1
|
Katusic ZS, d’Uscio LV, He T. Cerebrovascular Endothelial Dysfunction: Role of BACE1. Arterioscler Thromb Vasc Biol 2024; 44:1737-1747. [PMID: 38868939 PMCID: PMC11269044 DOI: 10.1161/atvbaha.124.320798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2024]
Abstract
Dysfunctional endothelium is increasingly recognized as a mechanistic link between cardiovascular risk factors and dementia, including Alzheimer disease. BACE1 (β-site amyloid-β precursor protein-cleaving enzyme 1) is responsible for β-processing of APP (amyloid-β precursor protein), the first step in the production of Aβ (amyloid-β) peptides, major culprits in the pathogenesis of Alzheimer disease. Under pathological conditions, excessive activation of BACE1 exerts detrimental effects on endothelial function by Aβ-dependent and Aβ-independent mechanisms. High local concentration of Aβ in the brain blood vessels is responsible for the loss of key vascular protective functions of endothelial cells. More recent studies recognized significant contribution of Aβ-independent proteolytic activity of endothelial BACE1 to the pathogenesis of endothelial dysfunction. This review critically evaluates existing evidence supporting the concept that excessive activation of BACE1 expressed in the cerebrovascular endothelium impairs key homeostatic functions of the brain blood vessels. This concept has important therapeutic implications. Indeed, improved understanding of the mechanisms of endothelial dysfunction may help in efforts to develop new approaches to the protection and preservation of healthy cerebrovascular function.
Collapse
Affiliation(s)
- Zvonimir S. Katusic
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota 55902, USA
- Department of Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, Minnesota 55902, USA
| | - Livius V. d’Uscio
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota 55902, USA
- Department of Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, Minnesota 55902, USA
| | - Tongrong He
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota 55902, USA
- Department of Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, Minnesota 55902, USA
| |
Collapse
|
2
|
Lénárt N, Cserép C, Császár E, Pósfai B, Dénes Á. Microglia-neuron-vascular interactions in ischemia. Glia 2024; 72:833-856. [PMID: 37964690 DOI: 10.1002/glia.24487] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 10/24/2023] [Accepted: 10/24/2023] [Indexed: 11/16/2023]
Abstract
Cerebral ischemia is a devastating condition that results in impaired blood flow in the brain leading to acute brain injury. As the most common form of stroke, occlusion of cerebral arteries leads to a characteristic sequence of pathophysiological changes in the brain tissue. The mechanisms involved, and comorbidities that determine outcome after an ischemic event appear to be highly heterogeneous. On their own, the processes leading to neuronal injury in the absence of sufficient blood supply to meet the metabolic demand of the cells are complex and manifest at different temporal and spatial scales. While the contribution of non-neuronal cells to stroke pathophysiology is increasingly recognized, recent data show that microglia, the main immune cells of the central nervous system parenchyma, play previously unrecognized roles in basic physiological processes beyond their inflammatory functions, which markedly change during ischemic conditions. In this review, we aim to discuss some of the known microglia-neuron-vascular interactions assumed to contribute to the acute and delayed pathologies after cerebral ischemia. Because the mechanisms of neuronal injury have been extensively discussed in several excellent previous reviews, here we focus on some recently explored pathways that may directly or indirectly shape neuronal injury through microglia-related actions. These discoveries suggest that modulating gliovascular processes in different forms of stroke and other neurological disorders might have presently unexplored therapeutic potential in combination with neuroprotective and flow restoration strategies.
Collapse
Affiliation(s)
- Nikolett Lénárt
- Momentum Laboratory of Neuroimmunology, Institute of Experimental Medicine, Budapest, Hungary
| | - Csaba Cserép
- Momentum Laboratory of Neuroimmunology, Institute of Experimental Medicine, Budapest, Hungary
| | - Eszter Császár
- Momentum Laboratory of Neuroimmunology, Institute of Experimental Medicine, Budapest, Hungary
| | - Balázs Pósfai
- Momentum Laboratory of Neuroimmunology, Institute of Experimental Medicine, Budapest, Hungary
| | - Ádám Dénes
- Momentum Laboratory of Neuroimmunology, Institute of Experimental Medicine, Budapest, Hungary
| |
Collapse
|
3
|
Deng W, Yi P, Xiong Y, Ying J, Lin Y, Dong Y, Wei G, Wang X, Hua F. Gut Metabolites Acting on the Gut-Brain Axis: Regulating the Functional State of Microglia. Aging Dis 2024; 15:480-502. [PMID: 37548933 PMCID: PMC10917527 DOI: 10.14336/ad.2023.0727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 07/27/2023] [Indexed: 08/08/2023] Open
Abstract
The gut-brain axis is a communication channel that mediates a complex interplay of intestinal flora with the neural, endocrine, and immune systems, linking gut and brain functions. Gut metabolites, a group of small molecules produced or consumed by biochemical processes in the gut, are involved in central nervous system regulation via the highly interconnected gut-brain axis affecting microglia indirectly by influencing the structure of the gut-brain axis or directly affecting microglia function and activity. Accordingly, pathological changes in the central nervous system are connected with changes in intestinal metabolite levels as well as altered microglia function and activity, which may contribute to the pathological process of each neuroinflammatory condition. Here, we discuss the mechanisms by which gut metabolites, for instance, the bile acids, short-chain fatty acids, and tryptophan metabolites, regulate the structure of each component of the gut-brain axis, and explore the important roles of gut metabolites in the central nervous system from the perspective of microglia. At the same time, we highlight the roles of gut metabolites affecting microglia in the pathogenesis of neurodegenerative diseases and neurodevelopmental disorders. Understanding the relationship between microglia, gut microbiota, neuroinflammation, and neurodevelopmental disorders will help us identify new strategies for treating neuropsychiatric disorders.
Collapse
Affiliation(s)
- Wenze Deng
- Department of Anesthesiology, the Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China.
- Key Laboratory of Anesthesiology of Jiangxi Province, Nanchang City, Jiangxi, China.
| | - Pengcheng Yi
- Department of Anesthesiology, the Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China.
- Key Laboratory of Anesthesiology of Jiangxi Province, Nanchang City, Jiangxi, China.
| | - Yanhong Xiong
- Department of Anesthesiology, the Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China.
- Key Laboratory of Anesthesiology of Jiangxi Province, Nanchang City, Jiangxi, China.
| | - Jun Ying
- Department of Anesthesiology, the Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China.
- Key Laboratory of Anesthesiology of Jiangxi Province, Nanchang City, Jiangxi, China.
| | - Yue Lin
- Department of Anesthesiology, the Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China.
- Key Laboratory of Anesthesiology of Jiangxi Province, Nanchang City, Jiangxi, China.
| | - Yao Dong
- Department of Anesthesiology, the Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China.
- Key Laboratory of Anesthesiology of Jiangxi Province, Nanchang City, Jiangxi, China.
| | - Gen Wei
- Department of Anesthesiology, the Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China.
- Key Laboratory of Anesthesiology of Jiangxi Province, Nanchang City, Jiangxi, China.
| | - Xifeng Wang
- Department of Anesthesiology, the First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China.
| | - Fuzhou Hua
- Department of Anesthesiology, the Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China.
- Key Laboratory of Anesthesiology of Jiangxi Province, Nanchang City, Jiangxi, China.
| |
Collapse
|
4
|
Wen J, Satyanarayanan SK, Li A, Yan L, Zhao Z, Yuan Q, Su KP, Su H. Unraveling the impact of Omega-3 polyunsaturated fatty acids on blood-brain barrier (BBB) integrity and glymphatic function. Brain Behav Immun 2024; 115:335-355. [PMID: 37914102 DOI: 10.1016/j.bbi.2023.10.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 10/05/2023] [Accepted: 10/22/2023] [Indexed: 11/03/2023] Open
Abstract
Alzheimer's disease (AD) and other forms of dementia represent major public health challenges but effective therapeutic options are limited. Pathological brain aging is associated with microvascular changes and impaired clearance systems. The application of omega-3 polyunsaturated fatty acids (n-3 or omega-3 PUFAs) is one of the most promising nutritional interventions in neurodegenerative disorders from epidemiological data, clinical and pre-clinical studies. As essential components of neuronal membranes, n-3 PUFAs have shown neuroprotection and anti-inflammatory effects, as well as modulatory effects through microvascular pathophysiology, amyloid-beta (Aβ) clearance and glymphatic pathways. This review meticulously explores these underlying mechanisms that contribute to the beneficial effects of n-3 PUFAs against AD and dementia, synthesizing evidence from both animal and interventional studies.
