1
|
Moreno SIG, Limani F, Ludwig I, Gilbert C, Pifl C, Hnasko TS, Steinkellner T. Viral overexpression of human alpha-synuclein in mouse substantia nigra dopamine neurons results in hyperdopaminergia but no neurodegeneration. bioRxiv 2024:2024.05.03.592188. [PMID: 38746104 PMCID: PMC11092628 DOI: 10.1101/2024.05.03.592188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Loss of select neuronal populations such as midbrain dopamine (DA) neurons is a pathological hallmark of Parkinson's disease (PD). The small neuronal protein α-synuclein has been related both genetically and neuropathologically to PD, yet how it contributes to selective vulnerability remains elusive. Here, we describe the generation of a novel adeno-associated viral vector (AAV) for Cre-dependent overexpression of wild-type human α-synuclein. Our strategy allows us to restrict α-synuclein to select neuronal populations and hence investigate the cell-autonomous effects of elevated α-synuclein in genetically-defined cell types. Since DA neurons in the substantia nigra pars compacta (SNc) are particularly vulnerable in PD, we investigated in more detail the effects of increased α-synuclein in these cells. AAV-mediated overexpression of wildtype human α-synuclein in SNc DA neurons increased the levels of α-synuclein within these cells and augmented phosphorylation of α-synuclein at serine-129, which is considered a pathological feature of PD and other synucleinopathies. However, despite abundant α-synuclein overexpression and hyperphosphorylation we did not observe any DA neurodegeneration up to 90 days post virus infusion. In contrast, we noticed that overexpression of α-synuclein resulted in increased locomotor activity and elevated striatal DA levels suggesting that α-synuclein enhanced dopaminergic activity. We therefore conclude that cell-autonomous effects of elevated α-synuclein are not sufficient to trigger acute DA neurodegeneration.
Collapse
|
2
|
Kalaba P, Pacher K, Neill PJ, Dragacevic V, Zehl M, Wackerlig J, Kirchhofer M, Sartori SB, Gstach H, Kouhnavardi S, Fabisikova A, Pillwein M, Monje-Quiroga F, Ebner K, Prado-Roller A, Singewald N, Urban E, Langer T, Pifl C, Lubec J, Leban JJ, Lubec G. Chirality Matters: Fine-Tuning of Novel Monoamine Reuptake Inhibitors Selectivity through Manipulation of Stereochemistry. Biomolecules 2023; 13:1415. [PMID: 37759815 PMCID: PMC10527105 DOI: 10.3390/biom13091415] [Citation(s) in RCA: 0] [Impact Index Per Article: 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: 07/07/2023] [Revised: 08/21/2023] [Accepted: 09/13/2023] [Indexed: 09/29/2023] Open
Abstract
The high structural similarity, especially in transmembrane regions, of dopamine, norepinephrine, and serotonin transporters, as well as the lack of all crystal structures of human isoforms, make the specific targeting of individual transporters rather challenging. Ligand design itself is also rather limited, as many chemists, fully aware of the synthetic and analytical challenges, tend to modify lead compounds in a way that reduces the number of chiral centers and hence limits the potential chemical space of synthetic ligands. We have previously shown that increasing molecular complexity by introducing additional chiral centers ultimately leads to more selective and potent dopamine reuptake inhibitors. Herein, we significantly extend our structure-activity relationship of dopamine transporter-selective ligands and further demonstrate how stereoisomers of defined absolute configuration may fine-tune and direct the activity towards distinct targets. From the pool of active compounds, using the examples of stereoisomers 7h and 8h, we further showcase how in vitro activity significantly differs in in vivo drug efficacy experiments, calling for proper validation of individual stereoisomers in animal studies. Furthermore, by generating a large library of compounds with defined absolute configurations, we lay the groundwork for computational chemists to further optimize and rationally design specific monoamine transporter reuptake inhibitors.
Collapse
Affiliation(s)
- Predrag Kalaba
- Department of Pharmaceutical Sciences, Faculty of Life Sciences, University of Vienna, 1090 Vienna, Austria; (P.K.); (K.P.); (P.J.N.); (V.D.); (J.W.); (M.K.); (H.G.); (S.K.); (M.P.); (E.U.); (T.L.)
| | - Katharina Pacher
- Department of Pharmaceutical Sciences, Faculty of Life Sciences, University of Vienna, 1090 Vienna, Austria; (P.K.); (K.P.); (P.J.N.); (V.D.); (J.W.); (M.K.); (H.G.); (S.K.); (M.P.); (E.U.); (T.L.)
| | - Philip John Neill
- Department of Pharmaceutical Sciences, Faculty of Life Sciences, University of Vienna, 1090 Vienna, Austria; (P.K.); (K.P.); (P.J.N.); (V.D.); (J.W.); (M.K.); (H.G.); (S.K.); (M.P.); (E.U.); (T.L.)
| | - Vladimir Dragacevic
- Department of Pharmaceutical Sciences, Faculty of Life Sciences, University of Vienna, 1090 Vienna, Austria; (P.K.); (K.P.); (P.J.N.); (V.D.); (J.W.); (M.K.); (H.G.); (S.K.); (M.P.); (E.U.); (T.L.)
| | - Martin Zehl
- Mass Spectrometry Centre, Faculty of Chemistry, University of Vienna, Währinger Straße 38, 1090 Vienna, Austria; (M.Z.); (A.F.)
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 38, 1090 Vienna, Austria
| | - Judith Wackerlig
- Department of Pharmaceutical Sciences, Faculty of Life Sciences, University of Vienna, 1090 Vienna, Austria; (P.K.); (K.P.); (P.J.N.); (V.D.); (J.W.); (M.K.); (H.G.); (S.K.); (M.P.); (E.U.); (T.L.)
| | - Michael Kirchhofer
- Department of Pharmaceutical Sciences, Faculty of Life Sciences, University of Vienna, 1090 Vienna, Austria; (P.K.); (K.P.); (P.J.N.); (V.D.); (J.W.); (M.K.); (H.G.); (S.K.); (M.P.); (E.U.); (T.L.)
| | - Simone B. Sartori
- Department of Pharmacology and Toxicology, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), Leopold Franzens University Innsbruck, 6020 Innsbruck, Austria; (S.B.S.); (K.E.); (N.S.)
| | - Hubert Gstach
- Department of Pharmaceutical Sciences, Faculty of Life Sciences, University of Vienna, 1090 Vienna, Austria; (P.K.); (K.P.); (P.J.N.); (V.D.); (J.W.); (M.K.); (H.G.); (S.K.); (M.P.); (E.U.); (T.L.)
| | - Shima Kouhnavardi
- Department of Pharmaceutical Sciences, Faculty of Life Sciences, University of Vienna, 1090 Vienna, Austria; (P.K.); (K.P.); (P.J.N.); (V.D.); (J.W.); (M.K.); (H.G.); (S.K.); (M.P.); (E.U.); (T.L.)
| | - Anna Fabisikova
- Mass Spectrometry Centre, Faculty of Chemistry, University of Vienna, Währinger Straße 38, 1090 Vienna, Austria; (M.Z.); (A.F.)
| | - Matthias Pillwein
- Department of Pharmaceutical Sciences, Faculty of Life Sciences, University of Vienna, 1090 Vienna, Austria; (P.K.); (K.P.); (P.J.N.); (V.D.); (J.W.); (M.K.); (H.G.); (S.K.); (M.P.); (E.U.); (T.L.)
| | - Francisco Monje-Quiroga
- Center for Physiology and Pharmacology, Department of Neurophysiology and Neuropharmacology, Medical University of Vienna, 1090 Vienna, Austria;
| | - Karl Ebner
- Department of Pharmacology and Toxicology, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), Leopold Franzens University Innsbruck, 6020 Innsbruck, Austria; (S.B.S.); (K.E.); (N.S.)
| | - Alexander Prado-Roller
- X-ray Structure Analysis Centre, Faculty of Chemistry, University of Vienna, 1090 Vienna, Austria;
| | - Nicolas Singewald
- Department of Pharmacology and Toxicology, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), Leopold Franzens University Innsbruck, 6020 Innsbruck, Austria; (S.B.S.); (K.E.); (N.S.)
| | - Ernst Urban
- Department of Pharmaceutical Sciences, Faculty of Life Sciences, University of Vienna, 1090 Vienna, Austria; (P.K.); (K.P.); (P.J.N.); (V.D.); (J.W.); (M.K.); (H.G.); (S.K.); (M.P.); (E.U.); (T.L.)
| | - Thierry Langer
- Department of Pharmaceutical Sciences, Faculty of Life Sciences, University of Vienna, 1090 Vienna, Austria; (P.K.); (K.P.); (P.J.N.); (V.D.); (J.W.); (M.K.); (H.G.); (S.K.); (M.P.); (E.U.); (T.L.)
| | - Christian Pifl
- Center for Brain Research, Medical University of Vienna, 1090 Vienna, Austria;
| | - Jana Lubec
- Programme for Proteomics, Paracelsus Medical University, 5020 Salzburg, Austria; (J.L.); (J.J.L.)
| | - Johann Jakob Leban
- Programme for Proteomics, Paracelsus Medical University, 5020 Salzburg, Austria; (J.L.); (J.J.L.)
| | - Gert Lubec
- Programme for Proteomics, Paracelsus Medical University, 5020 Salzburg, Austria; (J.L.); (J.J.L.)
| |
Collapse
|
3
|
Pifl C, Reither H, Attems J, Zecca L. Dopamine and vesicular monoamine transport loss supports incidental Lewy body disease as preclinical idiopathic Parkinson. NPJ Parkinsons Dis 2023; 9:89. [PMID: 37322038 DOI: 10.1038/s41531-023-00514-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 04/27/2023] [Indexed: 06/17/2023] Open
Abstract
Incidental Lewy body disease (ILBD) is a neuropathological diagnosis of brains with Lewy bodies without clinical neuropsychiatric symptoms. Dopaminergic deficits suggest a relationship to preclinical Parkinson's disease (PD). We now report a subregional pattern of striatal dopamine loss in ILBD cases, with dopamine found significantly decreased in the putamen (-52%) and only to a lower extent in the caudate (-38%, not statistically significant); this is similar to the pattern in idiopathic PD in various neurochemical and in vivo imaging studies. We aimed to find out if our recently reported impaired storage of dopamine in striatal synaptic vesicles prepared from striatal tissue of cases with idiopathic PD might be an early or even causative event. We undertook parallel measurements of [3H]dopamine uptake and vesicular monoamine transporter (VMAT)2 binding sites by the specific label [3H]dihydrotetrabenazine on vesicular preparation from caudate and putamen in ILBD. Neither specific uptake of dopamine and binding of [3H]dihydrotetrabenazine, nor mean values of the calculated ratios of dopamine uptake and VMAT2 binding, a measure of uptake rate per transport site, were significantly different between ILBD and controls. ATP-dependence of [3H]dopamine uptake revealed significantly higher rates in putamen than in caudate at saturating concentrations of ATP in controls, a subregional difference lost in ILBD. Our findings support a loss of the normally higher VMAT2 activity in putamen as a contributing factor to the higher susceptibility of the putamen to dopamine depletion in idiopathic PD. Moreover, we suggest ILBD postmortem tissue as a valuable source for testing hypotheses on processes in idiopathic PD.
Collapse
Affiliation(s)
- Christian Pifl
- Center for Brain Research, Medical University of Vienna, Vienna, Austria.
| | - Harald Reither
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Johannes Attems
- Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Luigi Zecca
- Institute of Biomedical Technologies, National Research Council of Italy, Segrate, Milan, Italy
| |
Collapse
|
4
|
Cronin SJF, Yu W, Hale A, Licht-Mayer S, Crabtree MJ, Korecka JA, Tretiakov EO, Sealey-Cardona M, Somlyay M, Onji M, An M, Fox JD, Turnes BL, Gomez-Diaz C, da Luz Scheffer D, Cikes D, Nagy V, Weidinger A, Wolf A, Reither H, Chabloz A, Kavirayani A, Rao S, Andrews N, Latremoliere A, Costigan M, Douglas G, Freitas FC, Pifl C, Walz R, Konrat R, Mahad DJ, Koslov AV, Latini A, Isacson O, Harkany T, Hallett PJ, Bagby S, Woolf CJ, Channon KM, Je HS, Penninger JM. Crucial neuroprotective roles of the metabolite BH4 in dopaminergic neurons. bioRxiv 2023:2023.05.08.539795. [PMID: 37214873 PMCID: PMC10197517 DOI: 10.1101/2023.05.08.539795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Dopa-responsive dystonia (DRD) and Parkinson's disease (PD) are movement disorders caused by the dysfunction of nigrostriatal dopaminergic neurons. Identifying druggable pathways and biomarkers for guiding therapies is crucial due to the debilitating nature of these disorders. Recent genetic studies have identified variants of GTP cyclohydrolase-1 (GCH1), the rate-limiting enzyme in tetrahydrobiopterin (BH4) synthesis, as causative for these movement disorders. Here, we show that genetic and pharmacological inhibition of BH4 synthesis in mice and human midbrain-like organoids accurately recapitulates motor, behavioral and biochemical characteristics of these human diseases, with severity of the phenotype correlating with extent of BH4 deficiency. We also show that BH4 deficiency increases sensitivities to several PD-related stressors in mice and PD human cells, resulting in worse behavioral and physiological outcomes. Conversely, genetic and pharmacological augmentation of BH4 protects mice from genetically- and chemically induced PD-related stressors. Importantly, increasing BH4 levels also protects primary cells from PD-affected individuals and human midbrain-like organoids (hMLOs) from these stressors. Mechanistically, BH4 not only serves as an essential cofactor for dopamine synthesis, but also independently regulates tyrosine hydroxylase levels, protects against ferroptosis, scavenges mitochondrial ROS, maintains neuronal excitability and promotes mitochondrial ATP production, thereby enhancing mitochondrial fitness and cellular respiration in multiple preclinical PD animal models, human dopaminergic midbrain-like organoids and primary cells from PD-affected individuals. Our findings pinpoint the BH4 pathway as a key metabolic program at the intersection of multiple protective mechanisms for the health and function of midbrain dopaminergic neurons, identifying it as a potential therapeutic target for PD.
