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Weinreb O, Mandel S, Youdim MBH, Amit T. Targeting dysregulation of brain iron homeostasis in Parkinson's disease by iron chelators. Free Radic Biol Med 2013; 62:52-64. [PMID: 23376471 DOI: 10.1016/j.freeradbiomed.2013.01.017] [Citation(s) in RCA: 145] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Revised: 01/09/2013] [Accepted: 01/14/2013] [Indexed: 10/27/2022]
Abstract
Brain iron accumulation has been implicated in a host of chronic neurological diseases, including Parkinson's disease (PD). The elevated iron levels observed in the substantia nigra of PD subjects have been suggested to incite the generation of reactive oxygen species and intracellular α-synuclein aggregation, terminating in the oxidative neuronal destruction of this brain area. Thus, elucidation of the molecular mechanisms involved in iron dysregulation and oxidative stress-induced neurodegeneration is a crucial step in deciphering PD pathology and in developing novel iron-complexing compounds aimed at restoring brain iron homeostasis and attenuating neurodegeneration. This review discusses the involvement of dysregulation of brain iron homeostasis in PD pathology, with an emphasis on the potential effectiveness of naturally occurring compounds and novel iron-chelating/antioxidant therapeutic hybrid molecules, exerting a spectrum of neuroprotective interrelated activities: antioxidant/monoamine oxidase inhibition, activation of the hypoxia-inducible factor (HIF)-1 signaling pathway, induction of HIF-1 target iron-regulatory and antioxidative genes, and inhibition of α-synuclein accumulation and aggregation.
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Affiliation(s)
- Orly Weinreb
- Eve Topf Centers of Excellence for Neurodegenerative Diseases Research, Department of Pharmacology, Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel.
| | - Silvia Mandel
- Eve Topf Centers of Excellence for Neurodegenerative Diseases Research, Department of Pharmacology, Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
| | - Moussa B H Youdim
- Eve Topf Centers of Excellence for Neurodegenerative Diseases Research, Department of Pharmacology, Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
| | - Tamar Amit
- Eve Topf Centers of Excellence for Neurodegenerative Diseases Research, Department of Pharmacology, Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
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252
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Perfeito R, Cunha-Oliveira T, Rego AC. Reprint of: revisiting oxidative stress and mitochondrial dysfunction in the pathogenesis of Parkinson disease-resemblance to the effect of amphetamine drugs of abuse. Free Radic Biol Med 2013; 62:186-201. [PMID: 23743292 DOI: 10.1016/j.freeradbiomed.2013.05.042] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Revised: 08/15/2012] [Accepted: 08/16/2012] [Indexed: 12/15/2022]
Abstract
Parkinson disease (PD) is a chronic and progressive neurological disease associated with a loss of dopaminergic neurons. In most cases the disease is sporadic but genetically inherited cases also exist. One of the major pathological features of PD is the presence of aggregates that localize in neuronal cytoplasm as Lewy bodies, mainly composed of α-synuclein (α-syn) and ubiquitin. The selective degeneration of dopaminergic neurons suggests that dopamine itself may contribute to the neurodegenerative process in PD. Furthermore, mitochondrial dysfunction and oxidative stress constitute key pathogenic events of this disorder. Thus, in this review we give an actual perspective to classical pathways involving these two mechanisms of neurodegeneration, including the role of dopamine in sporadic and familial PD, as well as in the case of abuse of amphetamine-type drugs. Mutations in genes related to familial PD causing autosomal dominant or recessive forms may also have crucial effects on mitochondrial morphology, function, and oxidative stress. Environmental factors, such as MPTP and rotenone, have been reported to induce selective degeneration of the nigrostriatal pathways leading to α-syn-positive inclusions, possibly by inhibiting mitochondrial complex I of the respiratory chain and subsequently increasing oxidative stress. Recently, increased risk for PD was found in amphetamine users. Amphetamine drugs have effects similar to those of other environmental factors for PD, because long-term exposure to these drugs leads to dopamine depletion. Moreover, amphetamine neurotoxicity involves α-syn aggregation, mitochondrial dysfunction, and oxidative stress. Therefore, dopamine and related oxidative stress, as well as mitochondrial dysfunction, seem to be common links between PD and amphetamine neurotoxicity.
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Affiliation(s)
- Rita Perfeito
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Teresa Cunha-Oliveira
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Ana Cristina Rego
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; Faculty of Medicine, University of Coimbra, 3004-504 Coimbra, Portugal.
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253
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Garcia-Garcia A, Anandhan A, Burns M, Chen H, Zhou Y, Franco R. Impairment of Atg5-dependent autophagic flux promotes paraquat- and MPP⁺-induced apoptosis but not rotenone or 6-hydroxydopamine toxicity. Toxicol Sci 2013; 136:166-82. [PMID: 23997112 DOI: 10.1093/toxsci/kft188] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Controversial reports on the role of autophagy as a survival or cell death mechanism in dopaminergic cell death induced by parkinsonian toxins exist. We investigated the alterations in autophagic flux and the role of autophagy protein 5 (Atg5)-dependent autophagy in dopaminergic cell death induced by parkinsonian toxins. Dopaminergic cell death induced by the mitochondrial complex I inhibitors 1-methyl-4-phenylpyridinium (MPP⁺) and rotenone, the pesticide paraquat, and the dopamine analog 6-hydroxydopamine (6-OHDA) was paralleled by increased autophagosome accumulation. However, when compared with basal autophagy levels using chloroquine, autophagosome accumulation was a result of impaired autophagic flux. Only 6-OHDA induced an increase in autophagosome formation. Overexpression of a dominant negative form of Atg5 increased paraquat- and MPP⁺-induced cell death. Stimulation of mammalian target of rapamycin (mTOR)-dependent signaling protected against cell death induced by paraquat, whereas MPP⁺-induced toxicity was enhanced by wortmannin, a phosphoinositide 3-kinase class III inhibitor, rapamycin, and trehalose, an mTOR-independent autophagy activator. Modulation of autophagy by either pharmacological or genetic approaches had no effect on rotenone or 6-OHDA toxicity. Cell death induced by parkinsonian neurotoxins was inhibited by the pan caspase inhibitor (Z-VAD), but only caspase-3 inhibition was able to decrease MPP⁺-induced cell death. Finally, inhibition of the lysosomal hydrolases, cathepsins, increased the toxicity by paraquat and MPP⁺, supporting a protective role of Atg5-dependent autophagy and lysosomes degradation pathways on dopaminegic cell death. These results demonstrate that in dopaminergic cells, Atg5-dependent autophagy acts as a protective mechanism during apoptotic cell death induced by paraquat and MPP⁺ but not during rotenone or 6-OHDA toxicity.
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254
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Dominguez-Meijide A, Villar-Cheda B, Garrido-Gil P, Sierrra-Paredes G, Guerra MJ, Labandeira-Garcia JL. Effect of chronic treatment with angiotensin type 1 receptor antagonists on striatal dopamine levels in normal rats and in a rat model of Parkinson's disease treated with L-DOPA. Neuropharmacology 2013; 76 Pt A:156-68. [PMID: 23973568 DOI: 10.1016/j.neuropharm.2013.07.016] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 06/20/2013] [Accepted: 07/17/2013] [Indexed: 01/08/2023]
Abstract
Beneficial effects of angiotensin type-1 receptor (AT1) inhibition have been observed in a number of brain processes mediated by oxidative stress and neuroinflammation, including Parkinson's disease. However, important counterregulatory interactions between dopamine and angiotensin systems have recently been demonstrated in several peripheral tissues, and it is possible that a decrease in dopamine levels due to AT1 inhibition may interfere with neuroprotective strategies. The present experiments involving rats with normal dopaminergic innervation indicate that chronic treatment with the AT1 antagonist candesartan does not significantly affect striatal levels of dopamine, serotonin or metabolites, as does not significantly affect motor behavior, as evaluated by the rotarod test. Interestingly, chronic administration of candesartan to normal rats induced a marked increase in dopamine D1 and a decrease in dopamine D2 receptor expression. In a rat model of Parkinson's disease treated with L-DOPA, no differences in striatal dopamine and serotonin levels were observed between candesartan-treated rats and untreated, which suggests that chronic treatment with candesartan does not significantly affect the process of L-DOPA decarboxylation and dopamine release in Parkinson's disease patients. Candesartan did not induce any differences in the striatal expression of dopamine D1 and D2 and serotonin 5-HT1B receptors in 6ydroxydopamine-lesioned rats treated with L-DOPA. The results suggest that chronic treatment with AT1 antagonists as a neuroprotective strategy does not significantly affect striatal dopamine release or motor behavior. This article is part of the Special Issue entitled 'The Synaptic Basis of Neurodegenerative Disorders'.
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Affiliation(s)
- Antonio Dominguez-Meijide
- Laboratory of Neuroanatomy and Experimental Neurology, Department of Morphological Sciences, Faculty of Medicine, University of Santiago de Compostela, Santiago de Compostela, Spain; Networking Research Center on Neurodegenerative Diseases (CIBERNED), Spain
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255
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Riahi G, Morissette M, Samadi P, Parent M, Di Paolo T. Basal ganglia serotonin 1B receptors in parkinsonian monkeys with L-DOPA-induced dyskinesia. Biochem Pharmacol 2013; 86:970-8. [PMID: 23954709 DOI: 10.1016/j.bcp.2013.08.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Revised: 08/02/2013] [Accepted: 08/05/2013] [Indexed: 01/03/2023]
Abstract
L-DOPA-induced dyskinesias (LID)s are abnormal involuntary movements limiting the chronic use of L-DOPA, the main pharmacological treatment of Parkinson's disease (PD). Serotonin receptors are thought to contribute to LID but serotonin 1B (5-HT1B) receptors have never been investigated in any primate models of PD and LID. Therefore, we measured 5-HT1B receptors with [(3)H]GR 125743 autoradiography in controls, MPTP-lesioned monkeys, and L-DOPA-treated MPTP monkeys, with or without Ro 61-8048 treatment, a kynurenine hydroxylase inhibitor alleviating LID. In normal condition, 5-HT1B receptor specific binding was highest in the substantia nigra pars reticulata (SNr), high in the globus pallidus (GP), nucleus accumbens and substantia innominata and lower in the caudate nucleus and putamen. 5-HT1B receptors were increased in caudate nucleus, putamen and SNr of MPTP monkeys compared to controls. L-DOPA-treated MPTP monkeys had elevated 5-HT1B receptor specific binding in caudate nucleus, putamen, SNr and internal GP. In all these brain regions, increases were prevented by co-administration of Ro 61-8048. No effect of MPTP lesion or treatment was observed for 5-HT1B specific binding in the external GP, nucleus accumbens and substantia innominata. This study is the first description in primates of altered brain 5-HT1B receptors associated with prevention of LID.
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Affiliation(s)
- Golnasim Riahi
- Faculty of Pharmacy, Université Laval, Quebec City, Canada, G1K 7P4; Neuroscience Research Unit, Centre de recherche du CHU de Québec, Quebec City, Canada, G1V 4G2; Centre de Recherche de l'Institut universitaire en santé mentale de Québec, Quebec City, Canada, G1J 2G3
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256
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Plowman EK, Maling N, Thomas NJ, Fowler SC, Kleim JA. Targeted motor rehabilitation dissociates corticobulbar versus corticospinal dysfunction in an animal model of Parkinson's disease. Neurorehabil Neural Repair 2013; 28:85-95. [PMID: 23921422 DOI: 10.1177/1545968313498648] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Recent evidence suggests that motor training may be beneficial for slowing the onset of motor impairments in Parkinson's disease (PD). OBJECTIVE To examine the impact of targeted rehabilitation on limb motor and cranial motor function and the corresponding corticospinal and corticobulbar circuits in a rodent model of PD. METHODS Baseline performance of limb (reaching) and cranial (licking) motor function were established prior to and 6 weeks following unilateral intrastriatal 6-hydroxydopamine (6-OHDA) infusions. Animals then received 6 weeks of limb motor rehabilitation (LMR) or cranial motor rehabilitation (CMR), after which motor performance was reassessed. Intracortical microstimulation (ICMS) was used to generate motor maps of corresponding corticospinal (forelimb) and corticobulbar (tongue) movement representations within the motor cortex ipsilateral to the 6-OHDA infusion. Quantitative tyrosine hydroxylase (TH) immunohistochemistry was performed to determine levels of striatal TH depletion in 6-OHDA animals using near infrared densitometry. RESULTS (1) unilateral intrastriatal dopamine depletion impaired both reaching accuracy and lick force; (2) targeted LMR ameliorated impairments in reaching performance; however, CMR did not improve lick force impairments; (3) unilateral dopamine depletion significantly reduced forelimb but not tongue motor map topography; (4) LMR partially restored forelimb motor maps, whereas CMR did not alter tongue motor maps; and (5) significant correlations were observed between skilled reaching accuracy, forelimb motor map area, and TH depletion, but no relationships were revealed for cranial motor function, motor maps, or TH depletion. CONCLUSIONS These data demonstrate dissociation between striatal dopamine depletion, limb versus cranial motor function, and targeted motor rehabilitation in a rodent model of PD.