Collapse
Affiliation(s)
- Jing Wen
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau
| | - Senthil Kumaran Satyanarayanan
- Centre for Regenerative Medicine and Health, Hong Kong Institute of Science & Innovation, Chinese Academy of Sciences, Hong Kong Science Park, Hong Kong
| | - Ang Li
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau
| | - Lingli Yan
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau
| | - Ziai Zhao
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau
| | - Qiuju Yuan
- Centre for Regenerative Medicine and Health, Hong Kong Institute of Science & Innovation, Chinese Academy of Sciences, Hong Kong Science Park, Hong Kong
| | - Kuan-Pin Su
- An-Nan Hospital, China Medical University, Tainan, Taiwan; Department of Psychiatry, China Medical University Hospital, Taichung, Taiwan; Mind-Body Interface Research Center (MBI-Lab), China Medical University Hospital, Taichung, Taiwan.
| | - Huanxing Su
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau.
| |
Collapse
|
5
|
Morton L, Arndt P, Garza AP, Henneicke S, Mattern H, Gonzalez M, Dityatev A, Yilmazer-Hanke D, Schreiber S, Dunay IR. Spatio-temporal dynamics of microglia phenotype in human and murine cSVD: impact of acute and chronic hypertensive states. Acta Neuropathol Commun 2023; 11:204. [PMID: 38115109 PMCID: PMC10729582 DOI: 10.1186/s40478-023-01672-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Accepted: 10/19/2023] [Indexed: 12/21/2023] Open
Abstract
Vascular risk factors such as chronic hypertension are well-established major modifiable factors for the development of cerebral small vessel disease (cSVD). In the present study, our focus was the investigation of cSVD-related phenotypic changes in microglia in human disease and in the spontaneously hypertensive stroke-prone rat (SHRSP) model of cSVD. Our examination of cortical microglia in human post-mortem cSVD cortical tissue revealed distinct morphological microglial features specific to cSVD. We identified enlarged somata, an increase in the territory occupied by thickened microglial processes, and an expansion in the number of vascular-associated microglia. In parallel, we characterized microglia in a rodent model of hypertensive cSVD along different durations of arterial hypertension, i.e., early chronic and late chronic hypertension. Microglial somata were already enlarged in early hypertension. In contrast, at late-stage chronic hypertension, they further exhibited elongated branches, thickened processes, and a reduced ramification index, mirroring the findings in human cSVD. An unbiased multidimensional flow cytometric analysis revealed phenotypic heterogeneity among microglia cells within the hippocampus and cortex. At early-stage hypertension, hippocampal microglia exhibited upregulated CD11b/c, P2Y12R, CD200R, and CD86 surface expression. Detailed analysis of cell subpopulations revealed a unique microglial subset expressing CD11b/c, CD163, and CD86 exclusively in early hypertension. Notably, even at early-stage hypertension, microglia displayed a higher association with cerebral blood vessels. We identified several profound clusters of microglia expressing distinct marker profiles at late chronic hypertensive states. In summary, our findings demonstrate a higher vulnerability of the hippocampus, stage-specific microglial signatures based on morphological features, and cell surface protein expression in response to chronic arterial hypertension. These results indicate the diversity within microglia sub-populations and implicate the subtle involvement of microglia in cSVD pathogenesis.
Collapse
Affiliation(s)
- Lorena Morton
- Institute of Inflammation and Neurodegeneration, Medical Faculty, Health Campus Immunology, Infectiology, and Inflammation (GC-I3), Otto-von-Guericke University, Leipziger Straße 44, 39120, Magdeburg, Germany
| | - Philipp Arndt
- Department of Neurology, Medical Faculty, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
- German Center for Neurodegenerative Diseases (DZNE) Helmholtz Association, Magdeburg, Germany
| | - Alejandra P Garza
- Institute of Inflammation and Neurodegeneration, Medical Faculty, Health Campus Immunology, Infectiology, and Inflammation (GC-I3), Otto-von-Guericke University, Leipziger Straße 44, 39120, Magdeburg, Germany
| | - Solveig Henneicke
- Department of Neurology, Medical Faculty, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
- German Center for Neurodegenerative Diseases (DZNE) Helmholtz Association, Magdeburg, Germany
| | - Hendrik Mattern
- German Center for Neurodegenerative Diseases (DZNE) Helmholtz Association, Magdeburg, Germany
- Faculty of Natural Sciences, Biomedical Magnetic Resonance, Otto-von-Guericke University, Magdeburg, Germany
- Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany
| | - Marilyn Gonzalez
- Institute of Inflammation and Neurodegeneration, Medical Faculty, Health Campus Immunology, Infectiology, and Inflammation (GC-I3), Otto-von-Guericke University, Leipziger Straße 44, 39120, Magdeburg, Germany
| | - Alexander Dityatev
- German Center for Neurodegenerative Diseases (DZNE) Helmholtz Association, Magdeburg, Germany
- Medical Faculty, Otto-von-Guericke University, Magdeburg, Germany
- Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany
| | - Deniz Yilmazer-Hanke
- Clinical Neuroanatomy, Department of Neurology, Institute for Biomedical Research, Ulm University, Ulm, Germany
| | - Stefanie Schreiber
- Department of Neurology, Medical Faculty, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
- German Center for Neurodegenerative Diseases (DZNE) Helmholtz Association, Magdeburg, Germany
- Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany
- Center for Intervention and Research on Adaptive and Maladaptive Brain Circuits Underlying Mental Health (C-I-R-C), Jena-Magdeburg-Halle, Germany
| | - Ildiko R Dunay
- Institute of Inflammation and Neurodegeneration, Medical Faculty, Health Campus Immunology, Infectiology, and Inflammation (GC-I3), Otto-von-Guericke University, Leipziger Straße 44, 39120, Magdeburg, Germany.
- Medical Faculty, Otto-von-Guericke University, Magdeburg, Germany.
- Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany.
- Center for Intervention and Research on Adaptive and Maladaptive Brain Circuits Underlying Mental Health (C-I-R-C), Jena-Magdeburg-Halle, Germany.
| |
Collapse
|
6
|
Zhang M, Tang J, Xia D, Xue Y, Ren X, Huang Q, Shi L, Tang W, Fu J. Evaluation of glymphatic-meningeal lymphatic system with intravenous gadolinium-based contrast-enhancement in cerebral small-vessel disease. Eur Radiol 2023; 33:6096-6106. [PMID: 37410111 DOI: 10.1007/s00330-023-09796-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 03/19/2023] [Accepted: 03/23/2023] [Indexed: 07/07/2023]
Abstract
OBJECTIVE To investigate the feasibility of using noninvasive neuroimaging methods in visualizing and evaluating the clearance of the glymphatic-meningeal lymphatic system (GMLS) in patients with arteriosclerotic cerebral small-vessel disease (CSVD) and controls. METHODS This observational study recruited patients with high-burden CSVD and controls (age 50-80 years). At multiple time points before and after intravenous administration of a contrast agent, three-dimensional (3D) brain volume T1-weighted imaging and 3D Cube T2-fluid attenuated inversion recovery imaging were performed to visualize and assess the clearance of the glymphatics and meningeal lymphatic vessels (mLVs). We measured the signal intensity ratio (SIR) of four regions of interest representing the glymphatics and mLVs at each time point. The clearance rate at 24 h (CR24h) and changes in the SIR from baseline to 24 h (∆SIR) were defined as the clearance function. The analysis of variance was used to evaluate the group differences after adjusting for hypertension. RESULTS A total of 20 CSVD patients and 15 controls were included. Cortical periarterial enhancement and the enhancement of enlarged perivascular spaces in the basal ganglia were respectively observed in 11 (55.00%) and 16 (80.00%) CSVD patients, but in none of controls. All CSVD patients and most of controls (80.00%) showed cortical perivenous enhancement. Para-sinus enhancement was observed in all participants. CSVD patients showed lower CR24h and higher ∆SIR of the glymphatics and mLVs (all p < 0.05). CONCLUSION The impaired drainage of the GMLS in patients with high-burden CSVD could be visually evaluated using noninvasive neuroimaging methods with intravenous gadolinium-based contrast-enhancement. CLINICAL RELEVANCE STATEMENT Dynamic intravenous contrast-enhanced MRI could visually evaluate the impaired drainage of the glymphatic-meningeal lymphatic system in patients with high-burden cerebral small-vessel disease and could help to explore a new therapeutic target. KEY POINTS • Signal intensity changes in regions representing the glymphatic-meningeal lymphatic system (GMLS) can reflect the drainage function based on contrast-enhanced 3D-FLAIR and 3D T1-weighted MRI. • Impaired drainage of the GMLS in patients with high-burden CSVD can be visually evaluated using dynamic intravenous contrast-enhanced MRI. • This direct, noninvasive technique could serve as a basis for further GMLS studies and could help to explore a new therapeutic target in CSVD patients.
