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Korte N, James G, You H, Hirunpattarasilp C, Christie I, Sethi H, Attwell D. Noradrenaline released from locus coeruleus axons contracts cerebral capillary pericytes via α2 adrenergic receptors. J Cereb Blood Flow Metab 2023; 43:1142-1152. [PMID: 36688515 PMCID: PMC10291462 DOI: 10.1177/0271678x231152549] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 11/15/2022] [Accepted: 01/03/2023] [Indexed: 01/24/2023]
Abstract
Noradrenaline (NA) release from locus coeruleus axons generates vascular contractile tone in arteriolar smooth muscle and contractile capillary pericytes. This tone allows neuronal activity to evoke vasodilation that increases local cerebral blood flow (CBF). Much of the vascular resistance within the brain is located in capillaries and locus coeruleus axons have NA release sites closer to pericytes than to arterioles. In acute brain slices, NA contracted pericytes but did not raise the pericyte cytoplasmic Ca2+ concentration, while the α1 agonist phenylephrine did not evoke contraction. Blocking α2 adrenergic receptors (α2Rs, which induce contraction by inhibiting cAMP production), greatly reduced the NA-evoked pericyte contraction, whereas stimulating α2Rs using xylazine (a sedative) or clonidine (an anti-hypertensive drug) evoked pericyte contraction. Noradrenaline-evoked pericyte contraction and capillary constriction are thus mediated via α2Rs. Consequently, α2Rs may not only modulate CBF in health and pathological conditions, but also contribute to CBF changes evoked by α2R ligands administered in research, veterinary and clinical settings.
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Affiliation(s)
- Nils Korte
- Dept of Neuroscience, Physiology & Pharmacology, University College London, London, UK
| | - Greg James
- Dept of Neuroscience, Physiology & Pharmacology, University College London, London, UK
- Department of Neurosurgery, Great Ormond Street Hospital, London, UK
| | - Haoming You
- Dept of Neuroscience, Physiology & Pharmacology, University College London, London, UK
| | - Chanawee Hirunpattarasilp
- Dept of Neuroscience, Physiology & Pharmacology, University College London, London, UK
- Princess Srisavangavadhana College of Medicine, Chulabhorn Royal Academy, Bangkok, Thailand
| | - Isabel Christie
- Dept of Neuroscience, Physiology & Pharmacology, University College London, London, UK
| | - Huma Sethi
- Dept of Neurosurgery, National Hospital for Neurology and Neurosurgery, London, UK
| | - David Attwell
- Dept of Neuroscience, Physiology & Pharmacology, University College London, London, UK
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Barkaway A, Attwell D, Korte N. Immune-vascular mural cell interactions: consequences for immune cell trafficking, cerebral blood flow, and the blood-brain barrier. Neurophotonics 2022; 9:031914. [PMID: 35581998 PMCID: PMC9107322 DOI: 10.1117/1.nph.9.3.031914] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 04/13/2022] [Indexed: 06/15/2023]
Abstract
Brain barriers are crucial sites for cerebral energy supply, waste removal, immune cell migration, and solute exchange, all of which maintain an appropriate environment for neuronal activity. At the capillary level, where the largest area of brain-vascular interface occurs, pericytes adjust cerebral blood flow (CBF) by regulating capillary diameter and maintain the blood-brain barrier (BBB) by suppressing endothelial cell (EC) transcytosis and inducing tight junction expression between ECs. Pericytes also limit the infiltration of circulating leukocytes into the brain where resident microglia confine brain injury and provide the first line of defence against invading pathogens. Brain "waste" is cleared across the BBB into the blood, phagocytosed by microglia and astrocytes, or removed by the flow of cerebrospinal fluid (CSF) through perivascular routes-a process driven by respiratory motion and the pulsation of the heart, arteriolar smooth muscle, and possibly pericytes. "Dirty" CSF exits the brain and is probably drained around olfactory nerve rootlets and via the dural meningeal lymphatic vessels and possibly the skull bone marrow. The brain is widely regarded as an immune-privileged organ because it is accessible to few antigen-primed leukocytes. Leukocytes enter the brain via the meninges, the BBB, and the blood-CSF barrier. Advances in genetic and imaging tools have revealed that neurological diseases significantly alter immune-brain barrier interactions in at least three ways: (1) the brain's immune-privileged status is compromised when pericytes are lost or lymphatic vessels are dysregulated; (2) immune cells release vasoactive molecules to regulate CBF, modulate arteriole stiffness, and can plug and eliminate capillaries which impairs CBF and possibly waste clearance; and (3) immune-vascular interactions can make the BBB leaky via multiple mechanisms, thus aggravating the influx of undesirable substances and cells. Here, we review developments in these three areas and briefly discuss potential therapeutic avenues for restoring brain barrier functions.
