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Fishman-Jacob T, Youdim MBH. A sporadic Parkinson's disease model via silencing of the ubiquitin-proteasome/E3 ligase component, SKP1A. J Neural Transm (Vienna) 2023:10.1007/s00702-023-02687-6. [PMID: 37644186 DOI: 10.1007/s00702-023-02687-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 08/15/2023] [Indexed: 08/31/2023]
Abstract
Our and other's laboratory microarray-derived transcriptomic studies in human PD substantia nigra pars compacta (SNpc) samples have opened an avenue to concentrate on potential gene intersections or cross-talks along the dopaminergic (DAergic) neurodegenerative cascade in sporadic PD (SPD). One emerging gene candidate identified was SKP1A (p19, S-phase kinase-associated protein 1A), found significantly decreased in the SNpc as confirmed later at the protein level. SKP1 is part of the Skp1, Cullin 1, F-box protein (SCF) complex, the largest known class of sophisticated ubiquitin-proteasome/E3-ligases and was found to directly interact with FBXO7, a gene defective in PARK15-linked PD. This finding has led us to the hypothesis that a targeted site-specific reduction of Skp1 levels in DAergic neuronal cell culture and animal systems may result in a progressive loss of DAergic neurons and hopefully recreate motor disabilities in animals. The second premise considers the possibility that both intrinsic and extrinsic factors (e.g., manipulation of selected genes and mitochondria impairing toxins), alleged to play central roles in DAergic neurodegeneration in PD, may act in concert as modifiers of Skp1 deficiency-induced phenotype alterations ('dual-hit' hypothesis of neurodegeneration). To examine a possible role of Skp1 in DAergic phenotype, we have initially knocked down the expression of SKP1A gene in an embryonic mouse SN-derived cell line (SN4741) with short hairpin RNA (shRNA) lentiviruses (LVs). The deficiency of SKP1A closely recapitulated cardinal features of the DAergic pathology of human PD, such as decreased expression of DAergic phenotypic markers and cell cycle aberrations. Furthermore, the knocked down cells displayed a lethal phenotype when induced to differentiate exhibiting proteinaceous round inclusion structures, which were almost identical in composition to human Lewy bodies, a hallmark of PD. These findings support a role for Skp1 in neuronal phenotype, survival, and differentiation. The identification of Skp1 as a key player in DAergic neuron function suggested that a targeted site-specific reduction of Skp1 levels in mice SNpc may result in a progressive loss of DAergic neurons and terminal projections in the striatum. The injected LV SKP1shRNA to mouse SN resulted in decreased expression of Skp1 protein levels within DAergic neurons and loss of tyrosine hydroxylase immunoreactivity (TH-IR) in both SNpc and striatum that was accompanied by time-dependent motor disabilities. The reduction of the vertical movements, that is rearing, may be reminiscent of the early occurrence of hypokinesia and axial, postural instability in PD. According to the 'dual-hit' hypothesis of neurodegenerative diseases, it is predicted that gene-gene and/or gene-environmental factors would act in concert or sequentially to propagate the pathological process of PD. Our findings are compatible with this conjecture showing that the genetic vulnerability caused by knock down of SKP1A renders DAergic SN4741 cells especially sensitive to genetic reduction of Aldh1 and exposure to the external stressors MPP+ and DA, which have been implicated in PD pathology. Future consideration should be given in manipulation SKP1A expression as therapeutic window, via its induction genetically or pharmacological, to prevent degeneration of the nigra striatal dopamine neurons, since UPS is defective.
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Affiliation(s)
- Tali Fishman-Jacob
- Youdim Pharmaceutical Ltd, New Northern Industrial Park, 1 Ha- Tsmikha St, Stern Building, Fl-3, P. O. Box 72, 2069207, Yokneam, Israel
| | - Moussa B H Youdim
- Youdim Pharmaceutical Ltd, New Northern Industrial Park, 1 Ha- Tsmikha St, Stern Building, Fl-3, P. O. Box 72, 2069207, Yokneam, Israel.
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Geribaldi-Doldán N, Carrascal L, Pérez-García P, Oliva-Montero JM, Pardillo-Díaz R, Domínguez-García S, Bernal-Utrera C, Gómez-Oliva R, Martínez-Ortega S, Verástegui C, Nunez-Abades P, Castro C. Migratory Response of Cells in Neurogenic Niches to Neuronal Death: The Onset of Harmonic Repair? Int J Mol Sci 2023; 24:ijms24076587. [PMID: 37047560 PMCID: PMC10095545 DOI: 10.3390/ijms24076587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 03/23/2023] [Accepted: 03/27/2023] [Indexed: 04/05/2023] Open
Abstract
Harmonic mechanisms orchestrate neurogenesis in the healthy brain within specific neurogenic niches, which generate neurons from neural stem cells as a homeostatic mechanism. These newly generated neurons integrate into existing neuronal circuits to participate in different brain tasks. Despite the mechanisms that protect the mammalian brain, this organ is susceptible to many different types of damage that result in the loss of neuronal tissue and therefore in alterations in the functionality of the affected regions. Nevertheless, the mammalian brain has developed mechanisms to respond to these injuries, potentiating its capacity to generate new neurons from neural stem cells and altering the homeostatic processes that occur in neurogenic niches. These alterations may lead to the generation of new neurons within the damaged brain regions. Notwithstanding, the activation of these repair mechanisms, regeneration of neuronal tissue within brain injuries does not naturally occur. In this review, we discuss how the different neurogenic niches respond to different types of brain injuries, focusing on the capacity of the progenitors generated in these niches to migrate to the injured regions and activate repair mechanisms. We conclude that the search for pharmacological drugs that stimulate the migration of newly generated neurons to brain injuries may result in the development of therapies to repair the damaged brain tissue.
