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Wood SA, Hains PG, Muller A, Hill M, Premarathne S, Murtaza M, Robinson PJ, Mellick GD, Sykes AM. Proteomic profiling of idiopathic Parkinson's disease primary patient cells by SWATH-MS. Proteomics Clin Appl 2022; 16:e2200015. [PMID: 35579911 PMCID: PMC9787017 DOI: 10.1002/prca.202200015] [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: 02/01/2022] [Revised: 04/12/2022] [Accepted: 05/13/2022] [Indexed: 12/30/2022]
Abstract
PURPOSE Parkinson's disease (PD) is the second most prevalent neurodegenerative disease. It is generally diagnosed clinically after the irreversible loss of dopaminergic neurons and no general biomarkers currently exist. To gain insight into the underlying cellular causes of PD we aimed to quantify the proteomic differences between healthy control and PD patient cells. EXPERIMENTAL DESIGN Sequential Window Acquisition of all THeoretical Mass Spectra was performed on primary cells from healthy controls and PD patients. RESULTS In total, 1948 proteins were quantified and 228 proteins were significantly differentially expressed in PD patient cells. In PD patient cells, we identified seven significantly increased proteins involved in the unfolded protein response (UPR) and focused on cells with high and low amounts of PDIA6 and HYOU1. We discovered that PD patients with high amounts of PDIA6 and HYOU1 proteins were more sensitive to endoplasmic reticulum stress, in particular to tunicamycin. Data is available via ProteomeXchange with identifier PXD030723. CONCLUSIONS AND CLINICAL RELEVANCE This data from primary patient cells has uncovered a critical role of the UPR in patients with PD and may provide insight to the underlying cellular dysfunctions in these patients.
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Affiliation(s)
- Stephen A. Wood
- Griffith Institute for Drug DiscoveryGriffith UniversityNathanQueenslandAustralia
| | - Peter G. Hains
- Cell Signalling UnitChildren's Medical Research InstituteThe University of SydneyWestmeadNSWAustralia
| | | | - Melissa Hill
- Griffith Institute for Drug DiscoveryGriffith UniversityNathanQueenslandAustralia
| | - Susitha Premarathne
- Griffith Institute for Drug DiscoveryGriffith UniversityNathanQueenslandAustralia
| | - Mariyam Murtaza
- Griffith Institute for Drug DiscoveryGriffith UniversityNathanQueenslandAustralia
| | - Phillip J. Robinson
- Cell Signalling UnitChildren's Medical Research InstituteThe University of SydneyWestmeadNSWAustralia
| | - George D. Mellick
- Griffith Institute for Drug DiscoveryGriffith UniversityNathanQueenslandAustralia
| | - Alex M. Sykes
- Griffith Institute for Drug DiscoveryGriffith UniversityNathanQueenslandAustralia
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Harper SA, Dowdell BT, Kim JH, Pollock BS, Ridgel AL. Non-Motor Symptoms after One Week of High Cadence Cycling in Parkinson's Disease. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2019; 16:E2104. [PMID: 31197095 PMCID: PMC6616554 DOI: 10.3390/ijerph16122104] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 06/10/2019] [Accepted: 06/12/2019] [Indexed: 12/23/2022]
Abstract
The objective was to investigate if high cadence cycling altered non-motor cognition and depression symptoms in individuals with Parkinson's disease (PD) and whether exercise responses were influenced by brain-derived neurotrophic factor (BDNF) Val66Met polymorphism. Individuals with idiopathic PD who were ≥50 years old and free of surgical procedures for PD were recruited. Participants were assigned to either a cycling (n = 20) or control (n = 15) group. The cycling group completed three sessions of high cadence cycling on a custom motorized stationary ergometer. The primary outcome was cognition (attention, executive function, and emotion recognition were assessed via WebNeuro® and global cognition via Montreal Cognitive Assessment). Depression symptoms were assessed via Beck Depression Inventory-II. There was a main effect of time for emotional recognition (p = 0.048), but there were no other changes in cognition or depression symptoms. Regardless of intervention or Val66Met polymorphism, high cadence cycling does not alter cognition or depression symptoms after three sessions in one week.
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Affiliation(s)
- Sara A Harper
- Department of Medicine, Division of Gerontology, Geriatrics, and Palliative Care, University of Alabama at Birmingham, Birmingham, AL 35205, USA.
- Center for Exercise Medicine, University of Alabama at Birmingham, Birmingham, AL 35205, USA.
| | - Bryan T Dowdell
- Exercise Physiology Department, Kent State University, Kent, OH 44240, USA.
| | - Jin Hyun Kim
- Exercise Physiology Department, Kent State University, Kent, OH 44240, USA.
| | - Brandon S Pollock
- Department of Exercise Science, Walsh University, North Canton, OH 44720, USA.
| | - Angela L Ridgel
- Exercise Physiology Department, Kent State University, Kent, OH 44240, USA.
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Guo H, Shi F, Li M, Liu Q, Yu B, Hu L. Neuroprotective effects of Eucommia ulmoides Oliv. and its bioactive constituent work via ameliorating the ubiquitin-proteasome system. BMC COMPLEMENTARY AND ALTERNATIVE MEDICINE 2015; 15:151. [PMID: 25994206 PMCID: PMC4438574 DOI: 10.1186/s12906-015-0675-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 05/13/2015] [Indexed: 01/10/2023]
Abstract
BACKGROUND Parkinson's disease (PD) is a chronic neurodegenerative disorder characterized by a loss of dopaminergic neurons in the substantia nigra, decreased striatal dopamine levels, and consequent extrapyramidal motor dysfunction. The purpose of this study was to investigate potential in vivo protective effects of Duzhong against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), as well as the bioactive constituents against 1-methyl-4-phenylpyridinium (MPP(+)) toxicity in vitro. METHODS Male C57BL/6 mice were intraperitoneally administrated five consecutive injections of MPTP every 24 h at a dose of 30 mg/kg to induce an in vivo PD model. Pole and traction tests were performed in mice to evaluate motor deficits and bradykinesia after the final MPTP administration. The striatal levels of dopamine and its metabolites, 3,4-dihydroxyphenylacetic acid and homovanilic acid, were measured using a High-performance liquid chromatography-electrical conductivity detector. To further explore the bioactive constituents and protective mechanisms of Duzhong, seven compounds from Duzhong were tested on MPP(+)-treated SH-SY5Y cell lines in vitro. A proteasome enzymatic assay and Cell Counting Kit-8 were performed to examine proteasomal activity and cell viability of Duzhong-treated cells, respectively, after exposure to MPP(+) and proteasome inhibitor MG132. RESULTS Duzhong antagonized the loss of striatal neurotransmitters and relieved the associated anomaly in ambulatory locomotor activity in PD mice after a 3-day pre-treatment of Duzhong crude extract. The five Duzhong compounds attenuated MPP(+)-induced dysfunction of protease activity and reduced MG132-induced cytotoxicity. CONCLUSION Duzhong could serve as a potential candidate for PD treatment, and its mechanism involves the amelioration of the ubiquitin-proteasome system.
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Affiliation(s)
- Hong Guo
- Institute of Traditional Chinese Medicine, Tianjin University of Traditional Chinese Medicine, #312 Anshan Xi Road, Nankai District, Tianjin, 300193, China.
| | - Fang Shi
- Institute of Traditional Chinese Medicine, Tianjin University of Traditional Chinese Medicine, #312 Anshan Xi Road, Nankai District, Tianjin, 300193, China.
| | - Meijiao Li
- Institute of Traditional Chinese Medicine, Tianjin University of Traditional Chinese Medicine, #312 Anshan Xi Road, Nankai District, Tianjin, 300193, China.
| | - Qingqing Liu
- Institute of Traditional Chinese Medicine, Tianjin University of Traditional Chinese Medicine, #312 Anshan Xi Road, Nankai District, Tianjin, 300193, China.
| | - Bin Yu
- Institute of Traditional Chinese Medicine, Tianjin University of Traditional Chinese Medicine, #312 Anshan Xi Road, Nankai District, Tianjin, 300193, China.
| | - Limin Hu
- Institute of Traditional Chinese Medicine, Tianjin University of Traditional Chinese Medicine, #312 Anshan Xi Road, Nankai District, Tianjin, 300193, China.
