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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: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [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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Zielinski MR, Gibbons AJ. Neuroinflammation, Sleep, and Circadian Rhythms. Front Cell Infect Microbiol 2022; 12:853096. [PMID: 35392608 PMCID: PMC8981587 DOI: 10.3389/fcimb.2022.853096] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 02/24/2022] [Indexed: 12/14/2022] Open
Abstract
Molecules involved in innate immunity affect sleep and circadian oscillators and vice versa. Sleep-inducing inflammatory molecules are activated by increased waking activity and pathogens. Pathologies that alter inflammatory molecules, such as traumatic brain injury, cancer, cardiovascular disease, and stroke often are associated with disturbed sleep and electroencephalogram power spectra. Moreover, sleep disorders, such as insomnia and sleep disordered breathing, are associated with increased dysregulation of inflammatory processes. Inflammatory molecules in both the central nervous system and periphery can alter sleep. Inflammation can also modulate cerebral vascular hemodynamics which is associated with alterations in electroencephalogram power spectra. However, further research is needed to determine the interactions of sleep regulatory inflammatory molecules and circadian clocks. The purpose of this review is to: 1) describe the role of the inflammatory cytokines interleukin-1 beta and tumor necrosis factor-alpha and nucleotide-binding domain and leucine-rich repeat protein-3 inflammasomes in sleep regulation, 2) to discuss the relationship between the vagus nerve in translating inflammatory signals between the periphery and central nervous system to alter sleep, and 3) to present information about the relationship between cerebral vascular hemodynamics and the electroencephalogram during sleep.
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Affiliation(s)
- Mark R. Zielinski
- Veterans Affairs (VA) Boston Healthcare System, West Roxbury, MA, United States,Harvard Medical School, West Roxbury, MA, United States,*Correspondence: Mark R. Zielinski,
| | - Allison J. Gibbons
- Veterans Affairs (VA) Boston Healthcare System, West Roxbury, MA, United States
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3
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Walrand S, Gaulmin R, Aubin R, Sapin V, Coste A, Abbot M. Nutritional factors in sport-related concussion. Neurochirurgie 2021; 67:255-258. [PMID: 33582206 DOI: 10.1016/j.neuchi.2021.02.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 02/06/2021] [Indexed: 11/28/2022]
Abstract
BACKGROUND Sports concussion is a major problem that affects thousands of people every year. Concussion-related neurometabolic changes are thought to underlie neurophysiological alterations and post-concussion symptoms, such as headaches and sensitivity to light and noise, disabilities of concentration and tiredness. The injury triggers a complex neurometabolic cascade involving multiple mechanisms. There are pharmaceutical treatments that target one mechanism, but specific nutrients have been found to impact several pathways, thus offering a broader approach. This has prompted intensive research into the use of nutrient supplements as a concussion prevention and treatment strategy. METHOD We realised a bibliographic state of art providing a contemporary clinical and preclinical studies dealing with nutritional factors in sport-related concussion. RESULTS Numerous supplements, including n-3 polyunsaturated fatty acids, sulfur amino acids, antioxidants and minerals, have shown promising results as aids to concussion recovery or prevention in animal studies, most of which use a fluid percussion technique to cause brain injury, and in a few human studies of severe or moderate traumatic brain injury. Current ongoing human trials can hopefully provide us with more information, in particular, on new options, i.e. probiotics, lactate or amino acids, for the use of nutritional supplements for concussed athletes. CONCLUSION Nutritional supplementation has emerged as a potential strategy to prevent and/or reduce the deleterious effects of sports-related concussion and subconcussive impacts.
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Affiliation(s)
- S Walrand
- Service de Nutrition Clinique, CHU Clermont-Ferrand, Université Clermont-Auvergne, 63000 Clermont-Ferrand, France.
