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Oliveira BDS, Toscano ECDB, Abreu LKS, Fernandes HDB, Amorim RF, Ferreira RN, Machado CA, Carvalho BC, da Silva MCM, de Oliveira ACP, Rachid MA, Rocha NP, Teixeira AL, da Silva ER, de Miranda AS. Nigrostriatal Inflammation Is Associated with Nonmotor Symptoms in an Experimental Model of Prodromal Parkinson's Disease. Neuroscience 2024; 549:65-75. [PMID: 38750924 DOI: 10.1016/j.neuroscience.2024.05.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Revised: 04/17/2024] [Accepted: 05/09/2024] [Indexed: 05/21/2024]
Abstract
Recent evidence has supported a pathogenic role for neuroinflammation in Parkinson's disease (PD). Inflammatory response has been associated with symptoms and subtypes of PD. However, it is unclear whether immune changes are involved in the initial pathogenesis of PD, leading to the non-motor symptoms (NMS) observed in its prodromal stage. The current study aimed to characterize the behavioral and cognitive changes in a toxin-induced model of prodromal PD-like syndrome. We also sought to investigate the role of neuroinflammation in prodromal PD-related NMS. Male mice were subjected to bilateral intranasal infusion with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) or saline (control group), followed by comprehensive behavioral, pathological and neurochemical analysis. Intranasal MPTP infusion was able to cause the loss of dopaminergic neurons in the substantia nigra (SN). In parallel, it induced impairment in olfactory discrimination and social memory consolidation, compulsive and anxiety-like behaviors, but did not influence motor performance. Iba-1 and GFAP expressions were increased in the SN, suggesting an activated state of microglia and astrocytes. Consistent with this, MPTP mice had increased levels of IL-10 and IL-17A, and decreased levels of BDNF and TrkA mRNA in the SN. The striatum showed increased IL-17A, BDNF, and NFG levels compared to control mice. In conclusion, neuroinflammation may play an important role in the early stage of experimental PD-like syndrome, leading to cognitive and behavioral changes. Our results also indicate that intranasal administration of MPTP may represent a valuable mouse model for prodromal PD.
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Affiliation(s)
- Bruna da Silva Oliveira
- Laboratório de Neurobiologia "Conceição Machado", Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Eliana Cristina de Brito Toscano
- Departamento de Patologia, Faculdade de Medicina, Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil; Programa de Pós-graduação em Saúde, Faculdade de Medicina, Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil
| | - Larissa Katharina Sabino Abreu
- Laboratório de Neurobiologia "Conceição Machado", Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Heliana de Barros Fernandes
- Laboratório de Neurobiologia "Conceição Machado", Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Renan Florindo Amorim
- Laboratório de Neurobiologia "Conceição Machado", Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Rodrigo Novaes Ferreira
- Laboratório de Neurobiologia "Conceição Machado", Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Caroline Amaral Machado
- Laboratório de Neurobiologia "Conceição Machado", Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Brener Cunha Carvalho
- Laboratório de Genes Inflamatórios, Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Maria Carolina Machado da Silva
- Laboratório de Neurofarmacologia, Departamento de Farmacologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Antônio Carlos Pinheiro de Oliveira
- Laboratório de Neurofarmacologia, Departamento de Farmacologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Milene Alvarenga Rachid
- Laboratório de Patologia Celular e Molecular, Departamento de Patologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Brazil
| | - Natália Pessoa Rocha
- Department of Neurology, McGovern Medical School, The University of Texas Health Science Center at Houston, TX, USA
| | - Antônio Lúcio Teixeira
- Instituto de Ensino e Pesquisa, Santa Casa BH, Belo Horizonte, Brazil; Neuropsychiatry Program, Department of Psychiatry and Behavioral Sciences, University of Texas Health Science Center at Houston, TX, USA
| | - Elizabeth Ribeiro da Silva
- Laboratório de Neurobiologia "Conceição Machado", Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Aline Silva de Miranda
- Laboratório de Neurobiologia "Conceição Machado", Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
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Rocha GS, Freire MAM, Paiva KM, Oliveira RF, Morais PLAG, Santos JR, Cavalcanti JRLP. The neurobiological effects of senescence on dopaminergic system: A comprehensive review. J Chem Neuroanat 2024; 137:102415. [PMID: 38521203 DOI: 10.1016/j.jchemneu.2024.102415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 02/26/2024] [Accepted: 03/15/2024] [Indexed: 03/25/2024]
Abstract
Over time, the body undergoes a natural, multifactorial, and ongoing process named senescence, which induces changes at the molecular, cellular, and micro-anatomical levels in many body systems. The brain, being a highly complex organ, is particularly affected by this process, potentially impairing its numerous functions. The brain relies on chemical messengers known as neurotransmitters to function properly, with dopamine being one of the most crucial. This catecholamine is responsible for a broad range of critical roles in the central nervous system, including movement, learning, cognition, motivation, emotion, reward, hormonal release, memory consolidation, visual performance, sexual drive, modulation of circadian rhythms, and brain development. In the present review, we thoroughly examine the impact of senescence on the dopaminergic system, with a primary focus on the classic delimitations of the dopaminergic nuclei from A8 to A17. We provide in-depth information about their anatomy and function, particularly addressing how senescence affects each of these nuclei.
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Affiliation(s)
- Gabriel S Rocha
- Behavioral and Evolutionary Neurobiology Laboratory, Federal University of Sergipe (UFS), Itabaiana, Brazil
| | - Marco Aurelio M Freire
- Behavioral and Evolutionary Neurobiology Laboratory, Federal University of Sergipe (UFS), Itabaiana, Brazil
| | - Karina M Paiva
- Laboratory of Experimental Neurology, State University of Rio Grande do Norte (UERN), Mossoró, Brazil
| | - Rodrigo F Oliveira
- Laboratory of Experimental Neurology, State University of Rio Grande do Norte (UERN), Mossoró, Brazil
| | - Paulo Leonardo A G Morais
- Laboratory of Experimental Neurology, State University of Rio Grande do Norte (UERN), Mossoró, Brazil
| | - José Ronaldo Santos
- Behavioral and Evolutionary Neurobiology Laboratory, Federal University of Sergipe (UFS), Itabaiana, Brazil
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3
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Linking Cerebrovascular Dysfunction to Age-Related Hearing Loss and Alzheimer’s Disease—Are Systemic Approaches for Diagnosis and Therapy Required? Biomolecules 2022; 12:biom12111717. [DOI: 10.3390/biom12111717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 11/09/2022] [Accepted: 11/17/2022] [Indexed: 11/22/2022] Open
Abstract
Alzheimer’s disease (AD), the most common cause of dementia in the elderly, is a neurodegenerative disorder associated with neurovascular dysfunction, cognitive decline, and the accumulation of amyloid β peptide (Aβ) in the brain and tau-related lesions in neurons termed neurofibrillary tangles (NFTs). Aβ deposits and NFT formation are the central pathological hallmarks in AD brains, and the majority of AD cases have been shown to exhibit a complex combination of systemic comorbidities. While AD is the foremost common cause of dementia in the elderly, age-related hearing loss (ARHL) is the most predominant sensory deficit in the elderly. During aging, chronic inflammation and resulting endothelial dysfunction have been described and might be key contributors to AD; we discuss an intriguing possible link between inner ear strial microvascular pathology and blood–brain barrier pathology and present ARHL as a potentially modifiable and treatable risk factor for AD development. We present compelling evidence that ARHL might well be seen as an important risk factor in AD development: progressive hearing impairment, leading to social isolation, and its comorbidities, such as frailty, falls, and late-onset depression, link ARHL with cognitive decline and increased risk of dementia, rendering it tempting to speculate that ARHL might be a potential common molecular and pathological trigger for AD. Additionally, one could speculate that amyloid-beta might damage the blood–labyrinth barrier as it does to the blood–brain barrier, leading to ARHL pathology. Finally, there are options for the treatment of ARHL by targeted neurotrophic factor supplementation to the cochlea to improve cognitive outcomes; they can also prevent AD development and AD-related comorbidity in the future.
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Klæstrup IH, Just MK, Holm KL, Alstrup AKO, Romero-Ramos M, Borghammer P, Van Den Berge N. Impact of aging on animal models of Parkinson's disease. Front Aging Neurosci 2022; 14:909273. [PMID: 35966779 PMCID: PMC9366194 DOI: 10.3389/fnagi.2022.909273] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 06/28/2022] [Indexed: 11/23/2022] Open
Abstract
Aging is the biggest risk factor for developing Parkinson's disease (PD), the second most common neurodegenerative disorder. Several animal models have been developed to explore the pathophysiology underlying neurodegeneration and the initiation and spread of alpha-synuclein-related PD pathology, and to investigate biomarkers and therapeutic strategies. However, bench-to-bedside translation of preclinical findings remains suboptimal and successful disease-modifying treatments remain to be discovered. Despite aging being the main risk factor for developing idiopathic PD, most studies employ young animals in their experimental set-up, hereby ignoring age-related cellular and molecular mechanisms at play. Consequently, studies in young animals may not be an accurate reflection of human PD, limiting translational outcomes. Recently, it has been shown that aged animals in PD research demonstrate a higher susceptibility to developing pathology and neurodegeneration, and present with a more disseminated and accelerated disease course, compared to young animals. Here we review recent advances in the investigation of the role of aging in preclinical PD research, including challenges related to aged animal models that are limiting widespread use. Overall, current findings indicate that the use of aged animals may be required to account for age-related interactions in PD pathophysiology. Thus, although the use of older animals has disadvantages, a model that better represents clinical disease within the elderly would be more beneficial in the long run, as it will increase translational value and minimize the risk of therapies failing during clinical studies. Furthermore, we provide recommendations to manage the challenges related to aged animal models.
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Affiliation(s)
- Ida Hyllen Klæstrup
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
- DANDRITE-Danish Research Institute of Translational Neuroscience, Nordic-EMBL Partnership for Molecular Medicine, Aarhus University, Aarhus, Denmark
| | - Mie Kristine Just
- Institute for Clinical Medicine, Aarhus University, Aarhus, Denmark
- Nuclear Medicine and PET, Aarhus University Hospital, Aarhus, Denmark
| | | | - Aage Kristian Olsen Alstrup
- Institute for Clinical Medicine, Aarhus University, Aarhus, Denmark
- Nuclear Medicine and PET, Aarhus University Hospital, Aarhus, Denmark
| | - Marina Romero-Ramos
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
- DANDRITE-Danish Research Institute of Translational Neuroscience, Nordic-EMBL Partnership for Molecular Medicine, Aarhus University, Aarhus, Denmark
| | - Per Borghammer
- Institute for Clinical Medicine, Aarhus University, Aarhus, Denmark
- Nuclear Medicine and PET, Aarhus University Hospital, Aarhus, Denmark
| | - Nathalie Van Den Berge
- Institute for Clinical Medicine, Aarhus University, Aarhus, Denmark
- Nuclear Medicine and PET, Aarhus University Hospital, Aarhus, Denmark
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Szarowicz CA, Steece-Collier K, Caulfield ME. New Frontiers in Neurodegeneration and Regeneration Associated with Brain-Derived Neurotrophic Factor and the rs6265 Single Nucleotide Polymorphism. Int J Mol Sci 2022; 23:ijms23148011. [PMID: 35887357 PMCID: PMC9319713 DOI: 10.3390/ijms23148011] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 07/11/2022] [Accepted: 07/12/2022] [Indexed: 11/20/2022] Open
Abstract
Brain-derived neurotrophic factor is an extensively studied neurotrophin implicated in the pathology of multiple neurodegenerative and psychiatric disorders including, but not limited to, Parkinson’s disease, Alzheimer’s disease, Huntington’s disease, traumatic brain injury, major de-pressive disorder, and schizophrenia. Here we provide a brief summary of current knowledge on the role of BDNF and the common human single nucleotide polymorphism, rs6265, in driving the pathogenesis and rehabilitation in these disorders, as well as the status of BDNF-targeted therapies. A common trend has emerged correlating low BDNF levels, either detected within the central nervous system or peripherally, to disease states, suggesting that BDNF replacement therapies may hold clinical promise. In addition, we introduce evidence for a distinct role of the BDNF pro-peptide as a biologically active ligand and the need for continuing studies on its neurological function outside of that as a molecular chaperone. Finally, we highlight the latest research describing the role of rs6265 expression in mechanisms of neurodegeneration as well as paradoxical advances in the understanding of this genetic variant in neuroregeneration. All of this is discussed in the context of personalized medicine, acknowledging there is no “one size fits all” therapy for neurodegenerative or psychiatric disorders and that continued study of the multiple BDNF isoforms and genetic variants represents an avenue for discovery ripe with therapeutic potential.
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Affiliation(s)
- Carlye A. Szarowicz
- Department of Translational Neuroscience, College of Human Medicine, Michigan State University, Grand Rapids, MI 49503, USA; (C.A.S.); (K.S.-C.)
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI 48824, USA
| | - Kathy Steece-Collier
- Department of Translational Neuroscience, College of Human Medicine, Michigan State University, Grand Rapids, MI 49503, USA; (C.A.S.); (K.S.-C.)
| | - Margaret E. Caulfield
- Department of Translational Neuroscience, College of Human Medicine, Michigan State University, Grand Rapids, MI 49503, USA; (C.A.S.); (K.S.-C.)
