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King NE, Courtney JM, Brown LS, Fortune AJ, Blackburn NB, Fletcher JL, Cashion JM, Talbot J, Pébay A, Hewitt AW, Morris GP, Young KM, Cook AL, Sutherland BA. Induced pluripotent stem cell derived pericytes respond to mediators of proliferation and contractility. Stem Cell Res Ther 2024; 15:59. [PMID: 38433209 PMCID: PMC10910734 DOI: 10.1186/s13287-024-03671-x] [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: 10/18/2023] [Accepted: 02/16/2024] [Indexed: 03/05/2024] Open
Abstract
BACKGROUND Pericytes are multifunctional contractile cells that reside on capillaries. Pericytes are critical regulators of cerebral blood flow and blood-brain barrier function, and pericyte dysfunction may contribute to the pathophysiology of human neurological diseases including Alzheimers disease, multiple sclerosis, and stroke. Induced pluripotent stem cell (iPSC)-derived pericytes (iPericytes) are a promising tool for vascular research. However, it is unclear how iPericytes functionally compare to primary human brain vascular pericytes (HBVPs). METHODS We differentiated iPSCs into iPericytes of either the mesoderm or neural crest lineage using established protocols. We compared iPericyte and HBVP morphologies, quantified gene expression by qPCR and bulk RNA sequencing, and visualised pericyte protein markers by immunocytochemistry. To determine whether the gene expression of neural crest iPericytes, mesoderm iPericytes or HBVPs correlated with their functional characteristics in vitro, we quantified EdU incorporation following exposure to the key pericyte mitogen, platelet derived growth factor (PDGF)-BB and, contraction and relaxation in response to the vasoconstrictor endothelin-1 or vasodilator adenosine, respectively. RESULTS iPericytes were morphologically similar to HBVPs and expressed canonical pericyte markers. However, iPericytes had 1864 differentially expressed genes compared to HBVPs, while there were 797 genes differentially expressed between neural crest and mesoderm iPericytes. Consistent with the ability of HBVPs to respond to PDGF-BB signalling, PDGF-BB enhanced and a PDGF receptor-beta inhibitor impaired iPericyte proliferation. Administration of endothelin-1 led to iPericyte contraction and adenosine led to iPericyte relaxation, of a magnitude similar to the response evoked in HBVPs. We determined that neural crest iPericytes were less susceptible to PDGFR beta inhibition, but responded most robustly to vasoconstrictive mediators. CONCLUSIONS iPericytes express pericyte-associated genes and proteins and, exhibit an appropriate physiological response upon exposure to a key endogenous mitogen or vasoactive mediators. Therefore, the generation of functional iPericytes would be suitable for use in future investigations exploring pericyte function or dysfunction in neurological diseases.
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Affiliation(s)
- Natalie E King
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Level 4, Medical Sciences Precinct, 17 Liverpool St, Hobart, TAS, 7000, Australia
| | - Jo-Maree Courtney
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Level 4, Medical Sciences Precinct, 17 Liverpool St, Hobart, TAS, 7000, Australia
| | - Lachlan S Brown
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Level 4, Medical Sciences Precinct, 17 Liverpool St, Hobart, TAS, 7000, Australia
| | - Alastair J Fortune
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia
| | - Nicholas B Blackburn
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia
| | - Jessica L Fletcher
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia
| | - Jake M Cashion
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Level 4, Medical Sciences Precinct, 17 Liverpool St, Hobart, TAS, 7000, Australia
| | - Jana Talbot
- Wicking Dementia Education and Research Centre, College of Health and Medicine, University of Tasmania, Hobart, Australia
| | - Alice Pébay
- Department of Anatomy and Physiology, The University of Melbourne, Melbourne, Australia
- Department of Surgery, Royal Melbourne Hospital, The University of Melbourne, Melbourne, Australia
| | - Alex W Hewitt
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Level 4, Medical Sciences Precinct, 17 Liverpool St, Hobart, TAS, 7000, Australia
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia
- Department of Anatomy and Physiology, The University of Melbourne, Melbourne, Australia
- Department of Surgery, Royal Melbourne Hospital, The University of Melbourne, Melbourne, Australia
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia
| | - Gary P Morris
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Level 4, Medical Sciences Precinct, 17 Liverpool St, Hobart, TAS, 7000, Australia
| | - Kaylene M Young
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia
| | - Anthony L Cook
- Wicking Dementia Education and Research Centre, College of Health and Medicine, University of Tasmania, Hobart, Australia
| | - Brad A Sutherland
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Level 4, Medical Sciences Precinct, 17 Liverpool St, Hobart, TAS, 7000, Australia.
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Brown LS, King NE, Courtney JM, Gasperini RJ, Foa L, Howells DW, Sutherland BA. Brain pericytes in culture display diverse morphological and functional phenotypes. Cell Biol Toxicol 2023; 39:2999-3014. [PMID: 37322257 PMCID: PMC10693527 DOI: 10.1007/s10565-023-09814-9] [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: 11/18/2022] [Accepted: 05/23/2023] [Indexed: 06/17/2023]
Abstract
Pericytes play several important functions in the neurovascular unit including contractile control of capillaries, maintenance of the BBB, regulation of angiogenesis, and neuroinflammation. There exists a continuum of pericyte subtypes along the vascular tree which exhibit both morphological and transcriptomic differences. While different functions have been associated with the pericyte subtypes in vivo, numerous recent publications have used a primary human brain vascular pericytes (HBVP) cell line where this pericyte heterogeneity has not been considered. Here, we used primary HBVP cultures, high-definition imaging, cell motility tracking, and immunocytochemistry to characterise morphology, protein expression, and contractile behaviour to determine whether heterogeneity of pericytes also exists in cultures. We identified five distinct morphological subtypes that were defined using both qualitative criteria and quantitative shape analysis. The proportion of each subtype present within the culture changed as passage number increased, but pericytes did not change morphological subtype over short time periods. The rate and extent of cellular and membrane motility differed across the subtypes. Immunocytochemistry revealed differential expression of alpha-smooth muscle actin (αSMA) across subtypes. αSMA is essential for cell contractility, and consequently, only subtypes with high αSMA expression contracted in response to physiological vasoconstrictors endothelin-1 (ET1) and noradrenaline (NA). We conclude that there are distinct morphological subtypes in HBVP culture, which display different behaviours. This has significance for the use of HBVP when modelling pericyte physiology in vitro where relevance to in vivo pericyte subtypes along the vascular tree must be considered.
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Affiliation(s)
- Lachlan S Brown
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Level 4 Medical Sciences Precinct, 17 Liverpool St, Hobart, TAS, 7000, Australia
| | - Natalie E King
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Level 4 Medical Sciences Precinct, 17 Liverpool St, Hobart, TAS, 7000, Australia
| | - Jo-Maree Courtney
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Level 4 Medical Sciences Precinct, 17 Liverpool St, Hobart, TAS, 7000, Australia
| | - Robert J Gasperini
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Level 4 Medical Sciences Precinct, 17 Liverpool St, Hobart, TAS, 7000, Australia
| | - Lisa Foa
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Level 4 Medical Sciences Precinct, 17 Liverpool St, Hobart, TAS, 7000, Australia
- School of Psychological Sciences, College of Health and Medicine, University of Tasmania, Hobart, TAS, Australia
| | - David W Howells
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Level 4 Medical Sciences Precinct, 17 Liverpool St, Hobart, TAS, 7000, Australia
| | - Brad A Sutherland
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Level 4 Medical Sciences Precinct, 17 Liverpool St, Hobart, TAS, 7000, Australia.
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3
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Whitehead B, Karelina K, Weil ZM. Pericyte dysfunction is a key mediator of the risk of cerebral ischemia. J Neurosci Res 2023; 101:1840-1848. [PMID: 37724604 DOI: 10.1002/jnr.25245] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 08/15/2023] [Accepted: 09/04/2023] [Indexed: 09/21/2023]
Abstract
Pericytes are critical yet understudied cells that are a central component of the neurovascular unit. They are connected to the cerebrovascular endothelium and help control vascular contractility and maintain the blood-brain barrier. Pericyte dysfunction has the potential to mediate many of the deleterious vascular consequences of ischemic stroke. Current therapeutics are designed to be administered after stroke onset and limit damage, but there are few options to target vascular risk factors pre-ischemia which likely contribute to stroke outcomes. Here, we focus on the role of pericytes in health and disease, and discuss how pericyte dysfunction can increase the risk of ischemic injury. Additionally, we note that despite the importance of pericytes in cerebrovascular disease, there are relatively few current therapeutic options that target pericyte function.