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257
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Wang HM, Zhang T, Li Q, Huang JK, Chen RF, Sun XJ. Inhibition of glycogen synthase kinase-3β by lithium chloride suppresses 6-hydroxydopamine-induced inflammatory response in primary cultured astrocytes. Neurochem Int 2013; 63:345-53. [PMID: 23871716 DOI: 10.1016/j.neuint.2013.07.003] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Revised: 06/29/2013] [Accepted: 07/07/2013] [Indexed: 11/21/2022]
Abstract
An increasing amount of evidence has emerged to suggest that neuroinflammatory process is involved in the pathogenesis of Parkinson's disease (PD). Activated microglia and astrocytes are found in the substantia nigra (SN) of Parkinson's disease brains as well as in animal models of Parkinson's disease. Although reactive astrocytes are involved in the progression of PD, the role of reactive astrocytes in neuroinflammation of PD has received limited attention to date. Recently, Glycogen synthase kinase-3β (GSK-3β) was identified as a crucial regulator of the inflammatory response. The purpose of this study was to explore the mechanism by which 6-hydroxydopamine (6-OHDA) induces inflammatory response in astrocytes and observe the anti-inflammatory effect of lithium chloride (LiCl) on 6-OHDA-treated astrocytes. In the present study, we found that glial fibrillary acidic protein (GFAP) was markedly upregulated in the presence of 6-OHDA. Moreover, our results revealed that proinflammatory molecules including inducible nitric oxide synthase (iNOS), nitric oxide (NO), cyclooxygenase-2(COX-2), prostaglandins E2 (PGE2), and tumor necrosis factor-α (TNF-α) were obviously increased in astrocytes exposed to 6-OHDA. Western blot analysis revealed that 6-OHDA significantly increased dephosphorylation/activation of GSK-3β as well as the nuclear translocation of nuclear factor-κB (NF-κB) p65. Besides, GSK-3β inhibitor LiCl and SB415286 inhibited the GSK-3β/NF-κB signaling pathway, leading to the reduction of proinflammatory molecules in 6-OHDA-activated astrocytes. These results confirmed that GSK-3β inhibitor LiCl and SB415286 provide protection against neuroinflammation in 6-OHDA-treated astrocytes. Therefore, GSK-3β may be a potential therapeutic target for the treatment of PD.
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258
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Villalba RM, Smith Y. Differential striatal spine pathology in Parkinson's disease and cocaine addiction: a key role of dopamine? Neuroscience 2013; 251:2-20. [PMID: 23867772 DOI: 10.1016/j.neuroscience.2013.07.011] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Accepted: 07/03/2013] [Indexed: 01/19/2023]
Abstract
In the striatum, the dendritic tree of the two main populations of projection neurons, called "medium spiny neurons (MSNs)", are covered with spines that receive glutamatergic inputs from the cerebral cortex and thalamus. In Parkinson's disease (PD), striatal MSNs undergo an important loss of dendritic spines, whereas aberrant overgrowth of striatal spines occurs following chronic cocaine exposure. This review examines the possibility that opposite dopamine dysregulation is one of the key factors that underlies these structural changes. In PD, nigrostriatal dopamine degeneration results in a significant loss of dendritic spines in the dorsal striatum, while rodents chronically exposed to cocaine and other psychostimulants, display an increase in the density of "thin and immature" spines in the nucleus accumbens (NAc). In rodent models of PD, there is evidence that D2 dopamine receptor-containing MSNs are preferentially affected, while D1-positive cells are the main targets of increased spine density in models of addiction. However, such specificity remains to be established in primates. Although the link between the extent of striatal spine changes and the behavioral deficits associated with these disorders remains controversial, there is unequivocal evidence that glutamatergic synaptic transmission is significantly altered in both diseased conditions. Recent studies have suggested that opposite calcium-mediated regulation of the transcription factor myocyte enhancer factor 2 (MEF2) function induces these structural defects. In conclusion, there is strong evidence that dopamine is a major, but not the sole, regulator of striatal spine pathology in PD and addiction to psychostimulants. Further studies of the role of glutamate and other genes associated with spine plasticity in mediating these effects are warranted.
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Affiliation(s)
- R M Villalba
- Yerkes National Primate Research Center, Emory University, 954, Gatewood Road NE, Atlanta, GA 30329, USA; UDALL Center of Excellence for Parkinson's Disease, Emory University, 954, Gatewood Road NE, Atlanta, GA 30329, USA.
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259
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Stankiewicz TR, Schroeder EK, Kelsey NA, Bouchard RJ, Linseman DA. C-terminal binding proteins are essential pro-survival factors that undergo caspase-dependent downregulation during neuronal apoptosis. Mol Cell Neurosci 2013; 56:322-332. [PMID: 23859824 DOI: 10.1016/j.mcn.2013.07.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2013] [Revised: 06/25/2013] [Accepted: 07/08/2013] [Indexed: 12/20/2022] Open
Abstract
C-terminal binding proteins (CtBPs) are transcriptional co-repressors that are subject to proteasome-dependent downregulation during apoptosis. Alternative mechanisms that regulate CtBP expression are currently under investigation and the role of CtBPs in neuronal survival is largely unexplored. Here, we show that CtBPs are downregulated in cerebellar granule neurons (CGNs) induced to undergo apoptosis by a variety of stressors. Moreover, antisense-mediated downregulation of CtBP1 is sufficient to cause CGN apoptosis. Similarly, the CtBP inhibitor, 4-methylthio-2-oxobutyric acid, induces expression of the CtBP target Noxa and causes actinomycin-sensitive CGN apoptosis. Unexpectedly, we found that the mechanism of CtBP downregulation in CGNs undergoing apoptosis varies in a stimulus-specific manner involving either the proteasome or caspases. In the case of CGNs deprived of depolarizing potassium (5K apoptotic condition), caspases appear to play a dominant role in CtBP downregulation. However, incubation in 5K does not enhance the kinetics of CtBP1 degradation and recombinant CtBP1 is not cleaved in vitro by caspase-3. In addition, 5K has no significant effect on CtBP transcript expression. Finally, mouse embryonic stem cells display caspase-dependent downregulation of CtBP1 following exposure to staurosporine, an effect that is not observed in DGCR8 knockout cells which are deficient in miRNA processing. These data identify caspase-dependent downregulation of CtBPs as an alternative mechanism to the proteasome for regulation of these transcriptional co-repressors in neurons undergoing apoptosis. Moreover, caspases appear to regulate CtBP expression indirectly, at a post-transcriptional level, and via a mechanism that is dependent upon miRNA processing. We conclude that CtBPs are essential pro-survival proteins in neurons and their downregulation contributes significantly to neuronal apoptosis via the de-repression of pro-apoptotic genes.
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Affiliation(s)
- Trisha R Stankiewicz
- Research Service, Veterans Affairs Medical Center, Denver, Colorado, 80220, USA.,Department of Biological Sciences and Eleanor Roosevelt Institute, University of Denver, Denver, Colorado, 80208, USA
| | - Emily K Schroeder
- Research Service, Veterans Affairs Medical Center, Denver, Colorado, 80220, USA
| | - Natalie A Kelsey
- Department of Biological Sciences and Eleanor Roosevelt Institute, University of Denver, Denver, Colorado, 80208, USA
| | - Ron J Bouchard
- Research Service, Veterans Affairs Medical Center, Denver, Colorado, 80220, USA
| | - Daniel A Linseman
- Research Service, Veterans Affairs Medical Center, Denver, Colorado, 80220, USA.,Department of Biological Sciences and Eleanor Roosevelt Institute, University of Denver, Denver, Colorado, 80208, USA.,Division of Clinical Pharmacology and Toxicology, Department of Medicine and Neuroscience Program, University of Colorado School of Medicine, Aurora, Colorado, 80045, USA
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260
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Garbayo E, Ansorena E, Blanco-Prieto MJ. Drug development in Parkinson's disease: from emerging molecules to innovative drug delivery systems. Maturitas 2013; 76:272-8. [PMID: 23827471 DOI: 10.1016/j.maturitas.2013.05.019] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 05/29/2013] [Indexed: 12/23/2022]
Abstract
Current treatments for Parkinson's disease (PD) are aimed at addressing motor symptoms but there is no therapy focused on modifying the course of the disease. Successful treatment strategies have been so far limited and brain drug delivery remains a major challenge that restricts its treatment. This review provides an overview of the most promising emerging agents in the field of PD drug discovery, discussing improvements that have been made in brain drug delivery for PD. It will be shown that new approaches able to extend the length of the treatment, to release the drug in a continuous manner or to cross the blood-brain barrier and target a specific region are still needed. Overall, the results reviewed here show that there is an urgent need to develop both symptomatic and disease-modifying treatments, giving priority to neuroprotective treatments. Promising perspectives are being provided in this field by rasagiline and by neurotrophic factors like glial cell line-derived neurotrophic factor. The identification of disease-relevant genes has also encouraged the search for disease-modifying therapies that function by identifying molecularly targeted drugs. The advent of new molecular and cellular targets like α-synuclein, leucine-rich repeat serine/threonine protein kinase 2 or parkin, among others, will require innovative delivery therapies. In this regard, drug delivery systems (DDS) have shown great potential for improving the efficacy of conventional and new PD therapy and reducing its side effects. The new DDS discussed here, which include microparticles, nanoparticles and hydrogels among others, will probably open up possibilities that extend beyond symptomatic relief. However, further work needs to be done before DDS become a therapeutic option for PD patients.
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Affiliation(s)
- E Garbayo
- Pharmacy and Pharmaceutical Technology Department, University of Navarra, Pamplona, Spain
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261
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Zhang J, Niu N, Wang M, McNutt MA, Zhang D, Zhang B, Lu S, Liu Y, Liu Z. Neuron-derived IgG protects dopaminergic neurons from insult by 6-OHDA and activates microglia through the FcγR I and TLR4 pathways. Int J Biochem Cell Biol 2013; 45:1911-20. [PMID: 23791745 DOI: 10.1016/j.biocel.2013.06.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Revised: 05/24/2013] [Accepted: 06/03/2013] [Indexed: 12/09/2022]
Abstract
Oxidative and immune attacks from the environment or microglia have been implicated in the loss of dopaminergic neurons of Parkinson's disease. The role of IgG which is an important immunologic molecule in the process of Parkinson's disease has been unclear. Evidence suggests that IgG can be produced by neurons in addition to its traditionally recognized source B lymphocytes, but its function in neurons is poorly understood. In this study, extensive expression of neuron-derived IgG was demonstrated in dopaminergic neurons of human and rat mesencephalon. With an in vitro Parkinson's disease model, we found that neuron-derived IgG can improve the survival and reduce apoptosis of dopaminergic neurons induced by 6-hydroxydopamine toxicity, and also depress the release of NO from microglia triggered by 6-hydroxydopamine. Expression of TNF-α and IL-10 in microglia was elevated to protective levels by neuron-derived IgG at a physiologic level via the FcγR I and TLR4 pathways and microglial activation could be attenuated by IgG blocking. All these data suggested that neuron-derived IgG may exert a self-protective function by activating microglia properly, and IgG may be involved in maintaining immunity homeostasis in the central nervous system and serve as an active factor under pathological conditions such as Parkinson's disease.
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Affiliation(s)
- Jie Zhang
- Department of Human Anatomy, Weifang Medical University, Weifang 261053, China
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262
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Morin N, Morissette M, Grégoire L, Gomez-Mancilla B, Gasparini F, Di Paolo T. Chronic treatment with MPEP, an mGlu5 receptor antagonist, normalizes basal ganglia glutamate neurotransmission in L-DOPA-treated parkinsonian monkeys. Neuropharmacology 2013; 73:216-31. [PMID: 23756168 DOI: 10.1016/j.neuropharm.2013.05.028] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Revised: 05/17/2013] [Accepted: 05/18/2013] [Indexed: 10/26/2022]
Abstract
Metabotropic glutamate 5 (mGlu5) receptor antagonists reduce L-3,4-dihydroxyphenylalanine (L-DOPA)-induced dyskinesias (LID) in Parkinson's disease (PD). The aim of this study was to investigate the long-term effect of the prototypal mGlu5 receptor antagonist 2-methyl-6-(phenylethynyl)pyridine (MPEP) on glutamate receptors known to be involved in the development of LID in the de novo chronic treatment of monkeys lesioned with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). MPTP monkeys were treated for one month with L-DOPA and developed dyskinesias while those treated with L-DOPA and MPEP (10 mg/kg) developed significantly less. Normal control and saline-treated MPTP monkeys were also included. All MPTP monkeys were extensively and similarly denervated. The basal ganglia [(3)H]ABP688 specific binding (mGlu5 receptors) was elevated in L-DOPA-treated MPTP monkeys compared to controls but not in those treated with L-DOPA and MPEP; dyskinesia scores of these monkeys correlated positively with their [(3)H]ABP688 specific binding. Striatal density (B(max)) of [(3)H]ABP688 specific binding increased in L-DOPA-treated MPTP monkeys compared to other groups and affinity (Kd) remained unchanged. Striatal mGlu5 receptor mRNA remained unchanged following treatments. Elevated basal ganglia specific binding of [(3)H]Ro 25-6981 (NMDA NR1/NR2B receptors), [(3)H]Ro 48-8587 (AMPA receptors) but not [(3)H]CGP-39653 (NMDA NR1/NR2A receptors) was observed only in L-DOPA-treated MPTP monkeys; dyskinesias scores correlated with binding. By contrast, basal ganglia [(3)H]LY341495 specific binding (mGlu2/3 receptors) decreased in L-DOPA-treated MPTP monkeys compared to controls, saline and L-DOPA + MPEP treated MPTP monkeys; dyskinesias scores correlated negatively with this binding. Hence, chronic MPEP treatment reduces the development of LID and is associated with a normalization of glutamate neurotransmission.