| | - R Gaulmin
- Service médical, ASM Clermont-Auvergne Rugby, 63028 Clermont-Ferrand cedex 2, France
| | - R Aubin
- Service médical, ASM Clermont-Auvergne Rugby, 63028 Clermont-Ferrand cedex 2, France
| | - V Sapin
- Service de Biochimie & Génétique Moléculaire, CHU Clermont-Ferrand, Université Clermont Auvergne, 63000 Clermont-Ferrand, France
| | - A Coste
- Service de Neurochirurgie, CHU Clermont-Ferrand, 63000 Clermont-Ferrand, France
| | - M Abbot
- Service médical, ASM Clermont-Auvergne Rugby, 63028 Clermont-Ferrand cedex 2, France; Service de Médecine du Sport, CHU Clermont-Ferrand, 63000 Clermont-Ferrand, France
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4
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Zielinski MR, Systrom DM, Rose NR. Fatigue, Sleep, and Autoimmune and Related Disorders. Front Immunol 2019; 10:1827. [PMID: 31447842 PMCID: PMC6691096 DOI: 10.3389/fimmu.2019.01827] [Citation(s) in RCA: 111] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 07/18/2019] [Indexed: 12/13/2022] Open
Abstract
Profound and debilitating fatigue is the most common complaint reported among individuals with autoimmune disease, such as systemic lupus erythematosus, multiple sclerosis, type 1 diabetes, celiac disease, chronic fatigue syndrome, and rheumatoid arthritis. Fatigue is multi-faceted and broadly defined, which makes understanding the cause of its manifestations especially difficult in conditions with diverse pathology including autoimmune diseases. In general, fatigue is defined by debilitating periods of exhaustion that interfere with normal activities. The severity and duration of fatigue episodes vary, but fatigue can cause difficulty for even simple tasks like climbing stairs or crossing the room. The exact mechanisms of fatigue are not well-understood, perhaps due to its broad definition. Nevertheless, physiological processes known to play a role in fatigue include oxygen/nutrient supply, metabolism, mood, motivation, and sleepiness-all which are affected by inflammation. Additionally, an important contributing element to fatigue is the central nervous system-a region impacted either directly or indirectly in numerous autoimmune and related disorders. This review describes how inflammation and the central nervous system contribute to fatigue and suggests potential mechanisms involved in fatigue that are likely exhibited in autoimmune and related diseases.
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Affiliation(s)
- Mark R Zielinski
- Veterans Affairs Boston Healthcare System, Boston, MA, United States.,Department of Psychiatry, Harvard Medical School, Boston, MA, United States
| | - David M Systrom
- Department of Medicine, Harvard Medical School, Boston, MA, United States.,Department of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, Boston, MA, United States
| | - Noel R Rose
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States
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Rohde J, Pedersen HR, Bjerring PN, Larsen FS. Effects of dexamethasone and cox inhibitors on intracranial pressure and cerebral perfusion in the lipopolysaccharide treated rats with hyperammonemia. PLoS One 2015; 10:e0117416. [PMID: 25675251 PMCID: PMC4326460 DOI: 10.1371/journal.pone.0117416] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Accepted: 12/22/2014] [Indexed: 12/30/2022] Open
Abstract
Introduction Systemic inflammation may affect the brain by aggravating the stage of encephalopathy and increasing intracranial pressure (ICP) especially if liver insufficiency with hyperammonemia is present. The aim of this study was to determine if the influence of concomitant hyperammonemia and lipopolysaccharide (LPS) on the brain can be prevented by dexamethasone and cyclooxygenase (COX) inhibitors. Method Fifty-four male Wistar rats, 6 in each group, were divided into the following groups: Saline+saline; LPS (2mg/kg)+saline; LPS+indomethacin (10mg/kg); LPS+diclofenac (10mg/kg); LPS+dexamethasone (2mg/kg) in experiment A. Experiment-B included the following groups: LPS+NH3 (140μmol/kg/min)+saline; LPS+NH3+indomethacin; LPS+NH3+diclofenac and LPS+NH3+dexamethasone. ICP was monitored via a catheter placed in cisterna magna and changes in CBF were recorded by laser Doppler flowmetry. Results LPS with and without NH3 induced a similar increase in plasma 6-keto-prostaglandin-F1α (6-keto-PGF1α) concentration together with a concomitant rise in CBF and ICP. Indomethacin and diclofenac prevented the increase in ICP by LPS alone, and with the addition of NH3 the increase in both CBF and ICP, which was associated with a decrease in 6-keto-PGF1α. Dexamethasone only reduced the LPS induced increase in ICP but not CBF, and partly the 6-keto-PGF1α plasma concentration in the combined setup. Conclusion These data indicate that activation of cycloooxygenases is of central importance for development of cerebral hyperemia and high ICP during concomitant systemic inflammation and hyperammonemia.
