1
|
Salminen A. Aryl hydrocarbon receptor impairs circadian regulation in Alzheimer's disease: Potential impact on glymphatic system dysfunction. Eur J Neurosci 2024; 60:3901-3920. [PMID: 38924210 DOI: 10.1111/ejn.16450] [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: 01/17/2024] [Revised: 05/23/2024] [Accepted: 06/10/2024] [Indexed: 06/28/2024]
Abstract
Circadian clocks maintain diurnal rhythms of sleep-wake cycle of 24 h that regulate not only the metabolism of an organism but also many other periodical processes. There is substantial evidence that circadian regulation is impaired in Alzheimer's disease. Circadian clocks regulate many properties known to be disturbed in Alzheimer's patients, such as the integrity of the blood-brain barrier (BBB) as well as the diurnal glymphatic flow that controls waste clearance from the brain. Interestingly, an evolutionarily conserved transcription factor, that is, aryl hydrocarbon receptor (AhR), impairs the function of the core clock proteins and thus could disturb diurnal rhythmicity in the BBB. There is abundant evidence that the activation of AhR signalling inhibits the expression of the major core clock proteins, such as the brain and muscle arnt-like 1 (BMAL1), clock circadian regulator (CLOCK) and period circadian regulator 1 (PER1) in different experimental models. The expression of AhR is robustly increased in the brains of Alzheimer's patients, and protein level is enriched in astrocytes of the BBB. It seems that AhR signalling inhibits glymphatic flow since it is known that (i) activation of AhR impairs the function of the BBB, which is cooperatively interconnected with the glymphatic system in the brain, and (ii) neuroinflammation and dysbiosis of gut microbiota generate potent activators of AhR, which are able to impair glymphatic flow. I will examine current evidence indicating that activation of AhR signalling could disturb circadian functions of the BBB and impair glymphatic flow and thus be involved in the development of Alzheimer's pathology.
Collapse
Affiliation(s)
- Antero Salminen
- Department of Neurology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland
| |
Collapse
|
2
|
Avila A, Zhang SL. A circadian clock regulates the blood-brain barrier across phylogeny. VITAMINS AND HORMONES 2024; 126:241-287. [PMID: 39029975 DOI: 10.1016/bs.vh.2024.04.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/21/2024]
Abstract
As the central regulatory system of an organism, the brain is responsible for overseeing a wide variety of physiological processes essential for an organism's survival. To maintain the environment necessary for neurons to function, the brain requires highly selective uptake and elimination of specific molecules through the blood-brain barrier (BBB). As an organism's activities vary throughout the day, how does the BBB adapt to meet the changing needs of the brain? A mechanism is through temporal regulation of BBB permeability via its circadian clock, which will be the focal point of this chapter. To comprehend the circadian clock's role within the BBB, we will first examine the anatomy of the BBB and the transport mechanisms enabling it to fulfill its role as a restrictive barrier. Next, we will define the circadian clock, and the discussion will encompass an introduction to circadian rhythms, the Transcription-Translation Feedback Loop (TTFL) as the mechanistic basis of circadian timekeeping, and the organization of tissue clocks found in organisms. Then, we will cover the role of the circadian rhythms in regulating the cellular mechanisms and functions of the BBB. We discuss the implications of this regulation in influencing sleep behavior, the progression of neurodegenerative diseases, and finally drug delivery for treatment of neurological diseases.
Collapse
Affiliation(s)
- Ashley Avila
- Cell Biology Department, Emory University, Atlanta, GA, United States
| | - Shirley L Zhang
- Cell Biology Department, Emory University, Atlanta, GA, United States.
| |
Collapse
|
3
|
Brendstrup-Brix K, Ulv Larsen SM, Lee HH, Knudsen GM. Perivascular space diffusivity and brain microstructural measures are associated with circadian time and sleep quality. J Sleep Res 2024:e14226. [PMID: 38676409 DOI: 10.1111/jsr.14226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 04/04/2024] [Accepted: 04/12/2024] [Indexed: 04/28/2024]
Abstract
The glymphatic system is centred around brain cerebrospinal fluid flow and is enhanced during sleep, and the synaptic homeostasis hypothesis proposes that sleep acts on brain microstructure by selective synaptic downscaling. While so far primarily studied in animals, we here examine in humans if brain diffusivity and microstructure is related to time of day, sleep quality and cognitive performance. We use diffusion weighted images from 916 young healthy individuals, aged between 22 and 37 years, collected as part of the Human Connectome Project to assess diffusion tensor image analysis along the perivascular space index, white matter fractional anisotropy, intra-neurite volume fraction and extra-neurite mean diffusivity. Next, we examine if these measures are associated with circadian time of acquisition, the Pittsburgh Sleep Quality Index (high scores correspond to low sleep quality) and age-adjusted cognitive function total composite score. Consistent with expectations, we find that diffusion tensor image analysis along the perivascular space index and orbitofrontal grey matter extra-neurite mean diffusivity are negatively and white matter fractional anisotropy positively correlated with circadian time. Further, we find that grey matter intra-neurite volume fraction correlates positively with Pittsburgh Sleep Quality Index, and that this correlation is driven by sleep duration. Finally, we find positive correlations between grey matter intra-neurite volume fraction and cognitive function total composite score, as well as negative interaction effects between cognitive function total composite score and Pittsburgh Sleep Quality Index on grey matter intra-neurite volume fraction. Our findings propose that perivascular flow is under circadian control and that sleep downregulates the intra-neurite volume in healthy adults with positive impact on cognitive function.
Collapse
Affiliation(s)
- Kristoffer Brendstrup-Brix
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sara Marie Ulv Larsen
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Hong-Hsi Lee
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, Massachusetts, USA
- Harvard Medical School, Boston, Massachusetts, USA
| | - Gitte Moos Knudsen
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| |
Collapse
|
4
|
Abstract
The brain is a complex organ, fundamentally changing across the day to perform basic functions like sleep, thought, and regulating whole-body physiology. This requires a complex symphony of nutrients, hormones, ions, neurotransmitters and more to be properly distributed across the brain to maintain homeostasis throughout 24 hours. These solutes are distributed both by the blood and by cerebrospinal fluid. Cerebrospinal fluid contents are distinct from the general circulation because of regulation at brain barriers including the choroid plexus, glymphatic system, and blood-brain barrier. In this review, we discuss the overlapping circadian (≈24-hour) rhythms in brain fluid biology and at the brain barriers. Our goal is for the reader to gain both a fundamental understanding of brain barriers alongside an understanding of the interactions between these fluids and the circadian timing system. Ultimately, this review will provide new insight into how alterations in these finely tuned clocks may lead to pathology.
Collapse
Affiliation(s)
- Velia S Vizcarra
- Center for Translational Neuromedicine, University of Rochester Medical Center, Rochester, NY, 14642, USA
| | - Ryann M Fame
- Department of Neurosurgery, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Lauren M Hablitz
- Center for Translational Neuromedicine, University of Rochester Medical Center, Rochester, NY, 14642, USA
| |
Collapse
|
5
|
Alghanimy A, Work LM, Holmes WM. The glymphatic system and multiple sclerosis: An evolving connection. Mult Scler Relat Disord 2024; 83:105456. [PMID: 38266608 DOI: 10.1016/j.msard.2024.105456] [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: 01/14/2024] [Accepted: 01/18/2024] [Indexed: 01/26/2024]
Abstract
Multiple sclerosis (MS) is a complex autoimmune disorder that affects the central nervous system, resulting in demyelination and an array of neurological manifestations. Recently, there has been significant scientific interest in the glymphatic system, which operates as a waste-clearance system for the brain. This article reviews the existing literature, and explores potential links between the glymphatic system and MS, shedding light on its evolving significance in the context of MS pathogenesis. The authors consider the pathophysiological implications of glymphatic dysfunction in MS, the impact of disrupted sleep on glymphatic function, and the bidirectional relationship between MS and sleep disturbances. By offering an understanding of the intricate interplay between the glymphatic system and MS, this review provides valuable insights which may lead to improved diagnostic techniques and more effective therapeutic interventions.
Collapse
Affiliation(s)
- Alaa Alghanimy
- School of Psychology and Neuroscience, College of Medicine, Veterinary and Life Science, University of Glasgow, Glasgow G61 1QH, United Kingdom; Radiological Sciences Department, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia.
| | - Lorraine M Work
- School of Cardiovascular and Metabolic Health, College of Medicine, Veterinary and Life Science, University of Glasgow, Glasgow G12 8TA, United Kingdom
| | - William M Holmes
- School of Psychology and Neuroscience, College of Medicine, Veterinary and Life Science, University of Glasgow, Glasgow G61 1QH, United Kingdom
| |
Collapse
|
6
|
Oka S, Ogawa A, Osada T, Tanaka M, Nakajima K, Kamagata K, Aoki S, Oshima Y, Tanaka S, Kirino E, Nakamura TJ, Konishi S. Diurnal Variation of Brain Activity in the Human Suprachiasmatic Nucleus. J Neurosci 2024; 44:e1730232024. [PMID: 38238074 PMCID: PMC10883613 DOI: 10.1523/jneurosci.1730-23.2024] [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: 09/13/2023] [Revised: 11/29/2023] [Accepted: 01/09/2024] [Indexed: 02/23/2024] Open
Abstract
The suprachiasmatic nucleus (SCN) is the central clock for circadian rhythms. Animal studies have revealed daily rhythms in the neuronal activity in the SCN. However, the circadian activity of the human SCN has remained elusive. In this study, to reveal the diurnal variation of the SCN activity in humans, we localized the SCN by employing an areal boundary mapping technique to resting-state functional images and investigated the SCN activity using perfusion imaging. In the first experiment (n = 27, including both sexes), we scanned each participant four times a day, every 6 h. Higher activity was observed at noon, while lower activity was recorded in the early morning. In the second experiment (n = 20, including both sexes), the SCN activity was measured every 30 min for 6 h from midnight to dawn. The results showed that the SCN activity gradually decreased and was not associated with the electroencephalography. Furthermore, the SCN activity was compatible with the rodent SCN activity after switching off the lights. These results suggest that the diurnal variation of the human SCN follows the zeitgeber cycles of nocturnal and diurnal mammals and is modulated by physical lights rather than the local time.
Collapse
Affiliation(s)
- Satoshi Oka
- Department of Neurophysiology, Juntendo University School of Medicine, Tokyo 113-8421, Japan
| | - Akitoshi Ogawa
- Department of Neurophysiology, Juntendo University School of Medicine, Tokyo 113-8421, Japan
| | - Takahiro Osada
- Department of Neurophysiology, Juntendo University School of Medicine, Tokyo 113-8421, Japan
| | - Masaki Tanaka
- Department of Neurophysiology, Juntendo University School of Medicine, Tokyo 113-8421, Japan
| | - Koji Nakajima
- Department of Neurophysiology, Juntendo University School of Medicine, Tokyo 113-8421, Japan
- Department of Orthopaedic Surgery, The University of Tokyo School of Medicine, Tokyo 113-0033, Japan
| | - Koji Kamagata
- Department of Radiology, Juntendo University School of Medicine, Tokyo 113-8421, Japan
| | - Shigeki Aoki
- Department of Radiology, Juntendo University School of Medicine, Tokyo 113-8421, Japan
| | - Yasushi Oshima
- Department of Orthopaedic Surgery, The University of Tokyo School of Medicine, Tokyo 113-0033, Japan
| | - Sakae Tanaka
- Department of Orthopaedic Surgery, The University of Tokyo School of Medicine, Tokyo 113-0033, Japan
| | - Eiji Kirino
- Department of Psychiatry, Juntendo Shizuoka Hospital, Shizuoka 410-2211, Japan
| | - Takahiro J Nakamura
- Laboratory of Animal Physiology, School of Agriculture, Meiji University, Kanagawa 214-8571, Japan
| | - Seiki Konishi
- Department of Neurophysiology, Juntendo University School of Medicine, Tokyo 113-8421, Japan
- Sportology Center, Juntendo University School of Medicine, Tokyo 113-8421, Japan
- Research Institute for Diseases of Old Age, Juntendo University School of Medicine, Tokyo 113-8421, Japan
- Advanced Research Institute for Health Science, Juntendo University School of Medicine, Tokyo 113-8421, Japan
| |
Collapse
|
7
|
Wu L, Zhang Z, Liang X, Wang Y, Cao Y, Li M, Zhou F. Glymphatic system dysfunction in recovered patients with mild COVID-19: A DTI-ALPS study. iScience 2024; 27:108647. [PMID: 38155770 PMCID: PMC10753064 DOI: 10.1016/j.isci.2023.108647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Revised: 10/07/2023] [Accepted: 12/04/2023] [Indexed: 12/30/2023] Open
Abstract
Central nervous sequelae are often reported in recovered patients with COVID-19. It is not clear whether recovered COVID-19 patients have glymphatic impairment and clinical correlation. In this study, we demonstrated that mild COVID-19 patients experienced asymmetric bilateral glymphatic function decline after four months of recovery, and the decrease in glymphatic function was more obvious in older recovered patients. Our results further showed that recovered patients with right-sided glymphatic dysfunction experienced a greater proportion of cognitive decline (MoCA score <26) than patients with left-sided glymphatic dysfunction. With COVID-19 infection over 90% of the general population currently, future studies of cognitive disorders in the older population should consider the impact of COVID-19 infection.