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Affiliation(s)
- Noelia Geribaldi-Doldán
- Departamento de Anatomía y Embriología Humanas, Facultad de Medicina, Universidad de Cádiz, 11003 Cádiz, Spain
- Instituto de Investigación e Innovación Biomédica de Cádiz (INiBICA), 11009 Cádiz, Spain
| | - Livia Carrascal
- Instituto de Investigación e Innovación Biomédica de Cádiz (INiBICA), 11009 Cádiz, Spain
- Departamento de Fisiología, Facultad de Farmacia, Universidad de Sevilla, 41012 Sevilla, Spain
| | - Patricia Pérez-García
- Instituto de Investigación e Innovación Biomédica de Cádiz (INiBICA), 11009 Cádiz, Spain
- Departamento de Biomedicina, Biotecnología y Salud Pública, Área de Fisiología, Facultad de Medicina, Universidad de Cádiz, 11003 Cádiz, Spain
| | - José M. Oliva-Montero
- Instituto de Investigación e Innovación Biomédica de Cádiz (INiBICA), 11009 Cádiz, Spain
- Departamento de Biomedicina, Biotecnología y Salud Pública, Área de Fisiología, Facultad de Medicina, Universidad de Cádiz, 11003 Cádiz, Spain
| | - Ricardo Pardillo-Díaz
- Instituto de Investigación e Innovación Biomédica de Cádiz (INiBICA), 11009 Cádiz, Spain
- Departamento de Biomedicina, Biotecnología y Salud Pública, Área de Fisiología, Facultad de Medicina, Universidad de Cádiz, 11003 Cádiz, Spain
| | - Samuel Domínguez-García
- Instituto de Investigación e Innovación Biomédica de Cádiz (INiBICA), 11009 Cádiz, Spain
- Departamento de Biomedicina, Biotecnología y Salud Pública, Área de Fisiología, Facultad de Medicina, Universidad de Cádiz, 11003 Cádiz, Spain
- Department of Neuroscience, Karolinska Institutet, Biomedicum, 17177 Stockholm, Sweden
| | - Carlos Bernal-Utrera
- Instituto de Investigación e Innovación Biomédica de Cádiz (INiBICA), 11009 Cádiz, Spain
- Departamento de Fisioterapia, Facultad de Enfermería, Fisioterapia y Podología, Universidad de Sevilla, 41009 Sevilla, Spain
| | - Ricardo Gómez-Oliva
- Instituto de Investigación e Innovación Biomédica de Cádiz (INiBICA), 11009 Cádiz, Spain
- Departamento de Biomedicina, Biotecnología y Salud Pública, Área de Fisiología, Facultad de Medicina, Universidad de Cádiz, 11003 Cádiz, Spain
| | - Sergio Martínez-Ortega
- Instituto de Investigación e Innovación Biomédica de Cádiz (INiBICA), 11009 Cádiz, Spain
- Departamento de Biomedicina, Biotecnología y Salud Pública, Área de Fisiología, Facultad de Medicina, Universidad de Cádiz, 11003 Cádiz, Spain
| | - Cristina Verástegui
- Departamento de Anatomía y Embriología Humanas, Facultad de Medicina, Universidad de Cádiz, 11003 Cádiz, Spain
- Instituto de Investigación e Innovación Biomédica de Cádiz (INiBICA), 11009 Cádiz, Spain
| | - Pedro Nunez-Abades
- Instituto de Investigación e Innovación Biomédica de Cádiz (INiBICA), 11009 Cádiz, Spain
- Departamento de Fisiología, Facultad de Farmacia, Universidad de Sevilla, 41012 Sevilla, Spain
| | - Carmen Castro
- Instituto de Investigación e Innovación Biomédica de Cádiz (INiBICA), 11009 Cádiz, Spain
- Departamento de Biomedicina, Biotecnología y Salud Pública, Área de Fisiología, Facultad de Medicina, Universidad de Cádiz, 11003 Cádiz, Spain
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Marchetti B, Giachino C, Tirolo C, Serapide MF. "Reframing" dopamine signaling at the intersection of glial networks in the aged Parkinsonian brain as innate Nrf2/Wnt driver: Therapeutical implications. Aging Cell 2022; 21:e13575. [PMID: 35262262 PMCID: PMC9009237 DOI: 10.1111/acel.13575] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 01/11/2022] [Accepted: 02/06/2022] [Indexed: 11/30/2022] Open
Abstract
Dopamine (DA) signaling via G protein‐coupled receptors is a multifunctional neurotransmitter and neuroendocrine–immune modulator. The DA nigrostriatal pathway, which controls the motor coordination, progressively degenerates in Parkinson's disease (PD), a most common neurodegenerative disorder (ND) characterized by a selective, age‐dependent loss of substantia nigra pars compacta (SNpc) neurons, where DA itself is a primary source of oxidative stress and mitochondrial impairment, intersecting astrocyte and microglial inflammatory networks. Importantly, glia acts as a preferential neuroendocrine–immune DA target, in turn, counter‐modulating inflammatory processes. With a major focus on DA intersection within the astrocyte–microglial inflammatory network in PD vulnerability, we herein first summarize the characteristics of DA signaling systems, the propensity of DA neurons to oxidative stress, and glial inflammatory triggers dictating the vulnerability to PD. Reciprocally, DA modulation of astrocytes and microglial reactivity, coupled to the synergic impact of gene–environment interactions, then constitute a further level of control regulating midbrain DA neuron (mDAn) survival/death. Not surprisingly, within this circuitry, DA converges to modulate nuclear factor erythroid 2‐like 2 (Nrf2), the master regulator of cellular defense against oxidative stress and inflammation, and Wingless (Wnt)/β‐catenin signaling, a key pathway for mDAn neurogenesis, neuroprotection, and immunomodulation, adding to the already complex “signaling puzzle,” a novel actor in mDAn–glial regulatory machinery. Here, we propose an autoregulatory feedback system allowing DA to act as an endogenous Nrf2/Wnt innate modulator and trace the importance of DA receptor agonists applied to the clinic as immune modifiers.