- Correspondence: ; Tel.: +1-616-234-0969; Fax: +1- 616-234-0991
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Connolly MG, Bruce SR, Kohman RA. Exercise duration differentially effects age-related neuroinflammation and hippocampal neurogenesis. Neuroscience 2022; 490:275-286. [PMID: 35331843 PMCID: PMC9038708 DOI: 10.1016/j.neuroscience.2022.03.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 03/10/2022] [Accepted: 03/16/2022] [Indexed: 12/14/2022]
Abstract
The physiological effects of exercise vary as a function of frequency and length. However, research on the duration-dependent effects of exercise has focused primarily on young adults and less is known about the influence of exercise duration in the aged. The current study compared the effects of short-term and long-term running wheel access on hippocampal neurogenesis and neuroimmune markers in aged (19-23 months) male C57BL/6J mice. Aged mice were given 24-hour access to a running wheel for 14 days (short-term) or 51 days (long-term). Groups of non-running aged and young (5 months) mice served as comparison groups to detect age-related differences and effects of exercise. Long-term, but not short-term, exercise increased hippocampal neurogenesis as assessed by number of doublecortin (DCX) positive cells in the granular cell layer. Assessment of cytokines, receptors, and glial-activation markers showed the expected age-related increase compared to young controls. In the aged, exercise as a function of duration regulated select aspects of the neuroimmune profile. For instance, hippocampal expression of interleukin (IL)-10 was increased only following long-term exercise. While in contrast brain levels of IL-6 were reduced by both short- and long-term exercise. Additional findings showed that exercise does not modulate all aspects of age-related neuroinflammation and/or may have differential effects in hippocampal compared to brain samples. Overall, the data indicate that increasing exercise duration produces more robust effects on immune modulation and hippocampal neurogenesis.
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Affiliation(s)
- Meghan G Connolly
- University of Illinois Urbana-Champaign, Department of Animal Sciences, Champaign, IL, USA.
| | - Spencer R Bruce
- University of North Carolina Wilmington, Department of Psychology, Wilmington, NC, USA.
| | - Rachel A Kohman
- University of North Carolina Wilmington, Department of Psychology, Wilmington, NC, USA.
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7
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Shityakov S, Hayashi K, Störk S, Scheper V, Lenarz T, Förster CY. The Conspicuous Link between Ear, Brain and Heart-Could Neurotrophin-Treatment of Age-Related Hearing Loss Help Prevent Alzheimer's Disease and Associated Amyloid Cardiomyopathy? Biomolecules 2021; 11:biom11060900. [PMID: 34204299 PMCID: PMC8235707 DOI: 10.3390/biom11060900] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 06/05/2021] [Accepted: 06/14/2021] [Indexed: 12/23/2022] Open
Abstract
Alzheimer's disease (AD), the most common cause of dementia in the elderly, is a neurodegenerative disorder associated with neurovascular dysfunction and cognitive decline. While the deposition of amyloid β peptide (Aβ) and the formation of neurofibrillary tangles (NFTs) are the pathological hallmarks of AD-affected brains, the majority of cases exhibits a combination of comorbidities that ultimately lead to multi-organ failure. Of particular interest, it can be demonstrated that Aβ pathology is present in the hearts of patients with AD, while the formation of NFT in the auditory system can be detected much earlier than the onset of symptoms. Progressive hearing impairment may beget social isolation and accelerate cognitive decline and increase the risk of developing dementia. The current review discusses the concept of a brain-ear-heart axis by which Aβ and NFT inhibition could be achieved through targeted supplementation of neurotrophic factors to the cochlea and the brain. Such amyloid inhibition might also indirectly affect amyloid accumulation in the heart, thus reducing the risk of developing AD-associated amyloid cardiomyopathy and cardiovascular disease.
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Affiliation(s)
- Sergey Shityakov
- Department of Anaesthesiology, Intensive Care, Emergency and Pain Medicine, University Hospital Würzburg, D-97080 Würzburg, Germany;
- Infochemistry Scientific Center, Laboratory of Chemoinformatics, ITMO University, 191002 Saint-Petersburg, Russia
| | - Kentaro Hayashi
- Advanced Stroke Center, Shimane University Hospital, 89-1 Enya, Shimane, Izumo 693-8501, Japan;
| | - Stefan Störk
- Comprehensive Heart Failure Q9 Center, University of Würzburg, D-97080 Würzburg, Germany;
| | - Verena Scheper
- Department of Otolaryngology, Hannover Medical School and Cluster of Excellence “Hearing4All”, 30625 Hannover, Germany;
| | - Thomas Lenarz
- Department of Otolaryngology, Hannover Medical School and Cluster of Excellence “Hearing4All”, 30625 Hannover, Germany;
- Correspondence: (T.L.); (C.Y.F.)
| | - Carola Y. Förster
- Department of Anaesthesiology, Intensive Care, Emergency and Pain Medicine, University Hospital Würzburg, D-97080 Würzburg, Germany;
- Correspondence: (T.L.); (C.Y.F.)
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Johnstone DM, Hamilton C, Gordon LC, Moro C, Torres N, Nicklason F, Stone J, Benabid AL, Mitrofanis J. Exploring the Use of Intracranial and Extracranial (Remote) Photobiomodulation Devices in Parkinson's Disease: A Comparison of Direct and Indirect Systemic Stimulations. J Alzheimers Dis 2021; 83:1399-1413. [PMID: 33843683 DOI: 10.3233/jad-210052] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
In recent times, photobiomodulation has been shown to be beneficial in animal models of Parkinson's disease, improving locomotive behavior and being neuroprotective. Early observations in people with Parkinson's disease have been positive also, with improvements in the non-motor symptoms of the disease being evident most consistently. Although the precise mechanisms behind these improvements are not clear, two have been proposed: direct stimulation, where light reaches and acts directly on the distressed neurons, and remote stimulation, where light influences cells and/or molecules that provide systemic protection, thereby acting indirectly on distressed neurons. In relation to Parkinson's disease, given that the major zone of pathology lies deep in the brain and that light from an extracranial or external photobiomodulation device would not reach these vulnerable regions, stimulating the distressed neurons directly would require intracranial delivery of light using a device implanted close to the vulnerable regions. For indirect systemic stimulation, photobiomodulation could be applied to either the head and scalp, using a transcranial helmet, or to a more remote body part (e.g., abdomen, leg). In this review, we discuss the evidence for both the direct and indirect neuroprotective effects of photobiomodulation in Parkinson's disease and propose that both types of treatment modality, when working together using both intracranial and extracranial devices, provide the best therapeutic option.
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Affiliation(s)
| | | | - Luke C Gordon
- Department of Physiology, University of Sydney, Australia
| | - Cecile Moro
- University Grenoble Alpes, CEA, LETI, CLINATEC, MINATEC Campus, Grenoble, France
| | - Napoleon Torres
- University Grenoble Alpes, CEA, LETI, CLINATEC, MINATEC Campus, Grenoble, France
| | - Frank Nicklason
- Department of Anatomy, University of Sydney, Australia.,Geriatric Medicine, Royal Hobart Hospital, Hobart, Australia
| | - Jonathan Stone
- Department of Physiology, University of Sydney, Australia
| | - Alim-Louis Benabid
- University Grenoble Alpes, CEA, LETI, CLINATEC, MINATEC Campus, Grenoble, France
| | - John Mitrofanis
- Department of Anatomy, University of Sydney, Australia.,University Grenoble Alpes, CEA, LETI, CLINATEC, MINATEC Campus, Grenoble, France
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Ferrini F, Salio C, Boggio EM, Merighi A. Interplay of BDNF and GDNF in the Mature Spinal Somatosensory System and Its Potential Therapeutic Relevance. Curr Neuropharmacol 2021; 19:1225-1245. [PMID: 33200712 PMCID: PMC8719296 DOI: 10.2174/1570159x18666201116143422] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 09/17/2020] [Accepted: 10/05/2020] [Indexed: 11/22/2022] Open
Abstract
The growth factors BDNF and GDNF are gaining more and more attention as modulators of synaptic transmission in the mature central nervous system (CNS). The two molecules undergo a regulated secretion in neurons and may be anterogradely transported to terminals where they can positively or negatively modulate fast synaptic transmission. There is today a wide consensus on the role of BDNF as a pro-nociceptive modulator, as the neurotrophin has an important part in the initiation and maintenance of inflammatory, chronic, and/or neuropathic pain at the peripheral and central level. At the spinal level, BDNF intervenes in the regulation of chloride equilibrium potential, decreases the excitatory synaptic drive to inhibitory neurons, with complex changes in GABAergic/glycinergic synaptic transmission, and increases excitatory transmission in the superficial dorsal horn. Differently from BDNF, the role of GDNF still remains to be unraveled in full. This review resumes the current literature on the interplay between BDNF and GDNF in the regulation of nociceptive neurotransmission in the superficial dorsal horn of the spinal cord. We will first discuss the circuitries involved in such a regulation, as well as the reciprocal interactions between the two factors in nociceptive pathways. The development of small molecules specifically targeting BDNF, GDNF and/or downstream effectors is opening new perspectives for investigating these neurotrophic factors as modulators of nociceptive transmission and chronic pain. Therefore, we will finally consider the molecules of (potential) pharmacological relevance for tackling normal and pathological pain.
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Affiliation(s)
- Francesco Ferrini
- Department of Veterinary Sciences, University of Turin, Grugliasco, Italy
- Department of Psychiatry & Neuroscience, Université Laval, Québec, Canada
| | - Chiara Salio
- Department of Veterinary Sciences, University of Turin, Grugliasco, Italy
| | - Elena M. Boggio
- Department of Veterinary Sciences, University of Turin, Grugliasco, Italy
| | - Adalberto Merighi
- Department of Veterinary Sciences, University of Turin, Grugliasco, Italy
- National Institute of Neuroscience, Grugliasco, Italy
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10
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Barata-Antunes S, Teixeira FG, Mendes-Pinheiro B, Domingues AV, Vilaça-Faria H, Marote A, Silva D, Sousa RA, Salgado AJ. Impact of Aging on the 6-OHDA-Induced Rat Model of Parkinson's Disease. Int J Mol Sci 2020; 21:ijms21103459. [PMID: 32422916 PMCID: PMC7279033 DOI: 10.3390/ijms21103459] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 05/09/2020] [Accepted: 05/10/2020] [Indexed: 01/14/2023] Open
Abstract
Parkinson's disease (PD) is the second most common age-related neurodegenerative disorder. The neurodegeneration leading to incapacitating motor abnormalities mainly occurs in the nigrostriatal pathway due to the loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc). Several animal models have been developed not only to better understand the mechanisms underlying neurodegeneration but also to test the potential of emerging disease-modifying therapies. However, despite aging being the main risk factor for developing idiopathic PD, most of the studies do not use aged animals. Therefore, this study aimed at assessing the effect of aging in the unilateral 6-hydroxydopamine (6-OHDA)-induced animal model of PD. For this, female young adult and aged rats received a unilateral injection of 6-OHDA into the medial forebrain bundle. Subsequently, the impact of aging on 6-OHDA-induced effects on animal welfare, motor performance, and nigrostriatal integrity were assessed. The results showed that aging had a negative impact on animal welfare after surgery. Furthermore, 6-OHDA-induced impairments on skilled motor function were significantly higher in aged rats when compared with their younger counterparts. Nigrostriatal histological analysis further revealed an increased 6-OHDA-induced dopaminergic cell loss in the SNpc of aged animals when compared to young animals. Overall, our results demonstrate a higher susceptibility of aged animals to 6-OHDA toxic insult.
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Affiliation(s)
- Sandra Barata-Antunes
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; (S.B.-A.); (F.G.T.); (B.M.-P.); (A.V.D.); (H.V.-F.); (A.M.); (D.S.)
- ICVS/3B’s—PT Government Associate Laboratory, 4710-057/4805-017 Braga/Guimarães, Portugal
| | - Fábio G. Teixeira
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; (S.B.-A.); (F.G.T.); (B.M.-P.); (A.V.D.); (H.V.-F.); (A.M.); (D.S.)
- ICVS/3B’s—PT Government Associate Laboratory, 4710-057/4805-017 Braga/Guimarães, Portugal
| | - Bárbara Mendes-Pinheiro
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; (S.B.-A.); (F.G.T.); (B.M.-P.); (A.V.D.); (H.V.-F.); (A.M.); (D.S.)
- ICVS/3B’s—PT Government Associate Laboratory, 4710-057/4805-017 Braga/Guimarães, Portugal
| | - Ana V. Domingues
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; (S.B.-A.); (F.G.T.); (B.M.-P.); (A.V.D.); (H.V.-F.); (A.M.); (D.S.)
- ICVS/3B’s—PT Government Associate Laboratory, 4710-057/4805-017 Braga/Guimarães, Portugal
| | - Helena Vilaça-Faria
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; (S.B.-A.); (F.G.T.); (B.M.-P.); (A.V.D.); (H.V.-F.); (A.M.); (D.S.)
- ICVS/3B’s—PT Government Associate Laboratory, 4710-057/4805-017 Braga/Guimarães, Portugal
| | - Ana Marote
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; (S.B.-A.); (F.G.T.); (B.M.-P.); (A.V.D.); (H.V.-F.); (A.M.); (D.S.)