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Sodium butyrate improves locomotor impairment and early mortality in a rotenone-induced Drosophila model of Parkinson's disease. Neuroscience 2013; 246:382-90. [PMID: 23623990 DOI: 10.1016/j.neuroscience.2013.04.037] [Citation(s) in RCA: 127] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Revised: 04/08/2013] [Accepted: 04/17/2013] [Indexed: 11/21/2022]
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder primarily affecting the dopaminergic neurons in the nigrastriatal pathway resulting in debilitating motor impairment in both familial and sporadic cases. Histone deacetylase (HDAC) inhibitors have been recently implicated as a therapeutic candidate because of their ability to correct the disrupted HDAC activity in PD and other neurodegenerative diseases. Sodium butyrate (SB), an HDAC inhibitor, reduces degeneration of dopaminergic neurons in a mutant alpha-synuclein Drosophila transgenic model of familial PD. Chronic exposure to the pesticide rotenone also causes selective degeneration of dopaminergic neurons and causes locomotor impairment and early mortality in a Drosophila model of chemically induced PD. This study investigated the effects of sodium butyrate on locomotor impairment and early mortality in a rotenone-induced PD model. We show that treatment with 10mM SB-supplemented food rescued the rotenone-induced locomotor impairment and early mortality in flies. Additionally, flies with the genetic knockdown of HDAC activity through Sin3A loss-of-function mutation (Sin3A(lof)) were resistant to rotenone-induced locomotor impairment and early mortality. Furthermore, SB-supplemented Sin3A(lof) flies had a modest additive effect for improving locomotor impairment. We also show SB-mediated improvement of rotenone-induced locomotor impairment was associated with elevated dopamine levels in the brain. However, the possibility of SB-mediated protective role through mechanisms independent from dopamine system is also discussed. These findings demonstrate that HDAC inhibitors like SB can ameliorate locomotor impairment in a rotenone-induced PD model.
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Blanc-Lapierre A, Bouvier G, Garrigou A, Canal-Raffin M, Raherison C, Brochard P, Baldi I. Effets chroniques des pesticides sur le système nerveux central : état des connaissances épidémiologiques. Rev Epidemiol Sante Publique 2012; 60:389-400. [DOI: 10.1016/j.respe.2012.03.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2011] [Revised: 02/23/2012] [Accepted: 03/26/2012] [Indexed: 12/14/2022] Open
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Overexpression of parkin ameliorates dopaminergic neurodegeneration induced by 1- methyl-4-phenyl-1,2,3,6-tetrahydropyridine in mice. PLoS One 2012; 7:e39953. [PMID: 22792139 PMCID: PMC3390003 DOI: 10.1371/journal.pone.0039953] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2012] [Accepted: 05/29/2012] [Indexed: 01/23/2023] Open
Abstract
Mutations in the parkin gene are currently thought to be the most common cause of recessive familial Parkinsonism. Parkin functions as an E3 ligase to regulate protein turnover, and its function in mitochondrial quality control has been reported recently. Overexpression of parkin has been found to prevent neuronal degeneration under various conditions both in vivo and in vitro. Here, we generated a transgenic mouse model in which expression of wild type parkin was driven by neuron-specific enolase (NSE) promoter. We reported that both young and old parkin transgenic mice exhibited less reduction of striatal TH protein and number of TH positive neurons in the substantia nigra induced by 1-Methyl-4-Phenyl-1,2,3,6-Tetrahydropyridine (MPTP), compared to wild type littermates. MPTP-induced mitochondrial impairment in the substantia nigra was improved in young parkin transgenic mice. Decreased striatal α-synuclein was demonstrated in old parkin transgenic mice. These results provide reliable evidence from the transgenic mouse model for parkin that overexpression of parkin may attenuate dopaminergic neurodegeneration induced by MPTP through protection of mitochondria and reduction of α-synuclein in the nigrostriatal pathway.
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Renoudet VV, Costa-Mallen P, Hopkins E. A diet low in animal fat and rich in N-hexacosanol and fisetin is effective in reducing symptoms of Parkinson's disease. J Med Food 2012; 15:758-61. [PMID: 22846082 DOI: 10.1089/jmf.2012.0060] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
This study describes how foods rich in fisetin and hexacosanol added to a strict diet reversed most symptoms of Parkinson's disease (PD) in one patient. This is a case report involving outpatient care. The subject was a dietitian diagnosed with idiopathic PD in 2000 at the age of 53 years old, with a history of exposure to neurotoxins and no family history of PD. A basic diet started in 2000 consisted of predominantly fruits, vegetables, 100% whole grains, extra virgin olive oil, nuts, seeds, nonfat milk products, tea, coffee, spices, small amounts of dark chocolate, and less than 25 g of animal fat daily. The basic diet alone failed to prevent decline due to PD. In 2009, the basic diet was enhanced with a good dietary source of both fisetin and hexacosanol. Six months after the patient started the enhanced diet rich in fisetin and hexacosanol, a clinically significant improvement in symptoms was noted; the patient's attending neurologist reported that the clinical presentation of cogwheel rigidity, micrographia, bradykinesia, dystonia, constricted arm swing with gait, hypomimia, and retropulsion appeared to be resolved. The only worsening of symptoms occurred when the diet was not followed precisely. Little improvement in tremor or seborrhea was observed. The clinical improvement has persisted to date. To the best of our knowledge, this is the first case where adjunctive diet therapy resulted in a significant reduction of symptoms of PD without changing the type or increasing the amount of medications.
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Pesticide exposure and Parkinson's disease: epidemiological evidence of association. Neurotoxicology 2012; 33:947-71. [PMID: 22627180 DOI: 10.1016/j.neuro.2012.05.011] [Citation(s) in RCA: 146] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Revised: 05/14/2012] [Accepted: 05/15/2012] [Indexed: 12/21/2022]
Abstract
It has been suggested that exposure to pesticides might be involved in the etiology of Parkinson's disease (PD). We conducted an updated systematic review of the epidemiologic literature over the past decade on the relationship between pesticide exposure and PD, using the MEDLINE database. Despite methodological differences, a significantly increased PD risk was observed in 13 out of 23 case-control studies that considered overall exposure to pesticides (risk estimates of 1.1-2.4) and in 10 out of 12 studies using other research designs (risk estimates of 2 or higher). Various studies found stronger associations in genetically susceptible individuals. Among a growing number of studies on the effects of exposure to specific pesticides (n=20), an increased PD risk has been associated with insecticides, especially chlorpyrifos and organochlorines, in six studies (odds ratios of 1.8-4.4), and with the herbicide paraquat, the fungicide maneb or the combination of both. Findings considerably strengthen the evidence that exposure to pesticides in well water may contribute to PD, whereas studies of farming and rural residence found inconsistent or little association with the disease. Taken together, this comprehensive set of results suggests that the hypothesis of an association between pesticide exposure and PD cannot be ruled out. However, inadequate data on consistent responses to exposure hinder the establishment of a causal relationship with PD. Given the extensive worldwide use of many pesticides, further studies are warranted in larger populations that include detailed quantitative data on exposure and determination of genetic polymorphisms.
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Le Couteur DG, McLachlan AJ, de Cabo R. Aging, drugs, and drug metabolism. J Gerontol A Biol Sci Med Sci 2011; 67:137-9. [PMID: 21768500 DOI: 10.1093/gerona/glr084] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Hilmer SN, Shenfield GM, Le Couteur DG. Clinical implications of changes in hepatic drug metabolism in older people. Ther Clin Risk Manag 2011; 1:151-6. [PMID: 18360554 PMCID: PMC1661619 DOI: 10.2147/tcrm.1.2.151.62914] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Prescribing for older people is challenging because of the paucity of clinical trial evidence of therapeutic benefit in this population and the presence of evidence that older people are at increased risk of adverse drug reactions. The outcomes of pharmacotherapies in older people depend on age-related changes in both pharmacokinetics and pharmacodynamics. Of the pharmacokinetic changes, those in hepatic metabolism are the most significant. Recent advances in biogerontology have improved our understanding of changes that occur in hepatic pharmacokinetics in older people. Knowledge of age-related changes in hepatic metabolism can guide prescribing and help reduce the risk–benefit ratio of using medications in older people.