Collapse
Affiliation(s)
- Miaoyi Zhang
- Department of Neurology, Huashan Hospital, Fudan University, No.12 Wulumuqi Zhong Road, Shanghai, 200040, China
| | - Jie Tang
- Department of Neurology, Huashan Hospital, Fudan University, No.12 Wulumuqi Zhong Road, Shanghai, 200040, China
| | - Ding Xia
- Department of Radiology, Huashan Hospital, Fudan University, No.12 Wulumuqi Zhong Road, Shanghai, 200040, China
| | - Yang Xue
- Department of Neurology, Huashan Hospital, Fudan University, No.12 Wulumuqi Zhong Road, Shanghai, 200040, China
| | - Xue Ren
- Department of Neurology, Huashan Hospital, Fudan University, No.12 Wulumuqi Zhong Road, Shanghai, 200040, China
| | - Qi Huang
- Department of Neurology, Huashan Hospital, Fudan University, No.12 Wulumuqi Zhong Road, Shanghai, 200040, China
| | - Langfeng Shi
- Department of Neurology, Huashan Hospital, Fudan University, No.12 Wulumuqi Zhong Road, Shanghai, 200040, China
| | - Weijun Tang
- Department of Radiology, Huashan Hospital, Fudan University, No.12 Wulumuqi Zhong Road, Shanghai, 200040, China.
| | - Jianhui Fu
- Department of Neurology, Huashan Hospital, Fudan University, No.12 Wulumuqi Zhong Road, Shanghai, 200040, China.
| |
Collapse
|
7
|
Phua TJ. Understanding human aging and the fundamental cell signaling link in age-related diseases: the middle-aging hypovascularity hypoxia hypothesis. FRONTIERS IN AGING 2023; 4:1196648. [PMID: 37384143 PMCID: PMC10293850 DOI: 10.3389/fragi.2023.1196648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Accepted: 05/23/2023] [Indexed: 06/30/2023]
Abstract
Aging-related hypoxia, oxidative stress, and inflammation pathophysiology are closely associated with human age-related carcinogenesis and chronic diseases. However, the connection between hypoxia and hormonal cell signaling pathways is unclear, but such human age-related comorbid diseases do coincide with the middle-aging period of declining sex hormonal signaling. This scoping review evaluates the relevant interdisciplinary evidence to assess the systems biology of function, regulation, and homeostasis in order to discern and decipher the etiology of the connection between hypoxia and hormonal signaling in human age-related comorbid diseases. The hypothesis charts the accumulating evidence to support the development of a hypoxic milieu and oxidative stress-inflammation pathophysiology in middle-aged individuals, as well as the induction of amyloidosis, autophagy, and epithelial-to-mesenchymal transition in aging-related degeneration. Taken together, this new approach and strategy can provide the clarity of concepts and patterns to determine the causes of declining vascularity hemodynamics (blood flow) and physiological oxygenation perfusion (oxygen bioavailability) in relation to oxygen homeostasis and vascularity that cause hypoxia (hypovascularity hypoxia). The middle-aging hypovascularity hypoxia hypothesis could provide the mechanistic interface connecting the endocrine, nitric oxide, and oxygen homeostasis signaling that is closely linked to the progressive conditions of degenerative hypertrophy, atrophy, fibrosis, and neoplasm. An in-depth understanding of these intrinsic biological processes of the developing middle-aged hypoxia could provide potential new strategies for time-dependent therapies in maintaining healthspan for healthy lifestyle aging, medical cost savings, and health system sustainability.
Collapse
Affiliation(s)
- Teow J. Phua
- Molecular Medicine, NSW Health Pathology, John Hunter Hospital, Newcastle, NSW, Australia
| |
Collapse
|
8
|
Salehi A, Salari S, Jullienne A, Daglian J, Chen K, Baram TZ, Obenaus A. Vascular topology and blood flow are acutely impacted by experimental febrile status epilepticus. J Cereb Blood Flow Metab 2023; 43:84-98. [PMID: 35912523 PMCID: PMC9875348 DOI: 10.1177/0271678x221117625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Febrile status epilepticus (FSE) is an important risk factor for temporal lobe epilepsy and early identification of those at high risk for epilepsy is vital. In a rat model of FSE, we identified an acute (2 hrs) novel MRI signal where reduced T2 relaxation values in the basolateral amygdala (BLA) predicted epilepsy in adulthood; this T2 signal remains incompletely understood and we hypothesized that it may be influenced by vascular topology. Experimental FSE induced in rat pups reduced blood vessel density of the cortical vasculature in a lateralized manner at 2 hrs post FSE. Middle cerebral artery (MCA) exhibited abnormal topology in FSE pups but not in controls. In the BLA, significant vessel junction reductions and decreased vessel diameter were observed, together with a strong trend for reduced vessel length. Perfusion weighted MRI (PWI) was acutely increased cerebral blood flow (CBF) in cortex, amygdala and hippocampus of FSE pups that correlated to decreased T2 relaxation values compared to controls. This is consistent with increased levels of deoxyhemoglobin associated with increased metabolic demand. In summary, FSE acutely modifies vascular topological and CBF in cortex and BLA that may underlie acute MRI signal changes that predict progression to future epilepsy.
Collapse
Affiliation(s)
- Arjang Salehi
- Department of Anatomy and Neurobiology, School of Medicine, University of California Irvine, Irvine CA, USA
| | - Sirus Salari
- Department of Pediatrics, School of Medicine, University of California Irvine, Irvine CA, USA
| | - Amandine Jullienne
- Department of Pediatrics, School of Medicine, University of California Irvine, Irvine CA, USA
| | - Jennifer Daglian
- Department of Anatomy and Neurobiology, School of Medicine, University of California Irvine, Irvine CA, USA
| | - Kevin Chen
- Department of Anatomy and Neurobiology, School of Medicine, University of California Irvine, Irvine CA, USA
| | - Tallie Z Baram
- Department of Anatomy and Neurobiology, School of Medicine, University of California Irvine, Irvine CA, USA.,Department of Pediatrics, School of Medicine, University of California Irvine, Irvine CA, USA
| | - Andre Obenaus
- Department of Anatomy and Neurobiology, School of Medicine, University of California Irvine, Irvine CA, USA.,Department of Pediatrics, School of Medicine, University of California Irvine, Irvine CA, USA
| |
Collapse
|
9
|
Dobrynina LA, Shabalina AA, Shamtieva KV, Kremneva EI, Zabitova MR, Burmak AG, Byrochkina AA, Akhmetshina YI, Gnedovskaya EV, Krotenkova MV. [Nitric oxide availability in cerebral microangiopathy]. Zh Nevrol Psikhiatr Im S S Korsakova 2023; 123:47-54. [PMID: 37682095 DOI: 10.17116/jnevro202312308247] [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] [Indexed: 09/09/2023]
Abstract
OBJECTIVE To develop a test of individual nitric oxide (NO) availability based on changes in erythrocyte rheological properties after incubation with a NO donor and to evaluate the role of these disorders in brain damage and development of cognitive impairment (CI) in cerebral small vessel disease (cSVD). MATERIAL AND METHODS In 73 cSVD patients (48 (65.8%) women, mean age 60.1±6.5), the rheological properties of erythrocytes before and after incubation with 10 μmol/L L-arginine-NO donor were evaluated using a laser-optical rotating cell analyzer, and the blood-brain barrier (BBB) permeability by MRI-T1 dynamic contrast. RESULTS Among the studied parameters of erythrocyte rheological properties, the best characteristic by ROC analysis was the rate of erythrocyte disaggregation (y-dis) after incubation with L-arginine (area under the curve 0.733 (0.609-0.856), sensitivity 67%, specificity 79%). Patients with a y-dis threshold >113 sec-1 had more severe CI, arterial hypertension, white matter lesions, and increased BBB permeability in gray matter and normal-appearing white matter. CONCLUSION The prolonged rate of erythrocyte disaggregation in cSVD patients after incubation with L-arginine indicates the risk for disease progression due to decreased NO bioavailability/disruption of the functional L-arginine-eNOS-NO system. This test can be used to assess individual NO bioavailability and potentially identify indications for modifying therapy with NO donors such as L-arginine. Clinical trials are needed to standardize and evaluate the efficacy of NO donor therapy in patients with cSVD and CI.
Collapse
Affiliation(s)
| | | | | | | | | | - A G Burmak
- Research Center of Neurology, Moscow, Russia
| | | | | | | | | |
Collapse
|
10
|
Wan S, Dandu C, Han G, Guo Y, Ding Y, Song H, Meng R. Plasma inflammatory biomarkers in cerebral small vessel disease: A review. CNS Neurosci Ther 2022; 29:498-515. [PMID: 36478511 PMCID: PMC9873530 DOI: 10.1111/cns.14047] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 10/24/2022] [Accepted: 11/22/2022] [Indexed: 12/12/2022] Open
Abstract
Cerebral small vessel disease (CSVD) is a group of pathological processes affecting small arteries, arterioles, capillaries, and small veins of the brain. It is one of the most common subtypes of cerebrovascular diseases, especially highly prevalent in elderly populations, and is associated with stroke occurrence and recurrence, cognitive impairment, gait disorders, psychological disturbance, and dysuria. Its diagnosis mainly depends on MRI, characterized by recent small subcortical infarcts, lacunes, white matter hyperintensities (WMHs), enlarged perivascular spaces (EPVS), cerebral microbleeds (CMBs), and brain atrophy. While the pathophysiological processes of CSVD are not fully understood at present, inflammation is noticed as playing an important role. Herein, we aimed to review the relationship between plasma inflammatory biomarkers and the MRI features of CSVD, to provide background for further research.
