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Di Cosmo C, De Marco G, Agretti P, Ferrarini E, Dimida A, Falcetta P, Benvenga S, Vitti P, Tonacchera M. Screening for drugs potentially interfering with MCT8-mediated T 3 transport in vitro identifies dexamethasone and some commonly used drugs as inhibitors of MCT8 activity. J Endocrinol Invest 2022; 45:803-814. [PMID: 34850364 DOI: 10.1007/s40618-021-01711-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 11/19/2021] [Indexed: 12/19/2022]
Abstract
BACKGROUND Monocarboxylate transporter 8 (MCT8) is the first thyroid hormone transporter that has been linked to a human disease. Besides genetic alterations other factors might impair MCT8 activity. AIM This study aimed at investigating whether some common drugs having a structural similarity with TH and/or whose treatment is associated with thyroid function test abnormalities, or which behave as antagonists of TH action can inhibit MCT8-mediated T3 transport. METHODS [125I]T3 uptake and efflux were measured in COS-7 cells transiently transfected with hMCT8 before and after exposure to increasing concentrations of hydrocortisone, dexamethasone, prednisone, prednisolone, amiodarone, desethylamiodarone, dronedarone, buspirone, carbamazepine, valproic acid, and L-carnitine. The mode of inhibition was also determined. RESULTS Dexamethasone significantly inhibited T3 uptake at 10 μM; hydrocortisone reduced T3 uptake only at high concentrations, i.e. at 500 and 1000 μM; prednisone and prednisolone were devoid of inhibitory potential. Amiodarone caused a reduction of T3 uptake by MCT8 only at the highest concentrations used (44% at 50 μM and 68% at 100 μM), and this effect was weaker than that produced by desethylamiodarone and dronedarone; buspirone resulted a potent inhibitor, reducing T3 uptake at 0.1-10 μM. L-Carnitine inhibited T3 uptake only at 500 mM and 1 M. Kinetic experiments revealed a noncompetitive mode of inhibition for all compounds. All drugs inhibiting T3 uptake did not affect T3 release. CONCLUSION This study shows a novel effect of some common drugs, which is inhibition of T3 transport mediated by MCT8. Specifically, dexamethasone, buspirone, desethylamiodarone, and dronedarone behave as potent inhibitors of MCT8.
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Affiliation(s)
- C Di Cosmo
- Department of Clinical and Experimental Medicine, Endocrinology Unit, University of Pisa, via Paradisa 2, 56124, Pisa, Italy.
| | - G De Marco
- Department of Clinical and Experimental Medicine, Endocrinology Unit, University of Pisa, via Paradisa 2, 56124, Pisa, Italy
| | - P Agretti
- Laboratory of Chemistry and Endocrinology, University Hospital of Pisa, Pisa, Italy
| | - E Ferrarini
- Department of Clinical and Experimental Medicine, Endocrinology Unit, University of Pisa, via Paradisa 2, 56124, Pisa, Italy
| | - A Dimida
- Department of Clinical and Experimental Medicine, Endocrinology Unit, University of Pisa, via Paradisa 2, 56124, Pisa, Italy
| | - P Falcetta
- Department of Clinical and Experimental Medicine, Endocrinology Unit, University of Pisa, via Paradisa 2, 56124, Pisa, Italy
| | - S Benvenga
- Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy
| | - P Vitti
- Department of Clinical and Experimental Medicine, Endocrinology Unit, University of Pisa, via Paradisa 2, 56124, Pisa, Italy
| | - M Tonacchera
- Department of Clinical and Experimental Medicine, Endocrinology Unit, University of Pisa, via Paradisa 2, 56124, Pisa, Italy
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Bernal Barquero CE, Martín M, Geysels RC, Peyret V, Papendieck P, Masini-Repiso AM, Chiesa AE, Nicola JP. An Intramolecular Ionic Interaction Linking Defective Sodium/Iodide Symporter Transport to the Plasma Membrane and Dyshormonogenic Congenital Hypothyroidism. Thyroid 2022; 32:19-27. [PMID: 34726525 DOI: 10.1089/thy.2021.0344] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Background: The sodium/iodide symporter (NIS) mediates active iodide accumulation in the thyroid follicular cell. Autosomal recessive iodide transport defect (ITD)-causing loss-of-function NIS variants lead to dyshormonogenic congenital hypothyroidism due to deficient iodide accumulation for thyroid hormonogenesis. Here, we aimed to identify, and if so to functionally characterize, novel ITD-causing NIS pathogenic variants in a patient diagnosed with severe dyshormonogenic congenital hypothyroidism due to a defect in iodide accumulation in the thyroid follicular cell, as suggested by nondetectable radioiodide accumulation in a normally located thyroid gland, as well as in salivary glands. Methods: The proposita NIS-coding SLC5A5 gene was sequenced using Sanger sequencing. In silico analysis and functional in vitro characterization of the novel NIS variants were performed. Results: Sanger sequencing revealed novel compound heterozygous SLC5A5 gene variants (c.970-3C>A and c.1106A>T, p.D369V). In silico analysis suggested that c.970-3C>A disrupts the canonical splice acceptor site located in intron 7. Splicing minigene reporter assay revealed that c.970-3C>A causes exon 8 skipping during NIS pre-mRNA splicing leading to the NIS pathogenic variant p.Y324Hfs*148. Moreover, in silico analysis indicated p.D369V as pathogenic. Functional in vitro studies demonstrated that p.D369V NIS does not mediate iodide accumulation, as p.D369V causes NIS to be retained in the endoplasmic reticulum. Mechanistically, we propose an intramolecular ionic interaction involving the β carboxyl group of D369 and the guanidinium group of R130, located in transmembrane segment 4. Of note, an Asp residue at position 369-which is highly conserved in SLC5A family members-is required for functional NIS expression at the plasma membrane. Conclusions: We uncovered a critical intramolecular interaction between R130 and D369 required for NIS maturation and plasma membrane expression. Moreover, we identified the first intronic variant causing aberrant NIS pre-mRNA splicing, thus expanding the mutational landscape in the SLC5A5 gene leading to dyshormonogenic congenital hypothyroidism.
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Affiliation(s)
- Carlos Eduardo Bernal Barquero
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
- Centro de Investigaciones en Bioquímica Clínica e Inmunología-Consejo Nacional de Investigaciones Científicas y Técnicas (CIBICI-CONICET), Córdoba, Argentina
| | - Mariano Martín
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
- Centro de Investigaciones en Bioquímica Clínica e Inmunología-Consejo Nacional de Investigaciones Científicas y Técnicas (CIBICI-CONICET), Córdoba, Argentina
| | - Romina Celeste Geysels
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
- Centro de Investigaciones en Bioquímica Clínica e Inmunología-Consejo Nacional de Investigaciones Científicas y Técnicas (CIBICI-CONICET), Córdoba, Argentina
| | - Victoria Peyret
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
- Centro de Investigaciones en Bioquímica Clínica e Inmunología-Consejo Nacional de Investigaciones Científicas y Técnicas (CIBICI-CONICET), Córdoba, Argentina
| | - Patricia Papendieck
- División de Endocrinología, Hospital de Niños Dr. Ricardo Gutiérrez, Buenos Aires, Argentina
- Centro de Investigaciones Endocrinológicas Dr. César Bergadá-Consejo Nacional de Investigaciones Científicas y Técnicas (CEDIE-CONICET), Buenos Aires, Argentina
| | - Ana María Masini-Repiso
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
- Centro de Investigaciones en Bioquímica Clínica e Inmunología-Consejo Nacional de Investigaciones Científicas y Técnicas (CIBICI-CONICET), Córdoba, Argentina
| | - Ana Elena Chiesa
- División de Endocrinología, Hospital de Niños Dr. Ricardo Gutiérrez, Buenos Aires, Argentina
- Centro de Investigaciones Endocrinológicas Dr. César Bergadá-Consejo Nacional de Investigaciones Científicas y Técnicas (CEDIE-CONICET), Buenos Aires, Argentina
| | - Juan Pablo Nicola
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
- Centro de Investigaciones en Bioquímica Clínica e Inmunología-Consejo Nacional de Investigaciones Científicas y Técnicas (CIBICI-CONICET), Córdoba, Argentina
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Xie L, Xie Y, Mao G, Cao S, Fang R, Zhou S, Jiang J, Yao T, Fan J, Liu D, Wu D, Ge J. Decreased spasticity of Baishaoluoshi Decoction through the BDNF/TrKB-KCC2 pathway on poststroke spasticity rats. Neuroreport 2021; 32:1183-1191. [PMID: 34284448 PMCID: PMC8389354 DOI: 10.1097/wnr.0000000000001709] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 06/11/2021] [Indexed: 01/02/2023]
Abstract
OBJECTIVE K+-Cl- cotransporter-2 (KCC2), which primarily extrudes chloride in mature neurons, triggers hemiplegia limb spasticity after ischemic stroke by affecting neuronal excitability. Our previous study revealed that the Chinese herb Baishaoluoshi Decoction decreases hemiplegia limb spasticity in poststroke spasticity (PSS) patients. This study aimed at elucidating on the effects of Baishaoluoshi Decoction on the BDNF/TrKB-KCC2 pathway in PSS rat models. METHODS Middle cerebral artery occlusion (MCAO) was adopted for the establishment of PSS rat models. Muscle tension was evaluated by Modified Ashworth Scale. Nissl staining and transmission electron microscopy were used to measure the protective effects of Baishaoluoshi Decoction on ischemic injury-induced neuronal damage due to MCAO. Expression levels of BDNF, TrKB, and KCC2 in brain tissues around the infarct and brainstem were detected by immunohistochemical staining. RESULTS It was found that Baishaoluoshi Decoction suppressed hemiplegia limb spasticity and alleviated the damage in neurons and synapses in PSS rat models. Importantly, the expression of BDNF, TrKB, and KCC2 in brain tissues around the infarct and brainstem were significantly upregulated after treatment with low-dose and high-dose Baishaoluoshi Decoction. CONCLUSION Suppression of spasticity by Baishaoluoshi Decoction in PSS rat models may be correlated with upregulated BDNF/TrKB-KCC2 pathway, which may be a complementary therapeutic strategy for PSS.
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Affiliation(s)
- Le Xie
- Neurology Department, Hunan Academy of Chinese Medicine Affiliated Hospital
| | - Yao Xie
- Neurology Department, Hunan Academy of Chinese Medicine Affiliated Hospital
| | - Guo Mao
- Neurology Department, Hunan Academy of Chinese Medicine Affiliated Hospital
| | - Sijia Cao
- Foreign Languages Department, School of Humanities and Management, Hunan University of Chinese Medicine
| | - Rui Fang
- Chinese Pharmacy Teaching and Research Department, College of Integrated Traditional Chinese and Western Medicine, Hunan University of Chinese Medicine, Changsha, Hunan
| | - Shen Zhou
- Neurology Department, Hunan Academy of Chinese Medicine Affiliated Hospital
| | - Junlin Jiang
- Neurology Department, Hunan Academy of Chinese Medicine Affiliated Hospital
| | - Ting Yao
- Neurology Department, Hunan Academy of Chinese Medicine Affiliated Hospital
| | - Jianhu Fan
- Neurology Department, Hunan Academy of Chinese Medicine Affiliated Hospital
| | - Dong Liu
- Hunan Key Laboratory of Prevention and Treatment in Cardiovascular Disease, College of Pharmacy, Guiyang University of Chinese Medicine, Guiyang, Guizhou, China
| | - Dahua Wu
- Neurology Department, Hunan Academy of Chinese Medicine Affiliated Hospital
| | - Jinwen Ge
- Chinese Pharmacy Teaching and Research Department, College of Integrated Traditional Chinese and Western Medicine, Hunan University of Chinese Medicine, Changsha, Hunan
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Zarepour L, Gharaylou Z, Hadjighassem M, Shafaghi L, Majedi H, Behzad E, Hosseindoost S, Ramezani F, Nasirinezhad F. Preliminary study of analgesic effect of bumetanide on neuropathic pain in patients with spinal cord injury. J Clin Neurosci 2020; 81:477-484. [PMID: 33222966 DOI: 10.1016/j.jocn.2020.10.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 09/07/2020] [Accepted: 10/03/2020] [Indexed: 02/01/2023]
Abstract
BACKGROUND/OBJECTIVE The current study evaluated the analgesic effects of bumetanide as an adjunctive treatment in managing neuropathic pain following spinal cord injury. The peripheral expression level of Na-K-Cl-cotransporter-1 (NKCC1) and K-Cl-cotransporter-2 (KCC2) genes in polymorphonuclear lymphocytes (PMLs) assessed as a possible biomarker indicating central underlying mechanisms. METHODS This open-label, single-arm, pilot trial of bumetanide (2 mg/day) is an add-on treatment conducted in 14 SCI patients for 19 weeks. The whole duration consisted of three phases: pre-treatment (1 month), titration (3 weeks), and active treatment (4 months). Ultimately, nine patients completed the study. The primary outcome variables were the endpoint pain score measured by the numeric rating scale (NRS), and the short-form McGill Pain Questionnaire. Secondary endpoints included the Short-Form Health Survey that measures the quality of life. Blood samples were collected and used for determining the expression of NKCC1 and KCC2 genes in transcription and translation levels. RESULTS Bumetanide treatment significantly reduced average pain intensity according to the NRS and the short form of the McGill Pain Questionnaire scores. The baseline expression of KCC2 protein was low between groups and increased significantly following treatment (P < 0.05). Through the current study, pain improvement accompanied by the more significant mean change from the baseline for the overall quality of life. CONCLUSION These data might be a piece of preliminary evidence for the analgesic effect of bumetanide on neuropathic pain and could support the potential role of the upregulation of KCC2 protein and involvement of GABAergic disinhibition in producing neuropathic pain.
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Affiliation(s)
- Leila Zarepour
- Department of Physiology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Zeinab Gharaylou
- Multiple Sclerosis Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Mahmoudreza Hadjighassem
- Department of Neuroscience and Addiction Studies, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran; Brain and Spinal Cord Injury Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran.
| | - Lida Shafaghi
- Department of Neuroscience and Addiction Studies, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Hossein Majedi
- Brain and Spinal Cord Injury Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Ebrahim Behzad
- Department of Neuroscience and Addiction Studies, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Saereh Hosseindoost
- Department of Neuroscience and Addiction Studies, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Fatemeh Ramezani
- Department of Physiology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Farinaz Nasirinezhad
- Department of Physiology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
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Lisco G, De Tullio A, Giagulli VA, De Pergola G, Triggiani V. Interference on Iodine Uptake and Human Thyroid Function by Perchlorate-Contaminated Water and Food. Nutrients 2020; 12:nu12061669. [PMID: 32512711 PMCID: PMC7352877 DOI: 10.3390/nu12061669] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 05/31/2020] [Accepted: 06/01/2020] [Indexed: 12/12/2022] Open
Abstract
Background: Perchlorate-induced natrium-iodide symporter (NIS) interference is a well-recognized thyroid disrupting mechanism. It is unclear, however, whether a chronic low-dose exposure to perchlorate delivered by food and drinks may cause thyroid dysfunction in the long term. Thus, the aim of this review was to overview and summarize literature results in order to clarify this issue. Methods: Authors searched PubMed/MEDLINE, Scopus, Web of Science, institutional websites and Google until April 2020 for relevant information about the fundamental mechanism of the thyroid NIS interference induced by orally consumed perchlorate compounds and its clinical consequences. Results: Food and drinking water should be considered relevant sources of perchlorate. Despite some controversies, cross-sectional studies demonstrated that perchlorate exposure affects thyroid hormone synthesis in infants, adolescents and adults, particularly in the case of underlying thyroid diseases and iodine insufficiency. An exaggerated exposure to perchlorate during pregnancy leads to a worse neurocognitive and behavioral development outcome in infants, regardless of maternal thyroid hormone levels. Discussion and conclusion: The effects of a chronic low-dose perchlorate exposure on thyroid homeostasis remain still unclear, leading to concerns especially for highly sensitive patients. Specific studies are needed to clarify this issue, aiming to better define strategies of detection and prevention.
