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Abstract
Neuronal survival, electrical signaling and synaptic activity require a well-balanced micro-environment in the central nervous system. This is achieved by the blood-brain barrier (BBB), an endothelial barrier situated in the brain capillaries, that controls near-to-all passage in and out of the brain. The endothelial barrier function is highly dependent on signaling interactions with surrounding glial, neuronal and vascular cells, together forming the neuro-glio-vascular unit. Within this functional unit, connexin (Cx) channels are of utmost importance for intercellular communication between the different cellular compartments. Connexins are best known as the building blocks of gap junction (GJ) channels that enable direct cell-cell transfer of metabolic, biochemical and electric signals. In addition, beyond their role in direct intercellular communication, Cxs also form unapposed, non-junctional hemichannels in the plasma membrane that allow the passage of several paracrine messengers, complementing direct GJ communication. Within the NGVU, Cxs are expressed in vascular endothelial cells, including those that form the BBB, and are eminent in astrocytes, especially at their endfoot processes that wrap around cerebral vessels. However, despite the density of Cx channels at this so-called gliovascular interface, it remains unclear as to how Cx-based signaling between astrocytes and BBB endothelial cells may converge control over BBB permeability in health and disease. In this review we describe available evidence that supports a role for astroglial as well as endothelial Cxs in the regulation of BBB permeability during development as well as in disease states.
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FTY720 Attenuates Infection-Induced Enhancement of Aβ Accumulation in APP/PS1 Mice by Modulating Astrocytic Activation. J Neuroimmune Pharmacol 2017. [PMID: 28620801 DOI: 10.1007/s11481-017-9753-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
It is well established that infection has a significant detrimental effect on patients with Alzheimer's disease (AD), accelerating cognitive decline and, even in healthy ageing individuals, increasing amyloid-β (Aβ) accumulation in the brain. In animal models of AD infection can also cause damage, with evidence of increased neuroinflammation, amyloid pathology and deterioration of cognitive function. These changes are against a backdrop of an age- and AD-related increase in susceptibility to infection. Here we set out to determine whether FTY720, a molecule that binds sphingosine-1-phosphate (S1P) receptors and with known immunosuppressant effects mediating its therapeutic action in multiple sclerosis (MS), might modulate the impact of infection in a mouse model of AD. Transgenic mice that overexpress amyloid precursor protein (APP) and presenilin 1 (PS1; APP/PS1 mice) and their littermates were/were not infected with Bordetella pertussis and were treated orally with FTY720 or vehicle beginning 3 days before infection. Infection increased astrocytic activation and enhanced blood brain barrier (BBB) permeability and these changes were attenuated in FTY720-treated B. pertussis-infected mice. Significantly, infection increased Aβ containing plaques and soluble Aβ and these infection-related changes were also attenuated in FTY720-treated B. pertussis-infected mice. The data suggest that this effect results from an FTY720-induced increase in Aβ phagocytosis by astrocytes. FTY720 did not impact on genotype-related changes in the absence of an infection indicating that its potential usefulness is restricted to reducing the impact of acute inflammatory stimuli in AD.
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303
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Bogush M, Heldt NA, Persidsky Y. Blood Brain Barrier Injury in Diabetes: Unrecognized Effects on Brain and Cognition. J Neuroimmune Pharmacol 2017; 12:593-601. [PMID: 28555373 DOI: 10.1007/s11481-017-9752-7] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2017] [Accepted: 05/19/2017] [Indexed: 12/16/2022]
Abstract
Diabetes mellitus (DM) is a disorder due to the inability properly to metabolize glucose associated with dysregulation of metabolic pathways of lipids and proteins resulting in structural and functional changes of various organ systems. DM has detrimental effects on the vasculature, resulting in the development of various cardiovascular diseases and stemming from microvascular injury. The blood brain barrier (BBB) is a highly specialized structure protecting the unique microenvironment of the brain. Endothelial cells, connected by junctional complexes and expressing numerous transporters, constitute the main cell type in the BBB. Other components, including pericytes, basement membrane, astrocytes and perivascular macrophages, join endothelial cells to form the neurovascular unit (NVU) and contribute to the proper function and integrity of the BBB. The role of the BBB in the pathogenesis of diabetic encephalopathy and other diabetes-related complications in the central nervous system is apparent. However, the mechanisms, timing and consequences of BBB injury in diabetes are not well understood. The importance of further studies related to barrier dysfunction in diabetes is dictated by its potential involvement in the cognitive demise associated with DM. This review summarizes the impact of DM on BBB/NVU integrity and function leading to neurological and cognitive complications.
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Affiliation(s)
- Marina Bogush
- Department of Pathology and Laboratory Medicine, Temple University Lewis Katz School of Medicine, Philadelphia, PA, 19140, USA
| | - Nathan A Heldt
- Department of Pathology and Laboratory Medicine, Temple University Lewis Katz School of Medicine, Philadelphia, PA, 19140, USA
| | - Yuri Persidsky
- Department of Pathology and Laboratory Medicine, Temple University Lewis Katz School of Medicine, Philadelphia, PA, 19140, USA. .,Center for Substance Abuse Research, Temple University Lewis Katz School of Medicine, Philadelphia, PA, 19140, USA.
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304
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Koyama Y, Ukita A, Abe K, Iwamae K, Tokuyama S, Tanaka K, Kotake Y. Dexamethasone Downregulates Endothelin Receptors and Reduces Endothelin-Induced Production of Matrix Metalloproteinases in Cultured Rat Astrocytes. Mol Pharmacol 2017; 92:57-66. [PMID: 28461586 DOI: 10.1124/mol.116.107300] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Accepted: 04/25/2017] [Indexed: 12/31/2022] Open
Abstract
In brain disorders, astrocytes change phenotype to reactive astrocytes and are involved in the induction of neuroinflammation and brain edema. The administration of glucocorticoids (GCs), such as dexamethasone (Dex), reduces astrocytic activation, but the mechanisms underlying this inhibitory action are not well understood. Endothelins (ETs) promote astrocytic activation. Therefore, the effects of Dex on ET receptor expressions were examined in cultured rat astrocytes. Treatment with 300 nM Dex for 6-48 hours reduced the mRNA expression of astrocytic ETA and ETB receptors to 30-40% of nontreated cells. Levels of ETA and ETB receptor proteins became about 50% of nontreated cells after Dex treatment. Astrocytic ETA and ETB receptor mRNAs were decreased by 300 nM hydrocortisone. The effects of Dex and hydrocortisone on astrocytic ET receptors were abolished in the presence of mifepristone, a GC receptor antagonist. Although Dex did not decrease the basal levels of matrix metalloproteinase (MMP) 3 and MMP9 mRNAs, pretreatment with Dex reduced ET-induced increases in MMP mRNAs. The effects of ET-1 on the release of MMP3 and MMP9 proteins were attenuated by pretreatment with Dex. ET-1 stimulated the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) in cultured astrocytes. Pretreatment with Dex reduced the ET-induced increases in ERK1/2 phosphorylation. In contrast, pretreatment with Dex did not affect MMP production or ERK1/2 phosphorylation induced by phorbol myristate acetate, a protein kinase C activator. These results indicate that Dex downregulates astrocytic ET receptors and reduces ET-induced MMP production.
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Affiliation(s)
- Yutaka Koyama
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tonda-bayashi, Osaka, Japan (Y.Koy., A.U., K.A., K.I., K.T., Y.Kot.); and Department of Clinical Pharmacy, School of Pharmaceutical Sciences, Kobe Gakuin University, Minatojima, Kobe, Japan (S.T.)
| | - Ayano Ukita
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tonda-bayashi, Osaka, Japan (Y.Koy., A.U., K.A., K.I., K.T., Y.Kot.); and Department of Clinical Pharmacy, School of Pharmaceutical Sciences, Kobe Gakuin University, Minatojima, Kobe, Japan (S.T.)
| | - Kana Abe
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tonda-bayashi, Osaka, Japan (Y.Koy., A.U., K.A., K.I., K.T., Y.Kot.); and Department of Clinical Pharmacy, School of Pharmaceutical Sciences, Kobe Gakuin University, Minatojima, Kobe, Japan (S.T.)
| | - Kuniaki Iwamae
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tonda-bayashi, Osaka, Japan (Y.Koy., A.U., K.A., K.I., K.T., Y.Kot.); and Department of Clinical Pharmacy, School of Pharmaceutical Sciences, Kobe Gakuin University, Minatojima, Kobe, Japan (S.T.)
| | - Shogo Tokuyama
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tonda-bayashi, Osaka, Japan (Y.Koy., A.U., K.A., K.I., K.T., Y.Kot.); and Department of Clinical Pharmacy, School of Pharmaceutical Sciences, Kobe Gakuin University, Minatojima, Kobe, Japan (S.T.)
| | - Keisuke Tanaka
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tonda-bayashi, Osaka, Japan (Y.Koy., A.U., K.A., K.I., K.T., Y.Kot.); and Department of Clinical Pharmacy, School of Pharmaceutical Sciences, Kobe Gakuin University, Minatojima, Kobe, Japan (S.T.)
| | - Yuki Kotake
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tonda-bayashi, Osaka, Japan (Y.Koy., A.U., K.A., K.I., K.T., Y.Kot.); and Department of Clinical Pharmacy, School of Pharmaceutical Sciences, Kobe Gakuin University, Minatojima, Kobe, Japan (S.T.)
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305
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Transformation of Astrocytes to a Neuroprotective Phenotype by Microglia via P2Y 1 Receptor Downregulation. Cell Rep 2017; 19:1151-1164. [DOI: 10.1016/j.celrep.2017.04.047] [Citation(s) in RCA: 191] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2016] [Revised: 03/07/2017] [Accepted: 04/14/2017] [Indexed: 11/22/2022] Open
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306
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Delayed histochemical alterations within the neurovascular unit due to transient focal cerebral ischemia and experimental treatment with neurotrophic factors. PLoS One 2017; 12:e0174996. [PMID: 28445478 PMCID: PMC5405989 DOI: 10.1371/journal.pone.0174996] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2016] [Accepted: 03/17/2017] [Indexed: 02/03/2023] Open
Abstract
Current stroke therapy is focused on recanalizing strategies, but neuroprotective co-treatments are still lacking. Modern concepts of the ischemia-affected neurovascular unit (NVU) and surrounding penumbra emphasize the complexity during the transition from initial damaging to regenerative processes. While early treatment with neurotrophic factors was shown to result in lesion size reduction and blood-brain barrier (BBB) stabilization, cellular consequences from these treatments are poorly understood. This study explored delayed cellular responses not only to ischemic stroke, but also to an early treatment with neurotrophic factors. Rats underwent 60 minutes of focal cerebral ischemia. Fluorescence labeling was applied to sections from brains perfused 7 days after ischemia. Analyses focused on NVU constituents including the vasculature, astrocytes and microglia in the ischemic striatum, the border zone and the contralateral hemisphere. In addition to histochemical signs of BBB breakdown, a strong up-regulation of collagen IV and microglia activation occurred within the ischemic core with simultaneous degradation of astrocytes and their endfeet. Activated astroglia were mainly depicted at the border zone in terms of a glial scar formation. Early treatment with pigment epithelium-derived factor (PEDF) resulted in an attenuation of the usually up-regulated collagen IV-immunoreactivity. However, glial activation was not influenced by treatment with PEDF or the epidermal growth factor (EGF). In conclusion, these data on ischemia-induced cellular reactions within the NVU might help to develop treatments addressing the transition from injury towards regeneration. Thereby, the integrity of the vasculature in close relation to neighboring structures like astrocytes appears as a promising target.