Collapse
Affiliation(s)
- Shuling Wan
- Department of Neurology, National Center for Neurological Disorders, Xuanwu HospitalCapital Medical UniversityBeijingChina,Advanced Center of StrokeBeijing Institute for Brain DisordersBeijingChina
| | - Chaitu Dandu
- Department of NeurosurgeryWayne State University School of MedicineDetroitMichiganUSA
| | - Guangyu Han
- Department of Neurology, National Center for Neurological Disorders, Xuanwu HospitalCapital Medical UniversityBeijingChina,Advanced Center of StrokeBeijing Institute for Brain DisordersBeijingChina
| | - Yibing Guo
- Department of Neurology, National Center for Neurological Disorders, Xuanwu HospitalCapital Medical UniversityBeijingChina,Advanced Center of StrokeBeijing Institute for Brain DisordersBeijingChina
| | - Yuchuan Ding
- Department of NeurosurgeryWayne State University School of MedicineDetroitMichiganUSA
| | - Haiqing Song
- Department of Neurology, National Center for Neurological Disorders, Xuanwu HospitalCapital Medical UniversityBeijingChina,Advanced Center of StrokeBeijing Institute for Brain DisordersBeijingChina
| | - Ran Meng
- Department of Neurology, National Center for Neurological Disorders, Xuanwu HospitalCapital Medical UniversityBeijingChina,Advanced Center of StrokeBeijing Institute for Brain DisordersBeijingChina,Department of NeurosurgeryWayne State University School of MedicineDetroitMichiganUSA
| |
Collapse
|
11
|
Yang Y, Zhao X, Zhu Z, Zhang L. Vascular dementia: A microglia's perspective. Ageing Res Rev 2022; 81:101734. [PMID: 36113763 DOI: 10.1016/j.arr.2022.101734] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 08/28/2022] [Accepted: 09/11/2022] [Indexed: 01/31/2023]
Abstract
Vascular dementia (VaD) is a second most common form of age-related dementia. It is characterized by cognitive impairment associated with vascular pathology, symptoms mainly caused by cerebral damage due to inadequate blood flow to the brain. The pathogenesis of VaD is complex, and a growing body of literature emphasizes on the involvement of microglia in disease development and progression. Here, we review the current knowledge on the role of microglia in regulating neuroinflammation under the pathogenesis of VaD. The commonly used animal and cell models for understanding the disease pathogenesis were summarized. The mechanisms by which microglia contribute to VaD are multifactorial, and we specifically focus on some of the predominant functions of microglia, including chemotaxis, secretory property, phagocytosis, and its crosstalk with other neurovascular unit cells. Finally, potential therapeutic strategies targeting microglia-modulated neuroinflammation are discussed.
Collapse
Affiliation(s)
- Yi Yang
- School of Pharmacy, Hangzhou Normal University, Hangzhou 311121, China; Hangzhou Key Laboratory of Medical Neurobiology, Hangzhou Normal University, Hangzhou 311121, China; Engineering Laboratory of Development and Application of Traditional Chinese Medicines, Collaborative Innovation Center of Traditional Chinese Medicines of Zhejiang Province, Hangzhou Normal University, Hangzhou 311121, China.
| | - Xinyuan Zhao
- School of Pharmacy, Hangzhou Normal University, Hangzhou 311121, China; Hangzhou Key Laboratory of Medical Neurobiology, Hangzhou Normal University, Hangzhou 311121, China
| | - Zirui Zhu
- School of Pharmacy, Hangzhou Normal University, Hangzhou 311121, China; Hangzhou Key Laboratory of Medical Neurobiology, Hangzhou Normal University, Hangzhou 311121, China
| | - Lihui Zhang
- School of Pharmacy, Hangzhou Normal University, Hangzhou 311121, China; Hangzhou Key Laboratory of Medical Neurobiology, Hangzhou Normal University, Hangzhou 311121, China; Engineering Laboratory of Development and Application of Traditional Chinese Medicines, Collaborative Innovation Center of Traditional Chinese Medicines of Zhejiang Province, Hangzhou Normal University, Hangzhou 311121, China.
| |
Collapse
|
12
|
Association of Serum GFAP with Functional and Neurocognitive Outcome in Sporadic Small Vessel Disease. Biomedicines 2022; 10:biomedicines10081869. [PMID: 36009416 PMCID: PMC9405121 DOI: 10.3390/biomedicines10081869] [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: 05/30/2022] [Revised: 07/27/2022] [Accepted: 07/31/2022] [Indexed: 11/25/2022] Open
Abstract
Cerebrospinal fluid (CSF) and serum biomarkers are critical for clinical decision making in neurological diseases. In cerebral small vessel disease (CSVD), white matter hyperintensities (WMH) are an important neuroimaging biomarker, but more blood-based biomarkers capturing different aspects of CSVD pathology are needed. In 42 sporadic CSVD patients, we prospectively analysed WMH on magnetic resonance imaging (MRI) and the biomarkers neurofilament light chain (NfL), glial fibrillary acidic protein (GFAP), chitinase3-like protein 1 (CHI3L1), Tau and Aβ1-42 in CSF and NfL and GFAP in serum. GFAP and CHI3L1 expression was studied in post-mortem brain tissue in additional cases. CSVD cases with higher serum NfL and GFAP levels had a higher modified Rankin Scale (mRS) and NIHSS score and lower CSF Aβ1-42 levels, whereas the CSF NfL and CHI3L1 levels were positively correlated with the WMH load. Moreover, the serum GFAP levels significantly correlated with the neurocognitive functions. Pathological analyses in CSVD revealed a high density of GFAP-immunoreactive fibrillary astrocytic processes in the periventricular white matter and clusters of CHI3L1-immunoreactive astrocytes in the basal ganglia and thalamus. Thus, besides NfL, serum GFAP is a highly promising fluid biomarker of sporadic CSVD, because it does not only correlate with the clinical severity but also correlates with the cognitive function in patients.
Collapse
|
13
|
Cerebral small vessel disease alters neurovascular unit regulation of microcirculation integrity involved in vascular cognitive impairment. Neurobiol Dis 2022; 170:105750. [DOI: 10.1016/j.nbd.2022.105750] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 03/09/2022] [Accepted: 05/08/2022] [Indexed: 12/25/2022] Open
|
14
|
Accurate 3D Reconstruction of White Matter Hyperintensities Based on Attention-Unet. COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE 2022; 2022:3812509. [PMID: 35371291 PMCID: PMC8967522 DOI: 10.1155/2022/3812509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 02/22/2022] [Accepted: 03/07/2022] [Indexed: 11/18/2022]
Abstract
White matter hyperintensities (WMH), also known as white matter osteoporosis, have been clinically proven to be associated with cognitive decline, the risk of cerebral infarction, and dementia. The existing computer automatic measurement technology for the segmentation of patients' WMH does not have a good visualization and quantitative analysis. In this work, the author proposed a new WMH quantitative analysis and 3D reconstruction method for 3D reconstruction of high signal in white matter. At first, the author using ResUnet achieves the high signal segmentation of white matter and adds the attention mechanism into ResUnet to achieve more accurate segmentation. Afterwards, this paper used surface rendering to reconstruct the accurate segmentation results in 3D. Data experiments are conducted on the dataset collected from Shandong Province Third Hospital. After training, the Attention-Unet proposed in this paper is superior to other segmentation models in the segmentation of high signal in white matter and Dice coefficient and MPA reached 92.52% and 92.43%, respectively, thus achieving accurate 3D reconstruction and providing a new idea for quantitative analysis and 3D reconstruction of WMH.
Collapse
|
15
|
Small Vessel Disease: Ancient Description, Novel Biomarkers. Int J Mol Sci 2022; 23:ijms23073508. [PMID: 35408867 PMCID: PMC8998274 DOI: 10.3390/ijms23073508] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 03/20/2022] [Accepted: 03/21/2022] [Indexed: 12/22/2022] Open
Abstract
Small vessel disease (SVD) is one of the most frequent pathological conditions which lead to dementia. Biochemical and neuroimaging might help correctly identify the clinical diagnosis of this relevant brain disease. The microvascular alterations which underlie SVD have common origins, similar cognitive outcomes, and common vascular risk factors. Nevertheless, the arteriolosclerosis process, which underlines SVD development, is based on different mechanisms, not all completely understood, which start from a chronic hypoperfusion state and pass through a chronic brain inflammatory condition, inducing a significant endothelium activation and a consequent tissue remodeling action. In a recent review, we focused on the pathophysiology of SVD, which is complex, involving genetic conditions and different co-morbidities (i.e., diabetes, chronic hypoxia condition, and obesity). Currently, many points still remain unclear and discordant. In this paper, we wanted to focus on new biomarkers, which can be the expression of the endothelial dysfunction, or of the oxidative damage, which could be employed as markers of disease progression or for future targets of therapies. Therefore, we described the altered response to the endothelium-derived nitric oxide-vasodilators (ENOV), prostacyclin, C-reactive proteins, and endothelium-derived hyperpolarizing factors (EDHF). At the same time, due to the concomitant endothelial activation and chronic neuroinflammatory status, we described hypoxia-endothelial-related markers, such as HIF 1 alpha, VEGFR2, and neuroglobin, and MMPs. We also described blood–brain barrier disruption biomarkers and imaging techniques, which can also describe perivascular spaces enlargement and dysfunction. More studies should be necessary, in order to implement these results and give them a clinical benefit.