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Affiliation(s)
- Giuseppe Lisco
- ASL Brindisi, Unit of Endocrinology, Metabolism & Clinical Nutrition, Hospital “A. Perrino”, Strada per Mesagne 7, 72100 Brindisi, Puglia, Italy;
| | - Anna De Tullio
- Interdisciplinary Department of Medicine—Section of Internal Medicine, Geriatrics, Endocrinology and Rare Diseases, University of Bari “Aldo Moro”, School of Medicine, Policlinico, Piazza Giulio Cesare 11, 70124 Bari, Puglia, Italy; (A.D.T.); (V.A.G.)
| | - Vito Angelo Giagulli
- Interdisciplinary Department of Medicine—Section of Internal Medicine, Geriatrics, Endocrinology and Rare Diseases, University of Bari “Aldo Moro”, School of Medicine, Policlinico, Piazza Giulio Cesare 11, 70124 Bari, Puglia, Italy; (A.D.T.); (V.A.G.)
- Clinic of Endocrinology and Metabolic Disease, Conversano Hospital, Via Edmondo de Amicis 36, 70014 Conversano, Bari, Puglia, Italy
| | - Giovanni De Pergola
- Department of Biomedical Sciences and Human Oncology, Section of Internal Medicine and Clinical Oncology, University of Bari Aldo Moro, Piazza Giulio Cesare 11, 70124 Bari, Puglia, Italy;
| | - Vincenzo Triggiani
- Interdisciplinary Department of Medicine—Section of Internal Medicine, Geriatrics, Endocrinology and Rare Diseases, University of Bari “Aldo Moro”, School of Medicine, Policlinico, Piazza Giulio Cesare 11, 70124 Bari, Puglia, Italy; (A.D.T.); (V.A.G.)
- Correspondence:
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Oppedisano F, Muscoli C, Musolino V, Carresi C, Macrì R, Giancotta C, Bosco F, Maiuolo J, Scarano F, Paone S, Nucera S, Zito MC, Scicchitano M, Ruga S, Ragusa M, Palma E, Tavernese A, Mollace R, Bombardelli E, Mollace V. The Protective Effect of Cynara Cardunculus Extract in Diet-Induced NAFLD: Involvement of OCTN1 and OCTN2 Transporter Subfamily. Nutrients 2020; 12:E1435. [PMID: 32429274 PMCID: PMC7284543 DOI: 10.3390/nu12051435] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 05/05/2020] [Accepted: 05/08/2020] [Indexed: 12/12/2022] Open
Abstract
Hyperlipidemia and insulin-resistance are often associated with Non-Alcoholic Fatty Liver Disease (NAFLD) thereby representing a true issue worldwide due to increased risk of developing cardiovascular and systemic disorders. Although clear evidence suggests that circulating fatty acids contribute to pathophysiological mechanisms underlying NAFLD and hyperlipidemia, further studies are required to better identify potential beneficial approaches for counteracting such a disease. Recently, several artichoke extracts have been used for both reducing hyperlipidemia, insulin-resistance and NAFLD, though the mechanism is unclear. Here we used a wild type of Cynara Cardunculus extract (CyC), rich in sesquiterpens and antioxidant active ingredients, in rats fed a High Fat Diet (HFD) compared to a Normal Fat Diet (NFD). In particular, in rats fed HFD for four consecutive weeks, we found a significant increase of serum cholesterol, triglyceride and serum glucose. This effect was accompanied by increased body weight and by histopathological features of liver steatosis. The alterations of metabolic parameters found in HFDs were antagonised dose-dependently by daily oral supplementation of rats with CyC 10 and 20 mg/kg over four weeks, an effect associated to significant improvement of liver steatosis. The effect of CyC (20 mg/kg) was also associated to enhanced expression of both OCTN1 and OCTN2 carnitine-linked transporters. Thus, present data suggest a contribution of carnitine system in the protective effect of CyC in diet-induced hyperlipidemia, insulin-resistance and NAFLD.
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Affiliation(s)
- Francesca Oppedisano
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Carolina Muscoli
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
- San Raffaele IRCCS, 00199 Rome, Italy
| | - Vincenzo Musolino
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Cristina Carresi
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Roberta Macrì
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Caterina Giancotta
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Francesca Bosco
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Jessica Maiuolo
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Federica Scarano
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Sara Paone
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Saverio Nucera
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Maria Caterina Zito
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Miriam Scicchitano
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Stefano Ruga
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Monica Ragusa
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Ernesto Palma
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Annamaria Tavernese
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Rocco Mollace
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Ezio Bombardelli
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Vincenzo Mollace
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
- San Raffaele IRCCS, 00199 Rome, Italy
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7
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Abstract
Advancing therapeutics for traumatic brain injury (TBI) remains a challenge, necessitating testable targets with interventions appropriately timed to intercede on evolving secondary insults. Neuroproteomics provides a global molecular approach to deduce the complex post-translational processes that underlie secondary events after TBI. Yet method advancement has outpaced approaches to interrogate neuroproteomic complexity, in particular when addressing the well-recognized temporal evolution of TBI pathobiology. Presented is a detailed account of the temporal neuroproteomic response to mild-moderate rat controlled cortical impact within perilesioned somatosensory neocortex across the first two weeks after injury. Further, this investigation assessed use of artificial neural network and functional enrichment analyses to discretize the temporal response across some 2047 significantly impacted proteins. Results were efficiently narrowed onto ion transporters with phenotypic relevance to abnormal GABAergic transmission and a delayed decline amenable to intervention under managed care conditions. The prototypical target potassium/chloride co-transporter 2 (KCC2 or SLC12A5) was investigated further with the KCC2-selective modulator CLP290. Guided by post-translational processing revealed one-day after insult to precede KCC2 protein loss a day after, CLP290 was highly effective at restoring up to 70% of lost KCC2 localization, which was significantly correlated with recovery of sham-level function in assessed somatosensory behavioral tasks. The timing of administration was important, with no significant improvement observed if given earlier, one-hour after insult, or later when KCC2 protein decline begins. Results portend importance for a detailed post-translational characterization when devising TBI treatments, and support the therapeutic promise of KCC2-targeted CLP290 intervention for positive functional recovery after brain injury.
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Affiliation(s)
- Pavel N. Lizhnyak
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, Virginia
| | - Pretal P. Muldoon
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, Virginia
| | - Pallavi P. Pilaka
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, Virginia
| | - John T. Povlishock
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, Virginia
| | - Andrew K. Ottens
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, Virginia
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8
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Kharod SC, Carter BM, Kadam SD. Pharmaco-resistant Neonatal Seizures: Critical Mechanistic Insights from a Chemoconvulsant Model. Dev Neurobiol 2018; 78:1117-1130. [PMID: 30136373 PMCID: PMC6214781 DOI: 10.1002/dneu.22634] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 07/10/2018] [Accepted: 07/24/2018] [Indexed: 12/18/2022]
Abstract
Neonatal seizures are harmful to the developing brain and are associated with mortality and long-term neurological comorbidities. Hypoxic-ischemic encephalopathy (HIE) seizures represent a significant proportion of such seizures. Phenobarbital (PB) remains the first line anti-seizure drug (ASD) treatment but fails ~50% of the time. Translational models of neonatal seizures are crucial to investigating mechanisms underlying PB-resistance. A model of PB-resistant ischemic seizures in postnatal day 7 (P7) CD-1 mice reported K-Cl cotransporter 2 (KCC2) degradation that has been shown to be due to activation of the TrkB pathway. We investigated PB-efficacy in a pentylenetetrazole (PTZ) model of neonatal seizures in the same strain and age using identical treatment protocols to gain insights into mechanisms underlying PB-resistance. A single dose of PTZ (80 mg/kg; IP) consistently induced repetitive seizures that did not progress to status epilepticus (SE). PB (25 mg/kg; IP, single dose) significantly suppressed the PTZ-induced seizures. This was associated with significant KCC2 upregulation and stable Na-K-Cl cotransporter 1 (NKCC1) expression at 24h. The TrkB pathway was not activated. PTZ seizure burdens were significantly higher than those reported for ischemic seizures, indicating seizure severity did not dictate the differences in PB-efficacy. Bumetanide (BTN) (0.1-0.2 mg/kg; IP) did not work as an anti-seizure agent, similar to the ischemic model. When investigating mechanisms underlying the emergence of PB-resistance in translational models, the method by which seizures are induced may dictate mechanisms underlying emergence of PB-resistance.
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Affiliation(s)
- Shivani C. Kharod
- Neuroscience Laboratory, Johns Hopkins University School of Medicine; Baltimore, MD 21205
| | - Brandon M. Carter
- Neuroscience Laboratory, Johns Hopkins University School of Medicine; Baltimore, MD 21205
| | - Shilpa D. Kadam
- Neuroscience Laboratory, Johns Hopkins University School of Medicine; Baltimore, MD 21205
- Hugo Moser Research Institute at Kennedy Krieger; Department of Neurology, Johns Hopkins University School of Medicine; Baltimore, MD 21205
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9
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Yang CY, Liu SY, Wang HY, Li YL, Guo D, Wang XY, Hua W, Wang GL. Neuroprotection by Propofol Post-Conditioning: Focus on PKMζ/KCC2 Pathway Activity. Cell Mol Neurobiol 2018; 38:691-701. [PMID: 28779332 DOI: 10.1007/s10571-017-0530-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2017] [Accepted: 07/31/2017] [Indexed: 12/11/2022]
Abstract
Critical and major operations are often accompanied by brain ischemic complications. Previous studies found that propofol post-conditioning provided neuroprotective functions through upregulating the expression of potassium chloride cotransporter 2 (KCC2) in gamma-aminobutyric acid (GABA) interneurons. Membrane expression and phosphorylation represents KCC2 activity, which were modulated by a protein kinase C (PKC)-dependent mechanism. However, the role of propofol in increasing KCC2 phosphorylation and the involvement of protein kinase Mζ (PKMζ), a major subtype of PKC, in the KCC2 pathway remained unclear. In this study, we established middle cerebral artery occlusion model in rats to evaluate the long-term recovery of brain functions using behavioral experiments. KCC2 and PKMζ were assessed via western blot. We used the selective inhibitor, zeta inhibitory peptide (ZIP), to investigate the relationship between KCC2 and PKMζ. Intracellular chloride concentration in the hippocampal CA1 area was measured to determine KCC2 activity. We found that propofol, infused at a speed of 20 mg kg-1 h-1 for 2 h at the onset of reperfusion, improved neurological deficits and cognitive dysfunction following ischemia/reperfusion injury. PKMζ expression was significantly upregulated, which improved KCC2 membrane expression and phosphorylation in the ischemic hippocampal CA1 area, and these effects could last up to 28 days. But ZIP inhibited this process. Ultimately, we showed that propofol increased KCC2 phosphorylation and PKMζ was the upstream of KCC2. Propofol led to long-term recovery of brain functions by upregulating the activity of the PKMζ/KCC2 pathway.
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Affiliation(s)
- Chen-Yi Yang
- Department of Anesthesiology, Tianjin Third Central Hospital, Third Central Clinical College of Tianjin Medical University, Tianjin Key Laboratory of Artificial Cell, Artificial Cell Engineering Research Centre of the Ministry of Health, Tianjin, 300170, China
| | - Shu-Ying Liu
- Department of Anesthesiology, Tianjin Third Central Hospital, Third Central Clinical College of Tianjin Medical University, Tianjin Key Laboratory of Artificial Cell, Artificial Cell Engineering Research Centre of the Ministry of Health, Tianjin, 300170, China
| | - Hai-Yun Wang
- Department of Anesthesiology, Tianjin Third Central Hospital, Third Central Clinical College of Tianjin Medical University, Tianjin Key Laboratory of Artificial Cell, Artificial Cell Engineering Research Centre of the Ministry of Health, Tianjin, 300170, China.
- Tianjin Research Institute of Anesthesiology, Tianjin Medical University General Hospital, Tianjin, 300052, China.
| | - Yan-Li Li
- Department of Anesthesiology, Tianjin Third Central Hospital, Third Central Clinical College of Tianjin Medical University, Tianjin Key Laboratory of Artificial Cell, Artificial Cell Engineering Research Centre of the Ministry of Health, Tianjin, 300170, China
| | - Di Guo
- Department of Anesthesiology, Tianjin Third Central Hospital, Third Central Clinical College of Tianjin Medical University, Tianjin Key Laboratory of Artificial Cell, Artificial Cell Engineering Research Centre of the Ministry of Health, Tianjin, 300170, China
| | - Xin-Yue Wang
- Department of Anesthesiology, Tianjin Third Central Hospital, Third Central Clinical College of Tianjin Medical University, Tianjin Key Laboratory of Artificial Cell, Artificial Cell Engineering Research Centre of the Ministry of Health, Tianjin, 300170, China
| | - Wei Hua
- Department of Anesthesiology, Tianjin Third Central Hospital, Third Central Clinical College of Tianjin Medical University, Tianjin Key Laboratory of Artificial Cell, Artificial Cell Engineering Research Centre of the Ministry of Health, Tianjin, 300170, China
| | - Guo-Lin Wang
- Tianjin Research Institute of Anesthesiology, Tianjin Medical University General Hospital, Tianjin, 300052, China
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10
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Frenette-Cotton R, Marcoux AA, Garneau AP, Noel M, Isenring P. Phosphoregulation of K + -Cl - cotransporters during cell swelling: Novel insights. J Cell Physiol 2018; 233:396-408. [PMID: 28276587 DOI: 10.1002/jcp.25899] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 03/06/2017] [Indexed: 01/21/2023]
Abstract
The K+ -Cl- cotransporters (KCCs) belong to the cation-Cl- cotransporter family and consist of four isoforms and many splice variants. Their main role is to promote electroneutral efflux of K+ and Cl- ions across the surface of many cell types and, thereby, to regulate intracellular ion concentration, cell volume, and epithelial salt movement. These transport systems are induced by an increase in cell volume and are less active at lower intracellular [Cl- ] (Cli ), but the mechanisms at play are still ill-defined. In this work, we have exploited the Xenopus laevis expression system to study the role of lysine-deficient protein kinases (WNKs), protein phosphatases 1 (PP1s), and SPS1-related proline/alanine-rich kinase (SPAK) in KCC4 regulation during cell swelling. We have found that WNK4 and PP1 regulate KCC4 activity as part of a common signaling module, but that they do not exert their effects through SPAK or carrier dephosphorylation. We have also found that the phosphatases at play include PP1α and PP1γ1, but that WNK4 acts directly on the PP1s instead of the opposite. Unexpectedly, however, both cell swelling and a T926A substitution in the C-terminus of full-length KCC4 led to higher levels of heterologous K+ -Cl- cotransport and overall carrier phosphorylation. These results imply that the response to cell swelling must also involve allosteric-sensitive kinase-dependent phosphoacceptor sites in KCC4. They are thus partially inconsistent with previous models of KCC regulation.
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Affiliation(s)
| | - Andrée-Anne Marcoux
- Nephrology Research Group, Department of Medicine, Laval University, Québec, Québec, Canada
| | - Alexandre P Garneau
- Nephrology Research Group, Department of Medicine, Laval University, Québec, Québec, Canada
| | - Micheline Noel
- Nephrology Research Group, Department of Medicine, Laval University, Québec, Québec, Canada
| | - Paul Isenring
- Nephrology Research Group, Department of Medicine, Laval University, Québec, Québec, Canada
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11
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Liabeuf S, Stuhl-Gourmand L, Gackière F, Mancuso R, Sanchez Brualla I, Marino P, Brocard F, Vinay L. Prochlorperazine Increases KCC2 Function and Reduces Spasticity after Spinal Cord Injury. J Neurotrauma 2017; 34:3397-3406. [PMID: 28747093 DOI: 10.1089/neu.2017.5152] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
In mature neurons, low intracellular chloride level required for inhibition is maintained by the potassium-chloride cotransporter, KCC2. Impairment of Cl- extrusion after KCC2 dysfunction has been involved in many central nervous system disorders, such as seizures, neuropathic pain, or spasticity, after a spinal cord injury (SCI). This makes KCC2 an appealing drug target for restoring Cl- homeostasis and inhibition in pathological conditions. In the present study, we screen the Prestwick Chemical Library® and identify conventional antipsychotics phenothiazine derivatives as enhancers of KCC2 activity. Among them, prochlorperazine hyperpolarizes the Cl- equilibrium potential in motoneurons of neonatal rats and restores the reciprocal inhibition post-SCI. The compound alleviates spasticity in chronic adult SCI rats with an efficacy equivalent to the antispastic agent, baclofen, and rescues the SCI-induced downregulation of KCC2 in motoneurons below the lesion. These pre-clinical data support prochlorperazine for a new therapeutic indication in the treatment of spasticity post-SCI and neurological disorders involving a KCC2 dysfunction.