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307
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Microglial TNFα Induces COX2 and PGI2 Synthase Expression in Spinal Endothelial Cells during Neuropathic Pain. eNeuro 2017; 4:eN-NWR-0064-17. [PMID: 28451639 PMCID: PMC5399753 DOI: 10.1523/eneuro.0064-17.2017] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 03/28/2017] [Accepted: 04/06/2017] [Indexed: 02/07/2023] Open
Abstract
Prostaglandins (PGs) are typical lipid mediators that play a role in homeostasis and disease. They are synthesized from arachidonic acid by cyclooxygenase 1 (COX1) and COX2. Although COX2 has been reported to be upregulated in the spinal cord after nerve injury, its expression and functional roles in neuropathic pain remain unclear. In this study, we investigated the expression of Cox2, PGI2 synthase (Pgis), and prostaglandin I2 receptor (IP receptor) mRNA in the rat spinal cord after spared nerve injury (SNI). Levels of Cox2 and Pgis mRNA increased in endothelial cells from 24 to 48 h after nerve injury. IP receptor mRNA was constitutively expressed in dorsal horn neurons. A COX2 inhibitor and IP receptor antagonists attenuated pain behavior in the early phase of neuropathic pain. Furthermore, we examined the relationship between COX2 and tumor necrosis factor-α (TNFα) in the spinal cord of a rat SNI model. Levels of TNFα mRNA transiently increased in the spinal microglia 24 h after SNI. The TNF receptors Tnfr1 and Tnfr2 mRNA were colocalized with COX2. Intrathecal injection of TNFα induced Cox2 and Pgis mRNA expression in endothelial cells. These results revealed that microglia-derived TNFα induced COX2 and PGIS expression in spinal endothelial cells and that endothelial PGI2 played a critical role in neuropathic pain via neuronal IP receptor. These findings further suggest that the glia–endothelial cell interaction of the neurovascular unit via transient TNFα is involved in the generation of neuropathic pain.
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308
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Haddad-Tóvolli R, Dragano NRV, Ramalho AFS, Velloso LA. Development and Function of the Blood-Brain Barrier in the Context of Metabolic Control. Front Neurosci 2017; 11:224. [PMID: 28484368 PMCID: PMC5399017 DOI: 10.3389/fnins.2017.00224] [Citation(s) in RCA: 128] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 04/04/2017] [Indexed: 12/21/2022] Open
Abstract
Under physiological conditions, the brain consumes over 20% of the whole body energy supply. The blood-brain barrier (BBB) allows dynamic interactions between blood capillaries and the neuronal network in order to provide an adequate control of molecules that are transported in and out of the brain. Alterations in the BBB structure and function affecting brain accessibility to nutrients and exit of toxins are found in a number of diseases, which in turn may disturb brain function and nutrient signaling. In this review we explore the major advances obtained in the understanding of the BBB development and how its structure impacts on function. Furthermore, we focus on the particularities of the barrier permeability in the hypothalamus, its role in metabolic control and the potential impact of hypothalamic BBB abnormities in metabolic related diseases.
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Affiliation(s)
- Roberta Haddad-Tóvolli
- Laboratory of Cell Signaling and Obesity and Comorbidities Research Center, Faculty of Medical Sciences, University of CampinasCampinas, Brazil
| | | | | | - Licio A. Velloso
- Laboratory of Cell Signaling and Obesity and Comorbidities Research Center, Faculty of Medical Sciences, University of CampinasCampinas, Brazil
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309
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Gao X, Wang YC, Liu Y, Yue Q, Liu Z, Ke M, Zhao S, Li C. Nanoagonist-mediated endothelial tight junction opening: A strategy for safely increasing brain drug delivery in mice. J Cereb Blood Flow Metab 2017; 37:1410-1424. [PMID: 27342320 PMCID: PMC5453461 DOI: 10.1177/0271678x16656198] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Even though opening endothelial tight junctions is an efficient way to up-regulate brain drug delivery, the extravasation of blood-borne components from the compromised tight junctions can result in adverse consequences such as edema and neuronal injuries. In this work, we developed a nanoagonist that temporarily opened tight junctions by signaling adenosine 2A receptor, a type of G protein-coupled receptor expressed on brain capillary endothelial cells. Magnetic resonance imaging demonstrated remarkable blood-brain barrier permeability enhancements and significantly increased brain uptakes of both small molecular and macromolecular paramagnetic agents after nanoagonist administration. Gamma ray imaging and transmission electron microscope observed tight junction opening followed by spontaneous recovery after nanoagonist treatment. Immunofluorescence staining showed the unspoiled basal membrane, pericytes and astrocyte endfeet that enwrapped the vascular endothelium. Importantly, edema, apoptosis and neuronal injuries observed after hypertonic agent mediated tight junction-opening were not observed after nanoagonist intervention. The uncompromised neurovascular units may prevent the leakage of blood-borne constituents into brain parenchyma and accelerate tight junction recovery. Considering blood-brain barrier impermeability is a major obstacle in the treatment of central nervous system diseases, nanoagonist-mediated tight junction opening provides a promising strategy to enhance brain drug delivery with minimized adverse effects.
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Affiliation(s)
- Xihui Gao
- 1 Key Laboratory of Smart Drug Delivery, Ministry of Education, School of Pharmacy, Fudan University, Shanghai, China
| | - Yuan-Cheng Wang
- 2 Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Zhongda Hospital, Medical School of Southeast University, Nanjing, China
| | - Yikang Liu
- 3 Department of Biomedical Engineering, The Pennsylvania State University, Philadelphia, PA, USA
| | - Qi Yue
- 4 Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China
| | - Zining Liu
- 1 Key Laboratory of Smart Drug Delivery, Ministry of Education, School of Pharmacy, Fudan University, Shanghai, China
| | - Mengjing Ke
- 1 Key Laboratory of Smart Drug Delivery, Ministry of Education, School of Pharmacy, Fudan University, Shanghai, China
| | - Shengyuan Zhao
- 1 Key Laboratory of Smart Drug Delivery, Ministry of Education, School of Pharmacy, Fudan University, Shanghai, China
| | - Cong Li
- 1 Key Laboratory of Smart Drug Delivery, Ministry of Education, School of Pharmacy, Fudan University, Shanghai, China
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310
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Translation in astrocyte distal processes sets molecular heterogeneity at the gliovascular interface. Cell Discov 2017; 3:17005. [PMID: 28377822 PMCID: PMC5368712 DOI: 10.1038/celldisc.2017.5] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Accepted: 01/10/2017] [Indexed: 12/26/2022] Open
Abstract
Astrocytes send out long processes that are terminated by endfeet at the vascular surface and regulate vascular functions as well as homeostasis at the vascular interface. To date, the astroglial mechanisms underlying these functions have been poorly addressed. Here we demonstrate that a subset of messenger RNAs is distributed in astrocyte endfeet. We identified, among this transcriptome, a pool of messenger RNAs bound to ribosomes, the endfeetome, that primarily encodes for secreted and membrane proteins. We detected nascent protein synthesis in astrocyte endfeet. Finally, we determined the presence of smooth and rough endoplasmic reticulum and the Golgi apparatus in astrocyte perivascular processes and endfeet, suggesting for local maturation of membrane and secreted proteins. These results demonstrate for the first time that protein synthesis occurs in astrocyte perivascular distal processes that may sustain their structural and functional polarization at the vascular interface.
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311
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Freire-Regatillo A, Argente-Arizón P, Argente J, García-Segura LM, Chowen JA. Non-Neuronal Cells in the Hypothalamic Adaptation to Metabolic Signals. Front Endocrinol (Lausanne) 2017; 8:51. [PMID: 28377744 PMCID: PMC5359311 DOI: 10.3389/fendo.2017.00051] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 03/03/2017] [Indexed: 12/19/2022] Open
Abstract
Although the brain is composed of numerous cell types, neurons have received the vast majority of attention in the attempt to understand how this organ functions. Neurons are indeed fundamental but, in order for them to function correctly, they rely on the surrounding "non-neuronal" cells. These different cell types, which include glia, epithelial cells, pericytes, and endothelia, supply essential substances to neurons, in addition to protecting them from dangerous substances and situations. Moreover, it is now clear that non-neuronal cells can also actively participate in determining neuronal signaling outcomes. Due to the increasing problem of obesity in industrialized countries, investigation of the central control of energy balance has greatly increased in attempts to identify new therapeutic targets. This has led to interesting advances in our understanding of how appetite and systemic metabolism are modulated by non-neuronal cells. For example, not only are nutrients and hormones transported into the brain by non-neuronal cells, but these cells can also metabolize these metabolic factors, thus modifying the signals reaching the neurons. The hypothalamus is the main integrating center of incoming metabolic and hormonal signals and interprets this information in order to control appetite and systemic metabolism. Hence, the factors transported and released from surrounding non-neuronal cells will undoubtedly influence metabolic homeostasis. This review focuses on what is known to date regarding the involvement of different cell types in the transport and metabolism of nutrients and hormones in the hypothalamus. The possible involvement of non-neuronal cells, in particular glial cells, in physiopathological outcomes of poor dietary habits and excess weight gain are also discussed.
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Affiliation(s)
- Alejandra Freire-Regatillo
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación la Princesa, Madrid, Spain
- Department of Pediatrics, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
- Centro de Investigación Biomédica en Red: Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Madrid, Spain
| | - Pilar Argente-Arizón
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación la Princesa, Madrid, Spain
- Department of Pediatrics, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
- Centro de Investigación Biomédica en Red: Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Madrid, Spain
| | - Jesús Argente
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación la Princesa, Madrid, Spain
- Department of Pediatrics, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
- Centro de Investigación Biomédica en Red: Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Madrid, Spain
- IMDEA Food Institute, Campus of International Excellence (CEI) UAM + CSIC, Madrid, Spain
| | - Luis Miguel García-Segura
- Laboratory of Neuroactive Steroids, Department of Functional and Systems Neurobiology, Instituto Cajal, CSIC (Consejo Superior de Investigaciones Científicas), Madrid, Spain
- Centro de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable (CIBERFES), Madrid, Spain
| | - Julie A. Chowen
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación la Princesa, Madrid, Spain
- Centro de Investigación Biomédica en Red: Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Madrid, Spain
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312
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miR-285-Yki/Mask double-negative feedback loop mediates blood-brain barrier integrity in Drosophila. Proc Natl Acad Sci U S A 2017; 114:E2365-E2374. [PMID: 28265104 DOI: 10.1073/pnas.1613233114] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The Hippo signaling pathway is highly conserved from Drosophila to mammals and plays a central role in maintaining organ size and tissue homeostasis. The blood-brain barrier (BBB) physiologically isolates the brain from circulating blood or the hemolymph system, and its integrity is strictly maintained to perform sophisticated neuronal functions. Until now, the underlying mechanisms of subperineurial glia (SPG) growth and BBB maintenance during development are not clear. Here, we report an miR-285-Yorkie (Yki)/Multiple Ankyrin repeats Single KH domain (Mask) double-negative feedback loop that regulates SPG growth and BBB integrity. Flies with a loss of miR-285 have a defective BBB with increased SPG ploidy and disruptive septate junctions. Mechanistically, miR-285 directly targets the Yki cofactor Mask to suppress Yki activity and down-regulates the expression of its downstream target cyclin E, a key regulator of cell cycle. Disturbance of cyclin E expression in SPG causes abnormal endoreplication, which leads to aberrant DNA ploidy and defective septate junctions. Moreover, the expression of miR-285 is increased by knockdown of yki or mask and is decreased with yki overexpression, thus forming a double-negative feedback loop. This regulatory loop is crucial for sustaining an appropriate Yki/Mask activity and cyclin E level to maintain SPG ploidy and BBB integrity. Perturbation of this signaling loop, either by dysregulated miR-285 expression or Yki activity, causes irregular SPG ploidy and BBB disruption. Furthermore, ectopic expression of miR-285 promotes canonical Hippo pathway-mediated apoptosis independent of the p53 or JNK pathway. Collectively, these results reveal an exquisite regulatory mechanism for BBB maintenance through an miR-285-Yki/Mask regulatory circuit.
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313
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Laquinimod enhances central nervous system barrier functions. Neurobiol Dis 2017; 102:60-69. [PMID: 28235673 DOI: 10.1016/j.nbd.2017.02.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2016] [Revised: 12/22/2016] [Accepted: 02/20/2017] [Indexed: 12/30/2022] Open
Abstract
Laquinimod is currently being tested as a therapeutic drug in multiple sclerosis. However, its exact mechanism of action is still under investigation. Tracking of fluorescently-tagged encephalitogenic T cells during experimental autoimmune encephalomyelitis (EAE), an animal model for multiple sclerosis, revealed that laquinimod significantly reduces the invasion of pathogenic effector T cells into the CNS tissue. T-cell activation, differentiation and amplification within secondary lymphoid organs after immunization with myelin antigen, their migratory capacity and re-activation within the nervous tissue were either only mildly affected or remained unchanged. Instead, laquinimod directly impacted the functionality of the CNS vasculature. The expression of tight junction proteins p120 and ZO-1 in human brain endothelial cells was up-regulated upon laquinimod treatment, resulting in a significant increase in the transendothelial electrical resistance of confluent monolayers of brain endothelial cells. Similarly, expression of the adhesion molecule activated leukocyte cell adhesion molecule (ALCAM) and inflammatory chemokines CCL2 and IP-10 was suppressed, leading to a significant reduction in the migration of memory TH1 and TH17 lymphocytes across the blood brain barrier (BBB). Our data indicate that laquinimod exerts its therapeutic effects by tightening the BBB and limiting parenchymal invasion of effector T cells, thereby reducing CNS damage.
