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Deng IB, Follett J, Fox JD, Farrer MJ. Characterization of Dnajc12 knockout mice, a model of hypodopaminergia. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.06.602343. [PMID: 39026821 PMCID: PMC11257452 DOI: 10.1101/2024.07.06.602343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/20/2024]
Abstract
Homozygous DNAJC12 c.79-2A>G (p. V27Wfs*14) loss-of-function mutations were first reported as a cause of young-onset Parkinson's disease. However, bi-allelic autosomal recessive pathogenic variants in DNAJC12 may lead to an alternative constellation of neurological features including infantile dystonia, developmental delay, intellectual disability and neuropsychiatric disorders. DNAJC12 is understood to co-chaperone aromatic amino acid hydroxylases to enhance the synthesis of biogenic amines. In vitro , we confirm overexpressed DNAJC12 forms a complex with tyrosine hydroxylase, the rate-limiting enzyme in dopamine (DA) synthesis. Now we describe a conditional knockout mouse (cDKO) in which loxP sites flanking Dnajc12 exon 2 enable its excision by cre-recombinase to create a constitutive Dnajc12 knock out (DKO). At three months of age, DKO animals exhibit reduced locomotion and exploratory behavior in automated open-field testing. DKO mice also manifest increased plasma phenylalanine levels, a cardinal feature of patients with DNAJC12 pathogenic variants. In striatal tissue, total DA and serotonin, and their metabolites, are reduced. Biochemical alterations in synaptic proteins and tyrosine hydroxylase are also apparent, with enhanced phosphorylation of pSer31 and pSer40 sites that may reflect biological compensation. Electrically-evoked striatal DA is reduced. Most immediately, cDKO and DKO mice present models to develop and refined therapeutic approaches for the treatment of DNAJC12 dystonia and parkinsonism. These models may also enable the pleiotropic functions of biogenic amines (including DA) to be individually investigated in the brain and periphery.
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Franco R, Serrano-Marín J, Navarro G, Rivas-Santisteban R. The NADPH Link between the Renin Angiotensin System and the Antioxidant Mechanisms in Dopaminergic Neurons. Antioxidants (Basel) 2023; 12:1869. [PMID: 37891948 PMCID: PMC10604245 DOI: 10.3390/antiox12101869] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Revised: 10/10/2023] [Accepted: 10/13/2023] [Indexed: 10/29/2023] Open
Abstract
The renin angiotensin system (RAS) has several components including signaling peptides, enzymes, and membrane receptors. The effort in characterizing this system in the periphery has led to the approval of a class of antihypertensives. Much less is known about RAS in the central nervous system. The production of RAS peptides and the expression of several RAS enzymes and receptors in dopaminergic neurons of the substantia nigra has raised expectations in the therapy of Parkinson's disease, a neurodegenerative condition characterized by lack of dopamine in the striatum, the motor control region of the mammalian brain. On the one hand, dopamine production requires reducing power. On the other hand, reducing power is required by mechanisms involved in REDOX homeostasis. This review focuses on the potential role of RAS in the regulation of neuronal/glial expression of glucose-6-phosphate dehydrogenase, which produces the NADPH required for dopamine synthesis and for reactive oxygen species (ROS) detoxification. It is known that transgenic expression of the gene coding for glucose-6-phosphate dehydrogenase prevents the death of dopaminergic nigral neurons. Signaling via angiotensin II G protein-coupled receptors, AT1 or AT2, leads to the activation of protein kinase A and/or protein kinase C that in turn can regulate glucose-6- phosphate dehydrogenase activity, by Ser/Thr phosphorylation/dephosphorylation events. Long-term effects of AT1 or AT2 receptor activation may also impact on the concentration of the enzyme via activation of transcription factors that participate in the regulation of gene expression in neurons (or glia). Future research is needed to determine how the system can be pharmacologically manipulated to increase the availability of NADPH to neurons degenerating in Parkinson's disease and to neuroprotective glia.
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Affiliation(s)
- Rafael Franco
- Department of Biochemistry and Molecular Biomedicine, School of Biology, Universitat de Barcelona, 08028 Barcelona, Spain
- CiberNed, Network Center for Neurodegenerative Diseases, Spanish National Health Institute Carlos III, 28029 Madrid, Spain;
- School of Chemistry, Universitat de Barcelona, 08028 Barcelona, Spain
| | - Joan Serrano-Marín
- Department of Biochemistry and Molecular Biomedicine, School of Biology, Universitat de Barcelona, 08028 Barcelona, Spain
| | - Gemma Navarro
- CiberNed, Network Center for Neurodegenerative Diseases, Spanish National Health Institute Carlos III, 28029 Madrid, Spain;
- Department of Biochemistry and Physiology, School of Pharmacy and Food Science, Universitat de Barcelona, 08028 Barcelona, Spain
- Institute of Neurosciences, Universitat de Barcelona, 08007 Barcelona, Spain
| | - Rafael Rivas-Santisteban
- CiberNed, Network Center for Neurodegenerative Diseases, Spanish National Health Institute Carlos III, 28029 Madrid, Spain;
- Campus Bellaterra, Autonomous University of Barcelona, Cerdanyola del Vallés, 08193 Barcelona, Spain
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Majkutewicz I. Dimethyl fumarate: A review of preclinical efficacy in models of neurodegenerative diseases. Eur J Pharmacol 2022; 926:175025. [DOI: 10.1016/j.ejphar.2022.175025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Revised: 04/27/2022] [Accepted: 05/09/2022] [Indexed: 11/03/2022]
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Fanet H, Capuron L, Castanon N, Calon F, Vancassel S. Tetrahydrobioterin (BH4) Pathway: From Metabolism to Neuropsychiatry. Curr Neuropharmacol 2021; 19:591-609. [PMID: 32744952 PMCID: PMC8573752 DOI: 10.2174/1570159x18666200729103529] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 07/03/2020] [Accepted: 07/23/2020] [Indexed: 11/22/2022] Open
Abstract
Tetrahydrobipterin (BH4) is a pivotal enzymatic cofactor required for the synthesis of serotonin, dopamine and nitric oxide. BH4 is essential for numerous physiological processes at periphery and central levels, such as vascularization, inflammation, glucose homeostasis, regulation of oxidative stress and neurotransmission. BH4 de novo synthesis involves the sequential activation of three enzymes, the major controlling point being GTP cyclohydrolase I (GCH1). Complementary salvage and recycling pathways ensure that BH4 levels are tightly kept within a physiological range in the body. Even if the way of transport of BH4 and its ability to enter the brain after peripheral administration is still controversial, data showed increased levels in the brain after BH4 treatment. Available evidence shows that GCH1 expression and BH4 synthesis are stimulated by immunological factors, notably pro-inflammatory cytokines. Once produced, BH4 can act as an anti- inflammatory molecule and scavenger of free radicals protecting against oxidative stress. At the same time, BH4 is prone to autoxidation, leading to the release of superoxide radicals contributing to inflammatory processes, and to the production of BH2, an inactive form of BH4, reducing its bioavailability. Alterations in BH4 levels have been documented in many pathological situations, including Alzheimer's disease, Parkinson's disease and depression, in which increased oxidative stress, inflammation and alterations in monoaminergic function are described. This review aims at providing an update of the knowledge about metabolism and the role of BH4 in brain function, from preclinical to clinical studies, addressing some therapeutic implications.
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Affiliation(s)
- H. Fanet
- INRAe, Nutrition and Integrated Neurobiology, UMR 1286, Bordeaux, France
- Université de Bordeaux, Nutrition and Integrated Neurobiology, UMR 1286, Bordeaux, France
- Faculty of Pharmacy, Université Laval, Quebec City, QC, Canada
- Neurosciences Axis, Centre de Recherche du CHU de Québec-Université Laval, Quebec City, QC, Canada
- OptiNutriBrain International Associated Laboratory (NurtriNeuro France-INAF Canada), Quebec City, Canada
| | - L. Capuron
- INRAe, Nutrition and Integrated Neurobiology, UMR 1286, Bordeaux, France
- Université de Bordeaux, Nutrition and Integrated Neurobiology, UMR 1286, Bordeaux, France
- OptiNutriBrain International Associated Laboratory (NurtriNeuro France-INAF Canada), Quebec City, Canada
| | - N. Castanon
- INRAe, Nutrition and Integrated Neurobiology, UMR 1286, Bordeaux, France
- Université de Bordeaux, Nutrition and Integrated Neurobiology, UMR 1286, Bordeaux, France
- OptiNutriBrain International Associated Laboratory (NurtriNeuro France-INAF Canada), Quebec City, Canada
| | - F. Calon
- Faculty of Pharmacy, Université Laval, Quebec City, QC, Canada
- Neurosciences Axis, Centre de Recherche du CHU de Québec-Université Laval, Quebec City, QC, Canada
- OptiNutriBrain International Associated Laboratory (NurtriNeuro France-INAF Canada), Quebec City, Canada
| | - S. Vancassel
- INRAe, Nutrition and Integrated Neurobiology, UMR 1286, Bordeaux, France
- Université de Bordeaux, Nutrition and Integrated Neurobiology, UMR 1286, Bordeaux, France
- OptiNutriBrain International Associated Laboratory (NurtriNeuro France-INAF Canada), Quebec City, Canada
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α-Bisabolol, a Dietary Bioactive Phytochemical Attenuates Dopaminergic Neurodegeneration through Modulation of Oxidative Stress, Neuroinflammation and Apoptosis in Rotenone-Induced Rat Model of Parkinson's disease. Biomolecules 2020; 10:biom10101421. [PMID: 33049992 PMCID: PMC7599960 DOI: 10.3390/biom10101421] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 09/24/2020] [Accepted: 09/26/2020] [Indexed: 12/21/2022] Open
Abstract
Rotenone (ROT), a plant-derived pesticide is a well-known environmental neurotoxin associated with causation of Parkinson’s disease (PD). ROT impairs mitochondrial dysfunction being mitochondrial complex-I (MC-1) inhibitor and perturbs antioxidant-oxidant balance that contributes to the onset and development of neuroinflammation and neurodegeneration in PD. Due to the scarcity of agents to prevent the disease or to cure or halt the progression of symptoms of PD, the focus is on exploring agents from naturally occurring dietary phytochemicals. Among numerous phytochemicals, α-Bisabolol (BSB), natural monocyclic sesquiterpene alcohol found in many ornamental flowers and edible plants garnered attention due to its potent pharmacological properties and therapeutic potential. Therefore, the present study investigated the neuroprotective effects of BSB in a rat model of ROT-induced dopaminergic neurodegeneration, a pathogenic feature of PD and underlying mechanism targeting oxidative stress, inflammation and apoptosis. BSB treatment significantly prevented ROT-induced loss of dopaminergic neurons and fibers in the substantia nigra and striatum respectively. BSB treatment also attenuated ROT-induced oxidative stress evidenced by inhibition of MDA formation and GSH depletion as well as improvement in antioxidant enzymes, SOD and catalase. BSB treatment also attenuated ROT-induced activation of the glial cells as well as the induction and release of proinflammatory cytokines (IL-1β, IL-6 and TNF-α) and inflammatory mediators (iNOS and COX-2) in the striatum. In addition to countering oxidative stress and inflammation, BSB also attenuated apoptosis of dopaminergic neurons by attenuating downregulation of anti-apoptotic protein Bcl-2 and upregulation of pro-apoptotic proteins Bax, cleaved caspases-3 and 9. Further, BSB was observed to attenuate mitochondrial dysfunction by inhibiting mitochondrial lipid peroxidation, cytochrome-C release and reinstates the levels/activity of ATP and MC-I. The findings of the study demonstrate that BSB treatment salvaged dopaminergic neurons, attenuated microglia and astrocyte activation, induction of inflammatory mediators, proinflammatory cytokines and reduced the expression of pro-apoptotic markers. The in vitro study on ABTS radical revealed the antioxidant potential of BSB. The results of the present study are clearly suggestive of the neuroprotective effects of BSB through antioxidant, anti-inflammatory and anti-apoptotic properties in ROT-induced model of PD.
