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Manu DR, Slevin M, Barcutean L, Forro T, Boghitoiu T, Balasa R. Astrocyte Involvement in Blood-Brain Barrier Function: A Critical Update Highlighting Novel, Complex, Neurovascular Interactions. Int J Mol Sci 2023; 24:17146. [PMID: 38138976 PMCID: PMC10743219 DOI: 10.3390/ijms242417146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 11/28/2023] [Accepted: 12/02/2023] [Indexed: 12/24/2023] Open
Abstract
Neurological disorders have been linked to a defective blood-brain barrier (BBB), with dysfunctions triggered by stage-specific disease mechanisms, some of these being generated through interactions in the neurovascular unit (NVU). Advanced knowledge of molecular and signaling mechanisms in the NVU and the emergence of improved experimental models allow BBB permeability prediction and the development of new brain-targeted therapies. As NVU constituents, astrocytes are the most numerous glial cells, characterized by a heterogeneity that occurs as a result of developmental and context-based gene expression profiles and the differential expression of non-coding ribonucleic acids (RNAs). Due to their heterogeneity and dynamic responses to different signals, astrocytes may have a beneficial or detrimental role in the BBB's barrier function, with deep effects on the pathophysiology of (and on the progression of) central nervous system diseases. The implication of astrocytic-derived extracellular vesicles in pathological mechanisms, due to their ability to pass the BBB, must also be considered. The molecular mechanisms of astrocytes' interaction with endothelial cells at the BBB level are considered promising therapeutic targets in different neurological conditions. Nevertheless, a personalized and well-founded approach must be addressed, due to the temporal and spatial heterogeneity of reactive astrogliosis states during disease.
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Affiliation(s)
- Doina Ramona Manu
- Centre for Advanced Medical and Pharmaceutical Research, “George Emil Palade” University of Medicine, Pharmacy, Science and Technology, 540142 Targu Mures, Romania; (D.R.M.); (M.S.)
| | - Mark Slevin
- Centre for Advanced Medical and Pharmaceutical Research, “George Emil Palade” University of Medicine, Pharmacy, Science and Technology, 540142 Targu Mures, Romania; (D.R.M.); (M.S.)
- Department of Life Sciences, Manchester Metropolitan University, Manchester M15 6BH, UK
| | - Laura Barcutean
- Neurology 1 Clinic, County Emergency Clinical Hospital, 540136 Targu Mures, Romania;
- Department of Neurology, “George Emil Palade” University of Medicine, Pharmacy, Science and Technology, 540142 Targu Mures, Romania
| | - Timea Forro
- Doctoral School, “George Emil Palade” University of Medicine, Pharmacy, Science and Technology, 540142 Targu Mures, Romania;
| | - Tudor Boghitoiu
- Psychiatry II Clinic, County Clinical Hospital, 540072 Targu Mures, Romania;
| | - Rodica Balasa
- Neurology 1 Clinic, County Emergency Clinical Hospital, 540136 Targu Mures, Romania;
- Department of Neurology, “George Emil Palade” University of Medicine, Pharmacy, Science and Technology, 540142 Targu Mures, Romania
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2
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Li C, Meng X, Wang L, Ren S, Matei N, Wu G. Mitigating the effects of Endothelin-1 following a minimally invasive surgery reduces the blood-brain barrier permeability in a rabbit model of intracerebral hemorrhage. BRAIN HEMORRHAGES 2022. [DOI: 10.1016/j.hest.2022.06.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
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3
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Sahebkar A, Sathyapalan T, Guest PC, Barreto GE. Identification of difluorinated curcumin molecular targets linked to traumatic brain injury pathophysiology. Biomed Pharmacother 2022; 148:112770. [PMID: 35278853 DOI: 10.1016/j.biopha.2022.112770] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 02/18/2022] [Accepted: 02/27/2022] [Indexed: 11/02/2022] Open
Abstract
Traumatic brain injury (TBI) affects approximately 50% of the world population at some point in their lifetime. To date, there are no effective treatments as most of the damage occurs due to secondary effects through a variety of pathophysiological pathways. The phytoceutical curcumin has been traditionally used as a natural remedy for numerous conditions including diabetes, inflammatory diseases, and neurological and neurodegenerative disorders. We have carried out a system pharmacology study to identify potential targets of a difluorinated curcumin analogue (CDF) that overlap with those involved in the pathophysiological mechanisms of TBI. This resulted in identification of 312 targets which are mostly involved in G protein-coupled receptor activity and cellular signalling. These include adrenergic, serotonergic, opioid and cannabinoid receptor families, which have been implicated in regulation of pain, inflammation, mood, learning and cognition pathways. We conclude that further studies should be performed to validate curcumin as a potential novel treatment to ameliorate the effects of TBI.
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Affiliation(s)
- Amirhossein Sahebkar
- Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran; Applied Biomedical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran; School of Medicine, The University of Western Australia, Perth, Australia; Department of Biotechnology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Thozhukat Sathyapalan
- Academic Diabetes, Endocrinology and Metabolism, Hull York Medical School, University of Hull, Hull, United Kingdom
| | - Paul C Guest
- Department of Biochemistry and Tissue Biology, University of Campinas (UNICAMP), Campinas, Brazil
| | - George E Barreto
- Department of Biological Sciences, University of Limerick, Limerick, Ireland.
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4
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Shen XY, Gao ZK, Han Y, Yuan M, Guo YS, Bi X. Activation and Role of Astrocytes in Ischemic Stroke. Front Cell Neurosci 2021; 15:755955. [PMID: 34867201 PMCID: PMC8635513 DOI: 10.3389/fncel.2021.755955] [Citation(s) in RCA: 66] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 10/22/2021] [Indexed: 12/21/2022] Open
Abstract
Ischemic stroke refers to the disorder of blood supply of local brain tissue caused by various reasons. It has high morbidity and mortality worldwide. Astrocytes are the most abundant glial cells in the central nervous system (CNS). They are responsible for the homeostasis, nutrition, and protection of the CNS and play an essential role in many nervous system diseases’ physiological and pathological processes. After stroke injury, astrocytes are activated and play a protective role through the heterogeneous and gradual changes of their gene expression, morphology, proliferation, and function, that is, reactive astrocytes. However, the position of reactive astrocytes has always been a controversial topic. Many studies have shown that reactive astrocytes are a double-edged sword with both beneficial and harmful effects. It is worth noting that their different spatial and temporal expression determines astrocytes’ various functions. Here, we comprehensively review the different roles and mechanisms of astrocytes after ischemic stroke. In addition, the intracellular mechanism of astrocyte activation has also been involved. More importantly, due to the complex cascade reaction and action mechanism after ischemic stroke, the role of astrocytes is still difficult to define. Still, there is no doubt that astrocytes are one of the critical factors mediating the deterioration or improvement of ischemic stroke.
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Affiliation(s)
- Xin-Ya Shen
- Graduate School of Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Zhen-Kun Gao
- Graduate School of Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Yu Han
- Department of Sport Rehabilitation, Shanghai University of Sport, Shanghai, China
| | - Mei Yuan
- Department of Sport Rehabilitation, Shanghai University of Sport, Shanghai, China
| | - Yi-Sha Guo
- Department of Sport Rehabilitation, Shanghai University of Sport, Shanghai, China
| | - Xia Bi
- Department of Rehabilitation Medicine, Shanghai University of Medicine and Health Sciences Affiliated Zhoupu Hospital, Shanghai, China
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5
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Targeting Endothelin in Alzheimer's Disease: A Promising Therapeutic Approach. BIOMED RESEARCH INTERNATIONAL 2021; 2021:7396580. [PMID: 34532504 PMCID: PMC8440097 DOI: 10.1155/2021/7396580] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 08/07/2021] [Indexed: 11/18/2022]
Abstract
Endothelin is a chemical mediator that helps in maintaining balance within the blood-brain barrier by regulating the levels of toxicants and molecules which pass through the brain, suggesting that a rise in its production determines Alzheimer's disease. The inequity in the amyloid β occurs due to a problem in its clearance from the brain initiating the production of reactive oxygen species and superoxide that activates a cascade wherein the release of inflammatory mediators and various enzymes like endothelin-converting enzymes take place. Furthermore, the cascade increases the levels of endothelin in the brain from endothelial cells. Endothelin levels are upregulated, which can be regulated by modulating the action of endothelin-converting enzymes and endothelin receptors. Hence, endothelin paves a pathway in the treatment of Alzheimer's disease. In this article, we have covered various mechanisms and preclinical studies that support and direct endothelin involvement in the progression of Alzheimer's disease by using various search tools such as PubMed, Science Direct, and Medline. Conclusive outcome data were extracted that all together defy contrivance pathways, potential drugs, endothelin receptors, and endothelin enzymes in our article giving profound importance to target endothelin for prevention and treatment of Alzheimer's disease.
