1
|
See WZC, Naidu R, Tang KS. Paraquat and Parkinson's Disease: The Molecular Crosstalk of Upstream Signal Transduction Pathways Leading to Apoptosis. Curr Neuropharmacol 2024; 22:140-151. [PMID: 36703582 DOI: 10.2174/1570159x21666230126161524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 12/21/2022] [Accepted: 12/26/2022] [Indexed: 01/28/2023] Open
Abstract
Parkinson's disease (PD) is a heterogeneous disease involving a complex interaction between genes and the environment that affects various cellular pathways and neural networks. Several studies have suggested that environmental factors such as exposure to herbicides, pesticides, heavy metals, and other organic pollutants are significant risk factors for the development of PD. Among the herbicides, paraquat has been commonly used, although it has been banned in many countries due to its acute toxicity. Although the direct causational relationship between paraquat exposure and PD has not been established, paraquat has been demonstrated to cause the degeneration of dopaminergic neurons in the substantia nigra pars compacta. The underlying mechanisms of the dopaminergic lesion are primarily driven by the generation of reactive oxygen species, decrease in antioxidant enzyme levels, neuroinflammation, mitochondrial dysfunction, and ER stress, leading to a cascade of molecular crosstalks that result in the initiation of apoptosis. This review critically analyses the crucial upstream molecular pathways of the apoptotic cascade involved in paraquat neurotoxicity, including mitogenactivated protein kinase (MAPK), phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/AKT, mammalian target of rapamycin (mTOR), and Wnt/β-catenin signaling pathways.
Collapse
Affiliation(s)
- Wesley Zhi Chung See
- Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, 47500 Bandar Sunway, Selangor, Malaysia
| | - Rakesh Naidu
- Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, 47500 Bandar Sunway, Selangor, Malaysia
| | - Kim San Tang
- School of Pharmacy, Monash University Malaysia, 47500 Bandar Sunway, Selangor, Malaysia
| |
Collapse
|
2
|
Costa G, Serra M, Maccioni R, Casu MA, Kasture SB, Acquas E, Morelli M. Withania somnifera influences MDMA-induced hyperthermic, cognitive, neurotoxic and neuroinflammatory effects in mice. Biomed Pharmacother 2023; 161:114475. [PMID: 36905810 DOI: 10.1016/j.biopha.2023.114475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 03/01/2023] [Accepted: 03/02/2023] [Indexed: 03/11/2023] Open
Abstract
Withania somnifera (WS) is utilized in Ayurvedic medicine owing to its central and peripheral beneficial properties. Several studies have accrued indicating that the recreational amphetamine-related drug (+/-)- 3,4-methylenedioxymethamphetamine (MDMA; Ecstasy) targets the nigrostriatal dopaminergic system in mice, inducing neurodegeneration and gliosis, causing acute hyperthermia and cognitive impairment. This study aimed to investigate the effect of a standardized extract of W. somnifera (WSE) on MDMA-induced neurotoxicity, neuroinflammation, memory impairment and hyperthermia. Mice received a 3-day pretreatment with vehicle or WSE. Thereafter, vehicle- and WSE-pretreated mice were randomly divided into four groups: saline, WSE, MDMA alone, WSE plus MDMA. Body temperature was recorded throughout treatment, and memory performance was assessed by a novel object recognition (NOR) task at the end of treatment. Thereafter, immunohistochemistry was performed to evaluate in the substantia nigra pars compacta (SNc) and striatum the levels of tyrosine hydroxylase (TH), as marker of dopaminergic degeneration, and of glial fibrillary acidic protein (GFAP) and TMEM119, as markers of astrogliosis or microgliosis, respectively. MDMA-treated mice showed a decrease in TH-positive neurons and fibers in the SNc and striatum respectively, an increase in gliosis and body temperature, and a decrease in NOR performance, irrespective of vehicle or WSE pretreatment. Acute WSE plus MDMA counteracted the modifications in TH-positive cells in SNc, GFAP-positive cells in striatum, TMEM in both areas and NOR performance, as compared to MDMA alone, while no differences were observed as compared to saline. Results indicate that WSE acutely administered in combination with MDMA, but not as pretreatment, protects mice against the noxious central effects of MDMA.
Collapse
Affiliation(s)
- Giulia Costa
- Department of Biomedical Sciences, Section of Neuroscience, University of Cagliari, Cagliari, Italy.
| | - Marcello Serra
- Department of Biomedical Sciences, Section of Neuroscience, University of Cagliari, Cagliari, Italy
| | - Riccardo Maccioni
- Department of Life and Environmental Sciences, University of Cagliari, Cagliari, Italy; Department of Immunology and Microbiology, Scripps Research, La Jolla, CA, USA
| | - Maria Antonietta Casu
- National Research Council of Italy, Institute of Translational Pharmacology, UOS of Cagliari, Scientific and Technological Park of Sardinia POLARIS, Pula, Italy
| | - Sanjay B Kasture
- Rajarshi Shahu College of Pharmacy, Buldhana, Maharashtra, India
| | - Elio Acquas
- Department of Life and Environmental Sciences, University of Cagliari, Cagliari, Italy
| | - Micaela Morelli
- Department of Biomedical Sciences, Section of Neuroscience, University of Cagliari, Cagliari, Italy; National Research Council of Italy, Neuroscience Institute, Cagliari, Italy
| |
Collapse
|
3
|
Wang H, Chen G, Ahn EH, Xia Y, Kang SS, Liu X, Liu C, Han MH, Chen S, Ye K. C/EBPβ/AEP is age-dependently activated in Parkinson's disease and mediates α-synuclein in the gut and brain. NPJ Parkinsons Dis 2023; 9:1. [PMID: 36609384 PMCID: PMC9822984 DOI: 10.1038/s41531-022-00430-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 11/11/2022] [Indexed: 01/09/2023] Open
Abstract
Parkinson's disease (PD) is the most common neurodegenerative motor disorder, and its pathologic hallmarks include extensive dopaminergic neuronal degeneration in the Substantia nigra associated with Lewy bodies, predominantly consisting of phosphorylated and truncated α-Synuclein (α-Syn). Asparagine endopeptidase (AEP) cleaves human α-Syn at N103 residue and promotes its aggregation, contributing to PD pathogenesis. However, how AEP mediates Lewy body pathologies during aging and elicits PD onset remains incompletely understood. Knockout of AEP or C/EBPβ from α-SNCA mice, and their chronic rotenone exposure models were used, and the mechanism of α-Syn from the gut that spread to the brain was observed. Here we report that C/EBPβ/AEP pathway, aggravated by oxidative stress, is age-dependently activated and cleaves α-Syn N103 and regulates Lewy body-like pathologies spreading from the gut into the brain in human α-SNCA transgenic mice. Deletion of C/EBPβ or AEP substantially diminished the oxidative stress, neuro-inflammation, and PD pathologies, attenuating motor dysfunctions in aged α-SNCA mice. Noticeably, PD pathologies initiate in the gut and progressively spread into the brain. Chronic gastric exposure to a low dose of rotenone initiates Lewy body-like pathologies in the gut that propagate into the brain in a C/EBPβ/AEP-dependent manner. Hence, our studies demonstrate that C/EBPβ/AEP pathway is critical for mediating Lewy body pathology progression in PD.
Collapse
Affiliation(s)
- Hualong Wang
- grid.16821.3c0000 0004 0368 8293Department of Neurology and Institute of Neurology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200025 China ,grid.452458.aDepartment of Neurology, The First Hospital of Hebei Medical University (Department of Neurology, Hebei Hospital of Xuanwu Hospital Capital Medical University), Brain Aging and Cognitive Neuroscience Laboratory of Hebei Province, Neuromedical Technology Innovation Center of Hebei Province, Shijiazhuang, 050031 Hebei P. R. China ,grid.189967.80000 0001 0941 6502Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia 30322 USA
| | - Guiqin Chen
- grid.189967.80000 0001 0941 6502Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia 30322 USA ,grid.412632.00000 0004 1758 2270Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, Hubei Province 430060 China
| | - Eun Hee Ahn
- grid.189967.80000 0001 0941 6502Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia 30322 USA ,grid.256753.00000 0004 0470 5964Department of Physiology, College of Medicine, Hallym University, Hallymdaehak-gil, Chuncheon-si, Gangwon-Do, 24252, South Korea
| | - Yiyuan Xia
- grid.189967.80000 0001 0941 6502Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia 30322 USA
| | - Seong Su Kang
- grid.189967.80000 0001 0941 6502Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia 30322 USA
| | - Xia Liu
- grid.189967.80000 0001 0941 6502Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia 30322 USA
| | - Chang Liu
- grid.458489.c0000 0001 0483 7922CAS Key Laboratory of Brain Connectome and Manipulation, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong 518055 China ,grid.458489.c0000 0001 0483 7922Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518000, China
| | - Ming-Hu Han
- grid.458489.c0000 0001 0483 7922Department of Mental Health and Public Health, Faculty of Life and Health Sciences, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong 518055 China
| | - Shengdi Chen
- grid.16821.3c0000 0004 0368 8293Department of Neurology and Institute of Neurology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200025 China
| | - Keqiang Ye
- grid.189967.80000 0001 0941 6502Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia 30322 USA ,grid.458489.c0000 0001 0483 7922Department of Biology, Faculty of Life and Health Sciences, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong 518055 China
| |
Collapse
|
4
|
Bentea E, De Pauw L, Verbruggen L, Winfrey LC, Deneyer L, Moore C, Albertini G, Sato H, Van Eeckhaut A, Meshul CK, Massie A. Aged xCT-Deficient Mice Are Less Susceptible for Lactacystin-, but Not 1-Methyl-4-Phenyl-1,2,3,6- Tetrahydropyridine-, Induced Degeneration of the Nigrostriatal Pathway. Front Cell Neurosci 2022; 15:796635. [PMID: 34975413 PMCID: PMC8718610 DOI: 10.3389/fncel.2021.796635] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Accepted: 11/24/2021] [Indexed: 12/23/2022] Open
Abstract
The astrocytic cystine/glutamate antiporter system x c - (with xCT as the specific subunit) imports cystine in exchange for glutamate and has been shown to interact with multiple pathways in the brain that are dysregulated in age-related neurological disorders, including glutamate homeostasis, redox balance, and neuroinflammation. In the current study, we investigated the effect of genetic xCT deletion on lactacystin (LAC)- and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced degeneration of the nigrostriatal pathway, as models for Parkinson's disease (PD). Dopaminergic neurons of adult xCT knock-out mice (xCT-/-) demonstrated an equal susceptibility to intranigral injection of the proteasome inhibitor LAC, as their wild-type (xCT+/+) littermates. Contrary to adult mice, aged xCT-/- mice showed a significant decrease in LAC-induced degeneration of nigral dopaminergic neurons, depletion of striatal dopamine (DA) and neuroinflammatory reaction, compared to age-matched xCT+/+ littermates. Given this age-related protection, we further investigated the sensitivity of aged xCT-/- mice to chronic and progressive MPTP treatment. However, in accordance with our previous observations in adult mice (Bentea et al., 2015a), xCT deletion did not confer protection against MPTP-induced nigrostriatal degeneration in aged mice. We observed an increased loss of nigral dopaminergic neurons, but equal striatal DA denervation, in MPTP-treated aged xCT-/- mice when compared to age-matched xCT+/+ littermates. To conclude, we reveal age-related protection against proteasome inhibition-induced nigrostriatal degeneration in xCT-/- mice, while xCT deletion failed to protect nigral dopaminergic neurons of aged mice against MPTP-induced toxicity. Our findings thereby provide new insights into the role of system x c - in mechanisms of dopaminergic cell loss and its interaction with aging.
Collapse
Affiliation(s)
- Eduard Bentea
- Laboratory of Neuro-Aging and Viro-Immunotherapy, Vrije Universiteit Brussel, Brussels, Belgium
| | - Laura De Pauw
- Laboratory of Neuro-Aging and Viro-Immunotherapy, Vrije Universiteit Brussel, Brussels, Belgium
| | - Lise Verbruggen
- Laboratory of Neuro-Aging and Viro-Immunotherapy, Vrije Universiteit Brussel, Brussels, Belgium
| | - Lila C Winfrey
- Neurocytology Laboratory, Veterans Affairs Medical Center, Research Services, Portland, OR, United States
| | - Lauren Deneyer
- Laboratory of Neuro-Aging and Viro-Immunotherapy, Vrije Universiteit Brussel, Brussels, Belgium
| | - Cynthia Moore
- Neurocytology Laboratory, Veterans Affairs Medical Center, Research Services, Portland, OR, United States
| | - Giulia Albertini
- Laboratory of Neuro-Aging and Viro-Immunotherapy, Vrije Universiteit Brussel, Brussels, Belgium
| | - Hideyo Sato
- Department of Medical Technology, Niigata University, Niigata, Japan
| | - Ann Van Eeckhaut
- Research Group Experimental Pharmacology, Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Vrije Universiteit Brussel, Brussels, Belgium
| | - Charles K Meshul
- Neurocytology Laboratory, Veterans Affairs Medical Center, Research Services, Portland, OR, United States.,Department of Behavioral Neuroscience and Pathology, Oregon Health and Science University, Portland, OR, United States
| | - Ann Massie
- Laboratory of Neuro-Aging and Viro-Immunotherapy, Vrije Universiteit Brussel, Brussels, Belgium
| |
Collapse
|
5
|
Ganesan S, Parvathi VD. Deconstructing the molecular genetics behind the PINK1/Parkin axis in Parkinson’s disease using Drosophila melanogaster as a model organism. EGYPTIAN JOURNAL OF MEDICAL HUMAN GENETICS 2021. [DOI: 10.1186/s43042-021-00208-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Abstract
Background
Parkinson’s disease (PD) is a multifactorial neurodegenerative disorder marked by the death of nigrostriatal dopaminergic neurons in response to the compounding effects of oxidative stress, mitochondrial dysfunction and protein aggregation. Transgenic Drosophila models have been used extensively to decipher the underlying genetic interactions that exacerbate neural health in PD. Autosomal recessive forms of the disease have been linked to mutations in the serine/threonine kinase PINK1(PTEN-Induced Putative Kinase 1) and E3 ligase Parkin, which function in an axis that is conserved in flies. This review aims to probe the current understanding of PD pathogenesis via the PINK1/Parkin axis while underscoring the importance of several molecular and pharmacologic rescues brought to light through studies in Drosophila.
