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Sensor-Assisted Analysis of Autonomic and Cerebrovascular Dysregulation following Concussion in an Individual with a History of Ten Concussions: A Case Study.

INTRODUCTION: Concussion is known to cause transient autonomic and cerebrovascular dysregulation that generally recovers; however, few studi … is injury and on days 1-5, 10, and 14 post-injury. Symptom reporting, heart rate variability (HRV), neurovascular coupling (NVC), and dynamic cerebral autoregulation (dCA) assessments were completed using numerous biomedical devices (i.e., transcranial Doppler ultrasound, 3-lead electrocardiography, finger photoplethysmography). RESULTS: Total symptom and symptom sever …

Disordered APP metabolism and neurovasculature in trauma and aging: Combined risks for chronic neurodegenerative disorders.

Traumatic brain injury (TBI), advanced age, and cerebral vascular disease are factors conferring increased risk for late onset Alzheimer's disease (AD). These conditions are also related pathologically through multiple interacting mechanisms. The hallmark pathology of AD consists of pathological aggregates of amyloid-β (Aβ) peptides and tau proteins. These molecules are also involved in neuropathology of several other chronic neurodegenerative diseases, and are under intense investigation in the aftermath of TBI as potential contributors to the risk for developing AD and chronic traumatic ence

A role for endothelial NMDA receptors in the pathophysiology of schizophrenia.

Numerous genetic and postmortem studies link N-methyl-d-aspartate receptor (NMDAR) dysfunction with schizophrenia, forming the basis of the … thelial NMDAR dysfunction. In particular, we emphasize that endothelial NMDARs are key mediators of neurovascular coupling, where increased neuronal activity leads to increased blood flow. Based on the broad conclusions that hypoperfusion is a neuroanatomical finding in schizophrenia, we discuss potential mechanisms by which endothelial NMDARs contribute to this disorde …

Mitochondrial Dysfunction and Diabetic Retinopathy: Research Progress from Pathogenic Mechanisms to Therapeutic Targets.

Diabetic retinopathy (DR) is one of the most common microvascular complications of diabetes mellitus (DM) and remains a major cause of visual impairment and blindness in adults. Accumulating evidence indicates that DR is not merely a microvascular disorder, but a complex neurovascular disease driven by long-standing hyperglycemia, metabolic dysregulation, oxidative stress, chronic inflammation, neurodegeneration, and impaired neurovascular coupling. Mitochondria are central regulators of cellular energy metabolism and redox homeostasis, and mitochondrial dysfunction is increasingly recognized …

Coupling between visual evoked cerebral blood flow velocity responses and visual evoked potentials in migraneurs.

Neurovascular coupling may be altered in migraneurs. Therefore, visual evoked potentials (VEP) and visually evoked cerebral blood flow velocity responses (VEFR) were simultaneously recorded in 30 healthy controls and 30 migraneurs interictally using a checkerboard stimulus with visual contrasts of 1%, 10% and 100%. The VEFR were measured in the posterior cerebral artery using transcranial Doppler and VEP were recorded from occipital leads. We found an increase in VEFR and VEP in both the healthy and migraneur groups (P < 0.01). VEFR were significantly higher in migraneurs (P < 0.01), while VEP…

Region-Specific Neurovascular Decoupling Associated With Cognitive Decline in Parkinson's Disease.

Background: Cognitive deficits are prominent non-motor symptoms in Parkinson's disease (PD) and have been shown to involve the neurovascular … rment (MCI) and normal cognition (NC) as well as matched healthy controls (HCs). Imaging metrics of neurovascular coupling (global and regional CBF-ReHo correlation coefficients and CBF-ReHo ratios) were compared among the groups. Results: Neurovascular coupling was impaired in patients with PD-MCI with a decreased global CBF-ReHo correlation coefficient relative to HC …

Oxygen therapy improves cerebral oxygen delivery and neurovascular function in hypoxaemic chronic obstructive pulmonary disease patients.

NEW FINDINGS: What is the central question of this study? How does oxygen therapy influence cerebral blood flow, cerebral oxygen delivery an … T: We investigated the role of hypoxaemia in cerebral blood flow (CBF), oxygen delivery (CDO2 ) and neurovascular coupling (coupling of CBF to neural activity; NVC) in hypoxaemic chronic obstructive pulmonary disease (COPD) patients (n = 14). Resting CBF (duplex ultrasound), peripheral oxyhaemoglobin saturation (SpO2; pulse-oximetry) and NVC (transcranial Doppler) were …

Altered coupling of cerebral blood flow and functional connectivity strength in visual and higher order cognitive cortices in primary open angle glaucoma.

