1
|
L'Écuyer S, Charbonney E, Carrier FM, Rose CF. Implication of Hypotension in the Pathogenesis of Cognitive Impairment and Brain Injury in Chronic Liver Disease. Neurochem Res 2024; 49:1437-1449. [PMID: 36635437 DOI: 10.1007/s11064-022-03854-z] [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: 07/25/2022] [Revised: 09/23/2022] [Accepted: 12/26/2022] [Indexed: 01/14/2023]
Abstract
The incidence of chronic liver disease is on the rise. One of the primary causes of hospital admissions for patients with cirrhosis is hepatic encephalopathy (HE), a debilitating neurological complication. HE is defined as a reversible syndrome, yet there is growing evidence stating that, under certain conditions, HE is associated with permanent neuronal injury and irreversibility. The pathophysiology of HE primarily implicates a strong role for hyperammonemia, but it is believed other pathogenic factors are involved. The fibrotic scarring of the liver during the progression of chronic liver disease (cirrhosis) consequently leads to increased hepatic resistance and circulatory anomalies characterized by portal hypertension, hyperdynamic circulatory state and systemic hypotension. The possible repercussions of these circulatory anomalies on brain perfusion, including impaired cerebral blood flow (CBF) autoregulation, could be implicated in the development of HE and/or permanent brain injury. Furthermore, hypotensive insults incurring during gastrointestinal bleed, infection, or liver transplantation may also trigger or exacerbate brain dysfunction and cell damage. This review will focus on the role of hypotension in the onset of HE as well as in the occurrence of neuronal cell loss in cirrhosis.
Collapse
Affiliation(s)
- Sydnée L'Écuyer
- Hepato-Neuro Laboratory, Centre de recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), 900, rue Saint-Denis - Pavillon R, R08.422 Montréal (Québec), Québec, H2X 0A9, Canada
| | - Emmanuel Charbonney
- Department of Medicine, Critical Care Division, Centre Hospitalier de l'Université de Montréal, Montréal, Canada
| | - François Martin Carrier
- Department of Medicine, Critical Care Division, Centre Hospitalier de l'Université de Montréal, Montréal, Canada
- Department of Anesthesiology, Centre Hospitalier de l'Université de Montréal, Montréal, Canada
- Carrefour de l'innovation et santé des populations , Centre de recherche du Centre hospitalier de l'Université de Montréal (CRCHUM), Montréal, Canada
| | - Christopher F Rose
- Hepato-Neuro Laboratory, Centre de recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), 900, rue Saint-Denis - Pavillon R, R08.422 Montréal (Québec), Québec, H2X 0A9, Canada.
| |
Collapse
|
2
|
Chalifoux N, Ko T, Slovis J, Spelde A, Kilbaugh T, Mavroudis CD. Cerebral Autoregulation: A Target for Improving Neurological Outcomes in Extracorporeal Life Support. Neurocrit Care 2024:10.1007/s12028-024-02002-5. [PMID: 38811513 DOI: 10.1007/s12028-024-02002-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Accepted: 04/18/2024] [Indexed: 05/31/2024]
Abstract
Despite improvements in survival after illnesses requiring extracorporeal life support, cerebral injury continues to hinder successful outcomes. Cerebral autoregulation (CA) is an innate protective mechanism that maintains constant cerebral blood flow in the face of varying systemic blood pressure. However, it is impaired in certain disease states and, potentially, following initiation of extracorporeal circulatory support. In this review, we first discuss patient-related factors pertaining to venovenous and venoarterial extracorporeal membrane oxygenation (ECMO) and their potential role in CA impairment. Next, we examine factors intrinsic to ECMO that may affect CA, such as cannulation, changes in pulsatility, the inflammatory and adaptive immune response, intracranial hemorrhage, and ischemic stroke, in addition to ECMO management factors, such as oxygenation, ventilation, flow rates, and blood pressure management. We highlight potential mechanisms that lead to disruption of CA in both pediatric and adult populations, the challenges of measuring CA in these patients, and potential associations with neurological outcome. Altogether, we discuss individualized CA monitoring as a potential target for improving neurological outcomes in extracorporeal life support.
Collapse
Affiliation(s)
- Nolan Chalifoux
- Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.
- Department of Anesthesiology and Critical Care Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.
- Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.
| | - Tiffany Ko
- Department of Anesthesiology and Critical Care Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Julia Slovis
- Department of Anesthesiology and Critical Care Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Audrey Spelde
- Department of Anesthesiology and Critical Care Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Todd Kilbaugh
- Department of Anesthesiology and Critical Care Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Constantine D Mavroudis
- Division of Cardiothoracic Surgery, Children's Hospital of Philadelphia, Philadelphia, PA, 19104, USA
| |
Collapse
|
3
|
Medicherla C, Pashun R, Al-Mufti F. Review of Cerebral Collateral Circulation and Insight into Cardiovascular Strategies to Limit Collateral Damage in Ischemic Stroke. Cardiol Rev 2024; 32:188-193. [PMID: 37729598 DOI: 10.1097/crd.0000000000000614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 09/22/2023]
Abstract
Cerebral collateral circulation is a dynamic and adaptive process by which alternative vascular pathways supply perfusion to ischemic brain tissue in the event of an arterial occlusion. This complicated network of blood vessels that acts as a natural bypass plays a pivotal role in stroke pathophysiology and has become a key area of study given its significance in stroke treatment and patient outcomes. In this review, we will study the factors influencing the formation, recruitment, and endurance of collateral vessels; discuss imaging modalities for quantitative and qualitative assessment of this network; explore the role of collaterals in stroke management; and highlight several cardiovascular strategies to minimize damage to collaterals and optimize stroke outcomes.
Collapse
Affiliation(s)
| | - Raymond Pashun
- Department of Cardiology, New York University Langone Health, New York, NY
| | - Fawaz Al-Mufti
- Department of Neurology, Neurosurgery, and Radiology, New York Medical College, Valhalla, NY
| |
Collapse
|
4
|
Xue S, Zhou X, Yang ZH, Si XK, Sun X. Stroke-induced damage on the blood-brain barrier. Front Neurol 2023; 14:1248970. [PMID: 37840921 PMCID: PMC10569696 DOI: 10.3389/fneur.2023.1248970] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 08/08/2023] [Indexed: 10/17/2023] Open
Abstract
The blood-brain barrier (BBB) is a functional phenotype exhibited by the neurovascular unit (NVU). It is maintained and regulated by the interaction between cellular and non-cellular matrix components of the NVU. The BBB plays a vital role in maintaining the dynamic stability of the intracerebral microenvironment as a barrier layer at the critical interface between the blood and neural tissues. The large contact area (approximately 20 m2/1.3 kg brain) and short diffusion distance between neurons and capillaries allow endothelial cells to dominate the regulatory role. The NVU is a structural component of the BBB. Individual cells and components of the NVU work together to maintain BBB stability. One of the hallmarks of acute ischemic stroke is the disruption of the BBB, including impaired function of the tight junction and other molecules, as well as increased BBB permeability, leading to brain edema and a range of clinical symptoms. This review summarizes the cellular composition of the BBB and describes the protein composition of the barrier functional junction complex and the mechanisms regulating acute ischemic stroke-induced BBB disruption.
Collapse
Affiliation(s)
| | | | | | | | - Xin Sun
- Stroke Center, Department of Neurology, The First Hospital of Jilin University, Changchun, China
| |
Collapse
|
5
|
Mitchell JW, Gillette MU. Development of circadian neurovascular function and its implications. Front Neurosci 2023; 17:1196606. [PMID: 37732312 PMCID: PMC10507717 DOI: 10.3389/fnins.2023.1196606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Accepted: 08/14/2023] [Indexed: 09/22/2023] Open
Abstract
The neurovascular system forms the interface between the tissue of the central nervous system (CNS) and circulating blood. It plays a critical role in regulating movement of ions, small molecules, and cellular regulators into and out of brain tissue and in sustaining brain health. The neurovascular unit (NVU), the cells that form the structural and functional link between cells of the brain and the vasculature, maintains the blood-brain interface (BBI), controls cerebral blood flow, and surveils for injury. The neurovascular system is dynamic; it undergoes tight regulation of biochemical and cellular interactions to balance and support brain function. Development of an intrinsic circadian clock enables the NVU to anticipate rhythmic changes in brain activity and body physiology that occur over the day-night cycle. The development of circadian neurovascular function involves multiple cell types. We address the functional aspects of the circadian clock in the components of the NVU and their effects in regulating neurovascular physiology, including BBI permeability, cerebral blood flow, and inflammation. Disrupting the circadian clock impairs a number of physiological processes associated with the NVU, many of which are correlated with an increased risk of dysfunction and disease. Consequently, understanding the cell biology and physiology of the NVU is critical to diminishing consequences of impaired neurovascular function, including cerebral bleeding and neurodegeneration.
Collapse
Affiliation(s)
- Jennifer W. Mitchell
- Department of Cell and Developmental Biology, University of Illinois Urbana-Champaign, Urbana, IL, United States
- Neuroscience Program, University of Illinois Urbana-Champaign, Urbana, IL, United States
- Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL, United States
| | - Martha U. Gillette
- Department of Cell and Developmental Biology, University of Illinois Urbana-Champaign, Urbana, IL, United States
- Neuroscience Program, University of Illinois Urbana-Champaign, Urbana, IL, United States
- Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL, United States
- Department of Molecular and Integrative Physiology, University of Illinois Urbana-Champaign, Urbana, IL, United States
- Carle-Illinois College of Medicine, University of Illinois Urbana-Champaign, Urbana, IL, United States
| |
Collapse
|
6
|
Sagirov AF, Sergeev TV, Shabrov AV, Yurov AY, Guseva NL, Agapova EA. Postural influence on intracranial fluid dynamics: an overview. J Physiol Anthropol 2023; 42:5. [PMID: 37055862 PMCID: PMC10100470 DOI: 10.1186/s40101-023-00323-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 04/01/2023] [Indexed: 04/15/2023] Open
Abstract
This review focuses on the effects of different body positions on intracranial fluid dynamics, including cerebral arterial and venous flow, cerebrospinal fluid (CSF) hydrodynamics, and intracranial pressure (ICP). It also discusses research methods used to quantify these effects. Specifically, the implications of three types of body positions (orthostatic, supine, and antiorthostatic) on cerebral blood flow, venous outflow, and CSF circulation are explored, with a particular emphasis on cerebrovascular autoregulation during microgravity and head-down tilt (HDT), as well as posture-dependent changes in cerebral venous and CSF flow, ICP, and intracranial compliance (ICC). The review aims to provide a comprehensive analysis of intracranial fluid dynamics during different body positions, with the potential to enhance our understanding of intracranial and craniospinal physiology.
Collapse
Affiliation(s)
- Arlan Faritovich Sagirov
- Department of Ecological Physiology, Federal State Budgetary Scientific Institution "Institute of Experimental Medicine", 12 Academic Pavlov St, Saint-Petersburg, 197022, Russia.
| | - Timofey Vladimirovich Sergeev
- Department of Ecological Physiology, Federal State Budgetary Scientific Institution "Institute of Experimental Medicine", 12 Academic Pavlov St, Saint-Petersburg, 197022, Russia
| | - Aleksandr Vladimirovich Shabrov
- Department of Ecological Physiology, Federal State Budgetary Scientific Institution "Institute of Experimental Medicine", 12 Academic Pavlov St, Saint-Petersburg, 197022, Russia
| | - Andrey Yur'evich Yurov
- Department of Ecological Physiology, Federal State Budgetary Scientific Institution "Institute of Experimental Medicine", 12 Academic Pavlov St, Saint-Petersburg, 197022, Russia
| | - Nadezhda Leonidovna Guseva
- Department of Ecological Physiology, Federal State Budgetary Scientific Institution "Institute of Experimental Medicine", 12 Academic Pavlov St, Saint-Petersburg, 197022, Russia
| | - Elizaveta Aleksandrovna Agapova
- Department of Ecological Physiology, Federal State Budgetary Scientific Institution "Institute of Experimental Medicine", 12 Academic Pavlov St, Saint-Petersburg, 197022, Russia
| |
Collapse
|
7
|
Wei Z, Li Y, Bibic A, Duan W, Xu J, Lu H. Toward accurate cerebral blood flow estimation in mice after accounting for anesthesia. Front Physiol 2023; 14:1169622. [PMID: 37123257 PMCID: PMC10130671 DOI: 10.3389/fphys.2023.1169622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Accepted: 04/03/2023] [Indexed: 05/02/2023] Open
Abstract
Purpose: To improve the accuracy of cerebral blood flow (CBF) measurement in mice by accounting for the anesthesia effects. Methods: The dependence of CBF on anesthesia dose and time was investigated by simultaneously measuring respiration rate (RR) and heart rate (HR) under four different anesthetic regimens. Quantitative CBF was measured by a phase-contrast (PC) MRI technique. RR was evaluated with a mouse monitoring system (MouseOX) while HR was determined using an ultrashort-TE MRI sequence. CBF, RR, and HR were recorded dynamically with a temporal resolution of 1 min in a total of 19 mice. Linear regression models were used to investigate the relationships among CBF, anesthesia dose, RR, and HR. Results: CBF, RR, and HR all showed a significant dependence on anesthesia dose (p < 0.0001). However, the dose in itself was insufficient to account for the variations in physiological parameters, in that they showed a time-dependent change even for a constant dose. RR and HR together can explain 52.6% of the variations in CBF measurements, which is greater than the amount of variance explained by anesthesia dose (32.4%). Based on the multi-parametric regression results, a model was proposed to correct the anesthesia effects in mouse CBF measurements, specificallyC B F c o r r e c t e d = C B F + 0.58 R R - 0.41 H R - 32.66 D o s e . We also reported awake-state CBF in mice to be 142.0 ± 8.8 mL/100 g/min, which is consistent with the model-predicted value. Conclusion: The accuracy of CBF measurement in mice can be improved by using a correction model that accounts for respiration rate, heart rate, and anesthesia dose.
Collapse
Affiliation(s)
- Zhiliang Wei
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, United States
| | - Yuguo Li
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, United States
| | - Adnan Bibic
- F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, United States
| | - Wenzhen Duan
- Division of Neurobiology, Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Jiadi Xu
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, United States
| | - Hanzhang Lu
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, United States
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| |
Collapse
|
8
|
Becker S, Klein F, König K, Mathys C, Liman T, Witt K. Assessment of dynamic cerebral autoregulation in near-infrared spectroscopy using short channels: A feasibility study in acute ischemic stroke patients. Front Neurol 2022; 13:1028864. [PMID: 36479048 PMCID: PMC9719939 DOI: 10.3389/fneur.2022.1028864] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 11/04/2022] [Indexed: 10/07/2023] Open
Abstract
Introduction In acute ischemic stroke, progressive impairment of cerebral autoregulation (CA) is frequent and associated with unfavorable outcomes. Easy assessment of cerebral blood flow and CA in stroke units bedside tools like near-infrared spectroscopy (NIRS) might improve early detection of CA deterioration. This study aimed to assess dynamic CA with multichannel CW-NIRS in acute ischemic stroke (AIS) patients compared to agematched healthy controls. Methods CA reaction was amplified by changes in head of bed position. Long- and short channels were used to monitor systemic artery pressure- and intracranial oscillations simultaneously. Gain and phase shift in spontaneous low- and very low-frequency oscillations (LFO, VLFO) of blood pressure were assessed. Results A total of 54 participants, 27 with AIS and 27 age-matched controls were included. Gain was significantly lower in the AIS group in the LFO range (i) when the upper body was steadily elevated to 30. and (ii) after its abrupt elevation to 30°. No other differences were found between groups. Discussion This study demonstrates the feasibility of NIRS short channels to measure CA in AIS patients in one single instrument. A lower gain in AIS might indicate decreased CA activity in this pilot study, but further studies investigating the role of NIRS short channels in AIS are needed.
