scholarly journals PIP2 corrects cerebral blood flow deficits in small vessel disease by rescuing capillary Kir2.1 activity

2021 ◽  
Vol 118 (17) ◽  
pp. e2025998118
Author(s):  
Fabrice Dabertrand ◽  
Osama F. Harraz ◽  
Masayo Koide ◽  
Thomas A. Longden ◽  
Amanda C. Rosehart ◽  
...  
Keyword(s):  
Blood Flow ◽  
Small Vessel Disease ◽  
Brain Regions ◽  
Electrical Signal ◽  
Small Vessel ◽  
Functional Hyperemia ◽  
Channel Activity ◽  
Systemic Injection ◽  
Kir2.1 Channel ◽  
Cerebral Small Vessel Diseases

Cerebral small vessel diseases (SVDs) are a central link between stroke and dementia—two comorbidities without specific treatments. Despite the emerging consensus that SVDs are initiated in the endothelium, the early mechanisms remain largely unknown. Deficits in on-demand delivery of blood to active brain regions (functional hyperemia) are early manifestations of the underlying pathogenesis. The capillary endothelial cell strong inward-rectifier K+ channel Kir2.1, which senses neuronal activity and initiates a propagating electrical signal that dilates upstream arterioles, is a cornerstone of functional hyperemia. Here, using a genetic SVD mouse model, we show that impaired functional hyperemia is caused by diminished Kir2.1 channel activity. We link Kir2.1 deactivation to depletion of phosphatidylinositol 4,5-bisphosphate (PIP2), a membrane phospholipid essential for Kir2.1 activity. Systemic injection of soluble PIP2 rapidly restored functional hyperemia in SVD mice, suggesting a possible strategy for rescuing functional hyperemia in brain disorders in which blood flow is disturbed.

scholarly journals Prostaglandin E2 Dilates Intracerebral Arterioles When Applied to Capillaries: Implications for Small Vessel Diseases

2021 ◽  
Vol 13 ◽  
Author(s):  
Amanda C. Rosehart ◽  
Thomas A. Longden ◽  
Nick Weir ◽  
Jackson T. Fontaine ◽  
Anne Joutel ◽  
...  
Keyword(s):  
Blood Flow ◽  
Laser Scanning ◽  
Small Vessel Disease ◽  
Ex Vivo ◽  
Neurovascular Coupling ◽  
Laser Scanning Microscopy ◽  
Small Vessel ◽  
Prostaglandin E ◽  
Functional Hyperemia ◽  
Flow Measurements

Prostaglandin E2 (PGE2) has been widely proposed to mediate neurovascular coupling by dilating brain parenchymal arterioles through activation of prostanoid EP4 receptors. However, our previous report that direct application of PGE2 induces an EP1-mediated constriction strongly argues against its direct action on arterioles during neurovascular coupling, the mechanisms sustaining functional hyperemia. Recent advances have highlighted the role of capillaries in sensing neuronal activity and propagating vasodilatory signals to the upstream penetrating parenchymal arteriole. Here, we examined the effect of capillary stimulation with PGE2 on upstream arteriolar diameter using an ex vivo capillary-parenchymal arteriole preparation and in vivo cerebral blood flow measurements with two-photon laser-scanning microscopy. We found that PGE2 caused upstream arteriolar dilation when applied onto capillaries with an EC50 of 70 nM. The response was inhibited by EP1 receptor antagonist and was greatly reduced, but not abolished, by blocking the strong inward-rectifier K+ channel. We further observed a blunted dilatory response to capillary stimulation with PGE2 in a genetic mouse model of cerebral small vessel disease with impaired functional hyperemia. This evidence casts previous findings in a different light, indicating that capillaries are the locus of PGE2 action to induce upstream arteriolar dilation in the control of brain blood flow, thereby providing a paradigm-shifting view that nonetheless remains coherent with the broad contours of a substantial body of existing literature.

scholarly journals Cerebral Small Vessel Disease

2020 ◽  
Vol 21 (24) ◽  
pp. 9729
Author(s):  
Jakub Litak ◽  
Marek Mazurek ◽  
Bartłomiej Kulesza ◽  
Paweł Szmygin ◽  
Joanna Litak ◽  
...  
Keyword(s):  
Small Vessel Disease ◽  
Current Knowledge ◽  
Cerebral Small Vessel Disease ◽  
Cerebral Vessels ◽  
Small Vessel ◽  
Epithelial Layer ◽  
Small Arteries ◽  
Vessel Disease ◽  
The Impact ◽  
Cerebral Small Vessel Diseases