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314
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Saunus JM, McCart Reed AE, Lim ZL, Lakhani SR. Breast Cancer Brain Metastases: Clonal Evolution in Clinical Context. Int J Mol Sci 2017; 18:ijms18010152. [PMID: 28098771 PMCID: PMC5297785 DOI: 10.3390/ijms18010152] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 12/22/2016] [Accepted: 12/27/2016] [Indexed: 02/01/2023] Open
Abstract
Brain metastases are highly-evolved manifestations of breast cancer arising in a unique microenvironment, giving them exceptional adaptability in the face of new extrinsic pressures. The incidence is rising in line with population ageing, and use of newer therapies that stabilise metastatic disease burden with variable efficacy throughout the body. Historically, there has been a widely-held view that brain metastases do not respond to circulating therapeutics because the blood-brain-barrier (BBB) restricts their uptake. However, emerging data are beginning to paint a more complex picture where the brain acts as a sanctuary for dormant, subclinical proliferations that are initially protected by the BBB, but then exposed to dynamic selection pressures as tumours mature and vascular permeability increases. Here, we review key experimental approaches and landmark studies that have charted the genomic landscape of breast cancer brain metastases. These findings are contextualised with the factors impacting on clonal outgrowth in the brain: intrinsic breast tumour cell capabilities required for brain metastatic fitness, and the neural niche, which is initially hostile to invading cells but then engineered into a tumour-support vehicle by the successful minority. We also discuss how late detection, abnormal vascular perfusion and interstitial fluid dynamics underpin the recalcitrant clinical behaviour of brain metastases, and outline active clinical trials in the context of precision management.
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Affiliation(s)
- Jodi M Saunus
- The University of Queensland (UQ), UQ Centre for Clinical Research, Herston, Queensland 4029, Australia.
- QIMR Berghofer Medical Research Institute, Herston, Queensland 4006, Australia.
| | - Amy E McCart Reed
- The University of Queensland (UQ), UQ Centre for Clinical Research, Herston, Queensland 4029, Australia.
- QIMR Berghofer Medical Research Institute, Herston, Queensland 4006, Australia.
| | - Zhun Leong Lim
- The University of Queensland (UQ), UQ Centre for Clinical Research, Herston, Queensland 4029, Australia.
- QIMR Berghofer Medical Research Institute, Herston, Queensland 4006, Australia.
| | - Sunil R Lakhani
- The University of Queensland (UQ), UQ Centre for Clinical Research, Herston, Queensland 4029, Australia.
- Pathology Queensland, Royal Brisbane Women's Hospital, Herston, Queensland 4029, Australia.
- UQ School of Medicine, Herston, Queensland 4006, Australia.
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315
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Michinaga S, Koyama Y. Protection of the Blood–Brain Barrier as a Therapeutic Strategy for Brain Damage. Biol Pharm Bull 2017; 40:569-575. [DOI: 10.1248/bpb.b16-00991] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Shotaro Michinaga
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University
| | - Yutaka Koyama
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University
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316
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317
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García-Cáceres C, Quarta C, Varela L, Gao Y, Gruber T, Legutko B, Jastroch M, Johansson P, Ninkovic J, Yi CX, Le Thuc O, Szigeti-Buck K, Cai W, Meyer CW, Pfluger PT, Fernandez AM, Luquet S, Woods SC, Torres-Alemán I, Kahn CR, Götz M, Horvath TL, Tschöp MH. Astrocytic Insulin Signaling Couples Brain Glucose Uptake with Nutrient Availability. Cell 2016; 166:867-880. [PMID: 27518562 DOI: 10.1016/j.cell.2016.07.028] [Citation(s) in RCA: 345] [Impact Index Per Article: 43.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 05/31/2016] [Accepted: 07/19/2016] [Indexed: 12/14/2022]
Abstract
We report that astrocytic insulin signaling co-regulates hypothalamic glucose sensing and systemic glucose metabolism. Postnatal ablation of insulin receptors (IRs) in glial fibrillary acidic protein (GFAP)-expressing cells affects hypothalamic astrocyte morphology, mitochondrial function, and circuit connectivity. Accordingly, astrocytic IR ablation reduces glucose-induced activation of hypothalamic pro-opio-melanocortin (POMC) neurons and impairs physiological responses to changes in glucose availability. Hypothalamus-specific knockout of astrocytic IRs, as well as postnatal ablation by targeting glutamate aspartate transporter (GLAST)-expressing cells, replicates such alterations. A normal response to altering directly CNS glucose levels in mice lacking astrocytic IRs indicates a role in glucose transport across the blood-brain barrier (BBB). This was confirmed in vivo in GFAP-IR KO mice by using positron emission tomography and glucose monitoring in cerebral spinal fluid. We conclude that insulin signaling in hypothalamic astrocytes co-controls CNS glucose sensing and systemic glucose metabolism via regulation of glucose uptake across the BBB.
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Affiliation(s)
- Cristina García-Cáceres
- Helmholtz Diabetes Center (HDC) & German Center for Diabetes Research (DZD), Helmholtz Zentrum München, 85764 Neuherberg, Germany; Division of Metabolic Diseases, Technische Universität München, 80333 Munich, Germany
| | - Carmelo Quarta
- Helmholtz Diabetes Center (HDC) & German Center for Diabetes Research (DZD), Helmholtz Zentrum München, 85764 Neuherberg, Germany; Division of Metabolic Diseases, Technische Universität München, 80333 Munich, Germany
| | - Luis Varela
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Section of Comparative Medicine, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Yuanqing Gao
- Helmholtz Diabetes Center (HDC) & German Center for Diabetes Research (DZD), Helmholtz Zentrum München, 85764 Neuherberg, Germany; Division of Metabolic Diseases, Technische Universität München, 80333 Munich, Germany
| | - Tim Gruber
- Helmholtz Diabetes Center (HDC) & German Center for Diabetes Research (DZD), Helmholtz Zentrum München, 85764 Neuherberg, Germany; Division of Metabolic Diseases, Technische Universität München, 80333 Munich, Germany
| | - Beata Legutko
- Helmholtz Diabetes Center (HDC) & German Center for Diabetes Research (DZD), Helmholtz Zentrum München, 85764 Neuherberg, Germany; Division of Metabolic Diseases, Technische Universität München, 80333 Munich, Germany
| | - Martin Jastroch
- Helmholtz Diabetes Center (HDC) & German Center for Diabetes Research (DZD), Helmholtz Zentrum München, 85764 Neuherberg, Germany; Division of Metabolic Diseases, Technische Universität München, 80333 Munich, Germany
| | - Pia Johansson
- Institute of Stem Cell Research Center, Helmholtz Zentrum München, 85764 Neuherberg, Germany; Physiological Genomics, Biomedical Center, Ludwigs-Maximilians-University, 80336 Munich, Germany; 7SYNERGY, Excellence Cluster Systems Neurology, Biomedical Center, Ludwigs-Maximilians-University, 80336 Munich, Germany
| | - Jovica Ninkovic
- Institute of Stem Cell Research Center, Helmholtz Zentrum München, 85764 Neuherberg, Germany; Physiological Genomics, Biomedical Center, Ludwigs-Maximilians-University, 80336 Munich, Germany; 7SYNERGY, Excellence Cluster Systems Neurology, Biomedical Center, Ludwigs-Maximilians-University, 80336 Munich, Germany
| | - Chun-Xia Yi
- Helmholtz Diabetes Center (HDC) & German Center for Diabetes Research (DZD), Helmholtz Zentrum München, 85764 Neuherberg, Germany; Division of Metabolic Diseases, Technische Universität München, 80333 Munich, Germany
| | - Ophelia Le Thuc
- Helmholtz Diabetes Center (HDC) & German Center for Diabetes Research (DZD), Helmholtz Zentrum München, 85764 Neuherberg, Germany; Division of Metabolic Diseases, Technische Universität München, 80333 Munich, Germany
| | - Klara Szigeti-Buck
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Section of Comparative Medicine, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Weikang Cai
- Section of Integrative Physiology and Metabolism, Joslin Diabetes Center and Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Carola W Meyer
- Helmholtz Diabetes Center (HDC) & German Center for Diabetes Research (DZD), Helmholtz Zentrum München, 85764 Neuherberg, Germany; Division of Metabolic Diseases, Technische Universität München, 80333 Munich, Germany
| | - Paul T Pfluger
- Helmholtz Diabetes Center (HDC) & German Center for Diabetes Research (DZD), Helmholtz Zentrum München, 85764 Neuherberg, Germany; Division of Metabolic Diseases, Technische Universität München, 80333 Munich, Germany
| | | | - Serge Luquet
- Université Paris Diderot, Sorbonne Paris Cité, Unité de Biologie Fonctionnelle et Adaptative, CNRS UMR 8251, 75205 Paris, France
| | - Stephen C Woods
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, 2170 Galbraith Avenue, Cincinnati, OH 45237, USA
| | | | - C Ronald Kahn
- Section of Integrative Physiology and Metabolism, Joslin Diabetes Center and Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Magdalena Götz
- Institute of Stem Cell Research Center, Helmholtz Zentrum München, 85764 Neuherberg, Germany; Physiological Genomics, Biomedical Center, Ludwigs-Maximilians-University, 80336 Munich, Germany; 7SYNERGY, Excellence Cluster Systems Neurology, Biomedical Center, Ludwigs-Maximilians-University, 80336 Munich, Germany
| | - Tamas L Horvath
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Section of Comparative Medicine, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Matthias H Tschöp
- Helmholtz Diabetes Center (HDC) & German Center for Diabetes Research (DZD), Helmholtz Zentrum München, 85764 Neuherberg, Germany; Division of Metabolic Diseases, Technische Universität München, 80333 Munich, Germany.
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318
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McConnell HL, Kersch CN, Woltjer RL, Neuwelt EA. The Translational Significance of the Neurovascular Unit. J Biol Chem 2016; 292:762-770. [PMID: 27920202 DOI: 10.1074/jbc.r116.760215] [Citation(s) in RCA: 183] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The mammalian brain is supplied with blood by specialized vasculature that is structurally and functionally distinct from that of the periphery. A defining feature of this vasculature is a physical blood-brain barrier (BBB). The BBB separates blood components from the brain microenvironment, regulating the entry and exit of ions, nutrients, macromolecules, and energy metabolites. Over the last two decades, physiological studies of cerebral blood flow dynamics have demonstrated that substantial intercellular communication occurs between cells of the vasculature and the neurons and glia that abut the vasculature. These findings suggest that the BBB does not function independently, but as a module within the greater context of a multicellular neurovascular unit (NVU) that includes neurons, astrocytes, pericytes, and microglia as well as the blood vessels themselves. Here, we describe the roles of these NVU components as well as how they act in concert to modify cerebrovascular function and permeability in health and in select diseases.
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Affiliation(s)
- Heather L McConnell
- From the Departments of Neurology, Pathology, Neurosurgery, and Veterans Affairs, Oregon Health & Science University, Portland, Oregon 97239-2941
| | - Cymon N Kersch
- From the Departments of Neurology, Pathology, Neurosurgery, and Veterans Affairs, Oregon Health & Science University, Portland, Oregon 97239-2941
| | - Randall L Woltjer
- From the Departments of Neurology, Pathology, Neurosurgery, and Veterans Affairs, Oregon Health & Science University, Portland, Oregon 97239-2941
| | - Edward A Neuwelt
- From the Departments of Neurology, Pathology, Neurosurgery, and Veterans Affairs, Oregon Health & Science University, Portland, Oregon 97239-2941
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319
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Chakraborty A, de Wit NM, van der Flier WM, de Vries HE. The blood brain barrier in Alzheimer's disease. Vascul Pharmacol 2016; 89:12-18. [PMID: 27894893 DOI: 10.1016/j.vph.2016.11.008] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Revised: 11/17/2016] [Accepted: 11/20/2016] [Indexed: 12/13/2022]
Abstract
Alzheimer's disease (AD) is the most common form of dementia, affecting millions of people worldwide. One of the prominent causative factors of AD pathogenesis is cerebral vascular dysfunction, which results in diminished cerebral perfusion. Moreover, due to the loss of the protective function of the blood-brain barrier (BBB), impaired clearance of excess neurotoxic amyloid beta (Aβ) occurs, causing vascular perturbation and diminished cognitive functioning. The relationship between the prevalence of AD and vascular risk factors is complex and not fully understood. In this review we illustrate the vascular risk factors, their effects on BBB function and their contributions to the onset of AD. Additionally, we discuss the underlying factors that may lead to altered neurovascular function and/or cerebral hypoperfusion in AD.