Collapse
Affiliation(s)
- Sabeth Becker
- Department of Neurology, School of Medicine and Health Sciences, Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
| | - Franziska Klein
- Neurocognition and Functional Neurorehabilitation Group, Neuropsychology Lab, Department of Psychology, Faculty of Medicine and Health Sciences, University of Oldenburg, Oldenburg, Germany
| | - Katja König
- Department of Neurology, School of Medicine and Health Sciences, Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
- University Clinic for Neurology, Evangelical Hospital, Oldenburg, Germany
| | - Christian Mathys
- Institute of Radiology and Neuroradiology, Evangelical Hospital, Oldenburg, Germany
- Research Centre Neurosensory Science, Department of Human Medicine, Faculty of Medicine and Health Sciences, University of Oldenburg, Oldenburg, Germany
| | - Thomas Liman
- Department of Neurology, School of Medicine and Health Sciences, Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
- University Clinic for Neurology, Evangelical Hospital, Oldenburg, Germany
| | - Karsten Witt
- Department of Neurology, School of Medicine and Health Sciences, Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
- University Clinic for Neurology, Evangelical Hospital, Oldenburg, Germany
- Institute of Radiology and Neuroradiology, Evangelical Hospital, Oldenburg, Germany
| |
Collapse
|
9
|
A novel computational model for cerebral blood flow rate control mechanisms to evaluate physiological cases. Biomed Signal Process Control 2022. [DOI: 10.1016/j.bspc.2022.103851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
10
|
Lehrer H, Dayan I, Elkayam K, Kfir A, Bierman U, Front L, Catz A, Aidinoff E. Responses to stimuli in the 'snoezelen' room in unresponsive wakefulness or in minimally responsive state. Brain Inj 2022; 36:1167-1175. [PMID: 35978560 DOI: 10.1080/02699052.2022.2110286] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
BACKGROUND Sensory stimulation in Snoezelen room increased responsiveness after brain injury and dementia. OBJECTIVE To explore the physiological and clinical effects of Snoezelen stimulation in persons with unresponsive wakefulness syndrome or minimally conscious state (UWS or MCS). DESIGN A comparative prospective observational cohort study. METHODS Ten patients with UWS and 25 in MCS were exposed to consecutive stimuli involving the 5 senses in a Snoezelen room. Heart rate (HR) and cerebral blood flow velocity (CBFV), and scores of the Loewenstein communication scale (LCS) were obtained before and during or after the stimuli. RESULTS The stimuli increased HR values and decreased left hemisphere CBFV values in patients with MCS (p < 0.05). Stimulation increased LCS scores (from 28.48 ± 6.55 to 31.13 ± 7.14; p < 0.001) in patients with MCS, but not in the UWS group. LCS gain correlated with HR and right hemisphere CBFV gains in patients with MCS (r = 0.439 and 0.636 respectively, p < 0.05). CONCLUSIONS Snoezelen stimulation induced immediate improvement in communication and physiological changes in patients with MSC, and had a minor physiological effect in patients with UWS. If additional studies support these findings, it will be possible to suggest that Snoezelen stimulation can affect arousal, and possibly improve functioning.
Collapse
Affiliation(s)
- Hiela Lehrer
- Departments of Intensive Care for Consciousness Rehabilitation and Spinal Rehabilitation, Loewenstein Rehabilitation Medical Center, Raanana, Israel
| | - Ilil Dayan
- Departments of Intensive Care for Consciousness Rehabilitation and Spinal Rehabilitation, Loewenstein Rehabilitation Medical Center, Raanana, Israel
| | - Keren Elkayam
- Departments of Intensive Care for Consciousness Rehabilitation and Spinal Rehabilitation, Loewenstein Rehabilitation Medical Center, Raanana, Israel
| | - Adi Kfir
- Departments of Intensive Care for Consciousness Rehabilitation and Spinal Rehabilitation, Loewenstein Rehabilitation Medical Center, Raanana, Israel
| | - Uri Bierman
- Departments of Intensive Care for Consciousness Rehabilitation and Spinal Rehabilitation, Loewenstein Rehabilitation Medical Center, Raanana, Israel
| | - Lilach Front
- Departments of Intensive Care for Consciousness Rehabilitation and Spinal Rehabilitation, Loewenstein Rehabilitation Medical Center, Raanana, Israel
| | - Amiram Catz
- Departments of Intensive Care for Consciousness Rehabilitation and Spinal Rehabilitation, Loewenstein Rehabilitation Medical Center, Raanana, Israel.,Sackler Faculty of Medicine, Rehabilitation Department, Tel Aviv University, Tel Aviv, Israel
| | - Elena Aidinoff
- Departments of Intensive Care for Consciousness Rehabilitation and Spinal Rehabilitation, Loewenstein Rehabilitation Medical Center, Raanana, Israel.,Sackler Faculty of Medicine, Rehabilitation Department, Tel Aviv University, Tel Aviv, Israel
| |
Collapse
|
11
|
Investigating the association between depression and cerebral haemodynamics-A systematic review and meta-analysis. J Affect Disord 2022; 299:144-158. [PMID: 34800572 DOI: 10.1016/j.jad.2021.11.037] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 10/25/2021] [Accepted: 11/14/2021] [Indexed: 01/18/2023]
Abstract
BACKGROUND Vascular mechanisms may play a role in depression. The aim of this review is to summarise the evidence on alterations in cerebral haemodynamics in depression. METHODS MEDLINE (1946- present), Embase (1947-present), Web of Science (1970-present), PsycINFO (1984-present), CINAHL (1976-present) and CENTRAL were searched using a predefined search strategy. A meta-analysis was conducted in four groups: 1) global cerebral blood flow (CBF) in ml/min/100 g, 2) CBF velocity (CBFv) in cm/s (maximum flow of left middle cerebral artery, 3) combined CBF and CBFv, 4) Ratio of uptake of Tc 99 m HMPAO (region of interest compared to whole brain). Data are presented as mean difference or standardised mean difference and 95% confidence interval (95% CI). A narrative synthesis of the remaining studies was performed. RESULTS 87 studies were included. CBF was significantly reduced in depressed patients compared to HC [15 studies, 538 patients, 416 HC, MD: -2.24 (95% CI -4.12, -0.36), p = 0.02, I2 = 64%]. There were no statistically significant differences in other parameters. The narrative synthesis revealed variable changes in CBF in depressed patients, particularly affecting the anterior cingulate and prefrontal cortices. LIMITATIONS There were various sources of heterogeneity including the severity of depression, use of antidepressant medication, imaging modality used and reporting of outcomes. All of these factors made direct comparisons between studies difficult. CONCLUSIONS The reduction in CBF in depressed patients compared to HCs may indicate a role for assessment and CBF altering interventions in high-risk groups. However, results were inconsistent across studies, warranting further work to investigate specific subgroups.
Collapse
|
12
|
Hughes WE, Hockenberry J, Miller B, Sorokin A, Beyer AM. Modulation of p66Shc impairs cerebrovascular myogenic tone in low renin but not low nitric oxide models of systemic hypertension. Am J Physiol Heart Circ Physiol 2021; 321:H1096-H1102. [PMID: 34714691 PMCID: PMC8834231 DOI: 10.1152/ajpheart.00542.2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 10/25/2021] [Accepted: 10/26/2021] [Indexed: 11/22/2022]
Abstract
Cerebral blood flow and perfusion are tightly maintained through autoregulation despite changes in transmural pressure. Oxidative stress impairs cerebral blood flow, precipitating cerebrovascular events. Phosphorylation of the adaptor protein p66Shc increases mitochondrial-derived oxidative stress. The effect of p66Shc gain or loss of function in nonhypertensive rats is unclear. We hypothesized that p66Shc gain of function would impair autoregulation of cerebral microcirculation under physiological and pathological conditions. Three previously established transgenic [salt-sensitive (SS) background] p66Shc rats were used, p66-Del/SS (express p66Shc with a nine-amino acid deletion), p66Shc-knockout (KO)/SS (frameshift premature termination codon), and p66Shc signaling and knock-in substitution of Ser36Ala (p66Shc-S36A)/SS (substitution of Ser36Ala). The p66Shc-Del were also bred on Sprague-Dawley (SD) backgrounds (p66-Del/SD), and a subset was exposed to a hypertensive stimulus [NG-nitro-l-arginine methyl ester (l-NAME)] for 4 wk. Active and passive diameters to increasing transmural pressure were measured and myogenic tone was calculated in all groups (SS and SD). Myogenic responses to increasing pressure were impaired in p66Shc-Del/SS rats relative to wild-type (WT)/SS and knock-in substitution of Ser36Ala (S36A; P < 0.05). p66-Del/SD rats did not demonstrate changes in active/passive diameters or myogenic tone relative to WT/SD but did demonstrate attenuated passive diameter responses to higher transmural pressure relative to p66-Del/SS. Four weeks of a hypertensive stimulus (l-NAME) did not alter active or passive diameter responses to increasing transmural pressure (P = 0.86-0.99), but increased myogenic responses relative to p66-Del/SD (P < 0.05). Collectively, we demonstrate the functional impact of p66Shc within the cerebral circulation and demonstrate that the genetic background of p66Shc rats largely drives changes in cerebrovascular function.NEW & NOTEWORTHY We demonstrate that the modulation of p66Shc signaling impairs cerebral artery myogenic tone in a low renin model of hypertension. This impairment is dependent upon the genetic background, as modulated p66Shc signaling in Sprague-Dawley rats does not impair cerebral artery myogenic tone.
Collapse
Affiliation(s)
- William E Hughes
- Department of Medicine and Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Joe Hockenberry
- Department of Medicine and Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Bradley Miller
- Department of Medicine and Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Andrey Sorokin
- Department of Medicine and Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Andreas M Beyer
- Department of Medicine and Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin
| |
Collapse
|
13
|
Kuszynski DS, Christian BD, Dorrance AM, Lauver DA. Clopidogrel treatment inhibits P2Y 2-Mediated constriction in the rabbit middle cerebral artery. Eur J Pharmacol 2021; 911:174545. [PMID: 34606835 DOI: 10.1016/j.ejphar.2021.174545] [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: 05/04/2021] [Revised: 09/28/2021] [Accepted: 09/29/2021] [Indexed: 11/28/2022]
Abstract
Clopidogrel is an effective purinergic 2Y12 receptor (P2Y12) antagonist used to prevent arterial thrombosis, but its use is associated with adverse bleeding. Clinical studies have demonstrated that clopidogrel users have an increased risk of cerebral microbleeds and intracerebral hemorrhage. Our previous studies suggest that non-platelet mechanisms mediate these adverse bleeding events; we hypothesize that clopidogrel or one of its metabolites interacts with blood vessels directly to cause bleeding. New Zealand white rabbits (1.9-2.7 kg) were treated orally with vehicle or clopidogrel (3 or 10 mg/kg) for three days. On the fourth day, the rabbits were anesthetized for blood collection and then euthanized. The brain was collected, and the middle cerebral arteries were isolated. We used light transmission aggregometry and pressure myography to elucidate the mechanisms of the off-target effects associated with clopidogrel treatment. We confirmed that inhibition of P2Y12 activation by clopidogrel inhibited ADP-induced platelet aggregation but had no impact on P2Y12-independent arachidonic acid- or collagen-induced platelet aggregation. Analysis of middle cerebral arteries from clopidogrel treated rabbits showed that clopidogrel did not affect P2Y4, P2Y6, and P2Y14 receptor-mediated contraction but attenuated the contractile response after P2Y2 receptor activation. Further analysis determined P2Y2-mediated constriction was endothelium-dependent. Vasoconstriction is a primary component of hemostasis, and impaired vasoconstriction can prolong bleeding. These results suggest clopidogrel inhibits the endothelial P2Y2 receptor in the middle cerebral artery, which provides a mechanistic explanation for the adverse cerebral bleeding associated with the drug.
Collapse
Affiliation(s)
- Dawn S Kuszynski
- Department of Pharmacology and Toxicology, College of Veterinary Medicine, Michigan State University, East Lansing, MI, USA; Institute of Integrative Toxicology, Michigan State University, East Lansing, MI, USA
| | - Barbara D Christian
- Department of Pharmacology and Toxicology, College of Veterinary Medicine, Michigan State University, East Lansing, MI, USA
| | - Anne M Dorrance
- Department of Pharmacology and Toxicology, College of Osteopathic Medicine, Michigan State University, East Lansing, MI, USA
| | - D Adam Lauver
- Department of Pharmacology and Toxicology, College of Veterinary Medicine, Michigan State University, East Lansing, MI, USA.
| |
Collapse
|
14
|
Barzegar M, Stokes KY, Chernyshev O, Kelley RE, Alexander JS. The Role of the ACE2/MasR Axis in Ischemic Stroke: New Insights for Therapy. Biomedicines 2021; 9:1667. [PMID: 34829896 PMCID: PMC8615891 DOI: 10.3390/biomedicines9111667] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 11/02/2021] [Accepted: 11/08/2021] [Indexed: 12/15/2022] Open
Abstract
Ischemic stroke remains the leading cause of neurologically based morbidity and mortality. Current stroke treatment is limited to two classes of FDA-approved drugs: thrombolytic agents (tissue plasminogen activator (tPA)) and antithrombotic agents (aspirin and heparin), which have a narrow time-window (<4.5 h) for administration after onset of stroke symptoms. While thrombolytic agents restore perfusion, they carry serious risks for hemorrhage, and do not influence damage responses during reperfusion. Consequently, stroke therapies that can suppress deleterious effects of ischemic injury are desperately needed. Angiotensin converting enzyme-2 (ACE2) has been recently suggested to beneficially influence experimental stroke outcomes by converting the vasoconstrictor Ang II into the vasodilator Ang 1-7. In this review, we extensively discuss the protective functions of ACE2-Ang (1-7)-MasR axis of renin angiotensin system (RAS) in ischemic stroke.
Collapse
Affiliation(s)
- Mansoureh Barzegar
- Molecular and Cellular Physiology, Ochsner-LSU Health Sciences Center, Shreveport, LA 71130-3932, USA; (M.B.); (K.Y.S.)
| | - Karen Y. Stokes
- Molecular and Cellular Physiology, Ochsner-LSU Health Sciences Center, Shreveport, LA 71130-3932, USA; (M.B.); (K.Y.S.)
| | - Oleg Chernyshev
- Neurology, Ochsner-LSU Health Sciences Center, Shreveport, LA 71130-3932, USA; (O.C.); (R.E.K.)
| | - Roger E. Kelley
- Neurology, Ochsner-LSU Health Sciences Center, Shreveport, LA 71130-3932, USA; (O.C.); (R.E.K.)
| | - Jonathan S. Alexander
- Molecular and Cellular Physiology, Ochsner-LSU Health Sciences Center, Shreveport, LA 71130-3932, USA; (M.B.); (K.Y.S.)