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Song C, Kanthasamy A, Jin H, Anantharam V, Kanthasamy AG. Paraquat induces epigenetic changes by promoting histone acetylation in cell culture models of dopaminergic degeneration. Neurotoxicology 2011; 32:586-95. [PMID: 21777615 DOI: 10.1016/j.neuro.2011.05.018] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2011] [Revised: 04/22/2011] [Accepted: 05/23/2011] [Indexed: 11/15/2022]
Abstract
Environmental neurotoxic exposure to agrochemicals has been implicated in the etiopathogenesis of Parkinson's disease (PD). The widely used herbicide paraquat is among the few environmental chemicals potentially linked with PD. Since epigenetic changes are beginning to emerge as key mechanisms in neurodegenerative diseases, herein we examined the effects of paraquat on histone acetylation, a major epigenetic change in chromatin that can regulate gene expression, chromatin remodeling, cell survival and cell death. Exposure of N27 dopaminergic cells to paraquat induced histone H3 acetylation in a time-dependent manner. However, paraquat did not alter acetylation of another core histone H4. Paraquat-induced histone acetylation was associated with decreased total histone deacetylase (HDAC) activity and HDAC4 and 7 protein expression levels. To determine if histone acetylation plays a role in paraquat-induced apoptosis, the novel HAT inhibitor anacardic acid was used. Anacardic acid treatment significantly attenuated paraquat-induced caspase-3 enzyme activity, suppressed proteolytic activation and kinase activity of protein kinase C delta (PKCδ) and also blocked paraquat-induced cytotoxicity. Together, these results demonstrate that the neurotoxic agent paraquat induced acetylation of core histones in cell culture models of PD and that the inhibition of HAT activity by anacardic acid protects against apoptotic cell death, indicating that histone acetylation may represent key epigenetic changes in dopaminergic neuronal cells during neurotoxic insults.
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Affiliation(s)
- C Song
- Department of Biomedical Sciences, Iowa Center for Advanced Neurotoxicology, Iowa State University, Ames, IA 50011, USA
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NRF2 activation restores disease related metabolic deficiencies in olfactory neurosphere-derived cells from patients with sporadic Parkinson's disease. PLoS One 2011; 6:e21907. [PMID: 21747966 PMCID: PMC3128624 DOI: 10.1371/journal.pone.0021907] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2010] [Accepted: 06/14/2011] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Without appropriate cellular models the etiology of idiopathic Parkinson's disease remains unknown. We recently reported a novel patient-derived cellular model generated from biopsies of the olfactory mucosa (termed olfactory neurosphere-derived (hONS) cells) which express functional and genetic differences in a disease-specific manner. Transcriptomic analysis of Patient and Control hONS cells identified the NRF2 transcription factor signalling pathway as the most differentially expressed in Parkinson's disease. RESULTS We tested the robustness of our initial findings by including additional cell lines and confirmed that hONS cells from Patients had 20% reductions in reduced glutathione levels and MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt] metabolism compared to cultures from healthy Control donors. We also confirmed that Patient hONS cells are in a state of oxidative stress due to higher production of H(2)O(2) than Control cultures. siRNA-mediated ablation of NRF2 in Control donor cells decreased both total glutathione content and MTS metabolism to levels detected in cells from Parkinson's Disease patients. Conversely, and more importantly, we showed that activation of the NRF2 pathway in Parkinson's disease hONS cultures restored glutathione levels and MTS metabolism to Control levels. Paradoxically, transcriptomic analysis after NRF2 pathway activation revealed an increased number of differentially expressed mRNAs within the NRF2 pathway in L-SUL treated Patient-derived hONS cells compared to L-SUL treated Controls, even though their metabolism was restored to normal. We also identified differential expression of the PI3K/AKT signalling pathway, but only post-treatment. CONCLUSIONS Our results confirmed NRF2 as a potential therapeutic target for Parkinson's disease and provided the first demonstration that NRF2 function was inducible in Patient-derived cells from donors with uniquely varied genetic backgrounds. However, our results also demonstrated that the response of PD patient-derived cells was not co-ordinated in the same way as in Control cells. This may be an important factor when developing new therapeutics.
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Patki G, Lau YS. Melatonin protects against neurobehavioral and mitochondrial deficits in a chronic mouse model of Parkinson's disease. Pharmacol Biochem Behav 2011; 99:704-11. [PMID: 21741988 DOI: 10.1016/j.pbb.2011.06.026] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Revised: 06/21/2011] [Accepted: 06/24/2011] [Indexed: 12/21/2022]
Abstract
Neuronal oxidative stress and mitochondrial dysfunction have been implicated in Parkinson's disease. Melatonin is a natural antioxidant and free radical scavenger that has been shown to effectively reduce cellular oxidative stress and protect mitochondrial functions in vitro. However, whether melatonin is capable of slowing down the neurodegenerative process in animal models of Parkinson's disease remains controversial. In this research, we examined long-term melatonin treatment on striatal mitochondrial and dopaminergic functions and on animal locomotor performance in a chronic mouse model of Parkinson's disease originally established in our laboratory by gradually treating C57BL/6 mice with 10 doses of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (15 mg/kg, s.c.) and probenecid (250 mg/kg, i.p.) over five weeks. We report here that when the chronic Parkinsonian mice were pre-treated and continuously treated with melatonin (5mg/kg/day, i.p.) for 18 weeks, the defects of mitochondrial respiration, ATP and antioxidant enzyme levels detected in the striatum of chronic Parkinson's mice were fully preempted. Meanwhile, the striatal dopaminergic and locomotor deficits seen in the chronic Parkinson's mice were partially and significantly forestalled. These results imply that long-term melatonin is not only mitochondrial protective but also moderately neuronal protective in the chronic Parkinson's mice. Melatonin may potentially be effective for slowing down the progression of idiopathic Parkinson's disease and for reducing oxidative stress and respiratory chain inhibition in other mitochondrial disorders.
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Affiliation(s)
- Gaurav Patki
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, TX 77204, USA
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Martinez-Finley EJ, Avila DS, Chakraborty S, Aschner M. Insights from Caenorhabditis elegans on the role of metals in neurodegenerative diseases. Metallomics 2011; 3:271-9. [PMID: 21210060 PMCID: PMC3172965 DOI: 10.1039/c0mt00064g] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Neurodegeneration is characterized by the cell death or loss of structure and/or function of neurons. Many neurodegenerative diseases including Parkinson's disease (PD) and Alzheimer's disease (AD) are the result of neurodegenerative processes. Metals are essential for many life processes, but they are also culpable for several neurodegenerative mechanisms. In this review, we discuss the role of metals in neurodegenerative diseases with emphasis on the utility of Caenorhabditis elegans (C. elegans) genetic models in deciphering mechanisms associated with the etiology of PD and AD.
