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Vallucci M, Boutin JA, Janda E, Blandel F, Musgrove R, Di Monte D, Ferry G, Michel PP, Hirsch EC. The specific NQO2 inhibitor, S29434, only marginally improves the survival of dopamine neurons in MPTP-intoxicated mice. J Neural Transm (Vienna) 2024; 131:1-11. [PMID: 37851107 DOI: 10.1007/s00702-023-02709-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Accepted: 10/02/2023] [Indexed: 10/19/2023]
Abstract
Over the years, evidence has accumulated on a possible contributive role of the cytosolic quinone reductase NQO2 in models of dopamine neuron degeneration induced by parkinsonian toxin, but most of the data have been obtained in vitro. For this reason, we asked the question whether NQO2 is involved in the in vivo toxicity of MPTP, a neurotoxin classically used to model Parkinson disease-induced neurodegeneration. First, we show that NQO2 is expressed in mouse substantia nigra dopaminergic cell bodies and in human dopaminergic SH-SY5Y cells as well. A highly specific NQO2 inhibitor, S29434, was able to reduce MPTP-induced cell death in a co-culture system of SH-SY5Y cells with astrocytoma U373 cells but was inactive in SH-SY5Y monocultures. We found that S29434 only marginally prevents substantia nigra tyrosine hydroxylase+ cell loss after MPTP intoxication in vivo. The compound produced a slight increase of dopaminergic cell survival at day 7 and 21 following MPTP treatment, especially with 1.5 and 3 mg/kg dosage regimen. The rescue effect did not reach statistical significance (except for one experiment at day 7) and tended to decrease with the 4.5 mg/kg dose, at the latest time point. Despite the lack of robust protective activity of the inhibitor of NQO2 in the mouse MPTP model, we cannot rule out a possible role of the enzyme in parkinsonian degeneration, particularly because it is substantially expressed in dopaminergic neurons.
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Affiliation(s)
- Maeva Vallucci
- Sorbonne Université, Institut du Cerveau - Paris Brain Institute -ICM, INSERM, CNRS, Paris, France
| | - Jean A Boutin
- Laboratory of Neuroendocrine Endocrine and Germinal Differentiation and Communication (NorDiC), Univ Rouen Normandie, Inserm, NorDiC, UMR 1239, 76000, Rouen, France.
| | - Elzbieta Janda
- Department of Health Sciences, Campus Germaneto, Magna Graecia University, 88100, Catanzaro, Italy
| | - Florence Blandel
- Sorbonne Université, Institut du Cerveau - Paris Brain Institute -ICM, INSERM, CNRS, Paris, France
| | - Ruth Musgrove
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia
| | - Donato Di Monte
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Gilles Ferry
- Institut de R&D, Servier Paris-Saclay, 91190, Gif-Sur-Yvette, France
- Gilles Ferry Consulting, Les Issambres, France
| | - Patrick P Michel
- Sorbonne Université, Institut du Cerveau - Paris Brain Institute -ICM, INSERM, CNRS, Paris, France
| | - Etienne C Hirsch
- Sorbonne Université, Institut du Cerveau - Paris Brain Institute -ICM, INSERM, CNRS, Paris, France
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Niu X, Zhao R, Yan S, Pang Z, Li H, Yang X, Wang K. Chiral Materials: Progress, Applications, and Prospects. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2303059. [PMID: 37217989 DOI: 10.1002/smll.202303059] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 05/10/2023] [Indexed: 05/24/2023]
Abstract
Chirality is a universal phenomenon in molecular and biological systems, denoting an asymmetric configurational property where an object cannot be superimposed onto its mirror image by any kind of translation or rotation, which is ubiquitous on the scale from neutrinos to spiral galaxies. Chirality plays a very important role in the life system. Many biological molecules in the life body show chirality, such as the "codebook" of the earth's biological diversity-DNA, nucleic acid, etc. Intriguingly, living organisms hierarchically consist of homochiral building blocks, for example, l-amino acids and d-sugars with unknown reason. When molecules with chirality interact with these chiral factors, only one conformation favors the positive development of life, that is, the chiral host environment can only selectively interact with chiral molecules of one of the conformations. The differences in chiral interactions are often manifested by chiral recognition, mutual matching, and interactions with chiral molecules, which means that the stereoselectivity of chiral molecules can produce changes in pharmacodynamics and pathology. Here, the latest investigations are summarized including the construction and applications of chiral materials based on natural small molecules as chiral source, natural biomacromolecules as chiral sources, and the material synthesized by design as a chiral source.
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Affiliation(s)
- Xiaohui Niu
- College of Petrochemical Technology, Lanzhou University of Technology, Lanzhou, 730050, P. R. China
| | - Rui Zhao
- College of Petrochemical Technology, Lanzhou University of Technology, Lanzhou, 730050, P. R. China
| | - Simeng Yan
- College of Petrochemical Technology, Lanzhou University of Technology, Lanzhou, 730050, P. R. China
| | - Zengwei Pang
- College of Petrochemical Technology, Lanzhou University of Technology, Lanzhou, 730050, P. R. China
| | - Hongxia Li
- College of Petrochemical Technology, Lanzhou University of Technology, Lanzhou, 730050, P. R. China
| | - Xing Yang
- College of Polymer Science and Engineering, Sichuan University, Chengdu, 610065, P. R. China
| | - Kunjie Wang
- College of Petrochemical Technology, Lanzhou University of Technology, Lanzhou, 730050, P. R. China
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Milde S, van Tartwijk FW, Vilalta A, Hornik TC, Dundee JM, Puigdellívol M, Brown GC. Inflammatory neuronal loss in the substantia nigra induced by systemic lipopolysaccharide is prevented by knockout of the P2Y 6 receptor in mice. J Neuroinflammation 2021; 18:225. [PMID: 34635136 PMCID: PMC8504061 DOI: 10.1186/s12974-021-02280-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 09/22/2021] [Indexed: 12/17/2022] Open
Abstract
Inflammation may contribute to multiple brain pathologies. One cause of inflammation is lipopolysaccharide/endotoxin (LPS), the levels of which are elevated in blood and/or brain during bacterial infections, gut dysfunction and neurodegenerative diseases, such as Parkinson’s disease. How inflammation causes neuronal loss is unclear, but one potential mechanism is microglial phagocytosis of neurons, which is dependent on the microglial P2Y6 receptor. We investigated here whether the P2Y6 receptor was required for inflammatory neuronal loss. Intraperitoneal injection of LPS on 4 successive days resulted in specific loss of dopaminergic neurons (measured as cells staining with tyrosine hydroxylase or NeuN) in the substantia nigra of wild-type mice, but no neuronal loss in cortex or hippocampus. This supports the hypothesis that neuronal loss in Parkinson’s disease may be driven by peripheral LPS. By contrast, there was no LPS-induced neuronal loss in P2Y6 receptor knockout mice. In vitro, LPS-induced microglial phagocytosis of cells was prevented by inhibition of the P2Y6 receptor, and LPS-induced neuronal loss was reduced in mixed glial–neuronal cultures from P2Y6 receptor knockout mice. This supports the hypothesis that microglial phagocytosis contributes to inflammatory neuronal loss, and can be prevented by blocking the P2Y6 receptor, suggesting that P2Y6 receptor antagonists might be used to prevent inflammatory neuronal loss in Parkinson’s disease and other brain pathologies involving inflammatory neuronal loss.
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Affiliation(s)
- Stefan Milde
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | | | - Anna Vilalta
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Tamara C Hornik
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Jacob M Dundee
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Mar Puigdellívol
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Guy C Brown
- Department of Biochemistry, University of Cambridge, Cambridge, UK.
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TNFα increases tyrosine hydroxylase expression in human monocytes. NPJ Parkinsons Dis 2021; 7:62. [PMID: 34285243 PMCID: PMC8292430 DOI: 10.1038/s41531-021-00201-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 06/16/2021] [Indexed: 02/06/2023] Open
Abstract
Most, if not all, peripheral immune cells in humans and animals express tyrosine hydroxylase (TH), the rate limiting enzyme in catecholamine synthesis. Since TH is typically studied in the context of brain catecholamine signaling, little is known about changes in TH production and function in peripheral immune cells. This knowledge gap is due, in part, to the lack of an adequately sensitive assay to measure TH in immune cells expressing lower TH levels compared to other TH expressing cells. Here, we report the development of a highly sensitive and reproducible Bio-ELISA to quantify picogram levels of TH in multiple model systems. We have applied this assay to monocytes isolated from blood of persons with Parkinson's disease (PD) and to age-matched, healthy controls. Our study unexpectedly revealed that PD patients' monocytes express significantly higher levels of TH protein in peripheral monocytes relative to healthy controls. Tumor necrosis factor (TNFα), a pro-inflammatory cytokine, has also been shown to be increased in the brains and peripheral circulation in human PD, as well as in animal models of PD. Therefore, we investigated a possible connection between higher levels of TH protein and the known increase in circulating TNFα in PD. Monocytes isolated from healthy donors were treated with TNFα or with TNFα in the presence of an inhibitor. Tissue plasminogen activator (TPA) was used as a positive control. We observed that TNFα stimulation increased both the number of TH+ monocytes and the quantity of TH per monocyte, without increasing the total numbers of monocytes. These results revealed that TNFα could potentially modify monocytic TH production and serve a regulatory role in peripheral immune function. The development and application of a highly sensitive assay to quantify TH in both human and animal cells will provide a novel tool for further investigating possible PD immune regulatory pathways between brain and periphery.
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Yue D, Zeng C, Okyere SK, Chen Z, Hu Y. Glycine nano-selenium prevents brain oxidative stress and neurobehavioral abnormalities caused by MPTP in rats. J Trace Elem Med Biol 2021; 64:126680. [PMID: 33242795 DOI: 10.1016/j.jtemb.2020.126680] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 09/01/2020] [Accepted: 11/06/2020] [Indexed: 10/23/2022]
Abstract
BACKGROUND Parkinson's disease (PD) is a common degenerative disease of the central nervous system in the elderly. In recent years, the results of clinical and experimental studies have shown that oxidative stress is one of the important pathogenesis of PD. Selenium is one of the minor elements reported to possess antioxidant properties. Thus, the purpose of this study was to investigate the recovery effect of glycine nano-selenium on neurobehavioral abnormalities and oxidative stress caused by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in rat. MATERIALS AND METHODS SD male rats weighing 280-310 g were purchased from the Chengdu Dossy Experimental Animals Company, China. All rats were housed in a temperature-controlled room, with a 12 h light-dark cycles and had free access to food and water ad libitum. Rats were randomly divided into 4 groups with 8 animals in each group: the control group (normal saline), 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine group (MPTP), MPTP + 0.05 mg/kg glycine nano-selenium (MPTP + 0.05 Se), MPTP + 0.1 mg/kg glycine nano-selenium (MPTP + 0.1 Se). Behavioral assessment, clinical symptoms, Immunohistochemistry analysis of tyrosine hydroxylase (TH) and antioxidant activity were accessed to determine the protective effects glycine nano-selenium have on PD rats. RESULTS From the results, Rats showed a decrease in spontaneous motor behavior and an increase in pole test score. Also, the number of TH+ neurons were also significantly decreased (P < 0.05) after treated with MPTP for 7 days indicating that MPTP could successfully induce neurobehavioral abnormalities in rats. Furthermore, the lipid peroxide (MDA) levels of the PD model group were significantly increased and the antioxidant activities (SOD and GSH-PX) were significantly inhibited (P < 0.05) compared to the control group indicating the important role oxidative stress played in dopaminergic neuron death and neurobehavioral abnormalities in PD rats. Compared with the PD model group, glycine nano-selenium administration could significantly improve behavior and increase the number of TH+ neurons (P < 0.05) to protect against the loss of dopaminergic neurons. At the same time, glycine nano-selenium could decrease the MDA levels and increase the activities of SOD and GSH-PX significantly (P < 0.05). CONCLUSION In conclusion, PD rat model was successfully developed by intraperitoneal injection of MPTP and the intragastric administration of glycine nano-selenium reduced neurobehavioral abnormalities by decreasing oxidative stress in rat brain.