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Affiliation(s)
- Sylvie Liabeuf
- Team P3M, Institut de Neurosciences de la Timone, UMR7289, Aix Marseille Université and Centre National de la Recherche Scientifique (CNRS) , Marseille, France
| | - Laetitia Stuhl-Gourmand
- Team P3M, Institut de Neurosciences de la Timone, UMR7289, Aix Marseille Université and Centre National de la Recherche Scientifique (CNRS) , Marseille, France
| | - Florian Gackière
- Team P3M, Institut de Neurosciences de la Timone, UMR7289, Aix Marseille Université and Centre National de la Recherche Scientifique (CNRS) , Marseille, France
| | - Renzo Mancuso
- Team P3M, Institut de Neurosciences de la Timone, UMR7289, Aix Marseille Université and Centre National de la Recherche Scientifique (CNRS) , Marseille, France
| | - Irene Sanchez Brualla
- Team P3M, Institut de Neurosciences de la Timone, UMR7289, Aix Marseille Université and Centre National de la Recherche Scientifique (CNRS) , Marseille, France
| | - Philippe Marino
- Team P3M, Institut de Neurosciences de la Timone, UMR7289, Aix Marseille Université and Centre National de la Recherche Scientifique (CNRS) , Marseille, France
| | - Frédéric Brocard
- Team P3M, Institut de Neurosciences de la Timone, UMR7289, Aix Marseille Université and Centre National de la Recherche Scientifique (CNRS) , Marseille, France
| | - Laurent Vinay
- Team P3M, Institut de Neurosciences de la Timone, UMR7289, Aix Marseille Université and Centre National de la Recherche Scientifique (CNRS) , Marseille, France
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12
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Cardarelli RA, Jones K, Pisella LI, Wobst HJ, McWilliams LJ, Sharpe PM, Burnham MP, Baker DJ, Chudotvorova I, Guyot J, Silayeva L, Morrow DH, Dekker N, Zicha S, Davies PA, Holenz J, Duggan ME, Dunlop J, Mather RJ, Wang Q, Medina I, Brandon NJ, Deeb TZ, Moss SJ. The small molecule CLP257 does not modify activity of the K +-Cl - co-transporter KCC2 but does potentiate GABA A receptor activity. Nat Med 2017; 23:1394-1396. [PMID: 29216042 PMCID: PMC7371006 DOI: 10.1038/nm.4442] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Ross A Cardarelli
- AstraZeneca Tufts Laboratory for Basic and Translational Neuroscience, Boston, Massachusetts, USA
| | - Karen Jones
- Discovery Sciences, IMED Biotech Unit, AstraZeneca, Alderley Park, UK
| | - Lucie I Pisella
- INMED, INSERM, Unité 901, Marseille, France
- Aix-Marseille Université, UMR 901, Marseille, France
| | - Heike J Wobst
- AstraZeneca Tufts Laboratory for Basic and Translational Neuroscience, Boston, Massachusetts, USA
- Neuroscience, IMED Biotech Unit, AstraZeneca, Boston, Massachusetts, USA
| | | | - Paul M Sharpe
- Discovery Sciences, IMED Biotech Unit, AstraZeneca, Alderley Park, UK
| | - Matthew P Burnham
- Discovery Sciences, IMED Biotech Unit, AstraZeneca, Alderley Park, UK
| | - David J Baker
- Discovery Sciences, IMED Biotech Unit, AstraZeneca, Cambridge, UK
| | - Ilona Chudotvorova
- INMED, INSERM, Unité 901, Marseille, France
- Aix-Marseille Université, UMR 901, Marseille, France
| | - Justine Guyot
- INMED, INSERM, Unité 901, Marseille, France
- Aix-Marseille Université, UMR 901, Marseille, France
| | - Liliya Silayeva
- AstraZeneca Tufts Laboratory for Basic and Translational Neuroscience, Boston, Massachusetts, USA
| | - Danielle H Morrow
- Department of Neuroscience, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - Niek Dekker
- Discovery Sciences, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Stephen Zicha
- Neuroscience, IMED Biotech Unit, AstraZeneca, Boston, Massachusetts, USA
| | - Paul A Davies
- Department of Neuroscience, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - Jörg Holenz
- Neuroscience, IMED Biotech Unit, AstraZeneca, Boston, Massachusetts, USA
| | - Mark E Duggan
- Neuroscience, IMED Biotech Unit, AstraZeneca, Boston, Massachusetts, USA
| | - John Dunlop
- Neuroscience, IMED Biotech Unit, AstraZeneca, Boston, Massachusetts, USA
| | - Robert J Mather
- Neuroscience, IMED Biotech Unit, AstraZeneca, Boston, Massachusetts, USA
| | - Qi Wang
- AstraZeneca Tufts Laboratory for Basic and Translational Neuroscience, Boston, Massachusetts, USA
- Neuroscience, IMED Biotech Unit, AstraZeneca, Boston, Massachusetts, USA
| | - Igor Medina
- INMED, INSERM, Unité 901, Marseille, France
- Aix-Marseille Université, UMR 901, Marseille, France
| | - Nicholas J Brandon
- AstraZeneca Tufts Laboratory for Basic and Translational Neuroscience, Boston, Massachusetts, USA
- Neuroscience, IMED Biotech Unit, AstraZeneca, Boston, Massachusetts, USA
| | - Tarek Z Deeb
- AstraZeneca Tufts Laboratory for Basic and Translational Neuroscience, Boston, Massachusetts, USA
| | - Stephen J Moss
- AstraZeneca Tufts Laboratory for Basic and Translational Neuroscience, Boston, Massachusetts, USA
- Department of Neuroscience, Tufts University School of Medicine, Boston, Massachusetts, USA
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, UK
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13
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Silvestre de Ferron B, Vilpoux C, Kervern M, Robert A, Antol J, Naassila M, Pierrefiche O. Increase of KCC2 in hippocampal synaptic plasticity disturbances after perinatal ethanol exposure. Addict Biol 2017; 22:1870-1882. [PMID: 27778437 DOI: 10.1111/adb.12465] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 09/13/2016] [Accepted: 09/26/2016] [Indexed: 11/28/2022]
Abstract
Low to moderate perinatal ethanol exposure (PEE) may have disastrous consequences for the central nervous system resulting notably in permanent cognitive deficits. Learning and memory are mediated in the hippocampus by long-term potentiation (LTP) and long term depression (LTD), two forms of synaptic plasticity. PEE decreases LTP but also abnormally facilitates LTD (Kervern et al. ) through a presently unknown mechanism. We studied in rat hippocampus slice, the involvement of the chloride co-transporters NKCC1 and KCC2, in the role of GABAA inhibitions in facilitated LTD after moderate PEE. After PEE and in contrast to control slices, facilitated LTD in CA1 field was reduced by the GABAA receptor antagonist bicuculline with no changes in sensitivity to bicuculline and in GABA and benzodiazepine binding sites. Also, sensitivity to diazepam was unaltered, whereas aberrant LTD was blocked. Immunohistochemistry and protein analysis demonstrated an increase in KCC2 protein level at cell membrane in CA1 after PEE with no change in NKCC1 expression. Specifically, both monomeric and dimeric forms of KCC2 were increased in CA1. Bumetanide (10-100 μM), a dose-dependent blocker of NKCC1 and KCC2, or VU0240551 (10 μM) a specific antagonist of KCC2, corrected the enhanced LTD and interestingly bumetanide also restored the lower LTP after PEE. These results demonstrate for the first time an upregulation of the KCC2 co-transporter expression after moderate PEE associated with disturbances in GABAergic neurotransmission modulating bidirectional synaptic plasticity in the hippocampus. Importantly, bumetanide compensated deficits in both LTP and LTD, revealing its potential therapeutic properties.
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Affiliation(s)
- Benoît Silvestre de Ferron
- INSERM ERI-24, GRAP, Groupe de Recherche sur l'Alcool et les Pharmacodépendances, Centre Universitaire de Recherche en Santé CHU-Sud, Université Picardie Jules Verne, Amiens, France
| | - Catherine Vilpoux
- INSERM ERI-24, GRAP, Groupe de Recherche sur l'Alcool et les Pharmacodépendances, Centre Universitaire de Recherche en Santé CHU-Sud, Université Picardie Jules Verne, Amiens, France
| | - Myriam Kervern
- INSERM ERI-24, GRAP, Groupe de Recherche sur l'Alcool et les Pharmacodépendances, Centre Universitaire de Recherche en Santé CHU-Sud, Université Picardie Jules Verne, Amiens, France
| | - Alexandre Robert
- INSERM ERI-24, GRAP, Groupe de Recherche sur l'Alcool et les Pharmacodépendances, Centre Universitaire de Recherche en Santé CHU-Sud, Université Picardie Jules Verne, Amiens, France
| | - Johan Antol
- INSERM ERI-24, GRAP, Groupe de Recherche sur l'Alcool et les Pharmacodépendances, Centre Universitaire de Recherche en Santé CHU-Sud, Université Picardie Jules Verne, Amiens, France
| | - Mickael Naassila
- INSERM ERI-24, GRAP, Groupe de Recherche sur l'Alcool et les Pharmacodépendances, Centre Universitaire de Recherche en Santé CHU-Sud, Université Picardie Jules Verne, Amiens, France
| | - Olivier Pierrefiche
- INSERM ERI-24, GRAP, Groupe de Recherche sur l'Alcool et les Pharmacodépendances, Centre Universitaire de Recherche en Santé CHU-Sud, Université Picardie Jules Verne, Amiens, France
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14
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Krieger CC, Perry JD, Morgan SJ, Kahaly GJ, Gershengorn MC. TSH/IGF-1 Receptor Cross-Talk Rapidly Activates Extracellular Signal-Regulated Kinases in Multiple Cell Types. Endocrinology 2017; 158:3676-3683. [PMID: 28938449 PMCID: PMC5659693 DOI: 10.1210/en.2017-00528] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 08/08/2017] [Indexed: 12/25/2022]
Abstract
We previously showed that thyrotropin (TSH)/insulinlike growth factor (IGF)-1 receptor cross-talk appears to be involved in Graves' orbitopathy (GO) pathogenesis and upregulation of thyroid-specific genes in human thyrocytes. In orbital fibroblasts from GO patients, coadministration of TSH and IGF-1 induces synergistic increases in hyaluronan secretion. In human thyrocytes, TSH plus IGF-1 synergistically increased expression of the sodium-iodide symporter that appeared to involve ERK1/2 activation. However, the details of ERK1/2 activation were not known, nor was whether ERK1/2 was involved in this synergism in other cell types. Using primary cultures of GO fibroblasts (GOFs) and human thyrocytes, as well as human embryonic kidney (HEK) 293 cells overexpressing TSH receptors (HEK-TSHRs), we show that simultaneous activation of TSHRs and IGF-1 receptors (IGF-1Rs) causes rapid, synergistic phosphorylation/activation of ERK1 and ERK2 in all three cell types. This effect is partially inhibited by pertussis toxin, an inhibitor of TSHR coupling to Gi/Go proteins. In support of a role for Gi/Go proteins in ERK1/2 phosphorylation, we found that knockdown of Gi(1-3) and Go in HEK-TSHRs inhibited ERK1/2 phosphorylation stimulated by TSH and TSH plus IGF-1. These data demonstrate that the synergistic effects of TSH plus IGF-1 occur early in the TSHR signaling cascade and further support the idea that TSHR/IGF-1R cross-talk is an important mechanism for regulation of human GOFs and thyrocytes.
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Affiliation(s)
- Christine C. Krieger
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Joseph D. Perry
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Sarah J. Morgan
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - George J. Kahaly
- Molecular Thyroid Research Laboratory, Department of Medicine I, Johannes Gutenberg University Medical Center, Langenbeckstreet 1, 55131 Mainz, Germany
| | - Marvin C. Gershengorn
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
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Puskarjov M, Fiumelli H, Briner A, Bodogan T, Demeter K, Lacoh CM, Mavrovic M, Blaesse P, Kaila K, Vutskits L. K-Cl Cotransporter 2-mediated Cl- Extrusion Determines Developmental Stage-dependent Impact of Propofol Anesthesia on Dendritic Spines. Anesthesiology 2017; 126:855-867. [PMID: 28301408 DOI: 10.1097/aln.0000000000001587] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND General anesthetics potentiating γ-aminobutyric acid (GABA)-mediated signaling are known to induce a persistent decrement in excitatory synapse number in the cerebral cortex when applied during early postnatal development, while an opposite action is produced at later stages. Here, the authors test the hypothesis that the effect of general anesthetics on synaptogenesis depends upon the efficacy of GABA receptor type A (GABAA)-mediated inhibition controlled by the developmental up-regulation of the potassium-chloride (K-Cl) cotransporter 2 (KCC2). METHODS In utero electroporation of KCC2 was used to prematurely increase the efficacy of (GABAA)-mediated inhibition in layer 2/3 pyramidal neurons in the immature rat somatosensory cortex. Parallel experiments with expression of the inward-rectifier potassium channel Kir2.1 were done to reduce intrinsic neuronal excitability. The effects of these genetic manipulations (n = 3 to 4 animals per experimental group) were evaluated using iontophoretic injection of Lucifer Yellow (n = 8 to 12 cells per animal). The total number of spines analyzed per group ranged between 907 and 3,371. RESULTS The authors found a robust effect of the developmental up-regulation of KCC2-mediated Cl transport on the age-dependent action of propofol on dendritic spines. Premature expression of KCC2, unlike expression of a transport-inactive KCC2 variant, prevented a propofol-induced decrease in spine density. In line with a reduction in neuronal excitability, the above result was qualitatively replicated by overexpression of Kir2.1. CONCLUSIONS The KCC2-dependent developmental increase in the efficacy of GABAA-mediated inhibition is a major determinant of the age-dependent actions of propofol on dendritic spinogenesis.
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Affiliation(s)
- Martin Puskarjov
- From the Department of Biosciences and Neuroscience Center (HiLIFE), University of Helsinki, Helsinki, Finland (M.P., M.M., P.B., K.K.); Division of Biological and Environmental Sciences and Technology, King Abdullah University of Science and Technology, Thuwal, Kingdom of Saudi Arabia (H.F.); Department of Anesthesiology, Pharmacology and Intensive Care, University Hospital of Geneva, Geneva, Switzerland (A.B., T.B., C.-M.L., L.V.); Department of Fundamental Neurosciences, University of Geneva Medical School, Geneva, Switzerland (A.B., T.B., K.D., L.V.); and Institute of Experimental Medicine of the Hungarian Academy of Sciences, Budapest, Hungary (K.D.). Current position: Institute of Physiology I, Westfälische Wilhelms-University Münster, Münster, Germany (P.B.)
