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Prado-Fernández MF, Magdaleno-Madrigal VM, Cabañas-García E, Mucio-Ramírez S, Almazán-Alvarado S, Pérez-Molphe-Balch E, Gómez-Aguirre YA, Sánchez-Jaramillo E. Pereskia sacharosa Griseb. (Cactaceae) Prevents Lipopolysaccharide-Induced Neuroinflammation in Rodents via Down-Regulating TLR4/CD14 Pathway and GABAA γ2 Activity. Curr Issues Mol Biol 2024; 46:6885-6902. [PMID: 39057053 PMCID: PMC11275307 DOI: 10.3390/cimb46070411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2024] [Revised: 06/05/2024] [Accepted: 06/06/2024] [Indexed: 07/28/2024] Open
Abstract
Pereskia sacharosa Griseb. is a plant used in traditional herbal medicine to treat inflammation. We analyzed the phenolic content of P. sacharosa leaves (EEPs) by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and investigated the anti-inflammatory properties of EEPs and its flavonoid fraction (F10) in animal models subjected to acute neuroinflammation induced by bacterial lipopolysaccharide (LPS). Coronal brain sections of C57BL/6JN male mice or Wistar male rats administered with EEPs or F10 before LPS were subjected to in situ hybridization to determine c-fos and CD14 mRNA levels in the hypothalamus or GABAA γ2 mRNA levels in the hippocampus. Theta oscillations were recorded every 6 h in the hippocampus of Wistar rats. In total, five flavonoids and eight phenolic acids were identified and quantified in P. sacharosa leaves. Either EEPs or F10 crossed the blood-brain barrier (BBB) into the brain and reduced the mRNA expression of c-fos, CD14, and GABAA γ2. A decrease in theta oscillation was observed in the hippocampus of the LPS group, while the F10 + LPS group overrode the LPS effect on theta activity. We conclude that the bioactive compounds of P. sacharosa reduce the central response to inflammation, allowing the early return of ambulatory activity and well-being of the animal.
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Affiliation(s)
- María Fernanda Prado-Fernández
- Departamento de Química, Centro de Ciencias Básicas, Universidad Autónoma de Aguascalientes, Av. Universidad 940, Ciudad Universitaria, Aguascalientes 20131, Aguascalientes, Mexico; (M.F.P.-F.); (E.P.-M.-B.)
| | - Víctor Manuel Magdaleno-Madrigal
- Laboratorio de Neuromodulación Experimental, Dirección de Investigaciones en Neurociencias, Instituto Nacional de Psiquiatría Ramón de la Fuente Muñiz, Calz. México Xochimilco No. 101, Col. San Lorenzo Huipulco, Ciudad de México 14370, Mexico;
| | - Emmanuel Cabañas-García
- Centro de Estudios Científicos y Tecnológicos No. 18, Instituto Politécnico Nacional, Blvd. del Bote 202 Cerro del Gato Ejido La Escondida, Col. Ciudad Administrativa, Zacatecas 98160, Zacatecas, Mexico;
| | - Samuel Mucio-Ramírez
- Departamento de Neuromorfología Funcional, Dirección de Investigaciones en Neurociencias, Instituto Nacional de Psiquiatría Ramón de la Fuente Muñiz, Calz. México Xochimilco No. 101, Col. San Lorenzo Huipulco, Ciudad de México 14370, Mexico;
| | - Salvador Almazán-Alvarado
- Laboratorio de Neurofisiología del Control y la Regulación, Dirección de Investigaciones en Neurociencias, Instituto Nacional de Psiquiatría Ramón de la Fuente Muñiz, Calz. México Xochimilco No. 101, Col. San Lorenzo Huipulco, Ciudad de México 14370, Mexico;
| | - Eugenio Pérez-Molphe-Balch
- Departamento de Química, Centro de Ciencias Básicas, Universidad Autónoma de Aguascalientes, Av. Universidad 940, Ciudad Universitaria, Aguascalientes 20131, Aguascalientes, Mexico; (M.F.P.-F.); (E.P.-M.-B.)
| | - Yenny Adriana Gómez-Aguirre
- Departamento de Química, Centro de Ciencias Básicas, Universidad Autónoma de Aguascalientes, Av. Universidad 940, Ciudad Universitaria, Aguascalientes 20131, Aguascalientes, Mexico; (M.F.P.-F.); (E.P.-M.-B.)
- CONAHCyT Research Fellow, Universidad Autónoma de Aguascalientes, Av. Universidad 940, Ciudad Universitaria, Aguascalientes 20131, Aguascalientes, Mexico
| | - Edith Sánchez-Jaramillo
- Laboratorio de Neuroendocrinología Molecular, Dirección de Investigaciones en Neurociencias, Instituto Nacional de Psiquiatría Ramón de la Fuente Muñiz, Calz. México-Xochimilco 101, Col. San Lorenzo, Huipulco, Ciudad de México 14370, Mexico
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Weber CM, Moiz B, Clyne AM. Brain microvascular endothelial cell metabolism and its ties to barrier function. VITAMINS AND HORMONES 2024; 126:25-75. [PMID: 39029976 DOI: 10.1016/bs.vh.2024.05.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/21/2024]
Abstract
Brain microvascular endothelial cells, which lie at the interface between blood and brain, are critical to brain energetics. These cells must precisely balance metabolizing nutrients for their own demands with transporting nutrients into the brain to sustain parenchymal cells. It is essential to understand this integrated metabolism and transport so that we can develop better diagnostics and therapeutics for neurodegenerative diseases such as Alzheimer's disease, multiple sclerosis, and traumatic brain injury. In this chapter, we first describe brain microvascular endothelial cell metabolism and how these cells regulate both blood flow and nutrient transport. We then explain the impact of brain microvascular endothelial cell metabolism on the integrity of the blood-brain barrier, as well as how metabolites produced by the endothelial cells impact other brain cells. We detail some ways that cell metabolism is typically measured experimentally and modeled computationally. Finally, we describe changes in brain microvascular endothelial cell metabolism in aging and neurodegenerative diseases. At the end of the chapter, we highlight areas for future research in brain microvascular endothelial cell metabolism. The goal of this chapter is to underscore the importance of nutrient metabolism and transport at the brain endothelium for cerebral health and neurovascular disease treatment.
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Affiliation(s)
- Callie M Weber
- Fischell Department of Bioengineering, University of Maryland, College Park, MD, United States
| | - Bilal Moiz
- Fischell Department of Bioengineering, University of Maryland, College Park, MD, United States
| | - Alisa Morss Clyne
- Fischell Department of Bioengineering, University of Maryland, College Park, MD, United States.
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Carnwath TP, Demel SL, Prestigiacomo CJ. Genetics of ischemic stroke functional outcome. J Neurol 2024; 271:2345-2369. [PMID: 38502340 PMCID: PMC11055934 DOI: 10.1007/s00415-024-12263-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 02/14/2024] [Accepted: 02/15/2024] [Indexed: 03/21/2024]
Abstract
Ischemic stroke, which accounts for 87% of cerebrovascular accidents, is responsible for massive global burden both in terms of economic cost and personal hardship. Many stroke survivors face long-term disability-a phenotype associated with an increasing number of genetic variants. While clinical variables such as stroke severity greatly impact recovery, genetic polymorphisms linked to functional outcome may offer physicians a unique opportunity to deliver personalized care based on their patient's genetic makeup, leading to improved outcomes. A comprehensive catalogue of the variants at play is required for such an approach. In this review, we compile and describe the polymorphisms associated with outcome scores such as modified Rankin Scale and Barthel Index. Our search identified 74 known genetic polymorphisms spread across 48 features associated with various poststroke disability metrics. The known variants span diverse biological systems and are related to inflammation, vascular homeostasis, growth factors, metabolism, the p53 regulatory pathway, and mitochondrial variation. Understanding how these variants influence functional outcome may be helpful in maximizing poststroke recovery.