- ICVS/3B’s—PT Government Associate Laboratory, 4710-057/4805-017 Braga/Guimarães, Portugal
| | - Deolinda Silva
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; (S.B.-A.); (F.G.T.); (B.M.-P.); (A.V.D.); (H.V.-F.); (A.M.); (D.S.)
- ICVS/3B’s—PT Government Associate Laboratory, 4710-057/4805-017 Braga/Guimarães, Portugal
| | - Rui A. Sousa
- Stemmatters, Biotecnologia e Medicina Regenerativa SA, 4805-017 Guimarães, Portugal;
| | - António J. Salgado
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; (S.B.-A.); (F.G.T.); (B.M.-P.); (A.V.D.); (H.V.-F.); (A.M.); (D.S.)
- ICVS/3B’s—PT Government Associate Laboratory, 4710-057/4805-017 Braga/Guimarães, Portugal
- Correspondence: ; Tel.: +351-253-60-4947; Fax: +351-253-60-4809
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11
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Houlton J, Abumaria N, Hinkley SFR, Clarkson AN. Therapeutic Potential of Neurotrophins for Repair After Brain Injury: A Helping Hand From Biomaterials. Front Neurosci 2019; 13:790. [PMID: 31427916 PMCID: PMC6688532 DOI: 10.3389/fnins.2019.00790] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 07/15/2019] [Indexed: 12/17/2022] Open
Abstract
Stroke remains the leading cause of long-term disability with limited options available to aid in recovery. Significant effort has been made to try and minimize neuronal damage following stroke with use of neuroprotective agents, however, these treatments have yet to show clinical efficacy. Regenerative interventions have since become of huge interest as they provide the potential to restore damaged neural tissue without being limited by a narrow therapeutic window. Neurotrophins, such as brain-derived neurotrophic factor (BDNF), and their high affinity receptors are actively produced throughout the brain and are involved in regulating neuronal activity and normal day-to-day function. Furthermore, neurotrophins are known to play a significant role in both protection and recovery of function following neurodegenerative diseases such as stroke and traumatic brain injury (TBI). Unfortunately, exogenous administration of these neurotrophins is limited by a lack of blood-brain-barrier (BBB) permeability, poor half-life, and rapid degradation. Therefore, we have focused this review on approaches that provide a direct and sustained neurotrophic support using pharmacological therapies and mimetics, physical activity, and potential drug delivery systems, including discussion around advantages and limitations for use of each of these systems. Finally, we discuss future directions of biomaterial drug-delivery systems, including the incorporation of heparan sulfate (HS) in conjunction with neurotrophin-based interventions.
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Affiliation(s)
- Josh Houlton
- Brain Health Research Centre, Department of Anatomy, University of Otago, Dunedin, New Zealand
| | - Nashat Abumaria
- State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Institute of Brain Science, Fudan University, Shanghai, China
- Department of Laboratory Animal Science, Shanghai Medical College, Fudan University, Shanghai, China
| | - Simon F. R. Hinkley
- The Ferrier Research Institute, Victoria University of Wellington, Petone, New Zealand
| | - Andrew N. Clarkson
- Brain Health Research Centre, Department of Anatomy, University of Otago, Dunedin, New Zealand
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12
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Ahmadian N, Mahmoudi J, Talebi M, Molavi L, Sadigh-Eteghad S, Rostrup E, Ziaee M. Sleep deprivation disrupts striatal anti-apoptotic responses in 6-hydroxy dopamine-lesioned parkinsonian rats. IRANIAN JOURNAL OF BASIC MEDICAL SCIENCES 2019; 21:1289-1296. [PMID: 30627374 PMCID: PMC6312672 DOI: 10.22038/ijbms.2018.28546.6919] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Objective(s): The present study was conducted to examine the effect of sleep deprivation (SD) on the anti-apoptotic pathways in Parkinsonian rats. Materials and Methods: Male Wistar rats (n = 40) were assigned to four groups (10 animals each): sham surgery (Sham), 6-hydroxydopamine (6-OHDA)-lesioned (OH), 6-OHDA-lesioned plus grid control (OH+GC), 6-OHDA-lesioned plus SD (OH+SD). Parkinson’s disease (PD) model was induced by the unilateral intra-striatal infusion of 6-OHDA (10 µg/rat). SD (4 hr/day, for 14 days) was induced using a multiple platforms water tank. On the last day of interventions, animals were subjected to open field test for horizontal motor performance assessment. Also, brain-derived neurotrophic factor (BDNF), Bcl-2 and Bax were assessed in the striatum of study groups. Results: SD obscured the motor deficits of PD animals observed in open field test. BDNF level and Bcl2/Bax ratio significantly increased in the OH group, and SD reduced their levels in the PD animals. Conclusion: SD suppressed the anti-apoptotic compensatory responses in the striatum; therefore, it may accelerate continual neuronal cell death in PD.
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Affiliation(s)
- Nahid Ahmadian
- Neurosciences Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Molecular Medicine, Faculty of Advanced Biomedical Sciences, Tabriz, Iran
| | - Javad Mahmoudi
- Neurosciences Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mahnaz Talebi
- Neurosciences Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Leila Molavi
- Pharmaceutical Biotechnology Department, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Saeed Sadigh-Eteghad
- Neurosciences Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Egill Rostrup
- Mental Health Centre Glostrup, University of Copenhagen, Glostrup, Denmark
| | - Mojtaba Ziaee
- Cardiovascular Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
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13
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Lejri I, Grimm A, Eckert A. Mitochondria, Estrogen and Female Brain Aging. Front Aging Neurosci 2018; 10:124. [PMID: 29755342 PMCID: PMC5934418 DOI: 10.3389/fnagi.2018.00124] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 04/11/2018] [Indexed: 12/11/2022] Open
Abstract
Mitochondria play an essential role in the generation of steroid hormones including the female sex hormones. These hormones are, in turn, able to modulate mitochondrial activities. Mitochondria possess crucial roles in cell maintenance, survival and well-being, because they are the main source of energy as well as of reactive oxygen species (ROS) within the cell. The impairment of these important organelles is one of the central features of aging. In women’s health, estrogen plays an important role during adulthood not only in the estrous cycle, but also in the brain via neuroprotective, neurotrophic and antioxidant modes of action. The hypestrogenic state in the peri- as well as in the prolonged postmenopause might increase the vulnerability of elderly women to brain degeneration and age-related pathologies. However, the underlying mechanisms that affect these processes are not well elucidated. Understanding the relationship between estrogen and mitochondria might therefore provide better insights into the female aging process. Thus, in this review, we first describe mitochondrial dysfunction in the aging brain. Second, we discuss the estrogen-dependent actions on the mitochondrial activity, including recent evidence of the estrogen—brain-derived neurotrophic factor and estrogen—sirtuin 3 (SIRT3) pathways, as well as their potential implications during female aging.
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Affiliation(s)
- Imane Lejri
- Neurobiology Lab for Brain Aging and Mental Health, Transfaculty Research Platform Molecular and Cognitive Neuroscience, University of Basel, Basel, Switzerland.,Psychiatric University Clinics, University of Basel, Basel, Switzerland
| | - Amandine Grimm
- Neurobiology Lab for Brain Aging and Mental Health, Transfaculty Research Platform Molecular and Cognitive Neuroscience, University of Basel, Basel, Switzerland.,Psychiatric University Clinics, University of Basel, Basel, Switzerland
| | - Anne Eckert
- Neurobiology Lab for Brain Aging and Mental Health, Transfaculty Research Platform Molecular and Cognitive Neuroscience, University of Basel, Basel, Switzerland.,Psychiatric University Clinics, University of Basel, Basel, Switzerland
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14
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Yue P, Gao L, Wang X, Ding X, Teng J. Ultrasound‐triggered effects of the microbubbles coupled to GDNF‐ and Nurr1‐loaded PEGylated liposomes in a rat model of Parkinson's disease. J Cell Biochem 2018; 119:4581-4591. [DOI: 10.1002/jcb.26608] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Accepted: 12/07/2017] [Indexed: 12/23/2022]
Affiliation(s)
- Peijian Yue
- Department of NeurologyThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Lin Gao
- Department of Neurological Intensive Care UnitThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Xuejing Wang
- Department of NeurologyThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Xuebing Ding
- Department of NeurologyThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Junfang Teng
- Department of NeurologyThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
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15
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Zaman V, Li Z, Middaugh L, Ramamoorthy S, Rohrer B, Nelson ME, Tomac AC, Hoffer BJ, Gerhardt GA, Granholm AC. The Noradrenergic System of Aged GDNF Heterozygous Mice. Cell Transplant 2017; 12:291-303. [DOI: 10.3727/000000003108746740] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Glial cell line-derived neurotrophic factor (GDNF) is a trophic factor for noradrenergic (NE) neurons of the pontine nucleus locus coeruleus (LC). Decreased function of the LC-NE neurons has been found during normal aging and in neurodegenerative disorders. We have previously shown that GDNF participates in the differentiation of LC-NE neurons during development. However, the continued role of GDNF for LC-NE neurons during maturation and aging has not been addressed. We examined alterations in aged mice that were heterozygous for the GDNF gene (Gdnf+/–). Wild-type (Gdnf+/+) and Gdnf+/– mice (18 months old) were tested for locomotor activity and brain tissues were collected for measuring norepinephrine levels and uptake, as well as for morphological analysis. Spontaneous locomotion was reduced in Gdnf+/– mice in comparison with Gdnf+/+ mice. The reduced locomotor activity of Gdnf +/– mice was accompanied by reductions in NE transporter activity in the cerebellum and brain stem as well as decreased norepinephrine tissue levels in the LC. Tyrosine hydroxylase (TH) immunostaining demonstrated morphological alterations of LC-NE cell bodies and abnormal TH-positive fibers in the hippocampus, cerebellum, and frontal cortex of Gdnf+/– mice. These findings suggest that the LC-NE system of Gdnf+/– mice is impaired and suggest that GDNF plays an important role in continued maintenance of this neuronal system throughout life.
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Affiliation(s)
- V. Zaman
- Department of Physiology and Neuroscience and the Center on Aging, Medical University of South Carolina, Charleston, SC 29425
| | - Z. Li
- Department of Neurology, Medical University of South Carolina, Charleston, SC 29425
| | - L. Middaugh
- Department of Psychiatry, Medical University of South Carolina, Charleston, SC 29425
| | - S. Ramamoorthy
- Department of Physiology and Neuroscience and the Center on Aging, Medical University of South Carolina, Charleston, SC 29425
| | - B. Rohrer
- Department of Physiology and Neuroscience and the Center on Aging, Medical University of South Carolina, Charleston, SC 29425
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC 29425
| | - M. E. Nelson
- Department of Physiology and Neuroscience and the Center on Aging, Medical University of South Carolina, Charleston, SC 29425
| | - A. C. Tomac
- National Institute on Drug Abuse, IRP, Baltimore, MD 21224
| | - B. J. Hoffer
- National Institute on Drug Abuse, IRP, Baltimore, MD 21224
| | - G. A. Gerhardt
- Chandler Medical Center, Department of Anatomy & Neurobiology, University of Kentucky, Lexington, KY 40536-0098
| | - A. Ch. Granholm
- Department of Physiology and Neuroscience and the Center on Aging, Medical University of South Carolina, Charleston, SC 29425
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16
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Cass WA, Peters LE. Reduced ability of calcitriol to promote augmented dopamine release in the lesioned striatum of aged rats. Neurochem Int 2017; 108:222-229. [PMID: 28390950 DOI: 10.1016/j.neuint.2017.04.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Revised: 03/13/2017] [Accepted: 04/03/2017] [Indexed: 11/18/2022]
Abstract
Parkinson's disease (PD) is a progressive and debilitating neurodegenerative disorder that affects over one million people in the United States. Previous studies, carried out in young adult rats, have shown that calcitriol, the active metabolite of vitamin D, can be neuroprotective in 6-hydroxydopamine (6-OHDA) models of PD. However, as PD usually affects older individuals, the ability of calcitriol to promote dopaminergic recovery was examined in lesioned young adult (4 month old), middle-aged (14 month old) and aged (22 month old) rats. Animals were given a single injection of 12 μg 6-OHDA into the right striatum. Four weeks later they were administered vehicle or calcitriol (1.0 μg/kg, s.c.) once a day for eight consecutive days. In vivo microdialysis experiments were carried out three weeks after the calcitriol or vehicle treatments to measure potassium and amphetamine evoked overflow of DA from both the left and right striata. In control animals treated with 6-OHDA and vehicle there were significant reductions in evoked overflow of DA on the lesioned side of the brain compared to the contralateral side. The calcitriol treatments significantly increased evoked overflow of DA from the lesioned striatum in both the young adult and middle-aged rats. However, the calcitriol treatments did not significantly augment DA overflow in the aged rats. Postmortem tissue levels of striatal DA were also increased in the young and middle-aged animals, but not in the aged animals. In the substantia nigra, the calcitriol treatments led to increased levels of DA in all three age groups. Thus, the effects of calcitriol were similar in the young adult and middle-aged animals, but in the aged animals the effects of calcitriol were diminished. These results suggest that calcitriol may help promote recovery of dopaminergic functioning in injured nigrostriatal neurons; however, the effectiveness of calcitriol may be reduced in aging.