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Affiliation(s)
- Nicolas Morin
- Neuroscience Research Unit, Laval University Medical Center (CHUQ), Quebec, QC, Canada
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263
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Worlitzer MMA, Viel T, Jacobs AH, Schwamborn JC. The majority of newly generated cells in the adult mouse substantia nigra express low levels of Doublecortin, but their proliferation is unaffected by 6-OHDA-induced nigral lesion or Minocycline-mediated inhibition of neuroinflammation. Eur J Neurosci 2013; 38:2684-92. [PMID: 23734736 DOI: 10.1111/ejn.12269] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Revised: 04/28/2013] [Accepted: 04/30/2013] [Indexed: 11/29/2022]
Abstract
Parkinson's disease is characterized by a selective loss of dopaminergic neurons in the substantia nigra (SN). However, whether regenerative endogenous neurogenesis is taking place in the mammalian SN of parkinsonian and non-parkinsonian brains remains of debate. Here, we tested whether proliferating cells in the SN and their neurogenic potential would be affected by anti-inflammatory treatment under physiological conditions and in the 6-hydroxy-dopamine (6-OHDA) Parkinson's disease mouse model. We report that the majority of newly generated nigral cells are positive for Doublecortin (Dcx), which is an often used marker for neural progenitor cells. Yet, Dcx expression levels in these cells were much lower than in neural progenitor cells of the subventricular zone and the dentate gyrus neural progenitor cells. Furthermore, these newly generated nigral cells are negative for neuronal lineage markers such as TuJ1 and NeuN. Therefore, their neuronal commitment is questionable. Instead, we found evidence for oligodendrogenesis and astrogliosis in the SN. Finally, neither short-term nor long-term inhibition of neuroinflammation by Minocycline- or 6-OHDA-induced lesion affected the numbers of newly generated cells in our disease paradigm. Our findings of adult generated Dcx(+) cells in the SN add important data for understanding the cellular composition and consequently the regenerative capacity of the SN.
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Affiliation(s)
- Maik M A Worlitzer
- Institute of Cell Biology, Stem Cell Biology and Regeneration Group, Münster, Germany
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Bhide N, Lindenbach D, Surrena MA, Goldenberg AA, Bishop C, Berger SP, Paquette MA. The effects of BMY-14802 against L-DOPA- and dopamine agonist-induced dyskinesia in the hemiparkinsonian rat. Psychopharmacology (Berl) 2013; 227:533-44. [PMID: 23389756 PMCID: PMC3657017 DOI: 10.1007/s00213-013-3001-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Accepted: 01/11/2013] [Indexed: 12/18/2022]
Abstract
RATIONALE L-DOPA continues to be the primary treatment for patients with Parkinson's disease; however, the benefits of long-term treatment are often accompanied by debilitating side effects known as dyskinesias. In recent years, several 5-HT1A receptor agonists have been found to reduce dyskinesia in clinical and experimental models of PD. The purported sigma-1 antagonist, BMY-14802 has been previously demonstrated to reduce L-DOPA induced dyskinesia in a 5-HT1A receptor dependent manner. OBJECTIVE In the present study, we extend these findings by examining the anti-dyskinetic potential of BMY-14802 against L-DOPA, the D1 receptor agonist SKF81297 and the D2 receptor agonist, quinpirole, in the hemi-parkinsonian rat model. In addition, the receptor specificity of BMY-14802's effects was evaluated using WAY-100635, a 5-HT1A receptor antagonist. RESULTS Results confirmed the dose-dependent (20 > 10 > 5 mg/kg) anti-dyskinetic effects of BMY-14802 against L-DOPA with preservation of anti-parkinsonian efficacy at 10 mg/kg. BMY-14802 at 10 and 20 mg/kg also reduced dyskinesia induced by both D1 and D2 receptor agonists. Additionally, BMY-14802's anti-dyskinetic effects against L-DOPA, but not SKF81297 or quinpirole, were reversed by WAY-100635 (0.5 mg/kg). CONCLUSION Collectively, these findings demonstrate that BMY-14802 provides anti-dyskinetic relief against L-DOPA and direct DA agonist in a preclinical model of PD, acting via multiple receptor systems and supports the utility of such compounds for the improved treatment of PD.
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Affiliation(s)
- Nirmal Bhide
- Behavioral Neuroscience Program, Department of Psychology, Binghamton University, Binghamton, NY 13902-6000, USA
| | - David Lindenbach
- Behavioral Neuroscience Program, Department of Psychology, Binghamton University, Binghamton, NY 13902-6000, USA
| | - Margaret A. Surrena
- Behavioral Neuroscience Program, Department of Psychology, Binghamton University, Binghamton, NY 13902-6000, USA
| | - Adam A. Goldenberg
- Behavioral Neuroscience Program, Department of Psychology, Binghamton University, Binghamton, NY 13902-6000, USA
| | - Christopher Bishop
- Behavioral Neuroscience Program, Department of Psychology, Binghamton University, Binghamton, NY 13902-6000, USA
| | - S. Paul Berger
- Department of Veterans Affairs Medical Center, Portland, OR 97239
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265
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Petri D, Pum M, Vesper J, Huston JP, Schnitzler A. GABAA-receptor activation in the subthalamic nucleus compensates behavioral asymmetries in the hemiparkinsonian rat. Behav Brain Res 2013; 252:58-67. [PMID: 23727148 DOI: 10.1016/j.bbr.2013.05.044] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 05/22/2013] [Indexed: 01/22/2023]
Abstract
The subthalamic nucleus (STN) has a pivotal role in the pathophysiology of Parkinson's disease (PD). Modulation of STN activity (by lesions, pharmacological or electrical stimulation) has been shown to improve motor parameters in PD patients and in animal models of PD. In an attempt to characterize the neurochemical bases for such antiparkinsonian action, we address specific neurotransmitter systems via local pharmacological manipulation of the STN in hemiparkinsonian rats. Here, we have focused on the GABAergic and glutamatergic receptors in the STN. In animals with unilateral 6-hydroxydopamine lesions of the nigro-striatal tract, we administered either the selective GABAA-agonist muscimol (0.5 μg and 1.0 μg), the non-competitive N-methyl-d-aspartate (NMDA)-antagonist MK-801 (dizocilpine; 2.5 μg), or vehicle (0.25 μl) into the STN. The effects of GABAergic and glutamatergic modulation of the STN on motor parameters were assessed by gauging rotational behavior and locomotion. Application of muscimol ipsilateral to the side of dopamine-depletion influenced turning behavior in a dose-dependent fashion, with the low dose re-adjusting turning behavior to a non-biased distribution, and the high dose evoking contraversive turning. The administration of MK-801 did not have such effects. These findings give evidence for the involvement of GABAergic activation in the STN in the compensation of motor asymmetries in the hemiparkinsonian rat, whereas N-methyl-d-aspartate (NMDA)-antagonism was ineffective in this model of PD.
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Affiliation(s)
- David Petri
- Center for Behavioral Neuroscience, Heinrich-Heine-University, D-40225 Düsseldorf, Germany
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266
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Harrison IF, Dexter DT. Epigenetic targeting of histone deacetylase: therapeutic potential in Parkinson's disease? Pharmacol Ther 2013; 140:34-52. [PMID: 23711791 DOI: 10.1016/j.pharmthera.2013.05.010] [Citation(s) in RCA: 150] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Accepted: 05/09/2013] [Indexed: 12/12/2022]
Abstract
Parkinson's disease (PD) is the most common movement disorder affecting more than 4million people worldwide. The primary motor symptoms of the disease are due to degeneration of dopaminergic nigrostriatal neurons. Dopamine replacement therapies have therefore revolutionised disease management by partially controlling these symptoms. However these drugs can produce debilitating side effects when used long term and do not protect degenerating neurons against death. Recent evidence has highlighted a pathological imbalance in PD between the acetylation and deacetylation of the histone proteins around which deoxyribonucleic acid (DNA) is coiled, in favour of excessive histone deacetylation. This mechanism of adding/removing acetyl groups to histone lysine residues is one of many epigenetic regulatory processes which control the expression of genes, many of which will be essential for neuronal survival. Hence, such epigenetic modifications may have a pathogenic role in PD. It has therefore been hypothesised that if this pathological imbalance can be corrected with the use of histone deacetylase inhibiting agents then neurodegeneration observed in PD can be ameliorated. This article will review the current literature with regard to epigenetic changes in PD and the use of histone deacetylase inhibitors (HDACIs) in PD: examining the evidence of the neuroprotective effects of numerous HDACIs in cellular and animal models of Parkinsonian cell death. Ultimately answering the question: does epigenetic targeting of histone deacetylases hold therapeutic potential in PD?
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Affiliation(s)
- Ian F Harrison
- Parkinson's Disease Research Group, Centre for Neuroinflammation and Neurodegeneration, Division of Brain Sciences, Department of Medicine, Imperial College London, Hammersmith Hospital Campus, London W12 0NN, UK.
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Herzog CD, Brown L, Kruegel BR, Wilson A, Tansey MG, Gage FH, Johnson EM, Bartus RT. Enhanced neurotrophic distribution, cell signaling and neuroprotection following substantia nigral versus striatal delivery of AAV2-NRTN (CERE-120). Neurobiol Dis 2013; 58:38-48. [PMID: 23631873 DOI: 10.1016/j.nbd.2013.04.011] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Revised: 03/29/2013] [Accepted: 04/18/2013] [Indexed: 11/18/2022] Open
Abstract
This paper reassesses the currently accepted viewpoint that targeting the terminal fields (i.e. striatum) of degenerating nigrostriatal dopamine neurons with neurotrophic factors in Parkinson's disease (PD) is sufficient for achieving an optimal neurotrophic response. Recent insight indicating that PD is an axonopathy characterized by axonal transport deficits prompted this effort. We tested whether a significantly greater neurotrophic response might be induced in SN neurons when the neurotrophic factor neurturin (NRTN) is also targeted to the substantia nigra (SN), compared to the more conventional, striatum-only target. While recognizing the importance of maintaining the integrity of nigrostriatal fibers and terminals (especially for achieving optimal function), we refocused attention to the fate of SN neurons. Under conditions of axonal degeneration and neuronal transport deficits, this component of the nigrostriatal system is most vulnerable to the lack of neurotrophic exposure following striatal-only delivery. Given the location of repair genes induced by neurotrophic factors, achieving adequate neurotrophic exposure to the SN neurons is essential for an optimal neurotrophic response, while the survival of these neurons is essential to the very survival of the fibers. Two separate studies were performed using the 6-OHDA model of nigrostriatal degeneration, in conjunction with delivery of the viral vector AAV2-NRTN (CERE-120) to continuously express NRTN to either striatum or nigra alone or combined striatal/nigral exposure, including conditions of ongoing axonopathy. These studies provide additional insight for reinterpreting past animal neurotrophic/6-OHDA studies conducted under conditions where axon transport deficiencies were generally not accounted for, which suggested that targeting the striatum was both necessary and sufficient. The current data demonstrate that delivering NRTN directly to the SN produces 1) expanded NRTN distribution within the terminal field and cell bodies of targeted nigrostriatal neurons, 2) enhanced intracellular neurotrophic factor signaling in the nigrostriatal neurons, and 3) produced greater numbers of surviving dopamine neurons against 6-OHDA-induced toxicity, particularly under the conditions of active axonopathy. Thus, these data provide empirical support that targeting the SN with neurotrophic factors (in addition to striatum) may help enhance the neurotrophic response in midbrain neurons, particularly under conditions of active neurodegeneration which occurs in PD patients.
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268
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Silva MD, Glaus C, Hesterman JY, Hoppin J, Puppa GHD, Kazules T, Orcutt KM, Germino M, Immke D, Miller S. Regional, kinetic [(18)F]FDG PET imaging of a unilateral Parkinsonian animal model. Am J Nucl Med Mol Imaging 2013; 3:129-141. [PMID: 23526185 PMCID: PMC3601473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 08/12/2012] [Accepted: 02/06/2013] [Indexed: 06/02/2023]
Abstract
Positron emission tomography (PET) imaging with the glucose analog 2-deoxy-2-[(18)F]fluoro-D-glucose ([(18)F] FDG) has demonstrated clinical utility for the monitoring of brain glucose metabolism alteration in progressive neurodegenerative diseases. We examined dynamic [(18)F]FDG PET imaging and kinetic modeling of atlas-based regions to evaluate regional changes in the cerebral metabolic rate of glucose in the widely-used 6-hydroxydopamine (6-OHDA) rat model of Parkinson's disease. Following a bolus injection of 18.5 ± 1 MBq [(18)F]FDG and a 60-minute PET scan, image-derived input functions from the vena cava and left ventricle were used with three models, including Patlak graphical analysis, to estimate the influx constant and the metabolic rate in ten brain regions. We observed statistically significant changes in [(18)F]FDG uptake ipsilateral to the 6-OHDA injection in the basal ganglia, olfactory bulb, and amygdala regions; and these changes are of biological relevance to the disease. These experiments provide further validation for the use of [(18)F]FDG PET imaging in this model for drug discovery and development.