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Affiliation(s)
- Johan Rohde
- Department of Hepatology, A-2121 Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100, Copenhagen, Denmark
- * E-mail:
| | - Hans R. Pedersen
- Department of Hepatology, A-2121 Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100, Copenhagen, Denmark
| | - Peter N. Bjerring
- Department of Hepatology, A-2121 Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100, Copenhagen, Denmark
| | - Fin Stolze Larsen
- Department of Hepatology, A-2121 Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100, Copenhagen, Denmark
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Exposure to inflammatory cytokines IL-1β and TNFα induces compromise and death of astrocytes; implications for chronic neuroinflammation. PLoS One 2013; 8:e84269. [PMID: 24367648 PMCID: PMC3868583 DOI: 10.1371/journal.pone.0084269] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 11/21/2013] [Indexed: 02/06/2023] Open
Abstract
Background Astrocytes have critical roles in the human CNS in health and disease. They provide trophic support to neurons and are innate-immune cells with keys roles during states-of-inflammation. In addition, they have integral functions associated with maintaining the integrity of the blood-brain barrier. Methods We have used cytometric bead arrays and xCELLigence technology to monitor the to monitor the inflammatory response profiles and astrocyte compromise in real-time under various inflammatory conditions. Responses were compared to a variety of inflammatory cytokines known to be released in the CNS during neuroinflammation. Astrocyte compromise measured by xCELLigence was confirmed using ATP measurements, cleaved caspase 3 expression, assessment of nuclear morphology and cell death. Results Inflammatory activation (IL-1β or TNFα) of astrocytes results in the transient production of key inflammatory mediators including IL-6, cell surface adhesion molecules, and various leukocyte chemoattractants. Following this phase, the NT2-astrocytes progressively become compromised, which is indicated by a loss of adhesion, appearance of apoptotic nuclei and reduction in ATP levels, followed by DEATH. The earliest signs of astrocyte compromise were observed between 24-48h post cytokine treatment. However, significant cell loss was not observed until at least 72h, where there was also an increase in the expression of cleaved-caspase 3. By 96 hours approximately 50% of the astrocytes were dead, with many of the remaining showing signs of compromise too. Numerous other inflammatory factors were tested, however these effects were only observed with IL-1β or TNFα treatment. Conclusions Here we reveal direct sensitivity to mediators of the inflammatory milieu. We highlight the power of xCELLigence technology for revealing the early progressive compromise of the astrocytes, which occurs 24-48 hours prior to substantive cell loss. Death induced by IL-1β or TNFα is relevant clinically as these two cytokines are produced by various peripheral tissues and by resident brain cells.
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Radak Z, Ihasz F, Koltai E, Goto S, Taylor AW, Boldogh I. The redox-associated adaptive response of brain to physical exercise. Free Radic Res 2013; 48:84-92. [PMID: 23870001 DOI: 10.3109/10715762.2013.826352] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Reactive oxygen species (ROS) are continuously generated during metabolism. ROS are involved in redox signaling, but in significant concentrations they can greatly elevate oxidative damage leading to neurodegeneration. Because of the enhanced sensitivity of brain to ROS, it is especially important to maintain a normal redox state in brain and spinal cord cell types. The complex effects of exercise benefit brain function, including functional enhancement as well as its preventive and therapeutic roles. Exercise can induce neurogenesis via neurotrophic factors, increase capillarization, decrease oxidative damage, and enhance repair of oxidative damage. Exercise is also effective in attenuating age-associated loss in brain function, which suggests that physical activity-related complex metabolic and redox changes are important for a healthy neural system.
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Affiliation(s)
- Z Radak
- Faculty of Physical Education and Sport Sciences, Institute of Sport Science, Semmelweis University , Budapest , Hungary
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Shad KF, Aghazadeh Y, Ahmad S, Kress B. Peripheral markers of Alzheimer's disease: Surveillance of white blood cells. Synapse 2013; 67:541-3. [DOI: 10.1002/syn.21651] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Accepted: 02/07/2013] [Indexed: 11/07/2022]
Affiliation(s)
- Kaneez Fatima Shad
- PAP RSB Institute of Health Sciences; Universiti Brunei Darussalam; Jalan Tungku Link; Gadong; BE 1410; Brunei Darussalam
| | - Yashar Aghazadeh
