA in 13 healthy young adults [2 women, 32 ± 9 (SD) yr]. CVMR was assessed as percentage changes in CBFV (CVMRCBFV) or cerebrovascular conductance index (CVCi, CVMRCVCi) in response to hypercapnia. Dynamic CA was estimated by performing transfer function analysis between spontaneous oscillations in BP and CBFV. Steady-state CBFV and CVCi both increased exponentially during hypercapnia; CVMRCBFV and CVMRCVCi were greater at 6% (3.85 ± 0.90 and 2.45 ± 0.79%/mmHg) than at 3% CO2 (2.09 ± 1.47 and 0.21 ± 1.56%/mmHg, P = 0.009 and 0.005, respectively). Furthermore, CVMRCBFV was greater than CVMRCVCi during either 3 or 6% CO2 (P = 0.017 and P < 0.001, respectively). Transfer function gain and coherence increased in the very low frequency range (0.02-0.07 Hz), and phase decreased in the low-frequency range (0.07-0.20 Hz) when breathing 6%, but not 3% CO2 There were no correlations between the measurements of CVMR and dynamic CA. These findings demonstrated influences of inspired CO2 concentrations on assessment of CVMR and dynamic CA. The lack of correlation between CVMR and dynamic CA suggests that cerebrovascular responses to changes in arterial CO2 and BP are mediated by distinct regulatory mechanisms.
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Affiliation(s)
- Sung-Moon Jeong
- Institute for Exercise and Environmental Medicine, Presbyterian Hospital of Dallas and University of Texas Southwestern Medical Center, Dallas, Texas; Department of Anesthesiology and Pain Medicine, College of Medicine, University of Ulsan, Asan Medical Center, Seoul, Korea
| | - Seon-Ok Kim
- Department of Clinical Epidemiology and Biostatistics, College of Medicine, University of Ulsan, Asan Medical Center, Seoul, Korea; and
| | - Darren S DeLorey
- Faculty of Physical Education and Recreation, University of Alberta, Edmonton, Alberta, Canada
| | - Tony G Babb
- Institute for Exercise and Environmental Medicine, Presbyterian Hospital of Dallas and University of Texas Southwestern Medical Center, Dallas, Texas
| | - Benjamin D Levine
- Institute for Exercise and Environmental Medicine, Presbyterian Hospital of Dallas and University of Texas Southwestern Medical Center, Dallas, Texas
| | - Rong Zhang
- Institute for Exercise and Environmental Medicine, Presbyterian Hospital of Dallas and University of Texas Southwestern Medical Center, Dallas, Texas;
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Kaur SS, Gonzales MM, Eagan DE, Goudarzi K, Tanaka H, Haley AP. Inflammation as a mediator of the relationship between cortical thickness and metabolic syndrome. Brain Imaging Behav 2015; 9:737-43. [PMID: 25376331 PMCID: PMC4424190 DOI: 10.1007/s11682-014-9330-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Metabolic Syndrome (MetS), the clustering of obesity, high blood pressure, and disordered glucose and lipid/lipoprotein metabolism within a single individual, is associated with poorer cognitive function. It has been hypothesized that cognitive impairment in MetS occurs primarily within the context of inflammation. MetS risk factors are also associated with thinning of the cerebral cortex. However, the mechanisms by which MetS and inflammation affect the brain are poorly understood. The present study used statistical mediation to examine the relationship between MetS risk factors, cortical thickness in a priori regions of interest (ROIs) and inflammation. ROIs were chosen from the previous literature. Forty-three adults between the ages of 40 and 60 years underwent a health screen, neuropsychological testing and structural magnetic resonance imaging. Serum levels of pro-inflammatory markers (interleukin 1, interleukin 2, interleukin 6 and C-Reactive Protein) were measured using enzyme-linked immunosorbent assays. A higher number of MetS risk factors were associated with thinning in the inferior frontal ROI (β = -0.35, p = 0.019) as well as higher levels of serum interleukin 2 (β = 0.31, p = 0.04). A higher level of serum interleukin 2 was also associated with reduced thickness in the inferior frontal gyrus (β = -0.41, p = 0.013). After accounting for the effects of interleukin 2, the number of MetS risk factors was no longer associated with cortical thickness in the inferior frontal gyrus indicating successful statistical mediation. The results indicate a potentially important role for inflammation in linking MetS to cortical thinning and cognitive vulnerability.