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16
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Kourdougli N, Pellegrino C, Renko JM, Khirug S, Chazal G, Kukko-Lukjanov TK, Lauri SE, Gaiarsa JL, Zhou L, Peret A, Castrén E, Tuominen RK, Crépel V, Rivera C. Depolarizing γ-aminobutyric acid contributes to glutamatergic network rewiring in epilepsy. Ann Neurol 2017; 81:251-265. [PMID: 28074534 DOI: 10.1002/ana.24870] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 01/03/2017] [Accepted: 01/03/2017] [Indexed: 12/16/2023]
Abstract
OBJECTIVE Rewiring of excitatory glutamatergic neuronal circuits is a major abnormality in epilepsy. Besides the rewiring of excitatory circuits, an abnormal depolarizing γ-aminobutyric acidergic (GABAergic) drive has been hypothesized to participate in the epileptogenic processes. However, a remaining clinically relevant question is whether early post-status epilepticus (SE) evoked chloride dysregulation is important for the remodeling of aberrant glutamatergic neuronal circuits. METHODS Osmotic minipumps were used to infuse intracerebrally a specific inhibitor of depolarizing GABAergic transmission as well as a functionally blocking antibody toward the pan-neurotrophin receptor p75 (p75NTR ). The compounds were infused between 2 and 5 days after pilocarpine-induced SE. Immunohistochemistry for NKCC1, KCC2, and ectopic recurrent mossy fiber (rMF) sprouting as well as telemetric electroencephalographic and electrophysiological recordings were performed at day 5 and 2 months post-SE. RESULTS Blockade of NKCC1 after SE with the specific inhibitor bumetanide restored NKCC1 and KCC2 expression, normalized chloride homeostasis, and significantly reduced the glutamatergic rMF sprouting within the dentate gyrus. This mechanism partially involves p75NTR signaling, as bumetanide application reduced SE-induced p75NTR expression and functional blockade of p75NTR decreased rMF sprouting. The early transient (3 days) post-SE infusion of bumetanide reduced rMF sprouting and recurrent seizures in the chronic epileptic phase. INTERPRETATION Our findings show that early post-SE abnormal depolarizing GABA and p75NTR signaling fosters a long-lasting rearrangement of glutamatergic network that contributes to the epileptogenic process. This finding defines promising and novel targets to constrain reactive glutamatergic network rewiring in adult epilepsy. Ann Neurol 2017;81:251-265.
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Affiliation(s)
- Nazim Kourdougli
- Inserm Unit 901, Inmed, Marseille, France
- Mixed Unit of Research S901, Aix-Marseille University, Marseille, France
| | - Christophe Pellegrino
- Inserm Unit 901, Inmed, Marseille, France
- Mixed Unit of Research S901, Aix-Marseille University, Marseille, France
| | - Juho-Matti Renko
- Division of Pharmacology and Pharmacotherapy, University of Helsinki, Helsinki, Finland
| | | | - Geneviève Chazal
- Inserm Unit 901, Inmed, Marseille, France
- Mixed Unit of Research S901, Aix-Marseille University, Marseille, France
| | | | - Sari E Lauri
- Neuroscience Center, University of Helsinki, Helsinki, Finland
| | - Jean-Luc Gaiarsa
- Inserm Unit 901, Inmed, Marseille, France
- Mixed Unit of Research S901, Aix-Marseille University, Marseille, France
| | - Liang Zhou
- Neuroscience Center, University of Helsinki, Helsinki, Finland
| | - Angélique Peret
- Inserm Unit 901, Inmed, Marseille, France
- Mixed Unit of Research S901, Aix-Marseille University, Marseille, France
| | - Eero Castrén
- Neuroscience Center, University of Helsinki, Helsinki, Finland
| | - Raimo K Tuominen
- Division of Pharmacology and Pharmacotherapy, University of Helsinki, Helsinki, Finland
| | - Valérie Crépel
- Inserm Unit 901, Inmed, Marseille, France
- Mixed Unit of Research S901, Aix-Marseille University, Marseille, France
| | - Claudio Rivera
- Inserm Unit 901, Inmed, Marseille, France
- Mixed Unit of Research S901, Aix-Marseille University, Marseille, France
- Neuroscience Center, University of Helsinki, Helsinki, Finland
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17
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Abstract
OBJECTIVE The differentiation program for human thyroid follicular cells (TFCs) relies on the interplay between sequence-specific transcription factors and transcriptional co-regulators. Transcriptional co-activator with PDZ-binding motif (TAZ) is a co-activator that regulates several transcription factors, including PAX8 and NKX2-1, which play a central role in thyroid-specific gene transcription. TAZ and PAX8/NKX2-1 are co-expressed in the nuclei of thyroid cells, and TAZ interacts directly with both PAX8 and NKX2-1, leading to their enhanced transcriptional activity on the thyroglobulin (TG) promoter and additional genes. METHODS The use of a small molecule, ethacridine, recently identified as a TAZ activator, in the differentiation of thyroid cells from human embryonic stem (hES) cells was studied. First, endodermal cells were derived from hES cells using Activin A, followed by induction of differentiation into thyroid cells directed by ethacridine and thyrotropin (TSH). RESULTS The expression of TAZ was increased in the Activin A-derived endodermal cells by ethacridine in a dose-dependent manner and followed by increases in PAX8 and NKX2-1 when assessed by both quantitative polymerase chain reaction and immunostaining. Following further differentiation with the combination of ethacridine and TSH, the thyroid-specific genes TG, TPO, TSHR, and NIS were all induced in the differentiated hES cells. When these cells were cultured with extracellular matrix-coated dishes, thyroid follicle formation and abundant TG protein expression were observed. Furthermore, such hES cell-derived thyroid follicles showed a marked TSH-induced and dose-dependent increase in radioiodine uptake and protein-bound iodine accumulation. CONCLUSION These data show that fully functional human thyroid cells can be derived from hES cells using ethacridine, a TAZ activator, which induces thyroid-specific gene expression and promotes thyroid cell differentiation from the hES cells. These studies again demonstrate the importance of transcriptional regulation in thyroid cell development. This approach also yields functional human thyrocytes, without any gene transfection or complex culture conditions, by directly manipulating the transcriptional machinery without interfering with intermediate signaling events.
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Affiliation(s)
- Risheng Ma
- Thyroid Research Unit, Department of Medicine, The Icahn School of Medicine at Mount Sinai, Mount Sinai Beth Israel Medical Center and the James J. Peters VA Medical Center , New York, New York
| | - Syed A Morshed
- Thyroid Research Unit, Department of Medicine, The Icahn School of Medicine at Mount Sinai, Mount Sinai Beth Israel Medical Center and the James J. Peters VA Medical Center , New York, New York
| | - Rauf Latif
- Thyroid Research Unit, Department of Medicine, The Icahn School of Medicine at Mount Sinai, Mount Sinai Beth Israel Medical Center and the James J. Peters VA Medical Center , New York, New York
| | - Terry F Davies
- Thyroid Research Unit, Department of Medicine, The Icahn School of Medicine at Mount Sinai, Mount Sinai Beth Israel Medical Center and the James J. Peters VA Medical Center , New York, New York
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Ostroumov A, Thomas AM, Kimmey BA, Karsch JS, Doyon WM, Dani JA. Stress Increases Ethanol Self-Administration via a Shift toward Excitatory GABA Signaling in the Ventral Tegmental Area. Neuron 2016; 92:493-504. [PMID: 27720487 PMCID: PMC5091663 DOI: 10.1016/j.neuron.2016.09.029] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Revised: 07/13/2016] [Accepted: 09/02/2016] [Indexed: 12/23/2022]
Abstract
Stress is a well-known risk factor for subsequent alcohol abuse, but the neural mechanisms underlying interactions between stress and alcohol remain largely unknown. Addictive drug reinforcement and stress signaling involve common neural circuitry, including the mesolimbic dopamine system. We demonstrate in rodents that pre-exposure to stress attenuates alcohol-induced dopamine responses and increases alcohol self-administration. The blunted dopamine signaling resulted from ethanol-induced excitation of GABA neurons in the ventral tegmental area. Excitation of GABA neurons was mediated by GABAA receptor activation and involved stress-induced functional downregulation of the K+, Cl- cotransporter, KCC2. Blocking stress hormone receptors, enhancing KCC2 function, or preventing excitatory GABA signaling by alternative methods all prevented the attenuated alcohol-induced dopamine response and prevented the increased alcohol self-administration. These results demonstrate that stress alters the neural and behavioral responses to alcohol through a neuroendocrine signal that shifts inhibitory GABA transmission toward excitation.
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Affiliation(s)
- Alexey Ostroumov
- Department of Neuroscience, Mahoney Institute for Neurosciences, Perelman School for Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Alyse M Thomas
- Department of Neuroscience, Mahoney Institute for Neurosciences, Perelman School for Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Blake A Kimmey
- Department of Neuroscience, Mahoney Institute for Neurosciences, Perelman School for Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Jordan S Karsch
- Department of Neuroscience, Mahoney Institute for Neurosciences, Perelman School for Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - William M Doyon
- Department of Neuroscience, Mahoney Institute for Neurosciences, Perelman School for Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - John A Dani
- Department of Neuroscience, Mahoney Institute for Neurosciences, Perelman School for Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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Roussa E, Speer JM, Chudotvorova I, Khakipoor S, Smirnov S, Rivera C, Krieglstein K. The membrane trafficking and functionality of the K+-Cl- co-transporter KCC2 is regulated by TGF-β2. J Cell Sci 2016; 129:3485-98. [PMID: 27505893 PMCID: PMC5047681 DOI: 10.1242/jcs.189860] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 08/02/2016] [Indexed: 02/02/2023] Open
Abstract
Functional activation of the neuronal K(+)-Cl(-) co-transporter KCC2 (also known as SLC12A5) is a prerequisite for shifting GABAA responses from depolarizing to hyperpolarizing during development. Here, we introduce transforming growth factor β2 (TGF-β2) as a new regulator of KCC2 membrane trafficking and functional activation. TGF-β2 controls membrane trafficking, surface expression and activity of KCC2 in developing and mature mouse primary hippocampal neurons, as determined by immunoblotting, immunofluorescence, biotinylation of surface proteins and KCC2-mediated Cl(-) extrusion. We also identify the signaling pathway from TGF-β2 to cAMP-response-element-binding protein (CREB) and Ras-associated binding protein 11b (Rab11b) as the underlying mechanism for TGF-β2-mediated KCC2 trafficking and functional activation. TGF-β2 increases colocalization and interaction of KCC2 with Rab11b, as determined by 3D stimulated emission depletion (STED) microscopy and co-immunoprecipitation, respectively, induces CREB phosphorylation, and enhances Rab11b gene expression. Loss of function of either CREB1 or Rab11b suppressed TGF-β2-dependent KCC2 trafficking, surface expression and functionality. Thus, TGF-β2 is a new regulatory factor for KCC2 functional activation and membrane trafficking, and a putative indispensable molecular determinant for the developmental shift of GABAergic transmission.
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Affiliation(s)
- Eleni Roussa
- Institute of Anatomy and Cell Biology, Department of Molecular Embryology, Faculty of Medicine, University of Freiburg, Albertstrasse 17, Freiburg D-79104, Germany Institute of Anatomy and Cell Biology, Department of Neuroanatomy, Faculty of Medicine, University of Freiburg, Albertstrasse 17, Freiburg D-79104, Germany
| | - Jan Manuel Speer
- Institute of Anatomy and Cell Biology, Department of Molecular Embryology, Faculty of Medicine, University of Freiburg, Albertstrasse 17, Freiburg D-79104, Germany
| | - Ilona Chudotvorova
- Institute of Anatomy and Cell Biology, Department of Molecular Embryology, Faculty of Medicine, University of Freiburg, Albertstrasse 17, Freiburg D-79104, Germany
| | - Shokoufeh Khakipoor
- Institute of Anatomy and Cell Biology, Department of Molecular Embryology, Faculty of Medicine, University of Freiburg, Albertstrasse 17, Freiburg D-79104, Germany
| | - Sergei Smirnov
- Institute of Biotechnology, University of Helsinki, Viikinkaari 9, Helsinki FIN-00014, Finland
| | - Claudio Rivera
- Institute of Biotechnology, University of Helsinki, Viikinkaari 9, Helsinki FIN-00014, Finland
| | - Kerstin Krieglstein
- Institute of Anatomy and Cell Biology, Department of Molecular Embryology, Faculty of Medicine, University of Freiburg, Albertstrasse 17, Freiburg D-79104, Germany
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20
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Sakai H, Fujii T. Functional complexes of the proton pump and chloride transporter in gastric acid secretion. Nihon Rinsho 2016; 74:1401-1405. [PMID: 30562450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Proton(H+) of gastric acid(HCl) is actively secreted by gastric proton pump (H+, K+- ATPase) in the parietal cells. The proton pump is expressed in both tubulovesicles and apical membrane of the cells. In resting parietal cells, tubulovesicles are present in intracellular compartments underlying the apical membrane and forming a reticulated meshwork. Upon stimulation, tubulovesicles fuse each other and connect with the apical membrane, resulting in massive acid secretion. On the other hand, the mechanism of apical Cl- transport for HCl secretion is not fully understood, although several Cl- transporters and Cl- channels have been reported to be the candidate. Here, we summarized the function of Cl- transporters such as KCC4, a K+-Cl- cotransporter, and ClC-5, a Cl-/H+ exchanger, in gastric acid secretion.
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21
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Nicola JP, Peyret V, Nazar M, Romero JM, Lucero AM, Montesinos MDM, Bocco JL, Pellizas CG, Masini-Repiso AM. S-Nitrosylation of NF-κB p65 Inhibits TSH-Induced Na(+)/I(-) Symporter Expression. Endocrinology 2015; 156:4741-54. [PMID: 26587909 DOI: 10.1210/en.2015-1192] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Nitric oxide (NO) is a ubiquitous signaling molecule involved in a wide variety of cellular physiological processes. In thyroid cells, NO-synthase III-endogenously produced NO reduces TSH-stimulated thyroid-specific gene expression, suggesting a potential autocrine role of NO in modulating thyroid function. Further studies indicate that NO induces thyroid dedifferentiation, because NO donors repress TSH-stimulated iodide (I(-)) uptake. Here, we investigated the molecular mechanism underlying the NO-inhibited Na(+)/I(-) symporter (NIS)-mediated I(-) uptake in thyroid cells. We showed that NO donors reduce I(-) uptake in a concentration-dependent manner, which correlates with decreased NIS protein expression. NO-reduced I(-) uptake results from transcriptional repression of NIS gene rather than posttranslational modifications reducing functional NIS expression at the plasma membrane. We observed that NO donors repress TSH-induced NIS gene expression by reducing the transcriptional activity of the nuclear factor-κB subunit p65. NO-promoted p65 S-nitrosylation reduces p65-mediated transactivation of the NIS promoter in response to TSH stimulation. Overall, our data are consistent with the notion that NO plays a role as an inhibitory signal to counterbalance TSH-stimulated nuclear factor-κB activation, thus modulating thyroid hormone biosynthesis.