Collapse
|
16
|
Kurz C, Walker L, Rauchmann BS, Perneczky R. Dysfunction of the blood-brain barrier in Alzheimer's disease: evidence from human studies. Neuropathol Appl Neurobiol 2021; 48:e12782. [PMID: 34823269 DOI: 10.1111/nan.12782] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 11/04/2021] [Accepted: 11/16/2021] [Indexed: 11/28/2022]
Abstract
The pathological processes leading to synapse loss, neuronal loss, brain atrophy and gliosis in Alzheimer´s disease (AD) and their relation to vascular disease and immunological changes are yet to be fully explored. Amyloid-β (Aβ) aggregation, vascular damage and altered immune response interact at the blood-brain-barrier (BBB), affecting the brain endothelium and fuelling neurodegeneration. The aim of the present systematic literature review was to critically appraise and to summarise the published evidence on the clinical correlations and pathophysiological concepts of BBB damage in AD, focusing on human data. The PubMed, Cochrane, Medline and Embase databases were searched for original research articles, systematic reviews and meta-analyses, published in English language from 01/2000 to 07/2021, using the keywords Alzheimer*, amyloid-β or β-amyloid or abeta and brain-blood barrier or BBB. This review shows that specific changes of intercellular structures, reduced expression of transendothelial carriers, induction of vasoactive mediators and activation of both astroglia and monocytes/macrophages characterise blood-brain barrier damage in human AD and AD models. BBB dysfunction on magnetic resonance imaging takes place early in the disease course in AD-specific brain regions. The toxic effects of Aβ and apolipoprotein E (ApoE) are likely to induce a non-cerebral-amyloid-angiopathy-related degeneration of endothelial cells, independently of cerebrovascular disease; however, some of the observed structural changes may just arise with age. Small vessel disease, ApoE, loss of pericytes, pro-inflammatory signalling and cerebral amyloid angiopathy enhance blood-brain-barrier damage. Novel therapeutic approaches for AD, including magnetic resonance-guided focused ultrasound, aim to open the BBB, potentially leading to an improved drainage of Aβ along perivascular channels and increased elimination from the brain. In vitro treatments with ApoE-modifying agents yielded promising effects on modulating BBB function. Reducing cardiovascular risk factors represents one of the most promising interventions for dementia prevention at present. However, further research is needed to elucidate the connection of BBB damage and tau pathology, the role of pro-inflammatory mediators in draining macromolecules and cells from the cerebral parenchyma, including their contribution to cerebral amyloid angiopathy. Improved insight into these pathomechanisms may allow to shed light on the role of Aβ deposition as a primary vs. a secondary event in the complex pathogenesis of AD.
Collapse
Affiliation(s)
- Carolin Kurz
- Department of Psychiatry and Psychotherapy, University Hospital, LMU Munich, Munich, Germany
| | - Lauren Walker
- Translational and Clinical Research Institute, Campus for Ageing and Vitality, Newcastle University
| | - Boris-Stephan Rauchmann
- Department of Psychiatry and Psychotherapy, University Hospital, LMU Munich, Munich, Germany.,Department of Radiology, Department of Radiology, University Hospital, LMU Munich, Munich, Germany
| | - Robert Perneczky
- Department of Psychiatry and Psychotherapy, University Hospital, LMU Munich, Munich, Germany.,German Center for Neurodegenerative Disorders (DZNE) Munich, Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany.,Ageing Epidemiology (AGE) Research Unit, School of Public Health, Imperial College London, London, UK
| |
Collapse
|
17
|
Staszewski J, Dȩbiec A, Skrobowska E, Stȩpień A. Cerebral Vasoreactivity Changes Over Time in Patients With Different Clinical Manifestations of Cerebral Small Vessel Disease. Front Aging Neurosci 2021; 13:727832. [PMID: 34744687 PMCID: PMC8563577 DOI: 10.3389/fnagi.2021.727832] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2021] [Accepted: 09/13/2021] [Indexed: 01/15/2023] Open
Abstract
Objectives: Endothelial dysfunction (ED) has been linked to the pathogenesis of cerebral small vessel disease (SVD). We aimed to assess ED and cerebrovascular reactivity (CVR) in the patients with a diverse manifestation of SVD, with similar and extensive white matter lesions (WMLs, modified Fazekas scale grade ≥2), compared with a control group (CG) without the MRI markers of SVD, matched for age, gender, hypertension, diabetes, and to evaluate the change of CVR following 24 months. Methods: We repeatedly measured the vasomotor reactivity reserve (VMRr) and breath-holding index (BHI) of the middle cerebral artery (MCA) by the transcranial Doppler ultrasound (TCD) techniques in 60 subjects above 60 years with a history of lacunar stroke (LS), vascular dementia (VaD), or parkinsonism (VaP) (20 in each group), and in 20 individuals from a CG. Results: The mean age, frequency of the main vascular risk factors, and sex distribution were similar in the patients with the SVD groups and a CG. The VMRr and the BHI were more severely impaired at baseline (respectively, 56.7 ± 18% and 0.82 ± 0.39) and at follow-up (respectively, 52.3 ± 16.7% and 0.71 ± 0.38) in the patients with SVD regardless of the clinical manifestations (ANOVA, p > 0.1) than in the CG (respectively, baseline VMRr 77.2 ± 15.6%, BHI 1.15 ± 0.47, p < 0.001; follow-up VMRr 74.3 ± 17.6%, BHI 1.11 ± 0.4, p < 0.001). All the assessed CVR measures (VMRr and BHI) significantly decreased over time in the subjects with SVD (Wilcoxon's signed-rank test p = 0.01), but this was not observed in the CG (p > 0.1) and the decrease of CVR measures was not related to the SVD radiological progression (p > 0.1). Conclusions: This study provided evidence that the change in CVR measures is detectable over a 24-month period in patients with different clinical manifestations of SVD. Compared with the patients in CG with similar atherothrombotic risk factors, all the CVR measures (BMRr and BHI) significantly declined over time in the subjects with SVD. The reduction in CVR was not related to the SVD radiological progression.
Collapse
Affiliation(s)
- Jacek Staszewski
- Military Institute of Medicine, Clinic of Neurology, Warsaw, Poland
| | | | - Ewa Skrobowska
- Department of Radiology, Military Institute of Medicine, Warsaw, Poland
| | - Adam Stȩpień
- Military Institute of Medicine, Clinic of Neurology, Warsaw, Poland
| |
Collapse
|
18
|
Tang X, Jiang L, Luo Y, Fan H, Song L, Liu P, Chen Y. Leukoaraiosis and acute ischemic stroke. Eur J Neurosci 2021; 54:6202-6213. [PMID: 34331366 DOI: 10.1111/ejn.15406] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 07/26/2021] [Accepted: 07/26/2021] [Indexed: 11/30/2022]
Abstract
Ischaemic stroke is characterized by high morbidity, high disability rate, high mortality and high recurrence rate, which can have a grave impact on the quality of life of the patients and consequently becomes an economic burden on their families and society. With the developments in imaging technology in recent years, patients with acute cerebral infarction are predominantly more likely to be diagnosed with leukoaraiosis (LA). LA is a common degenerative disease of the nervous system, which is related to cognitive decline, depression, abnormal gait, ischaemic stroke and atherosclerosis. The aetiology of LA is not clear and there is no gold standard for imaging assessment. Related studies have shown that LA has an adverse effect on the prognosis of cerebral infarction, but some experts have contrary beliefs. Hence, we undertook the present review of the literature on the mechanism and the effect of LA on the prognosis of patients with acute ischaemic stroke.
Collapse
Affiliation(s)
- Xiaojia Tang
- Department of Rehabilitation Medicine, Northern Jiangsu People's Hospital Affiliated to Yangzhou University, Yangzhou City, China
| | - Li Jiang
- Department of Neurology, Clinical Medical College, Yangzhou University, Yangzhou City, China
| | - Yuhan Luo
- Health Management Center, People's Hospital of Deyang City, Deyang City, China
| | - Hongyang Fan
- Department of Neurology, Xuzhou Medical University Affiliated Hospital of Lianyungang, Lianyungang City, China
| | - Lilong Song
- Department of Neurology, Shanghai Fourth People's Hospital, Shanghai City, China
| | - Peipei Liu
- Department of Neurology, Clinical Medical College, Yangzhou University, Yangzhou City, China
| | - Yingzhu Chen
- Department of Neurology, Clinical Medical College, Yangzhou University, Yangzhou City, China
| |
Collapse
|
19
|
Islam Y, Leach AG, Smith J, Pluchino S, Coxon CR, Sivakumaran M, Downing J, Fatokun AA, Teixidò M, Ehtezazi T. Physiological and Pathological Factors Affecting Drug Delivery to the Brain by Nanoparticles. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:e2002085. [PMID: 34105297 PMCID: PMC8188209 DOI: 10.1002/advs.202002085] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 01/06/2021] [Indexed: 05/04/2023]
Abstract
The prevalence of neurological/neurodegenerative diseases, such as Alzheimer's disease is known to be increasing due to an aging population and is anticipated to further grow in the decades ahead. The treatment of brain diseases is challenging partly due to the inaccessibility of therapeutic agents to the brain. An increasingly important observation is that the physiology of the brain alters during many brain diseases, and aging adds even more to the complexity of the disease. There is a notion that the permeability of the blood-brain barrier (BBB) increases with aging or disease, however, the body has a defense mechanism that still retains the separation of the brain from harmful chemicals in the blood. This makes drug delivery to the diseased brain, even more challenging and complex task. Here, the physiological changes to the diseased brain and aged brain are covered in the context of drug delivery to the brain using nanoparticles. Also, recent and novel approaches are discussed for the delivery of therapeutic agents to the diseased brain using nanoparticle based or magnetic resonance imaging guided systems. Furthermore, the complement activation, toxicity, and immunogenicity of brain targeting nanoparticles as well as novel in vitro BBB models are discussed.