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Kawahata I, Fukunaga K. Degradation of Tyrosine Hydroxylase by the Ubiquitin-Proteasome System in the Pathogenesis of Parkinson's Disease and Dopa-Responsive Dystonia. Int J Mol Sci 2020; 21:ijms21113779. [PMID: 32471089 PMCID: PMC7312529 DOI: 10.3390/ijms21113779] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 05/19/2020] [Accepted: 05/25/2020] [Indexed: 12/16/2022] Open
Abstract
Nigrostriatal dopaminergic systems govern physiological functions related to locomotion, and their dysfunction leads to movement disorders, such as Parkinson’s disease and dopa-responsive dystonia (Segawa disease). Previous studies revealed that expression of the gene encoding nigrostriatal tyrosine hydroxylase (TH), a rate-limiting enzyme of dopamine biosynthesis, is reduced in Parkinson’s disease and dopa-responsive dystonia; however, the mechanism of TH depletion in these disorders remains unclear. In this article, we review the molecular mechanism underlying the neurodegeneration process in dopamine-containing neurons and focus on the novel degradation pathway of TH through the ubiquitin-proteasome system to advance our understanding of the etiology of Parkinson’s disease and dopa-responsive dystonia. We also introduce the relation of α-synuclein propagation with the loss of TH protein in Parkinson’s disease as well as anticipate therapeutic targets and early diagnosis of these diseases.
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Affiliation(s)
- Ichiro Kawahata
- Correspondence: (I.K.); (K.F.); Tel.: +81-22-795-6838 (I.K.); +81-22-795-6836 (K.F.); Fax: +81-22-795-6835 (I.K. & K.F.)
| | - Kohji Fukunaga
- Correspondence: (I.K.); (K.F.); Tel.: +81-22-795-6838 (I.K.); +81-22-795-6836 (K.F.); Fax: +81-22-795-6835 (I.K. & K.F.)
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7
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Kraft VN, Bezjian CT, Pfeiffer S, Ringelstetter L, Müller C, Zandkarimi F, Merl-Pham J, Bao X, Anastasov N, Kössl J, Brandner S, Daniels JD, Schmitt-Kopplin P, Hauck SM, Stockwell BR, Hadian K, Schick JA. GTP Cyclohydrolase 1/Tetrahydrobiopterin Counteract Ferroptosis through Lipid Remodeling. ACS CENTRAL SCIENCE 2020; 6:41-53. [PMID: 31989025 PMCID: PMC6978838 DOI: 10.1021/acscentsci.9b01063] [Citation(s) in RCA: 601] [Impact Index Per Article: 150.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Indexed: 05/03/2023]
Abstract
Ferroptosis is an iron-dependent form of regulated cell death linking iron, lipid, and glutathione levels to degenerative processes and tumor suppression. By performing a genome-wide activation screen, we identified a cohort of genes antagonizing ferroptotic cell death, including GTP cyclohydrolase-1 (GCH1) and its metabolic derivatives tetrahydrobiopterin/dihydrobiopterin (BH4/BH2). Synthesis of BH4/BH2 by GCH1-expressing cells caused lipid remodeling, suppressing ferroptosis by selectively preventing depletion of phospholipids with two polyunsaturated fatty acyl tails. GCH1 expression level in cancer cell lines stratified susceptibility to ferroptosis, in accordance with its expression in human tumor samples. The GCH1-BH4-phospholipid axis acts as a master regulator of ferroptosis resistance, controlling endogenous production of the antioxidant BH4, abundance of CoQ10, and peroxidation of unusual phospholipids with two polyunsaturated fatty acyl tails. This demonstrates a unique mechanism of ferroptosis protection that is independent of the GPX4/glutathione system.
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Affiliation(s)
- Vanessa
A. N. Kraft
- Institute
of Molecular Toxicology and Pharmacology, Genetics and Cellular Engineering
Group, HelmholtzZentrum Muenchen, Ingolstaedter Landstr. 1, 85764 Neuherberg, Germany
| | - Carla T. Bezjian
- Department
of Chemistry, Columbia University, 550 West 120th Street, MC4846, New York, New York 10027, United States
| | - Susanne Pfeiffer
- Institute
of Molecular Toxicology and Pharmacology, Genetics and Cellular Engineering
Group, HelmholtzZentrum Muenchen, Ingolstaedter Landstr. 1, 85764 Neuherberg, Germany
| | - Larissa Ringelstetter
- Institute
of Molecular Toxicology and Pharmacology, Assay Development and Screening
Platform, HelmholtzZentrum Muenchen, Ingolstaedter Landstr. 1, 85764 Neuherberg, Germany
| | - Constanze Müller
- Research
Unit Analytical BioGeoChemistry, HelmholtzZentrum
Muenchen, Ingolstaedter Landstr. 1, 85764 Neuherberg, Germany
| | - Fereshteh Zandkarimi
- Department
of Biological Sciences, Columbia University, New York, New York 10027, United States
| | - Juliane Merl-Pham
- Research
Unit Protein Science, HelmholtzZentrum Muenchen, Ingolstaedter Landstr. 1, 85764 Neuherberg, Germany
| | - Xuanwen Bao
- Institute
of Radiation Biology, HelmholtzZentrum Muenchen, Ingolstaedter Landstr. 1, 85764 Neuherberg, Germany
| | - Natasa Anastasov
- Institute
of Radiation Biology, HelmholtzZentrum Muenchen, Ingolstaedter Landstr. 1, 85764 Neuherberg, Germany
| | - Johanna Kössl
- Institute
of Molecular Toxicology and Pharmacology, Genetics and Cellular Engineering
Group, HelmholtzZentrum Muenchen, Ingolstaedter Landstr. 1, 85764 Neuherberg, Germany
| | - Stefanie Brandner
- Institute
of Molecular Toxicology and Pharmacology, Assay Development and Screening
Platform, HelmholtzZentrum Muenchen, Ingolstaedter Landstr. 1, 85764 Neuherberg, Germany
| | - Jacob D. Daniels
- Department
of Pharmacology, Columbia University, New York, New York 10027, United States
| | - Philippe Schmitt-Kopplin
- Research
Unit Analytical BioGeoChemistry, HelmholtzZentrum
Muenchen, Ingolstaedter Landstr. 1, 85764 Neuherberg, Germany
| | - Stefanie M. Hauck
- Research
Unit Protein Science, HelmholtzZentrum Muenchen, Ingolstaedter Landstr. 1, 85764 Neuherberg, Germany
| | - Brent R. Stockwell
- Department
of Chemistry, Columbia University, 550 West 120th Street, MC4846, New York, New York 10027, United States
- Department
of Biological Sciences, Columbia University, New York, New York 10027, United States
- E-mail:
| | - Kamyar Hadian
- Institute
of Molecular Toxicology and Pharmacology, Assay Development and Screening
Platform, HelmholtzZentrum Muenchen, Ingolstaedter Landstr. 1, 85764 Neuherberg, Germany
- E-mail:
| | - Joel A. Schick
- Institute
of Molecular Toxicology and Pharmacology, Genetics and Cellular Engineering
Group, HelmholtzZentrum Muenchen, Ingolstaedter Landstr. 1, 85764 Neuherberg, Germany
- E-mail:
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Jayaraj RL, Beiram R, Azimullah S, Meeran MFN, Ojha SK, Adem A, Jalal FY. Lycopodium Attenuates Loss of Dopaminergic Neurons by Suppressing Oxidative Stress and Neuroinflammation in a Rat Model of Parkinson's Disease. Molecules 2019; 24:molecules24112182. [PMID: 31185705 PMCID: PMC6600474 DOI: 10.3390/molecules24112182] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 05/26/2019] [Accepted: 06/04/2019] [Indexed: 02/06/2023] Open
Abstract
Parkinson's disease, a chronic, age related neurodegenerative disorder, is characterized by a progressive loss of nigrostriatal dopaminergic neurons. Several studies have proven that the activation of glial cells, presence of alpha-synuclein aggregates, and oxidative stress, fuels neurodegeneration, and currently there is no definitive treatment for PD. In this study, a rotenone-induced rat model of PD was used to understand the neuroprotective potential of Lycopodium (Lyc), a commonly-used potent herbal medicine. Immunohistochemcial data showed that rotenone injections significantly increased the loss of dopaminergic neurons in the substantia nigra, and decreased the striatal expression of tyrosine hydroxylase. Further, rotenone administration activated microglia and astroglia, which in turn upregulated the expression of α-synuclein, pro-inflammatory, and oxidative stress factors, resulting in PD pathology. However, rotenone-injected rats that were orally treated with lycopodium (50 mg/kg) were protected against dopaminergic neuronal loss by diminishing the expression of matrix metalloproteinase-3 (MMP-3) and MMP-9, as well as reduced activation of microglia and astrocytes. This neuroprotective mechanism not only involves reduction in pro-inflammatory response and α-synuclein expression, but also synergistically enhanced antioxidant defense system by virtue of the drug's multimodal action. These findings suggest that Lyc has the potential to be further developed as a therapeutic candidate for PD.
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Affiliation(s)
- Richard L Jayaraj
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.
| | - Rami Beiram
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.
| | - Sheikh Azimullah
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.
| | - Mohamed Fizur Nagoor Meeran
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.
| | - Shreesh K Ojha
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.
| | - Abdu Adem
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.
| | - Fakhreya Yousuf Jalal
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.
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Zschiebsch K, Fischer C, Wilken‐Schmitz A, Geisslinger G, Channon K, Watschinger K, Tegeder I. Mast cell tetrahydrobiopterin contributes to itch in mice. J Cell Mol Med 2019; 23:985-1000. [PMID: 30450838 PMCID: PMC6349351 DOI: 10.1111/jcmm.13999] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 09/25/2018] [Accepted: 10/13/2018] [Indexed: 12/28/2022] Open
Abstract
GTP cyclohydrolase (GCH1) governs de novo synthesis of the enzyme cofactor, tetrahydrobiopterin (BH4), which is essential for biogenic amine production, bioactive lipid metabolism and redox coupling of nitric oxide synthases. Overproduction of BH4 via upregulation of GCH1 in sensory neurons is associated with nociceptive hypersensitivity in rodents, and neuron-specific GCH1 deletion normalizes nociception. The translational relevance is revealed by protective polymorphisms of GCH1 in humans, which are associated with a reduced chronic pain. Because myeloid cells constitute a major non-neuronal source of BH4 that may contribute to BH4-dependent phenotypes, we studied here the contribution of myeloid-derived BH4 to pain and itch in lysozyme M Cre-mediated GCH1 knockout (LysM-GCH1-/- ) and overexpressing mice (LysM-GCH1-HA). Unexpectedly, knockout or overexpression in myeloid cells had no effect on nociceptive behaviour, but LysM-driven GCH1 knockout reduced, and its overexpression increased the scratching response in Compound 48/80 and hydroxychloroquine-evoked itch models, which involve histamine and non-histamine dependent signalling pathways. Mechanistically, GCH1 overexpression increased BH4, nitric oxide and hydrogen peroxide, and these changes were associated with increased release of histamine and serotonin and degranulation of mast cells. LysM-driven GCH1 knockout had opposite effects, and pharmacologic inhibition of GCH1 provided even stronger itch suppression. Inversely, intradermal BH4 provoked scratching behaviour in vivo and BH4 evoked an influx of calcium in sensory neurons. Together, these loss- and gain-of-function experiments suggest that itch in mice is contributed by BH4 release plus BH4-driven mediator release from myeloid immune cells, which leads to activation of itch-responsive sensory neurons.