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Affiliation(s)
- Bailey Whitehead
- Department of Neuroscience and Rockefeller Neuroscience Institute, West Virginia University, Morgantown, West Virginia, USA
| | - Kate Karelina
- Department of Neuroscience and Rockefeller Neuroscience Institute, West Virginia University, Morgantown, West Virginia, USA
| | - Zachary M Weil
- Department of Neuroscience and Rockefeller Neuroscience Institute, West Virginia University, Morgantown, West Virginia, USA
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Fu J, Liang H, Yuan P, Wei Z, Zhong P. Brain pericyte biology: from physiopathological mechanisms to potential therapeutic applications in ischemic stroke. Front Cell Neurosci 2023; 17:1267785. [PMID: 37780206 PMCID: PMC10536258 DOI: 10.3389/fncel.2023.1267785] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 08/30/2023] [Indexed: 10/03/2023] Open
Abstract
Pericytes play an indispensable role in various organs and biological processes, such as promoting angiogenesis, regulating microvascular blood flow, and participating in immune responses. Therefore, in this review, we will first introduce the discovery and development of pericytes, identification methods and functional characteristics, then focus on brain pericytes, on the one hand, to summarize the functions of brain pericytes under physiological conditions, mainly discussing from the aspects of stem cell characteristics, contractile characteristics and paracrine characteristics; on the other hand, to summarize the role of brain pericytes under pathological conditions, mainly taking ischemic stroke as an example. Finally, we will discuss and analyze the application and development of pericytes as therapeutic targets, providing the research basis and direction for future microvascular diseases, especially ischemic stroke treatment.
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Affiliation(s)
- Jiaqi Fu
- School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai, China
- Department of Neurology, Shidong Hospital, Yangpu District, Shanghai, China
| | - Huazheng Liang
- Monash Suzhou Research Institute, Suzhou, Jiangsu, China
| | - Ping Yuan
- Department of Cardio-Pulmonary Circulation, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Zhenyu Wei
- Department of Neurology, Shidong Hospital, Yangpu District, Shanghai, China
| | - Ping Zhong
- School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai, China
- Department of Neurology, Shidong Hospital, Yangpu District, Shanghai, China
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5
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Morris GP, Foster CG, Courtney J, Collins JM, Cashion JM, Brown LS, Howells DW, DeLuca GC, Canty AJ, King AE, Ziebell JM, Sutherland BA. Microglia directly associate with pericytes in the central nervous system. Glia 2023; 71:1847-1869. [PMID: 36994950 PMCID: PMC10952742 DOI: 10.1002/glia.24371] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 03/15/2023] [Accepted: 03/20/2023] [Indexed: 03/31/2023]
Abstract
Cerebral blood flow (CBF) is important for the maintenance of brain function and its dysregulation has been implicated in Alzheimer's disease (AD). Microglia associations with capillaries suggest they may play a role in the regulation of CBF or the blood-brain-barrier (BBB). We explored the relationship between microglia and pericytes, a vessel-resident cell type that has a major role in the control of CBF and maintenance of the BBB, discovering a spatially distinct subset of microglia that closely associate with pericytes. We termed these pericyte-associated microglia (PEM). PEM are present throughout the brain and spinal cord in NG2DsRed × CX3 CR1+/GFP mice, and in the human frontal cortex. Using in vivo two-photon microscopy, we found microglia residing adjacent to pericytes at all levels of the capillary tree and found they can maintain their position for at least 28 days. PEM can associate with pericytes lacking astroglial endfeet coverage and capillary vessel width is increased beneath pericytes with or without an associated PEM, but capillary width decreases if a pericyte loses a PEM. Deletion of the microglia fractalkine receptor (CX3 CR1) did not disrupt the association between pericytes and PEM. Finally, we found the proportion of microglia that are PEM declines in the superior frontal gyrus in AD. In summary, we identify microglia that specifically associate with pericytes and find these are reduced in number in AD, which may be a novel mechanism contributing to vascular dysfunction in neurodegenerative diseases.
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Affiliation(s)
- Gary P. Morris
- Tasmanian School of Medicine, College of Health and MedicineUniversity of TasmaniaHobartTasmaniaAustralia
| | - Catherine G. Foster
- Tasmanian School of Medicine, College of Health and MedicineUniversity of TasmaniaHobartTasmaniaAustralia
| | - Jo‐Maree Courtney
- Tasmanian School of Medicine, College of Health and MedicineUniversity of TasmaniaHobartTasmaniaAustralia
| | - Jessica M. Collins
- Wicking Dementia Research and Education Centre, College of Health and MedicineUniversity of TasmaniaHobartTasmaniaAustralia
| | - Jake M. Cashion
- Tasmanian School of Medicine, College of Health and MedicineUniversity of TasmaniaHobartTasmaniaAustralia
| | - Lachlan S. Brown
- Tasmanian School of Medicine, College of Health and MedicineUniversity of TasmaniaHobartTasmaniaAustralia
| | - David W. Howells
- Tasmanian School of Medicine, College of Health and MedicineUniversity of TasmaniaHobartTasmaniaAustralia
| | - Gabriele C. DeLuca
- Nuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUK
| | - Alison J. Canty
- Wicking Dementia Research and Education Centre, College of Health and MedicineUniversity of TasmaniaHobartTasmaniaAustralia
- Global Brain Health InstituteTrinity CollegeDublinIreland
| | - Anna E. King
- Wicking Dementia Research and Education Centre, College of Health and MedicineUniversity of TasmaniaHobartTasmaniaAustralia
| | - Jenna M. Ziebell
- Wicking Dementia Research and Education Centre, College of Health and MedicineUniversity of TasmaniaHobartTasmaniaAustralia
| | - Brad A. Sutherland
- Tasmanian School of Medicine, College of Health and MedicineUniversity of TasmaniaHobartTasmaniaAustralia
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6
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Yao D, Zhang R, Xie M, Ding F, Wang M, Wang W. Updated Understanding of the Glial-Vascular Unit in Central Nervous System Disorders. Neurosci Bull 2023; 39:503-518. [PMID: 36374471 PMCID: PMC10043098 DOI: 10.1007/s12264-022-00977-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 09/04/2022] [Indexed: 11/16/2022] Open
Abstract
The concept of the glial-vascular unit (GVU) was raised recently to emphasize the close associations between brain cells and cerebral vessels, and their coordinated reactions to diverse neurological insults from a "glio-centric" view. GVU is a multicellular structure composed of glial cells, perivascular cells, and perivascular space. Each component is closely linked, collectively forming the GVU. The central roles of glial and perivascular cells and their multi-level interconnections in the GVU under normal conditions and in central nervous system (CNS) disorders have not been elucidated in detail. Here, we comprehensively review the intensive interactions between glial cells and perivascular cells in the niche of perivascular space, which take part in the modulation of cerebral blood flow and angiogenesis, formation of the blood-brain barrier, and clearance of neurotoxic wastes. Next, we discuss dysfunctions of the GVU in various neurological diseases, including ischemic stroke, spinal cord injury, Alzheimer's disease, and major depression disorder. In addition, we highlight the possible therapies targeting the GVU, which may have potential clinical applications.
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Affiliation(s)
- Di Yao
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Ruoying Zhang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Minjie Xie
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Fengfei Ding
- Department of Pharmacology, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
| | - Minghuan Wang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Wei Wang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
- Key Laboratory of Neurological Diseases of the Chinese Ministry of Education, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
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7
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Zhu WM, Neuhaus A, Beard DJ, Sutherland BA, DeLuca GC. Neurovascular coupling mechanisms in health and neurovascular uncoupling in Alzheimer's disease. Brain 2022; 145:2276-2292. [PMID: 35551356 PMCID: PMC9337814 DOI: 10.1093/brain/awac174] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 05/05/2022] [Accepted: 05/07/2022] [Indexed: 11/25/2022] Open
Abstract
To match the metabolic demands of the brain, mechanisms have evolved to couple neuronal activity to vasodilation, thus increasing local cerebral blood flow and delivery of oxygen and glucose to active neurons. Rather than relying on metabolic feedback signals such as the consumption of oxygen or glucose, the main signalling pathways rely on the release of vasoactive molecules by neurons and astrocytes, which act on contractile cells. Vascular smooth muscle cells and pericytes are the contractile cells associated with arterioles and capillaries, respectively, which relax and induce vasodilation. Much progress has been made in understanding the complex signalling pathways of neurovascular coupling, but issues such as the contributions of capillary pericytes and astrocyte calcium signal remain contentious. Study of neurovascular coupling mechanisms is especially important as cerebral blood flow dysregulation is a prominent feature of Alzheimer’s disease. In this article we will discuss developments and controversies in the understanding of neurovascular coupling and finish by discussing current knowledge concerning neurovascular uncoupling in Alzheimer’s disease.