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6
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Koyama Y, Tsuboi S, Mizogui F. Endothelin-1 decreases the expression of Ephrin-A and B subtypes in cultured rat astrocytes through ET B receptors. Neurosci Lett 2021; 741:135393. [PMID: 33279571 DOI: 10.1016/j.neulet.2020.135393] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 09/08/2020] [Accepted: 09/14/2020] [Indexed: 11/24/2022]
Abstract
Ephrin family proteins are cell surface molecules that regulate several cellular functions through cell-cell interactions. During nervous tissue repair after injury, the expression of ephrin subtypes in astrocytes is altered, affecting the axonal elongation and migration of neuronal precursors. However, the mechanism regulating the expression of ephrin subtypes in astrocytes has not been investigated. Herein, we studied the effects of endothelin-1 (ET-1) on the expression of ephrin subtypes in cultured rat astrocytes. Our results showed that ET-1 (100 nM) treatment for 1-24 h reduced the expression of ephrin-A2, -A4, -B2, and -B3 mRNA and protein in astrocytes, whereas the expression of ephrin-A1, -A3, -A5, and -B1 mRNA were not affected. Sarafotoxin S6c, a selective ETB receptor agonist, decreased the expression of ephrin-A2, -A4, -B2, and -B3 in cultured astrocytes. The decrease in ephrin-A2, -A4, -B2, and -B3 expression by ET-1 treatment was reduced in the presence of BQ788, an ETB receptor antagonist, while FR139317, an ETA receptor antagonist, had no effects. These results suggest that ET-1 is a signaling molecule that downregulates ephrin-A2, -A4, -B2, and -B3 expression in astrocytes.
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Affiliation(s)
- Yutaka Koyama
- Laboratory of Pharmacology, Kobe Pharmaceutical University, 4-19-1 Motoyama-Kita Higashinada, Kobe 668-8558 Japan.
| | - Sayaka Tsuboi
- Laboratory of Pharmacology, Kobe Pharmaceutical University, 4-19-1 Motoyama-Kita Higashinada, Kobe 668-8558 Japan
| | - Fuka Mizogui
- Laboratory of Pharmacology, Kobe Pharmaceutical University, 4-19-1 Motoyama-Kita Higashinada, Kobe 668-8558 Japan
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7
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Neurotransmitter Modulation of Carotid Body Germinal Niche. Int J Mol Sci 2020; 21:ijms21218231. [PMID: 33153142 PMCID: PMC7662800 DOI: 10.3390/ijms21218231] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 10/30/2020] [Accepted: 11/01/2020] [Indexed: 12/25/2022] Open
Abstract
The carotid body (CB), a neural-crest-derived organ and the main arterial chemoreceptor in mammals, is composed of clusters of cells called glomeruli. Each glomerulus contains neuron-like, O2-sensing glomus cells, which are innervated by sensory fibers of the petrosal ganglion and are located in close contact with a dense network of fenestrated capillaries. In response to hypoxia, glomus cells release transmitters to activate afferent fibers impinging on the respiratory and autonomic centers to induce hyperventilation and sympathetic activation. Glomus cells are embraced by interdigitating processes of sustentacular, glia-like, type II cells. The CB has an extraordinary structural plasticity, unusual for a neural tissue, as it can grow several folds its size in subjects exposed to sustained hypoxia (as for example in high altitude dwellers or in patients with cardiopulmonary diseases). CB growth in hypoxia is mainly due to the generation of new glomeruli and blood vessels. In recent years it has been shown that the adult CB contains a collection of quiescent multipotent stem cells, as well as immature progenitors committed to the neurogenic or the angiogenic lineages. Herein, we review the main properties of the different cell types in the CB germinal niche. We also summarize experimental data suggesting that O2-sensitive glomus cells are the master regulators of CB plasticity. Upon exposure to hypoxia, neurotransmitters and neuromodulators released by glomus cells act as paracrine signals that induce proliferation and differentiation of multipotent stem cells and progenitors, thus causing CB hypertrophy and an increased sensory output. Pharmacological modulation of glomus cell activity might constitute a useful clinical tool to fight pathologies associated with exaggerated sympathetic outflow due to CB overactivation.
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8
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Michinaga S, Inoue A, Yamamoto H, Ryu R, Inoue A, Mizuguchi H, Koyama Y. Endothelin receptor antagonists alleviate blood-brain barrier disruption and cerebral edema in a mouse model of traumatic brain injury: A comparison between bosentan and ambrisentan. Neuropharmacology 2020; 175:108182. [PMID: 32561219 DOI: 10.1016/j.neuropharm.2020.108182] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 05/29/2020] [Accepted: 06/05/2020] [Indexed: 12/14/2022]
Abstract
Traumatic brain injury (TBI) is induced by the immediate physical disruption of brain tissue. TBI causes disruption of the blood-brain barrier (BBB) and brain edema. In the cerebrospinal fluid (CSF) of TBI patients, endothelin-1 (ET-1) is increased, suggesting that ET-1 aggravates TBI-induced brain damage. In this study, the effect of bosentan (ETA/ETB antagonist) and ambrisentan (ETA antagonist) on BBB dysfunction and brain edema were examined in a mouse model of TBI using lateral fluid percussion injury (FPI). FPI to the mouse cerebrum increased the expression levels of ET-1 and ETB receptors. Administration of bosentan (3 or 15 mg/kg/day) and ambrisentan (0.1 or 0.5 mg/kg/day) at 6 and 24 h after FPI ameliorated BBB disruption and cerebral brain edema. Delayed administration of bosentan from 2 days after FPI also reduced BBB disruption and brain edema, while ambrisentan had no significant effects. FPI-induced expression levels of ET-1 and ETB receptors were reduced by bosentan, but not by ambrisentan. In cultured mouse astrocytes and brain microvessel endothelial cells, ET-1 (100 nM) increased prepro--ET-1 mRNA, which was inhibited by bosentan, but not by ambrisentan. FPI-induced alterations of the expression levels of matrix metalloproteinase-9, vascular endothelial growth factor-A, and angiopoietin-1 in the mouse cerebrum were reduced by delayed administration of bosentan, while ambrisentan had no significant effects. These results suggest that ET antagonists are effective in improving BBB disruption and cerebral edema in TBI patients and that an ETA/ETB non-selective type of antagonists is more effective.
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Affiliation(s)
- Shotaro Michinaga
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, 3-11-1 Nishikiori-Kita, Tondabayashi, Osaka, 584-8540, Japan
| | - Anna Inoue
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, 3-11-1 Nishikiori-Kita, Tondabayashi, Osaka, 584-8540, Japan
| | - Hayato Yamamoto
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, 3-11-1 Nishikiori-Kita, Tondabayashi, Osaka, 584-8540, Japan
| | - Ryotaro Ryu
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, 3-11-1 Nishikiori-Kita, Tondabayashi, Osaka, 584-8540, Japan
| | - Ayana Inoue
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, 3-11-1 Nishikiori-Kita, Tondabayashi, Osaka, 584-8540, Japan
| | - Hiroyuki Mizuguchi
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, 3-11-1 Nishikiori-Kita, Tondabayashi, Osaka, 584-8540, Japan
| | - Yutaka Koyama
- Laboratory of Pharmacology, Kobe Pharmaceutical University, 4-19-1 Motoyama-Kita Higashinada, Kobe, 668-8558, Japan.