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Affiliation(s)
- Katja Zschiebsch
- Institute of Clinical PharmacologyGoethe‐University HospitalFrankfurtGermany
| | - Caroline Fischer
- Institute of Clinical PharmacologyGoethe‐University HospitalFrankfurtGermany
| | | | - Gerd Geisslinger
- Institute of Clinical PharmacologyGoethe‐University HospitalFrankfurtGermany
| | - Keith Channon
- Division of Cardiovascular MedicineUniversity of OxfordOxfordUK
| | - Katrin Watschinger
- Division of Biological ChemistryBiocenterMedical University of InnsbruckInnsbruckAustria
| | - Irmgard Tegeder
- Institute of Clinical PharmacologyGoethe‐University HospitalFrankfurtGermany
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Verma A, Leekha A, Kumar V, Moin I, Gurjar B. Modulation of oxidative stress by doxorubicin loaded chitosan nanoparticles. JOURNAL OF CANCER RESEARCH AND PRACTICE 2019. [DOI: 10.4103/jcrp.jcrp_18_18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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11
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Sipahl H, Bayram FEO, Palabiyik SS, Bayram D, Aydin A. Investigation of the Biocompatibility of Surgical Masks. Pteridines 2018. [DOI: 10.1515/pteridines-2018-0007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Abstract
According to the ISO10993-1 standard medical devices should be evaluated before marketing. Although there are studies that monitor the toxicity of several marketed medical devices, none of them describe the toxicity of masks that are widely used to avoid occupational exposure to biological hazard or toxic chemicals. The aim of this study was to evaluate the biocompatibility of eight purchased surgical masks of different brands, investigating their cytotoxicity and inflammation inducing capacity. Cytotoxicity was assessed via the MTT cell viability assay and inflammation was monitored by measuring nitrite, kynurenine and tryptophan levels. A preliminary study revealed that four samples were capable of killing L929 cells. Therefore the materials composing these masks were also evaluated separately. While the exposure to non-woven materials did not involve any changes in cell survival, exposing cells to elastic and sponge materials led to death in significant levels. Also, significant increases in nitrite levels with a decrease in tryptophan and kynurenine levels were obtained with cells treated with these materials, suggesting an inflammatory response that could be related to the observed cytotoxicity. Our studies revealed that the half of the randomly collected masks did not suit the biocompatibility criteria established by the ISO10993-1 standard, which is a quite unexpected result.
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Affiliation(s)
- Hande Sipahl
- Yeditepe University Faculty of Pharmacy, Department of Pharmaceutical Toxicology, 34755/ İstanbul , Turkey
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12
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Gamal M, Moawad J, Rashed L, Morcos MA, Sharawy N. Possible involvement of tetrahydrobiopterin in the disturbance of redox homeostasis in sepsis - Induced brain dysfunction. Brain Res 2018; 1685:19-28. [PMID: 29428597 DOI: 10.1016/j.brainres.2018.02.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Revised: 02/04/2018] [Accepted: 02/05/2018] [Indexed: 12/14/2022]
Abstract
BACKGROUND AND AIM Tetrahydrobiopterin (BH4) is an essential co-factor that regulates nitric oxide (NO) and reactive oxygen species (ROS) production by nitric oxide synthases (NOS). In this study, we evaluated the effects of sepsis on BH4 level and redox status in the brain by using the rat model of sepsis-induced by cecal ligation and puncture (CLP) and examined whether BH4 and/or acetyl-L-carnitine (ALC) could prevent the neuronal apoptosis and neurological changes induced by sepsis. MATERIAL AND METHOD Male albino rats were randomly and blindly divided into 8 groups: sham, sham + BH4, sham + ALC, sham +BH4+ ALC, CLP, CLP + BH4, CLP + ALC, and CLP+BH4+ ALC. We measured neurological indicators, brain levels of BH4, guanosine triphosphate cyclohydrolase (GTPCH), sepiapterin reductase (SR) and dihydropteridine reductase (DHPR) genes expression (Essential enzymes in BH4 biosynthesis and recycling pathways). We investigated also brain redox status and both endothelial and inducible NOS expressions. RESULTS Brain of septic rats demonstrated a reduced BH4 bioavailability, downregulation of BH4 synthetic enzymes, increased production of hydrogen peroxide and impaired antioxidant enzymes activities. Treatments with BH4 and/or ALC increased BH4 level, upregulated BH4 synthetic enzymes expressions, and attenuated oxidative-induced neuronal apoptosis. CONCLUSION Our results suggest that BH4 and/or ALC might protect the brain against oxidative stress induced neuronal apoptosis by restoring bioavailability of BH4 and upregulating of BH4 synthetic enzymes in the brain during sepsis.
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Affiliation(s)
- Maha Gamal
- Department of Physiology, Faculty of Medicine, Cairo University, Cairo, Egypt
| | - Jackline Moawad
- Department of Physiology, Faculty of Medicine, Cairo University, Cairo, Egypt
| | - Laila Rashed
- Department of Biochemistry, Faculty of Medicine, Cairo University, Cairo, Egypt
| | - Mary Attia Morcos
- Department of Histology, Faculty of Medicine, Cairo University, Cairo, Egypt
| | - Nivin Sharawy
- Department of Physiology, Faculty of Medicine, Cairo University, Cairo, Egypt; Cairo University Hospitals, Cairo, Egypt.
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13
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Lee JA, Son HJ, Kim JH, Park KD, Shin N, Kim HR, Kim EM, Kim DJ, Hwang O. A novel synthetic isothiocyanate ITC-57 displays antioxidant, anti-inflammatory, and neuroprotective properties in a mouse Parkinson’s disease model. Free Radic Res 2016; 50:1188-1199. [DOI: 10.1080/10715762.2016.1223293] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Ji Ae Lee
- Department of Biochemistry and Molecular Biology, Cell Dysfunction Research Center (CDRC), University of Ulsan College of Medicine, Seoul, Korea
| | - Hyo Jin Son
- Department of Biochemistry and Molecular Biology, Cell Dysfunction Research Center (CDRC), University of Ulsan College of Medicine, Seoul, Korea
| | - Ji Hyun Kim
- Department of Biochemistry and Molecular Biology, Cell Dysfunction Research Center (CDRC), University of Ulsan College of Medicine, Seoul, Korea
| | - Ki Duk Park
- Center for Neuro-Medicine, Brain Science Institute, Korea Institute of Science and Technology, Seoul, Korea
| | - Nari Shin
- Department of Biochemistry and Molecular Biology, Cell Dysfunction Research Center (CDRC), University of Ulsan College of Medicine, Seoul, Korea
| | - Hye Ri Kim
- Department of Biochemistry and Molecular Biology, Cell Dysfunction Research Center (CDRC), University of Ulsan College of Medicine, Seoul, Korea
| | - Eun Mee Kim
- Department of Emergency Medical Technology, Korea Nazarene University, Cheonan, South Korea
| | - Dong Jin Kim
- Center for Neuro-Medicine, Brain Science Institute, Korea Institute of Science and Technology, Seoul, Korea
| | - Onyou Hwang
- Department of Biochemistry and Molecular Biology, Cell Dysfunction Research Center (CDRC), University of Ulsan College of Medicine, Seoul, Korea
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Pannia E, Cho CE, Kubant R, Sánchez-Hernández D, Huot PSP, Harvey Anderson G. Role of maternal vitamins in programming health and chronic disease. Nutr Rev 2016; 74:166-80. [PMID: 26883881 DOI: 10.1093/nutrit/nuv103] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Vitamin consumption prior to and during pregnancy has increased as a result of proactive recommendations by health professionals, wide availability of vitamin supplements, and liberal food-fortification policies. Folic acid, alone or in combination with other B vitamins, is the most recommended vitamin consumed during pregnancy because deficiency of this vitamin leads to birth defects in the infant. Folic acid and other B vitamins are also integral components of biochemical processes that are essential to the development of regulatory systems that control the ability of the offspring to adapt to the external environment. Although few human studies have investigated the lasting effects of high vitamin intakes during pregnancy, animal models have shown that excess vitamin supplementation during gestation is associated with negative metabolic effects in both the mothers and their offspring. This research from animal models, combined with the recognition that epigenetic regulation of gene expression is plastic, provides evidence for further examination of these relationships in the later life of pregnant women and their children.
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Affiliation(s)
- Emanuela Pannia
- E. Pannia, C.E. Cho, R. Kubant, D. Sánchez-Hernández, P.S.P. Huot, and G.H. Anderson are with the Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada. G.H. Anderson is with the Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Clara E Cho
- E. Pannia, C.E. Cho, R. Kubant, D. Sánchez-Hernández, P.S.P. Huot, and G.H. Anderson are with the Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada. G.H. Anderson is with the Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Ruslan Kubant
- E. Pannia, C.E. Cho, R. Kubant, D. Sánchez-Hernández, P.S.P. Huot, and G.H. Anderson are with the Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada. G.H. Anderson is with the Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Diana Sánchez-Hernández
- E. Pannia, C.E. Cho, R. Kubant, D. Sánchez-Hernández, P.S.P. Huot, and G.H. Anderson are with the Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada. G.H. Anderson is with the Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Pedro S P Huot
- E. Pannia, C.E. Cho, R. Kubant, D. Sánchez-Hernández, P.S.P. Huot, and G.H. Anderson are with the Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada. G.H. Anderson is with the Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - G Harvey Anderson
- E. Pannia, C.E. Cho, R. Kubant, D. Sánchez-Hernández, P.S.P. Huot, and G.H. Anderson are with the Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada. G.H. Anderson is with the Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.
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15
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Lee JA, Son HJ, Park KD, Han SH, Shin N, Kim JH, Kim HR, Kim DJ, Hwang O. A Novel Compound ITC-3 Activates the Nrf2 Signaling and Provides Neuroprotection in Parkinson’s Disease Models. Neurotox Res 2015; 28:332-45. [DOI: 10.1007/s12640-015-9550-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Revised: 07/16/2015] [Accepted: 07/27/2015] [Indexed: 12/21/2022]
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16
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Induction of NQO1 and Neuroprotection by a Novel Compound KMS04014 in Parkinson’s Disease Models. J Mol Neurosci 2015; 56:263-72. [DOI: 10.1007/s12031-015-0516-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Accepted: 02/04/2015] [Indexed: 12/16/2022]
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Aryal B, Lee JK, Kim HR, Kim HG. Alteration of striatal tetrahydrobiopterin in iron-induced unilateral model of Parkinson's disease. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2014; 18:129-34. [PMID: 24757374 PMCID: PMC3994299 DOI: 10.4196/kjpp.2014.18.2.129] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Revised: 01/19/2014] [Accepted: 02/05/2014] [Indexed: 01/12/2023]
Abstract
It has been suggested that transition metal ions such as iron can produce an oxidative injuries to nigrostriatal dopaminergic neurons, like Parkinson's disease (PD) and subsequent compensative increase of tetrahydrobiopterin (BH4) during the disease progression induces the aggravation of dopaminergic neurodegeneration in striatum. It had been established that the direct administration of BH4 into neuron would induce the neuronal toxicity in vitro. To elucidate a role of BH4 in pathogenesis in the PD in vivo, we assessed the changes of dopamine (DA) and BH4 at striatum in unilateral intranigral iron infused PD rat model. The ipsistriatal DA and BH4 levels were significantly increased at 0.5 to 1 d and were continually depleting during 2 to 7 d after intranigral iron infusion. The turnover rate of BH4 was higher than that of DA in early phase. However, the expression level of GTP-cyclohydrolase I mRNA in striatum was steadily increased after iron administration. These results suggest that the accumulation of intranigral iron leads to generation of oxidative stress which damage to dopaminergic neurons and causes increased release of BH4 in the dopaminergic neuron. The degenerating dopaminergic neurons decrease the synthesis and release of both BH4 and DA in vivo that are relevance to the progression of PD. Based on these data, we propose that the increase of BH4 can deteriorate the disease progression in early phase of PD, and the inhibition of BH4 increase could be a strategy for PD treatment.