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Affiliation(s)
- Anna Barkaway
- University College London, Department of Neuroscience, Physiology and Pharmacology, London, United Kingdom
| | - David Attwell
- University College London, Department of Neuroscience, Physiology and Pharmacology, London, United Kingdom
| | - Nils Korte
- University College London, Department of Neuroscience, Physiology and Pharmacology, London, United Kingdom
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Korte N, Ilkan Z, Pearson CL, Pfeiffer T, Singhal P, Rock JR, Sethi H, Gill D, Attwell D, Tammaro P. The Ca2+-gated channel TMEM16A amplifies capillary pericyte contraction and reduces cerebral blood flow after ischemia. J Clin Invest 2022; 132:e154118. [PMID: 35316222 PMCID: PMC9057602 DOI: 10.1172/jci154118] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Accepted: 03/16/2022] [Indexed: 11/26/2022] Open
Abstract
Pericyte-mediated capillary constriction decreases cerebral blood flow in stroke after an occluded artery is unblocked. The determinants of pericyte tone are poorly understood. We show that a small rise in cytoplasmic Ca2+ concentration ([Ca2+]i) in pericytes activated chloride efflux through the Ca2+-gated anion channel TMEM16A, thus depolarizing the cell and opening voltage-gated calcium channels. This mechanism strongly amplified the pericyte [Ca2+]i rise and capillary constriction evoked by contractile agonists and ischemia. In a rodent stroke model, TMEM16A inhibition slowed the ischemia-evoked pericyte [Ca2+]i rise, capillary constriction, and pericyte death; reduced neutrophil stalling; and improved cerebrovascular reperfusion. Genetic analysis implicated altered TMEM16A expression in poor patient recovery from ischemic stroke. Thus, pericyte TMEM16A is a crucial regulator of cerebral capillary function and a potential therapeutic target for stroke and possibly other disorders of impaired microvascular flow, such as Alzheimer's disease and vascular dementia.
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Affiliation(s)
- Nils Korte
- Department of Neuroscience, Physiology & Pharmacology, University College London, London, United Kingdom
| | - Zeki Ilkan
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
| | - Claire L. Pearson
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
| | - Thomas Pfeiffer
- Department of Neuroscience, Physiology & Pharmacology, University College London, London, United Kingdom
| | - Prabhav Singhal
- Department of Neuroscience, Physiology & Pharmacology, University College London, London, United Kingdom
| | - Jason R. Rock
- Center for Regenerative Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Huma Sethi
- Department of Neurosurgery, National Hospital for Neurology and Neurosurgery, London, United Kingdom
| | - Dipender Gill
- Department of Epidemiology and Biostatistics, St Mary’s Hospital, Imperial College London, London, United Kingdom
| | - David Attwell
- Department of Neuroscience, Physiology & Pharmacology, University College London, London, United Kingdom
| | - Paolo Tammaro
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
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Prakash P, Jethava KP, Korte N, Izquierdo P, Favuzzi E, Rose IVL, Guttenplan KA, Manchanda P, Dutta S, Rochet JC, Fishell G, Liddelow SA, Attwell D, Chopra G. Monitoring phagocytic uptake of amyloid β into glial cell lysosomes in real time. Chem Sci 2021; 12:10901-10918. [PMID: 34476070 PMCID: PMC8372545 DOI: 10.1039/d1sc03486c] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Accepted: 07/07/2021] [Indexed: 12/30/2022] Open
Abstract