Collapse
Affiliation(s)
- Shane J F Cronin
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Weonjin Yu
- Signature Program in Neuroscience and Behavioural Disorders, Duke-National University of Singapore (NUS) Medical School, 8 College Road, Singapore, 169857, Singapore
| | - Ashley Hale
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, UK
| | - Simon Licht-Mayer
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Mark J Crabtree
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, UK
| | - Joanna A Korecka
- Neurodegeneration Research Institute, Harvard Medical School/McLean Hospital, Belmont, MA, 02478, USA
| | - Evgenii O Tretiakov
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Marco Sealey-Cardona
- Department of Structural and Computational Biology, Max Perutz Labs, Vienna Biocenter Campus 5, 1030, Vienna, Austria
| | - Mate Somlyay
- Department of Structural and Computational Biology, Max Perutz Labs, Vienna Biocenter Campus 5, 1030, Vienna, Austria
| | - Masahiro Onji
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Meilin An
- Department of Medical Genetics, Life Sciences Institute, University of British Columbia, Vancouver, Canada
| | - Jesse D Fox
- Department of Medical Genetics, Life Sciences Institute, University of British Columbia, Vancouver, Canada
| | - Bruna Lenfers Turnes
- FM Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA and Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Carlos Gomez-Diaz
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Débora da Luz Scheffer
- LABOX, Departamento de Bioquímica, Universidade Federal de Santa Catarina, Florianópolis, SC 88037-100, Brazil
| | - Domagoj Cikes
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Vanja Nagy
- Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases (LBI-RUD); Department of Neurology, Medical University of Vienna (MUW), 1090 Vienna, Austria
| | - Adelheid Weidinger
- Ludwig Boltzmann Institute for Traumatology. The Research Center in Cooperation with AUVA, Donaueschingen Str. 13, 1200 Vienna, Austria
| | - Alexandra Wolf
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Harald Reither
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Antoine Chabloz
- Department of Medical Genetics, Life Sciences Institute, University of British Columbia, Vancouver, Canada
| | - Anoop Kavirayani
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Shuan Rao
- Department of Thoracic Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Nick Andrews
- FM Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA and Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Alban Latremoliere
- Neurosurgery Department, Neurosurgery Pain Research Institute, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Michael Costigan
- FM Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA and Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Gillian Douglas
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, UK
| | | | - Christian Pifl
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Roger Walz
- Center for Applied Neurocience, Universidade Federal de Santa Catarina (UFSC), Florianópolis, Brazil; Neurology Division, Internal Medicine Department, University Hospital of UFSC, Florianópolis, Brazil
| | - Robert Konrat
- Department of Structural and Computational Biology, Max Perutz Labs, Vienna Biocenter Campus 5, 1030, Vienna, Austria
| | - Don J Mahad
- Centre for Clinical Brain Sciences, University of Edinburgh, Chancellor's Building, 49 Little France Crescent, Edinburgh, EH16 4SB, UK
| | - Andrey V Koslov
- Ludwig Boltzmann Institute for Traumatology. The Research Center in Cooperation with AUVA, Donaueschingen Str. 13, 1200 Vienna, Austria
| | - Alexandra Latini
- LABOX, Departamento de Bioquímica, Universidade Federal de Santa Catarina, Florianópolis, SC 88037-100, Brazil
| | - Ole Isacson
- Neurodegeneration Research Institute, Harvard Medical School/McLean Hospital, Belmont, MA, 02478, USA
| | - Tibor Harkany
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
- Department of Neuroscience, Biomedicum 7D, Karolinska Institute, Solna, Sweden
| | - Penelope J Hallett
- Neurodegeneration Research Institute, Harvard Medical School/McLean Hospital, Belmont, MA, 02478, USA
| | - Stefan Bagby
- Department of Biology and Biochemistry and the Milner Centre for Evolution, University of Bath, Bath, UK
| | - Clifford J Woolf
- FM Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA and Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Keith M Channon
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, UK
| | - Hyunsoo Shawn Je
- Signature Program in Neuroscience and Behavioural Disorders, Duke-National University of Singapore (NUS) Medical School, 8 College Road, Singapore, 169857, Singapore
| | - Josef M Penninger
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
- Department of Medical Genetics, Life Sciences Institute, University of British Columbia, Vancouver, Canada
| |
Collapse
|
5
|
Dorninger F, Kiss A, Rothauer P, Stiglbauer-Tscholakoff A, Kummer S, Fallatah W, Perera-Gonzalez M, Hamza O, König T, Bober MB, Cavallé-Garrido T, Braverman NE, Forss-Petter S, Pifl C, Bauer J, Bittner RE, Helbich TH, Podesser BK, Todt H, Berger J. Overlapping and Distinct Features of Cardiac Pathology in Inherited Human and Murine Ether Lipid Deficiency. Int J Mol Sci 2023; 24:1884. [PMID: 36768204 PMCID: PMC9914995 DOI: 10.3390/ijms24031884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 11/28/2022] [Revised: 01/10/2023] [Accepted: 01/11/2023] [Indexed: 01/21/2023] Open
Abstract
Inherited deficiency in ether lipids, a subgroup of glycerophospholipids with unique biochemical and biophysical properties, evokes severe symptoms in humans resulting in a multi-organ syndrome. Mouse models with defects in ether lipid biosynthesis have widely been used to understand the pathophysiology of human disease and to study the roles of ether lipids in various cell types and tissues. However, little is known about the function of these lipids in cardiac tissue. Previous studies included case reports of cardiac defects in ether-lipid-deficient patients, but a systematic analysis of the impact of ether lipid deficiency on the mammalian heart is still missing. Here, we utilize a mouse model of complete ether lipid deficiency (Gnpat KO) to accomplish this task. Similar to a subgroup of human patients with rhizomelic chondrodysplasia punctata (RCDP), a fraction of Gnpat KO fetuses present with defects in ventricular septation, presumably evoked by a developmental delay. We did not detect any signs of cardiomyopathy but identified increased left ventricular end-systolic and end-diastolic pressure in middle-aged ether-lipid-deficient mice. By comprehensive electrocardiographic characterization, we consistently found reduced ventricular conduction velocity, as indicated by a prolonged QRS complex, as well as increased QRS and QT dispersion in the Gnpat KO group. Furthermore, a shift of the Wenckebach point to longer cycle lengths indicated depressed atrioventricular nodal function. To complement our findings in mice, we analyzed medical records and performed electrocardiography in ether-lipid-deficient human patients, which, in contrast to the murine phenotype, indicated a trend towards shortened QT intervals. Taken together, our findings demonstrate that the cardiac phenotype upon ether lipid deficiency is highly heterogeneous, and although the manifestations in the mouse model only partially match the abnormalities in human patients, the results add to our understanding of the physiological role of ether lipids and emphasize their importance for proper cardiac development and function.
Collapse
Affiliation(s)
- Fabian Dorninger
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, 1090 Vienna, Austria
| | - Attila Kiss
- Center for Biomedical Research, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Peter Rothauer
- Department of Neurophysiology and Neuropharmacology, Center for Physiology and Pharmacology, Medical University of Vienna, Währingerstrasse 13a, 1090 Vienna, Austria
| | - Alexander Stiglbauer-Tscholakoff
- Department of Biomedical Imaging and Image-Guided Therapy, Division of Molecular and Structural Preclinical Imaging, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Stefan Kummer
- Neuromuscular Research Department, Center for Anatomy and Cell Biology, Medical University of Vienna, Währinger Straße 13, 1090 Vienna, Austria
| | - Wedad Fallatah
- Department of Genetic Medicine, King AbdulAziz University, Jeddah 21589, Saudi Arabia
- Department of Human Genetics and Pediatrics, Montreal Children’s Hospital, McGill University, 1001 Décarie Blvd, Montreal, QC H4A 3J1, Canada
| | - Mireia Perera-Gonzalez
- Center for Biomedical Research, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Ouafa Hamza
- Center for Biomedical Research, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Theresa König
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, 1090 Vienna, Austria
| | - Michael B. Bober
- Skeletal Dysplasia Program, Nemours Children’s Hospital, 1600 Rockland Road, Wilmington, DE 19803, USA
| | - Tiscar Cavallé-Garrido
- Department of Pediatrics, Division of Cardiology, Montreal Children’s Hospital, McGill University, 1001 Décarie Blvd, Montreal, QC H4A 3J1, Canada
| | - Nancy E. Braverman
- Department of Human Genetics and Pediatrics, Montreal Children’s Hospital, McGill University, 1001 Décarie Blvd, Montreal, QC H4A 3J1, Canada
| | - Sonja Forss-Petter
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, 1090 Vienna, Austria
| | - Christian Pifl
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, 1090 Vienna, Austria
| | - Jan Bauer
- Department of Neuroimmunology, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, 1090 Vienna, Austria
| | - Reginald E. Bittner
- Neuromuscular Research Department, Center for Anatomy and Cell Biology, Medical University of Vienna, Währinger Straße 13, 1090 Vienna, Austria
| | - Thomas H. Helbich
- Department of Biomedical Imaging and Image-Guided Therapy, Division of Molecular and Structural Preclinical Imaging, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Bruno K. Podesser
- Center for Biomedical Research, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Hannes Todt
- Department of Neurophysiology and Neuropharmacology, Center for Physiology and Pharmacology, Medical University of Vienna, Währingerstrasse 13a, 1090 Vienna, Austria
| | - Johannes Berger
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, 1090 Vienna, Austria
| |
Collapse
|
6
|
Bhat S, El-Kasaby A, Kasture A, Boytsov D, Reichelt JB, Hummel T, Sucic S, Pifl C, Freissmuth M, Sandtner W. A mechanism of uncompetitive inhibition of the serotonin transporter. eLife 2023; 12:e82641. [PMID: 36648438 PMCID: PMC9883013 DOI: 10.7554/elife.82641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 08/11/2022] [Accepted: 01/17/2023] [Indexed: 01/18/2023] Open
Abstract
The serotonin transporter (SERT/SLC6A4) is arguably the most extensively studied solute carrier (SLC). During its eponymous action - that is, the retrieval of serotonin from the extracellular space - SERT undergoes a conformational cycle. Typical inhibitors (antidepressant drugs and cocaine), partial and full substrates (amphetamines and their derivatives), and atypical inhibitors (ibogaine analogues) bind preferentially to different states in this cycle. This results in competitive or non-competitive transport inhibition. Here, we explored the action of N-formyl-1,3-bis (3,4-methylenedioxyphenyl)-prop-2-yl-amine (ECSI#6) on SERT: inhibition of serotonin uptake by ECSI#6 was enhanced with increasing serotonin concentration. Conversely, the KM for serotonin was lowered by augmenting ECSI#6. ECSI#6 bound with low affinity to the outward-facing state of SERT but with increased affinity to a potassium-bound state. Electrophysiological recordings showed that ECSI#6 preferentially interacted with the inward-facing state. Kinetic modeling recapitulated the experimental data and verified that uncompetitive inhibition arose from preferential binding of ECSI#6 to the K+-bound, inward-facing conformation of SERT. This binding mode predicted a pharmacochaperoning action of ECSI#6, which was confirmed by examining its effect on the folding-deficient mutant SERT-PG601,602AA: preincubation of HEK293 cells with ECSI#6 restored export of SERT-PG601,602AA from the endoplasmic reticulum and substrate transport. Similarly, in transgenic flies, the administration of ECSI#6 promoted the delivery of SERT-PG601,602AA to the presynaptic specialization of serotonergic neurons. To the best of our knowledge, ECSI#6 is the first example of an uncompetitive SLC inhibitor. Pharmacochaperones endowed with the binding mode of ECSI#6 are attractive, because they can rescue misfolded transporters at concentrations, which cause modest transport inhibition.
Collapse
Affiliation(s)
- Shreyas Bhat
- Institute of Pharmacology and the Gaston H. Glock Research Laboratories for Exploratory Drug Development, Center of Physiology and Pharmacology, Medical University of ViennaViennaAustria
| | - Ali El-Kasaby
- Institute of Pharmacology and the Gaston H. Glock Research Laboratories for Exploratory Drug Development, Center of Physiology and Pharmacology, Medical University of ViennaViennaAustria
| | - Ameya Kasture
- Department of Neurobiology, University of ViennaViennaAustria
| | - Danila Boytsov
- Institute of Pharmacology and the Gaston H. Glock Research Laboratories for Exploratory Drug Development, Center of Physiology and Pharmacology, Medical University of ViennaViennaAustria
| | - Julian B Reichelt
- Institute of Pharmacology and the Gaston H. Glock Research Laboratories for Exploratory Drug Development, Center of Physiology and Pharmacology, Medical University of ViennaViennaAustria
| | - Thomas Hummel
- Department of Neurobiology, University of ViennaViennaAustria
| | - Sonja Sucic
- Institute of Pharmacology and the Gaston H. Glock Research Laboratories for Exploratory Drug Development, Center of Physiology and Pharmacology, Medical University of ViennaViennaAustria
| | - Christian Pifl
- Center for Brain Research, Medical University of ViennaViennaAustria
| | - Michael Freissmuth
- Institute of Pharmacology and the Gaston H. Glock Research Laboratories for Exploratory Drug Development, Center of Physiology and Pharmacology, Medical University of ViennaViennaAustria
| | - Walter Sandtner
- Institute of Pharmacology and the Gaston H. Glock Research Laboratories for Exploratory Drug Development, Center of Physiology and Pharmacology, Medical University of ViennaViennaAustria
| |
Collapse
|
7
|
Fallatah W, Cui W, Di Pietro E, Carter GT, Pounder B, Dorninger F, Pifl C, Moser AB, Berger J, Braverman NE. A Pex7 Deficient Mouse Series Correlates Biochemical and Neurobehavioral Markers to Genotype Severity—Implications for the Disease Spectrum of Rhizomelic Chondrodysplasia Punctata Type 1. Front Cell Dev Biol 2022; 10:886316. [PMID: 35898397 PMCID: PMC9310236 DOI: 10.3389/fcell.2022.886316] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 05/19/2022] [Indexed: 12/31/2022] Open
Abstract
Rhizomelic chondrodysplasia punctata type 1 (RCDP1) is a peroxisome biogenesis disorder caused by defects in PEX7 leading to impairment in plasmalogen (Pls) biosynthesis and phytanic acid (PA) oxidation. Pls deficiency is the main pathogenic factor that determines the severity of RCDP. Severe (classic) RCDP patients have negligible Pls levels, congenital cataracts, skeletal dysplasia, growth and neurodevelopmental deficits, and cerebral hypomyelination and cerebellar atrophy on brain MRI. Individuals with milder or nonclassic RCDP have higher Pls levels, better growth and cognitive outcomes. To better understand the pathophysiology of RCDP disorders, we generated an allelic series of Pex7 mice either homozygous for the hypomorphic allele, compound heterozygous for the hypomorphic and null alleles or homozygous for the null allele. Pex7 transcript and protein were almost undetectable in the hypomorphic model, and negligible in the compound heterozygous and null mice. Pex7 deficient mice showed a graded reduction in Pls and increases in C26:0-LPC and PA in plasma and brain according to genotype. Neuropathological evaluation showed significant loss of cerebellar Purkinje cells over time and a decrease in brain myelin basic protein (MBP) content in Pex7 deficient models, with more severe effects correlating with Pex7 genotype. All Pex7 deficient mice exhibited a hyperactive behavior in the open field environment. Brain neurotransmitters analysis of Pex7 deficient mice showed a significant reduction in levels of dopamine, norepinephrine, serotonin and GABA. Also, a significant correlation was found between brain neurotransmitter levels, the hyperactivity phenotype, Pls level and the severity of Pex7 genotype. In conclusion, our study showed evidence of a genotype-phenotype correlation between the severity of Pex7 deficiency and several clinical and neurobiochemical phenotypes in RCDP1 mouse models. We propose that PA accumulation may underlie the cerebellar atrophy seen in older RCDP1 patients, as even relatively low tissue levels were strongly associated with Purkinje cells loss over time in the murine models. Also, our data demonstrate the interrelation between Pls, brain neurotransmitter deficiencies and the neurobehavioral phenotype, which could be further used as a valuable clinical endpoint for therapeutic interventions. Finally, these models show that incremental increases in Pex7 levels result in dramatic improvements in phenotype.
Collapse
Affiliation(s)
- Wedad Fallatah
- Department of Human Genetics, McGill University, Montreal, QC, Canada
- Department of Medical Genetics, King Abdul-Aziz University, Jeddah, Saudi Arabia
- *Correspondence: Wedad Fallatah, ; Nancy E. Braverman,
| | - Wei Cui
- Child Health and Human Development Program, Peroxisome Disease Laboratory, Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | - Erminia Di Pietro
- Child Health and Human Development Program, Peroxisome Disease Laboratory, Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | - Grace T. Carter
- Child Health and Human Development Program, Peroxisome Disease Laboratory, Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | - Brittany Pounder
- Child Health and Human Development Program, Peroxisome Disease Laboratory, Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | - Fabian Dorninger
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Christian Pifl
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Ann B. Moser
- Hugo W Moser Research Institute, Kennedy Krieger Institute, Baltimore, MD, United States
| | - Johannes Berger
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Nancy E. Braverman
- Department of Human Genetics, McGill University, Montreal, QC, Canada
- Child Health and Human Development Program, Peroxisome Disease Laboratory, Research Institute of the McGill University Health Centre, Montreal, QC, Canada
- *Correspondence: Wedad Fallatah, ; Nancy E. Braverman,
| |
Collapse
|
8
|
da Silva SR, Kalaba P, Fabišiková A, Zehl M, Dragačević V, Dos Anjos LR, Neill PJ, Wieder M, Prado-Roller A, Gajic N, Palaretti V, da Silva GVJ, Pifl C, Lubec G, Gonzalez ERP. Synthesis and dopamine receptor binding of dihydrexidine and SKF 38393 catecholamine-based analogues. Amino Acids 2021; 54:85-98. [PMID: 34842969 DOI: 10.1007/s00726-021-03106-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 11/17/2021] [Indexed: 10/19/2022]
Abstract
Dopamine is an important neurotransmitter that regulates numerous essential functions, including cognition and voluntary movement. As such, it serves as an important scaffold for synthesis of novel analogues as part of drug development effort to obtain drugs for treatment of neurodegenerative diseases, such as Parkinson's disease. To that end, similarity search of the ZINC database based on two known dopamine-1 receptor (D1R) agonists, dihydrexidine (DHX) and SKF 38393, respectively, was used to predict novel chemical entities with potential binding to D1R. Three compounds that showed the highest similarity index were selected for synthesis and bioactivity profiling. All main synthesis products as well as the isolated intermediates, were properly characterized. The physico-chemical analyses were performed using HRESIMS, GC/MS, LC/MS with UV-Vis detection, and FTIR, 1H NMR and 13C NMR spectroscopy. Binding to D1 and D2 receptors and inhibition of dopamine reuptake via dopamine transporter were measured for the synthesized analogues of DHX and SKF 38393.