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Affiliation(s)
- Ebany J. Martinez-Finley
- Division of Clinical Pharmacology and Pediatric Toxicology, Vanderbilt University Medical Center, 11425 MRB IV, 2215-B Garland Ave., Nashville, TN 37232-0414, USA; Tel: 615-322-8024
- Center in Molecular Toxicology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Daiana Silva Avila
- Division of Clinical Pharmacology and Pediatric Toxicology, Vanderbilt University Medical Center, 11425 MRB IV, 2215-B Garland Ave., Nashville, TN 37232-0414, USA; Tel: 615-322-8024
| | - Sudipta Chakraborty
- Center in Molecular Toxicology, Vanderbilt University Medical Center, Nashville, TN, USA
- Center for Molecular Neuroscience, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Michael Aschner
- Division of Clinical Pharmacology and Pediatric Toxicology, Vanderbilt University Medical Center, 11425 MRB IV, 2215-B Garland Ave., Nashville, TN 37232-0414, USA; Tel: 615-322-8024
- Center in Molecular Toxicology, Vanderbilt University Medical Center, Nashville, TN, USA
- Center for Molecular Neuroscience, Vanderbilt University Medical Center, Nashville, TN, USA
- The Kennedy Center for Research on Human Development, Vanderbilt University Medical Center, Division of Pediatric Toxicology, Nashville, TN, USA
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Corder EH, Mellick GD. Parkinson's disease in relation to pesticide exposure and nuclear encoded mitochondrial complex I gene variants. J Biomed Biotechnol 2010; 2006:27601. [PMID: 17047302 PMCID: PMC1510938 DOI: 10.1155/jbb/2006/27601] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Parkinson's disease (PD) is a common age-related neurodegenerative disorder thought to result from the integrated effects of genetic
background and exposure to neuronal toxins. Certain individual nuclear-encoded mitochondrial complex I gene polymorphisms were found to be associated with ∼ 2-fold risk variation in an Australian case-control sample. We further characterized this
sample of 306 cases and 321 controls to determine the mutual information contained in the 22 SNPs and, additionally, level of pesticide exposure: five distinct risk sets were
identified using grade-of-membership analysis. Of these, one was robust to pesticide exposure (I), three were vulnerable (II, III, IV), and another (V) denoted low risk for unexposed persons. Risk for individual subjects varied > 16-fold according to level of membership in the vulnerable groups. We conclude that inherited variation in mitochondrial complex I genes and pesticide exposure together modulate risk for PD.
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Affiliation(s)
- Elizabeth H. Corder
- Center for Demographic Studies, Duke University, 2117
Campus Drive, PO Box 90408, Durham, NC 27708-0408, USA
- *Elizabeth H. Corder:
| | - George D. Mellick
- Eskitis Institute for Cell and Molecular Therapies, Griffith University, Nathan, QLD 4111 Australia
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Metabotropic glutamate receptor 1 mediates the electrophysiological and toxic actions of the cycad derivative beta-N-Methylamino-L-alanine on substantia nigra pars compacta DAergic neurons. J Neurosci 2010; 30:5176-88. [PMID: 20392940 DOI: 10.1523/jneurosci.5351-09.2010] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Amyotrophic lateral sclerosis-Parkinson dementia complex (ALS-PDC) is a neurodegenerative disease with ALS, parkinsonism, and Alzheimer's symptoms that is prevalent in the Guam population. beta-N-Methylamino alanine (BMAA) has been proposed as the toxic agent damaging several neuronal types in ALS-PDC, including substantia nigra pars compacta dopaminergic (SNpc DAergic) neurons. BMAA is a mixed glutamate receptor agonist, but the specific pathways activated in DAergic neurons are not yet known. We combined electrophysiology, microfluorometry, and confocal microscopy analysis to monitor membrane potential/current, cytosolic calcium concentration ([Ca(2+)](i)) changes, cytochrome-c (cyt-c) immunoreactivity, and reactive oxygen species (ROS) production induced by BMAA. Rapid toxin applications caused reversible membrane depolarization/inward current and increase of firing rate and [Ca(2+)](i) in DAergic neurons. The inward current (I(BMAA)) was mainly mediated by activation of metabotropic glutamate receptor 1 (mGluR1), coupled to transient receptor potential (TRP) channels, and to a lesser extent, AMPA receptors. Indeed, mGluR1 (CPCCOEt) and TRP channels (SKF 96365; Ruthenium Red) antagonists reduced I(BMAA), and a small component of I(BMAA) was reduced by the AMPA receptor antagonist CNQX. Calcium accumulation was mediated by mGluR1 but not by AMPA receptors. Application of a low concentration of NMDA potentiated the BMAA-mediated calcium increase. Prolonged exposure to BMAA caused significant modifications of membrane properties, calcium overload, cell shrinkage, massive cyt-c release into the cytosol and ROS production. In SNpc GABAergic neurons, BMAA activated only AMPA receptors. Our study identifies the mGluR1-activated mechanism induced by BMAA that may cause the neuronal degeneration and parkinsonian symptoms seen in ALS-PDC. Moreover, environmental exposure to BMAA might possibly also contribute to idiopathic PD.
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Song C, Kanthasamy A, Anantharam V, Sun F, Kanthasamy AG. Environmental neurotoxic pesticide increases histone acetylation to promote apoptosis in dopaminergic neuronal cells: relevance to epigenetic mechanisms of neurodegeneration. Mol Pharmacol 2010; 77:621-32. [PMID: 20097775 DOI: 10.1124/mol.109.062174] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Pesticide exposure has been implicated in the etiopathogenesis of Parkinson's disease (PD); in particular, the organochlorine insecticide dieldrin is believed to be associated with PD. Emerging evidence indicates that histone modifications play a critical role in cell death. In this study, we examined the effects of dieldrin treatment on histone acetylation and its role in dieldrin-induced apoptotic cell death in dopaminergic neuronal cells. In mesencephalic dopaminergic neuronal cells, dieldrin induced a time-dependent increase in the acetylation of core histones H3 and H4. Histone acetylation occurred within 10 min of dieldrin exposure indicating that acetylation is an early event in dieldrin neurotoxicity. The hyperacetylation was attributed to dieldrin-induced proteasomal dysfunction, resulting in accumulation of a key histone acetyltransferase (HAT), cAMP response element-binding protein. The novel HAT inhibitor anacardic acid significantly attenuated dieldrin-induced histone acetylation, Protein kinase C delta proteolytic activation and DNA fragmentation in dopaminergic cells protected against dopaminergic neuronal degeneration in primary mesencephalic neuronal cultures. Furthermore, 30-day exposure of dieldrin in mouse models induced histone hyperacetylation in the striatum and substantia nigra. For the first time, our results collectively demonstrate that exposure to the neurotoxic pesticide dieldrin induces acetylation of core histones because of proteasomal dysfunction and that hyperacetylation plays a key role in dopaminergic neuronal degeneration after exposure of dieldrin.
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Affiliation(s)
- C Song
- Iowa Center for Advanced Neurotoxicology, Department of Biomedical Sciences, Iowa State University, Ames, IA 50011, USA
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19
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Huang HY, Lin SZ, Chen WF, Li KW, Kuo JS, Wang MJ. Urocortin modulates dopaminergic neuronal survival via inhibition of glycogen synthase kinase-3β and histone deacetylase. Neurobiol Aging 2009; 32:1662-77. [PMID: 19875195 DOI: 10.1016/j.neurobiolaging.2009.09.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2009] [Revised: 08/19/2009] [Accepted: 09/27/2009] [Indexed: 11/27/2022]
Abstract
Urocortin (UCN) is a member of the corticotropin-releasing hormone (CRH) family of neuropeptides that regulates stress responses. Although UCN is principally expressed in dopaminergic neurons in rat substantia nigra (SN), the function of UCN in modulating dopaminergic neuronal survival remains unclear. Using primary mesencephalic cultures, we demonstrated that dopaminergic neurons underwent spontaneous cell death when their age increased in culture. Treatment of mesencephalic cultures with UCN markedly prolonged the survival of dopaminergic neurons, whereas neutralization of UCN with anti-UCN antibody accelerated dopaminergic neurons degeneration. UCN increased intracellular cAMP levels followed by phosphorylating glycogen synthase kinase-3β (GSK-3β) on Ser9. Moreover, UCN directly inhibited the histone deacetylase (HDAC) activity and induced a robust increase in histone H3 acetylation levels. Using pharmacological approaches, we further demonstrated that inhibition of GSK-3β and HDAC contributes to UCN-mediated neuroprotection. These results suggest that dopaminergic neuron-derived UCN might be involved in an autocrine protective signaling mechanism.