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Michinaga S, Tanabe A, Nakaya R, Fukutome C, Inoue A, Iwane A, Minato Y, Tujiuchi Y, Miyake D, Mizuguchi H, Koyama Y. Angiopoietin-1/Tie-2 signal after focal traumatic brain injury is potentiated by BQ788, an ET B receptor antagonist, in the mouse cerebrum: Involvement in recovery of blood-brain barrier function. J Neurochem 2020; 154:330-348. [PMID: 31957020 DOI: 10.1111/jnc.14957] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 12/12/2019] [Accepted: 01/08/2020] [Indexed: 01/05/2023]
Abstract
Angiopoietin-1, an angiogenic factor, stabilizes brain microvessels through Tie-2 receptor tyrosine kinase. In traumatic brain injury, blood-brain barrier (BBB) disruption is an aggravating factor that induces brain edema and neuroinflammation. We previously showed that BQ788, an endothelin ETB receptor antagonist, promoted recovery of BBB function after lateral fluid percussion injury (FPI) in mice. To clarify the mechanisms underlying BBB recovery mediated by BQ788, we examined the involvements of the angiopoietin-1/Tie-2 signal. When angiopoietin-1 production and Tie-2 phosphorylation were assayed by quantitative reverse transcription polymerase chain reaction and western blotting, increased angiopoietin-1 production and Tie-2 phosphorylation were observed in 7-10 days after FPI in the mouse cerebrum, whereas no significant effects were obtained at 5 days. When BQ788 (15 nmol/day, i.c.v.) were administered in 2-5 days after FPI, increased angiopoietin-1 production and Tie-2 phosphorylation were observed. Immunohistochemical observations showed that brain microvessels and astrocytes contained angiopoietin-1 after FPI, and brain microvessels also contained phosphorylated Tie-2. Treatment with endothelin-1 (100 nM) decreased angiopoietin-1 production in cultured astrocytes and the effect was inhibited by BQ788 (1 μM). Five days after FPI, increased extravasation of Evans blue dye accompanied by reduction in claudin-5, occludin, and zonula occludens-1 proteins were observed in mouse cerebrum while these effects of FPI were reduced by BQ788 and exogenous angiopoietin-1 (1 μg/day, i.c.v.). The effects of BQ788 were inhibited by co-administration of a Tie-2 kinase inhibitor (40 nmol/day, i.c.v.). These results suggest that BQ788 administration after traumatic brain injury promotes recovery of BBB function through activation of the angiopoietin-1/Tie-2 signal.
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Affiliation(s)
- Shotaro Michinaga
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tondabayashi, Osaka, Japan
| | - Ayami Tanabe
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tondabayashi, Osaka, Japan
| | - Ryusei Nakaya
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tondabayashi, Osaka, Japan
| | - Chihiro Fukutome
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tondabayashi, Osaka, Japan
| | - Anna Inoue
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tondabayashi, Osaka, Japan
| | - Aya Iwane
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tondabayashi, Osaka, Japan
| | - Yukiko Minato
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tondabayashi, Osaka, Japan
| | - Yu Tujiuchi
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tondabayashi, Osaka, Japan
| | - Daisuke Miyake
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tondabayashi, Osaka, Japan
| | - Hiroyuki Mizuguchi
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tondabayashi, Osaka, Japan
| | - Yutaka Koyama
- Laboratory of Pharmacology, Kobe Pharmaceutical University, Kobe, Japan
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10
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Nagiri C, Shihoya W, Inoue A, Kadji FMN, Aoki J, Nureki O. Crystal structure of human endothelin ET B receptor in complex with peptide inverse agonist IRL2500. Commun Biol 2019; 2:236. [PMID: 31263780 PMCID: PMC6588608 DOI: 10.1038/s42003-019-0482-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Accepted: 05/21/2019] [Indexed: 01/01/2023] Open
Abstract
Endothelin receptors (ETA and ETB) are G-protein-coupled receptors activated by endothelin-1 and are involved in blood pressure regulation. IRL2500 is a peptide-mimetic of the C-terminal tripeptide of endothelin-1, and has been characterized as a potent ETB-selective antagonist, which has preventive effects against brain edema. Here, we report the crystal structure of the human ETB receptor in complex with IRL2500 at 2.7 Å-resolution. The structure revealed the different binding modes between IRL2500 and endothelin-1, and provides structural insights into its ETB-selectivity. Notably, the biphenyl group of IRL2500 penetrates into the transmembrane core proximal to D2.50, thus stabilizing the inactive conformation. Using the newly-established constitutively active mutant, we clearly demonstrate that IRL2500 functions as an inverse agonist for the ETB receptor. The current findings will expand the chemical space of ETR antagonists and facilitate the design of inverse agonists for other class A GPCRs.
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Affiliation(s)
- Chisae Nagiri
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033 Japan
| | - Wataru Shihoya
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033 Japan
| | - Asuka Inoue
- Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3, Aoba, Aramaki, Aoba-ku, Sendai, 980-8578 Miyagi Japan
| | - Francois Marie Ngako Kadji
- Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3, Aoba, Aramaki, Aoba-ku, Sendai, 980-8578 Miyagi Japan
| | - Junken Aoki
- Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3, Aoba, Aramaki, Aoba-ku, Sendai, 980-8578 Miyagi Japan
| | - Osamu Nureki
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033 Japan
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11
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Hoffman WH, Cudrici CD, Boodhoo D, Tatomir A, Rus V, Rus H. Intracerebral matrix metalloproteinase 9 in fatal diabetic ketoacidosis. Exp Mol Pathol 2019; 108:97-104. [PMID: 30986397 PMCID: PMC6563901 DOI: 10.1016/j.yexmp.2019.04.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 02/22/2019] [Accepted: 04/11/2019] [Indexed: 02/08/2023]
Abstract
There is increasing awareness that in addition to the metabolic crisis of diabetic ketoacidosis (DKA) caused by severe insulin deficiency, the immune inflammatory response is likely an active multicomponent participant in both the acute and chronic insults of this medical crisis, with strong evidence of activation for both the cytokine and complement system. Recent studies report that the matrix metalloproteinase enzymes and their inhibitors are systemically activated in young Type 1 diabetes mellitus (T1D) patients during DKA and speculate on their involvement in blood-brain barrier (BBB) disruption. Based on our previous studies, we address the question if matrix metalloproteinase 9 (MMP9) is expressed in the brain in the fatal brain edema (BE) of DKA. Our data show significant expression of MMP9 on the cells present in brain intravascular areas. The presence of MMP9 in intravascular cells and that of MMP+ cells seen passing the BBB indicates a possible role in tight junction protein disruption of the BBB, possibly leading to neurological complications including BE. We have also shown that MMP9 is expressed on neurons in the hippocampal areas of both BE/DKA cases investigated, while expression of tissue inhibitor of metalloproteinases 1 (TIMP1) was reduced in the same areas. We can speculate that intraneuronal MMP9 can be a sign of neurodegeneration. Further studies are necessary to determine the role of MMP9 in the pathogenesis of the neurologic catastrophe of the brain edema of DKA. Inhibition of MMP9 expression might be helpful in preserving neuronal function and BBB integrity during DKA.
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Affiliation(s)
- William H Hoffman
- Department of Pediatrics, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Cornelia D Cudrici
- Translational Vascular Medicine Branch, National Heart, Lung and Blood Institute, NIH, Bethesda, MD, USA
| | - Dallas Boodhoo
- Department of Neurology, University of Maryland, School of Medicine, Baltimore, MD, USA
| | - Alexandru Tatomir
- Department of Neurology, University of Maryland, School of Medicine, Baltimore, MD, USA
| | - Violeta Rus
- Department of Medicine, Division of Rheumatology and Clinical Immunology, University of Maryland, School of Medicine, Baltimore, MD, USA
| | - Horea Rus
- Department of Neurology, University of Maryland, School of Medicine, Baltimore, MD, USA.
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12
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Koyama Y, Sumie S, Nakano Y, Nagao T, Tokumaru S, Michinaga S. Endothelin-1 stimulates expression of cyclin D1 and S-phase kinase-associated protein 2 by activating the transcription factor STAT3 in cultured rat astrocytes. J Biol Chem 2019; 294:3920-3933. [PMID: 30670587 DOI: 10.1074/jbc.ra118.005614] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 01/17/2019] [Indexed: 01/04/2023] Open
Abstract
Brain injury-mediated induction of reactive astrocytes often leads to glial scar formation in damaged brain regions. Activation of signal transducer and activator of transcription 3 (STAT3), a member of the STAT family of transcription factors, plays a pivotal role in inducing reactive astrocytes and glial scar formation. Endothelin-1 (ET-1) is a vasoconstrictor peptide, and its levels increase in brain disorders and promote astrocytic proliferation through ETB receptors. To clarify the mechanisms underlying ET-1-mediated astrocytic proliferation, here we examined its effects on STAT3 in cultured rat astrocytes. ET-1 treatment stimulated Ser-727 phosphorylation of STAT3 in the astrocytes, but Tyr-705 phosphorylation was unaffected, and ET-induced STAT3 Ser-727 phosphorylation was reduced by the ETB antagonist BQ788. ET-1 stimulated STAT3 binding to its consensus DNA-binding motifs. Monitoring G1/S phase cell cycle transition through bromodeoxyuridine (BrdU) incorporation, we found that ET-1 increases BrdU incorporation into the astrocytic nucleus, indicating cell cycle progression. Of note, STAT3 chemical inhibition (with stattic or 5,15-diphenyl-porphine (5,15-DPP)) or siRNA-mediated STAT3 silencing reduced ET-induced BrdU incorporation. Moreover, ET-1 increased astrocytic expression levels of cyclin D1 and S-phase kinase-associated protein 2 (SKP2), which were reduced by stattic, 5,15-DPP, and STAT3 siRNA. ChIP-based PCR analysis revealed that ET-1 promotes the binding of SAT3 to the 5'-flanking regions of rat cyclin D1 and SKP2 genes. Our results suggest that STAT3-mediated regulation of cyclin D1 and SKP2 expression underlies ET-induced astrocytic proliferation.