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Affiliation(s)
- Winston M Zhu
- Oxford Medical School, University of Oxford, Oxford, UK
| | - Ain Neuhaus
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Daniel J Beard
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, UK.,School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia
| | - Brad A Sutherland
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Hobart, Australia
| | - Gabriele C DeLuca
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
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8
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Pharmacological PDGFRβ inhibitors imatinib and sunitinib cause human brain pericyte death in vitro. Toxicol Appl Pharmacol 2022; 444:116025. [DOI: 10.1016/j.taap.2022.116025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 04/11/2022] [Accepted: 04/11/2022] [Indexed: 11/17/2022]
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Hibbs E, Love S, Miners JS. Pericyte Contractile Responses to Endothelin-1 and Aβ Peptides: Assessment by Electrical Impedance Assay. Front Cell Neurosci 2021; 15:723953. [PMID: 34489644 PMCID: PMC8417582 DOI: 10.3389/fncel.2021.723953] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 07/28/2021] [Indexed: 11/13/2022] Open
Abstract
Pericytes are vascular mural cells that contract and relax in response to vasoactive stimuli to regulate neurovascular coupling and cerebral blood flow. Pericytes are damaged and degenerate in Alzheimer's disease (AD). We previously showed that the level of the regulatory vasoconstrictor, endothelin-1 (EDN1), is elevated in AD cerebral cortex and upregulated by amyloid-beta (Aβ). We have used electrical impedance analysis to monitor the contractile and proliferative response of cultured human fetal and adult brain-derived pericytes to EDN1 in real-time. EDN1 caused transient, dose-dependent contraction of fetal and adult brain pericytes that was mediated by EDN1 type A receptors and increased the subsequent proliferation of fetal but not adult cells. The contractile responses to EDN1 were weaker in the adult pericytes. The EDN1-mediated contractile response of fetal pericytes was unchanged after exposure to Aβ1 - 40 or Aβ1 - 42 (0.1-10 μM) for 1 h but both contraction and subsequent relaxation were significantly impaired upon exposure to Aβ for 24 h. These data suggest that chronic exposure to Aβ interferes with EDN1-mediated pericyte contractility, potentially contributing to neurovascular uncoupling and reduced cerebral blood flow in AD.
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Affiliation(s)
- Elliott Hibbs
- Dementia Research Group, Clinical Neurosciences, University of Bristol, Bristol, United Kingdom
| | - Seth Love
- Dementia Research Group, Clinical Neurosciences, University of Bristol, Bristol, United Kingdom
| | - J Scott Miners
- Dementia Research Group, Clinical Neurosciences, University of Bristol, Bristol, United Kingdom
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Cao L, Zhou Y, Chen M, Li L, Zhang W. Pericytes for Therapeutic Approaches to Ischemic Stroke. Front Neurosci 2021; 15:629297. [PMID: 34239409 PMCID: PMC8259582 DOI: 10.3389/fnins.2021.629297] [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: 11/14/2020] [Accepted: 05/11/2021] [Indexed: 12/18/2022] Open
Abstract
Pericytes are perivascular multipotent cells located on capillaries. Although pericytes are discovered in the nineteenth century, recent studies have found that pericytes play an important role in maintaining the blood—brain barrier (BBB) and regulating the neurovascular system. In the neurovascular unit, pericytes perform their functions by coordinating the crosstalk between endothelial, glial, and neuronal cells. Dysfunction of pericytes can lead to a variety of diseases, including stroke and other neurological disorders. Recent studies have suggested that pericytes can serve as a therapeutic target in ischemic stroke. In this review, we first summarize the biology and functions of pericytes in the central nervous system. Then, we focus on the role of dysfunctional pericytes in the pathogenesis of ischemic stroke. Finally, we discuss new therapies for ischemic stroke based on targeting pericytes.
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Affiliation(s)
- Lu Cao
- Department of Anesthesiology, Pain and Perioperative Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Yanbo Zhou
- Department of Anesthesiology, Pain and Perioperative Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Mengguang Chen
- Department of Anesthesiology, Pain and Perioperative Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Li Li
- Department of Anesthesiology, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Wei Zhang
- Department of Anesthesiology, Pain and Perioperative Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
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11
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Brain capillary pericytes exert a substantial but slow influence on blood flow. Nat Neurosci 2021; 24:633-645. [PMID: 33603231 PMCID: PMC8102366 DOI: 10.1038/s41593-020-00793-2] [Citation(s) in RCA: 168] [Impact Index Per Article: 56.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 12/23/2020] [Indexed: 01/30/2023]
Abstract
The majority of the brain's vasculature is composed of intricate capillary networks lined by capillary pericytes. However, it remains unclear whether capillary pericytes influence blood flow. Using two-photon microscopy to observe and manipulate brain capillary pericytes in vivo, we find that their optogenetic stimulation decreases lumen diameter and blood flow, but with slower kinetics than similar stimulation of mural cells on upstream pial and precapillary arterioles. This slow vasoconstriction was inhibited by the clinically used vasodilator fasudil, a Rho-kinase inhibitor that blocks contractile machinery. Capillary pericytes were also slower to constrict back to baseline following hypercapnia-induced dilation, and slower to dilate towards baseline following optogenetically induced vasoconstriction. Optical ablation of single capillary pericytes led to sustained local dilation and a doubling of blood cell flux selectively in capillaries lacking pericyte contact. These data indicate that capillary pericytes contribute to basal blood flow resistance and slow modulation of blood flow throughout the brain.
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12
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Lee LL, Khakoo AY, Chintalgattu V. Cardiac pericytes function as key vasoactive cells to regulate homeostasis and disease. FEBS Open Bio 2020; 11:207-225. [PMID: 33135334 PMCID: PMC7780101 DOI: 10.1002/2211-5463.13021] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 08/24/2020] [Accepted: 10/30/2020] [Indexed: 01/13/2023] Open
Abstract
Pericytes (PCs)—mural cells that envelop endothelial cells (ECs) of microvessels—regulate tissue‐specific vasculature development as well as maturation and maintenance of endothelial barrier integrity. However, little is known about their tissue‐specific function in the heart. Specifically, the mechanism by which cardiac PCs constrict coronary capillaries remains undetermined. To gain insights into the function of cardiac PCs at the cellular level, we isolated NG2+ PDGFRβ+ CD146+ CD34− CD31− CD45− PCs for detailed characterization. Functionally, we provide evidence that these PCs increased transepithelial electrical resistance and decreased endothelial permeability. We show for the first time that this population of PCs express contractile proteins, are stimulated by adrenergic signaling, and demonstrate stereotypical contraction and relaxation. Furthermore, we also studied for the first time, the PCs in in vitro models of disease. PCs in hypoxia activated the hypoxia‐inducible factor 1 alpha pathway, increased secretion of angiogenic factors, and caused cellular apoptosis. Supraphysiological levels of low‐density lipoprotein decreased PC proliferation and induced lipid droplet accumulation. Elevated glucose levels triggered a proinflammatory response. Taken together, our study characterizes cardiac PCs under in vitro disease conditions and supports the hypothesis that cardiac PCs are key vasoactive cells that can regulate blood flow in the heart.
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Affiliation(s)
- Linda L Lee
- Department of Cardiometabolic Disorders, Amgen Research and Discovery, Amgen Inc., South San Francisco, CA, USA
| | - Aarif Y Khakoo
- Department of Drug Development, Calico Labs, South San Francisco, CA, USA
| | - Vishnu Chintalgattu
- Department of Cardiometabolic Disorders, Amgen Research and Discovery, Amgen Inc., South San Francisco, CA, USA
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13
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Hørlyck S, Cai C, Helms HCC, Lauritzen M, Brodin B. ATP induces contraction of cultured brain capillary pericytes via activation of P2Y-type purinergic receptors. Am J Physiol Heart Circ Physiol 2020; 320:H699-H712. [PMID: 33306443 DOI: 10.1152/ajpheart.00560.2020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Brain capillary pericytes have been suggested to play a role in the regulation of cerebral blood flow under physiological and pathophysiological conditions. ATP has been shown to cause constriction of capillaries under ischemic conditions and suggested to be involved in the "no-reflow" phenomenon. To investigate the effects of extracellular ATP on pericyte cell contraction, we studied purinergic receptor activation of cultured bovine brain capillary pericytes. We measured intracellular Ca2+ concentration ([Ca2+]i) responses to purinergic agonists with the fluorescent indicators fura-2 and Cal-520 and estimated contraction of pericytes as relative change in cell area, using real-time confocal imaging. Addition of ATP caused an increase in cytosolic calcium and contraction of the brain capillary pericytes, both reversible and inhibited by the purinergic receptor antagonist pyridoxalphosphate-6-azophenyl-2',4'-disulfonic acid (PPADS). Furthermore, we demonstrated that ATP-induced contraction could be eliminated by intracellular calcium chelation with BAPTA, indicating that the contraction was mediated via purinergic P2-type receptor-mediated [Ca2+]i signaling. ATP stimulation induced inositol triphosphate signaling, consistent with the notion of P2Y receptor activation. Receptor profiling studies demonstrated the presence of P2Y1 and P2Y2 receptors, using ATP, UTP, ADP, and the subtype specific agonists MRS2365 (P2Y1) and 2-thio-UTP (P2Y2). Addition of specific P2X agonists only caused an [Ca2+]i increase at high concentrations, attributed to activation of inositol triphosphate signaling. Our results suggest that contraction of brain capillary pericytes in vitro by activation of P2Y-type purinergic receptors is caused by intracellular calcium release. This adds more mechanistic understanding of the role of pericytes in vessel constriction and points toward P2Y receptors as potential therapeutic targets.NEW & NOTEWORTHY The study concerns brain capillary pericytes, which have been suggested to play a role in the regulation of cerebral blood flow. We show that extracellular ATP causes contraction of primary brain pericytes by stimulation of purinergic receptors and subsequent release of intracellular Ca2+ concentration ([Ca2+]i). The contraction is mainly mediated through activation of P2Y-receptor subtypes, including P2Y1 and P2Y2. These findings add more mechanistic understanding of the role of pericytes in regulation of capillary blood flow. ATP was earlier suggested to be involved in capillary constriction in brain pathologies, and our study gives a detailed account of a part of this important mechanism.