Collapse
Affiliation(s)
- Suzane Rosa da Silva
- Laboratory of Fine Organic Chemistry, Department of Chemistry and Biochemistry, Faculty of Sciences and Technology of São Paulo State University, Presidente Prudente, São Paulo, 19060-900, Brazil
| | - Predrag Kalaba
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, Althanstraße 14, 1090, Vienna, Austria
| | - Anna Fabišiková
- Mass Spectrometry Centre, Faculty of Chemistry, University of Vienna, Währinger Straße 38, 1090, Vienna, Austria
| | - Martin Zehl
- Mass Spectrometry Centre, Faculty of Chemistry, University of Vienna, Währinger Straße 38, 1090, Vienna, Austria.,Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 38, 1090, Vienna, Austria
| | - Vladimir Dragačević
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, Althanstraße 14, 1090, Vienna, Austria
| | - Luana Ribeiro Dos Anjos
- Laboratory of Fine Organic Chemistry, Department of Chemistry and Biochemistry, Faculty of Sciences and Technology of São Paulo State University, Presidente Prudente, São Paulo, 19060-900, Brazil
| | - Philip John Neill
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, Althanstraße 14, 1090, Vienna, Austria
| | - Marcus Wieder
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, Althanstraße 14, 1090, Vienna, Austria
| | - Alexander Prado-Roller
- Centre for X-Ray Structure Analysis at Faculty of Chemistry, University of Vienna, Währinger Straße 40-42, 1090, Vienna, Austria
| | - Natalie Gajic
- Centre for X-Ray Structure Analysis at Faculty of Chemistry, University of Vienna, Währinger Straße 40-42, 1090, Vienna, Austria
| | - Vinicius Palaretti
- Department of Chemistry, Faculty of Philosophy, Sciences and Letters of Ribeirão Preto, University of São Paulo, Avenida dos Bandeirantes, 3900, Ribeirão Preto, SP, 14040-901, Brazil
| | - Gil Valdo Jose da Silva
- Department of Chemistry, Faculty of Philosophy, Sciences and Letters of Ribeirão Preto, University of São Paulo, Avenida dos Bandeirantes, 3900, Ribeirão Preto, SP, 14040-901, Brazil
| | - Christian Pifl
- Department of Molecular Neurosciences, Centre for Brain Research, Medical University of Vienna, Spitalgasse 4, 1090, Vienna, Austria
| | - Gert Lubec
- Department of Neuroproteomics, Paracelsus Medical University, 5020, Salzburg, Austria.
| | - Eduardo R Perez Gonzalez
- Laboratory of Fine Organic Chemistry, Department of Chemistry and Biochemistry, Faculty of Sciences and Technology of São Paulo State University, Presidente Prudente, São Paulo, 19060-900, Brazil.
| |
Collapse
|
9
|
Bhat S, Niello M, Schicker K, Pifl C, Sitte HH, Freissmuth M, Sandtner W. Handling of intracellular K + determines voltage dependence of plasmalemmal monoamine transporter function. eLife 2021; 10:67996. [PMID: 34061030 PMCID: PMC8192120 DOI: 10.7554/elife.67996] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 05/30/2021] [Indexed: 12/16/2022] Open
Abstract
The concentrative power of the transporters for dopamine (DAT), norepinephrine (NET), and serotonin (SERT) is thought to be fueled by the transmembrane Na+ gradient, but it is conceivable that they can also tap other energy sources, for example, membrane voltage and/or the transmembrane K+ gradient. We have addressed this by recording uptake of endogenous substrates or the fluorescent substrate APP+(4-(4-dimethylamino)phenyl-1-methylpyridinium) under voltage control in cells expressing DAT, NET, or SERT. We have shown that DAT and NET differ from SERT in intracellular handling of K+. In DAT and NET, substrate uptake was voltage-dependent due to the transient nature of intracellular K+ binding, which precluded K+ antiport. SERT, however, antiports K+ and achieves voltage-independent transport. Thus, there is a trade-off between maintaining constant uptake and harvesting membrane potential for concentrative power, which we conclude to occur due to subtle differences in the kinetics of co-substrate ion binding in closely related transporters.
Collapse
Affiliation(s)
- Shreyas Bhat
- Institute of Pharmacology and the Gaston H. Glock Research Laboratories for Exploratory Drug Development, Center of Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Marco Niello
- Institute of Pharmacology and the Gaston H. Glock Research Laboratories for Exploratory Drug Development, Center of Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Klaus Schicker
- Division of Neurophysiology and Neuropharmacology, Centre for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Christian Pifl
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Harald H Sitte
- Institute of Pharmacology and the Gaston H. Glock Research Laboratories for Exploratory Drug Development, Center of Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Michael Freissmuth
- Institute of Pharmacology and the Gaston H. Glock Research Laboratories for Exploratory Drug Development, Center of Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Walter Sandtner
- Institute of Pharmacology and the Gaston H. Glock Research Laboratories for Exploratory Drug Development, Center of Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| |
Collapse
|
10
|
Rotolo RA, Kalaba P, Dragacevic V, Presby RE, Neri J, Robertson E, Yang JH, Correa M, Bakulev V, Volkova NN, Pifl C, Lubec G, Salamone JD. Behavioral and dopamine transporter binding properties of the modafinil analog (S, S)-CE-158: reversal of the motivational effects of tetrabenazine and enhancement of progressive ratio responding. Psychopharmacology (Berl) 2020; 237:3459-3470. [PMID: 32770257 PMCID: PMC7572767 DOI: 10.1007/s00213-020-05625-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 07/27/2020] [Indexed: 12/12/2022]
Abstract
RATIONALE Atypical dopamine (DA) transport blockers such as modafinil and its analogs may be useful for treating motivational symptoms of depression and other disorders. Previous research has shown that the DA depleting agent tetrabenazine can reliably induce motivational deficits in rats, as evidenced by a shift towards a low-effort bias in effort-based choice tasks. This is consistent with human studies showing that people with major depression show a bias towards low-effort activities. OBJECTIVES Recent studies demonstrated that the atypical DA transport (DAT) inhibitor (S)-CE-123 reversed tetrabenazine-induced motivational deficits, increased progressive ratio (PROG) lever pressing, and increased extracellular DA in the nucleus accumbens. In the present studies, a recently synthesized modafinil analog, (S, S)-CE-158, was assessed in a series of neurochemical and behavioral studies in rats. RESULTS (S, S)-CE-158 demonstrated the ability to reverse the effort-related effects of tetrabenazine and increase selection of high-effort PROG lever pressing in rats tested on PROG/chow feeding choice task. (S, S)-CE-158 showed a high selectivity for inhibiting DAT compared with other monoamine transporters, and systemic administration of (S, S)-CE-158 increased extracellular DA in the nucleus accumbens during the behaviorally active time course, which is consistent with the effects of (S)-CE-123 and other DAT inhibitors that enhance high-effort responding. CONCLUSIONS These studies provide an initial neurochemical characterization of a novel atypical DAT inhibitor, and demonstrate that this compound is active in models of effort-related choice. This research could contribute to the development of novel compounds for the treatment of motivational dysfunctions in humans.
Collapse
Affiliation(s)
- Renee A. Rotolo
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, USA
| | - Predrag Kalaba
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, Althanstraße 14, 1090 Vienna, Austria,Department of Neuroproteomics, Paracelsus Medical University, Salzburg, Austria
| | - Vladimir Dragacevic
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, Althanstraße 14, 1090 Vienna, Austria
| | - Rose E. Presby
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, USA
| | - Julia Neri
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, USA
| | - Emily Robertson
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, USA
| | - Jen-Hau Yang
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, USA
| | - Merce Correa
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, USA,Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, 12071 Castelló, Spain
| | - Vasiliy Bakulev
- Ural Federal University named after the first President of Russia B. N. Yeltsin, 19 Mira St., Yekaterinburg 620002, Russia
| | - Natalia N. Volkova
- Ural Federal University named after the first President of Russia B. N. Yeltsin, 19 Mira St., Yekaterinburg 620002, Russia
| | - Christian Pifl
- Centre for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Gert Lubec
- Department of Neuroproteomics, Paracelsus Medical University, Salzburg, Austria.
| | - John D. Salamone
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, USA,Corresponding authors: John D. Salamone () and Gert Lubec ()
| |
Collapse
|
11
|
Dorninger F, König T, Scholze P, Berger ML, Zeitler G, Wiesinger C, Gundacker A, Pollak DD, Huck S, Just WW, Forss-Petter S, Pifl C, Berger J. Disturbed neurotransmitter homeostasis in ether lipid deficiency. Hum Mol Genet 2020; 28:2046-2061. [PMID: 30759250 PMCID: PMC6548223 DOI: 10.1093/hmg/ddz040] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 01/21/2019] [Accepted: 02/10/2019] [Indexed: 12/30/2022] Open
Abstract
Plasmalogens, the most prominent ether (phospho)lipids in mammals, are structural components of most cellular membranes. Due to their physicochemical properties and abundance in the central nervous system, a role of plasmalogens in neurotransmission has been proposed, but conclusive data are lacking. Here, we targeted this issue in the glyceronephosphate O-acyltransferase (Gnpat) KO mouse, a model of complete deficiency in ether lipid biosynthesis. Throughout the study, focusing on adult male animals, we found reduced brain levels of various neurotransmitters. In the dopaminergic nigrostriatal tract, synaptic endings but not neuronal cell bodies were affected. Neurotransmitter turnover was altered in ether lipid-deficient murine as well as human post-mortem brain tissue. A generalized loss of synapses did not account for the neurotransmitter deficits, since the levels of several presynaptic proteins appeared unchanged. However, reduced amounts of vesicular monoamine transporter indicate a compromised vesicular uptake of neurotransmitters. As exemplified by norepinephrine, the release of neurotransmitters from Gnpat KO brain slices was diminished in response to strong electrical and chemical stimuli. Finally, addressing potential phenotypic correlates of the disturbed neurotransmitter homeostasis, we show that ether lipid deficiency manifests as hyperactivity and impaired social interaction. We propose that the lack of ether lipids alters the properties of synaptic vesicles leading to reduced amounts and release of neurotransmitters. These features likely contribute to the behavioral phenotype of Gnpat KO mice, potentially modeling some human neurodevelopmental disorders like autism or attention deficit hyperactivity disorder.
Collapse
Affiliation(s)
- Fabian Dorninger
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, Vienna, Austria
| | - Theresa König
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, Vienna, Austria
| | - Petra Scholze
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, Vienna, Austria
| | - Michael L Berger
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, Vienna, Austria
| | - Gerhard Zeitler
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, Vienna, Austria
| | - Christoph Wiesinger
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, Vienna, Austria
| | - Anna Gundacker
- Department of Neurophysiology and Neuropharmacology, Center for Physiology and Pharmacology, Medical University of Vienna, Schwarzspanierstraße 17, Vienna, Austria
| | - Daniela D Pollak
- Department of Neurophysiology and Neuropharmacology, Center for Physiology and Pharmacology, Medical University of Vienna, Schwarzspanierstraße 17, Vienna, Austria
| | - Sigismund Huck
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, Vienna, Austria
| | - Wilhelm W Just
- Biochemistry Center Heidelberg (BZH), University of Heidelberg, Im Neuenheimer Feld 328, Heidelberg, Germany
| | - Sonja Forss-Petter
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, Vienna, Austria
| | - Christian Pifl
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, Vienna, Austria
| | - Johannes Berger
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, Vienna, Austria
| |
Collapse
|
12
|
Korchynska S, Krassnitzer M, Malenczyk K, Prasad RB, Tretiakov EO, Rehman S, Cinquina V, Gernedl V, Farlik M, Petersen J, Hannes S, Schachenhofer J, Reisinger SN, Zambon A, Asplund O, Artner I, Keimpema E, Lubec G, Mulder J, Bock C, Pollak DD, Romanov RA, Pifl C, Groop L, Hökfelt TGM, Harkany T. Life-long impairment of glucose homeostasis upon prenatal exposure to psychostimulants. EMBO J 2020; 39:e100882. [PMID: 31750562 PMCID: PMC6939201 DOI: 10.15252/embj.2018100882] [Citation(s) in RCA: 9] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 10/10/2019] [Accepted: 10/21/2019] [Indexed: 12/21/2022] Open
Abstract
Maternal drug abuse during pregnancy is a rapidly escalating societal problem. Psychostimulants, including amphetamine, cocaine, and methamphetamine, are amongst the illicit drugs most commonly consumed by pregnant women. Neuropharmacology concepts posit that psychostimulants affect monoamine signaling in the nervous system by their affinities to neurotransmitter reuptake and vesicular transporters to heighten neurotransmitter availability extracellularly. Exacerbated dopamine signaling is particularly considered as a key determinant of psychostimulant action. Much less is known about possible adverse effects of these drugs on peripheral organs, and if in utero exposure induces lifelong pathologies. Here, we addressed this question by combining human RNA-seq data with cellular and mouse models of neuroendocrine development. We show that episodic maternal exposure to psychostimulants during pregnancy coincident with the intrauterine specification of pancreatic β cells permanently impairs their ability of insulin production, leading to glucose intolerance in adult female but not male offspring. We link psychostimulant action specifically to serotonin signaling and implicate the sex-specific epigenetic reprogramming of serotonin-related gene regulatory networks upstream from the transcription factor Pet1/Fev as determinants of reduced insulin production.