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Affiliation(s)
- Hsin-Yi Huang
- Department of Research, Neuro-Medical Scientific Center, Buddhist Tzu Chi General Hospital, Hualien 970, Taiwan, ROC
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20
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Sutherland GT, Siebert GA, Newman JRB, Silburn PA, Boyle RS, O'Sullivan JD, Mellick GD. Haplotype analysis of the PARK 11 gene, GIGYF2, in sporadic Parkinson's disease. Mov Disord 2009; 24:449-52. [PMID: 19117363 DOI: 10.1002/mds.22427] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Familial Parkinsonism (PARK) genes are strong candidates for conferring susceptibility to common forms of PD. However, most studies to date have provided little evidence that their common variants substantially influence disease risk. Recently, mutations were described in the gene, GIGYF2 (TNRC15), located at the PARK11 locus (2q37.1). Here, we use a haplotype tagging approach to examine common variation in the GIGYF2 gene and PD risk. PD cases (n = 568) and age and gender-matched control subjects (n = 568) were recruited from three specialist movement disorder clinics in Brisbane (Australia) and the Australian electoral roll. Twelve tagging SNPs were assessed in all subjects and haplotype and genotype associations were explored. Overall our findings suggest that common genetic variants of GIGYF2 do not significantly affect sporadic PD risk in Australian Caucasians.
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Affiliation(s)
- Greg T Sutherland
- Eskitis Institute for Cell and Molecular Therapies, School of Biomolecular and Physical Sciences, Griffith University, Brisbane, Queensland, Australia.
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21
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Sutherland G, Mellick G, Newman J, Double KL, Stevens J, Lee L, Rowe D, Silburn P, Halliday GM. Haplotype analysis of the IGF2-INS-TH gene cluster in Parkinson's disease. Am J Med Genet B Neuropsychiatr Genet 2008; 147B:495-9. [PMID: 18085551 DOI: 10.1002/ajmg.b.30633] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Idiopathic Parkinson's disease is a common movement disorder characterized by a loss of dopaminergic neurons in the substantia nigra. Its pathogenesis is postulated to involve complex interactions between genetic susceptibility and environmental exposures. The IGF2-INS-TH gene cluster on the telomeric end of human chromosome 11 is a gene rich region expressing several proteins important for dopamine neuron homeostasis. We used a haplotyping approach to determine whether common genetic variation in the IGF2-INS-TH cluster influences the risk of idiopathic Parkinson's disease in a Caucasian case-control group recruited from Brisbane, Australia. Three tagging polymorphisms, the SNPs, rs680 and rs689 and the microsatellite, HUMTH01, were genotyped in 215 cases and 215 age- and gender-matched controls. Eight common haplotypes accounted for 91% of the genetic variation in our control group and one haplotype, IGF2-INS-TH*6, was significantly under-represented among the cases with idiopathic Parkinson's disease (OR = 0.42, 95% CI = 0.25-0.72, P-value = 0.001). Analysis of the individual polymorphisms showed that the IGF2-rs680 alternate 'A' allele accounted for the majority of the protective effect. Our findings suggest that common genetic variants in the IGF2-INS-TH cluster modify susceptibility to idiopathic Parkinson's disease.
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Affiliation(s)
- Greg Sutherland
- School of Biomolecular and Biomedical Sciences, Eskitis Institute, Griffith University, Brisbane, Australia
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22
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Richter F, Hamann M, Richter A. Moderate degeneration of nigral neurons after repeated but not after single intrastriatal injections of low doses of 6-hydroxydopamine in mice. Brain Res 2008; 1188:148-56. [DOI: 10.1016/j.brainres.2007.09.083] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2007] [Revised: 09/26/2007] [Accepted: 09/27/2007] [Indexed: 11/27/2022]
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23
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Radad K, Gille G, Rausch WD. Dopaminergic neurons are preferentially sensitive to long-term rotenone toxicity in primary cell culture. Toxicol In Vitro 2007; 22:68-74. [PMID: 17923380 DOI: 10.1016/j.tiv.2007.08.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2006] [Revised: 07/06/2007] [Accepted: 08/08/2007] [Indexed: 12/21/2022]
Abstract
Parkinson's disease (PD) is a chronic neurodegenerative disorder characterized by the death of dopaminergic neurons in the substantia nigra pars compacta (SNpc) and the subsequent decrease of dopamine levels in the striatum. Epidemiological studies indicate environmental pollutants as a causative factor of sporadic PD. Experimental cell culture models have the inherent problem to mimic long-lasting neurodegeneration and to tackle its time-concentration relationship. The present study was designed to investigate the sensitivity of primary dopaminergic neurons to long-term rotenone exposure relevant to PD. Primary cultures prepared from embryonic mouse mesencephala were treated with nanomolar concentrations of rotenone (1, 3, 5, 10nM) on the 6th day in vitro (DIV) for 2, 4 and 6 days. The number of tyrosine hydroxylase immunoreactive (TH(+)) neurons and total hematoxylin-stained nuclei were counted. Astrocyte density was qualitatively evaluated by anti-glial fibrillary acidic protein (anti-GFAP) immunocytochemistry. It was found that dopaminergic neurons were highly sensitive to long-term rotenone treatment. Rotenone in a concentration- and time-dependent manner decreased the number of TH(+) neurons and led to degenerative changes of their morphology. Counting of the total cell number revealed a significant deleterious effect on the overall culture after 6 days of rotenone exposure. However, our study demonstrates a higher sensitivity of dopaminergic neurons to long-term exposure to nanomolar concentrations of rotenone. Other cells in the culture including non-dopaminergic neurons and glia cells appeared less affected compared to dopaminergic neurons.
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Affiliation(s)
- Khaled Radad
- Pathology Department, Faculty of Veterinary Medicine, Assiut University, Assiut 71526, Egypt.
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24
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Sutherland G, Mellick G, Sue C, Chan DKY, Rowe D, Silburn P, Halliday G. A functional polymorphism in the parkin gene promoter affects the age of onset of Parkinson's disease. Neurosci Lett 2007; 414:170-3. [PMID: 17280783 DOI: 10.1016/j.neulet.2006.12.051] [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] [Received: 10/13/2006] [Revised: 12/12/2006] [Accepted: 12/12/2006] [Indexed: 11/23/2022]
Abstract
Mutations in the parkin gene are the major cause of autosomal recessive early-onset forms of Parkinson's disease (PD). As reduced parkin expression might also affect the clinical course of idiopathic PD we investigated the effect of a low expressing allele in the parkin promoter region on the age at disease onset (AAO). Patients with PD (n=175) fulfilling standard diagnostic criteria were recruited by experienced neurologists at two movement disorders clinics in Sydney and Brisbane, Australia. DNA was extracted from whole blood and the -258 T/G polymorphism genotyped using PCR/RFLP. AAO effects were analysed using univariate ANOVA, binomial logistic regression modelling and Kaplan-Meier survival analysis. Subjects with the GG genotype (n=10, mean AAO=46.2+/-11.5 (S.D.) years) had a significantly lower mean AAO compared to the common TT genotype (n=104, mean AAO=56.1+/-12.7, p=0.02). There was no difference in mean AAO between the TT and TG individuals (n=61, mean AAO=55.3+/-11.6). Stratifying the sample by median AAO (55 years) revealed that the GG genotype was over-represented in the early-onset group (n=9, OR=18.6, 95% CI=1.41-245.3, p=0.03). We speculate that reduced expression of normal parkin protein may result in an early manifestation of PD symptoms.