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Affiliation(s)
- Dong Yue
- Key Laboratory of Animal Disease and Human Health in Sichuan Province, Veterinary Medicine College of Sichuan Agricultural University, Chengdu 611130, China
| | - Chaorong Zeng
- Affiliated Sichuan Ba-Yi Rehabilitation Center of Chengdu University of TCM, Chengdu 611135, China.
| | - Samuel Kumi Okyere
- Key Laboratory of Animal Disease and Human Health in Sichuan Province, Veterinary Medicine College of Sichuan Agricultural University, Chengdu 611130, China
| | - Zhengli Chen
- Key Laboratory of Animal Disease and Human Health in Sichuan Province, Veterinary Medicine College of Sichuan Agricultural University, Chengdu 611130, China
| | - Yanchun Hu
- Key Laboratory of Animal Disease and Human Health in Sichuan Province, Veterinary Medicine College of Sichuan Agricultural University, Chengdu 611130, China.
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Autophagy status as a gateway for stress-induced catecholamine interplay in neurodegeneration. Neurosci Biobehav Rev 2021; 123:238-256. [PMID: 33497785 DOI: 10.1016/j.neubiorev.2021.01.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 01/08/2021] [Accepted: 01/09/2021] [Indexed: 12/13/2022]
Abstract
The catecholamine-containing brainstem nuclei locus coeruleus (LC) and ventral tegmental area (VTA) are critically involved in stress responses. Alterations of catecholamine systems during chronic stress may contribute to neurodegeneration, including cognitive decline. Stress-related catecholamine alterations, while contributing to anxiety and depression, might accelerate neuronal degeneration by increasing the formation of toxic dopamine and norepinephrine by-products. These, in turn, may impair proteostasis within a variety of cortical and subcortical areas. In particular, the molecular events governing neurotransmission, neuroplasticity, and proteostasis within LC and VTA affect a variety of brain areas. Therefore, we focus on alterations of autophagy machinery in these nuclei as a relevant trigger in this chain of events. In fact, these catecholamine-containing areas are mostly prone to autophagy-dependent neurodegeneration. Thus, we propose a dynamic hypothesis according to which stress-induced autophagy alterations within the LC-VTA network foster a cascade towards early neurodegeneration within these nuclei.
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Niaz K, Shah SZA, Khan F, Bule M. Ochratoxin A-induced genotoxic and epigenetic mechanisms lead to Alzheimer disease: its modulation with strategies. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:44673-44700. [PMID: 32424756 DOI: 10.1007/s11356-020-08991-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 04/22/2020] [Indexed: 06/11/2023]
Abstract
Ochratoxin A (OTA) is a naturally occurring mycotoxin mostly found in food items including grains and coffee beans. It induces DNA single-strand breaks and has been considered to be carcinogenic. It is recognized as a serious threat to reproductive health both in males and females. OTA is highly nephrotoxic and carcinogenic, and its potency changes evidently between species and sexes. There is a close association between OTA, mutagenicity, carcinogenicity, and genotoxicity, but the underlying mechanisms are not clear. Reports regarding genotoxic effects in relation to OTA which leads to the induction of DNA adduct formation, protein synthesis inhibition, perturbation of cellular energy production, initiation of oxidative stress, induction of apoptosis, influences on mitosis, induction of cell cycle arrest, and interference with cytokine pathways. All these mechanisms are associated with nephrotoxicity, hepatotoxicity, teratotoxicity, immunological toxicity, and neurotoxicity. OTA administration activates various mechanisms such as p38 MAPK, JNKs, and ERKs dysfunctions, BDNF disruption, TH overexpression, caspase-3 and 9 activation, and ERK-1/2 phosphorylation which ultimately lead to Alzheimer disease (AD) progression. The current review will focus on OTA in terms of recent discoveries in the field of molecular biology. The main aim is to investigate the underlying mechanisms of OTA in regard to genotoxicity and epigenetic modulations that lead to AD. Also, we will highlight the strategies for the purpose of attenuating the hazards posed by OTA exposure.
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Affiliation(s)
- Kamal Niaz
- Department of Pharmacology and Toxicology, Faculty of Bio-Sciences, Cholistan University of Veterinary and Animal Sciences, Bahawalpur, 63100, Pakistan.
| | - Syed Zahid Ali Shah
- Department of Pathology, Faculty of Veterinary Science, Cholistan University of Veterinary and Animal Sciences, Bahawalpur, 63100, Pakistan
| | - Fazlullah Khan
- The Institute of Pharmaceutical Sciences (TIPS), School of Pharmacy, International Campus, Tehran University of Medical Sciences (IC-TUMS), Tehran, 1417614411, Iran
- Department of Toxicology and Pharmacology, Faculty of Pharmacy, Tehran University of Medical Science, Tehran, 1417614411, Iran
| | - Mohammed Bule
- Department of Pharmacy, College of Medicine and Health Sciences, Ambo University, Ambo, Oromia, Ethiopia
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Gupta AK, Pokhriyal R, Das U, Khan MI, Ratna Kumar D, Gupta R, Chadda RK, Ramachandran R, Goyal V, Tripathi M, Hariprasad G. Evaluation of α-synuclein and apolipoprotein E as potential biomarkers in cerebrospinal fluid to monitor pharmacotherapeutic efficacy in dopamine dictated disease states of Parkinson's disease and schizophrenia. Neuropsychiatr Dis Treat 2019; 15:2073-2085. [PMID: 31410011 PMCID: PMC6650621 DOI: 10.2147/ndt.s205550] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 06/05/2019] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND AND OBJECTIVE Dopamine plays an important role in the disease pathology of Parkinson's disease and schizophrenia. These two neuropsychiatric disorders represent disease end points of the dopaminergic spectrum where Parkinson's disease represents dopamine deficit and schizophrenia represents dopamine hyperactivity in the mid-brain. Therefore, current treatment strategies aim to restore normal dopamine levels. However, during treatment patients develop adverse effects due to overshooting of physiological levels of dopamine leading to psychosis in Parkinson's disease, and extrapyramidal symptoms in schizophrenia. Absence of any laboratory tests hampers modulation of pharmacotherapy. Apolipoprotein E and α-synuclein have an important role in the neuropathology of these two diseases. The objective of this study was to evaluate cerebrospinal fluid (CSF) concentrations of apolipoprotein E and α-synuclein in patients with these two diseases so that they may serve as biomarkers to monitor therapy in Parkinson's disease and schizophrenia. METHODS Drug-naïve Parkinson's disease patients and Parkinson's disease patients treated with dopaminergic therapy, neurological controls, schizophrenic patients treated with antidopaminergic therapy, and drug-naïve schizophrenic patients were recruited for the study and CSF was collected. Enzyme-linked immunosorbent assays were carried out to estimate the concentrations of apolipoprotein E and α-synuclein. Pathway analysis was done to establish a possible role of these two proteins in various pathways in these two dopamine dictated diseases. RESULTS Apolipoprotein E and α-synuclein CSF concentrations have an inverse correlation along the entire dopaminergic clinical spectrum. Pathway analysis convincingly establishes a plausible hypothesis for their co-regulation in the pathogenesis of Parkinson's disease and schizophrenia. Each protein by itself or as a combination has encouraging sensitivity and specificity values of more than 55%. CONCLUSION The dynamic variation of these two proteins along the spectrum is ideal for them to be pursued as pharmacotherapeutic biomarkers in CSF to monitor pharmacological efficacy in Parkinson's disease and schizophrenia.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Vinay Goyal
- Department of Neurology, All India Institute of Medical Sciences, New Delhi110029, India
| | - Manjari Tripathi
- Department of Neurology, All India Institute of Medical Sciences, New Delhi110029, India
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Human tyrosine hydroxylase in Parkinson's disease and in related disorders. J Neural Transm (Vienna) 2018; 126:397-409. [PMID: 29995172 DOI: 10.1007/s00702-018-1903-3] [Citation(s) in RCA: 89] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 07/05/2018] [Indexed: 10/28/2022]
Abstract
Parkinson's disease (PD) is an aging-related movement disorder mainly caused by a deficiency of neurotransmitter dopamine (DA) in the striatum of the brain and is considered to be due to progressive degeneration of nigro-striatal DA neurons. Most PD is sporadic without family history (sPD), and there are only a few percent of cases of young-onset familial PD (fPD, PARKs) with the chromosomal locations and the genes identified. Tyrosine hydroxylase (TH), tetrahydrobiopterin (BH4)-dependent and iron-containing monooxygenase, catalyzes the conversion of L-tyrosine to L-3,4-dihydroxyphenylalanine (L-DOPA), which is the initial and rate-limiting step in the biosynthesis of catecholamines (DA, noradrenaline, and adrenaline). PD affects specifically TH-containing catecholamine neurons. The most marked neurodegeneration in patients with DA deficiency is observed in the nigro-striatal DA neurons, which contain abundant TH. Accordingly, TH has been speculated to play some important roles in the pathophysiology in PD. However, this decrease in TH is thought to be secondary due to neurodegeneration of DA neurons caused by some as yet unidentified genetic and environmental factors, and thus, TH deficiency may not play a direct role in PD. This manuscript provides an overview of the role of human TH in the pathophysiology of PD, covering the following aspects: (1) structures of the gene and protein of human TH in relation to PD; (2) similarity and dissimilarity between the phenotypes of aging-related sPD and those of young-onset fPD or DOPA-responsive dystonia due to DA deficiency in the striatum with decreased TH activity caused by mutations in either the TH gene or GTP cyclohydrolase I (GCH1) gene; and (3) genetic variants of the TH gene (polymorphisms, rare variants, and mutations) in PD, as discovered recently by advanced genome analysis.
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Collier TJ, Kanaan NM, Kordower JH. Aging and Parkinson's disease: Different sides of the same coin? Mov Disord 2017; 32:983-990. [PMID: 28520211 PMCID: PMC5844262 DOI: 10.1002/mds.27037] [Citation(s) in RCA: 159] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 04/10/2017] [Accepted: 04/13/2017] [Indexed: 02/07/2023] Open
Abstract
Despite abundant epidemiological evidence in support of aging as the primary risk factor for PD, biological correlates of a connection have been elusive. In this article, we address the following question: does aging represent biology accurately characterized as pre-PD? We present evidence from our work on midbrain dopamine neurons of aging nonhuman primates that demonstrates that markers of known correlates of dopamine neuron degeneration in PD, including impaired proteasome/lysosome function, oxidative/nitrative damage, and inflammation, all increase with advancing age and are exaggerated in the ventral tier substantia nigra dopamine neurons most vulnerable to degeneration in PD. Our findings support the view that aging-related changes in the dopamine system approach the biological threshold for parkinsonism, actively producing a vulnerable pre-parkinsonian state. © 2017 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Timothy J. Collier
- Department of Translational Science and Molecular Medicine, Michigan State University, Grand Rapids, Michigan, USA
- Mercy Health Hauenstein Neuroscience Center, Grand Rapids, Michigan, USA
| | - Nicholas M. Kanaan
- Department of Translational Science and Molecular Medicine, Michigan State University, Grand Rapids, Michigan, USA
- Mercy Health Hauenstein Neuroscience Center, Grand Rapids, Michigan, USA
| | - Jeffrey H. Kordower
- Department of Neurological Sciences, Rush University Medical Center, Chicago, Illinois, USA
- Center for Neurodegenerative Science, Van Andel Research Institute, Grand Rapids, Michigan, USA
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Bhat PV, Pandareesh, Khanum F, Tamatam A. Cytotoxic Effects of Ochratoxin A in Neuro-2a Cells: Role of Oxidative Stress Evidenced by N-acetylcysteine. Front Microbiol 2016; 7:1142. [PMID: 27531992 PMCID: PMC4969303 DOI: 10.3389/fmicb.2016.01142] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 07/07/2016] [Indexed: 01/08/2023] Open
Abstract
Ochratoxin-A (OTA), is toxic secondary metabolite and is found to be a source of vast range of toxic effects like hepatotoxicity, nephrotoxicity. However, the information available currently regarding neurotoxic effects exerted by OTA is scanty. Hence, the present study was aimed to evaluate the neurotoxic effects of OTA and the possible mechanisms of toxicity as well as the role of cytotoxic oxidative stress on neuronal (Neuro-2a) cell line was evaluated in vitro. Results of the MTT and LDH assay showed that, OTA induced dose-dependent cell death in Neuro-2a cells and EC50 value was determined as 500 nM. OTA induced high levels of reactive oxygen species (ROS) and elevated levels of malondialdehyde, also loss of mitochondrial membrane potential was observed in a dose depended manner. Effects of OTA on ROS induced chromosomal DNA damage was assessed by Comet assay and plasmid DNA damage assay in which increase in DNA damage was observed in Neuro-2a cells by increasing the OTA concentration. Further western blotting analysis of OTA treated Neuro-2a cells indicated elevated expression levels of c-Jun, JNK3 and cleaved caspase-3 leading to apoptotic cell death. Other hand realtime-Q-PCR analysis clearly indicates the suppressed expression of neuronal biomarker genes including AChE, BDNF, TH and NOS2. Further N-acetylcysteine (NAC) pretreatment to Neuro-2a cells followed by OTA treatment clearly evidenced that, the significant reversal of toxic effects exerted by OTA on Neuro-2a cells. In the present study, results illustrate that ROS a principle event in oxidative stress was elevated by OTA toxicity in Neuro-2a cells. However, further in vivo, animal studies are in need to conclude the present study reports and the use of NAC as a remedy for OTA induced neuronal stress.