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Affiliation(s)
- Sonya S Kaur
- Department of Psychology, The University of Texas at Austin, 108 E. Dean Keeton, Stop A8000, Austin, TX, 78712, USA
- Imaging Research Center, The University of Texas at Austin, Austin, TX, USA
| | - Mitzi M Gonzales
- Department of Psychology, The University of Texas at Austin, 108 E. Dean Keeton, Stop A8000, Austin, TX, 78712, USA
- Imaging Research Center, The University of Texas at Austin, Austin, TX, USA
| | - Danielle E Eagan
- Department of Psychology, The University of Texas at Austin, 108 E. Dean Keeton, Stop A8000, Austin, TX, 78712, USA
- Imaging Research Center, The University of Texas at Austin, Austin, TX, USA
| | - Katyoon Goudarzi
- Department of Psychology, The University of Texas at Austin, 108 E. Dean Keeton, Stop A8000, Austin, TX, 78712, USA
| | - Hirofumi Tanaka
- Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, TX, USA
- Imaging Research Center, The University of Texas at Austin, Austin, TX, USA
| | - Andreana P Haley
- Department of Psychology, The University of Texas at Austin, 108 E. Dean Keeton, Stop A8000, Austin, TX, 78712, USA.
- Imaging Research Center, The University of Texas at Austin, Austin, TX, USA.
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Rimpilä V, Hosokawa K, Huhtala H, Saaresranta T, Salminen AV, Polo O. Transcutaneous carbon dioxide during sleep-disordered breathing. Respir Physiol Neurobiol 2015; 219:95-102. [PMID: 26474829 DOI: 10.1016/j.resp.2015.10.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 09/15/2015] [Accepted: 10/06/2015] [Indexed: 11/30/2022]
Abstract
Respiratory drive is tightly controlled by the carbon dioxide levels. We tested the hypothesis that sequences of sleep apnoea (obstructive, central or mixed), hypopnoea and flow limitation are characterized by different levels of transcutaneous CO2 (PtcCO2). Polygraphic recordings (n=555) from patients with suspected sleep-disordered breathing (SDB) were retrospectively screened to find sequences (5 min or 10 events) of both SDB and steady breathing. Eighty-eight SDB sequences from 44 patients were included and PtcCO2 and SpO2 values were collected. PtcCO2 values during sequences were normalized by setting wakefulness level as 100%. In terms of PtcCO2, apnoea sequences with central component (central (n=7) and mixed (n=3) apnoea) did not differ from wakefulness (102.0% vs 100%, p=0.122) whereas obstructive apnoea (105.8%, p<0.001) and hypopnoea did (105.4%, p<0.001). PtcCO2 during flow limitation was higher than that during any other sequence, including steady breathing (112.2% vs 108.4%, p=0.022). Continuous PtcCO2 monitoring during sleep adds to the understanding of different SDB phenotypes.
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Affiliation(s)
- Ville Rimpilä
- School of Medicine, University of Tampere, Finland; Unesta Research Center, Tampere, Finland.
| | | | - Heini Huhtala
- School of Health Sciences, University of Tampere, Finland
| | - Tarja Saaresranta
- Division of Medicine, Department of Pulmonary Diseases, Turku University Hospital, and Department of Pulmonary Diseases and Clinical Allergology and Sleep Research Centre, Department of Physiology, University of Turku, Finland
| | - Aaro V Salminen
- School of Medicine, University of Tampere, Finland; Unesta Research Center, Tampere, Finland
| | - Olli Polo
- Unesta Research Center, Tampere, Finland; Department of Respiratory Medicine, University of Tampere and Tampere University Hospital, Tampere, Finland
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Sofronova SI, Tarasova OS, Gaynullina D, Borzykh AA, Behnke BJ, Stabley JN, McCullough DJ, Maraj JJ, Hanna M, Muller-Delp JM, Vinogradova OL, Delp MD. Spaceflight on the Bion-M1 biosatellite alters cerebral artery vasomotor and mechanical properties in mice. J Appl Physiol (1985) 2015; 118:830-8. [PMID: 25593287 PMCID: PMC4385880 DOI: 10.1152/japplphysiol.00976.2014] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Accepted: 01/13/2015] [Indexed: 01/03/2023] Open
Abstract
Conditions during spaceflight, such as the loss of the head-to-foot gravity vector, are thought to potentially alter cerebral blood flow and vascular resistance. The purpose of the present study was to determine the effects of long-term spaceflight on the functional, mechanical, and structural properties of cerebral arteries. Male C57BL/6N mice were flown 30 days in a Bion-M1 biosatellite. Basilar arteries isolated from spaceflight (SF) (n = 6), habitat control (HC) (n = 6), and vivarium control (VC) (n = 16) mice were used for in vitro functional and mechanical testing and histological structural analysis. The results demonstrate that vasoconstriction elicited through a voltage-gated Ca(2+) mechanism (30-80 mM KCl) and thromboxane A2 receptors (10(-8) - 3 × 10(-5) M U46619) are lower in cerebral arteries from SF mice. Inhibition of Rho-kinase activity (1 μM Y27632) abolished group differences in U46619-evoked contractions. Endothelium-dependent vasodilation elicited by acetylcholine (10 μM, 2 μM U46619 preconstriction) was virtually absent in cerebral arteries from SF mice. The pressure-diameter relation was lower in arteries from SF mice relative to that in HC mice, which was not related to differences in the extracellular matrix protein elastin or collagen content or the elastin/collagen ratio in the basilar arteries. Diameter, medial wall thickness, and medial cross-sectional area of unpressurized basilar arteries were not different among groups. These results suggest that the microgravity-induced attenuation of both vasoconstrictor and vasodilator properties may limit the range of vascular control of cerebral perfusion or impair the distribution of brain blood flow during periods of stress.