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Affiliation(s)
- Sofie Hørlyck
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Changsi Cai
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Martin Lauritzen
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Department of Clinical Neurophysiology, Rigshospitalet, Copenhagen, Denmark
| | - Birger Brodin
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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14
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Beard DJ, Brown LS, Sutherland BA. The rise of pericytes in neurovascular research. J Cereb Blood Flow Metab 2020; 40:2366-2373. [PMID: 32955956 PMCID: PMC7820692 DOI: 10.1177/0271678x20958497] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 08/06/2020] [Accepted: 08/16/2020] [Indexed: 01/05/2023]
Abstract
The popularity of pericyte research is increasing, and this was not more evident than at the recent 2019 Brain meeting in Yokohama which featured a large number of presentations focused on brain pericyte research, including the Presidential Symposium. In this article, we will provide a history of brain pericyte research, present the results of our analysis showing a substantial increase in brain pericyte research presented at Brain meetings since 2005, suggest reasons for their increased popularity, and comment on what the future holds for brain pericyte research.
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Affiliation(s)
- Daniel J Beard
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Lachlan S Brown
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Hobart, Australia
| | - Brad A Sutherland
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Hobart, Australia
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15
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Medina-Flores F, Hurtado-Alvarado G, Contis-Montes de Oca A, López-Cervantes SP, Konigsberg M, Deli MA, Gómez-González B. Sleep loss disrupts pericyte-brain endothelial cell interactions impairing blood-brain barrier function. Brain Behav Immun 2020; 89:118-132. [PMID: 32485292 DOI: 10.1016/j.bbi.2020.05.077] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 04/12/2020] [Accepted: 05/29/2020] [Indexed: 10/24/2022] Open
Abstract
Sleep loss in the rat increases blood-brain barrier permeability to circulating molecules by disrupting interendothelial tight junctions. Despite the description of the ultrastructure of cerebral microvessels and the evidence of an apparent pericyte detachment from capillary wall in sleep restricted rats the effect of sleep loss on pericytes is unknown. Here we characterized the interactions between pericytes and brain endothelial cells after sleep loss using male Wistar rats. Animals were sleep-restricted 20 h daily with 4 h sleep recovery for 10 days. At the end of the sleep restriction, brain microvessels (MVs) were isolated from cerebral cortex and hippocampus and processed for Western blot and immunocytochemistry to evaluate markers of pericyte-endothelial cell interaction (connexin 43, PDGFR-β), tight junction proteins, and proinflammatory mediator proteins (MMP9, A2A adenosine receptor, CD73, NFκB). Sleep restriction reduced PDGFR-β and connexin 43 expression in MVs; in addition, scanning electron microscopy micrographs showed that pericytes were detached from capillary walls, but did not undergo apoptosis (as depicted by a reduced active caspase-3 expression). Sleep restriction also decreased tight junction protein expression in MVs and increased BBB permeability to low- and high-molecular weight tracers in in vivo permeability assays. Those alterations seemed to depend on a low-grade inflammatory status as reflected by the increased expression of phosphorylated NFκB and A2A adenosine receptor in brain endothelial cells from the sleep-restricted rats. Our data show that pericyte-brain endothelial cell interaction is altered by sleep restriction; this evidence is essential to understand the role of sleep in regulating blood-brain barrier function.
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Affiliation(s)
- Fernanda Medina-Flores
- Area of Neurosciences, Dept. Biology of Reproduction, CBS, Universidad Autónoma Metropolitana, Unidad Iztapalapa, Mexico City, Mexico; Posgrado en Biología Experimental, Universidad Autónoma Metropolitana, Unidad Iztapalapa, Mexico City, Mexico
| | - Gabriela Hurtado-Alvarado
- Area of Neurosciences, Dept. Biology of Reproduction, CBS, Universidad Autónoma Metropolitana, Unidad Iztapalapa, Mexico City, Mexico
| | - Arturo Contis-Montes de Oca
- Universidad Nacional Autónoma de México (UNAM), Facultad de Estudios Superiores (FES) Iztacala, Optometría, Mexico
| | - Stefanie Paola López-Cervantes
- Posgrado en Biología Experimental, Universidad Autónoma Metropolitana, Unidad Iztapalapa, Mexico City, Mexico; Laboratorio de Bioenergética y Envejecimiento Celular, Dept. Health Sciences, Universidad Autónoma Metropolitana, Unidad Iztapalapa, Mexico D.F., Mexico
| | - Mina Konigsberg
- Laboratorio de Bioenergética y Envejecimiento Celular, Dept. Health Sciences, Universidad Autónoma Metropolitana, Unidad Iztapalapa, Mexico D.F., Mexico.
| | - Maria A Deli
- Institute of Biophysics, Biological Research Centre, Szeged, Hungary; Department of Cell Biology and Molecular Medicine, University of Szeged, Szeged, Hungary.
| | - Beatriz Gómez-González
- Area of Neurosciences, Dept. Biology of Reproduction, CBS, Universidad Autónoma Metropolitana, Unidad Iztapalapa, Mexico City, Mexico.
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16
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Špiranec Spes K, Chen W, Krebes L, Völker K, Abeßer M, Eder Negrin P, Cellini A, Nickel A, Nikolaev VO, Hofmann F, Schuh K, Schweda F, Kuhn M. Heart-Microcirculation Connection: Effects of ANP (Atrial Natriuretic Peptide) on Pericytes Participate in the Acute and Chronic Regulation of Arterial Blood Pressure. Hypertension 2020; 76:1637-1648. [PMID: 32951468 DOI: 10.1161/hypertensionaha.120.15772] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Cardiac ANP (atrial natriuretic peptide) moderates arterial blood pressure. The mechanisms mediating its hypotensive effects are complex and involve inhibition of the renin-angiotensin-aldosterone system, increased natriuresis, endothelial permeability, and vasodilatation. The contribution of the direct vasodilating effects of ANP to blood pressure homeostasis is controversial because variable levels of the ANP receptor, GC-A (guanylyl cyclase-A), are expressed among vascular beds. Here, we show that ANP stimulates GC-A/cyclic GMP signaling in cultured microvascular pericytes and thereby the phosphorylation of the regulatory subunit of myosin phosphatase 1 by cGMP-dependent protein kinase I. Moreover, ANP prevents the calcium and contractile responses of pericytes to endothelin-1 as well as microvascular constrictions. In mice with conditional inactivation (knock-out) of GC-A in microcirculatory pericytes, such vasodilating effects of ANP on precapillary arterioles and capillaries were fully abolished. Concordantly, these mice have increased blood pressure despite preserved renal excretory function. Furthermore, acute intravascular volume expansion, which caused release of cardiac ANP, did not affect blood pressure of control mice but provoked hypertensive reactions in pericyte GC-A knock-out littermates. We conclude that GC-A/cGMP-dependent modulation of pericytes and microcirculatory tone contributes to the acute and chronic moderation of arterial blood pressure by ANP. Graphic Abstract A graphic abstract is available for this article.
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Affiliation(s)
- Katarina Špiranec Spes
- From the Institute of Physiology, University of Würzburg (K.S.S., W.C., L.K., K.V., M.A., K.S., M.K.), University Hospital Würzburg, Germany.,Comprehensive Heart Failure Center (K.S.S., W.C., P.E.N., A.C., A.N., M.K.), University Hospital Würzburg, Germany
| | - Wen Chen
- From the Institute of Physiology, University of Würzburg (K.S.S., W.C., L.K., K.V., M.A., K.S., M.K.), University Hospital Würzburg, Germany.,Comprehensive Heart Failure Center (K.S.S., W.C., P.E.N., A.C., A.N., M.K.), University Hospital Würzburg, Germany.,The Affiliated Haimen Hospital, Nantong University, Jiangsu, China (W.C.)
| | - Lisa Krebes
- From the Institute of Physiology, University of Würzburg (K.S.S., W.C., L.K., K.V., M.A., K.S., M.K.), University Hospital Würzburg, Germany
| | - Katharina Völker
- From the Institute of Physiology, University of Würzburg (K.S.S., W.C., L.K., K.V., M.A., K.S., M.K.), University Hospital Würzburg, Germany
| | - Marco Abeßer
- From the Institute of Physiology, University of Würzburg (K.S.S., W.C., L.K., K.V., M.A., K.S., M.K.), University Hospital Würzburg, Germany
| | - Petra Eder Negrin
- Comprehensive Heart Failure Center (K.S.S., W.C., P.E.N., A.C., A.N., M.K.), University Hospital Würzburg, Germany
| | - Antonella Cellini
- Comprehensive Heart Failure Center (K.S.S., W.C., P.E.N., A.C., A.N., M.K.), University Hospital Würzburg, Germany
| | - Alexander Nickel
- Comprehensive Heart Failure Center (K.S.S., W.C., P.E.N., A.C., A.N., M.K.), University Hospital Würzburg, Germany
| | - Viacheslav O Nikolaev
- Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.)
| | - Franz Hofmann
- Institute of Pharmacology and Toxicology, TU Munich, Germany (F.H.)