Cerebral small vessel disease (CSVD) represents a cluster of various vascular disorders with different pathological backgrounds. The advanced vasculature net of cerebral vessels, including small arteries, capillaries, arterioles and venules, is usually affected. Processes of oxidation underlie the pathology of CSVD, promoting the degenerative status of the epithelial layer. There are several classifications of cerebral small vessel diseases; some of them include diseases such as Binswanger’s disease, leukoaraiosis, cerebral microbleeds (CMBs) and lacunar strokes. This paper presents the characteristics of CSVD and the impact of the current knowledge of this topic on the diagnosis and treatment of patients.

Brain MRI in Monogenic Cerebral Small Vessel Diseases: A Practical Handbook

2021 ◽  
Vol 21 ◽  
Author(s):  
Leonardo Ulivi ◽  
Mirco Cosottini ◽  
Gianmichele Migaleddu ◽  
Giovanni Orlandi ◽  
Nicola Giannini ◽  
...  
Keyword(s):  
Genetic Testing ◽  
Next Generation Sequencing ◽  
Small Vessel Disease ◽  
Brain Mri ◽  
Cerebral Small Vessel Disease ◽  
Small Vessel ◽  
Next Generation ◽  
Vessel Disease ◽  
Generation Sequencing ◽  
Cerebral Small Vessel Diseases

: Monogenic cerebral small vessel diseases are a topic of growing interest, as several genes responsible have been recently described and new sequencing techniques such as Next generation sequencing are available. Brain imaging is a key exam in these diseases. First, since it is often the first exam performed, an MRI is key in selecting patients for genetic testing and for interpreting Next generation sequencing reports. In addition, neuroimaging can be helpful in describing the underlying pathological mechanisms involved in cerebral small vessel disease. With this review, we aim to provide Neurologists and Stroke physicians with an up-to date overview of the current neuroimaging knowledge on monogenic small vessel diseases.

scholarly journals P4-078: REPRESENTATION OF BLOOD FLOW IN PERFORATING BASAL GANGLIA ARTERIES OF PATIENTS WITH CEREBRAL SMALL VESSEL DISEASE (CSVD) AT 7 TESLA MRI

2019 ◽  
Vol 15 ◽  
pp. P1304-P1304
Author(s):  
Valentina Perosa ◽  
Emrah Düzel ◽  
Tine Arts ◽  
Stefanie Schreiber ◽  
Anne Assmann ◽  
...  
Keyword(s):  
Blood Flow ◽  
Basal Ganglia ◽  
Small Vessel Disease ◽  
Cerebral Small Vessel Disease ◽  
Small Vessel ◽  
7 Tesla ◽  
Vessel Disease ◽  
7 Tesla Mri

scholarly journals Microstructural Predictors of Cognitive Impairment in Cerebral Small Vessel Disease and the Conditions of Their Formation

Diagnostics ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 720
Author(s):  
Larisa A. Dobrynina ◽  
Zukhra Sh. Gadzhieva ◽  
Kamila V. Shamtieva ◽  
Elena I. Kremneva ◽  
Bulat M. Akhmetzyanov ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cognitive Impairment ◽  
White Matter ◽  
Diffusion Tensor ◽  
Small Vessel Disease ◽  
Cerebral Small Vessel Disease ◽  
Small Vessel ◽  
Venous Blood Flow ◽  
Csf Flow ◽  
Vessel Disease

Introduction: Cerebral small vessel disease (CSVD) is the leading cause of vascular and mixed degenerative cognitive impairment (CI). The variability in the rate of progression of CSVD justifies the search for sensitive predictors of CI. Materials: A total of 74 patients (48 women, average age 60.6 ± 6.9 years) with CSVD and CI of varying severity were examined using 3T MRI. The results of diffusion tensor imaging with a region of interest (ROI) analysis were used to construct a predictive model of CI using binary logistic regression, while phase-contrast magnetic resonance imaging and voxel-based morphometry were used to clarify the conditions for the formation of CI predictors. Results: According to the constructed model, the predictors of CI are axial diffusivity (AD) of the posterior frontal periventricular normal-appearing white matter (pvNAWM), right middle cingulum bundle (CB), and mid-posterior corpus callosum (CC). These predictors showed a significant correlation with the volume of white matter hyperintensity; arterial and venous blood flow, pulsatility index, and aqueduct cerebrospinal fluid (CSF) flow; and surface area of the aqueduct, volume of the lateral ventricles and CSF, and gray matter volume. Conclusion: Disturbances in the AD of pvNAWM, CB, and CC, associated with axonal damage, are a predominant factor in the development of CI in CSVD. The relationship between AD predictors and both blood flow and CSF flow indicates a disturbance in their relationship, while their location near the floor of the lateral ventricle and their link with indicators of internal atrophy, CSF volume, and aqueduct CSF flow suggest the importance of transependymal CSF transudation when these regions are damaged.