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Affiliation(s)
- Bijay Aryal
- Department of Pharmacology, College of Medicine, Dankook University, Cheonan 330-714, Korea
| | - Jin-Koo Lee
- Department of Pharmacology, College of Medicine, Dankook University, Cheonan 330-714, Korea. ; Translational Research Center, Institute of Bio-Science Technology, Dankook University, Cheonan 330-714, Korea
| | - Hak Rim Kim
- Department of Pharmacology, College of Medicine, Dankook University, Cheonan 330-714, Korea. ; Translational Research Center, Institute of Bio-Science Technology, Dankook University, Cheonan 330-714, Korea
| | - Hyung-Gun Kim
- Department of Pharmacology, College of Medicine, Dankook University, Cheonan 330-714, Korea. ; Translational Research Center, Institute of Bio-Science Technology, Dankook University, Cheonan 330-714, Korea
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Woo SY, Kim JH, Moon MK, Han SH, Yeon SK, Choi JW, Jang BK, Song HJ, Kang YG, Kim JW, Lee J, Kim DJ, Hwang O, Park KD. Discovery of vinyl sulfones as a novel class of neuroprotective agents toward Parkinson's disease therapy. J Med Chem 2014; 57:1473-87. [PMID: 24467268 DOI: 10.1021/jm401788m] [Citation(s) in RCA: 179] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Although the etiology of Parkinson's disease (PD) remains elusive, recent studies suggest that oxidative stress contributes to the cascade leading to dopaminergic (DAergic) neurodegeneration. The Nrf2 signaling is the main pathway responsible for cellular defense system against oxidative stress. Nrf2 is a transcription factor that regulates environmental stress response by inducing expression of antioxidant enzyme genes. We have synthesized novel vinyl sulfone derivatives. They exhibited a broad range of activities in inducing HO-1, whose gene expression is under the control of Nrf2. Among them, compound 12g was confirmed to activate Nrf2 and induce expression of the Nrf2-dependent antioxidant enzymes NQO1, GCLC, GLCM, and HO-1, at both mRNA and protein levels in DAergic neuronal cells. This was accompanied by protection of DAergic neurons in both in vitro and MPTP-induced in vivo models of PD. In addition, compound 12g effectively resulted in attenuation of the PD-associated behavioral deficits in the mouse model.
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Affiliation(s)
- Seo Yeon Woo
- Center for Neuro-Medicine, Brain Science Institute, and ‡Doping Control Center, Korea Institute of Science and Technology , Seoul, 136-791, Republic of Korea
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Yu L, Vásquez-Vivar J, Jiang R, Luo K, Derrick M, Tan S. Developmental susceptibility of neurons to transient tetrahydrobiopterin insufficiency and antenatal hypoxia-ischemia in fetal rabbits. Free Radic Biol Med 2014; 67:426-36. [PMID: 24316196 PMCID: PMC3945116 DOI: 10.1016/j.freeradbiomed.2013.11.026] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Revised: 11/22/2013] [Accepted: 11/25/2013] [Indexed: 01/13/2023]
Abstract
Tetrahydrobiopterin (BH4) is important for normal brain development as congenital BH4 deficiencies manifest movement disorders at various childhood ages. BH4 transitions from very low levels in fetal brains to higher "adult" levels postnatally, with the highest levels in the thalamus. Maternal supplementation with the BH4 precursor sepiapterin reduces postnatal motor deficits and perinatal deaths after 40-min fetal hypoxia-ischemia (HI) at 70% gestation, suggesting that brain BH4 is important in improving function after HI. We tested the hypothesis that the intrinsically low concentrations of BH4 made fetal neurons vulnerable to added insults. Brains were obtained from naïve fetal rabbits or after 40-min HI, at 70% (E22) and 92% gestation (E29). Neuronal cultures were prepared from basal ganglia, cortex, and thalamus, regions with different intrinsic levels of BH4. Cultures were grown with or without added BH4 for 48h. Cell survival and mitochondrial function were determined by flow cytometry. At E22, thalamic cells had the lowest survival rate in a BH4-free milieu, in both control and HI groups, whereas BH4 supplementation ex vivo increased neuronal survival only in HI cells. Neuronal survival was similar in all regions without BH4 at E29. BH4 supplementation increased cell survival and cells with intact mitochondrial membrane potential, from basal ganglia and cortex, but not thalamus. After E29 HI, however, the benefit of BH4 was limited to cortical neurons. We conclude that BH4 is important for fetal neuronal survival after HI especially in the premature thalamus. Supplementation of BH4 has a greater benefit at an earlier gestational age.
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Affiliation(s)
- Lei Yu
- Department of Pediatrics, NorthShore University HealthSystem, 2650 Ridge Avenue, Evanston, IL 60201
| | - Jeannette Vásquez-Vivar
- Department of Biophysics and Free Radical Research Center & Redox Biology Program, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee WI 53226
| | - Rugang Jiang
- Department of Pediatrics, NorthShore University HealthSystem, 2650 Ridge Avenue, Evanston, IL 60201
| | - Kehuan Luo
- Department of Pediatrics, NorthShore University HealthSystem, 2650 Ridge Avenue, Evanston, IL 60201
| | - Matthew Derrick
- Department of Pediatrics, NorthShore University HealthSystem, 2650 Ridge Avenue, Evanston, IL 60201
| | - Sidhartha Tan
- Department of Pediatrics, NorthShore University HealthSystem, 2650 Ridge Avenue, Evanston, IL 60201
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Miyajima M, Minoshima M, Tanaka M, Nishimura R, Hishioka N, Numata T, Hosokawa T, Kurasaki M, Saito T. Increase in tetrahydrobiopterin concentration with aging in the cerebral cortex of the senescence-accelerated mouse prone 10 strain caused by abnormal regulation of tetrahydrobiopterin biosynthesis. Biogerontology 2013; 14:491-501. [PMID: 23933678 DOI: 10.1007/s10522-013-9452-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 08/06/2013] [Indexed: 11/29/2022]
Abstract
6R-L-Erythro-5,6,7,8-tetrahydrobiopterin (BH4) is an essential cofactor for tyrosine hydroxylase (TH) activity and is a risk factor for cognitive decline and brain atrophy. Previous studies have shown that the decline in TH activity in the cerebral cortex of senescence-accelerated mouse prone 10 (SAMP10) mice is caused, at least in part, by a decrease in Fe, ferritin, and TH phosphorylation. We determined the concentrations of BH4 and the enzymes GTP cyclohydrolase-1,6-pyruvoyltetrahydropterin synthase and sepiapterin reductase (SPR) in the de novo pathway of BH4 biosynthesis. Dihydrofolate reductase (DHFR), which converts BH2 to BH4 in the salvage pathway of BH4 synthesis was also determined in the cerebral cortex of SAM mice at 3 and 12 months of age. The BH4 concentration was measured by HPLC, and the protein levels of enzymes involved in BH4 synthesis were measured by western blot analysis. At 12 months of age, BH4 concentration in the cerebral cortex of SAMP10 mice showed significantly higher values as compared to that of control mice. Further, the protein level of SPR in SAMP10 mice was significantly higher than that in SAMR1 mice at 3 and 12 months of age. In contrast to SPR, the protein level of DHFR in SAMP10 mice was significantly lower than that in SAMR1 mice. These results indicate that abnormal regulation of BH4 metabolism occurs in the cerebral cortex of SAMP10 where the dysfunction of the salvage pathway of BH4 synthesis may cause overproduction of BH4 through the de novo pathway, which is considered characteristic in the cerebral cortex of SAMP10 with aging. Therefore, there is a possibility that the excess amounts of BH4 lead to age-related brain dysfunction in the cerebral cortex of SAMP10.
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Affiliation(s)
- Miki Miyajima
- Graduate School of Health Sciences, Hokkaido University, Sapporo, 060-0812, Japan
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Son HJ, Lee JA, Shin N, Choi JH, Seo JW, Chi DY, Lee CS, Kim EM, Choe H, Hwang O. A novel compound PTIQ protects the nigral dopaminergic neurones in an animal model of Parkinson's disease induced by MPTP. Br J Pharmacol 2012; 165:2213-27. [PMID: 21951056 DOI: 10.1111/j.1476-5381.2011.01692.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND AND PURPOSE In Parkinson's disease, the dopaminergic neurones in the substantia nigra undergo degeneration. While the exact mechanism for the degeneration is not completely understood, neuronal apoptosis and neuroinflammation are thought to be key contributors. We have recently established that MMP-3 plays crucial roles in dopaminergic cell death and microglial activation. EXPERIMENTAL APPROACH We tested the effects of 7-hydroxy-6-methoxy-2-propionyl-1,2,3,4-tetrahydroisoquinoline (PTIQ) on expression of MMP-3 and inflammatory molecules and dopaminergic cell death in vitro and in an animal model of Parkinson's disease, and Parkinson's disease-related motor deficits. The pharmacokinetic profile of PTIQ was also evaluated. KEY RESULTS PTIQ effectively suppressed the production of MMP-3 induced in response to cellular stress in the dopaminergic CATH.a cell line and prevented the resulting cell death. In BV-2 microglial cells activated with lipopolysaccharide, PTIQ down-regulated expression of MMP-3 along with IL-1β, TNF-α and cyclooxygenase-2 and blocked nuclear translocation of NF-κB. In the mouse model of Parkinson's disease ,induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), PTIQ attenuated the associated motor deficits, prevented neurodegeneration and suppressed microglial activation in the substantia nigra. Pharmacokinetic analysis showed it was relatively stable against liver microsomal enzymes, did not inhibit the cytochrome p450 isozymes or the hERG ion channel, exhibited no cytotoxicity on liver cells or lethality when administered at 1000 mg kg(-1) and entered the brain rather rapidly yielding a 28% brain:plasma ratio after i.p. injection. CONCLUSIONS AND IMPLICATIONS These results suggest PTIQ has potential as a candidate drug for disease-modifying therapy for Parkinson's disease.
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Affiliation(s)
- Hyo Jin Son
- Department of Biochemistry, University of Ulsan College of Medicine, Seoul, Korea
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Matrix metalloproteinase-3 is activated by HtrA2/Omi in dopaminergic cells: relevance to Parkinson's disease. Neurochem Int 2012; 60:249-56. [PMID: 22265821 DOI: 10.1016/j.neuint.2012.01.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Revised: 12/19/2011] [Accepted: 01/03/2012] [Indexed: 12/21/2022]
Abstract
Dopaminergic neurons in the substantia nigra are particularly vulnerable, and their degeneration leads to Parkinson's disease. We have previously reported that matrix metalloproteinase-3 (MMP-3) activity is involved in dopaminergic neurodegeneration by multiple mechanisms and that this requires activation of MMP-3 from proMMP-3 by an intracellular serine protease. HtrA2/Omi is a mitochondrial serine protease that has been shown in non-dopaminergic cells to translocate into the cytosol where it triggers apoptosis. In the present study we sought to determine whether HtrA2/Omi might cause activation of MMP-3 in dopaminergic neuronal cells using CATH.a cell line. Mitochondrial stress induced by rotenone led to MMP-3 activation and HtrA2/Omi translocation into the cytosol. The MMP-3 activation involved HtrA2/Omi, because both pharmacological inhibition and siRNA-induced knockdown of HtrA2/Omi attenuated the activation induced by rotenone or MPP+. Overexpression of mature HtrA2/Omi, but not mutant HtrA2/Omi, resulted in MMP-3 activity increase and cell death. Addition of recombinant and catalytically active HtrA2/Omi to lysate of untreated cells led to activation of the endogenous MMP-3, and incubation of the HtrA2/Omi with recombinant proMMP-3 caused cleavage of proMMP-3 to a 48kD protein, corresponding to the active form, which was accompanied by an increase in MMP-3 activity. Taken together, the data indicate that HtrA2/Omi, which normally exists in the mitochondria, can cause MMP-3 activation in the cytosol under a cell stress condition, which can ultimately lead to demise of dopaminergic neuronal cells.