Collapse
Affiliation(s)
- Yamir Islam
- School of Pharmacy and Biomolecular SciencesLiverpool John Moores UniversityByrom StreetLiverpoolL3 3AFUK
| | - Andrew G. Leach
- School of Pharmacy and Biomolecular SciencesLiverpool John Moores UniversityByrom StreetLiverpoolL3 3AFUK
- Division of Pharmacy and OptometryThe University of ManchesterStopford Building, Oxford RoadManchesterM13 9PTUK
| | - Jayden Smith
- Cambridge Innovation Technologies Consulting (CITC) LimitedSt. John's Innovation CentreCowley RoadCambridgeCB4 0WSUK
| | - Stefano Pluchino
- Department of Clinical NeurosciencesClifford Allbutt Building – Cambridge Biosciences Campus and NIHR Biomedical Research CentreUniversity of CambridgeHills RoadCambridgeCB2 0HAUK
| | - Christopher R. Coxon
- School of Pharmacy and Biomolecular SciencesLiverpool John Moores UniversityByrom StreetLiverpoolL3 3AFUK
- School of Engineering and Physical SciencesHeriot‐Watt UniversityWilliam Perkin BuildingEdinburghEH14 4ASUK
| | - Muttuswamy Sivakumaran
- Department of HaematologyPeterborough City HospitalEdith Cavell CampusBretton Gate PeterboroughPeterboroughPE3 9GZUK
| | - James Downing
- School of Pharmacy and Biomolecular SciencesLiverpool John Moores UniversityByrom StreetLiverpoolL3 3AFUK
| | - Amos A. Fatokun
- School of Pharmacy and Biomolecular SciencesLiverpool John Moores UniversityByrom StreetLiverpoolL3 3AFUK
| | - Meritxell Teixidò
- Institute for Research in Biomedicine (IRB Barcelona)Barcelona Institute of Science and Technology (BIST)Baldiri Reixac 10Barcelona08028Spain
| | - Touraj Ehtezazi
- School of Pharmacy and Biomolecular SciencesLiverpool John Moores UniversityByrom StreetLiverpoolL3 3AFUK
| |
Collapse
|
20
|
Callewaert B, Jones EAV, Himmelreich U, Gsell W. Non-Invasive Evaluation of Cerebral Microvasculature Using Pre-Clinical MRI: Principles, Advantages and Limitations. Diagnostics (Basel) 2021; 11:diagnostics11060926. [PMID: 34064194 PMCID: PMC8224283 DOI: 10.3390/diagnostics11060926] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/16/2021] [Accepted: 05/17/2021] [Indexed: 12/11/2022] Open
Abstract
Alterations to the cerebral microcirculation have been recognized to play a crucial role in the development of neurodegenerative disorders. However, the exact role of the microvascular alterations in the pathophysiological mechanisms often remains poorly understood. The early detection of changes in microcirculation and cerebral blood flow (CBF) can be used to get a better understanding of underlying disease mechanisms. This could be an important step towards the development of new treatment approaches. Animal models allow for the study of the disease mechanism at several stages of development, before the onset of clinical symptoms, and the verification with invasive imaging techniques. Specifically, pre-clinical magnetic resonance imaging (MRI) is an important tool for the development and validation of MRI sequences under clinically relevant conditions. This article reviews MRI strategies providing indirect non-invasive measurements of microvascular changes in the rodent brain that can be used for early detection and characterization of neurodegenerative disorders. The perfusion MRI techniques: Dynamic Contrast Enhanced (DCE), Dynamic Susceptibility Contrast Enhanced (DSC) and Arterial Spin Labeling (ASL), will be discussed, followed by less established imaging strategies used to analyze the cerebral microcirculation: Intravoxel Incoherent Motion (IVIM), Vascular Space Occupancy (VASO), Steady-State Susceptibility Contrast (SSC), Vessel size imaging, SAGE-based DSC, Phase Contrast Flow (PC) Quantitative Susceptibility Mapping (QSM) and quantitative Blood-Oxygenation-Level-Dependent (qBOLD). We will emphasize the advantages and limitations of each strategy, in particular on applications for high-field MRI in the rodent's brain.
Collapse
Affiliation(s)
- Bram Callewaert
- Biomedical MRI Group, University of Leuven, Herestraat 49, bus 505, 3000 Leuven, Belgium; (B.C.); (W.G.)
- CMVB, Center for Molecular and Vascular Biology, University of Leuven, Herestraat 49, bus 911, 3000 Leuven, Belgium;
| | - Elizabeth A. V. Jones
- CMVB, Center for Molecular and Vascular Biology, University of Leuven, Herestraat 49, bus 911, 3000 Leuven, Belgium;
- CARIM, Maastricht University, Universiteitssingel 50, 6200 MD Maastricht, The Netherlands
| | - Uwe Himmelreich
- Biomedical MRI Group, University of Leuven, Herestraat 49, bus 505, 3000 Leuven, Belgium; (B.C.); (W.G.)
- Correspondence:
| | - Willy Gsell
- Biomedical MRI Group, University of Leuven, Herestraat 49, bus 505, 3000 Leuven, Belgium; (B.C.); (W.G.)
| |
Collapse
|
21
|
Walter FR, Santa-Maria AR, Mészáros M, Veszelka S, Dér A, Deli MA. Surface charge, glycocalyx, and blood-brain barrier function. Tissue Barriers 2021; 9:1904773. [PMID: 34003072 DOI: 10.1080/21688370.2021.1904773] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The negative surface charge of brain microvessel endothelial cells is derived from the special composition of their membrane lipids and the thick endothelial surface glycocalyx. They are important elements of the unique defense systems of the blood-brain barrier. The tissue-specific properties, components, function and charge of the brain endothelial glycocalyx have only been studied in detail in the past 15 years. This review highlights the importance of the negative surface charge in the permeability of macromolecules and nanoparticles as well as in drug interactions. We discuss surface charge and glycoxalyx changes in pathologies related to the brain microvasculature and protective measures against glycocalyx shedding and damage. We present biophysical techniques, including a microfluidic chip device, to measure surface charge of living brain endothelial cells and imaging methods for visualization of surface charge and glycocalyx.
Collapse
Affiliation(s)
- Fruzsina R Walter
- Institute of Biophysics, Biological Research Centre, Szeged, Hungary.,Department of Biotechnology, University of Szeged, Szeged, Hungary
| | - Ana R Santa-Maria
- Institute of Biophysics, Biological Research Centre, Szeged, Hungary.,Doctoral School of Biology, University of Szeged, Szeged, Hungary
| | - Mária Mészáros
- Institute of Biophysics, Biological Research Centre, Szeged, Hungary
| | - Szilvia Veszelka
- Institute of Biophysics, Biological Research Centre, Szeged, Hungary
| | - András Dér
- Institute of Biophysics, Biological Research Centre, Szeged, Hungary
| | - Mária A Deli
- Institute of Biophysics, Biological Research Centre, Szeged, Hungary
| |
Collapse
|
22
|
Ronaldson PT, Davis TP. Regulation of blood-brain barrier integrity by microglia in health and disease: A therapeutic opportunity. J Cereb Blood Flow Metab 2020; 40:S6-S24. [PMID: 32928017 PMCID: PMC7687032 DOI: 10.1177/0271678x20951995] [Citation(s) in RCA: 199] [Impact Index Per Article: 49.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The blood-brain barrier (BBB) is a critical regulator of CNS homeostasis. It possesses physical and biochemical characteristics (i.e. tight junction protein complexes, transporters) that are necessary for the BBB to perform this physiological role. Microvascular endothelial cells require support from astrocytes, pericytes, microglia, neurons, and constituents of the extracellular matrix. This intricate relationship implies the existence of a neurovascular unit (NVU). NVU cellular components can be activated in disease and contribute to dynamic remodeling of the BBB. This is especially true of microglia, the resident immune cells of the brain, which polarize into distinct proinflammatory (M1) or anti-inflammatory (M2) phenotypes. Current data indicate that M1 pro-inflammatory microglia contribute to BBB dysfunction and vascular "leak", while M2 anti-inflammatory microglia play a protective role at the BBB. Understanding biological mechanisms involved in microglia activation provides a unique opportunity to develop novel treatment approaches for neurological diseases. In this review, we highlight characteristics of M1 proinflammatory and M2 anti-inflammatory microglia and describe how these distinct phenotypes modulate BBB physiology. Additionally, we outline the role of other NVU cell types in regulating microglial activation and highlight how microglia can be targeted for treatment of disease with a focus on ischemic stroke and Alzheimer's disease.