- Neurology, Ochsner-LSU Health Sciences Center, Shreveport, LA 71130-3932, USA; (O.C.); (R.E.K.)
- Medicine, LSU Health Center, 1501 Kings Highway, Shreveport, LA 71130-3932, USA
- Oral and Maxillofacial Surgery, Ochsner-LSU Health Sciences Center, Shreveport, LA 71130-3932, USA
| |
Collapse
|
15
|
Grey-box modeling and hypothesis testing of functional near-infrared spectroscopy-based cerebrovascular reactivity to anodal high-definition tDCS in healthy humans. PLoS Comput Biol 2021; 17:e1009386. [PMID: 34613970 PMCID: PMC8494321 DOI: 10.1371/journal.pcbi.1009386] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Accepted: 08/28/2021] [Indexed: 12/12/2022] Open
Abstract
Transcranial direct current stimulation (tDCS) has been shown to evoke hemodynamics response; however, the mechanisms have not been investigated systematically using systems biology approaches. Our study presents a grey-box linear model that was developed from a physiologically detailed multi-compartmental neurovascular unit model consisting of the vascular smooth muscle, perivascular space, synaptic space, and astrocyte glial cell. Then, model linearization was performed on the physiologically detailed nonlinear model to find appropriate complexity (Akaike information criterion) to fit functional near-infrared spectroscopy (fNIRS) based measure of blood volume changes, called cerebrovascular reactivity (CVR), to high-definition (HD) tDCS. The grey-box linear model was applied on the fNIRS-based CVR during the first 150 seconds of anodal HD-tDCS in eleven healthy humans. The grey-box linear models for each of the four nested pathways starting from tDCS scalp current density that perturbed synaptic potassium released from active neurons for Pathway 1, astrocytic transmembrane current for Pathway 2, perivascular potassium concentration for Pathway 3, and voltage-gated ion channel current on the smooth muscle cell for Pathway 4 were fitted to the total hemoglobin concentration (tHb) changes from optodes in the vicinity of 4x1 HD-tDCS electrodes as well as on the contralateral sensorimotor cortex. We found that the tDCS perturbation Pathway 3 presented the least mean square error (MSE, median <2.5%) and the lowest Akaike information criterion (AIC, median -1.726) from the individual grey-box linear model fitting at the targeted-region. Then, minimal realization transfer function with reduced-order approximations of the grey-box model pathways was fitted to the ensemble average tHb time series. Again, Pathway 3 with nine poles and two zeros (all free parameters), provided the best Goodness of Fit of 0.0078 for Chi-Square difference test of nested pathways. Therefore, our study provided a systems biology approach to investigate the initial transient hemodynamic response to tDCS based on fNIRS tHb data. Future studies need to investigate the steady-state responses, including steady-state oscillations found to be driven by calcium dynamics, where transcranial alternating current stimulation may provide frequency-dependent physiological entrainment for system identification. We postulate that such a mechanistic understanding from system identification of the hemodynamics response to transcranial electrical stimulation can facilitate adequate delivery of the current density to the neurovascular tissue under simultaneous portable imaging in various cerebrovascular diseases.
Collapse
|
16
|
Kim BJ, Singh N, Menon BK. Hemodynamics of Leptomeningeal Collaterals after Large Vessel Occlusion and Blood Pressure Management with Endovascular Treatment. J Stroke 2021; 23:343-357. [PMID: 34649379 PMCID: PMC8521259 DOI: 10.5853/jos.2021.02446] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 09/03/2021] [Accepted: 09/09/2021] [Indexed: 12/14/2022] Open
Abstract
Endovascular therapy (EVT) is an effective treatment for ischemic stroke due to large vessel occlusion (LVO). Unlike intravenous thrombolysis, EVT enables visualization of the restoration of blood flow, also known as successful reperfusion in real time. However, until successful reperfusion is achieved, the survival of the ischemic brain is mainly dependent on blood flow from the leptomeningeal collaterals (LMC). It plays a critical role in maintaining tissue perfusion after LVO via pre-existing channels between the arborizing pial small arteries or arterioles overlying the cerebral hemispheres. In the ischemic territory where the physiologic cerebral autoregulation is impaired and the pial arteries are maximally dilated within their capacity, the direction and amount of LMC perfusion rely on the systemic perfusion, which can be estimated by measuring blood pressure (BP). After the EVT procedure, treatment focuses on mitigating the risk of hemorrhagic transformation, potentially via BP reduction. Thus, BP management may be a key component of acute care for patients with LVO stroke. However, the guidelines on BP management during and after EVT are limited, mostly due to the scarcity of high-level evidence on this issue. In this review, we aim to summarize the anatomical and physiological characteristics of LMC to maintain cerebral perfusion after acute LVO, along with a landscape summary of the literature on BP management in endovascular treatment. The objective of this review is to describe the mechanistic association between systemic BP and collateral perfusion after LVO and thus provide clinical and research perspectives on this topic.
Collapse
Affiliation(s)
- Beom Joon Kim
- Department of Neurology and Cerebrovascular Center, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Nishita Singh
- Department of Clinical Neurosciences, Foothills Medical Center, University of Calgary, Calgary, AB, Canada
| | - Bijoy K. Menon
- Department of Clinical Neurosciences, Foothills Medical Center, University of Calgary, Calgary, AB, Canada
| |
Collapse
|
17
|
Juliano J, Burkemper B, Lee J, Nelson A, LeTran V, Chu Z, Zhou G, Jiang X, Wang RK, Varma R, Richter GM. Longer Axial Length Potentiates Relationship of Intraocular Pressure and Peripapillary Vessel Density in Glaucoma Patients. Invest Ophthalmol Vis Sci 2021; 62:37. [PMID: 34311470 PMCID: PMC8322720 DOI: 10.1167/iovs.62.9.37] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose The purpose of this study was to investigate how axial length (AL) changes the relationship of intraocular pressure (IOP) with peripapillary vessel density (pVD) in glaucoma versus non-glaucomatous eyes. Methods A population-based, cross-sectional study of 2127 African Americans aged 40 years and older in Inglewood, California, were imaged with 6 × 6-mm optic disc optical coherence tomography angiography scans. There were 1028 healthy subjects (1539 eyes) and 65 subjects with glaucoma (86 eyes) who met inclusion criteria. A multivariable linear mixed effects regression model investigated the relationship of IOP on pVD after controlling for signal strength, retinal nerve fiber layer thickness, and age. These results were stratified by AL groups. Results Higher IOP was a significant predictor of lower pVD among subjects with glaucoma (P = 0.009), but not among healthy subjects (P = 0.26). After stratifying by the sample median AL (23.46 mm), higher IOP was associated with lower pVD among subjects with glaucoma with longer AL (≥ 23.46 mm, P = 0.005), but not among those in the shorter AL (< 23.46 mm, P = 0.45). IOP was not significantly associated with pVD among healthy subjects in either AL stratum. Conclusions Among subjects with glaucoma with longer AL, IOP was significantly associated with pVD. This relationship was not seen among subjects with glaucoma with shorter AL or non-glaucomatous subjects in either AL group. These findings support the hypothesis that disturbed retinal autoregulation may be present in subjects with glaucoma with longer AL. Longitudinal studies are needed to further investigate whether axial elongation increases glaucoma risk by compromising retinal autoregulation.
Collapse
Affiliation(s)
- Joseph Juliano
- USC Roski Eye Institute, Keck School of Medicine of University of Southern California, Los Angeles, California, United States
| | - Bruce Burkemper
- USC Roski Eye Institute, Keck School of Medicine of University of Southern California, Los Angeles, California, United States
| | - Jae Lee
- USC Roski Eye Institute, Keck School of Medicine of University of Southern California, Los Angeles, California, United States
| | - Andrew Nelson
- USC Roski Eye Institute, Keck School of Medicine of University of Southern California, Los Angeles, California, United States
| | - Vivian LeTran
- USC Roski Eye Institute, Keck School of Medicine of University of Southern California, Los Angeles, California, United States
| | - Zhongdi Chu
- Department of Bioengineering, University of Washington, Seattle, Washington, United States
| | - Gabriella Zhou
- Department of Bioengineering, University of Washington, Seattle, Washington, United States
| | - Xuejuan Jiang
- USC Roski Eye Institute, Keck School of Medicine of University of Southern California, Los Angeles, California, United States
| | - Ruikang K Wang
- Department of Bioengineering, University of Washington, Seattle, Washington, United States
| | - Rohit Varma
- Southern California Eye Institute, CHA Hollywood Presbyterian Medical Center, Los Angeles, California, United States
| | - Grace M Richter
- USC Roski Eye Institute, Keck School of Medicine of University of Southern California, Los Angeles, California, United States
| |
Collapse
|
18
|
Fan BB, Sun XC, Huang ZJ, Yang XM, Guo ZD, He ZH. Hypoperfusion assessed by pressure reactivity index is associated with delayed cerebral ischemia after subarachnoid hemorrhage: an observational study. Chin Neurosurg J 2021; 7:16. [PMID: 33648581 PMCID: PMC7923615 DOI: 10.1186/s41016-021-00231-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 01/02/2021] [Indexed: 11/16/2022] Open
Abstract
Background Dysfunction of cerebral autoregulation is one of the pathophysiological mechanisms that causes delayed cerebral ischemia (DCI) after subarachnoid hemorrhage (SAH). Pressure reactivity index (PRx) have been confirmed to reflect the level of cerebral autoregulation and used to derive optimal cerebral perfusion pressure (CPPopt). The goal of this study is to explore the associations between autoregulation, CPPopt, PRx, and DCI. Methods Continuous intracranial pressure (ICP), arterial blood pressure (ABP), and cerebral perfusion pressure (CPP) signals acquired from 61 aSAH patients were retrospectively analyzed. PRx was calculated and collected by Pneumatic computer system. The CPP at the lowest PRx was determined as the CPPopt. The duration of a hypoperfusion event (dHP) was defined as the cumulative time that the PRx was > 0.3 and the CPP was <CPPopt. The duration of CPP more than 10 mmHg below CPPopt (ΔCPPopt < − 10 mmHg) was also used to assess hypoperfusion. The percent of the time of hypoperfusion by dHP and ΔCPPopt < − 10 mmHg (%dHP and %ΔCPPopt) were compared between DCI group and control group, utilizing univariate and multivariable logistic regression. It was the clinical prognosis at 3 months after hemorrhage that was assessed with the modified Rankin Scale, and logistic regression and ROC analysis were used for predictive power for unfavorable outcomes (mRs 3–5). Results Data from 52 patients were included in the final analysis of 61 patients. The mean %dHP in DCI was 29.23% and 10.66% in control. The mean %ΔCPPopt < − 10 mmHg was 22.28%, and 5.90% in control. The %dHP (p < 0.001) and the %ΔCPPopt < − 10mmHg (p < 0.001) was significantly longer in the DCI group. In multivariate logistic regression model, %ΔCPPopt <− 10 mmHg (p < 0.001) and %dHP (p < 0.001) were independent risk factor for predicting DCI, and %ΔCPPopt <− 10 mmHg (p = 0.010) and %dHP (p = 0.026) were independent risk factor for predicting unfavorable outcomes. Conclusions The increase of duration of hypoperfusion events and duration of CPP below CPPopt over 10 mmHg, evaluated as time of lowered CPP, is highly indicative of DCI and unfavorable outcomes.
Collapse
Affiliation(s)
- Bin Bin Fan
- Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Xiao Chuan Sun
- Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
| | - Zhi Jian Huang
- Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Xiao Min Yang
- Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Zong Duo Guo
- Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Zhao Hui He
- Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| |
Collapse
|
19
|
Carrier M, Guilbert J, Lévesque JP, Tremblay MÈ, Desjardins M. Structural and Functional Features of Developing Brain Capillaries, and Their Alteration in Schizophrenia. Front Cell Neurosci 2021; 14:595002. [PMID: 33519380 PMCID: PMC7843388 DOI: 10.3389/fncel.2020.595002] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 12/04/2020] [Indexed: 12/19/2022] Open
Abstract
Schizophrenia affects more than 1% of the world's population and shows very high heterogeneity in the positive, negative, and cognitive symptoms experienced by patients. The pathogenic mechanisms underlying this neurodevelopmental disorder are largely unknown, although it is proposed to emerge from multiple genetic and environmental risk factors. In this work, we explore the potential alterations in the developing blood vessel network which could contribute to the development of schizophrenia. Specifically, we discuss how the vascular network evolves during early postnatal life and how genetic and environmental risk factors can lead to detrimental changes. Blood vessels, capillaries in particular, constitute a dynamic and complex infrastructure distributing oxygen and nutrients to the brain. During postnatal development, capillaries undergo many structural and anatomical changes in order to form a fully functional, mature vascular network. Advanced technologies like magnetic resonance imaging and near infrared spectroscopy are now enabling to study how the brain vasculature and its supporting features are established in humans from birth until adulthood. Furthermore, the contribution of the different neurovascular unit elements, including pericytes, endothelial cells, astrocytes and microglia, to proper brain function and behavior, can be dissected. This investigation conducted among different brain regions altered in schizophrenia, such as the prefrontal cortex, may provide further evidence that schizophrenia can be considered a neurovascular disorder.
Collapse
Affiliation(s)
- Micaël Carrier
- Axe Neurosciences, Centre de recherche du CHU de Québec - Université Laval, Québec, QC, Canada.,Department of Molecular Medicine, Université Laval, Québec, QC, Canada
| | - Jérémie Guilbert
- Axe Oncologie, Centre de recherche du CHU de Québec, Université Laval, Québec, QC, Canada.,Department of Physics, Physical Engineering and Optics, Université Laval, Québec, QC, Canada
| | - Jean-Philippe Lévesque
- Axe Oncologie, Centre de recherche du CHU de Québec, Université Laval, Québec, QC, Canada.,Department of Physics, Physical Engineering and Optics, Université Laval, Québec, QC, Canada
| | - Marie-Ève Tremblay
- Axe Neurosciences, Centre de recherche du CHU de Québec - Université Laval, Québec, QC, Canada.,Department of Molecular Medicine, Université Laval, Québec, QC, Canada.,Division of Medical Sciences, University of Victoria, Victoria, BC, Canada.,Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, BC, Canada.,Neurology and Neurosurgery Department, McGill University, Montréal, QC, Canada
| | - Michèle Desjardins
- Axe Oncologie, Centre de recherche du CHU de Québec, Université Laval, Québec, QC, Canada.,Department of Physics, Physical Engineering and Optics, Université Laval, Québec, QC, Canada
| |
Collapse
|
20
|
Costerus SA, Kortenbout AJ, Vos HJ, Govaert P, Tibboel D, Wijnen RMH, de Jong N, Bosch JG, de Graaff JC. Feasibility of Doppler Ultrasound for Cortical Cerebral Blood Flow Velocity Monitoring During Major Non-cardiac Surgery of Newborns. Front Pediatr 2021; 9:656806. [PMID: 33829005 PMCID: PMC8019737 DOI: 10.3389/fped.2021.656806] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 02/25/2021] [Indexed: 11/13/2022] Open
Abstract
Background and Aim: Newborns needing major surgical intervention are at risk of brain injury and impaired neurodevelopment later in life. Disturbance of cerebral perfusion might be an underlying factor. This study investigates the feasibility of serial transfontanellar ultrasound measurements of the pial arteries during neonatal surgery, and whether perioperative changes in cerebral perfusion can be observed and related to changes in the perioperative management. Methods: In this prospective, observational feasibility study, neonates with congenital diaphragmatic hernia and esophageal atresia scheduled for surgical treatment within the first 28 days of life were eligible for inclusion. We performed transfontanellar directional power Doppler and pulsed wave Doppler ultrasound during major high-risk non-cardiac neonatal surgery. Pial arteries were of interest for the measurements. Extracted Doppler ultrasound parameters were: peak systolic velocity, end diastolic velocity, the resistivity index and pulsatility index. Results: In 10 out of 14 patients it was possible to perform perioperative measurements; the others failed for logistic and technical reasons. In 6 out of 10 patients, it was feasible to perform serial intraoperative transfontanellar ultrasound measurements with directional power Doppler and pulsed wave Doppler of the same pial artery during neonatal surgery. Median peak systolic velocity was ranging between 5.7 and 7.0 cm s-1 and end diastolic velocity between 1.9 and 3.2 cm s-1. In patients with a vasoactive-inotropic score below 12 the trend of peak systolic velocity and end diastolic velocity corresponded with the mean arterial blood pressure trend. Conclusion: Perioperative transfontanellar ultrasound Doppler measurements of the pial arteries are feasible and provide new longitudinal data about perioperative cortical cerebral blood flow velocity. Trial Registration: https://www.trialregister.nl/trial/6972, identifier: NL6972.