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Abstract
Matrix metalloproteinase-3 (MMP-3) is a member of the class of zinc-dependent proteases known to degrade the extracellular matrix. MMP-3 activity is regulated at three different levels: gene expression, proteolytic activation of the zymogen, and inhibition by the endogenous tissue inhibitors of metalloproteinase. A line of evidence indicates a role of MMP-3 in neurodegeneration. In neuronal cells, MMP-3 expression is increased in response to cell stress, and the cleaved, active MMP-3 participates in apoptotic signaling. In the extracellular space, MMP-3 triggers microglia to produce proinflammatory and cytotoxic molecules as well as MMP-3, which in turn contribute to neuronal damage. MMP-3 is increased in various experimental models of Parkinson's disease that are produced by selective toxins and by inflammagen, and the neuronal death is attenuated by various ways that inhibit MMP-3. α-Synuclein, whose gene mutations are associated with familial forms of Parkinson's disease, is proteolyzed by MMP-3. Contribution of MMP-3 toward the pathogenesis of Alzheimer's disease and other neurodegenerative diseases has also been suggested. Thus, modulation of MMP-3 expression and/or activity could be of therapeutic value for neurodegenerative diseases.
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Affiliation(s)
- Eun-Mee Kim
- Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine, Seoul, Korea
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p38(MAPK)/p53 signalling axis mediates neuronal apoptosis in response to tetrahydrobiopterin-induced oxidative stress and glucose uptake inhibition: implication for neurodegeneration. Biochem J 2010; 430:439-51. [PMID: 20590525 DOI: 10.1042/bj20100503] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BH4 (tetrahydrobiopterin) induces neuronal demise via production of ROS (reactive oxygen species). In the present study we investigated the mechanisms of its toxicity and the redox signalling events responsible for the apoptotic commitment in SH-SY5Y neuroblastoma cells and in mouse primary cortical neurons. We identified in p38(MAPK)/p53 a BH4-responsive pro-apoptotic signalling axis, as demonstrated by the recovery of neuronal viability achieved by gene silencing or pharmacological inhibition of both p38(MAPK) and p53. BH4-induced oxidative stress was characterized by a decrease in the GSH/GSSG ratio, an increase in protein carbonylation and DNA damage. BH4 toxicity and the redox-activated apoptotic pathway were counteracted by the H2O2-scavengers catalase and N-acetylcysteine and enhanced by the GSH neo-synthesis inhibitor BSO (buthionine sulfoximine). We also demonstrated that BH4 impairs glucose uptake and utilization, which was prevented by catalase administration. This effect contributes to the neuronal demise, exacerbating BH4-induced nuclear damage and the activation of the pro-apoptotic p38(MAPK)/p53 axis. Inhibition of glucose uptake was also observed upon treatment with 6-hydroxydopamine, another redox-cycling molecule, suggesting a common mechanism of action for auto-oxidizable neurotoxins.
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Yoon NS, Cho Y, Lee SY, Choi HJ, Hwang O. Inactivation of Aconitase by Tetrahydrobiopterin in DArgic Cells: Relevance to PD. Exp Neurobiol 2010; 19:23-9. [PMID: 22110338 PMCID: PMC3214796 DOI: 10.5607/en.2010.19.1.23] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2010] [Accepted: 04/26/2010] [Indexed: 11/19/2022] Open
Abstract
Oxidative damage is thought to be a major cause of the progression of dopamine (DA)rgic neurodegeneration as in Parkinson's disease. We have previously reported that tetrahydrobiopterin (BH4), an endogenous molecule required for DA synthesis, exerts oxidative stress to DA-producing cells and facilitates the production of DA quinone. It is known that aconitase, present in both mitochondrial and cytosolic forms, act as an reactive oxygen species (ROS) sensor, and that their inactivation leads to further generation of ROS. In the present study we investigated whether the BH4-associated vulnerability of DA cells might involve aconitase. In DArgic cell line CATH.a, BH4 treatment caused reduction of activity of both mitochondrial and cytosolic aconitases, and this appeared to be due to direct inactivation of the pre-existing enzyme molecules. Although most of the activity reduced by BH4 was increased upon reactivation reaction under a reducing condition, the restoration was not complete, suggesting that irreversible and covalent modification has occurred. The aconitase inactivation was exacerbated in the presence of DA and attenuated in the presence of tyrosine hydroxylase inhibitor a-methyl-p-tyrosine, suggesting the involvement of DA. The degree of inactivation increased when the cells were treated with the quinone reductase inhibitor dicoumarol and decreased in the presence of quinone reductase inducer sulforaphane. Taken together, BH4 appeared to lead to both reversible and irreversible inactivation of aconitase and that this is facilitated by the presence of DA and accumulation of DA quinone.
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Affiliation(s)
- Nam Soo Yoon
- Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine, Seoul 138-736, Korea
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Kim EM, Shin EJ, Choi JH, Son HJ, Park IS, Joh TH, Hwang O. Matrix metalloproteinase-3 is increased and participates in neuronal apoptotic signaling downstream of caspase-12 during endoplasmic reticulum stress. J Biol Chem 2010; 285:16444-52. [PMID: 20368330 PMCID: PMC2878010 DOI: 10.1074/jbc.m109.093799] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2009] [Revised: 03/07/2010] [Indexed: 12/22/2022] Open
Abstract
Although endoplasmic reticulum (ER) stress-induced apoptosis has been associated with pathogenesis of neurodegenerative diseases, the cellular components involved have not been well delineated. The present study shows that matrix metalloproteinase (MMP)-3 plays a role in the ER stress-induced apoptosis. ER stress induced by brefeldin A (BFA) or tunicamycin (TM) increases gene expression of MMP-3, selectively among various MMP subtypes, and the active form of MMP-3 (actMMP-3) in the brain-derived CATH.a cells. Pharmacological inhibition of enzyme activity, small interference RNA-mediated gene knockdown, and gene knock-out of MMP-3 all provide protection against ER stress. MMP-3 acts downstream of caspase-12, because both pharmacological inhibition and gene knockdown of caspase-12 attenuate the actMMP-3 increase, but inhibition and knock-out of MMP-3 do not alter caspase-12. Furthermore, independently of the increase in the protein level, the catalytic activity of MMP-3 enzyme can be increased via lowering of its endogenous inhibitor protein TIMP-1. Caspase-12 causes liberation of MMP-3 enzyme activity by degrading TIMP-1 that is already bound to actMMP-3. TIMP-1 is decreased in response to ER stress, and TIMP-1 overexpression leads to cell protection and a decrease in MMP-3 activity. Taken together, actMMP-3 protein level and catalytic activity are increased following caspase-12 activation during ER stress, and this in turn plays a role in the downstream apoptotic signaling in neuronal cells. MMP-3 and TIMP-1 may therefore serve as cellular targets for therapy against neurodegenerative diseases.
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Affiliation(s)
- Eun-Mee Kim
- From the Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine and
| | - Eun-Jung Shin
- From the Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine and
| | - Ji Hyun Choi
- From the Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine and
| | - Hyo Jin Son
- From the Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine and
| | - Il-Seon Park
- the Research Center for Proteineous Materials and Department of Bio-Materials Engineering, School of Medicine, Chosun University, Gwangju 501-759, Korea, and
| | - Tong H. Joh
- the Department of Neurology and Neuroscience, Weill Medical College of Cornell University, New York, New York 10021
| | - Onyou Hwang
- From the Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine and
- Center for Brain Research, Asan Institute for Life Science, Seoul 138-736, Korea
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Kim ST, Kim EM, Choi JH, Son HJ, Ji IJ, Joh TH, Chung SJ, Hwang O. Matrix metalloproteinase-3 contributes to vulnerability of the nigral dopaminergic neurons. Neurochem Int 2009; 56:161-7. [PMID: 19815046 DOI: 10.1016/j.neuint.2009.09.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2009] [Revised: 09/23/2009] [Accepted: 09/24/2009] [Indexed: 11/25/2022]
Abstract
Dopamine(DA)rgic neurons are particularly vulnerable due to the presence of oxidative stress-inducing molecules such as DA, tetrahydrobiopterin, iron and tyrosine hydroxylase (TH). We have recently observed that matrix metalloproteinase-3 (MMP-3) is involved in degeneration of DArgic neurons. In the present study, we sought to explore the role of MMP-3 in DArgic neurons not exposed to apparent stress conditions. In 8-week-old male mice deficient of MMP-3 gene (MMP-3 KO), the total number of DArgic neurons in the substantia nigra was considerably higher than wild type (WT). Primary cultured mesencephalic neurons from MMP-3 KO showed higher [(3)H]DA uptake capability compared to that of WT. The number of TH-immunopositive neurons and the length of average dendritic branch were also greater. This appeared to be selective for the DArgic system, because [(3)H]GABA uptake and calbindin D-28K and MAP-2 immunoreactivities were unaltered. On the other hand, no differences were noted in the levels of the striatal DA, DOPAC and BH4 and TH protein between the KO and WT. Interestingly, TH immunodensity per cell was lower in the DArgic neurons of MMP-3 KO both in primary culture and in vivo, suggesting the presence of a compensatory mechanism. These results further indicate a role of MMP-3 in the demise of DArgic neurons and suggest MMP-3 as a candidate cellular target for neuroprotective therapy.
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Affiliation(s)
- Sung Tae Kim
- Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine, Seoul, South Korea
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Cho Y, Son HJ, Kim EM, Choi JH, Kim ST, Ji IJ, Choi DH, Joh TH, Kim YS, Hwang O. Doxycycline is neuroprotective against nigral dopaminergic degeneration by a dual mechanism involving MMP-3. Neurotox Res 2009; 16:361-71. [PMID: 19582534 DOI: 10.1007/s12640-009-9078-1] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2008] [Revised: 05/15/2009] [Accepted: 06/18/2009] [Indexed: 01/10/2023]
Abstract
In Parkinson disease (PD), the dopaminergic (DAergic) neurons in the substantia nigra undergo degeneration. While the exact mechanism for the degeneration is still not completely understood, neuronal apoptosis and inflammation are thought to play roles. We have recently obtained evidence that matrix metalloproteinase (MMP)-3 plays a crucial role in the apoptotic signal in DAergic cells as well as activation of microglia. The present study tested whether doxycycline might modulate MMP-3 and provide neuroprotection of DAergic neurons. Doxycycline effectively suppressed the expression of MMP-3 induced in response to cellular stress in the DAergic CATH.a cells. This was accompanied by protection of CATH.a cells as well as primary cultured mesencephalic DAergic neurons via attenuation of apoptosis. The active form of MMP-3, released under the cell stress condition, was also decreased in the presence of doxycycline. In addition, doxycycline led to downregulation of MMP-3 in microglial BV-2 cells exposed to lipopolysaccharide (LPS). This was accompanied by suppression of production of nitric oxide and TNF-alpha, as well as gene expression of iNOS, TNF-alpha, IL-1beta, and COX-2. In vivo, doxycycline provided neuroprotection of the nigral DAergic neurons following MPTP treatment, as assessed by tyrosine hydroxylase immunocytochemistry and silver staining, and suppressed microglial activation and astrogliosis as assessed by Iba-1 and GFAP immunochemistry, respectively. Taken together, doxycycline showed neuroprotective effect on DAergic system both in vitro and in vivo and this appeared to derive from anti-apoptotic and anti-inflammatory mechanisms involving downregulation of MMP-3.