Phagocytosis by glial cells is essential to regulate brain function during health and disease. Therapies for Alzheimer's disease (AD) have primarily focused on targeting antibodies to amyloid β (Aβ) or inhibitng enzymes that make it, and while removal of Aβ by phagocytosis is protective early in AD it remains poorly understood. Impaired phagocytic function of glial cells during later stages of AD likely contributes to worsened disease outcome, but the underlying mechanisms of how this occurs remain unknown. We have developed a human Aβ1-42 analogue (AβpH) that exhibits green fluorescence upon internalization into the acidic organelles of cells but is non-fluorescent at physiological pH. This allowed us to image, for the first time, glial uptake of AβpH in real time in live animals. We find that microglia phagocytose more AβpH than astrocytes in culture, in brain slices and in vivo. AβpH can be used to investigate the phagocytic mechanisms responsible for removing Aβ from the extracellular space, and thus could become a useful tool to study Aβ clearance at different stages of AD.
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Affiliation(s)
- Priya Prakash
- Department of Chemistry, Purdue University West Lafayette IN 47907 USA
| | - Krupal P Jethava
- Department of Chemistry, Purdue University West Lafayette IN 47907 USA
| | - Nils Korte
- Department of Neuroscience, Physiology and Pharmacology, University College London London WC1E 6BT UK
| | - Pablo Izquierdo
- Department of Neuroscience, Physiology and Pharmacology, University College London London WC1E 6BT UK
| | - Emilia Favuzzi
- Department of Neurobiology, Harvard Medical School 220 Longwood Avenue Boston MA 02115 USA
- Stanley Center at the Broad 75 Ames Street Cambridge MA 02142 USA
| | - Indigo V L Rose
- Neuroscience Institute, NYU Grossman School of Medicine New York NY 10016 USA
| | | | - Palak Manchanda
- Department of Chemistry, Purdue University West Lafayette IN 47907 USA
| | - Sayan Dutta
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University West Lafayette IN 47907 USA
| | - Jean-Christophe Rochet
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University West Lafayette IN 47907 USA
- Purdue Institute for Integrative Neuroscience, Purdue University West Lafayette IN 47907 USA
| | - Gord Fishell
- Department of Neurobiology, Harvard Medical School 220 Longwood Avenue Boston MA 02115 USA
- Stanley Center at the Broad 75 Ames Street Cambridge MA 02142 USA
| | - Shane A Liddelow
- Neuroscience Institute, NYU Grossman School of Medicine New York NY 10016 USA
- Department of Neuroscience & Physiology, NYU Grossman School of Medicine New York NY 10016 USA
- Department of Ophthalmology, NYU Grossman School of Medicine New York NY 10016 USA
| | - David Attwell
- Department of Neuroscience, Physiology and Pharmacology, University College London London WC1E 6BT UK
| | - Gaurav Chopra
- Department of Chemistry, Purdue University West Lafayette IN 47907 USA
- Purdue Institute for Integrative Neuroscience, Purdue University West Lafayette IN 47907 USA
- Purdue Institute for Drug Discovery 720 Clinic Drive West Lafayette IN 47907 USA
- Purdue Center for Cancer Research, Purdue University West Lafayette IN 47907 USA
- Purdue Institute of Inflammation, Immunology and Infectious Disease, Purdue University West Lafayette IN 47907 USA
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Nizari S, Basalay M, Chapman P, Korte N, Korsak A, Christie IN, Theparambil SM, Davidson SM, Reimann F, Trapp S, Yellon DM, Gourine AV. Glucagon-like peptide-1 (GLP-1) receptor activation dilates cerebral arterioles, increases cerebral blood flow, and mediates remote (pre)conditioning neuroprotection against ischaemic stroke. Basic Res Cardiol 2021; 116:32. [PMID: 33942194 PMCID: PMC8093159 DOI: 10.1007/s00395-021-00873-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 04/22/2021] [Indexed: 12/12/2022]