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Affiliation(s)
- Pratiksha V Bhat
- Biochemistry and Nano Sciences Division, Defence Food Research Laboratory Mysore, India
| | - Pandareesh
- Biochemistry and Nano Sciences Division, Defence Food Research Laboratory Mysore, India
| | - Farhath Khanum
- Biochemistry and Nano Sciences Division, Defence Food Research Laboratory Mysore, India
| | - Anand Tamatam
- Biochemistry and Nano Sciences Division, Defence Food Research Laboratory Mysore, India
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Rodriguez M, Rodriguez-Sabate C, Morales I, Sanchez A, Sabate M. Parkinson's disease as a result of aging. Aging Cell 2015; 14:293-308. [PMID: 25677794 PMCID: PMC4406659 DOI: 10.1111/acel.12312] [Citation(s) in RCA: 136] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/16/2014] [Indexed: 12/15/2022] Open
Abstract
It is generally considered that Parkinson's disease is induced by specific agents that degenerate a clearly defined population of dopaminergic neurons. Data commented in this review suggest that this assumption is not as clear as is often thought and that aging may be critical for Parkinson's disease. Neurons degenerating in Parkinson's disease also degenerate in normal aging, and the different agents involved in the etiology of this illness are also involved in aging. Senescence is a wider phenomenon affecting cells all over the body, whereas Parkinson's disease seems to be restricted to certain brain centers and cell populations. However, reviewed data suggest that Parkinson's disease may be a local expression of aging on cell populations which, by their characteristics (high number of synaptic terminals and mitochondria, unmyelinated axons, etc.), are highly vulnerable to the agents promoting aging. The development of new knowledge about Parkinson's disease could be accelerated if the research on aging and Parkinson's disease were planned together, and the perspective provided by gerontology gains relevance in this field.
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Affiliation(s)
- Manuel Rodriguez
- Laboratory of Neurobiology and Experimental Neurology, Department of Physiology, Faculty of Medicine, University of La LagunaLa Laguna, Spain
- Center for Networked Biomedical Research in Neurodegenerative Diseases (CIBERNED)La Laguna, Spain
| | - Clara Rodriguez-Sabate
- Center for Networked Biomedical Research in Neurodegenerative Diseases (CIBERNED)La Laguna, Spain
| | - Ingrid Morales
- Laboratory of Neurobiology and Experimental Neurology, Department of Physiology, Faculty of Medicine, University of La LagunaLa Laguna, Spain
- Center for Networked Biomedical Research in Neurodegenerative Diseases (CIBERNED)La Laguna, Spain
| | - Alberto Sanchez
- Laboratory of Neurobiology and Experimental Neurology, Department of Physiology, Faculty of Medicine, University of La LagunaLa Laguna, Spain
| | - Magdalena Sabate
- Rehabilitation Service, Department of Pharmacology and Physical Medicine, Faculty of Medicine, University of La LagunaLa Laguna, Spain
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The Neuroprotective Mechanism of Low-Frequency rTMS on Nigral Dopaminergic Neurons of Parkinson's Disease Model Mice. PARKINSONS DISEASE 2015; 2015:564095. [PMID: 25883828 PMCID: PMC4390107 DOI: 10.1155/2015/564095] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Revised: 01/24/2015] [Accepted: 01/24/2015] [Indexed: 11/17/2022]
Abstract
Background. Parkinson's disease is a neurodegenerative disease in elder people, pathophysiologic basis of which is the severe deficiency of dopamine in the striatum. The purpose of the present study was to evaluate the neuroprotective effect of low-frequency rTMS on Parkinson's disease in model mice. Methods. The effects of low-frequency rTMS on the motor function, cortex excitability, neurochemistry, and neurohistopathology of MPTP-induced Parkinson's disease mice were investigated through behavioral detection, electrophysiologic technique, high performance liquid chromatography-electrochemical detection, immunohistochemical staining, and western blot. Results. Low-frequency rTMS could improve the motor coordination impairment of Parkinson's disease mice: the resting motor threshold significantly decreased in the Parkinson's disease mice; the degeneration of nigral dopaminergic neuron and the expression of tyrosine hydroxylase were significantly improved by low-frequency rTMS; moreover, the expressions of brain derived neurotrophic factor and glial cell line derived neurotrophic factor were also improved by low-frequency rTMS. Conclusions. Low-frequency rTMS had a neuroprotective effect on the nigral dopaminergic neuron which might be due to the improved expressions of brain derived neurotrophic factor and glial cell line-derived neurotrophic factor. The present study provided a theoretical basis for the application of low-frequency rTMS in the clinical treatment and recovery of Parkinson's disease.
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Rodriguez M, Morales I, Rodriguez-Sabate C, Sanchez A, Castro R, Brito JM, Sabate M. The degeneration and replacement of dopamine cells in Parkinson's disease: the role of aging. Front Neuroanat 2014; 8:80. [PMID: 25147507 PMCID: PMC4124707 DOI: 10.3389/fnana.2014.00080] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 07/22/2014] [Indexed: 01/06/2023] Open
Abstract
Available data show marked similarities for the degeneration of dopamine cells in Parkinson’s disease (PD) and aging. The etio-pathogenic agents involved are very similar in both cases, and include free radicals, different mitochondrial disturbances, alterations of the mitophagy and the ubiquitin-proteasome system. Proteins involved in PD such as α-synuclein, UCH-L1, PINK1 or DJ-1, are also involved in aging. The anomalous behavior of astrocytes, microglia and stem cells of the subventricular zone (SVZ) also changes similarly in aging brains and PD. Present data suggest that PD could be the expression of aging on a cell population with high vulnerability to aging. The future knowledge of mechanisms involved in aging could be critical for both understanding the etiology of PD and developing etiologic treatments to prevent the onset of this neurodegenerative illness and to control its progression.
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Affiliation(s)
- Manuel Rodriguez
- Laboratory of Neurobiology and Experimental Neurology, Department of Physiology, Faculty of Medicine, University of La Laguna La Laguna, Tenerife, Canary Islands, Spain ; Center for Networked Biomedical Research in Neurodegenerative Diseases (CIBERNED) Madrid, Spain
| | - Ingrid Morales
- Laboratory of Neurobiology and Experimental Neurology, Department of Physiology, Faculty of Medicine, University of La Laguna La Laguna, Tenerife, Canary Islands, Spain ; Center for Networked Biomedical Research in Neurodegenerative Diseases (CIBERNED) Madrid, Spain
| | - Clara Rodriguez-Sabate
- Center for Networked Biomedical Research in Neurodegenerative Diseases (CIBERNED) Madrid, Spain
| | - Alberto Sanchez
- Laboratory of Neurobiology and Experimental Neurology, Department of Physiology, Faculty of Medicine, University of La Laguna La Laguna, Tenerife, Canary Islands, Spain
| | - Rafael Castro
- Laboratory of Neurobiology and Experimental Neurology, Department of Physiology, Faculty of Medicine, University of La Laguna La Laguna, Tenerife, Canary Islands, Spain
| | - Jose Miguel Brito
- Laboratory of Neurobiology and Experimental Neurology, Department of Physiology, Faculty of Medicine, University of La Laguna La Laguna, Tenerife, Canary Islands, Spain
| | - Magdalena Sabate
- Rehabilitation Service, Department of Physical Medicine and Pharmacology, Faculty of Medicine, University of La Laguna La Laguna, Tenerife, Canary Islands, Spain
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Martorana A, Di Lorenzo F, Esposito Z, Lo Giudice T, Bernardi G, Caltagirone C, Koch G. Dopamine D2-agonist Rotigotine effects on cortical excitability and central cholinergic transmission in Alzheimer's disease patients. Neuropharmacology 2013; 64:108-13. [DOI: 10.1016/j.neuropharm.2012.07.015] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2012] [Revised: 07/06/2012] [Accepted: 07/08/2012] [Indexed: 11/27/2022]
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Szot P, Franklin A, Sikkema C, Wilkinson CW, Raskind MA. Sequential Loss of LC Noradrenergic and Dopaminergic Neurons Results in a Correlation of Dopaminergic Neuronal Number to Striatal Dopamine Concentration. Front Pharmacol 2012; 3:184. [PMID: 23129999 PMCID: PMC3487487 DOI: 10.3389/fphar.2012.00184] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Accepted: 10/02/2012] [Indexed: 11/17/2022] Open
Abstract
Noradrenergic neurons in the locus coeruleus (LC) are significantly reduced in Parkinson’s disease (PD) and the LC exhibits neuropathological changes early in the disease process. It has been suggested that a loss of LC neurons can enhance the susceptibility of dopaminergic neurons to damage. To determine if LC noradrenergic innervation protects dopaminergic neurons from damage, the dopaminergic neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) was administered to adult male C57Bl/6 mice 3 days after bilateral LC administration of 6-hydroxydopamine (6OHDA), a time when there is a significant reduction in LC neuronal number and innervation to forebrain regions. To assess if LC loss can affect dopaminergic loss four groups of animals were studied: control, 6OHDA, MPTP, and 6OHDA + MPTP; animals sacrificed 3 weeks after MPTP administration. The number of dopaminergic neurons in the substantia nigra (SN) and ventral tegmental area (VTA), and noradrenergic neurons in the LC were determined. Catecholamine levels in striatum were measured by high-pressure liquid chromatography. The loss of LC neurons did not affect the number of dopaminergic neurons in the SN and VTA compared to control; however, LC 6OHDA significantly reduced striatal dopamine (DA; 29% reduced) but not norepinephrine (NE) concentration. MPTP significantly reduced SN and VTA neuronal number and DA concentration in the striatum compared to control; however, there was not a correlation of striatal DA concentration with SN or VTA neuronal number. Administration of 6OHDA prior to MPTP did not enhance MPTP-induced damage despite an effect of LC loss on striatal DA concentration. However, the loss of LC neurons before MPTP resulted now in a correlation between SN and VTA neuronal number to striatal DA concentration. These results demonstrate that the loss of either LC or DA neurons can affect the function of each others systems, indicating the importance of both the noradrenergic and dopaminergic system in PD.