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Affiliation(s)
- Yuri Cho
- Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine, 388-1 Pungnap-dong, Songpa-ku, Seoul 138-736, Korea
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Nakashima A, Hayashi N, Kaneko YS, Mori K, Sabban EL, Nagatsu T, Ota A. Role of N-terminus of tyrosine hydroxylase in the biosynthesis of catecholamines. J Neural Transm (Vienna) 2009; 116:1355-62. [DOI: 10.1007/s00702-009-0227-8] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2008] [Accepted: 04/03/2009] [Indexed: 11/29/2022]
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Lim JH, Kim SS, Boo DH, No H, Kang BY, Kim EM, Hwang O, Choi HJ. Protective effect of bromocriptine against BH4-induced Cath.a cell death involving up-regulation of antioxidant enzymes. Neurosci Lett 2009; 451:185-9. [PMID: 19146917 DOI: 10.1016/j.neulet.2008.12.056] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2008] [Revised: 11/26/2008] [Accepted: 12/25/2008] [Indexed: 11/29/2022]
Abstract
Previously, we suggested that tetrahydrobiopterin (BH4), an obligatory cofactor for dopamine synthesis, as an intrinsic contributor to dopaminergic neuron vulnerability. The BH4 toxicity is observed in dopamine-producing cells, including Cath.a cells, but not in non-dopaminergic cells. Furthermore, the dopaminergic cell death induced by BH4 is apoptotic in nature and involves oxidative stress, similar to that observed in Parkinson's disease. Accordingly, various antioxidants have been found to protect dopaminergic cells from BH4. This study was undertaken to evaluate protective effects of the dopamine receptor agonist bromocriptine on BH4-induced Cath.a cell death, because bromocriptine has been reported to be an antioxidant with a neuroprotective activity. In the presence of bromocriptine, the increase in LDH activity and mitochondrial cytochrome c release induced by BH4 were significantly abolished. This cytoprotective effect was phosphatidylinositol 3-kinase (PI3K)/Akt pathway-dependent. In addition, bromocriptine was found to up-regulate the expressions of nuclear factor-E2-related factor-2 and antioxidant enzymes including NAD(P)H quinone oxidoreductase 1. Our findings show that bromocriptine stimulates antioxidant defense mechanisms in Cath.a cells and suggest a potential use of bromocriptine as a neuroprotectant.
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Affiliation(s)
- Ju Hee Lim
- Chonnam National University, Gwangju 500-757, South Korea
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31
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Chongthammakun V, Sanvarinda Y, Chongthammakun S. Reactive oxygen species production and MAPK activation are implicated in tetrahydrobiopterin-induced SH-SY5Y cell death. Neurosci Lett 2009; 449:178-82. [PMID: 19013215 DOI: 10.1016/j.neulet.2008.10.106] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2008] [Revised: 10/21/2008] [Accepted: 10/23/2008] [Indexed: 11/17/2022]
Abstract
Tetrahydrobiopterin (BH4), an obligatory cofactor for dopamine (DA) synthesis, has been shown to produce reactive oxygen species (ROS) upon its autoxidation and induce selective dopaminergic cell death in many in vivo and in vitro models of Parkinson's disease (PD). The precise molecular mechanisms underlying neuronal death upon BH4 exposure, however, have not yet been well elucidated. The present study aims to examine the intracellular ROS production and the signal transduction pathways underlying the toxic effects of BH4 on human dopaminergic SH-SY5Y cells. The results show that BH4 treatment at concentrations ranging from 50microM to 400microM induces neuronal death in a dose-dependent manner. In concomitant with the elevation of intracellular ROS formation, BH4-induced activation of MAPK, p38 and ERK1/2 in SH-SY5Y cells is attenuated by pretreatment with MAPK inhibitors, SB203580 or PD98059. These data indicate that MAPK activation and oxidative stress are involved in BH4-induced dopaminergic cell death, possibly through the autoxidation of BH4 and subsequent ROS production.
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Thöny B, Calvo AC, Scherer T, Svebak RM, Haavik J, Blau N, Martinez A. Tetrahydrobiopterin shows chaperone activity for tyrosine hydroxylase. J Neurochem 2008; 106:672-81. [PMID: 18419768 DOI: 10.1111/j.1471-4159.2008.05423.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Tyrosine hydroxylase (TH) is the rate-limiting enzyme in the synthesis of catecholamine neurotransmitters. Primary inherited defects in TH have been associated with l-DOPA responsive and non-responsive dystonia and infantile parkinsonism. In this study, we show that both the cofactor (6R)-l-erythro-5,6,7,8-tetrahydrobiopterin (BH(4)) and the feedback inhibitor and catecholamine product dopamine increase the kinetic stability of human TH isoform 1 in vitro. Activity measurements and synthesis of the enzyme by in vitro transcription-translation revealed a complex regulation by the cofactor including both enzyme inactivation and conformational stabilization. Oral BH(4) supplementation to mice increased TH activity and protein levels in brain extracts, while the Th-mRNA level was not affected. All together our results indicate that the molecular mechanisms for the stabilization are a primary folding-aid effect of BH(4) and a secondary effect by increased synthesis and binding of catecholamine ligands. Our results also establish that orally administered BH(4) crosses the blood-brain barrier and therapeutic regimes based on BH(4) supplementation should thus consider the effect on TH. Furthermore, BH(4) supplementation arises as a putative therapeutic agent in the treatment of brain disorders associated with TH misfolding, such as for the human TH isoform 1 mutation L205P.
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Affiliation(s)
- Beat Thöny
- Department of Pediatrics, University of Zürich, Zürich, Switzerland.
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Choi DH, Kim EM, Son HJ, Joh TH, Kim YS, Kim D, Flint Beal M, Hwang O. A novel intracellular role of matrix metalloproteinase-3 during apoptosis of dopaminergic cells. J Neurochem 2008; 106:405-15. [PMID: 18397366 DOI: 10.1111/j.1471-4159.2008.05399.x] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We have previously demonstrated that the active form of matrix metalloproteinase-3 (actMMP-3) is released from dopamine(DA)rgic neurons undergoing apoptosis. Herein, whether actMMP-3 might be generated intracellularly, and if so, whether it is involved in apoptosis of DArgic neurons itself was investigated in primary cultured DArgic neurons of wild-type, MMP-3 knockout animals, and CATH.a cells. During apoptosis, gene expression of MMP-3 is induced, specifically among the various classes of MMPs, generating the proform (55 kDa) which is subsequently cleaved to the catalytically active actMMP-3 (48 kDa) involving a serine protease. Intracellular actMMP-3 activity is directly linked to apoptotic signaling in DArgic cells: (i) Pharmacologic inhibition of enzymatic activity, repression of gene expression by siRNA, and gene deficiency all lead to protection; (ii) pharmacologic inhibition causes attenuation of DNA fragmentation and caspase 3 activation, the indices of apoptosis; and (iii) inhibition of the pro-apoptotic enzyme c-Jun N-terminal protein kinase leads to repression of MMP-3 induction. Under the cell stress condition, MMP-3 is released as actMMP-3 rather than the proform (proMMP-3), and catalytically active MMP-3 added to the medium does not cause cell death. Thus, actMMP-3 seems to have a novel intracellular role in apoptotic DArgic cells and this finding provides an insight into the pathogenesis of Parkinson's disease.
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Affiliation(s)
- Dong Hee Choi
- Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine, Seoul, Korea
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Seo JW, Srisook E, Son HJ, Hwang O, Cha YN, Chi DY. Syntheses of tetrahydroisoquinoline derivatives that inhibit NO production in activated BV-2 microglial cells. Eur J Med Chem 2008; 43:1160-70. [DOI: 10.1016/j.ejmech.2007.09.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2007] [Revised: 07/31/2007] [Accepted: 09/06/2007] [Indexed: 10/22/2022]
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35
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Chae SW, Bang YJ, Kim KM, Lee KY, Kang BY, Kim EM, Inoue H, Hwang O, Choi HJ. Role of cyclooxygenase-2 in tetrahydrobiopterin-induced dopamine oxidation. Biochem Biophys Res Commun 2007; 359:735-41. [PMID: 17560944 DOI: 10.1016/j.bbrc.2007.05.190] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2007] [Accepted: 05/26/2007] [Indexed: 01/09/2023]
Abstract
Dopamine is considered one of the main contributing factors in the induction of oxidative stress and selective dopaminergic neurodegeneration in Parkinson's disease. We have previously reported that tetrahydrobiopterin (BH4) leads to dopamine oxidation and renders dopamine-producing cells vulnerable. In the present study, we found that BH4 selectively upregulates cyclooxygenase-2 (COX-2) expression in dopaminergic cells. BH4 caused an induction of COX-2 mRNA, and a critical regulatory motif for BH4-induced transcriptional activation of COX-2 is CRE/AP-1. COX-2 can oxidize dopamine and cause oxidative stress, which is evidenced by the findings that significant increase in dopamine-chrome formation and protein carbonyl contents by BH4-induced COX-2 up-regulation, and the increases are abolished by COX-2 selective inhibitor meloxicam. Increased COX-2 promotes dopaminergic neurodegeneration in both SH-SY5Y cells and rat mesencephalic neurons. These data suggest that BH4-induced COX-2 expression is responsible for dopamine oxidation, leading to the preferential vulnerability of dopaminergic cells in Parkinson's disease.
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Affiliation(s)
- Sung-Wook Chae
- College of Pharmacy and Research Institute of Drug Development, Chonnam National University, Gwangju 500-757, South Korea
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36
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Han JM, Lee YJ, Lee SY, Kim EM, Moon Y, Kim HW, Hwang O. Protective effect of sulforaphane against dopaminergic cell death. J Pharmacol Exp Ther 2007; 321:249-56. [PMID: 17259450 DOI: 10.1124/jpet.106.110866] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Parkinson's disease (PD) is a progressive neurodegenerative disorder with a selective loss of dopaminergic neurons in the substantia nigra. Evidence suggests oxidation of dopamine (DA) to DA quinone and consequent oxidative stress as a major factor contributing to this vulnerability. We have previously observed that exposure to or induction of NAD(P)H:quinone reductase (QR1), the enzyme that catalyzes the reduction of quinone, effectively protects DA cells. Sulforaphane (SF) is a drug identified as a potent inducer of QR1 in various non-neuronal cells. In the present study, we show that SF protects against compounds known to induce DA quinone production (6-hydroxydopamine and tetrahydrobiopterin) in DAergic cell lines CATH.a and SK-N-BE(2)C as well as in mesencephalic DAergic neurons. SF leads to attenuation of the increase in protein-bound quinone in tetrahydrobiopterin-treated cells, but this does not occur in cells that have been depleted of DA, suggesting involvement of DA quinone. SF pretreatment prevents membrane damage, DNA fragmentation, and accumulation of reactive oxygen species. SF causes increases in mRNA levels and enzymatic activity of QR1 in a dose-dependent manner. Taken together, these results indicate that SF causes induction of QR1 gene expression, removal of intracellular DA quinone, and protection against toxicity in DAergic cells. Thus, this major isothiocyanate found in cruciferous vegetables may serve as a potential candidate for development of treatment and/or prevention of PD.
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Affiliation(s)
- Ji Man Han
- Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine, 388-1 Pungnap-dong, Songpa-ku, Seoul, 138-736, Korea
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Tobin JE, Cui J, Wilk JB, Latourelle JC, Laramie JM, McKee AC, Guttman M, Karamohamed S, DeStefano AL, Myers RH. Sepiapterin reductase expression is increased in Parkinson's disease brain tissue. Brain Res 2007; 1139:42-7. [PMID: 17270157 PMCID: PMC1868471 DOI: 10.1016/j.brainres.2007.01.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2006] [Revised: 12/21/2006] [Accepted: 01/02/2007] [Indexed: 11/18/2022]
Abstract
The PARK3 locus on chromosome 2p13 has shown linkage to both the development and age of onset of Parkinson's disease (PD). One candidate gene at this locus is sepiapterin reductase (SPR). Sepiapterin reductase catalyzes the final step in the biosynthetic pathway of tetrahydrobiopterin (BH(4)), an essential cofactor for aromatic amino acid hydrolases including tyrosine hydroxylase, the rate-limiting enzyme in dopamine synthesis. The expression of SPR was assayed using semiquantitative real-time RT-PCR in human post-mortem cerebellar tissue from neuropathologically confirmed PD cases and neurologically normal controls. The expression of other enzymes involved in BH(4) biosynthesis, including aldose reductase (AKR1B1), carbonyl reductase (CBR1 and CBR3), GTP-cyclohydrolase I (GCH1), and 6-pyruvoyltetrahydrobiopterin (PTS), was also examined. Single-nucleotide polymorphisms around the SPR gene that have been previously reported to show association to PD affection and onset age were genotyped in these samples. Expression of SPR showed a significant 4-fold increase in PD cases relative to controls, while the expression of AKR1B1 and PTS was significantly decreased in PD cases. No difference in expression was detected for CBR1, CBR3, and GCH1. Genetic variants did not show a significant effect on SPR expression, however, this is likely due to the low frequency of rare genotypes in the sample. While the association of SPR to PD is not strong enough to support that this is the PARK3 gene, this study further implicates a role for SPR in idiopathic PD.