Abstract
Stroke remains one of the most common causes of death and disability worldwide. Several preclinical studies demonstrated that the brain can be effectively protected against ischaemic stroke by two seemingly distinct treatments: remote ischaemic conditioning (RIC), involving cycles of ischaemia/reperfusion applied to a peripheral organ or tissue, or by systemic administration of glucagon-like-peptide-1 (GLP-1) receptor (GLP-1R) agonists. The mechanisms underlying RIC- and GLP-1-induced neuroprotection are not completely understood. In this study, we tested the hypothesis that GLP-1 mediates neuroprotection induced by RIC and investigated the effect of GLP-1R activation on cerebral blood vessels, as a potential mechanism of GLP-1-induced protection against ischaemic stroke. A rat model of ischaemic stroke (90 min of middle cerebral artery occlusion followed by 24-h reperfusion) was used. RIC was induced by 4 cycles of 5 min left hind limb ischaemia interleaved with 5-min reperfusion periods. RIC markedly (by ~ 80%) reduced the cerebral infarct size and improved the neurological score. The neuroprotection established by RIC was abolished by systemic blockade of GLP-1R with a specific antagonist Exendin(9-39). In the cerebral cortex of GLP-1R reporter mice, ~ 70% of cortical arterioles displayed GLP-1R expression. In acute brain slices of the rat cerebral cortex, activation of GLP-1R with an agonist Exendin-4 had a strong dilatory effect on cortical arterioles and effectively reversed arteriolar constrictions induced by metabolite lactate or oxygen and glucose deprivation, as an ex vivo model of ischaemic stroke. In anaesthetised rats, Exendin-4 induced lasting increases in brain tissue PO2, indicative of increased cerebral blood flow. These results demonstrate that neuroprotection against ischaemic stroke established by remote ischaemic conditioning is mediated by a mechanism involving GLP-1R signalling. Potent dilatory effect of GLP-1R activation on cortical arterioles suggests that the neuroprotection in this model is mediated via modulation of cerebral blood flow and improved brain perfusion.
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Affiliation(s)
- Shereen Nizari
- Centre for Cardiovascular and Metabolic Neuroscience, Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Marina Basalay
- The Hatter Cardiovascular Institute, University College London, London, WC1E 6HX, UK
| | - Philippa Chapman
- Centre for Cardiovascular and Metabolic Neuroscience, Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Nils Korte
- Centre for Cardiovascular and Metabolic Neuroscience, Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Alla Korsak
- Centre for Cardiovascular and Metabolic Neuroscience, Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Isabel N Christie
- Centre for Cardiovascular and Metabolic Neuroscience, Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Shefeeq M Theparambil
- Centre for Cardiovascular and Metabolic Neuroscience, Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Sean M Davidson
- The Hatter Cardiovascular Institute, University College London, London, WC1E 6HX, UK
| | - Frank Reimann
- Wellcome Trust/MRC Institute of Metabolic Science, University of Cambridge, Cambridge, UK
| | - Stefan Trapp
- Centre for Cardiovascular and Metabolic Neuroscience, Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Derek M Yellon
- The Hatter Cardiovascular Institute, University College London, London, WC1E 6HX, UK
| | - Alexander V Gourine
- Centre for Cardiovascular and Metabolic Neuroscience, Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK.