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Affiliation(s)
- Wayne A Cass
- Department of Anatomy and Neurobiology, University of Kentucky College of Medicine, Lexington, KY, USA.
| | - Laura E Peters
- Department of Anatomy and Neurobiology, University of Kentucky College of Medicine, Lexington, KY, USA
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17
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Mercado NM, Collier TJ, Freeman T, Steece-Collier K. Repairing the Aged Parkinsonian Striatum: Lessons from the Lab and Clinic. JOURNAL OF CLINICAL & CELLULAR IMMUNOLOGY 2016; 7:476. [PMID: 28111608 PMCID: PMC5243125 DOI: 10.4172/2155-9899.1000476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The primary risk factor associated with Parkinson's disease (PD) is advanced age. While there are symptomatic therapies for PD, efficacy of these eventually wane and/or side-effects develop over time. An alternative experimental therapy that has received a great deal of attention over the past several decades has been neural transplantation aimed at replacing nigral dopamine (DA) neurons that degenerate in PD. However, in PD patients and parkinsonian rats, advanced age is associated with inferior benefit following intrastriatal grafting of embryonic DA neurons. Traditionally it has been thought that decreased therapeutic benefit results from the decreased survival of grafted DA neurons and the accompanying poor reinnervation observed in the aged host. However, recent clinical and preclinical data suggest that factors inherent to the aged striatum per se limit successful brain repair. In this short communication, we focus discussion on the implications of our recent grafting study in aged parkinsonian rats, with additional emphasis on a recent clinical report of the outcome of cell therapy in an aged PD patient with long-term (24 years) survival of DA neuron grafts. To address aging as a limiting factor in successful brain repair, we use the example of cell transplantation as a means to interrogate the environment of the aged striatum and identify factors that may, or may not, respond to interventions aimed at improving the prospects for adequate repair of the aged brain. We offer discussion of how these recent reports, in the context of other historical grafting studies, might provide new insight into specific risk factors that have potential to negatively impact all DA cell or terminal replacement strategies for clinical use in PD.
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Affiliation(s)
- Natosha M Mercado
- Department of Translational Science & Molecular Medicine, College of Human Medicine, Michigan State University, Grand Rapids, MI 49503, USA
| | - Timothy J Collier
- Department of Translational Science & Molecular Medicine, College of Human Medicine, Michigan State University, Grand Rapids, MI 49503, USA
- Hauenstein Neuroscience Center, Mercy Health Saint Mary’s, Grand Rapids, Michigan 49503, USA
| | - Thomas Freeman
- Department of Neurosurgery and Brain Repair, Center of Excellence for Aging and Brain Repair, College of Medicine, University of South Florida, FL 33612, USA
| | - Kathy Steece-Collier
- Department of Translational Science & Molecular Medicine, College of Human Medicine, Michigan State University, Grand Rapids, MI 49503, USA
- Hauenstein Neuroscience Center, Mercy Health Saint Mary’s, Grand Rapids, Michigan 49503, USA
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18
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Adly MA, Assaf HA, Hussein MRA. Age-associated decrease in GDNF and its cognate receptor GFRα-1 protein expression in human skin. Int J Exp Pathol 2016; 97:248-56. [PMID: 27346872 DOI: 10.1111/iep.12175] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 01/15/2016] [Indexed: 11/28/2022] Open
Abstract
Glial cell line-derived neurotrophic factor (GDNF) and its cognate receptor (GFRα-1) are expressed in normal human skin. They are involved in murine hair follicle morphogenesis and cycling control. We hypothesize that 'GDNF and GFRα-1 protein expression in human skin undergoes age-associated alterations. To test our hypothesis, the expression of these proteins was examined in human skin specimens obtained from 30 healthy individuals representing three age groups: children (5-18 years), adults (19-60 years) and the elderly (61-81 years). Immunofluorescent and light microscopic immunohistologic analyses were performed using tyramide signal amplification and avidin-biotin complex staining methods respectively. GDNF mRNA expression was examined by RT-PCR analysis. GDNF mRNA and protein as well as GFRα-1 protein expressions were detected in normal human skin. We found significantly reduced epidermal expression of these proteins with ageing. In the epidermis, the expression was strong in the skin of children and declined gradually with ageing, being moderate in adults and weak in the elderly. In children and adults, the expression of both GDNF and GFRα-1 proteins was strongest in the stratum basale and decreased gradually towards the surface layers where it was completely absent in the stratum corneum. In the elderly, GDNF and GFRα-1 protein expression was confined to the stratum basale. In the dermis, both GDNF and GFRα-1 proteins had strong expressions in the fibroblasts, sweat glands, sebaceous glands, hair follicles and blood vessels regardless of the age. Thus there is a decrease in epidermal GDNF and GFRα-1 protein expression in normal human skin with ageing. Our findings suggest that the consequences of this is that GFRα-1-mediated signalling is altered during the ageing process. The clinical and therapeutic ramifications of these observations mandate further investigations.
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Affiliation(s)
- Mohamed A Adly
- Department of Zoology, Faculty of Science, Sohag University, Sohag, Egypt
| | - Hanan A Assaf
- Department of Dermatology and Venereology, Faculty of Medicine, Sohag University, Sohag, Egypt
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19
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Shetty AK, Hattiangady B. Grafted Subventricular Zone Neural Stem Cells Display Robust Engraftment and Similar Differentiation Properties and Form New Neurogenic Niches in the Young and Aged Hippocampus. Stem Cells Transl Med 2016; 5:1204-15. [PMID: 27194744 PMCID: PMC4996439 DOI: 10.5966/sctm.2015-0270] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 04/01/2016] [Indexed: 12/30/2022] Open
Abstract
The engraftment and differentiation of alkaline phosphatase-positive neural stem cells (NSCs) expanded from the postnatal subventricular zone (SVZ), 3 months after grafting into the intact young or aged rat hippocampus, were examined. Both young and aged hippocampi supported robust engraftment and similar differentiation of SVZ-NSC graft-derived cells. As clinical application of neural stem cell (NSC) grafting into the brain would also encompass aged people, critical evaluation of engraftment of NSC graft-derived cells in the aged hippocampus has significance. We examined the engraftment and differentiation of alkaline phosphatase-positive NSCs expanded from the postnatal subventricular zone (SVZ), 3 months after grafting into the intact young or aged rat hippocampus. Graft-derived cells engrafted robustly into both young and aged hippocampi. Although most graft-derived cells pervasively migrated into different hippocampal layers, the graft cores endured and contained graft-derived neurons expressing neuron-specific nuclear antigen (NeuN) and γ-amino butyric acid in both groups. A fraction of migrated graft-derived cells in the neurogenic subgranular zone-granule cell layer also expressed NeuN. Neuronal differentiation was, however, occasionally seen amid graft-derived cells that had migrated into non-neurogenic regions, where substantial fractions differentiated into S-100β+ astrocytes, NG2+ oligodendrocyte progenitors, or Olig2+ putative oligodendrocytes. In both age groups, graft cores located in non-neurogenic regions displayed many doublecortin-positive (DCX+) immature neurons at 3 months after grafting. Analyses of cells within graft cores using birth dating and putative NSC markers revealed that DCX+ neurons were newly born neurons derived from engrafted cells and that putative NSCs persisted within the graft cores. Thus, both young and aged hippocampi support robust engraftment and similar differentiation of SVZ-NSC graft-derived cells. Furthermore, some grafted NSCs retain the “stemness” feature and produce new neurons even at 3 months after grafting, implying that grafting of SVZ-NSCs into the young or aged hippocampus leads to establishment of new neurogenic niches in non-neurogenic regions. Significance The results demonstrate that advanced age of the host at the time of grafting has no major adverse effects on engraftment, migration, and differentiation of grafted subventricular zone-neural stem cells (SVZ-NSCs) in the intact hippocampus, as both young and aged hippocampi promoted excellent engraftment, migration, and differentiation of SVZ-NSC graft-derived cells in the present study. Furthermore, SVZ-NSC grafts showed ability for establishing neurogenic niches in non-neurogenic regions, generating new neurons for extended periods after grafting. This phenomenon will be beneficial if these niches can continuously generate new neurons and glia in the grafted hippocampus, as newly generated neurons and glia are expected to improve, not only the microenvironment, but also the plasticity and function of the aged hippocampus. Overall, these results have significance because the potential application of NSC grafting for treatment of neurodegenerative disorders at early stages of disease progression and age-related impairments would mostly involve aged persons as recipients.
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Affiliation(s)
- Ashok K Shetty
- Institute for Regenerative Medicine, Texas A&M Health Science Center College of Medicine at Scott & White, Temple, Texas, USAResearch Service, Olin E. Teague Veterans' Medical Center, Central Texas Veterans Health Care System, Temple, Texas, USADepartment of Molecular and Cellular Medicine, Texas A&M Health Science Center College of Medicine, College Station, Texas, USADivision of Neurosurgery, Duke University Medical Center, Durham, North Carolina, USAResearch and Surgery Services, Durham Veterans Affairs Medical Center, Durham, North Carolina, USA
| | - Bharathi Hattiangady
- Institute for Regenerative Medicine, Texas A&M Health Science Center College of Medicine at Scott & White, Temple, Texas, USAResearch Service, Olin E. Teague Veterans' Medical Center, Central Texas Veterans Health Care System, Temple, Texas, USADepartment of Molecular and Cellular Medicine, Texas A&M Health Science Center College of Medicine, College Station, Texas, USADivision of Neurosurgery, Duke University Medical Center, Durham, North Carolina, USAResearch and Surgery Services, Durham Veterans Affairs Medical Center, Durham, North Carolina, USA
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20
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Ayadi AE, Zigmond MJ, Smith AD. IGF-1 protects dopamine neurons against oxidative stress: association with changes in phosphokinases. Exp Brain Res 2016; 234:1863-1873. [PMID: 26894890 DOI: 10.1007/s00221-016-4572-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Accepted: 01/22/2016] [Indexed: 11/25/2022]
Abstract
Insulin-like growth factor-1 (IGF-1) is an endogenous peptide transported across the blood brain barrier that is protective in several brain injury models, including an acute animal model of Parkinson's disease (PD). Motor deficits in PD are due largely to the progressive loss of nigrostriatal dopaminergic neurons. Thus, we examined the neuroprotective potential of IGF-1 in a progressive model of dopamine deficiency in which 6-hydroxydopamine (6-OHDA) is infused into the striatum. Rats received intrastriatal IGF-1 (5 or 50 µg) 6 h prior to infusion of 4 µg 6-OHDA into the same site and were euthanized 1 or 4 weeks later. Both concentrations of IGF-1 protected tyrosine hydroxylase (TH) immunoreactive terminals in striatum at 4 weeks but not at 1 week, indicating that IGF-induced restoration of the dopaminergic phenotype occurred over several weeks. TH-immunoreactive cell loss was only attenuated with 50 µg IGF-1. We then examined the effect of striatal IGF-1 on the Ras/ERK1/2 and PI3K/Akt pathways to ascertain whether their activation correlated with IGF-1-induced protection. Striatal and nigral levels of phospho-ERK1/2 were maximal 6 h after IGF-1 infusion and, with the exception of an increase in nigral pERK2 at 48 h, returned to basal levels by 7 days. Phospho-Akt (Ser473) was elevated 6-24 h post-IGF-1 infusion in both striatum and substantia nigra concomitant with inhibition of pro-death GSK-3β, a downstream target of Akt. These results suggest that IGF-1 can protect the nigrostriatal pathway in a progressive PD model and that this protection is preceded by activation of key pro-survival signaling cascades.
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Affiliation(s)
- Amina El Ayadi
- Pittsburgh Institute for Neurodegenerative Disease, University of Pittsburgh, 3501 Fifth Avenue, 7026 Biomedical Science Tower 3, Pittsburgh, PA, 15261, USA
- Department of Surgery, University of Texas Medical Branch, Galveston, TX, 77550, USA
| | - Michael J Zigmond
- Pittsburgh Institute for Neurodegenerative Disease, University of Pittsburgh, 3501 Fifth Avenue, 7026 Biomedical Science Tower 3, Pittsburgh, PA, 15261, USA
| | - Amanda D Smith
- Pittsburgh Institute for Neurodegenerative Disease, University of Pittsburgh, 3501 Fifth Avenue, 7026 Biomedical Science Tower 3, Pittsburgh, PA, 15261, USA.
- VA Pittsburgh Healthcare System, University of Pittsburgh, Pittsburgh, PA, USA.
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21
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High-Frequency Stimulation of the Rat Entopeduncular Nucleus Does Not Provide Functional or Morphological Neuroprotection from 6-Hydroxydopamine. PLoS One 2015. [PMID: 26222442 PMCID: PMC4519335 DOI: 10.1371/journal.pone.0133957] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Deep brain stimulation (DBS) is the most common neurosurgical treatment for Parkinson’s disease (PD). Whereas the globus pallidus interna (GPi) has been less commonly targeted than the subthalamic nucleus (STN), a recent clinical trial suggests that GPi DBS may provide better outcomes for patients with psychiatric comorbidities. Several laboratories have demonstrated that DBS of the STN provides neuroprotection of substantia nigra pars compacta (SNpc) dopamine neurons in preclinical neurotoxin models of PD and increases brain-derived neurotrophic factor (BDNF). However, whether DBS of the entopeduncular nucleus (EP), the homologous structure to the GPi in the rat, has similar neuroprotective potential in preclinical models has not been investigated. We investigated the impact of EP DBS on forelimb use asymmetry and SNpc degeneration induced by 6-hydroxydopamine (6-OHDA) and on BDNF levels. EP DBS in male rats received unilateral, intrastriatal 6-OHDA and ACTIVE or INACTIVE stimulation continuously for two weeks. Outcome measures included quantification of contralateral forelimb use, stereological assessment of SNpc neurons and BDNF levels. EP DBS 1) did not ameliorate forelimb impairments induced by 6-OHDA, 2) did not provide neuroprotection for SNpc neurons and 3) did not significantly increase BDNF levels in any of the structures examined. These results are in sharp contrast to the functional improvement, neuroprotection and BDNF-enhancing effects of STN DBS under identical experimental parameters in the rat. The lack of functional response to EP DBS suggests that stimulation of the rat EP may not represent an accurate model of clinical GPi stimulation.