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Affiliation(s)
- Yutaka Koyama
- From the Laboratory of Pharmacology, Kobe Pharmaceutical University, 4-19-1 Motoyamakita, Higashinada, Kobe, 658-8558, Japan and
| | - Satoshi Sumie
- the Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, 3-11-1 Nishikiori-Kita, Tonda-bayashi, Osaka 584-8540, Japan
| | - Yasutaka Nakano
- the Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, 3-11-1 Nishikiori-Kita, Tonda-bayashi, Osaka 584-8540, Japan
| | - Tomoya Nagao
- the Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, 3-11-1 Nishikiori-Kita, Tonda-bayashi, Osaka 584-8540, Japan
| | - Shiho Tokumaru
- the Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, 3-11-1 Nishikiori-Kita, Tonda-bayashi, Osaka 584-8540, Japan
| | - Shotaro Michinaga
- the Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, 3-11-1 Nishikiori-Kita, Tonda-bayashi, Osaka 584-8540, Japan
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13
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Michinaga S, Kimura A, Hatanaka S, Minami S, Asano A, Ikushima Y, Matsui S, Toriyama Y, Fujii M, Koyama Y. Delayed Administration of BQ788, an ET B Antagonist, after Experimental Traumatic Brain Injury Promotes Recovery of Blood-Brain Barrier Function and a Reduction of Cerebral Edema in Mice. J Neurotrauma 2018; 35:1481-1494. [PMID: 29316834 DOI: 10.1089/neu.2017.5421] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Traumatic brain injury (TBI) is induced by immediate physical disruption of brain tissue, and causes death and disability. Studies on experimental TBI animal models show that disruption of the blood-brain barrier (BBB) underlies brain edema and neuroinflammation during the delayed phase of TBI. In neurological disorders, endothelin-1 (ET-1) is involved in BBB dysfunction and brain edema. In this study, the effect of ET antagonists on BBB dysfunction and brain edema were examined in a mouse focal TBI model using lateral fluid percussion injury (FPI). ET-1 and ETB receptors were increased at 2-7 days after FPI, which was accompanied by extravasation of Evans blue (EB) and brain edema. Repeated intracerebroventricular administration of BQ788 (15 nmol/day), an ETB antagonist, from 2 days after FPI promoted recovery of EB extravasation and brain edema, while FR 139317, an ETA antagonist, had no effect. Delayed intravenous administration of BQ788 also promoted recovery from FPI-induced EB extravasation and brain edema. While FPI caused decreases in claudin-5, occludin, and zonula occludens-1 proteins, BQ788 reversed FPI-induced reductions of them. Immunohistochemical observation of the cerebrum after FPI showed that ETB receptors are predominantly expressed in glial fibrillary acidic protein (GFAP)-positive astrocytes. BQ788 reduced FPI-induced increases in GFAP-positive astrocytes. GFAP-positive astrocytes produced vascular endothelial growth factor-A (VEGF-A) and matrix metalloproteinase-9 (MMP9). FPI-induced increases in VEGF-A and MMP-9 production were reversed by BQ788. These results suggest that ETB receptor antagonism during the delayed phase of focal TBI promotes recovery of BBB function and reduction of brain edema.
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Affiliation(s)
- Shotaro Michinaga
- 1 Laboratory of Pharmacology, Osaka Ohtani University , Osaka, Japan
| | - Akimasa Kimura
- 1 Laboratory of Pharmacology, Osaka Ohtani University , Osaka, Japan
| | - Shunichi Hatanaka
- 1 Laboratory of Pharmacology, Osaka Ohtani University , Osaka, Japan
| | - Shizuho Minami
- 1 Laboratory of Pharmacology, Osaka Ohtani University , Osaka, Japan
| | - Arisa Asano
- 1 Laboratory of Pharmacology, Osaka Ohtani University , Osaka, Japan
| | - Yuki Ikushima
- 1 Laboratory of Pharmacology, Osaka Ohtani University , Osaka, Japan
| | - Shingo Matsui
- 1 Laboratory of Pharmacology, Osaka Ohtani University , Osaka, Japan
| | - Yoshiya Toriyama
- 1 Laboratory of Pharmacology, Osaka Ohtani University , Osaka, Japan
| | - Manami Fujii
- 1 Laboratory of Pharmacology, Osaka Ohtani University , Osaka, Japan
| | - Yutaka Koyama
- 2 Department of Pharmacology, Kobe Pharmaceutical University , Kobe, Japan
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14
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Cifuentes EG, Hornick MG, Havalad S, Donovan RL, Gulati A. Neuroprotective Effect of IRL-1620, an Endothelin B Receptor Agonist, on a Pediatric Rat Model of Middle Cerebral Artery Occlusion. Front Pediatr 2018; 6:310. [PMID: 30406063 PMCID: PMC6206019 DOI: 10.3389/fped.2018.00310] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 10/01/2018] [Indexed: 11/13/2022] Open
Abstract
Objective: The purpose of this study was to determine the potential neuroprotective effect of endothelin B (ETB) receptor agonist IRL-1620 treatment in a pediatric model of ischemic stroke. Design: A prospective, animal model study. Setting: An experimental laboratory. Subjects: Three-month-old male Wistar Han rats. Interventions: The rats underwent permanent middle cerebral artery occlusion (MCAO). At 2, 4, and 6 h post MCAO, they were treated with saline, IRL-1620 (5 μg/kg, IV), and/or ETB antagonist BQ788 (1 mg/kg, IV). Measurements and Main Results: The rats were evaluated over the course of 7 days for neurological and motor deficit, cerebral blood flow (CBF), and infarct volume. Young rats treated with IRL-1620 following MCAO improved significantly in neurological and motor assessments as compared to the vehicle-treated group, as measured by neurological score (P = 0.00188), grip test (P < 0.0001), and foot-fault error (P = 0.0075). CBF in the infarcted hemisphere decreased by 45-50% in all groups immediately following MCAO. After 7 days, CBF in the infarcted hemisphere of the IRL-1620 group increased significantly (P = 0.0007) when compared to the vehicle-treated group (+2.3 ± 23.3 vs. -45.4 ± 10.2%). Additionally, infarct volume was significantly reduced in IRL-1620-treated rats as compared to vehicle-treated rats (P = 0.0035, 41.4 ± 35.4 vs. 115.4 ± 40.9 mm3). Treatment with BQ788 blocked the effects of IRL-1620. Conclusions: IRL-1620 significantly reduced neurological and motor deficit as well as infarct volume while increasing CBF in a pediatric rat model of cerebral ischemia. These results indicate that selective ETB receptor stimulation may provide a novel therapeutic strategy in the treatment of pediatric ischemic stroke as has been demonstrated in adult ischemic stroke.
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Affiliation(s)
| | - Mary G Hornick
- Department of Pharmaceutical Sciences, Chicago College of Pharmacy, Midwestern University, Downers Grove, IL, United States
| | - Suresh Havalad
- Advocate Children's Hospital, Park Ridge, IL, United States
| | | | - Anil Gulati
- Department of Pharmaceutical Sciences, Chicago College of Pharmacy, Midwestern University, Downers Grove, IL, United States
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15
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Attenuation of opioid tolerance by ET B receptor agonist, IRL-1620, is independent of an accompanied decrease in nerve growth factor in mice. Heliyon 2017. [PMID: 28626808 PMCID: PMC5466593 DOI: 10.1016/j.heliyon.2017.e00317] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
AIM ETA receptor antagonists reverse opioid tolerance but the involvement of ETB receptors is unknown. In morphine or oxycodone tolerant mice we investigated (1) the effect of ETB receptor agonist, IRL-1620, on analgesic tolerance; (2) changes in expression of the brain ETA and ETB receptors; and (3) alterations in the brain VEGF, NGF, PI3K and notch-1 expression. MAIN METHODS Body weight, body temperature, and tail-flick latency were assessed before and after a challenge dose of morphine or oxycodone in vehicle or IRL-1620 treated mice. Expression studies were carried out using Western blots. KEY FINDINGS Tail flick latency to a challenge dose of opioid was significantly increased by IRL-1620 from 39% to 100% in morphine tolerant and from 8% to 83% in oxycodone tolerant mice. Morphine or oxycodone did not alter ETA or ETB receptor expression. IRL-1620 had no effect on ETA however it increased (61%) expression of ETB receptors. IRL-1620-induced increase in ETB receptor expression was attenuated by morphine (39.8%) and oxycodone (51.8%). VEGF expression was not affected by morphine or oxycodone and was unaltered by IRL-1620. However, NGF and PI3K expression was decreased (P < 0.001) by morphine and oxycodone and was unaffected by IRL-1620. Notch-1 expression was not altered by morphine, oxycodone or IRL-1620. SIGNIFICANCE ETB receptor agonist, IRL-1620, restored analgesic tolerance to morphine and oxycodone, but it did not affect morphine and oxycodone induced decrease in NGF/PI3K expression. It is concluded that IRL-1620 attenuates opioid tolerance without the involvement of NGF/PI3K pathway.