Main body
Mutations in PINK1 and Parkin have been shown to affect the axonal transport of mitochondria within dopaminergic neurons and perturb the balance between mitochondrial fusion/fission resulting in abnormal mitochondrial morphology. As per studies in flies, ectopic expression of Fwd kinase and Atg-1 to promote fission and mitophagy while suppressing fusion via MUL1 E3 ligase may aid to halt mitochondrial aggregation and prolong the survival of dopaminergic neurons. Furthermore, upregulation of Hsp70/Hsp90 chaperone systems (Trap1, CHIP) to target misfolded mitochondrial respiratory complexes may help to preserve their bioenergetic capacity. Accumulation of reactive oxygen species as a consequence of respiratory complex dysfunction or antioxidant enzyme deficiency further escalates neural death by inducing apoptosis, lipid peroxidation and DNA damage. Fly studies have reported the induction of canonical Wnt signalling to enhance the activity of transcriptional co-activators (PGC1α, FOXO) which induce the expression of antioxidant enzymes. Enhancing the clearance of free radicals via uncoupling proteins (UCP4) has also been reported to ameliorate oxidative stress-induced cell death in PINK1/Parkin mutants.
Conclusion
While these novel mechanisms require validation through mammalian studies, they offer several explanations for the factors propagating dopaminergic death as well as promising insights into the therapeutic importance of transgenic fly models in PD.
Collapse
|
6
|
Thirumalai D, Lee S, Kwon M, Paik HJ, Lee J, Chang SC. Disposable Voltammetric Sensor Modified with Block Copolymer-Dispersed Graphene for Simultaneous Determination of Dopamine and Ascorbic Acid in Ex Vivo Mouse Brain Tissue. BIOSENSORS-BASEL 2021; 11:bios11100368. [PMID: 34677324 PMCID: PMC8534151 DOI: 10.3390/bios11100368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 09/26/2021] [Accepted: 09/30/2021] [Indexed: 12/02/2022]
Abstract
Dopamine (DA) and ascorbic acid (AA) are two important biomarkers with similar oxidation potentials. To facilitate their simultaneous electrochemical detection, a new voltammetric sensor was developed by modifying a screen-printed carbon electrode (SPCE) with a newly synthesized block copolymer (poly(DMAEMA-b-styrene), PDbS) as a dispersant for reduced graphene oxide (rGO). The prepared PDbS–rGO and the modified SPCE were characterized using a range of physical and electrochemical techniques including Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, cyclic voltammetry, electrochemical impedance spectroscopy, and linear sweep voltammetry. Compared to the bare SPCE, the PDbS–rGO-modified SPCE (PDbS–rGO/SPCE) showed better sensitivity and peak-to-peak separation for DA and AA in mixed solutions. Under the optimum conditions, the dynamic linear ranges for DA and AA were 0.1–300 and 10–1100 µM, and the detection limits were 0.134 and 0.88 µM (S/N = 3), respectively. Furthermore, PDbS–rGO/SPCE exhibited considerably enhanced anti-interference capability, high reproducibility, and storage stability for four weeks. The practical potential of the PDbS–rGO/SPCE sensor for measuring DA and AA was demonstrated using ex vivo brain tissues from a Parkinson’s disease mouse model and the control.
Collapse
Affiliation(s)
- Dinakaran Thirumalai
- Department of Cogno-Mechatronics Engineering, College of Nanoscience and Nanotechnology, Pusan National University, Busan 46241, Korea;
| | - Seulah Lee
- College of Pharmacy, Pusan National University, Busan 46241, Korea; (S.L.); (J.L.)
| | - Minho Kwon
- Department of Polymer Science and Engineering, Pusan National University, Busan 46241, Korea; (M.K.); (H.-j.P.)
| | - Hyun-jong Paik
- Department of Polymer Science and Engineering, Pusan National University, Busan 46241, Korea; (M.K.); (H.-j.P.)
| | - Jaewon Lee
- College of Pharmacy, Pusan National University, Busan 46241, Korea; (S.L.); (J.L.)
| | - Seung-Cheol Chang
- Department of Cogno-Mechatronics Engineering, College of Nanoscience and Nanotechnology, Pusan National University, Busan 46241, Korea;
- Correspondence:
| |
Collapse
|
7
|
Tokarew JM, El-Kodsi DN, Lengacher NA, Fehr TK, Nguyen AP, Shutinoski B, O’Nuallain B, Jin M, Khan JM, Ng ACH, Li J, Jiang Q, Zhang M, Wang L, Sengupta R, Barber KR, Tran A, Im DS, Callaghan S, Park DS, Zandee S, Dong X, Scherzer CR, Prat A, Tsai EC, Takanashi M, Hattori N, Chan JA, Zecca L, West AB, Holmgren A, Puente L, Shaw GS, Toth G, Woulfe JM, Taylor P, Tomlinson JJ, Schlossmacher MG. Age-associated insolubility of parkin in human midbrain is linked to redox balance and sequestration of reactive dopamine metabolites. Acta Neuropathol 2021; 141:725-754. [PMID: 33694021 PMCID: PMC8043881 DOI: 10.1007/s00401-021-02285-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 01/11/2021] [Accepted: 01/13/2021] [Indexed: 12/31/2022]
Abstract
The mechanisms by which parkin protects the adult human brain from Parkinson disease remain incompletely understood. We hypothesized that parkin cysteines participate in redox reactions and that these are reflected in its posttranslational modifications. We found that in post mortem human brain, including in the Substantia nigra, parkin is largely insoluble after age 40 years; this transition is linked to its oxidation, such as at residues Cys95 and Cys253. In mice, oxidative stress induces posttranslational modifications of parkin cysteines that lower its solubility in vivo. Similarly, oxidation of recombinant parkin by hydrogen peroxide (H2O2) promotes its insolubility and aggregate formation, and in exchange leads to the reduction of H2O2. This thiol-based redox activity is diminished by parkin point mutants, e.g., p.C431F and p.G328E. In prkn-null mice, H2O2 levels are increased under oxidative stress conditions, such as acutely by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine toxin exposure or chronically due to a second, genetic hit; H2O2 levels are also significantly increased in parkin-deficient human brain. In dopamine toxicity studies, wild-type parkin, but not disease-linked mutants, protects human dopaminergic cells, in part through lowering H2O2. Parkin also neutralizes reactive, electrophilic dopamine metabolites via adduct formation, which occurs foremost at the primate-specific residue Cys95. Further, wild-type but not p.C95A-mutant parkin augments melanin formation in vitro. By probing sections of adult, human midbrain from control individuals with epitope-mapped, monoclonal antibodies, we found specific and robust parkin reactivity that co-localizes with neuromelanin pigment, frequently within LAMP-3/CD63+ lysosomes. We conclude that oxidative modifications of parkin cysteines are associated with protective outcomes, which include the reduction of H2O2, conjugation of reactive dopamine metabolites, sequestration of radicals within insoluble aggregates, and increased melanin formation. The loss of these complementary redox effects may augment oxidative stress during ageing in dopamine-producing cells of mutant PRKN allele carriers, thereby enhancing the risk of Parkinson’s-linked neurodegeneration.
Collapse
|
8
|
Strong MD, Hart MD, Tang TZ, Ojo BA, Wu L, Nacke MR, Agidew WT, Hwang HJ, Hoyt PR, Bettaieb A, Clarke SL, Smith BJ, Stoecker BJ, Lucas EA, Lin D, Chowanadisai W. Role of zinc transporter ZIP12 in susceptibility-weighted brain magnetic resonance imaging (MRI) phenotypes and mitochondrial function. FASEB J 2020; 34:10702-12725. [PMID: 32716562 DOI: 10.1096/fj.202000772r] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 07/01/2020] [Accepted: 07/10/2020] [Indexed: 12/16/2022]
Abstract
Brain zinc dysregulation is linked to many neurological disorders. However, the mechanisms regulating brain zinc homeostasis are poorly understood. We performed secondary analyses of brain MRI GWAS and exome sequencing data from adults in the UK Biobank. Coding ZIP12 polymorphisms in zinc transporter ZIP12 (SLC39A12) were associated with altered brain susceptibility weighted MRI (swMRI). Conditional and joint association analyses revealed independent GWAS signals in linkage disequilibrium with 2 missense ZIP12 polymorphisms, rs10764176 and rs72778328, with reduced zinc transport activity. ZIP12 rare coding variants predicted to be deleterious were associated with similar impacts on brain swMRI. In Neuro-2a cells, ZIP12 deficiency by short hairpin RNA (shRNA) depletion or CRISPR/Cas9 genome editing resulted in impaired mitochondrial function, increased superoxide presence, and detectable protein carbonylation. Inhibition of Complexes I and IV of the electron transport chain reduced neurite outgrowth in ZIP12 deficient cells. Transcriptional coactivator PGC-1α, mitochondrial superoxide dismutase (SOD2), and chemical antioxidants α-tocopherol, MitoTEMPO, and MitoQ restored neurite extension impaired by ZIP12 deficiency. Mutant forms of α-synuclein and tau linked to familial Parkinson's disease and frontotemporal dementia, respectively, reduced neurite outgrowth in cells deficient in ZIP12. Zinc and ZIP12 may confer resilience against neurological diseases or premature aging of the brain.
Collapse
Affiliation(s)
- Morgan D Strong
- Department of Nutritional Sciences, Oklahoma State University, Stillwater, OK, USA
| | - Matthew D Hart
- Department of Nutritional Sciences, Oklahoma State University, Stillwater, OK, USA
| | - Tony Z Tang
- Department of Nutritional Sciences, Oklahoma State University, Stillwater, OK, USA
| | - Babajide A Ojo
- Department of Nutritional Sciences, Oklahoma State University, Stillwater, OK, USA
| | - Lei Wu
- Department of Nutritional Sciences, Oklahoma State University, Stillwater, OK, USA
| | - Mariah R Nacke
- Department of Nutritional Sciences, Oklahoma State University, Stillwater, OK, USA
| | - Workneh T Agidew
- Department of Nutritional Sciences, Oklahoma State University, Stillwater, OK, USA
| | - Hong J Hwang
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK, USA
| | - Peter R Hoyt
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK, USA
| | - Ahmed Bettaieb
- Department of Nutrition, University of Tennessee, Knoxville, TN, USA
| | - Stephen L Clarke
- Department of Nutritional Sciences, Oklahoma State University, Stillwater, OK, USA
| | - Brenda J Smith
- Department of Nutritional Sciences, Oklahoma State University, Stillwater, OK, USA
| | - Barbara J Stoecker
- Department of Nutritional Sciences, Oklahoma State University, Stillwater, OK, USA
| | - Edralin A Lucas
- Department of Nutritional Sciences, Oklahoma State University, Stillwater, OK, USA
| | - Dingbo Lin
- Department of Nutritional Sciences, Oklahoma State University, Stillwater, OK, USA
| | - Winyoo Chowanadisai
- Department of Nutritional Sciences, Oklahoma State University, Stillwater, OK, USA
| |
Collapse
|
9
|
Zhao X, Li S, Gaur U, Zheng W. Artemisinin Improved Neuronal Functions in Alzheimer's Disease Animal Model 3xtg Mice and Neuronal Cells via Stimulating the ERK/CREB Signaling Pathway. Aging Dis 2020; 11:801-819. [PMID: 32765947 PMCID: PMC7390534 DOI: 10.14336/ad.2019.0813] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2019] [Accepted: 08/13/2019] [Indexed: 01/03/2023] Open
Abstract
The most common form of dementia is Alzheimer’s disease which is characterized by memory loss and cognitive disorders. The pathogenesis of Alzheimer’s disease is not known at present but toxicity of amyloid-beta is one of the central hypotheses. Amyloid-beta can stimulate the production of reactive oxygen species (ROS), cause oxidative stress, damage mitochondrial, cause inflammatory reactions and activate apoptosis related factors which lead to the neuronal death. In this study, we found that artemisinin, a first line antimalarial drug used in clinic for decades, improved the cognitive functions in Alzheimer’s disease animal model 3xTg mice. Further study showed that artemisinin reduced the deposition of amyloid-beta and tau protein, reduced the release of inflammation factors and apoptosis factors, and thereby reduced the neuronal cell death. Western blot assay showed that artemisinin stimulated the activation of ERK/CREB signaling pathway. Consistent with these results, artemisinin concentration-dependently promoted the survival of SH-SY5Y cell against toxicity of amyloid-beta protein 1-42 induced ROS accumulation, caspase activation and apoptosis. Artemisinin also stimulated the phosphorylation of ERK1/2 and CREB in SH-SY5Y cells in time and concentration-dependent manner. Inhibition of ERK/CREB pathway attenuated the protective effect of artemisinin. These data put together suggested that artemisinin has the potential to protect neuronal cells in vitro as well as in vivo animal model 3xTg mice via, at least in part, the activation of the ERK/CREB pathway. Our findings also strongly support the potential of artemisinin as a new multi-target drug that can be used for preventing and treating the Alzheimer’s disease.