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Affiliation(s)
- Jennifer E Tobin
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, MA 02118, USA.
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38
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Lee SY, Moon Y, Hee Choi D, Jin Choi H, Hwang O. Particular vulnerability of rat mesencephalic dopaminergic neurons to tetrahydrobiopterin: Relevance to Parkinson's disease. Neurobiol Dis 2007; 25:112-20. [PMID: 17049260 DOI: 10.1016/j.nbd.2006.08.024] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2006] [Revised: 08/21/2006] [Accepted: 08/30/2006] [Indexed: 10/24/2022] Open
Abstract
We determined whether tetrahydrobiopterin(BH4), an endogenous cofactor for dopamine(DA) synthesis, causes preferential damage to DArgic neurons among primary cultured rat mesencephalic neurons and whether the death mechanism has relevance to Parkinson's disease (PD). DArgic neurons were more vulnerable to BH4 than non-DArgic neurons, exhibiting sensitivity at lower concentrations, evident by morphological and neurotransmitter uptake studies. BH4-exposed DArgic neurons showed (1) increased TUNEL staining and activated caspase-3 immunoreactivity, indicative of apoptotic death; (2) mitochondrial membrane potential loss and increased cytosolic cytochrome c, suggesting mitochondrial dysfunction; (3) increased level of oxidized proteins and protection by antioxidants, indicative of oxidative stress; and (4) increased ubiquitin immunoreactivity, suggesting alteration of protein degradation pattern. Percent of cells positive for these parameters were much higher for DArgic neurons, demonstrating preferential vulnerability. Therefore, the DArgic neuronal damage induced by BH4, the molecule synthesized and readily upregulated in DArgic neurons and activated microglia, suggests physiological relevance to the pathogenesis of PD.
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Affiliation(s)
- So Yeon Lee
- Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine, 388-1 Pungnap-dong, Songpa-ku, Seoul, 138-736, Korea
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Tegeder I, Costigan M, Griffin RS, Abele A, Belfer I, Schmidt H, Ehnert C, Nejim J, Marian C, Scholz J, Wu T, Allchorne A, Diatchenko L, Binshtok AM, Goldman D, Adolph J, Sama S, Atlas SJ, Carlezon WA, Parsegian A, Lötsch J, Fillingim RB, Maixner W, Geisslinger G, Max MB, Woolf CJ. GTP cyclohydrolase and tetrahydrobiopterin regulate pain sensitivity and persistence. Nat Med 2006; 12:1269-77. [PMID: 17057711 DOI: 10.1038/nm1490] [Citation(s) in RCA: 399] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2006] [Accepted: 09/15/2006] [Indexed: 02/07/2023]
Abstract
We report that GTP cyclohydrolase (GCH1), the rate-limiting enzyme for tetrahydrobiopterin (BH4) synthesis, is a key modulator of peripheral neuropathic and inflammatory pain. BH4 is an essential cofactor for catecholamine, serotonin and nitric oxide production. After axonal injury, concentrations of BH4 rose in primary sensory neurons, owing to upregulation of GCH1. After peripheral inflammation, BH4 also increased in dorsal root ganglia (DRGs), owing to enhanced GCH1 enzyme activity. Inhibiting this de novo BH4 synthesis in rats attenuated neuropathic and inflammatory pain and prevented nerve injury-evoked excess nitric oxide production in the DRG, whereas administering BH4 intrathecally exacerbated pain. In humans, a haplotype of the GCH1 gene (population frequency 15.4%) was significantly associated with less pain following diskectomy for persistent radicular low back pain. Healthy individuals homozygous for this haplotype exhibited reduced experimental pain sensitivity, and forskolin-stimulated immortalized leukocytes from haplotype carriers upregulated GCH1 less than did controls. BH4 is therefore an intrinsic regulator of pain sensitivity and chronicity, and the GTP cyclohydrolase haplotype is a marker for these traits.
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Affiliation(s)
- Irmgard Tegeder
- Neural Plasticity Research Group, Department of Anesthesia and Critical Care, Massachusetts General Hospital & Harvard Medical School, 149 13th Street, Room 4309, Charlestown, Massachusetts 02129, USA
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40
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Abreu-González P, González-Hernández T, Afonso-Oramas D, Cruz-Muros I, Barroso-Chinea P, González MC. Tetrahydrobiopterin stimulates L-DOPA release from striatal tissue. Eur J Pharmacol 2006; 541:33-7. [PMID: 16750826 DOI: 10.1016/j.ejphar.2006.04.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2005] [Revised: 04/12/2006] [Accepted: 04/21/2006] [Indexed: 11/24/2022]
Abstract
In the present study we have analyzed the effect of tetrahydrobiopterin (BH4) essential cofactor for tyrosine hydroxylase and nitric oxide synthase, on the 3,4-dihydroxyphenylalanine (L-DOPA) release from in vitro incubated striatal tissue. dl-6-methyl-5,6,7,8 tetrahydropterine (6-MPH4)-stimulated L-DOPA release in a concentration-dependent manner in the range from 25 to 100 microM. At these concentrations 6-MPH4 did not have any effect on dopamine release. Presence of Nomega-Nitro-L-arginine methyl ester (L-NAME, 200 microM), a nitric oxide synthase inhibitor, but not of alpha-methyl-rho-tyrosine (alpha-MPT, 100 microM), a tyrosine hydroxylase inhibitor, blocked L-DOPA release induced by 6-MPH4 (200 microM). Also, the addition to the incubation medium of melatonin (MEL, 300 microM), which is a scavenger of NO and other free radicals, blocked the L-DOPA release induced by 6-MPH4 (200 microM) but this effect did not occur with the addition of the peroxynitrite scavenger uric acid (UA, 300 microM). Sodium nitroprusside (SNP, 100 muM), a NO generator and l-DOPA releaser as previously reported, potentiated the L-DOPA releasing effect of 6-MPH4 (200 microM) which was also blocked by melatonin. In summary 6-MPH4 stimulates L-DOPA release from striatal fragments incubated in vitro by a mechanism which involves NO or other free radicals derived from NO but not peroxynitrite.
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Affiliation(s)
- P Abreu-González
- Department of Physiology, University of La Laguna. 38320 Tenerife, Spain
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41
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Choi HJ, Lee SY, Cho Y, No H, Kim SW, Hwang O. Tetrahydrobiopterin causes mitochondrial dysfunction in dopaminergic cells: implications for Parkinson's disease. Neurochem Int 2006; 48:255-62. [PMID: 16343695 DOI: 10.1016/j.neuint.2005.10.011] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2005] [Revised: 10/13/2005] [Accepted: 10/20/2005] [Indexed: 12/21/2022]
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder associated with a selective loss of dopaminergic neurons in the substantia nigra. While the underlying cause of PD is not clearly understood, oxidative stress and mitochondrial dysfunction are thought to play a role. We have previously suggested tetrahydrobiopterin (BH4), an obligatory cofactor for the dopamine synthesis enzyme tyrosine hydroxylase and present selectively in monoaminergic neurons in the brain, as an endogenous molecule that contributes to the dopaminergic neurodegeneration. In the present study, we show that BH4 leads to inhibition of activities of complexes I and IV of the electron transport chain (ETC) and reduction of mitochondrial membrane potential. BH4 appears to be different from rotenone and MPP(+), the synthetic compounds used to generate Parkinson models, in its effect on complex IV. BH4 also induces the release of mitochondrial cytochrome c. Pretreatment with the sulfhydryl antioxidant N-acetylcysteine or the quinone reductase inducer dimethyl fumarate prevents the ETC inhibition and cytochrome c release following BH4 exposure, suggesting the involvement of quinone products. Together with our previous observation that BH4 leads to generation of oxidative stress and selective dopaminergic neurodegeneration both in vitro and in vivo via inducing apoptosis, the mitochondrial involvement in BH4 toxicity further suggests possible relevance of this endogenous molecule to pathogenesis of PD.
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Affiliation(s)
- Hyun Jin Choi
- Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine, 388-1 Pungnap-dong, Songpa-ku, Seoul 138-736, South Korea
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42
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Kim ST, Choi JH, Chang JW, Kim SW, Hwang O. Immobilization stress causes increases in tetrahydrobiopterin, dopamine, and neuromelanin and oxidative damage in the nigrostriatal system. J Neurochem 2005; 95:89-98. [PMID: 16181415 DOI: 10.1111/j.1471-4159.2005.03342.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Oxidative stress is believed to contribute to the pathophysiology of Parkinson's disease, in which nigrostriatal dopaminergic (DA) neurons undergo degeneration. Identification of endogenous molecules that contribute to generation of oxidative stress and vulnerability of these cells is critical in understanding the etiology of this disease. Exposure to tetrahydrobiopterin (BH4), the obligatory cofactor for DA synthesis, was observed previously to cause oxidative damage in DA cells. To demonstrate the physiological relevance of this observation, we investigated whether an overproduction of BH4 and DA might actually occur in vivo, and, if it did, whether this might lead to oxidative damage to the nigrostriatal system. Immobilization stress (IMO) elevated BH4 and DA and their synthesizing enzymes, tyrosine hydroxylase and GTP cyclohydrolase I. This was accompanied by elevation of lipid peroxidation and protein-bound quinone, and activities of antioxidant enzymes. These increases in the indices of oxidative stress appeared to be due to increased BH4 synthesis because they were abolished following administration of the BH4 synthesis inhibitor, 2,4-diamino-6-hydroxy-pyrimidine. IMO also caused accumulation of neuromelanin and degeneration of the nigrostriatal system. These results demonstrate that a severe stress can increase BH4 and DA and cause oxidative damages to the DA neurons in vivo, suggesting relevance to Parkinson's disease.
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Affiliation(s)
- Sung Tae Kim
- Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine, Seoul, Korea
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Seo JW, Srisook E, Son HJ, Hwang O, Cha YN, Chi DY. Syntheses of NAMDA derivatives inhibiting NO production in BV-2 cells stimulated with lipopolysaccharide. Bioorg Med Chem Lett 2005; 15:3369-73. [PMID: 15953725 DOI: 10.1016/j.bmcl.2005.05.033] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2005] [Revised: 05/04/2005] [Accepted: 05/10/2005] [Indexed: 10/25/2022]
Abstract
Sixteen derivatives of N-acetyl-3-O-methyldopamine (NAMDA), an inhibitor of BH4 synthesis, were designed and synthesized. The ability of these derivatives to inhibit NO and BH4 production by lipopolysaccharide-stimulated BV-2 microglial cells was determined. While NAMDA at 100 microM inhibited NO and BH4 production by only about 20%, its catecholamide 8, indole 23 derivative, 13, and N-acetyl tetrahydroisoquinoline 25 inhibited the NO production by >50% at the same concentration. In particular, 13 and 25 inhibited both NO and BH4 production to similar degrees, which suggested that these compounds might inhibit NO production by blocking BH4-dependent dimerization of the newly synthesized iNOS monomer.