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Affiliation(s)
- Bianca Marchetti
- Department of Biomedical and Biotechnological Sciences (BIOMETEC) Pharmacology Section Medical School University of Catania Catania Italy
- OASI Research Institute‐IRCCS, Troina (EN), Italy Troina Italy
| | | | - Cataldo Tirolo
- OASI Research Institute‐IRCCS, Troina (EN), Italy Troina Italy
| | - Maria F. Serapide
- Department of Biomedical and Biotechnological Sciences (BIOMETEC) Pharmacology Section Medical School University of Catania Catania Italy
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Marchetti B, Leggio L, L’Episcopo F, Vivarelli S, Tirolo C, Paternò G, Giachino C, Caniglia S, Serapide MF, Iraci N. Glia-Derived Extracellular Vesicles in Parkinson's Disease. J Clin Med 2020; 9:jcm9061941. [PMID: 32575923 PMCID: PMC7356371 DOI: 10.3390/jcm9061941] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 06/12/2020] [Accepted: 06/17/2020] [Indexed: 12/15/2022] Open
Abstract
Glial cells are fundamental players in the central nervous system (CNS) development and homeostasis, both in health and disease states. In Parkinson’s disease (PD), a dysfunctional glia-neuron crosstalk represents a common final pathway contributing to the chronic and progressive death of dopaminergic (DAergic) neurons of the substantia nigra pars compacta (SNpc). Notably, glial cells communicating with each other by an array of molecules, can acquire a “beneficial” or “destructive” phenotype, thereby enhancing neuronal death/vulnerability and/or exerting critical neuroprotective and neuroreparative functions, with mechanisms that are actively investigated. An important way of delivering messenger molecules within this glia-neuron cross-talk consists in the secretion of extracellular vesicles (EVs). EVs are nano-sized membranous particles able to convey a wide range of molecular cargoes in a controlled way, depending on the specific donor cell and the microenvironmental milieu. Given the dual role of glia in PD, glia-derived EVs may deliver molecules carrying various messages for the vulnerable/dysfunctional DAergic neurons. Here, we summarize the state-of-the-art of glial-neuron interactions and glia-derived EVs in PD. Also, EVs have the ability to cross the blood brain barrier (BBB), thus acting both within the CNS and outside, in the periphery. In these regards, this review discloses the emerging applications of EVs, with a special focus on glia-derived EVs as potential carriers of new biomarkers and nanotherapeutics for PD.
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Affiliation(s)
- Bianca Marchetti
- Department of Biomedical and Biotechnological Sciences (BIOMETEC), University of Catania, Torre Biologica, Via S. Sofia 97, 95125 Catania, Italy; (L.L.); (S.V.); (G.P.); (M.F.S.)
- Neuropharmacology Section, OASI Research Institute-IRCCS, 94018 Troina, Italy; (F.L.); (C.T.); (C.G.); (S.C.)
- Correspondence: (B.M.); (N.I.)
| | - Loredana Leggio
- Department of Biomedical and Biotechnological Sciences (BIOMETEC), University of Catania, Torre Biologica, Via S. Sofia 97, 95125 Catania, Italy; (L.L.); (S.V.); (G.P.); (M.F.S.)
| | - Francesca L’Episcopo
- Neuropharmacology Section, OASI Research Institute-IRCCS, 94018 Troina, Italy; (F.L.); (C.T.); (C.G.); (S.C.)
| | - Silvia Vivarelli
- Department of Biomedical and Biotechnological Sciences (BIOMETEC), University of Catania, Torre Biologica, Via S. Sofia 97, 95125 Catania, Italy; (L.L.); (S.V.); (G.P.); (M.F.S.)
| | - Cataldo Tirolo
- Neuropharmacology Section, OASI Research Institute-IRCCS, 94018 Troina, Italy; (F.L.); (C.T.); (C.G.); (S.C.)
| | - Greta Paternò
- Department of Biomedical and Biotechnological Sciences (BIOMETEC), University of Catania, Torre Biologica, Via S. Sofia 97, 95125 Catania, Italy; (L.L.); (S.V.); (G.P.); (M.F.S.)
| | - Carmela Giachino
- Neuropharmacology Section, OASI Research Institute-IRCCS, 94018 Troina, Italy; (F.L.); (C.T.); (C.G.); (S.C.)
| | - Salvatore Caniglia
- Neuropharmacology Section, OASI Research Institute-IRCCS, 94018 Troina, Italy; (F.L.); (C.T.); (C.G.); (S.C.)
| | - Maria Francesca Serapide
- Department of Biomedical and Biotechnological Sciences (BIOMETEC), University of Catania, Torre Biologica, Via S. Sofia 97, 95125 Catania, Italy; (L.L.); (S.V.); (G.P.); (M.F.S.)
| | - Nunzio Iraci
- Department of Biomedical and Biotechnological Sciences (BIOMETEC), University of Catania, Torre Biologica, Via S. Sofia 97, 95125 Catania, Italy; (L.L.); (S.V.); (G.P.); (M.F.S.)
- Correspondence: (B.M.); (N.I.)
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Serapide MF, L'Episcopo F, Tirolo C, Testa N, Caniglia S, Giachino C, Marchetti B. Boosting Antioxidant Self-defenses by Grafting Astrocytes Rejuvenates the Aged Microenvironment and Mitigates Nigrostriatal Toxicity in Parkinsonian Brain via an Nrf2-Driven Wnt/β-Catenin Prosurvival Axis. Front Aging Neurosci 2020; 12:24. [PMID: 32226376 PMCID: PMC7081734 DOI: 10.3389/fnagi.2020.00024] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Accepted: 01/22/2020] [Indexed: 12/19/2022] Open
Abstract
Astrocyte (As) bidirectional dialog with neurons plays a fundamental role in major homeostatic brain functions, particularly providing metabolic support and antioxidant self-defense against reactive oxygen (ROS) and nitrogen species (RNS) via the activation of NF-E2-related factor 2 (Nrf2), a master regulator of oxidative stress. Disruption of As-neuron crosstalk is chiefly involved in neuronal degeneration observed in Parkinson's disease (PD), the most common movement disorder characterized by the selective degeneration of dopaminergic (DAergic) cell bodies of the substantia nigra (SN) pars compacta (SNpc). Ventral midbrain (VM)-As are recognized to exert an important role in DAergic neuroprotection via the expression of a variety of factors, including wingless-related MMTV integration site 1 (Wnt1), a principal player in DAergic neurogenesis. However, whether As, by themselves, might fulfill the role of chief players in DAergic neurorestoration of aged PD mice is presently unresolved. Here, we used primary postnatal mouse VM-As as a graft source for unilateral transplantation above the SN of aged 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mice after the onset of motor symptoms. Spatio-temporal analyses documented that the engrafted cells promoted: (i) a time-dependent nigrostriatal rescue along with increased high-affinity synaptosomal DA uptake and counteraction of motor deficit, as compared to mock-grafted counterparts; and (ii) a restoration of the impaired microenvironment via upregulation of As antioxidant self-defense through the activation of Nrf2/Wnt/β-catenin signaling, suggesting that grafting As has the potential to switch the SN neurorescue-unfriendly environment to a beneficial antioxidant/anti-inflammatory prosurvival milieu. These findings highlight As-derived factors/mechanisms as the crucial key for successful therapeutic outcomes in PD.