Collapse
Affiliation(s)
- Xia Zhao
- Center of Reproduction, Development & Aging and Institute of Translation Medicine, Faculty of Health Sciences, University of Macau, Taipa, Macau, China
| | - Shuai Li
- Center of Reproduction, Development & Aging and Institute of Translation Medicine, Faculty of Health Sciences, University of Macau, Taipa, Macau, China
| | - Uma Gaur
- Center of Reproduction, Development & Aging and Institute of Translation Medicine, Faculty of Health Sciences, University of Macau, Taipa, Macau, China
| | - Wenhua Zheng
- Center of Reproduction, Development & Aging and Institute of Translation Medicine, Faculty of Health Sciences, University of Macau, Taipa, Macau, China
| |
Collapse
|
10
|
Tripathi MK, Rasheed MSU, Mishra AK, Patel DK, Singh MP. Silymarin Protects Against Impaired Autophagy Associated with 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine-Induced Parkinsonism. J Mol Neurosci 2019; 70:276-283. [PMID: 31732923 DOI: 10.1007/s12031-019-01431-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Accepted: 10/18/2019] [Indexed: 12/28/2022]
Abstract
1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) exacerbates mitochondrial impairment and α-synuclein expression leading to Parkinsonism. Impaired mitochondria and over-expressed α-synuclein are degraded and eliminated via macroautophagy and chaperone-mediated autophagy. Owing to multiple properties, silymarin protects from oxidative stress-mediated cellular injury. However, its effect on MPTP-induced changes in autophagy is not yet known. The study aimed to decipher the effect of silymarin on MPTP-induced changes in autophagy. Male mice (20-25 g) were treated with silymarin (intraperitoneally, daily, 40 mg/kg) for 2 weeks. On day 7, a few animals were also administered with MPTP (intraperitoneally, 20 mg/kg, 4 injections at 2-h interval) along with vehicles. Striatal dopamine content was determined. Western blot analysis was done to assess α-synuclein, beclin-1, sequestosome, phosphorylated 5' adenosine monophosphate-activated protein kinase (p-AMPK), lysosome-associated membrane protein-2 (LAMP-2), heat shock cognate-70 (Hsc-70), LAMP-2A, phosphorylated unc-51-like autophagy activating kinase (p-Ulk1), and phosphorylated mechanistic target of rapamycin (p-mTOR) levels in the nigrostriatal tissue. Silymarin rescued from MPTP-induced increase in beclin-1, sequestosome, p-AMPK, and p-Ulk1 and decrease in LAMP-2, p-mTOR, and LAMP-2A levels. Silymarin defended against MPTP-induced increase in α-synuclein and reduction in dopamine content. The results demonstrate that silymarin protects against MPTP-induced changes in autophagy leading to Parkinsonism.
Collapse
Affiliation(s)
- Manish Kumar Tripathi
- Toxicogenomics and Predictive Toxicology Laboratory, Systems Toxicology and Health Risk Assessment Group, CSIR-Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhawan, 31, Mahatma Gandhi Marg, Lucknow, Uttar Pradesh, 226001, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, 201002, India
| | - Mohd Sami Ur Rasheed
- Toxicogenomics and Predictive Toxicology Laboratory, Systems Toxicology and Health Risk Assessment Group, CSIR-Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhawan, 31, Mahatma Gandhi Marg, Lucknow, Uttar Pradesh, 226001, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, 201002, India
| | - Abhishek Kumar Mishra
- Toxicogenomics and Predictive Toxicology Laboratory, Systems Toxicology and Health Risk Assessment Group, CSIR-Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhawan, 31, Mahatma Gandhi Marg, Lucknow, Uttar Pradesh, 226001, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, 201002, India
| | - Devendra Kumar Patel
- Analytical Chemistry Laboratory, Regulatory Toxicology Group, CSIR-IITR, Vishvigyan Bhawan, 31, Mahatma Gandhi Marg, Lucknow, Uttar Pradesh, 226001, India
| | - Mahendra Pratap Singh
- Toxicogenomics and Predictive Toxicology Laboratory, Systems Toxicology and Health Risk Assessment Group, CSIR-Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhawan, 31, Mahatma Gandhi Marg, Lucknow, Uttar Pradesh, 226001, India. .,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, 201002, India.
| |
Collapse
|
11
|
Neuroprotective effects of acetyl-l-carnitine (ALC) in a chronic MPTP-induced Parkinson's disease mouse model: Endothelial and microglial effects. Neurosci Lett 2019; 703:86-95. [PMID: 30890473 DOI: 10.1016/j.neulet.2019.03.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 02/26/2019] [Accepted: 03/11/2019] [Indexed: 01/27/2023]
Abstract
Parkinson's disease (PD) is a progressive motor disease with clinical features emerging due to degeneration of dopaminergic neurons in the substantia nigra pars compacta (SNc), which project to the caudate putamen (CPu) where they release dopamine (DA). The current study investigated whether acetyl-l-carnitine (ALC) could ameliorate the pathology seen in an in vivoin vivo chronic 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced mouse model of PD. Four treatment groups were included: 1) CONTROL receiving probenecid (PROB; 250 mg/kg) only, 2) MPTP (25 mg/kg) + PROB, 3) MPTP + ALC (100 mg/kg), and 4) ALC alone. MPTP-induced losses in tyrosine hydroxylase and DA transporter immunoreactivity in the SNc and CPu were significantly reduced by ALC. HPLC data further suggests that decreases in CPu DA levels produced by MPTP were also attenuated by ALC. Additionally, microglial activation and astrocytic reactivity induced by MPTP were greatly reduced by ALC, indicating protection against neuroinflammation. Glucose transporter-1 and the tight junction proteins occludin and zonula occludins-1 were also protected from MPTP-induced down-regulation by ALC. Together, data suggest that in this model, ALC protects against MPTP-induced damage to endothelial cells and loss of DA neurons in the SNc and CPu, suggesting that ALC therapy may have the potential to slow or ameliorate the progression of PD pathology in a clinical setting.
Collapse
|
12
|
Xu SF, Zhang YH, Wang S, Pang ZQ, Fan YG, Li JY, Wang ZY, Guo C. Lactoferrin ameliorates dopaminergic neurodegeneration and motor deficits in MPTP-treated mice. Redox Biol 2018; 21:101090. [PMID: 30593976 PMCID: PMC6307097 DOI: 10.1016/j.redox.2018.101090] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 12/17/2018] [Accepted: 12/19/2018] [Indexed: 02/06/2023] Open
Abstract
Brain iron accumulation is common in patients with Parkinson's disease (PD). Iron chelators have been investigated for their ability to prevent neurodegenerative diseases with features of iron overload. Given the non-trivial side effects of classical iron chelators, lactoferrin (Lf), a multifunctional iron-binding globular glycoprotein, was screened to identify novel neuroprotective pathways against dopaminergic neuronal impairment. We found that Lf substantially ameliorated PD-like motor dysfunction in the subacute 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mouse model of PD. We further showed that Lf could alleviate MPTP-triggered apoptosis of DA neurons, neuroinflammation, and histological alterations. As expected, we also found that Lf suppressed MPTP-induced excessive iron accumulation and the upregulation of divalent metal transporter (DMT1) and transferrin receptor (TFR), which is the main intracellular iron regulation protein, and subsequently improved the activity of several antioxidant enzymes. We probed further and determined that the neuroprotection provided by Lf was involved in the upregulated levels of brain-derived neurotrophic factor (BDNF), hypoxia-inducible factor 1α (HIF-1α) and its downstream protein, accompanied by the activation of extracellular regulated protein kinases (ERK) and cAMP response element binding protein (CREB), as well as decreased phosphorylation of c-Jun N-terminal kinase (JNK) and mitogen activated protein kinase (MAPK)/P38 kinase in vitro and in vivo. Our findings suggest that Lf may be an alternative safe drug in ameliorating MPTP-induced brain abnormalities and movement disorder.
Collapse
Affiliation(s)
- Shuang-Feng Xu
- College of Life and Health Sciences, Northeastern University, No.195, Chuangxin Road, Hunnan District, Shenyang 110169, China
| | - Yan-Hui Zhang
- College of Life and Health Sciences, Northeastern University, No.195, Chuangxin Road, Hunnan District, Shenyang 110169, China
| | - Shan Wang
- College of Life and Health Sciences, Northeastern University, No.195, Chuangxin Road, Hunnan District, Shenyang 110169, China
| | - Zhong-Qiu Pang
- College of Life and Health Sciences, Northeastern University, No.195, Chuangxin Road, Hunnan District, Shenyang 110169, China
| | - Yong-Gang Fan
- College of Life and Health Sciences, Northeastern University, No.195, Chuangxin Road, Hunnan District, Shenyang 110169, China
| | - Jia-Yi Li
- College of Life and Health Sciences, Northeastern University, No.195, Chuangxin Road, Hunnan District, Shenyang 110169, China; Institute of Health Sciences, Key Laboratory of Medical Cell Biology of Ministry of Education, China Medical University, Shenyang 110122, China; Neural Plasticity and Repair Unit, Wallenberg Neuroscience Center, Department of Experimental Medical Science, Lund University, BMC A10, 22184 Lund, Sweden
| | - Zhan-You Wang
- College of Life and Health Sciences, Northeastern University, No.195, Chuangxin Road, Hunnan District, Shenyang 110169, China; Institute of Health Sciences, Key Laboratory of Medical Cell Biology of Ministry of Education, China Medical University, Shenyang 110122, China.
| | - Chuang Guo
- College of Life and Health Sciences, Northeastern University, No.195, Chuangxin Road, Hunnan District, Shenyang 110169, China.
| |
Collapse
|
13
|
Lantz SM, Rosas-Hernandez H, Cuevas E, Robinson B, Rice KC, Fantegrossi WE, Imam SZ, Paule MG, Ali SF. Monoaminergic toxicity induced by cathinone phthalimide: An in vitro study. Neurosci Lett 2017; 655:76-81. [PMID: 28684237 DOI: 10.1016/j.neulet.2017.06.059] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 06/21/2017] [Accepted: 06/30/2017] [Indexed: 12/26/2022]
Abstract
Bath salts, or synthetic cathinones, have cocaine-like or amphetamine-like properties and induce psychoactive effects via their capacity to modulate serotonin (5-HT) and dopamine (DA). Structurally distinct synthetic cathinones are continuously being generated to skirt existing drug laws. One example of these modified compounds is cathinone phthalimide (CP), which has already appeared on the global market. The lack of toxicological studies on the effects of CP on monoaminergic systems led to the development of the present study in order to generate an acute toxicity profile for CP, and to clarify whether it primarily affects both dopamine and serotonin, like the synthetic cathinones mephedrone and methylone, or primarily affects dopamine, like 3, 4-methylenedioxypyrovalerone (MDPV). For the first time, the toxicity profile of CP (10μM-1000μM) is reported. In pheochromocytoma cells, exposure to CP induced cell death, and altered mitochondrial function, as well as intracellular DA and 5-HT levels; at the same time, reduced glutathione (GSH) levels remained unaffected. This seems to indicate that CP functions like mephedrone or methylone. The role of CP metabolites, the effect of CP induced hyperthermia on neurotoxicity, and its ability to traverse the blood-brain barrier warrant further consideration.
Collapse
Affiliation(s)
- Susan M Lantz
- Neurochemistry Laboratory, Division of Neurotoxicology, National Center for Toxicological Research/FDA, 3900 NCTR Rd, HFT-132, Jefferson, AR, 72079, United States.
| | - Hector Rosas-Hernandez
- Neurochemistry Laboratory, Division of Neurotoxicology, National Center for Toxicological Research/FDA, 3900 NCTR Rd, HFT-132, Jefferson, AR, 72079, United States.
| | - Elvis Cuevas
- Neurochemistry Laboratory, Division of Neurotoxicology, National Center for Toxicological Research/FDA, 3900 NCTR Rd, HFT-132, Jefferson, AR, 72079, United States.
| | - Bonnie Robinson
- Neurochemistry Laboratory, Division of Neurotoxicology, National Center for Toxicological Research/FDA, 3900 NCTR Rd, HFT-132, Jefferson, AR, 72079, United States.
| | - Kenner C Rice
- Drug Design and Synthesis Section, Molecular Targets and Medications Discovery Branch, NIDA/NIAAA 9800 Medical Center Drive Rm 228A, MSC-3373, Bethesda, MD, 20892, United States.
| | - William E Fantegrossi
- Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States.
| | - Syed Z Imam
- Neurochemistry Laboratory, Division of Neurotoxicology, National Center for Toxicological Research/FDA, 3900 NCTR Rd, HFT-132, Jefferson, AR, 72079, United States.
| | - Merle G Paule
- Neurochemistry Laboratory, Division of Neurotoxicology, National Center for Toxicological Research/FDA, 3900 NCTR Rd, HFT-132, Jefferson, AR, 72079, United States.
| | - Syed F Ali
- Neurochemistry Laboratory, Division of Neurotoxicology, National Center for Toxicological Research/FDA, 3900 NCTR Rd, HFT-132, Jefferson, AR, 72079, United States.
| |
Collapse
|
14
|
|
15
|
Abnormalities of Mitochondrial Dynamics in Neurodegenerative Diseases. Antioxidants (Basel) 2017; 6:antiox6020025. [PMID: 28379197 PMCID: PMC5488005 DOI: 10.3390/antiox6020025] [Citation(s) in RCA: 141] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 03/24/2017] [Accepted: 04/03/2017] [Indexed: 12/14/2022] Open
Abstract
Neurodegenerative diseases are incurable and devastating neurological disorders characterized by the progressive loss of the structure and function of neurons in the central nervous system or peripheral nervous system. Mitochondria, organelles found in most eukaryotic cells, are essential for neuronal survival and are involved in a number of neuronal functions. Mitochondrial dysfunction has long been demonstrated as a common prominent early pathological feature of a variety of common neurodegenerative diseases, including Alzheimer’s disease (AD), Parkinson’s disease (PD), amyotrophic lateral sclerosis (ALS), and Huntington’s disease (HD). Mitochondria are highly dynamic organelles that undergo continuous fusion, fission, and transport, the processes of which not only control mitochondrial morphology and number but also regulate mitochondrial function and location. The importance of mitochondrial dynamics in the pathogenesis of neurodegenerative diseases has been increasingly unraveled after the identification of several key fusion and fission regulators such as Drp1, OPA1, and mitofusins. In this review, after a brief discussion of molecular mechanisms regulating mitochondrial fusion, fission, distribution, and trafficking, as well as the important role of mitochondrial dynamics for neuronal function, we review previous and the most recent studies about mitochondrial dynamic abnormalities observed in various major neurodegenerative diseases and discuss the possibility of targeting mitochondrial dynamics as a likely novel therapeutic strategy for neurodegenerative diseases.