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Affiliation(s)
- Troy P Carnwath
- University of Cincinnati College of Medicine, Cincinnati, OH, 45267, USA.
| | - Stacie L Demel
- Department of Neurology, University of Cincinnati College of Medicine, Cincinnati, OH, 45267, USA
| | - Charles J Prestigiacomo
- Department of Neurosurgery, University of Cincinnati College of Medicine, Cincinnati, OH, 45267, USA
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Thyroid Hormone Transporters MCT8 and OATP1C1 Are Expressed in Pyramidal Neurons and Interneurons in the Adult Motor Cortex of Human and Macaque Brain. Int J Mol Sci 2023; 24:ijms24043207. [PMID: 36834621 PMCID: PMC9965431 DOI: 10.3390/ijms24043207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 01/26/2023] [Accepted: 02/01/2023] [Indexed: 02/09/2023] Open
Abstract
Monocarboxylate transporter 8 (MCT8) and organic anion transporter polypeptide 1C1 (OATP1C1) are thyroid hormone (TH) transmembrane transporters that play an important role in the availability of TH for neural cells, allowing their proper development and function. It is important to define which cortical cellular subpopulations express those transporters to explain why MCT8 and OATP1C1 deficiency in humans leads to dramatic alterations in the motor system. By means of immunohistochemistry and double/multiple labeling immunofluorescence in adult human and monkey motor cortices, we demonstrate the presence of both transporters in long-projection pyramidal neurons and in several types of short-projection GABAergic interneurons in both species, suggesting a critical position of these transporters for modulating the efferent motor system. MCT8 is present at the neurovascular unit, but OATP1C1 is only present in some of the large vessels. Both transporters are expressed in astrocytes. OATP1C1 was unexpectedly found, only in the human motor cortex, inside the Corpora amylacea complexes, aggregates linked to substance evacuation towards the subpial system. On the basis of our findings, we propose an etiopathogenic model that emphasizes these transporters' role in controlling excitatory/inhibitory motor cortex circuits in order to understand some of the severe motor disturbances observed in TH transporter deficiency syndromes.
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Puris E, Saveleva L, de Sousa Maciel I, Kanninen KM, Auriola S, Fricker G. Protein Expression of Amino Acid Transporters Is Altered in Isolated Cerebral Microvessels of 5xFAD Mouse Model of Alzheimer's Disease. Mol Neurobiol 2023; 60:732-748. [PMID: 36367657 PMCID: PMC9849299 DOI: 10.1007/s12035-022-03111-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 10/26/2022] [Indexed: 11/13/2022]
Abstract
Membrane transporters such as ATP-binding cassette (ABC) and solute carrier (SLC) transporters expressed at the neurovascular unit (NVU) play an important role in drug delivery to the brain and have been demonstrated to be involved in Alzheimer's disease (AD) pathogenesis. However, our knowledge of quantitative changes in transporter absolute protein expression and functionality in vivo in NVU in AD patients and animal models is limited. The study aim was to investigate alterations in protein expression of ABC and SLC transporters in the isolated brain microvessels and brain prefrontal cortices of a widely used model of familial AD, 5xFAD mice (8 months old), using a sensitive liquid chromatography tandem mass spectrometry-based quantitative targeted absolute proteomic approach. Moreover, we examined alterations in brain prefrontal cortical and plasmatic levels of transporter substrates in 5xFAD mice compared to age-matched wild-type (WT) controls. ASCT1 (encoded by Slc1a4) protein expression in the isolated brain microvessels and brain prefrontal cortices of 5xFAD mice was twice higher compared to WT controls (p = 0.01). Brain cortical levels of ASCT1 substrate, serine, were increased in 5xFAD mice compared to WT animals. LAT1 (encoded by Slc7a5) and 4F2hc (encoded by Slc3a2) protein expressions were significantly altered in the isolated brain microvessels of 5xFAD mice compared to WT controls (p = 0.008 and p = 0.05, respectively). Overall, the study provides important information, which is crucial for the optimal use of the 5xFAD mouse model in AD drug development and for investigating novel drug delivery approaches. In addition, the findings of the study shed light on the novel potential mechanisms underlying AD pathogenesis.
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Affiliation(s)
- Elena Puris
- Institute of Pharmacy and Molecular Biotechnology, Ruprecht-Karls-University, Im Neuenheimer Feld 329, 69120 Heidelberg, Germany
| | - Liudmila Saveleva
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
| | - Izaque de Sousa Maciel
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
| | - Katja M. Kanninen
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
| | - Seppo Auriola
- School of Pharmacy, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
| | - Gert Fricker
- Institute of Pharmacy and Molecular Biotechnology, Ruprecht-Karls-University, Im Neuenheimer Feld 329, 69120 Heidelberg, Germany
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Huttunen J, Adla SK, Markowicz-Piasecka M, Huttunen KM. Increased/Targeted Brain (Pro)Drug Delivery via Utilization of Solute Carriers (SLCs). Pharmaceutics 2022; 14:pharmaceutics14061234. [PMID: 35745806 PMCID: PMC9228667 DOI: 10.3390/pharmaceutics14061234] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 06/06/2022] [Accepted: 06/07/2022] [Indexed: 02/04/2023] Open
Abstract
Membrane transporters have a crucial role in compounds’ brain drug delivery. They allow not only the penetration of a wide variety of different compounds to cross the endothelial cells of the blood–brain barrier (BBB), but also the accumulation of them into the brain parenchymal cells. Solute carriers (SLCs), with nearly 500 family members, are the largest group of membrane transporters. Unfortunately, not all SLCs are fully characterized and used in rational drug design. However, if the structural features for transporter interactions (binding and translocation) are known, a prodrug approach can be utilized to temporarily change the pharmacokinetics and brain delivery properties of almost any compound. In this review, main transporter subtypes that are participating in brain drug disposition or have been used to improve brain drug delivery across the BBB via the prodrug approach, are introduced. Moreover, the ability of selected transporters to be utilized in intrabrain drug delivery is discussed. Thus, this comprehensive review will give insights into the methods, such as computational drug design, that should be utilized more effectively to understand the detailed transport mechanisms. Moreover, factors, such as transporter expression modulation pathways in diseases that should be taken into account in rational (pro)drug development, are considered to achieve successful clinical applications in the future.
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Affiliation(s)
- Johanna Huttunen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland; (J.H.); (S.K.A.)
| | - Santosh Kumar Adla
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland; (J.H.); (S.K.A.)
- Institute of Organic Chemistry and Biochemistry (IOCB), Czech Academy of Sciences, Flemingovo Namesti 542/2, 160 00 Prague, Czech Republic
| | - Magdalena Markowicz-Piasecka
- Department of Pharmaceutical Chemistry, Drug Analysis and Radiopharmacy, Medical University of Lodz, ul. Muszyńskiego 1, 90-151 Lodz, Poland;
| | - Kristiina M. Huttunen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland; (J.H.); (S.K.A.)
- Correspondence:
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Altered protein expression of membrane transporters in isolated cerebral microvessels and brain cortex of a rat Alzheimer's disease model. Neurobiol Dis 2022; 169:105741. [DOI: 10.1016/j.nbd.2022.105741] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 03/25/2022] [Accepted: 04/20/2022] [Indexed: 01/28/2023] Open
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The blood-brain barrier in aging and neurodegeneration. Mol Psychiatry 2022; 27:2659-2673. [PMID: 35361905 PMCID: PMC9156404 DOI: 10.1038/s41380-022-01511-z] [Citation(s) in RCA: 157] [Impact Index Per Article: 78.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 01/24/2022] [Accepted: 02/24/2022] [Indexed: 12/01/2022]
Abstract
The blood-brain barrier (BBB) is vital for maintaining brain homeostasis by enabling an exquisite control of exchange of compounds between the blood and the brain parenchyma. Moreover, the BBB prevents unwanted toxins and pathogens from entering the brain. This barrier, however, breaks down with age and further disruption is a hallmark of many age-related disorders. Several drugs have been explored, thus far, to protect or restore BBB function. With the recent connection between the BBB and gut microbiota, microbial-derived metabolites have been explored for their capabilities to protect and restore BBB physiology. This review, will focus on the vital components that make up the BBB, dissect levels of disruption of the barrier, and discuss current drugs and therapeutics that maintain barrier integrity and the recent discoveries of effects microbial-derived metabolites have on BBB physiology.