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Parkinson GM, Dayas CV, Smith DW. Age-related gene expression changes in substantia nigra dopamine neurons of the rat. Mech Ageing Dev 2015; 149:41-9. [PMID: 26065381 DOI: 10.1016/j.mad.2015.06.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Revised: 06/01/2015] [Accepted: 06/02/2015] [Indexed: 02/01/2023]
Abstract
Ageing affects most, if not all, functional systems in the body. For example, the somatic motor nervous system, responsible for initiating and regulating motor output to skeletal musculature, is vulnerable to ageing. The nigrostriatal dopamine pathway is one component of this system, with deficits in dopamine signalling contributing to major motor dysfunction, as exemplified in Parkinson's disease (PD). However, while the dopamine deficit in PD is due to degeneration of substantia nigra (SN) dopamine (DA) neurons, it is unclear whether there is sufficient loss of SN DA neurons with ageing to explain observed motor impairments. Instead, evidence suggests that age-related loss of DA neuron function may be more important than frank cell loss. To further elucidate the mechanisms of functional decline, we have investigated age-related changes in gene expression specifically in laser microdissected SN DA neurons. There were significant age-related changes in the expression of genes associated with neurotrophic factor signalling and the regulation of tyrosine hydroxylase activity. Furthermore, reduced expression of the DA neuron-associated transcription factor, Nurr1, may contribute to these changes. Together, these results suggest that altered neurotrophic signalling and tyrosine hydroxylase activity may contribute to altered DA neuron signalling and motor nervous system regulation in ageing.
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Affiliation(s)
- Gemma M Parkinson
- Preclinical Neurobiology Research Program, School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, NSW 2308, Australia; Centre for Translational Neuroscience and Mental Health Research, University of Newcastle, Callaghan, NSW 2308, Australia; Hunter Medical Research Institute, 1/Kookaburra Circuit, New Lambton Heights, NSW 2305, Australia.
| | - Christopher V Dayas
- Preclinical Neurobiology Research Program, School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, NSW 2308, Australia; Centre for Translational Neuroscience and Mental Health Research, University of Newcastle, Callaghan, NSW 2308, Australia; Hunter Medical Research Institute, 1/Kookaburra Circuit, New Lambton Heights, NSW 2305, Australia.
| | - Doug W Smith
- Preclinical Neurobiology Research Program, School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, NSW 2308, Australia; Centre for Translational Neuroscience and Mental Health Research, University of Newcastle, Callaghan, NSW 2308, Australia; Hunter Medical Research Institute, 1/Kookaburra Circuit, New Lambton Heights, NSW 2305, Australia.
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Paumier KL, Sortwell CE, Madhavan L, Terpstra B, Daley BF, Collier TJ. Tricyclic antidepressant treatment evokes regional changes in neurotrophic factors over time within the intact and degenerating nigrostriatal system. Exp Neurol 2015; 266:11-21. [PMID: 25681575 DOI: 10.1016/j.expneurol.2015.02.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Revised: 01/07/2015] [Accepted: 02/04/2015] [Indexed: 01/16/2023]
Abstract
In addition to alleviating depression, trophic responses produced by antidepressants may regulate neural plasticity in the diseased brain, which not only provides symptomatic benefit but also potentially slows the rate of disease progression in Parkinson's disease (PD). Recent in vitro and in vivo data provide evidence that neurotrophic factors such as brain-derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF) may be key mediators of the therapeutic response to antidepressants. As such, we conducted a cross-sectional time-course study to determine whether antidepressant-mediated changes in neurotrophic factors occur in relevant brain regions in response to amitriptyline (AMI) treatment before and after intrastriatal 6-hydroxydopamine (6OHDA). Adult male Wistar rats were divided into seven cohorts and given daily injections (i.p.) of AMI (5mg/kg) or saline throughout the duration of the study. In parallel, various cohorts of intact or parkinsonian animals were sacrificed at specific time points to determine the impact of AMI treatment on trophic factor levels in the intact and degenerating nigrostriatal system. The left and right hemispheres of the substantia nigra, striatum, frontal cortex, piriform cortex, hippocampus, and anterior cingulate cortex were dissected, and BDNF and GDNF levels were measured with ELISA. Results show that chronic AMI treatment elicits effects in multiple brain regions and differentially regulates levels of BDNF and GDNF depending on the region. Additionally, AMI halts the progressive degeneration of dopamine (DA) neurons elicited by an intrastriatal 6-OHDA lesion. Taken together, these results suggest that AMI treatment elicits significant trophic changes important to DA neuron survival within both the intact and degenerating nigrostriatal system.
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Affiliation(s)
- Katrina L Paumier
- Department of Translational Science and Molecular Medicine, Michigan State University, Grand Rapids, MI, USA.
| | - Caryl E Sortwell
- Department of Translational Science and Molecular Medicine, Michigan State University, Grand Rapids, MI, USA
| | | | - Brian Terpstra
- The Parkinson's Disease Rehabilitation Institute, Cincinnati, OH, USA
| | - Brian F Daley
- Department of Translational Science and Molecular Medicine, Michigan State University, Grand Rapids, MI, USA
| | - Timothy J Collier
- Department of Translational Science and Molecular Medicine, Michigan State University, Grand Rapids, MI, USA
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Yurek DM, Hasselrot U, Cass WA, Sesenoglu-Laird O, Padegimas L, Cooper MJ. Age and lesion-induced increases of GDNF transgene expression in brain following intracerebral injections of DNA nanoparticles. Neuroscience 2014; 284:500-512. [PMID: 25453772 DOI: 10.1016/j.neuroscience.2014.10.026] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Revised: 10/10/2014] [Accepted: 10/14/2014] [Indexed: 01/30/2023]
Abstract
In previous studies that used compacted DNA nanoparticles (DNP) to transfect cells in the brain, we observed higher transgene expression in the denervated striatum when compared to transgene expression in the intact striatum. We also observed that long-term transgene expression occurred in astrocytes as well as neurons. Based on these findings, we hypothesized that the higher transgene expression observed in the denervated striatum may be a function of increased gliosis. Several aging studies have also reported an increase of gliosis as a function of normal aging. In this study we used DNPs that encoded for human glial cell line-derived neurotrophic factor (hGDNF) and either a non-specific human polyubiquitin C (UbC) or an astrocyte-specific human glial fibrillary acidic protein (GFAP) promoter. The DNPs were injected intracerebrally into the denervated or intact striatum of young, middle-aged or aged rats, and glial cell line-derived neurotrophic factor (GDNF) transgene expression was subsequently quantified in brain tissue samples. The results of our studies confirmed our earlier finding that transgene expression was higher in the denervated striatum when compared to intact striatum for DNPs incorporating either promoter. In addition, we observed significantly higher transgene expression in the denervated striatum of old rats when compared to young rats following injections of both types of DNPs. Stereological analysis of GFAP+ cells in the striatum confirmed an increase of GFAP+ cells in the denervated striatum when compared to the intact striatum and also an age-related increase; importantly, increases in GFAP+ cells closely matched the increases in GDNF transgene levels. Thus neurodegeneration and aging may lay a foundation that is actually beneficial for this particular type of gene therapy while other gene therapy techniques that target neurons are actually targeting cells that are decreasing as the disease progresses.
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Affiliation(s)
- D M Yurek
- Department of Neurosurgery, University of Kentucky College of Medicine, Lexington, KY 40536, United States.
| | - U Hasselrot
- Department of Neurosurgery, University of Kentucky College of Medicine, Lexington, KY 40536, United States
| | - W A Cass
- Department of Anatomy & Neurobiology, University of Kentucky College of Medicine, Lexington, KY 40536, United States
| | | | - L Padegimas
- Copernicus Therapeutics, Inc., Cleveland, OH 44106, United States
| | - M J Cooper
- Copernicus Therapeutics, Inc., Cleveland, OH 44106, United States
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25
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Fonseca CP, Gama S, Saavedra A, Baltazar G. H2O2- or l-DOPA-injured dopaminergic neurons trigger the release of soluble mediators that up-regulate striatal GDNF through different signalling pathways. Biochim Biophys Acta Mol Basis Dis 2014; 1842:927-34. [DOI: 10.1016/j.bbadis.2014.03.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Revised: 02/21/2014] [Accepted: 03/04/2014] [Indexed: 11/26/2022]
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26
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Cass WA, Peters LE, Fletcher AM, Yurek DM. Calcitriol promotes augmented dopamine release in the lesioned striatum of 6-hydroxydopamine treated rats. Neurochem Res 2014; 39:1467-76. [PMID: 24858239 DOI: 10.1007/s11064-014-1331-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Revised: 05/06/2014] [Accepted: 05/09/2014] [Indexed: 10/25/2022]
Abstract
Current therapies for Parkinson's disease (PD) offer symptomatic relief but do not provide a cure or slow the disease process. Treatments that could halt progression of the disease or help restore function to damaged neurons would be of substantial benefit. Calcitriol, the active metabolite of vitamin D, has been shown to have significant effects on the brain. These effects include upregulating trophic factor levels, and reducing the severity of some central nervous system lesions. While previous studies have shown that calcitriol can be neuroprotective in 6-hydroxydopamine (6-OHDA) rodent models of PD, the present experiments were designed to examine the ability of calcitriol to promote restoration of extracellular dopamine (DA) levels and tissue content of DA in animals previously lesioned with 6-OHDA. Male Fischer-344 rats were given a single injection of 12 µg 6-OHDA into the right striatum. Four weeks later the animals were administered vehicle or calcitriol (0.3 or 1.0 µg/kg, s.c.) once a day for eight consecutive days. Three weeks after the calcitriol treatments in vivo microdialysis experiments were conducted to measure potassium and amphetamine evoked overflow of DA from both the left and right striata. In control animals treated with 6-OHDA and vehicle there were significant reductions in both potassium and amphetamine evoked overflow of DA on the lesioned side of the brain compared to the contralateral side. In animals treated with 6-OHDA followed by calcitriol there was significantly greater potassium and amphetamine evoked overflow of DA from the lesioned striatum compared to that from the control animals. The calcitriol treatments also led to increases in postmortem tissue levels of DA in the striatum and substantia nigra. These results suggest that calcitriol may help promote recovery of dopaminergic functioning in injured nigrostriatal neurons.
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Affiliation(s)
- Wayne A Cass
- Department of Anatomy and Neurobiology, MN-225 Chandler Medical Center, University of Kentucky College of Medicine, Lexington, KY, 40536-0298, USA,
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27
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O’Neill MJ, Siemers ER. Pharmacological approaches to disease-modifying therapies in Parkinson’s disease. Expert Rev Neurother 2014; 2:819-34. [DOI: 10.1586/14737175.2.6.819] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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28
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6-Hydroxydopamine induces distinct alterations in GDF5 and GDNF mRNA expression in the rat nigrostriatal system in vivo. Neurosci Lett 2013; 561:176-81. [PMID: 24373993 DOI: 10.1016/j.neulet.2013.12.046] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Revised: 12/05/2013] [Accepted: 12/20/2013] [Indexed: 01/07/2023]
Abstract
Growth/differentiation factor (GDF)5 and glial cell line-derived neurotrophic factor (GDNF) are neurotrophic factors that promote the survival of midbrain dopaminergic neurons in vitro and in vivo. Both factors have potent neurotrophic and neuroprotective effects in rat models of Parkinson's disease (PD) and represent promising new therapies for PD. The aim of this study was to investigate the expression of GDF5, GDNF and their receptors in the nigrostriatal dopaminergic system in rat models of PD. It found that endogenous GDF5, GDNF and their receptors are differentially expressed in two 6-hydroxydopamine lesion models of PD. In both striatal and medial forebrain bundle (MFB) lesion models, striatal levels of GDF5 mRNA increased at 10 days post-lesion, while GDNF mRNA levels in the nigrostriatal system decreased after 10 and 28 days. Midbrain mRNA levels for both GDF5 receptors transiently increased after striatal lesion, whereas those of two GDNF receptors decreased at later time-points in both models. Despite the fact that exogenous GDF5 and GDNF have comparable effects on dopaminergic neurons in vitro and in vivo, their endogenous responses to neurotoxic injury are different. This highlights the importance of studying neurotrophic factor expression at distinct disease stages and in various animal models of PD.