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Affiliation(s)
- Patricia Szot
- Mental Illness Research, Education and Clinical Center, Veterans Administration Puget Sound Health Care System Seattle, WA, USA ; Department of Psychiatry and Behavioral Sciences, University of Washington Seattle, WA, USA
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Bosier B, Muccioli GG, Mertens B, Sarre S, Michotte Y, Lambert DM, Hermans E. Differential modulations of striatal tyrosine hydroxylase and dopamine metabolism by cannabinoid agonists as evidence for functional selectivity in vivo. Neuropharmacology 2012; 62:2328-36. [PMID: 22365976 DOI: 10.1016/j.neuropharm.2012.02.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2011] [Revised: 01/27/2012] [Accepted: 02/06/2012] [Indexed: 01/07/2023]
Abstract
It is generally assumed that cannabinoids induce transient modulations of dopamine transmission through indirect regulation of its release. However, we previously described a direct cannabinoid-mediated control of tyrosine hydroxylase (TH) expression, in vitro. We herein report on the influence of cannabinoid agonists on the expression of this key enzyme in catecholamine synthesis as well as on the modification of dopamine content in adult rats. As expected for cannabinoid agonists, the exposure to either Δ(9)-THC, HU 210 or CP 55,940 induced both catalepsy and hypolocomotion. Supporting a possible long-lasting control on dopaminergic activity, we noticed a significant HU 210-mediated increase in TH expression in the striatum that was concomitant with an increase in striatal dopamine content. Surprisingly, while a similar trend was reported with Δ(9)-THC, CP 55,940 completely failed to modulate TH expression or dopamine content. Nevertheless, the access of CP 55,940 to brain structures was validated by determinations of drug concentrations in the tissue and by ex vivo binding experiments. Furthermore, confirming the central activity of CP 55,940, the analysis of dopamine metabolites revealed a reduction in striatal DOPAC concentrations. Consistent with the involvement of the CB(1) cannabinoid receptor in these different responses, both HU 210- and CP 55,940-mediated effects were prevented by SR 141716A. Therefore, the present data suggest that both HU 210 and CP 55,940 cause a delayed/persistent regulation of the dopamine neurotransmission system. Nevertheless, these commonly used cannabinoid agonists endowed with similar pharmacodynamic properties clearly triggered distinct biochemical responses highlighting the existence of functional selectivity in vivo.
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Affiliation(s)
- Barbara Bosier
- Neuropharmacology Group, Institute of Neuroscience, Université catholique de Louvain, 54.10, Av. Hippocrate 54, B-1200 Brussels, Belgium
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Clérin E, Wicker N, Mohand-Saïd S, Poch O, Sahel JA, Léveillard T. ℮-conome: an automated tissue counting platform of cone photoreceptors for rodent models of retinitis pigmentosa. BMC Ophthalmol 2011; 11:38. [PMID: 22185426 PMCID: PMC3271040 DOI: 10.1186/1471-2415-11-38] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Accepted: 12/20/2011] [Indexed: 11/24/2022] Open
Abstract
Background Retinitis pigmentosa is characterized by the sequential loss of rod and cone photoreceptors. The preservation of cones would prevent blindness due to their essential role in human vision. Rod-derived Cone Viability Factor is a thioredoxin-like protein that is secreted by rods and is involved in cone survival. To validate the activity of Rod-derived Cone Viability Factors (RdCVFs) as therapeutic agents for treating retinitis Pigmentosa, we have developed e-conome, an automated cell counting platform for retinal flat mounts of rodent models of cone degeneration. This automated quantification method allows for faster data analysis thereby accelerating translational research. Methods An inverted fluorescent microscope, motorized and coupled to a CCD camera records images of cones labeled with fluorescent peanut agglutinin lectin on flat-mounted retinas. In an average of 300 fields per retina, nine Z-planes at magnification X40 are acquired after two-stage autofocus individually for each field. The projection of the stack of 9 images is subject to a threshold, filtered to exclude aberrant images based on preset variables. The cones are identified by treating the resulting image using 13 variables empirically determined. The cone density is calculated over the 300 fields. Results The method was validated by comparison to the conventional stereological counting. The decrease in cone density in rd1 mouse was found to be equivalent to the decrease determined by stereological counting. We also studied the spatiotemporal pattern of the degeneration of cones in the rd1 mouse and show that while the reduction in cone density starts in the central part of the retina, cone degeneration progresses at the same speed over the whole retinal surface. We finally show that for mice with an inactivation of the Nucleoredoxin-like genes Nxnl1 or Nxnl2 encoding RdCVFs, the loss of cones is more pronounced in the ventral retina. Conclusion The automated platform ℮-conome used here for retinal disease is a tool that can broadly accelerate translational research for neurodegenerative diseases.
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Peripheral assessment of the genes AQP4, PBP and TH in patients with Parkinson's disease. Neurochem Res 2011; 37:512-5. [PMID: 22083667 DOI: 10.1007/s11064-011-0637-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2011] [Revised: 10/09/2011] [Accepted: 10/27/2011] [Indexed: 10/15/2022]
Abstract
Parkinson's disease (PD) typically appears in late middle-aged and in elderly persons progressing over a period of several years. The characteristic pathological features of PD patients include defective motor function and cognitive function affecting the quality of life of PD patients. Oxidative stress is considered to a play a central role along with various other factors in the pathogenesis of PD and the incidence and prevalence of the disease is incessantly increasing worldwide. The objective of the current study was to assess mRNA expressional changes of AQP4, TH and PBP in blood samples of control and patients with PD. The study included 30 healthy controls and 90 PD patients subjected to treatment through the entire period of the study. RNA isolation was carried out using blood samples of the subjects recruited in the study and used for RT-PCR analysis of AQP4, TH as well as PBP. The mRNA expressions of AQP4 and TH were found to be reduced whereas that of PBP was found to be elevated when compared with those of healthy control samples. The statistically analysed data were presented which could be helpful for appreciation of PD pathology reflecting in the blood samples of PD population.
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Collier TJ, Kanaan NM, Kordower JH. Ageing as a primary risk factor for Parkinson's disease: evidence from studies of non-human primates. Nat Rev Neurosci 2011; 12:359-66. [PMID: 21587290 DOI: 10.1038/nrn3039] [Citation(s) in RCA: 294] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Ageing is the greatest risk factor for the development of Parkinson's disease. However, the current dogma holds that cellular mechanisms that are associated with ageing of midbrain dopamine neurons and those that are related to dopamine neuron degeneration in Parkinson's disease are unrelated. We propose, based on evidence from studies of non-human primates, that normal ageing and the degeneration of dopamine neurons in Parkinson's disease are linked by the same cellular mechanisms and, therefore, that markers of cellular risk factors accumulate with age in a pattern that mimics the pattern of degeneration observed in Parkinson's disease. We contend that ageing induces a pre-parkinsonian state, and that the cellular mechanisms of dopamine neuron demise during normal ageing are accelerated or exaggerated in Parkinson's disease through a combination of genetic and environmental factors.
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Affiliation(s)
- Timothy J Collier
- Division of Translational Science and Molecular Medicine, Michigan State University, Grand Rapids, Michigan 49503, USA.
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Radcliffe PM, Sterling CR, Tank AW. Induction of tyrosine hydroxylase mRNA by nicotine in rat midbrain is inhibited by mifepristone. J Neurochem 2009; 109:1272-84. [PMID: 19476543 DOI: 10.1111/j.1471-4159.2009.06056.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Repeated nicotine administration induces tyrosine hydroxylase (TH) mRNA in rat midbrain. In this study we investigate the mechanisms responsible for this response using two models of midbrain dopamine neurons, rat ventral midbrain slice explant cultures and mouse MN9D cells. In both models nicotine stimulates TH gene transcription rate in a dose-dependent manner. However, this stimulation is short-lived, lasting for 1 h, but less than 3 h, and is not sufficient to induce TH mRNA or TH protein. Nicotine elevates circulating glucocorticoids, which induce TH expression in some model systems. We tested the hypothesis that the effect of nicotine on midbrain TH mRNA is mediated by the glucocorticoid receptor. When rats are administered the glucocorticoid receptor antagonist mifepristone, the induction of TH mRNA by nicotine in both substantia nigra and ventral tegmentum is inhibited. Furthermore, the glucocorticoid receptor agonist dexamethasone stimulates TH gene transcription for sustained periods of time in both midbrain slices and MN9D cells, leading to induction of TH mRNA and TH protein. Our results are consistent with the hypothesis that nicotine induces TH mRNA in midbrain by elevating glucocorticoids, which then act on glucocorticoid receptors in dopamine neurons leading to transcriptional activation of the TH gene.
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Affiliation(s)
- Pheona M Radcliffe
- Department of Pharmacology & Physiology, University of Rochester Medical Center, Rochester, New York 14642, USA
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Tank AW, Xu L, Chen X, Radcliffe P, Sterling CR. Post-transcriptional regulation of tyrosine hydroxylase expression in adrenal medulla and brain. Ann N Y Acad Sci 2009; 1148:238-48. [PMID: 19120116 DOI: 10.1196/annals.1410.054] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
It is well established that long-term stress leads to induction of tyrosine hydroxylase (TH) mRNA and TH protein in adrenal medulla and brain. This induction is usually associated with stimulation of the TH gene transcription rate. However, a number of studies have reported major discrepancies between the stress-induced changes in TH gene transcription, TH mRNA, and TH protein. These discrepancies suggest that post-transcriptional mechanisms also play an important role in regulating TH expression in response to stress and other stimuli. In this report, we summarize some of our findings and literature reports that demonstrate these discrepancies in adrenal medulla, locus ceruleus, and midbrain dopamine neurons. We then describe our recent work investigating the molecular mechanisms that mediate this post-transcriptional regulation in adrenal medulla and midbrain. Our results suggest that trans-acting factors binding to the polypyrimidine-rich region of the 3' untranslated region of TH mRNA play a role in these post-transcriptional mechanisms. A hypothetical cellular model describing this post-transcriptional regulation is proposed.
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Affiliation(s)
- A William Tank
- Department of Pharmacology and Physiology, University of Rochester Medical Center, Rochester, New York 14642, USA.
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Alladi PA, Mahadevan A, Yasha TC, Raju TR, Shankar SK, Muthane U. Absence of age-related changes in nigral dopaminergic neurons of Asian Indians: relevance to lower incidence of Parkinson's disease. Neuroscience 2008; 159:236-45. [PMID: 19135503 DOI: 10.1016/j.neuroscience.2008.11.051] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2008] [Revised: 11/15/2008] [Accepted: 11/18/2008] [Indexed: 12/14/2022]
Abstract
Age-related loss of melanized nigral neurons reported in the British Caucasians is not observed in Asian Indian, American and French adults. In the Americans, loss of dopaminergic phenotype occurs from midlife, without frank neurodegeneration. Here, we investigated whether nigral dopaminergic neurons in Asian Indians are lost with age or undergo morphological or biochemical dysfunction. Using unbiased stereology we estimated volume, number of melanized, borderline/non-melanized (n=34, 28 gestational weeks to 80 years) and tyrosine hydroxylase (TH)-Nurr1 co-labeled neurons (n=32, 28 gestational weeks to 80 years) in substantia nigra pars compacta. We quantified Nurr1 and TH proteins by immunoblotting (n=18, 28 gestational weeks to 69 years) and apoptotic neurons by terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) staining. Nuclear and soma size was estimated by morphometry. There was no age-related decline in volume, neuronal density, neuronal numbers and TH-Nurr1 co-labeled neurons. TH and Nurr1 protein expression remained stable. Lack of TUNEL-TH co-labeled cells confirmed absence of neuronal apoptosis. The neuronal size remained unaltered. Our findings of preserved nigral dopaminergic neurons suggest no age-related loss of nigral function in Asian Indians, unlike the Americans. This may explain the lower incidence of Parkinson's disease in Asian Indians.
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Affiliation(s)
- P A Alladi
- Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Bangalore 560029, India.