Collapse
Affiliation(s)
- Solomiia Korchynska
- Department of Molecular NeurosciencesCenter for Brain ResearchMedical University of ViennaViennaAustria
| | - Maria Krassnitzer
- Department of Molecular NeurosciencesCenter for Brain ResearchMedical University of ViennaViennaAustria
| | - Katarzyna Malenczyk
- Department of Molecular NeurosciencesCenter for Brain ResearchMedical University of ViennaViennaAustria
| | - Rashmi B Prasad
- Department of Clinical Sciences, Diabetes and Endocrinology CRCSkåne University Hospital MalmöMalmöSweden
| | - Evgenii O Tretiakov
- Department of Molecular NeurosciencesCenter for Brain ResearchMedical University of ViennaViennaAustria
| | - Sabah Rehman
- Department of Molecular NeurosciencesCenter for Brain ResearchMedical University of ViennaViennaAustria
| | - Valentina Cinquina
- Department of Molecular NeurosciencesCenter for Brain ResearchMedical University of ViennaViennaAustria
| | - Victoria Gernedl
- CeMM Research Center for Molecular Medicine of the Austrian Academy of SciencesViennaAustria
| | - Matthias Farlik
- CeMM Research Center for Molecular Medicine of the Austrian Academy of SciencesViennaAustria
| | - Julian Petersen
- Department of Molecular NeurosciencesCenter for Brain ResearchMedical University of ViennaViennaAustria
| | - Sophia Hannes
- Department of Molecular NeurosciencesCenter for Brain ResearchMedical University of ViennaViennaAustria
| | - Julia Schachenhofer
- Department of Molecular NeurosciencesCenter for Brain ResearchMedical University of ViennaViennaAustria
| | - Sonali N Reisinger
- Department of Neurophysiology and NeuropharmacologyCenter for Physiology and PharmacologyMedical University of ViennaViennaAustria
| | - Alice Zambon
- Department of Neurophysiology and NeuropharmacologyCenter for Physiology and PharmacologyMedical University of ViennaViennaAustria
| | - Olof Asplund
- Department of Clinical Sciences, Diabetes and Endocrinology CRCSkåne University Hospital MalmöMalmöSweden
| | - Isabella Artner
- Stem Cell CenterLund UniversityLundSweden
- Endocrine Cell Differentiation and FunctionLund University Diabetes CenterLund UniversityMalmöSweden
| | - Erik Keimpema
- Department of Molecular NeurosciencesCenter for Brain ResearchMedical University of ViennaViennaAustria
| | - Gert Lubec
- Paracelsus Medical UniversitySalzburgAustria
| | - Jan Mulder
- Science for Life LaboratoryKarolinska InstitutetSolnaSweden
| | - Christoph Bock
- CeMM Research Center for Molecular Medicine of the Austrian Academy of SciencesViennaAustria
| | - Daniela D Pollak
- Department of Neurophysiology and NeuropharmacologyCenter for Physiology and PharmacologyMedical University of ViennaViennaAustria
| | - Roman A Romanov
- Department of Molecular NeurosciencesCenter for Brain ResearchMedical University of ViennaViennaAustria
| | - Christian Pifl
- Department of Molecular NeurosciencesCenter for Brain ResearchMedical University of ViennaViennaAustria
| | - Leif Groop
- Department of Clinical Sciences, Diabetes and Endocrinology CRCSkåne University Hospital MalmöMalmöSweden
- Institute for Molecular Medicine Finland (FIMM)Helsinki UniversityHelsinkiFinland
| | | | - Tibor Harkany
- Department of Molecular NeurosciencesCenter for Brain ResearchMedical University of ViennaViennaAustria
- Department of NeuroscienceKarolinska InstitutetSolnaSweden
| |
Collapse
|
13
|
Kalaba P, Ilić M, Aher NY, Dragačević V, Wieder M, Zehl M, Wackerlig J, Beyl S, Sartori SB, Ebner K, Roller A, Lukic N, Beryozkina T, Gonzalez ERP, Neill P, Khan JA, Bakulev V, Leban JJ, Hering S, Pifl C, Singewald N, Lubec J, Urban E, Sitte HH, Langer T, Lubec G. Structure-Activity Relationships of Novel Thiazole-Based Modafinil Analogues Acting at Monoamine Transporters. J Med Chem 2019; 63:391-417. [PMID: 31841637 DOI: 10.1021/acs.jmedchem.9b01938] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Atypical dopamine reuptake inhibitors, such as modafinil, are used for the treatment of sleeping disorders and investigated as potential therapeutics against cocaine addiction and for cognitive enhancement. Our continuous effort to find modafinil analogues with higher inhibitory activity on and selectivity toward the dopamine transporter (DAT) has previously led to the promising thiazole-containing derivatives CE-103, CE-111, CE-123, and CE-125. Here, we describe the synthesis and activity of a series of compounds based on these scaffolds, which resulted in several new selective DAT inhibitors and gave valuable insights into the structure-activity relationships. Introduction of the second chiral center and subsequent chiral separations provided all four stereoisomers, whereby the S-configuration on both generally exerted the highest activity and selectivity on DAT. The representative compound of this series was further characterized by in silico, in vitro, and in vivo studies that have demonstrated both safety and efficacy profile of this compound class.
Collapse
Affiliation(s)
- Predrag Kalaba
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences , University of Vienna , Althanstraße 14 , 1090 Vienna , Austria
| | - Marija Ilić
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences , University of Vienna , Althanstraße 14 , 1090 Vienna , Austria
| | - Nilima Y Aher
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences , University of Vienna , Althanstraße 14 , 1090 Vienna , Austria
| | - Vladimir Dragačević
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences , University of Vienna , Althanstraße 14 , 1090 Vienna , Austria
| | - Marcus Wieder
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences , University of Vienna , Althanstraße 14 , 1090 Vienna , Austria
| | - Martin Zehl
- Department of Analytical Chemistry, Faculty of Chemistry , University of Vienna , Währinger Straße 38 , 1090 Vienna , Austria
| | - Judith Wackerlig
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences , University of Vienna , Althanstraße 14 , 1090 Vienna , Austria
| | - Stanislav Beyl
- Department of Pharmacology and Toxicology, Faculty of Life Sciences , University of Vienna , Althanstraße 14 , 1090 Vienna , Austria
| | - Simone B Sartori
- Center for Molecular Biosciences Innsbruck (CMBI), Department of Pharmacology and Toxicology, Institute of Pharmacy , Leopold Franzens University Innsbruck , 6020 Innsbruck , Austria
| | - Karl Ebner
- Center for Molecular Biosciences Innsbruck (CMBI), Department of Pharmacology and Toxicology, Institute of Pharmacy , Leopold Franzens University Innsbruck , 6020 Innsbruck , Austria
| | - Alexander Roller
- X-ray Structure Analysis Centre, Faculty of Chemistry , University of Vienna , Währinger Straße 38 , 1090 Vienna , Austria
| | - Natalie Lukic
- X-ray Structure Analysis Centre, Faculty of Chemistry , University of Vienna , Währinger Straße 38 , 1090 Vienna , Austria
| | - Tetyana Beryozkina
- Ural Federal University Named after the First President of Russia B. N. Yeltsin , 19 Mira st. , Yekaterinburg 620002 , Russia
| | - Eduardo Rene Perez Gonzalez
- Laboratory of Fine Organic Chemistry, Department of Chemistry and Biochemistry, Faculty of Science and Technology , University of Sao Paulo State , Roberto Simonsen 305 , CEP 19060-900 , Presidente Prudente , SP , Brazil
| | - Philip Neill
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences , University of Vienna , Althanstraße 14 , 1090 Vienna , Austria
| | - Jawad Akbar Khan
- Institute of Pharmacology, Centre of Physiology and Pharmacology , Medical University of Vienna , 1090 Vienna , Austria
| | - Vasiliy Bakulev
- Ural Federal University Named after the First President of Russia B. N. Yeltsin , 19 Mira st. , Yekaterinburg 620002 , Russia
| | - Johann Jakob Leban
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences , University of Vienna , Althanstraße 14 , 1090 Vienna , Austria
| | - Steffen Hering
- Department of Pharmacology and Toxicology, Faculty of Life Sciences , University of Vienna , Althanstraße 14 , 1090 Vienna , Austria
| | - Christian Pifl
- Centre for Brain Research , Medical University of Vienna , 1090 Vienna , Austria
| | - Nicolas Singewald
- Center for Molecular Biosciences Innsbruck (CMBI), Department of Pharmacology and Toxicology, Institute of Pharmacy , Leopold Franzens University Innsbruck , 6020 Innsbruck , Austria
| | - Jana Lubec
- Neuroscience Laboratory , Paracelsus Medical University , A-5020 Salzburg , Austria
| | - Ernst Urban
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences , University of Vienna , Althanstraße 14 , 1090 Vienna , Austria
| | - Harald H Sitte
- Institute of Pharmacology, Centre of Physiology and Pharmacology , Medical University of Vienna , 1090 Vienna , Austria
| | - Thierry Langer
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences , University of Vienna , Althanstraße 14 , 1090 Vienna , Austria
| | - Gert Lubec
- Neuroscience Laboratory , Paracelsus Medical University , A-5020 Salzburg , Austria
| |
Collapse
|
14
|
Hörtnagl H, Pifl C, Hörtnagl E, Reiner A, Sperk G. Distinct gradients of various neurotransmitter markers in caudate nucleus and putamen of the human brain. J Neurochem 2019; 152:650-662. [PMID: 31608979 PMCID: PMC7078952 DOI: 10.1111/jnc.14897] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 10/07/2019] [Accepted: 10/10/2019] [Indexed: 01/23/2023]
Abstract
The caudate nucleus (CN) and the putamen (PUT) as parts of the human striatum are distinguished by a marked heterogeneity in functional, anatomical, and neurochemical patterns. Our study aimed to document in detail the regional diversity in the distribution of dopamine (DA), serotonin, γ‐aminobuturic acid, and choline acetyltransferase within the CN and PUT. For this purpose we dissected the CN as well as the PUT of 12 post‐mortem brains of human subjects with no evidence of neurological and psychiatric disorders (38–81 years old) into about 80 tissue parts. We then investigated rostro‐caudal, dorso‐ventral, and medio‐lateral gradients of these neurotransmitter markers. All parameters revealed higher levels, turnover rates, or activities in the PUT than in the CN. Within the PUT, DA levels increased continuously from rostral to caudal. In contrast, the lowest molar ratio of homovanillic acid to DA, a marker of DA turnover, coincided with highest DA levels in the caudal PUT, the part of the striatum with the highest loss of DA in Parkinson’s disease (N. Engl. J. Med., 318, 1988, 876). Highest DA concentrations were found in the most central areas both in the PUT and CN. We observed an age‐dependent loss of DA in the PUT and CN that did not correspond to the loss described for Parkinson’s disease indicating different mechanisms inducing the deficit of DA. Our data demonstrate a marked heterogeneity in the anatomical distribution of neurotransmitter markers in the human dorsal striatum indicating anatomical and functional diversity within this brain structure. ![]()
Collapse
Affiliation(s)
- Heide Hörtnagl
- Department of Pharmacology, Innsbruck Medical University, Innsbruck, Austria
| | - Christian Pifl
- Centre for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Erik Hörtnagl
- ipsum, interkultureller Kunstverein, Müllerstr. 28, Innsbruck, Austria
| | | | - Günther Sperk
- Department of Pharmacology, Innsbruck Medical University, Innsbruck, Austria
| |
Collapse
|
15
|
Pifl C. The time delay between in vivo imaging and postmortem data poses a caveat on "no link" findings. Mov Disord 2019; 34:1579-1580. [PMID: 31769093 PMCID: PMC6856799 DOI: 10.1002/mds.27847] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 07/15/2019] [Indexed: 11/11/2022] Open
Affiliation(s)
- Christian Pifl
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
| |
Collapse
|
16
|
Alpár A, Zahola P, Hanics J, Hevesi Z, Korchynska S, Benevento M, Pifl C, Zachar G, Perugini J, Severi I, Leitgeb P, Bakker J, Miklosi AG, Tretiakov E, Keimpema E, Arque G, Tasan RO, Sperk G, Malenczyk K, Máté Z, Erdélyi F, Szabó G, Lubec G, Palkovits M, Giordano A, Hökfelt TG, Romanov RA, Horvath TL, Harkany T. Hypothalamic CNTF volume transmission shapes cortical noradrenergic excitability upon acute stress. EMBO J 2018; 37:e100087. [PMID: 30209240 PMCID: PMC6213283 DOI: 10.15252/embj.2018100087] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [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: 06/21/2018] [Revised: 08/10/2018] [Accepted: 08/13/2018] [Indexed: 02/06/2023] Open
Abstract
Stress-induced cortical alertness is maintained by a heightened excitability of noradrenergic neurons innervating, notably, the prefrontal cortex. However, neither the signaling axis linking hypothalamic activation to delayed and lasting noradrenergic excitability nor the molecular cascade gating noradrenaline synthesis is defined. Here, we show that hypothalamic corticotropin-releasing hormone-releasing neurons innervate ependymal cells of the 3rd ventricle to induce ciliary neurotrophic factor (CNTF) release for transport through the brain's aqueductal system. CNTF binding to its cognate receptors on norepinephrinergic neurons in the locus coeruleus then initiates sequential phosphorylation of extracellular signal-regulated kinase 1 and tyrosine hydroxylase with the Ca2+-sensor secretagogin ensuring activity dependence in both rodent and human brains. Both CNTF and secretagogin ablation occlude stress-induced cortical norepinephrine synthesis, ensuing neuronal excitation and behavioral stereotypes. Cumulatively, we identify a multimodal pathway that is rate-limited by CNTF volume transmission and poised to directly convert hypothalamic activation into long-lasting cortical excitability following acute stress.
Collapse
Affiliation(s)
- Alán Alpár
- SE NAP Research Group of Experimental Neuroanatomy and Developmental Biology, Semmelweis University, Budapest, Hungary
- Department of Anatomy, Histology, and Embryology, Semmelweis University, Budapest, Hungary
| | - Péter Zahola
- SE NAP Research Group of Experimental Neuroanatomy and Developmental Biology, Semmelweis University, Budapest, Hungary
- Department of Anatomy, Histology, and Embryology, Semmelweis University, Budapest, Hungary
| | - János Hanics
- SE NAP Research Group of Experimental Neuroanatomy and Developmental Biology, Semmelweis University, Budapest, Hungary
- Department of Anatomy, Histology, and Embryology, Semmelweis University, Budapest, Hungary
| | - Zsófia Hevesi
- SE NAP Research Group of Experimental Neuroanatomy and Developmental Biology, Semmelweis University, Budapest, Hungary
| | - Solomiia Korchynska
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Marco Benevento
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Christian Pifl
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Gergely Zachar
- Department of Anatomy, Histology, and Embryology, Semmelweis University, Budapest, Hungary
| | - Jessica Perugini
- Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Marche Polytechnic University, Ancona, Italy
| | - Ilenia Severi
- Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Marche Polytechnic University, Ancona, Italy
| | - Patrick Leitgeb
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Joanne Bakker
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Andras G Miklosi
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | | | - Erik Keimpema
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Gloria Arque
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Ramon O Tasan
- Department of Pharmacology, Medical University Innsbruck, Innsbruck, Austria
| | - Günther Sperk
- Department of Pharmacology, Medical University Innsbruck, Innsbruck, Austria
| | - Katarzyna Malenczyk
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Zoltán Máté
- Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Ferenc Erdélyi
- Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Gábor Szabó
- Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Gert Lubec
- Paracelsus Medical University, Salzburg, Austria
| | - Miklós Palkovits
- Department of Anatomy, Histology, and Embryology, Semmelweis University, Budapest, Hungary
- Human Brain Tissue Bank and Laboratory, Semmelweis University, Budapest, Hungary
| | - Antonio Giordano
- Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Marche Polytechnic University, Ancona, Italy
| | - Tomas Gm Hökfelt
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Roman A Romanov
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
- Immanuel Kant Baltic Federal University, Kaliningrad, Russia
| | - Tamas L Horvath
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Departments of Comparative Medicine and Neuroscience, Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, CT, USA
- Department of Anatomy and Histology, University of Veterinary Medicine, Budapest, Hungary
| | - Tibor Harkany
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
- Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Marche Polytechnic University, Ancona, Italy
| |
Collapse
|
17
|
Maier J, Mayer FP, Luethi D, Holy M, Jäntsch K, Reither H, Hirtler L, Hoener MC, Liechti ME, Pifl C, Brandt SD, Sitte HH. The psychostimulant (±)-cis-4,4'-dimethylaminorex (4,4'-DMAR) interacts with human plasmalemmal and vesicular monoamine transporters. Neuropharmacology 2018; 138:282-291. [PMID: 29908239 DOI: 10.1016/j.neuropharm.2018.06.018] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 05/01/2018] [Accepted: 06/12/2018] [Indexed: 10/28/2022]
Abstract
(±)-cis-4,4'-Dimethylaminorex (4,4'-DMAR) is a new psychoactive substance (NPS) that has been associated with 31 fatalities and other adverse events in Europe between June 2013 and February 2014. We used in vitro uptake inhibition and transporter release assays to determine the effects of 4,4'-DMAR on human high-affinity transporters for dopamine (DAT), norepinephrine (NET) and serotonin (SERT). In addition, we assessed its binding affinities to monoamine receptors and transporters. Furthermore, we investigated the interaction of 4,4'-DMAR with the vesicular monoamine transporter 2 (VMAT2) in rat phaeochromocytoma (PC12) cells and synaptic vesicles prepared from human striatum. 4,4'-DMAR inhibited uptake mediated by human DAT, NET or SERT, respectively in the low micromolar range (IC50 values < 2 μM). Release assays identified 4,4'-DMAR as a substrate type releaser, capable of inducing transporter-mediated reverse transport via DAT, NET and SERT. Furthermore, 4,4'-DMAR inhibited both the rat and human isoforms of VMAT2 at a potency similar to 3,4-methylenedioxymethylamphetamine (MDMA). This study identified 4,4'-DMAR as a potent non-selective monoamine releasing agent. In contrast to the known effects of aminorex and 4-methylaminorex, 4,4'-DMAR exerts profound effects on human SERT. The latter finding is consistent with the idea that fatalities associated with its abuse may be linked to monoaminergic toxicity including serotonin syndrome. The activity at VMAT2 suggests that chronic abuse of 4,4'-DMAR may result in long-term neurotoxicity.