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29
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Parmar MS, Jaumotte JD, Wyrostek SL, Zigmond MJ, Cavanaugh JE. Role of ERK1, 2, and 5 in dopamine neuron survival during aging. Neurobiol Aging 2013; 35:669-79. [PMID: 24411019 DOI: 10.1016/j.neurobiolaging.2013.09.031] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Revised: 07/15/2013] [Accepted: 09/19/2013] [Indexed: 11/27/2022]
Abstract
Extracellular signal-regulated kinases (ERKs) 1, 2, and 5 have been shown to play distinct roles in proliferation, differentiation, and neuronal viability. In this study, we examined ERK1, 2, and 5 expression and activation in the substantia nigra (SN), striatum (STR), and ventral tegmental area (VTA) during aging. An age-related decrease in phosphorylated ERK5 was observed in the SN and STR, whereas an increase in total ERK1 was observed in all 3 regions. In primary cultures of the SN and VTA, inhibition of ERK5 but not ERK1 and 2 decreased dopamine neuronal viability significantly. These data suggest that ERK5 is essential for the basal survival of SN and VTA dopaminergic neurons. This is the first study to examine ERK1, 2, and 5 expression and activation in the SN, STR, and VTA during aging, and the relative roles of ERK1, 2, and 5 in basal survival of SN and VTA dopaminergic neurons. These data raise the possibility that a decline in ERK5 signaling may play a role in age-related impairments in dopaminergic function.
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Affiliation(s)
- Mayur S Parmar
- Division of Pharmaceutical Sciences, Mylan School of Pharmacy, Duquesne University, Pittsburgh, PA, USA
| | - Juliann D Jaumotte
- Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, PA, USA
| | - Stephanie L Wyrostek
- Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, PA, USA
| | - Michael J Zigmond
- Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, PA, USA
| | - Jane E Cavanaugh
- Division of Pharmaceutical Sciences, Mylan School of Pharmacy, Duquesne University, Pittsburgh, PA, USA.
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30
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Geraniol ameliorates the motor behavior and neurotrophic factors inadequacy in MPTP-induced mice model of Parkinson's disease. J Mol Neurosci 2013; 51:851-62. [PMID: 23943375 PMCID: PMC3824202 DOI: 10.1007/s12031-013-0074-9] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2013] [Accepted: 07/11/2013] [Indexed: 11/01/2022]
Abstract
Many experiments affirm the notion that augmentation of neurotrophic factors (NTFs) activity, especially brain-derived neurotrophic factors and glial cell-derived neurotrophic factors, could prevent or halt the progress of neurodegeneration in Parkinson's disease (PD). In this study, we investigated the therapeutic accomplishment of geraniol (GE 100 mg/kg) on 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced mice model of PD. Current investigation proved that pretreatment with GE ameliorates the MPTP-induced alterations in behavioral, biochemical, immunohistochemical, and immunoblotting manifestations in mice. Systematically, the loss of dopaminergic neurons and reduced NTFs mRNA expressions induced by MPTP was ameliorated to a significant extent by pretreatment with GE. We found that GE confers a potent neuroprotective agent against MPTP-induced dopaminergic denervation and may become a potential therapeutic agent for PD and/or its progression.
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31
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The proform of glia cell line-derived neurotrophic factor: a potentially biologically active protein. Mol Neurobiol 2013; 49:234-50. [PMID: 23934644 DOI: 10.1007/s12035-013-8515-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Accepted: 07/10/2013] [Indexed: 12/24/2022]
Abstract
Growing evidences have revealed that the proforms of several neurotrophins including nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and neurotrophin-3 (NT3), by binding to p75 neurotrophin receptor and sortilin, could induce neuronal apoptosis and are implicated in the pathogenesis of various neurodegenerative diseases. The glial cell line-derived neurotrophic factor (GDNF), one of the most potent useful neurotrophic factors for the treatment of Parkinson's disease (PD), is firstly synthesized as the proform (proGDNF) like other neurotrophin NGF, BDNF, and NT3. However, little is known about proGDNF expression and secretion under physiological as well as pathological states in vivo or in vitro. In this study, we investigated the expression profile and dynamic changes of proGDNF in brains of aging and PD animal models, with the interesting finding that proGDNF was a predominant form of GDNF with molecular weight of about 36 kDa by reducing and nonreducing immunoblots in adult brains and was unregulated in the aging, lipopolysaccharide (LPS), and 1-methyl-4-phenyl- 1,2,3,6-tetrahydropyridine (MPTP) insult. We further provided direct evidence that accompanied activation of primary astrocytes as well as C6 cell line induced by LPS stimulation, proGDNF was increasingly synthesized and released as the uncleaved form in cell culture. Taken together, our results strongly suggest that proGDNF may be a biologically active protein and has specific effects on the cells close to its secreting site, and a potentially important role of proGDNF signaling in the brains, in the glia-neuronal interaction or in the pathogenesis of PD, should merit further investigation.
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Yang S, Sun HM, Yan JH, Xue H, Wu B, Dong F, Li WS, Ji FQ, Zhou DS. Conditioned medium from human amniotic epithelial cells may induce the differentiation of human umbilical cord blood mesenchymal stem cells into dopaminergic neuron-like cells. J Neurosci Res 2013; 91:978-86. [PMID: 23633297 DOI: 10.1002/jnr.23225] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Revised: 02/05/2013] [Accepted: 02/25/2013] [Indexed: 11/07/2022]
Abstract
Dopaminergic (DA) neuron therapy has been established as a new clinical tool for treating Parkinson's disease (PD). Prior to cell transplantation, there are two primary issues that must be resolved: one is the appropriate seed cell origin, and the other is the efficient inducing technique. In the present study, human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) were used as the available seed cells, and conditioned medium from human amniotic epithelial cells (ACM) was used as the inducing reagent. Results showed that the proportion of DA neuron-like cells from hUCB-MSCs was significantly increased after cultured in ACM, suggested by the upregulation of DAT, TH, Nurr1, and Pitx3. To identify the process by which ACM induces DA neuron differentiation, we pretreated hUCB-MSCs with k252a, the Trk receptor inhibitor of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF), and found that the proportion of DA neuron-like cells was significantly decreased compared with ACM-treated hUCB-MSCs, suggesting that NGF and BDNF in ACM were involved in the differentiation process. However, we could not rule out the involvement of other unidentified factors in the ACM, because ACM + k252a treatment does not fully block DA neuron-like cell differentiation compared with control. The transplantation of ACM-induced hUCB-MSCs could ameliorate behavioral deficits in PD rats, which may be associated with the survival of engrafted DA neuron-like cells. In conclusion, we propose that hUCB-MSCs are a good source of DA neuron-like cells and that ACM is a potential inducer to obtain DA neuron-like cells from hUCB-MSCs in vitro for an ethical and legal cell therapy for PD.
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MESH Headings
- Amnion/cytology
- Analysis of Variance
- Animals
- Apomorphine
- Brain-Derived Neurotrophic Factor/pharmacology
- Cell Differentiation/drug effects
- Culture Media, Conditioned/pharmacology
- Disease Models, Animal
- Dopamine Plasma Membrane Transport Proteins/genetics
- Dopamine Plasma Membrane Transport Proteins/metabolism
- Dopaminergic Neurons/drug effects
- Enzyme-Linked Immunosorbent Assay
- Epithelial Cells/chemistry
- Fetal Blood/cytology
- Fetus
- Flow Cytometry
- Homeodomain Proteins/genetics
- Homeodomain Proteins/metabolism
- Humans
- Mesenchymal Stem Cell Transplantation/methods
- Mesenchymal Stem Cells/drug effects
- Nuclear Receptor Subfamily 4, Group A, Member 2/genetics
- Nuclear Receptor Subfamily 4, Group A, Member 2/metabolism
- Oxidopamine/toxicity
- Parkinson Disease/etiology
- Parkinson Disease/physiopathology
- Parkinson Disease/surgery
- RNA, Messenger/metabolism
- Rats
- Rats, Sprague-Dawley
- Receptor, trkA/genetics
- Receptor, trkA/metabolism
- Receptor, trkB/metabolism
- Stereotyped Behavior/drug effects
- Stereotyped Behavior/physiology
- Transcription Factors/genetics
- Transcription Factors/metabolism
- Tyrosine 3-Monooxygenase/genetics
- Tyrosine 3-Monooxygenase/metabolism
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Affiliation(s)
- Shu Yang
- Department of Histology and Embryology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
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Littrell OM, Granholm AC, Gerhardt GA, Boger HA. Glial cell-line derived neurotrophic factor (GDNF) replacement attenuates motor impairments and nigrostriatal dopamine deficits in 12-month-old mice with a partial deletion of GDNF. Pharmacol Biochem Behav 2013; 104:10-9. [PMID: 23290934 DOI: 10.1016/j.pbb.2012.12.022] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Revised: 12/05/2012] [Accepted: 12/22/2012] [Indexed: 12/17/2022]
Abstract
Glial cell-line derived neurotrophic factor (GDNF) has been established as a growth factor for the survival and maintenance of dopamine (DA) neurons. In phase I clinical trials, GDNF treatment in Parkinson's disease patients led to improved motor function and GDNF has been found to be down regulated in Parkinson's disease patients. Studies using GDNF heterozygous (Gdnf(+/-)) mice have demonstrated that a partial reduction of GDNF leads to an age-related accelerated decline in nigrostriatal DA system- and motor-function and increased neuro-inflammation and oxidative stress in the substantia nigra (SN). Therefore, the purpose of the current studies was to determine if GDNF replacement restores motor function and functional markers within the nigrostriatal DA system in middle-aged Gdnf(+/-) mice. At 11months of age, male Gdnf(+/-) and wildtype (WT) mice underwent bilateral intra-striatal injections of GDNF (10μg) or vehicle. Locomotor activity was assessed weekly 1-4weeks after treatment. Four weeks after treatment, their brains were processed for analysis of GDNF levels and various DAergic and oxidative stress markers. An intrastriatal injection of GDNF increased motor activity in Gdnf(+/-) mice to levels comparable to WT mice (1week after injection) and this effect was maintained through the 4-week time point. This increase in locomotion was accompanied by a 40% increase in striatal GDNF protein levels and SN GDNF expression in Gdnf(+/-) mice. Additionally, GDNF treatment significantly increased the number of tyrosine hydroxylase (TH)-positive neurons in the SN of middle-aged Gdnf(+/-) mice, but not WT mice, which was coupled with reduced oxidative stress in the SN. These studies further support that long-term changes related to the dysfunction of the nigrostriatal pathway are influenced by GDNF expression and add that this dysfunction appears to be responsive to GDNF treatment. Additionally, these studies suggest that long-term GDNF depletion alters the biological and behavioral responses to GDNF treatment.
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Affiliation(s)
- Ofelia M Littrell
- Department of Anatomy and Neurobiology, Parkinson's Disease Translational Research Center of Excellence, University of Kentucky Medical Center, 306 Davis Mills Bldg., 800 Rose St., Lexington, KY 40536, USA
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Appearance of neural stem cells around the damaged area following traumatic brain injury in aged rats. J Neural Transm (Vienna) 2012; 120:361-74. [PMID: 22955958 DOI: 10.1007/s00702-012-0895-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Accepted: 08/12/2012] [Indexed: 10/27/2022]
Abstract
We have previously reported free radical production after traumatic brain injury (TBI), which induces neural stem cell (NSC) degeneration and death. However, the effects of aging on NSC proliferation around the damaged area following TBI have not been investigated. Therefore, in this study, we used 10-week (young group) and 24-month-old (aged group) rat TBI models to investigate the effects of aging on NSC proliferation around damaged tissue using immunohistochemical and ex vivo techniques. Young and aged rats received TBI. At 1, 3 and 7 days after TBI, immunohistochemical and lipid peroxidation studies were performed. Immunohistochemistry revealed that the number of nestin-positive cells around the damaged area after TBI in the aged group decreased significantly when compared with those in the young group (P < 0.01). However, the number of 8-hydroxy-2'-deoxyguanosine-, 4-hydroxy-2-nonenal- and single-stranded DNA (ssDNA)-positive cells and the level of peroxidation around the damaged area after TBI significantly increased in the aged group, compared with those in the young group (P < 0.01). Furthermore, almost all ssDNA-positive cells in young and aged groups co-localized with NeuN and nestin staining. Ex vivo studies revealed that neurospheres, which differentiated into neurons and glia in culture, could only be isolated from injured brain tissue in young and aged groups at 3 days after TBI. These results indicate that, although there were fewer NSCs that have the potential to differentiate into neurons and glia, these NSCs escaped free radical-induced degeneration around the damaged area after TBI in the aged rat brain.
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Yu M, Suo H, Liu M, Cai L, Liu J, Huang Y, Xu J, Wang Y, Zhu C, Fei J, Huang F. NRSF/REST neuronal deficient mice are more vulnerable to the neurotoxin MPTP. Neurobiol Aging 2012; 34:916-27. [PMID: 22766071 DOI: 10.1016/j.neurobiolaging.2012.06.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2011] [Revised: 05/08/2012] [Accepted: 06/02/2012] [Indexed: 11/30/2022]
Abstract
Parkinson's disease (PD) is characterized by progressing loss of dopaminergic neurons in the midbrain. Abnormal gene expression plays a critical role in its pathogenesis. Neuron-restrictive silencer factor (NRSF)/neuronal repressor element-1 silencing transcription factor (REST), a member of the zinc finger transcription factors, inhibits the expression of neuron-specific genes in nonneuronal cells, and regulates neurogenesis. Our previous work showed that 1-methyl-4-phenyl-pyridinium ion triggers dynamic changes of messenger RNA and protein expression of NRSF in human dopaminergic SH-SY5Y cells, and alteration of NRSF expression exacerbates 1-methyl-4-phenyl-pyridinium ion-induced cell death. The purpose of this study was to explore the in vivo role of NRSF in the progress of PD by using NRSF/REST neuron-specific conditional knockout mice (cKO). 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) was adopted to generate PD models in the cKO mice and wild type littermates. At 1, 3, 7, 14, 21, and 28 days after MPTP injection, behavioral tests were performed, and cKO mice displayed some impairments in locomotor activities. Also, the reduction of tyrosine hydroxylase protein in the striatum and the loss of dopaminergic neurons in the substantia nigra were more severe in the cKO mice. Meanwhile, the cKO mice exhibited a more dramatic depletion of striatal dopamine, accompanied by an increase in glial fibrillary acidic protein (GFAP) expression and sustained interleukin-1β transcription. These results suggested that NRSF/REST neuronal cKO mice are more vulnerable to the dopaminergic neurotoxin MPTP. Disturbance of the homeostasis of NRSF and its target genes, gliogenesis, and inflammation may contribute to the higher MPTP sensitivity in NRSF/REST neuronal cKO mice.