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6
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Korte N, Nortley R, Attwell D. Cerebral blood flow decrease as an early pathological mechanism in Alzheimer's disease. Acta Neuropathol 2020; 140:793-810. [PMID: 32865691 PMCID: PMC7666276 DOI: 10.1007/s00401-020-02215-w] [Citation(s) in RCA: 122] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 08/15/2020] [Accepted: 08/15/2020] [Indexed: 02/08/2023]
Abstract
Therapies targeting late events in Alzheimer's disease (AD), including aggregation of amyloid beta (Aβ) and hyperphosphorylated tau, have largely failed, probably because they are given after significant neuronal damage has occurred. Biomarkers suggest that the earliest event in AD is a decrease of cerebral blood flow (CBF). This is caused by constriction of capillaries by contractile pericytes, probably evoked by oligomeric Aβ. CBF is also reduced by neutrophil trapping in capillaries and clot formation, perhaps secondary to the capillary constriction. The fall in CBF potentiates neurodegeneration by upregulating the BACE1 enzyme that makes Aβ and by promoting tau hyperphosphorylation. Surprisingly, therefore, CBF reduction may play a crucial role in driving cognitive decline by initiating the amyloid cascade itself, or being caused by and amplifying Aβ production. Here, we review developments in this area that are neglected in current approaches to AD, with the aim of promoting novel mechanism-based therapeutic approaches.
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Affiliation(s)
- Nils Korte
- Department of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Ross Nortley
- Department of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK
| | - David Attwell
- Department of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK.
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Nortley R, Korte N, Izquierdo P, Hirunpattarasilp C, Mishra A, Jaunmuktane Z, Kyrargyri V, Pfeiffer T, Khennouf L, Madry C, Gong H, Richard-Loendt A, Huang W, Saito T, Saido TC, Brandner S, Sethi H, Attwell D. Amyloid β oligomers constrict human capillaries in Alzheimer's disease via signaling to pericytes. Science 2019; 365:science.aav9518. [PMID: 31221773 DOI: 10.1126/science.aav9518] [Citation(s) in RCA: 366] [Impact Index Per Article: 73.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 04/10/2019] [Accepted: 06/04/2019] [Indexed: 12/17/2022]
Abstract
Cerebral blood flow is reduced early in the onset of Alzheimer's disease (AD). Because most of the vascular resistance within the brain is in capillaries, this could reflect dysfunction of contractile pericytes on capillary walls. We used live and rapidly fixed biopsied human tissue to establish disease relevance, and rodent experiments to define mechanism. We found that in humans with cognitive decline, amyloid β (Aβ) constricts brain capillaries at pericyte locations. This was caused by Aβ generating reactive oxygen species, which evoked the release of endothelin-1 (ET) that activated pericyte ETA receptors. Capillary, but not arteriole, constriction also occurred in vivo in a mouse model of AD. Thus, inhibiting the capillary constriction caused by Aβ could potentially reduce energy lack and neurodegeneration in AD.
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Affiliation(s)
- Ross Nortley
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Nils Korte
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Pablo Izquierdo
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Chanawee Hirunpattarasilp
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Anusha Mishra
- Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Zane Jaunmuktane
- Division of Neuropathology, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK.,Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Vasiliki Kyrargyri
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Thomas Pfeiffer
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Lila Khennouf
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Christian Madry
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Hui Gong
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Angela Richard-Loendt
- Division of Neuropathology, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
| | - Wenhui Huang
- Molecular Physiology, CIPMM, University of Saarland, D-66421 Homburg, Germany
| | - Takashi Saito
- Laboratory for Proteolytic Neuroscience, RIKEN Centre for Brain Science, Wako, Saitama 351-0198, Japan
| | - Takaomi C Saido
- Laboratory for Proteolytic Neuroscience, RIKEN Centre for Brain Science, Wako, Saitama 351-0198, Japan
| | - Sebastian Brandner
- Division of Neuropathology, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK.,Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Huma Sethi
- Division of Neurosurgery, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - David Attwell
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK.