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Affiliation(s)
- Juan Pablo Nicola
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (J.P.N., V.P., M.N., A.M.L., M.d.M.M., J.L.B., C.G.P., A.M.M.-R.) and Centro de Investigaciones en Química Biológica (J.M.R.), Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba 5000, Argentina
| | - Victoria Peyret
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (J.P.N., V.P., M.N., A.M.L., M.d.M.M., J.L.B., C.G.P., A.M.M.-R.) and Centro de Investigaciones en Química Biológica (J.M.R.), Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba 5000, Argentina
| | - Magalí Nazar
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (J.P.N., V.P., M.N., A.M.L., M.d.M.M., J.L.B., C.G.P., A.M.M.-R.) and Centro de Investigaciones en Química Biológica (J.M.R.), Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba 5000, Argentina
| | - Jorge Miguel Romero
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (J.P.N., V.P., M.N., A.M.L., M.d.M.M., J.L.B., C.G.P., A.M.M.-R.) and Centro de Investigaciones en Química Biológica (J.M.R.), Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba 5000, Argentina
| | - Ariel Maximiliano Lucero
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (J.P.N., V.P., M.N., A.M.L., M.d.M.M., J.L.B., C.G.P., A.M.M.-R.) and Centro de Investigaciones en Química Biológica (J.M.R.), Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba 5000, Argentina
| | - María del Mar Montesinos
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (J.P.N., V.P., M.N., A.M.L., M.d.M.M., J.L.B., C.G.P., A.M.M.-R.) and Centro de Investigaciones en Química Biológica (J.M.R.), Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba 5000, Argentina
| | - José Luis Bocco
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (J.P.N., V.P., M.N., A.M.L., M.d.M.M., J.L.B., C.G.P., A.M.M.-R.) and Centro de Investigaciones en Química Biológica (J.M.R.), Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba 5000, Argentina
| | - Claudia Gabriela Pellizas
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (J.P.N., V.P., M.N., A.M.L., M.d.M.M., J.L.B., C.G.P., A.M.M.-R.) and Centro de Investigaciones en Química Biológica (J.M.R.), Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba 5000, Argentina
| | - Ana María Masini-Repiso
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (J.P.N., V.P., M.N., A.M.L., M.d.M.M., J.L.B., C.G.P., A.M.M.-R.) and Centro de Investigaciones en Química Biológica (J.M.R.), Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba 5000, Argentina
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22
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Sárvári M, Kalló I, Hrabovszky E, Solymosi N, Rodolosse A, Vastagh C, Auer H, Liposits Z. Hippocampal Gene Expression Is Highly Responsive to Estradiol Replacement in Middle-Aged Female Rats. Endocrinology 2015; 156:2632-45. [PMID: 25924104 DOI: 10.1210/en.2015-1109] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In the hippocampus, estrogens are powerful modulators of neurotransmission, synaptic plasticity and neurogenesis. In women, menopause is associated with increased risk of memory disturbances, which can be attenuated by timely estrogen therapy. In animal models of menopause, 17β-estradiol (E2) replacement improves hippocampus-dependent spatial memory. Here, we explored the effect of E2 replacement on hippocampal gene expression in a rat menopause model. Middle-aged ovariectomized female rats were treated continuously for 29 days with E2, and then, the hippocampal transcriptome was investigated with Affymetrix expression arrays. Microarray data were analyzed by Bioconductor packages and web-based softwares, and verified with quantitative PCR. At standard fold change selection criterion, 156 genes responded to E2. All alterations but 4 were transcriptional activation. Robust activation (fold change > 10) occurred in the case of transthyretin, klotho, claudin 2, prolactin receptor, ectodin, coagulation factor V, Igf2, Igfbp2, and sodium/sulfate symporter. Classification of the 156 genes revealed major groups, including signaling (35 genes), metabolism (31 genes), extracellular matrix (17 genes), and transcription (16 genes). We selected 33 genes for further studies, and all changes were confirmed by real-time PCR. The results suggest that E2 promotes retinoid, growth factor, homeoprotein, neurohormone, and neurotransmitter signaling, changes metabolism, extracellular matrix composition, and transcription, and induces protective mechanisms via genomic effects. We propose that these mechanisms contribute to effects of E2 on neurogenesis, neural plasticity, and memory functions. Our findings provide further support for the rationale to develop safe estrogen receptor ligands for the maintenance of cognitive performance in postmenopausal women.
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Affiliation(s)
- Miklós Sárvári
- Laboratory of Endocrine Neurobiology (M.S., I.K., E.H., C.V., Z.L.), Institute of Experimental Medicine, Hungarian Academy of Sciences, 1083 Budapest, Hungary; Faculty of Information Technology and Bionics (I.K., Z.L.), Pázmány Péter Catholic University, 1083 Budapest, Hungary; Faculty of Veterinary Science (N.S.), Szent István University, 1078 Budapest, Hungary; Functional Genomics Core (A.R.), Institute for Research in Biomedicine, 08028 Barcelona, Spain; and Functional Genomics Consulting (H.A.), 08780 Palleja, Spain
| | - Imre Kalló
- Laboratory of Endocrine Neurobiology (M.S., I.K., E.H., C.V., Z.L.), Institute of Experimental Medicine, Hungarian Academy of Sciences, 1083 Budapest, Hungary; Faculty of Information Technology and Bionics (I.K., Z.L.), Pázmány Péter Catholic University, 1083 Budapest, Hungary; Faculty of Veterinary Science (N.S.), Szent István University, 1078 Budapest, Hungary; Functional Genomics Core (A.R.), Institute for Research in Biomedicine, 08028 Barcelona, Spain; and Functional Genomics Consulting (H.A.), 08780 Palleja, Spain
| | - Erik Hrabovszky
- Laboratory of Endocrine Neurobiology (M.S., I.K., E.H., C.V., Z.L.), Institute of Experimental Medicine, Hungarian Academy of Sciences, 1083 Budapest, Hungary; Faculty of Information Technology and Bionics (I.K., Z.L.), Pázmány Péter Catholic University, 1083 Budapest, Hungary; Faculty of Veterinary Science (N.S.), Szent István University, 1078 Budapest, Hungary; Functional Genomics Core (A.R.), Institute for Research in Biomedicine, 08028 Barcelona, Spain; and Functional Genomics Consulting (H.A.), 08780 Palleja, Spain
| | - Norbert Solymosi
- Laboratory of Endocrine Neurobiology (M.S., I.K., E.H., C.V., Z.L.), Institute of Experimental Medicine, Hungarian Academy of Sciences, 1083 Budapest, Hungary; Faculty of Information Technology and Bionics (I.K., Z.L.), Pázmány Péter Catholic University, 1083 Budapest, Hungary; Faculty of Veterinary Science (N.S.), Szent István University, 1078 Budapest, Hungary; Functional Genomics Core (A.R.), Institute for Research in Biomedicine, 08028 Barcelona, Spain; and Functional Genomics Consulting (H.A.), 08780 Palleja, Spain
| | - Annie Rodolosse
- Laboratory of Endocrine Neurobiology (M.S., I.K., E.H., C.V., Z.L.), Institute of Experimental Medicine, Hungarian Academy of Sciences, 1083 Budapest, Hungary; Faculty of Information Technology and Bionics (I.K., Z.L.), Pázmány Péter Catholic University, 1083 Budapest, Hungary; Faculty of Veterinary Science (N.S.), Szent István University, 1078 Budapest, Hungary; Functional Genomics Core (A.R.), Institute for Research in Biomedicine, 08028 Barcelona, Spain; and Functional Genomics Consulting (H.A.), 08780 Palleja, Spain
| | - Csaba Vastagh
- Laboratory of Endocrine Neurobiology (M.S., I.K., E.H., C.V., Z.L.), Institute of Experimental Medicine, Hungarian Academy of Sciences, 1083 Budapest, Hungary; Faculty of Information Technology and Bionics (I.K., Z.L.), Pázmány Péter Catholic University, 1083 Budapest, Hungary; Faculty of Veterinary Science (N.S.), Szent István University, 1078 Budapest, Hungary; Functional Genomics Core (A.R.), Institute for Research in Biomedicine, 08028 Barcelona, Spain; and Functional Genomics Consulting (H.A.), 08780 Palleja, Spain
| | - Herbert Auer
- Laboratory of Endocrine Neurobiology (M.S., I.K., E.H., C.V., Z.L.), Institute of Experimental Medicine, Hungarian Academy of Sciences, 1083 Budapest, Hungary; Faculty of Information Technology and Bionics (I.K., Z.L.), Pázmány Péter Catholic University, 1083 Budapest, Hungary; Faculty of Veterinary Science (N.S.), Szent István University, 1078 Budapest, Hungary; Functional Genomics Core (A.R.), Institute for Research in Biomedicine, 08028 Barcelona, Spain; and Functional Genomics Consulting (H.A.), 08780 Palleja, Spain
| | - Zsolt Liposits
- Laboratory of Endocrine Neurobiology (M.S., I.K., E.H., C.V., Z.L.), Institute of Experimental Medicine, Hungarian Academy of Sciences, 1083 Budapest, Hungary; Faculty of Information Technology and Bionics (I.K., Z.L.), Pázmány Péter Catholic University, 1083 Budapest, Hungary; Faculty of Veterinary Science (N.S.), Szent István University, 1078 Budapest, Hungary; Functional Genomics Core (A.R.), Institute for Research in Biomedicine, 08028 Barcelona, Spain; and Functional Genomics Consulting (H.A.), 08780 Palleja, Spain
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Spitzweg C, Bible KC, Hofbauer LC, Morris JC. Advanced radioiodine-refractory differentiated thyroid cancer: the sodium iodide symporter and other emerging therapeutic targets. Lancet Diabetes Endocrinol 2014; 2:830-42. [PMID: 24898835 DOI: 10.1016/s2213-8587(14)70051-8] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Approximately 30% of patients with advanced, metastatic differentiated thyroid cancer have radioiodine-refractory disease, based on decreased expression of the sodium iodide symporter SLC5A5 (NIS), diminished membrane targeting of NIS, or both. Patients with radioiodine-refractory disease, therefore, are not amenable to (131)I therapy, which is the initial systemic treatment of choice for non-refractory metastatic thyroid cancer. Patients with radioiodine-refractory cancer have historically had poor outcomes, partly because these cancers often respond poorly to cytotoxic chemotherapy. In the past decade, however, considerable progress has been made in delineating the molecular pathogenesis of radioiodine-refractory thyroid cancer. As a result of the identification of key genetic and epigenetic alterations and dysregulated signalling pathways, multiple biologically targeted drugs, in particular tyrosine-kinase inhibitors, have been evaluated in clinical trials with promising results and have begun to meaningfully impact clinical practice. In this Review, we summarise the current knowledge of the molecular pathogenesis of advanced differentiated thyroid cancer and discuss findings from clinical trials of targeted drugs in patients with radioiodine-refractory disease. Additionally, we focus on the molecular basis of loss of NIS expression, function, or both in refractory disease, and discuss preclinical and clinical data on restoration of radioiodine uptake.
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Affiliation(s)
- Christine Spitzweg
- Department of Internal Medicine II - Campus Grosshadern, University Hospital of Munich, Munich, Germany.
| | - Keith C Bible
- Division of Medical Oncology, Mayo Clinic, Rochester, MN, USA
| | - Lorenz C Hofbauer
- Division of Endocrinology and Metabolic Bone Disease, Department of Medicine III, Technische Universität, Dresden, Germany
| | - John C Morris
- Division of Endocrinology and Metabolism, Mayo Clinic, Rochester, MN, USA
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Abstract
Seizures are a common manifestation of acute neurologic insults in neonates and are often resistant to the standard antiepileptic drugs that are efficacious in children and adults. The paucity of evidence-based treatment guidelines, coupled with a rudimentary understanding of disease pathogenesis, has made the current treatment of neonatal seizures empiric and often ineffective, highlighting the need for novel therapies. Key developmental differences in γ-aminobutyric acid (GABA)ergic neurotransmission between the immature and mature brain, and trauma-induced alterations in the function of the cation-chloride cotransporters (CCCs) NKCC1 and KCC2, probably contribute to the poor efficacy of standard antiepileptic drugs used in the treatment of neonatal seizures. Although CCCs are attractive drug targets, bumetanide and other existing CCC inhibitors are suboptimal because of pharmacokinetic constraints and lack of target specificity. Newer approaches including isoform-specific NKCC1 inhibitors with increased central nervous system penetration, and direct and indirect strategies to enhance KCC2-mediated neuronal chloride extrusion, might allow therapeutic modulation of the GABAergic system for neonatal seizure treatment. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here.
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Affiliation(s)
- Martin Puskarjov
- Department of Biosciences and Neuroscience Center, University of HelsinkiHelsinki, Finland
| | - Kristopher T Kahle
- Department of Neurosurgery, Harvard Medical School, Massachusetts General HospitalBoston, Massachusetts, U.S.A
| | - Eva Ruusuvuori
- Department of Biosciences and Neuroscience Center, University of HelsinkiHelsinki, Finland
| | - Kai Kaila
- Department of Biosciences and Neuroscience Center, University of HelsinkiHelsinki, Finland
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25
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Watanabe H, Yashiro T, Tohjo Y, Konishi Y. Non-Involvement of the Human Monocarboxylic Acid Transporter 1 (MCT1) in the Transport of Phenolic Acid. Biosci Biotechnol Biochem 2014; 70:1928-33. [PMID: 16926505 DOI: 10.1271/bbb.60093] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Phenolic acids such as p-coumaric acid and microbial metabolites of poorly absorbed polyphenols are absorbed by the monocarboxylic acid transporter (MCT)-mediated transport system which is identical to the fluorescein/H(+) cotransport system. We focus here on the physiological impact of MCT-mediated absorption and distribution. We examined whether MCT1, the best-characterized isoform found in almost all tissues, is involved in this MCT-mediated transport system. The induction of MCT1 expression in Caco-2 cells by a treatment with sodium butyrate (NaBut) did not increase the fluorescein permeability. Moreover, the transfection of Caco-2 cells with an expression vector encoding MCT1 caused no increase in either the permeability or uptake of fluorescein. Furthermore, in the MCT1-expressing oocytes, no increase of p-coumaric acid uptake was apparent, whereas the uptake of salicylic acid, a substrate of MCT1, nearly doubled. Our data therefore establish that MCT1 was not involved in the MCT-mediated transport of phenolic acids.
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Affiliation(s)
- Hirohito Watanabe
- Department of Life Sciences, Faculty of Agriculture, Meiji University, Kanagawa, Japan
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26
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Abdulrahman RM, Boon MR, Sips HCM, Guigas B, Rensen PCN, Smit JWA, Hovens GCJ. Impact of Metformin and compound C on NIS expression and iodine uptake in vitro and in vivo: a role for CRE in AMPK modulation of thyroid function. Thyroid 2014; 24:78-87. [PMID: 23819433 DOI: 10.1089/thy.2013.0041] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
BACKGROUND Although adenosine monophosphate activated protein kinase (AMPK) plays a crucial role in energy metabolism, a direct effect of AMPK modulation on thyroid function has only recently been reported, and much of its function in the thyroid is currently unknown. The aim of this study was to investigate the mechanism of AMPK modulation in iodide uptake. Furthermore, we wanted to investigate the potential of the AMPK inhibitor compound C as an enhancer of iodide uptake by thyrocytes. METHODS The in vitro and in vivo effects of AMPK modulation on sodium-iodide symporter (NIS) protein levels and iodide uptake were examined in follicular rat thyroid cell-line cells and C57Bl6/J mice. Activation of AMPK by metformin resulted in a strong reduction of iodide uptake (up to sixfold with 5 mM metformin after 96 h) and NIS protein levels in vitro, whereas AMPK inhibition by compound C not only stimulated iodide uptake but also enhanced NIS protein levels both in vitro (up to sevenfold with 1 μM compound C after 96 h) and in vivo (1.5-fold after daily injections with 20 mg/kg for 4 days). We investigated the regulation of NIS expression by AMPK using a range of promoter constructs consisting of either the NIS promoter or isolated CRE (cAMP response element) and NF-κB elements, which are present within the NIS promoter. RESULTS Metformin reduced NIS promoter activity (0.6-fold of control), whereas compound C stimulated its activity (3.4-fold) after 4 days. This largely coincides with CRE activation (0.6- and 3.0-fold). These experiments show that AMPK exerts its effects on iodide uptake, at least partly, through the CRE element in the NIS promoter. Furthermore, we have used AMPK-alpha1 knockout mice to determine the long-term effects of AMPK inhibition without chemical compounds. These mice have a less active thyroid, as shown by reduced colloid volume and reduced responsiveness to thyrotropin. CONCLUSION NIS expression and iodine uptake in thyrocytes can be modulated by metformin and compound C. These compounds exert their effect by modulation of AMPK, which, in turn, regulates the activation of the CRE element in the NIS promoter. Overall, this suggests that the use of AMPK modulating compounds may be useful for the enhancement of iodide uptake by thyrocytes, which could be useful for the treatment of thyroid cancer patients with radioactive iodine.