| | - Kai Schuh
- From the Institute of Physiology, University of Würzburg (K.S.S., W.C., L.K., K.V., M.A., K.S., M.K.), University Hospital Würzburg, Germany
| | - Frank Schweda
- Institute of Physiology, University of Regensburg, Germany (F.S.)
| | - Michaela Kuhn
- From the Institute of Physiology, University of Würzburg (K.S.S., W.C., L.K., K.V., M.A., K.S., M.K.), University Hospital Würzburg, Germany
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17
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Mészáros Á, Molnár K, Nógrádi B, Hernádi Z, Nyúl-Tóth Á, Wilhelm I, Krizbai IA. Neurovascular Inflammaging in Health and Disease. Cells 2020; 9:cells9071614. [PMID: 32635451 PMCID: PMC7407516 DOI: 10.3390/cells9071614] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 07/02/2020] [Indexed: 12/19/2022] Open
Abstract
Aging is characterized by a chronic low-grade sterile inflammation dubbed as inflammaging, which in part originates from accumulating cellular debris. These, acting as danger signals with many intrinsic factors such as cytokines, are sensed by a network of pattern recognition receptors and other cognate receptors, leading to the activation of inflammasomes. Due to the inflammasome activity-dependent increase in the levels of pro-inflammatory interleukins (IL-1β, IL-18), inflammation is initiated, resulting in tissue injury in various organs, the brain and the spinal cord included. Similarly, in age-related diseases of the central nervous system (CNS), inflammasome activation is a prominent moment, in which cells of the neurovascular unit occupy a significant position. In this review, we discuss the inflammatory changes in normal aging and summarize the current knowledge on the role of inflammasomes and contributing mechanisms in common CNS diseases, namely Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis and stroke, all of which occur more frequently with aging.
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Affiliation(s)
- Ádám Mészáros
- Institute of Biophysics, Biological Research Centre, 6726 Szeged, Hungary; (Á.M.); (K.M.); (B.N.); (Z.H.); (Á.N.-T.); (I.W.)
- Doctoral School of Biology, University of Szeged, 6726 Szeged, Hungary
| | - Kinga Molnár
- Institute of Biophysics, Biological Research Centre, 6726 Szeged, Hungary; (Á.M.); (K.M.); (B.N.); (Z.H.); (Á.N.-T.); (I.W.)
- Theoretical Medicine Doctoral School, University of Szeged, 6720 Szeged, Hungary
| | - Bernát Nógrádi
- Institute of Biophysics, Biological Research Centre, 6726 Szeged, Hungary; (Á.M.); (K.M.); (B.N.); (Z.H.); (Á.N.-T.); (I.W.)
- Foundation for the Future of Biomedical Sciences in Szeged, Szeged Scientists Academy, 6720 Szeged, Hungary
| | - Zsófia Hernádi
- Institute of Biophysics, Biological Research Centre, 6726 Szeged, Hungary; (Á.M.); (K.M.); (B.N.); (Z.H.); (Á.N.-T.); (I.W.)
- Foundation for the Future of Biomedical Sciences in Szeged, Szeged Scientists Academy, 6720 Szeged, Hungary
| | - Ádám Nyúl-Tóth
- Institute of Biophysics, Biological Research Centre, 6726 Szeged, Hungary; (Á.M.); (K.M.); (B.N.); (Z.H.); (Á.N.-T.); (I.W.)
- Vascular Cognitive Impairment and Neurodegeneration Program, Reynolds Oklahoma Center on Aging/Oklahoma Center for Geroscience, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Imola Wilhelm
- Institute of Biophysics, Biological Research Centre, 6726 Szeged, Hungary; (Á.M.); (K.M.); (B.N.); (Z.H.); (Á.N.-T.); (I.W.)
- Institute of Life Sciences, Vasile Goldiş Western University of Arad, 310414 Arad, Romania
| | - István A. Krizbai
- Institute of Biophysics, Biological Research Centre, 6726 Szeged, Hungary; (Á.M.); (K.M.); (B.N.); (Z.H.); (Á.N.-T.); (I.W.)
- Institute of Life Sciences, Vasile Goldiş Western University of Arad, 310414 Arad, Romania
- Correspondence: ; Tel.: +36-62-599-794
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18
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Abstract
Purpose of review Pericytes are essential components of capillaries in many tissues and organs, contributing to vessel stability and integrity, with additional contributions to microvascular function still being discovered. We review current and foundational studies identifying pericyte differentiation mechanics and their roles in the earliest stages of vessel formation. Recent findings Recent advances in pericyte-focused tools and models have illuminated critical aspects of pericyte biology including their roles in vascular development.Pericytes likely collaborate with endothelial cells undergoing vasculogenesis, initiating direct interactions during sprouting and intussusceptive angiogenesis. Pericytes also provide important regulation of vascular growth including mechanisms underlying vessel pruning, rarefaction, and subsequent regrowth.
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Affiliation(s)
- Laura Beth Payne
- Center for Heart and Reparative Medicine Research, Fralin Biomedical Research Institute at Virginia Tech-Carilion, Roanoke, VA 24016, USA
| | - Maruf Hoque
- Center for Heart and Reparative Medicine Research, Fralin Biomedical Research Institute at Virginia Tech-Carilion, Roanoke, VA 24016, USA.,Graduate Program in Translational Biology, Medicine and Health, Virginia Tech, Blacksburg, VA 24061, USA
| | - Clifton Houk
- Virginia Tech Carilion School of Medicine, Roanoke, VA, 24016, USA.,Previous Affiliations
| | - Jordan Darden
- Center for Heart and Reparative Medicine Research, Fralin Biomedical Research Institute at Virginia Tech-Carilion, Roanoke, VA 24016, USA.,Graduate Program in Translational Biology, Medicine and Health, Virginia Tech, Blacksburg, VA 24061, USA.,Previous Affiliations
| | - John C Chappell
- Center for Heart and Reparative Medicine Research, Fralin Biomedical Research Institute at Virginia Tech-Carilion, Roanoke, VA 24016, USA.,Virginia Tech Carilion School of Medicine, Roanoke, VA, 24016, USA.,Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA 24061, USA
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19
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Pardridge WM. The Isolated Brain Microvessel: A Versatile Experimental Model of the Blood-Brain Barrier. Front Physiol 2020; 11:398. [PMID: 32457645 PMCID: PMC7221163 DOI: 10.3389/fphys.2020.00398] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Accepted: 04/02/2020] [Indexed: 12/12/2022] Open
Abstract
A versatile experimental model for the investigation of the blood-brain barrier (BBB), including the neuro-vascular unit, is the isolated brain microvessel preparation. Brain microvessels are primarily comprised of endothelial cells, but also include pericytes, pre-capillary arteriolar smooth muscle cells, astrocyte foot processes, and occasional nerve endings. These microvessels can be isolated from brain with a 3 h procedure, and the microvessels are free of brain parenchyma. Brain microvessels have been isolated from fresh animal brain, fresh human brain obtained at neurosurgery, as well as fresh or frozen autopsy human brain. Brain microvessels are the starting point for isolation of brain microvessel RNA, which then enables the production of BBB cDNA libraries and a genomics analysis of the brain microvasculature. Brain microvessels, combined with quantitative targeted absolute proteomics, allow for the quantitation of specific transporters or receptors expressed at the brain microvasculature. Brain microvessels, combined with specific antibodies and immune labeling of isolated capillaries, allow for the cellular location of proteins expressed within the neuro-vascular unit. Isolated brain microvessels can be used as an “in vitro” preparation of the BBB for the study of the kinetic parameters of BBB carrier-mediated transport (CMT) systems, or for the determination of dissociation constants of peptide binding to BBB receptor-mediated transport (RMT) systems expressed at either the animal or the human BBB. This review will discuss how the isolated brain microvessel model system has advanced our understanding of the organization and functional properties of the BBB, and highlight recent renewed interest in this 50 year old model of the BBB.
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Affiliation(s)
- William M Pardridge
- Department of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
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20
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Nelson AR, Sagare MA, Wang Y, Kisler K, Zhao Z, Zlokovic BV. Channelrhodopsin Excitation Contracts Brain Pericytes and Reduces Blood Flow in the Aging Mouse Brain in vivo. Front Aging Neurosci 2020; 12:108. [PMID: 32410982 PMCID: PMC7201096 DOI: 10.3389/fnagi.2020.00108] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 03/30/2020] [Indexed: 01/02/2023] Open
Abstract
Brains depend on blood flow for the delivery of oxygen and nutrients essential for proper neuronal and synaptic functioning. French physiologist Rouget was the first to describe pericytes in 1873 as regularly arranged longitudinal amoeboid cells on capillaries that have a muscular coat, implying that these are contractile cells that regulate blood flow. Although there have been >30 publications from different groups, including our group, demonstrating that pericytes are contractile cells that can regulate hemodynamic responses in the brain, the role of pericytes in controlling cerebral blood flow (CBF) has not been confirmed by all studies. Moreover, recent studies using different optogenetic models to express light-sensitive channelrhodopsin-2 (ChR2) cation channels in pericytes were not conclusive; one, suggesting that pericytes expressing ChR2 do not contract after light stimulus, and the other, demonstrating contraction of pericytes expressing ChR2 after light stimulus. Since two-photon optogenetics provides a powerful tool to study mechanisms of blood flow regulation at the level of brain capillaries, we re-examined the contractility of brain pericytes in vivo using a new optogenetic model developed by crossing our new inducible pericyte-specific CreER mouse line with ChR2 mice. We induced expression of ChR2 in pericytes with tamoxifen, excited ChR2 by 488 nm light, and monitored pericyte contractility, brain capillary diameter changes, and red blood cell (RBC) velocity in aged mice by in vivo two-photon microscopy. Excitation of ChR2 resulted in pericyte contraction followed by constriction of the underlying capillary leading to approximately an 8% decrease (p = 0.006) in capillary diameter. ChR2 excitation in pericytes substantially reduced capillary RBC flow by 42% (p = 0.03) during the stimulation period compared to the velocity before stimulation. Our data suggests that pericytes contract in vivo and regulate capillary blood flow in the aging mouse brain. By extension, this might have implications for neurological disorders of the aging human brain associated with neurovascular dysfunction and pericyte loss such as stroke and Alzheimer's disease.