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Sabatino L, Federighi G, Del Seppia C, Lapi D, Costagli C, Scuri R, Iervasi G. Thyroid hormone deiodinases response in brain of spontaneausly hypertensive rats after hypotensive effects induced by mandibular extension. Endocrine 2021; 74:100-107. [PMID: 33761105 DOI: 10.1007/s12020-021-02684-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 03/05/2021] [Indexed: 01/08/2023]
Abstract
PURPOSE The deiodinases activate or inactivate the thyroid hormones (TH) in virtually all tissues in both physiological and pathological conditions. The three deiodinases, DIO1, DIO2, and DIO3, have different catalytic functions and regulate TH tissue distribution. The aim of the present study was to evaluate the modulation of gene expression of the deiodinases and TH transporters and protein levels of DIO1 in parietal and frontal areas of cerebral cortex of spontaneously hypertensive rats (SHRs), after two successive mandibular extensions (ME). METHODS ME was performed on anesthetized rats by a dilatator appropriately designed and real-time PCR and western blotting techniques were employed for gene expression and protein level study. RESULTS Mean blood pressure (MBP) significantly decreased in 2ME-treated rats when compared to sham-operated rats (p < 0.001) and this decrease lasted for the entire observation period. In gene expression analysis, in 2ME-treated rats we did not observe any significant variation of DIO1 and DIO3 with respect to the sham-operated rats. Differently, DIO2 gene expression significantly increased in frontal area of 2ME-treated rats, with respect to sham-operated rats (p < 0.01). Furthermore, in parietal area, protein levels of DIO1 in 2ME-treated rats were significantly higher than in sham-operated rats (p < 0.01). Moreover MCT8 and OATP1C1 both resulted significantly higher (p < 0.05 and p < 0.001) in sham frontal cortex. CONCLUSION In summary, our data on SHRs, while confirming the hypotensive effect of two MEs, show that the treatment also solicits the three deiodinases production in the cerebral cortex.
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Affiliation(s)
| | - Giuseppe Federighi
- Department of Translational Research on New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | | | - Dominga Lapi
- Department of Biology, University of Pisa, Pisa, Italy
| | - Chiara Costagli
- Department of Translational Research on New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | - Rossana Scuri
- Department of Translational Research on New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
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Oliveira KC, Laureano-Melo R, da Conceição RR, de Souza JS, da Silva Cortês W, Sato MA, Chiamolera MI, Maciel RM, Giannocco G. Thyroxine replacement modifies changes in deiodinase and thyroid hormone transporter expression induced by subclinical hypothyroidism in rats. Hormones (Athens) 2021; 20:101-110. [PMID: 32996026 DOI: 10.1007/s42000-020-00247-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 09/17/2020] [Indexed: 10/23/2022]
Abstract
PURPOSE The potential benefits of treating subclinical hypothyroidism (SCH) are unclear and still controversial. Thus, we surgically induced SCH in rats and evaluated the effects of thyroxine (T4) replacement on the gene expression levels of deiodinases and thyroid hormone (TH) transporters in different tissues. METHODS SCH was induced by hemithyroid electrocauterization. The control animals underwent the same surgical procedure but were not subjected to electrocauterization (sham). After 14 days, half of the SCH animals were treated with T4 (SCH + T4). At the end of the experimental protocol, all of the rats were euthanized, serum hormone concentrations were measured, and RNA analyses were performed on different tissues and organs. RESULTS Consistent with previous studies, we observed increased TSH levels, normal TH levels, and reduced hypothalamic TRH expression in the SCH group. Additionally, Dio2 mRNA expression was downregulated in the hippocampus and pituitary, and Dio1 was upregulated in the kidney and pituitary of the SCH animals. The changes in Dio3 expression were tissue-specific. Concerning TH transporters, Mct10 expression was upregulated in the pituitary, kidney, hypothalamus, and hippocampus, and Mct8 expression was downregulated in the kidney of the SCH group. Crym expression was upregulated in the kidney and pituitary. Notably, T4 replacement significantly attenuated serum TSH levels and reverted Dio1, Dio2, Mct10, and Crym expression in the pituitary, hippocampus, and kidney to levels that were similar to the sham group. Tissue-specific responses were also observed in the liver and hypothalamus. CONCLUSION Our results indicate that treatment of SCH should be considered before the appearance of clinical symptoms of hypothyroidism.
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Affiliation(s)
- Kelen Carneiro Oliveira
- Laboratório de Endocrinologia Molecular e Translacional- LEMT, Divisão de Endocrinologia, Departamento de Medicina, Universidade Federal de São Paulo (UNIFESP), Rua Pedro de Toledo, 669, Vila Clementino, São Paulo, SP, 04039032, Brazil
| | - Roberto Laureano-Melo
- Programa Multicêntrico de Pós-Graduação em Ciências Fisiológicas, Instituto de Ciências Biológicas e da Saúde, Universidade Federal Rural do Rio de Janeiro Brazil; Federal Rural University of Rio de Janeiro, BR 465, Km 7, PQ Room 01, Seropedica, Rio de Janeiro, 23897-000, Brazil
| | - Rodrigo Rodrigues da Conceição
- Laboratório de Endocrinologia Molecular e Translacional- LEMT, Divisão de Endocrinologia, Departamento de Medicina, Universidade Federal de São Paulo (UNIFESP), Rua Pedro de Toledo, 669, Vila Clementino, São Paulo, SP, 04039032, Brazil.
| | - Janaina Sena de Souza
- Laboratório de Endocrinologia Molecular e Translacional- LEMT, Divisão de Endocrinologia, Departamento de Medicina, Universidade Federal de São Paulo (UNIFESP), Rua Pedro de Toledo, 669, Vila Clementino, São Paulo, SP, 04039032, Brazil
| | - Wellington da Silva Cortês
- Programa Multicêntrico de Pós-Graduação em Ciências Fisiológicas, Instituto de Ciências Biológicas e da Saúde, Universidade Federal Rural do Rio de Janeiro Brazil; Federal Rural University of Rio de Janeiro, BR 465, Km 7, PQ Room 01, Seropedica, Rio de Janeiro, 23897-000, Brazil
| | - Mônica Akemi Sato
- Departamento de Morfologia e Fisiologia, Faculdade de Medicina do ABC, Av. Lauro Gomes, 2000 - Vila Sacadura Cabral, Santo André, SP, 09060-870, Brazil
| | - Maria Izabel Chiamolera
- Laboratório de Endocrinologia Molecular e Translacional- LEMT, Divisão de Endocrinologia, Departamento de Medicina, Universidade Federal de São Paulo (UNIFESP), Rua Pedro de Toledo, 669, Vila Clementino, São Paulo, SP, 04039032, Brazil
| | - Rui Monteiro Maciel
- Laboratório de Endocrinologia Molecular e Translacional- LEMT, Divisão de Endocrinologia, Departamento de Medicina, Universidade Federal de São Paulo (UNIFESP), Rua Pedro de Toledo, 669, Vila Clementino, São Paulo, SP, 04039032, Brazil
| | - Gisele Giannocco
- Laboratório de Endocrinologia Molecular e Translacional- LEMT, Divisão de Endocrinologia, Departamento de Medicina, Universidade Federal de São Paulo (UNIFESP), Rua Pedro de Toledo, 669, Vila Clementino, São Paulo, SP, 04039032, Brazil.
- Departamento de Ciências Biológicas, Universidade Federal de São Paulo (UNIFESP), R. Prof. Artur Riedel, 275 - Jd. Eldorado, Diadema, SP, 09972-270, Brazil.
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Luongo C, Butruille L, Sébillot A, Le Blay K, Schwaninger M, Heuer H, Demeneix BA, Remaud S. Absence of Both Thyroid Hormone Transporters MCT8 and OATP1C1 Impairs Neural Stem Cell Fate in the Adult Mouse Subventricular Zone. Stem Cell Reports 2021; 16:337-353. [PMID: 33450189 PMCID: PMC7878696 DOI: 10.1016/j.stemcr.2020.12.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 12/15/2020] [Accepted: 12/15/2020] [Indexed: 02/06/2023] Open
Abstract
Adult neural stem cell (NSC) generation in vertebrate brains requires thyroid hormones (THs). How THs enter the NSC population is unknown, although TH availability determines proliferation and neuronal versus glial progenitor determination in murine subventricular zone (SVZ) NSCs. Mice display neurological signs of the severely disabling human disease, Allan-Herndon-Dudley syndrome, if they lack both MCT8 and OATP1C1 transporters, or MCT8 and deiodinase type 2. We analyzed the distribution of MCT8 and OATP1C1 in adult mouse SVZ. Both are strongly expressed in NSCs and at a lower level in neuronal cell precursors but not in oligodendrocyte progenitors. Next, we analyzed Mct8/Oatp1c1 double-knockout mice, where brain uptake of THs is strongly reduced. NSC proliferation and determination to neuronal fates were severely affected, but not SVZ-oligodendroglial progenitor generation. This work highlights how tight control of TH availability determines NSC function and glial-neuron cell-fate choice in adult brains.