- Chefarzt des Instituts für Neuroradiologie; Krankenhaus Nordwest; Steinbacher Hohl 2-26; 60488; Frankfurt; Germany
| | - Sagheer Ahmad
- PAP RSB Institute of Health Sciences; Universiti Brunei Darussalam; Jalan Tungku Link; Gadong; BE 1410; Brunei Darussalam
| | - Bodo Kress
- Chefarzt des Instituts für Neuroradiologie; Krankenhaus Nordwest; Steinbacher Hohl 2-26; 60488; Frankfurt; Germany
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Calderón-Garcidueñas L, Engle R, Mora-Tiscareño A, Styner M, Gómez-Garza G, Zhu H, Jewells V, Torres-Jardón R, Romero L, Monroy-Acosta ME, Bryant C, González-González LO, Medina-Cortina H, D'Angiulli A. Exposure to severe urban air pollution influences cognitive outcomes, brain volume and systemic inflammation in clinically healthy children. Brain Cogn 2011; 77:345-55. [PMID: 22032805 DOI: 10.1016/j.bandc.2011.09.006] [Citation(s) in RCA: 199] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2011] [Revised: 09/22/2011] [Accepted: 09/26/2011] [Indexed: 12/31/2022]
Abstract
Exposure to severe air pollution produces neuroinflammation and structural brain alterations in children. We tested whether patterns of brain growth, cognitive deficits and white matter hyperintensities (WMH) are associated with exposures to severe air pollution. Baseline and 1 year follow-up measurements of global and regional brain MRI volumes, cognitive abilities (Wechsler Intelligence Scale for Children-Revised, WISC-R), and serum inflammatory mediators were collected in 20 Mexico City (MC) children (10 with white matter hyperintensities, WMH(+), and 10 without, WMH(-)) and 10 matched controls (CTL) from a low polluted city. There were significant differences in white matter volumes between CTL and MC children - both WMH(+) and WMH(-) - in right parietal and bilateral temporal areas. Both WMH(-) and WMH(+) MC children showed progressive deficits, compared to CTL children, on the WISC-R Vocabulary and Digit Span subtests. The cognitive deficits in highly exposed children match the localization of the volumetric differences detected over the 1 year follow-up, since the deficits observed are consistent with impairment of parietal and temporal lobe functions. Regardless of the presence of prefrontal WMH, Mexico City children performed more poorly across a variety of cognitive tests, compared to CTL children, thus WMH(+) is likely only partially identifying underlying white matter pathology. Together these findings reveal that exposure to air pollution may perturb the trajectory of cerebral development and result in cognitive deficits during childhood.
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10
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Age-associated neurodegeneration and oxidative damage to lipids, proteins and DNA. Mol Aspects Med 2011; 32:305-15. [DOI: 10.1016/j.mam.2011.10.010] [Citation(s) in RCA: 157] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Accepted: 10/11/2011] [Indexed: 01/08/2023]
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Strazza M, Pirrone V, Wigdahl B, Nonnemacher MR. Breaking down the barrier: the effects of HIV-1 on the blood-brain barrier. Brain Res 2011; 1399:96-115. [PMID: 21641584 DOI: 10.1016/j.brainres.2011.05.015] [Citation(s) in RCA: 150] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2010] [Revised: 05/06/2011] [Accepted: 05/07/2011] [Indexed: 01/13/2023]
Abstract
Human immunodeficiency virus type 1 (HIV-1) primarily infects CD4(+) T cells and cells of the monocyte-macrophage lineage, resulting in immunodeficiency in an infected patient. Along with this immune deficiency, HIV-1 has been linked to a number of neurological symptoms in the absence of opportunistic infections or other co-morbidities, suggesting that HIV-1 is able to cross the blood-brain barrier (BBB), enter the central nervous system (CNS), and cause neurocognitive impairment. HIV-1-infected monocyte-macrophages traverse the BBB and enter the CNS throughout the course of HIV-1 disease. Once in the brain, both free virus and virus-infected cells are able to infect neighboring resident microglia and astrocytes and possibly other cell types. HIV-1-infected cells in both the periphery and the CNS give rise to elevated levels of viral proteins, including gp120, Tat, and Nef, and of host inflammatory mediators such as cytokines and chemokines. It has been shown that the viral proteins may act alone or in concert with host cytokines and chemokines, affecting the integrity of the BBB. The pathological end point of these interactions may facilitate a positive feedback loop resulting in increased penetration of HIV into the CNS. It is proposed in this review that the dysregulation of the BBB during and after neuroinvasion is a critical component of the neuropathogenic process and that dysregulation of this protective barrier is caused by a combination of viral and host factors including secreted viral proteins, components of the inflammatory process, the aging process, therapeutics, and drug or alcohol abuse.