Collapse
Affiliation(s)
- Sophie A Costerus
- Department of Paediatric Surgery, Erasmus MC University Medical Centre-Sophia Children's Hospital, Rotterdam, Netherlands
| | - Anna J Kortenbout
- Department of Biomedical Engineering, Thorax Centre, Erasmus MC University Medical Centre, Rotterdam, Netherlands
| | - Hendrik J Vos
- Department of Biomedical Engineering, Thorax Centre, Erasmus MC University Medical Centre, Rotterdam, Netherlands
| | - Paul Govaert
- Department of Neonatology, Ziekenhuis Netwerk Antwerp, Middelheim Antwerp, Belgium
| | - Dick Tibboel
- Department of Paediatric Surgery, Erasmus MC University Medical Centre-Sophia Children's Hospital, Rotterdam, Netherlands
| | - René M H Wijnen
- Department of Paediatric Surgery, Erasmus MC University Medical Centre-Sophia Children's Hospital, Rotterdam, Netherlands
| | - Nico de Jong
- Department of Biomedical Engineering, Thorax Centre, Erasmus MC University Medical Centre, Rotterdam, Netherlands
| | - Johan G Bosch
- Department of Biomedical Engineering, Thorax Centre, Erasmus MC University Medical Centre, Rotterdam, Netherlands
| | - Jurgen C de Graaff
- Department of Anaesthesiology, Erasmus MC University Medical Centre, Rotterdam, Netherlands
| |
Collapse
|
21
|
Dongó E, Kiss L. The Potential Role of Hydrogen Sulfide in the Regulation of Cerebrovascular Tone. Biomolecules 2020; 10:biom10121685. [PMID: 33339440 PMCID: PMC7766080 DOI: 10.3390/biom10121685] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 12/09/2020] [Accepted: 12/14/2020] [Indexed: 01/15/2023] Open
Abstract
A better understanding of the regulation of cerebrovascular circulation is of great importance because stroke and other cerebrovascular diseases represent a major concern in healthcare leading to millions of deaths yearly. The circulation of the central nervous system is regulated in a highly complex manner involving many local factors and hydrogen sulfide (H2S) is emerging as one such possible factor. Several lines of evidence support that H2S takes part in the regulation of vascular tone. Examinations using either exogenous treatment with H2S donor molecules or alterations to the enzymes that are endogenously producing this molecule revealed numerous important findings about its physiological and pathophysiological role. The great majority of these studies were performed on vessel segments derived from the systemic circulation but there are important observations made using cerebral vessels as well. The findings of these experimental works indicate that H2S is having a complex, pleiotropic effect on the vascular wall not only in the systemic circulation but in the cerebrovascular region as well. In this review, we summarize the most important experimental findings related to the potential role of H2S in the cerebral circulation.
Collapse
Affiliation(s)
- Eleni Dongó
- Department of Physiology, Semmelweis University, 1088 Budapest, Hungary
- Department of Neurology, Semmelweis University, 1088 Budapest, Hungary;
| | - Levente Kiss
- Department of Physiology, Semmelweis University, 1088 Budapest, Hungary
- Correspondence: ; Tel.: +36-20-384-5753
| |
Collapse
|
22
|
Courtie E, Veenith T, Logan A, Denniston AK, Blanch RJ. Retinal blood flow in critical illness and systemic disease: a review. Ann Intensive Care 2020; 10:152. [PMID: 33184724 PMCID: PMC7661622 DOI: 10.1186/s13613-020-00768-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 10/23/2020] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Assessment and maintenance of end-organ perfusion are key to resuscitation in critical illness, although there are limited direct methods or proxy measures to assess cerebral perfusion. Novel non-invasive methods of monitoring microcirculation in critically ill patients offer the potential for real-time updates to improve patient outcomes. MAIN BODY Parallel mechanisms autoregulate retinal and cerebral microcirculation to maintain blood flow to meet metabolic demands across a range of perfusion pressures. Cerebral blood flow (CBF) is reduced and autoregulation impaired in sepsis, but current methods to image CBF do not reproducibly assess the microcirculation. Peripheral microcirculatory blood flow may be imaged in sublingual and conjunctival mucosa and is impaired in sepsis. Retinal microcirculation can be directly imaged by optical coherence tomography angiography (OCTA) during perfusion-deficit states such as sepsis, and other systemic haemodynamic disturbances such as acute coronary syndrome, and systemic inflammatory conditions such as inflammatory bowel disease. CONCLUSION Monitoring microcirculatory flow offers the potential to enhance monitoring in the care of critically ill patients, and imaging retinal blood flow during critical illness offers a potential biomarker for cerebral microcirculatory perfusion.
Collapse
Affiliation(s)
- E Courtie
- Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
- Ophthalmology Department, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
- NIHR Surgical Reconstruction and Microbiology Research Centre, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - T Veenith
- Critical Care Unit, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
- Birmingham Acute Care Research Group, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - A Logan
- Axolotl Consulting Ltd, Droitwich, WR9 0JS, Worcestershire, UK
- Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, CV4 7HL, UK
| | - A K Denniston
- Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
- Ophthalmology Department, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
- NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, UK
- Centre for Rare Diseases, Institute of Translational Medicine, Birmingham Health Partners, Birmingham, UK
| | - R J Blanch
- Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK.
- Ophthalmology Department, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK.
- NIHR Surgical Reconstruction and Microbiology Research Centre, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK.
- Academic Department of Military Surgery and Trauma, Royal Centre for Defence Medicine, Birmingham, UK.
| |
Collapse
|
23
|
Nicotine Exposure Along with Oral Contraceptive Treatment in Female Rats Exacerbates Post-cerebral Ischemic Hypoperfusion Potentially via Altered Histamine Metabolism. Transl Stroke Res 2020; 12:817-828. [PMID: 33130995 DOI: 10.1007/s12975-020-00854-5] [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] [Received: 07/13/2020] [Revised: 09/19/2020] [Accepted: 09/23/2020] [Indexed: 10/23/2022]
Abstract
Smoking-derived nicotine (N) and oral contraceptives (OCs) synergistically exacerbate ischemic brain damage in the female, and the underlying mechanisms remain elusive. Our published study showed that N toxicity is exacerbated by OC via altered mitochondrial electron transport chain function. Because mitochondria play an important role in cellular metabolism, we investigated the global metabolomic profile of brains of adolescent and adult female Sprague-Dawley rats exposed to N with or without OC (N+/-OC). Rats were randomly exposed to saline or N+/-OC for 16-21 days followed by random allocation into two cohorts. The first cohort was used to characterize the cortical metabolome. Pathway enrichment analysis showed a significant increase in several histamine metabolites including 1-methylhistamine, 1-methyl-4-imidazoleacetate, and 1-ribosyl-imidazleacetate, along with carnosine and homocarnosine in adolescent and adult animals treated with N and N+OC in relation to respective saline controls, which may be reflective of altered histamine metabolism with nicotine treatment. We also observed reduced levels of the neurotransmitters N-acetyl-aspartyl-glutamate (NAAG), gamma-aminobutyrate (GABA), and N-methyl-GABA in N+OC treatment in adolescent animals. The second cohort underwent bilateral carotid artery occlusion and hypotension followed by cerebral blood flow (CBF) assessment a day later. Autoradiographic images of the brain 24 h after ischemic episodes showed severe reduction in cortical and hippocampal local CBF in N+/-OC-exposed rats compared with saline treated. Because GABA and histamine are critical for CBF maintenance, altered metabolism of these neurotransmitters may be responsible for observed severe post-ischemic hypoperfusion, which in turn exacerbates ischemic brain damage.
Collapse
|
24
|
Goldstein BI, Baune BT, Bond DJ, Chen P, Eyler L, Fagiolini A, Gomes F, Hajek T, Hatch J, McElroy SL, McIntyre RS, Prieto M, Sylvia LG, Tsai S, Kcomt A, Fiedorowicz JG. Call to action regarding the vascular-bipolar link: A report from the Vascular Task Force of the International Society for Bipolar Disorders. Bipolar Disord 2020; 22:440-460. [PMID: 32356562 PMCID: PMC7522687 DOI: 10.1111/bdi.12921] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
OBJECTIVES The association of bipolar disorder with early and excessive cardiovascular disease was identified over a century ago. Nonetheless, the vascular-bipolar link remains underrecognized, particularly with regard to how this link can contribute to our understanding of pathogenesis and treatment. METHODS An international group of experts completed a selective review of the literature, distilling core themes, identifying limitations and gaps in the literature, and highlighting future directions to bridge these gaps. RESULTS The association between bipolar disorder and vascular disease is large in magnitude, consistent across studies, and independent of confounding variables where assessed. The vascular-bipolar link is multifactorial and is difficult to study given the latency between the onset of bipolar disorder, often in adolescence or early adulthood, and subsequent vascular disease, which usually occurs decades later. As a result, studies have often focused on risk factors for vascular disease or intermediate phenotypes, such as structural and functional vascular imaging measures. There is interest in identifying the most relevant mediators of this relationship, including lifestyle (eg, smoking, diet, exercise), medications, and systemic biological mediators (eg, inflammation). Nonetheless, there is a paucity of treatment studies that deliberately engage these mediators, and thus far no treatment studies have focused on engaging vascular imaging targets. CONCLUSIONS Further research focused on the vascular-bipolar link holds promise for gleaning insights regarding the underlying causes of bipolar disorder, identifying novel treatment approaches, and mitigating disparities in cardiovascular outcomes for people with bipolar disorder.
Collapse
Affiliation(s)
- Benjamin I. Goldstein
- Centre for Youth Bipolar DisorderSunnybrook Health Sciences CentreTorontoONCanada,Departments of Psychiatry & PharmacologyFaculty of MedicineUniversity of TorontoTorontoONCanada
| | - Bernhard T. Baune
- Department of Psychiatry and PsychotherapyUniversity of MünsterMünsterGermany,Department of PsychiatryMelbourne Medical SchoolThe University of MelbourneMelbourneVICAustralia,The Florey Institute of Neuroscience and Mental HealthThe University of MelbourneParkvilleVICAustralia
| | - David J. Bond
- Department of Psychiatry and Behavioral ScienceUniversity of Minnesota Medical SchoolMinneapolisMNUSA
| | - Pao‐Huan Chen
- Department of PsychiatryTaipei Medical University HospitalTaipeiTaiwan,Department of PsychiatrySchool of MedicineCollege of MedicineTaipei Medical UniversityTaipeiTaiwan
| | - Lisa Eyler
- Department of PsychiatryUniversity of California San DiegoSan DiegoCAUSA
| | | | - Fabiano Gomes
- Department of PsychiatryQueen’s University School of MedicineKingstonONCanada
| | - Tomas Hajek
- Department of PsychiatryDalhousie UniversityHalifaxNSCanada,National Institute of Mental HealthKlecanyCzech Republic
| | - Jessica Hatch
- Centre for Youth Bipolar DisorderSunnybrook Health Sciences CentreTorontoONCanada,Departments of Psychiatry & PharmacologyFaculty of MedicineUniversity of TorontoTorontoONCanada
| | - Susan L. McElroy
- Department of Psychiatry and Behavioral NeuroscienceUniversity of Cincinnati College of MedicineCincinnatiOHUSA,Lindner Center of HOPEMasonOHUSA
| | - Roger S. McIntyre
- Departments of Psychiatry & PharmacologyFaculty of MedicineUniversity of TorontoTorontoONCanada,Mood Disorders Psychopharmacology UnitUniversity Health NetworkTorontoONCanada
| | - Miguel Prieto
- Department of PsychiatryFaculty of MedicineUniversidad de los AndesSantiagoChile,Mental Health ServiceClínica Universidad de los AndesSantiagoChile,Department of Psychiatry and PsychologyMayo Clinic College of Medicine and ScienceRochesterMNUSA
| | - Louisa G. Sylvia
- Department of PsychiatryMassachusetts General HospitalBostonMAUSA,Department of PsychiatryHarvard Medical SchoolCambridgeMAUSA
| | - Shang‐Ying Tsai
- Department of PsychiatryTaipei Medical University HospitalTaipeiTaiwan,Department of PsychiatrySchool of MedicineCollege of MedicineTaipei Medical UniversityTaipeiTaiwan
| | - Andrew Kcomt
- Hope+Me—Mood Disorders Association of OntarioTorontoONCanada
| | - Jess G. Fiedorowicz
- Departments of Psychiatry, Internal Medicine, & EpidemiologyCarver College of MedicineUniversity of IowaIowa CityIAUSA
| |
Collapse
|
25
|
The Role of Neurovascular System in Neurodegenerative Diseases. Mol Neurobiol 2020; 57:4373-4393. [PMID: 32725516 DOI: 10.1007/s12035-020-02023-z] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 07/14/2020] [Indexed: 12/21/2022]
Abstract
The neurovascular system (NVS), which consisted of neurons, glia, and vascular cells, is a functional and structural unit of the brain. The NVS regulates blood-brain barrier (BBB) permeability and cerebral blood flow (CBF), thereby maintaining the brain's microenvironment for normal functioning, neuronal survival, and information processing. Recent studies have highlighted the role of vascular dysfunction in several neurodegenerative diseases. This is not unexpected since both nervous and vascular systems are functionally interdependent and show close anatomical apposition, as well as similar molecular pathways. However, despite extensive research, the precise mechanism by which neurovascular dysfunction contributes to neurodegeneration remains incomplete. Therefore, understanding the mechanisms of neurovascular dysfunction in disease conditions may allow us to develop potent and effective therapies for prevention and treatment of neurodegenerative diseases. This review article summarizes the current research in the context of neurovascular signaling associated with neurodegenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), and Huntington's disease (HD). We also discuss the potential implication of neurovascular factor as a novel therapeutic target and prognostic marker in patients with neurodegenerative conditions. Graphical Abstract.