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Affiliation(s)
- Maria Francesca Serapide
- Pharmacology Section, Department of Biomedical and Biotechnological Sciences, Medical School, University of Catania, Catania, Italy
| | | | - Cataldo Tirolo
- Section of Neuropharmacology, OASI Research Institute-IRCCS, Troina, Italy
| | - Nunzio Testa
- Section of Neuropharmacology, OASI Research Institute-IRCCS, Troina, Italy
| | - Salvatore Caniglia
- Section of Neuropharmacology, OASI Research Institute-IRCCS, Troina, Italy
| | - Carmela Giachino
- Section of Neuropharmacology, OASI Research Institute-IRCCS, Troina, Italy
| | - Bianca Marchetti
- Pharmacology Section, Department of Biomedical and Biotechnological Sciences, Medical School, University of Catania, Catania, Italy.,Section of Neuropharmacology, OASI Research Institute-IRCCS, Troina, Italy
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Marchetti B, Tirolo C, L'Episcopo F, Caniglia S, Testa N, Smith JA, Pluchino S, Serapide MF. Parkinson's disease, aging and adult neurogenesis: Wnt/β-catenin signalling as the key to unlock the mystery of endogenous brain repair. Aging Cell 2020; 19:e13101. [PMID: 32050297 PMCID: PMC7059166 DOI: 10.1111/acel.13101] [Citation(s) in RCA: 96] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 11/27/2019] [Accepted: 12/25/2019] [Indexed: 12/14/2022] Open
Abstract
A common hallmark of age-dependent neurodegenerative diseases is an impairment of adult neurogenesis. Wingless-type mouse mammary tumor virus integration site (Wnt)/β-catenin (WβC) signalling is a vital pathway for dopaminergic (DAergic) neurogenesis and an essential signalling system during embryonic development and aging, the most critical risk factor for Parkinson's disease (PD). To date, there is no known cause or cure for PD. Here we focus on the potential to reawaken the impaired neurogenic niches to rejuvenate and repair the aged PD brain. Specifically, we highlight WβC-signalling in the plasticity of the subventricular zone (SVZ), the largest germinal region in the mature brain innervated by nigrostriatal DAergic terminals, and the mesencephalic aqueduct-periventricular region (Aq-PVR) Wnt-sensitive niche, which is in proximity to the SNpc and harbors neural stem progenitor cells (NSCs) with DAergic potential. The hallmark of the WβC pathway is the cytosolic accumulation of β-catenin, which enters the nucleus and associates with T cell factor/lymphoid enhancer binding factor (TCF/LEF) transcription factors, leading to the transcription of Wnt target genes. Here, we underscore the dynamic interplay between DAergic innervation and astroglial-derived factors regulating WβC-dependent transcription of key genes orchestrating NSC proliferation, survival, migration and differentiation. Aging, inflammation and oxidative stress synergize with neurotoxin exposure in "turning off" the WβC neurogenic switch via down-regulation of the nuclear factor erythroid-2-related factor 2/Wnt-regulated signalosome, a key player in the maintenance of antioxidant self-defense mechanisms and NSC homeostasis. Harnessing WβC-signalling in the aged PD brain can thus restore neurogenesis, rejuvenate the microenvironment, and promote neurorescue and regeneration.
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Affiliation(s)
- Bianca Marchetti
- Department of Biomedical and Biotechnological Sciences (BIOMETEC)Pharmacology and Physiology SectionsMedical SchoolUniversity of CataniaCataniaItaly
- Neuropharmacology SectionOASI Research Institute‐IRCCSTroinaItaly
| | - Cataldo Tirolo
- Neuropharmacology SectionOASI Research Institute‐IRCCSTroinaItaly
| | | | | | - Nunzio Testa
- Neuropharmacology SectionOASI Research Institute‐IRCCSTroinaItaly
| | - Jayden A. Smith
- Department of Clinical Neurosciences and NIHR Biomedical Research CentreUniversity of CambridgeCambridgeUK
| | - Stefano Pluchino
- Department of Clinical Neurosciences and NIHR Biomedical Research CentreUniversity of CambridgeCambridgeUK
| | - Maria F. Serapide
- Department of Biomedical and Biotechnological Sciences (BIOMETEC)Pharmacology and Physiology SectionsMedical SchoolUniversity of CataniaCataniaItaly
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Dwyer Z, Rudyk C, Thompson A, Farmer K, Fenner B, Fortin T, Derksen A, Sun H, Hayley S. Leucine-rich repeat kinase-2 (LRRK2) modulates microglial phenotype and dopaminergic neurodegeneration. Neurobiol Aging 2020; 91:45-55. [PMID: 32247534 DOI: 10.1016/j.neurobiolaging.2020.02.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 01/23/2020] [Accepted: 02/15/2020] [Indexed: 12/21/2022]
Abstract
Leucine-rich repeat kinase 2 (LRRK2) is a common gene implicated in Parkinson's disease and many inflammatory processes. Thus, we assessed the role of LRRK2 in the context of endotoxin (lipopolysaccharide, LPS)-induced inflammation of the substantia nigra together with the environmental toxicant, paraquat, that has been implicated in PD. Here we found that LRRK2 ablation prevented the loss of dopaminergic neurons and behavioral deficits (motor) induced by LPS priming followed by paraquat exposure. The LRRK2 ablation also provoked a phenotypic shift in LPS-primed microglia cells. The LRRK2 deficiency reduced their "activated" morphology and upregulation of the inflammatory phagocytic regulator, WAVE2 (critical for actin remodeling), while the chemokine receptor, CX3CR1, was elevated in isolated CD11b+ myeloid cells. Furthermore, LRRK2 knockout attenuated the signs of oxidative stress and morphological changes induced in primary microglia by LPS treatment. However, induced WAVE2 expression together with LPS exposure in microglia overcame the inhibitory effects of LRRK2 knockout, suggesting WAVE2 may be acting downstream of LRRK2. Neither WAVE2 nor did LRRK2 knockout influence LPS-induced cytokine elevations in the microglia. We are the first to show the importance of LRRK2 in neurodegenerative and inflammatory processes in this multi-hit toxin model of PD. These data are consistent with the proposition that LRRK2 and WAVE2 are useful therapeutic targets for PD or other conditions with a prominent neuroinflammatory component.