Collapse
Affiliation(s)
- Julian Maier
- Medical University of Vienna, Center for Physiology and Pharmacology, Institute of Pharmacology, Währingerstraße 13A, 1090, Vienna, Austria
| | - Felix P Mayer
- Medical University of Vienna, Center for Physiology and Pharmacology, Institute of Pharmacology, Währingerstraße 13A, 1090, Vienna, Austria
| | - Dino Luethi
- University Hospital Basel and University of Basel, Division of Clinical Pharmacology and Toxicology, Department of Biomedicine, Hebelstraße 20, 4031, Basel, Switzerland
| | - Marion Holy
- Medical University of Vienna, Center for Physiology and Pharmacology, Institute of Pharmacology, Währingerstraße 13A, 1090, Vienna, Austria
| | - Kathrin Jäntsch
- Medical University of Vienna, Center for Physiology and Pharmacology, Institute of Pharmacology, Währingerstraße 13A, 1090, Vienna, Austria
| | - Harald Reither
- Medical University of Vienna, Center for Brain Research, Department of Molecular Neurosciences, Spitalgasse 4, 1090, Vienna, Austria
| | - Lena Hirtler
- Medical University of Vienna, Center for Anatomy and Cell Biology, Währingerstraße 13, 1090, Vienna, Austria
| | - Marius C Hoener
- F. Hoffmann - La Roche Ltd., pRED, Roche Innovation Center Basel, Neuroscience Research, Department of Neurosymptomatic Domains, Grenzacherstraße 124, 4070, Basel, Switzerland
| | - Matthias E Liechti
- University Hospital Basel and University of Basel, Division of Clinical Pharmacology and Toxicology, Department of Biomedicine, Hebelstraße 20, 4031, Basel, Switzerland
| | - Christian Pifl
- Medical University of Vienna, Center for Brain Research, Department of Molecular Neurosciences, Spitalgasse 4, 1090, Vienna, Austria
| | - Simon D Brandt
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Byrom Street, Liverpool, L3 3AF, UK
| | - Harald H Sitte
- Medical University of Vienna, Center for Physiology and Pharmacology, Institute of Pharmacology, Währingerstraße 13A, 1090, Vienna, Austria; Center for Addiction Research and Science, Medical University Vienna, Waehringerstrasse 13A, 1090 Vienna, Austria.
| |
Collapse
|
18
|
Pifl C, Reither H, Del Rey NLG, Cavada C, Obeso JA, Blesa J. Early Paradoxical Increase of Dopamine: A Neurochemical Study of Olfactory Bulb in Asymptomatic and Symptomatic MPTP Treated Monkeys. Front Neuroanat 2017; 11:46. [PMID: 28611598 PMCID: PMC5447291 DOI: 10.3389/fnana.2017.00046] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2017] [Accepted: 05/12/2017] [Indexed: 11/13/2022] Open
Abstract
Parkinson's disease (PD) is a neurodegenerative disease with both motor and non-motor manifestations. Hyposmia is one of the early non-motor symptoms, which can precede motor symptoms by several years. The relationship between hyposmia and PD remains elusive. Olfactory bulb (OB) pathology shows an increased number of olfactory dopaminergic cells, protein aggregates and dysfunction of neurotransmitter systems. In this study we examined tissue levels of dopamine (DA) and serotonin (5-hydroxytryptamine, 5-HT) and their metabolites, of noradrenaline (NA) and of the amino acid neurotransmitters aspartate, glutamate, taurine and γ-aminobutyric acid in OBs of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) treated Macaca fascicularis in different stages, including monkeys who were always asymptomatic, monkeys who recovered from mild parkinsonian signs, and monkeys with stable moderate or severe parkinsonism. DA was increased compared to controls, while neither NA and 5-HT nor the amino acid neurotransmitters were significantly changed. Furthermore, DA increased before stable motor deficits appear with +51% in asymptomatic and +96% in recovered monkeys. Unchanged DA metabolites suggest a special metabolic profile of the newly formed DA neurons. Significant correlation of homovanillic acid (HVA) with taurine single values within the four MPTP groups and of aspartate with taurine within the asymptomatic and recovered MPTP groups, but not within the controls suggest interactions in the OB between taurine and the DA system and taurine and the excitatory neurotransmitter triggered by MPTP. This first investigation of OB in various stages after MPTP administration suggests that the DA increase seems to be an early phenomenon, not requiring profound nigrostriatal neurodegeneration or PD symptoms.
Collapse
Affiliation(s)
- Christian Pifl
- Center for Brain Research, Medical University of ViennaVienna, Austria
| | - Harald Reither
- Center for Brain Research, Medical University of ViennaVienna, Austria
| | - Natalia Lopez-Gonzalez Del Rey
- HM CINAC, Hospital Universitario HM Puerta del SurMostoles, Spain.,Centro de Investigacion Biomedica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Instituto Carlos III, Ministerio de Ciencia e InnovacionMadrid, Spain
| | - Carmen Cavada
- Departamento de Anatomia, Histologia y Neurociencia, Facultad de Medicina, Universidad Autonoma de MadridMadrid, Spain
| | - Jose A Obeso
- HM CINAC, Hospital Universitario HM Puerta del SurMostoles, Spain.,Centro de Investigacion Biomedica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Instituto Carlos III, Ministerio de Ciencia e InnovacionMadrid, Spain
| | - Javier Blesa
- HM CINAC, Hospital Universitario HM Puerta del SurMostoles, Spain.,Centro de Investigacion Biomedica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Instituto Carlos III, Ministerio de Ciencia e InnovacionMadrid, Spain
| |
Collapse
|
19
|
Sitte HH, Pifl C, Rajput AH, Hörtnagl H, Tong J, Lloyd GK, Kish SJ, Hornykiewicz O. Dopamine and noradrenaline, but not serotonin, in the human claustrum are greatly reduced in patients with Parkinson's disease: possible functional implications. Eur J Neurosci 2017; 45:1356. [PMID: 28523903 DOI: 10.1111/ejn.13573] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
20
|
Sitte HH, Pifl C, Rajput AH, Hörtnagl H, Tong J, Lloyd GK, Kish SJ, Hornykiewicz O. Dopamine and noradrenaline, but not serotonin, in the human claustrum are greatly reduced in patients with Parkinson's disease: possible functional implications. Eur J Neurosci 2016; 45:192-197. [PMID: 27741357 DOI: 10.1111/ejn.13435] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 09/30/2016] [Accepted: 10/10/2016] [Indexed: 11/28/2022]
Abstract
In the human brain, the claustrum is a small subcortical telencephalic nucleus, situated between the insular cortex and the putamen. A plethora of neuroanatomical studies have shown the existence of dense, widespread, bidirectional and bilateral monosynaptic interconnections between the claustrum and most cortical areas. A rapidly growing body of experimental evidence points to the integrative role of claustrum in complex brain functions, from motor to cognitive. Here, we examined for the first time, the behaviour of the classical monoamine neurotransmitters dopamine, noradrenaline and serotonin in the claustrum of the normal autopsied human brain and of patients who died with idiopathic Parkinson's disease (PD). We found in the normal claustrum substantial amounts of all three monoamine neurotransmitters, substantiating the existence of the respective brain stem afferents to the claustrum. In PD, the levels of dopamine and noradrenaline were greatly reduced by 93 and 81%, respectively. Serotonin levels remained unchanged. We propose that by virtue of their projections to the claustrum, the brain stem dopamine, noradrenaline and serotonin systems interact directly with the cortico-claustro-cortical information processing mechanisms, by-passing their (parallel) routes via the basal ganglia-thalamo-cortical circuits. We suggest that loss of dopamine and noradrenaline in the PD claustrum is critical in the aetiology of both the motor and the non-motor symptoms of PD.
Collapse
Affiliation(s)
- Harald H Sitte
- Centre for Physiology and Pharmacology, Institute of Pharmacology, Medical University of Vienna, Waehringerstrasse 13A, A-1090, Vienna, Austria
| | - Christian Pifl
- Centre for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Ali H Rajput
- Division of Neurology, Saskatchewan Movement Disorders Program, Saskatoon Health Region, University of Saskatchewan, Saskatoon, SK, Canada
| | - Heide Hörtnagl
- Department of Pharmacology, Innsbruck Medical University, Innsbruck, Austria
| | - Junchao Tong
- Human Brain Laboratory, Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | | | - Stephen J Kish
- Human Brain Laboratory, Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Oleh Hornykiewicz
- Centre for Brain Research, Medical University of Vienna, Vienna, Austria
| |
Collapse
|
21
|
Pifl C. Problems with traffic ahead: Synaptic vesicles in Parkinson's disease. Mov Disord 2016; 31:1480. [PMID: 27477200 DOI: 10.1002/mds.26735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 06/26/2016] [Indexed: 11/10/2022] Open
Affiliation(s)
- Christian Pifl
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| |
Collapse
|
22
|
Peneder TM, Bauer J, Pifl C. Apoptosis-inducing factor in nigral dopamine neurons: Higher levels in primates than in mice. Mov Disord 2016; 31:1729-1733. [PMID: 27297192 DOI: 10.1002/mds.26695] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Revised: 05/06/2016] [Accepted: 05/10/2016] [Indexed: 02/01/2023] Open
Abstract
INTRODUCTION The nigrostriatal dopaminergic pathway is more susceptible to neurodegeneration in primates than in mice, including the neurotoxic effect of MPTP. Apoptosis-inducing-factor was shown to be involved in the pathogenesis of dopaminergic degeneration. We therefore compared its occurrence in nigral dopamine neurons of mice, monkeys, and humans. METHODS Paraffin-embedded brain slices, including the SNpc of C57BL/6J mice, rhesus monkeys, and humans, were immunohistochemically labeled for tyrosine hydroxylase (an enzyme of dopamine synthesis), microtubule-associated protein 2 (a neuronal marker), and apoptosis-inducing factor and examined by confocal laser scan microscopy. RESULTS The amount of apoptosis-inducing factor in TH-containing SN neurons was 15 times higher in monkeys and 50 times higher in humans than in mice in terms of apoptosis-inducing factor immunoreactive neuronal area excluding the nucleus. CONCLUSION The difference of apoptosis-inducing factor levels between primates and mice might contribute to the higher sensitivity of primates to MPTP-induced neurodegeneration of their nigrostriatal dopamine system. © 2016 International Parkinson and Movement Disorder Society.
Collapse
Affiliation(s)
- Tamara M Peneder
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Jan Bauer
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Christian Pifl
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
| |
Collapse
|
23
|
Pifl C, Reither H, Hornykiewicz O. The profile of mephedrone on human monoamine transporters differs from 3,4-methylenedioxymethamphetamine primarily by lower potency at the vesicular monoamine transporter. Eur J Pharmacol 2015; 755:119-26. [PMID: 25771452 DOI: 10.1016/j.ejphar.2015.03.004] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 03/02/2015] [Accepted: 03/04/2015] [Indexed: 11/29/2022]
Abstract
Mephedrone (4-methylmethcathinone, MMC) and 3,4-methylenedioxymethamphetamine (MDMA) are constituents of popular party drugs with psychoactive effects. Structurally they are amphetamine-like substances with monoamine neurotransmitter enhancing actions. We therefore compared their effects on the human monoamine transporters using human cell lines stably expressing the human noradrenaline, dopamine and serotonin transporter (NET, DAT and SERT); preparations of synaptic vesicles from human striatum in uptake experiments; and a superfusion system where releasing effects can be reliably measured. MMC and MDMA were equally potent in inhibiting noradrenaline uptake at NET, with IC50 values of 1.9 and 2.1 µM, respectively. Compared to their NET inhibition potency, both drugs were weaker uptake inhibitors at DAT and SERT, with MMC being more potent than MDMA at DAT (IC50: 5.9 vs 12.6 µM) and less potent than MDMA at SERT (IC50: 19.3 vs 7.6 µM). MMC and MDMA both induced concentration-dependently [(3)H]1-methyl-4-phenylpyridinium-release from NET-, DAT or SERT-expressing cells which was clearly transporter-mediated release as demonstrated by the selective inhibitory effects of nmolar to low µmolar concentrations of desipramine, GBR 12909 and fluoxetine, respectively. MMC and MDMA differed most in their inhibition of [(3)H]dopamine uptake by synaptic vesicles from human striatum with MDMA being 10-fold more potent than MMC (IC50: 20 vs 223 µM) and their ability to release [(3)H]dopamine from human vesicular monoamine transporter expressing SH-SY5Y neuroblastoma cells in which MDMA seems to have a stronger effect. Our findings give a molecular explanation to the lower long-term neurotoxicity of MMC compared to MDMA.
Collapse
Affiliation(s)
- Christian Pifl
- Center for Brain Research, Medical University of Vienna, Spitalgasse 4, A-1090 Vienna, Austria.
| | - Harald Reither
- Center for Brain Research, Medical University of Vienna, Spitalgasse 4, A-1090 Vienna, Austria
| | - Oleh Hornykiewicz
- Center for Brain Research, Medical University of Vienna, Spitalgasse 4, A-1090 Vienna, Austria
| |
Collapse
|
24
|
Pifl C, Rajput A, Reither H, Blesa J, Cavada C, Obeso JA, Rajput AH, Hornykiewicz O. Is Parkinson's disease a vesicular dopamine storage disorder? Evidence from a study in isolated synaptic vesicles of human and nonhuman primate striatum. J Neurosci 2014; 34:8210-8. [PMID: 24920625 PMCID: PMC6608236 DOI: 10.1523/jneurosci.5456-13.2014] [Citation(s) in RCA: 118] [Impact Index Per Article: 11.8] [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: 12/30/2013] [Revised: 05/06/2014] [Accepted: 05/07/2014] [Indexed: 12/21/2022] Open
Abstract
The cause of degeneration of nigrostriatal dopamine (DA) neurons in idiopathic Parkinson's disease (PD) is still unknown. Intraneuronally, DA is largely confined to synaptic vesicles where it is protected from metabolic breakdown. In the cytoplasm, however, free DA can give rise to formation of cytotoxic free radicals. Normally, the concentration of cytoplasmic DA is kept at a minimum by continuous pumping activity of the vesicular monoamine transporter (VMAT)2. Defects in handling of cytosolic DA by VMAT2 increase levels of DA-generated oxy radicals ultimately resulting in degeneration of DAergic neurons. Here, we isolated for the first time, DA storage vesicles from the striatum of six autopsied brains of PD patients and four controls and measured several indices of vesicular DA storage mechanisms. We found that (1) vesicular uptake of DA and binding of the VMAT2-selective label [(3)H]dihydrotetrabenazine were profoundly reduced in PD by 87-90% and 71-80%, respectively; (2) after correcting for DA nerve terminal loss, DA uptake per VMAT2 transport site was significantly reduced in PD caudate and putamen by 53 and 55%, respectively; (3) the VMAT2 transport defect appeared specific for PD as it was not present in Macaca fascicularis (7 MPTP and 8 controls) with similar degree of MPTP-induced nigrostriatal neurodegeneration; and (4) DA efflux studies and measurements of acidification in the vesicular preparations suggest that the DA storage impairment was localized at the VMAT2 protein itself. We propose that this VMAT2 defect may be an early abnormality promoting mechanisms leading to nigrostriatal DA neuron death in PD.