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Increased vesicular monoamine transporter binding during early abstinence in human methamphetamine users: Is VMAT2 a stable dopamine neuron biomarker? J Neurosci 2008; 28:9850-6. [PMID: 18815269 DOI: 10.1523/jneurosci.3008-08.2008] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Animal data indicate that methamphetamine can damage striatal dopamine terminals. Efforts to document dopamine neuron damage in living brain of methamphetamine users have focused on the binding of [(11)C]dihydrotetrabenazine (DTBZ), a vesicular monoamine transporter (VMAT2) positron emission tomography (PET) radioligand, as a stable dopamine neuron biomarker. Previous PET data report a slight decrease in striatal [(11)C]DTBZ binding in human methamphetamine users after prolonged (mean, 3 years) abstinence, suggesting that the reduction would likely be substantial in early abstinence. We measured striatal VMAT2 binding in 16 recently withdrawn (mean, 19 d; range, 1-90 d) methamphetamine users and in 14 healthy matched-control subjects during a PET scan with (+)[(11)C]DTBZ. Unexpectedly, striatal (+)[(11)C]DTBZ binding was increased in methamphetamine users relative to controls (+22%, caudate; +12%, putamen; +11%, ventral striatum). Increased (+)[(11)C]DTBZ binding in caudate was most marked in methamphetamine users abstinent for 1-3 d (+41%), relative to the 7-21 d (+15%) and >21 d (+9%) groups. Above-normal VMAT2 binding in some drug users suggests that any toxic effect of methamphetamine on dopamine neurons might be masked by an increased (+)[(11)C]DTBZ binding and that VMAT2 radioligand binding might not be, as is generally assumed, a "stable" index of dopamine neuron integrity in vivo. One potential explanation for increased (+)[(11)C]DTBZ binding is that VMAT2 binding is sensitive to changes in vesicular dopamine storage levels, presumably low in drug users. If correct, (+)[(11)C]DTBZ might be a useful imaging probe to correlate changes in brain dopamine stores and behavior in users of methamphetamine.
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Chen X, Xu L, Radcliffe P, Sun B, Tank AW. Activation of tyrosine hydroxylase mRNA translation by cAMP in midbrain dopaminergic neurons. Mol Pharmacol 2008; 73:1816-28. [PMID: 18349104 DOI: 10.1124/mol.107.043968] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
During prolonged stress or chronic treatment with neurotoxins, robust compensatory mechanisms occur that maintain sufficient levels of catecholamine neurotransmitters in terminal regions. One of these mechanisms is the up-regulation of tyrosine hydroxylase (TH), the enzyme that controls catecholamine biosynthesis. In neurons of the periphery and locus coeruleus, this up-regulation is associated with an initial induction of TH mRNA. In contrast, this induction either does not occur or it is nominal in mesencephalic dopamine neurons. The reasons for this lack of compensatory TH mRNA induction remain obscure, because so little is known about the regulation of TH expression in these neurons. In this study, we test whether activation of the cAMP signaling pathway regulates TH gene expression in two rodent models of midbrain dopamine neurons, ventral midbrain organotypic slice cultures and MN9D cells. Our results demonstrate that elevation of cAMP leads to induction of TH protein and TH activity in both model systems; however, TH mRNA levels are not up-regulated by cAMP. The induction of TH protein is the result of a novel post-transcriptional mechanism that activates TH mRNA translation. This translational activation is mediated by sequences within the 3' untranslated region (UTR) of TH mRNA. Our results support a model in which cAMP induces or activates trans-factors that interact with the TH mRNA 3'UTR to increase TH protein synthesis. An understanding of this novel regulatory mechanism may help to explain the control of TH gene expression and consequently dopamine biosynthesis in midbrain neurons under different physiological and pathological conditions.
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Affiliation(s)
- Xiqun Chen
- Department of Pharmacology and Physiology, Box 711, University of Rochester Medical Center, 601 Elmwood Ave., Rochester, NY 14642, USA
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Gründemann J, Schlaudraff F, Haeckel O, Liss B. Elevated alpha-synuclein mRNA levels in individual UV-laser-microdissected dopaminergic substantia nigra neurons in idiopathic Parkinson's disease. Nucleic Acids Res 2008; 36:e38. [PMID: 18332041 PMCID: PMC2367701 DOI: 10.1093/nar/gkn084] [Citation(s) in RCA: 130] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The presynaptic protein α-synuclein is involved in several neurodegenerative diseases, including Parkinson's disease (PD). In rare familial forms of PD, causal mutations (PARK1) as well as multiplications (PARK4) of the α-synuclein gene have been identified. In sporadic, idiopathic PD, abnormal accumulation and deposition of α-synuclein might also cause degeneration of dopaminergic midbrain neurons, the clinically most relevant neuronal population in PD. Thus, cell-specific quantification of α-synuclein expression-levels in dopaminergic neurons from idiopathic PD patients in comparison to controls would provide essential information about contributions of α-synuclein to the etiology of PD. However, a number of previous studies addressing this question at the tissue-level yielded varying results regarding α-synuclein expression. To increase specificity, we developed a cell-specific approach for mRNA quantification that also took into account the important issue of variable RNA integrities of the individual human postmortem brain samples. We demonstrate that PCR –amplicon size can confound quantitative gene-expression analysis, in particular of partly degraded RNA. By combining optimized UV-laser microdissection- and quantitative RT–PCR-techniques with suitable PCR assays, we detected significantly elevated α-synuclein mRNA levels in individual, surviving neuromelanin- and tyrosine hydroxylase-positive substantia nigra dopaminergic neurons from idiopathic PD brains compared to controls. These results strengthen the pathophysiologic role of transcriptional dysregulation of the α-synuclein gene in sporadic PD.
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Affiliation(s)
- Jan Gründemann
- Molecular Neurobiology, Department of Physiology, Philipps-University Marburg, Deutschhausstrasse 2, 35037 Marburg, Germany
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Chu Y, Kordower JH. Age-associated increases of alpha-synuclein in monkeys and humans are associated with nigrostriatal dopamine depletion: Is this the target for Parkinson's disease? Neurobiol Dis 2006; 25:134-49. [PMID: 17055279 DOI: 10.1016/j.nbd.2006.08.021] [Citation(s) in RCA: 306] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2006] [Revised: 08/31/2006] [Accepted: 08/31/2006] [Indexed: 01/12/2023] Open
Abstract
alpha-Synuclein is a synaptic protein that has been directly linked to both the etiology and pathogenesis of Parkinson's disease. We have previously shown that only nigral neurons in PD expressing alpha-synuclein inclusions display a loss dopaminergic phenotype. The present study tested the hypothesis that normal aging contributes to this effect. The relative abundance of alpha-synuclein protein within individual nigral neurons was quantified in eighteen normal humans between the age of 18 and 102 and twenty four rhesus monkeys between the age of 2 and 34. Optical densitometry revealed a robust age-related increase in alpha-synuclein protein within individual nigral neurons in both species. This effect was specific for nigral alpha-synuclein as no age-related changes were found in the ventral tegmental area nor were there changes in the nigra for non-pathogenic beta-synuclein. The age-related increases in nigral alpha-synuclein were non-aggregated and strongly associated with age-related decreases in tyrosine hydroxylase (TH), the rate limiting enzyme for dopamine production. In fact, only cells expressing alpha-synuclein displayed reductions in TH. We hypothesize that age-related increases in alpha-synuclein result in a subthreshold degeneration of nigrostriatal dopamine which, in PD, becomes symptomatic due to lysosomal failure resulting in protein misfolding and inclusion formation. We further hypothesize that preventing the age-related accumulation of non-aggregated alpha-synuclein might be a simple and potent therapeutic target for patients with PD.
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Affiliation(s)
- Yaping Chu
- Department of Neurological Sciences, Rush University Medical Center, 1735 West Harrison Street, Chicago, IL 60612, USA
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Millan MJ. Multi-target strategies for the improved treatment of depressive states: Conceptual foundations and neuronal substrates, drug discovery and therapeutic application. Pharmacol Ther 2006; 110:135-370. [PMID: 16522330 DOI: 10.1016/j.pharmthera.2005.11.006] [Citation(s) in RCA: 419] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2005] [Accepted: 11/28/2005] [Indexed: 12/20/2022]
Abstract
Major depression is a debilitating and recurrent disorder with a substantial lifetime risk and a high social cost. Depressed patients generally display co-morbid symptoms, and depression frequently accompanies other serious disorders. Currently available drugs display limited efficacy and a pronounced delay to onset of action, and all provoke distressing side effects. Cloning of the human genome has fuelled expectations that symptomatic treatment may soon become more rapid and effective, and that depressive states may ultimately be "prevented" or "cured". In pursuing these objectives, in particular for genome-derived, non-monoaminergic targets, "specificity" of drug actions is often emphasized. That is, priority is afforded to agents that interact exclusively with a single site hypothesized as critically involved in the pathogenesis and/or control of depression. Certain highly selective drugs may prove effective, and they remain indispensable in the experimental (and clinical) evaluation of the significance of novel mechanisms. However, by analogy to other multifactorial disorders, "multi-target" agents may be better adapted to the improved treatment of depressive states. Support for this contention is garnered from a broad palette of observations, ranging from mechanisms of action of adjunctive drug combinations and electroconvulsive therapy to "network theory" analysis of the etiology and management of depressive states. The review also outlines opportunities to be exploited, and challenges to be addressed, in the discovery and characterization of drugs recognizing multiple targets. Finally, a diversity of multi-target strategies is proposed for the more efficacious and rapid control of core and co-morbid symptoms of depression, together with improved tolerance relative to currently available agents.
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Affiliation(s)
- Mark J Millan
- Institut de Recherches Servier, Centre de Recherches de Croissy, Psychopharmacology Department, 125, Chemin de Ronde, 78290-Croissy/Seine, France.
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Chu Y, Le W, Kompoliti K, Jankovic J, Mufson EJ, Kordower JH. Nurr1 in Parkinson's disease and related disorders. J Comp Neurol 2006; 494:495-514. [PMID: 16320253 PMCID: PMC2564615 DOI: 10.1002/cne.20828] [Citation(s) in RCA: 153] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
In mammals, the transcription factor Nurr1 is expressed early in development and continues to be detectable throughout the organism's lifetime. Nurr1 is involved in the establishment and maintenance of the dopaminergic phenotype within specific central nervous system neuronal subpopulations including the nigrostriatal dopamine system. This protein is reduced over the course of normal aging, which is a major risk factor for Parkinson's disease (PD). However, whether Nurr1 expression is affected by PD has not been documented. The present study examined the role of Nurr1 in the maintenance of the dopaminergic phenotype within neurons in substantia nigra in PD compared with patients with diagnoses of progressive supranuclear palsy (PSP) or Alzheimer's disease (AD) or age-matched-matched controls. In PD, the optical density (OD) of Nurr1 immunofluorescence was significantly decreased in nigral neurons containing alpha-synuclein-immunoreactive inclusions. Similarly, the OD of Nurr1 immunofluorescence intensity in the nigra of AD cases was decreased in neurons with neurofibrillary tangles (NFTs). In contrast to PD and AD, the OD of Nurr1 immunofluorescence intensity was severely decreased in the neurons with or without NFTs in PSP cases. Decline of Nurr1-ir neuronal number and OD was observed within substantia nigra (SN) neurons in PD but not within hippocampal neurons. The decline in Nurr1-ir expression was correlated with loss of tyrosine hydroxylase immunofluorescence across the four groups. These data demonstrate that Nurr1 deficiency in dopaminergic neurons is associated with the intracellular pathology in both synucleinopathies and tauopathies.
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Affiliation(s)
- Yaping Chu
- Department of Neurological Science, Rush University Medical Center, Chicago, IL 60612
| | - Weidong Le
- Department of Neurology, Baylor College of Medicine, Houston, TX 77030
| | - Katie Kompoliti
- Department of Neurological Science, Rush University Medical Center, Chicago, IL 60612
| | - Joseph Jankovic
- Department of Neurology, Baylor College of Medicine, Houston, TX 77030
| | - Elliott J. Mufson
- Department of Neurological Science, Rush University Medical Center, Chicago, IL 60612
| | - Jeffrey H. Kordower
- Department of Neurological Science, Rush University Medical Center, Chicago, IL 60612
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Vinit S, Boulenguez P, Efthimiadi L, Stamegna JC, Gauthier P, Kastner A. Axotomized bulbospinal neurons express c-Jun after cervical spinal cord injury. Neuroreport 2005; 16:1535-9. [PMID: 16148740 DOI: 10.1097/01.wnr.0000179075.32035.0f] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
In several central nervous system neuronal populations, axotomy triggers the upregulation of regeneration-associated genes such as c-Jun, which determines neurons ability to regenerate axon in a growth-permissive environment. We analyzed the expression of c-Jun in rat ventral medullary neurons after cervical hemisection in order to investigate their intrinsic regenerative potential. Maximal expression of c-Jun was observed 7 days after injury mainly in axotomized medullary neurons located in the gigantocellularis nucleus, the raphe nucleus and, although less intensively, in the rostral ventral respiratory group. This suggests that after high cervical injury, a large number of medullary neurons projecting to the spinal cord become competent for axonal regeneration, although this regenerating potential may not be equivalent between the various neuronal populations.