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Affiliation(s)
- Cristina Luongo
- UMR 7221 Phyma, CNRS/Muséum National d'Histoire Naturelle, 75005 Paris, France
| | - Lucile Butruille
- UMR 7221 Phyma, CNRS/Muséum National d'Histoire Naturelle, 75005 Paris, France
| | - Anthony Sébillot
- UMR 7221 Phyma, CNRS/Muséum National d'Histoire Naturelle, 75005 Paris, France
| | - Karine Le Blay
- UMR 7221 Phyma, CNRS/Muséum National d'Histoire Naturelle, 75005 Paris, France
| | - Markus Schwaninger
- Institute for Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, 23562 Lübeck, Germany
| | - Heike Heuer
- Department of Endocrinology, Diabetes and Metabolism, University of Duisburg-Essen, 45122 Essen, Germany
| | - Barbara A Demeneix
- UMR 7221 Phyma, CNRS/Muséum National d'Histoire Naturelle, 75005 Paris, France
| | - Sylvie Remaud
- UMR 7221 Phyma, CNRS/Muséum National d'Histoire Naturelle, 75005 Paris, France.
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Wilpert NM, Krueger M, Opitz R, Sebinger D, Paisdzior S, Mages B, Schulz A, Spranger J, Wirth EK, Stachelscheid H, Mergenthaler P, Vajkoczy P, Krude H, Kühnen P, Bechmann I, Biebermann H. Spatiotemporal Changes of Cerebral Monocarboxylate Transporter 8 Expression. Thyroid 2020; 30:1366-1383. [PMID: 32143555 DOI: 10.1089/thy.2019.0544] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Background: Mutations of monocarboxylate transporter 8 (MCT8), a thyroid hormone (TH)-specific transmembrane transporter, cause a severe neurodevelopmental disorder, the Allan-Herndon-Dudley syndrome. In MCT8 deficiency, TH is not able to reach those areas of the brain where TH uptake depends on MCT8. Currently, therapeutic options for MCT8-deficient patients are missing, as TH treatment is not successful in improving neurological deficits. Available data on MCT8 protein and transcript levels indicate complex expression patterns in neural tissue depending on species, brain region, sex, and age. However, information on human MCT8 expression is still scattered and additional efforts are needed to map sites of MCT8 expression in neurovascular units and neural tissue. This is of importance because new therapeutic strategies for this disease are urgently needed. Methods: To identify regions and time windows of MCT8 expression, we used highly specific antibodies against MCT8 to perform immunofluorescence labeling of postnatal murine brains, adult human brain tissue, and human cerebral organoids. Results: Qualitative and quantitative analyses of murine brain samples revealed stable levels of MCT8 protein expression in endothelial cells of the blood-brain barrier (BBB), choroid plexus epithelial cells, and tanycytes during postnatal development. Conversely, the neuronal MCT8 protein expression that was robustly detectable in specific brain regions of young mice strongly declined with age. Similarly, MCT8 immunoreactivity in adult human brain tissue was largely confined to endothelial cells of the BBB. Recently, cerebral organoids emerged as promising models of human neural development and our first analyses of forebrain-like organoids revealed MCT8 expression in early neuronal progenitor cell populations. Conclusions: With respect to MCT8-deficient conditions, our analyses not only strongly support the contention that the BBB presents a lifelong barrier to TH uptake but also highlight the need to decipher the TH transport role of MCT8 in early neuronal cell populations in more detail. Improving the understanding of the spatiotemporal expression in latter barriers will be critical for therapeutic strategies addressing MCT8 deficiency in the future.
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Affiliation(s)
- Nina-Maria Wilpert
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Experimental Pediatric Endocrinology, Berlin, Germany
| | - Martin Krueger
- Institute of Anatomy, University of Leipzig, Leipzig, Germany
| | - Robert Opitz
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Experimental Pediatric Endocrinology, Berlin, Germany
| | - David Sebinger
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Experimental Pediatric Endocrinology, Berlin, Germany
| | - Sarah Paisdzior
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Experimental Pediatric Endocrinology, Berlin, Germany
| | - Bianca Mages
- Institute of Anatomy, University of Leipzig, Leipzig, Germany
| | - Angela Schulz
- Rudolf Schönheimer Institute of Biochemistry, Molecular Biochemistry, University of Leipzig, Leipzig, Germany
| | - Joachim Spranger
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Endocrinology, Diabetes and Nutrition, Berlin, Germany
| | - Eva K Wirth
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Endocrinology, Diabetes and Nutrition, Berlin, Germany
| | - Harald Stachelscheid
- Stem Cell Core Facility, Berlin Institute of Health, Berlin, Germany
- Charité - Universitätsmedizin Berlin, Berlin-Brandenburg Center for Regenerative Therapies (BCRT), Berlin, Germany
| | - Philipp Mergenthaler
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Experimental Neurology, Department of Neurology, Center for Stroke Research Berlin, Berlin, Germany
- Berlin Institute of Health (BIH), Berlin, Germany
| | - Peter Vajkoczy
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Neurosurgery, Berlin, Germany
| | - Heiko Krude
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Experimental Pediatric Endocrinology, Berlin, Germany
| | - Peter Kühnen
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Experimental Pediatric Endocrinology, Berlin, Germany
| | - Ingo Bechmann
- Institute of Anatomy, University of Leipzig, Leipzig, Germany
| | - Heike Biebermann
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Experimental Pediatric Endocrinology, Berlin, Germany
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13
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Groeneweg S, van Geest FS, Peeters RP, Heuer H, Visser WE. Thyroid Hormone Transporters. Endocr Rev 2020; 41:5637505. [PMID: 31754699 DOI: 10.1210/endrev/bnz008] [Citation(s) in RCA: 98] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 11/07/2019] [Indexed: 02/08/2023]
Abstract
Thyroid hormone transporters at the plasma membrane govern intracellular bioavailability of thyroid hormone. Monocarboxylate transporter (MCT) 8 and MCT10, organic anion transporting polypeptide (OATP) 1C1, and SLC17A4 are currently known as transporters displaying the highest specificity toward thyroid hormones. Structure-function studies using homology modeling and mutational screens have led to better understanding of the molecular basis of thyroid hormone transport. Mutations in MCT8 and in OATP1C1 have been associated with clinical disorders. Different animal models have provided insight into the functional role of thyroid hormone transporters, in particular MCT8. Different treatment strategies for MCT8 deficiency have been explored, of which thyroid hormone analogue therapy is currently applied in patients. Future studies may reveal the identity of as-yet-undiscovered thyroid hormone transporters. Complementary studies employing animal and human models will provide further insight into the role of transporters in health and disease. (Endocrine Reviews 41: 1 - 55, 2020).
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Affiliation(s)
- Stefan Groeneweg
- Department of Internal Medicine, Erasmus Medical Center, Rotterdam, the Netherlands Academic Center for Thyroid Diseases, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Ferdy S van Geest
- Department of Internal Medicine, Erasmus Medical Center, Rotterdam, the Netherlands Academic Center for Thyroid Diseases, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Robin P Peeters
- Department of Internal Medicine, Erasmus Medical Center, Rotterdam, the Netherlands Academic Center for Thyroid Diseases, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Heike Heuer
- Department of Endocrinology, Diabetes and Metabolism, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - W Edward Visser
- Department of Internal Medicine, Erasmus Medical Center, Rotterdam, the Netherlands Academic Center for Thyroid Diseases, Erasmus Medical Center, Rotterdam, the Netherlands
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14
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Chen QQ, Haikal C, Li W, Li JY. Gut Inflammation in Association With Pathogenesis of Parkinson's Disease. Front Mol Neurosci 2019; 12:218. [PMID: 31572126 PMCID: PMC6753187 DOI: 10.3389/fnmol.2019.00218] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 08/29/2019] [Indexed: 12/18/2022] Open
Abstract
Parkinson’s disease (PD) is a neurodegenerative disease that is generally thought to be caused by multiple factors, including environmental and genetic factors. Emerging evidence suggests that intestinal disturbances, such as constipation, are common non-motor symptoms of PD. Gut inflammation may be closely associated with pathogenesis in PD. This review aims to discuss the cross-talk between gut inflammation and PD pathology initiation and progression. Firstly, we will highlight the studies demonstrating how gut inflammation is related to PD. Secondly, we will analyze how gut inflammation spreads from the gastro-intestine to the brain. Here, we will mainly discuss the neural pathway of pathologic α-syn and the systemic inflammatory routes. Thereafter, we will address how alterations in the brain subsequently lead to dopaminergic neuron degeneration, in which oxidative stress, glutamate excitotoxicity, T cell driven inflammation and cyclooxygenase-2 (COX-2) are involved. We conclude a model of PD triggered by gut inflammation, which provides a new angle to understand the mechanisms of the disease.