Collapse
|
16
|
Cunha MP, Pazini FL, Lieberknecht V, Budni J, Oliveira Á, Rosa JM, Mancini G, Mazzardo L, Colla AR, Leite MC, Santos ARS, Martins DF, de Bem AF, Gonçalves CAS, Farina M, Rodrigues ALS. MPP +-Lesioned Mice: an Experimental Model of Motor, Emotional, Memory/Learning, and Striatal Neurochemical Dysfunctions. Mol Neurobiol 2016; 54:6356-6377. [PMID: 27722926 DOI: 10.1007/s12035-016-0147-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Accepted: 09/19/2016] [Indexed: 12/13/2022]
Abstract
The neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) induces motor and nonmotor dysfunctions resembling Parkinson's disease (PD); however, studies investigating the effects of 1-methyl-4-phenylpyridinium (MPP+), an active oxidative product of MPTP, are scarce. This study investigated the behavioral and striatal neurochemical changes (related to oxidative damage, glial markers, and neurotrophic factors) 24 h after intracerebroventricular administration of MPP+ (1.8-18 μg/mouse) in C57BL6 mice. MPP+ administration at high dose (18 μg/mouse) altered motor parameters, since it increased the latency to leave the first quadrant and reduced crossing, rearing, and grooming responses in the open-field test and decreased rotarod latency time. MPP+ administration at low dose (1.8 μg/mouse) caused specific nonmotor dysfunctions as it produced a depressive-like effect in the forced swim test and tail suspension test, loss of motivational and self-care behavior in the splash test, anxiety-like effect in the elevated plus maze test, and short-term memory deficit in the step-down inhibitory avoidance task, without altering ambulation. MPP+ at doses of 1.8-18 μg/mouse increased tyrosine hydroxylase (TH) immunocontent and at 18 μg/mouse increased α-synuclein and decreased parkin immunocontent. The astrocytic calcium-binding protein S100B and glial fibrillary acidic protein (GFAP)/S100B ratio was decreased following MPP+ administration (18 μg/mouse). At this highest dose, MPP+ increased the ionized calcium-binding adapter molecule 1 (Iba-1) immunocontent, suggesting microglial activation. Also, MPP+ at a dose of 18 μg/mouse increased thiobarbituric acid reactive substances (TBARS) and glutathione (GSH) levels and increased glutathione peroxidase (GPx) and hemeoxygenase-1 (HO-1) immunocontent, suggesting a significant role for oxidative stress in the MPP+-induced striatal damage. MPP+ (18 μg/mouse) also increased striatal fibroblast growth factor 2 (FGF-2) and brain-derived neurotrophic factor (BDNF) levels. Moreover, MPP+ decreased tropomyosin receptor kinase B (TrkB) immunocontent. Finally, MPP+ (1.8-18 μg/mouse) increased serum corticosterone levels and did not alter acetylcholinesterase (AChE) activity in the striatum but increased it in cerebral cortex and hippocampus. Collectively, these results indicate that MPP+ administration at low doses may be used as a model of emotional and memory/learning behavioral deficit related to PD and that MPP+ administration at high dose could be useful for analysis of striatal dysfunctions associated with motor deficits in PD.
Collapse
Affiliation(s)
- Mauricio P Cunha
- Department of Biochemistry, Center of Biological Sciences, Universidade Federal de Santa Catarina, Florianópolis, SC, 88040-900, Brazil.
| | - Francis L Pazini
- Department of Biochemistry, Center of Biological Sciences, Universidade Federal de Santa Catarina, Florianópolis, SC, 88040-900, Brazil
| | - Vicente Lieberknecht
- Department of Biochemistry, Center of Biological Sciences, Universidade Federal de Santa Catarina, Florianópolis, SC, 88040-900, Brazil
| | - Josiane Budni
- Laboratory of Neurosciences, National Institute for Translational Medicine, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil
| | - Ágatha Oliveira
- Department of Biochemistry, Institute of Chemistry, Universidade de São Paulo, São Paulo, SP, 05508-900, Brazil
| | - Júlia M Rosa
- Department of Biochemistry, Center of Biological Sciences, Universidade Federal de Santa Catarina, Florianópolis, SC, 88040-900, Brazil
| | - Gianni Mancini
- Department of Biochemistry, Center of Biological Sciences, Universidade Federal de Santa Catarina, Florianópolis, SC, 88040-900, Brazil
| | - Leidiane Mazzardo
- Department of Morphological Sciences, Center of Biological Science, Universidade Federal de Santa Catarina, Florianópolis, SC, 88040-900, Brazil
| | - André R Colla
- Centro Universitário Municipal de São José, São José, SC, Brazil
| | - Marina C Leite
- Department of Biochemistry, Institute of Basic Health Science, Universidade Federal do Rio Grande do Sul, Ramiro Barcelos, 2600-Anexo, Porto Alegre, Rio Grande do Sul, 90035-003, Brazil
| | - Adair R S Santos
- Department of Physiological Sciences, Center of Biological Science, Universidade Federal de Santa Catarina, Florianópolis, SC, 88040-900, Brazil
| | - Daniel F Martins
- Graduate Program in Health Sciences, Universidade do Sul de Santa Catarina, Pedra Branca, Palhoça, SC, 88137-270, Brazil
| | - Andreza F de Bem
- Department of Biochemistry, Center of Biological Sciences, Universidade Federal de Santa Catarina, Florianópolis, SC, 88040-900, Brazil
| | - Carlos Alberto S Gonçalves
- Department of Biochemistry, Institute of Basic Health Science, Universidade Federal do Rio Grande do Sul, Ramiro Barcelos, 2600-Anexo, Porto Alegre, Rio Grande do Sul, 90035-003, Brazil
| | - Marcelo Farina
- Department of Biochemistry, Center of Biological Sciences, Universidade Federal de Santa Catarina, Florianópolis, SC, 88040-900, Brazil
| | - Ana Lúcia S Rodrigues
- Department of Biochemistry, Center of Biological Sciences, Universidade Federal de Santa Catarina, Florianópolis, SC, 88040-900, Brazil
| |
Collapse
|
17
|
Ray A, Sehgal N, Karunakaran S, Rangarajan G, Ravindranath V. MPTP activates ASK1-p38 MAPK signaling pathway through TNF-dependent Trx1 oxidation in parkinsonism mouse model. Free Radic Biol Med 2015; 87:312-25. [PMID: 26164633 DOI: 10.1016/j.freeradbiomed.2015.06.041] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Revised: 06/16/2015] [Accepted: 06/28/2015] [Indexed: 10/23/2022]
Abstract
Activation of apoptosis signal-regulating kinase 1 (ASK1)-p38 MAPK death signaling cascade is implicated in the death of dopaminergic neurons in substantia nigra in Parkinson's disease (PD). We investigated upstream activators of ASK1 using an MPTP mouse model of parkinsonism and assessed the temporal cascade of death signaling in ventral midbrain (VMB) and striatum (ST). MPTP selectively activated ASK1 and downstream p38 MAPK in a time-dependent manner in VMB alone. This occurred through selective protein thiol oxidation of the redox-sensitive thiol disulfide oxidoreductase, thioredoxin (Trx1), resulting in release of its inhibitory association with ASK1, while glutathione-S-transferase µ 1 (GSTM1) remained in reduced form in association with ASK1. Levels of tumor necrosis factor (TNF), a known activator of ASK1, increased early after MPTP in VMB. Protein covariation network analysis (PCNA) using protein states as nodes revealed TNF to be an important node regulating the ASK1 signaling cascade. In confirmation, blocking MPTP-mediated TNF signaling through intrathecal administration of TNF-neutralizing antibody prevented Trx1 oxidation and downstream ASK1-p38 MAPK activation. Averting an early increase in TNF, which leads to protein thiol oxidation resulting in activation of ASK1-p38 signaling, may be critical for neuroprotection in PD. Importantly, network analysis can help in understanding the cause/effect relationship within protein networks in complex disease states.
Collapse
Affiliation(s)
- Ajit Ray
- National Brain Research Centre, Nainwal Mode, Manesar-122051, India; Centre for Neuroscience, Indian Institute of Science, Bangalore 560012, India
| | - Neha Sehgal
- National Brain Research Centre, Nainwal Mode, Manesar-122051, India
| | | | - Govindan Rangarajan
- Department of Mathematics, Indian Institute of Science, Bangalore 560012, India
| | | |
Collapse
|
18
|
Yoon SY, Oh YJ. Glucose Levels in Culture Medium Determine Cell Death Mode in MPP(+)-treated Dopaminergic Neuronal Cells. Exp Neurobiol 2015; 24:197-205. [PMID: 26412968 PMCID: PMC4580746 DOI: 10.5607/en.2015.24.3.197] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 08/16/2015] [Accepted: 08/17/2015] [Indexed: 11/19/2022] Open
Abstract
We previously demonstrated that 1-methyl-4-phenylpyridinium (MPP(+)) causes caspase-independent, non-apoptotic death of dopaminergic (DA) neuronal cells. Here, we specifically examined whether change of glucose concentration in culture medium may play a role for determining cell death modes of DA neurons following MPP(+) treatment. By incubating MN9D cells in medium containing varying concentrations of glucose (5~35 mM), we found that cells underwent a distinct cell death as determined by morphological and biochemical criteria. At 5~10 mM glucose concentration (low glucose levels), MPP(+) induced typical of the apoptotic dell death accompanied with caspase activation and DNA fragmentation as well as cell shrinkage. In contrast, MN9D cells cultivated in medium containing more than 17.5 mM (high glucose levels) did not demonstrate any of these changes. Subsequently, we observed that MPP(+) at low glucose levels but not high glucose levels led to ROS generation and subsequent JNK activation. Therefore, MPP(+)-induced cell death only at low glucose levels was significantly ameliorated following co-treatment with ROS scavenger, caspase inhibitor or JNK inhibitor. We basically confirmed the quite similar pattern of cell death in primary cultures of DA neurons. Taken together, our results suggest that a biochemically distinct cell death mode is recruited by MPP(+) depending on extracellular glucose levels.
Collapse
Affiliation(s)
- So-Young Yoon
- Department of Systems Biology, Yonsei University College of Life Science and Biotechnology, Seoul 03722, Korea
| | - Young J Oh
- Department of Systems Biology, Yonsei University College of Life Science and Biotechnology, Seoul 03722, Korea
| |
Collapse
|
19
|
Decreased expression of organic cation transporters, Oct1 and Oct2, in brain microvessels and its implication to MPTP-induced dopaminergic toxicity in aged mice. J Cereb Blood Flow Metab 2015; 35:37-47. [PMID: 25248837 PMCID: PMC4294392 DOI: 10.1038/jcbfm.2014.162] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Revised: 08/25/2014] [Accepted: 08/26/2014] [Indexed: 12/15/2022]
Abstract
This study was to investigate the influence of age on the expression of organic cation transporters (OCTs) that belong to the SLC22 family in brain microvessels (BMVs) and its implications for 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced dopaminergic toxicity in mice. Here, we showed that Oct1 and Oct2, but not Oct3, mRNAs were detected and enriched (compared with cerebral cortex) in BMVs of C57BL/6 (B6) mice using reverse transcription-quantitative PCR (RT-qPCR), and immunofluorescence analysis further revealed that Oct1 and Oct2 proteins were colocalized with endothelial markers. Both the mRNA and protein levels of Oct1 and Oct2 were reduced in aged mice. After an intraperitoneal administration of MPTP, brain extracellular levels of MPTP and 1-methyl-4-phenyl-pyridinium (MPP(+)) were much lower in aged mice and in Oct1/2(-/-) mice compared with younger mice and wild-type control mice, respectively. Knockout of Oct1/Oct2 protected Oct1/2(-/-) mice from MPTP-induced neurotoxicity, whereas the loss of tyrosine hydroxylase (TH)-positive neurons was slightly greater in aged than in younger mice. However, intrastriatal infusion of low-dose MPTP caused more severe dopaminergic toxicity in the substantia nigra of both aged mice and Oct1/2(-/-) mice. These findings show that age-dependent downregulation or knockout of Oct1/Oct2 in BMVs may reduce the transport of MPTP, which, in part, affects its dopaminergic toxicity.
Collapse
|
20
|
Meredith GE, Rademacher DJ. MPTP mouse models of Parkinson's disease: an update. JOURNAL OF PARKINSONS DISEASE 2014; 1:19-33. [PMID: 23275799 DOI: 10.3233/jpd-2011-11023] [Citation(s) in RCA: 288] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Among the most widely used models of Parkinson's disease (PD) are those that employ toxins, especially 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Depending on the protocol used, MPTP yields large variations in nigral cell loss, striatal dopamine loss and behavioral deficits. Motor deficits do not fully replicate those seen in PD. Nonetheless, MPTP mouse models mimic many aspects of the disease and are therefore important tools for understanding PD. In this review, we will discuss the ability of MPTP mouse models to replicate the pathophysiology of PD, the mechanisms of MPTP-induced neurotoxicity, strain differences in susceptibility to MPTP, and the models' roles in testing therapeutic approaches.