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Affiliation(s)
- Svetlana I Sofronova
- Institute for Biomedical Problems, Russian Academy of Sciences, Moscow; Faculty of Biology, M.V. Lomonosov Moscow State University
| | - Olga S Tarasova
- Institute for Biomedical Problems, Russian Academy of Sciences, Moscow; Faculty of Biology, M.V. Lomonosov Moscow State University
| | - Dina Gaynullina
- Institute for Biomedical Problems, Russian Academy of Sciences, Moscow; Faculty of Biology, M.V. Lomonosov Moscow State University; Department of Physiology, Russian National Research Medical University, Moscow, Russia
| | - Anna A Borzykh
- Institute for Biomedical Problems, Russian Academy of Sciences, Moscow
| | - Bradley J Behnke
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida
| | - John N Stabley
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida
| | - Danielle J McCullough
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida
| | - Joshua J Maraj
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida
| | - Mina Hanna
- Department of Materials Science and Engineering, Stanford University, Stanford, California
| | - Judy M Muller-Delp
- Department of Biomedical Sciences, Florida State University, Tallahassee, Florida; and
| | | | - Michael D Delp
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida; Department of Nutrition, Food and Exercise Sciences, Florida State University, Tallahassee, Florida
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Rusinek H, Ha J, Yau PL, Storey P, Tirsi A, Tsui WH, Frosch O, Azova S, Convit A. Cerebral perfusion in insulin resistance and type 2 diabetes. J Cereb Blood Flow Metab 2015; 35:95-102. [PMID: 25315860 PMCID: PMC4294398 DOI: 10.1038/jcbfm.2014.173] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Revised: 08/19/2014] [Accepted: 09/10/2014] [Indexed: 11/09/2022]
Abstract
Cerebral perfusion was evaluated in 87 subjects prospectively enrolled in three study groups-healthy controls (HC), patients with insulin resistance (IR) but not with diabetes, and type 2 diabetes mellitus (T2DM). Participants received a comprehensive 8-hour clinical evaluation and arterial spin labeling magnetic resonance imaging (MRI). In order of decreasing significance, an association was found between cerebral blood flow (CBF) and sex, waist circumference, diastolic blood pressure (BP), end tidal CO2, and verbal fluency score (R(2)=0.27, F=5.89, P<0.001). Mean gray-matter CBF in IR was 4.4 mL/100 g per minute lower than in control subjects (P=0.005), with no hypoperfusion in T2DM (P=0.312). Subjects with IR also showed no CO2 relationship (slope=-0.012) in the normocapnic range, in contrast to a strong relationship in healthy brains (slope=0.800) and intermediate response (slope=0.445) in diabetic patients. Since the majority of T2DM but few IR subjects were aggressively treated with blood glucose, cholesterol, and BP lowering medications, our finding could be attributed to the beneficial effect of these drugs.