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Affiliation(s)
| | | | | | | | | | - Berislav V. Zlokovic
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, University of Southern California, Los Angeles, CA, United States
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21
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Uemura MT, Maki T, Ihara M, Lee VMY, Trojanowski JQ. Brain Microvascular Pericytes in Vascular Cognitive Impairment and Dementia. Front Aging Neurosci 2020; 12:80. [PMID: 32317958 PMCID: PMC7171590 DOI: 10.3389/fnagi.2020.00080] [Citation(s) in RCA: 129] [Impact Index Per Article: 32.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 03/04/2020] [Indexed: 12/19/2022] Open
Abstract
Pericytes are unique, multi-functional mural cells localized at the abluminal side of the perivascular space in microvessels. Originally discovered in 19th century, pericytes had drawn less attention until decades ago mainly due to lack of specific markers. Recently, however, a growing body of evidence has revealed that pericytes play various important roles: development and maintenance of blood–brain barrier (BBB), regulation of the neurovascular system (e.g., vascular stability, vessel formation, cerebral blood flow, etc.), trafficking of inflammatory cells, clearance of toxic waste products from the brain, and acquisition of stem cell-like properties. In the neurovascular unit, pericytes perform these functions through coordinated crosstalk with neighboring cells including endothelial, glial, and neuronal cells. Dysfunction of pericytes contribute to a wide variety of diseases that lead to cognitive impairments such as cerebral small vessel disease (SVD), acute stroke, Alzheimer’s disease (AD), and other neurological disorders. For instance, in SVDs, pericyte degeneration leads to microvessel instability and demyelination while in stroke, pericyte constriction after ischemia causes a no-reflow phenomenon in brain capillaries. In AD, which shares some common risk factors with vascular dementia, reduction in pericyte coverage and subsequent microvascular impairments are observed in association with white matter attenuation and contribute to impaired cognition. Pericyte loss causes BBB-breakdown, which stagnates amyloid β clearance and the leakage of neurotoxic molecules into the brain parenchyma. In this review, we first summarize the characteristics of brain microvessel pericytes, and their roles in the central nervous system. Then, we focus on how dysfunctional pericytes contribute to the pathogenesis of vascular cognitive impairment including cerebral ‘small vessel’ and ‘large vessel’ diseases, as well as AD. Finally, we discuss therapeutic implications for these disorders by targeting pericytes.
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Affiliation(s)
- Maiko T Uemura
- Institute on Aging and Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States.,JSPS Overseas Research Fellowship Program, Japan Society for the Promotion of Science, Tokyo, Japan
| | - Takakuni Maki
- Department of Neurology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Masafumi Ihara
- Department of Neurology, National Cerebral and Cardiovascular Center, Osaka, Japan
| | - Virginia M Y Lee
- Institute on Aging and Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - John Q Trojanowski
- Institute on Aging and Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
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22
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Alarcon-Martinez L, Yilmaz-Ozcan S, Yemisci M, Schallek J, Kılıç K, Villafranca-Baughman D, Can A, Di Polo A, Dalkara T. Retinal ischemia induces α-SMA-mediated capillary pericyte contraction coincident with perivascular glycogen depletion. Acta Neuropathol Commun 2019; 7:134. [PMID: 31429795 PMCID: PMC6701129 DOI: 10.1186/s40478-019-0761-z] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Accepted: 06/26/2019] [Indexed: 12/21/2022] Open
Abstract
Increasing evidence indicates that pericytes are vulnerable cells, playing pathophysiological roles in various neurodegenerative processes. Microvascular pericytes contract during cerebral and coronary ischemia and do not relax after re-opening of the occluded artery, causing incomplete reperfusion. However, the cellular mechanisms underlying ischemia-induced pericyte contraction, its delayed emergence, and whether it is pharmacologically reversible are unclear. Here, we investigate i) whether ischemia-induced pericyte contractions are mediated by alpha-smooth muscle actin (α-SMA), ii) the sources of calcium rise in ischemic pericytes, and iii) if peri-microvascular glycogen can support pericyte metabolism during ischemia. Thus, we examined pericyte contractility in response to retinal ischemia both in vivo, using adaptive optics scanning light ophthalmoscopy and, ex vivo, using an unbiased stereological approach. We found that microvascular constrictions were associated with increased calcium in pericytes as detected by a genetically encoded calcium indicator (NG2-GCaMP6) or a fluoroprobe (Fluo-4). Knocking down α-SMA expression with RNA interference or fixing F-actin with phalloidin or calcium antagonist amlodipine prevented constrictions, suggesting that constrictions resulted from calcium- and α-SMA-mediated pericyte contractions. Carbenoxolone or a Cx43-selective peptide blocker also reduced calcium rise, consistent with involvement of gap junction-mediated mechanisms in addition to voltage-gated calcium channels. Pericyte calcium increase and capillary constrictions became significant after 1 h of ischemia and were coincident with depletion of peri-microvascular glycogen, suggesting that glucose derived from glycogen granules could support pericyte metabolism and delay ischemia-induced microvascular dysfunction. Indeed, capillary constrictions emerged earlier when glycogen breakdown was pharmacologically inhibited. Constrictions persisted despite recanalization but were reversible with pericyte-relaxant adenosine administered during recanalization. Our study demonstrates that retinal ischemia, a common cause of blindness, induces α-SMA- and calcium-mediated persistent pericyte contraction, which can be delayed by glucose driven from peri-microvascular glycogen. These findings clarify the contractile nature of capillary pericytes and identify a novel metabolic collaboration between peri-microvascular end-feet and pericytes.
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Affiliation(s)
- Luis Alarcon-Martinez
- Institute of Neurological Sciences and Psychiatry, Hacettepe University, Sihhiye, 06100, Ankara, Turkey
- Department of Neuroscience and Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Université de Montréal, Montréal, Québec, Canada
| | - Sinem Yilmaz-Ozcan
- Institute of Neurological Sciences and Psychiatry, Hacettepe University, Sihhiye, 06100, Ankara, Turkey
| | - Muge Yemisci
- Institute of Neurological Sciences and Psychiatry, Hacettepe University, Sihhiye, 06100, Ankara, Turkey.
- Department of Neurology, Faculty of Medicine, Hacettepe University, Ankara, Turkey.
| | - Jesse Schallek
- Flaum Eye Institute and Center for Visual Science, University of Rochester, Rochester, New York, USA
| | - Kıvılcım Kılıç
- Institute of Neurological Sciences and Psychiatry, Hacettepe University, Sihhiye, 06100, Ankara, Turkey
| | - Deborah Villafranca-Baughman
- Department of Neuroscience and Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Université de Montréal, Montréal, Québec, Canada
| | - Alp Can
- Department of Histology and Embryology, School of Medicine, Ankara University, Ankara, Turkey
| | - Adriana Di Polo
- Department of Neuroscience and Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Université de Montréal, Montréal, Québec, Canada
| | - Turgay Dalkara
- Institute of Neurological Sciences and Psychiatry, Hacettepe University, Sihhiye, 06100, Ankara, Turkey.
- Department of Neurology, Faculty of Medicine, Hacettepe University, Ankara, Turkey.
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Brown LS, Foster CG, Courtney JM, King NE, Howells DW, Sutherland BA. Pericytes and Neurovascular Function in the Healthy and Diseased Brain. Front Cell Neurosci 2019; 13:282. [PMID: 31316352 PMCID: PMC6611154 DOI: 10.3389/fncel.2019.00282] [Citation(s) in RCA: 218] [Impact Index Per Article: 43.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 06/11/2019] [Indexed: 12/11/2022] Open
Abstract
Pericytes are multi-functional cells embedded within the walls of capillaries throughout the body, including the brain. Pericytes were first identified in the 1870s, but little attention was paid to them during the following century. More recently, numerous vascular functions of pericytes have been identified including regulation of cerebral blood flow, maintenance of the blood-brain barrier (BBB), and control of vascular development and angiogenesis. Pericytes can also facilitate neuroinflammatory processes and possess stem cell-like properties. Pericytes form part of the neurovascular unit (NVU), a collection of cells that control interactions between neurons and the cerebral vasculature to meet the energy demands of the brain. Pericyte structure, expression profile, and function in the brain differ depending on their location along the vascular bed. Until recently, it has been difficult to accurately define the sub-types of pericytes, or to specifically target pericytes with pharmaceutical agents, but emerging techniques both in vitro and in vivo will improve investigation of pericytes and allow for the identification of their possible roles in diseases. Pericyte dysfunction is increasingly recognized as a contributor to the progression of vascular diseases such as stroke and neurodegenerative diseases such as Alzheimer's disease. The therapeutic potential of pericytes to repair cerebral blood vessels and promote angiogenesis due to their ability to behave like stem cells has recently been brought to light. Here, we review the history of pericyte research, the present techniques used to study pericytes in the brain, and current research advancements to characterize and therapeutically target pericytes in the future.