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Affiliation(s)
- Randa M Abdulrahman
- 1 Department of Endocrinology and Metabolic Diseases, University Medical Center , Leiden, The Netherlands
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Deeb TZ, Nakamura Y, Frost GD, Davies PA, Moss SJ. Disrupted Cl(-) homeostasis contributes to reductions in the inhibitory efficacy of diazepam during hyperexcited states. Eur J Neurosci 2013; 38:2453-67. [PMID: 23627375 PMCID: PMC3735799 DOI: 10.1111/ejn.12241] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Revised: 03/29/2013] [Accepted: 03/31/2013] [Indexed: 11/28/2022]
Abstract
The K(+) -Cl(-) cotransporter type 2 is the major Cl(-) extrusion mechanism in most adult neurons. This process in turn leads to Cl(-) influx upon activation of γ-aminobutyric acid type A (GABAA ) receptors and the canonical hyperpolarising inhibitory postsynaptic potential. Several neurological disorders are treated with drugs that target and enhance GABAA receptor signaling, including the commonly used benzodiazepine diazepam and the anesthetic propofol. Some of these disorders are also associated with deficits in GABAA signaling and become less sensitive to therapeutic drugs that target GABAA receptors. To date, it is unknown if alterations in the neuronal Cl(-) gradient affect the efficacies of diazepam and propofol. We therefore used the in vitro model of glutamate-induced hyperexcitability to test if alterations in the Cl(-) gradient affect the efficacy of GABAA modulators. We exclusively utilised the gramicidin perforated-patch-clamp configuration to preserve the endogenous Cl(-) gradient in rat neurons. Brief exposure to glutamate reduced the inhibitory efficacy of diazepam within 5 min, which was caused by the collapse of the Cl(-) gradient, and not due to reductions in GABAA receptor number. Unlike diazepam, propofol retained its efficacy by shunting the membrane conductance despite the glutamate-induced appearance of depolarising GABAA -mediated currents. Similarly, pharmacological inhibition of K(+) -Cl(-) cotransporter type 2 by furosemide disrupted Cl(-) homeostasis and reduced the efficacy of diazepam but not propofol. Collectively our results suggest that pathological hyperexcitable conditions could cause the rapid accumulation of intracellular Cl(-) and the appearance of depolarising GABAA -mediated currents that would decrease the efficacy of diazepam.
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Affiliation(s)
- Tarek Z Deeb
- Department of Neuroscience, Tufts University, Boston, MA, USA
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Löscher W, Puskarjov M, Kaila K. Cation-chloride cotransporters NKCC1 and KCC2 as potential targets for novel antiepileptic and antiepileptogenic treatments. Neuropharmacology 2013; 69:62-74. [PMID: 22705273 DOI: 10.1016/j.neuropharm.2012.05.045] [Citation(s) in RCA: 198] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Revised: 05/22/2012] [Accepted: 05/28/2012] [Indexed: 12/31/2022]
Abstract
In cortical and hippocampal neurons, cation-chloride cotransporters (CCCs) control the reversal potential (EGABA) of GABAA receptor-mediated current and voltage responses and, consequently, they modulate the efficacy of GABAergic inhibition. Two members of the CCC family, KCC2 (the major neuron-specific K-Cl cotransporter; KCC isoform 2) and NKCC1 (the Na-K-2Cl cotransporter isoform 1 which is expressed in both neurons and glial cells) have attracted much interest in studies on GABAergic signaling under both normal and pathophysiological conditions, such as epilepsy. There is tentative evidence that loop diuretic compounds such as furosemide and bumetanide may have clinically relevant antiepileptic actions, especially when administered in combination with conventional GABA-mimetic drugs such as phenobarbital. Furosemide is a non-selective inhibitor of CCCs while at low concentrations bumetanide is selective for NKCCs. Search for novel antiepileptic drugs (AEDs) is highly motivated especially for the treatment of neonatal seizures which are often resistant to, or even aggravated by conventional AEDs. This review shows that the antiepileptic effects of loop diuretics described in the pertinent literature are based on widely heterogeneous mechanisms ranging from actions on both neuronal NKCC1 and KCC2 to modulation of the brain extracellular volume fraction. A promising strategy for the development of novel CCC-blocking AEDs is based on prodrugs that are activated following their passage across the blood-brain barrier. This article is part of the Special Issue entitled 'New Targets and Approaches to the Treatment of Epilepsy'.
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Affiliation(s)
- Wolfgang Löscher
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Hannover, Germany.
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29
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Ho AL, Grewal RK, Leboeuf R, Sherman EJ, Pfister DG, Deandreis D, Pentlow KS, Zanzonico PB, Haque S, Gavane S, Ghossein RA, Ricarte-Filho JC, Domínguez JM, Shen R, Tuttle RM, Larson SM, Fagin JA. Selumetinib-enhanced radioiodine uptake in advanced thyroid cancer. N Engl J Med 2013; 368:623-32. [PMID: 23406027 PMCID: PMC3615415 DOI: 10.1056/nejmoa1209288] [Citation(s) in RCA: 526] [Impact Index Per Article: 47.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Metastatic thyroid cancers that are refractory to radioiodine (iodine-131) are associated with a poor prognosis. In mouse models of thyroid cancer, selective mitogen-activated protein kinase (MAPK) pathway antagonists increase the expression of the sodium-iodide symporter and uptake of iodine. Their effects in humans are not known. METHODS We conducted a study to determine whether the MAPK kinase (MEK) 1 and MEK2 inhibitor selumetinib (AZD6244, ARRY-142886) could reverse refractoriness to radioiodine in patients with metastatic thyroid cancer. After stimulation with thyrotropin alfa, dosimetry with iodine-124 positron-emission tomography (PET) was performed before and 4 weeks after treatment with selumetinib (75 mg twice daily). If the second iodine-124 PET study indicated that a dose of iodine-131 of 2000 cGy or more could be delivered to the metastatic lesion or lesions, therapeutic radioiodine was administered while the patient was receiving selumetinib. RESULTS Of 24 patients screened for the study, 20 could be evaluated. The median age was 61 years (range, 44 to 77), and 11 patients were men. Nine patients had tumors with BRAF mutations, and 5 patients had tumors with mutations of NRAS. Selumetinib increased the uptake of iodine-124 in 12 of the 20 patients (4 of 9 patients with BRAF mutations and 5 of 5 patients with NRAS mutations). Eight of these 12 patients reached the dosimetry threshold for radioiodine therapy, including all 5 patients with NRAS mutations. Of the 8 patients treated with radioiodine, 5 had confirmed partial responses and 3 had stable disease; all patients had decreases in serum thyroglobulin levels (mean reduction, 89%). No toxic effects of grade 3 or higher attributable by the investigators to selumetinib were observed. One patient received a diagnosis of myelodysplastic syndrome more than 51 weeks after radioiodine treatment, with progression to acute leukemia. CONCLUSIONS Selumetinib produces clinically meaningful increases in iodine uptake and retention in a subgroup of patients with thyroid cancer that is refractory to radioiodine; the effectiveness may be greater in patients with RAS-mutant disease. (Funded by the American Thyroid Association and others; ClinicalTrials.gov number, NCT00970359.).
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Affiliation(s)
- Alan L Ho
- Head and Neck Oncology Service, Department of Medicine, Memorial Sloan-Kettering Cancer Center and Weill Cornell Medical College, New York, NY 10065, USA
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30
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Piermarini PM, Hine RM, Schepel M, Miyauchi J, Beyenbach KW. Role of an apical K,Cl cotransporter in urine formation by renal tubules of the yellow fever mosquito (Aedes aegypti). Am J Physiol Regul Integr Comp Physiol 2011; 301:R1318-37. [PMID: 21813871 PMCID: PMC3213945 DOI: 10.1152/ajpregu.00223.2011] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2011] [Accepted: 07/29/2011] [Indexed: 01/07/2023]
Abstract
The K,Cl cotransporters (KCCs) of the SLC12 superfamily play critical roles in the regulation of cell volume, concentrations of intracellular Cl(-), and epithelial transport in vertebrate tissues. To date, the role(s) of KCCs in the renal functions of mosquitoes and other insects is less clear. In the present study, we sought molecular and functional evidence for the presence of a KCC in renal (Malpighian) tubules of the mosquito Aedes aegypti. Using RT-PCR on Aedes Malpighian tubules, we identified five alternatively spliced partial cDNAs that encode putative SLC12-like KCCs. The majority transcript is AeKCC1-A(1); its full-length cDNA was cloned. After expression of the AeKCC1-A protein in Xenopus oocytes, the Cl(-)-dependent uptake of (86)Rb(+) is 1) activated by 1 mM N-ethylmaleimide and cell swelling, 2) blocked by 100 μM dihydroindenyloxyalkanoic acid (DIOA), and 3) dependent upon N-glycosylation of AeKCC1-A. In Aedes Malpighian tubules, AeKCC1 immunoreactivity localizes to the apical brush border of principal cells, which are the predominant cell type in the epithelium. In vitro physiological assays of Malpighian tubules show that peritubular DIOA (10 μM): 1) significantly reduces both the control and diuretic rates of transepithelial fluid secretion and 2) has negligible effects on the membrane voltage and input resistance of principal cells. Taken together, the above observations indicate the presence of a KCC in the apical membrane of principal cells where it participates in a major electroneutral transport pathway for the transepithelial secretion of fluid in this highly electrogenic epithelium.
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Affiliation(s)
- Peter M Piermarini
- Department of Biomedical Sciences, Cornell University, Ithaca, New York, USA.
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Viitanen T, Ruusuvuori E, Kaila K, Voipio J. The K+-Cl cotransporter KCC2 promotes GABAergic excitation in the mature rat hippocampus. J Physiol 2010; 588:1527-40. [PMID: 20211979 PMCID: PMC2876807 DOI: 10.1113/jphysiol.2009.181826] [Citation(s) in RCA: 152] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2009] [Accepted: 03/02/2010] [Indexed: 12/12/2022] Open
Abstract
GABAergic excitatory [K(+)](o) transients can be readily evoked in the mature rat hippocampus by intense activation of GABA(A) receptors (GABA(A)Rs). Here we show that these [K(+)](o) responses induced by high-frequency stimulation or GABA(A) agonist application are generated by the neuronal K(+)-Cl() cotransporter KCC2 and that the transporter-mediated KCl extrusion is critically dependent on the bicarbonate-driven accumulation of Cl() in pyramidal neurons. The mechanism underlying GABAergic [K(+)](o) transients was studied in CA1 stratum pyramidale using intracellular sharp microelectrodes and extracellular ion-sensitive microelectrodes. The evoked [K(+)](o) transients, as well as the associated afterdischarges, were strongly suppressed by 0.5-1 mm furosemide, a KCl cotransport inhibitor. Importantly, the GABA(A)R-mediated intrapyramidal accumulation of Cl(), as measured by monitoring the reversal potential of fused IPSPs, was unaffected by the drug. It was further confirmed that the reduction in the [K(+)](o) transients was not due to effects of furosemide on the Na(+)-dependent K(+)-Cl() cotransporter NKCC1 or on intraneuronal carbonic anhydrase activity. Blocking potassium channels by Ba(2+) enhanced [K(+)](o) transients whereas pyramidal cell depolarizations were attenuated in further agreement with a lack of contribution by channel-mediated K(+) efflux. The key role of the GABA(A)R channel-mediated anion fluxes in the generation of the [K(+)](o) transients was examined in experiments where bicarbonate was replaced with formate. This anion substitution had no significant effect on the rate of Cl() accumulation, [K(+)](o) response or afterdischarges. Our findings reveal a novel excitatory mode of action of KCC2 that can have substantial implications for the role of GABAergic transmission during ictal epileptiform activity.
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Affiliation(s)
- Tero Viitanen
- Department of Biosciences, PO Box 65, FI-00014 University of Helsinki, Helsinki, Finland
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Gusev GP, Agalakova NI. Regulation of K-Cl cotransport in erythrocytes of frog Rana temporaria by commonly used protein kinase and protein phosphatase inhibitors. J Comp Physiol B 2010; 180:385-91. [PMID: 19936761 DOI: 10.1007/s00360-009-0418-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2009] [Revised: 10/07/2009] [Accepted: 11/03/2009] [Indexed: 10/20/2022]
Abstract
Recently (Agalakova and Gusev in J Comp Physiol 179:443-450, 2009), we demonstrated that the activity of K-Cl cotransport (KCC) in frog red blood cells is inhibited under stimulation of protein kinase C (PKC) with phorbol ester PMA (12-myristate-13-acetate). Present work was performed to uncover possible implication of protein kinases and protein phosphatases (PPs) in the regulation of baseline and volume-dependent KCC activity in these cells. K+ influx was estimated as 86Rb uptake by the cells in isotonic or hypotonic media in the presence of ouabain, K+ efflux was determined as the difference between K+ loss by the cells incubated in parallel in isotonic or hypotonic K(+)-free Cl(-)- and NO(3)(-)-media. Swelling of the cells in hypotonic medium was accompanied by approximately 50% activation of Cl-dependent K+ influx and efflux. Protein tyrosine kinase (PTK) inhibitor genistein (0.1 mM) stably and considerably (up to 89%) suppressed both baseline and volume-dependent KCC activity in each direction. Other PTK blockers (tyrphostin 23 and quercetin) had no influence on KCC activity in frog erythrocytes. PKC inhibitor chelerythrine (20 microM) and both PP inhibitors, fluoride (5 mM) and okadaic acid (1 microM), reduced KCC activity by 25-70%. Neither basal nor swelling-activated KCC in frog erythrocytes was affected by PKC inhibitor staurosporine (1 microM). Based on the previous and present results, we can suggest that the main role in the maintenance of basal and volume-dependent KCC activity in frog erythrocytes belongs to PTKs and PPs, whereas PKC is a negative regulator of this ion system.
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Affiliation(s)
- Gennadii Petrovich Gusev
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, Thorez pr. 44, 194223 St. Petersburg, Russia
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Liu Y, Chen J, Song T, Hu C, Tang Y, Zhang X, Zhao J. Contribution of K+-Cl- cotransporter 2 in MK-801-induced impairment of long term potentiation. Behav Brain Res 2009; 201:300-4. [PMID: 19428648 DOI: 10.1016/j.bbr.2009.02.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2008] [Revised: 02/23/2009] [Accepted: 02/27/2009] [Indexed: 10/21/2022]
Abstract
Previous studies have indicated that GABAergic disinhibition contributes to cognitive deficits mediated by NMDA receptor hypofunction in schizophrenia model of rats. However, the underlying mechanism of GABAergic disinhibition in schizophrenia remains elusive. In this study, we found that the maintenance of long term potentiation (LTP) was impaired in the hippocampus of rats with MK-801-induced cognitive impairments. The impairment of LTP maintenance was significantly reversed by picrotoxinin, a specific GABA(A) receptor-chloride channel blocker and furosemide, a K+-Cl- cotransporter 2 (KCC2) blocker, respectively. Furthermore, immunoblotting results indicated KCC2 expression in hippocampal CA1 of MK-801-treated rats was lower than that of normal rats before LTP induction. Additionally, LTP-accompanied downregulation of KCC2 was prevented in MK-801-treated rats during LTP induction. Our results suggested that KCC2 expression in hippocampal CA1 of MK-801-treated rats was not further decreased by LTP induction because of its low expression caused by MK-801 treatment. Accordingly, GABAergic inhibition was not further decreased during LTP induction due to the depressed basal GABAergic tone in MK-801-treated rats, Therefore, GABAergic disinhibition in MK-801-treated rats restricts the further downregulation of KCC2 during LTP induction and contributes to the stable GABAergic inhibition and the impaired LTP expression. Our results thus reveal the mechanism that GABAergic disinhibition contributes to cognitive deficits.
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Affiliation(s)
- Yong Liu
- Mental Health Institute, The Second Xiangya Hospital, Central South University, 139# Renmin Middle Road, Changsha 410011, Hunan, China
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Hershfinkel M, Kandler K, Knoch ME, Dagan-Rabin M, Aras MA, Abramovitch-Dahan C, Sekler I, Aizenman E. Intracellular zinc inhibits KCC2 transporter activity. Nat Neurosci 2009; 12:725-7. [PMID: 19430470 PMCID: PMC2737597 DOI: 10.1038/nn.2316] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2009] [Accepted: 03/23/2009] [Indexed: 11/09/2022]
Abstract
We found that K(+)/Cl(-) co-transporter 2 (KCC2) activity, monitored with wide-field fluorescence, was inhibited by intracellular Zn(2+), a major component of neuronal injury. Zn(2+)-mediated KCC2 inhibition produced a depolarizing shift of GABA(A) reversal potentials in rat cortical neurons. Moreover, oxygen-glucose deprivation attenuated KCC2 activity in a Zn(2+)-dependent manner. The link between Zn(2+) and KCC2 activity provides a previously unknown target for neuroprotection and may be important in activity-dependent regulation of inhibitory synaptic transmission.