Collapse
Affiliation(s)
- Lin Wu
- Department of Radiology, The First Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, Jiangxi, China
- Jiangxi Province Medical Imaging Research Institute, Nanchang, Jiangxi, China
- Clinical Research Center For Medical Imaging, Nanchang, Jiangxi, China
| | - Zhi Zhang
- Department of Radiology, The First Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, Jiangxi, China
- Jiangxi Province Medical Imaging Research Institute, Nanchang, Jiangxi, China
- Clinical Research Center For Medical Imaging, Nanchang, Jiangxi, China
| | - Xiao Liang
- Department of Radiology, The First Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, Jiangxi, China
- Jiangxi Province Medical Imaging Research Institute, Nanchang, Jiangxi, China
- Clinical Research Center For Medical Imaging, Nanchang, Jiangxi, China
| | - Yao Wang
- Department of Radiology, The First Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, Jiangxi, China
- Jiangxi Province Medical Imaging Research Institute, Nanchang, Jiangxi, China
- Clinical Research Center For Medical Imaging, Nanchang, Jiangxi, China
| | - Yuan Cao
- Department of Psychiatry and Psychotherapy, Jena University Hospital, Jena, Germany
| | - Meng Li
- Department of Psychiatry and Psychotherapy, Jena University Hospital, Jena, Germany
- Center for Intervention and Research on adaptive and maladaptive brain Circuits underlying mental health (C-I-R-C), Jena-Magdeburg-Halle, Germany
| | - Fuqing Zhou
- Department of Radiology, The First Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, Jiangxi, China
- Jiangxi Province Medical Imaging Research Institute, Nanchang, Jiangxi, China
- Clinical Research Center For Medical Imaging, Nanchang, Jiangxi, China
| |
Collapse
|
8
|
Gędek A, Koziorowski D, Szlufik S. Assessment of factors influencing glymphatic activity and implications for clinical medicine. Front Neurol 2023; 14:1232304. [PMID: 37767530 PMCID: PMC10520725 DOI: 10.3389/fneur.2023.1232304] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 08/22/2023] [Indexed: 09/29/2023] Open
Abstract
The glymphatic system is a highly specialized fluid transport system in the central nervous system. It enables the exchange of the intercellular fluid of the brain, regulation of the movement of this fluid, clearance of unnecessary metabolic products, and, potentially, brain immunity. In this review, based on the latest scientific reports, we present the mechanism of action and function of the glymphatic system and look at the role of factors influencing its activity. Sleep habits, eating patterns, coexisting stress or hypertension, and physical activity can significantly affect glymphatic activity. Modifying them can help to change lives for the better. In the next section of the review, we discuss the connection between the glymphatic system and neurological disorders. Its association with many disease entities suggests that it plays a major role in the physiology of the whole brain, linking many pathophysiological pathways of individual diseases.
Collapse
Affiliation(s)
- Adam Gędek
- Department of Neurology, Faculty of Health Sciences, Medical University of Warsaw, Warsaw, Poland
- Praski Hospital, Warsaw, Poland
| | - Dariusz Koziorowski
- Department of Neurology, Faculty of Health Sciences, Medical University of Warsaw, Warsaw, Poland
| | - Stanisław Szlufik
- Department of Neurology, Faculty of Health Sciences, Medical University of Warsaw, Warsaw, Poland
| |
Collapse
|
9
|
Li Y, Que M, Wang X, Zhan G, Zhou Z, Luo X, Li S. Exploring Astrocyte-Mediated Mechanisms in Sleep Disorders and Comorbidity. Biomedicines 2023; 11:2476. [PMID: 37760916 PMCID: PMC10525869 DOI: 10.3390/biomedicines11092476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 08/25/2023] [Accepted: 08/30/2023] [Indexed: 09/29/2023] Open
Abstract
Astrocytes, the most abundant cells in the brain, are integral to sleep regulation. In the context of a healthy neural environment, these glial cells exert a profound influence on the sleep-wake cycle, modulating both rapid eye movement (REM) and non-REM sleep phases. However, emerging literature underscores perturbations in astrocytic function as potential etiological factors in sleep disorders, either as protopathy or comorbidity. As known, sleep disorders significantly increase the risk of neurodegenerative, cardiovascular, metabolic, or psychiatric diseases. Meanwhile, sleep disorders are commonly screened as comorbidities in various neurodegenerative diseases, epilepsy, and others. Building on existing research that examines the role of astrocytes in sleep disorders, this review aims to elucidate the potential mechanisms by which astrocytes influence sleep regulation and contribute to sleep disorders in the varied settings of brain diseases. The review emphasizes the significance of astrocyte-mediated mechanisms in sleep disorders and their associated comorbidities, highlighting the need for further research.
Collapse
Affiliation(s)
- Yujuan Li
- Department of Anesthesiology, Hubei Key Laboratory of Geriatric Anesthesia and Perioperative Brain Health, Wuhan Clinical Research Center for Geriatric Anesthesia, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430074, China; (Y.L.); (M.Q.); (X.W.); (G.Z.); (Z.Z.)
| | - Mengxin Que
- Department of Anesthesiology, Hubei Key Laboratory of Geriatric Anesthesia and Perioperative Brain Health, Wuhan Clinical Research Center for Geriatric Anesthesia, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430074, China; (Y.L.); (M.Q.); (X.W.); (G.Z.); (Z.Z.)
| | - Xuan Wang
- Department of Anesthesiology, Hubei Key Laboratory of Geriatric Anesthesia and Perioperative Brain Health, Wuhan Clinical Research Center for Geriatric Anesthesia, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430074, China; (Y.L.); (M.Q.); (X.W.); (G.Z.); (Z.Z.)
| | - Gaofeng Zhan
- Department of Anesthesiology, Hubei Key Laboratory of Geriatric Anesthesia and Perioperative Brain Health, Wuhan Clinical Research Center for Geriatric Anesthesia, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430074, China; (Y.L.); (M.Q.); (X.W.); (G.Z.); (Z.Z.)
| | - Zhiqiang Zhou
- Department of Anesthesiology, Hubei Key Laboratory of Geriatric Anesthesia and Perioperative Brain Health, Wuhan Clinical Research Center for Geriatric Anesthesia, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430074, China; (Y.L.); (M.Q.); (X.W.); (G.Z.); (Z.Z.)
| | - Xiaoxiao Luo
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Shiyong Li
- Department of Anesthesiology, Hubei Key Laboratory of Geriatric Anesthesia and Perioperative Brain Health, Wuhan Clinical Research Center for Geriatric Anesthesia, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430074, China; (Y.L.); (M.Q.); (X.W.); (G.Z.); (Z.Z.)
| |
Collapse
|
10
|
Sarker A, Suh M, Choi Y, Park JY, Lee YS, Lee DS. Intrathecal [ 64Cu]Cu-albumin PET reveals age-related decline of lymphatic drainage of cerebrospinal fluid. Sci Rep 2023; 13:12930. [PMID: 37558700 PMCID: PMC10412645 DOI: 10.1038/s41598-023-39903-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Accepted: 08/01/2023] [Indexed: 08/11/2023] Open
Abstract
Age-related cognitive decline is associated with dysfunctional lymphatic drainage of cerebrospinal fluid (CSF) through meningeal lymphatic vessels. In this study, intrathecal [64Cu]Cu-albumin positron emission tomography (PET) was applied in mice to evaluate lymphatic drainage of CSF and its variation with age. [64Cu]Cu-albumin PET was performed at multiple time points after intrathecal injection of [64Cu]Cu-albumin at an infusion rate of 700 nl/min in adult and aged mice (15-25 months old). CSF clearance and paravertebral lymph nodes were quantified after injection and during the stationary phase. Stationary phase of the next day followed the initial perturbed state by injection of 6 ul (1/7 of total CSF volume) and CSF clearance half-time from the subarachnoid space was 93.4 ± 19.7 and 123.3 ± 15.6 min in adult and aged mice (p = 0.01), respectively. While the % injected dose of CSF space were higher, the activity of the paravertebral lymph nodes were lower in the aged mice on the next day. [64Cu]Cu-albumin PET enabled us to quantify CSF-lymphatic drainage across all levels of brain spinal cords and to visualize and quantify lymph node activity due to CSF drainage. [64Cu]Cu-albumin PET revealed the age-related decrease of the lymphatic drainage of CSF due to this decreased drainage from the subarachnoid space, especially during the stationary phase, in aged mice.
Collapse
Affiliation(s)
- Azmal Sarker
- Department of Nuclear Medicine, College of Medicine, Seoul National University, Seoul, Korea
| | - Minseok Suh
- Department of Nuclear Medicine, College of Medicine, Seoul National University, Seoul, Korea.
- Department of Nuclear Medicine, Seoul National University Hospital, Seoul, Korea.
- Biomedical Research Center, Seoul National University Hospital, Seoul, Korea.
| | - Yoori Choi
- Department of Nuclear Medicine, Seoul National University Hospital, Seoul, Korea
- Biomedical Research Center, Seoul National University Hospital, Seoul, Korea
- Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul National University, Seoul, Korea
| | - Ji Yong Park
- Department of Nuclear Medicine, College of Medicine, Seoul National University, Seoul, Korea
- Department of Nuclear Medicine, Seoul National University Hospital, Seoul, Korea
| | - Yun-Sang Lee
- Department of Nuclear Medicine, College of Medicine, Seoul National University, Seoul, Korea
- Department of Nuclear Medicine, Seoul National University Hospital, Seoul, Korea
| | - Dong Soo Lee
- Department of Nuclear Medicine, College of Medicine, Seoul National University, Seoul, Korea.
- Department of Nuclear Medicine, Seoul National University Hospital, Seoul, Korea.
- Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul National University, Seoul, Korea.
- Medical Research Center, College of Medicine, Seoul National University, Seoul, Korea.
- Medical Science and Engineering, School of Convergence Science and Technology, Pohang University of Science and Technology (POSTECH), Pohang, Korea.
| |
Collapse
|
11
|
Wang Z, Song Z, Zhou C, Fang Y, Gu L, Yang W, Gao T, Si X, Liu Y, Chen Y, Guan X, Guo T, Wu J, Bai X, Zhang M, Zhang B, Pu J. Reduced coupling of global brain function and cerebrospinal fluid dynamics in Parkinson's disease. J Cereb Blood Flow Metab 2023; 43:1328-1339. [PMID: 36927139 PMCID: PMC10369155 DOI: 10.1177/0271678x231164337] [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: 08/13/2022] [Revised: 01/18/2023] [Accepted: 01/23/2023] [Indexed: 03/18/2023]
Abstract
Dysfunction of the glymphatic system, an intracranial clearance pathway that drains misfolded proteins, has been implicated in the onset of Parkinson's disease (PD). Recently, the coupling strength of global blood-oxygen-level-dependent (gBOLD) signals and cerebrospinal fluid (CSF) inflow dynamics have been suggested to be an indicator of glymphatic function. Using resting-state functional magnetic resonance imaging (MRI), we quantified gBOLD-CSF coupling strength as the cross-correlation between baseline gBOLD and CSF inflow signals to evaluate glymphatic function and its association with the clinical manifestations of PD. We found that gBOLD-CSF coupling in drug-naïve PD patients was significantly weaker than that in normal controls, but significantly stronger in patients less affected by sleep disturbances than in those more affected by sleep disturbances, based on the PD sleep scale. Furthermore, we collected longitudinal data from patients and found that baseline gBOLD-CSF coupling negatively correlated with the rate of change over time, but positively correlated with the rate of change in UPDRS-III scores. In conclusion, severe gBOLD-CSF decoupling in PD patients may reflect longitudinal motor impairment, thereby providing a potential marker of glymphatic dysfunction in PD.
Collapse
Affiliation(s)
- Zhiyun Wang
- Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, China
| | - Zhe Song
- Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, China
| | - Cheng Zhou
- Department of Radiology, Second Affiliated Hospital, School of Medicine, Zhejiang University, China
| | - Yi Fang
- Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, China
| | - Luyan Gu
- Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, China
| | - Wenyi Yang
- Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, China
| | - Ting Gao
- Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, China
| | - Xiaoli Si
- Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, China
| | - Yi Liu
- Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, China
| | - Ying Chen
- Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, China
| | - Xiaojun Guan
- Department of Radiology, Second Affiliated Hospital, School of Medicine, Zhejiang University, China
| | - Tao Guo
- Department of Radiology, Second Affiliated Hospital, School of Medicine, Zhejiang University, China
| | - Jingjing Wu
- Department of Radiology, Second Affiliated Hospital, School of Medicine, Zhejiang University, China
| | - Xueqing Bai
- Department of Radiology, Second Affiliated Hospital, School of Medicine, Zhejiang University, China
| | - Minming Zhang
- Department of Radiology, Second Affiliated Hospital, School of Medicine, Zhejiang University, China
| | - Baorong Zhang
- Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, China
| | - Jiali Pu
- Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, China
| |
Collapse
|
12
|
Edelbo BL, Andreassen SN, Steffensen AB, MacAulay N. Day-night fluctuations in choroid plexus transcriptomics and cerebrospinal fluid metabolomics. PNAS NEXUS 2023; 2:pgad262. [PMID: 37614671 PMCID: PMC10443925 DOI: 10.1093/pnasnexus/pgad262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 07/06/2023] [Accepted: 07/31/2023] [Indexed: 08/25/2023]
Abstract
The cerebrospinal fluid (CSF) provides mechanical protection for the brain and serves as a brain dispersion route for nutrients, hormones, and metabolic waste. The CSF secretion rate is elevated in the dark phase in both humans and rats, which could support the CSF flow along the paravascular spaces that may be implicated in waste clearance. The similar diurnal CSF dynamics pattern observed in the day-active human and the nocturnal rat suggests a circadian regulation of this physiological variable, rather than sleep itself. To obtain a catalog of potential molecular drivers that could provide the day-night-associated modulation of the CSF secretion rate, we determined the diurnal fluctuation in the rat choroid plexus transcriptomic profile with RNA-seq and in the CSF metabolomics with ultraperformance liquid chromatography combined with mass spectrometry. We detected significant fluctuation of 19 CSF metabolites and differential expression of 2,778 choroid plexus genes between the light and the dark phase, the latter of which encompassed circadian rhythm-related genes and several choroid plexus transport mechanisms. The fluctuating components were organized with joint pathway analysis, of which several pathways demonstrated diurnal regulation. Our results illustrate substantial transcriptional and metabolic light-dark phase-mediated changes taking place in the rat choroid plexus and its encircling CSF. The combined data provide directions toward future identification of the molecular pathways governing the fluctuation of this physiological process and could potentially be harnessed to modulate the CSF dynamics in pathology.