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Affiliation(s)
- Marianne Strazza
- Department of Microbiology and Immunology, and Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA 19102, USA
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Zhang WJ, Feng J, Zhou R, Ye LY, Liu HL, Peng L, Lou JN, Li CH. Tanshinone IIA protects the human blood-brain barrier model from leukocyte-associated hypoxia-reoxygenation injury. Eur J Pharmacol 2010; 648:146-52. [PMID: 20826144 DOI: 10.1016/j.ejphar.2010.08.040] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Revised: 07/21/2010] [Accepted: 08/25/2010] [Indexed: 12/11/2022]
Abstract
To investigate the in vitro effect of tanshinone IIA on leukocyte-associated hypoxia-reoxygenation injury of human brain-blood barrier (BBB), we established the BBB model by culturing purified primary human brain microvascular endothelial cells (HBMVEC) to confluence on cell culture insert. BBB was identified by tight junction, transendothelial electrical resistance (TEER) and the permeability of BBB to horseradish peroxidase (HRP). The effect of tanshinone IIA on the permeability of BBB was tested at 2 h after hypoxia and 1h after reoxygenation with or without the supernatants of activated leukocytes. The effect of tanshinone IIA on leukocytes activation was analyzed by detection of MMP-9, cytokines and reactive oxygen species. The results showed that BBB formed by confluent HBMVECs had no cellular gap. Immunofluorescent staining for ZO-1 confirmed that the cells were connected by tight junction. Moreover, the BBB model had a higher TEER and a lower permeability for HRP than confluent HUVECs. The permeability of BBB for HRP was enhanced by hypoxia-reoxygenation and further greatly enhanced by adding the supernatants of activated leukocytes before reoxygenation. But such an effect was reversed by addition of tanshinone IIA before hypoxia. Moreover, tanshinone IIA could decrease the levels of MMP-9, TNF-α, IL-1α, IL-2, IFN-γ and reactive oxygen species in leukocytes. In conclusion, tanshinone IIA can protect BBB against leukocyte-associated hypoxia-reoxygenation injury by attenuating the activation of leukocytes and inhibiting the injury effects of leukocytic products. Tanshinone IIA may be a novel therapeutic agent for cerebral ischemia-reperfusion injury.
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Affiliation(s)
- Wen-jian Zhang
- Institute of Clinical Medical Sciences, China-Japan Friendship Hospital, Beijing 100029, PR China
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Toda N, Ayajiki K, Okamura T. Cerebral blood flow regulation by nitric oxide in neurological disorders. Can J Physiol Pharmacol 2010; 87:581-94. [PMID: 19767882 DOI: 10.1139/y09-048] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
There has been a rapid increase in the amount of information on the physiological and pathophysiological roles of nitric oxide (NO) in the brain. This molecule, which is formed by the constitutive isoforms of NO synthase, endothelial (eNOS) and neuronal (nNOS), plays an obligatory role in the regulation of cerebral blood flow and cell viability and in the protection of nerve cells or fibres against pathogenic factors associated with Alzheimer's disease, Huntington's disease, seizures, and migraine. Cerebral blood flow is impaired by decreased formation of NO from endothelial cells, autonomic nitrergic nerves, or brain neurons and also by increased production of reactive oxygen species (ROS). The NO-ROS interaction is an important topic in discussing blood flow and cell viability in the brain. Excessive production of NO by inducible NOS (iNOS) and nNOS in the brain participates in neurotoxicity. Recent studies on brain circulation have provided useful information about the involvement of impaired NO availability or uncontrolled NO production in cerebral pathogenesis, including Alzheimer's disease, seizures, vascular headaches, and inflammatory disorders. Insight into the role of NO in the brain will contribute to our better understanding of cerebral hemodynamic dysfunction and will aid in developing novel therapeutic measures in diseases of the central nervous system.
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Affiliation(s)
- Noboru Toda
- Toyama Institute for Cardiovascular Pharmacology Research, 7-13, 1-Chome, Azuchi-machi, Chuo-ku, Osaka 541-0052, Japan.
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Uranova NA, Zimina IS, Vikhreva OV, Krukov NO, Rachmanova VI, Orlovskaya DD. Ultrastructural damage of capillaries in the neocortex in schizophrenia. World J Biol Psychiatry 2010; 11:567-78. [PMID: 20109113 DOI: 10.3109/15622970903414188] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVES Neuroimaging studies showed lowered blood flow, glucose metabolic rates and hypoactivation of the prefrontal cortex (PFC) in patients with schizophrenia. The aim of the study was to clear up whether there are abnormalities in the microvasculature in the neocortex in schizophrenia. METHODS Capillaries were studied in PFC (BA 10) and visual cortex (VC) (BA 17) by electron microscopy and morphometry in 26 schizophrenia cases and 26 normal controls. Capillary diameter and areas of capillaries and of pericapillary astrocytic end-feet were estimated in layers I-II of the prefrontal and visual cortices. RESULTS Ultrastructural abnormalities of capillaries in schizophrenia included thickening, deformation of basal lamina, vacuolation of cytoplasm of endothelial cells, basal lamina and astrocytic end-feet, swelling of astrocytic end-feet, of pericapillary oligodendrocytes and signs of activation of microglial cells in both PFC and VC. Capillary diameter and area did not differ significantly between the groups. Area of astrocytic end-feet was significantly higher in PFC (+49%, P<0.001) and in VC (+29%, P<0.01) in schizophrenic group and in different clinical subgroups as compared to controls. CONCLUSIONS Ultrastructural abnormalities of capillaries and of pericapillary cellular environment found suggest that blood-brain barrier dysfunction might contribute to the pathogenesis of cortical lesions in schizophrenia.