Collapse
Affiliation(s)
- Christian Pifl
- Center for Brain Research, Medical University of Vienna, A-1090 Vienna, Austria,
| | - Alex Rajput
- Movement Disorders Program Saskatchewan, Royal University Hospital, University of Saskatchewan, Saskatoon, Saskatchewan, SK S7N OW8, Canada
| | - Harald Reither
- Center for Brain Research, Medical University of Vienna, A-1090 Vienna, Austria
| | - Javier Blesa
- Movement Disorders Group, Neurosciences Division, CIMA, and Department of Neurology and Neurosurgery, Clinica Universidad de Navarra, E31008 Pamplona, Spain, and
| | - Carmen Cavada
- Departamento de Anatomía, Histología y Neurociencia, Facultad de Medicina, Universidad Autónoma de Madrid, E28049 Madrid, Spain
| | - José A Obeso
- Movement Disorders Group, Neurosciences Division, CIMA, and Department of Neurology and Neurosurgery, Clinica Universidad de Navarra, E31008 Pamplona, Spain, and
| | - Ali H Rajput
- Movement Disorders Program Saskatchewan, Royal University Hospital, University of Saskatchewan, Saskatoon, Saskatchewan, SK S7N OW8, Canada
| | - Oleh Hornykiewicz
- Center for Brain Research, Medical University of Vienna, A-1090 Vienna, Austria
| |
Collapse
|
25
|
Pifl C, Hornykiewicz O, Blesa J, Adánez R, Cavada C, Obeso JA. Reduced noradrenaline, but not dopamine and serotonin in motor thalamus of the MPTP primate: relation to severity of Parkinsonism. J Neurochem 2013; 125:657-62. [DOI: 10.1111/jnc.12162] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Revised: 01/08/2013] [Accepted: 01/14/2013] [Indexed: 11/30/2022]
Affiliation(s)
- Christian Pifl
- Center for Brain Research; Medical University of Vienna; Vienna Austria
| | - Oleh Hornykiewicz
- Center for Brain Research; Medical University of Vienna; Vienna Austria
| | - Javier Blesa
- Movement Disorders Group; Neurosciences Division; CIMA, and Department of Neurology and Neurosurgery; Clínica Universidad de Navarra; Pamplona Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED); Instituto Carlos III, Ministerio de Ciencia e Innovación; Madrid Spain
| | - Rebeca Adánez
- Movement Disorders Group; Neurosciences Division; CIMA, and Department of Neurology and Neurosurgery; Clínica Universidad de Navarra; Pamplona Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED); Instituto Carlos III, Ministerio de Ciencia e Innovación; Madrid Spain
| | - Carmen Cavada
- Departamento de Anatomía, Histología y Neurociencia; Facultad de Medicina; Universidad Autónoma de Madrid; Madrid Spain
- Instituto de Investigación Sanitaria IdiPAZ; Madrid Spain
| | - José A. Obeso
- Movement Disorders Group; Neurosciences Division; CIMA, and Department of Neurology and Neurosurgery; Clínica Universidad de Navarra; Pamplona Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED); Instituto Carlos III, Ministerio de Ciencia e Innovación; Madrid Spain
| |
Collapse
|
26
|
Pifl C, Kish SJ, Hornykiewicz O. Thalamic noradrenaline in Parkinson's disease: deficits suggest role in motor and non-motor symptoms. Mov Disord 2012; 27:1618-24. [PMID: 23038412 DOI: 10.1002/mds.25109] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2012] [Revised: 06/04/2012] [Accepted: 06/11/2012] [Indexed: 01/18/2023] Open
Abstract
The thalamus occupies a pivotal position within the corticobasal ganglia-cortical circuits. In Parkinson's disease (PD), the thalamus exhibits pathological neuronal discharge patterns, foremost increased bursting and oscillatory activity, which are thought to perturb the faithful transfer of basal ganglia impulse flow to the cortex. Analogous abnormal thalamic discharge patterns develop in animals with experimentally reduced thalamic noradrenaline; conversely, added to thalamic neuronal preparations, noradrenaline exhibits marked antioscillatory and antibursting activity. Our study is based on this experimentally established link between noradrenaline and the quality of thalamic neuronal discharges. We analyzed 14 thalamic nuclei from all functionally relevant territories of 9 patients with PD and 8 controls, and measured noradrenaline with high-performance liquid chromatography with electrochemical detection. In PD, noradrenaline was profoundly reduced in all nuclei of the motor (pallidonigral and cerebellar) thalamus (ventroanterior: -86%, P = .0011; ventrolateral oral: -87%, P = .0010; ventrolateral caudal: -89%, P = .0014): Also, marked noradrenaline losses, ranging from 68% to 91% of controls, were found in other thalamic territories, including associative, limbic and intralaminar regions; the primary sensory regions were only mildly affected. The marked noradrenergic deafferentiation of the thalamus discloses a strategically located noradrenergic component in the overall pathophysiology of PD, suggesting a role in the complex mechanisms involved with the genesis of the motor and non-motor symptoms. Our study thus significantly contributes to the knowledge of the extrastriatal nondopaminergic mechanisms of PD with direct relevance to treatment of this disorder.
Collapse
Affiliation(s)
- Christian Pifl
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | | | | |
Collapse
|
27
|
Blesa J, Pifl C, Sánchez-González MA, Juri C, García-Cabezas MA, Adánez R, Iglesias E, Collantes M, Peñuelas I, Sánchez-Hernández JJ, Rodríguez-Oroz MC, Avendaño C, Hornykiewicz O, Cavada C, Obeso JA. The nigrostriatal system in the presymptomatic and symptomatic stages in the MPTP monkey model: a PET, histological and biochemical study. Neurobiol Dis 2012; 48:79-91. [PMID: 22677034 DOI: 10.1016/j.nbd.2012.05.018] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [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: 02/11/2012] [Revised: 05/20/2012] [Accepted: 05/24/2012] [Indexed: 11/19/2022] Open
Abstract
Parkinson's disease (PD) is diagnosed when striatal dopamine (DA) loss exceeds a certain threshold and the cardinal motor features become apparent. The presymptomatic compensatory mechanisms underlying the lack of motor manifestations despite progressive striatal depletion are not well understood. Most animal models of PD involve the induction of a severe dopaminergic deficit in an acute manner, which departs from the typical, chronic evolution of PD in humans. We have used 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) administered to monkeys via a slow intoxication protocol to produce a more gradual development of nigral lesion. Twelve control and 38 MPTP-intoxicated monkeys were divided into four groups. The latter included monkeys who were always asymptomatic, monkeys who recovered after showing mild parkinsonian signs, and monkeys with stable, moderate and severe parkinsonism. We found a close correlation between cell loss in the substantia nigra pars compacta (SNc) and striatal dopaminergic depletion and the four motor states. There was an overall negative correlation between the degree of parkinsonism (Kurlan scale) and in vivo PET ((18)F-DOPA K(i) and (11)C-DTBZ binding potential), as well as with TH-immunoreactive cell counts in SNc, striatal dopaminergic markers (TH, DAT and VMAT2) and striatal DA concentration. This intoxication protocol permits to establish a critical threshold of SNc cell loss and dopaminergic innervation distinguishing between the asymptomatic and symptomatic parkinsonian stages. Compensatory changes in nigrostriatal dopaminergic activity occurred in the recovered and parkinsonian monkeys when DA depletion was at least 88% of control, and accordingly may be considered too late to explain compensatory mechanisms in the early asymptomatic period. Our findings suggest the need for further exploration of the role of non-striatal mechanisms in PD prior to the development of motor features.
Collapse
Affiliation(s)
- J Blesa
- Movement Disorders Group, Neurosciences Division, CIMA, and Department of Neurology and Neurosurgery, Clínica Universidad de Navarra, Pamplona, Spain
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Sperk G, Wieselthaler-Hölzl A, Pirker S, Tasan R, Strasser SS, Drexel M, Pifl C, Marschalek J, Ortler M, Trinka E, Heitmair-Wietzorrek K, Ciofi P, Feucht M, Baumgartner C, Czech T. Glutamate decarboxylase 67 is expressed in hippocampal mossy fibers of temporal lobe epilepsy patients. Hippocampus 2011; 22:590-603. [PMID: 21509853 DOI: 10.1002/hipo.20923] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/05/2010] [Indexed: 11/12/2022]
Abstract
Recently, expression of glutamate decarboxylase-67 (GAD67), a key enzyme of GABA synthesis, was detected in the otherwise glutamatergic mossy fibers of the rat hippocampus. Synthesis of the enzyme was markedly enhanced after experimentally induced status epilepticus. Here, we investigated the expression of GAD67 protein and mRNA in 44 hippocampal specimens from patients with mesial temporal lobe epilepsy (TLE) using double immunofluorescence histochemistry, immunoblotting, and in situ hybridization. Both in specimens with (n = 37) and without (n = 7) hippocampal sclerosis, GAD67 was highly coexpressed with dynorphin in terminal areas of mossy fibers, including the dentate hilus and the stratum lucidum of sector CA3. In the cases with Ammon's horn sclerosis, also the inner molecular layer of the dentate gyrus contained strong staining for GAD67 immunoreactivity, indicating labeling of mossy fiber terminals that specifically sprout into this area. Double immunofluorescence revealed the colocalization of GAD67 immunoreactivity with the mossy fiber marker dynorphin. The extent of colabeling correlated with the number of seizures experienced by the patients. Furthermore, GAD67 mRNA was found in granule cells of the dentate gyrus. Levels, both of GAD67 mRNA and of GAD67 immunoreactivity were similar in sclerotic and nonsclerotic specimens and appeared to be increased compared to post mortem controls. Provided that the strong expression of GAD67 results in synthesis of GABA in hippocampal mossy fibers this may represent a self-protecting mechanism in TLE. In addition GAD67 expression also may result in conversion of excessive intracellular glutamate to nontoxic GABA within mossy fiber terminals.
Collapse
Affiliation(s)
- Günther Sperk
- Department of Pharmacology, Medical University Innsbruck, Austria.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Neuhaus W, Freidl M, Szkokan P, Berger M, Wirth M, Winkler J, Gabor F, Pifl C, Noe CR. Effects of NMDA receptor modulators on a blood-brain barrier in vitro model. Brain Res 2011; 1394:49-61. [PMID: 21549356 DOI: 10.1016/j.brainres.2011.04.003] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2010] [Revised: 03/21/2011] [Accepted: 04/01/2011] [Indexed: 01/29/2023]
Abstract
Changes of the functionality of the blood-brain barrier (BBB) have been reported in the context of several brain related diseases such as multiple sclerosis, epilepsy, Alzheimer's disease and stroke. Several publications indicated the presence and functionality of the NMDA receptor (NMDAR) at the brain endothelium and a possible involvement of the NMDAR in the above-mentioned diseases. Recently, it was shown that the application of the NMDAR antagonist MK801 can block several adverse effects at the BBB in vitro, but also that MK801 can significantly change the proteome of brain endothelial cells without simultaneous stimulation of NMDAR by glutamate. Based on these reports we investigated if NMDAR antagonists MK801 and D-APV can affect the intracellular calcium level (Ca²⁺i) of an in vitro BBB model based on human cell line ECV304 on their own and compared these results to effects mediated by NMDAR agonists glutamate and NMDA. Treatment of ECV304 cells for 30 min with glutamate resulted in no significant change of Ca²⁺i. On the contrary, application of NMDA and NMDAR antagonists D-APV and MK801 led to a significant and concentration dependent decrease of Ca²⁺i. Further studies revealed that glutamate was able to decrease the transendothelial electrical resistance (TEER) of the BBB in vitro model, whereas NMDA and D-APV were able to increase TEER. Analysis of the protein expression levels of tight junctional molecules ZO-1 and occludin showed a complex regulation after application of NMDAR modulators. In summary, it was shown that NMDAR antagonists can alter BBB key properties in vitro on their own. Moreover, although qPCR results confirmed the presence of NMDA receptor subunits NR1, NR2A, NR2B and NR2C, membrane binding studies failed to prove the typical plasma membrane localization and functionality in human BBB cell line ECV304.
Collapse
Affiliation(s)
- Winfried Neuhaus
- Department of Anaesthesia and Critical Care, University Hospital Würzburg, Oberdürrbacherstrasse 6, 97080 Würzburg, Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Peneder TM, Scholze P, Berger ML, Reither H, Heinze G, Bertl J, Bauer J, Richfield EK, Hornykiewicz O, Pifl C. Chronic exposure to manganese decreases striatal dopamine turnover in human alpha-synuclein transgenic mice. Neuroscience 2011; 180:280-92. [PMID: 21333719 DOI: 10.1016/j.neuroscience.2011.02.017] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2010] [Revised: 02/01/2011] [Accepted: 02/09/2011] [Indexed: 12/20/2022]
Abstract
Interaction of genetic and environmental factors is likely involved in Parkinson's disease (PD). Mutations and multiplications of alpha-synuclein (α-syn) cause familial PD, and chronic manganese (Mn) exposure can produce an encephalopathy with signs of parkinsonism. We exposed male transgenic C57BL/6J mice expressing human α-syn or the A53T/A30P doubly mutated human α-syn under the tyrosine hydroxylase promoter and non-transgenic littermates to MnCl₂-enriched (1%) or control food, starting at the age of 4 months. Locomotor activity was increased by Mn without significant effect of the transgenes. Mice were sacrificed at the age of 7 or 20 months. Striatal Mn was significantly increased about three-fold in those exposed to MnCl₂. The number of tyrosine hydroxylase positive substantia nigra compacta neurons was significantly reduced in 20 months old mice (-10%), but Mn or transgenes were ineffective (three-way ANOVA with the factors gene, Mn and age). In 7 months old mice, striatal homovanillic acid (HVA)/dopamine (DA) ratios and aspartate levels were significantly increased in control mice with human α-syn as compared to non-transgenic controls (+17 and +11%, respectively); after Mn exposure both parameters were significantly reduced (-16 and -13%, respectively) in human α-syn mice, but unchanged in non-transgenic animals and mice with mutated α-syn (two-way ANOVA with factors gene and Mn). None of the parameters were changed in the 20 months old mice. Single HVA/DA ratios and single aspartate levels significantly correlated across all treatment groups suggesting a causal relationship between the rate of striatal DA metabolism and aspartate release. In conclusion, under our experimental conditions, Mn and human α-syn, wild-type and doubly mutated, did not interact to induce PD-like neurodegenerative changes. However, Mn significantly and selectively interacted with human wild-type α-syn on indices of striatal DA neurotransmission, the neurotransmitter most relevant to PD.
Collapse
Affiliation(s)
- T M Peneder
- Center for Brain Research, Medical University of Vienna, Spitalgasse 4, A-1090 Vienna, Austria
| | | | | | | | | | | | | | | | | | | |
Collapse
|
31
|
Peneder TM, Berger M, Scholze P, Heinze G, Bertl J, Bauer J, Hornykiewicz O, Richfield EK, Pifl C. Interaction of manganese with striatal dopamine turnover in human alpha-synuclein transgenic mice. BMC Pharmacol 2010. [PMCID: PMC3016525 DOI: 10.1186/1471-2210-10-s1-a16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
|
32
|
Pifl C, Wolf A, Rebernik P, Reither H, Berger ML. Zinc regulates the dopamine transporter in a membrane potential and chloride dependent manner. Neuropharmacology 2008; 56:531-40. [PMID: 19000913 DOI: 10.1016/j.neuropharm.2008.10.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2008] [Revised: 10/13/2008] [Accepted: 10/14/2008] [Indexed: 11/28/2022]
Abstract
The dopamine transporter (DAT), a membrane protein specifically expressed by dopaminergic neurons and mediating the action of psychostimulants and dopaminergic neurotoxins, is regulated by Zn(2+) which directly interacts with the protein. Herein, we report a host-cell-specific direction of the Zn(2+) effect on wild type DAT. Whereas low mumolar Zn(2+) decreased dopamine uptake by DAT expressing HEK293 cells, it stimulated uptake by DAT expressing SK-N-MC cells. Inhibition or stimulation was lost in a DAT construct without the binding site for Zn(2+). Also reverse transport was differentially affected by Zn(2+), dependent on whether the DAT was expressed in HEK293 or SK-N-MC cells. Pre-treatment of DAT expressing cells with phorbol-12-myristate-13-acetate, an activator of protein kinase C, attenuated the inhibitory effect of Zn(2+) on uptake in HEK293 cells and increased the stimulatory effect in SK-N-MC cells. Patch-clamp experiments under non-voltage-clamped conditions revealed a significantly higher membrane potential of HEK293 than SK-N-MC cells and a reduced membrane potential after phorbol ester treatment. Lowering chloride in the uptake buffer switched the stimulatory effect of Zn(2+) in SK-N-MC cells to an inhibitory, whereas high potassium depolarization of HEK293 cells switched the inhibitory effect of Zn(2+) to a stimulatory one. This study represents the first evidence that DAT regulation by Zn(2+) is profoundly modulated by the membrane potential and chloride.