Collapse
Affiliation(s)
| | | | | | - Nanna MacAulay
- Department of Neuroscience, University of Copenhagen, 2200 Copenhagen, Denmark
| |
Collapse
|
13
|
Que M, Li Y, Wang X, Zhan G, Luo X, Zhou Z. Role of astrocytes in sleep deprivation: accomplices, resisters, or bystanders? Front Cell Neurosci 2023; 17:1188306. [PMID: 37435045 PMCID: PMC10330732 DOI: 10.3389/fncel.2023.1188306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 06/05/2023] [Indexed: 07/13/2023] Open
Abstract
Sleep plays an essential role in all studied animals with a nervous system. However, sleep deprivation leads to various pathological changes and neurobehavioral problems. Astrocytes are the most abundant cells in the brain and are involved in various important functions, including neurotransmitter and ion homeostasis, synaptic and neuronal modulation, and blood-brain barrier maintenance; furthermore, they are associated with numerous neurodegenerative diseases, pain, and mood disorders. Moreover, astrocytes are increasingly being recognized as vital contributors to the regulation of sleep-wake cycles, both locally and in specific neural circuits. In this review, we begin by describing the role of astrocytes in regulating sleep and circadian rhythms, focusing on: (i) neuronal activity; (ii) metabolism; (iii) the glymphatic system; (iv) neuroinflammation; and (v) astrocyte-microglia cross-talk. Moreover, we review the role of astrocytes in sleep deprivation comorbidities and sleep deprivation-related brain disorders. Finally, we discuss potential interventions targeting astrocytes to prevent or treat sleep deprivation-related brain disorders. Pursuing these questions would pave the way for a deeper understanding of the cellular and neural mechanisms underlying sleep deprivation-comorbid brain disorders.
Collapse
Affiliation(s)
- Mengxin Que
- Hubei Key Laboratory of Geriatric Anesthesia and Perioperative Brain Health, Department of Anesthesiology, Tongji Medical College, Wuhan Clinical Research Center for Geriatric Anesthesia, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, China
| | - Yujuan Li
- Hubei Key Laboratory of Geriatric Anesthesia and Perioperative Brain Health, Department of Anesthesiology, Tongji Medical College, Wuhan Clinical Research Center for Geriatric Anesthesia, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, China
| | - Xuan Wang
- Hubei Key Laboratory of Geriatric Anesthesia and Perioperative Brain Health, Department of Anesthesiology, Tongji Medical College, Wuhan Clinical Research Center for Geriatric Anesthesia, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, China
| | - Gaofeng Zhan
- Hubei Key Laboratory of Geriatric Anesthesia and Perioperative Brain Health, Department of Anesthesiology, Tongji Medical College, Wuhan Clinical Research Center for Geriatric Anesthesia, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaoxiao Luo
- Department of Oncology, Tongji Medical College, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, China
| | - Zhiqiang Zhou
- Hubei Key Laboratory of Geriatric Anesthesia and Perioperative Brain Health, Department of Anesthesiology, Tongji Medical College, Wuhan Clinical Research Center for Geriatric Anesthesia, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, China
| |
Collapse
|
14
|
Morrone CD, Raghuraman R, Hussaini SA, Yu WH. Proteostasis failure exacerbates neuronal circuit dysfunction and sleep impairments in Alzheimer's disease. Mol Neurodegener 2023; 18:27. [PMID: 37085942 PMCID: PMC10119020 DOI: 10.1186/s13024-023-00617-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 03/29/2023] [Indexed: 04/23/2023] Open
Abstract
Failed proteostasis is a well-documented feature of Alzheimer's disease, particularly, reduced protein degradation and clearance. However, the contribution of failed proteostasis to neuronal circuit dysfunction is an emerging concept in neurodegenerative research and will prove critical in understanding cognitive decline. Our objective is to convey Alzheimer's disease progression with the growing evidence for a bidirectional relationship of sleep disruption and proteostasis failure. Proteostasis dysfunction and tauopathy in Alzheimer's disease disrupts neurons that regulate the sleep-wake cycle, which presents behavior as impaired slow wave and rapid eye movement sleep patterns. Subsequent sleep loss further impairs protein clearance. Sleep loss is a defined feature seen early in many neurodegenerative disorders and contributes to memory impairments in Alzheimer's disease. Canonical pathological hallmarks, β-amyloid, and tau, directly disrupt sleep, and neurodegeneration of locus coeruleus, hippocampal and hypothalamic neurons from tau proteinopathy causes disruption of the neuronal circuitry of sleep. Acting in a positive-feedback-loop, sleep loss and circadian rhythm disruption then increase spread of β-amyloid and tau, through impairments of proteasome, autophagy, unfolded protein response and glymphatic clearance. This phenomenon extends beyond β-amyloid and tau, with interactions of sleep impairment with the homeostasis of TDP-43, α-synuclein, FUS, and huntingtin proteins, implicating sleep loss as an important consideration in an array of neurodegenerative diseases and in cases of mixed neuropathology. Critically, the dynamics of this interaction in the neurodegenerative environment are not fully elucidated and are deserving of further discussion and research. Finally, we propose sleep-enhancing therapeutics as potential interventions for promoting healthy proteostasis, including β-amyloid and tau clearance, mechanistically linking these processes. With further clinical and preclinical research, we propose this dynamic interaction as a diagnostic and therapeutic framework, informing precise single- and combinatorial-treatments for Alzheimer's disease and other brain disorders.
Collapse
Affiliation(s)
- Christopher Daniel Morrone
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, 250 College St., Toronto, ON, M5T 1R8, Canada.
| | - Radha Raghuraman
- Taub Institute, Columbia University Irving Medical Center, 630W 168th Street, New York, NY, 10032, USA
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, 630W 168th Street, New York, NY, 10032, USA
| | - S Abid Hussaini
- Taub Institute, Columbia University Irving Medical Center, 630W 168th Street, New York, NY, 10032, USA.
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, 630W 168th Street, New York, NY, 10032, USA.
| | - Wai Haung Yu
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, 250 College St., Toronto, ON, M5T 1R8, Canada.
- Geriatric Mental Health Research Services, Centre for Addiction and Mental Health, 250 College St., Toronto, ON, M5T 1R8, Canada.
- Department of Pharmacology and Toxicology, University of Toronto, Medical Sciences Building, 1 King's College Circle, Toronto, ON, M5S 1A8, Canada.
| |
Collapse
|
15
|
Song AK, Hett K, Eisma JJ, McKnight CD, Elenberger J, Stark AJ, Kang H, Yan Y, Considine CM, Donahue MJ, Claassen DO. Parasagittal dural space hypertrophy and amyloid-β deposition in Alzheimer's disease. Brain Commun 2023; 5:fcad128. [PMID: 37143860 PMCID: PMC10152899 DOI: 10.1093/braincomms/fcad128] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 03/08/2023] [Accepted: 04/14/2023] [Indexed: 05/06/2023] Open
Abstract
One of the pathological hallmarks of Alzheimer's and related diseases is the increased accumulation of protein amyloid-β in the brain parenchyma. As such, recent studies have focused on characterizing protein and related clearance pathways involving perivascular flow of neurofluids, but human studies of these pathways are limited owing to limited methods for evaluating neurofluid circulation non-invasively in vivo. Here, we utilize non-invasive MRI methods to explore surrogate measures of CSF production, bulk flow and egress in the context of independent PET measures of amyloid-β accumulation in older adults. Participants (N = 23) were scanned at 3.0 T with 3D T2-weighted turbo spin echo, 2D perfusion-weighted pseudo-continuous arterial spin labelling and phase-contrast angiography to quantify parasagittal dural space volume, choroid plexus perfusion and net CSF flow through the aqueduct of Sylvius, respectively. All participants also underwent dynamic PET imaging with amyloid-β tracer 11C-Pittsburgh Compound B to quantify global cerebral amyloid-β accumulation. Spearman's correlation analyses revealed a significant relationship between global amyloid-β accumulation and parasagittal dural space volume (rho = 0.529, P = 0.010), specifically in the frontal (rho = 0.527, P = 0.010) and parietal (rho = 0.616, P = 0.002) subsegments. No relationships were observed between amyloid-β and choroid plexus perfusion nor net CSF flow. Findings suggest that parasagittal dural space hypertrophy, and its possible role in CSF-mediated clearance, may be closely related to global amyloid-β accumulation. These findings are discussed in the context of our growing understanding of the physiological mechanisms of amyloid-β aggregation and clearance via neurofluids.
Collapse
Affiliation(s)
- Alexander K Song
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37232, USA
| | - Kilian Hett
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Jarrod J Eisma
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Colin D McKnight
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Jason Elenberger
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Adam J Stark
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Hakmook Kang
- Department of Biostatistics, Vanderbilt University Medical Center, Nashville, TN 32732, USA
- Center for Quantitative Sciences, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Yan Yan
- Department of Biostatistics, Vanderbilt University Medical Center, Nashville, TN 32732, USA
| | - Ciaran M Considine
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Manus J Donahue
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37232, USA
| | - Daniel O Claassen
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| |
Collapse
|
16
|
Cerasuolo M, Papa M, Colangelo AM, Rizzo MR. Alzheimer’s Disease from the Amyloidogenic Theory to the Puzzling Crossroads between Vascular, Metabolic and Energetic Maladaptive Plasticity. Biomedicines 2023; 11:biomedicines11030861. [PMID: 36979840 PMCID: PMC10045635 DOI: 10.3390/biomedicines11030861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Revised: 03/06/2023] [Accepted: 03/09/2023] [Indexed: 03/16/2023] Open
Abstract
Alzheimer’s disease (AD) is a progressive and degenerative disease producing the most common type of dementia worldwide. The main pathogenetic hypothesis in recent decades has been the well-known amyloidogenic hypothesis based on the involvement of two proteins in AD pathogenesis: amyloid β (Aβ) and tau. Amyloid deposition reported in all AD patients is nowadays considered an independent risk factor for cognitive decline. Vascular damage and blood–brain barrier (BBB) failure in AD is considered a pivotal mechanism for brain injury, with increased deposition of both immunoglobulins and fibrin. Furthermore, BBB dysfunction could be an early sign of cognitive decline and the early stages of clinical AD. Vascular damage generates hypoperfusion and relative hypoxia in areas with high energy demand. Long-term hypoxia and the accumulation within the brain parenchyma of neurotoxic molecules could be seeds of a self-sustaining pathological progression. Cellular dysfunction comprises all the elements of the neurovascular unit (NVU) and neuronal loss, which could be the result of energy failure and mitochondrial impairment. Brain glucose metabolism is compromised, showing a specific region distribution. This energy deficit worsens throughout aging. Mild cognitive impairment has been reported to be associated with a glucose deficit in the entorhinal cortex and in the parietal lobes. The current aim is to understand the complex interactions between amyloid β (Aβ) and tau and elements of the BBB and NVU in the brain. This new approach aimed at the study of metabolic mechanisms and energy insufficiency due to mitochondrial impairment would allow us to define therapies aimed at predicting and slowing down the progression of AD.
Collapse
Affiliation(s)
- Michele Cerasuolo
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy
| | - Michele Papa
- Laboratory of Neuronal Networks Morphology and System Biology, Department of Mental and Physical Health and Preventive Medicine, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy
- SYSBIO Centre of Systems Biology ISBE-IT, 20126 Milan, Italy
- Correspondence:
| | - Anna Maria Colangelo
- SYSBIO Centre of Systems Biology ISBE-IT, 20126 Milan, Italy
- Laboratory of Neuroscience “R. Levi-Montalcini”, Department of Biotechnology and Biosciences, NeuroMI Milan Center for Neuroscience, University of Milano-Bicocca, 20126 Milano, Italy
| | - Maria Rosaria Rizzo
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy
| |
Collapse
|
17
|
Kodam P, Sai Swaroop R, Pradhan SS, Sivaramakrishnan V, Vadrevu R. Integrated multi-omics analysis of Alzheimer's disease shows molecular signatures associated with disease progression and potential therapeutic targets. Sci Rep 2023; 13:3695. [PMID: 36879094 PMCID: PMC9986671 DOI: 10.1038/s41598-023-30892-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 03/02/2023] [Indexed: 03/08/2023] Open
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by the formation of amyloid plaques implicated in neuronal death. Genetics, age, and sex are the risk factors attributed to AD. Though omics studies have helped to identify pathways associated with AD, an integrated systems analysis with the available data could help to understand mechanisms, potential biomarkers, and therapeutic targets. Analysis of transcriptomic data sets from the GEO database, and proteomic and metabolomic data sets from literature was performed to identify deregulated pathways and commonality analysis identified overlapping pathways among the data sets. The deregulated pathways included those of neurotransmitter synapses, oxidative stress, inflammation, vitamins, complement, and coagulation pathways. Cell type analysis of GEO data sets showed microglia, endothelial, myeloid, and lymphoid cells are affected. Microglia are associated with inflammation and pruning of synapses with implications for memory and cognition. Analysis of the protein-cofactor network of B2, B6, and pantothenate shows metabolic pathways modulated by these vitamins which overlap with the deregulated pathways from the multi-omics analysis. Overall, the integrated analysis identified the molecular signature associated with AD. Treatment with anti-oxidants, B2, B6, and pantothenate in genetically susceptible individuals in the pre-symptomatic stage might help in better management of the disease.