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Affiliation(s)
- Stéphane Vinit
- Laboratoire de Physiologie Neurovégétative, Université Paul Cézanne Aix-Marseille III, Marseille, France.
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31
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Boyd LA, Winstein CJ. Providing explicit information disrupts implicit motor learning after basal ganglia stroke. Learn Mem 2004; 11:388-96. [PMID: 15286181 PMCID: PMC498316 DOI: 10.1101/lm.80104] [Citation(s) in RCA: 110] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2004] [Accepted: 06/09/2004] [Indexed: 11/24/2022]
Abstract
Despite their purported neuroanatomic and functional isolation, empirical evidence suggests that sometimes conscious explicit processes can influence implicit motor skill learning. Our goal was to determine if the provision of explicit information affected implicit motor-sequence learning after damage to the basal ganglia. Individuals with stroke affecting the basal ganglia (BG) and healthy controls (HC) practiced a continuous implicit motor-sequencing task; half were provided with explicit information (EI) and half were not (No-EI). The focus of brain damage for both BG groups was in the putamen. All of the EI participants were at least explicitly aware of the repeating sequence. Across three days of practice, explicit information had a differential effect on the groups. Explicit information disrupted acquisition performance in participants with basal ganglia stroke but not healthy controls. By retention (day 4), a dissociation was apparent--explicit information hindered implicit learning in participants with basal ganglia lesions but aided healthy controls. It appears that after basal ganglia stroke explicit information is less helpful in the development of the motor plan than is discovering a motor solution using the implicit system alone. This may be due to the increased demand placed on working memory by explicit information. Thus, basal ganglia integrity may be a crucial factor in determining the efficacy of explicit information for implicit motor-sequence learning.
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Affiliation(s)
- Lara A Boyd
- Department of Physical Therapy and Rehabilitation Sciences, Department of Neurology, University of Kansas Medical Center, Kansas City, Kansas 66160, USA.
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32
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Jakowec MW, Nixon K, Hogg E, McNeill T, Petzinger GM. Tyrosine hydroxylase and dopamine transporter expression following 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced neurodegeneration of the mouse nigrostriatal pathway. J Neurosci Res 2004; 76:539-50. [PMID: 15114626 DOI: 10.1002/jnr.20114] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Administration of the neurotoxicant 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) to C57BL/6 mice targets nigrostriatal dopaminergic neurons, leading to cell death and the depletion of striatal dopamine. After MPTP lesioning in young adult mice, surviving nigrostriatal dopaminergic neurons display robust and reproducible return of striatal dopamine weeks to months after injury. Thus, the mouse provides an excellent model with which to investigate the mechanisms underlying neuroplasticity of the nigrostriatal system following neurotoxic injury. The purpose of this study was to analyze proteins and mRNA transcripts of genes involved in dopamine biosynthesis (tyrosine hydroxylase; TH) and uptake (dopamine transporter; DAT) with regard to time course (7-90 days) after MPTP lesioning. Molecular analysis using immunohistochemistry and Western immunoblotting techniques demonstrated an increase in striatal TH by 30-60 days postlesioning that returned to near-control (prelesioned) levels by 60-90 days. In situ hybridization histochemistry indicated that this increase in TH protein might be due in part to increased TH mRNA expression in surviving nigrostriatal dopaminergic neurons. Analysis of TH protein at 7, 30, 60, and 90 days postlesioning with two-dimensional polyacrylamide gel electrophoresis in conjunction with Western immunoblotting revealed altered TH protein isoforms migrating at isoelectric points different from those of the native isoform. In contrast to TH protein, which returned to prelesioned levels by 60 days, DAT protein analysis showed that increased expression of striatal DAT protein did not return to near-prelesion levels until 90 days postlesioning. These results suggest that TH and DAT may differ in their time course of expression in surviving dopaminergic neurons and may play a role in mediating the return of striatal dopamine.
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Affiliation(s)
- Michael W Jakowec
- Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, California 90033, USA.
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33
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Volles MJ, Lansbury PT. Zeroing in on the pathogenic form of alpha-synuclein and its mechanism of neurotoxicity in Parkinson's disease. Biochemistry 2003; 42:7871-8. [PMID: 12834338 DOI: 10.1021/bi030086j] [Citation(s) in RCA: 327] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Parkinson's disease (PD) is linked to mutations in the protein alpha-synuclein, which can exist in vitro in several aggregation states, including a natively unfolded monomer, a beta-sheet rich oligomer, or protofibril, and a stable amyloid fibril. This work reviews the current literature that is relevant to two linked questions: which of these species is pathogenic, and what is the mechanism of neurotoxicity? The amyloid fibril, fibrillar aggregates, Lewy bodies, and the alpha-synuclein monomer, which is normally expressed at high levels, are all unlikely to be pathogenic, for reasons discussed here. We therefore favor a toxic protofibril scenario, and propose that the pathogenic species is transiently populated during the process of fibrillization. Toxicity may arise from pore-like protofibrils that cause membrane permeabilization. An approach to testing this hypothesis is discussed.
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Affiliation(s)
- Michael J Volles
- Center for Neurologic Diseases, Brigham and Women's Hospital, and Department of Neurology, Harvard Medical School, 65 Landsdowne Street, Cambridge, Massachusetts 02139, USA
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Mausset-Bonnefont AL, de Sèze R, Privat A. Immunohistochemistry as a tool for topographical semi-quantification of neurotransmitters in the brain. BRAIN RESEARCH. BRAIN RESEARCH PROTOCOLS 2003; 10:148-55. [PMID: 12565685 DOI: 10.1016/s1385-299x(02)00206-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Immunohistochemistry is a powerful tool to detect neurotransmitter (NT) presence in different brain structures with a high spatial resolution. However, it is only scarcely used in quantitative approach due to lack of reproducibility and sensitivity. We developed a protocol of NT detection based on immunohistochemistry and image analysis to show that this approach could also be useful to evaluate NT content variations. We focused our study on the GABAergic system in the cerebellum and measured different accurate parameters, namely the optical density (O.D.), the stained area and the number of immunoreactive cells in each cerebellar cell layer. In order to modify the GABA content, we used gamma-vinyl-GABA (GVG), an inhibitor of GABA-transaminase, known to dramatically increase GABA concentration in the central nervous system (CNS) and especially in the cerebellum. We observed a significant increase in the three parameters measured in the molecular and the granular layers of the cerebellum after treatment with GVG, reflecting the well-established increase in GABA content after such a treatment. Therefore, our technical approach allows not only a precise determination of the effects in particular cell layers but also a semi-quantification of GABA content variations. This technique could be suitable for monitoring NT variations following any treatment.
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Affiliation(s)
- Anne Laure Mausset-Bonnefont
- INSERM U336, Développement, Plasticité et Vieillissement du Système Nerveux, Université Montpellier II, Place Eugène Bataillon, B.P. 106, 34095 Montpellier Cedex 5, France.
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35
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Venero JL, Revuelta M, Atiki L, Santiago M, Toms-Camardiel MC, Cano J, Machado A. Evidence for dopamine-derived hydroxyl radical formation in the nigrostriatal system in response to axotomy. Free Radic Biol Med 2003; 34:111-23. [PMID: 12498986 DOI: 10.1016/s0891-5849(02)01191-7] [Citation(s) in RCA: 191] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We have evaluated the ability of the injured nigrostriatal dopaminergic system to produce highly reactive hydroxyl radicals ((*)OH) by the electrochemical detection of salicylate hydroxylation. Unilateral transection of the medial forebrain bundle transiently increased the formation of (*)OH in substantia nigra (SN) but not in striatum during the first 48 h postlesion, when most relevant changes in terms of oxidatively modified proteins take place. Short-term adaptive axotomy-induced changes in substantia nigra included downregulation of nigral tyrosine hydroxylase (TH) and dopamine transporter (DAT) mRNA expression and more intense TH immunoreactivity. Maintained inhibition of monoamine oxidase activity with deprenyl totally prevented the axotomy-induced formation of (*)OH, thus demonstrating the dopaminergic nature of these radicals. In contrast, deprenyl treatment, which is associated with a diminution in free radical production, failed to delay the onset of dopaminergic degeneration. This observation highlights the importance of being extremely cautious when analyzing parameters of oxidative stress and extrapolating them as a primary cause of cell death in the context of neurodegeneration. Long-term adaptive changes included a dramatic downregulation of DAT mRNA expression along with a moderate decrease in TH mRNA levels in SN. We anticipate a key regulatory role of the DAT to maximally optimize dopaminergic transmission in the synaptic cleft under conditions of degeneration.
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Affiliation(s)
- Jos L Venero
- Department of Biochemistry, Faculty of Pharmacy, University of Seville, Seville, Spain
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36
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Mausset AL, de Seze R, Montpeyroux F, Privat A. Effects of radiofrequency exposure on the GABAergic system in the rat cerebellum: clues from semi-quantitative immunohistochemistry. Brain Res 2001; 912:33-46. [PMID: 11520491 DOI: 10.1016/s0006-8993(01)02599-9] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The widespread use of cellular phones raises the problem of interaction of electromagnetic fields with the central nervous system (CNS). In order to measure these effects on neurotransmitter content in the CNS, we developed a protocol of neurotransmitter detection based on immunohistochemistry and image analysis. Gamma-vinyl-GABA (GVG), an inhibitor of the GABA-transaminase was injected in rats to increase GABA concentration in the CNS. The cellular GABA contents were then revealed by immunohistochemistry and semi-quantified by image analysis thanks to three parameters: optical density (O.D.), staining area, and number of positive cells. The increase in cerebellar GABA content induced by GVG 1200 mg/kg was reflected in these three parameters in the molecular and the granular layers. Therefore, control of immunohistochemistry parameters, together with appropriate image analysis, allowed both the location and the detection of variations in cellular neurotransmitter content. This protocol was used to investigate the effects of exposure to 900 MHz radiofrequencies on cerebellar GABA content. Both pulsed emission with a specific absorption rate (SAR) of 4 W/kg and continuous emission with high SAR (32 W/kg) were tested. We observed a selective diminution of the stained processes area in the Purkinje cell layer after exposure to pulsed radiofrequency and, in addition, a decrease in O.D. in the three cell layers after exposure to continuous waves. Whether this effect is, at least partly, due to a local heating of the tissues is not known. Overall, it appears that high energetic radiofrequency exposure induces a diminution in cellular GABA content in the cerebellum.
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Affiliation(s)
- A L Mausset
- Laboratoire de Biophysique Médicale, Faculté de Médecine de Nîmes, Avenue Kennedy, 30907 Cedex 2, Nîmes, France
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37
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Fran�ois C, Yelnik J, Tand� D, Agid Y, Hirsch E. Dopaminergic cell group A8 in the monkey: Anatomical organization and projections to the striatum. J Comp Neurol 1999. [DOI: 10.1002/(sici)1096-9861(19991122)414:3<334::aid-cne4>3.0.co;2-x] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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38
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Bezard E, Gross CE. Compensatory mechanisms in experimental and human parkinsonism: towards a dynamic approach. Prog Neurobiol 1998; 55:93-116. [PMID: 9618745 DOI: 10.1016/s0301-0082(98)00006-9] [Citation(s) in RCA: 162] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
This paper provides an overview of the compensatory mechanisms which come into action during experimental and human parkinsonism. The intrinsic properties of the dopaminergic neurones of the substantia nigra pars compacta (SNc) which degenerate during Parkinson's disease are described in detail. It is generally considered that the nigrostriatal pathway is principally responsible for the compensatory preservation of dopaminergic function. It is also becoming clear that the morphological characteristics of dopaminergic neurones and the dual character, synaptic and asynaptic, of striatal dopaminergic innervation engender two modes of transmission, wiring and volume, and that both these modes play a role in the preservation of dopaminergic function. The plasticity of the dopamine neurones, extrinsic or intrinsic to the striatum, can thus be regarded as another compensatory mechanism. Recent anatomical and electrophysiological studies have shown that the SNc receives both glutamatergic and cholinergic inputs. The dynamic role this innervation plays in compensatory mechanisms in the course of the disease is explained and discussed. Recent developments in the field of compensatory mechanisms speak for the urgence to develop a valid chronic model of Parkinson's disease, integrating all the clinical features, even resting tremor, and illustrating the gradual evolution of nigral degeneration observed in human Parkinson's disease. Only a dynamic approach to the physiopathological study of compensatory mechanisms in the basal ganglia will be capable of elucidating these complex questions.