Primary open-angle glaucoma (POAG) has been suggested to be a neurodegenerative disease associated with altered cerebral vascular hemodynamics and widespread disruption of neuronal activity within the visual, working memory, attention and executive networks. We hypothesized that disturbed neurovascular coupling in visual and higher order cognitive cortices exists in POAG patients and correlates with glaucoma stage and visual field defects. Through multimodal magnetic resonance imaging, we evaluated the cerebral blood flow (CBF)-functional connectivity strength (FCS) correlations of the whole g…

Intrauterine inflammation and postnatal intravenous dopamine alter the neurovascular unit in preterm newborn lambs.

BACKGROUND: Intrauterine inflammation is considered a major cause of brain injury in preterm infants, leading to long-term neurodevelopmental deficits. A potential contributor to this brain injury is dysregulation of neurovascular coupling. We have shown that intrauterine inflammation induced by intra-amniotic lipopolysaccharide (LPS) in preterm lambs, and postnatal dopamine administration, disrupts neurovascular coupling and the functional cerebral haemodynamic responses, potentially leading to impaired brain development. In this study, we aimed to characterise the structural changes of the n…

Quantitative analysis of hemodynamic and metabolic changes in subcortical vascular dementia using simultaneous near-infrared spectroscopy and fMRI measurements.

Subcortical vascular dementia (SVD) is a form of vascular dementia from small vessel disease with white matter lesions and lacunes. We hypothesized that hemodynamic and metabolic changes in the cortex during a simple motor task may reflect the impaired neurovascular coupling in SVD. We used fMRI and near-infrared spectroscopy (NIRS) simultaneously, which together provided multiple hemodynamic responses as well as a robust estimation of the cerebral metabolic rate of oxygen (CMRO(2)). During the task periods, the oxy-hemoglobin, total-hemoglobin, blood oxygenation level-dependent (BOLD) respons…

Neurovascular dysregulation in the thalamic-temporo-occipital axis is linked to emotional blunting and visual imagery deficits in depression.

BACKGROUND: Depression is characterized by clinical features such as emotional blunting and reduced vividness of visual mental imagery. Impaired neurovascular coupling (NVC) may represent a shared pathophysiological mechanism linking these symptoms. However, this potential connection remains unexplored. METHODS: A cohort of 117 participants (59 depressed patients, 58 healthy controls) completed the PHQ-9, HAMD-17, Vividness of Visual Imagery Questionnaire (VVIQ), and Emotional Contagion Scale (ECS), and underwent rs-fMRI, ASL, and dynamic cerebral autoregulation (dCA). Neurovascular regulatio…

Исследование нейро-сосудистой реактивности на исследовании FMRI во время визуальной активации у людей с множественным склерозом с использованием ЭЭГ и гиперкапния.

У людей с множественным склерозом (MS) наблюдается разная модель активации уровня кислорода в крови (BOLD) в ходе исследований функционального магнитного резонансного изображения (FMRI) по сравнению со здоровым контролем (HC). ЦЕЛЬ: Цель настоящего исследования заключается в определении того, обусловлены ли наблюдаемые различия в активации БЛД между людьми, имеющими MS (PwMS) и HC, различиями в нейроваскулярном сцеплении, церебральном потоке крови (CBF) или фактической нейрональной активности.МЕТОДЫ: Мы изучили нейронную активацию в PwMS (n = 11) и совпадающих по возрасту и полу участников HC

Совпадение в аннотации оригинала
BACKGROUND: People with multiple sclerosis (MS) exhibit a different pattern of blood oxygenation level-dependent (BOLD) activation on functi … in BOLD activation between people with MS (pwMS) and HC participants are due to the differences of neurovascular coupling, cerebral blood flow (CBF) or actual neuronal activity. METHODS: We investigated the neuronal activation in pwMS (n = 11) and age- and sex-matched HC participants (n = 15) using simultaneous electroencephalogram (EEG) and fMRI measures during a vis …

Nimodipine accelerates the restoration of functional hyperemia during spreading oligemia.

Spreading depolarization (SD) is assumed to be the pathophysiological correlate of migraine aura, leading to spreading depression of activity and a long-lasting vasoconstriction known as spreading oligemia. Furthermore, cerebrovascular reactivity is reversibly impaired after SD. Here, we explored the progressive restoration of impaired neurovascular coupling to somatosensory activation during spreading oligemia. Also, we evaluated whether nimodipine treatment accelerated the recovery of impaired neurovascular coupling after SD. Male, 4-9-month-old C57BL/6 mice (n = 11) were anesthetized with i…

Modeling ischemic stroke in a triculture neurovascular unit on-a-chip.