scholarly journals Cerebral angiogenesis ameliorates pathological disorders in Nemo-deficient mice with small-vessel disease

2020 ◽  
pp. 0271678X2091052
Author(s):  
Yun Jiang ◽  
Kristin Müller ◽  
Mahtab A. Khan ◽  
Julian C. Assmann ◽  
Josephine Lampe ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Endothelial Cells ◽  
Small Vessel Disease ◽  
Small Vessel ◽  
Incontinentia Pigmenti ◽  
Brain Endothelial Cells ◽  
Functional Deficits ◽  
Intussusceptive Angiogenesis ◽  
Inactivating Mutations ◽  
Cerebral Small Vessel Diseases

Cerebral small-vessel diseases (SVDs) often follow a progressive course. Little is known about the function of angiogenesis, which potentially induces regression of SVDs. Here, we investigated angiogenesis in a mouse model of incontinentia pigmenti (IP), a genetic disease comprising features of SVD. IP is caused by inactivating mutations of Nemo, the essential component of NF-κB signaling. When deleting Nemo in the majority of brain endothelial cells ( NemobeKO mice), the transcriptional profile of vessels indicated cell proliferation. Brain endothelial cells expressed Ki67 and showed signs of DNA synthesis. In addition to cell proliferation, we observed sprouting and intussusceptive angiogenesis in NemobeKO mice. Angiogenesis occurred in all segments of the vasculature and in proximity to vessel rarefaction and tissue hypoxia. Apparently, NEMO was required for productive angiogenesis because endothelial cells that had escaped Nemo inactivation showed a higher proliferation rate than Nemo-deficient cells. Therefore, newborn endothelial cells were particularly vulnerable to ongoing recombination. When we interfered with productive angiogenesis by inducing ongoing ablation of Nemo, mice did not recover from IP manifestations but rather showed severe functional deficits. In summary, the data demonstrate that angiogenesis is present in this model of SVD and suggest that it may counterbalance the loss of vessels.

Adverse effects of pre-existing cerebral small vessel disease on cognitive improvement after carotid endarterectomy

2019 ◽  
Vol 15 (6) ◽  
pp. 657-665 ◽  
Author(s):  
Jun Yoshida ◽  
Fumio Yamashita ◽  
Makoto Sasaki ◽  
Kunihiro Yoshioka ◽  
Shunrou Fujiwara ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
White Matter ◽  
Carotid Endarterectomy ◽  
White Matter Hyperintensities ◽  
Small Vessel Disease ◽  
Cerebral Small Vessel Disease ◽  
Small Vessel ◽  
Cognitive Improvement ◽  
Vessel Disease

Background Although patients with improved cognition after carotid endarterectomy usually exhibit postoperative restoration of cerebral blood flow, less than half of patients with such cerebral blood flow change have postoperatively improved cognition. Cerebral small vessel disease on magnetic resonance imaging is associated with irreversible cognitive impairment. Aims The purpose of the present prospective study was to determine whether pre-existing cerebral small vessel disease affects cognitive improvement after carotid endarterectomy. Methods Brain MR imaging was performed preoperatively, and the number or grade of each cerebral small vessel disease was determined in 80 patients undergoing carotid endarterectomy for ipsilateral internal carotid artery stenosis (≥70%). The volume of white matter hyperintensities relative to the intracranial volume was also calculated. Brain perfusion single-photon emission computed tomography and neuropsychological testing were performed preoperatively and two months postoperatively. Based on these data, a postoperative increase in cerebral blood flow and postoperative improved cognition, respectively, were determined. Results Logistic regression analysis using the sequential backward elimination approach revealed that a postoperative increase in cerebral blood flow (95% confidence interval [CI], 10.74–3730.00; P = 0.0004) and the relative volume of white matter hyperintensities (95% CI, 0.01–0.63; P = 0.0314) were significantly associated with postoperative improved cognition. Although eight of nine patients with postoperative improved cognition exhibited both a relative volume of white matter hyperintensities <0.65% and a postoperative increase in cerebral blood flow, none of patients with a relative volume of white matter hyperintensities ≥0.65% had postoperative improved cognition regardless of any postoperative change in cerebral blood flow. Conclusion Pre-existing cerebral white matter hyperintensities on magnetic resonance imaging adversely affect cognitive improvement after carotid endarterectomy.