Collapse
|
26
|
Kermorgant M, Nasr N, Czosnyka M, Arvanitis DN, Hélissen O, Senard JM, Pavy-Le Traon A. Impacts of Microgravity Analogs to Spaceflight on Cerebral Autoregulation. Front Physiol 2020; 11:778. [PMID: 32719617 PMCID: PMC7350784 DOI: 10.3389/fphys.2020.00778] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 06/15/2020] [Indexed: 12/16/2022] Open
Abstract
It is well known that exposure to microgravity in astronauts leads to a plethora physiological responses such as headward fluid shift, body unloading, and cardiovascular deconditioning. When astronauts return to Earth, some encounter problems related to orthostatic intolerance. An impaired cerebral autoregulation (CA), which could be compromised by the effects of microgravity, has been proposed as one of the mechanisms responsible for orthostatic intolerance. CA is a homeostatic mechanism that maintains cerebral blood flow for any variations in cerebral perfusion pressure by adapting the vascular tone and cerebral vessel diameter. The ground-based models of microgravity are useful tools for determining the gravitational impact of spaceflight on human body. The head-down tilt bed rest (HDTBR), where the subject remains in supine position at −6 degrees for periods ranging from few days to several weeks is the most commonly used ground-based model of microgravity for cardiovascular deconditioning. head-down bed rest (HDBR) is able to replicate cephalic fluid shift, immobilization, confinement, and inactivity. Dry immersion (DI) model is another approach where the subject remains immersed in thermoneutral water covered with an elastic waterproof fabric separating the subject from the water. Regarding DI, this analog imitates absence of any supporting structure for the body, centralization of body fluids, immobilization and hypokinesia observed during spaceflight. However, little is known about the impact of microgravity on CA. Here, we review the fundamental principles and the different mechanisms involved in CA. We also consider the different approaches in order to assess CA. Finally, we focus on the effects of short- and long-term spaceflight on CA and compare these findings with two specific analogs to microgravity: HDBR and DI.
Collapse
Affiliation(s)
- Marc Kermorgant
- INSERM UMR 1048, Institute of Cardiovascular and Metabolic Diseases (I2MC), Toulouse, France
| | - Nathalie Nasr
- INSERM UMR 1048, Institute of Cardiovascular and Metabolic Diseases (I2MC), Toulouse, France.,Department of Neurology, Institute for Neurosciences, Toulouse University Hospital, Toulouse, France
| | - Marek Czosnyka
- Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, Cambridge University Hospital, Cambridge, United Kingdom.,Institute of Electronic Systems, Warsaw University of Technology, Warsaw, Poland
| | - Dina N Arvanitis
- INSERM UMR 1048, Institute of Cardiovascular and Metabolic Diseases (I2MC), Toulouse, France
| | - Ophélie Hélissen
- INSERM UMR 1048, Institute of Cardiovascular and Metabolic Diseases (I2MC), Toulouse, France
| | - Jean-Michel Senard
- INSERM UMR 1048, Institute of Cardiovascular and Metabolic Diseases (I2MC), Toulouse, France.,Department of Clinical Pharmacology, Toulouse University Hospital, Toulouse, France
| | - Anne Pavy-Le Traon
- INSERM UMR 1048, Institute of Cardiovascular and Metabolic Diseases (I2MC), Toulouse, France.,Department of Neurology, Institute for Neurosciences, Toulouse University Hospital, Toulouse, France
| |
Collapse
|
27
|
Abstract
PURPOSE To review the recent developments on the effect of chronic high mean arterial blood pressure (MAP) on cerebral blood flow (CBF) autoregulation and supporting the notion that CBF autoregulation impairment has connection with chronic cerebral diseases. Method: A narrative review of all the relevant papers known to the authors was conducted. Results: Our understanding of the connection between cerebral perfusion impairment and chronic high MAP and cerebral disease is rapidly evolving, from cerebral perfusion impairment being the result of cerebral diseases to being the cause of cerebral diseases. We now better understand the intertwined impact of hypertension and Alzheimer's disease (AD) on cerebrovascular sensory elements and recognize cerebrovascular elements that are more vulnerable to these diseases. Conclusion: We conclude with the suggestion that the sensory elements pathology plays important roles in intertwined mechanisms of chronic high MAP and AD that impact cerebral perfusion.
Collapse
Affiliation(s)
- Noushin Yazdani
- College of Public Health, University of South Florida , Tampa, FL, USA
| | - Mark S Kindy
- Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida , Tampa, FL, USA.,Biomedical Research, James A. Haley VA Medical Center , Tampa, FL, USA
| | - Saeid Taheri
- Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida , Tampa, FL, USA.,Byrd Neuroscience Institute, University of South Florida , Tampa, FL, USA
| |
Collapse
|
28
|
High Arterial Glucose is Associated with Poor Pressure Autoregulation, High Cerebral Lactate/Pyruvate Ratio and Poor Outcome Following Traumatic Brain Injury. Neurocrit Care 2020; 31:526-533. [PMID: 31123993 PMCID: PMC6872512 DOI: 10.1007/s12028-019-00743-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
Background Arterial hyperglycemia is associated with poor outcome in traumatic brain injury (TBI), but the pathophysiology is not completely understood. Previous preclinical and clinical studies have indicated that arterial glucose worsens pressure autoregulation. The aim of this study was to evaluate the relationship of arterial glucose to both pressure reactivity and cerebral energy metabolism. Method This retrospective study was based on 120 patients with severe TBI treated at the Uppsala University hospital, Sweden, 2008–2018. Data from cerebral microdialysis (glucose, pyruvate, and lactate), arterial glucose, and pressure reactivity index (PRx55-15) were analyzed the first 3 days post-injury. Results High arterial glucose was associated with poor outcome/Glasgow Outcome Scale-Extended at 6-month follow-up (r = − 0.201, p value = 0.004) and showed a positive correlation with both PRx55-15 (r = 0.308, p = 0.001) and cerebral lactate/pyruvate ratio (LPR) days 1–3 (r = 0. 244, p = 0.014). Cerebral lactate-to-pyruvate ratio and PRx55-15 had a positive association day 2 (r = 0.219, p = 0.048). Multivariate linear regression analysis showed that high arterial glucose predicted poor pressure autoregulation on days 1 and 2. Conclusions High arterial glucose was associated with poor outcome, poor pressure autoregulation, and cerebral energy metabolic disturbances. The latter two suggest a pathophysiological mechanism for the negative effect of arterial hyperglycemia, although further studies are needed to elucidate if the correlations are causal or confounded by other factors.
Collapse
|
29
|
Bajpai BK, Zakelis R, Deimantavicius M, Imbrasiene D. Comparative Study of Novel Noninvasive Cerebral Autoregulation Volumetric Reactivity Indices Reflected by Ultrasonic Speed and Attenuation as Dynamic Measurements in the Human Brain. Brain Sci 2020; 10:brainsci10040205. [PMID: 32244750 PMCID: PMC7226251 DOI: 10.3390/brainsci10040205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 03/22/2020] [Accepted: 03/26/2020] [Indexed: 11/20/2022] Open
Abstract
This is a comparative study of two novel noninvasive cerebrovascular autoregulation (CA) monitoring methods based on intracranial blood volume (IBV) changes in the human brain. We investigated the clinical applicability of the new volumetric reactivity index (VRx2), reflected by intracranial ultrasonic attenuation dynamics for noninvasive CA monitoring. The CA was determined noninvasively on 43 healthy participants by calculating the volumetric reactivity index (VRx1 from time-of-flight of ultrasound, VRx2 from attenuation of ultrasound). The VRx was calculated as a moving correlation coefficient between the arterial blood pressure and noninvasively measured IBV slow waves. Linear regression between VRx1 and VRx2 (averaged per participants) showed a significant correlation (r = 0.731, p < 0.0001, 95% confidence interval [0.501–0.895]) in data filtered by bandpass filtering. On the other hand, FIR filtering demonstrated a slightly better correlation (r = 0.769, p < 0.0001, 95% confidence interval [0.611–0.909]). The standard deviation of the difference by bandpass filtering was 0.1647 and bias −0.3444; and by FIR filtering 0.1382 and bias −0.3669. This comparative study showed a significant coincidence of the VRx2 index compared to that of VRx1. Hence, VRx2 could be used as an alternative, cost-effective noninvasive cerebrovascular autoregulation index in the same way as VRx1 values are used.
Collapse
Affiliation(s)
- Basant K. Bajpai
- Health Telematics Science Institute, Kaunas University of Technology, LT-51423 Kaunas, Lithuania
- Correspondence: ; Tel.: +370-6478-3364
| | - Rolandas Zakelis
- Health Telematics Science Institute, Kaunas University of Technology, LT-51423 Kaunas, Lithuania
| | - Mantas Deimantavicius
- Health Telematics Science Institute, Kaunas University of Technology, LT-51423 Kaunas, Lithuania
| | - Daiva Imbrasiene
- Department of Health Promotion and Rehabilitation, Lithuanian Sports University, LT-44221 Kaunas, Lithuania
- Institute of Physiology and Pharmacology, Lithuanian University of Health Sciences, LT-44307 Kaunas, Lithuania
| |
Collapse
|
30
|
Duke CB, Sallade TD, Starling J, Pant S, Sheets A, McElwee MK, Young DS, Taylor RA, Keyes LE. Hypertension and Acute Mountain Sickness in Himalayan Trekkers in Nepal: An Observational Cohort Study. Wilderness Environ Med 2020; 31:157-164. [PMID: 32205041 DOI: 10.1016/j.wem.2020.01.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 01/03/2020] [Accepted: 01/15/2020] [Indexed: 01/14/2023]
Abstract
INTRODUCTION A history of preexisting hypertension is common in people participating in mountain activities; however, the relationship between blood pressure (BP), preexisting hypertension, and acute mountain sickness (AMS) is not well studied. We sought to determine these relationships among trekkers in the Everest region of Nepal. METHODS This was a prospective observational cohort study of a convenience sample of adult, nonpregnant volunteers trekking in the Everest Base Camp region in Nepal. We recorded Lake Louise Scores for AMS and measured BP at 2860 m, 3400 m, and 4300 m. The primary outcome was AMS. RESULTS A total of 672 trekkers (including 60 with history of preexisting hypertension) were enrolled at 2860 m. We retained 529 at 3400 m and 363 at 4300 m. At 3400 m, 11% of participants had AMS, and 13% had AMS at 4300 m. We found no relationship between AMS and measured BP values (P>0.05), nor was there any relation of BP to AMS severity as measured by higher Lake Louise Scores (P>0.05). Preexisting hypertension (odds ratio [OR] 0.16; 95% CI 0.025-0.57), male sex (OR 0.59; 95% CI 0.37-0.96), and increased SpO2 (OR 0.93; 95% CI 0.87-0.98) were associated with reduced rates of AMS in multivariate analyses adjusting for known risk factors for AMS. CONCLUSIONS AMS is common in trekkers in Nepal, even at 3400 m. There is no relationship between measured BP and AMS. However, a medical history of hypertension may be associated with a lower risk of AMS. More work is needed to confirm this novel finding.
Collapse
Affiliation(s)
- Charles B Duke
- Department of Emergency Medicine, Yale School of Medicine, New Haven, CT
| | - T Douglas Sallade
- Department of Emergency Medicine, Geisinger Medical Center, Danville, PA
| | - Jennifer Starling
- Department of Emergency Medicine, University of Colorado and Colorado Permanente Medical Group, Saint Joseph Hospital, Denver, CO
| | - Sushil Pant
- Mountain Medicine Society of Nepal, Kathmandu, Nepal
| | | | - Matthew K McElwee
- Department of Medicine, Division of Rheumatic and Autoimmune Diseases, University of Minnesota, Minneapolis, MN
| | - David S Young
- Department of Emergency Medicine, University of Colorado School of Medicine, Aurora, CO
| | | | - Linda E Keyes
- University of Colorado Emergency Medicine and Boulder Emergency Physicians, Boulder, CO.
| |
Collapse
|
31
|
Urquhart EL, Wang X, Liu H, Fadel PJ, Alexandrakis G. Differences in Net Information Flow and Dynamic Connectivity Metrics Between Physically Active and Inactive Subjects Measured by Functional Near-Infrared Spectroscopy (fNIRS) During a Fatiguing Handgrip Task. Front Neurosci 2020; 14:167. [PMID: 32210748 PMCID: PMC7076120 DOI: 10.3389/fnins.2020.00167] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 02/14/2020] [Indexed: 12/11/2022] Open
Abstract
Twenty-three young adults (4 Females, 25.13 ± 3.72 years) performed an intermittent maximal handgrip force task using their dominant hand for 20 min (3.5 s squeeze/6.5 s release, 120 blocks) with concurrent cortical activity imaging by functional Near-Infrared Spectroscopy (fNRIS; OMM-3000, Shimadzu Corp., 111 channels). Subjects were grouped as physically active (n = 10) or inactive (n = 12) based on a questionnaire (active-exercise at least four times a week, inactive- exercise less than two times a week). We explored how motor task fatigue affected the vasomotion-induced oscillations in ΔHbO as measured by fNIRS at each hemodynamic frequency band: endothelial component (0.003–0.02 Hz) associated to microvascular activity, neurogenic component (0.02–0.04 Hz) related to intrinsic neuronal activity, and myogenic component (0.04–0.15 Hz) linked to activity of smooth muscles of arterioles. To help understand how these three neurovascular regulatory mechanisms relate to handgrip task performance we quantified several dynamic fNIRS metrics, including directional phase transfer entropy (dPTE), a computationally efficient and data-driven method used as a marker of information flow between cortical regions, and directional connectivity (DC), a means to compute directionality of information flow between two cortical regions. The relationship between static functional connectivity (SFC) and functional connectivity variability (FCV) was also explored to understand their mutual dependence for each frequency band in the context of handgrip performance as fatigued increased. Our findings ultimately showed differences between subject groups across all fNIRS metrics and hemodynamic frequency bands. These findings imply that physical activity modulates neurovascular control mechanisms at the endogenic, neurogenic, and myogenic frequency bands resulting in delayed fatigue onset and enhanced performance. The dynamic cortical network metrics quantified in this work for young, healthy subjects provides baseline measurements to guide future work on older individuals and persons with impaired cardiovascular health.