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Affiliation(s)
- Jai Woong Seo
- Department of Chemistry, Inha University, 253 Yonghyundong Namgu, Inchon 402-751, Republic of Korea
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Chiarini A, Dal Pra I, Gottardo R, Bortolotti F, Whitfield JF, Armato U. BH(4) (tetrahydrobiopterin)-dependent activation, but not the expression, of inducible NOS (nitric oxide synthase)-2 in proinflammatory cytokine-stimulated, cultured normal human astrocytes is mediated by MEK-ERK kinases. J Cell Biochem 2005; 94:731-43. [PMID: 15565652 DOI: 10.1002/jcb.20334] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Nitric oxide (NO) from astrocytes is one of the signalers used by the brain's extensive glial-neuronal-vascular network, but its excessive production by pro-inflammatory cytokine-stimulated glial cells can be cytodestructive. Here, we show how three pro-inflammatory cytokines (IL-1beta, TNF-alpha, and IFN-gamma) together stimulated the activation, but not the prior expression, of NOS-2 protein via a mechanism involving MEK-ERKs protein kinases in astrocytes from adult human cerebral temporal cortex. The cytokines triggered a transient burst of p38 MAPK activity and the production of NOS-2 mRNA which were followed by bursts of MEK-ERK activities, synthesis of the NOS-2 co-factor tetrahydrobiopterin (BH(4)), a build-up of NOS-2 protein and from it active NOS-2 enzyme. Selectively inhibiting MEK1/MEK2, but not the earlier burst of p38 MAPK activity, with a brief exposure to U0126 between 24 and 24.5 h after adding the cytokine triad affected neither NOS-2 expression nor NOS-2 protein accumulation but stopped BH(4) synthesis and the assembly of the NOS-2 protein into active NOS-2 enzyme. The complete blockage of active NOS-2 production by the brief exposure to U0126 was bypassed by simply adding BH(4) to the culture medium. Therefore, this cytokine triad triggered two completely separable, tandem operating mechanisms in normal human astrocytes, the first being NOS-2 gene expression and accumulation of NOS-2 protein and the second being the synthesis of the BH(4) factor needed to dimerize the NOS-2 protein into active, NO-making NOS-2 enzyme.
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Affiliation(s)
- Anna Chiarini
- Department of Biomedical and Surgical Sciences, University of Verona Medical School, Verona I-37134, Italy
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Thoeni G, Werner ER, Werner-Felmayer G. Tetrahydropteridines suppress gene expression and induce apoptosis of activated RAW264.7 cells via formation of hydrogen peroxide. Free Radic Biol Med 2004; 37:375-85. [PMID: 15223071 DOI: 10.1016/j.freeradbiomed.2004.05.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2004] [Revised: 05/03/2004] [Accepted: 05/07/2004] [Indexed: 11/26/2022]
Abstract
Tetrahydrobiopterin, a redox-active cofactor, is essential for nitric oxide (NO) biosynthesis. Previous work showed that intracellular tetrahydrobiopterin levels modulate activity of nitric oxide synthases (NOSs). The 4-amino analog of tetrahydrobiopterin is an effective inhibitor of all three purified NOS isoforms that, in intact cells, preferentially targets the inducible isoenzyme. In vivo, 4-amino-tetrahydrobiopterin prolonged allograft survival and rescued rats from septic shock. Here we investigated the effects of tetrahydrobiopterin and its 4-amino analog on RAW264.7 murine macrophages activated with lipopolysaccharide. Surprisingly, both tetrahydropteridines inhibited NO formation. This was caused by downregulation of inducible NOS expression rather than by affecting enzyme activity. In addition, expression of tumor necrosis factor-alpha was impaired, and apoptosis, as characterized by quantifying DNA content and caspase-3 activation and being associated with the formation of a 33 kDa fragment of nuclear factor-kappaB p65, was induced. The effects of tetrahydropteridines were scavenged by catalase or glutathione but not by superoxide dismutase. Like tetrahydropteridines, hydrogen peroxide at concentrations comparable to those found in tetrahydropteridine-treated cultures affected gene expression and cell survival, whereas increasing intracellular tetrahydrobiopterin levels by sepiapterin did not. Thus, extracellular tetrahydropteridines suppress gene expression and induce apoptosis in RAW264.7 cells via hydrogen peroxide formed in the culture medium during autoxidation.
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Affiliation(s)
- Guntram Thoeni
- Institute of Medical Chemistry and Biochemistry, University of Innsbruck, A-6020 Innsbruck, Austria
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46
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Kim ST, Chang JW, Hong HN, Hwang O. Loss of striatal dopaminergic fibers after intraventricular injection of tetrahydrobiopterin in rat brain. Neurosci Lett 2004; 359:69-72. [PMID: 15050714 DOI: 10.1016/j.neulet.2004.02.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2003] [Revised: 02/03/2004] [Accepted: 02/08/2004] [Indexed: 11/21/2022]
Abstract
We have reported previously that tetrahydrobiopterin (BH4), an obligatory cofactor for dopamine synthesis, exerts preferential toxicity on dopamine producing cells. We report in the present study that BH4 injection into the lateral ventricle leads to degeneration of the dopaminergic terminals in the striatum, evidenced by a loss of tyrosine hydroxylase (TH) immunopositive fibers, a decreased amount of TH protein, and decreased dopamine content. Thus, the results of our study further provide evidence that BH4, the molecule endogenously present in the dopaminergic neurons, may participate in the nigrostriatal degeneration as in Parkinson's disease.
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Affiliation(s)
- Sung Tae Kim
- Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine, 388-1 Pungnap-dong, Songpa-ku, Seoul, South Korea
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47
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Choi HJ, Lee SY, Cho Y, Hwang O. JNK activation by tetrahydrobiopterin: implication for Parkinson's disease. J Neurosci Res 2004; 75:715-21. [PMID: 14991847 DOI: 10.1002/jnr.20012] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Parkinson's disease (PD) is a progressive neurologic disease associated with selective degeneration of dopaminergic neurons in the substantia nigra. Despite extensive studies to understand the underlying cause of dopaminergic degeneration, the pathologic factors leading to this neuronal loss in PD remain obscure. We have observed previously that tetrahydrobiopterin (BH4) exerts selective toxicity and oxidative stress on dopaminergic cells, suggesting that BH4 might participate endogenously in dopaminergic neurodegeneration in PD. We investigated signaling events leading to BH4 toxicity in dopaminergic CATH.a cells. We show that c-Jun N-terminal kinase (JNK), but not extracellular signal-regulated kinase (ERK) or p38 mitogen-activated protein kinase (MAPK), is phosphorylated significantly by BH4 exposure. BH4 also leads to c-Jun phosphorylation and an increase in c-Jun protein level. The JNK inhibitor SP600125 protects cells against BH4 toxicity and inhibits cytochrome c release and apoptotic nuclear condensation induced by BH4. These data indicate that activation of the JNK pathway is important in mediating BH4-induced dopaminergic cell death.
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Affiliation(s)
- Hyun Jin Choi
- Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine, Seoul, Korea
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Choi HJ, Kim SW, Im JH, Lee SG, Kim M, Hwang O. Utilization of exogenous tetrahydrobiopterin in nitric oxide synthesis in human neuroblastoma cell line. Neurosci Lett 2003; 352:89-92. [PMID: 14625030 DOI: 10.1016/j.neulet.2003.08.032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We and others have previously reported that neurons expressing neuronal nitric oxide synthase (nNOS) do not co-express GTP cyclohydrolase I, the enzyme that synthesize its cofactor tetrahydrobiopterin (BH4). BH4 is released from catecholaminergic cells and nNOS-expressing cells are located close to BH4-producing catecholaminergic nerve terminals. We show that BH4 is taken up into the nNOS-expressing human neuroblastoma cells TGW-I-nu in a linear, dose-dependent manner and elevates NO production. Direct exposure to BH4, dihydrobiopterin or biopterin, or coculture with catecholaminergic CATH.a cells increases NO production by TGW-I-nu. Thus, BH4-requiring nNOS cells may obtain BH4 from neighboring catecholaminergic cells or terminals and an intercellular crosstalk may exist between the two cells in vivo.
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Affiliation(s)
- Hyun Jin Choi
- Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine, 388-1 Pungnap-dong, Songpa-ku, Seoul 138-736, South Korea
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49
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Foster JA, Bezin L, Groc L, Christopherson PL, Levine RA. Kainic acid lesion-induced nigral neuronal death. J Chem Neuroanat 2003; 26:65-73. [PMID: 12954531 DOI: 10.1016/s0891-0618(03)00040-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Parkinson's disease (PD) is characterized by progressive death of dopamine (DA) neurons in the substantia nigra pars compacta. We report a rat model that exhibits progressive death of nigral neurons following unilateral injection of kainic acid in the striatum. In situ end-labeling revealed significant numbers of dying nigral neurons ipsilateral to the lesion during the first 3 weeks following injection. An indication of the gradual nature of death was that similar small numbers of cells were detected at each time point. These early morphological markers of neuronal death led to a significant reduction (20%) at 5 months of tyrosine hydroxylase-positive neurons and total number of neurons in the ipsilateral substantia nigra compared with the contralateral control. To examine the role of nigrostriatal DA metabolism in the observed nigral neuronal death, we manipulated DA metabolism during the initial 2 weeks following kainic acid lesion. Neurons in the ventral tier of the substantia nigra pars compacta were protected from death by treatment with 2,4-diamino-6-hydroxy-pyrimidine (DAHP), an inhibitor of GTP cyclohydrolase, the initial enzyme in the synthesis of the tyrosine hydroxylase co-substrate, tetrahydrobiopterin (BH(4)). Neurons in both the dorsal and ventral tier of substantia nigra pars compacta were protected from death by treatment with DAHP and L-DOPA. These experiments suggest that intrastriatal kainic acid lesion is an in vivo model of trophic support withdrawal. This experimental procedure is useful for studying mechanisms underlying protracted death of nigral DA neurons and may provide valuable mechanistic information relevant to understanding the etiology of PD.
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Affiliation(s)
- Jane A Foster
- William T. Gossett Neurology Laboratories, Henry Ford Health System, 1 Ford Place, 4D, Detroit, MI 48202, USA.
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50
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Choi HJ, Kim SW, Lee SY, Hwang O. Dopamine-dependent cytotoxicity of tetrahydrobiopterin: a possible mechanism for selective neurodegeneration in Parkinson's disease. J Neurochem 2003; 86:143-52. [PMID: 12807434 DOI: 10.1046/j.1471-4159.2003.01808.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Parkinson's disease is a neurodegenerative disorder associated with selective loss of dopaminergic neurons in the substantia nigra. While the underlying cause of this cell death is poorly understood, oxidative stress is thought to play a role. We have previously shown that tetrahydrobiopterin (BH4), an obligatory co-factor for tyrosine hydroxylase (TH), exerts selective toxicity on dopamine-producing cells and that this is prevented by antioxidants. This study shows that BH4-induced dopaminergic cell death is primarily mediated by dopamine, evidenced by findings that (i) BH4 toxicity is increased in proportion to cellular dopamine content; (ii) non-dopaminergic cells become susceptible to BH4 upon exposure to dopamine; and (iii) depletion of dopamine attenuates BH4 toxicity in dopamine-producing cells. BH4 causes lipid peroxidation, suggesting involvement of oxidative stress but the toxicity does not require enzymatic oxidation of dopamine. Instead, it seems to involve formation of quinone product(s) because (i) the cell death is attenuated by exposure to or induction of quinone reductase and (ii) BH4-treated cells show increased formation of protein-bound quinones, which is inhibited by thiol antioxidants. These data taken together suggest that the presence of both BH4 and dopamine is important in rendering dopaminergic cells vulnerable and that this involves formation of reactive dopamine quinone products.
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Affiliation(s)
- Hyun Jin Choi
- Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine, Seoul, Korea
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