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Isasi E, Korte N, Abudara V, Attwell D, Olivera-Bravo S. Glutaric Acid Affects Pericyte Contractility and Migration: Possible Implications for GA-I Pathogenesis. Mol Neurobiol 2019; 56:7694-7707. [DOI: 10.1007/s12035-019-1620-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 04/23/2019] [Indexed: 01/23/2023]
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Cheng J, Korte N, Nortley R, Sethi H, Tang Y, Attwell D. Targeting pericytes for therapeutic approaches to neurological disorders. Acta Neuropathol 2018; 136:507-523. [PMID: 30097696 PMCID: PMC6132947 DOI: 10.1007/s00401-018-1893-0] [Citation(s) in RCA: 140] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 07/30/2018] [Accepted: 07/31/2018] [Indexed: 12/13/2022]
Abstract
Many central nervous system diseases currently lack effective treatment and are often associated with defects in microvascular function, including a failure to match the energy supplied by the blood to the energy used on neuronal computation, or a breakdown of the blood–brain barrier. Pericytes, an under-studied cell type located on capillaries, are of crucial importance in regulating diverse microvascular functions, such as angiogenesis, the blood–brain barrier, capillary blood flow and the movement of immune cells into the brain. They also form part of the “glial” scar isolating damaged parts of the CNS, and may have stem cell-like properties. Recent studies have suggested that pericytes play a crucial role in neurological diseases, and are thus a therapeutic target in disorders as diverse as stroke, traumatic brain injury, migraine, epilepsy, spinal cord injury, diabetes, Huntington’s disease, Alzheimer’s disease, diabetes, multiple sclerosis, glioma, radiation necrosis and amyotrophic lateral sclerosis. Here we report recent advances in our understanding of pericyte biology and discuss how pericytes could be targeted to develop novel therapeutic approaches to neurological disorders, by increasing blood flow, preserving blood–brain barrier function, regulating immune cell entry to the CNS, and modulating formation of blood vessels in, and the glial scar around, damaged regions.
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Affiliation(s)
- Jinping Cheng
- Department of Neurology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, 107 Yan Jiang Xi Rd, Guangzhou, 510120, People's Republic of China
| | - Nils Korte
- Department of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Ross Nortley
- Department of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Huma Sethi
- Department of Neurosurgery, National Hospital for Neurology and Neurosurgery, Queen Square, London, WC1N 3BG, UK
| | - Yamei Tang
- Department of Neurology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, 107 Yan Jiang Xi Rd, Guangzhou, 510120, People's Republic of China.
| | - David Attwell
- Department of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK.
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Liu Y, Antonic A, Yang X, Korte N, Lim K, Michalska AE, Dottori M, Howells DW. Derivation of phenotypically diverse neural culture from hESC by combining adherent and dissociation methods. J Neurosci Methods 2018; 308:286-293. [PMID: 30003885 DOI: 10.1016/j.jneumeth.2018.07.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2018] [Revised: 07/05/2018] [Accepted: 07/05/2018] [Indexed: 11/18/2022]
Abstract
BACKGROUND Differentiation of human embryonic stem cells (hESCs) into distinct neural lineages has been widely studied. However, preparation of mixed yet neurochemically mature populations, for the study of neurological diseases involving mixed cell types has received less attention. NEW METHOD We combined two commonly used differentiation methods to provide robust and reproducible cultures in which a mixture of primarily GABAergic and Glutamatergic neurons was obtained. Detailed characterisation by immunocytochemistry (ICC) and quantitative real-time PCR (qPCR) assessed the neurochemical phenotype, and the maturation state of these neurons. RESULTS We found that once neurospheres (NSs) had attached to the culture plates, proliferation of neural stem cell was suppressed. Neuronal differentiation and synaptic development then occurred after 21 days in vitro (DIV). By 49DIV, there were large numbers of neurochemically and structurally mature neurons. The qPCR studies indicated that expression of GABAergic genes increased the most (93.3-fold increase), followed by glutamatergic (51-fold increase), along with smaller changes in expression of cholinergic (3-fold increase) and dopaminergic genes (6-fold increase), as well as a small change in glial cell marker expression (5-fold increase). COMPARISON WITH EXISTING METHOD (S) Existing methods isolate hESC-derived neural progenitors for onward differentiation to mature neurons using either migration or dissociative paradigms. These give poor survival or yield. By combining these approaches, we obtain high yields of morphologically and neurochemically mature neurons. These can be maintained in culture for extended periods. CONCLUSION Our method provides a novel, effective and robust neural culture system with structurally and neurochemically mature cell populations and neural networks, suitable for studying a range of neurological diseases from a human perspective.