Collapse
Affiliation(s)
- Gloria E Meredith
- Department of Pharmaceutical Sciences, College of Pharmacy, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois 60064, USA.
| | | |
Collapse
|
21
|
Kim YD, Lantz-McPeak SM, Ali SF, Kleinman MT, Choi YS, Kim H. Effects of ultrafine diesel exhaust particles on oxidative stress generation and dopamine metabolism in PC-12 cells. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2014; 37:954-959. [PMID: 24705343 DOI: 10.1016/j.etap.2014.03.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2013] [Revised: 03/12/2014] [Accepted: 03/13/2014] [Indexed: 06/03/2023]
Abstract
A major constituent of urban air pollution is diesel exhaust, a complex mixture of gases, chemicals, and particles. Recent evidence suggests that exposure to air pollution can increase the risk of a fatal stroke, cause cerebrovascular damage, and induce neuroinflammation and oxidative stress that may trigger neurodegenerative diseases, such as Parkinson's disease. The specific aim of this study was to determine whether ultrafine diesel exhaust particles (DEPs), the particle component of exhaust from diesel engines, can induce oxidative stress and effect dopamine metabolism in PC-12 cells. After 24 h exposure to DEPs of 200 nm or smaller, cell viability, ROS and nitric oxide (NO(2)) generation, and levels of dopamine (DA) and its metabolites, (dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA)), were evaluated. Results indicated cell viability was not significantly changed by DEP exposure. However, ROS showed dramatic dose-dependent changes after DEP exposure (2.4 fold increase compared to control at 200 μg/mL). NO(2) levels were also dose-dependently increased after DEP exposure. Although not in a dose-dependent manner, upon DEP exposure, intracellular DA levels were increased while DOPAC and HVA levels decreased when compared to control. Results suggest that ultrafine DEPs lead to dopamine accumulation in the cytoplasm of PC-12 cells, possibly contributing to ROS formation. Further studies are warranted to elucidate this mechanism.
Collapse
Affiliation(s)
- Yong-Dae Kim
- Department of Preventive Medicine, College of Medicine and Medical Research Institute, Chungbuk National University, Cheongju, Chungbuk 361-763, Republic of Korea.
| | - Susan M Lantz-McPeak
- Neurochemistry Laboratory, Division of Neurotoxicology, National Center of Toxicological Research/Food and Drug Administration, 3900 NCTR Road, Jefferson, AR, United States
| | - Syed F Ali
- Neurochemistry Laboratory, Division of Neurotoxicology, National Center of Toxicological Research/Food and Drug Administration, 3900 NCTR Road, Jefferson, AR, United States.
| | - Michael T Kleinman
- Department of Medicine, University of California at Irvine, 19182 Jamboree Rd. FRF 100, Irvine, CA, United States
| | - Young-Sook Choi
- Department of Preventive Medicine, College of Medicine and Medical Research Institute, Chungbuk National University, Cheongju, Chungbuk 361-763, Republic of Korea
| | - Heon Kim
- Department of Preventive Medicine, College of Medicine and Medical Research Institute, Chungbuk National University, Cheongju, Chungbuk 361-763, Republic of Korea
| |
Collapse
|
22
|
Salam S, Ansari A, Amon S, Rezai P, Selvaganapathy PR, Mishra RK, Gupta BP. A microfluidic phenotype analysis system reveals function of sensory and dopaminergic neuron signaling in C. elegans electrotactic swimming behavior. WORM 2013; 2:e24558. [PMID: 24058875 PMCID: PMC3704449 DOI: 10.4161/worm.24558] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2013] [Revised: 04/02/2013] [Accepted: 04/04/2013] [Indexed: 12/21/2022]
Abstract
The nematode (worm) C. elegans is a leading multicellular animal model to study neuronal-basis of behavior. Worms respond to a wide range of stimuli and exhibit characteristic movement patterns. Here we describe the use of a microfluidics setup to probe neuronal activity that relies on the innate response of C. elegans to swim toward the cathode in the presence of a DC electric field (termed "electrotaxis"). Using this setup, we examined mutants affecting sensory and dopaminergic neurons and found that their electrotactic responses were defective. Such animals moved with reduced speed (35-80% slower than controls) with intermittent pauses, abnormal turning and slower body bends. A similar phenotype was observed in worms treated with neurotoxins 6-OHDA (6- hydroxy dopamine), MPTP (1-methyl 4-phenyl 1,2,3,6-tetrahydropyridine) and rotenone (20-60% slower). We also found that neurotoxin effects could be suppressed by pre-exposing worms to a known neuroprotective compound acetaminophen. Collectively, these results show that microfluidic electrotaxis can identify alterations in dopamine and amphid neuronal signaling based on swimming responses of C. elegans. Further characterization has revealed that the electrotactic swimming response is highly sensitive and reliable in detecting neuronal abnormalities. Thus, our microfluidics setup could be used to dissect neuronal function and toxin-induced neurodegeneration. Among other applications, the setup promises to facilitate genetic and chemical screenings to identify factors that mediate neuronal signaling and neuroprotection.
Collapse
Affiliation(s)
- Sangeena Salam
- Department of Biology; McMaster University; Hamilton, ON Canada
| | - Ata Ansari
- Department of Biology; McMaster University; Hamilton, ON Canada
- Department of Psychiatry and Behavioral Neuroscience; McMaster University; Hamilton, ON Canada
| | - Siavash Amon
- Department of Biology; McMaster University; Hamilton, ON Canada
| | - Pouya Rezai
- Department of Mechanical Engineering; McMaster University; Hamilton, ON Canada
| | | | - Ram K. Mishra
- Department of Psychiatry and Behavioral Neuroscience; McMaster University; Hamilton, ON Canada
| | | |
Collapse
|
23
|
Koppula S, Kumar H, More SV, Lim HW, Hong SM, Choi DK. Recent updates in redox regulation and free radical scavenging effects by herbal products in experimental models of Parkinson's disease. Molecules 2012; 17:11391-420. [PMID: 23014498 PMCID: PMC6268813 DOI: 10.3390/molecules171011391] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Revised: 09/12/2012] [Accepted: 09/21/2012] [Indexed: 11/16/2022] Open
Abstract
Parkinson’s disease (PD) is a complex multifactorial disease marked by extensive neuropathology in the brain with selective yet prominent and progressive loss of mid-brain dopaminergic neurons. The etiological factors involved in the development of PD are still elusive, but oxidative stress arising when reactive oxygen species (ROS) exceed amounts required for normal redox signaling is considered one of the major factors. ROS cause oxidative damage to proteins, lipids, and DNA and are one of the most prominent factors related to neurodegeneration. Pre-clinical and clinical studies clearly demonstrate the effectiveness of oxidative stress in the pathogenesis of PD. Therefore, regulation of redox signaling and inhibiting excess ROS would contribute greatly not only to extend longevity but also to ameliorate the progression of dopaminergic cell death seen in patients with PD. Several herbal products are beneficial for maintaining nerve cell function and for treating various neurodegenerative disorders by reducing oxidative stress. Here, we summarize the recent knowledge concerning promising herbs that have shown significant beneficial effects based on regulation of redox status and ROS inhibition in toxin-induced PD models.
Collapse
Affiliation(s)
- Sushruta Koppula
- Authors to whom correspondence should be addressed; (S.K.); (D.-K.C.); Tel.: +82-43-840-3610 (D.-K.C.); Fax: +82-43-840-3872 (D.-K.C.)
| | | | | | | | | | - Dong-Kug Choi
- Authors to whom correspondence should be addressed; (S.K.); (D.-K.C.); Tel.: +82-43-840-3610 (D.-K.C.); Fax: +82-43-840-3872 (D.-K.C.)
| |
Collapse
|
24
|
Alexander GE. Biology of Parkinson's disease: pathogenesis and pathophysiology of a multisystem neurodegenerative disorder. DIALOGUES IN CLINICAL NEUROSCIENCE 2012. [PMID: 22033559 PMCID: PMC3181806 DOI: 10.31887/dcns.2004.6.3/galexander] [Citation(s) in RCA: 263] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Parkinson's disease (PD) is the second most common movement disorder. The characteristic motor impairments - bradykinesia, rigidity, and resting tremor - result from degenerative loss of midbrain dopamine (DA) neurons in the substantia nigra, and are responsive to symptomatic treatment with dopaminergic medications and functional neurosurgery. PD is also the second most common neurodegenerative disorder. Viewed from this perspective, PD is a disorder of multiple functional systems, not simply the motor system, and of multiple neurotransmitter systems, not merely that of DA. The characteristic pathology - intraneuronal Lewy body inclusions and reduced numbers of surviving neurons - is similar in each of the targeted neuron groups, suggesting a common neurodegenerative process. Pathological and experimental studies indicate that oxidative stress, proteolytic stress, and inflammation figure prominently in the pathogenesis of PD. Yet, whether any of these mechanisms plays a causal role in human PD is unknown, because to date we have no proven neuroprotective therapies that slow or reverse disease progression in patients with PD. We are beginning to understand the pathophysiology of motor dysfunction in PD, but its etiopathogenesis as a neurodegenerative disorder remains poorly understood.
Collapse
Affiliation(s)
- Garrett E Alexander
- Department of Neurology, Emory University School of Medicine, Atlanta, Ga, USA
| |
Collapse
|
25
|
Abstract
Many neurodegenerative diseases demonstrate abnormal mitochondrial morphology and biochemical dysfunction. Alterations are often systemic rather than brain-limited. Mitochondrial dysfunction may arise as a consequence of abnormal mitochondrial DNA, mutated nuclear proteins that interact directly or indirectly with mitochondria, or through unknown causes. In most cases it is unclear where mitochondria sit in relation to the overall disease cascades that ultimately causes neuronal dysfunction and death, and there is still controversy regarding the question of whether mitochondrial dysfunction is a necessary step in neurodegeneration. In this chapter we highlight and catalogue mitochondrial perturbations in some of the major neurodegenerative diseases including Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), and Huntington's disease (HD). We consider data that suggest mitochondria may be critically involved in neurodegenerative disease neurodegeneration cascades.
Collapse
Affiliation(s)
- E Lezi
- Department of Neurology, University of Kansas School of Medicine, Kansas City, KS 66209, USA.
| | | |
Collapse
|
26
|
The parkinsonian mimetic, MPP+, specifically impairs mitochondrial transport in dopamine axons. J Neurosci 2011; 31:7212-21. [PMID: 21562285 DOI: 10.1523/jneurosci.0711-11.2011] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Impaired axonal transport may play a key role in Parkinson's disease. To test this notion, a microchamber system was adapted to segregate axons from cell bodies using green fluorescent protein-labeled mouse dopamine (DA) neurons. Transport was examined in axons challenged with the DA neurotoxin, 1-methyl-4-phenylpyridinium ion (MPP+). MPP+ rapidly reduced overall mitochondrial motility in DA axons; among motile mitochondria, anterograde transport was slower yet retrograde transport was increased. Transport effects were specific for DA mitochondria, which were smaller and transported more slowly than their non-DA counterparts. MPP+ did not affect synaptophysin-tagged vesicles or any other measureable moving particle. Toxin effects on DA mitochondria were not dependent upon ATP, calcium, free radical species, JNK, or caspase3/PKC pathways but were completely blocked by the thiol-anti-oxidant N-acetyl-cysteine or membrane-permeable glutathione. Since these drugs also rescued processes from degeneration, these findings emphasize the need to develop therapeutics aimed at axons as well as cell bodies to preserve "normal" circuitry and function as long as possible.
Collapse
|
27
|
Malina HZ. System in biology leading to cell pathology: stable protein-protein interactions after covalent modifications by small molecules or in transgenic cells. J Biomed Sci 2011; 18:7. [PMID: 21247434 PMCID: PMC3036603 DOI: 10.1186/1423-0127-18-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Accepted: 01/19/2011] [Indexed: 11/30/2022] Open
Abstract
Background The physiological processes in the cell are regulated by reversible, electrostatic protein-protein interactions. Apoptosis is such a regulated process, which is critically important in tissue homeostasis and development and leads to complete disintegration of the cell. Pathological apoptosis, a process similar to apoptosis, is associated with aging and infection. The current study shows that pathological apoptosis is a process caused by the covalent interactions between the signaling proteins, and a characteristic of this pathological network is the covalent binding of calmodulin to regulatory sequences. Results Small molecules able to bind covalently to the amino group of lysine, histidine, arginine, or glutamine modify the regulatory sequences of the proteins. The present study analyzed the interaction of calmodulin with the BH3 sequence of Bax, and the calmodulin-binding sequence of myristoylated alanine-rich C-kinase substrate in the presence of xanthurenic acid in primary retinal epithelium cell cultures and murine epithelial fibroblast cell lines transformed with SV40 (wild type [WT], Bid knockout [Bid-/-], and Bax-/-/Bak-/- double knockout [DKO]). Cell death was observed to be associated with the covalent binding of calmodulin, in parallel, to the regulatory sequences of proteins. Xanthurenic acid is known to activate caspase-3 in primary cell cultures, and the results showed that this activation is also observed in WT and Bid-/- cells, but not in DKO cells. However, DKO cells were not protected against death, but high rates of cell death occurred by detachment. Conclusions The results showed that small molecules modify the basic amino acids in the regulatory sequences of proteins leading to covalent interactions between the modified sequences (e.g., calmodulin to calmodulin-binding sites). The formation of these polymers (aggregates) leads to an unregulated and, consequently, pathological protein network. The results suggest a mechanism for the involvement of small molecules in disease development. In the knockout cells, incorrect interactions between proteins were observed without the protein modification by small molecules, indicating the abnormality of the protein network in the transgenic system. The irreversible protein-protein interactions lead to protein aggregation and cell degeneration, which are observed in all aging-associated diseases.