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Affiliation(s)
- A Chakraborty
- Blood-brain barrier research group, Department of Molecular Cell Biology and Immunology, Neuroscience Campus Amsterdam, VU University Medical Center, P.O. Box 7057, 1007, MB Amsterdam, The Netherlands.
| | - N M de Wit
- Blood-brain barrier research group, Department of Molecular Cell Biology and Immunology, Neuroscience Campus Amsterdam, VU University Medical Center, P.O. Box 7057, 1007, MB Amsterdam, The Netherlands
| | - W M van der Flier
- Alzheimer Center and Department of Neurology, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, the Netherlands;; Department of Epidemiology and Biostatistics, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, the Netherlands
| | - H E de Vries
- Blood-brain barrier research group, Department of Molecular Cell Biology and Immunology, Neuroscience Campus Amsterdam, VU University Medical Center, P.O. Box 7057, 1007, MB Amsterdam, The Netherlands
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320
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Langer J, Gerkau NJ, Derouiche A, Kleinhans C, Moshrefi-Ravasdjani B, Fredrich M, Kafitz KW, Seifert G, Steinhäuser C, Rose CR. Rapid sodium signaling couples glutamate uptake to breakdown of ATP in perivascular astrocyte endfeet. Glia 2016; 65:293-308. [PMID: 27785828 DOI: 10.1002/glia.23092] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 10/05/2016] [Accepted: 10/06/2016] [Indexed: 12/19/2022]
Abstract
Perivascular endfeet of astrocytes are highly polarized compartments that ensheath blood vessels and contribute to the blood-brain barrier. They experience calcium transients with neuronal activity, a phenomenon involved in neurovascular coupling. Endfeet also mediate the uptake of glucose from the blood, a process stimulated in active brain regions. Here, we demonstrate in mouse hippocampal tissue slices that endfeet undergo sodium signaling upon stimulation of glutamatergic synaptic activity. Glutamate-induced endfeet sodium transients were diminished by TFB-TBOA, suggesting that they were generated by sodium-dependent glutamate uptake. With local agonist application, they could be restricted to endfeet and immunohistochemical analysis revealed prominent expression of glutamate transporters GLAST and GLT-1 localized towards the neuropil vs. the vascular side of endfeet. Endfeet sodium signals spread at an apparent maximum velocity of ∼120 µm/s and directly propagated from stimulated into neighboring endfeet; this spread was omitted in Cx30/Cx43 double-deficient mice. Sodium transients resulted in elevation of intracellular magnesium, indicating a decrease in intracellular ATP. In summary, our results establish that excitatory synaptic activity and stimulation of glutamate uptake in astrocytes trigger transient sodium increases in perivascular endfeet which rapidly spread through gap junctions into neighboring endfeet and cause a reduction of intracellular ATP. The newly discovered endfeet sodium signaling thereby represents a fast, long-lived and inter-cellularly acting indicator of synaptic activity at the blood-brain barrier, which likely constitutes an important component of neuro-metabolic coupling in the brain. GLIA 2017;65:293-308.
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Affiliation(s)
- Julia Langer
- Faculty of Mathematics and Natural Sciences, Institute of Neurobiology, Heinrich Heine University Duesseldorf, Universitätsstrasse 1, Duesseldorf, D-40225, Germany
| | - Niklas J Gerkau
- Faculty of Mathematics and Natural Sciences, Institute of Neurobiology, Heinrich Heine University Duesseldorf, Universitätsstrasse 1, Duesseldorf, D-40225, Germany
| | - Amin Derouiche
- Institute of Anatomy II and Dr. Senckenbergisches Chronomedizinisches Institut, Goethe-University of Frankfurt, Theodor-Stern-Kai 7, Frankfurt/M, D-60590, Germany
| | - Christian Kleinhans
- Faculty of Mathematics and Natural Sciences, Institute of Neurobiology, Heinrich Heine University Duesseldorf, Universitätsstrasse 1, Duesseldorf, D-40225, Germany
| | - Behrouz Moshrefi-Ravasdjani
- Faculty of Mathematics and Natural Sciences, Institute of Neurobiology, Heinrich Heine University Duesseldorf, Universitätsstrasse 1, Duesseldorf, D-40225, Germany
| | - Michaela Fredrich
- Institute of Anatomy II and Dr. Senckenbergisches Chronomedizinisches Institut, Goethe-University of Frankfurt, Theodor-Stern-Kai 7, Frankfurt/M, D-60590, Germany
| | - Karl W Kafitz
- Faculty of Mathematics and Natural Sciences, Institute of Neurobiology, Heinrich Heine University Duesseldorf, Universitätsstrasse 1, Duesseldorf, D-40225, Germany
| | - Gerald Seifert
- Medical Faculty, Institute of Cellular Neurosciences, University of Bonn, Bonn, D-53105, Germany
| | - Christian Steinhäuser
- Medical Faculty, Institute of Cellular Neurosciences, University of Bonn, Bonn, D-53105, Germany
| | - Christine R Rose
- Faculty of Mathematics and Natural Sciences, Institute of Neurobiology, Heinrich Heine University Duesseldorf, Universitätsstrasse 1, Duesseldorf, D-40225, Germany
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321
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Menzel L, Kleber L, Friedrich C, Hummel R, Dangel L, Winter J, Schmitz K, Tegeder I, Schäfer MKE. Progranulin protects against exaggerated axonal injury and astrogliosis following traumatic brain injury. Glia 2016; 65:278-292. [DOI: 10.1002/glia.23091] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 10/04/2016] [Indexed: 12/16/2022]
Affiliation(s)
- Lutz Menzel
- Department of Anesthesiology; University Medical Center, Johannes Gutenberg-University, Mainz; Germany
| | - Lisa Kleber
- Department of Anesthesiology; University Medical Center, Johannes Gutenberg-University, Mainz; Germany
| | - Carina Friedrich
- Department of Anesthesiology; University Medical Center, Johannes Gutenberg-University, Mainz; Germany
| | - Regina Hummel
- Department of Anesthesiology; University Medical Center, Johannes Gutenberg-University, Mainz; Germany
| | - Larissa Dangel
- Department of Anesthesiology; University Medical Center, Johannes Gutenberg-University, Mainz; Germany
| | - Jennifer Winter
- Institute of Human Genetics, University Medical Center, Johannes Gutenberg-University, Mainz; Germany
- Focus Program Translational Neurosciences (FTN) of the Johannes Gutenberg-University, Mainz; Germany
| | - Katja Schmitz
- Clinical Pharmacology; Goethe-University Hospital; Frankfurt Germany
| | - Irmgard Tegeder
- Clinical Pharmacology; Goethe-University Hospital; Frankfurt Germany
| | - Michael K. E. Schäfer
- Department of Anesthesiology; University Medical Center, Johannes Gutenberg-University, Mainz; Germany
- Focus Program Translational Neurosciences (FTN) of the Johannes Gutenberg-University, Mainz; Germany
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322
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Filous AR, Silver J. "Targeting astrocytes in CNS injury and disease: A translational research approach". Prog Neurobiol 2016; 144:173-87. [PMID: 27026202 PMCID: PMC5035184 DOI: 10.1016/j.pneurobio.2016.03.009] [Citation(s) in RCA: 108] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Revised: 02/03/2016] [Accepted: 03/03/2016] [Indexed: 12/31/2022]
Abstract
Astrocytes are a major constituent of the central nervous system. These glia play a major role in regulating blood-brain barrier function, the formation and maintenance of synapses, glutamate uptake, and trophic support for surrounding neurons and glia. Therefore, maintaining the proper functioning of these cells is crucial to survival. Astrocyte defects are associated with a wide variety of neuropathological insults, ranging from neurodegenerative diseases to gliomas. Additionally, injury to the CNS causes drastic changes to astrocytes, often leading to a phenomenon known as reactive astrogliosis. This process is important for protecting the surrounding healthy tissue from the spread of injury, while it also inhibits axonal regeneration and plasticity. Here, we discuss the important roles of astrocytes after injury and in disease, as well as potential therapeutic approaches to restore proper astrocyte functioning.
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Affiliation(s)
- Angela R Filous
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH 216-368-4615, United States.
| | - Jerry Silver
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH 216-368-4615, United States.
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323
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Banerjee J, Shi Y, Azevedo HS. In vitro blood–brain barrier models for drug research: state-of-the-art and new perspectives on reconstituting these models on artificial basement membrane platforms. Drug Discov Today 2016; 21:1367-1386. [DOI: 10.1016/j.drudis.2016.05.020] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 05/14/2016] [Accepted: 05/31/2016] [Indexed: 12/21/2022]
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324
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Lasič E, Galland F, Vardjan N, Šribar J, Križaj I, Leite MC, Zorec R, Stenovec M. Time-dependent uptake and trafficking of vesicles capturing extracellular S100B in cultured rat astrocytes. J Neurochem 2016; 139:309-323. [PMID: 27488079 DOI: 10.1111/jnc.13754] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 07/21/2016] [Accepted: 07/26/2016] [Indexed: 01/16/2023]
Abstract
Astrocytes, the most heterogeneous glial cells in the central nervous system, contribute to brain homeostasis, by regulating a myriad of functions, including the clearance of extracellular debris. When cells are damaged, cytoplasmic proteins may exit into the extracellular space. One such protein is S100B, which may exert toxic effects on neighboring cells unless it is removed from the extracellular space, but the mechanisms of this clearance are poorly understood. By using time-lapse confocal microscopy and fluorescently labeled S100B (S100B-Alexa488 ) and fluorescent dextran (Dextran546 ), a fluid phase uptake marker, we examined the uptake of fluorescently labeled S100B-Alexa488 from extracellular space and monitored trafficking of vesicles that internalized S100B-Alexa488 . Initially, S100B-Alexa488 and Dextran546 internalized with distinct rates into different endocytotic vesicles; S100B-Alexa488 internalized into smaller vesicles than Dextran546 . At a later stage, S100B-Alexa488 -positive vesicles substantially co-localized with Dextran546 -positive endolysosomes and with acidic LysoTracker-positive vesicles. Cell treatment with anti-receptor for advanced glycation end products (RAGE) antibody, which binds to RAGE, a 'scavenger receptor', partially inhibited uptake of S100B-Alexa488 , but not of Dextran546 . The dynamin inhibitor dynole 34-2 inhibited internalization of both fluorescent probes. Directional mobility of S100B-Alexa488 -positive vesicles increased over time and was inhibited by ATP stimulation, an agent that increases cytosolic free calcium concentration ([Ca2+ ]i ). We conclude that astrocytes exhibit RAGE- and dynamin-dependent vesicular mechanism to efficiently remove S100B from the extracellular space. If a similar process occurs in vivo, astroglia may mitigate the toxic effects of extracellular S100B by this process under pathophysiologic conditions. This study reveals the vesicular clearance mechanism of extracellular S100B in astrocytes. Initially, fluorescent S100B internalizes into smaller endocytotic vesicles than dextran molecules. At a later stage, both probes co-localize within endolysosomes. S100B internalization is both dynamin- and RAGE-dependent, whereas dextran internalization is dependent on dynamin. Vesicle internalization likely mitigates the toxic effects of extracellular S100B and other waste products.
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Affiliation(s)
- Eva Lasič
- Laboratory of Neuroendocrinology - Molecular Cell Physiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Fabiana Galland
- Laboratory of Neuroendocrinology - Molecular Cell Physiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.,Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Nina Vardjan
- Laboratory of Neuroendocrinology - Molecular Cell Physiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.,Celica Biomedical, Ljubljana, Slovenia
| | - Jernej Šribar
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Ljubljana, Slovenia
| | - Igor Križaj
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Ljubljana, Slovenia.,Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ljubljana, Slovenia
| | - Marina Concli Leite
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Robert Zorec
- Laboratory of Neuroendocrinology - Molecular Cell Physiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia. .,Celica Biomedical, Ljubljana, Slovenia.
| | - Matjaž Stenovec
- Laboratory of Neuroendocrinology - Molecular Cell Physiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia. .,Celica Biomedical, Ljubljana, Slovenia.