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Casula S, Zolotarev AS, Stuart-Tilley AK, Wilhelm S, Shmukler BE, Brugnara C, Alper SL. Chemical crosslinking studies with the mouse Kcc1 K-Cl cotransporter. Blood Cells Mol Dis 2009; 42:233-40. [PMID: 19380103 PMCID: PMC2797447 DOI: 10.1016/j.bcmd.2009.01.021] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2009] [Accepted: 01/06/2009] [Indexed: 10/24/2022]
Abstract
Oligomerization, function, and regulation of unmodified mouse Kcc1 K-Cl cotransporter were studied by chemical crosslinking. Treatment of Xenopus oocytes and 293T cells expressing K-Cl cotransporter Kcc1 with several types of chemical cross-linkers shifted Kcc1 polypeptide to higher molecular weight forms. More extensive studies were performed with the amine-reactive disuccinyl suberate (DSS) and with the sulfhydryl-reactive bis-maleimidohexane (BMH). Kcc1 cross-linking was time-dependent in intact oocytes, and was independent of protein concentration in detergent lysates from oocytes or 293T cells. Kcc1 cross-linking by the cleavable cross-linker DTME was reversible. The N-terminal and C-terminal cytoplasmic tails of Kcc1 were not essential for Kcc1 crosslinking. PFO-PAGE and gel filtration revealed oligomeric states of uncrosslinked KCC1 corresponding in mobility to that of cross-linked protein. DSS and BMH each inhibited KCC1-mediated (86)Rb(+) uptake stimulated by hypotonicity or by N-ethylmaleimide (NEM) without reduction in nominal surface abundance of KCC1. These data add to evidence supporting the oligomeric state of KCC polypeptides.
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Affiliation(s)
- Sabina Casula
- Molecular and Vascular Medicine, Beth Israel Deaconess Medical Center
| | - Alexander S. Zolotarev
- Molecular and Vascular Medicine, Beth Israel Deaconess Medical Center
- Dept. of Medicine, Harvard Medical School, Boston, MA
| | | | - Sabine Wilhelm
- Molecular and Vascular Medicine, Beth Israel Deaconess Medical Center
| | - Boris E. Shmukler
- Molecular and Vascular Medicine, Beth Israel Deaconess Medical Center
| | - Carlo Brugnara
- Dept. of Laboratory Medicine, The Children's Hospital, Harvard Medical School, Boston, MA
- Dept. of Pathology, Harvard Medical School, Boston, MA
| | - Seth L. Alper
- Molecular and Vascular Medicine, Beth Israel Deaconess Medical Center
- Renal Units, Beth Israel Deaconess Medical Center
- Dept. of Medicine, Harvard Medical School, Boston, MA
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Li X, Zhou J, Chen Z, Chen S, Zhu F, Zhou L. Long-term expressional changes of Na+ -K+ -Cl- co-transporter 1 (NKCC1) and K+ -Cl- co-transporter 2 (KCC2) in CA1 region of hippocampus following lithium-pilocarpine induced status epilepticus (PISE). Brain Res 2008; 1221:141-6. [PMID: 18550034 DOI: 10.1016/j.brainres.2008.04.047] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2008] [Revised: 04/13/2008] [Accepted: 04/17/2008] [Indexed: 11/17/2022]
Abstract
NKCC1 and KCC2 are encoded by slc12 gene family and involved in the maintenance of intracellular chloride concentration which may be associated with epileptogenesis. In this study, we aimed to investigate the long-term expression profiles of NKCC1 and KCC2 in CA1 region in the mice model of lithium-pilocarpine induced status epilepticus (PISE) and their relationship with epileptogenesis. We found NKCC1 mRNA and proteins were up-regulated at 1 d, 14 d and 45 d after pilocarpine injection, while KCC2 was down-regulated. According to obtained results, there were some expressional changes of NKCC1 and KCC2. Deregulation of their expression may break the balance of intracellular and extracellular chloride concentration which contributes to the mechanism of hyperexcitability leading to seizures. Also it may provide new drug targets for development of new antiepileptic medicine.
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Affiliation(s)
- Xiubin Li
- Neurological Department of the 1st Affiliated Hospital of Sun Yat-sen University, GuangZhou, 510080, PR China
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37
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Kim DY, Fenoglio KA, Simeone TA, Coons SW, Wu J, Chang Y, Kerrigan JF, Rho JM. GABAA receptor-mediated activation of L-type calcium channels induces neuronal excitation in surgically resected human hypothalamic hamartomas. Epilepsia 2008; 49:861-71. [PMID: 18076645 DOI: 10.1111/j.1528-1167.2007.01455.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
PURPOSE The human hypothalamic hamartoma (HH) is a rare, intrinsically epileptogenic lesion associated with gelastic seizures, but the underlying mechanisms remain unclear. Here, we examined the role of GABAA receptors in surgically resected HH tissue. METHODS HH tissue slices (350 microm) were studied using cellular electrophysiological, calcium imaging, and immunocytochemical techniques. RESULTS Two neuronal cell types were seen: small (10-16 microm) spontaneously firing GABAergic neurons and large (20-28 microm) quiescent neurons. In gramicidin-perforated patch recordings, muscimol (30 microM) induced membrane depolarization in 70% of large (but not small) neurons and a concomitant rise in intracellular calcium. These responses were blocked by bicuculline methiodide (50 microM). Depolarizing neurons also exhibited more positive reversal potentials (Emuscimol) and significantly higher intracellular chloride concentrations compared to those that hyperpolarized. The cation chloride co-transporters NKCC1 and KCC2 were coexpressed in the majority of large neurons, but fluorometric measurements revealed that 84% of large HH neurons expressed solely or relatively more NKCC1. Bumetanide (20 microM), a NKCC1 antagonist, partially suppressed muscimol-induced excitation in large neurons. Concordant with robust expression of CaV1.2 and CaV1.3 subunits in HH neurons, the L-type calcium channel blocker nifedipine (100 microM) prevented muscimol-induced neuronal excitation. CONCLUSIONS GABAA receptor-mediated excitation, due in part to differential expression of NKCC1 and KCC2 and subsequent activation of L-type calcium channels, may contribute to seizure genesis in HH tissue. Given the ready availability of L-type calcium channel blockers, our results have clinical ramifications for the treatment of seizures associated with HH lesions.
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MESH Headings
- Action Potentials/drug effects
- Action Potentials/physiology
- Adolescent
- Adult
- Calcium Channels, L-Type/drug effects
- Calcium Channels, L-Type/metabolism
- Calcium Channels, L-Type/physiology
- Child, Preschool
- Chloride Channels/metabolism
- Epilepsies, Partial/metabolism
- Epilepsies, Partial/physiopathology
- Female
- Hamartoma/metabolism
- Hamartoma/physiopathology
- Hamartoma/surgery
- Humans
- Hypothalamic Diseases/metabolism
- Hypothalamic Diseases/physiopathology
- Hypothalamic Diseases/surgery
- Immunohistochemistry
- Infant
- Male
- Membrane Potentials/drug effects
- Membrane Potentials/physiology
- Models, Neurological
- Muscimol/pharmacology
- Neurons/drug effects
- Neurons/metabolism
- Neurons/physiology
- Nifedipine/pharmacology
- Patch-Clamp Techniques
- Receptors, GABA-A/drug effects
- Receptors, GABA-A/metabolism
- Receptors, GABA-A/physiology
- Sodium-Potassium-Chloride Symporters/metabolism
- Solute Carrier Family 12, Member 2
- Symporters/drug effects
- Symporters/metabolism
- K Cl- Cotransporters
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Affiliation(s)
- Do Young Kim
- Division of Pediatric Neurology, Barrow Neurological Institute, St. Joseph's Hospital & Medical Center, Phoenix, AZ 85013, USA
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38
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Willhauck MJ, Sharif-Samani B, Senekowitsch-Schmidtke R, Wunderlich N, Göke B, Morris JC, Spitzweg C. Functional sodium iodide symporter expression in breast cancer xenografts in vivo after systemic treatment with retinoic acid and dexamethasone. Breast Cancer Res Treat 2007; 109:263-72. [PMID: 17636401 DOI: 10.1007/s10549-007-9646-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2007] [Accepted: 06/07/2007] [Indexed: 10/23/2022]
Abstract
CONTEXT The sodium iodide symporter (NIS) mediates iodide uptake in the thyroid gland as well as in lactating breast, and is also expressed in the majority of breast cancers. Recently, we have reported stimulation of all-trans retinoic acid (atRA)-induced NIS expression in the human breast cancer cell line MCF-7 by dexamethasone (Dex), resulting in an enhanced therapeutic effect of (131)I in vitro. OBJECTIVE In the current study we examined the efficacy of Dex stimulation of atRA-induced NIS expression in vivo in MCF-7 xenotransplants in nude mice. DESIGN After systemic treatment with atRA alone or in combination with Dex, iodide accumulation in the tumors was assessed by gamma camera imaging and gamma counter analysis. In addition, NIS expression was examined on RNA and protein level by RT-PCR and immunohistochemistry, respectively. RESULTS Using gamma camera imaging after intraperitoneal injection of 18.5 MBq (123)I, no iodide accumulation was detected in tumors of untreated mice or mice treated with atRA only. After combined treatment with atRA/Dex significant (123)I accumulation was detected in MCF-7 xenografts, which, by ex vivo gamma counting revealed a 3.3-fold increase in iodide accumulation as compared to control tumors. Surprisingly, in a subset of mice treated with atRA or atRA/Dex iodide accumulation was also detected in the normal mammary glands. In a normal human mammary epithelial cell line HB-2, however, no functional NIS expression was induced after treatment with atRA and/or Dex in vitro. Further, NIS mRNA and protein expression was detected in atRA/Dex treated MCF-7 tumors by RT-PCR and immunohistochemistry, respectively. CONCLUSION Treatment with Dex in the presence of atRA is able to induce significant amounts of iodide accumulation in breast cancer xenotransplants in vivo due to stimulation of functional NIS protein expression, which opens exciting perspectives for a possible diagnostic and therapeutic role of radioiodine in the treatment of breast cancer.
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Affiliation(s)
- Michael J Willhauck
- Department of Internal Medicine II, Ludwig-Maximilians-University, Munich, Germany
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39
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Takahashi R, Nishio T, Ichizen N, Takano T. Cloning and functional analysis of the K+ transporter, PhaHAK2, from salt-sensitive and salt-tolerant reed plants. Biotechnol Lett 2007; 29:501-6. [PMID: 17279448 DOI: 10.1007/s10529-006-9246-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2006] [Revised: 10/24/2006] [Accepted: 10/25/2006] [Indexed: 11/30/2022]
Abstract
We isolated PhaHAK2 cDNAs from salt-tolerant and salt-sensitive reed plants. PhaHAK2 belongs to group II by phylogenetic analysis, and was predicted to be a high-affinity plasma membrane K(+) transporter. Yeast transformed with the PhaHAK2-u from salt-sensitive reed plants (Phragmites australis) had a decreased ability to take up K(+) in the presence of NaCl and showed a higher Na(+) permeability than yeast transformed with PhaHAK2-n or PhaHAK2-e from two salt-tolerant reed plants. These results suggest a possibility that the continuous K(+) uptake by PhaHAK2 and maintenance of high K(+)/Na(+) ratio under salt stress condition is one of the causes of the salt-tolerance in reed plants.
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Affiliation(s)
- Ryuichi Takahashi
- Asian Natural Environmental Science Center, The University of Tokyo, Nishitokyo-shi, Tokyo, Japan
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40
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Abstract
The effects of capsaicin on intestinal cephalexin absorption were investigated by means of in situ single pass perfusion in rats to clarify whether this pungent compound present in spice is a potential factor altering the intestinal drug absorption processes. Under the control condition, cephalexin was absorbed at a rate of 1.16+/-0.08 and 0.90+/-0.06 nmol/min/cm in the jejunum and ileum, respectively. The intestinal cephalexin absorption rate was decreased when capsaicin was dissolved in the perfusate at a concentration of 400 microM, being 0.54+/-0.07 and 0.46+/-0.10 nmol/min/cm in the jejunum and ileum, respectively. The inhibitive effect of capsaicin on intestinal cephalexin absorption was diminished when ruthenium red, a non-selective inhibitor of the transient receptor potential (TRP) cation channels, was intravenously infused into the rat during the experiment. Moreover, when we evaluated the paracellular permeability of cephalexin by utilizing a competitive inhibitor, glycylsarcosine, it was demonstrated that glycylsarcosine-insensitive intestinal cephalexin absorption in the jejunum was increased by 4.5 times in the presence of 400 microM capsaicin. These findings indicate that capsaicin affects both transcellular and paracellular pathways of intestinal cephalexin absorption by interacting with the TRP cation channels in intestinal tissues, in which capsaicin seems to change the transport activity of H+/peptide co-transporter 1 (PEPT1), and to a lesser degree, it seems to alter the paracellular permeability of the intestinal epithelia.
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Affiliation(s)
- Yukiko Komori
- Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama 700-8530, Japan
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41
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Xiang J, Hu Y, Smith DE, Keep RF. PEPT2-mediated transport of 5-aminolevulinic acid and carnosine in astrocytes. Brain Res 2006; 1122:18-23. [PMID: 17034769 PMCID: PMC1829310 DOI: 10.1016/j.brainres.2006.09.013] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2006] [Revised: 09/05/2006] [Accepted: 09/06/2006] [Indexed: 11/28/2022]
Abstract
5-aminolevulinic acid (ALA) and carnosine have important physiological and pathophysiological roles in the CNS. Both are substrates for the proton-coupled oligopeptide transporter PEPT2. The purpose of the current study was to determine the importance of PEPT2 in the uptake of ALA and carnosine in rat and mouse (PEPT2+/+ and PEPT2-/-) cultured neonatal astrocytes. Although neonatal astrocytes are known to express PEPT2, its quantitative importance in the transport of these compounds is not known. [14C]ALA uptake in neonatal rat astrocytes was inhibited by dipeptides, an alpha-amino containing cephalosporin (which is a PEPT2 substrate) but was not affected by a non-amino containing cephalosporin (which is not a PEPT2 substrate). Uptake was pH sensitive as expected from a proton-coupled transporter and was saturable (Vmax=715+/-29 pmol/mg/min, Km=606+/-14 microM). [3H]Carnosine uptake in neonatal rat astrocytes was inhibited by dipeptides but not by histidine (a substrate for the peptide/histidine transporters PHT1 and PHT2) and also showed saturable transport (Vmax=447+/-23 pmol/mg/min, Km=43+/-5.5 microM). Neonatal astrocytes from PEPT2-/- mice had a 62% reduction in [14C]ALA uptake and a 92% reduction in [3H]carnosine uptake compared to PEPT2+/+ mice. These results demonstrate that PEPT2 is the primary transporter responsible for the astrocytic uptake of ALA and carnosine.
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Affiliation(s)
- Jianming Xiang
- Department of Neurosurgery, University of Michigan, 5014 BSRB, Ann Arbor, MI 48109-2200, USA.