Collapse
Affiliation(s)
- Halina Z Malina
- MalinaLab-Axanton, Tiefenaustr.110, CH-3004 Bern, Switzerland.
| |
Collapse
|
28
|
Schnackenberg B, Saini U, Robinson B, Ali S, Patterson T. An acute dose of gamma-hydroxybutyric acid alters gene expression in multiple mouse brain regions. Neuroscience 2010; 170:523-41. [DOI: 10.1016/j.neuroscience.2010.06.049] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2010] [Revised: 06/04/2010] [Accepted: 06/21/2010] [Indexed: 10/19/2022]
|
29
|
Liu J, Wang MW, Gu P, Ma QY, Wang YY, Geng Y, Yuan ZY, Cui DS, Zhang ZX, Ma L, Zhang BH, Zhou MG, Zhu AP. Microglial activation and age-related dopaminergic neurodegeneration in MPTP-treated SAMP8 mice. Brain Res 2010; 1345:213-20. [DOI: 10.1016/j.brainres.2010.05.043] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2010] [Revised: 05/10/2010] [Accepted: 05/11/2010] [Indexed: 11/26/2022]
|
30
|
Macrophage-mediated GDNF delivery protects against dopaminergic neurodegeneration: a therapeutic strategy for Parkinson's disease. Mol Ther 2010; 18:1536-44. [PMID: 20531393 DOI: 10.1038/mt.2010.107] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Glial cell line-derived neurotrophic factor (GDNF) has emerged as the most potent neuroprotective agent tested in experimental models for the treatment of Parkinson's disease (PD). However, its use is hindered by difficulties in delivery to the brain due to the presence of the blood-brain barrier (BBB). In order to circumvent this problem, we took advantage of the fact that bone marrow stem cell-derived macrophages are able to pass the BBB and home to sites of neuronal degeneration. Here, we report the development of a method for brain delivery of GDNF by genetically modified macrophages. Bone marrow stem cells were transduced ex vivo with lentivirus expressing a GDNF gene driven by a synthetic macrophage-specific promoter and then transplanted into recipient mice. Eight weeks after transplantation, the mice were injected with the neurotoxin, MPTP, for 7 days to induce dopaminergic neurodegeneration. Macrophage-mediated GDNF treatment dramatically ameliorated MPTP-induced degeneration of tyrosine hydroxylase (TH)-positive neurons of the substantia nigra and TH(+) terminals in the striatum, stimulated axon regeneration, and reversed hypoactivity in the open field test. These results indicate that macrophage-mediated GDNF delivery is a promising strategy for developing a neuroprotective therapy for PD.
Collapse
|
31
|
Masoud A, Kiran R, Sandhir R. Impaired mitochondrial functions in organophosphate induced delayed neuropathy in rats. Cell Mol Neurobiol 2010; 29:1245-55. [PMID: 19517227 DOI: 10.1007/s10571-009-9420-4] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2009] [Accepted: 05/22/2009] [Indexed: 12/15/2022]
Abstract
Acute exposure to organophosphates induces a delayed neurodegenerative condition known as organophosphate-induced delayed neuropathy (OPIDN). The mechanism of OPIDN has not been fully understood as it does not involve cholinergic crisis. The present study has been designed to evaluate the role of mitochondrial dysfunctions in the development of OPIDN. OPIDN was induced in rats by administering acute dose of monocrotophos (MCP, 20 mg/kg body weight, orally) or dichlorvos (DDVP, 200 mg/kg body weight, subcutaneously), 15-20 min after treatment with antidotes [atropine (20 mg/kg body weight) and 2-PAM (100 mg/kg body weight) intraperitoneally]. MDA levels were observed to be higher and thiol content was lower in mitochondria from brain regions of OP exposed animals. This was accompanied by decreased activities of the mitochondrial enzymes; NADH dehydrogenase, succinate dehydrogenase, and cytochrome oxidase. In addition, mitochondrial functions assessed by MTT reduction also confirmed mitochondrial dysfunctions following development of OPIDN. The spatial long-term memory evaluated using elevated plus-maze test was observed to be deficit in OPIDN. The results suggest impaired mitochondrial functions as a mechanism involved in the development of organophosphate induced delayed neuropathy.
Collapse
Affiliation(s)
- Anwar Masoud
- Department of Biochemistry, Basic Medical Science Building, Panjab University, Chandigarh, 160014, India
| | | | | |
Collapse
|
32
|
Patki G, Che Y, Lau YS. Mitochondrial dysfunction in the striatum of aged chronic mouse model of Parkinson's disease. Front Aging Neurosci 2009; 1:3. [PMID: 20552054 PMCID: PMC2874410 DOI: 10.3389/neuro.24.003.2009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2009] [Accepted: 11/16/2009] [Indexed: 12/21/2022] Open
Abstract
Mitochondrial oxidative stress and dysfunction has been implicated as a possible mechanism for the onset and progression of Parkinson-like neurodegeneration. However, long-term mitochondrial defects in chronic animal neurodegenerative models have not been demonstrated. In this study, we investigated the function of striatal mitochondria 6 weeks after the induction of a chronic 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of Parkinson's disease (MPD). Although severe depression of mitochondrial respiration was observed immediately after acute administrations of MPTP, we failed to detect a significant mitochondrial inhibition in presence of striatal dopamine (DA) deficit 6 weeks after the chronic MPD induction in young adult mice. In contrast, when aged mice were chronically treated with MPTP and at 6 weeks post-treatment, these animals suffered an inhibition of the basal (state 4) and adenosine 5′-diphosphate-stimulated (state 3) respiration and a fall in adenosine triphosphate level in the striatal mitochondria. The aged chronic MPD also brought about a sustained diminution of striatal anti-oxidant enzyme levels including that of superoxide dismutases and cytochrome c. The mitochondrial deficits in the striatum of aged chronic MPD 6 weeks after treatment were further correlated with significant losses of striatal DA, tyrosine hydroxylase, DA uptake transporter, and with impaired movement when tested on a challenging beam. Our findings suggest that MPTP may trigger the neurodegenerative process by obstructing the mitochondrial function; however, striatal mitochondria in young animals may potentially rejuvenate, whereas mitochondrial dysfunction is sustained in the aged chronic MPD. Therefore, the aged chronic MPD may serve as a suitable investigative model for further elucidating the integral relationship between mitochondrial dysfunction and neurodegenerative disorder, and for assessing the therapeutic efficacy of mitochondrial protective agents as potential neuroprotective drugs.
Collapse
Affiliation(s)
- Gaurav Patki
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston Houston, TX, USA
| | | | | |
Collapse
|
33
|
Wang J, Rahman MF, Duhart HM, Newport GD, Patterson TA, Murdock RC, Hussain SM, Schlager JJ, Ali SF. Expression changes of dopaminergic system-related genes in PC12 cells induced by manganese, silver, or copper nanoparticles. Neurotoxicology 2009; 30:926-33. [PMID: 19781568 DOI: 10.1016/j.neuro.2009.09.005] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2009] [Revised: 09/03/2009] [Accepted: 09/15/2009] [Indexed: 11/30/2022]
Abstract
Nanoparticles have received a great deal of attention for producing new engineering applications due to their novel physicochemical characteristics. However, the broad application of nanomaterials has also produced concern for nanoparticle toxicity due to increased exposure from large-scale industry production. This study was conducted to investigate the potential neurotoxicity of manganese (Mn), silver (Ag), and copper (Cu) nanoparticles using the dopaminergic neuronal cell line, PC12. Selective genes associated with the dopaminergic system were investigated for expression changes and their correlation with dopamine depletion. PC12 cells were treated with 10 microg/ml Mn-40 nm, Ag-15 nm, or Cu-90 nm nanoparticles for 24 h. Cu-90 nanoparticles induced dopamine depletion in PC12 cells, which is similar to the effect induced by Mn-40 shown in a previous study. The expression of 11 genes associated with the dopaminergic system was examined using real-time RT-PCR. The expression of Txnrd1 was up-regulated after the Cu-90 treatment and the expression of Gpx1 was down-regulated after Ag-15 or Cu-90 treatment. These alterations are consistent with the oxidative stress induced by metal nanoparticles. Mn-40 induced a down-regulation of the expression of Th; Cu-90 induced an up-regulation of the expression of Maoa. This indicates that besides the oxidation mechanism, enzymatic alterations may also play important roles in the induced dopamine depletion. Mn-40 also induced a down-regulation of the expression of Park2; while the expression of Snca was up-regulated after Mn-40 or Cu-90 treatment. These data suggest that Mn and Cu nanoparticles-induced dopaminergic neurotoxicity may share some common mechanisms associated with neurodegeneration.
Collapse
Affiliation(s)
- Jianyong Wang
- Neurochemistry Laboratory, Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food & Drug Administration, 3900 NCTR Rd., Jefferson, AR 72079-9502, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
34
|
Hu X, Zhang D, Pang H, Caudle WM, Li Y, Gao H, Liu Y, Qian L, Wilson B, Di Monte DA, Ali SF, Zhang J, Block ML, Hong JS. Macrophage antigen complex-1 mediates reactive microgliosis and progressive dopaminergic neurodegeneration in the MPTP model of Parkinson's disease. THE JOURNAL OF IMMUNOLOGY 2008; 181:7194-204. [PMID: 18981141 DOI: 10.4049/jimmunol.181.10.7194] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Neuronal death is known to trigger reactive microgliosis. However, little is known regarding the manner by which microglia are activated by injured neurons and how microgliosis participates in neurodegeneration. In this study we delineate the critical role of macrophage Ag complex-1 (MAC1), a member of the beta(2) integrin family, in mediating reactive microgliosis and promoting dopaminergic (DAergic) neurodegeneration in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) model of Parkinson's disease. MAC1 deficiency greatly attenuated the DAergic neurodegeneration induced by MPTP or 1-methyl-4-phenyl-pyridium iodide (MPP(+)) exposure both in vivo and in vitro, respectively. Reconstituted experiments created by adding microglia from MAC1(-/-) or MAC1(+/+) mice back to MAC1(+/+) neuron-enriched cultures showed that microglia with functional MAC1 expression was mandatory for microglia-enhanced neurotoxicity. Both in vivo and in vitro morphological and Western blot studies demonstrated that MPTP/MPP(+) produced less microglia activation in MAC1(-/-) mice than MAC1(+/+) mice. Further mechanistic studies revealed that a MPP(+)-mediated increase in superoxide production was reduced in MAC1(-/-) neuron-glia cultures compared with MAC1(+/+) cultures. The stunted production of superoxide in MAC1(-/-) microglia is likely linked to the lack of translocation of the cytosolic NADPH oxidase (PHOX) subunit (p47(phox)) to the membrane. In addition, the production of PGE(2) markedly decreased in neuron plus MAC1(-/-) microglia cocultures vs neuron plus MAC1(+/+) microglia cocultures. Taken together, these results demonstrate that MAC1 plays a critical role in MPTP/MPP(+)-induced reactive microgliosis and further support the hypothesis that reactive microgliosis is an essential step in the self-perpetuating cycle leading to progressive DAergic neurodegeneration observed in Parkinson's disease.
Collapse
Affiliation(s)
- Xiaoming Hu
- Neuropharmacology Section, Laboratory of Pharmacology and Chemistry, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
35
|
Tareke E, Lyn-Cook B, Robinson B, Ali SF. Acrylamide: a dietary carcinogen formed in vivo? JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2008; 56:6020-6023. [PMID: 18624427 DOI: 10.1021/jf703749h] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Acrylamide, a chemical formed during heating of human foods, reacts with N-terminal valine in hemoglobin (Hb) and forms stable reaction products (adducts). These adducts to N-terminal valine in Hb have been used to estimate daily intake of acrylamide. Daily intake of acrylamide estimated from Hb adduct levels was higher than daily intake estimated from dietary questionnaires, possibly indicating other sources of exposures. Therefore, in this study the possible endogenous formation of acrylamide was investigated by treating mice with FeSO 4, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-hydrochloric acid (MPTP), or methamphetamine (METH). Acrylamide Hb adducts were determined, and a significant increase ( p < 0.05) in acrylamide Hb adduct levels was observed 24 h following treatment with FeSO 4 and 72 h following treatment with MPTP or METH. The results of this study show that acrylamide Hb adduct levels are increased in mice treated with compounds known to induce free radicals, thus suggesting the endogenous production of acrylamide.
Collapse
Affiliation(s)
- Eden Tareke
- Division of Personalized Nutrition and Medicine, Toxicologic Pathology Association, Inc., Jefferson, Arkansas 72079, USA.
| | | | | | | |
Collapse
|
36
|
Neural progenitor cells are protected against MPTP by MAO-B inhibitors. Neurotoxicology 2008; 29:1141-6. [PMID: 18606181 DOI: 10.1016/j.neuro.2008.05.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2008] [Revised: 04/22/2008] [Accepted: 05/16/2008] [Indexed: 11/21/2022]
Abstract
Neurotoxic effects of MPTP on the nigrostriatal dopaminergic system are thought to be initiated by 1-methyl-4-phenylpyridinium (MPP+), a metabolite formed by the monoamine oxidase (MAO)-B-mediated oxidation of MPTP. We previously reported that the administration of MPTP induced apoptosis in migrating neuroblasts (neural progenitor cells, NPCs) in adult mice. To determine whether MAO-B is also involved in the neurotoxicity of MPTP to NPCs, this study looked at the effects of MAO B inhibitors, R(-)-deprenyl (deprenyl) and N-(2-aminoethyl)-4-chlorobenzamide (Ro 16-6491), both of which protect the dopaminergic system against MPTP. Few apoptotic cells were found in saline- or MAO-B inhibitor-treated animals but MPTP markedly induced apoptosis in the subventricular zone (SVZ) and rostral migratory stream (RMS) after 1 day. When mice were pretreated with deprenyl or Ro 16-6491, not only nigrostriatal dopamine levels but also NPCs were significantly protected against MPTP. In addition, MPTP-induced apoptosis was found in both juvenile (postnatal 21 days) and older (12 months old) mice, suggesting NPCs to be different from the dopamine system, which has been thought to exhibit age-dependent susceptibility to MPTP.