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325
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Miyata M, Mandai K, Maruo T, Sato J, Shiotani H, Kaito A, Itoh Y, Wang S, Fujiwara T, Mizoguchi A, Takai Y, Rikitake Y. Localization of nectin-2δ at perivascular astrocytic endfoot processes and degeneration of astrocytes and neurons in nectin-2 knockout mouse brain. Brain Res 2016; 1649:90-101. [PMID: 27545667 DOI: 10.1016/j.brainres.2016.08.023] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2016] [Revised: 08/09/2016] [Accepted: 08/18/2016] [Indexed: 10/21/2022]
Abstract
Nectins are Ca2+-independent immunoglobulin-like cell-cell adhesion molecules. In the nervous system, among four members (nectin-1, -2, -3, and -4), nectin-1 and -3 are asymmetrically localized at puncta adherentia junctions formed between the mossy fiber terminals and the dendrites of CA3 pyramidal neurons in the mouse hippocampus and heterophilic trans-interactions between nectin-1 and nectin-3 are involved in the selective interaction of axons and dendrites of cultured neurons. By contrast, nectin-2, which has two splicing variants, nectin-2α and -2δ, has not been well characterized in the brain. We showed here that nectin-2α was expressed in both cultured mouse neurons and astrocytes whereas nectin-2δ was selectively expressed in the astrocytes. Nectin-2δ was localized at the adhesion sites between adjacent cultured astrocytes, but in the brain it was localized on the plasma membranes of astrocytic perivascular endfoot processes facing the basement membrane of blood vessels. Genetic ablation of nectin-2 caused degeneration of astrocytic perivascular endfoot processes and neurons in the cerebral cortex. These results uncovered for the first time the localization and critical functions of nectin-2 in the brain.
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Affiliation(s)
- Muneaki Miyata
- Division of Signal Transduction, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan; Division of Pathogenetic Signaling, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe 650-0047, Japan
| | - Kenji Mandai
- Division of Pathogenetic Signaling, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe 650-0047, Japan; CREST, Japan Science and Technology Agency, Kobe, Japan
| | - Tomohiko Maruo
- Division of Pathogenetic Signaling, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe 650-0047, Japan; CREST, Japan Science and Technology Agency, Kobe, Japan
| | - Junya Sato
- Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
| | - Hajime Shiotani
- Division of Pathogenetic Signaling, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe 650-0047, Japan; Department of Neurology, Osaka University Graduate School of Medicine, Osaka 565-0871, Japan
| | - Aika Kaito
- CREST, Japan Science and Technology Agency, Kobe, Japan; Department of Neural Regeneration and Cell Communication, Mie University Graduate School of Medicine, Tsu 514-8507, Japan
| | - Yu Itoh
- CREST, Japan Science and Technology Agency, Kobe, Japan; Department of Neural Regeneration and Cell Communication, Mie University Graduate School of Medicine, Tsu 514-8507, Japan
| | - Shujie Wang
- CREST, Japan Science and Technology Agency, Kobe, Japan; Department of Neural Regeneration and Cell Communication, Mie University Graduate School of Medicine, Tsu 514-8507, Japan
| | - Takeshi Fujiwara
- CREST, Japan Science and Technology Agency, Kobe, Japan; Department of Neural Regeneration and Cell Communication, Mie University Graduate School of Medicine, Tsu 514-8507, Japan
| | - Akira Mizoguchi
- CREST, Japan Science and Technology Agency, Kobe, Japan; Department of Neural Regeneration and Cell Communication, Mie University Graduate School of Medicine, Tsu 514-8507, Japan
| | - Yoshimi Takai
- Division of Pathogenetic Signaling, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe 650-0047, Japan; CREST, Japan Science and Technology Agency, Kobe, Japan.
| | - Yoshiyuki Rikitake
- Division of Signal Transduction, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan; CREST, Japan Science and Technology Agency, Kobe, Japan; Department of Medical Pharmaceutics, Kobe Pharmaceutical University, Kobe 658-8558, Japan.
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326
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The multifaceted role of metalloproteinases in physiological and pathological conditions in embryonic and adult brains. Prog Neurobiol 2016; 155:36-56. [PMID: 27530222 DOI: 10.1016/j.pneurobio.2016.08.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 07/10/2016] [Accepted: 08/08/2016] [Indexed: 02/07/2023]
Abstract
Matrix metalloproteinases (MMPs) are a large family of ubiquitous extracellular endopeptidases, which play important roles in a variety of physiological and pathological conditions, from the embryonic stages throughout adult life. Their extraordinary physiological "success" is due to concomitant broad substrate specificities and strict regulation of their expression, activation and inhibition levels. In recent years, MMPs have gained increasing attention as significant effectors in various aspects of central nervous system (CNS) physiology. Most importantly, they have been recognized as main players in a variety of brain disorders having different etiologies and evolution. A common aspect of these pathologies is the development of acute or chronic neuroinflammation. MMPs play an integral part in determining the result of neuroinflammation, in some cases turning its beneficial outcome into a harmful one. This review summarizes the most relevant studies concerning the physiology of MMPs, highlighting their involvement in both the developing and mature CNS, in long-lasting and acute brain diseases and, finally, in nervous system repair. Recently, a concerted effort has been made in identifying therapeutic strategies for major brain diseases by targeting MMP activities. However, from this revision of the literature appears clear that MMPs have multifaceted functional characteristics, which modulate physiological processes in multiple ways and with multiple consequences. Therefore, when choosing MMPs as possible targets, great care must be taken to evaluate the delicate balance between their activation and inhibition and to determine at which stage of the disease and at what level they become active in order maximize chances of success.
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327
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Smoliński Ł, Członkowska A. Cerebral vasomotor reactivity in neurodegenerative diseases. Neurol Neurochir Pol 2016; 50:455-462. [PMID: 27553189 DOI: 10.1016/j.pjnns.2016.07.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 07/26/2016] [Accepted: 07/28/2016] [Indexed: 11/26/2022]
Abstract
Small-caliber cerebral vessels change their diameters in response to alterations of key metabolite concentrations such as carbon dioxide or oxygen. This phenomenon, termed the cerebral vasomotor reactivity (CVMR), is the basis for blood flow regulation in the brain in accordance with its metabolic status. Typically, CVMR is determined as the amount of change in cerebral blood flow in response to a vasodilating stimulus, which can be measured by various neuroimaging methods or by transcranial Doppler. It has been shown that CVMR is impaired in cerebrovascular diseases, but there is also evidence of a similar dysfunction in neurodegenerative disorders. Here, we review studies that have investigated CVMR in the common neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease and multiple sclerosis. Moreover, we discuss potential neurodegenerative mechanisms responsible for the impairment of CVMR.
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Affiliation(s)
- Łukasz Smoliński
- Second Department of Neurology, Institute of Psychiatry and Neurology, Warsaw, Poland
| | - Anna Członkowska
- Second Department of Neurology, Institute of Psychiatry and Neurology, Warsaw, Poland; Department of Clinical and Experimental Pharmacology, Medical University of Warsaw, Warsaw, Poland.
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328
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Boulay AC, Cisternino S, Cohen-Salmon M. Immunoregulation at the gliovascular unit in the healthy brain: A focus on Connexin 43. Brain Behav Immun 2016; 56:1-9. [PMID: 26674996 DOI: 10.1016/j.bbi.2015.11.017] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 10/26/2015] [Accepted: 11/28/2015] [Indexed: 01/18/2023] Open
Abstract
In the brain, immune cell infiltration is normally kept at a very low level and a unique microenvironment strictly restricts immune reactions and inflammation. Even in such quiescent environment, a constant immune surveillance is at work allowing the brain to rapidly react to threats. To date, knowledge about the factors regulating the brain-immune system interrelationship in healthy conditions remains elusive. Interestingly, astrocytes, the most abundant glial cells in the brain, may participate in many aspects of this unique homeostasis, in particular due to their close interaction with the brain vascular system and expression of a specific molecular repertoire. Indeed, astrocytes maintain the blood-brain barrier (BBB) integrity, interact with immune cells, and participate in the regulation of intracerebral liquid movements. We recently showed that Connexin 43 (Cx43), a gap junction protein highly expressed by astrocytes at the BBB interface, is an immunoregulating factor. The absence of astroglial Cx43 leads to a transient endothelial activation, a continuous immune recruitment as well as the development of a specific humoral autoimmune response against the von Willebrand factor A domain-containing protein 5a, an extracellular matrix protein expressed by astrocytes. In this review, we propose to gather current knowledge on how astrocytes may influence the immune system in the healthy brain, focusing on their roles at the gliovascular interface. We will also consider pathological situations involving astrocyte-specific autoimmunities. Finally, we will discuss the specific role of astroglial Cx43 and the physiological consequences of immune regulations taking place on inflammation, cognition and behavior in the absence of Cx43.
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Affiliation(s)
- Anne-Cécile Boulay
- Collège de France, Center for Interdisciplinary Research in Biology (CIRB), Centre National de la Recherche Scientifique CNRS, Unité Mixte de Recherche 7241, Institut National de la Santé et de la Recherche Médicale INSERM, U1050, Neuroglial Interactions in Cerebral Physiopathology, 75231 Paris Cedex 05, France; University Pierre et Marie Curie, ED, N°158, 75005 Paris, France; MEMOLIFE Laboratory of Excellence and Paris Science Lettre Research University, 75005 Paris, France
| | - Salvatore Cisternino
- Variabilité de réponse aux psychotropes, INSERM, U1144, Paris F-75006, France; Université Paris Descartes, Faculté de Pharmacie, UMR-S 1144, 75006 Paris, France; Université Paris Diderot, UMR-S 1144, 75013 Paris, France
| | - Martine Cohen-Salmon
- Collège de France, Center for Interdisciplinary Research in Biology (CIRB), Centre National de la Recherche Scientifique CNRS, Unité Mixte de Recherche 7241, Institut National de la Santé et de la Recherche Médicale INSERM, U1050, Neuroglial Interactions in Cerebral Physiopathology, 75231 Paris Cedex 05, France; University Pierre et Marie Curie, ED, N°158, 75005 Paris, France; MEMOLIFE Laboratory of Excellence and Paris Science Lettre Research University, 75005 Paris, France.
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329
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Orellana JA, Retamal MA, Moraga-Amaro R, Stehberg J. Role of Astroglial Hemichannels and Pannexons in Memory and Neurodegenerative Diseases. Front Integr Neurosci 2016; 10:26. [PMID: 27489539 PMCID: PMC4951483 DOI: 10.3389/fnint.2016.00026] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 07/06/2016] [Indexed: 11/13/2022] Open
Abstract
Under physiological conditions, astroglial hemichannels and pannexons allow the release of gliotransmitters from astrocytes. These gliotransmitters are critical in modulating synaptic transmission, plasticity and memory. However, recent evidence suggests that under pathological conditions, they may be central in the development of various neurodegenerative diseases. Here we review current literature on the role of astroglial hemichannels and pannexons in memory, stress and the development of neurodegenerative diseases, and propose that they are not only crucial for normal brain function, including memory, but also a potential target for the treatment of neurodegenerative diseases.
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Affiliation(s)
- Juan A Orellana
- Departamento de Neurología, Escuela de Medicina, Pontificia Universidad Católica de Chile Santiago, Chile
| | - Mauricio A Retamal
- Centro de Fisiología Celular e Integrativa, Facultad de Medicina, Clínica Alemana Universidad del Desarrollo Santiago, Chile
| | - Rodrigo Moraga-Amaro
- Laboratorio de Neurobiología, Centro de Investigaciones Biomédicas, Universidad Andres Bello Santiago, Chile
| | - Jimmy Stehberg
- Laboratorio de Neurobiología, Centro de Investigaciones Biomédicas, Universidad Andres Bello Santiago, Chile
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330
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Heusinkveld HJ, Wahle T, Campbell A, Westerink RHS, Tran L, Johnston H, Stone V, Cassee FR, Schins RPF. Neurodegenerative and neurological disorders by small inhaled particles. Neurotoxicology 2016; 56:94-106. [PMID: 27448464 DOI: 10.1016/j.neuro.2016.07.007] [Citation(s) in RCA: 197] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 07/18/2016] [Accepted: 07/18/2016] [Indexed: 12/17/2022]
Abstract
The world's population is steadily ageing and as a result, health conditions related to ageing, such as dementia, have become a major public health concern. In 2001, it was estimated that there were almost 5 million Europeans suffering from Alzheimer's disease (AD) and this figure has been projected to almost double by 2040. About 40% of people over 85 suffer from AD, and another 10% from Parkinson's disease (PD). The majority of AD and PD cases are of sporadic origin and environmental factors play an important role in the aetiology. Epidemiological research identified airborne particulate matter (PM) as one of the environmental factors potentially involved in AD and PD pathogenesis. Also, cumulating evidence demonstrates that the smallest sizes of the inhalable fraction of ambient particulate matter, also referred to as ultrafine particulate matter or nano-sized particles, are capable of inducing effects beyond the respiratory system. Translocation of very small particles via the olfactory epithelium in the nose or via uptake into the circulation has been demonstrated through experimental rodent studies with engineered nanoparticles. Outdoor air pollution has been linked to several health effects including oxidative stress and neuroinflammation that may ultimately result in neurodegeneration and cognitive impairment. This review aims to evaluate the relationship between exposure to inhaled ambient particles and neurodegeneration.