Collapse
Affiliation(s)
- Pradeep Kodam
- Department of Biological Sciences, Birla Institute of Technology and Science Pilani, Hyderabad Campus, Jawahar Nagar, Hyderabad, Telangana, 500078, India
| | - R Sai Swaroop
- Disease Biology Lab, Department of Biosciences, Sri Sathya Sai Institute of Higher Learning, Prasanthi Nilayam, Anantapur, Andhra Pradesh, 515134, India
| | - Sai Sanwid Pradhan
- Disease Biology Lab, Department of Biosciences, Sri Sathya Sai Institute of Higher Learning, Prasanthi Nilayam, Anantapur, Andhra Pradesh, 515134, India
| | - Venketesh Sivaramakrishnan
- Disease Biology Lab, Department of Biosciences, Sri Sathya Sai Institute of Higher Learning, Prasanthi Nilayam, Anantapur, Andhra Pradesh, 515134, India.
| | - Ramakrishna Vadrevu
- Department of Biological Sciences, Birla Institute of Technology and Science Pilani, Hyderabad Campus, Jawahar Nagar, Hyderabad, Telangana, 500078, India.
| |
Collapse
|
18
|
Chu Y, Hirst WD, Kordower JH. Mixed pathology as a rule, not exception: Time to reconsider disease nosology. HANDBOOK OF CLINICAL NEUROLOGY 2023; 192:57-71. [PMID: 36796948 DOI: 10.1016/b978-0-323-85538-9.00012-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Parkinson's disease is a progressive neurodegenerative disorder that is associated with motor and nonmotor symptoms. Accumulation of misfolded α-synuclein is considered a key pathological feature during disease initiation and progression. While clearly deemed a synucleinopathy, the development of amyloid-β plaques, tau-containing neurofibrillary tangles, and even TDP-43 protein inclusions occur within the nigrostriatal system and in other brain regions. In addition, inflammatory responses, manifested by glial reactivity, T-cell infiltration, and increased expression of inflammatory cytokines, plus other toxic mediators derived from activated glial cells, are currently recognized as prominent drivers of Parkinson's disease pathology. However, copathologies have increasingly been recognized as the rule (>90%) and not the exception, with Parkinson's disease cases on average exhibiting three different copathologies. While microinfarcts, atherosclerosis, arteriolosclerosis, and cerebral amyloid angiopathy may have an impact on disease progression, α-synuclein, amyloid-β, and TDP-43 pathology do not seem to contribute to progression.
Collapse
Affiliation(s)
- Yaping Chu
- ASU-Banner Neurodegenerative Disease Research Center, Arizona State University, Tempe, AZ, United States
| | - Warren D Hirst
- Neurodegenerative Diseases Research Unit, Biogen, Boston, MA, United States
| | - Jeffrey H Kordower
- ASU-Banner Neurodegenerative Disease Research Center, Arizona State University, Tempe, AZ, United States.
| |
Collapse
|
19
|
Whole CNS 3D Cryo-Fluorescence Tomography Shows CSF Clearance along Nasal Lymphatics, Spinal Nerves, and Lumbar/Sacral Lymph Nodes. J Imaging 2023; 9:jimaging9020045. [PMID: 36826964 PMCID: PMC9960470 DOI: 10.3390/jimaging9020045] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 02/11/2023] [Accepted: 02/13/2023] [Indexed: 02/18/2023] Open
Abstract
Unwanted proteins and metabolic waste in cerebral spinal fluid are cleared from the brain by meningeal and nasal lymphatics and the perineural sheath of cranial nerves; however, the distribution and clearance of cerebral spinal fluid (CSF) along the subarachnoid space of the entire spinal cord is not fully understood. Cryo-fluorescence tomography (CFT) was used to follow the movement of tracers from the ventricular system of the brain down through the meningeal lining of the spinal cord and out to the spinal lymphatic nodes. Isoflurane-anesthetized mice were infused into the lateral cerebroventricle with 5.0 µL of quantum dots [QdotR 605 ITKTM amino (PEG)] over two mins. Mice were allowed to recover (ca 2-3 min) and remained awake and ambulatory for 5, 15, 30, 60, and 120 min after which they were euthanized, and the entire intact body was frozen at -80°. The entire mouse was sectioned, and white light and fluorescent images were captured after each slice to produce high resolution three-dimensional volumes. Tracer appeared throughout the ventricular system and central canal of the spinal cord and the entire subarachnoid space of the CNS. A signal could be visualized in the nasal cavity, deep cervical lymph nodes, thoracic lymph nodes, and more superficial submandibular lymph nodes as early as 15 min post infusion. A fluorescent signal could be visualized along the dorsal root ganglia and down the proximal extension of the spinal nerves of the thoracic and lumbar segments at 30 min. There was a significant accumulation of tracer in the lumbar and sacral lymph nodes between 15-60 min. The dense fluorescent signal in the thoracic vertebrae noted at 5- and 15-min post infusion was significantly reduced by 30 min. Indeed, all signals in the spinal cord were ostensibly absent by 120 min, except for trace amounts in the coccyx. The brain still had some residual signal at 120 min. These data show that Qdots with a hydrodynamic diameter of 16-20 nm rapidly clear from the brain of awake mice. These data also clearly demonstrate the rapid distribution and efflux of traces along a major length of the vertebral column and the potential contribution of the spinal cord in the clearance of brain waste.
Collapse
|
20
|
Brain Waste Removal System and Sleep: Photobiomodulation as an Innovative Strategy for Night Therapy of Brain Diseases. Int J Mol Sci 2023; 24:ijms24043221. [PMID: 36834631 PMCID: PMC9965491 DOI: 10.3390/ijms24043221] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 01/28/2023] [Accepted: 02/02/2023] [Indexed: 02/10/2023] Open
Abstract
Emerging evidence suggests that an important function of the sleeping brain is the removal of wastes and toxins from the central nervous system (CNS) due to the activation of the brain waste removal system (BWRS). The meningeal lymphatic vessels (MLVs) are an important part of the BWRS. A decrease in MLV function is associated with Alzheimer's and Parkinson's diseases, intracranial hemorrhages, brain tumors and trauma. Since the BWRS is activated during sleep, a new idea is now being actively discussed in the scientific community: night stimulation of the BWRS might be an innovative and promising strategy for neurorehabilitation medicine. This review highlights new trends in photobiomodulation of the BWRS/MLVs during deep sleep as a breakthrough technology for the effective removal of wastes and unnecessary compounds from the brain in order to increase the neuroprotection of the CNS as well as to prevent or delay various brain diseases.
Collapse
|
21
|
van der Thiel MM, Backes WH, Ramakers IHGB, Jansen JFA. Novel developments in non-contrast enhanced MRI of the perivascular clearance system: What are the possibilities for Alzheimer's disease research? Neurosci Biobehav Rev 2023; 144:104999. [PMID: 36529311 DOI: 10.1016/j.neubiorev.2022.104999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 11/21/2022] [Accepted: 12/10/2022] [Indexed: 12/23/2022]
Abstract
The cerebral waste clearance system (i.e, glymphatic or intramural periarterial drainage) works through a network of perivascular spaces (PVS). Dysfunction of this system likely contributes to aggregation of Amyloid-β and subsequent toxic plaques in Alzheimer's disease (AD). A promising, non-invasive technique to study this system is MRI, though applications in dementia are still scarce. This review focusses on recent non-contrast enhanced (non-CE) MRI techniques which determine and visualise physiological aspects of the clearance system at multiple levels, i.e., cerebrospinal fluid flow, PVS-flow and interstitial fluid movement. Furthermore, various MRI studies focussing on aspects of the clearance system which are relevant to AD are discussed, such as studies on ageing, sleep alterations, and cognitive decline. Additionally, the complementary function of non-CE to CE methods is elaborated upon. We conclude that non-CE studies have great potential to determine which parts of the waste clearance system are affected by AD and in which stages of cognitive impairment dysfunction of this system occurs, which could allow future clinical trials to target these specific mechanisms.
Collapse
Affiliation(s)
- Merel M van der Thiel
- Department of Radiology & Nuclear Medicine, Maastricht University Medical Center, Maastricht, the Netherlands; Department of Psychiatry &Neuropsychology, Maastricht University, Maastricht, the Netherlands; School for Mental Health & Neuroscience, Maastricht University, Maastricht, the Netherlands
| | - Walter H Backes
- Department of Radiology & Nuclear Medicine, Maastricht University Medical Center, Maastricht, the Netherlands; School for Mental Health & Neuroscience, Maastricht University, Maastricht, the Netherlands; School for Cardiovascular Disease, Maastricht University, Maastricht, the Netherlands
| | - Inez H G B Ramakers
- Department of Psychiatry &Neuropsychology, Maastricht University, Maastricht, the Netherlands; School for Mental Health & Neuroscience, Maastricht University, Maastricht, the Netherlands
| | - Jacobus F A Jansen
- Department of Radiology & Nuclear Medicine, Maastricht University Medical Center, Maastricht, the Netherlands; School for Mental Health & Neuroscience, Maastricht University, Maastricht, the Netherlands; Department of Electrical Engineering, Eindhoven University of Technology, Eindhoven, the Netherlands.
| |
Collapse
|
22
|
Bohr T, Hjorth PG, Holst SC, Hrabětová S, Kiviniemi V, Lilius T, Lundgaard I, Mardal KA, Martens EA, Mori Y, Nägerl UV, Nicholson C, Tannenbaum A, Thomas JH, Tithof J, Benveniste H, Iliff JJ, Kelley DH, Nedergaard M. The glymphatic system: Current understanding and modeling. iScience 2022; 25:104987. [PMID: 36093063 PMCID: PMC9460186 DOI: 10.1016/j.isci.2022.104987] [Citation(s) in RCA: 88] [Impact Index Per Article: 44.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
We review theoretical and numerical models of the glymphatic system, which circulates cerebrospinal fluid and interstitial fluid around the brain, facilitating solute transport. Models enable hypothesis development and predictions of transport, with clinical applications including drug delivery, stroke, cardiac arrest, and neurodegenerative disorders like Alzheimer's disease. We sort existing models into broad categories by anatomical function: Perivascular flow, transport in brain parenchyma, interfaces to perivascular spaces, efflux routes, and links to neuronal activity. Needs and opportunities for future work are highlighted wherever possible; new models, expanded models, and novel experiments to inform models could all have tremendous value for advancing the field.
Collapse
Affiliation(s)
- Tomas Bohr
- Department of Physics, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Poul G. Hjorth
- Department of Applied Mathematics and Computer Science, Technical University of Denmark, Richard Petersens Plads, 2800 Kgs. Lyngby, Denmark
| | - Sebastian C. Holst
- Neuroscience and Rare Diseases Discovery and Translational Area, Roche Pharmaceutical Research and Early Development, Roche Innovation Center Basel, Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - Sabina Hrabětová
- Department of Cell Biology and The Robert Furchgott Center for Neural and Behavioral Science, State University of New York Downstate Medical Center, Brooklyn, NY, USA
| | - Vesa Kiviniemi
- Oulu Functional NeuroImaging, Department of Diagnostic Radiology, MRC, Oulu University Hospital, Oulu, Finland
- Medical Imaging, Physics and Technology, the Faculty of Medicine, University of Oulu, Oulu, Finland
| | - Tuomas Lilius
- Department of Pharmacology, Faculty of Medicine, University of Helsinki, Helsinki, Finland
- Individualized Drug Therapy Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
- Center for Translational Neuromedicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Emergency Medicine and Services, Helsinki University Hospital and University of Helsinki, Helsinki, Finland
| | - Iben Lundgaard
- Department of Experimental Medical Science, Lund University, Lund, Sweden
- Wallenberg Centre for Molecular Medicine, Lund University, Lund, Sweden
| | - Kent-Andre Mardal
- Department of Mathematics, University of Oslo, Oslo, Norway
- Simula Research Laboratory, Department of Numerical Analysis and Scientific Computing, Oslo, Norway
| | | | - Yuki Mori
- Center for Translational Neuromedicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - U. Valentin Nägerl
- Instítut Interdisciplinaire de Neurosciences, Université de Bordeaux / CNRS UMR 5297, Centre Broca Nouvelle-Aquitaine, 146 rue Léo Saignat, CS 61292 Case 130, 33076 Bordeaux Cedex France
| | - Charles Nicholson
- Department of Neuroscience and Physiology, New York University Grossman School of Medicine, New York, NY, USA
- Department of Cell Biology, SUNY Downstate Health Sciences University, Brooklyn, NY, USA
| | - Allen Tannenbaum
- Departments of Computer Science/ Applied Mathematics and Statistics, Stony Brook University, Stony Brook, NY, USA
| | - John H. Thomas
- Department of Mechanical Engineering, University of Rochester, Rochester, 14627 NY, USA
| | - Jeffrey Tithof
- Department of Mechanical Engineering, University of Minnesota, Minneapolis, USA
| | - Helene Benveniste
- Department of Anesthesiology, Yale School of Medicine, New Haven, CT, USA
- Department of Biomedical Engineering, Yale School of Medicine, New Haven, CT, USA
| | - Jeffrey J. Iliff
- VISN 20 Mental Illness Research, Education and Clinical Center, VA Puget Sound Health Care System, Seattle, WA, USA
- Department of Psychiatry and Behavioral Sciences, University of Washington School of Medicine, Seattle, WA, USA
- Department of Neurology, University of Washington School of Medicine, Seattle, WA, USA
| | - Douglas H. Kelley
- Department of Mechanical Engineering, University of Rochester, Rochester, 14627 NY, USA
| | - Maiken Nedergaard
- Center for Translational Neuromedicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Center for Translational Neuromedicine, University of Rochester Medical Center, Rochester, 14642 NY, USA
| |
Collapse
|
23
|
Li G, Cao Y, Tang X, Huang J, Cai L, Zhou L. The meningeal lymphatic vessels and the glymphatic system: Potential therapeutic targets in neurological disorders. J Cereb Blood Flow Metab 2022; 42:1364-1382. [PMID: 35484910 PMCID: PMC9274866 DOI: 10.1177/0271678x221098145] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 04/03/2022] [Accepted: 04/14/2022] [Indexed: 02/05/2023]
Abstract
The recent discovery of the meningeal lymphatic vessels (mLVs) and glymphatic pathways has challenged the long-lasting dogma that the central nervous system (CNS) lacks a lymphatic system and therefore does not interact with peripheral immunity. This discovery has reshaped our understanding of mechanisms underlying CNS drainage. Under normal conditions, a close connection between mLVs and the glymphatic system enables metabolic waste removal, immune cell trafficking, and CNS immune surveillance. Dysfunction of the glymphatic-mLV system can lead to toxic protein accumulation in the brain, and it contributes to the development of a series of neurodegenerative disorders, such as Alzheimer's and Parkinson's diseases. The identification of precise cerebral transport routes is based mainly on indirect, invasive imaging of animals, and the results cannot always be applied to humans. Here we review the functions of the glymphatic-mLV system and evidence for its involvement in some CNS diseases. We focus on emerging noninvasive imaging techniques to evaluate the human glymphatic-mLV system and their potential for preclinical diagnosis and prevention of neurodegenerative diseases. Potential strategies that target the glymphatic-mLV system in order to treat and prevent neurological disorders are also discussed.