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Affiliation(s)
- Greg Sutherland
- Prince of Wales Medical Research Institute, University of New South Wales, and Department of Neurology, Royal North Shore Hospital, Sydney, Australia
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25
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Chu Y, Kordower JH. Age-associated increases of alpha-synuclein in monkeys and humans are associated with nigrostriatal dopamine depletion: Is this the target for Parkinson's disease? Neurobiol Dis 2006; 25:134-49. [PMID: 17055279 DOI: 10.1016/j.nbd.2006.08.021] [Citation(s) in RCA: 312] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2006] [Revised: 08/31/2006] [Accepted: 08/31/2006] [Indexed: 01/12/2023] Open
Abstract
alpha-Synuclein is a synaptic protein that has been directly linked to both the etiology and pathogenesis of Parkinson's disease. We have previously shown that only nigral neurons in PD expressing alpha-synuclein inclusions display a loss dopaminergic phenotype. The present study tested the hypothesis that normal aging contributes to this effect. The relative abundance of alpha-synuclein protein within individual nigral neurons was quantified in eighteen normal humans between the age of 18 and 102 and twenty four rhesus monkeys between the age of 2 and 34. Optical densitometry revealed a robust age-related increase in alpha-synuclein protein within individual nigral neurons in both species. This effect was specific for nigral alpha-synuclein as no age-related changes were found in the ventral tegmental area nor were there changes in the nigra for non-pathogenic beta-synuclein. The age-related increases in nigral alpha-synuclein were non-aggregated and strongly associated with age-related decreases in tyrosine hydroxylase (TH), the rate limiting enzyme for dopamine production. In fact, only cells expressing alpha-synuclein displayed reductions in TH. We hypothesize that age-related increases in alpha-synuclein result in a subthreshold degeneration of nigrostriatal dopamine which, in PD, becomes symptomatic due to lysosomal failure resulting in protein misfolding and inclusion formation. We further hypothesize that preventing the age-related accumulation of non-aggregated alpha-synuclein might be a simple and potent therapeutic target for patients with PD.
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Affiliation(s)
- Yaping Chu
- Department of Neurological Sciences, Rush University Medical Center, 1735 West Harrison Street, Chicago, IL 60612, USA
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26
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Phinney AL, Andringa G, Bol JGJM, Wolters EC, van Muiswinkel FL, van Dam AMW, Drukarch B. Enhanced sensitivity of dopaminergic neurons to rotenone-induced toxicity with aging. Parkinsonism Relat Disord 2006; 12:228-38. [PMID: 16488175 DOI: 10.1016/j.parkreldis.2005.12.002] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2005] [Accepted: 12/14/2005] [Indexed: 12/21/2022]
Abstract
Rotenone has been reported to induce various degrees of Parkinsonism in rats. We tested whether advancing age alters the sensitivity of dopaminergic neurons to rotenone. A low, systemic dose of rotenone had no effect on young rats, but led to a 20-30% reduction of tyrosine hydroxylase-positive neurons in the substantia nigra of older rats. The effect was specific to nigral dopaminergic neurons and may be associated with the increase of glial cell activation in older rats. These data suggest that age enhances the sensitivity of dopaminergic neurons to rotenone and should be considered when assessing models of Parkinson's disease.
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Affiliation(s)
- Amie L Phinney
- Department of Medical Pharmacology, Institute for Clinical and Experimental Neurosciences, VU University Medical Center, Van der Boechorststraat 7, 1081 BT Amsterdam, The Netherlands
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27
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Motsinger AA, Lee SL, Mellick G, Ritchie MD. GPNN: power studies and applications of a neural network method for detecting gene-gene interactions in studies of human disease. BMC Bioinformatics 2006; 7:39. [PMID: 16436204 PMCID: PMC1388239 DOI: 10.1186/1471-2105-7-39] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2005] [Accepted: 01/25/2006] [Indexed: 01/17/2023] Open
Abstract
Background The identification and characterization of genes that influence the risk of common, complex multifactorial disease primarily through interactions with other genes and environmental factors remains a statistical and computational challenge in genetic epidemiology. We have previously introduced a genetic programming optimized neural network (GPNN) as a method for optimizing the architecture of a neural network to improve the identification of gene combinations associated with disease risk. The goal of this study was to evaluate the power of GPNN for identifying high-order gene-gene interactions. We were also interested in applying GPNN to a real data analysis in Parkinson's disease. Results We show that GPNN has high power to detect even relatively small genetic effects (2–3% heritability) in simulated data models involving two and three locus interactions. The limits of detection were reached under conditions with very small heritability (<1%) or when interactions involved more than three loci. We tested GPNN on a real dataset comprised of Parkinson's disease cases and controls and found a two locus interaction between the DLST gene and sex. Conclusion These results indicate that GPNN may be a useful pattern recognition approach for detecting gene-gene and gene-environment interactions.
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Affiliation(s)
- Alison A Motsinger
- Center for Human Genetics Research and Department of Molecular Physiology and Biophysics, Vanderbilt University Medical School, Nashville, TN, 37232-0700, USA
| | - Stephen L Lee
- Dartmouth Medical School, One Medical Center Drive, Lebanon, New Hampshire 03756-001, USA
| | - George Mellick
- University of Queensland, School of Medicine and Department of Neurology, Princess Alexandra Hospital, Brisbane, Australia
| | - Marylyn D Ritchie
- Center for Human Genetics Research and Department of Molecular Physiology and Biophysics, Vanderbilt University Medical School, Nashville, TN, 37232-0700, USA
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28
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Novikova L, Garris BL, Garris DR, Lau YS. Early signs of neuronal apoptosis in the substantia nigra pars compacta of the progressive neurodegenerative mouse 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine/probenecid model of Parkinson’s disease. Neuroscience 2006; 140:67-76. [PMID: 16533572 DOI: 10.1016/j.neuroscience.2006.02.007] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2005] [Revised: 01/27/2006] [Accepted: 02/01/2006] [Indexed: 11/26/2022]
Abstract
Parkinson's disease is associated with a progressive loss of substantia nigra pars compacta dopaminergic neurons. The cellular and molecular mechanisms underlying Parkinson's disease neurodegeneration have not been fully determined. Clinical investigations and subacute in vivo studies using the neurotoxin, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine have generated some observations suggesting that apoptosis is involved in neurodegeneration; however, this view remains equivocal. In this study, the substantia nigra pars compacta neurodegenerative process was examined in the chronic mouse 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine/probenecid model of Parkinson's disease treated with 10 doses of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (25 mg/kg) and probenecid (250 mg/kg) over five weeks. One day after chronic treatment, numerous terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling-positive cells were detected specifically in the substantia nigra pars compacta displaying shrunken volume, chromatin condensation, and DNA fragmentation. The number of apoptotic cells declined over time. No terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling-positive cells were found in untreated or probenecid-treated control animals. Cytomorphometric analysis of substantia nigra pars compacta nuclear loci revealed eccentric nucleoli dislocation and vesicular degranulation in all of the apoptotic neurons for the mouse 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine/probenecid model for Parkinson's disease. The terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling-positive cells phenotypically showed neuronal origin (NeuN-positive) with a loss of tyrosine hydroxylase immunoreactivity. While the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling-positive cells were not co-localized with astroglial (GFAP-positive) cells, some apoptotic cells were clearly associated with the activated microglial (macrophage antigen complex-1 and isolectin B(4)-positive) cells suggesting an active process of dead cell removal. In the one-day and seven-day post-treated mouse 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine/probenecid model for Parkinson's disease, marked depression of tyrosine hydroxylase immunoreactivity in the substantia nigra pars compacta and striatum was observed, which was correlated with significant reductions of striatal dopamine content and uptake. These results suggest that initial neuronal apoptosis and morphological changes are involved, at least in part, in the chronic neurodegeneration of mouse 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine/probenecid model for Parkinson's disease.