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Affiliation(s)
| | | | | | | | | | - Brad A. Sutherland
- School of Medicine, College of Health and Medicine, University of Tasmania, Hobart, TAS, Australia
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24
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Abstract
Recent stroke research has shifted the focus to the microvasculature from neuron-centric views. It is increasingly recognized that a successful neuroprotection is not feasible without microvascular protection. On the other hand, recent studies on pericytes, long-neglected cells on microvessels have provided insight into the regulation of microcirculation. Pericytes play an essential role in matching the metabolic demand of nervous tissue with the blood flow in addition to regulating the development and maintenance of the blood-brain barrier (BBB), leukocyte trafficking across the BBB and angiogenesis. Pericytes appears to be highly vulnerable to injury. Ischemic injury to pericytes on cerebral microvasculature unfavorably impacts the stroke-induced tissue damage and brain edema by disrupting microvascular blood flow and BBB integrity. Strongly supporting this, clinical imaging studies show that tissue reperfusion is not always obtained after recanalization. Therefore, prevention of pericyte dysfunction may improve the outcome of recanalization therapies by promoting microcirculatory reperfusion and preventing hemorrhage and edema. In the peri-infarct tissue, pericytes are detached from microvessels and promote angiogenesis and neurogenesis, and hence positively effect stroke outcome. Expectedly, we will learn more about the place of pericytes in CNS pathologies including stroke and devise approaches to treat them in the next decades.
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25
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Lee LL, Chintalgattu V. Pericytes in the Heart. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1122:187-210. [PMID: 30937870 DOI: 10.1007/978-3-030-11093-2_11] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Mural cells known as pericytes envelop the endothelial layer of microvessels throughout the body and have been described to have tissue-specific functions. Cardiac pericytes are abundantly found in the heart, but they are relatively understudied. Currently, their importance is emerging in cardiovascular homeostasis and dysfunction due to their pleiotropism. They are known to play key roles in vascular tone and vascular integrity as well as angiogenesis. However, their dysfunctional presence and/or absence is critical in the mechanisms that lead to cardiac pathologies such as myocardial infarction, fibrosis, and thrombosis. Moreover, they are targeted as a therapeutic potential due to their mesenchymal properties that could allow them to repair and regenerate a damaged heart. They are also sought after as a cell-based therapy based on their healing potential in preclinical studies of animal models of myocardial infarction. Therefore, recognizing the importance of cardiac pericytes and understanding their biology will lead to new therapeutic concepts.
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Affiliation(s)
- Linda L Lee
- Department of CardioMetabolic Disorders, Amgen Research and Discovery, Amgen Inc., South San Francisco, CA, USA
| | - Vishnu Chintalgattu
- Department of CardioMetabolic Disorders, Amgen Research and Discovery, Amgen Inc., South San Francisco, CA, USA.
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26
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Kolinko Y, Kralickova M, Tonar Z. The impact of pericytes on the brain and approaches for their morphological analysis. J Chem Neuroanat 2018; 91:35-45. [DOI: 10.1016/j.jchemneu.2018.04.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 04/10/2018] [Accepted: 04/15/2018] [Indexed: 12/15/2022]
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Abstract
Stroke is a cerebrovascular disorder that affects many people worldwide. In addition to the well-established functions of astrocytes and microglia in stroke pathogenesis, pericytes also play an important role in stroke progression and recovery. As perivascular multi-potent cells and an important component of the blood–brain barrier (BBB), pericytes have been shown to exert a large variety of functions, including serving as stem/progenitor cells and maintaining BBB integrity. Here in this review, we summarize the roles of pericytes in stroke pathogenesis, with a focus on their effects in cerebral blood flow, BBB integrity, angiogenesis, immune responses, scar formation and fibrosis.
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Affiliation(s)
- Jyoti Gautam
- 1 Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, Athens, GA, USA
| | - Yao Yao
- 1 Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, Athens, GA, USA
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28
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Yu SJ, Buerck JP, O'Rear EA, Whitsett TL. Possible erythrocyte contributions to and exacerbation of the post-thrombolytic no-reflow phenomenon. Biorheology 2018; 54:81-93. [PMID: 29332028 DOI: 10.3233/bir-17144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Reperfusion injury often occurs with therapeutic intervention addressing the arterial occlusions causing acute myocardial infarction and stroke. The no-reflow phenomenon has been ascribed to leukocyte plugging and blood vessel constriction in the microcirculation. OBJECTIVE To assess possible red cell contributions to post-thrombolytic no-reflow phenomenon. METHODS Blood clots were formed by recalcifying 1 ml of citrated fresh human venous blood and then lysed by adding 1,000 units of streptokinase (SK) at several intervals within 1 hour. Red cell deformability was tested by both a microscopic photometric and a filtration technique, viscosity by a cone and plate viscometer, and erythrocyte aggregation by an optical aggregometer. RESULTS Two sampling methods were devised for the microscopic photometric test, both of which indicated increases of erythrocyte stiffness after being lysed from the clot by SK. In accompanying experiments, the viscosity, aggregation and filterability of the post-lytic erythrocytes were assessed. Results indicated increased viscosity in Ringer's, decreased aggregation index and filterability through a 5 μm pore size Nuclepore membrane. CONCLUSION Findings demonstrated that post-lytic changes in red cell deformability do occur which could contribute to the no-reflow phenomenon.
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Affiliation(s)
- Shang-Jen Yu
- Department of Chemical, Biological and Materials Engineering, University of Oklahoma, Norman, OK 73019, USA
| | - James P Buerck
- Department of Chemical, Biological and Materials Engineering, University of Oklahoma, Norman, OK 73019, USA
| | - Edgar A O'Rear
- Department of Chemical, Biological and Materials Engineering, University of Oklahoma, Norman, OK 73019, USA
| | - Thomas L Whitsett
- Department of Medicine, University of Oklahoma Health Science Center, Oklahoma City, OK 73014, USA
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29
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Zhang JH, Obenaus A, Liebeskind DS, Tang J, Hartman R, Pearce WJ. Recanalization, reperfusion, and recirculation in stroke. J Cereb Blood Flow Metab 2017; 37:3818-3823. [PMID: 28925323 PMCID: PMC5718333 DOI: 10.1177/0271678x17732695] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Recirculation, from arterial inflow routes through venous outflow pathways, was conceptualized in stroke research 50 years ago. As new technologies were developed, blocked arteries could be reopened, capillaries could be reperfused, and the use of recanalization and reperfusion grew to dominate therapeutic strategies. These approaches overwhelmingly focused on restoration of arterial and capillary inflow, but not on veins even though venous disorders may initiate or exacerbate brain injury. In this commentary, we advance the term "recirculation" after "recanalization" and "reperfusion" as a primary concept of stroke pathophysiology that targets the restoration of both the arterial and venous cerebral circulations.
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Affiliation(s)
- John H Zhang
- 1 Center for Neuroscience Research, 4608 Loma Linda University School of Medicine, Loma Linda, CA, USA
| | - Andre Obenaus
- 1 Center for Neuroscience Research, 4608 Loma Linda University School of Medicine, Loma Linda, CA, USA
| | - David S Liebeskind
- 2 Neurovascular Imaging Research Core and Department of Neurology, UCLA, CA, USA
| | - Jiping Tang
- 1 Center for Neuroscience Research, 4608 Loma Linda University School of Medicine, Loma Linda, CA, USA
| | - Richard Hartman
- 1 Center for Neuroscience Research, 4608 Loma Linda University School of Medicine, Loma Linda, CA, USA
| | - William J Pearce
- 1 Center for Neuroscience Research, 4608 Loma Linda University School of Medicine, Loma Linda, CA, USA
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30
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Umehara K, Sun Y, Hiura S, Hamada K, Itoh M, Kitamura K, Oshima M, Iwama A, Saito K, Anzai N, Chiba K, Akita H, Furihata T. A New Conditionally Immortalized Human Fetal Brain Pericyte Cell Line: Establishment and Functional Characterization as a Promising Tool for Human Brain Pericyte Studies. Mol Neurobiol 2017; 55:5993-6006. [PMID: 29128907 DOI: 10.1007/s12035-017-0815-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Accepted: 10/27/2017] [Indexed: 12/30/2022]
Abstract
While pericytes wrap around microvascular endothelial cells throughout the human body, their highest coverage rate is found in the brain. Brain pericytes actively contribute to various brain functions, including the development and stabilization of the blood-brain barrier (BBB), tissue regeneration, and brain inflammation. Accordingly, detailed characterization of the functional nature of brain pericytes is important for understanding the mechanistic basis of brain physiology and pathophysiology. Herein, we report on the development of a new human brain pericyte cell line, hereafter referred to as the human brain pericyte/conditionally immortalized clone 37 (HBPC/ci37). Developed via the cell conditionally immortalization method, these cells exhibited excellent proliferative ability at 33 °C. However, when cultured at 37 °C, HBPC/ci37 cells showed a differentiated phenotype that was marked by morphological alterations and increases in several pericyte-enriched marker mRNA levels, such as platelet-derived growth factor receptor β. It was also found that HBPC/ci37 cells possessed the facilitative ability of in vitro BBB formation and differentiation into a neuronal lineage. Furthermore, HBPC/ci37 cells exhibited the typical "reactive" features of brain pericytes in response to pro-inflammatory cytokines. To summarize, our results clearly demonstrate that HBPC/ci37 cells possess the ability to perform several key brain pericyte functions while also showing the capacity for extensive and continuous proliferation. Based on these findings, it can be expected that, as a unique human brain pericyte model, HBPC/ci37 cells have the potential to contribute to significant advances in the understanding of human brain pericyte physiology and pathophysiology.