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Affiliation(s)
- Mei Yu
- State Key Laboratory of Medical Neurobiology, Shanghai Medical College, Fudan University, Shanghai, China
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36
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The cortical and striatal gene expression profile of 100 hz electroacupuncture treatment in 6-hydroxydopamine-induced Parkinson's disease model. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2012; 2012:908439. [PMID: 22319547 PMCID: PMC3272844 DOI: 10.1155/2012/908439] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2011] [Revised: 09/05/2011] [Accepted: 09/26/2011] [Indexed: 11/18/2022]
Abstract
Electroacupuncture (EA), especially high-frequency EA, has frequently been used as an alternative therapy for Parkinson disease (PD) and is reportedly effective for alleviating motor symptoms in patients and PD models. However, the molecular mechanism underlying its effectiveness is not completely understood. To implement a full-scale search for the targets of 100 Hz EA, we selected rat models treated with 6-hydroxydopamine into the unilateral MFB, which mimic end-stage PD. High-throughput microarray analysis was then used to uncover the regulated targets in the cortex and striatum after 4-week EA treatment. In the differentially regulated transcripts, the proportion of recovered expression profiles in the genes, the functional categories of targets in different profiles, and the affected pathways were analyzed. Our results suggested that the recovery of homeostasis in the transcript network and many regulated functional clusters in the cortex and striatum after EA treatment may contribute to the behavioral improvement of PD rats.
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37
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Iravani MM, Sadeghian M, Leung CCM, Jenner P, Rose S. Lipopolysaccharide-induced nigral inflammation leads to increased IL-1β tissue content and expression of astrocytic glial cell line-derived neurotrophic factor. Neurosci Lett 2012; 510:138-42. [PMID: 22281445 DOI: 10.1016/j.neulet.2012.01.022] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2011] [Revised: 11/27/2011] [Accepted: 01/08/2012] [Indexed: 10/14/2022]
Abstract
Reactive gliosis and inflammatory change is a key component of nigral dopaminergic cell death in Parkinson's disease (PD). Astrocyte derived glial cell line-derived neurotrophic factor (GDNF) promotes the survival and growth of dopaminergic neurones and it protects against or reverses nigral degeneration induced by 6-OHDA and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in rodents and primates. But the effect of increased levels of pro-inflammatory cytokines on the release of GDNF is unknown. This study examined the relationship between release of tumour necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) and the expression of GDNF in rats following nigral lipopolysaccharide (LPS) administration. Acute nigral administration of LPS led to marked elevation of IL-1β but insignificant TNF-α tissue content and to a prominent expression of GDNF immunoreactivity in astrocytes but not microglia. The results suggest that inflammation is not only involved in neuronal loss but could promote neuronal survival through increased release of GDNF following up-regulation of IL-1β.
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Affiliation(s)
- Mahmoud M Iravani
- Neurodegenerative Disease Research Centre, Institute of Pharmaceutical Sciences, School of Biomedical Sciences, King's College London, SE1 1UL London, UK.
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38
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Survival, differentiation, and connectivity of ventral mesencephalic dopamine neurons following transplantation. PROGRESS IN BRAIN RESEARCH 2012. [DOI: 10.1016/b978-0-444-59575-1.00004-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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39
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Cass WA, Peters LE, Fletcher AM, Yurek DM. Evoked dopamine overflow is augmented in the striatum of calcitriol treated rats. Neurochem Int 2011; 60:186-91. [PMID: 22133428 DOI: 10.1016/j.neuint.2011.11.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Revised: 09/08/2011] [Accepted: 11/15/2011] [Indexed: 11/30/2022]
Abstract
Calcitriol, the active metabolite of vitamin D, has been shown to have significant effects on the brain. These actions include reducing the severity of some central nervous system lesions, possibly by upregulating trophic factors such as glial cell line-derived neurotrophic factor (GDNF). GDNF has substantial effects on the nigrostriatal dopamine (DA) system of young adult, aged and lesioned animals. Thus, the administration of calcitriol may lead to significant effects on nigrostriatal DA neuron functioning. The present experiments were designed to examine the ability of calcitriol to alter striatal DA release, and striatal and nigral tissue levels of DA. Male Fischer-344 rats were administered vehicle or calcitriol (0.3, 1.0, or 3.0 μg/kg, s.c.) once daily for eight consecutive days. Three weeks later in vivo microdialysis experiments were conducted to measure basal and stimulus evoked overflow of DA from the striatum. Basal levels of extracellular DA were not significantly affected by the calcitriol treatments. However, the 1.0 and 3.0 μg/kg doses of calcitriol led to increases in both potassium and amphetamine evoked overflow of striatal DA. Although post-mortem tissue levels of striatal DA were not altered by the calcitriol injections, nigral tissue levels of DA and its main metabolites were increased by both the 1.0 and 3.0 μg/kg doses of calcitriol. In a separate group of animals GDNF levels were augmented in the striatum and substantia nigra after eight consecutive daily injections of calcitriol. These results suggest that systemically administered calcitriol can upregulate dopaminergic release processes in the striatum and DA levels in the substantia nigra. Increases in the levels of endogenous GDNF following calcitriol treatment may in part be responsible for these changes. The ability of calcitriol to lead to augmented DA release in the striatum suggests that calcitriol may be beneficial in disease processes involving dopaminergic dysfunction.
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Affiliation(s)
- Wayne A Cass
- Department of Anatomy and Neurobiology, University of Kentucky, College of Medicine, Lexington, KY 40536-0298, USA.
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40
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Anastasía A, Wojnacki J, de Erausquin GA, Mascó DH. Glial cell-line derived neurotrophic factor is essential for electroconvulsive shock-induced neuroprotection in an animal model of Parkinson's disease. Neuroscience 2011; 195:100-11. [PMID: 21871541 DOI: 10.1016/j.neuroscience.2011.08.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2011] [Revised: 07/18/2011] [Accepted: 08/09/2011] [Indexed: 01/25/2023]
Abstract
Sustained motor improvement in human patients with idiopathic Parkinson's disease has been described following electroconvulsive shock (ECS) treatment. In rats, ECS stimulates the expression of various trophic factors (TFs), some of which have been proposed to exert neuroprotective actions. We previously reported that ECS protects the integrity of the rat nigrostriatal dopaminergic system against 6-hydroxydopamine (6-OHDA)-induced toxicity; in order to shed light into its neuroprotective mechanism, we studied glial cell-line derived neurotrophic factor (GDNF) levels (the most efficient TF for dopaminergic neurons) in the substantia nigra (SN) and striatum of 6-OHDA-injected animals with or without ECS treatment. 6-OHDA injection decreased GDNF levels in the SN control animals, but not in those receiving chronic ECS, suggesting that changes in GDNF expression may participate in the ECS neuroprotective mechanism. To evaluate this possibility, we inhibit GDNF by infusion of GDNF function blocking antibodies in the SN of 6-OHDA-injected animals treated with ECS (or sham ECS). Animals were sacrificed 7 days after 6-OHDA infusion, and the integrity of the nigrostriatal system was studied by tyrosine hydroxylase immunohistochemistry and Cresyl Violet staining. Neuroprotection observed in ECS-treated animals was inhibited by GDNF antibodies in the SN. These results robustly demonstrate that GDNF is essential for the ECS neuroprotective effect observed in 6-OHDA-injected animals.
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Affiliation(s)
- A Anastasía
- Facultad de Ciencias Exactas, Físicas y Naturales, Centro de Biología Celular y Molecular, Universidad Nacional de Córdoba, Av. Vélez Sarsfield 1611, ZC: X5016GCA, Córdoba, Argentina
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41
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Fletcher AM, Kowalczyk TH, Padegimas L, Cooper MJ, Yurek DM. Transgene expression in the striatum following intracerebral injections of DNA nanoparticles encoding for human glial cell line-derived neurotrophic factor. Neuroscience 2011; 194:220-6. [PMID: 21839809 DOI: 10.1016/j.neuroscience.2011.07.072] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Revised: 07/27/2011] [Accepted: 07/29/2011] [Indexed: 11/26/2022]
Abstract
A goal of our studies is to develop a potential therapeutic for Parkinson's disease (PD) by a human glial cell line-derived neurotrophic factor (hGDNF) expression plasmid administered to the rat striatum as a compacted DNA nanoparticle (DNP) and which will generate long-term hGDNF expression at biologically active levels. In the present study, we used a DNA plasmid encoding for hGDNF and a polyubiquitin C (UbC) promoter that was previously shown to have activity in both neurons and glia, but primarily in glia. A two-fold improvement was observed at the highest plasmid dose when using hGDNF DNA incorporating sequences found in RNA splice variant 1 compared with splice variant 2; of note, the splice variant 2 sequence is used in most preclinical studies. This optimized expression cassette design includes flanking scaffold matrix attachment elements (S/MARs) as well as a CpG-depleted prokaryotic domain and, where possible, eukaryotic elements. Stable long-term GDNF activity at levels 300-400% higher than baseline was observed following a single intracerebral injection. In a previous study, DNP plasmids encoding for reporter genes had been successful in generating long-term reporter transgene activity in the striatum (>365 days) and in this study produced sustained GDNF activity at the longest assessed time point (6 months).
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Affiliation(s)
- A M Fletcher
- Department of Neurosurgery, University of Kentucky College of Medicine, Lexington, KY 40536, USA
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42
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Decressac M, Pain S, Chabeauti PY, Frangeul L, Thiriet N, Herzog H, Vergote J, Chalon S, Jaber M, Gaillard A. Neuroprotection by neuropeptide Y in cell and animal models of Parkinson's disease. Neurobiol Aging 2011; 33:2125-37. [PMID: 21816512 DOI: 10.1016/j.neurobiolaging.2011.06.018] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Revised: 06/10/2011] [Accepted: 06/18/2011] [Indexed: 11/26/2022]
Abstract
This study was aimed to investigate the potential neuroprotective effect of neuropeptide Y (NPY) on the survival of dopaminergic cells in both in vitro and in animal models of Parkinson's disease (PD). NPY protected human SH-SY5Y dopaminergic neuroblastoma cells from 6-hydroxydopamine-induced toxicity. In rat and mice models of PD, striatal injection of NPY preserved the nigrostriatal dopamine pathway from degeneration as evidenced by quantification of (1) tyrosine hydroxylase (TH)-positive cells in the substantia nigra pars compacta, levels of (2) striatal tyrosine hydroxylase and dopamine transporter, (3) dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC) as well as (4) rotational behavior. NPY had no neuroprotective effects in mice treated with Y(2) receptor antagonist or in transgenic mice deficient for Y(2) receptor suggesting that NPY effects are mediated through this receptor. Stimulation of Y(2) receptor by NPY triggered the activation of both the ERK1/2 and Akt pathways but did not modify levels of brain derived neurotrophic factor (BDNF) or glial cell line-derived neurotrophic factor. These results open new perspectives in neuroprotective therapies using NPY and suggest potential beneficial effects in PD.
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Affiliation(s)
- Mickael Decressac
- Institut de Physiologie et Biologie Cellulaires, Université de Poitiers, Centre National de la Recherche Scientifique (CNRS), Poitiers, France
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43
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Impact of methamphetamine on dopamine neurons in primates is dependent on age: implications for development of Parkinson's disease. Neuroscience 2011; 189:277-85. [PMID: 21640165 DOI: 10.1016/j.neuroscience.2011.05.046] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2011] [Revised: 04/28/2011] [Accepted: 05/17/2011] [Indexed: 12/13/2022]
Abstract
Methamphetamine is a CNS stimulant with limited therapeutic indications, but is widely abused. Short-term exposure to higher doses, or long-term exposure to lower doses, of methamphetamine induces lasting damage to nigrostriatal dopamine neurons in man and animals. Strong evidence indicates that the mechanism for this detrimental effect on dopamine neurons involves oxidative stress exerted by reactive oxygen species. This study investigates the relative susceptibility of dopamine neurons in mid-gestation, young, and adult (not aged) monkeys to four treatments with methamphetamine over 2 days. Primate dopamine neurons undergo natural cell death at mid-gestation, and we hypothesized that during this event they are particularly vulnerable to oxidative stress. The results indicated that at mid-gestation and in adults, dopamine neurons were susceptible to methamphetamine-induced damage, as indicated by loss of striatal tyrosine hydroxylase (TH) immunoreactivity and dopamine concentration. However, dopamine neurons in young animals appeared totally resistant to the treatment, despite this group having higher brain levels of methamphetamine 3 h after administration than the adults. As a possible explanation for the protection, striatal glial-derived neurotrophic factor (GDNF) levels were elevated in young animals 1 week after treatment, but not in adults following methamphetamine treatment. Implications of these primate studies are: (1) the susceptibility of dopamine neurons at mid-gestation to methamphetamine warns against the risk of exposing pregnant women to the drug or oxidative stressors, and supports the hypothesis of Parkinson's disease being associated with oxidative stress during development, (2) elucidation of the mechanism of resistance of dopamine neurons in the young animals to methamphetamine-induced oxidative stress may provide targets for slowing or preventing age- or disease-related loss of adult nigrostriatal dopamine (DA) neurons, and (3) the increased striatal production of GDNF in young animals, but not in adults, in response to methamphetamine, suggests the possibility of an age-related change in the neurotrophic capacity of the striatal dopamine system.