Collapse
Affiliation(s)
- Elizabeth L Urquhart
- Bioengineering Department, University of Texas at Arlington, Arlington, TX, United States
| | - Xinlong Wang
- Bioengineering Department, University of Texas at Arlington, Arlington, TX, United States
| | - Hanli Liu
- Bioengineering Department, University of Texas at Arlington, Arlington, TX, United States
| | - Paul J Fadel
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX, United States
| | - George Alexandrakis
- Bioengineering Department, University of Texas at Arlington, Arlington, TX, United States
| |
Collapse
|
32
|
Malhotra A, Castillo-Melendez M, Allison BJ, Sutherland AE, Nitsos I, Pham Y, McDonald CA, Fahey MC, Polglase GR, Jenkin G, Miller SL. Neurovascular effects of umbilical cord blood-derived stem cells in growth-restricted newborn lambs : UCBCs for perinatal brain injury. Stem Cell Res Ther 2020; 11:17. [PMID: 31915068 PMCID: PMC6947982 DOI: 10.1186/s13287-019-1526-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2019] [Revised: 11/28/2019] [Accepted: 12/10/2019] [Indexed: 12/14/2022] Open
Abstract
Background Neonatal ventilation exacerbates brain injury in lambs with fetal growth restriction (FGR), characterized by neuroinflammation and reduced blood-brain barrier integrity, which is normally maintained by the neurovascular unit. We examined whether umbilical cord blood stem cell (UCBC) treatment stabilized the neurovascular unit and reduced brain injury in preterm ventilated FGR lambs. Methods Surgery was performed in twin-bearing pregnant ewes at 88 days’ gestation to induce FGR in one fetus. At 127 days, FGR and appropriate for gestational age (AGA) lambs were delivered, carotid artery flow probes and umbilical lines inserted, lambs intubated and commenced on gentle ventilation. Allogeneic ovine UCBCs (25 × 106 cells/kg) were administered intravenously to lambs at 1 h of life. Lambs were ventilated for 24 h and then euthanized. Results FGR (n = 6) and FGR+UCBC (n = 6) lambs were growth restricted compared to AGA (n = 6) and AGA+UCBC (n = 6) lambs (combined weight, FGR 2.3 ± 0.4 vs. AGA 3.0 ± 0.3 kg; p = 0.0002). UCBC therapy did not alter mean arterial blood pressure or carotid blood flow but decreased cerebrovascular resistance in FGR+UCBC lambs. Circulating TNF-α cytokine levels were lower in FGR+UCBC vs. FGR lambs (p < 0.05). Brain histopathology showed decreased neuroinflammation and oxidative stress, increased endothelial cell proliferation, pericyte stability, and greater integrity of the neurovascular unit in FGR+UCBC vs. FGR lambs. Conclusions Umbilical cord blood stem cell therapy mitigates perinatal brain injury due to FGR and ventilation, and the neuroprotective benefits may be mediated by stabilization of the neurovascular unit.
Collapse
Affiliation(s)
- Atul Malhotra
- Monash Newborn, Monash Children's Hospital, 246 Clayton Road, Clayton, Melbourne, VIC, 3168, Australia. .,Department of Paediatrics, Monash University, Melbourne, Australia. .,The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Australia.
| | - Margie Castillo-Melendez
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Australia.,Department of Obstetrics and Gynaecology, Monash University, Melbourne, Australia
| | - Beth J Allison
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Australia.,Department of Obstetrics and Gynaecology, Monash University, Melbourne, Australia
| | - Amy E Sutherland
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Australia
| | - Ilias Nitsos
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Australia
| | - Yen Pham
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Australia
| | - Courtney A McDonald
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Australia
| | - Michael C Fahey
- Department of Paediatrics, Monash University, Melbourne, Australia.,The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Australia
| | - Graeme R Polglase
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Australia.,Department of Obstetrics and Gynaecology, Monash University, Melbourne, Australia
| | - Graham Jenkin
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Australia.,Department of Obstetrics and Gynaecology, Monash University, Melbourne, Australia
| | - Suzanne L Miller
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Australia.,Department of Obstetrics and Gynaecology, Monash University, Melbourne, Australia
| |
Collapse
|
33
|
Mbagwu SI, Filgueira L. Differential Expression of CD31 and Von Willebrand Factor on Endothelial Cells in Different Regions of the Human Brain: Potential Implications for Cerebral Malaria Pathogenesis. Brain Sci 2020; 10:E31. [PMID: 31935960 PMCID: PMC7016814 DOI: 10.3390/brainsci10010031] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 12/31/2019] [Accepted: 01/03/2020] [Indexed: 12/15/2022] Open
Abstract
Cerebral microvascular endothelial cells (CMVECs) line the vascular system of the brain and are the chief cells in the formation and function of the blood brain barrier (BBB). These cells are heterogeneous along the cerebral vasculature and any dysfunctional state in these cells can result in a local loss of function of the BBB in any region of the brain. There is currently no report on the distribution and variation of the CMVECs in different brain regions in humans. This study investigated microcirculation in the adult human brain by the characterization of the expression pattern of brain endothelial cell markers in different brain regions. Five different brain regions consisting of the visual cortex, the hippocampus, the precentral gyrus, the postcentral gyrus, and the rhinal cortex obtained from three normal adult human brain specimens were studied and analyzed for the expression of the endothelial cell markers: cluster of differentiation 31 (CD31) and von-Willebrand-Factor (vWF) through immunohistochemistry. We observed differences in the expression pattern of CD31 and vWF between the gray matter and the white matter in the brain regions. Furthermore, there were also regional variations in the pattern of expression of the endothelial cell biomarkers. Thus, this suggests differences in the nature of vascularization in various regions of the human brain. These observations also suggest the existence of variation in structure and function of different brain regions, which could reflect in the pathophysiological outcomes in a diseased state.
Collapse
Affiliation(s)
- Smart Ikechukwu Mbagwu
- Anatomy Unit, Department of Oncology, Microbiology and Immunology, Faculty of Science and Medicine, University of Fribourg, 1700 Fribourg, Switzerland
- Department of Anatomy, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, 435101 Nnewi Campus, Nigeria
| | - Luis Filgueira
- Anatomy Unit, Department of Oncology, Microbiology and Immunology, Faculty of Science and Medicine, University of Fribourg, 1700 Fribourg, Switzerland
| |
Collapse
|
34
|
Göttler J, Kaczmarz S, Kallmayer M, Wustrow I, Eckstein HH, Zimmer C, Sorg C, Preibisch C, Hyder F. Flow-metabolism uncoupling in patients with asymptomatic unilateral carotid artery stenosis assessed by multi-modal magnetic resonance imaging. J Cereb Blood Flow Metab 2019; 39:2132-2143. [PMID: 29968499 PMCID: PMC6827123 DOI: 10.1177/0271678x18783369] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Oxygen extraction (OEF), oxidative metabolism (CMRO2), and blood flow (CBF) in the brain, as well as the coupling between CMRO2 and CBF due to cerebral autoregulation are fundamental to brain's health. We used a clinically feasible MRI protocol to assess impairments of these parameters in the perfusion territories of stenosed carotid arteries. Twenty-nine patients with unilateral high-grade carotid stenosis and thirty age-matched healthy controls underwent multi-modal MRI scans. Pseudo-continuous arterial spin labeling (pCASL) yielded absolute CBF, whereas multi-parametric quantitative blood oxygenation level dependent (mqBOLD) modeling allowed imaging of relative OEF and CMRO2. Both CBF and CMRO2 were significantly reduced in the stenosed territory compared to the contralateral side, while OEF was evenly distributed across both hemispheres similarly in patients and controls. The CMRO2-CBF coupling was significantly different between both hemispheres in patients, i.e. significant interhemispheric flow-metabolism uncoupling was observed in patients compared to controls. Given that CBF and CMRO2 are intimately linked to brain function in health and disease, the proposed easily applicable MRI protocol of pCASL and mqBOLD imaging might serve as a valuable tool for early diagnosis of potentially harmful cerebral hemodynamic and metabolic states with the final aim to select clinically asymptomatic patients who would benefit from carotid revascularization therapy.
Collapse
Affiliation(s)
- Jens Göttler
- Department of Radiology & Biomedical Imaging, Magnetic Resonance Research Center, Yale University, New Haven, CT, USA.,Department of Diagnostic and Interventional Neuroradiology, Technische Universität München, Klinikum rechts der Isar, Munich, Germany.,TUM Neuroimaging Center (TUM-NIC), Technische Universität München, Klinikum rechts der Isar, Munich, Germany.,Department of Diagnostic and Interventional Radiology, Technische Universität München, Klinikum rechts der Isar, Munich, Germany
| | - Stephan Kaczmarz
- Department of Radiology & Biomedical Imaging, Magnetic Resonance Research Center, Yale University, New Haven, CT, USA.,Department of Diagnostic and Interventional Neuroradiology, Technische Universität München, Klinikum rechts der Isar, Munich, Germany.,TUM Neuroimaging Center (TUM-NIC), Technische Universität München, Klinikum rechts der Isar, Munich, Germany
| | - Michael Kallmayer
- Department of Vascular and Endovascular Surgery, Technische Universität München, Klinikum rechts der Isar, Munich, Germany
| | - Isabel Wustrow
- I. Medizinische Klinik und Poliklinik, Technische Universität München, Klinikum rechts der Isar, Munich, Germany
| | - Hans-Henning Eckstein
- Department of Vascular and Endovascular Surgery, Technische Universität München, Klinikum rechts der Isar, Munich, Germany
| | - Claus Zimmer
- Department of Diagnostic and Interventional Neuroradiology, Technische Universität München, Klinikum rechts der Isar, Munich, Germany
| | - Christian Sorg
- Department of Diagnostic and Interventional Neuroradiology, Technische Universität München, Klinikum rechts der Isar, Munich, Germany.,TUM Neuroimaging Center (TUM-NIC), Technische Universität München, Klinikum rechts der Isar, Munich, Germany.,Department of Psychiatry, Technische Universität München, Klinikum rechts der Isar, Munich, Germany
| | - Christine Preibisch
- Department of Diagnostic and Interventional Neuroradiology, Technische Universität München, Klinikum rechts der Isar, Munich, Germany.,TUM Neuroimaging Center (TUM-NIC), Technische Universität München, Klinikum rechts der Isar, Munich, Germany.,Clinic for Neurology, Technische Universität München, Klinikum rechts der Isar, Munich, Germany
| | - Fahmeed Hyder
- Department of Radiology & Biomedical Imaging, Magnetic Resonance Research Center, Yale University, New Haven, CT, USA.,Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| |
Collapse
|
35
|
Panerai RB, Hanby MF, Robinson TG, Haunton VJ. Alternative representation of neural activation in multivariate models of neurovascular coupling in humans. J Neurophysiol 2019; 122:833-843. [DOI: 10.1152/jn.00175.2019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Neural stimulation leads to increases in cerebral blood flow (CBF), but simultaneous changes in covariates, such as arterial blood pressure (BP) and [Formula: see text], rule out the use of CBF changes as a reliable marker of neurovascular coupling (NVC) integrity. Healthy subjects performed repetitive (1 Hz) passive elbow flexion with their dominant arm for 60 s. CBF velocity (CBFV) was recorded bilaterally in the middle cerebral artery with transcranial Doppler, BP with the Finometer device, and end-tidal CO2 (EtCO2) with capnography. The simultaneous effects of neural stimulation, BP, and [Formula: see text] on CBFV were expressed with a dynamic multivariate model, using BP, EtCO2, and stimulation [ s( t)] as inputs. Two versions of s( t) were considered: a gate function [ sG( t)] or an orthogonal decomposition [ sO( t)] function. A separate CBFV step response was extracted from the model for each of the three inputs, providing estimates of dynamic cerebral autoregulation [CA; autoregulation index (ARI)], CO2 reactivity [vasomotor reactivity step response (VMRSR)], and NVC [stimulus step response (STIMSR)]. In 56 subjects, 224 model implementations produced excellent predictive CBFV correlation (median r = 0.995). Model-generated sO( t), for both dominant (DH) and nondominant (NDH) hemispheres, was highly significant during stimulation (<10−5) and was correlated with the CBFV change ( r = 0.73, P = 0.0001). The sO( t) explained a greater fraction of CBFV variance (~50%) than sG( t) (44%, P = 0.002). Most CBFV step responses to the three inputs were physiologically plausible, with better agreement for the CBFV-BP step response yielding ARI values of 7.3 for both DH and NDH for sG( t), and 6.9 and 7.4 for sO( t), respectively. No differences between DH and NDH were observed for VMRSR or STIMSR. A new procedure is proposed to represent the contribution from other aspects of CBF regulation than BP and CO2 in response to sensorimotor stimulation, as a tool for integrated, noninvasive, assessment of the multiple influences of dynamic CA, CO2 reactivity, and NVC in humans. NEW & NOTEWORTHY A new approach was proposed to identify the separate contributions of stimulation, arterial blood pressure (BP), and arterial CO2 ([Formula: see text]) to the cerebral blood flow (CBF) response observed in neurovascular coupling (NVC) studies in humans. Instead of adopting an empirical gate function to represent the stimulation input, a model-generated function is derived as part of the modeling process, providing a representation of the NVC response, independent of the contributions of BP or [Formula: see text]. This new marker of NVC, together with the model-predicted outputs for the contributions of BP, [Formula: see text] and stimulation, has considerable potential to both quantify and simultaneously integrate the separate mechanisms involved in CBF regulation, namely, cerebral autoregulation, CO2 reactivity and other contributions.
Collapse
Affiliation(s)
- Ronney B. Panerai
- Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
- National Institute for Health Research Leicester Biomedical Research Centre, University of Leicester, Leicester, United Kingdom
| | - Martha F. Hanby
- Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
| | - Thompson G. Robinson
- Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
- National Institute for Health Research Leicester Biomedical Research Centre, University of Leicester, Leicester, United Kingdom
| | - Victoria J. Haunton
- Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
- National Institute for Health Research Leicester Biomedical Research Centre, University of Leicester, Leicester, United Kingdom
| |
Collapse
|
36
|
Biringer RG. The Role of Eicosanoids in Alzheimer's Disease. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2019; 16:ijerph16142560. [PMID: 31323750 PMCID: PMC6678666 DOI: 10.3390/ijerph16142560] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 07/09/2019] [Accepted: 07/13/2019] [Indexed: 12/21/2022]
Abstract
Alzheimer's disease (AD) is one of the most common neurodegenerative disorders known. Estimates from the Alzheimer's Association suggest that there are currently 5.8 million Americans living with the disease and that this will rise to 14 million by 2050. Research over the decades has revealed that AD pathology is complex and involves a number of cellular processes. In addition to the well-studied amyloid-β and tau pathology, oxidative damage to lipids and inflammation are also intimately involved. One aspect all these processes share is eicosanoid signaling. Eicosanoids are derived from polyunsaturated fatty acids by enzymatic or non-enzymatic means and serve as short-lived autocrine or paracrine agents. Some of these eicosanoids serve to exacerbate AD pathology while others serve to remediate AD pathology. A thorough understanding of eicosanoid signaling is paramount for understanding the underlying mechanisms and developing potential treatments for AD. In this review, eicosanoid metabolism is examined in terms of in vivo production, sites of production, receptor signaling, non-AD biological functions, and known participation in AD pathology.
Collapse
Affiliation(s)
- Roger G Biringer
- College of Osteopathic Medicine, Lake Erie College of Osteopathic Medicine, 5000 Lakewood Ranch Blvd., Bradenton, FL 34211, USA.
| |
Collapse
|
37
|
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: 76] [Impact Index Per Article: 12.7] [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.