Collapse
Affiliation(s)
- Gaowei Li
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, China
| | - Yi Cao
- Department of Neurosurgery, Chengdu Second People's hospital, Chengdu, China
| | - Xin Tang
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, China
| | - Jianhan Huang
- Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China
| | - Linjun Cai
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, China
| | - Liangxue Zhou
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, China
| |
Collapse
|
24
|
Dvořáková L, Stenroos P, Paasonen E, Salo RA, Paasonen J, Gröhn O. Light sedation with short habituation time for large-scale functional magnetic resonance imaging studies in rats. NMR IN BIOMEDICINE 2022; 35:e4679. [PMID: 34961988 PMCID: PMC9285600 DOI: 10.1002/nbm.4679] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 12/14/2021] [Accepted: 12/15/2021] [Indexed: 06/14/2023]
Abstract
Traditionally, preclinical resting state functional magnetic resonance imaging (fMRI) studies have been performed in anesthetized animals. Nevertheless, as anesthesia affects the functional connectivity (FC) in the brain, there has been a growing interest in imaging in the awake state. Obviously, awake imaging requires resource- and time-consuming habituation prior to data acquisition to reduce the stress and motion of the animals. Light sedation has been a less widely exploited alternative for awake imaging, requiring shorter habituation times, while still reducing the effect of anesthesia. Here, we imaged 102 rats under light sedation and 10 awake animals to conduct an FC analysis. We established an automated data-processing pipeline suitable for both groups. Additionally, the same pipeline was used on data obtained from an openly available awake rat database (289 measurements in 90 rats). The FC pattern in the light sedation measurements closely resembled the corresponding patterns in both onsite and offsite awake datasets. However, fewer datasets had to be excluded due to movement in rats with light sedation. The temporal analysis of FC in the lightly sedated group indicated a lingering effect of anesthesia that stabilized after the first 5 min. In summary, our results indicate that the light sedation protocol is a valid alternative for large-scale studies where awake protocols may become prohibitively resource-demanding, as it provides similar results to awake imaging, preserves more scans, and requires shorter habituation times. The large amount of fMRI data obtained in this work are openly available for further analyses.
Collapse
Affiliation(s)
- Lenka Dvořáková
- A. I. V. Institute for Molecular SciencesUniversity of Eastern FinlandKuopioFinland
| | - Petteri Stenroos
- A. I. V. Institute for Molecular SciencesUniversity of Eastern FinlandKuopioFinland
- Grenoble Institut des NeurosciencesUniversité Grenoble AlpesGrenobleFrance
| | - Ekaterina Paasonen
- A. I. V. Institute for Molecular SciencesUniversity of Eastern FinlandKuopioFinland
| | - Raimo A. Salo
- A. I. V. Institute for Molecular SciencesUniversity of Eastern FinlandKuopioFinland
| | - Jaakko Paasonen
- A. I. V. Institute for Molecular SciencesUniversity of Eastern FinlandKuopioFinland
| | - Olli Gröhn
- A. I. V. Institute for Molecular SciencesUniversity of Eastern FinlandKuopioFinland
| |
Collapse
|
25
|
Yi T, Gao P, Zhu T, Yin H, Jin S. Glymphatic System Dysfunction: A Novel Mediator of Sleep Disorders and Headaches. Front Neurol 2022; 13:885020. [PMID: 35665055 PMCID: PMC9160458 DOI: 10.3389/fneur.2022.885020] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Accepted: 04/13/2022] [Indexed: 11/13/2022] Open
Abstract
Sleep contributes to the maintenance of overall health and well-being. There are a growing number of patients who have headache disorders that are significantly affected by poor sleep. This is a paradoxical relationship, whereby sleep deprivation or excess sleep leads to a worsening of headaches, yet sleep onset also alleviates ongoing headache pain. Currently, the mechanism of action remains controversial and poorly understood. The glymphatic system is a newly discovered perivascular network that encompasses the whole brain and is responsible for removing toxic proteins and waste metabolites from the brain as well as replenishing nutrition and energy. Recent studies have suggested that glymphatic dysfunction is a common underlying etiology of sleep disorders and headache pain. This study reviews the current literature on the relationship between the glymphatic system, sleep, and headaches, discusses their roles, and proposes acupuncture as a non-invasive way to focus on the glymphatic function to improve sleep quality and alleviate headache pain.
Collapse
Affiliation(s)
- Ting Yi
- Rehabilitation and Health Preservation School, Chengdu University of TCM, Chengdu, China
| | - Ping Gao
- Rehabilitation and Health Preservation School, Chengdu University of TCM, Chengdu, China
| | - Tianmin Zhu
- Rehabilitation and Health Preservation School, Chengdu University of TCM, Chengdu, China
- Tianmin Zhu
| | - Haiyan Yin
- School of Acupuncture and Tuina, Chengdu University of TCM, Chengdu, China
- *Correspondence: Haiyan Yin
| | - Shuoguo Jin
- Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, China
- Shuoguo Jin
| |
Collapse
|
26
|
Padmakumar S, Kulkarni P, Ferris CF, Bleier BS, Amiji MM. Traumatic brain injury and the development of parkinsonism: Understanding pathophysiology, animal models, and therapeutic targets. Biomed Pharmacother 2022; 149:112812. [PMID: 35290887 PMCID: PMC9050934 DOI: 10.1016/j.biopha.2022.112812] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 03/06/2022] [Accepted: 03/08/2022] [Indexed: 02/06/2023] Open
Abstract
The clinical translation of therapeutic approaches to combat debilitating neurodegenerative conditions, such as Parkinson's disease (PD), remains as an urgent unmet challenge. The strong molecular association between the pathogenesis of traumatic brain injury (TBI) and the development of parkinsonism in humans has been well established. Therefore, a lot of ongoing research aims to investigate this pathology overlap in-depth, to exploit the common targets of TBI and PD for development of more effective and long-term treatment strategies. This review article intends to provide a detailed background on TBI pathophysiology and its established overlap with PD with an additional emphasis on the recent findings about their effect on perivascular clearance. Although, the traditional animal models of TBI and PD are still being considered, there is a huge focus on the development of combinatory hybrid animal models coupling concussion with the pre-established PD models for a better recapitulation of the human context of PD pathogenesis. Lastly, the therapeutic targets for TBI and PD, and the contemporary research involving exosomes, DNA vaccines, miRNA, gene therapy and gene editing for the development of potential candidates are discussed, along with the recent development of lesser invasive and promising central nervous system (CNS) drug delivery strategies.
Collapse
Affiliation(s)
- Smrithi Padmakumar
- Department of Pharmaceutical Sciences, School of Pharmacy and Department of Chemical Engineering, College of Engineering, Northeastern University, Boston, MA, United States of America
| | - Praveen Kulkarni
- Center for Translational NeuroImaging, Northeastern University, Boston, MA, United States of America
| | - Craig F Ferris
- Center for Translational NeuroImaging, Northeastern University, Boston, MA, United States of America
| | - Benjamin S Bleier
- Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, United States of America
| | - Mansoor M Amiji
- Department of Pharmaceutical Sciences, School of Pharmacy and Department of Chemical Engineering, College of Engineering, Northeastern University, Boston, MA, United States of America.
| |
Collapse
|
27
|
Zhang D, Li X, Li B. Glymphatic System Dysfunction in Central Nervous System Diseases and Mood Disorders. Front Aging Neurosci 2022; 14:873697. [PMID: 35547631 PMCID: PMC9082304 DOI: 10.3389/fnagi.2022.873697] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 03/31/2022] [Indexed: 12/13/2022] Open
Abstract
The glymphatic system, a recently discovered macroscopic waste removal system in the brain, has many unknown aspects, especially its driving forces and relationship with sleep, and thus further explorations of the relationship between the glymphatic system and a variety of possible related diseases are urgently needed. Here, we focus on the progress in current research on the role of the glymphatic system in several common central nervous system diseases and mood disorders, discuss the structural and functional abnormalities of the glymphatic system which may occur before or during the pathophysiological progress and the possible underlying mechanisms. We emphasize the relationship between sleep and the glymphatic system under pathological conditions and summarize the common imaging techniques for the glymphatic system currently available. The perfection of the glymphatic system hypothesis and the exploration of the effects of aging and endocrine factors on the central and peripheral regulatory pathways through the glymphatic system still require exploration in the future.
Collapse
Affiliation(s)
- Dianjun Zhang
- Department of Forensic Analytical Toxicology, School of Forensic Medicine, China Medical University, Shenyang, China
- Liaoning Province Key Laboratory of Forensic Bio-evidence Sciences, School of Forensic Medicine, China Medical University, Shenyang, China
- China Medical University Center of Forensic Investigation, School of Forensic Medicine, China Medical University, Shenyang, China
| | - Xinyu Li
- Department of Forensic Analytical Toxicology, School of Forensic Medicine, China Medical University, Shenyang, China
- Liaoning Province Key Laboratory of Forensic Bio-evidence Sciences, School of Forensic Medicine, China Medical University, Shenyang, China
- China Medical University Center of Forensic Investigation, School of Forensic Medicine, China Medical University, Shenyang, China
| | - Baoman Li
- Department of Forensic Analytical Toxicology, School of Forensic Medicine, China Medical University, Shenyang, China
- Liaoning Province Key Laboratory of Forensic Bio-evidence Sciences, School of Forensic Medicine, China Medical University, Shenyang, China
- China Medical University Center of Forensic Investigation, School of Forensic Medicine, China Medical University, Shenyang, China
| |
Collapse
|
28
|
Ferris CF. Applications in Awake Animal Magnetic Resonance Imaging. Front Neurosci 2022; 16:854377. [PMID: 35450017 PMCID: PMC9017993 DOI: 10.3389/fnins.2022.854377] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 03/09/2022] [Indexed: 12/16/2022] Open
Abstract
There are numerous publications on methods and applications for awake functional MRI across different species, e.g., voles, rabbits, cats, dogs, and rhesus macaques. Each of these species, most obviously rhesus monkey, have general or unique attributes that provide a better understanding of the human condition. However, much of the work today is done on rodents. The growing number of small bore (≤30 cm) high field systems 7T- 11.7T favor the use of small animals. To that point, this review is primarily focused on rodents and their many applications in awake function MRI. Applications include, pharmacological MRI, drugs of abuse, sensory evoked stimuli, brain disorders, pain, social behavior, and fear.
Collapse
|
29
|
Abstract
The brain harbors a unique ability to, figuratively speaking, shift its gears. During wakefulness, the brain is geared fully toward processing information and behaving, while homeostatic functions predominate during sleep. The blood-brain barrier establishes a stable environment that is optimal for neuronal function, yet the barrier imposes a physiological problem; transcapillary filtration that forms extracellular fluid in other organs is reduced to a minimum in brain. Consequently, the brain depends on a special fluid [the cerebrospinal fluid (CSF)] that is flushed into brain along the unique perivascular spaces created by astrocytic vascular endfeet. We describe this pathway, coined the term glymphatic system, based on its dependency on astrocytic vascular endfeet and their adluminal expression of aquaporin-4 water channels facing toward CSF-filled perivascular spaces. Glymphatic clearance of potentially harmful metabolic or protein waste products, such as amyloid-β, is primarily active during sleep, when its physiological drivers, the cardiac cycle, respiration, and slow vasomotion, together efficiently propel CSF inflow along periarterial spaces. The brain's extracellular space contains an abundance of proteoglycans and hyaluronan, which provide a low-resistance hydraulic conduit that rapidly can expand and shrink during the sleep-wake cycle. We describe this unique fluid system of the brain, which meets the brain's requisites to maintain homeostasis similar to peripheral organs, considering the blood-brain-barrier and the paths for formation and egress of the CSF.
Collapse
Affiliation(s)
- Martin Kaag Rasmussen
- Center for Translational Neuromedicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Humberto Mestre
- Center for Translational Neuromedicine, University of Rochester Medical Center, Rochester, New York
| | - Maiken Nedergaard
- Center for Translational Neuromedicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Center for Translational Neuromedicine, University of Rochester Medical Center, Rochester, New York
| |
Collapse
|
30
|
Zamani A, Walker AK, Rollo B, Ayers KL, Farah R, O'Brien TJ, Wright DK. Impaired glymphatic function in the early stages of disease in a TDP-43 mouse model of amyotrophic lateral sclerosis. Transl Neurodegener 2022; 11:17. [PMID: 35287738 PMCID: PMC8922788 DOI: 10.1186/s40035-022-00291-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 02/17/2022] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Multiple lines of evidence suggest possible impairment of the glymphatic system in amyotrophic lateral sclerosis (ALS). To investigate this, we used in vivo magnetic resonance imaging (MRI) to assess glymphatic function early in the course of disease in a transgenic mouse with doxycycline (Dox)-controlled expression of cytoplasmic human TDP-43 (hTDP-43ΔNLS), mimicking the key pathology implicated in ALS. METHODS Adult TDP-43 transgenic and littermate monogenic control mice underwent longitudinal multimodal MRI one and three weeks after the cessation of Dox feed, together with weekly rotarod assessments of motor performance. Glymphatic function was assessed using dynamic contrast-enhanced MRI to track the clearance of an MR contrast agent injected into the cisterna magna. RESULTS Compared to their littermate controls, TDP-43 mice exhibited progressive neurodegeneration including that within the primary motor cortex, primary somatosensory cortex and corticospinal tract, significant weight loss including gastrocnemius atrophy, and shortened telomere length. Furthermore, in the presence of this ALS-like phenotype, these mice have significantly disrupted glymphatic function. CONCLUSIONS Although the relationship between glymphatic clearance and ALS disease progression remains to be elucidated, these changes occurred very early in the disease course. This provides initial evidence to suggest that the glymphatic system might be a potential therapeutic target in the treatment of ALS.