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42
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Wang W, Xu TL. Chloride homeostasis differentially affects GABA(A) receptor- and glycine receptor-mediated effects on spontaneous circuit activity in hippocampal cell culture. Neurosci Lett 2006; 406:11-6. [PMID: 16905250 DOI: 10.1016/j.neulet.2006.06.064] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2006] [Revised: 06/28/2006] [Accepted: 06/30/2006] [Indexed: 11/27/2022]
Abstract
The potassium-chloride cotransporter 2 (KCC2)-dependent intracellular chloride level determines whether neurons respond to GABA and/or glycine by depolarization or hyperpolarization. However, still unknown is the role of KCC2-dependent chloride homeostasis in regulating the spontaneous activity of neuronal circuits via GABA(A) receptor (GABA(A)R) and the glycine receptor (GlyR). In this study, patch-clamp recordings were performed to measure the change of spontaneous neuronal activity in cultured hippocampal neurons. Our results showed that inhibition of KCC2 with furosemide, as well as blockade of GABA(A)R with bicuculline, significantly enhanced circuit activity. Perfusion with bicuculline further enhanced the effects of furosemide on spontaneous circuit activity, while furosemide did not alter the effects of bicuculline. Surprisingly, blockade of GlyR not only induced obvious tonic currents, but also significantly decreased spontaneous synaptic activity. Moreover, inhibition of KCC2 did not change the depressive effect of strychnine on neuronal circuits. Our findings suggest that KCC2-dependent chloride homeostasis is mainly involved in GABA(A)R-mediated synaptic inhibition whereas GlyR-mediated tonic action plays a totally different role in regulating hippocampal circuit activity.
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Affiliation(s)
- Wei Wang
- Department of Neurobiology and Biophysics, School of Life Sciences, University of Science and Technology of China, Hefei 230027, China
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43
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Abstract
The sodium/iodide symporter (NIS) mediates iodide uptake in the thyroid gland and lactating breast. NIS mRNA and protein expression are detected in most thyroid cancer specimens, although functional iodide uptake is usually reduced resulting in the characteristic finding of a 'cold' or non-functioning lesion on a radioiodine image. Iodide uptake after thyroid stimulating hormone (TSH) stimulation, however, is sufficient in most differentiated thyroid cancer to utilize beta-emitting radioactive iodide for the treatment of residual and metastatic disease. Elevated serum TSH, achieved by thyroid hormone withdrawal in athyreotic patients or after recombinant human thyrotropin administration, directly stimulates NIS gene expression and/or NIS trafficking to the plasma membrane, increasing radioiodide uptake. Approximately 10-20% differentiated thyroid cancers, however, do not express the NIS gene despite TSH stimulation. These tumors are generally associated with a poor prognosis. Reduced NIS gene expression in thyroid cancer is likely due in part, to impaired trans-activation at the proximal promoter and/or the upstream enhancer. Basal NIS gene expression is detected in about 80% breast cancer specimens, but the fraction with functional iodide transport is relatively low. Lactogenic hormones and various nuclear hormone receptor ligands increase iodide uptake in breast cancer cells in vitro, but TSH has no effect. A wide range of 'differentiation' agents have been utilized to stimulate NIS expression in thyroid and breast cancer using in vitro and in vivo models, and a few have been used in clinical studies. Retinoic acid has been used to stimulate NIS expression in both thyroid and breast cancer. There are similarities and differences in NIS gene regulation and expression in thyroid and breast cancer. The various agents used to enhance NIS expression in thyroid and breast cancer will be reviewed with a focus on the mechanism of action. Agents that promote tumor differentiation, or directly stimulate NIS gene expression, may result in iodine concentration in 'scan-negative' thyroid cancer and some breast cancer.
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Affiliation(s)
- T Kogai
- Molecular Endocrinology Laboratory, VA Greater Los Angeles Healthcare System, Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California 90073, USA
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44
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Biegel A, Knütter I, Hartrodt B, Gebauer S, Theis S, Luckner P, Kottra G, Rastetter M, Zebisch K, Thondorf I, Daniel H, Neubert K, Brandsch M. The renal type H+/peptide symporter PEPT2: structure-affinity relationships. Amino Acids 2006; 31:137-56. [PMID: 16868651 DOI: 10.1007/s00726-006-0331-0] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2005] [Accepted: 01/04/2006] [Indexed: 10/24/2022]
Abstract
The H(+)/peptide cotransporter PEPT2 is expressed in a variety of organs including kidney, lung, brain, mammary gland, and eye. PEPT2 substrates are di- and tripeptides as well as peptidomimetics, such as beta-lactam antibiotics. Due to the presence of PEPT2 at the bronchial epithelium, the aerosolic administration of peptide-like drugs might play a major role in future treatment of various pulmonary and systemic diseases. Moreover, PEPT2 has a significant influence on the in vivo disposition and half-life time of peptide-like drugs within the body, particularly in kidney and brain. PEPT2 is known to have similar but not identical structural requirements for substrate recognition and transport compared to PEPT1, its intestinal counterpart. In this review we compiled available affinity constants of 352 compounds, measured at different mammalian tissues and expression systems and compare the data whenever possible with those of PEPT1.
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Affiliation(s)
- A Biegel
- Institute of Biochemistry, Department of Biochemistry/Biotechnology, Martin-Luther-University Halle-Wittenberg, Halle, Germany
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45
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Abstract
The proton coupled amino acid transporter PAT1 expressed in intestine, brain, and other organs accepts L- and D-proline, glycine, and L-alanine but also pharmaceutically active amino acid derivatives such as 3-amino-1-propanesulfonic acid, L-azetidine-2-carboxylic acid, and cis-4-hydroxy-D-proline as substrates. We systematically analyzed the structural requirements for PAT1 substrates by testing 87 amino acids, proline homologs, indoles, and derivatives. Affinity data and effects on membrane potential were determined using Caco-2 cells. For aliphatic amino acids, a blocked carboxyl group, the distance between amino and carboxyl group, and the position of the hydroxyl group are affinity limiting factors. Methylation of the amino group enhances substrate affinity. Hetero atoms in the proline template are well tolerated. Aromatic alpha-amino acids display low affinity. PAT1 interacts strongly with heterocyclic aromatic acids containing an indole scaffold. The structural requirements of PAT1 substrates elucidated in this study will be useful for the development of prodrugs.
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Affiliation(s)
- L Metzner
- Membrane Transport Group, Biozentrum, Martin-Luther-University Halle-Wittenberg, Halle, Germany
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46
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Ho RH, Tirona RG, Leake BF, Glaeser H, Lee W, Lemke CJ, Wang Y, Kim RB. Drug and bile acid transporters in rosuvastatin hepatic uptake: function, expression, and pharmacogenetics. Gastroenterology 2006; 130:1793-806. [PMID: 16697742 DOI: 10.1053/j.gastro.2006.02.034] [Citation(s) in RCA: 491] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2005] [Accepted: 02/08/2006] [Indexed: 12/02/2022]
Abstract
BACKGROUND & AIMS The 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, or statins, target liver HMG-CoA and are of proven benefit in the prevention of coronary heart disease. Rosuvastatin is an effective statin notable for liver selectivity and lack of significant metabolism. We assessed the extent and relevance of hepatic transporters to rosuvastatin uptake. METHODS Transporters involved in rosuvastatin uptake were determined through heterologous expression of multiple human and rat uptake transporters. Human organic anion transporting polypeptide (OATP) 1B1 and sodium-dependent taurocholate cotransporting polypeptide (NTCP) allelic variants were also assessed. Expression of OATP and NTCP messenger RNA and protein was determined from a bank of human liver samples. RESULTS Multiple OATP family members, including 1B1, 1B3, 2B1, and 1A2, were capable of rosuvastatin transport. Naturally occurring polymorphisms in OATP1B1, including *5, *9, *15, and *18, were associated with profound loss of activity toward rosuvastatin. Interestingly, the major human hepatic bile acid uptake transporter NTCP, but not rat Ntcp, also transported rosuvastatin. Human hepatocyte studies suggested that NTCP alone accounted for approximately 35% of rosuvastatin uptake. Remarkably, NTCP*2, a variant known to have a near complete loss of function for bile acids, exhibited a profound gain of function for rosuvastatin. Quantitative messenger RNA analysis revealed marked intersubject variability in expression of OATPs and NTCP. CONCLUSIONS Multiple transporters mediate the overall hepatic uptake of rosuvastatin, and NTCP may be a heretofore unrecognized transporter important to the disposition of rosuvastatin and possibly other drugs/statins in clinical use. Accordingly, transporter expression and polymorphisms may be key determinants of intersubject variability in response to statin therapy in general.
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Affiliation(s)
- Richard H Ho
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
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47
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Yodoya E, Wada M, Shimada A, Katsukawa H, Okada N, Yamamoto A, Ganapathy V, Fujita T. Functional and molecular identification of sodium-coupled dicarboxylate transporters in rat primary cultured cerebrocortical astrocytes and neurons. J Neurochem 2006; 97:162-73. [PMID: 16524379 DOI: 10.1111/j.1471-4159.2006.03720.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Na+-coupled carboxylate transporters (NaCs) mediate the uptake of tricarboxylic acid cycle intermediates in mammalian tissues. Of these transporters, NaC3 (formerly known as Na+-coupled dicarboxylate transporter 3, NaDC3/SDCT2) and NaC2 (formerly known as Na+-coupled citrate transporter, NaCT) have been shown to be expressed in brain. There is, however, little information available on the precise distribution and function of both transporters in the CNS. In the present study, we investigated the functional characteristics of Na+-dependent succinate and citrate transport in primary cultures of astrocytes and neurons from rat cerebral cortex. Uptake of succinate was Na+ dependent, Li+ sensitive and saturable with a Michaelis constant (Kt) value of 28.4 microM in rat astrocytes. Na+ activation kinetics revealed that the Na+ to succinate stoichiometry was 3:1 and the concentration of Na+ necessary for half-maximal transport was 53 mM. Although uptake of citrate in astrocytes was also Na+ dependent and saturable, its Kt value was significantly higher (approximately 1.2 mM) than that of succinate. Unlabeled succinate (2 mM) inhibited Na+-dependent [14C]succinate (18 microM) and [14C]citrate (4.5 microM) transport completely, whereas unlabeled citrate inhibited Na+-dependent [14C]succinate uptake more weakly. Interestingly, N-acetyl-L-aspartate, which is the second most abundant amino acid in the nervous system, also completely inhibited Na+-dependent succinate transport in rat astrocytes. The inhibition constant (Ki) for the inhibition of [14C]succinate uptake by unlabeled succinate, N-acetyl-L-aspartate and citrate was 15.9, 155 and 764 microM respectively. In primary cultures of neurons, uptake of citrate was also Na+ dependent and saturable with a Kt value of 16.2 microM, which was different from that observed in astrocytes, suggesting that different Na+-dependent citrate transport systems are expressed in neurons and astrocytes. RT-PCR and immunocytochemistry revealed that NaC3 and NaC2 are expressed in cerebrocortical astrocytes and neurons respectively. These results are in good agreement with our previous reports on the brain distribution pattern of NaC2 and NaC3 mRNA using in situ hybridization. This is the first report of the differential expression of different NaCs in astrocytes and neurons. These transporters might play important roles in the trafficking of tricarboxylic acid cycle intermediates and related metabolites between glia and neurons.
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Affiliation(s)
- Etsuo Yodoya
- Department of Biopharmaceutics, Kyoto Pharmaceutical University, Yamashina-ku, Kyoto, Japan
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48
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Murray CM, Hutchinson R, Bantick JR, Belfield GP, Benjamin AD, Brazma D, Bundick RV, Cook ID, Craggs RI, Edwards S, Evans LR, Harrison R, Holness E, Jackson AP, Jackson CG, Kingston LP, Perry MWD, Ross ARJ, Rugman PA, Sidhu SS, Sullivan M, Taylor-Fishwick DA, Walker PC, Whitehead YM, Wilkinson DJ, Wright A, Donald DK. Monocarboxylate transporter MCT1 is a target for immunosuppression. Nat Chem Biol 2006; 1:371-6. [PMID: 16370372 DOI: 10.1038/nchembio744] [Citation(s) in RCA: 194] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Current immunosuppressive therapies act on T lymphocytes by modulation of cytokine production, modulation of signaling pathways or by inhibition of the enzymes of nucleotide biosynthesis. We have identified a previously unknown series of immunomodulatory compounds that potently inhibit human and rat T lymphocyte proliferation in vitro and in vivo in immune-mediated animal models of disease, acting by a novel mechanism. Here we identify the target of these compounds, the monocarboxylate transporter MCT1 (SLC16A1), using a strategy of photoaffinity labeling and proteomic characterization. We show that inhibition of MCT1 during T lymphocyte activation results in selective and profound inhibition of the extremely rapid phase of T cell division essential for an effective immune response. MCT1 activity, however, is not required for many stages of lymphocyte activation, such as cytokine production, or for most normal physiological functions. By pursuing a chemistry-led target identification strategy, we have discovered that MCT1 is a previously unknown target for immunosuppressive therapy and have uncovered an unsuspected role for MCT1 in immune biology.
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Affiliation(s)
- Clare M Murray
- Department of Discovery BioScience, AstraZeneca R&D Charnwood, Bakewell Road, Loughborough, Leicestershire LE11 5RH, UK
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Inoue M, Terada T, Okuda M, Inui KI. Regulation of human peptide transporter 1 (PEPT1) in gastric cancer cells by anticancer drugs. Cancer Lett 2005; 230:72-80. [PMID: 16253763 DOI: 10.1016/j.canlet.2004.12.023] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2004] [Revised: 12/15/2004] [Accepted: 12/18/2004] [Indexed: 10/25/2022]
Abstract
Human peptide transporter 1 (PEPT1) mediates the cellular uptake of di- and tripeptides and peptide-like drugs in the small intestine. In the present study, we examined the regulation of PEPT1 by anticancer drugs in the gastric cancer cell line MKN45. PEPT1 was expressed and functioned in MKN45 cells. The transport activity and mRNA expression of the facilitative glucose transporter 1 (GLUT1) were significantly decreased by 5-fluorouracil treatment, but those of PEPT1 were slightly increased. Cisplatin treatment affected neither PEPT1 nor GLUT1 activity. In conclusion, PEPT1 expressed in MKN45 cells are resistant against the cellular injury induced by 5-fluorouracil and cisplatin.
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Affiliation(s)
- Mayumi Inoue
- Department of Pharmacy, Faculty of Medicine, Kyoto University Hospital, Kyoto University, Sakyo-ku, Kyoto 606-8507, Japan
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Maeda K, Kambara M, Tian Y, Hofmann AF, Sugiyama Y. Uptake of Ursodeoxycholate and Its Conjugates by Human Hepatocytes: Role of Na+-Taurocholate Cotransporting Polypeptide (NTCP), Organic Anion Transporting Polypeptide (OATP) 1B1 (OATP-C), and OATP1B3 (OATP8). Mol Pharm 2005; 3:70-7. [PMID: 16686371 DOI: 10.1021/mp050063u] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Ursodeoxycholate (UDCA) is widely used for the treatment of cholestatic liver disease. After oral administration, UDCA is absorbed, taken up efficiently by hepatocytes, and conjugated mainly with glycine to form glycoursodeoxycholate (GUDC) or partly with taurine to form tauroursodeoxycholate (TUDC), which undergo enterohepatic circulation. In this study, to check whether three basolateral transporters--Na(+)-taurocholate cotransporting polypeptide (NTCP, SLC10A1), organic anion transporting polypeptide (OATP) 1B1 (OATP-C), and OATP1B3 (OATP8)-mediate uptake of UDCA, GUDC, and TUDC by human hepatocytes, we investigated their transport properties using transporter-expressing HEK293 cells and human cryopreserved hepatocytes. TUDC and GUDC could be taken up via human NTCP, OATP1B1, and OATP1B3, whereas UDCA could be transported significantly by NTCP, but not OATP1B1 and OATP1B3 in our expression systems. We observed a time-dependent and saturable uptake of UDCA and its conjugates by human cryopreserved hepatocytes, and more than half of the overall uptake involved a saturable component. Kinetic analyses revealed that the contribution of Na(+)-dependent and -independent pathways to the uptake of UDCA or TUDC was very similar, while the Na(+)-independent uptake of GUDC was predominant. These results suggest that UDCA and its conjugates are taken up by both multiple saturable transport systems and nonsaturable transport in human liver with different contributions. These results provide an explanation for the efficient hepatic clearance of UDCA and its conjugates in patients receiving UDCA therapy.
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Affiliation(s)
- Kazuya Maeda
- Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan
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