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Affiliation(s)
- Qian-Qian Chen
- Institute of Neuroscience, College of Life and Health Sciences, Northeastern University, Shenyang, China
| | - Caroline Haikal
- Neural Plasticity and Repair Unit, Wallenberg Neuroscience Center, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Wen Li
- Institute of Health Sciences, China Medical University, Shenyang, China
| | - Jia-Yi Li
- Neural Plasticity and Repair Unit, Wallenberg Neuroscience Center, Department of Experimental Medical Science, Lund University, Lund, Sweden.,Institute of Health Sciences, China Medical University, Shenyang, China
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15
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Bianco AC, Dumitrescu A, Gereben B, Ribeiro MO, Fonseca TL, Fernandes GW, Bocco BMLC. Paradigms of Dynamic Control of Thyroid Hormone Signaling. Endocr Rev 2019; 40:1000-1047. [PMID: 31033998 PMCID: PMC6596318 DOI: 10.1210/er.2018-00275] [Citation(s) in RCA: 140] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 03/15/2019] [Indexed: 12/17/2022]
Abstract
Thyroid hormone (TH) molecules enter cells via membrane transporters and, depending on the cell type, can be activated (i.e., T4 to T3 conversion) or inactivated (i.e., T3 to 3,3'-diiodo-l-thyronine or T4 to reverse T3 conversion). These reactions are catalyzed by the deiodinases. The biologically active hormone, T3, eventually binds to intracellular TH receptors (TRs), TRα and TRβ, and initiate TH signaling, that is, regulation of target genes and other metabolic pathways. At least three families of transmembrane transporters, MCT, OATP, and LAT, facilitate the entry of TH into cells, which follow the gradient of free hormone between the extracellular fluid and the cytoplasm. Inactivation or marked downregulation of TH transporters can dampen TH signaling. At the same time, dynamic modifications in the expression or activity of TRs and transcriptional coregulators can affect positively or negatively the intensity of TH signaling. However, the deiodinases are the element that provides greatest amplitude in dynamic control of TH signaling. Cells that express the activating deiodinase DIO2 can rapidly enhance TH signaling due to intracellular buildup of T3. In contrast, TH signaling is dampened in cells that express the inactivating deiodinase DIO3. This explains how THs can regulate pathways in development, metabolism, and growth, despite rather stable levels in the circulation. As a consequence, TH signaling is unique for each cell (tissue or organ), depending on circulating TH levels and on the exclusive blend of transporters, deiodinases, and TRs present in each cell. In this review we explore the key mechanisms underlying customization of TH signaling during development, in health and in disease states.
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Affiliation(s)
- Antonio C Bianco
- Section of Endocrinology, Diabetes, and Metabolism, University of Chicago Medical Center, Chicago, Illinois
| | - Alexandra Dumitrescu
- Section of Endocrinology, Diabetes, and Metabolism, University of Chicago Medical Center, Chicago, Illinois
| | - Balázs Gereben
- Department of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Miriam O Ribeiro
- Developmental Disorders Program, Center of Biologic Sciences and Health, Mackenzie Presbyterian University, São Paulo, São Paulo, Brazil
| | - Tatiana L Fonseca
- Section of Endocrinology, Diabetes, and Metabolism, University of Chicago Medical Center, Chicago, Illinois
| | - Gustavo W Fernandes
- Section of Endocrinology, Diabetes, and Metabolism, University of Chicago Medical Center, Chicago, Illinois
| | - Barbara M L C Bocco
- Section of Endocrinology, Diabetes, and Metabolism, University of Chicago Medical Center, Chicago, Illinois
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16
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Finch-Edmondson M, Morgan C, Hunt RW, Novak I. Emergent Prophylactic, Reparative and Restorative Brain Interventions for Infants Born Preterm With Cerebral Palsy. Front Physiol 2019; 10:15. [PMID: 30745876 PMCID: PMC6360173 DOI: 10.3389/fphys.2019.00015] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 01/08/2019] [Indexed: 12/13/2022] Open
Abstract
Worldwide, an estimated 15 million babies are born preterm (<37 weeks' gestation) every year. Despite significant improvements in survival rates, preterm infants often face a lifetime of neurodevelopmental disability including cognitive, behavioral, and motor impairments. Indeed, prematurity remains the largest risk factor for the development of cerebral palsy. The developing brain of the preterm infant is particularly fragile; preterm babies exhibit varying severities of cerebral palsy arising from reductions in both cerebral white and gray matter volumes, as well as altered brain microstructure and connectivity. Current intensive care therapies aim to optimize cardiovascular and respiratory function to protect the brain from injury by preserving oxygenation and blood flow. If a brain injury does occur, definitive diagnosis of cerebral palsy in the first few hours and weeks of life is difficult, especially when the lesions are subtle and not apparent on cranial ultrasound. However, early diagnosis of mildly affected infants is critical, because these are the patients most likely to respond to emergent treatments inducing neuroplasticity via high-intensity motor training programs and regenerative therapies involving stem cells. A current controversy is whether to test universal treatment in all infants at risk of brain injury, accepting that some patients never required treatment, because the perceived potential benefits outweigh the risk of harm. Versus, waiting for a diagnosis before commencing targeted treatment for infants with a brain injury, and potentially missing the therapeutic window. In this review, we discuss the emerging prophylactic, reparative, and restorative brain interventions for infants born preterm, who are at high risk of developing cerebral palsy. We examine the current evidence, considering the timing of the intervention with relation to the proposed mechanism/s of action. Finally, we consider the development of novel markers of preterm brain injury, which will undoubtedly lead to improved diagnostic and prognostic capability, and more accurate instruments to assess the efficacy of emerging interventions for this most vulnerable group of infants.
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Affiliation(s)
- Megan Finch-Edmondson
- The Discipline of Child and Adolescent Health, The Children's Hospital at Westmead Clinical School, The University of Sydney Medical School, Sydney, NSW, Australia
- Cerebral Palsy Alliance Research Institute, The University of Sydney, Sydney, NSW, Australia
| | - Catherine Morgan
- The Discipline of Child and Adolescent Health, The Children's Hospital at Westmead Clinical School, The University of Sydney Medical School, Sydney, NSW, Australia
- Cerebral Palsy Alliance Research Institute, The University of Sydney, Sydney, NSW, Australia
| | - Rod W. Hunt
- Department of Neonatal Medicine, The Royal Children's Hospital, Melbourne, VIC, Australia
- Department of Paediatrics, University of Melbourne, Melbourne, VIC, Australia
- Neonatal Research, Murdoch Children's Research Institute, Melbourne, VIC, Australia
- Department of Obstetrics and Gynaecology, Monash University, Melbourne, VIC, Australia
| | - Iona Novak
- The Discipline of Child and Adolescent Health, The Children's Hospital at Westmead Clinical School, The University of Sydney Medical School, Sydney, NSW, Australia
- Cerebral Palsy Alliance Research Institute, The University of Sydney, Sydney, NSW, Australia
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17
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Morris G, Fernandes BS, Puri BK, Walker AJ, Carvalho AF, Berk M. Leaky brain in neurological and psychiatric disorders: Drivers and consequences. Aust N Z J Psychiatry 2018; 52:924-948. [PMID: 30231628 DOI: 10.1177/0004867418796955] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND The blood-brain barrier acts as a highly regulated interface; its dysfunction may exacerbate, and perhaps initiate, neurological and neuropsychiatric disorders. METHODS In this narrative review, focussing on redox, inflammatory and mitochondrial pathways and their effects on the blood-brain barrier, a model is proposed detailing mechanisms which might explain how increases in blood-brain barrier permeability occur and can be maintained with increasing inflammatory and oxidative and nitrosative stress being the initial drivers. RESULTS Peripheral inflammation, which is causatively implicated in the pathogenesis of major psychiatric disorders, is associated with elevated peripheral pro-inflammatory cytokines, which in turn cause increased blood-brain barrier permeability. Reactive oxygen species, such as superoxide radicals and hydrogen peroxide, and reactive nitrogen species, such as nitric oxide and peroxynitrite, play essential roles in normal brain capillary endothelial cell functioning; however, chronically elevated oxidative and nitrosative stress can lead to mitochondrial dysfunction and damage to the blood-brain barrier. Activated microglia, redox control of which is mediated by nitric oxide synthases and nicotinamide adenine dinucleotide phosphate (NADPH) oxidases, secrete neurotoxic molecules such as reactive oxygen species, nitric oxide, prostaglandin, cyclooxygenase-2, quinolinic acid, several chemokines (including monocyte chemoattractant protein-1 [MCP-1], C-X-C motif chemokine ligand 1 [CXCL-1] and macrophage inflammatory protein 1α [MIP-1α]) and the pro-inflammatory cytokines interleukin-6, tumour necrosis factor-α and interleukin-1β, which can exert a detrimental effect on blood-brain barrier integrity and function. Similarly, reactive astrocytes produce neurotoxic molecules such as prostaglandin E2 and pro-inflammatory cytokines, which can cause a 'leaky brain'. CONCLUSION Chronic inflammatory and oxidative and nitrosative stress is associated with the development of a 'leaky gut'. The following evidence-based approaches, which address the leaky gut and blood-brain barrier dysfunction, are suggested as potential therapeutic interventions for neurological and neuropsychiatric disorders: melatonin, statins, probiotics containing Bifidobacteria and Lactobacilli, N-acetylcysteine, and prebiotics containing fructo-oligosaccharides and galacto-oligosaccharides.