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Affiliation(s)
- Natalya A Uranova
- Laboratory of Clinical Neuropathology, Mental Health Research Center, Russian Academy of Medical Sciences, Zagorodnoe shosse 2, Moscow, Russia.
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Xie H, Xue YX, Liu LB, Liu YH. Endothelial-monocyte-activating polypeptide II increases blood-tumor barrier permeability by down-regulating the expression levels of tight junction associated proteins. Brain Res 2010; 1319:13-20. [PMID: 20083091 DOI: 10.1016/j.brainres.2010.01.023] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2009] [Revised: 01/06/2010] [Accepted: 01/11/2010] [Indexed: 11/17/2022]
Abstract
This study was performed to determine whether endothelial-monocyte-activating polypeptide (EMAP) II increases the permeability of the blood-tumor barrier (BTB) in the rat model of C6 glioma, and whether EMAP II opens the BTB by affecting tight junction (TJ) associated proteins zonula occluden-1 (ZO-1), occludin and claudin-5. The rats were divided into eight groups randomly: control group, EMAPII 0h group, EMAPII 0.5h group, EMAPII 1h group, EMAPII 2h group, EMAPII 3h group, EMAPII 6h group and EMAPII 12h group. The BTB permeability was assessed by Evans blue extravasation. The mRNA and protein expressions of ZO-1, occludin, and claudin-5 were determined by reverse transcriptase-polymerase chain reaction, western blot, and immunohistochemistry assays. The BTB permeability significantly increased after EMAP II injection in different doses (40ng/kg, 80ng/kg and 160ng/kg). The BTB permeability started to increase from 0.5h, reached a peak at 1h, and finally returned to the level of EMAP II 0h group after EMAP II injection at dose of 80ng/kg. The mRNA and protein expression levels of ZO-1, occludin and claudin-5 were significantly decreased after EMAP II injection. This study demonstrates for the first time that EMAP II increases the permeability of BTB selectively, and the possible mechanism is associated with the down-regulation of ZO-1, occludin and claudin-5.
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Affiliation(s)
- Hui Xie
- Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang, Liaoning province, 110001, PR China
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Capillary injury in the ischemic brain of hyperlipidemic, apolipoprotein B-100 transgenic mice. Life Sci 2009; 84:935-9. [PMID: 19409916 DOI: 10.1016/j.lfs.2009.04.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2009] [Revised: 03/26/2009] [Accepted: 04/17/2009] [Indexed: 01/07/2023]
Abstract
AIMS Apolipoprotein B-100 (apoB-100) has been implicated in hyperlipidemia, which contributes to the pathogenesis of vascular disorders. Our aim was to investigate whether the expression of human apoB-100 in transgenic mice and/or a high-cholesterol diet cause cerebral microvascular lesions, and whether these conditions augment ischemia-related capillary damage. MAIN METHODS Human apoB-100 overexpressing transgenic (Tg(apoB-100), n=23) and wild-type mice (C5/B6, Wt, n=26) were supplied with standard or 2% cholesterol-enriched diet for 17-19 weeks. Cerebral ischemia was induced by unilateral common carotid artery occlusion. Cortical samples were embedded for electron microscopy. Microvascular density (number of microvascular profiles/examined area), lumen diameter, the swelling of astrocytic endfeet, the occurrence of endothelial microvilli (affected capillaries expressed as ratio of all capillaries encountered), and the ratio of intact capillaries (devoid of all the above pathology) were calculated. KEY FINDINGS The expression of apoB-100 coincided with decreased cortical microvascular density (195+/-7 vs. 223+/-8 vessels/mm(2), vs. Wt; P<0.008) and increased capillary lumen diameter (3.16+/-0.5 vs. 2.88+/-0.6 microm, vs. Wt; P<0.001). Cerebral ischemia promoted the swelling of perivascular astrocytes (62.1+/-4.2 vs. 36.5+/-4.0%, vs. contralateral, Wt; P<0.001), and reduced the ratio of intact capillaries (32.1+/-5.6 vs. 65.2+/-3.7%, vs. contralateral, Wt; P<0.001). Hyperlipidemia did not exacerbate the injury. SIGNIFICANCE The overexpression of human apoB-100 alters the density of the microvascular network and the diameter of capillaries, which may compromise cerebrovascular reactivity during ischemia.