Collapse
Affiliation(s)
- Christian Pifl
- Center for Brain Research, Medical University of Vienna, Spitalgasse 4, A-1090 Vienna, Austria.
| | | | | | | | | |
Collapse
|
33
|
Rajput AH, Sitte HH, Rajput A, Fenton ME, Pifl C, Hornykiewicz O. Globus pallidus dopamine and Parkinson motor subtypes: Clinical and brain biochemical correlation. Neurology 2008; 70:1403-10. [PMID: 18172064 DOI: 10.1212/01.wnl.0000285082.18969.3a] [Citation(s) in RCA: 128] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- A H Rajput
- Division of Neurology, Department of Medicine, University of Saskatchewan/Saskatoon Health Region, Canada.
| | | | | | | | | | | |
Collapse
|
34
|
Pifl C, Sperk G. Current topics in brain dopamine research: a tribute to Professor Oleh Hornykiewicz. Wien Klin Wochenschr 2006; 118:563-5. [PMID: 17136327 DOI: 10.1007/s00508-006-0719-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Christian Pifl
- Center for Brain Research, Medical University of Vienna, Vienna, Austria.
| | | |
Collapse
|
35
|
Pifl C, Nagy G, Berényi S, Kattinger A, Reither H, Antus S. Pharmacological characterization of ecstasy synthesis byproducts with recombinant human monoamine transporters. J Pharmacol Exp Ther 2005; 314:346-54. [PMID: 15831439 DOI: 10.1124/jpet.105.084426] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [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: 11/22/2022] Open
Abstract
Ecstasy samples often contain byproducts of the illegal, uncontrolled synthesis of N-methyl-3,4-methylenedioxy-amphetamine or 3,4-methylenedioxymethamphetamine (MDMA). MDMA and eight chemically defined byproducts of MDMA synthesis were investigated for their interaction with the primary sites of action of MDMA, namely the human plasmalemmal monamine transporters for norepinephrine, serotonin, and dopamine [(norepinephrine transporter (NET), serotonin transporter (SERT), and dopamine transporter (DAT)]. SK-N-MC neuroblastoma and human embryonic kidney cells stably transfected with the transporter cDNA were used for uptake and release experiments. Two of the eight compounds, 1,3-bis (3,4-methylenedioxyphenyl)-2-propanamine (12) and N-formyl-1,3-bis (3,4-methylenedioxyphenyl)-prop-2-yl-amine (13) had uptake inhibitory potencies with IC50 values in the low micromolar range similar to MDMA. Compounds with nitro instead of amino groups and a phenylethenyl instead of a phenylethyl structure or a formamide or acetamide modification had IC50 values beyond 100 microM. MDMA, 12, and 13 were examined for induction of carrier-mediated release by superfusion of transporter expressing cells preloaded with the metabolically inert transporter substrate [3H]1-methyl-4-phenylpyridinium. MDMA induced release mediated by NET, SERT, or DAT with EC50 values of 0.64, 1.12, and 3.24 microM, respectively. 12 weakly released from NET- and SERT-expressing cells with maximum effects less than one-tenth of that of MDMA and did not release from DAT cells. 13 had no releasing activity. 12 and 13 inhibited release induced by MDMA, and the concentration dependence of this effect correlated with their uptake inhibitory potency at the various transporters. These results do not support a neurotoxic potential of the examined ecstasy synthesis byproducts and provide interesting structure-activity relationships on the transporters.
Collapse
Affiliation(s)
- Christian Pifl
- Center for Brain Research, Medical University of Vienna, Spitalgasse 4, A-1090 Vienna, Austria.
| | | | | | | | | | | |
Collapse
|
36
|
Xu J, Zhong N, Wang H, Elias JE, Kim CY, Woldman I, Pifl C, Gygi SP, Geula C, Yankner BA. The Parkinson's disease-associated DJ-1 protein is a transcriptional co-activator that protects against neuronal apoptosis. Hum Mol Genet 2005; 14:1231-41. [PMID: 15790595 DOI: 10.1093/hmg/ddi134] [Citation(s) in RCA: 205] [Impact Index Per Article: 10.8] [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: 01/11/2023] Open
Abstract
Mutations in the DJ-1 gene cause early-onset autosomal recessive Parkinson's disease (PD), although the role of DJ-1 in the degeneration of dopaminergic neurons is unresolved. Here we show that the major interacting-proteins with DJ-1 in dopaminergic neuronal cells are the nuclear proteins p54nrb and pyrimidine tract-binding protein-associated splicing factor (PSF), two multifunctional regulators of transcription and RNA metabolism. PD-associated DJ-1 mutants exhibit decreased nuclear distribution and increased mitochondrial localization, resulting in diminished co-localization with co-activator p54nrb and repressor PSF. Unlike pathogenic DJ-1 mutants, wild-type DJ-1 acts to inhibit the transcriptional silencing activity of the PSF. In addition, the transcriptional silencer PSF induces neuronal apoptosis, which can be reversed by wild-type DJ-1 but to a lesser extent by PD-associated DJ-1 mutants. DJ-1-specific small interfering RNA sensitizes cells to PSF-induced apoptosis. Both DJ-1 and p54nrb block oxidative stress and mutant alpha-synuclein-induced cell death. Thus, DJ-1 is a neuroprotective transcriptional co-activator that may act in concert with p54nrb and PSF to regulate the expression of a neuroprotective genetic program. Mutations that impair the transcriptional co-activator function of DJ-1 render dopaminergic neurons vulnerable to apoptosis and may contribute to the pathogenesis of PD.
Collapse
Affiliation(s)
- Jin Xu
- Department of Neurology, Caritas St Elizabeth's Center, Tufts University School of Medicine, Boston, MA 02135, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
37
|
Woldman I, Reither H, Kattinger A, Hornykiewicz O, Pifl C. Dopamine inhibits cell growth and cell cycle by blocking ribonucleotide reductase. Neuropharmacology 2005; 48:525-37. [PMID: 15755480 DOI: 10.1016/j.neuropharm.2004.11.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [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: 07/07/2004] [Revised: 10/15/2004] [Accepted: 11/27/2004] [Indexed: 01/08/2023]
Abstract
Dopamine (DA) is a classical neurotransmitter modulating various brain functions by acting on its specific receptors. In addition, DA is a reactive molecule that has been implicated in neurodegeneration, especially in Parkinson's disease. Here we show that DA inhibited cell growth of dopamine transporter transfected cells by intracellularly blocking cell cycle progression. To pinpoint the site of this effect, we measured DNA distribution and 5-bromo-2'-deoxyuridine (BrdU) incorporation, as well as the levels of the key cell cycle proteins. DA increased number of cells with a G1 DNA content, decreased BrdU incorporation and simultaneously increased cyclin A but had no effect on cyclin D2, D3, E, nor on cdk4 and p21. These results narrowed down the DA effect to the beginning of S phase, suggesting inhibition of the ribonucleotide reductase, an enzyme essential for DNA synthesis. Indeed, measurement of enzyme activity in situ revealed that DA, within 1h of addition to cells labelled with [3H]cytidine, strongly reduced the cell content of [3H]2'-deoxycytidine 5'-triphophate. The time course of this DA effect preceded the cell cycle progression. This novel molecular mechanism of intracellular DA action independent of plasmamembrane receptors may be involved in processes controlling the development and survival of brain dopaminergic neurons.
Collapse
Affiliation(s)
- Irina Woldman
- Center for Brain Research, Medical University of Vienna, Spitalgasse 4, A-1090 Vienna, Austria
| | | | | | | | | |
Collapse
|
38
|
Rajput AH, Fenton ME, Di Paolo T, Sitte H, Pifl C, Hornykiewicz O. Human brain dopamine metabolism in levodopa-induced dyskinesia and wearing-off. Parkinsonism Relat Disord 2004; 10:221-6. [PMID: 15120096 DOI: 10.1016/j.parkreldis.2004.01.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [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] [Received: 11/03/2003] [Revised: 01/22/2004] [Accepted: 01/23/2004] [Indexed: 11/17/2022]
Abstract
The objective of this study was to identify dopamine (DA) metabolism pattern in Lewy body Parkinson's disease (PD) patients with dyskinesia (Dysk) only, with wearing-off (WO) only, or no motor complications (NMC) induced by levodopa (LD). DA, homovanillic acid (HVA), 3,4-dihydroxyphenylacetic acid (DOPAC), and 3-methoxytyramine (3-MT) were measured individual basal ganglia nuclei of nine PD patients who received LD for 6-18 years. Three patients had only Dysk, three only WO, and three had neither Dysk nor WO. Biochemical measurements in PD brains were compared with four non-neurological control brains from individuals matched for age and post-mortem retrieval time. DA levels in the PD were reduced in the caudate by 87% and putamen by 99%. In the caudates, the HVA/DA molar ratio as an index of DA metabolism was similar in the WO and the Dysk patients. However, in the putamen, the ratio of HVA/DA was significantly higher in the WO compared with the Dysk (p = 0.03)and the NMC (p = 0.04) groups of patients. In the putamen, the DOPAC levels were higher in the WO cases while in the Dysk cases, 3-MT levels were higher. The results suggest that in the WO only cases, the putaminal DA was in large measure metabolized intraneuronally while the DA metabolism in our Dysk only patients was mainly extraneuronal. We conclude that the magnitude and the site (intra vs. extraneuronal) of the synaptic DA metabolism in the putamen plays a significant role in LD-induced Dysk and WO.
Collapse
Affiliation(s)
- Ali H Rajput
- Division of Neurology, University of Saskatchewan and Saskatoon Health Region, Rm 1663, Royal University Hospital, 103 Hospital Drive, Saskatoon, Saskatchewan, Canada S7N 0W8.
| | | | | | | | | | | |
Collapse
|
39
|
Pifl C, Khorchide M, Kattinger A, Reither H, Hardy J, Hornykiewicz O. alpha-Synuclein selectively increases manganese-induced viability loss in SK-N-MC neuroblastoma cells expressing the human dopamine transporter. Neurosci Lett 2004; 354:34-7. [PMID: 14698476 DOI: 10.1016/j.neulet.2003.09.064] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [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: 11/16/2022]
Abstract
The established or potentially toxic agents implicated in the nigral cell death in Parkinson's disease, dopamine, 1-methyl-4-phenylpyridinium (MPP(+)), iron, and manganese, were examined as to their effects on the viability of cells overexpressing alpha-synuclein. SK-N-MC neuroblastoma cells stably expressing the human dopamine transporter were transfected with human alpha-synuclein and cell clones with and without alpha-synuclein immunoreactivity were obtained. Cells were exposed for 24-72 h to 1-10 microM dopamine, 0.1-3 microM MPP(+), 0.1-1 mM FeCl(2) or 30-300 microM MnCl(2) added to the culture medium. There was no difference between cells expressing alpha-synuclein and control cells after exposure to dopamine, MPP(+) or FeCl(2). However, MnCl(2) resulted in a significantly stronger decreased viability of cells overexpressing alpha-synuclein after 72 h. These findings suggest that manganese may co-operate with alpha-synuclein in triggering neuronal cell death such as seen in manganese parkinsonism. The relevance of our observations for the pathoetiology of Parkinson's disease proper remains to be determined.
Collapse
Affiliation(s)
- Christian Pifl
- Brain Research Institute, University of Vienna, Spitalgasse 4, A-1090 Vienna, Austria.
| | | | | | | | | | | |
Collapse
|
40
|
Pifl C, Rebernik P, Kattinger A, Reither H. Zn2+ modulates currents generated by the dopamine transporter: parallel effects on amphetamine-induced charge transfer and release. Neuropharmacology 2004; 46:223-31. [PMID: 14680760 DOI: 10.1016/j.neuropharm.2003.09.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The psychostimulant drug amphetamine increases extracellular monamines in the brain acting on neurotransmitter transporters, especially the dopamine transporter. Mediated by this plasmalemmal pump, amphetamine does not only induce release but also charge transfer which might be involved in the release mechanism. To study a potential link between the two phenomena, we used Zn(2+) as an acute regulatory agent which modulates dopamine uptake by a direct interaction with the transporter protein. Charge transfer was investigated in patch-clamp experiments on HEK 293 cells stably expressing the human dopamine transporter, release was studied in superfusion experiments on cells preloaded with the metabolically inert transporter substrate [(3)H]1-methyl-4-phenylpyridinium. Ten micromoles of Zn(2+) had only minor effects in the absence of amphetamine but stimulated release and inward currents induced by amphetamine depending on the concentration of the psychostimulant: the effect of 0.2 microM was not significantly modulated, whereas the effect of 1 and 10 microM amphetamine was stimulated, and the stimulation by Zn(2+) was significantly stronger at 10 microM than at 1 microM amphetamine. The stimulatory action of Zn(2+) on release and inward current was in contrast to its inhibitory action on dopamine uptake. This supports a release mechanism of amphetamine different from facilitated exchange diffusion but involving ion fluxes through the dopamine transporter.
Collapse
Affiliation(s)
- Christian Pifl
- Division of Biochemistry and Molecular Biology, Brain Research Institute, University of Vienna, Spitalgasse 4, Vienna A-1090, Austria.
| | | | | | | |
Collapse
|
41
|
Abstract
Cell cycle blockers inhibit growth in dividing cells, but promote survival of differentiated cells, including neurons. Low micromolar dopamine profoundly inhibited cell growth in dopamine transporter transfected SK-N-MC neuroblastoma cells by cell cycle arrest at G(1). This effect was independent of oxy radical formation, antagonized by transporter block, abolished by FeCl(3) and mimicked by the iron chelator deferoxamine. We propose that dopamine inhibits cell growth by its ability to chelate intracellular iron. This novel biological action unrelated to neurotransmitter receptors, second messengers or oxidative stress, observed in human neuroblastoma cells of striatal origin, may be important for cell differentiation during neurodevelopment and survival of differentiated dopamine (nigral) neurons.
Collapse
Affiliation(s)
- Christian Pifl
- Brain Research Institute, University of Vienna, Spitalgasse 4, 1090, Vienna, Austria.
| | | | | | | |
Collapse
|
42
|
Abstract
Reuptake of extracellular noradrenaline (NA) into superior cervical ganglion (SCG) neurones is mediated by means of the noradrenaline transporter (NAT, uptake 1). We now demonstrate by single-cell RT-PCR that mRNA of the organic cation transporter 3 (OCT3, uptake 2) occurs in rat SCG neurones as well. Furthermore, our RT-PCR analyses reveal the presence of mRNA for novel organic cation transporters 1 and 2 (OCTN1 and OCTN2), but not for OCT1 or OCT2 in the ganglion. Making use of the NAT as a powerful, neurone-specific transporter system, we loaded[3H]-N-methyl-4-phenylpyridinium ([3H]-MPP+) into cultured rat SCG neurones. The ensuing radioactive outflow from these cultures was enhanced by desipramine and reserpine, but reduced (in the presence of desipramine) by the OCT3 inhibitors cyanine 863, oestradiol and corticosterone. In contrast, cyanine 863 enhanced the radioactive outflow from cultures preloaded with [3H]-NA. Two observations suggest that a depletion of storage vesicles by cyanine 863 accounts for the latter phenomenon: first, the primary radioactive product isolated from supernatants of cultures loaded with [3H]-NA was the metabolite [3H]-DHPG; and second, inhibition of MAO significantly reduced the radioactive outflow in response to cyanine 863. The outflow of [3H]-MPP+ was significantly enhanced by MPP+, guanidine, choline and amantadine as potential substrates for OCT-related transmembrane transporters. However, desipramine at a low concentration essentially blocked the radioactive outflow induced by all of these substances with the exception of MPP+, indicating the NAT and not an OCT as their primary site of action. The MPP+-induced release of [3H]-MPP+ was fully prevented by a combined application of desipramine and cyanine 863. No trans-stimulation of [3H]-MPP+ outflow was observed by the OCTN1 and OCTN2 substrate carnitine at 100 microM. Our observations indicate an OCT-mediated transmembrane transport of [3H]-MPP+. Amongst the three OCTs expressed in the SCG, OCT3 best fits the profile of substrates and antagonists that cause trans-stimulation and trans-inhibition, respectively, of [3H]-MPP+ release.