Collapse
|
37
|
Comparison of the time courses of selective gene expression and dopaminergic depletion induced by MPP+ in MN9D cells. Neurochem Int 2008; 52:1037-43. [DOI: 10.1016/j.neuint.2007.10.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2007] [Revised: 08/14/2007] [Accepted: 10/29/2007] [Indexed: 11/18/2022]
|
38
|
Oyagi A, Oida Y, Hara H, Izuta H, Shimazawa M, Matsunaga N, Adachi T, Hara H. Protective effects of SUN N8075, a novel agent with antioxidant properties, in in vitro and in vivo models of Parkinson's disease. Brain Res 2008; 1214:169-76. [PMID: 18457816 DOI: 10.1016/j.brainres.2008.02.073] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2008] [Revised: 02/20/2008] [Accepted: 02/24/2008] [Indexed: 10/22/2022]
Abstract
SUN N8075 is a novel antioxidant with neuroprotective properties. This study was designed to elucidate its neuroprotective effects against 6-hydroxy dopamine (6-OHDA)-induced cell death and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced neurotoxicity (known as in vitro and in vivo models of Parkinson's disease, respectively). In the in vitro study, on human neuroblastoma SH-SY5Y cells, SUN N8075 decreased the hydrogen peroxide (H2O2)-induced production of reactive oxygen species and protected against 6-OHDA-induced cell death. In the in vivo study, SUN N8075, when injected intraperitoneally (i.p.) twice with a 5-h interval, inhibited lipid peroxidation (viz. the production of thiobarbituric acid reactive substance) in the mouse forebrain at 1 h after the second injection. Mice were injected i.p. with MPTP (10 mg/kg) four times at 1-h intervals, and brains were analyzed 7 days later. SUN N8075 at 30 mg/kg (i.p., twice) exhibited a protective effect against the MPTP-induced decrease in tyrosine hydroxylase (TH)-positive fibers in the striatum. Moreover, SUN N8075 at 10 and 30 mg/kg (i.p., twice) had a similar protective effect against the MPTP-induced decrease in TH-positive cells in the substantia nigra. Further, SUN N8075 30 mg/kg (i.p. twice) markedly suppressed the MPTP-induced accumulation of 8-hydroxy-deoxyguanosine (8-OHdG) in the striatum. These findings indicate that SUN N8075 exerts protective effects, at least in part via an anti-oxidation mechanism, in these in vitro and in vivo models of Parkinson's disease.
Collapse
Affiliation(s)
- A Oyagi
- Department of Biofunctional Evaluation, Molecular Pharmacology, Gifu Pharmaceutical University, 5-6-1 Mitahora-higashi, Gifu 502-8585, Japan
| | | | | | | | | | | | | | | |
Collapse
|
39
|
Devi L, Raghavendran V, Prabhu BM, Avadhani NG, Anandatheerthavarada HK. Mitochondrial import and accumulation of alpha-synuclein impair complex I in human dopaminergic neuronal cultures and Parkinson disease brain. J Biol Chem 2008; 283:9089-100. [PMID: 18245082 DOI: 10.1074/jbc.m710012200] [Citation(s) in RCA: 772] [Impact Index Per Article: 48.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Alpha-synuclein, a protein implicated in the pathogenesis of Parkinson disease (PD), is thought to affect mitochondrial functions, although the mechanisms of its action remain unclear. In this study we show that the N-terminal 32 amino acids of human alpha-synuclein contain cryptic mitochondrial targeting signal, which is important for mitochondrial targeting of alpha-synuclein. Mitochondrial imported alpha-synuclein is predominantly associated with the inner membrane. Accumulation of wild-type alpha-synuclein in the mitochondria of human dopaminergic neurons caused reduced mitochondrial complex I activity and increased production of reactive oxygen species. However, these defects occurred at an early time point in dopaminergic neurons expressing familial alpha-synuclein with A53T mutation as compared with wild-type alpha-synuclein. Importantly, alpha-synuclein that lacks mitochondrial targeting signal failed to target to the mitochondria and showed no detectable effect on complex I function. The PD relevance of these results was investigated using mitochondria of substantia nigra, striatum, and cerebellum of postmortem late-onset PD and normal human brains. Results showed the constitutive presence of approximately 14-kDa alpha-synuclein in the mitochondria of all three brain regions of normal subjects. Mitochondria of PD-vulnerable substantia nigra and striatum but not cerebellum from PD subjects showed significant accumulation of alpha-synuclein and decreased complex I activity. Analysis of mitochondria from PD brain and alpha-synuclein expressing dopaminergic neuronal cultures using blue native gel electrophoresis and immunocapture technique showed the association of alpha-synuclein with complex I. These results provide evidence that mitochondrial accumulated alpha-synuclein may interact with complex I and interfere with its functions.
Collapse
Affiliation(s)
- Latha Devi
- Department of Animal Biology, School of Veterinary Medicine, University of Pennsylvania, 3800 Spruce Street, Philadelphia, PA 19104, USA
| | | | | | | | | |
Collapse
|
40
|
McDermott JL, Dluzen DE. Aging and sex differences in striatal dopaminergic function. Neuroscience 2007; 149:401-8. [PMID: 17900817 DOI: 10.1016/j.neuroscience.2007.06.058] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2007] [Revised: 06/15/2007] [Accepted: 06/21/2007] [Indexed: 10/22/2022]
Abstract
In this report the potassium- (30 mM) and amphetamine- (10 microM) stimulated responses of dopamine (DA) and 3,4-dihydroxy phenylacetic acid (DOPAC) from superfused striatal tissue of female and male mice as sampled at 2, 6, 18 and 24 months of age were compared. When assessed relative to responses obtained from 2-month-old female mice, potassium-stimulated DA output of female mice was significantly decreased at 18 months of age and significantly increased at 24 months of age. In male mice, the only statistically significant change was an increase in potassium-stimulated DA in the 24 versus 2-month-old mice. In response to amphetamine-stimulation, DA responses from striatal tissue of 18-month-old females were significantly decreased and that of 24-month-old mice significantly increased relative to that of the 2-month-old females. In the case of male mice, amphetamine-stimulated DA responses of 6- and 18-month-old mice were significantly decreased compared with responses observed in the 2-month-old males. In addition, amphetamine-stimulated DA responses of the 24-month-old females were significantly greater than the 24-month-old males. In general, the response profiles for DOPAC to potassium and amphetamine stimulation were similar to that of DA for male, but not female, mice. These results demonstrate that sex differences in striatal dopaminergic function are differentially affected by age. Overall, striatal DA responsiveness of female mice shows more extreme age-related changes, particularly between the 2- and 6-month versus the 18- and 24-month-old mice and a discord between DA and DOPAC responses. Such extreme changes may be related to the presence (at 2 and 6 months) versus absence (at 18 and 24 months) of estrous cycles/gonadal steroid hormonal functions in female mice.
Collapse
Affiliation(s)
- J L McDermott
- Department of Anatomy, Northeastern Ohio Universities College of Medicine, 4209 State Route 44, P.O. Box 95, Rootstown, OH 44272-0095, USA
| | | |
Collapse
|
41
|
Wang J, Xu Z, Fang H, Duhart HM, Patterson TA, Ali SF. Gene expression profiling of MPP+-treated MN9D cells: A mechanism of toxicity study. Neurotoxicology 2007; 28:979-87. [PMID: 17475336 DOI: 10.1016/j.neuro.2007.02.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2007] [Revised: 02/22/2007] [Accepted: 02/27/2007] [Indexed: 01/06/2023]
Abstract
Parkinson's disease (PD) is a common neurodegenerative disease characterized by progressive loss of midbrain dopaminergic neurons with unknown etiology. MPP+ (1-methyl-4-phenylpyridinium) is the active metabolite of the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), which induces Parkinson's-like syndromes in humans and animals. MPTP/MPP+ treatment produces selective dopaminergic neuronal degeneration, therefore, these agents are commonly used to study the pathogenesis of PD. However, the mechanisms of their toxicity have not been elucidated. In order to gain insights into MPP+-induced neurotoxicity, a gene expression microarray study was performed using a midbrain-derived dopaminergic neuronal cell line, MN9D. Utilizing a two-color reference design, Agilent mouse oligonucleotide microarrays were used to examine relative gene expression changes in MN9D cells treated with 40microM MPP+ compared with controls. Bioinformatics tools were used for data evaluation. Briefly, raw data were imported into the NCTR ArrayTrack database, normalized using a Lowess method and data quality was assessed. The Student's t-test was used to determine significant changes in gene expression (set as p<0.05, fold change >1.5). Gene Ontology for Function Analysis (GOFFA) and Ingenuity Pathway Analysis were employed to analyze the functions and roles of significant genes in biological processes. Of the 51 significant genes identified, 44 were present in the GOFFA or Ingenuity database. These data indicate that multiple pathways are involved in the underlying mechanisms of MPP+-induced neurotoxicity, including apoptosis, oxidative stress, iron binding, cellular metabolism, and signal transduction. These data also indicate that MPP+-induced toxicity shares common molecular mechanisms with the pathogenesis of PD and further pathway analyses will be conducted to explore these mechanisms.
Collapse
Affiliation(s)
- Jianyong Wang
- Neurochemistry Laboratory, Division of Neurotoxicology, HFT-132, National Center for Toxicological Research/FDA, 3900 NCTR Road, Jefferson, AR 72079, USA
| | | | | | | | | | | |
Collapse
|
42
|
Rodrigues LG, Melo P, Silva MC, Tavares MA. Effects of postnatal exposure to methamphetamine on the development of the rat retina. Ann N Y Acad Sci 2007; 1074:604-19. [PMID: 17105956 DOI: 10.1196/annals.1369.059] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Since the development of different cell types in the retina occurs at different rates, it is possible that exposure to an exogenous substance may produce effects during one time period, but not during another. This study aims to analyze the effects of methamphetamine (METH) in the growth pattern of an experimental model as well as neurochemical and immunohistochemical parameters of the dopaminergic system of the rat retina. The three development stages chosen in this study are key markers in rat eye development. Rats were given 15 mg/kg body weight per day of METH as subcutaneous injections in 0.9% saline (3 mL/kg weight/day) from the day after birth PND 1 to PND 6, PND 13, and PND 29. Each daily dose was split into two. The control group was injected subcutaneously with saline. Both the schedule and volume for injecting saline in the control group were the same as for the METH-treated group. There were no significant differences in the total number of offspring per litter among treatment groups. All offspring had similar body weight at birth. Analysis of body weight on PND 1, showed that animals treated with METH had similar body weights to control-treated animals and females had smaller weights than males. For growth evolution, only litters with a sex ratio of four males and four females were used. Animals treated with METH had smaller body weights than the control-treated animals for all ages studied (PND 7, 14, and 30). Within the control group at PND 30, a significant difference was found in the body weight of females, which was lower when compared with males. For the postnatal model, 7 deaths occurred for the METH-exposed group. No deaths occurred in the control group in a total of 16 saline-injected litters comprising 186 pups. Although the levels of dopamine (DA) was within normal values for the postnatally exposed METH group when compared with its respective control group at PND 7 and 30, at PND 14 this was not the case: in this experimental group, the level of DA was lower than in the control group for both females and males. Support for this result was not evident from the TH immunoreactivity studies, probably because the methodology lacks the sensitivity to distinguish any mild effects, such as that observed in the postnatal model at PND 14. The level of the DA metabolite 3, 4-dihydroxyphenylacetic acid (DOPAC) remained unaffected at all ages studied, for both females and males. The results obtained in this study support the view that, during the critical periods in which the catecholamines can influence the development of neurones, METH transiently affects the pattern of the dopaminergic system in the developing retina.
Collapse
Affiliation(s)
- Lorena G Rodrigues
- UniLiPe, Institute for Molecular and Cell Biology, Rua do Campo Alegre, 823, 4150-180 Porto, Portugal.
| | | | | | | |
Collapse
|
43
|
Wang C, Sadovova N, Ali HK, Duhart HM, Fu X, Zou X, Patterson TA, Binienda ZK, Virmani A, Paule MG, Slikker W, Ali SF. L-carnitine protects neurons from 1-methyl-4-phenylpyridinium-induced neuronal apoptosis in rat forebrain culture. Neuroscience 2006; 144:46-55. [PMID: 17084538 DOI: 10.1016/j.neuroscience.2006.08.083] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2006] [Revised: 08/22/2006] [Accepted: 08/29/2006] [Indexed: 11/23/2022]
Abstract
1-Methyl-4-phenylpyridinium ion (MPP+), an inhibitor of mitochondrial complex I, has been widely used as a neurotoxin because it elicits a severe Parkinson's disease-like syndrome with an elevation of intracellular reactive oxygen species (ROS) and apoptosis. L-carnitine plays an integral role in attenuating the brain injury associated with mitochondrial neurodegenerative disorders. The present study investigates the effects of L-carnitine against the toxicity of MPP+ in rat forebrain primary cultures. Cells in culture were treated for 24 h with 100, 250, 500 and 1000 microM MPP+ alone or co-incubated with L-carnitine. MPP+ produced a dose-related increase in DNA fragmentation as measured by cell death ELISA (enzyme-linked immunosorbent assay), an increase in the number of TUNEL (terminal dUTP nick-end labeling)-positive cells and a reduction in the mitochondrial metabolism of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). No significant effect was observed with the release of lactate dehydrogenase (LDH), indicating that cell death presumably occurred via apoptotic mechanisms. Co-incubation of MPP+ with L-carnitine significantly reduced MPP+-induced apoptosis. Western blot analyses showed that neurotoxic concentrations of MPP+ decreased the ratio of BCL-X(L) to Bax and decreased the protein levels of polysialic acid neural cell adhesion molecules (PSA-NCAM), a neuron specific marker. L-carnitine blocked these effects of MPP+ suggesting its potential therapeutic utility in degenerative disorders such as Parkinson's disease, Alzheimer's disease, ornithine transcarbamylase deficiency and other mitochondrial diseases.