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Affiliation(s)
- Harm J Heusinkveld
- IUF-Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany; National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands, The Netherlands; AIR pollutants and Brain Aging research Group.
| | - Tina Wahle
- IUF-Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany; AIR pollutants and Brain Aging research Group
| | - Arezoo Campbell
- College of Pharmacy, Western University of Health Sciences, Pomona, CA, USA
| | - Remco H S Westerink
- Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands
| | - Lang Tran
- Institute of Occupational Medicine, Edinburgh, UK
| | | | - Vicki Stone
- Heriot-Watt University, School of Life Sciences, Edinburgh, UK
| | - Flemming R Cassee
- National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands, The Netherlands; Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands; AIR pollutants and Brain Aging research Group
| | - Roel P F Schins
- IUF-Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany; AIR pollutants and Brain Aging research Group
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331
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Age-Related 1H NMR Characterization of Cerebrospinal Fluid in Newborn and Young Healthy Piglets. PLoS One 2016; 11:e0157623. [PMID: 27391145 PMCID: PMC4938496 DOI: 10.1371/journal.pone.0157623] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Accepted: 06/02/2016] [Indexed: 12/23/2022] Open
Abstract
When it comes to neuroscience, pigs represent an important animal model due to their resemblance with humans’ brains for several patterns including anatomy and developmental stages. Cerebrospinal fluid (CSF) is a relatively easy-to-collect specimen that can provide important information about neurological health and function, proving its importance as both a diagnostic and biomedical monitoring tool. Consequently, it would be of high scientific interest and value to obtain more standard physiological information regarding its composition and dynamics for both swine pathology and the refinement of experimental protocols. Recently, proton nuclear magnetic resonance (1H NMR) spectroscopy has been applied in order to analyze the metabolomic profile of this biological fluid, and results showed the technique to be highly reproducible and reliable. The aim of the present study was to investigate in both qualitative and quantitative manner the composition of Cerebrospinal Fluid harvested form healthy newborn (5 days old-P5) and young (30-P30 and 50-P50 days old) piglets using 1H NMR Spectroscopy, and to analyze any possible difference in metabolites concentration between age groups, related to age and Blood-Brain-Barrier maturation. On each of the analyzed samples, 30 molecules could be observed above their limit of quantification, accounting for 95–98% of the total area of the spectra. The concentrations of adenine, tyrosine, leucine, valine, 3-hydroxyvalerate, 3-methyl-2-oxovalerate were found to decrease between P05 and P50, while the concentrations of glutamine, creatinine, methanol, trimethylamine and myo-inositol were found to increase. The P05-P30 comparison was also significant for glutamine, creatinine, adenine, tyrosine, leucine, valine, 3-hydroxyisovalerate, 3-methyl-2-oxovalerate, while for the P30-P50 comparison we found significant differences for glutamine, myo-inositol, leucine and trimethylamine. None of these molecules showed at P30 concentrations outside the P05 –P50 range.
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332
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Zhang S, Chen X, Yu J, Hong B, Lei Q, Fang W. Hydrophobic fractal surface from glycerol tripalmitate and the effects on C6 glioma cell growth. Colloids Surf B Biointerfaces 2016; 142:377-384. [PMID: 26970826 DOI: 10.1016/j.colsurfb.2016.03.011] [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] [Received: 10/09/2015] [Revised: 03/02/2016] [Accepted: 03/03/2016] [Indexed: 11/15/2022]
Abstract
To provide a biomimic environment for glial cell culture, glycerol tripalmitate (PPP) has been used as a raw material to prepare fractal surfaces with different degrees of hydrophobicity. The spontaneous formation of the hydrophobic fractal surfaces was monitored by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The surface morphologies were observed by a scanning electron microscope (SEM), and then the fractal dimension (FD) values of the surfaces were determined with the box-counting method. C6 glioma cells were cultured and compared on different hydrophobic PPP surfaces and poly-L-lysine (PLL)-coated surface. The cell numbers as a function of incubation time on different surfaces during the cell proliferation process were measured, and the cell morphologies were observed under a fluorescence microscope. Influences of hydrophobic fractal surfaces on the cell number and morphology were analyzed. The experimental results show that the cell proliferation rates decrease while the cell morphology complexities increase with the growth of the fractal dimensions of the PPP surfaces.
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Affiliation(s)
- Shanshan Zhang
- Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Xuerui Chen
- Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Jing Yu
- Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Biyuan Hong
- Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Qunfang Lei
- Department of Chemistry, Zhejiang University, Hangzhou 310027, China.
| | - Wenjun Fang
- Department of Chemistry, Zhejiang University, Hangzhou 310027, China.
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333
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Vandenhaute E, Drolez A, Sevin E, Gosselet F, Mysiorek C, Dehouck MP. Adapting coculture in vitro models of the blood-brain barrier for use in cancer research: maintaining an appropriate endothelial monolayer for the assessment of transendothelial migration. J Transl Med 2016; 96:588-98. [PMID: 26901835 DOI: 10.1038/labinvest.2016.35] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 01/06/2016] [Accepted: 01/14/2016] [Indexed: 12/14/2022] Open
Abstract
Although brain metastases are the most common brain tumors in adults, there are few treatment options in this setting. To colonize the brain, circulating tumor cells must cross the blood-brain barrier (BBB), which is situated within specialized, restrictive microvascular endothelium. Understanding how cancer cells manage to transmigrate through the BBB might enable this process to be prevented. In vitro models are dedicated tools for characterizing the cellular and molecular mechanisms that underlie transendothelial migration process, as long as they accurately mimic the brain endothelium's in vivo characteristics. The objective of the present study was to adapt an existing in vitro model of the human BBB for use in studying cancer cell transmigration. The model is based on the coculture of endothelial cells (ECs, derived from cord blood hematopoietic stem cells) and brain pericytes. To allow the migration of cancer cells into the lower compartment, our model had to be transposed onto inserts with a larger pore size. However, we encountered a problem when culturing ECs on large (3-μm)-pore inserts: the cells crossed the membrane and formed a non-physiological second layer on the lower face of the insert. Using 3-μm-pore inserts (in a 12-well plate format), we report here on a method that enables the maintenance of a single monolayer of ECs on the insert's upper face only. Under these chosen conditions, the ECs exhibited typical BBB properties found in the original model (including restricted paracellular permeability and the expression of continuous tight junctions). This modified in vitro model of the human BBB enabled us to investigate the migratory potential of the MDA-MB-231 cell line (derived from highly metastatic human breast cancer cells). Last, the results obtained were compared with the rate of transmigration through endothelia with no BBB features.
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Affiliation(s)
- Elodie Vandenhaute
- Laboratoire de la Barrière Hémato-Encéphalique-EA 2465, Faculté des Sciences Jean Perrin, Université d'Artois, LBHE, Lens, France
| | - Aurore Drolez
- Laboratoire de la Barrière Hémato-Encéphalique-EA 2465, Faculté des Sciences Jean Perrin, Université d'Artois, LBHE, Lens, France
| | - Emmanuel Sevin
- Laboratoire de la Barrière Hémato-Encéphalique-EA 2465, Faculté des Sciences Jean Perrin, Université d'Artois, LBHE, Lens, France
| | - Fabien Gosselet
- Laboratoire de la Barrière Hémato-Encéphalique-EA 2465, Faculté des Sciences Jean Perrin, Université d'Artois, LBHE, Lens, France
| | - Caroline Mysiorek
- Laboratoire de la Barrière Hémato-Encéphalique-EA 2465, Faculté des Sciences Jean Perrin, Université d'Artois, LBHE, Lens, France
| | - Marie-Pierre Dehouck
- Laboratoire de la Barrière Hémato-Encéphalique-EA 2465, Faculté des Sciences Jean Perrin, Université d'Artois, LBHE, Lens, France
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334
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Li S, Li Y, Chen G, Zhang J, Xu F, Wu M. Restraining reactive oxygen species in Listeria monocytogenes promotes the apoptosis of glial cells. Redox Rep 2016; 22:190-196. [PMID: 27120397 DOI: 10.1080/13510002.2016.1173327] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
OBJECTIVES Listeria monocytogenes is a facultative anaerobic foodborne pathogen that can traverse the blood-brain barrier and cause brain infection. L. monocytogenes infection induces host cell apoptosis in several cell types. In this study, we investigated the apoptosis of human glioma cell line U251 invaded by L. monocytogenes and evaluated the function of bacterial reactive oxygen species (ROS) during infection. METHODS Bacterial ROS level was reduced by carrying out treatment with N-acetyl cysteine (NAC) and diphenyleneiodonium chloride (DPI). After infection, the apoptosis of U251 cells was examined by flow cytometry assay and propidium iodide staining. RESULTS DPI and NAC efficiently decreased ROS level in L. monocytogenes without affecting bacterial growth. Moreover, the apoptosis of glial cells was enhanced upon invasion of DPI- and NAC-pretreated L. monocytogenes. DISCUSSION Results indicate that the apoptosis of glial cells can be induced by L. monocytogenes, and that the inhibition of bacterial ROS increases the apoptosis of host cells.
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Affiliation(s)
- Sen Li
- a School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology , 516 Jungong Road, Shanghai 200093 , China
| | - Yixuan Li
- a School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology , 516 Jungong Road, Shanghai 200093 , China
| | - Guowei Chen
- a School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology , 516 Jungong Road, Shanghai 200093 , China
| | - Jingchen Zhang
- b Certification and Review Center, Shanghai Municipal Food and Drug, Administration , Shanghai 200020 , China
| | - Fei Xu
- a School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology , 516 Jungong Road, Shanghai 200093 , China
| | - Man Wu
- a School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology , 516 Jungong Road, Shanghai 200093 , China
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335
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Ludwin SK, Rao VT, Moore CS, Antel JP. Astrocytes in multiple sclerosis. Mult Scler 2016; 22:1114-24. [PMID: 27207458 DOI: 10.1177/1352458516643396] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 03/09/2016] [Indexed: 01/13/2023]
Abstract
Recent experimental and clinical studies on astrocytes are unraveling the capabilities of these multi-functional cells in normal homeostasis, and in central nervous system (CNS) disease. This review focuses on understanding their behavior in all aspects of the initiation, evolution, and resolution of the multiple sclerosis (MS) lesion. Astrocytes display remarkable flexibility and variability of their physical structure and biochemical output, each aspect finely tuned to the specific stage and location of the disease, participating in both pathogenic and beneficial changes seen in acute and progressive forms. As examples, chemo-attractive or repulsive molecules may facilitate the entry of destructive immune cells but may also aid in the recruitment of oligodendrocyte precursors, essential for repair. Pro-inflammatory cytokines may attack pathogenic cells and also destroy normal oligodendrocytes, myelin, and axons. Protective trophic factors may also open the blood-brain barrier and modulate the extracellular matrix to favor recruitment and persistence of CNS-specific immune cells. A chronic glial scar may confer structural support following tissue loss and inhibit ingress of further noxious insults and also inhibit migration of reparative cells and molecules into the damaged tissue. Continual study into these processes offers the therapeutic opportunities to enhance the beneficial capabilities of these cells while limiting their destructive effects.