BACKGROUND: In ischemic stroke, the function of the cerebral vasculature is impaired. This vascular structure is formed by the so-called neurovascular unit (NVU). A better understanding of the mechanisms involved in NVU dysfunction and recovery may lead to new insights for the development of highly sought therapeutic approaches. To date, there remains an unmet need for complex human in vitro models of the NVU to study ischemic events seen in the human brain. METHODS: We here describe the development of a human NVU on-a-chip model using a platform that allows culture of 40 chips in parallel. T

Cerebral microvascular dysfunction and neurodegeneration in dementia.

Maintaining normal learning and memory functions requires a high degree of coordination between neural and vascular cells. Basic and clinical studies have shown that brain microvasculature dysfunction activates inflammatory cells in the brain, leading to progressive neuronal loss and eventually dementia. This review focuses on recent studies aimed at identifying the molecular events that link cerebral microvascular dysfunction to neurodegeneration, including oxidative/nitrosative stress, cellular metabolic dysfunction, inflammatory signalling and abnormal synaptic plasticity. A better understa

Stronger influence of systemic than local hemodynamic-vascular factors on resting-state BOLD functional connectivity.

Correlated fluctuations in the blood oxygenation level dependent (BOLD) signal of resting-state functional MRI (i.e., BOLD-functional connectivity, BOLD-FC) reflect a spectrum of neuronal and non-neuronal processes. In particular, there are multiple hemodynamic-vascular influences on BOLD-FC on both systemic (e.g., perfusion delay) and local levels (e.g., neurovascular coupling). While the influence of individual factors has been studied extensively, combined and comparative studies of systemic and local hemodynamic-vascular factors on BOLD-FC are scarce, notably in humans. We employed a multi…

Potential crosstalk between sonic hedgehog-WNT signaling and neurovascular molecules: Implications for blood-brain barrier integrity in autism spectrum disorder.

Autism Spectrum Disorder (ASD) is a neurodevelopmental disease originating from combined genetic and environmental factors. Post-mortem human studies and some animal ASD models have shown brain neuroinflammation, oxidative stress, and changes in blood-brain barrier (BBB) integrity. However, the signaling pathways leading to these inflammatory findings and vascular alterations are currently unclear. The BBB plays a critical role in controlling brain homeostasis and immune response. Its dysfunction can result from developmental genetic abnormalities or neuroinflammatory processes. In this review

Nitric oxide as a mechanistic link between metabolic dysfunction and cognitive decline in type 2 diabetes.

Type 2 diabetes mellitus (T2DM) is increasingly recognised as a driver of cerebrovascular dysfunction and cognitive decline, yet the molecul … d flow regulation and maladaptive remodelling of the cerebrovascular network, ultimately disrupting neurovascular coupling (NVC) and reducing regional cerebral perfusion. Together, impaired perfusion and disrupted NVC result in a sustained mismatch between energy supply and neuronal demand, particularly in metabolically vulnerable regions such as the hippocampus, ultima …

Associations of retinal neurovascular dysfunction with inner retinal layer thickness in non-proliferative diabetic retinopathy.

PURPOSE: Neurovascular coupling impairment and inner retinal layer thinning are early detectable retinal changes in diabetes, and both worsen during progression of diabetic retinopathy (DR). However, direct interactions between these features have not been investigated so far. Therefore, we aimed to analyze associations between the retinal functional hyperemic response to light stimulation and the thickness of individual neuroretinal layers in eyes with early non-proliferative DR. METHODS: Thirty patients with type 1 diabetes featuring mild (n = 15) or moderate (n = 15) non-proliferative DR a…

Functional laser Doppler flowmetry of the optic nerve: physiological aspects and clinical applications.

The present paper reviews the methodology and clinical results of recording, by laser Doppler flowmetry, the hemodynamic response of the optic nerve head elicited by visual stimulation. The basic mechanism underlying this novel technique (which is called here functional laser Doppler flowmetry (FLDF)) is the coupling between visually evoked neural activity and vascular activity within the neural tissue of the optic nerve (neurovascular coupling). The blood flow responses elicited by various visual stimuli (luminance and chromatic flicker, focal and pattern stimulation) have been characterized …