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Affiliation(s)
- Matthew D Silva
- Department of Research Imaging Sciences, Amgen Inc.Thousand Oaks, CA
| | - Charles Glaus
- Department of Research Imaging Sciences, Amgen Inc.Thousand Oaks, CA
| | | | | | | | - Timothy Kazules
- Department of Research Imaging Sciences, Amgen Inc.Thousand Oaks, CA
| | | | | | - David Immke
- Department of Neuroscience, Amgen Inc.Thousand Oaks, CA
| | - Silke Miller
- Department of Neuroscience, Amgen Inc.Thousand Oaks, CA
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Szot P, Franklin A, Sikkema C, Wilkinson CW, Raskind MA. Sequential Loss of LC Noradrenergic and Dopaminergic Neurons Results in a Correlation of Dopaminergic Neuronal Number to Striatal Dopamine Concentration. Front Pharmacol 2012; 3:184. [PMID: 23129999 PMCID: PMC3487487 DOI: 10.3389/fphar.2012.00184] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Accepted: 10/02/2012] [Indexed: 11/17/2022] Open
Abstract
Noradrenergic neurons in the locus coeruleus (LC) are significantly reduced in Parkinson’s disease (PD) and the LC exhibits neuropathological changes early in the disease process. It has been suggested that a loss of LC neurons can enhance the susceptibility of dopaminergic neurons to damage. To determine if LC noradrenergic innervation protects dopaminergic neurons from damage, the dopaminergic neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) was administered to adult male C57Bl/6 mice 3 days after bilateral LC administration of 6-hydroxydopamine (6OHDA), a time when there is a significant reduction in LC neuronal number and innervation to forebrain regions. To assess if LC loss can affect dopaminergic loss four groups of animals were studied: control, 6OHDA, MPTP, and 6OHDA + MPTP; animals sacrificed 3 weeks after MPTP administration. The number of dopaminergic neurons in the substantia nigra (SN) and ventral tegmental area (VTA), and noradrenergic neurons in the LC were determined. Catecholamine levels in striatum were measured by high-pressure liquid chromatography. The loss of LC neurons did not affect the number of dopaminergic neurons in the SN and VTA compared to control; however, LC 6OHDA significantly reduced striatal dopamine (DA; 29% reduced) but not norepinephrine (NE) concentration. MPTP significantly reduced SN and VTA neuronal number and DA concentration in the striatum compared to control; however, there was not a correlation of striatal DA concentration with SN or VTA neuronal number. Administration of 6OHDA prior to MPTP did not enhance MPTP-induced damage despite an effect of LC loss on striatal DA concentration. However, the loss of LC neurons before MPTP resulted now in a correlation between SN and VTA neuronal number to striatal DA concentration. These results demonstrate that the loss of either LC or DA neurons can affect the function of each others systems, indicating the importance of both the noradrenergic and dopaminergic system in PD.
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Affiliation(s)
- Patricia Szot
- Mental Illness Research, Education and Clinical Center, Veterans Administration Puget Sound Health Care System Seattle, WA, USA ; Department of Psychiatry and Behavioral Sciences, University of Washington Seattle, WA, USA
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Healy-Stoffel M, Ahmad SO, Stanford JA, Levant B. A novel use of combined tyrosine hydroxylase and silver nucleolar staining to determine the effects of a unilateral intrastriatal 6-hydroxydopamine lesion in the substantia nigra: a stereological study. J Neurosci Methods 2012; 210:187-94. [PMID: 22850559 PMCID: PMC3443281 DOI: 10.1016/j.jneumeth.2012.07.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Revised: 07/20/2012] [Accepted: 07/23/2012] [Indexed: 11/22/2022]
Abstract
Neurotoxic lesions of the nigrostriatal pathway model the deficits found in Parkinson's disease. This study used stereology and a novel staining method to examine the effects of a partial unilateral striatal 6-hydroxydopamine (6-OHDA) lesion on substantia nigra pars compacta (SNpc) dopamine neuron number and morphology in rats. Adult male Long-Evans rats were subjected to unilateral lesion of the SNpc by intrastriatal microinjection of 6-OHDA (12.5 μg). Lesions were verified by d-amphetamine-stimulated rotation (2.5 mg/kg, sc) by force-plate rotometry 7 days post-surgery. Seven days after rotation testing, rats were euthanized, and brains were prepared for either histology (n=12) or determination of striatal dopamine content by HPLC-EC (n=20). Brains prepared for histology were stained for tyrosine hydroxylase (TH) combined with a silver nucleolar (AgNOR) stain using a modified protocol developed for stereological assessment. The AgNOR counterstain allowed for precise definition of the nucleolus of the cells, facilitating both counting and qualitative morphometry of TH-positive neurons. Stereological quantitation determined a 54% decrease in TH-positive neuron number (P<0.01), and a 14% decrease in neuron volume (P<0.05) on the lesioned side. Striatal dopamine concentration was decreased by 92% (P<0.01), suggesting that striatal dopamine analysis may overestimate the numbers of SNpc neurons lost. These findings demonstrate that combined use of TH and AgNOR staining provides improved characterization of 6-OHDA-induced pathology. Furthermore, the data suggest that decreased neuronal volume as well as number contributes to the functional deficits observed after unilateral intrastriatal 6-OHDA lesion.
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Affiliation(s)
- Michelle Healy-Stoffel
- Department of Pharmacology, Toxicology, and Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160 USA
| | - S. Omar Ahmad
- Department of Occupational Therapy, Doisy College of Health Sciences, St. Louis University, St. Louis, MO 63104 USA
| | - John A. Stanford
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS 66160 USA
| | - Beth Levant
- Department of Pharmacology, Toxicology, and Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160 USA
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Tarozzi A, Morroni F, Bolondi C, Sita G, Hrelia P, Djemil A, Cantelli-Forti G. Neuroprotective effects of erucin against 6-hydroxydopamine-induced oxidative damage in a dopaminergic-like neuroblastoma cell line. Int J Mol Sci 2012; 13:10899-10910. [PMID: 23109827 PMCID: PMC3472719 DOI: 10.3390/ijms130910899] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Revised: 08/20/2012] [Accepted: 08/22/2012] [Indexed: 11/16/2022] Open
Abstract
Oxidative stress (OS) contributes to the cascade leading to the dysfunction or death of dopaminergic neurons during Parkinson’s disease (PD). A strategy to prevent the OS of dopaminergic neurons may be the use of phytochemicals as inducers of endogenous antioxidants and phase 2 enzymes. In this study, we demonstrated that treatment of the dopaminergic-like neuroblastoma SH-SY5Y cell line with isothiocyanate erucin (ER), a compound of cruciferous vegetables, resulted in significant increases of both total glutathione (GSH) levels and total antioxidant capacity at the cytosolic level. The increase of GSH levels was associated with an increase in the resistance of SH-SY5Y cells to neuronal death, in terms of apoptosis, induced by 6-hydroxydopamine (6-OHDA). The pretreatment of SH-SY5Y cells with ER was also shown to prevent the redox status impairment, in terms of intracellular ROS and O2•− formation, and loss of mitochondrial membrane potential, early events that are initiators of the apoptotic process, induced by 6-OHDA. Last, the antiapoptotic and antioxidant effects of ER were abolished by buthionine sulfoximine, supporting the main role of GSH in the neuroprotective effects recorded by ER. These results suggest that ER may prevent the oxidative damage induced by 6-OHDA.
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Affiliation(s)
- Andrea Tarozzi
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +39-51-2091810; Fax: +39-51-248862
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272
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Malloy JN, Paulose JK, Li Y, Cassone VM. Circadian rhythms of gastrointestinal function are regulated by both central and peripheral oscillators. Am J Physiol Gastrointest Liver Physiol 2012; 303:G461-73. [PMID: 22723262 PMCID: PMC3423141 DOI: 10.1152/ajpgi.00369.2011] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Circadian clocks are responsible for daily rhythms in a wide array of processes, including gastrointestinal (GI) function. These are vital for normal digestive rhythms and overall health. Previous studies demonstrated circadian clocks within the cells of GI tissue. The present study examines the roles played by the suprachiasmatic nuclei (SCN), master circadian pacemaker for overt circadian rhythms, and the sympathetic nervous system in regulation of circadian GI rhythms in the mouse Mus musculus. Surgical ablation of the SCN abolishes circadian locomotor, feeding, and stool output rhythms when animals are presented with food ad libitum, while restricted feeding reestablishes these rhythms temporarily. In intact mice, chemical sympathectomy with 6-hydroxydopamine has no effect on feeding and locomotor rhythmicity in light-dark cycles or constant darkness but attenuates stool weight and stool number rhythms. Again, however, restricted feeding reestablishes rhythms in locomotor activity, feeding, and stool output rhythms. Ex vivo, intestinal tissue from PER2::LUC transgenic mice expresses circadian rhythms of luciferase bioluminescence. Chemical sympathectomy has little effect on these rhythms, but timed administration of the β-adrenergic agonist isoproterenol causes a phase-dependent shift in PERIOD2 expression rhythms. Collectively, the data suggest that the SCN are required to maintain feeding, locomotor, and stool output rhythms during ad libitum conditions, acting at least in part through daily activation of sympathetic activity. Even so, this input is not necessary for entrainment to timed feeding, which may be the province of oscillators within the intestines themselves or other components of the GI system.
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Affiliation(s)
- Jaclyn N. Malloy
- 1Department of Biology, University of Kentucky, Lexington, Kentucky; and
| | - Jiffin K. Paulose
- 2Center for Research on Biological Clocks, Texas A & M University, College Station, Texas
| | - Ye Li
- 1Department of Biology, University of Kentucky, Lexington, Kentucky; and
| | - Vincent M. Cassone
- 1Department of Biology, University of Kentucky, Lexington, Kentucky; and
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273
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Abstract
It is well-established that the sympathetic nervous system (SNS) regulates adipocyte metabolism and recently it has been reported that sensory afferents from white fat overlap anatomically with sympathetic efferents to white fat. The studies described here characterize the response of intact fat pads to selective sympathectomy (local 6-hydroxydopamine (6OHDA) injections) of inguinal (ING) or epididymal (EPI) fat in male NIH Swiss mice and provide in vivo evidence for communication between individual white and brown fat depots. The contralateral ING pad, both EPI pads, perirenal (PR), and mesenteric (MES) pads were significantly enlarged 4 weeks after denervating one ING pad, but only intrascapular brown adipose tissue (IBAT) increased when both ING pads were denervated. Denervation of one or both EPI pad had no effect on fat depot weights. In an additional experiment, norepinephrine turnover (NETO) was inhibited in ING, retroperitoneal (RP), MES, and IBAT 2 days after denervation of both EPI or of both ING pads. NE content was reduced to 10-30% of control values in all fat depots. There was no relation between early changes in NETO and fat pad weight 4 weeks after denervation, even though the reduction in NE content of intact fat pads was maintained. These data demonstrate that there is communication among individual fat pads, presumably through central integration of activity of sensory afferent and sympathetic efferent fibers, that changes sympathetic drive to white adipose tissue in a unified manner. In specific situations, removal of sympathetic efferents to one pad induces a compensatory enlargement of other intact depots.
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Affiliation(s)
- Ruth B S Harris
- Department of Physiology, Georgia Health Sciences University, Augusta, GA, USA.
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274
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Bossolasco P, Cova L, Levandis G, Diana V, Cerri S, Deliliers GL, Polli E, Silani V, Blandini F, Armentero MT. Noninvasive near-infrared live imaging of human adult mesenchymal stem cells transplanted in a rodent model of Parkinson's disease. Int J Nanomedicine 2012; 7:435-47. [PMID: 22334776 PMCID: PMC3273978 DOI: 10.2147/ijn.s27537] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND We have previously shown that human mesenchymal stem cells (hMSCs) can reduce toxin-induced neurodegeneration in a well characterized rodent model of Parkinson's disease. However, the precise mechanisms, optimal cell concentration required for neuroprotection, and detailed cell tracking need to be defined. We exploited a near-infrared imaging platform to perform noninvasive tracing following transplantation of tagged hMSCs in live parkinsonian rats. METHODS hMSCs were labeled both with a membrane intercalating dye, emitting in the near- infrared 815 nm spectrum, and the nuclear counterstain, Hoechst 33258. Effects of near-infrared dye on cell metabolism and proliferation were extensively evaluated in vitro. Tagged hMSCs were then administered to parkinsonian rats bearing a 6-hydroxydopamine-induced lesion of the nigrostriatal pathway, via two alternative routes, ie, intrastriatal or intranasal, and the cells were tracked in vivo and ex vivo using near-infrared technology. RESULTS In vitro, NIR815 staining was stable in long-term hMSC cultures and did not interfere with cell metabolism or proliferation. A significant near-infrared signal was detectable in vivo, confined around the injection site for up to 14 days after intrastriatal transplantation. Conversely, following intranasal delivery, a strong near-infrared signal was immediately visible, but rapidly faded and was completely lost within 1 hour. After sacrifice, imaging data were confirmed by presence/absence of the Hoechst signal ex vivo in coronal brain sections. Semiquantitative analysis and precise localization of transplanted hMSCs were further performed ex vivo using near-infrared imaging. CONCLUSION Near-infrared technology allowed longitudinal detection of fluorescent-tagged cells in living animals giving immediate information on how different delivery routes affect cell distribution in the brain. Near-infrared imaging represents a valuable tool to evaluate multiple outcomes of transplanted cells, including their survival, localization, and migration over time within the host brain. This procedure considerably reduces the number of animal experiments needed, as well as interindividual variability, and may favor the development of efficient therapeutic strategies promptly applicable to patients.