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Affiliation(s)
- Gerwyn Morris
- 1 IMPACT Strategic Research Centre, Deakin University School of Medicine, and Barwon Health, Geelong, VIC, Australia
| | - Brisa S Fernandes
- 1 IMPACT Strategic Research Centre, Deakin University School of Medicine, and Barwon Health, Geelong, VIC, Australia.,2 Centre for Addiction and Mental Health (CAMH) and Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Basant K Puri
- 3 Department of Medicine, Hammersmith Hospital, Imperial College London, London, UK
| | - Adam J Walker
- 1 IMPACT Strategic Research Centre, Deakin University School of Medicine, and Barwon Health, Geelong, VIC, Australia
| | - Andre F Carvalho
- 2 Centre for Addiction and Mental Health (CAMH) and Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Michael Berk
- 1 IMPACT Strategic Research Centre, Deakin University School of Medicine, and Barwon Health, Geelong, VIC, Australia.,4 Orygen, The National Centre of Excellence in Youth Mental Health, The Department of Psychiatry and The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, Australia
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18
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Wittmann G, Lechan RM. Prss56 expression in the rodent hypothalamus: Inverse correlation with pro-opiomelanocortin suggests oscillatory gene expression in adult rat tanycytes. J Comp Neurol 2018; 526:2444-2461. [PMID: 30242838 DOI: 10.1002/cne.24504] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 06/27/2018] [Accepted: 07/12/2018] [Indexed: 11/11/2022]
Abstract
We recently reported that the number of hypothalamic tanycytes expressing pro-opiomelanocortin (Pomc) is highly variable among brains of adult rats. While its cause and significance remain unknown, identifying other variably expressed genes in tanycytes may help understand this curious phenomenon. In this in situ hybridization study, we report that the Prss56 gene, which encodes a trypsin-like serine protease and is expressed in neural stem/progenitor cells, shows a similarly variable mRNA expression in tanycytes of adult rats and correlates inversely with tanycyte Pomc mRNA. Prss56 was expressed in α1, β1, subsets of α2, and some median eminence γ tanycytes, but virtually absent from β2 tanycytes. Prss56 was also expressed in vimentin positive tanycyte-like cells in the parenchyma of the ventromedial and arcuate nuclei, and in thyrotropin beta subunit-expressing cells of the pars tuberalis of the pituitary. In contrast to adults, Prss56 expression was uniformly high in tanycytes in adolescent rats. In mice, Prss56-expressing tanycytes and parenchymal cells were also observed but fewer in number and without significant variations. The results identify Prss56 as a second gene that is expressed variably in tanycytes of adult rats. We propose that the variable, inversely correlating expression of Prss56 and Pomc reflect periodically oscillating gene expression in tanycytes rather than stable expression levels that vary between individual rats. A possible functional link between Prss56 and POMC, and Prss56 as a potential marker for migrating tanycytes are discussed.
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Affiliation(s)
- Gábor Wittmann
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, Tupper Research Institute, Tufts Medical Center, Boston, Massachusetts
| | - Ronald M Lechan
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, Tupper Research Institute, Tufts Medical Center, Boston, Massachusetts.,Department of Neuroscience, Tufts University School of Medicine, Boston, Massachusetts
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19
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Bank JHH, Cubuk C, Wilson D, Rijntjes E, Kemmling J, Markovsky H, Barrett P, Herwig A. Gene expression analysis and microdialysis suggest hypothalamic triiodothyronine (T3) gates daily torpor in Djungarian hamsters (Phodopus sungorus). J Comp Physiol B 2017; 187:857-868. [PMID: 28365894 DOI: 10.1007/s00360-017-1086-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 01/19/2017] [Accepted: 03/07/2017] [Indexed: 11/30/2022]
Abstract
Thyroid hormones play an important role in regulating seasonal adaptations of mammals. Several studies suggested that reduced availability of 3,3',5-triiodothyronine (T3) in the hypothalamus is required for the physiological adaptation to winter in Djungarian hamsters. We have previously shown that T3 is involved in the regulation of daily torpor, but it remains unclear, whether T3 affects torpor by central or peripheral mechanisms. To determine the effect of T3 concentrations within the hypothalamus in regulating daily torpor, we tested the hypothesis that low hypothalamic T3 metabolism would favour torpor and high T3 concentrations would not. In experiment 1 gene expression in torpid hamsters was assessed for transporters carrying thyroid hormones between cerebrospinal fluid and hypothalamic cells and for deiodinases enzymes, activating or inactivating T3 within hypothalamic cells. Gene expression analysis suggests reduced T3 in hypothalamic cells during torpor. In experiment 2, hypothalamic T3 concentrations were altered via microdialysis and torpor behaviour was continuously monitored by implanted body temperature transmitters. Increased T3 concentrations in the hypothalamus reduced expression of torpor as well as torpor bout duration and depth. Subsequent analysis of gene expression in the ependymal layer of the third ventricle showed clear up-regulation of T3 inactivating deiodinase 3 but no changes in several other genes related to photoperiodic adaptations in hamsters. Finally, serum analysis revealed that increased total T3 serum concentrations were not necessary to inhibit torpor expression. Taken together, our results are consistent with the hypothesis that T3 availability within the hypothalamus significantly contributes to the regulation of daily torpor via a central pathway.
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Affiliation(s)
- Jonathan H H Bank
- Biozentrum Grindel und Zoologisches Museum, Universität Hamburg, Martin-Luther-King-Platz 3, 20146, Hamburg, Germany
| | - Ceyda Cubuk
- Biozentrum Grindel und Zoologisches Museum, Universität Hamburg, Martin-Luther-King-Platz 3, 20146, Hamburg, Germany
| | - Dana Wilson
- The Rowett Institute, University of Aberdeen, Bucksburn, Aberdeen, UK
| | - Eddy Rijntjes
- Institut für Experimentelle Endokrinologie, Charité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Julia Kemmling
- Biozentrum Grindel und Zoologisches Museum, Universität Hamburg, Martin-Luther-King-Platz 3, 20146, Hamburg, Germany
| | - Hanna Markovsky
- Biozentrum Grindel und Zoologisches Museum, Universität Hamburg, Martin-Luther-King-Platz 3, 20146, Hamburg, Germany
| | - Perry Barrett
- The Rowett Institute, University of Aberdeen, Bucksburn, Aberdeen, UK
| | - Annika Herwig
- Biozentrum Grindel und Zoologisches Museum, Universität Hamburg, Martin-Luther-King-Platz 3, 20146, Hamburg, Germany.
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20
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Abstract
Thyroid hormones (TH) are endocrine messengers essential for normal development and function of virtually every vertebrate. The hypothalamic-pituitary-thyroid axis is exquisitely modulated to maintain nearly constant TH (T4 and T3) levels in circulation. However peripheral tissues and the CNS control the intracellular availability of TH, suggesting that circulating concentrations of TH are not fully representative of what each cell type sees. Indeed, recent work in the field has identified that TH transporters, deiodinases and thyroid hormone receptor coregulators can strongly control tissue-specific sensitivity to a set amount of TH. Furthermore, the mechanism by which the thyroid hormone receptors regulate target gene expression can vary by gene, tissue and cellular context. This review will highlight novel insights into the machinery that controls the cellular response to TH, which include unique signaling cascades. These findings shed new light into the pathophysiology of human diseases caused by abnormal TH signaling.
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Affiliation(s)
- Arturo Mendoza
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
| | - Anthony N Hollenberg
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA.