Collapse
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.
| |
Collapse
|
38
|
Santisteban MM, Iadecola C. Hypertension, dietary salt and cognitive impairment. J Cereb Blood Flow Metab 2018; 38:2112-2128. [PMID: 30295560 PMCID: PMC6282225 DOI: 10.1177/0271678x18803374] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 08/31/2018] [Indexed: 12/12/2022]
Abstract
Dementia is growing at an alarming rate worldwide. Although Alzheimer disease is the leading cause, over 50% of individuals diagnosed with Alzheimer disease have vascular lesions at autopsy. There has been an increasing appreciation of the pathogenic role of vascular risk factors in cognitive impairment caused by neurodegeneration. Midlife hypertension is a leading risk factor for late-life dementia. Hypertension alters cerebrovascular structure, impairs the major factors regulating the cerebral microcirculation, and promotes Alzheimer pathology. Experimental studies have identified brain perivascular macrophages as the major free radical source mediating neurovascular dysfunction of hypertension. Recent evidence indicates that high dietary salt may also induce cognitive impairment. Contrary to previous belief, the effect is not necessarily associated with hypertension and is mediated by a deficit in endothelial nitric oxide. Collectively, the evidence suggests a remarkable cellular diversity of the impact of vascular risk factors on the cerebral vasculature and cognition. Whereas long-term longitudinal epidemiological studies are needed to resolve the temporal relationships between vascular risk factors and cognitive dysfunction, single-cell molecular studies of the vasculature in animal models will provide a fuller mechanistic understanding. This knowledge is critical for developing new preventive, diagnostic, and therapeutic approaches for these devastating diseases of the mind.
Collapse
Affiliation(s)
- Monica M Santisteban
- Feil Family Brain and Mind Research Institute Weill Cornell Medicine, New York, NY, USA
| | - Costantino Iadecola
- Feil Family Brain and Mind Research Institute Weill Cornell Medicine, New York, NY, USA
| |
Collapse
|
39
|
Toma S, MacIntosh BJ, Swardfager W, Goldstein BI. Cerebral blood flow in bipolar disorder: A systematic review. J Affect Disord 2018; 241:505-513. [PMID: 30149339 DOI: 10.1016/j.jad.2018.08.040] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Revised: 08/01/2018] [Accepted: 08/10/2018] [Indexed: 10/28/2022]
Abstract
BACKGROUND Neuroimaging of cerebral blood flow (CBF) can inform our understanding of the pathophysiology of bipolar disorder (BD) as there is increasing support for the concept that BD is in part a vascular disease. Despite numerous studies examining CBF in BD, there has not yet been a review of the literature on the topic of CBF in BD. METHODS A systematic review of the literature on CBF in BD was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). Studies included measured CBF by single-photon emission computerized tomography (SPECT), positron emission tomography (PET), arterial spin labelling (ASL) or perfusion weighted imaging (PWI) in a group of BD patients. RESULTS Thirty-three studies with a total of 508 subjects with BD and 538 controls were included (n = 15 SPECT; n = 8 PET; n = 7 ASL; n = 1 PWI; n = 2 other). The majority of studies in BD depression and mania reported widespread resting hypoperfusion in cingulate gyrus, frontal, and anterior temporal regions in comparison to healthy controls (HC). Findings in euthymic BD subjects and in symptomatically heterogeneous groups were less consistent. Studies that examined CBF responses to cognitive or emotional stimuli in BD subjects have reported hypoperfusion or different regions involved in comparison to HC. LIMITATIONS Important methodological heterogeneity between studies, and small number of subjects per study. CONCLUSIONS The most consistent findings to date are hypoperfusion in BD mood episodes, and hypoactive CBF responses to emotional or cognitive challenges. Future studies examining CBF are warranted, including prospective studies, studies examining CBF as a treatment target, and multimodal imaging studies.
Collapse
Affiliation(s)
- Simina Toma
- Centre for Youth Bipolar Disorder, Sunnybrook Health Sciences Centre, Toronto, Canada; Department of Psychiatry, University of Toronto, Toronto, Canada
| | - Bradley J MacIntosh
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, Canada; Heart and Stroke Foundation Canadian Partnership for Stroke Recovery, Sunnybrook Health Sciences Centre, Toronto, Canada; Department of Medical Biophysics, University of Toronto, Toronto, Canada; Department of Physical Sciences, Sunnybrook Health Sciences Centre, Toronto, Canada
| | - Walter Swardfager
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, Canada; Heart and Stroke Foundation Canadian Partnership for Stroke Recovery, Sunnybrook Health Sciences Centre, Toronto, Canada; Department of Pharmacology, University of Toronto, Toronto, Canada
| | - Benjamin I Goldstein
- Centre for Youth Bipolar Disorder, Sunnybrook Health Sciences Centre, Toronto, Canada; Department of Psychiatry, University of Toronto, Toronto, Canada; Department of Pharmacology, University of Toronto, Toronto, Canada.
| |
Collapse
|
40
|
Shokri-Kojori E, Tomasi D, Volkow ND. An Autonomic Network: Synchrony Between Slow Rhythms of Pulse and Brain Resting State Is Associated with Personality and Emotions. Cereb Cortex 2018; 28:3356-3371. [PMID: 29955858 PMCID: PMC6095212 DOI: 10.1093/cercor/bhy144] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Revised: 05/15/2018] [Accepted: 05/18/2018] [Indexed: 12/14/2022] Open
Abstract
The sympathetic system's role in modulating vasculature and its influence on emotions and personality led us to test the hypothesis that interactions between brain resting-state networks (RSNs) and pulse amplitude (indexing sympathetic activity) would be associated with emotions and personality. In 203 participants, we characterized RSN spatiotemporal characteristics, and phase-amplitude associations of RSN fluctuations with pulse and respiratory recordings. We found that RSNs are spatially reproducible within participants and were temporally associated with low frequencies (LFs < 0.1 Hz) in physiological signals. LF fluctuations in pulse amplitude were not related to cardiac electrical activity and preceded LF fluctuations in RSNs, while LF respiratory amplitude fluctuations followed LF fluctuations in RSNs. LF phase dispersion (PD) (lack of synchrony) between RSNs and pulse (PDpulse) (not respiratory) correlated with the common variability in measures of personality and emotions, with more synchrony being associated with more positive temperamental characteristics. Voxel-level PDpulse mapping revealed an "autonomic brain network," including sensory cortices and dorsal attention stream, with significant interactions with peripheral signals. Here, we uncover associations between pulse signal amplitude (presumably of sympathetic origin) and brain resting state, suggesting that interactions between central and autonomic nervous systems are important for characterizing personality and emotions.
Collapse
Affiliation(s)
- Ehsan Shokri-Kojori
- Laboratory of Neuroimaging, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Dardo Tomasi
- Laboratory of Neuroimaging, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Nora D Volkow
- Laboratory of Neuroimaging, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
- National Institute on Drug Abuse, National Institutes of Health, Bethesda, MD, USA
| |
Collapse
|
41
|
Andersen AV, Simonsen SA, Schytz HW, Iversen HK. Assessing low-frequency oscillations in cerebrovascular diseases and related conditions with near-infrared spectroscopy: a plausible method for evaluating cerebral autoregulation? NEUROPHOTONICS 2018; 5:030901. [PMID: 30689678 PMCID: PMC6156398 DOI: 10.1117/1.nph.5.3.030901] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 08/02/2018] [Indexed: 05/08/2023]
Abstract
BACKGROUND Cerebral autoregulation (CA) is the brain's ability to always maintain an adequate and relatively constant blood supply, which is often impaired in cerebrovascular diseases. Near-infrared spectroscopy (NIRS) examines oxygenated hemoglobin (OxyHb) in the cerebral cortex. Low- and very low-frequency oscillations ( LFOs ≈ 0.1 Hz and VLFOs ≈ 0.05 to 0.01 Hz) in OxyHb have been proposed to reflect CA. AIM To systematically review published results on OxyHb LFOs and VLFOs in cerebrovascular diseases and related conditions measured with NIRS. APPROACH A systematic search was performed in the MEDLINE database, which generated 36 studies relevant for inclusion. RESULTS Healthy people have relatively stable LFOs. LFO amplitude seems to reflect myogenic CA being decreased by vasomotor paralysis in stroke, by smooth muscle damage or as compensatory action in other conditions but can also be influenced by the sympathetic tone. VLFO amplitude is believed to reflect neurogenic and metabolic CA and is lower in stroke, atherosclerosis, and with aging. Both LFO and VLFO synchronizations appear disturbed in stroke, while the former is also altered in internal carotid stenosis and hypertension. CONCLUSION We conclude that amplitudes of LFOs and VLFOs are relatively robust measures for evaluating mechanisms of CA and synchronization analyses can show temporal disruption of CA. Further research and more coherent methodologies are needed.
Collapse
Affiliation(s)
- Adam Vittrup Andersen
- Rigshospitalet, Department of Neurology, Glostrup, Denmark
- University of Copenhagen, Department of Clinical Medicine, Copenhagen, Denmark
- Address all correspondence to: Adam Vittrup Andersen, E-mail:
| | - Sofie Amalie Simonsen
- Rigshospitalet, Department of Neurology, Glostrup, Denmark
- University of Copenhagen, Department of Clinical Medicine, Copenhagen, Denmark
| | - Henrik Winther Schytz
- Rigshospitalet, Department of Neurology, Glostrup, Denmark
- University of Copenhagen, Department of Clinical Medicine, Copenhagen, Denmark
| | - Helle Klingenberg Iversen
- Rigshospitalet, Department of Neurology, Glostrup, Denmark
- University of Copenhagen, Department of Clinical Medicine, Copenhagen, Denmark
| |
Collapse
|
42
|
Marie C, Pedard M, Quirié A, Tessier A, Garnier P, Totoson P, Demougeot C. Brain-derived neurotrophic factor secreted by the cerebral endothelium: A new actor of brain function? J Cereb Blood Flow Metab 2018; 38:935-949. [PMID: 29557702 PMCID: PMC5998997 DOI: 10.1177/0271678x18766772] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Low cerebral levels of brain-derived neurotrophic factor (BDNF), which plays a critical role in many brain functions, have been implicated in neurodegenerative, neurological and psychiatric diseases. Thus, increasing BDNF levels in the brain is considered an attractive possibility for the prevention/treatment of various brain diseases. To date, BDNF-based therapies have largely focused on neurons. However, given the cross-talk between endothelial cells and neurons and recent evidence that BDNF expressed by the cerebral endothelium largely accounts for BDNF levels present in the brain, it is likely that BDNF-based therapies would be most effective if they also targeted the cerebral endothelium. In this review, we summarize the available knowledge about the biology and actions of BDNF derived from endothelial cells of the cerebral microvasculature and we emphasize the remaining gaps and shortcomings.
Collapse
Affiliation(s)
- Christine Marie
- 1 INSERM U1093, Univ. Bourgogne Franche-Comté, Dijon, France
| | - Martin Pedard
- 1 INSERM U1093, Univ. Bourgogne Franche-Comté, Dijon, France.,2 Service de Neurologie, CHRU, Dijon, France
| | - Aurore Quirié
- 1 INSERM U1093, Univ. Bourgogne Franche-Comté, Dijon, France
| | - Anne Tessier
- 1 INSERM U1093, Univ. Bourgogne Franche-Comté, Dijon, France
| | | | - Perle Totoson
- 3 EA4267 PEPITE, FHU INCREASE, Univ. Bourgogne Franche-Comté, Besançon, France
| | - Céline Demougeot
- 3 EA4267 PEPITE, FHU INCREASE, Univ. Bourgogne Franche-Comté, Besançon, France
| |
Collapse
|
43
|
Avolio A, Kim MO, Adji A, Gangoda S, Avadhanam B, Tan I, Butlin M. Cerebral Haemodynamics: Effects of Systemic Arterial Pulsatile Function and Hypertension. Curr Hypertens Rep 2018; 20:20. [PMID: 29556793 DOI: 10.1007/s11906-018-0822-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
PURPOSE OF REVIEW Concepts of pulsatile arterial haemodynamics, including relationships between oscillatory blood pressure and flow in systemic arteries, arterial stiffness and wave propagation phenomena have provided basic understanding of underlying haemodynamic mechanisms associated with elevated arterial blood pressure as a major factor of cardiovascular risk, particularly the deleterious effects of isolated systolic hypertension in the elderly. This topical review assesses the effects of pulsatility of blood pressure and flow in the systemic arteries on the brain. The review builds on the emerging notion of the "pulsating brain", taking into account the high throughput of blood flow in the cerebral circulation in the presence of mechanisms involved in ensuring efficient and regulated cerebral perfusion. RECENT FINDINGS Recent studies have provided evidence of the relevance of pulsatility and hypertension in the following areas: (i) pressure and flow pulsatility and regulation of cerebral blood flow, (ii) cerebral and systemic haemodynamics, hypertension and brain pathologies (cognitive impairment, dementia, Alzheimer's disease), (iii) stroke and cerebral small vessel disease, (iv) cerebral haemodynamics and noninvasive estimation of cerebral vascular impedance, (v) cerebral and systemic pulsatile haemodynamics and intracranial pressure, (iv) response of brain endothelial cells to cyclic mechanical stretch and increase in amyloid burden. Studies to date, producing increasing epidemiological, clinical and experimental evidence, suggest a potentially significant role of systemic haemodynamic pulsatility on structure and function of the brain.
Collapse
Affiliation(s)
- Alberto Avolio
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, 2109, Australia.
| | - Mi Ok Kim
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Audrey Adji
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, 2109, Australia.,St. Vincent's Clinic, Victor Chang Cardiac Research Institute, University of New South Wales, Sydney, Australia
| | - Sumudu Gangoda
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Bhargava Avadhanam
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Isabella Tan
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Mark Butlin
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| |
Collapse
|
44
|
Obata Y, Barodka V, Berkowitz DE, Gottschalk A, Hogue CW, Steppan J. Relationship Between the Ambulatory Arterial Stiffness Index and the Lower Limit of Cerebral Autoregulation During Cardiac Surgery. J Am Heart Assoc 2018; 7:JAHA.117.007816. [PMID: 29437601 PMCID: PMC5850197 DOI: 10.1161/jaha.117.007816] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Background Pulse pressure, the ambulatory arterial stiffness index (AASI), and the symmetric AASI are established predictors of adverse cardiovascular outcomes. However, little is known about their relationship to cerebral autoregulation. This study evaluated whether these markers of vascular properties relate to the lower limit of cerebral autoregulation (LLA). Methods and Results The LLA was determined during cardiac surgery with transcranial Doppler ultrasonography in 181 patients. All other variables were calculated from continuous intraoperative readings obtained before cardiopulmonary bypass. The LLA varied directly with the AASI (β=3.12 per 0.1 change in AASI, P<0.001) and to a lesser extent the symmetric AASI (β=2.02 per 0.1 change in symmetric AASI, P≤0.022), while peripheral pulse pressure was not significantly related (β=0.0, P>0.99). Logistic regression revealed that the likelihood of LLA being >65 mm Hg increased by 50% (95% confidence interval, 11%–102%, P=0.008) for every 0.1 increase in the AASI. The AASI was able to predict a LLA above certain thresholds (area under the curve receiver operating characteristic for AASI predicting an LLA >65 mm Hg: 0.60; 95% confidence interval, 0.51%–0.68%, P=0.043). Incorporating additional variables improved the model's predictive ability (area under the curve for AASI predicting a LLA >65 mm Hg: 0.75; 95% confidence interval, 0.68–0.82, P=0.036). Conclusions These data indicate that the LLA is related to the mechanical properties of the vasculature as represented by the AASI. The AASI can be used to predict LLA threshold levels during cardiac surgery. It is now possible to link elevations in the LLA with an increased AASI as determined from readily accessible intraoperative variables.