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Affiliation(s)
- E Bezard
- Laboratoire de Neurophysiologie, CNRS UMR 5543, Université de Bordeaux II, France.
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39
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Sheline YI, Miller K, Bardgett ME, Csernansky JG. Higher Cerebrospinal Fluid MHPG in Subjects With Dementia of the Alzheimer Type: Relationship With Cognitive Dysfunction. THE AMERICAN JOURNAL OF GERIATRIC PSYCHIATRY 1998. [DOI: 10.1097/00019442-199805000-00009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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40
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Luo Y, Umegaki H, Wang X, Abe R, Roth GS. Dopamine induces apoptosis through an oxidation-involved SAPK/JNK activation pathway. J Biol Chem 1998; 273:3756-64. [PMID: 9452508 DOI: 10.1074/jbc.273.6.3756] [Citation(s) in RCA: 261] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Dopamine (DA) is a neurotransmitter, but it also exerts a neurotoxic effect under certain pathological conditions, including age-related neurodegeneration such as Parkinson's disease. By using both the 293 cell line and primary neonatal rat postmitotic striatal neuron cultures, we show here that DA induces apoptosis in a time- and concentration-dependent manner. Concomitant with the apoptosis, DA activates the JNK pathway, including increases in JNK activity, phosphorylation of c-Jun, and subsequent increase in c-Jun protein. This DA-induced JNK activation precedes apoptosis and is persistently sustained during the process of apoptosis. Transient expression of a dominant negative mutant SEK1(Lys --> Arg), an upstream kinase of JNK, prevents both DA-induced JNK activation and apoptosis. A dominant negative c-Jun mutant FLAGDelta169 also reduces DA-induced apoptotic cell death. Anti-oxidants N-acetylcysteine and catalase, which serve as scavengers of reactive oxygen species generated by metabolic DA oxidation, effectively block DA-induced JNK activation and subsequent apoptosis. Thus, our data suggest that DA triggers an apoptotic death program through an oxidative stress-involved JNK activation signaling pathway. Given the fact that the anti-oxidative defense system declines during aging, this molecular event may be implicated in the age-related striatal neuronal cell loss and age-related dopaminergic neurodegenerative disorders, such as Parkinson's and Huntington's diseases.
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Affiliation(s)
- Y Luo
- Molecular Physiology and Genetics Section, Gerontology Research Center, NIA, National Institutes of Health, Baltimore, Maryland 21224, USA.
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41
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Soriano MA, Justicia C, Ferrer I, Rodríguez-Farré E, Planas AM. Striatal infarction in the rat causes a transient reduction of tyrosine hydroxylase immunoreactivity in the ipsilateral substantia nigra. Neurobiol Dis 1998; 4:376-85. [PMID: 9440126 DOI: 10.1006/nbdi.1997.0166] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Dopaminergic neurons of the substantia nigra pars compacta were examined in the rat brain following striatal infarction subsequent to transient focal cerebral ischemia. Rats had the middle cerebral artery occluded for 2 h or were sham-operated, and tyrosine hydroxylase immunoreactivity was evaluated by Western blot and immunohistochemistry at different times ranging from 1 to 60 days after ischemia. The number of tyrosine hydroxylase-immunoreactive cells in the substantia nigra pars compacta was counted under the light microscope and compared to that in the contralateral side and controls. No changes of tyrosine hydroxylase immunoreactivity were detected in the ipsilateral versus the contralateral substantia nigra of sham-operated rats or 1 day after ischemia. However, a statistically significant reduction of tyrosine hydroxylase-immunoreactive cells became apparent in the ipsilateral compared with the contralateral substantia nigra at 7 and 14 days after ischemia. This reduction showed a clear recovery at 30 days after ischemia, and no signs of difference between the ipsilateral and the contralateral side were apparent by 60 days. Therefore, the reduction of tyrosine hydroxylase immunoreactivity in the ipsilateral substantia nigra was only transiently seen from 1 to 2 weeks following ischemia. The observed loss of tyrosine hydroxylase was not accompanied by signs of cell death or gliosis in the ipsilateral pars compacta. The present results show a transitory reduction of tyrosine hydroxylase immunoreactivity in the ipsilateral substantia nigra pars compacta after focal ischemia and suggest that striatal infarction causes a transient deficit of dopaminergic function.
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Affiliation(s)
- M A Soriano
- Departament de Farmacologia i Toxicologia, IIBB-CSIC, Universitat de Barcelona, Spain
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42
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Abstract
Neuronal degeneration occurs in the substantia nigra pars compacta (SNpc) of patients with Parkinson's disease and other Lewy body-associated disorders. Lewy bodies (LBs) are abnormal inclusions found in the SNpc and other neurons of these patients. It is not known what role LBs play in the disease process; they may be harmful to the neuron or simply an epiphenomenon of the disease process. We have previously shown that some of the neuronal death occurring in the SNpc of Lewy body-associated disorders resembles apoptosis. The present study was undertaken to determine whether apoptotic-like changes were more common in SNpc neurons with somal LBs compared to those without somal LBs. Substantia nigra from cases of Lewy body-associated disorders were labeled to colocalize apoptotic-like changes and LBs using in situ end-labeling and an anti-ubiquitin antibody. Three cases demonstrated that SNpc neurons with LBs in the perikarya had the same proportion of apoptotic-like changes as SNpc neurons without somal LBs. One case had no LB-containing SNpc neurons undergoing apoptotic-like cell death. The majority of SNpc neurons undergoing apoptotic-like cell death did not appear to contain somal LBs and thus may be dying before LB formation can occur. These results support the theory that the presence of a somal LB does not predispose a neuron to undergo apoptotic-like cell death.
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Affiliation(s)
- M M Tompkins
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta 30912, USA
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Joyce JN, Smutzer G, Whitty CJ, Myers A, Bannon MJ. Differential modification of dopamine transporter and tyrosine hydroxylase mRNAs in midbrain of subjects with Parkinson's, Alzheimer's with parkinsonism, and Alzheimer's disease. Mov Disord 1997; 12:885-97. [PMID: 9399211 DOI: 10.1002/mds.870120609] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The molecular characteristics of midbrain dopamine (DA) neurons have been extensively studied in Parkinson's disease (PD). No such studies of the characteristics of midbrain DA neurons in Alzheimer's disease (AD) or Alzheimer's disease with parkinsonism (AD/Park) have been published. We examined the levels of tyrosine hydroxylase (TH) protein, and the expression of TH and dopamine transporter (DAT) mRNAs, in midbrain neurons of PD, AD, and AD/Park cases. In PD, the loss of TH protein in the ventral tier of the substantia nigra pars compacta (SNpc) of the PD group in accompanied by severe losses in the number of neurons that express TH mRNA and DAT mRNA (74% loss). Remaining neurons show a shift to higher concentrations of TH mRNA but a shift to lower concentrations of DAT mRNA per cell. Hence, there is evidence that compensation in the remaining neurons can elevate concentrations of TH mRNA and lower DAT mRNA. Alternatively, there may be a predilection for a loss of neurons with high levels of DAT mRNA and low TH mRNA levels within the SNpc of PD cases. There was no change in TH protein but an elevation of TH mRNA concentrations per neuron without any change in concentrations of DAT mRNA in the AD group. The AD/Park group did not exhibit changes in the level of TH protein, but showed a small loss (26%) of neurons in the SNpc and a greater loss in other regions of the midbrain (43-53%). Remaining DA neurons showed a marked shift to lower concentrations of DAT mRNA per neuron and a nonsignificant shift in cellular concentration of TH mRNA to higher levels. This is consistent with our previous work showing that with AD/Park there is a significant reduction in the number of DAT sites located on DA terminals in the striatum, but the midbrain neurons have not died. Our results indicate that the differential regulation of mRNAs encoding TH and DAT is similar in the parkinsonian disorders (PD and AD/Park) even though the degree of cell death is very different. This might suggest that compensatory events occur in these DA neurons in AD/Park that are similar to those in PD and that result in differential effects on mRNAs encoding TH and DAT proteins.
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Affiliation(s)
- J N Joyce
- Thomas H. Christopher Center for Parkinson's Disease Research, Sun Health Research Institute, Sun City, Arizona, USA
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McRitchie DA, Cartwright HR, Halliday GM. Specific A10 dopaminergic nuclei in the midbrain degenerate in Parkinson's disease. Exp Neurol 1997; 144:202-13. [PMID: 9126172 DOI: 10.1006/exnr.1997.6418] [Citation(s) in RCA: 100] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Using unbiased quantitative techniques, we evaluated the effect of Parkinson's disease on the regional size and the number of tyrosine hydroxylase-producing neurons and all neurons in the midbrain A8 and A10 dopaminergic cell groups located adjacent to the substantia nigra. Seven patients with Lewy body Parkinson's disease were evaluated and compared with five controls. Four of the patients with Parkinson's disease had additional neuropathology, and the effect of concomitant pathology on A10 populations was also determined. Degeneration was not observed in the A8 regions of any patient, and only certain A10 nuclei were affected by the disease. The parabrachial pigmented nucleus situated dorsal to the substantial nigra, and the parapeduncular nucleus located rostromedially were significantly reduced by 40-50% in patients with Parkinson's disease. Few differences were found between patients with or without additional pathology, suggesting a similar pathogenic mechanism to that observed in the substantia nigra of these patients. However, patients with additional pathology also had serotonergic cell loss in the caudal linear nucleus. There was a reduction in tyrosine hydroxylase immunoreactivity but no overt neurodegeneration in other A10 regions, suggesting the disease may also influence the production of dopamine in some surviving neurons.
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Affiliation(s)
- D A McRitchie
- Prince of Wales Medical Research Institute, Randwick, New South Wales, Australia
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Gash DM, Zhang Z, Cass WA, Ovadia A, Simmerman L, Martin D, Russell D, Collins F, Hoffer BJ, Gerhardt GA. Morphological and functional effects of intranigrally administered GDNF in normal rhesus monkeys. J Comp Neurol 1995; 363:345-58. [PMID: 8847404 DOI: 10.1002/cne.903630302] [Citation(s) in RCA: 91] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Effects of a single injection of either 150 micrograms human recombinant glial cell line-derived neurotrophic factor (rGDNF) or vehicle into the right substantia nigra were analyzed in 12 normal adult female rhesus monkeys. The studies included evaluating whole animal behavior, electrochemical recordings of striatal dopamine release, neurochemical determinations of basal ganglia and nigral monoamine levels, and immunohistochemical staining of the nigrostriatal dopamine system. The behavioral effects over the 3-week observation period following trophic factor administration were small, with blinded observers unable to distinguish between GDNF- and vehicle-treated animals. Quantitative measurements did show that five of six trophic factor recipients experienced some weight loss and four of the six GDNF recipients displayed small, but significant, increases in daytime activity levels. In vivo electrochemical recordings in the ipsilateral caudate and putamen 3 weeks after GDNF administration revealed increased potassium-evoked release of dopamine in trophic factor recipients. In a second series of animals killed at the same time, dopamine levels in the substantia nigra and ventral tegmental area of GDNF recipients were significantly increased, with ipsilateral values more than 200% higher than contralateral and control levels. Levels of the dopamine metabolite HVA were significantly elevated in the substantia nigra, ventral tegmental area, and caudate nucleus ipsilateral to the trophic factor injection. There was a trend toward increased HVA levels in the ipsilateral putamen, nucleus accumbens, and globus pallidus in GDNF-treated animals, but the ratios of HVA to dopamine were not significantly different between vehicle- and GDNF-treated recipients. Although some tissue damage from the delivery of concentrated trophic factor was evident, dopamine neurons remained in an adjacent to the injection site. In the substantia nigra ipsilateral to GDNF administration, dopamine-neuron perikaryal size was significantly increased, along with a significant increase in tyrosine hydroxylase-positive axons and dendrites. We conclude that, in the adult rhesus monkey, a single intranigral GDNF injection induces a significant upregulation of mesencephalic dopamine neurons which lasts for weeks.