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16
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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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17
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Endothelin-1 Induces Degeneration of Cultured Motor Neurons Through a Mechanism Mediated by Nitric Oxide and PI3K/Akt Pathway. Neurotox Res 2017; 32:58-70. [PMID: 28285347 DOI: 10.1007/s12640-017-9711-3] [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: 06/30/2016] [Revised: 02/08/2017] [Accepted: 02/23/2017] [Indexed: 12/13/2022]
Abstract
Endothelin-1 (ET-1) is a vasoactive peptide produced by activated astrocytes and microglia and is implicated in initiating and sustaining reactive gliosis in neurodegenerative diseases. We have previously suggested that ET-1 can play a role in the pathophysiology of amyotrophic lateral sclerosis (ALS). Indeed, we reported that this peptide is abundantly expressed in reactive astrocytes in the spinal cord of SOD1-G93A mice and ALS patients and exerts a toxic effect on motor neurons (MNs) in an in vitro model of mixed spinal cord cultures enriched with reactive astrocytes. Here, we explored the possible mechanisms underlying the toxic effect of ET-1 on cultured MNs. We show that ET-1 toxicity is not directly caused by oxidative stress or activation of cyclooxygenase-2 but requires the synthesis of nitric oxide and is mediated by a reduced activation of the phosphoinositide 3-kinase pathway. Furthermore, we observed that ET-1 is also toxic for microglia, although its effect on MNs is independent of the presence of this type of glial cells. Our study confirms that ET-1 may contribute to MN death and corroborates the view that the modulation of ET-1 signaling might be a therapeutic strategy to slow down MN degeneration in ALS.
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18
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Gulati A. Endothelin Receptors, Mitochondria and Neurogenesis in Cerebral Ischemia. Curr Neuropharmacol 2017; 14:619-26. [PMID: 26786146 PMCID: PMC4981738 DOI: 10.2174/1570159x14666160119094959] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 09/11/2015] [Accepted: 12/29/2015] [Indexed: 12/22/2022] Open
Abstract
Background: Neurogenesis is most active during pre-natal development, however, it persists throughout the human lifespan. The putative role of mitochondria in neurogenesis and angiogenesis is gaining importance. Since, ETB receptor mediated neurogenesis and angiogenesis has been identified, the role of these receptors with relevance to mitochondrial functions is of interest. Methods: In addition to work from our laboratory, we undertook an extensive search of bibliographic databases for peer-reviewed research literature. Specific technical terms such as endothelin, mitochondria and neurogenesis were used to seek out and critically evaluate literature that was relevant. Results: The ET family consists of three isopeptides (ET-1, ET-2 and ET-3) that produce biological actions by acting on two types of receptors (ETA and ETB). In the central nervous system (CNS) ETA receptors are potent constrictors of the cerebral vasculature and appear to contribute in the causation of cerebral ischemia. ETA receptor antagonists have been found to be effective in animal model of cerebral ischemia; however, clinical studies have shown no efficacy. Mitochondrial functions are critically important for several neural development processes such as neurogenesis, axonal and dendritic growth, and synaptic formation. ET appears to impair mitochondrial functions through activation of ETA receptors. On the other hand, blocking ETB receptors has been shown to trigger apoptotic processes by activating intrinsic mitochondrial pathway. Mitochondria are important for their role in molecular regulation of neurogenesis and angiogenesis. Stimulation of ETB receptors in the adult ischemic brain has been found to promote angiogenesis and neurogenesis mediated through vascular endothelial growth factor and nerve growth factor. It will be interesting to investigate the effect of ETB receptor stimulation on mitochondrial functions in the CNS following cerebral ischemia. Conclusion: The findings of this review implicate brain ETB receptors in angiogenesis and neurogenesis following cerebral ischemia, it is possible that the positive effect of stimulating ETB receptors in cerebral ischemia may be mediated through mitochondrial functions.
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Affiliation(s)
- Anil Gulati
- Chicago College of Pharmacy, Midwestern University, Downers Grove, IL 60515-1235.
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19
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Yang P, Pavlovic D, Waldvogel H, Dragunow M, Synek B, Turner C, Faull R, Guan J. String Vessel Formation is Increased in the Brain of Parkinson Disease. JOURNAL OF PARKINSONS DISEASE 2016; 5:821-36. [PMID: 26444086 DOI: 10.3233/jpd-140454] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND String vessels are collapsed basement membrane without endothelium and have no function in circulation. String vessel formation contributes to vascular degeneration in Alzheimer disease. By comparing to age-matched control cases we have recently reported endothelial degeneration in brain capillaries of human Parkinson disease (PD). OBJECTIVE Current study evaluated changes of basement membrane of capillaries, string vessel formation and their association with astrocytes, blood-brain-barrier integrity and neuronal degeneration in PD. METHODS Brain tissue from human cases of PD and age-matched controls was used. Immunohistochemical staining for collagen IV, GFAP, NeuN, tyrosine hydroxylase, fibrinogen and Factor VIII was evaluated by image analysis in the substantia nigra, caudate nucleus and middle frontal gyrus. RESULTS While the basement-membrane-associated vessel density was similar between the two groups, the density of string vessels was significantly increased in the PD cases, particularly in the substantia nigra. Neuronal degeneration was found in all brain regions. Astrocytes and fibrinogen were increased in the caudate nuclei of PD cases compared with control cases. CONCLUSIONS Endothelial degeneration and preservation of basement membrane result in an increase of string vessel formation in PD. The data may suggest a possible role for cerebral hypoperfusion in the neuronal degeneration characteristic of PD, which needs further investigation. Elevated astrocytosis in the caudate nucleus of PD cases could be associated with disruption of the blood-brain barrier in this brain region.