Collapse
Affiliation(s)
- Yurie Obata
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD
| | - Viachaslau Barodka
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD
| | - Dan E Berkowitz
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD.,Department of Biomedical Engineering, Johns Hopkins University Baltimore, MD
| | - Allan Gottschalk
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD
| | - Charles W Hogue
- Department of Anesthesiology, Northwestern University Feinberg, Chicago, IL
| | - Jochen Steppan
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD
| |
Collapse
|
45
|
Tripathi A, Obata Y, Ruzankin P, Askaryar N, Berkowitz DE, Steppan J, Barodka V. A Pulse Wave Velocity Based Method to Assess the Mean Arterial Blood Pressure Limits of Autoregulation in Peripheral Arteries. Front Physiol 2017; 8:855. [PMID: 29163200 PMCID: PMC5681752 DOI: 10.3389/fphys.2017.00855] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 10/13/2017] [Indexed: 01/28/2023] Open
Abstract
Background: Constant blood flow despite changes in blood pressure, a phenomenon called autoregulation, has been demonstrated for various organ systems. We hypothesized that by changing hydrostatic pressures in peripheral arteries, we can establish these limits of autoregulation in peripheral arteries based on local pulse wave velocity (PWV). Methods: Electrocardiogram and plethysmograph waveforms were recorded at the left and right index fingers in 18 healthy volunteers. Each subject changed their left arm position, keeping the right arm stationary. Pulse arrival times (PAT) at both fingers were measured and used to calculate PWV. We calculated ΔPAT (ΔPWV), the differences between the left and right PATs (PWVs), and compared them to the respective calculated blood pressure at the left index fingertip to derive the limits of autoregulation. Results: ΔPAT decreased and ΔPWV increased exponentially at low blood pressures in the fingertip up to a blood pressure of 70 mmHg, after which changes in ΔPAT and ΔPWV were minimal. The empirically chosen 20 mmHg window (75-95 mmHg) was confirmed to be within the autoregulatory limit (slope = 0.097, p = 0.56). ΔPAT and ΔPWV within a 20 mmHg moving window were not significantly different from the respective data points within the control 75-95 mmHg window when the pressure at the fingertip was between 56 and 110 mmHg for ΔPAT and between 57 and 112 mmHg for ΔPWV. Conclusions: Changes in hydrostatic pressure due to changes in arm position significantly affect peripheral arterial stiffness as assessed by ΔPAT and ΔPWV, allowing us to estimate peripheral autoregulation limits based on PWV.
Collapse
Affiliation(s)
- Ananya Tripathi
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Yurie Obata
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Pavel Ruzankin
- Sobolev Institute of Mathematics, Novosibirsk, Russia.,Department of Mathematics and Mechanics, Novosibirsk State University, Novosibirsk, Russia
| | - Narwan Askaryar
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Dan E Berkowitz
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Jochen Steppan
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Viachaslau Barodka
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| |
Collapse
|
46
|
Antunes A, Montgomery D, Addison P, Borg U. Correction of tissue oxygen saturations using arterial oxygen levels for cerebrovascular autoregulation analysis. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2017; 2017:4005-4008. [PMID: 29060775 DOI: 10.1109/embc.2017.8037734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Adequate perfusion of blood is fundamental to brain tissue viability, and failure to appropriately regulate cerebral blood flow is related to neurological damage. Cerebral tissue oxygenation is commonly used as a surrogate of cerebral blood flow for non-invasive measures of autoregulation, but may only be valid during periods of constant oxygen delivery. We present a new algorithm to correct for supply oxygen-induced variations in cerebral tissue oxygenation, and we validate it by measuring the improved correlation of the corrected tissue oxygenation with blood flow. The algorithm corrects tissue oxygenation by calculating its linear dependence with arterial oxygen saturation below a baseline level. A porcine model (N=8) of hypoxia is used to test the algorithm and compare the tissue oxygen correction with a blood flow reference signal. The correction provides significant improvement in the correlation between flow and tissue oxygenation (Wilcoxon signed rank, p<;0.01), and for the root mean square distance between the corrected hypoxic periods and the rSO2-flow regression line (Wilcoxon signed rank, p<;0.01). This method allows the correction of tissue oxygenation levels used in the non-invasive monitoring of autoregulation.
Collapse
|
47
|
Wu S, Hao G, Zhang S, Jiang D, Wuren T, Luo J. Cerebral vasoconstriction reactions and plasma levels of ETBR, ET-1, and eNOS in patients with chronic high altitude disease. Mol Med Rep 2016; 14:2497-502. [PMID: 27485004 PMCID: PMC4991730 DOI: 10.3892/mmr.2016.5555] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 07/27/2016] [Indexed: 12/14/2022] Open
Abstract
The aim of the present study was to examine cerebral vasoconstriction in patients with chronic high altitude disease [cerebrovascular reactivity (CVR)], and to evaluate differences in alterations of brain vascular contractile reactivity of chronic mountain sickness (CMS) patients and healthy controls. Alterations of endothelin (ET) and its receptor, as well as endothelial nitric oxide synthase (eNOS) levels in the plasma were examined to determine the cerebral reservation capacities in CMS patients. Transcranial Doppler ultrasound and carbon dioxide analysis methods were used to detect the CVR variances. At the same time, enzyme-linked immunosorbent assay approaches were utilized to detect the ET and ET B receptor and the eNOS levels in serum of the CMS patients and healthy controls. CVR and CVRI levels in CMS patients were lower than those of the healthy control subjects and the difference was statistically significant (P<0.05). By contrast, eNOS and ET-1 levels were not statistically significant for CMS and healthy controls (P>0.05). However, the ET receptor concentration level was higher in CMS than the healthy controls. Thus, ET-1 may not be a direct etiological variation but may play compensatory roles in CMS patients. The results of the study may provide scientific clues for the prevention and treatment of CMS with higher blood coagulation states of cerebral infarction in patients with chronic high altitude disease.
Collapse
Affiliation(s)
- Shizheng Wu
- Department of Neurology, Qinghai Provincial People's Hospital, Xining, Qinghai 810007, P.R. China
| | - Guisheng Hao
- Department of Neurology, Qinghai Provincial People's Hospital, Xining, Qinghai 810007, P.R. China
| | - Shukun Zhang
- Department of Pathology, Qinghai Provincial People's Hospital, Xining, Qinghai 810007, P.R. China
| | - Dongmei Jiang
- Research Center for High Altitude Medicine, Qinghai University, Xining, Qinghai 810001, P.R. China
| | - Tana Wuren
- Research Center for High Altitude Medicine, Qinghai University, Xining, Qinghai 810001, P.R. China
| | - Junming Luo
- Department of Pathology, Qinghai Provincial People's Hospital, Xining, Qinghai 810007, P.R. China
| |
Collapse
|
48
|
Hardigan T, Yasir A, Abdelsaid M, Coucha M, El-Shaffey S, Li W, Johnson MH, Ergul A. Linagliptin treatment improves cerebrovascular function and remodeling and restores reduced cerebral perfusion in Type 2 diabetes. Am J Physiol Regul Integr Comp Physiol 2016; 311:R466-77. [PMID: 27357799 DOI: 10.1152/ajpregu.00057.2016] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Accepted: 06/24/2016] [Indexed: 12/20/2022]
Abstract
The antihyperglycemic agent linagliptin, a dipeptidyl peptidase-4 (DPP-IV) inhibitor, has been shown to reduce inflammation and improve endothelial cell function. In this study, we hypothesized that DPP-IV inhibition with linagliptin would improve impaired cerebral perfusion in diabetic rats, as well as improve insulin-induced cerebrovascular relaxation and reverse pathological cerebrovascular remodeling. We further postulated that these changes would lead to a subsequent improvement of cognitive function. Male Type-2 diabetic and nondiabetic Goto-Kakizaki rats were treated with linagliptin for 4 wk, and blood glucose and DPP-IV plasma levels were assessed. Cerebral perfusion was assessed after treatment using laser-Doppler imaging, and dose response to insulin (10(-13) M-10(-6) M) in middle cerebral arteries was tested on a pressurized arteriograph. The impact of DPP-IV inhibition on diabetic cerebrovascular remodeling was assessed over a physiologically relevant pressure range, and changes in short-term hippocampus-dependent learning were observed using a novel object recognition test. Linagliptin lowered DPP-IV activity but did not change blood glucose or insulin levels in diabetes. Insulin-mediated vascular relaxation and cerebral perfusion were improved in the diabetic rats with linagliptin treatment. Indices of diabetic vascular remodeling, such as increased cross-sectional area, media thickness, and wall-to-lumen ratio, were also ameliorated; however, improvements in short-term hippocampal-dependent learning were not observed. The present study provides evidence that linagliptin treatment improves cerebrovascular dysfunction and remodeling in a Type 2 model of diabetes independent of glycemic control. This has important implications in diabetic patients who are predisposed to the development of cerebrovascular complications, such as stroke and cognitive impairment.
Collapse
Affiliation(s)
- Trevor Hardigan
- Department of Physiology, Medical College of Georgia, Augusta, Georgia; and
| | - Abdul Yasir
- Department of Physiology, Medical College of Georgia, Augusta, Georgia; and
| | - Mohammed Abdelsaid
- Charlie Norwood Veterans Administration Medical Center, Augusta, Georgia; Department of Physiology, Medical College of Georgia, Augusta, Georgia; and
| | - Maha Coucha
- Charlie Norwood Veterans Administration Medical Center, Augusta, Georgia; Department of Physiology, Medical College of Georgia, Augusta, Georgia; and
| | - Sally El-Shaffey
- Department of Physiology, Medical College of Georgia, Augusta, Georgia; and
| | - Weiguo Li
- Charlie Norwood Veterans Administration Medical Center, Augusta, Georgia; Department of Physiology, Medical College of Georgia, Augusta, Georgia; and
| | - Maribeth H Johnson
- Department of Biostatistics, The Graduate School at Augusta University, Augusta, Georgia
| | - Adviye Ergul
- Charlie Norwood Veterans Administration Medical Center, Augusta, Georgia; Department of Physiology, Medical College of Georgia, Augusta, Georgia; and
| |
Collapse
|
49
|
Donnelly J, Budohoski KP, Smielewski P, Czosnyka M. Regulation of the cerebral circulation: bedside assessment and clinical implications. Crit Care 2016; 20:129. [PMID: 27145751 PMCID: PMC4857376 DOI: 10.1186/s13054-016-1293-6] [Citation(s) in RCA: 122] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Regulation of the cerebral circulation relies on the complex interplay between cardiovascular, respiratory, and neural physiology. In health, these physiologic systems act to maintain an adequate cerebral blood flow (CBF) through modulation of hydrodynamic parameters; the resistance of cerebral vessels, and the arterial, intracranial, and venous pressures. In critical illness, however, one or more of these parameters can be compromised, raising the possibility of disturbed CBF regulation and its pathophysiologic sequelae. Rigorous assessment of the cerebral circulation requires not only measuring CBF and its hydrodynamic determinants but also assessing the stability of CBF in response to changes in arterial pressure (cerebral autoregulation), the reactivity of CBF to a vasodilator (carbon dioxide reactivity, for example), and the dynamic regulation of arterial pressure (baroreceptor sensitivity). Ideally, cerebral circulation monitors in critical care should be continuous, physically robust, allow for both regional and global CBF assessment, and be conducive to application at the bedside. Regulation of the cerebral circulation is impaired not only in primary neurologic conditions that affect the vasculature such as subarachnoid haemorrhage and stroke, but also in conditions that affect the regulation of intracranial pressure (such as traumatic brain injury and hydrocephalus) or arterial blood pressure (sepsis or cardiac dysfunction). Importantly, this impairment is often associated with poor patient outcome. At present, assessment of the cerebral circulation is primarily used as a research tool to elucidate pathophysiology or prognosis. However, when combined with other physiologic signals and online analytical techniques, cerebral circulation monitoring has the appealing potential to not only prognosticate patients, but also direct critical care management.
Collapse
Affiliation(s)
- Joseph Donnelly
- />Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, Cambridge Biomedical Campus, University of Cambridge, Hills Road, Cambridge, CB2 0QQ UK
| | - Karol P. Budohoski
- />Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, Cambridge Biomedical Campus, University of Cambridge, Hills Road, Cambridge, CB2 0QQ UK
| | - Peter Smielewski
- />Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, Cambridge Biomedical Campus, University of Cambridge, Hills Road, Cambridge, CB2 0QQ UK
| | - Marek Czosnyka
- />Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, Cambridge Biomedical Campus, University of Cambridge, Hills Road, Cambridge, CB2 0QQ UK
- />Institute of Electronic Systems, Warsaw University of Technology, ul. Nowowiejska 15/19, 00-665 Warsaw, Poland
| |
Collapse
|
50
|
Montagne A, Nation DA, Pa J, Sweeney MD, Toga AW, Zlokovic BV. Brain imaging of neurovascular dysfunction in Alzheimer's disease. Acta Neuropathol 2016; 131:687-707. [PMID: 27038189 PMCID: PMC5283382 DOI: 10.1007/s00401-016-1570-0] [Citation(s) in RCA: 143] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 03/21/2016] [Accepted: 03/23/2016] [Indexed: 11/29/2022]
Abstract
Neurovascular dysfunction, including blood-brain barrier (BBB) breakdown and cerebral blood flow (CBF) dysregulation and reduction, are increasingly recognized to contribute to Alzheimer's disease (AD). The spatial and temporal relationships between different pathophysiological events during preclinical stages of AD, including cerebrovascular dysfunction and pathology, amyloid and tau pathology, and brain structural and functional changes remain, however, still unclear. Recent advances in neuroimaging techniques, i.e., magnetic resonance imaging (MRI) and positron emission tomography (PET), offer new possibilities to understand how the human brain works in health and disease. This includes methods to detect subtle regional changes in the cerebrovascular system integrity. Here, we focus on the neurovascular imaging techniques to evaluate regional BBB permeability (dynamic contrast-enhanced MRI), regional CBF changes (arterial spin labeling- and functional-MRI), vascular pathology (structural MRI), and cerebral metabolism (PET) in the living human brain, and examine how they can inform about neurovascular dysfunction and vascular pathophysiology in dementia and AD. Altogether, these neuroimaging approaches will continue to elucidate the spatio-temporal progression of vascular and neurodegenerative processes in dementia and AD and how they relate to each other.
Collapse
Affiliation(s)
- Axel Montagne
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, USA
| | - Daniel A Nation
- Department of Psychology, University of Southern California, Los Angeles, CA, 90089, USA
| | - Judy Pa
- Department of Neurology, Institute for Neuroimaging and Informatics, University of Southern California, Los Angeles, CA, 90089, USA
| | - Melanie D Sweeney
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, USA
| | - Arthur W Toga
- Department of Neurology, Institute for Neuroimaging and Informatics, University of Southern California, Los Angeles, CA, 90089, USA
| | - Berislav V Zlokovic
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, USA.
| |
Collapse
|