Collapse
Affiliation(s)
- Patrick T Ronaldson
- Department of Pharmacology, College of Medicine University of Arizona, Tucson, AZ, USA
| | - Thomas P Davis
- Department of Pharmacology, College of Medicine University of Arizona, Tucson, AZ, USA
| |
Collapse
|
23
|
Wright P, Veronese M, Mazibuko N, Turkheimer FE, Rabiner EA, Ballard CG, Williams SCR, Hari Narayanan AK, Osrah B, Williams R, Marques TR, Howes OD, Roncaroli F, O'Sullivan MJ. Patterns of Mitochondrial TSPO Binding in Cerebral Small Vessel Disease: An in vivo PET Study With Neuropathological Comparison. Front Neurol 2020; 11:541377. [PMID: 33178101 PMCID: PMC7596201 DOI: 10.3389/fneur.2020.541377] [Citation(s) in RCA: 4] [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: 03/09/2020] [Accepted: 08/20/2020] [Indexed: 12/11/2022] Open
Abstract
Small vessel disease (SVD) is associated with cognitive impairment in older age and be implicated in vascular dementia. Post-mortem studies show proliferation of activated microglia in the affected white matter. However, the role of inflammation in SVD pathogenesis is incompletely understood and better biomarkers are needed. We hypothesized that expression of the 18 kDa translocator protein (TSPO), a marker of microglial activation, would be higher in SVD. Positron emission tomography (PET) was performed with the second-generation TSPO ligand [11C]PBR28 in 11 participants with SVD. TSPO binding was evaluated by a two-tissue compartment model, with and without a vascular binding component, in white matter hyperintensities (WMH) and normal-appearing white matter (NAWM). In post-mortem tissue, in a separate cohort of individuals with SVD, immunohistochemistry was performed for TSPO and a pan-microglial marker Iba1. Kinetic modeling showed reduced tracer volume and blood volume fraction in WMH compared with NAWM, but a significant increase in vascular binding. Vascular [11C]PBR28 binding was also increased compared with normal-appearing white matter of healthy participants free of SVD. Immunohistochemistry showed a diffuse increase in microglial staining (with Iba1) in sampled tissue in SVD compared with control samples, but with only a subset of microglia staining positively for TSPO. Intense TSPO staining was observed in the vicinity of damaged small blood vessels, which included perivascular macrophages. The results suggest an altered phenotype of activated microglia, with reduced TSPO expression, in the areas of greatest white matter ischemia in SVD, with implications for the interpretation of TSPO PET studies in older individuals or those with vascular risk factors.
Collapse
Affiliation(s)
- Paul Wright
- Department of Neuroimaging, Institute of Psychiatry Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Mattia Veronese
- Department of Neuroimaging, Institute of Psychiatry Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Ndabezinhle Mazibuko
- Department of Neuroimaging, Institute of Psychiatry Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Federico E. Turkheimer
- Department of Neuroimaging, Institute of Psychiatry Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Eugenii A. Rabiner
- Department of Neuroimaging, Institute of Psychiatry Psychology & Neuroscience, King's College London, London, United Kingdom
- Invicro, London, United Kingdom
| | - Clive G. Ballard
- College of Medicine and Health, University of Exeter, Exeter, United Kingdom
| | - Steven C. R. Williams
- Department of Neuroimaging, Institute of Psychiatry Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Avinash Kumar Hari Narayanan
- Division of Neuroscience and Experimental Psychology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
- Manchester Centre for Clinical Neuroscience, Salford Royal Foundation Trust, Salford, United Kingdom
| | - Bahiya Osrah
- Division of Neuroscience and Experimental Psychology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
- Manchester Centre for Clinical Neuroscience, Salford Royal Foundation Trust, Salford, United Kingdom
| | - Ricky Williams
- Division of Neuroscience and Experimental Psychology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
- Manchester Centre for Clinical Neuroscience, Salford Royal Foundation Trust, Salford, United Kingdom
| | - Tiago R. Marques
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Oliver D. Howes
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Federico Roncaroli
- Division of Neuroscience and Experimental Psychology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
- Manchester Centre for Clinical Neuroscience, Salford Royal Foundation Trust, Salford, United Kingdom
| | - Michael J. O'Sullivan
- Department of Neuroimaging, Institute of Psychiatry Psychology & Neuroscience, King's College London, London, United Kingdom
- University of Queensland Centre for Clinical Research, Brisbane, QLD, Australia
- Department of Neurology, The Royal Brisbane and Women's Hospital, Herston, QLD, Australia
| |
Collapse
|
24
|
Ouali Alami N, Tang L, Wiesner D, Commisso B, Bayer D, Weishaupt J, Dupuis L, Wong P, Baumann B, Wirth T, Boeckers TM, Yilmazer-Hanke D, Ludolph A, Roselli F. Multiplexed chemogenetics in astrocytes and motoneurons restore blood-spinal cord barrier in ALS. Life Sci Alliance 2020; 3:3/11/e201900571. [PMID: 32900826 PMCID: PMC7479971 DOI: 10.26508/lsa.201900571] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 08/24/2020] [Accepted: 08/31/2020] [Indexed: 12/20/2022] Open
Abstract
Chemogenetic motoneuron excitation and astrocyte GPCR-Gi signaling restore blood–spinal cord barrier, disrupted in four ALS mouse models, revealing its role in disease progression but not initiation. Blood–spinal cord barrier (BSCB) disruption is thought to contribute to motoneuron (MN) loss in amyotrophic lateral sclerosis (ALS). It is currently unclear whether impairment of the BSCB is the cause or consequence of MN dysfunction and whether its restoration may be directly beneficial. We revealed that SOD1G93A, FUSΔNLS, TDP43G298S, and Tbk1+/− ALS mouse models commonly shared alterations in the BSCB, unrelated to motoneuron loss. We exploit PSAM/PSEM chemogenetics in SOD1G93A mice to demonstrate that the BSCB is rescued by increased MN firing, whereas inactivation worsens it. Moreover, we use DREADD chemogenetics, alone or in multiplexed form, to show that activation of Gi signaling in astrocytes restores BSCB integrity, independently of MN firing, with no effect on MN disease markers and dissociating them from BSCB disruption. We show that astrocytic levels of the BSCB stabilizers Wnt7a and Wnt5a are decreased in SOD1G93A mice and strongly enhanced by Gi signaling, although further decreased by MN inactivation. Thus, we demonstrate that BSCB impairment follows MN dysfunction in ALS pathogenesis but can be reversed by Gi-induced expression of astrocytic Wnt5a/7a.
Collapse
Affiliation(s)
- Najwa Ouali Alami
- Department of Neurology, Ulm University, Ulm, Germany.,International Graduate School in Molecular Medicine Ulm, Ulm, Germany.,Department of Neurology, Clinical Neuroanatomy, Ulm University, Ulm, Germany
| | - Linyun Tang
- Department of Neurology, Ulm University, Ulm, Germany
| | - Diana Wiesner
- Department of Neurology, Ulm University, Ulm, Germany.,German Center for Neurodegenerative Diseases (DZNE), Ulm, Germany
| | | | - David Bayer
- Department of Neurology, Ulm University, Ulm, Germany.,CEMMA Graduate School, Ulm University, Ulm, Germany
| | | | - Luc Dupuis
- Inserm U1118, Mécanismes Centraux et Périphériques de la Neurodégénérescence; Université de Strasbourg, Faculté de Médecine, Strasbourg, France
| | - Phillip Wong
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Bernd Baumann
- Institute of Physiological Chemistry, Ulm University, Ulm, Germany
| | - Thomas Wirth
- Institute of Physiological Chemistry, Ulm University, Ulm, Germany
| | - Tobias M Boeckers
- German Center for Neurodegenerative Diseases (DZNE), Ulm, Germany.,Department of Anatomy and Cell Biology, Ulm University, Ulm, Germany
| | | | - Albert Ludolph
- Department of Neurology, Ulm University, Ulm, Germany.,German Center for Neurodegenerative Diseases (DZNE), Ulm, Germany
| | - Francesco Roselli
- Department of Neurology, Ulm University, Ulm, Germany .,German Center for Neurodegenerative Diseases (DZNE), Ulm, Germany
| |
Collapse
|
25
|
Ristori E, Donnini S, Ziche M. New Insights Into Blood-Brain Barrier Maintenance: The Homeostatic Role of β-Amyloid Precursor Protein in Cerebral Vasculature. Front Physiol 2020; 11:1056. [PMID: 32973564 PMCID: PMC7481479 DOI: 10.3389/fphys.2020.01056] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 07/31/2020] [Indexed: 12/11/2022] Open
Abstract
Cerebrovascular homeostasis is maintained by the blood-brain barrier (BBB), a highly selective structure that separates the peripheral blood circulation from the brain and protects the central nervous system (CNS). Dysregulation of BBB function is the precursor of several neurodegenerative diseases including Alzheimer’s disease (AD) and cerebral amyloid angiopathy (CAA), both related to β-amyloid (Aβ) accumulation and deposition. The origin of BBB dysfunction before and/or during CAA and AD onset is not known. Several studies raise the possibility that vascular dysfunction could be an early step in these diseases and could even precede significant Aβ deposition. Though accumulation of neuron-derived Aβ peptides is considered the primary influence driving AD and CAA pathogenesis, recent studies highlighted the importance of the physiological role of the β-amyloid precursor protein (APP) in endothelial cell homeostasis, suggesting a potential role of this protein in maintaining vascular stability. In this review, we will discuss the physiological function of APP and its cleavage products in the vascular endothelium. We further suggest how loss of APP homeostatic regulation in the brain vasculature could lead toward pathological outcomes in neurodegenerative disorders.