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Affiliation(s)
- Henry Rusinek
- Department of Radiology, NYU School of Medicine, New York, New York, USA
| | - Jenny Ha
- Department of Psychiatry, NYU School of Medicine, New York, New York, USA
| | - Po Lai Yau
- Department of Psychiatry, NYU School of Medicine, New York, New York, USA
| | - Pippa Storey
- Department of Radiology, NYU School of Medicine, New York, New York, USA
| | - Aziz Tirsi
- Department of Psychiatry, NYU School of Medicine, New York, New York, USA
| | - Wai Hon Tsui
- Department of Psychiatry, NYU School of Medicine, New York, New York, USA
| | | | | | - Antonio Convit
- 1] Department of Psychiatry, NYU School of Medicine, New York, New York, USA [2] Nathan Kline Institute for Psychiatric Research, Orangeburg, New York, USA
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Hurr C, Kim K, Harrison ML, Brothers RM. Attenuated cerebral vasodilatory capacity in response to hypercapnia in college-aged African Americans. Exp Physiol 2014; 100:35-43. [PMID: 25557729 PMCID: PMC4489322 DOI: 10.1113/expphysiol.2014.082362] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 10/10/2014] [Indexed: 01/07/2023]
Abstract
African Americans (AAs) have increased risk for cardiovascular, cerebral vascular and metabolic disease, including hypertension, stroke, coronary artery disease, metabolic syndrome and type II diabetes, relative to Caucasian Americans (CAs). While it is accepted that endothelial function is impaired in AAs, less is known regarding their cerebral vasodilatory capacity in response to hypercapnia. We hypothesized that AAs have a reduction in the total range of change in cerebral blood flow velocity (CBFV) measured in the middle cerebral artery and an index of cerebral vascular conductance (CVCI) in response to changes in the partial pressure of end-tidal carbon dioxide () during rebreathing-induced hypercapnia when compared with CAs. Twenty-one healthy, college-aged AA (10 male) and 21 age- and sex-matched CA (10 male) subjects participated in this study. A four-parameter logistic regression was used for curve fitting the responses of CBFV and CVCI relative to changes in . The total ranges of change in CBFV (101 ± 18 versus 69 ± 23%; P < 0.001) and CVCI (83 ± 21 versus 58 ± 21%; P < 0.001) as well as the maximal increase in CBFV (205 ± 24 versus 169 ± 24%; P < 0.001) and CVCI (188 ± 30 versus 154 ± 19%; P < 0.001) were reduced during hypercapnia in AAs relative to CAs despite a similar increase in (change, 15 ± 3 versus 15 ± 3 mmHg; P = 0.65). In conclusion, these data indicate that AAs have attenuated cerebral vascular capacity to respond to hypercapnia when compared with CAs.
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Affiliation(s)
- Chansol Hurr
- Environmental and Autonomic Physiology Laboratory, Department of Kinesiology and Health Education, The University of Texas at Austin, TX, USA
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Static autoregulation in humans: a review and reanalysis. Med Eng Phys 2014; 36:1487-95. [DOI: 10.1016/j.medengphy.2014.08.001] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 06/07/2014] [Accepted: 08/03/2014] [Indexed: 01/12/2023]
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Hamner JW, Tan CO. Relative contributions of sympathetic, cholinergic, and myogenic mechanisms to cerebral autoregulation. Stroke 2014; 45:1771-7. [PMID: 24723314 PMCID: PMC4102642 DOI: 10.1161/strokeaha.114.005293] [Citation(s) in RCA: 101] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Prior work aimed at improving our understanding of human cerebral autoregulation has explored individual physiological mechanisms of autoregulation in isolation, but none has attempted to consolidate the individual roles of these mechanisms into a comprehensive model of the overall cerebral pressure-flow relationship. METHODS We retrospectively analyzed this relationship before and after pharmacological blockade of α-adrenergic-, muscarinic-, and calcium channel-mediated mechanisms in 43 healthy volunteers to determine the relative contributions of the sympathetic, cholinergic, and myogenic controllers to cerebral autoregulation. Projection pursuit regression was used to assess the effect of pharmacological blockade on the cerebral pressure-flow relationship. Subsequently, ANCOVA decomposition was used to determine the cumulative effect of these 3 mechanisms on cerebral autoregulation and whether they can fully explain it. RESULTS Sympathetic, cholinergic, and myogenic mechanisms together accounted for 62% of the cerebral pressure-flow relationship (P<0.05), with significant and distinct contributions from each of the 3 effectors. ANCOVA decomposition demonstrated that myogenic effectors were the largest determinant of the cerebral pressure-flow relationship, but their effect was outside of the autoregulatory region where neurogenic control appeared prepotent. CONCLUSIONS Our results suggest that myogenic effects occur outside the active region of autoregulation, whereas neurogenic influences are largely responsible for cerebral blood flow control within it. However, our model of cerebral autoregulation left 38% of the cerebral pressure-flow relationship unexplained, suggesting that there are other physiological mechanisms that contribute to cerebral autoregulation.
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Affiliation(s)
- J W Hamner
- From the Cardiovascular Research Laboratory, Spaulding Rehabilitation Hospital, Boston, MA (J.W.H., C.O.T.); and Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, MA (C.O.T.)
| | - Can Ozan Tan
- From the Cardiovascular Research Laboratory, Spaulding Rehabilitation Hospital, Boston, MA (J.W.H., C.O.T.); and Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, MA (C.O.T.).
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Brassard P, Pelletier C, Martin M, Gagné N, Poirier P, Ainslie PN, Caouette M, Bussières JS. Influence of Norepinephrine and Phenylephrine on Frontal Lobe Oxygenation During Cardiopulmonary Bypass in Patients with Diabetes. J Cardiothorac Vasc Anesth 2014; 28:608-17. [DOI: 10.1053/j.jvca.2013.09.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Indexed: 11/11/2022]
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