Collapse
Affiliation(s)
- Akram Zamani
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, 3004, Australia
| | - Adam K Walker
- Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Ben Rollo
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, 3004, Australia
| | - Katie L Ayers
- The Murdoch Children's Research Institute, The Royal Children's Hospital, Parkville, VIC, 3052, Australia.,Department of Pediatrics, The University of Melbourne, Parkville, VIC, 3052, Australia
| | - Raysha Farah
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, 3004, Australia
| | - Terence J O'Brien
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, 3004, Australia.,Department of Medicine, The Royal Melbourne Hospital, The University of Melbourne, Parkville, VIC, 3052, Australia
| | - David K Wright
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, 3004, Australia.
| |
Collapse
|
31
|
Wardlaw JM, Benveniste H, Williams A. Cerebral Vascular Dysfunctions Detected in Human Small Vessel Disease and Implications for Preclinical Studies. Annu Rev Physiol 2022; 84:409-434. [PMID: 34699267 DOI: 10.1146/annurev-physiol-060821-014521] [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] [Indexed: 11/09/2022]
Abstract
Cerebral small vessel disease (SVD) is highly prevalent and a common cause of ischemic and hemorrhagic stroke and dementia, yet the pathophysiology is poorly understood. Its clinical expression is highly varied, and prognostic implications are frequently overlooked in clinics; thus, treatment is currently confined to vascular risk factor management. Traditionally, SVD is considered the small vessel equivalent of large artery stroke (occlusion, rupture), but data emerging from human neuroimaging and genetic studies refute this, instead showing microvessel endothelial dysfunction impacting on cell-cell interactions and leading to brain damage. These dysfunctions reflect defects that appear to be inherited and secondary to environmental exposures, including vascular risk factors. Interrogation in preclinical models shows consistent and converging molecular and cellular interactions across the endothelial-glial-neural unit that increasingly explain the human macroscopic observations and identify common patterns of pathology despite different triggers. Importantly, these insights may offer new targets for therapeutic intervention focused on restoring endothelial-glial physiology.
Collapse
Affiliation(s)
- Joanna M Wardlaw
- Division of Neuroimaging Sciences, Centre for Clinical Brain Sciences; UK Dementia Research Institute; and Edinburgh Imaging, University of Edinburgh, Edinburgh, United Kingdom;
| | - Helene Benveniste
- Department of Anesthesiology, Yale School of Medicine, New Haven, Connecticut, USA
| | - Anna Williams
- Centre for Regenerative Medicine, Institute for Regeneration and Repair, University of Edinburgh, Edinburgh, United Kingdom
| |
Collapse
|
32
|
Leaston J, Kulkarni P, Gharagouzloo C, Qiao J, Bens N, Ferris CF. Do We Swallow the Waste From Our Brain? Front Neurosci 2021; 15:763780. [PMID: 34887724 PMCID: PMC8649892 DOI: 10.3389/fnins.2021.763780] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 10/22/2021] [Indexed: 11/13/2022] Open
Abstract
Ferumoxytol, an iron oxide nanoparticle, was infused into the lateral cerebroventricle of awake rats to follow its movement and clearance from the brain using magnetic resonance imaging. Within minutes the contrast agent could be observed accumulating in the subarachnoid space, nasal cavity, nasal pharynx, and soft palate at the back of the throat. In a subsequent study fluorescent quantum dots were infused into the brain of rats and within 15 min could be observed in the esophagus using microscopy. These imaging studies clearly show that these large nanoparticle tracers (∼20 nm in diameter) leave the brain through the nasal cavity and end up in the gut. There are numerous studies going back decades reporting the clearance of tracers put directly into the brain. While these studies show the slow accumulation of trace in the blood and lymphatics, they report only accounting for less than 50% of what was originally put in the brain.
Collapse
Affiliation(s)
| | - Praveen Kulkarni
- Center for Translational Neuroimaging, Northeastern University, Boston, MA, United States
| | - Codi Gharagouzloo
- Imaginostics, Inc., Cambridge, MA, United States.,Center for Translational Neuroimaging, Northeastern University, Boston, MA, United States
| | - Ju Qiao
- Center for Translational Neuroimaging, Northeastern University, Boston, MA, United States
| | - Nicole Bens
- Center for Translational Neuroimaging, Northeastern University, Boston, MA, United States
| | - Craig F Ferris
- Center for Translational Neuroimaging, Northeastern University, Boston, MA, United States
| |
Collapse
|
33
|
Cai X, Harding IC, Sadaka AH, Colarusso B, Kulkarni P, Ebong E, Qiao J, O'Hare NR, Ferris CF. Mild repetitive head impacts alter perivascular flow in the midbrain dopaminergic system in awake rats. Brain Commun 2021; 3:fcab265. [PMID: 34806002 PMCID: PMC8600963 DOI: 10.1093/braincomms/fcab265] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 08/02/2021] [Accepted: 08/10/2021] [Indexed: 11/24/2022] Open
Abstract
Head injury is a known risk factor for Parkinson's disease. Disruption in the perivascular clearance of metabolic waste and unwanted proteins is thought to be a contributing factor to disease progression. We hypothesized that repetitive mild head impacts, without evidence of structural brain damage, would increase microgliosis and AQP4 expression and depolarization and alter perivascular flow in the midbrain dopaminergic system. Adult male rats were subjected to sham, or two mild head impacts separated by 48 h. Three weeks later, fully awake rats were imaged using dynamic, contrast-enhanced MRI to follow the distribution of intraventricular gadobenate dimeglumine contrast agent. Images were registered to and analysed using a 3D MRI rat atlas providing site-specific data on 171 different brain areas. Following imaging, rats were tested for cognitive function using the Barnes maze assay. Histological analyses of tyrosine hydroxylase, microglia activation and AQP4 expression and polarization were performed on a parallel cohort of head impacted rats at 20 days post insult to coordinate with the time of imaging. There was no change in the global flux of contrast agent between sham and head impacted rats. The midbrain dopaminergic system showed a significant decrease in the influx of contrast agent as compared to sham controls together with a significant increase in microgliosis, AQP4 expression and depolarization. There were no deficits in cognitive function. The histology showed a significant level of neuroinflammation in the midbrain dopaminergic system 3 weeks post mild repetitive head impact but no loss in tyrosine hydroxylase. MRI revealed no structural brain damage emphasizing the potential serious consequences of mild head impacts on sustained brain neuroinflammation in this area critical to the pathophysiology of Parkinson's.
Collapse
Affiliation(s)
- Xuezhu Cai
- Department of Psychology, Center for Translational NeuroImaging, Northeastern University, Boston, MA 02115, USA
| | - Ian C Harding
- Department of Bioengineering, Northeastern University, Boston, MA 02115, USA
| | - Aymen H Sadaka
- Department of Psychology, Center for Translational NeuroImaging, Northeastern University, Boston, MA 02115, USA
| | - Bradley Colarusso
- Department of Psychology, Center for Translational NeuroImaging, Northeastern University, Boston, MA 02115, USA
| | - Praveen Kulkarni
- Department of Psychology, Center for Translational NeuroImaging, Northeastern University, Boston, MA 02115, USA
| | - Eno Ebong
- Department of Bioengineering, Northeastern University, Boston, MA 02115, USA
- Department of Chemical Engineering, Northeastern University, Boston, MA 02115, USA
- Department of Neuroscience, Albert Einstein College of Medicine, New York, NY 10461, USA
| | - Ju Qiao
- Department of Psychology, Center for Translational NeuroImaging, Northeastern University, Boston, MA 02115, USA
| | - Nick R O'Hare
- Department of Bioengineering, Northeastern University, Boston, MA 02115, USA
| | - Craig F Ferris
- Department of Psychology, Center for Translational NeuroImaging, Northeastern University, Boston, MA 02115, USA
- Department of Psychology, Northeastern University, Boston, MA 02115, USA
- Department of Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, USA
| |
Collapse
|
34
|
Abstract
Sleep is essential for brain function in a surprisingly diverse set of ways. In the short term, lack of sleep leads to impaired memory and attention; in the longer term, it produces neurological dysfunction or even death. I discuss recent advances in understanding how sleep maintains the physiological health of the brain through interconnected systems of neuronal activity and fluid flow. The neural dynamics that appear during sleep are intrinsically coupled to its consequences for blood flow, cerebrospinal fluid dynamics, and waste clearance. Recognizing these linked causes and consequences of sleep has shed new light on why sleep is important for such disparate aspects of brain function.
Collapse
Affiliation(s)
- Laura D Lewis
- Department of Biomedical Engineering, Boston University, Boston, MA, USA, and Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, MA, USA
| |
Collapse
|
35
|
Brain Renin-Angiotensin System as Novel and Potential Therapeutic Target for Alzheimer's Disease. Int J Mol Sci 2021; 22:ijms221810139. [PMID: 34576302 PMCID: PMC8468637 DOI: 10.3390/ijms221810139] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 09/12/2021] [Accepted: 09/14/2021] [Indexed: 12/15/2022] Open
Abstract
The activation of the brain renin-angiotensin system (RAS) plays a pivotal role in the pathophysiology of cognition. While the brain RAS has been studied before in the context of hypertension, little is known about its role and regulation in relation to neuronal function and its modulation. Adequate blood flow to the brain as well as proper clearing of metabolic byproducts become crucial in the presence of neurodegenerative disorders such as Alzheimer's disease (AD). RAS inhibition (RASi) drugs that can cross into the central nervous system have yielded unclear results in improving cognition in AD patients. Consequently, only one RASi therapy is under consideration in clinical trials to modify AD. Moreover, the role of non-genetic factors such as hypercholesterolemia in the pathophysiology of AD remains largely uncharacterized, even when evidence exists that it can lead to alteration of the RAS and cognition in animal models. Here we revise the evidence for the function of the brain RAS in cognition and AD pathogenesis and summarize the evidence that links it to hypercholesterolemia and other risk factors. We review existent medications for RASi therapy and show research on novel drugs, including small molecules and nanodelivery strategies that can target the brain RAS with potential high specificity. We hope that further research into the brain RAS function and modulation will lead to innovative therapies that can finally improve AD neurodegeneration.
Collapse
|
36
|
Yousef Yengej DN, Ferando I, Kechechyan G, Nwaobi SE, Raman S, Charles A, Faas GC. Continuous long-term recording and triggering of brain neurovascular activity and behaviour in freely moving rodents. J Physiol 2021; 599:4545-4559. [PMID: 34438476 DOI: 10.1113/jp281514] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 08/23/2021] [Indexed: 11/08/2022] Open
Abstract
A minimally invasive, microchip-based approach enables continuous long-term recording of brain neurovascular activity, heart rate, and head movement in freely behaving rodents. This approach can also be used for transcranial optical triggering of cortical activity in mice expressing channelrhodopsin. The system uses optical intrinsic signal recording to measure cerebral blood volume, which under baseline conditions is correlated with spontaneous neuronal activity. The arterial pulse and breathing can be quantified as a component of the optical intrinsic signal. Multi-directional head movement is measured simultaneously with a movement sensor. A separate movement tracking element through a camera enables precise mapping of overall movement within an enclosure. Data is processed by a dedicated single board computer, and streamed from multiple enclosures to a central server, enabling simultaneous remote monitoring and triggering in many subjects. One application of this system described here is the characterization of changes in of cerebral blood volume, heart rate and behaviour that occur with the sleep-wake cycle over weeks. Another application is optical triggering and recording of cortical spreading depression (CSD), the slowly propagated wave of neurovascular activity that occurs in the setting of brain injury and migraine aura. The neurovascular features of CSD are remarkably different in the awake vs. anaesthetized state in the same mouse. With its capacity to continuously and synchronously record multiple types of physiological and behavioural data over extended time periods in combination with intermittent triggering of brain activity, this inexpensive method has the potential for widespread practical application in rodent research. KEY POINTS: Recording and triggering of brain activity in mice and rats has typically required breaching the skull, and experiments are often performed under anaesthesia A minimally invasive microchip system enables continuous recording and triggering of neurovascular activity, and analysis of heart rate and behaviour in freely behaving rodents over weeks This system can be used to characterize physiological and behavioural changes associated with the sleep-wake cycle over extended time periods This approach can also be used with mice expressing channelrhodopsin to trigger and record cortical spreading depression (CSD) in freely behaving subjects. The neurovascular responses to CSD are remarkably different under anaesthesia compared with the awake state. The method is inexpensive and straightforward to employ at a relatively large scale. It enables translational investigation of a wide range of physiological and pathological conditions in rodent models of neurological and systemic diseases.
Collapse
Affiliation(s)
- Dmitri N Yousef Yengej
- Department of Neurology, The David Geffen School of Medicine at UCLA, 635 Charles Young Drive South, Los Angeles, CA, 90095-733522, USA
| | - Isabella Ferando
- Department of Neurology, The David Geffen School of Medicine at UCLA, 635 Charles Young Drive South, Los Angeles, CA, 90095-733522, USA.,Department of Neurology, Miller School of Medicine at the University of Miami, 1150 NW 14th street, Miami, FL, 33136, USA
| | - Gayane Kechechyan
- Department of Neurology, The David Geffen School of Medicine at UCLA, 635 Charles Young Drive South, Los Angeles, CA, 90095-733522, USA.,University of California, San Diego, Skaggs School of Pharmacy and Pharmaceutical Sciences, 9500 Gilman Drive, MC 0657, La Jolla, CA, 92093-0657, USA
| | - Sinifunanya E Nwaobi
- Department of Neurology, The David Geffen School of Medicine at UCLA, 635 Charles Young Drive South, Los Angeles, CA, 90095-733522, USA
| | - Shrayes Raman
- School of Letters and Sciences, UCLA, 1309 Murphy Hall Box 951413, Los Angeles, CA, 90095-1413, USA
| | - Andrew Charles
- Department of Neurology, The David Geffen School of Medicine at UCLA, 635 Charles Young Drive South, Los Angeles, CA, 90095-733522, USA
| | - Guido C Faas
- Department of Neurology, The David Geffen School of Medicine at UCLA, 635 Charles Young Drive South, Los Angeles, CA, 90095-733522, USA
| |
Collapse
|
37
|
Eltanahy AM, Koluib YA, Gonzales A. Pericytes: Intrinsic Transportation Engineers of the CNS Microcirculation. Front Physiol 2021; 12:719701. [PMID: 34497540 PMCID: PMC8421025 DOI: 10.3389/fphys.2021.719701] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 07/29/2021] [Indexed: 12/15/2022] Open
Abstract
Pericytes in the brain are candidate regulators of microcirculatory blood flow because they are strategically positioned along the microvasculature, contain contractile proteins, respond rapidly to neuronal activation, and synchronize microvascular dynamics and neurovascular coupling within the capillary network. Analyses of mice with defects in pericyte generation demonstrate that pericytes are necessary for the formation of the blood-brain barrier, development of the glymphatic system, immune homeostasis, and white matter function. The development, identity, specialization, and progeny of different subtypes of pericytes, however, remain unclear. Pericytes perform brain-wide 'transportation engineering' functions in the capillary network, instructing, integrating, and coordinating signals within the cellular communicome in the neurovascular unit to efficiently distribute oxygen and nutrients ('goods and services') throughout the microvasculature ('transportation grid'). In this review, we identify emerging challenges in pericyte biology and shed light on potential pericyte-targeted therapeutic strategies.