Collapse
Affiliation(s)
- Emma Ristori
- Department of Life Sciences, University of Siena, Siena, Italy
| | - Sandra Donnini
- Department of Life Sciences, University of Siena, Siena, Italy
| | - Marina Ziche
- Department of Medicine, Surgery and Neuroscience, University of Siena, Siena, Italy
| |
Collapse
|
26
|
Abdelhak A, Huss A, Brück A, Sebert U, Mayer B, Müller HP, Tumani H, Otto M, Yilmazer-Hanke D, Ludolph AC, Kassubek J, Pinkhardt E, Neugebauer H. Optical coherence tomography-based assessment of retinal vascular pathology in cerebral small vessel disease. Neurol Res Pract 2020; 2:13. [PMID: 33324919 PMCID: PMC7650138 DOI: 10.1186/s42466-020-00062-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 04/29/2020] [Indexed: 12/13/2022] Open
Abstract
Background Cerebral small vessel disease (CSVD) is a disorder of brain vasculature that causes various structural changes in the brain parenchyma, and is associated with various clinical symptoms such as cognitive impairment and gait disorders. Structural changes of brain arterioles cannot be visualized with routine imaging techniques in vivo. However, optical coherence tomography (OCT) is thought to be a “window to the brain”. Thus, retinal vessel parameters may correlate with CSVD characteristic brain lesions and cerebrospinal fluid biomarkers (CSF) of the neuropathological processes in CSVD like endothelial damage, microglial activation and neuroaxonal damage. Methods We applied OCT-based assessment of retinal vessels, magnetic resonance imaging (MRI), and CSF biomarker analysis in a monocentric prospective cohort of 24 patients with sporadic CSVD related stroke and cognitive impairment. MRI lesions were defined according to the STandards for ReportIng Vascular changes on nEuroimaging (STRIVE). Biomarkers were assessed using commercially available ELISA kits. Owing to the unavailability of an age-matched control-group lacking MRI-characteristics of CSVD, we compared the retinal vessel parameters in CSVD patients (73.8 ± 8.5 years) with a younger group of healthy controls (51.0 ± 16.0 years) by using an age- and sex-adjusted multiple linear regression analysis model. Results Among the parameters measured with OCT, the Wall to Lumen Ratio (WLR) but not Mean Wall Thickness (MWT) of the superior branch of the retinal artery correlated significantly with the volume of white matter hyperintensities on MRI (rs = − 0.5) and with CSF-levels of Chitinase 3 like 1 protein (rs = − 0.6), zona occludens 1 protein (rs = − 0.5) and GFAP (rs = − 0.4). MWT and WLR were higher in CSVD than in controls (28.9 μm vs. 23.9 μm, p = 0.001 and 0.32 vs. 0.25, p = 0.001). Conclusions In this exploratory study, WLR correlated with the volume of white matter hyperintensities, and markers of vascular integrity, microglial activation, and neuroaxonal damage in CSVD. Further prospective studies should clarify whether retinal vessel parameters and CSF biomarkers may serve to monitor the natural course and treatment effects in clinical studies on CSVD.
Collapse
Affiliation(s)
- A Abdelhak
- Department of Neurology & Stroke, University Hospital of Tübingen, Tübingen, Germany.,Department of Neurology, University Hospital of Ulm, Ulm, Germany
| | - A Huss
- Department of Neurology, University Hospital of Ulm, Ulm, Germany
| | - A Brück
- Department of Neurology, University Hospital of Ulm, Ulm, Germany
| | - U Sebert
- Department of Neurology, University Hospital of Ulm, Ulm, Germany
| | - B Mayer
- Institute of Epidemiology and Medical Biometry, Ulm, Germany
| | - H P Müller
- Department of Neurology, University Hospital of Ulm, Ulm, Germany
| | - H Tumani
- Department of Neurology, University Hospital of Ulm, Ulm, Germany.,Specialty Clinic of Neurology Dietenbronn, Schwendi, Germany
| | - M Otto
- Department of Neurology, University Hospital of Ulm, Ulm, Germany
| | - D Yilmazer-Hanke
- Clinical Neuroanatomy Section, Department of Neurology, Ulm, Germany
| | - A C Ludolph
- Department of Neurology, University Hospital of Ulm, Ulm, Germany
| | - J Kassubek
- Department of Neurology, University Hospital of Ulm, Ulm, Germany
| | - E Pinkhardt
- Department of Neurology, University Hospital of Ulm, Ulm, Germany
| | - H Neugebauer
- Department of Neurology, University Hospital of Ulm, Ulm, Germany.,Department of Neurology, University of Wuerzburg, Würzburg, Germany
| |
Collapse
|
27
|
Yilmazer-Hanke D, Mayer T, Müller HP, Neugebauer H, Abaei A, Scheuerle A, Weis J, Forsberg KME, Althaus K, Meier J, Ludolph AC, Del Tredici K, Braak H, Kassubek J, Rasche V. Histological correlates of postmortem ultra-high-resolution single-section MRI in cortical cerebral microinfarcts. Acta Neuropathol Commun 2020; 8:33. [PMID: 32169123 PMCID: PMC7071593 DOI: 10.1186/s40478-020-00900-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2019] [Accepted: 02/21/2020] [Indexed: 02/07/2023] Open
Abstract
The identification of cerebral microinfarctions with magnetic resonance imaging (MRI) and histological methods remains challenging in aging and dementia. Here, we matched pathological changes in the microvasculature of cortical cerebral microinfarcts to MRI signals using single 100 μm-thick histological sections scanned with ultra-high-resolution 11.7 T MRI. Histologically, microinfarcts were located in superficial or deep cortical layers or transcortically, compatible with the pattern of layer-specific arteriolar blood supply of the cerebral cortex. Contrary to acute microinfarcts, at chronic stages the core region of microinfarcts showed pallor with extracellular accumulation of lipofuscin and depletion of neurons, a dense meshwork of collagen 4-positive microvessels with numerous string vessels, CD68-positive macrophages and glial fibrillary acidic protein (GFAP)-positive astrocytes. In MRI scans, cortical microinfarcts at chronic stages, called chronic cortical microinfarcts here, gave hypointense signals in T1-weighted and hyperintense signals in T2-weighted images when thinning of the tissue and cavitation and/or prominent iron accumulation were present. Iron accumulation in chronic microinfarcts, histologically verified with Prussian blue staining, also produced strong hypointense T2*-weighted signals. In summary, the microinfarct core was occupied by a dense microvascular meshwork with string vessels, which was invaded by macrophages and astroglia and contained various degrees of iron accumulation. While postmortem ultra-high-resolution single-section imaging improved MRI-histological matching and the structural characterization of chronic cortical cerebral microinfarcts, miniscule microinfarcts without thinning or iron accumulation could not be detected with certainty in the MRI scans. Moreover, string vessels at the infarct margin indicate disturbances in the microcirculation in and around microinfarcts, which might be exploitable in the diagnostics of cortical cerebral microinfarcts with MRI in vivo.
Collapse
|
28
|
Moretti R, Caruso P. Small Vessel Disease-Related Dementia: An Invalid Neurovascular Coupling? Int J Mol Sci 2020; 21:E1095. [PMID: 32046035 PMCID: PMC7036993 DOI: 10.3390/ijms21031095] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Revised: 02/04/2020] [Accepted: 02/04/2020] [Indexed: 12/18/2022] Open
Abstract
The arteriosclerosis-dependent alteration of brain perfusion is one of the major determinants in small vessel disease, since small vessels have a pivotal role in the brain's autoregulation. Nevertheless, as far as we know, endothelium distress can potentiate the flow dysregulation and lead to subcortical vascular dementia that is related to small vessel disease (SVD), also being defined as subcortical vascular dementia (sVAD), as well as microglia activation, chronic hypoxia and hypoperfusion, vessel-tone dysregulation, altered astrocytes, and pericytes functioning blood-brain barrier disruption. The molecular basis of this pathology remains controversial. The apparent consequence (or a first event, too) is the macroscopic alteration of the neurovascular coupling. Here, we examined the possible mechanisms that lead a healthy aging process towards subcortical dementia. We remarked that SVD and white matter abnormalities related to age could be accelerated and potentiated by different vascular risk factors. Vascular function changes can be heavily influenced by genetic and epigenetic factors, which are, to the best of our knowledge, mostly unknown. Metabolic demands, active neurovascular coupling, correct glymphatic process, and adequate oxidative and inflammatory responses could be bulwarks in defense of the correct aging process; their impairments lead to a potentially catastrophic and non-reversible condition.
Collapse
Affiliation(s)
- Rita Moretti
- Neurology Clinic, Department of Medical, Surgical and Health Sciences, University of Trieste, 34149 Trieste, Italy;
| | | |
Collapse
|