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Affiliation(s)
- Panzao Yang
- Department of Pharmacology and Clinical Pharmacology, Faculty of Medical and Health Sciences, University of Auckland, New Zealand.,Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, New Zealand
| | - Darja Pavlovic
- Department of Pharmacology and Clinical Pharmacology, Faculty of Medical and Health Sciences, University of Auckland, New Zealand.,Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, New Zealand
| | - Henry Waldvogel
- Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, New Zealand.,Department of Anatomy with Radiology, Faculty of Medical and Health Sciences, University of Auckland, New Zealand
| | - Mike Dragunow
- Department of Pharmacology and Clinical Pharmacology, Faculty of Medical and Health Sciences, University of Auckland, New Zealand.,Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, New Zealand
| | - Beth Synek
- Department of Anatomical Pathology, LabPlus, Auckland City Hospital Auckland, New Zealand
| | - Clinton Turner
- Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, New Zealand.,Department of Anatomical Pathology, LabPlus, Auckland City Hospital Auckland, New Zealand
| | - Richard Faull
- Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, New Zealand.,Department of Anatomy with Radiology, Faculty of Medical and Health Sciences, University of Auckland, New Zealand
| | - Jian Guan
- Department of Pharmacology and Clinical Pharmacology, Faculty of Medical and Health Sciences, University of Auckland, New Zealand.,Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, New Zealand
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20
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The pathophysiological role of astrocytic endothelin-1. Prog Neurobiol 2016; 144:88-102. [DOI: 10.1016/j.pneurobio.2016.04.009] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 03/23/2016] [Accepted: 04/25/2016] [Indexed: 12/13/2022]
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21
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Michinaga S, Seno N, Fuka M, Yamamoto Y, Minami S, Kimura A, Hatanaka S, Nagase M, Matsuyama E, Yamanaka D, Koyama Y. Improvement of cold injury-induced mouse brain edema by endothelin ETBantagonists is accompanied by decreases in matrixmetalloproteinase 9 and vascular endothelial growth factor-A. Eur J Neurosci 2015; 42:2356-70. [DOI: 10.1111/ejn.13020] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Revised: 07/08/2015] [Accepted: 07/09/2015] [Indexed: 01/08/2023]
Affiliation(s)
- Shotaro Michinaga
- Laboratory of Pharmacology; Faculty of Pharmacy; Osaka Ohtani University; 3-11-1 Nishikiori-Kita, Tonda-bayashi Osaka 584-8540 Japan
| | - Naoki Seno
- Laboratory of Pharmacology; Faculty of Pharmacy; Osaka Ohtani University; 3-11-1 Nishikiori-Kita, Tonda-bayashi Osaka 584-8540 Japan
| | - Mayu Fuka
- Laboratory of Pharmacology; Faculty of Pharmacy; Osaka Ohtani University; 3-11-1 Nishikiori-Kita, Tonda-bayashi Osaka 584-8540 Japan
| | - Yui Yamamoto
- Laboratory of Pharmacology; Faculty of Pharmacy; Osaka Ohtani University; 3-11-1 Nishikiori-Kita, Tonda-bayashi Osaka 584-8540 Japan
| | - Shizuho Minami
- Laboratory of Pharmacology; Faculty of Pharmacy; Osaka Ohtani University; 3-11-1 Nishikiori-Kita, Tonda-bayashi Osaka 584-8540 Japan
| | - Akimasa Kimura
- Laboratory of Pharmacology; Faculty of Pharmacy; Osaka Ohtani University; 3-11-1 Nishikiori-Kita, Tonda-bayashi Osaka 584-8540 Japan
| | - Shunichi Hatanaka
- Laboratory of Pharmacology; Faculty of Pharmacy; Osaka Ohtani University; 3-11-1 Nishikiori-Kita, Tonda-bayashi Osaka 584-8540 Japan
| | - Marina Nagase
- Laboratory of Pharmacology; Faculty of Pharmacy; Osaka Ohtani University; 3-11-1 Nishikiori-Kita, Tonda-bayashi Osaka 584-8540 Japan
| | - Emi Matsuyama
- Laboratory of Pharmacology; Faculty of Pharmacy; Osaka Ohtani University; 3-11-1 Nishikiori-Kita, Tonda-bayashi Osaka 584-8540 Japan
| | - Daisuke Yamanaka
- Laboratory of Pharmacology; Faculty of Pharmacy; Osaka Ohtani University; 3-11-1 Nishikiori-Kita, Tonda-bayashi Osaka 584-8540 Japan
| | - Yutaka Koyama
- Laboratory of Pharmacology; Faculty of Pharmacy; Osaka Ohtani University; 3-11-1 Nishikiori-Kita, Tonda-bayashi Osaka 584-8540 Japan
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22
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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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23
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Koyama Y. Endothelin systems in the brain: involvement in pathophysiological responses of damaged nerve tissues. Biomol Concepts 2015; 4:335-47. [PMID: 25436584 DOI: 10.1515/bmc-2013-0004] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Accepted: 05/14/2013] [Indexed: 12/22/2022] Open
Abstract
In addition to their potent vasoconstriction effects, endothelins (ETs) show multiple actions in various tissues including the brain. The brain contains high levels of ETs, and their production is stimulated in many brain disorders. Accumulating evidence indicates that activation of brain ET receptors is involved in several pathophysiological responses in damaged brains. In this article, the roles of brain ET systems in relation to brain disorders are reviewed. In the acute phase of stroke, prolonged vasospasm of cerebral arteries and brain edema occur, both of which aggravate brain damage. Studies using ET antagonists show that activation of ETA receptors in the brain vascular smooth muscle induces vasospasm after stroke. Brain edema is induced by increased activity of vascular permeability factors, such as vascular endothelial growth factor and matrix metalloproteinases. Activation of ETB receptors stimulates astrocytic production of these permeability factors. Increases in reactive astrocytes are observed in neurodegenerative diseases and in the chronic phase of stroke, where they facilitate the repair of damaged nerve tissues by releasing neurotrophic factors. ETs promote the induction of reactive astrocytes through ETB receptors. ETs also stimulate the production of astrocytic neurotrophic factors. Recent studies have shown high expression of ETB receptors in neural progenitors. Activation of ETB receptors in neural progenitors promotes their proliferation and migration, suggesting roles for ETB receptors in neurogenesis. Much effort has been invested in the pursuit of novel drugs to induce protection or repair of damaged nerve tissues. From these studies, the pharmacological significance of brain ET systems as a possible target of neuroprotective drugs is anticipated.
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24
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Notch1-STAT3-ETBR signaling axis controls reactive astrocyte proliferation after brain injury. Proc Natl Acad Sci U S A 2015; 112:8726-31. [PMID: 26124113 DOI: 10.1073/pnas.1501029112] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Defining the signaling network that controls reactive astrogliosis may provide novel treatment targets for patients with diverse CNS injuries and pathologies. We report that the radial glial cell antigen RC2 identifies the majority of proliferating glial fibrillary acidic protein-positive (GFAP(+)) reactive astrocytes after stroke. These cells highly expressed endothelin receptor type B (ETB(R)) and Jagged1, a Notch1 receptor ligand. To study signaling in adult reactive astrocytes, we developed a model based on reactive astrocyte-derived neural stem cells isolated from GFAP-CreER-Notch1 conditional knockout (cKO) mice. By loss- and gain-of-function studies and promoter activity assays, we found that Jagged1/Notch1 signaling increased ETB(R) expression indirectly by raising the level of phosphorylated signal transducer and activator of transcription 3 (STAT3), a previously unidentified EDNRB transcriptional activator. Similar to inducible transgenic GFAP-CreER-Notch1-cKO mice, GFAP-CreER-ETB(R)-cKO mice exhibited a defect in reactive astrocyte proliferation after cerebral ischemia. Our results indicate that the Notch1-STAT3-ETB(R) axis connects a signaling network that promotes reactive astrocyte proliferation after brain injury.
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Signaling molecules regulating phenotypic conversions of astrocytes and glial scar formation in damaged nerve tissues. Neurochem Int 2014; 78:35-42. [DOI: 10.1016/j.neuint.2014.08.005] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Revised: 07/17/2014] [Accepted: 08/22/2014] [Indexed: 12/21/2022]
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Koyama Y, Michinaga S. [Roles of astroglia in the regulations of brain vascular permeability]. Nihon Yakurigaku Zasshi 2014; 144:115-119. [PMID: 25213611 DOI: 10.1254/fpj.144.115] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
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Overactivation of corticotropin-releasing factor receptor type 1 and aquaporin-4 by hypoxia induces cerebral edema. Proc Natl Acad Sci U S A 2014; 111:13199-204. [PMID: 25146699 DOI: 10.1073/pnas.1404493111] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Cerebral edema is a potentially life-threatening illness, but knowledge of its underlying mechanisms is limited. Here we report that hypobaric hypoxia induces rat cerebral edema and neuronal apoptosis and increases the expression of corticotrophin releasing factor (CRF), CRF receptor type 1 (CRFR1), aquaporin-4 (AQP4), and endothelin-1 (ET-1) in the cortex. These effects, except for the increased expression of CRF itself, could all be blocked by pretreatment with an antagonist of the CRF receptor CRFR1. We also show that, in cultured primary astrocytes: (i) both CRFR1 and AQP4 are expressed; (ii) exogenous CRF, acting through CRFR1, triggers signaling of cAMP/PKA, intracellular Ca(2+), and PKCε; and (iii) the up-regulated cAMP/PKA signaling contributes to the phosphorylation and expression of AQP4 to enhance water influx into astrocytes and produces an up-regulation of ET-1 expression. Finally, using CHO cells transfected with CRFR1(+) and AQP4(+), we show that transfected CRFR1(+) contributes to edema via transfected AQP4(+). In conclusion, hypoxia triggers cortical release of CRF, which acts on CRFR1 to trigger signaling of cAMP/PKA in cortical astrocytes, leading to activation of AQP4 and cerebral edema.