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Affiliation(s)
- P Bossolasco
- Fondazione Matarelli, Dipartimento di Farmacologia, Chemioterapia e Tossicologia Medica, Università degli Studi di Milano, Milan
| | - L Cova
- Department of Neurology and Laboratory of Neuroscience-IRCCS Istituto Auxologico Italiano, Cusano Milanino
| | - G Levandis
- Laboratory of Functional Neurochemistry, Interdepartmental Research Centre for Parkinson’s Disease, IRCCS National Institute of Neurology “C Mondino”, Pavia
| | - V Diana
- Department of Neurology and Laboratory of Neuroscience-IRCCS Istituto Auxologico Italiano, Cusano Milanino
| | - S Cerri
- Laboratory of Functional Neurochemistry, Interdepartmental Research Centre for Parkinson’s Disease, IRCCS National Institute of Neurology “C Mondino”, Pavia
| | - G Lambertenghi Deliliers
- Fondazione Matarelli, Dipartimento di Farmacologia, Chemioterapia e Tossicologia Medica, Università degli Studi di Milano, Milan
| | - E Polli
- Fondazione Matarelli, Dipartimento di Farmacologia, Chemioterapia e Tossicologia Medica, Università degli Studi di Milano, Milan
| | - V Silani
- Department of Neurology and Laboratory of Neuroscience-IRCCS Istituto Auxologico Italiano, Cusano Milanino
- Department of Neurology and Laboratory of Neuroscience, Centro “Dino Ferrari” Università degli Studi di Milano-IRCCS Istituto Auxologico Italiano, Milan, Italy
| | - F Blandini
- Laboratory of Functional Neurochemistry, Interdepartmental Research Centre for Parkinson’s Disease, IRCCS National Institute of Neurology “C Mondino”, Pavia
| | - MT Armentero
- Laboratory of Functional Neurochemistry, Interdepartmental Research Centre for Parkinson’s Disease, IRCCS National Institute of Neurology “C Mondino”, Pavia
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Abstract
Parkinson's disease (PD) is the most common neurodegenerative disease of the basal ganglia. Like other adult-onset neurodegenerative disorders, it is without a treatment that forestalls its chronic progression. Efforts to develop disease-modifying therapies to date have largely focused on the prevention of degeneration of the neuron soma, with the tacit assumption that such approaches will forestall axon degeneration as well. We herein propose that future efforts to develop neuroprotection for PD may benefit from a shift in focus to the distinct mechanisms that underlie axon degeneration. We review evidence from human post-mortem studies, functional neuroimaging, genetic causes of the disease and neurotoxin models that axon degeneration may be the earliest feature of the disease, and it may therefore be the most appropriate target for early intervention. In addition, we present evidence that the molecular mechanisms of degeneration of axons are separate and distinct from those of neuron soma. Progress is being made in understanding these mechanisms, and they provide possible new targets for therapeutic intervention. We also suggest that the potential for axon re-growth in the adult central nervous system has perhaps been underestimated, and it offers new avenues for neurorestoration. In conclusion, we propose that a new focus on the neurobiology of axons, their molecular pathways of degeneration and growth, will offer novel opportunities for neuroprotection and restoration in the treatment of PD and other neurodegenerative diseases.
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Sarkaki A, Eidypour Z, Motamedi F, Keramati K, Farbood Y. Motor disturbances and thalamic electrical power of frequency bands' improve by grape seed extract in animal model of Parkinson's disease. Avicenna J Phytomed 2012; 2:222-32. [PMID: 25050252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2012] [Accepted: 08/13/2012] [Indexed: 11/28/2022]
Abstract
OBJECTIVE Previous studies showed that grape seed extract (GSE) is an excellent natural substance with potent antioxidant effect and free radical scavenger. This study aimed to evaluate the effect of GSE on motor dysfunctions and thalamic local Electroencephalography (EEG) frequency bands' powers in rats with Parkinson's disease (PD). MATERIALS AND METHODS In this study 8 µg 6-hydroxydopamine (6-OHDA) dissolved in 2 µl normal saline containing 0.01% ascorbic acid was infused into right medial forebrain bundle (MFB) to make an animal model of PD. Rats with PD received four weeks GSE (100 mg/kg, p.o.) after apomorphine-induced rotation test. Spontaneous motor tests and also thalamic ventroanterior nucleus (AV) local EEG recording were done in freely moving rats in all groups. RESULTS Chronic treatment of PD rats with GSE could influence potentially frequency bands' powers of thalamic VA and improve post-lesion motor dysfunctions significantly (p<0.05 and p<0.01, respectively). CONCLUSION Our findings suggest that GSE modulates the CNS function and has beneficial effects on the direct and indirect striato-thalamo-cortical pathways in PD. GSE acts as a new and potent natural free radical scavenger which removes oxidants produced by neurotoxin 6-OHDA in brain. Therefore, it reinforces electrical power of remained thalamic VA neurons and thereby improves post-lesion motor disorders.
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Choudhury ME, Sugimoto K, Kubo M, Nagai M, Nomoto M, Takahashi H, Yano H, Tanaka J. A cytokine mixture of GM-CSF and IL-3 that induces a neuroprotective phenotype of microglia leading to amelioration of (6-OHDA)-induced Parkinsonism of rats. Brain Behav 2011; 1:26-43. [PMID: 22398979 PMCID: PMC3217672 DOI: 10.1002/brb3.11] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Revised: 06/02/2011] [Accepted: 06/16/2011] [Indexed: 01/09/2023] Open
Abstract
Dopamine (DA) agonists are widely used as primary treatments for Parkinson's disease. However, they do not prevent progressive degeneration of dopaminergic neurons, the central pathology of the disease. In this study, we found that subcutaneous injection of a cytokine mixture containing granulocyte macrophage colony-stimulating factor and interleukin-3 (IL-3) markedly suppressed dopaminergic neurodegeneration in 6-hydroxydopamine-lesioned rats, an animal model of Parkinson's disease. The cytokine mixture suppressed the decrease of DA content in the striatum, and ameliorated motor function in the lesioned rats. In response to the cytokine injection, dopaminergic neurons in the substantia nigra pars compacta increased expression of the antiapoptotic protein Bcl-xL. Microglial activation in the pars compacta was evident in both the saline- and cytokine-injected rats. However, the cytokine mixture suppressed expression of the proinflammatory cytokines IL-1β and tumor necrosis factors α, and upregulated the neuroprotective factors insulin-like growth factor-1 and hepatocyte growth factor. Similar responses were observed in cultured microglia. Detailed morphometric analyses revealed that NG2 proteoglycan-expressing glial cells increased in the cytokine-injected rats, while astrocytic activation with increased expression of antioxidative factors was evident only in the saline-injected rats. Thus, the present findings show that the cytokine mixture was markedly effective in suppressing neurodegeneration. Its neuroprotective effects may be mediated by increased expression of Bcl-xL in dopaminergic neurons, and the activation of beneficial actions of microglia that promote neuronal survival. Furthermore, this cytokine mixture may have indirect actions on NG2 proteoglycan-expressing glia, whose role may be implicated in neuronal survival.
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Affiliation(s)
| | - Kana Sugimoto
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Toon, Ehime, Japan
- Department of Basic and Clinical Neuroscience, Ehime Proteo‐Medicine Research Center, Ehime University, Toon, Ehime, Japan
| | - Madoka Kubo
- Department of Therapeutic Medicine, Graduate School of Medicine, Ehime University, Toon, Ehime, Japan
| | - Masahiro Nagai
- Department of Therapeutic Medicine, Graduate School of Medicine, Ehime University, Toon, Ehime, Japan
| | - Masahiro Nomoto
- Department of Therapeutic Medicine, Graduate School of Medicine, Ehime University, Toon, Ehime, Japan
| | - Hisaaki Takahashi
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Toon, Ehime, Japan
- Department of Basic and Clinical Neuroscience, Ehime Proteo‐Medicine Research Center, Ehime University, Toon, Ehime, Japan
| | - Hajime Yano
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Toon, Ehime, Japan
- Department of Basic and Clinical Neuroscience, Ehime Proteo‐Medicine Research Center, Ehime University, Toon, Ehime, Japan
| | - Junya Tanaka
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Toon, Ehime, Japan
- Department of Basic and Clinical Neuroscience, Ehime Proteo‐Medicine Research Center, Ehime University, Toon, Ehime, Japan
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Morera-Herreras T, Ruiz-Ortega JÁ, Linazasoro G, Ugedo L. Nigrostriatal denervation changes the effect of cannabinoids on subthalamic neuronal activity in rats. Psychopharmacology (Berl) 2011; 214:379-89. [PMID: 20959968 PMCID: PMC3045509 DOI: 10.1007/s00213-010-2043-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2010] [Accepted: 09/30/2010] [Indexed: 02/03/2023]
Abstract
RATIONALE It is known that dopaminergic cell loss leads to increased endogenous cannabinoid levels and CB1 receptor density. OBJECTIVE The aim of this study was to evaluate the influence of dopaminergic cell loss, induced by injection of 6-hydroxydopamine, on the effects exerted by cannabinoid agonists on neuron activity in the subthalamic nucleus (STN) of anesthetized rats. RESULTS We have previously shown that Δ(9)-tetrahydrocannabinol (Δ(9)-THC) and anandamide induce both stimulation and inhibition of STN neuron activity and that endocannabinoids mediate tonic control of STN activity. Here, we show that in intact rats, the cannabinoid agonist WIN 55,212-2 stimulated all recorded STN neurons. Conversely, after dopaminergic depletion, WIN 55,212-2, Δ(9)-THC, or anandamide inhibited the STN firing rate without altering its discharge pattern, and stimulatory effects were not observed. Moreover, anandamide exerted a more intense inhibitory effect in lesioned rats in comparison to control rats. CONCLUSIONS Cannabinoids induce different effects on the STN depending on the integrity of the nigrostriatal pathway. These findings advance our understanding of the role of cannabinoids in diseases involving dopamine deficits.
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Affiliation(s)
- Teresa Morera-Herreras
- Department of Pharmacology, Faculty of Medicine, University of the Basque Country, 48940 Leioa, Vizcaya Spain
| | - José Ángel Ruiz-Ortega
- Department of Pharmacology, Faculty of Medicine, University of the Basque Country, 48940 Leioa, Vizcaya Spain
| | - Gurutz Linazasoro
- Centro Investigación Parkinson, Policlínica Gipuzkoa, San Sebastián, Gipuzkoa Spain
| | - Luisa Ugedo
- Department of Pharmacology, Faculty of Medicine, University of the Basque Country, 48940 Leioa, Vizcaya Spain
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279
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Zhang X, Egeland M, Svenningsson P. Antidepressant-like properties of sarizotan in experimental Parkinsonism. Psychopharmacology (Berl) 2011; 218:621-34. [PMID: 21647579 DOI: 10.1007/s00213-011-2356-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2010] [Accepted: 05/09/2011] [Indexed: 01/15/2023]
Abstract
RATIONALE Depression and anxiety are common symptoms in Parkinson's disease for which there are no optimal treatments. Sarizotan, an agonist at serotonin receptors and partial agonist at dopamine D₂-like receptors, has shown antidyskinetic effects in Parkinson's disease. Based on its pharmacological profile, we hypothesized that sarizotan could also have antidepressant-like properties. OBJECTIVES Examine effects of sarizotan on behavioral and histological measures known to be regulated by established antidepressants in normal and unilaterally 6-hydroxydopamine-lesioned rats. RESULTS Sarizotan was found to significantly reduce immobility in the modified forced swim test, a measure of antidepressant-like activity, but had no effects on thigmotaxis or corner time, measures of anxiety-like behavior, in the unilaterally 6-hydroxydopamine-lesioned rats. At the same dose, sarizotan counteracted L: -DOPA/benserazide-induced supersentitized rotational behavior and dyskinesias without significantly affecting L: -DOPA/benserazide-induced locomotion. At the histological level, sarizotan alone or in combination with L: -DOPA/benserazide stimulated cell proliferation, measured by bromodeoxyuridine incorporation or Ki-67 staining, both in the subgranular zone of the dentate gyrus and in the subventricular zone of the striatum in the 6-hydroxydopamine-lesioned hemisphere. Likewise, combined sarizotan and L: -DOPA/benserazide treatment stimulated doublecortin levels in the subgranular zone of the dentate gyrus. CONCLUSIONS These significant effects of sarizotan in the modified forced swim test and on cell proliferation are reminiscent of those found after various antidepressant therapies. These data suggest that sarizotan may have some antidepressant-like and restorative properties in Parkinsonism.
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280
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Ruan Q, Harrington AJ, Caldwell KA, Caldwell GA, Standaert DG. VPS41, a protein involved in lysosomal trafficking, is protective in Caenorhabditis elegans and mammalian cellular models of Parkinson's disease. Neurobiol Dis 2010; 37:330-8. [PMID: 19850127 PMCID: PMC2818321 DOI: 10.1016/j.nbd.2009.10.011] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2009] [Revised: 10/09/2009] [Accepted: 10/10/2009] [Indexed: 12/25/2022] Open
Abstract
VPS41 is a protein identified as a potential therapeutic target for Parkinson's disease (PD) as a result of a high-throughput RNAi screen in Caenorhabditis elegans. VPS41 has a plausible mechanistic link to the pathogenesis of PD, as in yeast it is known to participate in trafficking of proteins to the lysosomal system and several recent lines of evidence have pointed to the importance of lysosomal system dysfunction in the neurotoxicity of alpha-synuclein (alpha-syn). We found that expression of the human form of VPS41 (hVPS41) prevents dopamine (DA) neuron loss induced by alpha-syn overexpression and 6-hydroxydopamine (6-OHDA) neurotoxicity in C. elegans. In SH-SY5Y neuroblastoma cell lines stably transfected with hVPS41, we determined that presence of this protein conferred protection against the neurotoxins 6-OHDA and rotenone. Overexpression of hVPS41 did not alter the mitochondrial membrane depolarization induced by these neurotoxins. hVPS41 did, however, block downstream events in the apoptotic cascade including activation of caspase-9 and caspase-3, and PARP cleavage. We also observed that hVPS41 reduced the accumulation of insoluble high-molecular weight forms of alpha-syn in SH-SY5Y cells after treatment with rotenone. These data show that hVPS41 is protective against both alpha-syn and neurotoxic-mediated injury in invertebrate and cellular models of PD. These protective functions may be related to enhanced clearance of misfolded or aggregated protein, including alpha-syn. Our studies indicate that hVPS41 may be a useful target for developing therapeutic strategies for human PD.