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Abstract
Patients with acute liver failure (ALF) display impairment of cerebral blood flow (CBF) autoregulation, which may contribute to the development of fatal intracranial hypertension, but the pathophysiological mechanism remains unclear. In this study, we examined whether loss of liver mass causes impairment of CBF autoregulation. Four rat models were chosen, each representing different aspects of ALF: galactosamine (GlN) intoxication represented liver necrosis, 90% hepatectomy (PHx90) represented reduction in liver mass, portacaval anastomosis (PCA) represented shunting of blood/toxins into the systemic circulation thus mimicking intrahepatic shunting in ALF, PCA+NH(3) provided information about the additional effects of hyperammonemia Rats were intubated and sedated with pentobarbital. We measured CBF with laser Doppler, intracranial pressure (ICP) was measured in the fossa posterior and registered with a pressure transducer, brain water was measured using the wet-to-dry method, and cerebral glutamine/glutamate was measured enzymatically. The CBF autoregulatory index in both the GlN and PHx90 groups differed significantly from the control group. Conversely, CBF autoregulation was intact in the PCA and PCA+NH(3) groups despite high arterial ammonia, high cerebral glutamine concentration, and increased CBF and ICP. Increased water content of the brainstem or cerebellum was not associated with defective CBF autoregulation. In conclusion, impairment of CBF autoregulation is not caused by brain edema/high ICP. Nor does portacaval shunting or hyperammonemia impair autoregulation. Rather, massive liver necrosis and reduced liver mass are associated with loss of CBF autoregulation.
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Calderón-Garcidueñas L, Solt AC, Henríquez-Roldán C, Torres-Jardón R, Nuse B, Herritt L, Villarreal-Calderón R, Osnaya N, Stone I, García R, Brooks DM, González-Maciel A, Reynoso-Robles R, Delgado-Chávez R, Reed W. Long-term air pollution exposure is associated with neuroinflammation, an altered innate immune response, disruption of the blood-brain barrier, ultrafine particulate deposition, and accumulation of amyloid beta-42 and alpha-synuclein in children and young adults. Toxicol Pathol 2008; 36:289-310. [PMID: 18349428 DOI: 10.1177/0192623307313011] [Citation(s) in RCA: 619] [Impact Index Per Article: 38.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Air pollution is a serious environmental problem. We investigated whether residency in cities with high air pollution is associated with neuroinflammation/neurodegeneration in healthy children and young adults who died suddenly. We measured mRNA cyclooxygenase-2, interleukin-1beta, and CD14 in target brain regions from low (n = 12) or highly exposed residents (n = 35) aged 25.1 +/- 1.5 years. Upregulation of cyclooxygenase-2, interleukin-1beta, and CD14 in olfactory bulb, frontal cortex, substantia nigrae and vagus nerves; disruption of the blood-brain barrier; endothelial activation, oxidative stress, and inflammatory cell trafficking were seen in highly exposed subjects. Amyloid beta42 (Abeta42) immunoreactivity was observed in 58.8% of apolipoprotein E (APOE) 3/3 < 25 y, and 100% of the APOE 4 subjects, whereas alpha-synuclein was seen in 23.5% of < 25 y subjects. Particulate material (PM) was seen in olfactory bulb neurons, and PM < 100 nm were observed in intraluminal erythrocytes from lung, frontal, and trigeminal ganglia capillaries. Exposure to air pollution causes neuroinflammation, an altered brain innate immune response, and accumulation of Abeta42 and alpha-synuclein starting in childhood. Exposure to air pollution should be considered a risk factor for Alzheimer's and Parkinson's diseases, and carriers of the APOE 4 allele could have a higher risk of developing Alzheimer's disease if they reside in a polluted environment.