Collapse
Affiliation(s)
- Ahmed M. Eltanahy
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, United States
| | - Yara A. Koluib
- Tanta University Hospitals, Faculty of Medicine, Tanta University, Tanta, Egypt
| | - Albert Gonzales
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, United States
| |
Collapse
|
38
|
Glymphatic clearance function in patients with cerebral small vessel disease. Neuroimage 2021; 238:118257. [PMID: 34118396 DOI: 10.1016/j.neuroimage.2021.118257] [Citation(s) in RCA: 138] [Impact Index Per Article: 46.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 05/31/2021] [Accepted: 06/07/2021] [Indexed: 02/08/2023] Open
Abstract
Few studies have focused on the connection between glymphatic dysfunction and cerebral small vessel disease (CSVD), partially due to the lack of non-invasive methods to measure glymphatic function. We established modified index for diffusion tensor image analysis along the perivascular space (mALPS-index), which was calculated on diffusion tensor image (DTI), compared it with the classical detection of glymphatic clearance function calculated on Glymphatic MRI after intrathecal administration of gadolinium (study 1), and analyzed the relationship between CSVD imaging markers and mALPS-index in CSVD patients from the CIRCLE study (ClinicalTrials.gov ID: NCT03542734) (study 2). Among 39 patients included in study 1, mALPS-index were significantly related to glymphatic clearance function calculated on Glymphatic MRI ( r = -0.772~-0.844, p < 0.001). A total of 330 CSVD patients were included in study 2. Severer periventricular and deep white matter hyperintensities (β = -0.332, p < 0.001; β = -0.293, p < 0.001), number of lacunas (β = -0.215, p < 0.001), number of microbleeds (β = -0.152, p = 0.005), and severer enlarged perivascular spaces in basal ganglia (β = -0.223, p < 0.001) were related to mALPS-index. Our results indicated that non-invasive mALPS-index might represent glymphatic clearance function, which could be applied in clinic in future. Glymphatic clearance function might play a role in the development of CSVD.
Collapse
|
39
|
Naseri Kouzehgarani G, Feldsien T, Engelhard HH, Mirakhur KK, Phipps C, Nimmrich V, Clausznitzer D, Lefebvre DR. Harnessing cerebrospinal fluid circulation for drug delivery to brain tissues. Adv Drug Deliv Rev 2021; 173:20-59. [PMID: 33705875 DOI: 10.1016/j.addr.2021.03.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 02/10/2021] [Accepted: 03/01/2021] [Indexed: 12/31/2022]
Abstract
Initially thought to be useful only to reach tissues in the immediate vicinity of the CSF circulatory system, CSF circulation is now increasingly viewed as a viable pathway to deliver certain therapeutics deeper into brain tissues. There is emerging evidence that this goal is achievable in the case of large therapeutic proteins, provided conditions are met that are described herein. We show how fluid dynamic modeling helps predict infusion rate and duration to overcome high CSF turnover. We posit that despite model limitations and controversies, fluid dynamic models, pharmacokinetic models, preclinical testing, and a qualitative understanding of the glymphatic system circulation can be used to estimate drug penetration in brain tissues. Lastly, in addition to highlighting landmark scientific and medical literature, we provide practical advice on formulation development, device selection, and pharmacokinetic modeling. Our review of clinical studies suggests a growing interest for intra-CSF delivery, particularly for targeted proteins.
Collapse
|
40
|
Ferris CF. Rethinking the Conditions and Mechanism for Glymphatic Clearance. Front Neurosci 2021; 15:624690. [PMID: 33897347 PMCID: PMC8060639 DOI: 10.3389/fnins.2021.624690] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Accepted: 03/10/2021] [Indexed: 11/13/2022] Open
Abstract
Critical studies that form the foundation of the glymphatic system and the clearance of metabolic by-products of unwanted proteins from the brain are reviewed. Concerns are raised about studying glymphatic flow in anesthetized animals and making assumptions about the whole brain based upon data collected from a cranial window on the cortex. A new model is proposed arguing that the flow of cerebral spinal fluid and parenchymal clearance in the perivascular system of unwanted proteins is regulated by circadian changes in brain temperature and blood flow at the level of the microvasculature.
Collapse
Affiliation(s)
- Craig F Ferris
- Department Psychology and Pharmaceutical Sciences, Center for Translational Neuroimaging, Northeastern University, Boston, MA, United States
| |
Collapse
|
41
|
Stanton EH, Persson NDÅ, Gomolka RS, Lilius T, Sigurðsson B, Lee H, Xavier ALR, Benveniste H, Nedergaard M, Mori Y. Mapping of CSF transport using high spatiotemporal resolution dynamic contrast-enhanced MRI in mice: Effect of anesthesia. Magn Reson Med 2021; 85:3326-3342. [PMID: 33426699 DOI: 10.1002/mrm.28645] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 11/23/2020] [Accepted: 11/23/2020] [Indexed: 12/31/2022]
Abstract
PURPOSE Dynamic contrast-enhanced MRI (DCE-MRI) represents the only available approach for glymphatic cerebrospinal fluid (CSF) flow 3D mapping in the brain of living animals and humans. The purpose of this study was to develop a novel DCE-MRI protocol for mapping of the glymphatic system transport with improved spatiotemporal resolution, and to validate the new protocol by comparing the transport in mice anesthetized with either isoflurane or ketamine/xylazine. METHODS The contrast agent, gadobutrol, was administered into the CSF of the cisterna magna and its transport visualized continuously on a 9.4T preclinical scanner using 3D fast-imaging with a steady-state free-precession sequence (3D-FISP), which has a spatial resolution of 0.001 mm3 and a temporal resolution of 30 s. The MR signals were measured dynamically for 60 min in multiple volumes of interest covering the entire CSF space and brain parenchyma. RESULTS The results confirm earlier findings that glymphatic CSF influx is higher under ketamine/xylazine than with isoflurane anesthesia. This was extended to account for new details about the distinct CSF efflux pathways under the two anesthetic regimens. Dynamic contrast MR shows that CSF clearance occurs mainly along the vagus nerve near the jugular vein under isoflurane and via the olfactory bulb under ketamine/xylazine. CONCLUSION The improved spatial and temporal sampling rates afforded by 3D-FISP shed new light on the pharmacological modulation of CSF efflux paths. The present observations may have the potential to set a new standard for future experimental DCE-MRI studies of the glymphatic system.
Collapse
Affiliation(s)
- Evan Hunter Stanton
- Center for Translational Neuromedicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Niklas Daniel Åke Persson
- Center for Translational Neuromedicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Ryszard Stefan Gomolka
- Center for Translational Neuromedicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Tuomas Lilius
- Center for Translational Neuromedicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Björn Sigurðsson
- Center for Translational Neuromedicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Hedok Lee
- Department of Anesthesiology, Yale School of Medicine, New Haven, Connecticut, USA
| | - Anna Lenice Ribeiro Xavier
- Center for Translational Neuromedicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Helene Benveniste
- Department of Anesthesiology, Yale School of Medicine, New Haven, Connecticut, USA
| | - Maiken Nedergaard
- Center for Translational Neuromedicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Center for Translational Neuromedicine, Department of Neurosurgery, University of Rochester Medical Center, Rochester, New York, USA
| | - Yuki Mori
- Center for Translational Neuromedicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| |
Collapse
|
42
|
Toriello M, González-Quintanilla V, Pascual J. [The glymphatic system and its involvement in disorders of the nervous system]. Med Clin (Barc) 2021; 156:339-343. [PMID: 33423825 DOI: 10.1016/j.medcli.2020.08.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 08/04/2020] [Accepted: 08/05/2020] [Indexed: 10/22/2022]
Abstract
The central nervous system was thought to be devoid of lymphatics. Recently, the existence of an authentic brain lymphatic system, known as the glymphatic system, composed of paravascular channels penetrating arterial and venous brain vessels and dural lymphatics cleaning the interstitial space, has been demonstrated. Aquaporin-4, located in astrocyte feet attached to the paravascular spaces, plays a key role in the clearance of waste molecules, such as beta-amyloid or tau proteins. The activity of this system is increased during sleep, mainly in the slow wave phase and while sleeping on one side, and with exercise, and is reduced with aging. Even though data are still preliminary, the glymphatic system could be decisively involved in the pathophysiology of neurological disorders such as neurodegenerative and demyelinating diseases, normal pressure hydrocephalus, stroke or certain headaches. The discovery of this system should provide new opportunities for the treatment of these neurological disorders.
Collapse
Affiliation(s)
- María Toriello
- Servicio de Neurología, Hospital Universitario Marqués de Valdecilla, Universidad de Cantabria e IDIVAL, Santander, España
| | - Vicente González-Quintanilla
- Servicio de Neurología, Hospital Universitario Marqués de Valdecilla, Universidad de Cantabria e IDIVAL, Santander, España
| | - Julio Pascual
- Servicio de Neurología, Hospital Universitario Marqués de Valdecilla, Universidad de Cantabria e IDIVAL, Santander, España.
| |
Collapse
|
43
|
Ozturk BO, Monte B, Koundal S, Dai F, Benveniste H, Lee H. Disparate volumetric fluid shifts across cerebral tissue compartments with two different anesthetics. Fluids Barriers CNS 2021; 18:1. [PMID: 33407650 PMCID: PMC7788828 DOI: 10.1186/s12987-020-00236-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 12/15/2020] [Indexed: 02/08/2023] Open
Abstract
Background Large differences in glymphatic system transport—similar in magnitude to those of the sleep/wake cycle—have been observed during anesthesia with dexmedetomidine supplemented with low dose isoflurane (DEXM-I) in comparison to isoflurane (ISO). However, the biophysical and bioenergetic tissue status underlying glymphatic transport differences between anesthetics remains undefined. To further understand biophysical characteristics underlying these differences we investigated volume status across cerebral tissue compartments, water diffusivity, and T2* values in rats anesthetized with DEXM-I in comparison to ISO. Methods Using a crossover study design, a group of 12 Sprague Dawley female rats underwent repetitive magnetic resonance imaging (MRI) under ISO and DEXM-I. Physiological parameters were continuously measured. MRI included a proton density weighted (PDW) scan to investigate cerebrospinal fluid (CSF) and parenchymal volumetric changes, a multigradient echo scan (MGE) to calculate T2* maps as a measure of ‘bioenergetics’, and a diffusion scan to quantify the apparent diffusion coefficient (ADC). Results The heart rate was lower with DEXM-I in comparison to ISO, but all other physiological variables were similar across scans and groups. The PDW images revealed a 1% parenchymal volume increase with ISO compared to DEXM-I comprising multiple focal tissue areas scattered across the forebrain. In contrast, with DEXM-I the CSF compartment was enlarged by ~ 6% in comparison to ISO at the level of the basal cisterns and peri-arterial conduits which are main CSF influx routes for glymphatic transport. The T2* maps showed brain-wide increases in T2* in ISO compared to DEXM-I rats. Diffusion-weighted images yielded no significant differences in ADCs across the two anesthesia groups. Conclusions We demonstrated CSF volume expansion with DEXM-I (in comparison to ISO) and parenchymal (GM) expansion with ISO (in comparison to DEXM-I), which may explain the differences in glymphatic transport. The T2* changes in ISO are suggestive of an increased bioenergetic state associated with excess cellular firing/bursting when compared to DEXM-I.
Collapse
Affiliation(s)
- Burhan O Ozturk
- Department of Anesthesiology, Yale School of Medicine, 330 Cedar Street, New Haven, CT, USA
| | - Brittany Monte
- Department of Anesthesiology, Yale School of Medicine, 330 Cedar Street, New Haven, CT, USA
| | - Sunil Koundal
- Department of Anesthesiology, Yale School of Medicine, 330 Cedar Street, New Haven, CT, USA
| | - Feng Dai
- Yale Center for Analytical Sciences, Yale School of Public Health, New Haven, CT, USA
| | - Helene Benveniste
- Department of Anesthesiology, Yale School of Medicine, 330 Cedar Street, New Haven, CT, USA. .,Department of Biomedical Engineering, Yale School of Medicine, New Haven, CT, USA.
| | - Hedok Lee
- Department of Anesthesiology, Yale School of Medicine, 330 Cedar Street, New Haven, CT, USA
| |
Collapse
|
44
|
Yan T, Qiu Y, Yu X, Yang L. Glymphatic Dysfunction: A Bridge Between Sleep Disturbance and Mood Disorders. Front Psychiatry 2021; 12:658340. [PMID: 34025481 PMCID: PMC8138157 DOI: 10.3389/fpsyt.2021.658340] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 04/12/2021] [Indexed: 12/14/2022] Open
Abstract
Mounting evidence demonstrates a close relationship between sleep disturbance and mood disorders, including major depression disorder (MDD) and bipolar disorder (BD). According to the classical two-process model of sleep regulation, circadian rhythms driven by the light-dark cycle, and sleep homeostasis modulated by the sleep-wake cycle are disrupted in mood disorders. However, the exact mechanism of interaction between sleep and mood disorders remains unclear. Recent discovery of the glymphatic system and its dynamic fluctuation with sleep provide a plausible explanation. The diurnal variation of the glymphatic circulation is dependent on the astrocytic activity and polarization of water channel protein aquaporin-4 (AQP4). Both animal and human studies have reported suppressed glymphatic transport, abnormal astrocytes, and depolarized AQP4 in mood disorders. In this study, the "glymphatic dysfunction" hypothesis which suggests that the dysfunctional glymphatic pathway serves as a bridge between sleep disturbance and mood disorders is proposed.