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Affiliation(s)
- Samuel K Ludwin
- Neuroimmunology, Montreal Neurological Institute, McGill University, Montreal, QC, Canada/Department of Pathology and Molecular Medicine, Queen's University, Kingston, ON, Canada
| | - Vijayaraghava Ts Rao
- Neuroimmunology, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Craig S Moore
- Division of BioMedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Jack P Antel
- Neuroimmunology, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
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336
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Reactive gliosis in the pathogenesis of CNS diseases. Biochim Biophys Acta Mol Basis Dis 2016; 1862:483-91. [DOI: 10.1016/j.bbadis.2015.11.014] [Citation(s) in RCA: 157] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Revised: 11/19/2015] [Accepted: 11/30/2015] [Indexed: 01/11/2023]
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337
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Glial-endothelial crosstalk regulates blood–brain barrier function. Curr Opin Pharmacol 2016; 26:39-46. [DOI: 10.1016/j.coph.2015.09.010] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Revised: 09/23/2015] [Accepted: 09/27/2015] [Indexed: 12/21/2022]
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338
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Worzfeld T, Schwaninger M. Apicobasal polarity of brain endothelial cells. J Cereb Blood Flow Metab 2016; 36:340-62. [PMID: 26661193 PMCID: PMC4759676 DOI: 10.1177/0271678x15608644] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 09/07/2015] [Indexed: 01/24/2023]
Abstract
Normal brain homeostasis depends on the integrity of the blood-brain barrier that controls the access of nutrients, humoral factors, and immune cells to the CNS. The blood-brain barrier is composed mainly of brain endothelial cells. Forming the interface between two compartments, they are highly polarized. Apical/luminal and basolateral/abluminal membranes differ in their lipid and (glyco-)protein composition, allowing brain endothelial cells to secrete or transport soluble factors in a polarized manner and to maintain blood flow. Here, we summarize the basic concepts of apicobasal cell polarity in brain endothelial cells. To address potential molecular mechanisms underlying apicobasal polarity in brain endothelial cells, we draw on investigations in epithelial cells and discuss how polarity may go awry in neurological diseases.
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Affiliation(s)
- Thomas Worzfeld
- Institute of Pharmacology, Biochemical-Pharmacological Center (BPC), University of Marburg, Marburg, Germany Department of Pharmacology, Max-Planck-Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Markus Schwaninger
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Lübeck, Germany German Research Centre for Cardiovascular Research, DZHK, Lübeck, Germany
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339
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Wilhelm I, Nyúl-Tóth Á, Suciu M, Hermenean A, Krizbai IA. Heterogeneity of the blood-brain barrier. Tissue Barriers 2016; 4:e1143544. [PMID: 27141424 DOI: 10.1080/21688370.2016.1143544] [Citation(s) in RCA: 150] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Revised: 01/08/2016] [Accepted: 01/12/2016] [Indexed: 01/08/2023] Open
Abstract
The brain microvascular network is comprised of capillaries, arterioles and venules, all of which retain - although to a different extent - blood-brain barrier (BBB) properties. Capillaries constitute the largest and tightest microvasculature. In contrast, venules have a looser junctional arrangement, while arterioles have a lower expression of P-gp. Development and maintenance of the BBB depends on the interaction of cerebral endothelial cells with pericytes and astrocytes, which are all heterogeneous in different regions of the central nervous system. At the level of circumventricular organs microvessels are permeable, containing fenestrations and discontinuous tight junctions. In addition, the blood-spinal cord barrier - where the number of pericytes is lower and expression of junctional proteins is reduced - is also more permeable than the BBB. However, much less is known about the cellular, molecular and functional differences among other regions of the brain. This review summarizes our current knowledge on the heterogeneity of the brain microvasculature.
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Affiliation(s)
- Imola Wilhelm
- Institute of Biophysics, Biological Research Centre, Hungarian Academy of Sciences ; Szeged, Hungary
| | - Ádám Nyúl-Tóth
- Institute of Biophysics, Biological Research Centre, Hungarian Academy of Sciences ; Szeged, Hungary
| | - Maria Suciu
- Institute of Life Sciences, Vasile Goldis Western University of Arad ; Arad, Romania
| | - Anca Hermenean
- Institute of Life Sciences, Vasile Goldis Western University of Arad ; Arad, Romania
| | - István A Krizbai
- Institute of Biophysics, Biological Research Centre, Hungarian Academy of Sciences; Szeged, Hungary; Institute of Life Sciences, Vasile Goldis Western University of Arad; Arad, Romania
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340
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Deracinois B, Lenfant AM, Dehouck MP, Flahaut C. Tissue Non-specific Alkaline Phosphatase (TNAP) in Vessels of the Brain. Subcell Biochem 2016. [PMID: 26219710 DOI: 10.1007/978-94-017-7197-9_7] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The microvessels of the brain represent around 3-4 % of the brain compartment but constitute the most important length (400 miles) and surface of exchange (20 m(2)) between the blood and the parenchyma of brain. Under influence of surrounding tissues, the brain microvessel endothelium expresses a specific phenotype that regulates and restricts the entry of compounds and cells from blood to brain, and defined the so-called blood-brain barrier (BBB). Evidences that alkaline phosphatase (AP) is a characteristic feature of the BBB phenotype that allows differentiating capillary endothelial cells from brain to those of the periphery have rapidly emerge. Thenceforth, AP has been rapidly used as a biomarker of the blood-brain barrier phenotype. In fact, brain capillary endothelial cells (BCECs) express exclusively tissue non-specific alkaline phosphatase (TNAP). There are several lines of evidence in favour of an important role for TNAP in brain function. TNAP is thought to be responsible for the control of transport of some compounds across the plasma membrane of the BCECs. Here, we report that levamisole-mediated inhibition of TNAP provokes an increase of the permeability to Lucifer Yellow of the endothelial monolayer. Moreover, we illustrate the disruption of the cytoskeleton organization. Interestingly, all observed effects were reversible 24 h after levamisole removal and correlated with the return of a full activity of the TNAP. This reversible effect remains to be studied in details to evaluate the potentiality of a levamisole treatment to enhance the entry of drugs in the brain parenchyma.
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341
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Michel L, Touil H, Pikor NB, Gommerman JL, Prat A, Bar-Or A. B Cells in the Multiple Sclerosis Central Nervous System: Trafficking and Contribution to CNS-Compartmentalized Inflammation. Front Immunol 2015; 6:636. [PMID: 26732544 PMCID: PMC4689808 DOI: 10.3389/fimmu.2015.00636] [Citation(s) in RCA: 101] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2015] [Accepted: 12/03/2015] [Indexed: 12/25/2022] Open
Abstract
Clinical trial results of peripheral B cell depletion indicate abnormal proinflammatory B cell properties, and particularly antibody-independent functions, contribute to relapsing MS disease activity. However, potential roles of B cells in progressive forms of disease continue to be debated. Prior work indicates that presence of B cells is fostered within the inflamed MS central nervous system (CNS) environment, and that B cell-rich immune cell collections may be present within the meninges of patients. A potential association is reported between such meningeal immune cell collections and the subpial pattern of cortical injury that is now considered important in progressive disease. Elucidating the characteristics of B cells that populate the MS CNS, how they traffic into the CNS and how they may contribute to progressive forms of the disease has become of considerable interest. Here, we will review characteristics of human B cells identified within distinct CNS subcompartments of patients with MS, including the cerebrospinal fluid, parenchymal lesions, and meninges, as well as the relationship between B cell populations identified in these subcompartments and the periphery. We will further describe the different barriers of the CNS and the possible mechanisms of migration of B cells across these barriers. Finally, we will consider the range of human B cell responses (including potential for antibody production, cytokine secretion, and antigen presentation) that may contribute to propagating inflammation and injury cascades thought to underlie MS progression.
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Affiliation(s)
- Laure Michel
- Département de Neurosciences, Centre de Recherche du Centre Hospitalier de l'Université de Montréal , Montréal, QC , Canada
| | - Hanane Touil
- Neuroimmunology Unit, Montreal Neurological Institute, McGill University , Montréal, QC , Canada
| | - Natalia B Pikor
- Department of Immunology, University of Toronto , Toronto, ON , Canada
| | | | - Alexandre Prat
- Département de Neurosciences, Centre de Recherche du Centre Hospitalier de l'Université de Montréal , Montréal, QC , Canada
| | - Amit Bar-Or
- Neuroimmunology Unit, Montreal Neurological Institute, McGill University, Montréal, QC, Canada; Experimental Therapeutics Program, Montreal Neurological Institute, McGill University, Montréal, QC, Canada
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342
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Li S, Chen G, Wu M, Zhang J, Wu S. Restraining of reactive oxygen species promotes invasion ofListeria monocytogenesinto glia cells. FEMS Microbiol Lett 2015; 363:fnv228. [DOI: 10.1093/femsle/fnv228] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/25/2015] [Indexed: 12/15/2022] Open
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343
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Waisman A, Liblau RS, Becher B. Innate and adaptive immune responses in the CNS. Lancet Neurol 2015; 14:945-55. [PMID: 26293566 DOI: 10.1016/s1474-4422(15)00141-6] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Revised: 04/22/2015] [Accepted: 06/11/2015] [Indexed: 12/11/2022]
Abstract
Almost every disorder of the CNS is said to have an inflammatory component, but the precise nature of inflammation in the CNS is often imprecisely defined, and the role of CNS-resident cells is uncertain compared with that of cells that invade the tissue from the systemic immune compartment. To understand inflammation in the CNS, the term must be better defined, and the response of tissue to disturbances in homoeostasis (eg, neurodegenerative processes) should be distinguished from disorders in which aberrant immune responses lead to CNS dysfunction and tissue destruction (eg, autoimmunity). Whether the inflammatory tissue response to injury is reparative or degenerative seems to be dependent on context and timing, as are the windows of opportunity for therapeutic intervention in inflammatory CNS diseases.
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Affiliation(s)
- Ari Waisman
- Institute for Molecular Medicine, University Medical Center of the Johannes Gutenberg University, Mainz, Germany.
| | - Roland S Liblau
- Centre de Physiopathologie Toulouse-Purpan, Université Toulouse 3, Toulouse, France
| | - Burkhard Becher
- Institute of Experimental Immunology, University of Zurich, Zurich, Switzerland
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344
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Rosenzweig S, Carmichael ST. The axon-glia unit in white matter stroke: mechanisms of damage and recovery. Brain Res 2015; 1623:123-34. [PMID: 25704204 PMCID: PMC4545468 DOI: 10.1016/j.brainres.2015.02.019] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2015] [Accepted: 02/10/2015] [Indexed: 01/07/2023]
Abstract
Approximately one quarter of all strokes in humans occur in white matter, and the progressive nature of white matter lesions often results in severe physical and mental disability. Unlike cortical grey matter stroke, the pathology of white matter stroke revolves around disrupted connectivity and injured axons and glial cells, rather than neuronal cell bodies. Consequently, the mechanisms behind ischemic damage to white matter elements, the regenerative responses of glial cells and their signaling pathways, all differ significantly from those in grey matter. Development of effective therapies for white matter stroke would require an enhanced understanding of the complex cellular and molecular interactions within the white matter, leading to the identification of new therapeutic targets. This review will address the unique properties of the axon-glia unit during white matter stroke, describe the challenging process of promoting effective white matter repair, and discuss recently-identified signaling pathways which may hold potential targets for repair in this disease. This article is part of a Special Issue entitled SI: Cell Interactions In Stroke.
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Affiliation(s)
- Shira Rosenzweig
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.
| | - S Thomas Carmichael
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.
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345
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Tajerian M, Clark JD. Novel cytogenic and neurovascular niches due to blood-brain barrier compromise in the chronic pain brain. Mol Pain 2015; 11:63. [PMID: 26453186 PMCID: PMC4600335 DOI: 10.1186/s12990-015-0066-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Accepted: 10/01/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The mechanisms by which painful injuries are linked to the multitude of pain-related comorbidities and neuroplastic changes in the brain remain poorly understood. Here we propose a model that relies on epi-neuronal communication through the vascular system to effect various brain structures. Specifically, we hypothesize that the differential vulnerability of the blood-brain barrier (BBB) in different brain regions is associated with region-specific neuroplastic and neurovascular changes that are in turn associated with particular pain-related comorbidities. PRESENTATION OF THE HYPOTHESIS We will present our hypothesis by focusing on two main points: (A) chronic pain (CP) is associated with differential BBB compromise. (B) Circulating mediators leaking through the BBB create cytogenic and neovascular niches associated with pain-related co-morbidities. TESTING THE HYPOTHESIS Pre-clinically, our hypothesis can be tested by observing, in parallel, BBB compromise, (neo)vascularization, neurogenesis, and their co-localization in animal pain models using imaging, microscopy, biochemical and other tools. Furthermore, the BBB can be experimentally damaged in specific brain regions, and the consequences of those lesions studied on nociception and associated comorbidities. Recently developed imaging techniques allow the analysis of blood brain barrier integrity in patients providing a route for translation of the laboratory findings. Though perhaps more limited, post-mortem examination of brains with available pain histories constitutes a second approach to addressing this hypothesis. IMPLICATIONS OF THE HYPOTHESIS Understanding changes in BBB permeability in chronic pain conditions has clear implications both for understanding the pathogenesis of chronic pain and for the design of novel treatments to prevent chronic pain and its consequences. More broadly, this hypothesis may help us to understand how peripheral injuries impact the brain via mechanisms other than commonly studied efferent sensory pathways.