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Affiliation(s)
- Qingmin Ruan
- Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, Alabama
| | - Adam J. Harrington
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, Alabama
| | - Kim A. Caldwell
- Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, Alabama
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, Alabama
| | - Guy A. Caldwell
- Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, Alabama
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, Alabama
| | - David G. Standaert
- Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, Alabama
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Walton ME, Groves J, Jennings KA, Croxson PL, Sharp T, Rushworth MFS, Bannerman DM. Comparing the role of the anterior cingulate cortex and 6-hydroxydopamine nucleus accumbens lesions on operant effort-based decision making. Eur J Neurosci 2009; 29:1678-91. [PMID: 19385990 PMCID: PMC2954046 DOI: 10.1111/j.1460-9568.2009.06726.x] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Both the anterior cingulate cortex (ACC) and mesolimbic dopamine, particularly in the nucleus accumbens (NAc), have been implicated in allowing an animal to overcome effort constraints to obtain greater benefits. However, their exact contribution to such decisions has, to date, never been directly compared. To investigate this issue we tested rats on an operant effort-related cost-benefit decision-making task where animals selected between two response alternatives, one of which involved investing effort by lever pressing on a high fixed-ratio (FR) schedule to gain high reward [four food pellets (HR)], whereas the other led to a small amount of food on an FR schedule entailing less energetic cost [two food pellets, low reward (LR)]. All animals initially preferred to put in work to gain the HR. Systemic administration of a D2 antagonist caused a significant switch in choices towards the LR option. Similarly, post-operatively, excitotoxic ACC lesions caused a significant bias away from HR choices compared with sham-lesioned animals. There was no slowing in the speed of lever pressing and no correlation between time to complete the FR requirement and choice performance. Unexpectedly, no such alteration in choice allocation was observed in animals following 6-hydroxydopamine NAc lesions. However, these rats were consistently slower to initiate responding when cued to commence each trial and also showed a reduction in food hoarding on a species-typical foraging task. Taken together, this implies that only ACC lesions, and not 6-hydroxydopamine NAc lesions as performed here, cause a bias away from investing effort for greater reward when choosing between competing options
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Affiliation(s)
- Mark E Walton
- Department of Experimental Psychology, University of Oxford, South Parks Road, Oxford OX1 3UD, UK.
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Riveles K, Huang LZ, Quik M. Cigarette smoke, nicotine and cotinine protect against 6-hydroxydopamine-induced toxicity in SH-SY5Y cells. Neurotoxicology 2008; 29:421-7. [PMID: 18359086 PMCID: PMC2486261 DOI: 10.1016/j.neuro.2008.02.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2007] [Revised: 01/23/2008] [Accepted: 02/05/2008] [Indexed: 11/22/2022]
Abstract
Epidemiological studies consistently demonstrate a reduced incidence of Parkinson's disease in smokers. As an approach to evaluate whether nicotine in tobacco may be involved in this apparent protective effect, we compared the effect of mainstream 1R4F cigarette smoke solutions, which contain chemicals inhaled by active smokers, and nicotine against 6-hydroxydopamine (6-OHDA)-induced toxicity in an in vitro cell culture system. For this purpose we used terminally differentiated SH-SY5Y neuroblastoma cells that exhibit a catecholaminergic phenotype and express nicotinic receptors. Cells were pre-incubated for 24 h in mainstream-cigarette smoke solutions (0.06, 0.2, or 0.6 cigarette puffs/ml) made from University of Kentucky 1R4F research brand cigarettes, followed by the addition of 6-OHDA for another 24-48 h. The 0.2, but not 0.06, puffs/ml dose, significantly protected against 6-OHDA-induced toxicity in SH-SY5Y cells. This dose yielded final nicotine concentrations of approximately 5 x 10(-7) M, which is similar to plasma smoking levels. Although the 0.6 puffs/ml dose caused significant toxicity on its own, it also appeared to protect against 6-OHDA-induced damage. We next tested the effect of nicotine, as well as its metabolite cotinine. These agents protected against the toxic effects of 6-OHDA in SH-SY5Y cells at concentrations ranging from 10(-7) to 10(-5) M. These combined results support the idea that nicotine is one of the components in cigarette smoke that has a protective effect against neurotoxic insults. These data suggest that nicotine may be of potential therapeutic value for Parkinson's disease.
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Affiliation(s)
| | | | - Maryka Quik
- The Parkinson’s Institute, Sunnyvale, CA 94085
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283
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Park YS, Jeon MF, Lee BH, Chang JW. Lesion of subthalamic nucleus in parkinsonian rats : effects of dopamine d(1) and d(2) receptor agonists on the neuronal activities of the substantia nigra pars reticulata. J Korean Neurosurg Soc 2007; 42:455-61. [PMID: 19096589 DOI: 10.3340/jkns.2007.42.6.455] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2007] [Accepted: 08/10/2007] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE It was hypothesized that dopamine agonist administration and subthalamic nucleus (STN) lesion in the rat might have a synergistic effect on the neuronal activities of substantia nigra pars reticulata (SNpr) as observed in patients with Parkinson's disease. The effects of SKF38393 (a D(1) receptor agonist) and Quinpirole (a D(2) receptor agonist) were compared in parkinsonian rat models with 6- hydroxydopamine (6-OHDA) after STN lesion. METHODS SKF38393 and Quinpirole were consecutively injected intrastriatally. SNpr was microrecorded to ascertain the activity of the basal ganglia output structure. The effect of SKF38393 or Quinpirole injection on the firing rate and firing patterns of SNpr was investigated in medial forebrain bundle (MFB) lesioned rats and in MFB+STN lesioned rats. RESULTS The administration of SKF38393 decreased SNpr neuronal firing rates and the percentage of burst neurons in the MFB lesioned rats, but did not alter them in MFB+STN lesioned rats. The administration ofQuinpirole significantly decreased the spontaneous firing rate in the MFB lesioned rats. However, after an additional STN lesion, it increased the percentage of burst neurons. CONCLUSION This study demonstrated that dopamine agonists and STN lesion decreased the hyperactive firing rate and the percentage of burst neurons of SNpr neurons in 6-OHDA lesioned rats, respectively. Quinpirole with STN lesion increased a percentage of burst neurons. To clear the exact interactive mechanism of D(1) and D(2) agonist and the corresponding location, it should be followed a study using a nonselective dopamine agonist and D(1), D(2) selective antagonist.
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Affiliation(s)
- Yong Sook Park
- Department of Neurosurgery , Chung-Ang University, College of Medicine, Seoul, Korea
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284
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Abstract
Reactive oxygen species (ROS) are implicated in 6-hydroxydopamine (6-OHDA) injury to catecholaminergic neurons; however, the mechanism(s) are unclear. In addition to ROS generated during autoxidation, 6-OHDA may initiate secondary cellular sources of ROS that contribute to toxicity. Using a neuronal cell line, we found that catalytic metalloporphyrin antioxidants conferred protection if added 1 h after exposure to 6-OHDA, whereas the hydrogen peroxide scavenger catalase failed to protect if added more than 15 min after 6-OHDA. There was a temporal correspondence between loss of protection and loss of the ability of the antioxidant to inhibit 6-OHDA-induced ERK phosphorylation. Time course studies of aconitase inactivation, an indicator of intracellular superoxide, and MitoSOX red, a mitochondria targeted ROS indicator, demonstrate early intracellular ROS followed by a delayed phase of mitochondrial ROS production, associated with phosphorylation of a mitochondrial pool of ERK. Furthermore, on initiation of mitochondrial ROS and ERK activation, 6-OHDA-injured cells became refractory to rescue by metalloporphyrin antioxidants. Together with previous studies showing that inhibition of the ERK pathway confers protection from 6-OHDA toxicity, and that phosphorylated ERK accumulates in mitochondria of degenerating human Parkinson's disease neurons, these studies implicate mitochondrial ERK activation in Parkinsonian oxidative neuronal injury.
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Affiliation(s)
- Scott M Kulich
- Department of Pathology, VA Pittsburgh Healthcare System, Pittsburgh, PA 15240, USA.
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285
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Lopez S, Turle-Lorenzo N, Acher F, De Leonibus E, Mele A, Amalric M. Targeting group III metabotropic glutamate receptors produces complex behavioral effects in rodent models of Parkinson's disease. J Neurosci 2007; 27:6701-11. [PMID: 17581957 PMCID: PMC6672706 DOI: 10.1523/jneurosci.0299-07.2007] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2006] [Revised: 05/11/2007] [Accepted: 05/11/2007] [Indexed: 12/12/2022] Open
Abstract
Drugs activating group III metabotropic glutamate receptors (mGluRs) represent therapeutic alternatives to L-DOPA (L-3,4-dihydroxyphenylalanine) for the treatment of Parkinson's disease (PD). Their presynaptic location at GABAergic and glutamatergic synapses within basal ganglia nuclei provide a critical target to reduce abnormal activities associated with PD. The effects of selective group III mGluR agonists (1S,3R,4S)-1-aminocyclopentane-1,3,4-tricarboxylic acid (ACPT-I) and L-(+)-2-amino-4-phosphonobutyric acid (L-AP4) infused into the globus pallidus (GP) or the substantia nigra pars reticulata (SNr) were thus studied in rat models of PD. Bilateral infusions of ACPT-I (1, 2.5, and 5 nmol/microl) into the GP fully reverse the severe akinetic deficits produced by 6-hydroxydopamine nigrostriatal dopamine lesions in a reaction-time task without affecting the performance of controls. Similar results were observed after L-AP4 (1 nmol) or picrotoxin, a GABA(A) receptor antagonist, infused into the GP. In addition, intrapallidal ACPT-I counteracts haloperidol-induced catalepsy. This effect is reversed by concomitant administration of a selective group III receptor antagonist (RS)-alpha-cyclopropyl-4-phosphonophenylglycine. In contrast, ACPT-I (0.05, 0.1, and 0.25 nmol) infusions into the SNr enhance the lesion-induced akinetic deficits in control and lesioned rats and do not reverse haloperidol-induced catalepsy. L-AP4 (0.05 nmol) and picrotoxin in the SNr produce the same effects. Together, these results show that activation of group III mGluRs in the GP provides benefits in parkinsonian rats, presumably by modulating GABAergic neurotransmission. The opposite effects produced by group III mGluR activation in the SNr, also observed with a selective mGluR8 agonist, support the use of subtype-selective group III mGluR agonists as a potential antiparkinsonian strategy.
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Affiliation(s)
- Sebastien Lopez
- Laboratoire de Neurobiologie de la Cognition, Aix-Marseille Université, Centre National de la Recherche Scientifique (CNRS) Unité Mixte de Recherche (UMR) 6155, 13331 Marseille, France
| | - Nathalie Turle-Lorenzo
- Laboratoire de Neurobiologie de la Cognition, Aix-Marseille Université, Centre National de la Recherche Scientifique (CNRS) Unité Mixte de Recherche (UMR) 6155, 13331 Marseille, France
| | - Francine Acher
- Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, UMR 8601-CNRS, Université René Descartes-Paris V, 75270 Paris Cedex 06, France, and
| | - Elvira De Leonibus
- Dipartimento di Genetica e Biologia Molecolare C. Darwin, Università degli Studi di Roma La Sapienza, 00185 Rome, Italy
| | - Andrea Mele
- Dipartimento di Genetica e Biologia Molecolare C. Darwin, Università degli Studi di Roma La Sapienza, 00185 Rome, Italy
| | - Marianne Amalric
- Laboratoire de Neurobiologie de la Cognition, Aix-Marseille Université, Centre National de la Recherche Scientifique (CNRS) Unité Mixte de Recherche (UMR) 6155, 13331 Marseille, France
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Raffel DM, Chen W, Sherman PS, Gildersleeve DL, Jung YW. Dependence of cardiac 11C-meta-hydroxyephedrine retention on norepinephrine transporter density. J Nucl Med 2006; 47:1490-6. [PMID: 16954558 PMCID: PMC1618973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023] Open
Abstract
UNLABELLED The norepinephrine analog (11)C-meta-hydroxyephedrine (HED) is used with PET to map the regional distribution of cardiac sympathetic neurons. HED is rapidly transported into sympathetic neurons by the norepinephrine transporter (NET) and stored in vesicles. Although much is known about the neuronal mechanisms of HED uptake and retention, there is little information about the functional relationship between HED retention and cardiac sympathetic nerve density. The goal of this study was to characterize the dependence of HED retention on nerve density in rats with graded levels of cardiac denervation induced chemically with the neurotoxin 6-hydroxydopamine (6-OHDA). METHODS Thirty male Sprague-Dawley rats were divided into 6 groups, and each group was administered a different dose of 6-OHDA: 0 (controls), 7, 11, 15, 22, and 100 mg/kg intraperitoneally. One day after 6-OHDA injection, HED (3.7-8.3 MBq) was injected intravenously into each animal and HED concentrations in heart and blood at 30 min after injection were determined. Heart tissues were frozen and later processed by tissue homogenization and differential centrifugation into a membrane preparation for in vitro measurement of cardiac NET density. A saturation binding assay using (3)H-mazindol as the radioligand was used to measure NET density (maximum number of binding sites [B(max)], fmol/mg protein) for each heart. RESULTS In control animals, NET B(max) was 388 +/- 23 fmol/mg protein and HED heart uptake (HU) at 30 min was 2.89% +/- 0.35 %ID/g (%ID/g is percentage injected dose per gram tissue). The highest 6-OHDA dose of 100 mg/kg caused severe cardiac denervation, decreasing both NET B(max) and HED HU to 8% of their control values. Comparing values for all doses of 6-OHDA, HED retention had a strong linear correlation with NET density: HU = 0.0077B(max) -0.028, r(2) = 0.95. CONCLUSION HED retention is linearly dependent on NET density in rat hearts that have been chemically denervated with 6-OHDA, suggesting that HED retention is a good surrogate measure of NET density in the rat heart. This finding is discussed in relation to clinical observations of the dependence of HED retention on cardiac nerve density in human subjects using PET.