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Affiliation(s)
- L Novikova
- Division of Pharmacology, School of Pharmacy, University of Missouri-Kansas City, Kansas City, MO 64108, USA
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29
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Lau YS, Novikova L, Roels C. MPTP treatment in mice does not transmit and cause Parkinsonian neurotoxicity in non-treated cagemates through close contact. Neurosci Res 2005; 52:371-8. [PMID: 15936837 DOI: 10.1016/j.neures.2005.04.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2005] [Revised: 04/16/2005] [Accepted: 04/28/2005] [Indexed: 12/21/2022]
Abstract
1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) is currently a leading neurotoxic agent used for producing Parkinsonism in laboratory animals. The MPTP neurotoxicity in humans is irreversible and the consequential clinical and neurochemical features closely resemble those of the idiopathic Parkinson's disease. Therefore, handling of MPTP in laboratory may pose neurotoxic risk among researchers and animal caretakers. While it is well recognized that systemic administration of MPTP will cause Parkinsonian-like symptoms in humans and animals, it is not known whether similar neurological toxicity is transmittable and would develop in normal subjects housed closely with the MPTP-treated animals. In the present study, we treated mice daily with MPTP hydrochloride (30mg/kg, s.c.) for 5 consecutive days. In the same cage, a non-treated mouse (cagemate) was kept allowing for close physical interaction, free contact with the excreta, and sharing of food and water. Seventy-two hours after the treatment, the MPTP-treated mice and MPTP-exposed cagemates were analyzed for dopaminergic neurotoxicity comparing with the MPTP non-exposed control animals. We detected a significant number of TUNEL-positive cells, loss of tyrosine hydroxylase immunoreactivity in the substantia nigra, and depletion of dopamine in the striatum of MPTP-treated mice. However, these neurotoxic indices were not detected in the MPTP-exposed cagemates or MPTP non-exposed controls. Following each MPTP injection, approximately 42% of the chemical was excreted within 3h through the urine largely in the form of MPTP N-oxide, which is not expected to cross the blood-brain barrier and to cause dopaminergic toxicity in the brain when administered peripherally. These observations suggest that MPTP injections in mice do not transmit and cause Parkinsonian-like dopaminergic neurotoxicity in the neighboring normal cagemates through direct physical contact and exposure from the contaminated cage, food, water, and excreta.
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MESH Headings
- 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine/administration & dosage
- 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine/urine
- 3,4-Dihydroxyphenylacetic Acid/metabolism
- Animals
- Apoptosis/drug effects
- Apoptosis/physiology
- Blotting, Western/methods
- Chromatography, High Pressure Liquid/methods
- Disease Models, Animal
- Dopamine/metabolism
- Immunohistochemistry/methods
- In Situ Nick-End Labeling/methods
- Male
- Mice
- Mice, Inbred C57BL
- Parkinsonian Disorders/metabolism
- Parkinsonian Disorders/pathology
- Statistics, Nonparametric
- Substantia Nigra/drug effects
- Substantia Nigra/metabolism
- Substantia Nigra/pathology
- Tyrosine 3-Monooxygenase/metabolism
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Affiliation(s)
- Yuen-Sum Lau
- Division of Pharmacology, University of Missouri-Kansas City School of Pharmacy, 2411 Holmes Street, Kansas City, MO 64108, USA.
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30
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Spires TL, Hannan AJ. Nature, nurture and neurology: gene-environment interactions in neurodegenerative disease. FEBS Anniversary Prize Lecture delivered on 27 June 2004 at the 29th FEBS Congress in Warsaw. FEBS J 2005; 272:2347-61. [PMID: 15885086 DOI: 10.1111/j.1742-4658.2005.04677.x] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Neurodegenerative disorders, such as Huntington's, Alzheimer's, and Parkinson's diseases, affect millions of people worldwide and currently there are few effective treatments and no cures for these diseases. Transgenic mice expressing human transgenes for huntingtin, amyloid precursor protein, and other genes associated with familial forms of neurodegenerative disease in humans provide remarkable tools for studying neurodegeneration because they mimic many of the pathological and behavioural features of the human conditions. One of the recurring themes revealed by these various transgenic models is that different diseases may share similar molecular and cellular mechanisms of pathogenesis. Cellular mechanisms known to be disrupted at early stages in multiple neurodegenerative disorders include gene expression, protein interactions (manifesting as pathological protein aggregation and disrupted signaling), synaptic function and plasticity. Recent work in mouse models of Huntington's disease has shown that enriching the environment of transgenic animals delays the onset and slows the progression of Huntington's disease-associated motor and cognitive symptoms. Environmental enrichment is known to induce various molecular and cellular changes in specific brain regions of wild-type animals, including altered gene expression profiles, enhanced neurogenesis and synaptic plasticity. The promising effects of environmental stimulation, demonstrated recently in models of neurodegenerative disease, suggest that therapy based on the principles of environmental enrichment might benefit disease sufferers and provide insight into possible mechanisms of neurodegeneration and subsequent identification of novel therapeutic targets. Here, we review the studies of environmental enrichment relevant to some major neurodegenerative diseases and discuss their research and clinical implications.
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Affiliation(s)
- Tara L Spires
- MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA
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31
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Le Couteur DG, Fraser R, Hilmer S, Rivory LP, McLean AJ. The Hepatic Sinusoid in Aging and Cirrhosis. Clin Pharmacokinet 2005; 44:187-200. [PMID: 15656697 DOI: 10.2165/00003088-200544020-00004] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The fenestrated sinusoidal endothelium ('liver sieve') and space of Disse in the healthy liver do not impede the transfer of most substrates, including drugs and oxygen, from the sinusoidal lumen to the hepatocyte. Plasma components transfer freely in both directions through the endothelial fenestrations and into the space of Disse. The endothelium is attenuated, there is no basement membrane and there is minimum collagen in the space of Disse, thus minimising any barriers to substrate diffusion. Both cirrhosis and aging are associated with marked structural changes in the sinusoidal endothelium and space of Disse that are likely to influence bulk plasma transfer into the space of Disse, and diffusion through the endothelium and space of Disse. These changes, termed capillarisation and pseudocapillarisation in cirrhosis and aging, respectively, impede the transfer of various substrates. Capillarisation is associated with exclusion of albumin, protein-bound drugs and macromolecules from the space of Disse, and the progressive transformation of flow-limited to barrier-limited distribution of some substrates. There is evidence that the sinusoidal changes in cirrhosis and aging contribute to hepatocyte hypoxia, thus providing a mechanism for the apparent differential reduction of oxygen-dependent phase I metabolic pathways in these conditions. Structural change and subsequent dysfunction of the liver sieve warrant consideration as a significant factor in the impairment of overall substrate handling and hepatic drug metabolism in cirrhosis and aging.
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Affiliation(s)
- David G Le Couteur
- Centre for Education and Research on Ageing and ANZAC Research Institute, University of Sydney, Sydney, New South Wales, Australia.
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32
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Ling Z, Chang QA, Tong CW, Leurgans SE, Lipton JW, Carvey PM. Rotenone potentiates dopamine neuron loss in animals exposed to lipopolysaccharide prenatally. Exp Neurol 2004; 190:373-83. [PMID: 15530876 DOI: 10.1016/j.expneurol.2004.08.006] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2004] [Revised: 07/26/2004] [Accepted: 08/12/2004] [Indexed: 12/21/2022]
Abstract
We previously demonstrated that treating gravid female rats with the bacteriotoxin lipopolysaccharide (LPS) led to the birth of offspring with fewer than normal dopamine (DA) neurons. This DA neuron loss was long-lived and associated with permanent increases in the pro-inflammatory cytokine tumor necrosis factor alpha (TNFalpha). Because of this pro-inflammatory state, we hypothesized that these animals would be more susceptible to subsequent exposure of DA neurotoxins. We tested this hypothesis by treating female Sprague-Dawley rats exposed to LPS or saline prenatally with a subtoxic dose of the DA neurotoxin rotenone (1.25 mg/kg per day) or vehicle for 14 days when they were 16 months old. After another 14 days, the animals were sacrificed. Tyrosine hydroxylase-immunoreactive (THir) cell counts were used as an index of DA neuron survival. Animals exposed to LPS prenatally or rotenone postnatally exhibited a 22% and 3%, respectively, decrease in THir cell counts relative to controls. The combined effects of prenatal LPS and postnatal rotenone exposure produced a synergistic 39% THir cell loss relative to controls. This loss was associated with decreased striatal DA and increased striatal DA activity ([HVA]/[DA]) and TNFalpha. Animals exposed to LPS prenatally exhibited a marked increase in the number of reactive microglia that was further increased by rotenone exposure. Prenatal LPS exposure also led to increased levels of oxidized proteins and the formation of alpha-Synuclein and eosin positive inclusions resembling Lewy bodies. These results suggest that exposure to low doses of an environmental neurotoxin like rotenone can produce synergistic DA neuron losses in animals with a preexisting pro-inflammatory state. This supports the notion that Parkinson's disease (PD) may be caused by multiple factors and the result of "multiple hits" from environmental toxins.