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Affiliation(s)
- Zach Dwyer
- Department of Neuroscience, Carleton University, Ottawa, Ontario, Canada.
| | - Chris Rudyk
- Department of Neuroscience, Carleton University, Ottawa, Ontario, Canada
| | - Ashley Thompson
- Department of Neuroscience, Carleton University, Ottawa, Ontario, Canada
| | - Kyle Farmer
- Department of Neuroscience, Carleton University, Ottawa, Ontario, Canada
| | - Barbara Fenner
- Department of Neuroscience, Carleton University, Ottawa, Ontario, Canada
| | - Teresa Fortin
- Department of Neuroscience, Carleton University, Ottawa, Ontario, Canada
| | - Alexa Derksen
- Department of Neuroscience, Carleton University, Ottawa, Ontario, Canada
| | - Hongyu Sun
- Department of Neuroscience, Carleton University, Ottawa, Ontario, Canada
| | - Shawn Hayley
- Department of Neuroscience, Carleton University, Ottawa, Ontario, Canada.
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- Department of Neuroscience, Carleton University, Ottawa, Ontario, Canada
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Characterization of Motor and Non-Motor Behavioral Alterations in the Dj-1 (PARK7) Knockout Rat. J Mol Neurosci 2019; 69:298-311. [PMID: 31250274 DOI: 10.1007/s12031-019-01358-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Accepted: 06/18/2019] [Indexed: 02/03/2023]
Abstract
Parkinson's disease is a neurodegenerative disorder that encompasses a constellation of motor and non-motor symptoms. The etiology of the disease is still poorly understood because of complex interactions between environmental and genetic risk factors. Using animal models to assess these risk factors may lead to a better understanding of disease manifestation. In this study, we assessed the Dj-1 knockout (KO) genetic rat model in a battery of motor and non-motor behaviors. We tested the Dj-1 KO rat, as well as age-matched wild-type (WT) control rats, in several sensorimotor tests at 2, 4, 7, and 13 months of age. The Dj-1-deficient rats were found to rear and groom less, and to have a shorter stride length than their WT counterparts, but to take more forelimb and hindlimb steps. In non-motor behavioral tasks, performed at several different ages, we evaluated the following: olfactory function, anxiety-like behavior, short-term memory, anhedonia, and stress coping behavior. Non-motor testing was conducted as early as 4.5 months and as late as 17 months of age. We found that Dj-1 KO animals displayed deficits in short-term spatial memory as early as 4.5 months of age during place preference testing, as well as impaired coping strategies in the forced swim test, which are consistent with a parkinsonian-like phenotype. In some instances, effects of chronic stress were evaluated in the Dj-1-deficient rats, as an initial test of an environmental challenge combined with a genetic disposition for PD. Although some of the results were mixed with differential effects across several of the behaviors, the combination of the changes we observed indicates that the Dj-1 KO rat may be a promising model for the assessment of the prodromal stage of Parkinson's disease, but further evaluation is necessary.
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Bhatia TN, Pant DB, Eckhoff EA, Gongaware RN, Do T, Hutchison DF, Gleixner AM, Leak RK. Astrocytes Do Not Forfeit Their Neuroprotective Roles After Surviving Intense Oxidative Stress. Front Mol Neurosci 2019; 12:87. [PMID: 31024254 PMCID: PMC6460290 DOI: 10.3389/fnmol.2019.00087] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Accepted: 03/21/2019] [Indexed: 12/16/2022] Open
Abstract
In order to fulfill their evolutionary role as support cells, astrocytes have to tolerate intense oxidative stress under conditions of brain injury and disease. It is well known that astrocytes exposed to mild oxidative stress are preconditioned against subsequent stress exposure in dual hit models. However, it is unclear whether severe oxidative stress leads to stress tolerance, stress exacerbation, or no change in stress resistance in astrocytes. Furthermore, it is not known whether reactive astrocytes surviving intense oxidative stress can still support nearby neurons. The data in this Brief Report suggest that primary cortical astrocytes surviving high concentrations of the oxidative toxicant paraquat are completely resistant against subsequent oxidative challenges of the same intensity. Inhibitors of multiple endogenous defenses (e.g., glutathione, heme oxygenase 1, ERK1/2, Akt) failed to abolish or even reduce their stress resistance. Stress-reactive cortical astrocytes surviving intense oxidative stress still managed to protect primary cortical neurons against subsequent oxidative injuries in neuron/astrocyte co-cultures, even at concentrations of paraquat that otherwise led to more than 80% neuron loss. Although our previous work demonstrated a lack of stress tolerance in primary neurons exposed to dual paraquat hits, here we show that intensely stressed primary neurons can resist a second hit of hydrogen peroxide. These collective findings suggest that stress-reactive astroglia are not necessarily neurotoxic, and that severe oxidative stress does not invariably lead to stress exacerbation in either glia or neurons. Therefore, interference with the natural functions of stress-reactive astrocytes might have the unintended consequence of accelerating neurodegeneration.
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Affiliation(s)
- Tarun N Bhatia
- Graduate School of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA, United States
| | - Deepti B Pant
- Graduate School of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA, United States
| | - Elizabeth A Eckhoff
- Graduate School of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA, United States
| | - Rachel N Gongaware
- Graduate School of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA, United States
| | - Timothy Do
- Graduate School of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA, United States
| | - Daniel F Hutchison
- Graduate School of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA, United States
| | - Amanda M Gleixner
- Graduate School of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA, United States
| | - Rehana K Leak
- Graduate School of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA, United States
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11
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Ghatak S, Trudler D, Dolatabadi N, Ambasudhan R. Parkinson's disease: what the model systems have taught us so far. J Genet 2018; 97:729-751. [PMID: 30027906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Parkinson's disease (PD) is a debilitating neurodegenerative disorder, for which people above the age of 60 show an increased risk. Although there has been great advancement in understanding the disease-related abnormalities in brain circuitry and development of symptomatic treatments, a cure for PD remains elusive. The discovery of PD associated gene mutations and environmental toxins have yielded animal models of the disease. These models could recapitulate several key aspects of PD, and provide more insights into the disease pathogenesis. They have also revealed novel aspects of the disease mechanism including noncell autonomous events and spreading of pathogenic protein species across the brain. Nevertheless, none of these models so far can comprehensively represent all aspects of the human disease. While the field is still searching for the perfect model system, recent developments in stem cell biology have provided a new dimension to modelling PD, especially doing it in a patient-specific manner. In the current review, we attempt to summarize the key findings in the areas discussed above, and highlight how the core PD pathology distinguishes itself from other neurodegenerative disorders while also resembling them in many aspects.