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Affiliation(s)
- David M Raffel
- Department of Radiology, Division of Nuclear Medicine, University of Michigan Medical School, Ann Arbor, 48109-0552, USA.
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287
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Corvol JC, Muriel MP, Valjent E, Féger J, Hanoun N, Girault JA, Hirsch EC, Hervé D. Persistent increase in olfactory type G-protein alpha subunit levels may underlie D1 receptor functional hypersensitivity in Parkinson disease. J Neurosci 2004; 24:7007-14. [PMID: 15295036 PMCID: PMC6729591 DOI: 10.1523/jneurosci.0676-04.2004] [Citation(s) in RCA: 132] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2004] [Revised: 06/13/2004] [Accepted: 06/13/2004] [Indexed: 11/21/2022] Open
Abstract
Although L-dopa remains the most effective treatment of Parkinson disease, its long-term administration is hampered by the appearance of dyskinesia. Hypersensitivity of dopamine D1 receptors in the striatum has been suggested to contribute to the genesis of these delayed adverse effects. However, D1 receptor amounts are unchanged in Parkinson disease, suggesting alterations of downstream effectors. In rodents, striatal D1 receptors activate adenylyl cyclase through olfactory type G-protein alpha subunit (Galphaolf) and G-protein gamma 7 subunit (Ggamma7). We found that Galphaolf was enriched in human basal ganglia and was markedly diminished in the putamen of patients with Huntington disease, in relation with the degeneration of medium spiny neurons. In contrast, in the putamen of patients with Parkinson disease, Galphaolf and Ggamma7 levels were both significantly increased. In the rat, the degeneration of dopamine neurons augmented Galphaolf levels in the striatal neurons, specifically at the plasma membrane, an effect accounting for the increase of D1 response on cAMP production in dopamine-depleted striatum. In lesioned rats, Galphaolf levels were normalized by a 3 week treatment with l-dopa or a D1 agonist but not with aD2-D3 agonist, supporting a Galphaolf regulation by D1 receptor usage. In contrast, the increases of Galphaolf levels in patients were not affected by the duration of l-dopa treatment but correlated with duration of disease. In conclusion, our results revealed in the parkinsonian putamen a prolonged elevation of Galphaolf levels that may lead to a persistent D1 receptor hypersensitivity and contribute to the genesis of long-term complications of L-dopa.
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Affiliation(s)
- Jean-Christophe Corvol
- Institut National de la Santé et de la Recherche Médicale-Université Pierre et Marie Curie Unité 536, Institut du Fer à Moulin, 75005 Paris, France.
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288
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Yoshimura N, Kuno S, Chancellor MB, De Groat WC, Seki S. Dopaminergic mechanisms underlying bladder hyperactivity in rats with a unilateral 6-hydroxydopamine (6-OHDA) lesion of the nigrostriatal pathway. Br J Pharmacol 2003; 139:1425-32. [PMID: 12922929 PMCID: PMC1573982 DOI: 10.1038/sj.bjp.0705388] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1. This study was undertaken to elucidate dopaminergic mechanisms underlying bladder hyperactivity in a rat model of Parkinson's disease (PD) induced by a unilateral 6-OHDA injection into the substantia nigra pars compacta. 2. In 6-OHDA-lesioned rats, voided volume per micturition (0.41+/-0.04 ml, mean+/-s.e.m.) measured during 24 h in a metabolic cage was significantly smaller than in sham-operated rats (0.67+/-0.07 ml). 3. Cystrometrograms (CMG) in conscious animals revealed significantly smaller bladder capacity (BC) (0.46+/-0.03 ml) in 6-OHDA-lesioned rats than in sham rats (0.72+/-0.06 ml). 4. SKF38393 (D1/D5 receptor agonist, i.v.) significantly increased BC in 6-OHDA rats without apparent effects in sham rats. SKF38393 applied intracerebroventricularly (i.c.v.) under urethane anesthesia also increased BC in 6-OHDA-lesioned rats and by a smaller increment in sham rats. 5. In contrast, quinpirole (D2/D3/D4 receptor agonist, i.v.) significantly reduced BC in sham and 6-OHDA-lesioned rats. Intrathecal injection of quinpirole similarly reduced BC in sham and 6-OHDA-lesioned rats. 6. PD128907 (D(3)-receptor agonist) did not have significant effects on BC in 6-OHDA-lesioned rats. 7. These results indicate that a rat model of PD exhibited bladder hyperactivity as observed in patients with PD, and that stimulation of D1/D5 dopamine receptors at a supraspinal site can suppress bladder hyperactivity in PD, whereas stimulation of D2/D4, but not D3, dopamine receptors had the opposite effect to reduce bladder capacity. Thus, D1/D5 dopamine receptor agonists might be effective in treating neurogenic bladder hyperactivity in PD.
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MESH Headings
- 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine/administration & dosage
- 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine/pharmacology
- Animals
- Benzopyrans/administration & dosage
- Benzopyrans/pharmacology
- Disease Models, Animal
- Dopamine Agonists/administration & dosage
- Dopamine Agonists/pharmacology
- Dose-Response Relationship, Drug
- Injections, Intravenous
- Injections, Intraventricular
- Male
- Microinjections
- Oxazines/administration & dosage
- Oxazines/pharmacology
- Oxidopamine/toxicity
- Parkinson Disease/metabolism
- Parkinson Disease/physiopathology
- Quinpirole/administration & dosage
- Quinpirole/pharmacology
- Rats
- Rats, Sprague-Dawley
- Receptors, Dopamine/metabolism
- Substantia Nigra/drug effects
- Urinary Bladder/physiopathology
- Urination/drug effects
- Urination/physiology
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Affiliation(s)
- Naoki Yoshimura
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, U.S.A.
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289
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Sellings LHL, Clarke PBS. Segregation of amphetamine reward and locomotor stimulation between nucleus accumbens medial shell and core. J Neurosci 2003; 23:6295-303. [PMID: 12867514 PMCID: PMC6740552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2003] [Revised: 04/23/2003] [Accepted: 05/15/2003] [Indexed: 03/03/2023] Open
Abstract
Convergent evidence suggests that amphetamine (AMPH) exerts its rewarding and locomotor stimulating effects via release of dopamine in the nucleus accumbens. However, there is no consensus as to the relative contributions of core and medial shell subregions to these effects. Moreover, the literature is based primarily on intracranial administration, which cannot fully mimic the drug distribution achieved by systemic administration. In the present study, the effects of bilateral 6-hydroxydopamine lesions of the accumbens core or medial shell on rewarding and locomotor stimulating effects of systemically administered amphetamine (0.75 mg/kg, i.p.) were examined in a conditioned place preference (CPP) procedure relying solely on tactile cues (floor texture). Residual dopamine innervation was quantified by [125I]-RTI-55 binding to the dopamine transporter. When lesions were performed before the conditioning phase, AMPH-induced locomotor stimulation and CPP magnitude were positively correlated with residual dopamine transporter binding in core and medial shell, respectively. Medial shell lesions did not affect morphine CPP, arguing that a sensory or mnemonic deficit was not responsible for the lesion-induced reduction in AMPH CPP. Medial shell lesions performed between the conditioning phase and the test day reduced the expression of amphetamine CPP. These results suggest that after systemic amphetamine administration, rewarding and locomotor stimulating effects of the drug are anatomically dissociated within the nucleus accumbens: the medial shell contributes to rewarding effects, whereas the core contributes to behavioral activation.
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Affiliation(s)
- Laurie H L Sellings
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Quebec, Canada H3G 1Y6
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290
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Han BS, Hong HS, Choi WS, Markelonis GJ, Oh TH, Oh YJ. Caspase-dependent and -independent cell death pathways in primary cultures of mesencephalic dopaminergic neurons after neurotoxin treatment. J Neurosci 2003; 23:5069-78. [PMID: 12832530 PMCID: PMC6741197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023] Open
Abstract
Although the cause of neuronal death in Parkinson's disease (PD) is mainly unknown, growing evidence suggests that both apoptotic and non-apoptotic death may occur in PD. Using primary cultures of mesencephalic dopaminergic neurons and the MN9D dopaminergic neuronal cell line, we attempted to evaluate specifically the existence of the mitochondrial apoptotic pathway, focusing on the mitochondrial release of cytochrome c to the activation of the caspases after 6-hydroxydopamine (6-OHDA) or 1-methyl-4-phenylpyridinium (MPP+) treatment. Both immunofluorescent labeling and immunoblot analysis indicated mitochondrial release of cytochrome c into the cytosol after 6-OHDA or MPP+ treatment. However, the appearance of activated caspase-3 immunoreactivity in tyrosine hydroxylase (TH)-positive neurons was detected only after 6-OHDA. Immunoblot and biochemical analysis also confirmed that activation of both caspase-9 and caspase-3 was induced by 6-OHDA, but not by MPP+. Consequently, cotreatment with a caspase inhibitor (zVAD-fmk) or with an antioxidant (N-acetylcysteine) not only deterred 6-OHDA-induced loss of TH-positive neurons but also abolished the appearance of activated caspase-3 in TH-positive neurons. In contrast, the same treatment did not spare MPP+-treated TH-positive neurons. Interestingly, a reconstitution assay indicated that the addition of ATP to the cytosolic fraction obtained from MPP+-treated cells was sufficient to activate both caspase-9 and caspase-3. Taken together, our results indicate that distinct mechanisms underlie neurotoxin-induced cell death. They also suggest that, after mitochondrial release of cytochrome c in dopaminergic neurons after neurotoxin treatment, intracellular levels of ATP may constitute a critical factor in determining whether a neuron will die by a caspase-dependent or -independent pathway.
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Affiliation(s)
- Baek S Han
- Department of Biology, Yonsei University College of Science, Seodaemoon-Gu, Seoul 120-749, Korea
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291
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Abstract
A number of reports indicate the potential for redox signalling via extracellular signal-regulated protein kinases (ERK) during neuronal injury. We have previously found that sustained ERK activation contributes to toxicity elicited by 6-hydroxydopamine (6-OHDA) in the B65 neuronal cell line. To determine whether reactive oxygen species (ROS) play a role in mediating ERK activation and 6-OHDA toxicity, we examined the effects of catalase, superoxide dismutase (SOD1), and metalloporphyrin antioxidants ('SOD mimetics') on 6-OHDA-treated cells. We found that catalase and metalloporphyrin antioxidants not only conferred protection against 6-OHDA but also inhibited development of sustained ERK phosphorylation in both differentiated and undifferentiated B65 cells. However, exogenously added SOD1 and heat-inactivated catalase had no effect on either toxicity or sustained ERK phosphorylation. This correlation between antioxidant protection and inhibition of 6-OHDA-induced sustained ERK phosphorylation suggests that redox regulation of ERK signalling cascades may contribute to neuronal toxicity.
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292
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Ryu EJ, Harding HP, Angelastro JM, Vitolo OV, Ron D, Greene LA. Endoplasmic reticulum stress and the unfolded protein response in cellular models of Parkinson's disease. J Neurosci 2002; 22:10690-8. [PMID: 12486162 PMCID: PMC6758450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2023] Open
Abstract
6-hydroxydopamine, 1-methyl-4-phenyl-pyridinium (MPP+), and rotenone cause the death of dopaminergic neurons in vitro and in vivo and are widely used to model Parkinson's disease. To identify regulated genes in such models, we performed serial analysis of gene expression on neuronal PC12 cells exposed to 6-hydroxydopamine. This revealed a striking increase in transcripts associated with the unfolded protein response. Immunoblotting confirmed phosphorylation of the key endoplasmic reticulum stress kinases IRE1alpha and PERK (PKR-like ER kinase) and induction of their downstream targets. There was a similar response to MPP+ and rotenone, but not to other apoptotic initiators. As evidence that endoplasmic reticulum stress contributes to neuronal death, sympathetic neurons from PERK null mice in which the capacity to respond to endoplasmic reticulum stress is compromised were more sensitive to 6-hydroxydopamine. Our findings, coupled with evidence from familial forms of Parkinson's disease, raise the possibility of widespread involvement of endoplasmic reticulum stress and the unfolded protein response in the pathophysiology of this disease.
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Affiliation(s)
- Elizabeth J Ryu
- Department of Pathology, Center for Neurobiology and Behavior, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University College of Physicians and Surgeons, New York, New York 10032, USA
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293
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Zoli M, Moretti M, Zanardi A, McIntosh JM, Clementi F, Gotti C. Identification of the nicotinic receptor subtypes expressed on dopaminergic terminals in the rat striatum. J Neurosci 2002; 22:8785-9. [PMID: 12388584 PMCID: PMC6757689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/26/2023] Open
Abstract
Neuronal nicotinic acetylcholine receptors (nAChRs) expressed on mesostriatal dopaminergic neurons are thought to mediate several behavioral effects of nicotine, including locomotion, habit learning, and reinforcement. Using immunoprecipitation and ligand-binding techniques, we have shown that both alpha6beta2* and alpha4(nonalpha6)beta2* nAChRs are expressed in the caudate-putamen and that only alpha6* nAChRs can bind alpha-conotoxin MII and methyllycaconitine with affinities of 1.3 and 40 nm, respectively. Further studies performed on 6-hydroxydopamine-lesioned striatum led to the identification of nAChR subtypes selectively expressed on dopaminergic terminals [alpha4alpha5beta2, alpha4alpha6beta2(beta3), and alpha6beta2(beta3)], nondopaminergic neuronal structures (alpha2alpha4beta2), or both structures (alpha4beta2). The identification of the nAChRs expressed on striatal dopaminergic terminals opens up the possibility of developing selective nAChR ligands active on dopaminergic systems and associated diseases, such as Parkinson's disease.