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21
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Varatharaj A, Galea I. The blood-brain barrier in systemic inflammation. Brain Behav Immun 2017; 60:1-12. [PMID: 26995317 DOI: 10.1016/j.bbi.2016.03.010] [Citation(s) in RCA: 681] [Impact Index Per Article: 97.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Revised: 03/06/2016] [Accepted: 03/15/2016] [Indexed: 12/22/2022] Open
Abstract
The blood-brain barrier (BBB) plays a key role in maintaining the specialized microenvironment of the central nervous system (CNS), and enabling communication with the systemic compartment. BBB changes occur in several CNS pathologies. Here, we review disruptive and non-disruptive BBB changes in systemic infections and other forms of systemic inflammation, and how these changes may affect CNS function in health and disease. We first describe the structure and function of the BBB, and outline the techniques used to study the BBB in vitro, and in animal and human settings. We then summarise the evidence from a range of models linking BBB changes with systemic inflammation, and the underlying mechanisms. The clinical relevance of these BBB changes during systemic inflammation are discussed in the context of clinically-apparent syndromes such as sickness behaviour, delirium, and septic encephalopathy, as well as neurological conditions such as Alzheimer's disease and multiple sclerosis. We review emerging evidence for two novel concepts: (1) a heightened sensitivity of the diseased, versus healthy, BBB to systemic inflammation, and (2) the contribution of BBB changes induced by systemic inflammation to progression of the primary disease process.
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Affiliation(s)
- Aravinthan Varatharaj
- Clinical Neurosciences, Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Mailpoint 806, Southampton General Hospital, Tremona Road, Southampton SO16 6YD, United Kingdom.
| | - Ian Galea
- Clinical Neurosciences, Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Mailpoint 806, Southampton General Hospital, Tremona Road, Southampton SO16 6YD, United Kingdom.
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22
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Nizamutdinov D, DeMorrow S, McMillin M, Kain J, Mukherjee S, Zeitouni S, Frampton G, Bricker PCS, Hurst J, Shapiro LA. Hepatic alterations are accompanied by changes to bile acid transporter-expressing neurons in the hypothalamus after traumatic brain injury. Sci Rep 2017; 7:40112. [PMID: 28106051 PMCID: PMC5247752 DOI: 10.1038/srep40112] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 12/02/2016] [Indexed: 12/29/2022] Open
Abstract
Annually, there are over 2 million incidents of traumatic brain injury (TBI) and treatment options are non-existent. While many TBI studies have focused on the brain, peripheral contributions involving the digestive and immune systems are emerging as factors involved in the various symptomology associated with TBI. We hypothesized that TBI would alter hepatic function, including bile acid system machinery in the liver and brain. The results show activation of the hepatic acute phase response by 2 hours after TBI, hepatic inflammation by 6 hours after TBI and a decrease in hepatic transcription factors, Gli 1, Gli 2, Gli 3 at 2 and 24 hrs after TBI. Bile acid receptors and transporters were decreased as early as 2 hrs after TBI until at least 24 hrs after TBI. Quantification of bile acid transporter, ASBT-expressing neurons in the hypothalamus, revealed a significant decrease following TBI. These results are the first to show such changes following a TBI, and are compatible with previous studies of the bile acid system in stroke models. The data support the emerging idea of a systemic influence to neurological disorders and point to the need for future studies to better define specific mechanisms of action.
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Affiliation(s)
- Damir Nizamutdinov
- Department of Surgery, Texas A&M University Health Science Center, College of Medicine, Temple, Texas, 76504, USA.,Department of Neurosurgery, Neuroscience Research Institute, Baylor Scott &White Health, Temple, Texas, 76504, USA
| | - Sharon DeMorrow
- Departent of Internal Medicine, Texas A&M University Health Science Center, College of Medicine, Temple, Texas, 76504, USA.,Central Texas Veterans Health Care System, Temple, Texas, 76504, USA
| | - Matthew McMillin
- Departent of Internal Medicine, Texas A&M University Health Science Center, College of Medicine, Temple, Texas, 76504, USA.,Central Texas Veterans Health Care System, Temple, Texas, 76504, USA
| | - Jessica Kain
- Department of Surgery, Texas A&M University Health Science Center, College of Medicine, Temple, Texas, 76504, USA
| | - Sanjib Mukherjee
- Department of Surgery, Texas A&M University Health Science Center, College of Medicine, Temple, Texas, 76504, USA
| | - Suzanne Zeitouni
- Department of Surgery, Texas A&M University Health Science Center, College of Medicine, Temple, Texas, 76504, USA
| | - Gabriel Frampton
- Departent of Internal Medicine, Texas A&M University Health Science Center, College of Medicine, Temple, Texas, 76504, USA.,Central Texas Veterans Health Care System, Temple, Texas, 76504, USA
| | - Paul Clint S Bricker
- Department of Surgery, Texas A&M University Health Science Center, College of Medicine, Temple, Texas, 76504, USA
| | - Jacob Hurst
- Department of Surgery, Texas A&M University Health Science Center, College of Medicine, Temple, Texas, 76504, USA
| | - Lee A Shapiro
- Department of Surgery, Texas A&M University Health Science Center, College of Medicine, Temple, Texas, 76504, USA.,Department of Neurosurgery, Neuroscience Research Institute, Baylor Scott &White Health, Temple, Texas, 76504, USA
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23
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Abstract
The activity of the hypothalamus-pituitary-thyroid axis (HPT) is coordinated by hypophysiotropic thyrotropin releasing hormone (TRH) neurons present in the paraventricular nucleus of the hypothalamus. Hypophysiotropic TRH neurons act as energy sensors. TRH controls the synthesis and release of thyrotropin, which activates the synthesis and secretion of thyroid hormones; in target tissues, transporters and deiodinases control their local availability. Thyroid hormones regulate many functions, including energy homeostasis. This review discusses recent evidence that covers several aspects of TRH role in HPT axis regulation. Knowledge about the mechanisms of TRH signaling has steadily increased. New transcription factors engaged in TRH gene expression have been identified, and advances made on how they interact with signaling pathways and define the dynamics of TRH neurons response to acute and/or long-term influences. Albeit yet incomplete, the relationship of TRH neurons activity with positive energy balance has emerged. The importance of tanycytes as a central relay for the feedback control of the axis, as well as for HPT responses to alterations in energy balance, and other stimuli has been reinforced. Finally, some studies have started to shed light on the interference of prenatal and postnatal stress and nutrition on HPT axis programing, which have confirmed the axis susceptibility to early insults.
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Affiliation(s)
- Patricia Joseph-Bravo
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Av. Universidad 2001, 62250, Cuernavaca MOR, Morelos, México.