Collapse
Affiliation(s)
- Doris Kristufek
- Brain Research Institute, University of Vienna, Spitalgasse 4, A-1090 Vienna, Austria
| | | | | | | |
Collapse
|
43
|
Pifl C, Zezula J, Spittler A, Kattinger A, Reither H, Caron MG, Hornykiewicz O. Antiproliferative action of dopamine and norepinephrine in neuroblastoma cells expressing the human dopamine transporter. FASEB J 2001; 15:1607-9. [PMID: 11427501 DOI: 10.1096/fj.00-0738fje] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- C Pifl
- Brain Research Institute, Pharmacological Institute and. Department of Surgery, University of Vienna, 1090 Vienna, Austria.
| | | | | | | | | | | | | |
Collapse
|
44
|
Sitte HH, Hiptmair B, Zwach J, Pifl C, Singer EA, Scholze P. Quantitative analysis of inward and outward transport rates in cells stably expressing the cloned human serotonin transporter: inconsistencies with the hypothesis of facilitated exchange diffusion. Mol Pharmacol 2001; 59:1129-37. [PMID: 11306696 DOI: 10.1124/mol.59.5.1129] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.6] [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: 11/22/2022] Open
Abstract
Quantitative aspects of inward and outward transport of substrates by the human plasmalemmal serotonin transporter (hSERT) were investigated. Uptake and superfusion experiments were performed on human embryonic kidney 293 cells permanently expressing the hSERT using [(3)H]serotonin (5-HT) and [(3)H]1-methyl-4-phenylpyridinium (MPP(+)) as substrates. Saturation analyses rendered K(m) values of 0.60 and 17.0 microM for the uptake of [(3)H]5-HT and [(3)H]MPP(+), respectively. Kinetic analysis of outward transport was performed by prelabeling the cells with increasing concentrations of the two substrates and exposing them to a saturating concentration of p-chloroamphetamine (PCA; 10 microM). Apparent K(m) values for PCA induced transport were 564 microM and about 7 mM intracellular [(3)H]5-HT and [(3)H]MPP(+), respectively. Lowering the extracellular Na(+) concentrations in uptake and superfusion experiments revealed differential effects on substrate transport: at 10 mM Na(+) the K(m) value for [(3)H]5-HT uptake increased approximately 5-fold and the V(max) value remained unchanged. The K(m) value for [(3)H]MPP(+) uptake also increased, but the V(max) value was reduced by 50%. When efflux was studied at saturating prelabeling conditions of both substrates, PCA as well as unlabeled 5-HT and MPP(+) (all substances at saturating concentrations) induced the same efflux at 10 mM and 120 mM Na(+). Thus, notwithstanding a 50% reduction in the V(max) value of transport into the cell, MPP(+) was still able to induce maximal outward transport of either substrate. Thus, hSERT-mediated inward and outward transport seems to be independently modulated and may indicate inconsistencies with the classical model of facilitated exchange diffusion.
Collapse
Affiliation(s)
- H H Sitte
- Institute of Pharmacology, University of Vienna, Vienna, Austria
| | | | | | | | | | | |
Collapse
|
45
|
Scholze P, Zwach J, Kattinger A, Pifl C, Singer EA, Sitte HH. Transporter-mediated release: a superfusion study on human embryonic kidney cells stably expressing the human serotonin transporter. J Pharmacol Exp Ther 2000; 293:870-8. [PMID: 10869387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
HEK 293 cells stably expressing the human serotonin transporter (hSERT) were grown on coverslips, preincubated with [(3)H]5-hydroxytryptamine (5-HT), and superfused. Substrates of the hSERT [e.g., p-chloroamphetamine (PCA)], increased the basal efflux of [(3)H]5-HT in a concentration-dependent manner. 5-HT reuptake blockers (e.g., imipramine, paroxetine) also raised [(3)H]5-HT efflux, reaching approximately one-third of the maximal effect of the hSERT substrates. In uptake experiments, both groups of substances inhibited [(3)H]5-HT uptake. Using the low-affinity substrate [(3)H]N-methyl-4-phenylpyridinium (MPP(+)) to label the cells in superfusion experiments, reuptake inhibitors failed to enhance efflux. Similar results were obtained using human placental choriocarcinoma (JAR) cells that constitutively express the hSERT at a low level. By contrast, PCA raised [(3)H]MPP(+) efflux in both types of cells, and its effect was inhibited by paroxetine. The addition of the Na(+),K(+)-ATPase inhibitor ouabain (100 microM) to the superfusion buffer enhanced basal efflux of [(3)H]5-HT-loaded hSERT cells by approximately 2-fold; the effect of PCA (10 microM) was strongly augmented by ouabain, whereas the effect of imipramine was not. The Na(+)/H(+) ionophore monensin (10 microM) also augmented the effect of PCA on efflux of [(3)H]5-HT as well as on efflux of [(3)H]MPP(+). In [(3)H]5-HT-labeled cells, the combination of imipramine and monensin raised [(3)H]5-HT efflux to a greater extent than either of the two substances alone. In [(3)H]MPP(+)-labeled cells, imipramine had no effect on its own and fully reversed the effect of monensin. The results suggest that the [(3)H]5-HT efflux caused by uptake inhibitors is entirely due to interrupted high-affinity reuptake, which is ongoing even under superfusion conditions.
Collapse
Affiliation(s)
- P Scholze
- Department of Pharmacology, University of Vienna, Austria.
| | | | | | | | | | | |
Collapse
|
46
|
Sitte HH, Scholze P, Schloss P, Pifl C, Singer EA. Characterization of carrier-mediated efflux in human embryonic kidney 293 cells stably expressing the rat serotonin transporter: a superfusion study. J Neurochem 2000; 74:1317-24. [PMID: 10693966 DOI: 10.1046/j.1471-4159.2000.741317.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.7] [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: 11/20/2022]
Abstract
Human embryonic kidney 293 cells stably transfected with the rat plasmalemmal serotonin transporter (rSERT) were incubated with 5-[3H]hydroxytryptamine ([3H]5-HT) and superfused. Substrates of the rSERT, such as p-chloroamphetamine (PCA) or methylenedioxymethamphetamine, concentration-dependently increased basal efflux of [3H]5-HT. 5-HT reuptake blockers (e.g., imipramine, citalopram) also caused an enhancement of [3H]5-HT efflux, reaching about half the maximal effect of the rSERT substrates. In uptake experiments, both groups of substances concentration-dependently inhibited 5-HT uptake. EC50 values obtained in superfusion experiments significantly correlated with IC50 values from uptake studies (r2 = 0.92). Addition of the Na+,K(+)-ATPase inhibitor ouabain (100 microM) to or the omission of K+ from the superfusion buffer accelerated basal efflux. The effect of PCA (10 microM) was markedly enhanced by both measures, whereas the effect of uptake inhibitors remained unchanged. When [3H]MPP+, a substrate with low affinity for the rSERT, was used instead of [3H]5-HT for labeling the cells, uptake inhibitors failed to augment efflux. By contrast, PCA accelerated [3H]MPP+ efflux, and its effect was strongly enhanced in the presence of ouabain. The results suggest that the [3H]5-HT efflux caused by substrates of rSERT is carrier-mediated, whereas efflux induced by uptake inhibitors is a consequence of interrupted high-affinity reuptake that is ongoing even under superfusion conditions.
Collapse
Affiliation(s)
- H H Sitte
- Department of Pharmacology, University of Vienna, Austria
| | | | | | | | | |
Collapse
|
47
|
Pifl C, Singer EA. Ion dependence of carrier-mediated release in dopamine or norepinephrine transporter-transfected cells questions the hypothesis of facilitated exchange diffusion. Mol Pharmacol 1999; 56:1047-54. [PMID: 10531412 DOI: 10.1124/mol.56.5.1047] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The mechanism of release mediated by the human dopamine and norepinephrine transporter (DAT and NET, respectively) was studied by a superfusion technique in human embryonic kidney 293 cells stably transfected with the respective transporter cDNA and loaded with the metabolically inert substrate [(3)H]1-methyl-4-phenylpyridinium. Release was induced by amphetamine, dopamine, and norepinephrine or by lowering the sodium or chloride concentration in the superfusion buffer (iso-osmotic replacement by lithium and isethionate, respectively). Efflux of [(3)H]1-methyl-4-phenylpyridinium was analyzed at 30-s time resolution. In both transporters, release induced by the substrates amphetamine, dopamine, and norepinephrine followed the same time course as release induced by the removal of chloride and was faster than that caused by the removal of sodium. In the presence of low sodium (DAT: 10 mM; NET: 5 mM) none of the substrates was able to induce release from either type of cell, but adding back sodium to control conditions promptly restored the releasing action. In the presence of low chloride (DAT: 3 mM; NET: 2 mM), however, amphetamine as well as the catecholamines stimulated release from both types of cell. In contrast with the ion dependence of release observed in superfusion experiments, uptake initial rates of substrates at concentrations used in release experiments were the same or even higher at low sodium than at low chloride. The results indicate a decisive role of extracellular sodium for carrier-mediated release unrelated to the sodium-dependent uptake of the releasing substrate, and suggest a release mechanism different from simple exchange diffusion considering only the amines as substrates.
Collapse
Affiliation(s)
- C Pifl
- Institute of Biochemical Pharmacology, University of Vienna, Vienna, Austria.
| | | |
Collapse
|
48
|
Furukawa Y, Nygaard TG, Gütlich M, Rajput AH, Pifl C, DiStefano L, Chang LJ, Price K, Shimadzu M, Hornykiewicz O, Haycock JW, Kish SJ. Striatal biopterin and tyrosine hydroxylase protein reduction in dopa-responsive dystonia. Neurology 1999; 53:1032-41. [PMID: 10496263 DOI: 10.1212/wnl.53.5.1032] [Citation(s) in RCA: 95] [Impact Index Per Article: 3.8] [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: 11/15/2022] Open
Abstract
OBJECTIVE To determine the mechanism leading to striatal dopamine (DA) loss in dopa-responsive dystonia (DRD). BACKGROUND Although mutations in the gene GCH1, coding for the tetrahydrobiopterin (BH4) biosynthetic enzyme guanosine triphosphate-cyclohydrolase I, have been identified in some patients with DRD, the actual status of brain BH4 (the cofactor for tyrosine hydroxylase [TH]) is unknown. METHODS The authors sequenced GCH1 and measured levels of total biopterin (BP) and total neopterin (NP), TH, and dopa decarboxylase (DDC) proteins, and the DA and vesicular monoamine transporters (DAT, VMAT2) in autopsied brain of two patients with typical DRD. RESULTS Patient 1 had two GCH1 mutations but Patient 2 had no mutation in the coding region of this gene. Striatal BP levels were markedly reduced (<20% of control subjects) in both patients and were also low in two conditions characterized by degeneration of nigrostriatal DA neurons (PD and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine treated primate), whereas brain NP concentrations were selectively decreased (<45%) in the DRD patients. In the putamen, both DRD patients had severely reduced (<3%) TH protein levels but had normal concentrations of DDC protein, DAT, and VMAT2. CONCLUSIONS The data suggest that 1) brain BH4 is decreased substantially in dopa-responsive dystonia, 2) dopa-responsive dystonia can be distinguished from degenerative nigrostriatal dopamine deficiency disorders by the presence of reduced brain neopterin, and 3) the striatal dopamine reduction in dopa-responsive dystonia is caused by decreased TH activity due to low cofactor concentration and to actual loss of TH protein. This reduction of TH protein, which might be explained by reduced enzyme stability/expression consequent to congenital BH4 deficiency, can be expected to limit the efficacy of acute BH4 administration on dopamine biosynthesis in dopa-responsive dystonia.
Collapse
Affiliation(s)
- Y Furukawa
- Human Neurochemical Pathology Laboratory, Centre for Addiction and Mental Health, The Clarke Division, Toronto, Ontario, Canada
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
49
|
Pifl C, Agneter E, Drobny H, Sitte HH, Singer EA. Amphetamine reverses or blocks the operation of the human noradrenaline transporter depending on its concentration: superfusion studies on transfected cells. Neuropharmacology 1999; 38:157-65. [PMID: 10193907 DOI: 10.1016/s0028-3908(98)00155-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [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: 11/24/2022]
Abstract
Whether amphetamine enhances noradrenergic activity by uptake blockade or a releasing action is still a matter of debate. In order to gain insight into the interaction of amphetamine with the noradrenaline transporter its cDNA was transfected into COS-7 cells (NAT-cells) or cotransfected with the cDNA of the vesicular monoamine transporter (NAT/VMAT-cells); cells were loaded with [3H]noradrenaline, superfused and the efflux analysed for total tritium and [3H]noradrenaline. In NAT-cells amphetamine stimulated [3H]noradrenaline efflux concentration-dependently when added to the superfusion buffer at 0.01, 0.1 and 1 microM. By contrast, 10 or 100 microM amphetamine stimulated efflux to a smaller extent or not at all; however, on switching back to amphetamine-free buffer a prompt increase of efflux was observed. Cocaine did not increase efflux per se and blocked the amphetamine-induced efflux. In NAT/VMAT-cells amphetamine stimulated efflux in a concentration-dependent manner. The effect showed saturation at 1 microM and was not suppressed at higher concentrations. Cocaine also elicited efflux from NAT/VMAT-cells concentration-dependently; the maximum was reached at approximately 1 microM and amounted to only about half of the amphetamine-induced efflux. It is concluded that amphetamine can induce noradrenaline transporter mediated release only at high nanomolar to low micromolar concentrations. At higher concentrations it blocks the noradrenaline transporter; in this case, the releasing action of amphetamine, like that of cocaine, is dependent on a vesicular pool of noradrenaline.
Collapse
Affiliation(s)
- C Pifl
- Institute of Biochemical Pharmacology, University of Vienna, Austria.
| | | | | | | | | |
Collapse
|
50
|
Sitte HH, Huck S, Reither H, Boehm S, Singer EA, Pifl C. Carrier-mediated release, transport rates, and charge transfer induced by amphetamine, tyramine, and dopamine in mammalian cells transfected with the human dopamine transporter. J Neurochem 1998; 71:1289-97. [PMID: 9721755 DOI: 10.1046/j.1471-4159.1998.71031289.x] [Citation(s) in RCA: 161] [Impact Index Per Article: 6.2] [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: 11/20/2022]
Abstract
Amphetamine and related substances induce dopamine release. According to a traditional explanation, this dopamine release occurs in exchange for amphetamine by means of the dopamine transporter (DAT). We tested this hypothesis in human embryonic kidney 293 cells stably transfected with the human DAT by measuring the uptake of dopamine, tyramine, and D- and L-amphetamine as well as substrate-induced release of preloaded N-methyl-4-[3H]phenylpyridinium ([3H]MPP+). The uptake of substrates was sodium-dependent and was inhibited by ouabain and cocaine, which also prevented substrate-induced release of MPP+. Patch-clamp recordings revealed that all four substrates elicited voltage-dependent inward currents (on top of constitutive leak currents) that were prevented by cocaine. Whereas individual substrates had similar affinities in release, uptake, and patch-clamp experiments, maximal effects displayed remarkable differences. Hence, maximal effects in release and current induction were approximately 25% higher for D-amphetamine as compared with the other substrates. By contrast, dopamine was the most efficacious substrate in uptake experiments, with its maximal initial uptake rate exceeding those of amphetamine and tyramine by factors of 20 and 4, respectively. Our experiments indicate a poor correlation between substrate-induced release and the transport of substrates, whereas the ability of substrates to induce currents correlates well with their releasing action.
Collapse
Affiliation(s)
- H H Sitte
- Institute of Biochemical Pharmacology, University of Vienna, Austria
| | | | | | | | | | | |
Collapse
|