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Affiliation(s)
- Zaodung Ling
- Department of Pharmacology, Rush University Medical Center, Chicago, IL 60612, USA.
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Hering R, Strauss KM, Tao X, Bauer A, Woitalla D, Mietz EM, Petrovic S, Bauer P, Schaible W, Müller T, Schöls L, Klein C, Berg D, Meyer PT, Schulz JB, Wollnik B, Tong L, Krüger R, Riess O. Novel homozygous p.E64D mutation in DJ1 in early onset Parkinson disease (PARK7). Hum Mutat 2004; 24:321-9. [PMID: 15365989 DOI: 10.1002/humu.20089] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Mutations in the parkin gene have been identified as a common cause of autosomal recessive inherited Parkinson disease (PD) associated with early disease manifestation. However, based on linkage data, mutations in other genes contribute to the genetic heterogeneity of early-onset PD (EOPD). Recently, two mutations in the DJ1 gene were described as a second cause of autosomal recessive EOPD (PARK7). Analyzing the PARK7/DJ1 gene in 104 EOPD patients, we identified a third mutation, c.192G>C (p.E64D), associated with EOPD in a patient of Turkish ancestry and characterized the functional significance of this amino acid substitution. In the patient, a substantial reduction of dopamine uptake transporter (DAT) binding was found in the striatum using [(18)F]FP-CIT and PET, indicating a serious loss of presynaptic dopaminergic afferents. His sister, homozygous for E64D, was clinically unaffected but showed reduced dopamine uptake when compared with a clinically unaffected brother, who is heterozygous for E64D. We demonstrate by crystallography that the E64D mutation does not alter the structure of the DJ1 protein, however we observe a tendency towards decreased levels of the mutant protein when overexpressed in HEK293 or COS7 cells. Using immunocytochemistry in contrast to the homogenous nuclear and cytoplasmic staining in HEK293 cells overexpressing wild-type DJ1, about 5% of the cells expressing E64D and up to 80% of the cells expressing the recently described L166P mutation displayed a predominant nuclear localization of the mutant DJ1 protein.
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Affiliation(s)
- Robert Hering
- Department of Medical Genetics, University of Tübingen, Tübingen, Germany
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Deng Y, Newman B, Dunne MP, Silburn PA, Mellick GD. Case-only study of interactions between genetic polymorphisms of GSTM1, P1, T1 and Z1 and smoking in Parkinson’s disease. Neurosci Lett 2004; 366:326-31. [PMID: 15288444 DOI: 10.1016/j.neulet.2004.05.061] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2004] [Revised: 05/20/2004] [Accepted: 05/22/2004] [Indexed: 11/30/2022]
Abstract
Current opinion contends that complex interactions between genetic and environmental factors play a role in the etiology of Parkinson's disease (PD). Cigarette smoking is thought to reduce risk of PD, and emerging evidence suggests that genetic factors may modulate smoking's effect. We used a case-only design, an approach not previously used to study gene-environment interactions in PD, specifically to study interactions between glutathione-S-transferase (GST) gene polymorphisms and smoking in relation to PD. Four-hundred PD cases (age at onset: 60.0 +/- 10.7 years) were genotyped for common polymorphisms in GSTM1, P1, T1 and Z1 using well-established methods. Smoking exposure data were collected in face-to-face interviews. The independence of the studied GST genotypes and smoking exposure was confirmed by studying 402 healthy, aged individuals. No differences were observed in the distributions of GSTM1, T1 or Z1 polymorphisms between ever-smoked and never-smoked PD cases using logistic regression (all P > 0.43). However, GSTP1 *C haplotypes were over-represented among PD cases who ever smoked (odds ratio for interaction (ORi) = 2.00 (95% CI: 1.11-3.60, P = 0.03)). Analysis revealed that ORi between smoking and the GSTP1-114Val carrier status increased with increasing smoking dose (P = 0.02 for trend). These data suggest that one or more GSTP1 polymorphisms may interact with cigarette smoking to influence the risk for PD.
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Affiliation(s)
- Yifu Deng
- Centre for Health Research, School of Public Health, Queensland University of Technology, Kelvin Grove, Qld. 4059, Australia
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Albers JW, Berent S, Garabrant DH, Giordani B, Schweitzer SJ, Garrison RP, Richardson RJ. The effects of occupational exposure to chlorpyrifos on the neurologic examination of central nervous system function: a prospective cohort study. J Occup Environ Med 2004; 46:367-78. [PMID: 15076655 DOI: 10.1097/01.jom.0000121127.29733.5c] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Questions persist about adverse effects such as impaired cognition and attention, incoordination, spasticity, or parkinsonism from chronic, low-level exposures to organophosphate (OP) compounds. In a prospective cohort study, we evaluated chlorpyrifos-manufacturing workers and a referent group on 2 occasions, 1 year apart, to determine whether occupational exposure to chlorpyrifos produced clinically evident central nervous system (CNS) dysfunction. Chlorpyrifos subjects had significantly higher TCP excretion and lower average BuChE activity than referents in a range in which physiological effects on B-esterases exist. Few subjects had neurologic symptoms or signs, and there were no significant group differences in terms of signs at baseline or second examinations. Chronic chlorpyrifos exposure produced no clinical evidence of cortical, pyramidal tract, extrapyramidal, or other CNS dysfunction among chlorpyrifos subjects compared with referents, either at baseline or after 1 year of additional chlorpyrifos exposure.
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Affiliation(s)
- James W Albers
- Department of Neurology, University of Michigan Health Systems, Ann Arbor 48109-0032, USA.
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Paolini M, Sapone A, Gonzalez FJ. Parkinson's disease, pesticides and individual vulnerability. Trends Pharmacol Sci 2004; 25:124-9. [PMID: 15019266 DOI: 10.1016/j.tips.2004.01.007] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Moreno Paolini
- Department of Pharmacology, Alma-Mater Studiorum, The University of Bologna, Via Irnerio, 48-40126 Bologna, Italy.
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McLean AJ, Cogger VC, Chong GC, Warren A, Markus AMA, Dahlstrom JE, Le Couteur DG. Age-related pseudocapillarization of the human liver. J Pathol 2003; 200:112-7. [PMID: 12692849 DOI: 10.1002/path.1328] [Citation(s) in RCA: 110] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Age-related changes in liver function are important because they may promote susceptibility to adverse drug reactions, neurotoxicity, atherosclerosis, and other important diseases in older people. Age-related changes in the rat hepatic sinusoidal endothelium, termed pseudocapillarization, have been described recently and these may contribute to hepatic impairment. The present study has examined surgical and post-mortem specimens with immunohistochemistry and transmission electron microscopy to determine whether pseudocapillarization also occurs in older humans. The age of the subject, independent of systemic disease or hepatic pathology in surgical and post-mortem samples of human liver, was associated with increased peri-sinusoidal expression of von Willebrand's factor, collagen I, collagen IV, and staining with Masson's trichrome. Electron microscopy revealed significant age-related thickening of the sinusoidal endothelium (young 165 +/- 17 nm, middle age 222 +/- 11 nm, older 289 +/- 9 nm, p < 0.001) with loss of fenestrations (young 7.7 +/- 0.7 per 10 micro m, middle age 3.6 +/- 0.5 per 10 micro m, older 1.5 +/- 0.4 per 10 micro m, p < 0.001), and age-related deposition of basal lamina and collagen. In conclusion, ageing in humans is associated with morphological changes in the sinusoidal endothelium and space of Disse which are presumptively related to the ageing process and potentially represent an important link between the ageing process and disease susceptibility.
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Affiliation(s)
- Allan J McLean
- National Ageing Research Institute and the Department of Medicine, University of Melbourne and the Royal Melbourne Hospital, Parkville, Australia.
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