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Affiliation(s)
- Swagata Ghatak
- Neurodegenerative Disease Center, Scintillon Institute, San Diego, CA 92121, USA.
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12
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Weilnau JN, Carcella MA, Miner KM, Bhatia TN, Hutchison DF, Pant DB, Nouraei N, Leak RK. Evidence for cross-hemispheric preconditioning in experimental Parkinson's disease. Brain Struct Funct 2018; 223:1255-1273. [PMID: 29103154 PMCID: PMC11061878 DOI: 10.1007/s00429-017-1552-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 10/19/2017] [Indexed: 12/12/2022]
Abstract
Dopamine loss and motor deficits in Parkinson's disease typically commence unilaterally and remain asymmetric for many years, raising the possibility that endogenous defenses slow the cross-hemispheric transmission of pathology. It is well-established that the biological response to subtoxic stress prepares cells to survive subsequent toxic challenges, a phenomenon known as preconditioning, tolerance, or stress adaptation. Here we demonstrate that unilateral striatal infusions of the oxidative toxicant 6-hydroxydopamine (6-OHDA) precondition the contralateral nigrostriatal pathway against the toxicity of a second 6-OHDA infusion in the opposite hemisphere. 6-OHDA-induced loss of dopaminergic terminals in the contralateral striatum was ablated by cross-hemispheric preconditioning, as shown by two independent markers of the dopaminergic phenotype, each measured by two blinded observers. Similarly, loss of dopaminergic somata in the contralateral substantia nigra was also abolished, according to two blinded measurements. Motor asymmetries in floor landings, forelimb contacts with a wall, and spontaneous turning behavior were consistent with these histological observations. Unilateral 6-OHDA infusions increased phosphorylation of the kinase ERK2 and expression of the antioxidant enzyme CuZn superoxide dismutase in both striata, consistent with our previous mechanistic work showing that these two proteins mediate preconditioning in dopaminergic cells. These findings support the existence of cross-hemispheric preconditioning in Parkinson's disease and suggest that dopaminergic neurons mount impressive natural defenses, despite their reputation as being vulnerable to oxidative injury. If these results generalize to humans, Parkinson's pathology may progress slowly and asymmetrically because exposure to a disease-precipitating insult induces bilateral upregulation of endogenous defenses and elicits cross-hemispheric preconditioning.
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Affiliation(s)
- Justin N Weilnau
- Division of Pharmaceutical Sciences, Duquesne University, 407 Mellon Hall, 600 Forbes Ave, Pittsburgh, PA, 15282, USA
| | - Michael A Carcella
- Division of Pharmaceutical Sciences, Duquesne University, 407 Mellon Hall, 600 Forbes Ave, Pittsburgh, PA, 15282, USA
| | - Kristin M Miner
- Division of Pharmaceutical Sciences, Duquesne University, 407 Mellon Hall, 600 Forbes Ave, Pittsburgh, PA, 15282, USA
| | - Tarun N Bhatia
- Division of Pharmaceutical Sciences, Duquesne University, 407 Mellon Hall, 600 Forbes Ave, Pittsburgh, PA, 15282, USA
| | - Daniel F Hutchison
- Division of Pharmaceutical Sciences, Duquesne University, 407 Mellon Hall, 600 Forbes Ave, Pittsburgh, PA, 15282, USA
| | - Deepti B Pant
- Division of Pharmaceutical Sciences, Duquesne University, 407 Mellon Hall, 600 Forbes Ave, Pittsburgh, PA, 15282, USA
| | - Negin Nouraei
- Division of Pharmaceutical Sciences, Duquesne University, 407 Mellon Hall, 600 Forbes Ave, Pittsburgh, PA, 15282, USA
| | - Rehana K Leak
- Division of Pharmaceutical Sciences, Duquesne University, 407 Mellon Hall, 600 Forbes Ave, Pittsburgh, PA, 15282, USA.
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13
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Leak RK. Conditioning Against the Pathology of Parkinson's disease. CONDITIONING MEDICINE 2018; 1:143-162. [PMID: 30370426 PMCID: PMC6200356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Parkinson's disease is delayed in clinical onset, asymmetric in initial appearance, and slow in progression. One explanation for these characteristics may be a boost in natural defenses after early exposure to mild cellular stress. As the patient ages and resilience recedes, however, stress levels may become sufficiently high that toxic cellular responses can no longer be curbed, culminating in inverted U-shaped stress-response curves as a function of disease duration. If dopaminergic systems are indeed capable of responding to mild stress with effective natural defenses, experimental models of Parkinson's disease should adhere to the principles of preconditioning, whereby stress exposure fortifies cells and tempers the toxic sequelae of subsequent stressors. Here, I review evidence favoring the efficacy of preconditioning in dopaminergic systems. Recent animal work also raises the possibility that cross-hemispheric preconditioning may arrest the spread of asymmetric Parkinson's pathology to the other side of the brain. Indeed, compensatory homeostatic systems have long been hypothesized to maintain neurological function until a threshold of cell loss is exceeded and are often displayed as inverted U-shaped curves. However, some stress responses assume an exponential or sigmoidal profile as a function of disease severity, suggesting end-stage deceleration of disease processes. Thus, surviving dopaminergic neurons may become progressively harder to kill, with the dorsal nigral tier dying slower due to superior baseline defenses, inducible conditioning capacity, or delayed dorsomedial nigral spread of disease. In addition, compensatory processes may be useful as biomarkers to distinguish "responder patients" from "nonresponders" before clinical trials. However, another possibility is that defenses are already maximally conditioned in most patients and no further boost is possible. A third alternative is that genuinely diseased human cells cannot be conditioned, in contrast to preclinical models, none of which faithfully recapitulate age-related human conditions. Disease-related "conditioning deficiencies" would then explain how Parkinson's pathology takes root, progressively shrinks defenses, and eventually kills the patient.