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Pedersen HR, Ring-Larsen H, Olsen NV, Larsen FS. Hyperammonemia acts synergistically with lipopolysaccharide in inducing changes in cerebral hemodynamics in rats anaesthetised with pentobarbital. J Hepatol 2007; 47:245-52. [PMID: 17532089 DOI: 10.1016/j.jhep.2007.03.026] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2006] [Revised: 03/12/2007] [Accepted: 03/27/2007] [Indexed: 01/16/2023]
Abstract
BACKGROUND/AIMS The aim was to determine the effect of ammonia (NH(3)) and lipopolysaccharide (LPS) alone or in combination, on cerebral blood flow (CBF) and intracranial pressure (ICP) in the rat. Since amiloride-sensitive-ion-pathways in the blood-brain barrier (BBB) modulate CBF, we also aimed to test if Na(+)/H(+)-inhibitors could prevent this possible synergism between NH(3) and LPS. METHODS In experiment A, four groups of rats received ammonium acetate (140 micromol/kg/min) or saline, each of them associated with either vehicle or LPS (2 mg/kg). In experiments B and C, rats received similar treatments after having received amiloride (30 mg/kg) or 5-(N-methyl-N-isobutyl)-amiloride (MIA, 5 mg/kg). Plasma tumor-necrosis-factor-alpha (TNF-alpha), ICP (via a cisterna magna catheter) and CBF (by laser-Doppler flowmetry) were measured. RESULTS An increase in ICP and CBF within 60 min was observed only in rats that received NH(3) together with LPS as compared to any other group (P<0.01), which could be prevented by amiloride (P<0.05), but not by MIA. Both amiloride and MIA decreased the plasma TNF-alpha concentration. CONCLUSIONS In rats anaesthetised with pentobarbital NH(3) infusion aggravates a LPS induced rise in ICP and induces an increase in CBF less clearly seen with LPS alone. This effect is prevented by the non-specific Na(+)/H(+) inhibitor amiloride, but not by MIA, a specific inhibitor of Na(+)/H(+) exchanger. Thus, the synergistic effect of NH(3) and LPS seems mediated by other amiloride-sensitive-ion-pathways in the BBB than the Na(+)/H(+) exchanger.
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Affiliation(s)
- Hans R Pedersen
- Department of Hepatology, Rigshospitalet, Section A-2121, Copenhagen University Hospital, Blegdamsvej 9, 2100 Copenhagen, Denmark
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Zhao C, Ling Z, Newman MB, Bhatia A, Carvey PM. TNF-alpha knockout and minocycline treatment attenuates blood-brain barrier leakage in MPTP-treated mice. Neurobiol Dis 2007; 26:36-46. [PMID: 17234424 PMCID: PMC1892817 DOI: 10.1016/j.nbd.2006.11.012] [Citation(s) in RCA: 129] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2006] [Revised: 11/14/2006] [Accepted: 11/22/2006] [Indexed: 11/19/2022] Open
Abstract
Following intraparenchymal injection of the dopamine (DA) neurotoxin 6-hydroxydopamine, we previously demonstrated passage of fluoresceinisothiocyanate-labeled albumin (FITC-LA) from blood into the substantia nigra (SN) and striatum suggesting damage to the blood-brain barrier (BBB). The factors contributing to the BBB leakage could have included neuroinflammation, loss of DA neuron control of barrier function, or a combination of both. In order to determine which factor(s) was responsible, we assessed BBB integrity using the FITC-LA technique in wild-type (WT), tumor necrosis factor alpha (TNF-alpha) knockout (KO), and minocycline (an inhibitor of microglia activation) treated mice 72 h following treatment with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Compared with WT mice, TNF-alpha KO mice treated with MPTP showed reduced FITC-LA leakage, decreased numbers of activated microglia, and reduced proinflammatory cytokines (TNF-alpha and interleukin 1beta) associated with significant MPTP-induced DA neuron loss. In contrast, minocycline treated animals did not exhibit significant MPTP-induced DA neuron loss although their FITC-LA leakage, numbers of activated microglia, and MPTP-induced cytokines were markedly attenuated. Since both TNF-alpha KO and minocycline treatment attenuated MPTP-induced BBB dysfunction, microglial activation, and cytokine increases, but had differential effects on DA neuron loss, it appears that neuroinflammation and not DA neuron loss was responsible for disrupting the blood-brain barrier integrity.
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Affiliation(s)
- Chaohui Zhao
- Department of Pharmacology, Rush University Medical Center, Chicago IL USA
| | - Zaodung Ling
- Department of Pharmacology, Rush University Medical Center, Chicago IL USA
| | - Mary B. Newman
- Department of Pharmacology, Rush University Medical Center, Chicago IL USA
- Department of Neuroscience, Rush University Medical Center, Chicago IL USA
| | - Ankush Bhatia
- Department of Pharmacology, Rush University Medical Center, Chicago IL USA
| | - Paul M. Carvey
- Department of Pharmacology, Rush University Medical Center, Chicago IL USA
- Department of Neuroscience, Rush University Medical Center, Chicago IL USA
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