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Affiliation(s)
- Ye Liu
- Florey Institute of Neuroscience and Mental Health, 30 Royal Parade, The University of Melbourne, Victoria, 3010, Australia; Department of Neurology, Fudan University, Huashan Hospital, Shanghai, 200040, China
| | - Ana Antonic
- Department of Neuroscience, Central Clinical School, Monash University, The Alfred Centre, VIC, 3004, Australia
| | - Xuan Yang
- Institute for Geriatrics and Rehabilitation, Beijing Geriatric Hospital, Beijing, 100095, China
| | - Nils Korte
- Department of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London, WC1E6BT, UK
| | - Katherine Lim
- Stem Cell Core Facility, Stem Cells Australia, The University of Melbourne, Victoria, 3010, Australia
| | - Anna E Michalska
- Stem Cell Core Facility, Stem Cells Australia, The University of Melbourne, Victoria, 3010, Australia
| | - Mirella Dottori
- Illawarra Health and Medical Research Institute Centre for Molecular and Medical Bioscience Building 32, University of Wollongong, NSW, 2522 Australia
| | - David W Howells
- School of Medicine, University of Tasmania, Hobart, Tasmania, 7001, Australia.
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Korte N, Porembski S. A morpho-anatomical characterisation of Myrothamnus moschatus (Myrothamnaceae) under the aspect of desiccation tolerance. Plant Biol (Stuttg) 2012; 14:537-541. [PMID: 22300275 DOI: 10.1111/j.1438-8677.2011.00546.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Morpho-anatomical traits of the rarely studied dicotyledonous desiccation-tolerant shrub Myrothamnus moschatus were examined and compared for the first time to Myrothamnus flabellifolius under the aspect of desiccation tolerance. Both species almost exclusively occur on rock outcrops and differ mainly in their geographic range and leaf morphology (fan-shaped in M. flabellifolius, lanceolate in M. moschatus) but have a very similar leaf and wood anatomy, except for the lack of hydathodes in M. moschatus. Both species adopt the parallel leaf venation of monocots, although this is more pronounced in M. moschatus. This provides a mechanical and protective advantage over the net venation pattern of most dicots and facilitates the reversible, drought-induced, accordion-like leaf contraction. The sclerenchyma, as a stabilising tissue, is mainly confined to vascular bundles in leaves of both species. Here, mechanical support seems to be less crucial for survival in long periods of drought than other morpho-anatomical traits (e.g. parallel leaf venation).
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Affiliation(s)
- N Korte
- Department of Botany, Institute of Biological Sciences, University of Rostock, Rostock, Germany.
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Grittini C, Malcomson M, Fernando Q, Korte N. Rapid dechlorination of polychlorinated biphenyls on the surface of a pd/fe bimetallic system. Environ Sci Technol 1995; 29:2898-2900. [PMID: 22206541 DOI: 10.1021/es00011a029] [Citation(s) in RCA: 119] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
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Abstract
Three types of soil-gas surveys were performed over the same location at an industrial facility. The surveys performed were (1) a passive technique using buried collectors, (2) an active technique in which samples were collected in the field by pumping with subsequent analysis at a field laboratory, and (3) a screening technique that employed a hand-held survey instrument. Each of the surveys had desirable features, but there was considerable variability in the quality of data obtained, cost, and ease of performance. The passive and active surveys provided excellent detection limits, but the passive technique does not provide data in real time. The active survey was also time-consuming and required an analytical chemist in the field. Neither the active nor the passive survey were able to delineate the plume of contaminated groundwater. Consequently, the results from the rapid and inexpensive reconnaissance technique provided functionally equivalent data.
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Affiliation(s)
- N Korte
- Environmental Sciences Division, Oak Ridge National Laboratory, 81502, Grand Junction, CO, USA
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