Collapse
Affiliation(s)
- C Wang
- Division of Neurotoxicology, HFT-132, National Center for Toxicological Research/U.S. Food and Drug Administration, Jefferson, AR 72079, USA.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
44
|
Melo P, Rodrigues LG, Silva MC, Tavares MA. Effects of Prenatal Exposure to Methamphetamine on the Development of the Rat Retina. Ann N Y Acad Sci 2006; 1074:590-603. [PMID: 17105955 DOI: 10.1196/annals.1369.058] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
In recent years there has been growing use of methamphetamine (METH) by pregnant women, resulting in an increasing number of children exposed prenatally to this drug of abuse. METH is known to be potentially neurotoxic to human adults, but there is minimal information with respect to the consequences of such exposure to the fetus. The purpose of this study was to ascertain external parameters of animal development, as well as neurochemical and immunohistochemical alterations at three key points of retinal development (postnatal day [PND] 7, 14, and 30). Rats of the Wistar strain were used in this experimental model. Pregnant females received a dose of 5 mg/kg body weight per day of METH-HCl in 0.9% saline, from gestational day (GD) 8 to 22. The control group to be used was pair fed and saline injected. Litters were randomly culled at PND 1 to 8 pups. Analysis of maternal body weight gain during pregnancy showed that females treated with METH had lower body weights than control-treated females. The body weight on PND 1, showed that animals treated with METH prenatally had smaller body weights than the control-treated animals and also that females weighed less than males. Prenatal exposure to METH did not alter the retinal levels of 3,4-dihydroxyphenylacetic acid (DOPAC) in the male group and the level of dopamine (DA) in both female and male groups when compared with their respective pair fed control groups during the first month of life. Correlating with the neurochemical data, no obvious changes on the localization of TH immunoreactivity in the rat retina at PND 7, 14, and 30 could be detected between control and METH-treated animals. Thus, exposure to METH disrupted this pattern in a gender-dependent manner. These data confirm previous observation that developing rats are protected against the adult type of METH-induced neurotoxicity. Therefore, conventional markers used for adult animals appear to be unsatisfactory to demarcate boundaries of the PND 1 to 30 critical periods.
Collapse
Affiliation(s)
- Pedro Melo
- Unit of Neurobehaviour, Institute for Molecular and Cell Biology, Rua do Campo Alegre, 823, 4150-180 Porto, Portugal.
| | | | | | | |
Collapse
|
45
|
Kaur D, Peng J, Chinta SJ, Rajagopalan S, Di Monte DA, Cherny RA, Andersen JK. Increased murine neonatal iron intake results in Parkinson-like neurodegeneration with age. Neurobiol Aging 2006; 28:907-13. [PMID: 16765489 DOI: 10.1016/j.neurobiolaging.2006.04.003] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2006] [Revised: 03/30/2006] [Accepted: 04/04/2006] [Indexed: 11/21/2022]
Abstract
Iron elevation is well-documented in the Parkinsonian midbrain but its cause and contribution to subsequent neurodegeneration remain unknown. Mice administered iron at doses equivalent to those found in iron-fortified human infant formula during a developmental period equivalent to the first human year of life display progressive midbrain neurodegeneration and enhanced vulnerability to toxic injury. This may have major implications for the impact of neonatal iron intake as a potential risk factor for later development of Parkinson's disease (PD).
Collapse
|
46
|
Luellen BA, Szapacs ME, Materese CK, Andrews AM. The neurotoxin 2′-NH2-MPTP degenerates serotonin axons and evokes increases in hippocampal BDNF. Neuropharmacology 2006; 50:297-308. [PMID: 16288930 DOI: 10.1016/j.neuropharm.2005.09.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2005] [Revised: 09/03/2005] [Accepted: 09/05/2005] [Indexed: 11/15/2022]
Abstract
1-Methyl-4-(2'-aminophenyl)-1,2,3,6-tetrahydropyridine (2'-NH2-MPTP) causes long-term depletions in cortical and hippocampal serotonin (5-HT) and norepinephrine (NE) that are accompanied by acute elevations in glial fibrillary acidic protein (GFAP) and argyrophilia. To further investigate the hypothesis that these changes are reflective of serotonergic and noradrenergic axonal degeneration, 2'-NH2-MPTP was administered to mice and innervation densities were determined immunocytochemically. Regional responses of the neurotrophin, brain-derived neurotrophic factor (BDNF), to putative damage were also assessed. Three days after 2'-NH2-MPTP, 5-HT axons exhibited a beaded, tortuous appearance indicative of ongoing degeneration. At 21 days, numbers of serotonin axons were significantly decreased, with the greatest axonal losses occurring in cortex and hippocampus. Serotonin axons in the amygdala were contrastingly spared long-term damage, as were 5-HT and NE cell bodies in the brain stem. BDNF protein levels were selectively increased in the hippocampus 3 days post-dose and returned to normal 21 days later. These results, in conjunction with previous findings, demonstrate that 2'-NH2-MPTP causes degeneration of serotonergic axons innervating the cortex and hippocampus on par with depletions in neurotransmitter levels. Moreover, damage to the hippocampus, a brain region important for learning and memory, and the modulation of anxiety and stress responsiveness, results in a transitory increase in BDNF.
Collapse
Affiliation(s)
- Beth A Luellen
- Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA 16802, USA
| | | | | | | |
Collapse
|
47
|
Xu Z, Cawthon D, McCastlain KA, Duhart HM, Newport GD, Fang H, Patterson TA, Slikker W, Ali SF. Selective alterations of transcription factors in MPP+-induced neurotoxicity in PC12 cells. Neurotoxicology 2005; 26:729-37. [PMID: 16112330 DOI: 10.1016/j.neuro.2004.12.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2004] [Revised: 01/10/2005] [Accepted: 12/13/2004] [Indexed: 01/02/2023]
Abstract
MPP(+) (1-methyl-4-phenylpyridinium; the active metabolite of the neurotoxin MPTP (1-methyl-4-phenyl-1,2,5,6-tetrahydropyridine)) depletes dopamine (DA) content and elicits cell death in PC12 cells. However, the mechanism of MPP(+)-induced neurotoxicity is still unclear. In this study, the dose response and time-course of MPP(+)-induced DA depletion and decreased cell viability were determined in nerve growth factor (NGF)-differentiated PC12 cells. The alteration of transcription factors (TFs) induced by MPP(+) from a selected dose level and time point was then evaluated using protein/DNA-binding arrays. K-means clustering analysis identified four patterns of protein/DNA-binding changes. Three of the 28 TFs identified in PC12 cells increased by 100% (p53, PRE, Smad SBE) and 2 decreased by 50% (HSE, RXR(DR1)) of control with MPP(+) treatment. In addition, three TFs decreased within the range of 33-50% (TFIID, E2F1, CREB) and two TFs increased within the range of 50-100% (PAX-5, Stat4). An electrophoretic mobility shift assay (EMSA) was used to confirm the changes of p53 and HSE. The observed changes in TFs correlated with the alterations of DA and cell viability. The data indicates that selective transcription factors are involved in MPP(+)-induced neurotoxicity and it provides mechanistic information that may be applicable to animal studies with MPTP and clinical studies of Parkinson's disease.
Collapse
Affiliation(s)
- Z Xu
- Neurochemistry Laboratory, Division of Neurotoxicology, HFT-132, National Center for Toxicological Research, Food and Drug Administration, 3900 NCTR Road, Jefferson, AR 72079, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
48
|
Ajjimaporn A, Swinscoe J, Shavali S, Govitrapong P, Ebadi M. Metallothionein provides zinc-mediated protective effects against methamphetamine toxicity in SK-N-SH cells. Brain Res Bull 2005; 67:466-75. [PMID: 16216695 DOI: 10.1016/j.brainresbull.2005.07.012] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2005] [Revised: 06/16/2005] [Accepted: 07/05/2005] [Indexed: 11/30/2022]
Abstract
Methamphetamine (METH) is a drug of abuse and neurotoxin that induces Parkinson's-like pathology after chronic usage by targeting dopaminergic neurons. Elucidation of the intracellular mechanisms that underlie METH-induced dopaminergic neuron toxicity may help in understanding the mechanism by which neurons die in Parkinson's disease. In the present study, we examined the role of reactive oxygen species (ROS) in the METH-induced death of human dopaminergic SK-N-SH cells and further assessed the neuroprotective effects of zinc and metallothionein (MT) against METH-induced toxicity in culture. METH significantly increased the production of reactive oxygen species, decreased intracellular ATP levels and reduced the cell viability. Pre-treatment with zinc markedly prevented the loss of cell viability caused by METH treatment. Zinc pre-treatment mainly increased the expression of metallothionein and prevented the generation of reactive oxygen species and ATP depletion caused by METH. Chelation of zinc by CaEDTA caused a significant decrease in MT expression and loss of protective effects of MT against METH toxicity. These results suggest that zinc-induced MT expression protects dopaminergic neurons via preventing the accumulation of toxic reactive oxygen species and halting the decrease in ATP levels. Furthermore, MT may prevent the loss of mitochondrial functions caused by neurotoxins. In conclusion, our study suggests that MT, a potent scavenger of free radicals is neuroprotective against dopaminergic toxicity in conditions such as drug of abuse and in Parkinson's disease.
Collapse
Affiliation(s)
- Amornpan Ajjimaporn
- Department of Pharmacology, University of North Dakota, School of Medicine and Health Sciences, Grand Forks, ND 58203, USA
| | | | | | | | | |
Collapse
|
49
|
Xu Z, Patterson TA, Wren JD, Han T, Shi L, Duhart H, Ali SF, Slikker W. A microarray study of MPP+-treated PC12 Cells: Mechanisms of toxicity (MOT) analysis using bioinformatics tools. BMC Bioinformatics 2005; 6 Suppl 2:S8. [PMID: 16026605 PMCID: PMC1637031 DOI: 10.1186/1471-2105-6-s2-s8] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Background This paper describes a microarray study including data quality control, data analysis and the analysis of the mechanism of toxicity (MOT) induced by 1-methyl-4-phenylpyridinium (MPP+) in a rat adrenal pheochromocytoma cell line (PC12 cells) using bioinformatics tools. MPP+ depletes dopamine content and elicits cell death in PC12 cells. However, the mechanism of MPP+-induced neurotoxicity is still unclear. Results In this study, Agilent rat oligo 22K microarrays were used to examine alterations in gene expression of PC12 cells after 500 μM MPP+ treatment. Relative gene expression of control and treated cells represented by spot intensities on the array chips was analyzed using bioinformatics tools. Raw data from each array were input into the NCTR ArrayTrack database, and normalized using a Lowess normalization method. Data quality was monitored in ArrayTrack. The means of the averaged log ratio of the paired samples were used to identify the fold changes of gene expression in PC12 cells after MPP+ treatment. Our data showed that 106 genes and ESTs (Expressed Sequence Tags) were changed 2-fold and above with MPP+ treatment; among these, 75 genes had gene symbols and 59 genes had known functions according to the Agilent gene Refguide and ArrayTrack-linked gene library. The mechanism of MPP+-induced toxicity in PC12 cells was analyzed based on their genes functions, biological process, pathways and previous published literatures. Conclusion Multiple pathways were suggested to be involved in the mechanism of MPP+-induced toxicity, including oxidative stress, DNA and protein damage, cell cycling arrest, and apoptosis.
Collapse
Affiliation(s)
- Zengjun Xu
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, 3900 NCTR Road, Jefferson, Arkansas 72079, USA
| | - Tucker A Patterson
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, 3900 NCTR Road, Jefferson, Arkansas 72079, USA
| | - Jonathan D Wren
- Advanced Center for Genome Technology, Department of Botany and Microbiology, 101 David L. Boren Blvd., The University of Oklahoma, Norman Oklahoma 73019, USA
| | - Tao Han
- Division of Systems Biology, National Center for Toxicological Research, U.S. Food and Drug Administration, 3900 NCTR Road, Jefferson, Arkansas 72079, USA
| | - Leming Shi
- Division of Systems Biology, National Center for Toxicological Research, U.S. Food and Drug Administration, 3900 NCTR Road, Jefferson, Arkansas 72079, USA
| | - Helen Duhart
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, 3900 NCTR Road, Jefferson, Arkansas 72079, USA
| | - Syed F Ali
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, 3900 NCTR Road, Jefferson, Arkansas 72079, USA
| | - William Slikker
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, 3900 NCTR Road, Jefferson, Arkansas 72079, USA
| |
Collapse
|
50
|
Genter MB. Update on olfactory mucosal metabolic enzymes: age-related changes and N-acetyltransferase activities. J Biochem Mol Toxicol 2005; 18:239-44. [PMID: 15452881 DOI: 10.1002/jbt.20029] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We have expanded previous observations on olfactory metabolic enzymes by examining the content of various metabolic enzymes in the olfactory mucosa of the male Long-Evans rat at different ages. Age-related changes in metabolic enzyme content may be related to changes in susceptibility to toxicants with age and may also contribute to altered odorant perception in the elderly. While some enzymes did not vary over the age range examined, decreases in the microsomal content of other enzymes were observed. While mRNA for acetyltransferase enzymes has previously been described in olfactory mucosa, the markedly higher activity of olfactory acetyltransferases compared to liver had not previously been described. Acetyltransferases are important in the metabolism of drugs and toxicants that are aromatic amine derivatives and may contribute to the bioactivation of rodent olfactory mucosal carcinogens such as 2,6-dimethylaniline and alachlor. These studies show that the olfactory mucosa varies in its metabolic capacity with age, and characterize another class of metabolic enzymes in the olfactory mucosa, both of which may impact significantly on responses to toxicants and therapeutic agents in the nasal cavity.
Collapse
Affiliation(s)
- Mary Beth Genter
- Department of Environmental Health, University of Cincinnati, Cincinnati, OH 45267-0056, USA.
| |
Collapse
|