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Affiliation(s)
- Rehana K. Leak
- For correspondence please address: Rehana K. Leak,
Ph.D., Graduate School of Pharmaceutical Sciences, Duquesne University, 600
Forbes Ave, Pittsburgh, PA 15282, ,
412.396.4734
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14
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L'Episcopo F, Tirolo C, Serapide MF, Caniglia S, Testa N, Leggio L, Vivarelli S, Iraci N, Pluchino S, Marchetti B. Microglia Polarization, Gene-Environment Interactions and Wnt/β-Catenin Signaling: Emerging Roles of Glia-Neuron and Glia-Stem/Neuroprogenitor Crosstalk for Dopaminergic Neurorestoration in Aged Parkinsonian Brain. Front Aging Neurosci 2018; 10:12. [PMID: 29483868 PMCID: PMC5816064 DOI: 10.3389/fnagi.2018.00012] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 01/11/2018] [Indexed: 12/29/2022] Open
Abstract
Neuroinflammatory processes are recognized key contributory factors in Parkinson's disease (PD) physiopathology. While the causes responsible for the progressive loss of midbrain dopaminergic (mDA) neuronal cell bodies in the subtantia nigra pars compacta are poorly understood, aging, genetics, environmental toxicity, and particularly inflammation, represent prominent etiological factors in PD development. Especially, reactive astrocytes, microglial cells, and infiltrating monocyte-derived macrophages play dual beneficial/harmful effects, via a panel of pro- or anti-inflammatory cytokines, chemokines, neurotrophic and neurogenic transcription factors. Notably, with age, microglia may adopt a potent neurotoxic, pro-inflammatory “primed” (M1) phenotype when challenged with inflammatory or neurotoxic stimuli that hamper brain's own restorative potential and inhibit endogenous neurorepair mechanisms. In the last decade we have provided evidence for a major role of microglial crosstalk with astrocytes, mDA neurons and neural stem progenitor cells (NSCs) in the MPTP- (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-) mouse model of PD, and identified Wnt/β-catenin signaling, a pivotal morphogen for mDA neurodevelopment, neuroprotection, and neuroinflammatory modulation, as a critical actor in glia-neuron and glia-NSCs crosstalk. With age however, Wnt signaling and glia-NSC-neuron crosstalk become dysfunctional with harmful consequences for mDA neuron plasticity and repair. These findings are of importance given the deregulation of Wnt signaling in PD and the emerging link between most PD related genes, Wnt signaling and inflammation. Especially, in light of the expanding field of microRNAs and inflammatory PD-related genes as modulators of microglial-proinflammatory status, uncovering the complex molecular circuitry linking PD and neuroinflammation will permit the identification of new druggable targets for the cure of the disease. Here we summarize recent findings unveiling major microglial inflammatory and oxidative stress pathways converging in the regulation of Wnt/β-catenin signaling, and reciprocally, the ability of Wnt signaling pathways to modulate microglial activation in PD. Unraveling the key factors and conditons promoting the switch of the proinflammatory M1 microglia status into a neuroprotective and regenerative M2 phenotype will have important consequences for neuroimmune interactions and neuronal outcome under inflammatory and/or neurodegenerative conditions.
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Affiliation(s)
| | | | - Maria F Serapide
- Department of Biomedical and Biotechnological Sciences, Medical School, University of Catania, Catania, Italy
| | | | | | - Loredana Leggio
- Department of Biomedical and Biotechnological Sciences, Medical School, University of Catania, Catania, Italy
| | - Silvia Vivarelli
- Department of Biomedical and Biotechnological Sciences, Medical School, University of Catania, Catania, Italy
| | - Nunzio Iraci
- Department of Biomedical and Biotechnological Sciences, Medical School, University of Catania, Catania, Italy
| | - Stefano Pluchino
- Division of Stem Cell Neurobiology, Department of Clinical Neurosciences, Wellcome Trust-Medical Research Council Stem Cell Institute, NIHR Biomedical Research Centre, University of Cambridge, Cambridge, United Kingdom
| | - Bianca Marchetti
- Oasi ResearchInstitute-IRCCS, Troina, Italy.,Department of Biomedical and Biotechnological Sciences, Medical School, University of Catania, Catania, Italy
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Synergistic effects of influenza and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) can be eliminated by the use of influenza therapeutics: experimental evidence for the multi-hit hypothesis. NPJ PARKINSONS DISEASE 2017. [PMID: 28649618 PMCID: PMC5460228 DOI: 10.1038/s41531-017-0019-z] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Central Nervous System inflammation has been implicated in neurodegenerative disorders including Parkinson’s disease (Ransohoff, Science 353: 777–783, 2016; Kannarkat et al. J. Parkinsons Dis. 3: 493–514, 2013). Here, we examined if the H1N1 influenza virus (Studahl et al. Drugs 73: 131–158, 2013) could synergize with the parkinsonian toxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (Jackson-Lewis et al. in Mark LeDoux (ed) Movement Disorders: Genetics and Models: 287–306, Elsevier, 2015) to induce a greater microglial activation and loss of substantia nigra pars compacta dopaminergic neurons than either insult alone. H1N1-infected animals administered 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine exhibit a 20% greater loss of substantia nigra pars compacta dopaminergic neurons than occurs from the additive effects of H1N1 or 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine alone (p < 0.001). No synergistic effects were found in microglial activation. The synergistic dopaminergic neuron loss is eliminated by influenza vaccination or treatment with oseltamivir carboxylate. This work shows that multiple insults can induce synergistic effects; and even these small changes can be significant as it might allow one to cross a phenotypic disease threshold that would not occur from individual non-interacting exposures. Our observations also have important implications for public health, providing impetus for influenza vaccination or prompt treatment with anti-viral medications upon influenza diagnosis.
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16
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Gleixner AM, Posimo JM, Pant DB, Henderson MP, Leak RK. Astrocytes Surviving Severe Stress Can Still Protect Neighboring Neurons from Proteotoxic Injury. Mol Neurobiol 2016; 53:4939-60. [PMID: 26374549 PMCID: PMC4792804 DOI: 10.1007/s12035-015-9427-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 09/03/2015] [Indexed: 12/18/2022]
Abstract
Astrocytes are one of the major cell types to combat cellular stress and protect neighboring neurons from injury. In order to fulfill this important role, astrocytes must sense and respond to toxic stimuli, perhaps including stimuli that are severely stressful and kill some of the astrocytes. The present study demonstrates that primary astrocytes that managed to survive severe proteotoxic stress were protected against subsequent challenges. These findings suggest that the phenomenon of preconditioning or tolerance can be extended from mild to severe stress for this cell type. Astrocytic stress adaptation lasted at least 96 h, the longest interval tested. Heat shock protein 70 (Hsp70) was raised in stressed astrocytes, but inhibition of neither Hsp70 nor Hsp32 activity abolished their resistance against a second proteotoxic challenge. Only inhibition of glutathione synthesis abolished astrocytic stress adaptation, consistent with our previous report. Primary neurons were plated upon previously stressed astrocytes, and the cocultures were then exposed to another proteotoxic challenge. Severely stressed astrocytes were still able to protect neighboring neurons against this injury, and the protection was unexpectedly independent of glutathione synthesis. Stressed astrocytes were even able to protect neurons after simultaneous application of proteasome and Hsp70 inhibitors, which otherwise elicited synergistic, severe loss of neurons when applied together. Astrocyte-induced neuroprotection against proteotoxicity was not elicited with astrocyte-conditioned media, suggesting that physical cell-to-cell contacts may be essential. These findings suggest that astrocytes may adapt to severe stress so that they can continue to protect neighboring cell types from profound injury.