| | - Lorraine Jaimes-Hoy
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Av. Universidad 2001, 62250, Cuernavaca MOR, Morelos, México
| | - Jean-Louis Charli
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Av. Universidad 2001, 62250, Cuernavaca MOR, Morelos, México
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24
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Wittmann G, Farkas E, Szilvásy-Szabó A, Gereben B, Fekete C, Lechan RM. Variable proopiomelanocortin expression in tanycytes of the adult rat hypothalamus and pituitary stalk. J Comp Neurol 2016; 525:411-441. [PMID: 27503597 DOI: 10.1002/cne.24090] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 08/01/2016] [Accepted: 08/04/2016] [Indexed: 01/21/2023]
Abstract
It is generally believed that proopiomelanocortin (POMC) is expressed exclusively by neurons in the adult rodent brain. Unbeknownst to most researchers, however, Pomc in situ hybridization studies in the rat show specific labeling in the ventral wall of the hypothalamic third ventricle, which is formed by specialized ependymal cells, called tanycytes. Here we characterized this non-neuronal POMC expression in detail using in situ hybridization and immunohistochemical techniques, and report two unique characteristics. First, POMC mRNA and precursor protein expression in non-neuronal cells varies to a great degree as to the extent and abundance of expression. In brains with low-level expression, POMC mRNA and protein was largely confined to a population of tanycytes within the infundibular stalk/caudal median eminence, termed here γ tanycytes, and a subset of closely located β and α2 tanycytes. In brains with high-level expression, POMC mRNA and protein was observed in the vast majority of α2, β, and γ tanycytes. This variability was observed in both adult males and females; of 41 rats between 8 and 15 weeks of age, 17 had low-, 9 intermediate-, and 15 high-level POMC expression in tanycytes. Second, unlike other known POMC-expressing cells, tanycytes rarely contained detectable levels of adrenocorticotropin or α-melanocyte-stimulating hormone. The results indicate either a dynamic spatiotemporal pattern whereby low and high POMC syntheses in tanycytes occur periodically in each brain, or marked interindividual differences that may persist throughout adulthood. Future studies are required to examine these possibilities and elucidate the physiologic importance of POMC in tanycytes. J. Comp. Neurol. 525:411-441, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Gábor Wittmann
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, Tupper Research Institute, Tufts Medical Center, Boston, Massachusetts, 02111
| | - Erzsébet Farkas
- Department of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, 1083, Hungary.,Pázmány Péter Catholic University, Multidisciplinary Doctoral School of Sciences and Technology, Budapest, 1083, Hungary
| | - Anett Szilvásy-Szabó
- Department of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, 1083, Hungary.,Semmelweis University, János Szentágothai PhD School of Neurosciences, Budapest, 1085, Hungary
| | - Balázs Gereben
- Department of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, 1083, Hungary
| | - Csaba Fekete
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, Tupper Research Institute, Tufts Medical Center, Boston, Massachusetts, 02111.,Department of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, 1083, Hungary
| | - Ronald M Lechan
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, Tupper Research Institute, Tufts Medical Center, Boston, Massachusetts, 02111.,Department of Neuroscience, Tufts University School of Medicine, Boston, Massachusetts, 02111
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25
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Little AG. A review of the peripheral levels of regulation by thyroid hormone. J Comp Physiol B 2016; 186:677-88. [DOI: 10.1007/s00360-016-0984-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Revised: 03/23/2016] [Accepted: 03/29/2016] [Indexed: 12/12/2022]
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26
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Glucose Transporters at the Blood-Brain Barrier: Function, Regulation and Gateways for Drug Delivery. Mol Neurobiol 2016; 54:1046-1077. [PMID: 26801191 DOI: 10.1007/s12035-015-9672-6] [Citation(s) in RCA: 201] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 12/17/2015] [Indexed: 12/31/2022]
Abstract
Glucose transporters (GLUTs) at the blood-brain barrier maintain the continuous high glucose and energy demands of the brain. They also act as therapeutic targets and provide routes of entry for drug delivery to the brain and central nervous system for treatment of neurological and neurovascular conditions and brain tumours. This article first describes the distribution, function and regulation of glucose transporters at the blood-brain barrier, the major ones being the sodium-independent facilitative transporters GLUT1 and GLUT3. Other GLUTs and sodium-dependent transporters (SGLTs) have also been identified at lower levels and under various physiological conditions. It then considers the effects on glucose transporter expression and distribution of hypoglycemia and hyperglycemia associated with diabetes and oxygen/glucose deprivation associated with cerebral ischemia. A reduction in glucose transporters at the blood-brain barrier that occurs before the onset of the main pathophysiological changes and symptoms of Alzheimer's disease is a potential causative effect in the vascular hypothesis of the disease. Mutations in glucose transporters, notably those identified in GLUT1 deficiency syndrome, and some recreational drug compounds also alter the expression and/or activity of glucose transporters at the blood-brain barrier. Approaches for drug delivery across the blood-brain barrier include the pro-drug strategy whereby drug molecules are conjugated to glucose transporter substrates or encapsulated in nano-enabled delivery systems (e.g. liposomes, micelles, nanoparticles) that are functionalised to target glucose transporters. Finally, the continuous development of blood-brain barrier in vitro models is important for studying glucose transporter function, effects of disease conditions and interactions with drugs and xenobiotics.
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27
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Gereben B, McAninch EA, Ribeiro MO, Bianco AC. Scope and limitations of iodothyronine deiodinases in hypothyroidism. Nat Rev Endocrinol 2015; 11:642-652. [PMID: 26416219 PMCID: PMC5003781 DOI: 10.1038/nrendo.2015.155] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The coordinated expression and activity of the iodothyronine deiodinases regulate thyroid hormone levels in hypothyroidism. Once heralded as the pathway underpinning adequate thyroid-hormone replacement therapy with levothyroxine, the role of these enzymes has come into question as they have been implicated in both an inability to normalize serum levels of tri-iodothyronine (T3) and the incomplete resolution of hypothyroid symptoms. These observations, some of which were validated in animal models of levothyroxine monotherapy, challenge the paradigm that tissue levels of T3 and thyroid-hormone signalling can be fully restored by administration of levothyroxine alone. The low serum levels of T3 observed among patients receiving levothyroxine monotherapy occur as a consequence of type 2 iodothyronine deiodinase (DIO2) in the hypothalamus being fairly insensitive to ubiquitination. In addition, residual symptoms of hypothyroidism have been linked to a prevalent polymorphism in the DIO2 gene that might be a risk factor for neurodegenerative disease. Here, we discuss how these novel findings underscore the clinical importance of iodothyronine deiodinases in hypothyroidism and how an improved understanding of these enzymes might translate to therapeutic advances in the care of millions of patients with this condition.
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Affiliation(s)
- Balázs Gereben
- Department of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Szigony Street 43, Budapest H-1083, Hungary
| | - Elizabeth A McAninch
- Division of Endocrinology and Metabolism, Rush University Medical Center, 212 Cohn Building, 1735 West Harrison Street, Chicago, IL 60612, USA
| | - Miriam O Ribeiro
- Developmental Disorders Program, Center for Biological and Health Science, Mackenzie Presbyterian University, Rua da Consolação 930, Building 16, São Paulo, SP 01302, Brazil
| | - Antonio C Bianco
- Division of Endocrinology and Metabolism, Rush University Medical Center, 212 Cohn Building, 1735 West Harrison Street, Chicago, IL 60612, USA
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28
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Wittmann G, Mohácsik P, Balkhi MY, Gereben B, Lechan RM. Endotoxin-induced inflammation down-regulates L-type amino acid transporter 1 (LAT1) expression at the blood-brain barrier of male rats and mice. Fluids Barriers CNS 2015; 12:21. [PMID: 26337286 PMCID: PMC4559167 DOI: 10.1186/s12987-015-0016-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 08/18/2015] [Indexed: 11/13/2022] Open
Abstract
Background We recently reported that bacterial lipopolysaccharide (LPS)-induced inflammation decreases the expression of the primary thyroid hormone transporters at the blood–brain barrier, organic anion-transporting polypeptide 1c1 (OATP1c1) and monocarboxylate transporter 8 (MCT8). l-type amino acid transporters 1 and 2 (LAT1 & LAT2) are regarded as secondary thyroid hormone transporters, and are expressed in cells of the blood–brain or blood-cerebrospinal fluid barrier and by neurons. The purpose of this study was to examine the effect of LPS-induced inflammation on the expression of LAT1 and LAT2, as these may compensate for the downregulation of OATP1c1 and MCT8. Methods LPS (2.5 mg/kg body weight) was injected intraperitoneally to adult, male, Sprague–Dawley rats and C57Bl/6 mice, which were euthanized 2, 4, 9, 24 or 48 h later. LAT1 and LAT2 mRNA expression were studied on forebrain sections using semiquantitative radioactive in situ hybridization. LAT1 protein levels in brain vessels were studied using LAT1 immunofluorescence. Statistical comparisons were made by the non-parametric Kruskal–Wallis and Dunn’s tests. Results In both species, LAT1 mRNA decreased in brain blood vessels as soon as 2 h after LPS injection and was virtually undetectable at 4 h and 9 h. During recovery from endotoxemia, 48 h after LPS injection, LAT1 mRNA in brain vessels increased above control levels. A modest but significant decrease in LAT1 protein levels was detected in the brain vessels of mice at 24 h following LPS injection. LPS did not affect LAT1 and LAT2 mRNA expression in neurons and choroid plexus epithelial cells. Conclusions The results demonstrate that LPS-induced inflammation rapidly decreases LAT1 mRNA expression at the blood–brain barrier in a very similar manner to primary thyroid hormone transporters, while changes in LAT1 protein level follow a slower kinetics. The data raise the possibility that inflammation may similarly down-regulate other blood–brain barrier transport systems at the transcriptional level. Future studies are required to examine this possibility and the potential pathophysiological consequences of inflammation-induced changes in blood–brain barrier transport functions. Electronic supplementary material The online version of this article (doi:10.1186/s12987-015-0016-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Gábor Wittmann
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, Tupper Research Institute, Tufts Medical Center, Boston, MA, USA.
| | - Petra Mohácsik
- Department of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary. .,Semmelweis University, János Szentágothai PhD School of Neurosciences, Budapest, Hungary.
| | - Mumtaz Yaseen Balkhi
- Division of Hematology/Oncology, Department of Medicine, Tupper Research Institute, Tufts Medical Center, Boston, MA, USA.
| | - Balázs Gereben
- Department of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary.
| | - Ronald M Lechan
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, Tupper Research Institute, Tufts Medical Center, Boston, MA, USA. .,Department of Neuroscience, Tufts University School of Medicine, Boston, MA, USA.
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