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Affiliation(s)
- D M Gash
- Department of Anatomy and Neurobiology, University of Kentucky, Lexington 40536, USA
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Thibaut F, Faucheux BA, Marquez J, Villares J, Menard JF, Agid Y, Hirsch EC. Regional distribution of monoamine vesicular uptake sites in the mesencephalon of control subjects and patients with Parkinson's disease: a postmortem study using tritiated tetrabenazine. Brain Res 1995; 692:233-43. [PMID: 8548309 DOI: 10.1016/0006-8993(95)00674-f] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The distribution of the vesicular monoamine transporter was investigated post mortem in the human ventral mesencephalon of control subjects (n = 7) and patients with Parkinson's disease (n = 4) using tritiated dihydrotetrabenzine binding and autoradiography. Tritiated dihydrotetrabenazine binding was characterized by a single class of sites with a Kd of 7 nM and a Bmax of 180 fmol/mg of protein in the substantia nigra. Tritiated dihydrotetrabenazine binding sites were heterogeneously distributed in the mesencephalon of control subjects: the density of tritiated dihydrotetrabenazine binding sites was high in the substantia nigra pars compacta, locus coeruleus and nucleus raphe dorsalis, moderate in the ventral tegmental area and low in the substantia nigra pars reticulata and catecholaminergic cell group A8. Within the substantia nigra, a zone with maximal density of tritiated dihydrotetrabenazine binding, two times higher than the mean estimate for the whole substantia nigra pars compacta, was detected in the medial part of the structure. The anatomical organization of the human ventral mesencephalon was analyzed on adjacent sections stained for acetylcholinesterase histochemistry and tyrosine hydroxylase immunohistochemistry. Tritiated dihydrotetrabenazine binding displayed the same characteristic regional pattern of distribution as that observed with tyrosine hydroxylase immunohistochemistry except in the nucleus raphe dorsalis, where no tyrosine hydroxylase immunoreactivity was detected. In parkinsonian brains, the level of tritiated dihydrotetrabenazine binding was dramatically decreased in all regions of the ventral mesencephalon analyzed except in the substantia nigra pars reticulata. In the substantia nigra pars compacta, the reduction was by 55% for the whole structure and by 65% in its medial zone, where binding site density was maximal. In most nigral subsectors analyzed, the decrease in density of tritiated dihydrotetrabenazine binding sites reached the level expected given the loss of tyrosine hydroxylase-positive cells observed. By contrast, the ratio of [3H]dihydrotetrabenazine binding to the number of tyrosine hydroxylase positive neurons was significantly increased in the zone of high [3H]dihydrotetrabenazine binding sites. This relative sparing of tritiated dihydrotetrabenazine binding sites may be due either to the contribution of other monoaminergic neurons such as serotoninergic neurons or more likely to hyperactivity of the still surviving dopaminergic neurons.
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Affiliation(s)
- F Thibaut
- INSERM U289, Hôpital de la Salpêtrière, Paris, France
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Schneider JS, Kean A, DiStefano L. GM1 ganglioside rescues substantia nigra pars compacta neurons and increases dopamine synthesis in residual nigrostriatal dopaminergic neurons in MPTP-treated mice. J Neurosci Res 1995; 42:117-23. [PMID: 8531220 DOI: 10.1002/jnr.490420113] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
GM1 ganglioside has been shown to stimulate recovery of the damaged dopamine system under a number of different circumstances. In addition to rescue of damaged dopamine neurons, the present study assessed the ability of GM1 to enhance the synthesis of dopamine in remaining nigrostriatal neurons following 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) exposure. There was a significantly greater accumulation of L-dopa 30 min after aromatic amino acid decarboxylase inhibition with NSD-1015 (100 mg/kg) and an increase in the ratio of L-dopa to dopamine in MPTP+GM1-treated mice than in mice that received only MPTP. This effect of GM1 on dopamine synthesis was dependent upon the degree of initial damage to the nigrostriatal dopamine system. That is, the GM1 effect on dopamine synthesis could not be demonstrated in mice with greater than 95% striatal dopamine loss and 75% substantia nigra dopamine neuron loss. These results suggest that in addition to previously reported effects of GM1 on rescue and repair of dopaminergic neurons, GM1 may also have the ability to enhance dopamine synthesis in residual dopaminergic neurons. Direct effects on dopamine neurochemistry may contribute to functional improvement seen after GM1 treatment in various models of parkinsonism.
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Affiliation(s)
- J S Schneider
- Center for Neurological Research of the Department of Neurology, Hahnemann University, Philadelphia, Pennsylvania 19102, USA
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48
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Przedborski S, Levivier M, Jiang H, Ferreira M, Jackson-Lewis V, Donaldson D, Togasaki DM. Dose-dependent lesions of the dopaminergic nigrostriatal pathway induced by intrastriatal injection of 6-hydroxydopamine. Neuroscience 1995; 67:631-47. [PMID: 7675192 DOI: 10.1016/0306-4522(95)00066-r] [Citation(s) in RCA: 350] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Animal models with partial lesions of the dopaminergic nigrostriatal pathway may be useful for developing neuroprotective and neurotrophic therapies for Parkinson's disease. To develop such a model, different doses of 6-hydroxydopamine (0.0, 0.625, 1.25, 2.5 and 5.0 micrograms/microliters in 3.5 microliters of saline) were unilaterally injected into the striatum of rats. Animals that received 1.25 to 5.0 micrograms/microliters 6-hydroxydopamine displayed dose-dependent amphetamine and apomorphine-induced circling. 6-Hydroxydopamine also caused dose-dependent reductions in [3H]mazindol-labeled dopamine uptake sites in the lesioned striatum and ipsilateral substantia nigra pars compacta (up to 93% versus contralateral binding), with smaller losses in the nucleus accumbens, olfactory tubercle and ventral tegmental area. In the substantia nigra pars compacta and the ventral tegmental area, the number of Nissl-stained neurons decreases in parallel with the reduction in [3H]mazindol binding. The reduction in [3H]mazindol binding in the striatum and the nucleus accumbens, and the reduction in [3H]mazindol binding and in the number of Nissl-stained neurons in the substantia nigra pars compacta and the ventral tegmental area is stable for up to 12 weeks after the lesion. Macroscopically, forebrain coronal sections showed normal morphology, except for rats receiving 5.0 micrograms/microliters 6-hydroxydopamine in which striatal cross-sectional area was reduced, suggesting that this high dose non-specifically damages intrinsic striatal neurons. Nissl-stained sections revealed an area of neuronal loss and intense gliosis centered around the needle track, which increased in size with the dose of neurotoxin. Striatal [3H]sulpiride binding was increased by 2.5 micrograms/microliters and 5.0 micrograms/microliters 6-hydroxydopamine, suggesting up-regulation of dopamine D2 receptors. Striatal binding of [3H]CGS 21680-labeled adenosine A2a receptors, but not of [3H]SCH 23390-labeled dopamine D1 receptors, was reduced at the highest dose, suggesting preservation of the striatal intrinsic neurons with the lower doses. This study indicates that intrastriatal injection of different doses of 6-hydroxydopamine can be used to cause increasing amounts of dopamine denervation, which could model Parkinson's disease of varying degrees of severity. Injecting 3.5 microliters of 2.5 micrograms/microliters 6-hydroxydopamine appears to be particularly useful as a general model of early Parkinson's disease, since it induces a lesion characterized by robust drug-induced rotation, changes in binding consistent with approximately 70% dopamine denervation, approximately 19% dopamine D22 receptor up-regulation, negligible intrinsic striatal damage and stability for at least 12 weeks. This study outlines a technique for inducing partial lesions of the nigrostriatal dopamine pathway in rats.(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- S Przedborski
- Department of Neurology, College of Physicians & Surgeons, Columbia University, New York, NY 10032, USA
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Murray AM, Weihmueller FB, Marshall JF, Hurtig HI, Gottleib GL, Joyce JN. Damage to dopamine systems differs between Parkinson's disease and Alzheimer's disease with parkinsonism. Ann Neurol 1995; 37:300-12. [PMID: 7695230 DOI: 10.1002/ana.410370306] [Citation(s) in RCA: 98] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Parkinsonism occurs in approximately 35 to 40% of patients with Alzheimer's disease (AD) even with little or no neuronal degeneration in the substantia nigra, which in idiopathic Parkinson's disease (PD) results in the severe loss of striatal dopamine transporter sites. It is not known if there is a loss of striatal dopamine transporter sites in AD with coexistent parkinsonism (AD/parkinsonism). We quantified the pattern of these sites in the striatum and midbrain of patients with the clinical diagnosis of PD, AD, and AD/parkinsonism in comparison with a group of age-matched control subjects. We also quantified the number of D2 receptors and the levels of tyrosine hydroxylase in the substantia nigra and ventral tegmental area of the same groups. The results showed that in AD the loss of dopamine transporter sites was restricted to the nucleus accumbens. The loss of these sites in the AD/parkinsonism group was more extensive than in the AD group, with the most severe losses in the rostral caudate and putamen and least in the caudal caudate and putamen. While the PD group showed an equally severe reduction in numbers of sites, the caudal to rostral gradient of loss differed from that in the AD/parkinsonism group. The PD group also showed a marked loss of dopamine transporter sites, tyrosine hydroxylase, and D2 autoreceptors (located on dopamine neurons) in the substantia nigra and ventral tegmental area. In contrast, no reductions in dopamine transporter sites, tyrosine hydroxylase, and D2 autoreceptors were observed in the substantia nigra and ventral tegmental area of the AD or AD/parkinsonism groups. Thus, the loss of striatal dopamine transporter sites in AD/parkinsonism may be related to the clinical parkinsonian symptoms. However, the loss is not simply the result of neuronal degeneration in the substantia nigra, but must derive from other processes.
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Affiliation(s)
- A M Murray
- Department of Psychiatry, University of Pennsylvania School of Medicine, Philadelphia 19104-6141
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Mouatt-Prigent A, Agid Y, Hirsch EC. Does the calcium binding protein calretinin protect dopaminergic neurons against degeneration in Parkinson's disease? Brain Res 1994; 668:62-70. [PMID: 7704619 DOI: 10.1016/0006-8993(94)90511-8] [Citation(s) in RCA: 83] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Parkinson's disease (PD) is characterized by a heterogeneous loss of dopaminergic neurons in the human mesencephalon affecting mainly the substantia nigra pars compacta (SNpc) and to a lesser extent the other dopaminergic cell groups. A rise in intracellular calcium concentrations represents one of the final events leading to nerve cell death. Calbindin D28k, a protein capable of buffering intracellular calcium concentrations is present in the dopaminergic neurons that are selectively preserved in PD but not in those that degenerate. To determine whether other calcium-binding proteins also represent putative protective factors of dopaminergic neurons in PD, we analyzed immunohistochemically the distribution of calretinin-containing (CR+) neurons, in the human mesencephalon of three control subjects and four patients with PD. No significant differences were observed between the number of CR+ neurons in the two subject groups. Sequential double immunostaining for calretinin and tyrosine hydroxylase showed a variable proportion of CR+ neurons among dopaminergic neurons: moderate co-localization was found in catecholaminergic cell group A8 and in the dorsal part of the ventral tegmental area (VTA) and low co-localization in the SNpc, the ventral part of the VTA and the central gray substance. This indicates that calretinin may only protect some dopaminergic neurons against degeneration in PD. Yet, in the SNpc a selective preservation of CR+ dopaminergic neurons was observed, suggesting a neuroprotective role in some dopaminergic cell groups only.
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