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Affiliation(s)
- Maral Tajerian
- Veterans Affairs Palo Alto Health Care System, 3801 Miranda Ave., Palo Alto, CA, 94304, USA. .,Department of Anesthesiology, Stanford University School of Medicine, Stanford, CA, USA. .,Palo Alto Institute of Research and Education, Palo Alto, CA, USA.
| | - J David Clark
- Veterans Affairs Palo Alto Health Care System, 3801 Miranda Ave., Palo Alto, CA, 94304, USA. .,Department of Anesthesiology, Stanford University School of Medicine, Stanford, CA, USA. .,Palo Alto Institute of Research and Education, Palo Alto, CA, USA.
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346
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Ridder DA, Wenzel J, Müller K, Töllner K, Tong XK, Assmann JC, Stroobants S, Weber T, Niturad C, Fischer L, Lembrich B, Wolburg H, Grand'Maison M, Papadopoulos P, Korpos E, Truchetet F, Rades D, Sorokin LM, Schmidt-Supprian M, Bedell BJ, Pasparakis M, Balschun D, D'Hooge R, Löscher W, Hamel E, Schwaninger M. Brain endothelial TAK1 and NEMO safeguard the neurovascular unit. ACTA ACUST UNITED AC 2015; 212:1529-49. [PMID: 26347470 PMCID: PMC4577837 DOI: 10.1084/jem.20150165] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 08/07/2015] [Indexed: 12/25/2022]
Abstract
Ridder et al. show that deletion of NEMO, a component of NF-kB signaling, in brain endothelial cells results in increased cerebral vascular permeability and endothelial cell death, and recapitulates the neurological symptoms observed in the genetic disease incontinentia pigmenti. Inactivating mutations of the NF-κB essential modulator (NEMO), a key component of NF-κB signaling, cause the genetic disease incontinentia pigmenti (IP). This leads to severe neurological symptoms, but the mechanisms underlying brain involvement were unclear. Here, we show that selectively deleting Nemo or the upstream kinase Tak1 in brain endothelial cells resulted in death of endothelial cells, a rarefaction of brain microvessels, cerebral hypoperfusion, a disrupted blood–brain barrier (BBB), and epileptic seizures. TAK1 and NEMO protected the BBB by activating the transcription factor NF-κB and stabilizing the tight junction protein occludin. They also prevented brain endothelial cell death in a NF-κB–independent manner by reducing oxidative damage. Our data identify crucial functions of inflammatory TAK1–NEMO signaling in protecting the brain endothelium and maintaining normal brain function, thus explaining the neurological symptoms associated with IP.
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Affiliation(s)
- Dirk A Ridder
- Institute of Experimental and Clinical Pharmacology and Toxicology and Department of Radiation Oncology, University of Lübeck, 23562 Lübeck, Germany
| | - Jan Wenzel
- Institute of Experimental and Clinical Pharmacology and Toxicology and Department of Radiation Oncology, University of Lübeck, 23562 Lübeck, Germany German Research Centre for Cardiovascular Research (DZHK), Partner Site Hamburg/Lübeck/Kiel, 23562 Lübeck, Germany
| | - Kristin Müller
- Institute of Experimental and Clinical Pharmacology and Toxicology and Department of Radiation Oncology, University of Lübeck, 23562 Lübeck, Germany
| | - Kathrin Töllner
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, 30559 Hannover, Germany Center for Systems Neuroscience, 30559 Hannover, Germany
| | - Xin-Kang Tong
- Montreal Neurological Institute, McGill University, Montreal QC H3A 0G4, Canada
| | - Julian C Assmann
- Institute of Experimental and Clinical Pharmacology and Toxicology and Department of Radiation Oncology, University of Lübeck, 23562 Lübeck, Germany
| | - Stijn Stroobants
- Laboratory of Biological Psychology, KU Leuven, 3000 Leuven, Belgium
| | - Tobias Weber
- Institute of Experimental and Clinical Pharmacology and Toxicology and Department of Radiation Oncology, University of Lübeck, 23562 Lübeck, Germany
| | - Cristina Niturad
- Institute of Experimental and Clinical Pharmacology and Toxicology and Department of Radiation Oncology, University of Lübeck, 23562 Lübeck, Germany
| | - Lisanne Fischer
- Institute of Experimental and Clinical Pharmacology and Toxicology and Department of Radiation Oncology, University of Lübeck, 23562 Lübeck, Germany
| | - Beate Lembrich
- Institute of Experimental and Clinical Pharmacology and Toxicology and Department of Radiation Oncology, University of Lübeck, 23562 Lübeck, Germany
| | - Hartwig Wolburg
- Institute of Pathology and Neuropathology, University Hospital Tübingen, 72076 Tübingen, Germany
| | | | | | - Eva Korpos
- Institute of Physiological Chemistry and Pathobiochemistry, University of Münster, 48149 Münster, Germany
| | | | - Dirk Rades
- Institute of Experimental and Clinical Pharmacology and Toxicology and Department of Radiation Oncology, University of Lübeck, 23562 Lübeck, Germany
| | - Lydia M Sorokin
- Institute of Physiological Chemistry and Pathobiochemistry, University of Münster, 48149 Münster, Germany
| | - Marc Schmidt-Supprian
- Department of Hematology and Oncology, Klinikum rechts der Isar, Technische Universität München, 81675 Munich, Germany
| | - Barry J Bedell
- Montreal Neurological Institute, McGill University, Montreal QC H3A 0G4, Canada
| | | | - Detlef Balschun
- Laboratory of Biological Psychology, KU Leuven, 3000 Leuven, Belgium
| | - Rudi D'Hooge
- Laboratory of Biological Psychology, KU Leuven, 3000 Leuven, Belgium
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, 30559 Hannover, Germany Center for Systems Neuroscience, 30559 Hannover, Germany
| | - Edith Hamel
- Montreal Neurological Institute, McGill University, Montreal QC H3A 0G4, Canada
| | - Markus Schwaninger
- Institute of Experimental and Clinical Pharmacology and Toxicology and Department of Radiation Oncology, University of Lübeck, 23562 Lübeck, Germany German Research Centre for Cardiovascular Research (DZHK), Partner Site Hamburg/Lübeck/Kiel, 23562 Lübeck, Germany
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347
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Promising approaches to circumvent the blood-brain barrier: progress, pitfalls and clinical prospects in brain cancer. Ther Deliv 2015; 6:989-1016. [PMID: 26488496 DOI: 10.4155/tde.15.48] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Brain drug delivery is a major challenge for therapy of central nervous system (CNS) diseases. Biochemical modifications of drugs or drug nanocarriers, methods of local delivery, and blood-brain barrier (BBB) disruption with focused ultrasound and microbubbles are promising approaches which enhance transport or bypass the BBB. These approaches are discussed in the context of brain cancer as an example in CNS drug development. Targeting to receptors enabling transport across the BBB offers noninvasive delivery of small molecule and biological cancer therapeutics. Local delivery methods enable high dose delivery while avoiding systemic exposure. BBB disruption with focused ultrasound and microbubbles offers local and noninvasive treatment. Clinical trials show the prospects of these technologies and point to challenges for the future.
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348
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Healy LM, Michell-Robinson MA, Antel JP. Regulation of human glia by multiple sclerosis disease modifying therapies. Semin Immunopathol 2015; 37:639-49. [DOI: 10.1007/s00281-015-0514-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2015] [Accepted: 07/07/2015] [Indexed: 02/02/2023]
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349
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Broux B, Gowing E, Prat A. Glial regulation of the blood-brain barrier in health and disease. Semin Immunopathol 2015; 37:577-90. [PMID: 26245144 DOI: 10.1007/s00281-015-0516-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Accepted: 07/15/2015] [Indexed: 12/14/2022]
Abstract
The brain is the organ with the highest metabolic demand in the body. Therefore, it needs specialized vasculature to provide it with the necessary oxygen and nutrients, while protecting it against pathogens and toxins. The blood-brain barrier (BBB) is very tightly regulated by specialized endothelial cells, two basement membranes, and astrocytic endfeet. The proximity of astrocytes to the vessel makes them perfect candidates to influence the function of the BBB. Moreover, other glial cells are also known to contribute to either BBB quiescence or breakdown. In this review, we summarize the knowledge on glial regulation of the BBB during development, in homeostatic conditions in the adult, and during neuroinflammatory responses.
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Affiliation(s)
- Bieke Broux
- Neuroimmunology Unit, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), 900 Rue Saint Denis Street, Room R9.912, Montréal, Québec, Canada, H2X 0A9
- Department of Neuroscience, Faculté de Médecine, Université de Montréal, Montréal, Canada
- Hasselt University, Biomedical Research Institute and transnationale Universiteit Limburg, School of Life Sciences, Agoralaan, Building C, 3590, Diepenbeek, Belgium
| | - Elizabeth Gowing
- Neuroimmunology Unit, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), 900 Rue Saint Denis Street, Room R9.912, Montréal, Québec, Canada, H2X 0A9
- Department of Neuroscience, Faculté de Médecine, Université de Montréal, Montréal, Canada
| | - Alexandre Prat
- Neuroimmunology Unit, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), 900 Rue Saint Denis Street, Room R9.912, Montréal, Québec, Canada, H2X 0A9.
- Department of Neuroscience, Faculté de Médecine, Université de Montréal, Montréal, Canada.
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350
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Spampinato SF, Obermeier B, Cotleur A, Love A, Takeshita Y, Sano Y, Kanda T, Ransohoff RM. Sphingosine 1 Phosphate at the Blood Brain Barrier: Can the Modulation of S1P Receptor 1 Influence the Response of Endothelial Cells and Astrocytes to Inflammatory Stimuli? PLoS One 2015. [PMID: 26197437 PMCID: PMC4511229 DOI: 10.1371/journal.pone.0133392] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The ability of the Blood Brain Barrier (BBB) to maintain proper barrier functions, keeping an optimal environment for central nervous system (CNS) activity and regulating leukocytes’ access, can be affected in CNS diseases. Endothelial cells and astrocytes are the principal BBB cellular constituents and their interaction is essential to maintain its function. Both endothelial cells and astrocytes express the receptors for the bioactive sphingolipid S1P. Fingolimod, an immune modulatory drug whose structure is similar to S1P, has been approved for treatment in multiple sclerosis (MS): fingolimod reduces the rate of MS relapses by preventing leukocyte egress from the lymph nodes. Here, we examined the ability of S1P and fingolimod to act on the BBB, using an in vitro co-culture model that allowed us to investigate the effects of S1P on endothelial cells, astrocytes, and interactions between the two. Acting selectively on endothelial cells, S1P receptor signaling reduced cell death induced by inflammatory cytokines. When acting on astrocytes, fingolimod treatment induced the release of a factor, granulocyte macrophage colony-stimulating factor (GM-CSF) that reduced the effects of cytokines on endothelium. In an in vitro BBB model incorporating shear stress, S1P receptor modulation reduced leukocyte migration across the endothelial barrier, indicating a novel mechanism that might contribute to fingolimod efficacy in MS treatment.
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Affiliation(s)
- Simona F. Spampinato
- Neuroinflammation Research Center, Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Birgit Obermeier
- Neuroinflammation Research Center, Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Anne Cotleur
- Neuroinflammation Research Center, Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Anna Love
- Neuroinflammation Research Center, Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Yukio Takeshita
- Neuroinflammation Research Center, Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Yasuteru Sano
- Department of Neurology and Clinical Neuroscience, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan
| | - Takashi Kanda
- Department of Neurology and Clinical Neuroscience, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan
| | - Richard M. Ransohoff
- Neuroinflammation Research Center, Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
- * E-mail:
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