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Affiliation(s)
- Kenta Umehara
- Laboratory of Pharmacology and Toxicology, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, 260-8675, Japan
| | - Yuchen Sun
- Laboratory of Pharmacology and Toxicology, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, 260-8675, Japan
| | - Satoshi Hiura
- Department of Biochemistry, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, 260-8675, Japan
| | - Koki Hamada
- Department of Biochemistry, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, 260-8675, Japan
| | - Motoyuki Itoh
- Department of Biochemistry, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, 260-8675, Japan
| | - Keita Kitamura
- Laboratory of Pharmacology and Toxicology, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, 260-8675, Japan
| | - Motohiko Oshima
- Department of Cellular and Molecular Medicine, Graduate School of Medicine, Chiba University, Chiba, 260-8670, Japan
| | - Atsushi Iwama
- Department of Cellular and Molecular Medicine, Graduate School of Medicine, Chiba University, Chiba, 260-8670, Japan
| | - Kosuke Saito
- Laboratory of Pharmacology and Toxicology, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, 260-8675, Japan
- Division of Medical Safety Science, National Institute of Health Sciences, Tokyo, 158-8501, Japan
| | - Naohiko Anzai
- Department of Pharmacology, Graduate School of Medicine, Chiba University, Chiba, 260-8670, Japan
| | - Kan Chiba
- Laboratory of Pharmacology and Toxicology, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, 260-8675, Japan
| | - Hidetaka Akita
- Laboratory of Pharmacology and Toxicology, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, 260-8675, Japan
| | - Tomomi Furihata
- Laboratory of Pharmacology and Toxicology, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, 260-8675, Japan.
- Department of Pharmacology, Graduate School of Medicine, Chiba University, Chiba, 260-8670, Japan.
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Oxidative stress and DNA damage after cerebral ischemia: Potential therapeutic targets to repair the genome and improve stroke recovery. Neuropharmacology 2017; 134:208-217. [PMID: 29128308 DOI: 10.1016/j.neuropharm.2017.11.011] [Citation(s) in RCA: 183] [Impact Index Per Article: 26.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 11/02/2017] [Accepted: 11/05/2017] [Indexed: 12/12/2022]
Abstract
The past two decades have witnessed remarkable advances in oxidative stress research, particularly in the context of ischemic brain injury. Oxidative stress in ischemic tissues compromises the integrity of the genome, resulting in DNA lesions, cell death in neurons, glial cells, and vascular cells, and impairments in neurological recovery after stroke. As DNA is particularly vulnerable to oxidative attack, cells have evolved the ability to induce multiple DNA repair mechanisms, including base excision repair (BER), nucleotide excision repair (NER) and non-homogenous endpoint jointing (NHEJ). Defective DNA repair is tightly correlated with worse neurological outcomes after stroke, whereas upregulation of DNA repair enzymes, such as APE1, OGG1, and XRCC1, improves long-term functional recovery following stroke. Indeed, DNA damage and repair are now known to play critical roles in fundamental aspects of stroke recovery, such as neurogenesis, white matter recovery, and neurovascular unit remodeling. Several DNA repair enzymes are essential for comprehensive neural repair mechanisms after stroke, including Polβ and NEIL3 for neurogenesis, APE1 for white matter repair, Gadd45b for axonal regeneration, and DNA-PKs for neurovascular remodeling. This review discusses the emerging role of DNA damage and repair in functional recovery after stroke and highlights the contribution of DNA repair to regenerative elements after stroke. This article is part of the Special Issue entitled 'Cerebral Ischemia'.
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32
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Kisler K, Nelson AR, Montagne A, Zlokovic BV. Cerebral blood flow regulation and neurovascular dysfunction in Alzheimer disease. Nat Rev Neurosci 2017; 18:419-434. [PMID: 28515434 PMCID: PMC5759779 DOI: 10.1038/nrn.2017.48] [Citation(s) in RCA: 756] [Impact Index Per Article: 108.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Cerebral blood flow (CBF) regulation is essential for normal brain function. The mammalian brain has evolved a unique mechanism for CBF control known as neurovascular coupling. This mechanism ensures a rapid increase in the rate of CBF and oxygen delivery to activated brain structures. The neurovascular unit is composed of astrocytes, mural vascular smooth muscle cells and pericytes, and endothelia, and regulates neurovascular coupling. This Review article examines the cellular and molecular mechanisms within the neurovascular unit that contribute to CBF control, and neurovascular dysfunction in neurodegenerative disorders such as Alzheimer disease.
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Affiliation(s)
- Kassandra Kisler
- Zilkha Neurogenetic Institute, 1501 San Pablo Street, Los Angeles, California 90089, USA
| | - Amy R Nelson
- Zilkha Neurogenetic Institute, 1501 San Pablo Street, Los Angeles, California 90089, USA
| | - Axel Montagne
- Zilkha Neurogenetic Institute, 1501 San Pablo Street, Los Angeles, California 90089, USA
| | - Berislav V Zlokovic
- Zilkha Neurogenetic Institute, 1501 San Pablo Street, Los Angeles, California 90089, USA
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Strand TE, Khiabani HZ, Boico A, Radiloff D, Zhao Y, Hamilton KL, Christians U, Klawitter J, Noveck RJ, Piantadosi CA, Bell C, Irwin D, Schroeder T. The novel combination of theophylline and bambuterol as a potential treatment of hypoxemia in humans. Can J Physiol Pharmacol 2017; 95:1009-1018. [PMID: 28467859 DOI: 10.1139/cjpp-2016-0635] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Hypoxemia can be life-threatening, both acutely and chronically. Because hypoxemia causes vascular dysregulation that further restricts oxygen availability to tissue, it can be pharmacologically addressed. We hypothesized that theophylline can be safely combined with the β2-adrenergic vasodilator bambuterol to improve oxygen availability in hypoxemic patients. Ergogenicity and hemodynamic effects of bambuterol and theophylline were measured in rats under hypobaric and normobaric hypoxia (12% O2). Feasibility in humans was assessed using randomized, double-blind testing of the influence of combined slow-release theophylline (300 mg) and bambuterol (20 mg) on adverse events (AEs), plasma K+, pulse, blood pressure, and drug interaction. Both drugs and their combination significantly improved hypoxic endurance in rats. In humans, common AEs were low K+ (<3.5 mmol/L; bambuterol: 12, theophylline: 4, combination: 13 episodes) and tremors (10, 0, 14 episodes). No exacerbation or serious AE occurred when drugs were combined. A drop in plasma K+ coincided with peak bambuterol plasma concentrations. Bambuterol increased heart rate by approximately 13 bpm. Drug interaction was present but small. We report promise, feasibility, and relative safety of combined theophylline and bambuterol as a treatment of hypoxemia in humans. Cardiac safety and blood K+ will be important safety endpoints when testing these drugs in hypoxemic subjects.
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Affiliation(s)
- Trond-Eirik Strand
- a Norwegian Armed Forces Medical Services, Institute of Aviation Medicine, 0313 Oslo, Norway
| | - Hasse Z Khiabani
- b Department of Pharmacology, Oslo University Hospital, Rikshospitalet, 0372 Oslo, Norway
| | - Alina Boico
- c Department of Radiation Oncology, Duke University Medical Center, Durham, NC 27710, USA
| | | | - Yulin Zhao
- c Department of Radiation Oncology, Duke University Medical Center, Durham, NC 27710, USA
| | - Karyn L Hamilton
- e Department of Health and Exercise Science, Colorado State University, Fort Collins, CO 80523, USA
| | - Uwe Christians
- f iC42 Integrated Solutions in Clinical Research and Development, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Jelena Klawitter
- f iC42 Integrated Solutions in Clinical Research and Development, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Robert J Noveck
- g Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | | | - Christopher Bell
- e Department of Health and Exercise Science, Colorado State University, Fort Collins, CO 80523, USA
| | - David Irwin
- i Department of Medicine, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Thies Schroeder
- i Department of Medicine, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO 80045, USA.,j Department of Biochemistry and Pharmacology, University of Mainz, 55128 Mainz, Germany
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