Statistical Parametric Analysis of Cerebral Blood Flow in Vascular Dementia with Small-Vessel Disease Using 99mTc-HMPAO SPECT

2008 ◽  
Vol 26 (5) ◽  
pp. 556-562 ◽  
Author(s):  
Hiroki Kato ◽  
Takuya Yoshikawa ◽  
Naohiko Oku ◽  
Masao Imaizumi ◽  
Masashi Takasawa ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Vascular Dementia ◽  
Parametric Analysis ◽  
Small Vessel Disease ◽  
Small Vessel ◽  
Vessel Disease ◽  
Hmpao Spect

scholarly journals Evaluation of Cerebral Blood Flow Measured by 3D PCASL as Biomarker of Vascular Cognitive Impairment and Dementia (VCID) in a Cohort of Elderly Latinx Subjects at Risk of Small Vessel Disease

2021 ◽  
Vol 15 ◽  
Author(s):  
Kay Jann ◽  
Xingfeng Shao ◽  
Samantha J. Ma ◽  
Steven Y. Cen ◽  
Lina D’Orazio ◽  
...  
Keyword(s):  
At Risk ◽  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Cognitive Impairment ◽  
White Matter ◽  
Small Vessel Disease ◽  
Vascular Cognitive Impairment ◽  
Small Vessel ◽  
Vessel Disease ◽  
Brain White Matter

Cerebral small vessel disease (cSVD) affects arterioles, capillaries, and venules and can lead to cognitive impairments and clinical symptomatology of vascular cognitive impairment and dementia (VCID). VCID symptoms are similar to Alzheimer’s disease (AD) but the neurophysiologic alterations are less well studied, resulting in no established biomarkers. The purpose of this study was to evaluate cerebral blood flow (CBF) measured by 3D pseudo-continuous arterial spin labeling (pCASL) as a potential biomarker of VCID in a cohort of elderly Latinx subjects at risk of cSVD. Forty-five elderly Latinx subjects (12 males, 69 ± 7 years) underwent repeated MRI scans ∼6 weeks apart. CBF was measured using 3D pCASL in the whole brain, white matter and 4 main vascular territories (leptomeningeal anterior, middle, and posterior cerebral artery (leptoACA, leptoMCA, leptoPCA), as well as MCA perforator). The test-retest repeatability of CBF was assessed by intra-class correlation coefficient (ICC) and within-subject coefficient of variation (wsCV). Absolute and relative CBF was correlated with gross cognitive measures and domain specific assessment of executive and memory function, vascular risks, and Fazekas scores and volumes of white matter hyperintensity (WMH). Neurocognitive evaluations were performed using Montreal Cognitive Assessment (MoCA) and neuropsychological test battery in the Uniform Data Set v3 (UDS3). Good to excellent test-retest repeatability was achieved (ICC = 0.77–0.85, wsCV 3–9%) for CBF measurements in the whole brain, white matter, and 4 vascular territories. Relative CBF normalized by global mean CBF in the leptoMCA territory was positively correlated with the executive function composite score, while relative CBF in the leptoMCA and MCA perforator territory was positively correlated with MoCA scores, controlling for age, gender, years of education, and testing language. Relative CBF in WM was negatively correlated with WMH volume and MoCA scores, while relative leptoMCA CBF was positively correlated with WMH volume. Reliable 3D pCASL CBF measurements were achieved in the cohort of elderly Latinx subjects. Relative CBF in the leptomeningeal and perforator MCA territories were the most likely candidate biomarker of VCID. These findings need to be replicated in larger cohorts with greater variability of stages of cSVD.

Sign in / Sign up

Export Citation Format

Share Document