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Koyama Y, Hayashi M, Nagae R, Tokuyama S, Konishi T. Endothelin-1 increases the expression of VEGF-R1/Flt-1 receptors in rat cultured astrocytes through ETB receptors. J Neurochem 2014; 130:759-69. [PMID: 24862165 DOI: 10.1111/jnc.12770] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Revised: 05/22/2014] [Accepted: 05/23/2014] [Indexed: 01/04/2023]
Abstract
Expressions of vascular endothelial growth factor (VEGF) receptors in astrocytes are increased in damaged brains. To clarify the regulatory mechanisms of VEGF receptors, the effects of endothelin-1 (ET-1) were examined in rat cultured astrocytes. Expressions of VEGF-R1 and -R2 receptor mRNA were at similar levels, whereas the mRNA expressions of VEGF-R3 and Tie-2, a receptor for angiopoietins, were lower. Placenta growth factor, a selective agonist of the VEGF-R1 receptor, induced phosphorylation of focal adhesion kinase (FAK) and extracellular signal regulated kinase 1/2 (ERK1/2). Phosphorylations of FAK and ERK 1/2 were also stimulated by VEGF-E, a selective VEGF-R2 agonist. Increased phosphorylations of FAK and ERK1/2 by VEGF165 were reduced by selective antagonists for VEGF-R1 and -R2. Treatment with ET-1 increased VEGF-R1 mRNA and protein levels. The effects of ET-1 on VEGF-R1 mRNA were mimicked by Ala(1,3,11,15) -ET-1, a selective agonist for ETB receptors, and inhibited by BQ788, an ETB antagonist. ET-1 did not affect the mRNA levels of VEGF-R2, -R3, and Tie-2. Pre-treatment with ET-1 potentiated the effects of placenta growth factor on phosphorylations of FAK and ERK1/2. These findings suggest that ET-1 induces up-regulation of VEGF-R1 receptors in astrocytes, and potentiates VEGF signals in damaged nerve tissues. To clarify the regulatory mechanisms of vascular endothelial growth factor (VEGF) receptors, the effects of endothelin-1 (ET-1) were examined in rat cultured astrocytes. Effects of selective VEGF-R1 and R2 agonist showed that these receptors were linked to focal adhesion kinase (FAK) and extracellular signal regulated kinase 1/2 (ERK1/2). Treatment with ET-1 increased expression of VEGF-R1, which was mediated by ETB receptors. Pre-treatment with ET-1 potentiated the VEGF-R1-mediated activations of FAK and ERK1/2. These findings suggest that ET-1 induces up-regulation of VEGF-R1 receptors in astrocytes.
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Affiliation(s)
- Yutaka Koyama
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Osaka, Japan
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Michinaga S, Nagase M, Matsuyama E, Yamanaka D, Seno N, Fuka M, Yamamoto Y, Koyama Y. Amelioration of cold injury-induced cortical brain edema formation by selective endothelin ETB receptor antagonists in mice. PLoS One 2014; 9:e102009. [PMID: 25000290 PMCID: PMC4084986 DOI: 10.1371/journal.pone.0102009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 06/13/2014] [Indexed: 12/13/2022] Open
Abstract
Brain edema is a potentially fatal pathological condition that often occurs in stroke and head trauma. Following brain insults, endothelins (ETs) are increased and promote several pathophysiological responses. This study examined the effects of ETB antagonists on brain edema formation and disruption of the blood-brain barrier in a mouse cold injury model (Five- to six-week-old male ddY mice). Cold injury increased the water content of the injured cerebrum, and promoted extravasation of both Evans blue and endogenous albumin. In the injury area, expression of prepro-ET-1 mRNA and ET-1 peptide increased. Intracerebroventricular (ICV) administration of BQ788 (ETB antagonist), IRL-2500 (ETB antagonist), or FR139317 (ETA antagonist) prior to cold injury significantly attenuated the increase in brain water content. Bolus administration of BQ788, IRL-2500, or FR139317 also inhibited the cold injury-induced extravasation of Evans blue and albumin. Repeated administration of BQ788 and IRL-2500 beginning at 24 h after cold injury attenuated both the increase in brain water content and extravasation of markers. In contrast, FR139317 had no effect on edema formation when administrated after cold injury. Cold injury stimulated induction of glial fibrillary acidic protein-positive reactive astrocytes in the injured cerebrum. Induction of reactive astrocytes after cold injury was attenuated by ICV administration of BQ788 or IRL-2500. These results suggest that ETB receptor antagonists may be an effective approach to ameliorate brain edema formation following brain insults.
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Affiliation(s)
- Shotaro Michinaga
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tonda-bayashi, Osaka, Japan
| | - Marina Nagase
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tonda-bayashi, Osaka, Japan
| | - Emi Matsuyama
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tonda-bayashi, Osaka, Japan
| | - Daisuke Yamanaka
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tonda-bayashi, Osaka, Japan
| | - Naoki Seno
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tonda-bayashi, Osaka, Japan
| | - Mayu Fuka
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tonda-bayashi, Osaka, Japan
| | - Yui Yamamoto
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tonda-bayashi, Osaka, Japan
| | - Yutaka Koyama
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tonda-bayashi, Osaka, Japan
- * E-mail:
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Platero-Luengo A, González-Granero S, Durán R, Díaz-Castro B, Piruat JI, García-Verdugo JM, Pardal R, López-Barneo J. An O2-sensitive glomus cell-stem cell synapse induces carotid body growth in chronic hypoxia. Cell 2014; 156:291-303. [PMID: 24439383 DOI: 10.1016/j.cell.2013.12.013] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Revised: 10/07/2013] [Accepted: 11/11/2013] [Indexed: 01/28/2023]
Abstract
Neural stem cells (NSCs) exist in germinal centers of the adult brain and in the carotid body (CB), an oxygen-sensing organ that grows under chronic hypoxemia. How stem cell lineage differentiation into mature glomus cells is coupled with changes in physiological demand is poorly understood. Here, we show that hypoxia does not affect CB NSC proliferation directly. Rather, mature glomus cells expressing endothelin-1, the O2-sensing elements in the CB that secrete neurotransmitters in response to hypoxia, establish abundant synaptic-like contacts with stem cells, which express endothelin receptors, and instruct their growth. Inhibition of glomus cell transmitter release or their selective destruction markedly diminishes CB cell growth during hypoxia, showing that CB NSCs are under the direct "synaptic" control of the mature O2-sensitive cells. Thus, glomus cells not only acutely activate the respiratory center but also induce NSC-dependent CB hypertrophy necessary for acclimatization to chronic hypoxemia.
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Affiliation(s)
- Aida Platero-Luengo
- Departamento de Fisiología Médica y Biofísica, Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Seville, Spain
| | - Susana González-Granero
- Instituto Cavanilles de Biodiversidad y Biología Evolutiva, Universidad de Valencia, 46071 Valencia, Spain; Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
| | - Rocío Durán
- Departamento de Fisiología Médica y Biofísica, Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Seville, Spain
| | - Blanca Díaz-Castro
- Departamento de Fisiología Médica y Biofísica, Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Seville, Spain
| | - José I Piruat
- Departamento de Fisiología Médica y Biofísica, Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Seville, Spain
| | - José Manuel García-Verdugo
- Instituto Cavanilles de Biodiversidad y Biología Evolutiva, Universidad de Valencia, 46071 Valencia, Spain; Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
| | - Ricardo Pardal
- Departamento de Fisiología Médica y Biofísica, Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Seville, Spain.
| | - José López-Barneo
- Departamento de Fisiología Médica y Biofísica, Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Seville, Spain; Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain.
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Alvarez JI, Katayama T, Prat A. Glial influence on the blood brain barrier. Glia 2013; 61:1939-58. [PMID: 24123158 PMCID: PMC4068281 DOI: 10.1002/glia.22575] [Citation(s) in RCA: 380] [Impact Index Per Article: 34.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Revised: 08/13/2013] [Accepted: 08/19/2013] [Indexed: 12/14/2022]
Abstract
The Blood Brain Barrier (BBB) is a specialized vascular structure tightly regulating central nervous system (CNS) homeostasis. Endothelial cells are the central component of the BBB and control of their barrier phenotype resides on astrocytes and pericytes. Interactions between these cells and the endothelium promote and maintain many of the physiological and metabolic characteristics that are unique to the BBB. In this review we describe recent findings related to the involvement of astroglial cells, including radial glial cells, in the induction of barrier properties during embryogenesis and adulthood. In addition, we describe changes that occur in astrocytes and endothelial cells during injury and inflammation with a particular emphasis on alterations of the BBB phenotype. GLIA 2013;61:1939–1958
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Affiliation(s)
- Jorge Ivan Alvarez
- Neuroimmunology unit, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec, Canada
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Koyama Y, Kotani M, Sawamura T, Kuribayashi M, Konishi R, Michinaga S. Different actions of endothelin-1 on chemokine production in rat cultured astrocytes: reduction of CX3CL1/fractalkine and an increase in CCL2/MCP-1 and CXCL1/CINC-1. J Neuroinflammation 2013; 10:51. [PMID: 23627909 PMCID: PMC3675376 DOI: 10.1186/1742-2094-10-51] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Accepted: 04/02/2013] [Indexed: 01/03/2023] Open
Abstract
Background Chemokines are involved in many pathological responses of the brain.
Astrocytes produce various chemokines in brain disorders, but little is
known about the factors that regulate astrocytic chemokine production.