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Affiliation(s)
- Michele Zoli
- Department of Biomedical Sciences, Section of Physiology, University of Modena and Reggio Emilia, 41100 Modena, Italy
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294
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Espejo EF, Gonzalez-Albo MC, Moraes JP, El Banoua F, Flores JA, Caraballo I. Functional regeneration in a rat Parkinson's model after intrastriatal grafts of glial cell line-derived neurotrophic factor and transforming growth factor beta1-expressing extra-adrenal chromaffin cells of the Zuckerkandl's organ. J Neurosci 2001; 21:9888-95. [PMID: 11739596 PMCID: PMC6763029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023] Open
Abstract
Intrabrain transplantation of chromaffin cell aggregates of the Zuckerkandl's organ, an extra-adrenal paraganglion that has never been tested for antiparkinsonian treatment, induced gradual improvement of functional deficits in parkinsonian rats. These beneficial effects were related to long survival of grafted cells, striatal reinnervation, and enhancement of dopamine levels in grafted striatum. Grafted cells were not dopaminergics, but they expressed glial cell line-derived neurotrophic factor (GDNF) and transforming growth factor-beta(1). These factors were detected in the host striatal tissue, indicating that chromaffin cells secreted them after grafting. Because glial cell line-derived neurotrophic factor possesses neurorestorative properties over dopaminergic neurons, and transforming growth factor-beta(1) is a cofactor that potentiates the neurotrophic actions of GDNF, functional regeneration was likely caused by the chronic trophic action of neurotrophic factors delivered by long-surviving grafted cells. This work should stimulate research on the clinical applicability of transplants of the Zuckerkandl's organ in Parkinson's disease.
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Affiliation(s)
- E F Espejo
- Departamento de Fisiologia Medica y Biofisica, Universidad de Sevilla, E-41009 Sevilla, Spain.
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295
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Nikkhah G, Falkenstein G, Rosenthal C. Restorative plasticity of dopamine neuronal transplants depends on the degree of hemispheric dominance. J Neurosci 2001; 21:6252-63. [PMID: 11487648 PMCID: PMC6763163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
The ability of dopaminergic (DA) transplants to restore complex sensorimotor behaviors in experimental Parkinson's disease is dependent on graft survival and reinnervation and is likely to be further modified by complex functional graft-host interactions. Here, we examined the impact of hemispheric dominance and extensive testing regimes on the functional capabilities of DA transplants to restore skilled forelimb movements in rats with unilateral 6-hydroxydopamine lesions. Interestingly, a near complete recovery was observed in DA-grafted animals that did not exhibit a strong hemispheric lateralization for paw use before lesion and implantation surgery, whereas animals with a clear lateralization of paw use and grafted into the contralateral hemisphere exhibited only moderate recovery. Finally, animals grafted ipsilateral to the preferred paw were most resistant to functional improvements in skilled forelimb use. However, the influence of hemispheric dominance on the degree of functional DA graft-induced restoration was specific for skilled forelimb use, whereas no such differences were observed in other tests for motor and sensory functions related to the DA system. Furthermore, functional recovery of DA-grafted animals in skilled forelimb use was significantly promoted by extensive behavioral testing regimes indicative of a "learning how to use" the transplant effect. These findings indicate the importance of the underlying functional architecture of complex sensorimotor behaviors, such as skilled forelimb use, and the DA neurotransmitter system for the plasticity of DA transplants to promoting a more complete behavioral recovery in experimental, and potentially, also in clinical forms of Parkinson's disease.
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Affiliation(s)
- G Nikkhah
- Neurosurgical Clinic, Nordstadt Hospital, D-30167 Hannover, Germany.
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296
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Kirik D, Winkler C, Björklund A. Growth and functional efficacy of intrastriatal nigral transplants depend on the extent of nigrostriatal degeneration. J Neurosci 2001; 21:2889-96. [PMID: 11306640 PMCID: PMC6762534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
Previous studies have shown that the functional efficacy of intrastriatal transplants of fetal dopamine (DA) neurons in the rat Parkinson model depends on their ability to establish a new functional innervation of the denervated striatum. Here we report that the survival, growth, and function of the grafted DA neurons greatly depend on the severity of the lesion of the host nigrostriatal system. Fiber outgrowth, and to a lesser extent also cell survival, were significantly reduced in animals in which part of the intrinsic DA system was left intact. Moreover, graft-induced functional recovery, as assessed in the stepping, paw-use, and apomorphine rotation tests, was obtained only in severely lesioned animals, i.e., in rats with >70% DA denervation of the host striatum. Functional recovery seen in these animals in which the 6-hydroxydopamine (6-OHDA) lesion was confined to the striatum was more pronounced than that previously obtained in rats with complete lesions of the mesencephalic DA system, indicating that spared portions of the host DA system, particularly those innervating nonstriatal forebrain areas, may be necessary for the grafts to exert their optimal functional effect. These data have implications for the optimal use of fetal nigral transplants in Parkinson patients in different stages of the disease.
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Affiliation(s)
- D Kirik
- Wallenberg Neuroscience Center, Department of Physiological Sciences, Lund University, 22184, Lund, Sweden.
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297
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Ryan RE, Ross SA, Drago J, Loiacono RE. Dose-related neuroprotective effects of chronic nicotine in 6-hydroxydopamine treated rats, and loss of neuroprotection in alpha4 nicotinic receptor subunit knockout mice. Br J Pharmacol 2001; 132:1650-6. [PMID: 11309235 PMCID: PMC1572727 DOI: 10.1038/sj.bjp.0703989] [Citation(s) in RCA: 151] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The present study examined the effect of a range of doses of chronic nicotine (0.75, 1.5, 3.0 and 30.0 mg kg(-1) day(-1), s.c., 14 days) upon striatal dopaminergic nerve terminal survival following 6-hydroxydopamine (6-OHDA; 10 microg intrastriatal unilaterally) in rats; and the effects of acute nicotine (1 mg kg(-1), s.c.) pretreatment upon striatal neurodegeneration induced by methamphetamine (5 mg kg(-1), i.p., three doses at 2 h intervals) in wild-type and alpha4 nicotinic receptor (nAChR) subunit knockout mice. In both models of Parkinsonian-like damage, loss of striatal dopaminergic nerve terminals was assessed by [(3)H]-mazindol autoradiography. In rats, chronic nicotine infusion delivered by osmotic minipump implanted subcutaneously 7 days prior to intrastriatal 6-OHDA injection produced significant and dose-related protection against 6-OHDA-induced neurodegeneration. Low (0.75 and 1.5 mg kg(-1) day(-1)) but not high (3.0 and 30.0 mg kg(-1) day(-1)) nicotine doses significantly inhibited 6-OHDA-induced degeneration. In wild-type mice, acute nicotine treatment produced significant inhibition of methamphetamine-induced neurodegeneration. In alpha4 nAChR subunit knockout mice, acute nicotine treatment failed to inhibit methamphetamine-induced neurodegeneration. Nicotine is capable of protecting dopaminergic neurons against Parkinsonian-like neurodegeneration in vivo. In rats, this neuroprotective effect is critically dependent upon nicotine dose and is consistent with the activation of nAChRs, as high, desensitizing doses of nicotine fail to be neuroprotective. Further, neuroprotection is absent in alpha4 nAChR subunit knockout mice. The current results therefore suggest that activation of alpha4 subunit containing nAChRs constitutes a major component of the neuroprotective effect of nicotine upon Parkinsonian-like damage in vivo.
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Affiliation(s)
- R E Ryan
- Department of Pharmaceutical Biology and Pharmacology, Victorian College of Pharmacy, Monash University, Parkville, Victoria 3052, Australia.
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298
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Kirik D, Rosenblad C, Bjorklund A, Mandel RJ. Long-term rAAV-mediated gene transfer of GDNF in the rat Parkinson's model: intrastriatal but not intranigral transduction promotes functional regeneration in the lesioned nigrostriatal system. J Neurosci 2000; 20:4686-700. [PMID: 10844038 PMCID: PMC6772474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2000] [Revised: 03/17/2000] [Accepted: 03/27/2000] [Indexed: 02/16/2023] Open
Abstract
Previous studies have used recombinant adeno-associated viral (rAAV) vectors to deliver glial cell line-derived neurotrophic factor (GDNF) in the substantia nigra to protect the nigral dopamine (DA) neurons from 6-hydroxydopamine-induced damage. However, no regeneration or functional recovery was observed in these experiments. Here, we have used an rAAV-GDNF vector to express GDNF long-term (6 months) in either the nigral DA neurons themselves, in the striatal target cells, or in both of these structures. The results demonstrate that both nigral and striatal transduction provide significant protection of nigral DA neurons against the toxin-induced degeneration. However, only the rats receiving rAAV-GDNF in the striatum displayed behavioral recovery, accompanied by significant reinnervation of the lesioned striatum, which developed gradually over the first 4-5 months after the lesion. GDNF transgene expression was maintained at high levels throughout this period. These results provide evidence that rAAV is a highly efficient vector system for long-term expression of therapeutic proteins in the nigrostriatal system.
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Affiliation(s)
- D Kirik
- Wallenberg Neuroscience Center, Department of Physiological Sciences, Division of Neurobiology, Lund University, 223 62 Lund, Sweden.
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299
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Schicatano EJ, Peshori KR, Gopalaswamy R, Sahay E, Evinger C. Reflex excitability regulates prepulse inhibition. J Neurosci 2000; 20:4240-7. [PMID: 10818160 PMCID: PMC6772660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
Presentation of a weak stimulus, a prepulse, before a reflex-evoking stimulus decreases the amplitude of the reflex response relative to reflex amplitude evoked without a preceding prepulse. For example, presenting a brief tone before a trigeminal blink-eliciting stimulus significantly reduces reflex blink amplitude. A common explanation of such data are that sensory processing of the prepulse modifies reflex circuit behavior. The current study investigates the converse hypothesis that the intrinsic characteristics of the reflex circuit rather than prepulse processing determine prepulse modification of trigeminal and acoustic reflex blinks. Unilateral lesions of substantia nigra pars compacta neurons created rats with hyperexcitable trigeminal reflex blinks but normally excitable acoustic reflex blinks. In control rats, presentation of a prepulse reduced the amplitude of both trigeminal and acoustic reflex blinks. In 6-OHDA-lesioned rats, however, the same acoustic prepulse facilitated trigeminal reflex blinks but inhibited acoustic reflex blinks. The magnitude of prepulse modification correlated with reflex excitability. Humans exhibited the same pattern of prepulse modification. An acoustic prepulse facilitated the trigeminal reflex blinks of subjects with hyperexcitable trigeminal reflex blinks caused by Parkinson's disease. The same prepulse inhibited trigeminal reflex blinks of age-matched control subjects. Prepulse modification also correlated with trigeminal reflex blink excitability. These data show that reflex modification by a prepulse reflects the intrinsic characteristics of the reflex circuit rather than an external adjustment of the reflex circuit by the prepulse.
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Affiliation(s)
- E J Schicatano
- Department of Psychology, Wilkes University, Wilkes-Barre, Pennsylvania 18766, USA
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300
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Cass WA, Manning MW. GDNF protection against 6-OHDA-induced reductions in potassium-evoked overflow of striatal dopamine. J Neurosci 1999; 19:1416-23. [PMID: 9952418 PMCID: PMC6786039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
Abstract
Glial cell line-derived neurotrophic factor (GDNF), when administered before 6-hydroxydopamine (6-OHDA), has been shown to prevent the reduction in nigral dopamine (DA) levels and tyrosine hydroxylase-positive neurons normally observed after 6-OHDA lesions. The present study examined the ability of GDNF to prevent 6-OHDA-induced reductions in striatal DA release and reductions in striatal and nigral DA levels. GDNF (10 micrograms), or vehicle, was injected into the right nigra of anesthetized male Fischer-344 rats and was followed 6 hr later by intranigral 6-OHDA or saline. Three to four weeks later the animals were anesthetized with urethane and prepared for in vivo electrochemistry. Potassium-evoked overflow of DA was dramatically decreased in the right striatum of the vehicle + 6-OHDA-treated animals. GDNF appeared to prevent the reduction in evoked overflow of DA in the right striatum of the 6-OHDA-treated animals. However, in comparison with that in animals that received GDNF + saline, the overflow of DA was significantly reduced in the GDNF + 6-OHDA animals. Similarly, although nigral levels of DA were above normal in the GDNF + 6-OHDA-treated animals, they were below DA levels found in GDNF + saline-treated rats. Striatal DA levels were partially protected by GDNF. In animals examined 10-12 weeks after the GDNF and 6-OHDA treatments, the apparent protective ability of GDNF on the evoked overflow of DA in the striatum was diminished. Thus, although intranigral GDNF can prevent 6-OHDA-induced reductions in nigral DA levels, long-term protection of the evoked overflow of DA in the striatum is minimal.
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Affiliation(s)
- W A Cass
- Department of Anatomy and Neurobiology, University of Kentucky College of Medicine, Lexington, Kentucky 40536-0298, USA
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