Collapse
Affiliation(s)
- Tao Yan
- Department of Psychiatry, Changxing People's Hospital, Huzhou, China
| | - Yuefeng Qiu
- Department of Psychiatry, Zhejiang Hospital, Hangzhou, China
| | - Xinfeng Yu
- Department of Radiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Linglin Yang
- Department of Psychiatry, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| |
Collapse
|
45
|
Direct Measurement of Cerebrospinal Fluid Production in Mice. Cell Rep 2020; 33:108524. [PMID: 33357428 PMCID: PMC8186543 DOI: 10.1016/j.celrep.2020.108524] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 08/12/2020] [Accepted: 11/23/2020] [Indexed: 11/23/2022] Open
Abstract
The emerging interest in brain fluid transport has prompted a need for techniques that provide an understanding of what factors regulate cerebrospinal fluid (CSF) production. Here, we describe a methodology for direct quantification of CSF production in awake mice. We measure CSF production by placing a catheter in a lateral ventricle, while physically blocking outflow from the 4th ventricle. Using this methodology, we show that CSF production increases during isoflurane anesthesia, and to a lesser extent with ketamine/xylazine anesthesia, relative to the awake state. Aged mice have reduced CSF production, which is even lower in aged mice overexpressing amyloid-β. Unexpectedly, CSF production in young female mice is 30% higher than in age-matched males. Altogether, the present observations imply that a reduction in CSF production might contribute to the age-related risk of proteinopathies but that the rate of CSF production and glymphatic fluid transport are not directly linked. Liu et al. develop a method for direct quantification of cerebrospinal fluid (CSF) production in awake mice. Using this method, the authors evaluate the effect of brain states, ages, sex, anesthetic types, and amyloid-β burden on CSF production.
Collapse
|
46
|
Benveniste H, Lee H, Ozturk B, Chen X, Koundal S, Vaska P, Tannenbaum A, Volkow ND. Glymphatic Cerebrospinal Fluid and Solute Transport Quantified by MRI and PET Imaging. Neuroscience 2020; 474:63-79. [PMID: 33248153 DOI: 10.1016/j.neuroscience.2020.11.014] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 11/04/2020] [Accepted: 11/07/2020] [Indexed: 12/13/2022]
Abstract
Over the past decade there has been an enormous progress in our understanding of fluid and solute transport in the central nervous system (CNS). This is due to a number of factors, including important developments in whole brain imaging technology and computational fluid dynamics analysis employed for the elucidation of glymphatic transport function in the live animal and human brain. In this paper, we review the technical aspects of dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) in combination with administration of Gd-based tracers into the cerebrospinal fluid (CSF) for tracking glymphatic solute and fluid transport in the CNS as well as lymphatic drainage. Used in conjunction with advanced computational processing methods including optimal mass transport analysis, one gains new insights into the biophysical forces governing solute transport in the CNS which leads to intriguing new research directions. Considering drainage pathways, we review the novel T1 mapping technique for quantifying glymphatic transport and cervical lymph node drainage concurrently in the same subject. We provide an overview of knowledge gleaned from DCE-MRI studies of glymphatic transport and meningeal lymphatic drainage. Finally, we introduce positron emission tomography (PET) and CSF administration of radiotracers as an alternative method to explore other pharmacokinetic aspects of CSF transport into brain parenchyma as well as efflux pathways.
Collapse
Affiliation(s)
- Helene Benveniste
- Department of Anesthesiology, Yale School of Medicine, New Haven, CT, United States; Department of Biomedical Engineering, Yale School of Medicine, New Haven, CT, United States.
| | - Hedok Lee
- Department of Anesthesiology, Yale School of Medicine, New Haven, CT, United States
| | - Burhan Ozturk
- Department of Anesthesiology, Yale School of Medicine, New Haven, CT, United States
| | - Xinan Chen
- Departments of Computer Science and Applied Mathematics & Statistics, Stony Brook University, Stony Brook, NY, United States
| | - Sunil Koundal
- Department of Anesthesiology, Yale School of Medicine, New Haven, CT, United States
| | - Paul Vaska
- Department of Radiology and Biomedical Engineering, Renaissance School of Medicine at Stony Brook University, Stony Brook, NY, United States
| | - Allen Tannenbaum
- Departments of Computer Science and Applied Mathematics & Statistics, Stony Brook University, Stony Brook, NY, United States
| | - Nora D Volkow
- Laboratory for Neuroimaging, NIAAA, Bethesda, MD, United States
| |
Collapse
|
47
|
Xue Y, Liu X, Koundal S, Constantinou S, Dai F, Santambrogio L, Lee H, Benveniste H. In vivo T1 mapping for quantifying glymphatic system transport and cervical lymph node drainage. Sci Rep 2020; 10:14592. [PMID: 32884041 PMCID: PMC7471332 DOI: 10.1038/s41598-020-71582-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Accepted: 07/24/2020] [Indexed: 12/13/2022] Open
Abstract
Dynamic contrast-enhanced magnetic resonance imaging (MRI) for tracking glymphatic system transport with paramagnetic contrast such as gadoteric acid (Gd-DOTA) administration into cerebrospinal fluid (CSF) requires pre-contrast data for proper quantification. Here we introduce an alternative approach for glymphatic system quantification in the mouse brain via T1 mapping which also captures drainage of Gd-DOTA to the cervical lymph nodes. The Gd-DOTA injection into CSF was performed on the bench after which the mice underwent T1 mapping using a 3D spoiled gradient echo sequence on a 9.4 T MRI. In Ketamine/Xylazine (KX) anesthetized mice, glymphatic transport and drainage of Gd-DOTA to submandibular and deep cervical lymph nodes was demonstrated as 25–50% T1 reductions in comparison to control mice receiving CSF saline. To further validate the T1 mapping approach we also verified increased glymphatic transport of Gd-DOTA transport in mice anesthetized with KX in comparison with ISO. The novel T1 mapping method allows for quantification of glymphatic transport as well as drainage to the deep and superficial cervical lymph nodes. The ability to measure glymphatic transport and cervical lymph node drainage in the same animal longitudinally is advantageous and time efficient and the coupling between the two systems can be studied and translated to human studies.
Collapse
Affiliation(s)
- Yuechuan Xue
- Department of Anesthesiology, Yale School of Medicine, 330 Cedar St, TMP 3, New Haven, CT, 06520, USA.,Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China
| | - Xiaodan Liu
- Department of Anesthesiology, Yale School of Medicine, 330 Cedar St, TMP 3, New Haven, CT, 06520, USA
| | - Sunil Koundal
- Department of Anesthesiology, Yale School of Medicine, 330 Cedar St, TMP 3, New Haven, CT, 06520, USA
| | - Stefan Constantinou
- Department of Anesthesiology, Yale School of Medicine, 330 Cedar St, TMP 3, New Haven, CT, 06520, USA
| | - Feng Dai
- Yale Center for Analytical Sciences, Yale School of Public Health, New Haven, CT, USA
| | - Laura Santambrogio
- Englander Institute of Precision Medicine, Department of Radiation Oncology, Physiology and Biophysics, Weill Cornell Medicine, New York, NY, 10065, USA
| | - Hedok Lee
- Department of Anesthesiology, Yale School of Medicine, 330 Cedar St, TMP 3, New Haven, CT, 06520, USA
| | - Helene Benveniste
- Department of Anesthesiology, Yale School of Medicine, 330 Cedar St, TMP 3, New Haven, CT, 06520, USA.
| |
Collapse
|
48
|
Hablitz LM, Plá V, Giannetto M, Vinitsky HS, Stæger FF, Metcalfe T, Nguyen R, Benrais A, Nedergaard M. Circadian control of brain glymphatic and lymphatic fluid flow. Nat Commun 2020; 11:4411. [PMID: 32879313 PMCID: PMC7468152 DOI: 10.1038/s41467-020-18115-2] [Citation(s) in RCA: 284] [Impact Index Per Article: 71.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2019] [Accepted: 07/24/2020] [Indexed: 12/20/2022] Open
Abstract
The glymphatic system is a network of perivascular spaces that promotes movement of cerebrospinal fluid (CSF) into the brain and clearance of metabolic waste. This fluid transport system is supported by the water channel aquaporin-4 (AQP4) localized to vascular endfeet of astrocytes. The glymphatic system is more effective during sleep, but whether sleep timing promotes glymphatic function remains unknown. We here show glymphatic influx and clearance exhibit endogenous, circadian rhythms peaking during the mid-rest phase of mice. Drainage of CSF from the cisterna magna to the lymph nodes exhibits daily variation opposite to glymphatic influx, suggesting distribution of CSF throughout the animal depends on time-of-day. The perivascular polarization of AQP4 is highest during the rest phase and loss of AQP4 eliminates the day-night difference in both glymphatic influx and drainage to the lymph nodes. We conclude that CSF distribution is under circadian control and that AQP4 supports this rhythm.
Collapse
Affiliation(s)
- Lauren M Hablitz
- Center for Translational Neuromedicine, University of Rochester Medical Center, Rochester, NY, 14642, USA.
| | - Virginia Plá
- Center for Translational Neuromedicine, University of Rochester Medical Center, Rochester, NY, 14642, USA
| | - Michael Giannetto
- Center for Translational Neuromedicine, University of Rochester Medical Center, Rochester, NY, 14642, USA
| | - Hanna S Vinitsky
- Center for Translational Neuromedicine, University of Rochester Medical Center, Rochester, NY, 14642, USA
| | - Frederik Filip Stæger
- Center for Basic and Translational Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Tanner Metcalfe
- Center for Translational Neuromedicine, University of Rochester Medical Center, Rochester, NY, 14642, USA
| | - Rebecca Nguyen
- Center for Translational Neuromedicine, University of Rochester Medical Center, Rochester, NY, 14642, USA
| | - Abdellatif Benrais
- Center for Translational Neuromedicine, University of Rochester Medical Center, Rochester, NY, 14642, USA
| | - Maiken Nedergaard
- Center for Translational Neuromedicine, University of Rochester Medical Center, Rochester, NY, 14642, USA.
- Center for Basic and Translational Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark.
| |
Collapse
|
49
|
Brain Glymphatic/Lymphatic Imaging by MRI and PET. Nucl Med Mol Imaging 2020; 54:207-223. [PMID: 33088350 DOI: 10.1007/s13139-020-00665-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 08/09/2020] [Accepted: 08/19/2020] [Indexed: 01/19/2023] Open
Abstract
Since glymphatic was proposed and meningeal lymphatic was discovered, MRI and even PET were introduced to investigate brain parenchymal interstitial fluid (ISF), cerebrospinal fluid (CSF), and lymphatic outflow in rodents and humans. Previous findings by ex vivo fluorescent microscopic, and in vivo two-photon imaging in rodents were reproduced using intrathecal contrast (gadobutrol and the similar)-enhanced MRI in rodents and further in humans. On dynamic MRI of meningeal lymphatics, in contrast to rodents, humans use mainly dorsal meningeal lymphatic pathways of ISF-CSF-lymphatic efflux. In mice, ISF-CSF exchange was examined thoroughly using an intra-cistern injection of fluorescent tracers during sleep, aging, and neurodegeneration yielding many details. CSF to lymphatic efflux is across arachnoid barrier cells over the dorsal dura in rodents and in humans. Meningeal lymphatic efflux to cervical lymph nodes and systemic circulation is also well-delineated especially in humans onintrathecal contrast MRI. Sleep- or anesthesia-related changes of glymphatic-lymphatic flow and the coupling of ISF-CSF-lymphatic drainage are major confounders ininterpreting brain glymphatic/lymphatic outflow in rodents. PET imaging in humans should be interpreted based on human anatomy and physiology, different in some aspects, using MRI recently. Based on the summary in this review, we propose non-invasive and longer-term intrathecal SPECT/PET or MRI studies to unravel the roles of brain glymphatic/lymphatic in diseases.
Collapse
|
50
|
Mestre H, Mori Y, Nedergaard M. The Brain's Glymphatic System: Current Controversies. Trends Neurosci 2020; 43:458-466. [PMID: 32423764 DOI: 10.1016/j.tins.2020.04.003] [Citation(s) in RCA: 271] [Impact Index Per Article: 67.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 03/16/2020] [Accepted: 04/09/2020] [Indexed: 12/14/2022]
Abstract
The glymphatic concept along with the discovery of meningeal lymphatic vessels have, in recent years, highlighted that fluid is directionally transported within the central nervous system (CNS). Imaging studies, as well as manipulations of fluid transport, point to a key role of the glymphatic-lymphatic system in clearance of amyloid-β and other proteins. As such, the glymphatic-lymphatic system represents a new target in combating neurodegenerative diseases. Not unexpectedly, introduction of a new plumbing system in the brain has stirred controversies. This opinion article will highlight what we know about the brain's fluid transport systems, where experimental data are lacking, and what is still debated.
Collapse
Affiliation(s)
- Humberto Mestre
- Center for Translational Neuromedicine, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Yuki Mori
- Center for Translational Neuromedicine, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Maiken Nedergaard
- Center for Translational Neuromedicine, University of Rochester Medical Center, Rochester, NY 14642, USA; Center for Translational Neuromedicine, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark.
| |
Collapse
|