Endothelins (ETs) have been shown to regulate astrocytic functions through
ETB receptors. In this study, the effects of ETs on chemokine
production were examined in rat cerebral cultured astrocytes. Methods Astrocytes were prepared from the cerebra of one- to two-day-old Wistar rats
and cultured in serum-containing medium. After serum-starvation for 48
hours, astrocytes were treated with ETs. Total RNA was extracted using an
acid-phenol method and expression of chemokine mRNAs was determined by
quantitative RT-PCR. The release of chemokines was measured by ELISA. Results Treatment of cultured astrocytes with ET-1 and Ala1,3,11,15-ET-1,
an ETB agonist, increased mRNA levels of CCL2/MCP1 and
CXCL1/CINC-1. In contrast, CX3CL1/fractalkine mRNA expression decreased in
the presence of ET-1 and Ala1,3,11,15-ET-1. The effect of ET-1 on
chemokine mRNA expression was inhibited by BQ788, an ETB
antagonist. ET-1 increased CCL2 and CXCL1 release from cultured astrocytes,
but decreased that of CX3CL1. The increase in CCL2 and CXCL1 expression by
ET-1 was inhibited by actinomycin D, pyrrolidine dithiocarbamate, SN50,
mithramycin, SB203580 and SP600125. The decrease in CX3CL1 expression by
ET-1 was inhibited by cycloheximide, Ca2+ chelation and
staurosporine. Conclusion These findings suggest that ETs are one of the factors regulating astrocytic
chemokine production. Astrocyte-derived chemokines are involved in
pathophysiological responses of neurons and microglia. Therefore, the
ET-induced alterations of astrocytic chemokine production are of
pathophysiological significance in damaged brains.
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Affiliation(s)
- Yutaka Koyama
- Laboratory of Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, 3-11-1 Nishikiori-Kita, Tonda-bayashi, Osaka, 584-8540, Japan.
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Michinaga S, Ishida A, Takeuchi R, Koyama Y. Endothelin-1 stimulates cyclin D1 expression in rat cultured astrocytes via activation of Sp1. Neurochem Int 2013; 63:25-34. [PMID: 23619396 DOI: 10.1016/j.neuint.2013.04.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Revised: 03/25/2013] [Accepted: 04/08/2013] [Indexed: 11/16/2022]
Abstract
Endothelins (ETs), a family of vasoconstrictor peptides, are up-regulated in several pathological conditions in the brain, and induce astrocytic proliferation. We previously observed that ET-1 increased the expression of cyclin D1 protein. Thus, we confirmed the intracellular up-regulation of cyclin D1 by ET-1 in rat cultured astrocytes. Real-time PCR analysis indicated that ET-1 (100 nM) and Ala(1,3,11,15)-ET-1 (100 nM), a selective agonist of the ETB receptor, induced a time-dependent and transient increase in cyclin D1 mRNA. The effect of ET-1 was diminished by an ETB antagonist (1 μM BQ788) or inhibitors of Sp1 (500 nM mithramycin), ERK (50 μM PD98059), p38 (20 μM SB203580) and JNK (1 μM SP600125), but not inhibitors of NF-κB (10 μM SN50 and 100 μM pyrrolidine dithiocarbamate). The binding assay for Sp1 indicated that ET-1 increased the binding activity of Sp1 to consensus sequences, and two oligonucleotides of the cyclin D1 promoter including the Sp1-binding sites diminished the effect of ET-1. Western blot analysis showed that ET-1 induced time-dependent and transient phosphorylation of Sp1 on Thr453 and Thr739 via the ETB receptor. ET-1-induced phosphorylation of Sp1 was attenuated by PD98059 and SP600125. Additionally, ET-1 increased the incorporation of bromodeoxyuridine (BrdU) in cultured astrocytes and the number of BrdU-positive cells decreased in the presence of PD98059, SP600125 and mithramycin. These results suggest that ET-1 increases the expression of cyclin D1 via activation of Sp1 and induces astrocytic proliferation.
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Affiliation(s)
- Shotaro Michinaga
- Faculty of Pharmacy, Laboratory of Pharmacology, Osaka Ohtani University, 3-11-1 Nishikiori-Kita, Tonda-bayashi, Osaka 584-8540, Japan
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Koyama Y, Maebara Y, Hayashi M, Nagae R, Tokuyama S, Michinaga S. Endothelins reciprocally regulate VEGF-A and angiopoietin-1 production in cultured rat astrocytes: implications on astrocytic proliferation. Glia 2012; 60:1954-63. [PMID: 22927341 DOI: 10.1002/glia.22411] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2012] [Revised: 07/11/2012] [Accepted: 07/31/2012] [Indexed: 11/07/2022]
Abstract
Vascular endothelial growth factors (VEGFs) and angiopoietins (ANGs) are involved in pathophysiological responses in damaged nerve tissues. Astrocytes produce VEGFs and ANGs upon brain ischemia and traumatic injury. To clarify the extracellular signals regulating VEGF and ANG production, effects of endothelins (ETs), a family of endothelium-derived peptides, were examined in cultured rat astrocytes. ET-1 (100 nM) and Ala(1,3,11,15)-ET-1 (100 nM), an ET(B) receptor agonist, increased VEGF-A mRNA levels in cultured astrocytes, while ANG-1 mRNA was decreased by ETs. ET-1 did not affect astrocytic VEGF-B, placental growth factor (PLGF), and ANG-2 mRNA levels. The effects of ET-1 on VEGF-A and ANG-1 mRNAs were inhibited by BQ788, an ET(B) antagonist. Release of VEGF-A proteins from cultured astrocytes was increased by ET-1. In contrast, ET-1 reduced release of astrocytic ANG-1. Exogenous ET-1 (100 nM) and VEGF(165) (100 ng/mL), an isopeptide of VEGF-A, stimulated bromodeoxyuridine (BrdU) incorporation into cultured astrocytes. Treatment with ET-1 and VEGF(165) increased the numbers of cyclin D1-positive astrocytes. Exogenous ANG-1 (250 ng/mL) did not stimulate the BrdU incorporation. Increases in BrdU incorporation by ET-1 and VEGF(165) were not affected by ANG-1. In 60-70% confluent cultures, SU4312 (10 μM), a VEGF receptor tyrosine kinase inhibitor, partially reduced the effects of ET-1 on BrdU incorporation and cyclin D1 expression. ET-induced BrdU incorporation and cyclin D1 expression were reduced by a neutralizing antibody against VEGF-A. Our findings suggest that ET-1 is a factor regulating astrocytic VEGF-A and ANG-1, and that increased VEGF-A production potentiates ET-induced astrocytic proliferation by an autocrine mechanism.
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Affiliation(s)
- Yutaka Koyama
- Faculty of Pharmacy, Laboratory of Pharmacology, Osaka Ohtani University, 3-11-1 Nishikiori-Kita, Tonda-bayashi, Osaka, Japan.
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Choudhury ME, Sugimoto K, Kubo M, Iwaki H, Tsujii T, Kyaw WT, Nishikawa N, Nagai M, Tanaka J, Nomoto M. Zonisamide up-regulated the mRNAs encoding astrocytic anti-oxidative and neurotrophic factors. Eur J Pharmacol 2012; 689:72-80. [PMID: 22659113 DOI: 10.1016/j.ejphar.2012.05.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Revised: 04/27/2012] [Accepted: 05/15/2012] [Indexed: 01/28/2023]
Abstract
Zonisamide has been proven as an effective drug for the recovery of degenerating dopaminergic neurons in the animal models of Parkinson's disease. However, several lines of evidence have questioned the neuroprotective capacity of zonisamide in animal models of Parkinson's disease. Although it suppresses dopaminergic neurodegeneration in animal models, the cellular and molecular mechanisms underlying the effectiveness of zonisamide are not fully understood. The current study demonstrates the effects of zonisamide on astrocyte cultures and two 6-hydroxydopamine-induced models of Parkinson's disease. Using primary astrocyte cultures, we showed that zonisamide up-regulated the expression of mRNA encoding mesencephalic astrocyte-derived neurotrophic factor, vascular endothelial growth factor, proliferating cell nuclear antigen, metallothionein-2, copper/zinc superoxide dismutase, and manganese superoxide dismutase. Similar responses to zonisamide were found in substantia nigra where the rats were pre-treated with 6-hydroxydopamine. Notably, pharmacological inhibition of 6-hydroxydopamine-induced toxicity by zonisamide pre-treatment was also confirmed using rat mesencephalic organotypic slice cultures of substantia nigra. In addition to this, zonisamide post-treatment also attenuated the nigral tyrosine hydroxylase-positive neuronal loss induced by 6-hydroxydopamine. Taken together, these studies demonstrate that zonisamide protected dopamine neurons in two Parkinson's disease models through a novel mechanism, namely increasing the expression of some important astrocyte-mediated neurotrophic and anti-oxidative factors.
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Affiliation(s)
- M E Choudhury
- Department of Therapeutic Medicine (Clinical Pharmacology and Neurology), Ehime University Graduate School of Medicine, Shitsukawa, Toon-Shi, Ehime 791-0295, Japan
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