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44
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Ding YX, Xia Y, Jiao XY, Duan L, Yu J, Wang X, Chen LW. The TrkB-positive dopaminergic neurons are less sensitive to MPTP insult in the substantia nigra of adult C57/BL mice. Neurochem Res 2011; 36:1759-66. [PMID: 21562748 DOI: 10.1007/s11064-011-0491-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/27/2011] [Indexed: 11/24/2022]
Abstract
Tyrosine kinase receptors TrkB and TrkC mediate neuroprotective effects of the brain-derived neurotrophic factor (BDNF) and neurotrophins in the dopaminergic nigro-striatal system, but it is obscure about their responses or expression changes in the injured substantia nigra under Parkinson's disease. In present study, immunofluorescence, Fluoro-Jade staining and laser scanning confocal microscopy were applied to investigate distribution and changes of TrkB and TrkC in the dopamine neurons of the substantia nigra by comparison of control and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model. It revealed that TrkB and TrkC-immunoreactivities were substantially localized in cytoplasm and cell membrane of the substantia nigra neurons of control adults. While neurons double-labeled with tyrosine hydroxylase (TH)/TrkB, or TH/TrkC were distributed in a large numbers in the substantia nigra of controls, they apparently went down at 36.2-65.7% of normal level, respectively following MPTP insult. In MPTP model, cell apoptosis or degeneration of nigral neurons were confirmed by caspase-3 and Fluoro-Jade staining. More interestingly, TH/TrkB-positive neurons survived more in cell numbers in comparison with that of TH/TrkC-positive ones in the MPTP model. This study has indicated that TrkB-containing dopamine neurons are less sensitive in the substantia nigra of MPTP mouse model, suggesting that specific organization of Trks may be involved in neuronal vulnerability to MPTP insult, and BDNF-TrkB signaling may play more important role in protecting dopamine neurons and exhibit therapeutic potential for Parkinson's disease.
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Affiliation(s)
- Yin-Xiu Ding
- Institute of Neurosciences, The Fourth Military Medical University, Xi'an 710032, People's Republic of China
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45
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Littrell OM, Pomerleau F, Huettl P, Surgener S, McGinty JF, Middaugh LD, Granholm AC, Gerhardt GA, Boger HA. Enhanced dopamine transporter activity in middle-aged Gdnf heterozygous mice. Neurobiol Aging 2010; 33:427.e1-14. [PMID: 21144620 DOI: 10.1016/j.neurobiolaging.2010.10.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2010] [Revised: 08/24/2010] [Accepted: 10/16/2010] [Indexed: 01/14/2023]
Abstract
Glial cell line-derived neurotrophic factor (GDNF) supports the viability of midbrain dopamine (DA) neurons that degenerate in Parkinson's disease. Middle-aged, 12 month old, Gdnf heterozygous (Gdnf(+/-)) mice have diminished spontaneous locomotor activity and enhanced synaptosomal DA uptake compared with wild type mice. In this study, dopamine transporter (DAT) function in middle-aged, 12 month old Gdnf(+/-) mice was more thoroughly investigated using in vivo electrochemistry. Gdnf(+/-) mice injected with the DAT inhibitor, nomifensine, exhibited significantly more locomotor activity than wild type mice. In vivo electrochemistry with carbon fiber microelectrodes demonstrated enhanced clearance of DA in the striatum of Gdnf(+/-) mice, suggesting greater surface expression of DAT than in wild type littermates. Additionally, 12 month old Gdnf(+/-) mice expressed greater D(2) receptor mRNA and protein in the striatum than wild type mice. Neurochemical analyses of striatal tissue samples indicated significant reductions in DA and a faster DA metabolic rate in Gdnf(+/-) mice than in wild type mice. Altogether, these data support an important role for GDNF in the regulation of uptake, synthesis, and metabolism of DA during aging.
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Affiliation(s)
- Ofelia M Littrell
- Department of Anatomy and Neurobiology, Morris K. Udall Parkinson's Disease Research, Center of Excellence, University of Kentucky Medical Center, 306 Davis Mills Bldg, 800 Rose St., Lexington, KY 40536, USA
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46
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Boger HA, Mannangatti P, Samuvel DJ, Saylor AJ, Bender TS, McGinty JF, Fortress AM, Zaman V, Huang P, Middaugh LD, Randall PK, Jayanthi LD, Rohrer B, Helke KL, Granholm AC, Ramamoorthy S. Effects of brain-derived neurotrophic factor on dopaminergic function and motor behavior during aging. GENES BRAIN AND BEHAVIOR 2010; 10:186-98. [PMID: 20860702 DOI: 10.1111/j.1601-183x.2010.00654.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Brain-derived neurotrophic factor (BDNF) is critical in synaptic plasticity and in the survival and function of midbrain dopamine neurons. In this study, we assessed the effects of a partial genetic deletion of BDNF on motor function and dopamine (DA) neurotransmitter measures by comparing Bdnf(+/-) with wildtype mice (WT) at different ages. Bdnf(+/-) and WT mice had similar body weights until 12 months of age; however, at 21 months, Bdnf(+/-) mice were significantly heavier than WT mice. Horizontal and vertical motor activity was reduced for Bdnf(+/-) compared to WT mice, but was not influenced by age. Performance on an accelerating rotarod declined with age for both genotypes and was exacerbated for Bdnf(+/-) mice. Body weight did not correlate with any of the three behavioral measures studied. Dopamine neurotransmitter markers indicated no genotypic difference in striatal tyrosine hydroxylase, DA transporter (DAT) or vesicular monoamine transporter 2 (VMAT2) immunoreactivity at any age. However, DA transport via DAT (starting at 12 months) and VMAT2 (starting at 3 months) as well as KCl-stimulated DA release were reduced in Bdnf(+/-) mice and declined with age suggesting an increasingly important role for BDNF in the release and uptake of DA with the aging process. These findings suggest that a BDNF expression deficit becomes more critical to dopaminergic dynamics and related behavioral activities with increasing age.
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Affiliation(s)
- H A Boger
- Department of Neurosciences and the Center on Aging, Medical University of South Carolina, Charleston, SC 29425, USA
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47
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Yurek DM, Fletcher AM, Peters LE, Cass WA. Strain difference in the up-regulation of FGF-2 protein following a neurotoxic lesion of the nigrostriatal pathway. Neurochem Res 2010; 35:531-9. [PMID: 19921430 PMCID: PMC3032212 DOI: 10.1007/s11064-009-0093-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/04/2009] [Indexed: 10/20/2022]
Abstract
Lesions of the nigrostriatal pathway are known to induce a compensatory up-regulation of various neurotrophic factors. In this study we examined protein content of basic fibroblast growth factor (FGF-2) in tissue samples taken from the ventral midbrain and striatum at two different time points following a neurotoxic lesion of the nigrostriatal pathway in two different rat strains, the outbred Sprague-Dawley (SD) and inbred F344 9 Brown Norway F1 hybrid (F344BNF1). Despite both rat strains having comparable lesions of the nigrostriatal pathway, we observed a difference in the temporal up-regulation of FGF-2 in ventral midbrain samples taken from the side ipsilateral to the lesion. Basic FGF was significantly upregulated in ventral midbrain in SD rats 1 week post-lesion while we did not observe an up-regulation of FGF-2 in the lesioned ventral midbrain of F344BNF1 at this same time point. However, both strains showed a significant up-regulation of FGF-2 in the lesioned ventral midbrain 3 weeks post-lesion. Sprague-Dawley rats also appeared to be more sensitive to the lesion in terms of up-regulating FGF-2 expression. The differences reported here suggest currently unknown genetic differences between these two strains may be important factors for regulating the compensatory release of neurotrophic factors, such as FGF-2, in response to a neurotoxic lesion of the nigrostriatal pathway.
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Affiliation(s)
- David M Yurek
- Department of Neurosurgery, University of Kentucky College of Medicine, Lexington, KY 40536-0305, USA.
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48
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Boger HA, Granholm AC, McGinty JF, Middaugh LD. A dual-hit animal model for age-related parkinsonism. Prog Neurobiol 2010; 90:217-29. [PMID: 19853012 PMCID: PMC3991553 DOI: 10.1016/j.pneurobio.2009.10.013] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2009] [Revised: 06/08/2009] [Accepted: 10/09/2009] [Indexed: 12/30/2022]
Abstract
Parkinson's disease is a neurological disorder which afflicts an increasing number of individuals. If the wider complex of extrapyramidal symptoms referred to as "age-related parkinsonism" is included, the incidence is near 50% of the population above 80 years of age. This review summarizes recent studies from our laboratories as well as other research groups in the quest to explore the multi-faceted etiology of age-related neurodegeneration, in general, and degeneration of the substantia nigra dopaminergic neurons, in particular. Our work during recent years has focused on assessment of potential interactive effects of a reduction in glial cell line-derived neurotrophic factor (GDNF) and the aging process (intrinsic factors) and early neurotoxin exposure (an extrinsic factor) on dopamine (DA) systems and the behaviors they mediate. The guiding hypothesis directing the research to be described was that a combination of the two factors would exacerbate the decline in the DA transmitter system function that occurs during aging. The results obtained were consistent with the well-established aging-related decline in function and structure of neurons utilizing DA as a transmitter and motor function, and extended knowledge by establishing that the genetic reduction of Gdnf exacerbated these aging related changes. Thus, GDNF reduction appears to increase the vulnerability of the DA neurons to the many different challenges associated with the aging process. Assessment of methamphetamine effects on young Gdnf(+/-) mice indicated that reduced GDNF availability increased the vulnerability of DA systems to this well-established neurotoxin. The work discussed in this review is consistent with earlier work demonstrating the importance of GDNF for maintenance of DA neurons and also provides a novel model for progressive DA degeneration and motor dysfunction.
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Affiliation(s)
- Heather A Boger
- Department of Neurosciences, Medical University of South Carolina, Charleston, SC 29425, United States
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49
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Effect of nigrostriatal damage induced by 6-hydroxydopamine on the expression of glial cell line–derived neurotrophic factor in the striatum of the rat. Neuroscience 2009; 162:148-54. [DOI: 10.1016/j.neuroscience.2009.04.036] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2008] [Revised: 04/08/2009] [Accepted: 04/10/2009] [Indexed: 01/18/2023]
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50
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Yurek DM, Flectcher AM, Kowalczyk TH, Padegimas L, Cooper MJ. Compacted DNA nanoparticle gene transfer of GDNF to the rat striatum enhances the survival of grafted fetal dopamine neurons. Cell Transplant 2009; 18:1183-96. [PMID: 19650971 DOI: 10.3727/096368909x12483162196881] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Previously it was established that infusion of glial cell line-derived neurotrophic factor (GDNF) protein into grafts of embryonic dopamine cells has a neurotrophic effect on the grafted cells. In this study we used a nonviral technique to transfer the gene encoding for GDNF to striatal cells. Plasmid DNA encoding for GDNF was compacted into DNA nanoparticles (DNPs) by 10 kDa polyethylene glycol (PEG)-substituted lysine 30-mers (CK(30)PEG10k) and then injected into the denervated striatum of rats with unilateral 6-hydroxydopamine lesions. Sham controls were injected with saline. One week later, experimental animals received either a ventral mesencephalic (VM) tissue chunk graft or a cell suspension VM graft implanted into the denervated striatum. Grafts were allowed to integrate for 4-6 weeks and during this period we monitored spontaneous and drug-induced motor activity. Using stereological cell counting we observed a 16-fold increase in the number of surviving TH(+) cells within tissue chunk grafts placed into the striatum pretreated with pGDNF DNPs (14,923 +/- 4,326) when compared to grafts placed into striatum pretreated with saline (955 +/- 343). Similarly, we observed a sevenfold increase in the number of TH(+) cells within cell suspension grafts placed into the striatum treated with pGDNF DNPs when compared to cell suspension grafts placed into the saline dosed striatum. Behaviorally, we observed significant improvement in rotational scores and in spontaneous forepaw usage of the affected forelimb in grafted animals receiving prior treatment with compacted pGDNF DNPs when compared to grafted animals receiving saline control pretreatment. Data analysis for protein, morphological, and behavioral measures suggests that compacted pGDNF DNPs injected into the striatum can result in transfected cells overexpressing GDNF protein at levels that provide neurotrophic support for grafted embryonic dopamine neurons.
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Affiliation(s)
- David M Yurek
- Department of Neurosurgery, University of Kentucky College of Medicine, Lexington, KY 40536-0305, USA.
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