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Affiliation(s)
- Amanda M Gleixner
- Division of Pharmaceutical Sciences, Mylan School of Pharmacy, Duquesne University, 407 Mellon Hall, 600 Forbes Avenue, Pittsburgh, PA, 15282, USA
| | - Jessica M Posimo
- Division of Pharmaceutical Sciences, Mylan School of Pharmacy, Duquesne University, 407 Mellon Hall, 600 Forbes Avenue, Pittsburgh, PA, 15282, USA
| | - Deepti B Pant
- Division of Pharmaceutical Sciences, Mylan School of Pharmacy, Duquesne University, 407 Mellon Hall, 600 Forbes Avenue, Pittsburgh, PA, 15282, USA
| | - Matthew P Henderson
- Division of Pharmaceutical Sciences, Mylan School of Pharmacy, Duquesne University, 407 Mellon Hall, 600 Forbes Avenue, Pittsburgh, PA, 15282, USA
| | - Rehana K Leak
- Division of Pharmaceutical Sciences, Mylan School of Pharmacy, Duquesne University, 407 Mellon Hall, 600 Forbes Avenue, Pittsburgh, PA, 15282, USA.
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17
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Buhusi M, Olsen K, Yang BZ, Buhusi CV. Stress-Induced Executive Dysfunction in GDNF-Deficient Mice, A Mouse Model of Parkinsonism. Front Behav Neurosci 2016; 10:114. [PMID: 27445722 PMCID: PMC4914592 DOI: 10.3389/fnbeh.2016.00114] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 05/24/2016] [Indexed: 12/22/2022] Open
Abstract
Maladaptive reactivity to stress is linked to improper decision making, impulsivity, and discounting of delayed rewards. Chronic unpredictable stress (CUS) alters dopaminergic function, re-shapes dopaminergic circuits in key areas involved in decision making, and impairs prefrontal-cortex dependent response inhibition and working memory. Glial-derived neurotrophic factor (GDNF) is essential for regulating dopamine (DA) release in the basal ganglia and for the survival of dopaminergic neurons; GDNF-deficient mice are considered an animal model for aging-related Parkinsonism. Recently, GDNF expression in the striatum has been linked to resilience to stress. Here we investigated the effects of CUS on decision making in GDNF-heterozygous (HET) mice and their wild-type littermate controls (WT). Before CUS no differences in temporal discounting (TD) were found between genotypes. However, following CUS GDNF HET mice, having a partial reduction of GDNF levels, showed increased impulsive choice indexed by a reduction in percent Larger-Later (LL) choices in the TD paradigm, and a reduction in area under the TD curve. Moreover, stressed GDNF HET mice, but not their WT controls, showed decreased neuronal activation (number of cFos positive neurons) in the orbitofrontal cortex (OFC), nucleus accumbens (NA) core, and NA shell, suggestive of a maladaptive response to stress. Interestingly, area under the TD curve positively correlated with cFos activation in the NA core, and NA shell, but not with orbitofrontal activity. These results provide further evidence of the differential involvement of the OFC, NA core, and NA shell in impulsive choice, and identify GDNF-deficient mice as a double-hit (gene × environment) model of stress-related executive dysfunction, particularly relevant to substance abuse and Parkinson’s disease (PD).
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Affiliation(s)
- Mona Buhusi
- Department of Psychology, Interdisciplinary Program in Neuroscience, Utah State University Logan, UT, USA
| | - Kaitlin Olsen
- Department of Psychology, Interdisciplinary Program in Neuroscience, Utah State University Logan, UT, USA
| | - Benjamin Z Yang
- Department of Psychology, Interdisciplinary Program in Neuroscience, Utah State University Logan, UT, USA
| | - Catalin V Buhusi
- Department of Psychology, Interdisciplinary Program in Neuroscience, Utah State University Logan, UT, USA
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18
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Heinemann SD, Posimo JM, Mason DM, Hutchison DF, Leak RK. Synergistic stress exacerbation in hippocampal neurons: Evidence favoring the dual-hit hypothesis of neurodegeneration. Hippocampus 2016; 26:980-94. [PMID: 26934478 DOI: 10.1002/hipo.22580] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/27/2016] [Indexed: 12/21/2022]
Abstract
The dual-hit hypothesis of neurodegeneration states that severe stress sensitizes vulnerable cells to subsequent challenges so that the two hits are synergistic in their toxic effects. Although the hippocampus is vulnerable to a number of neurodegenerative disorders, there are no models of synergistic cell death in hippocampal neurons in response to combined proteotoxic and oxidative stressors, the two major characteristics of these diseases. Therefore, a relatively high-throughput dual-hit model of stress synergy was developed in primary hippocampal neurons. In order to increase the rigor of the study and strengthen the interpretations, three independent, unbiased viability assays were employed at multiple timepoints. Stress synergy was elicited when hippocampal neurons were treated with the proteasome inhibitor MG132 followed by exposure to the oxidative toxicant paraquat, but only after 48 h. MG132 and paraquat only elicited additive effects 24 h after the final hit and even loss of heat shock protein 70 activity and glutathione did not promote stress synergy at this early timepoint. Dual hits of MG132 elicited modest glutathione loss and slightly synergistic toxic effects 48 h after the second hit, but only at some concentrations and only according to two viability assays (metabolic fitness and cytoskeletal integrity). The thiol N-acetyl cysteine protected hippocampal neurons against dual MG132/MG132 hits but not dual MG132/paraquat hits. These findings support the view that proteotoxic and oxidative stress propel and propagate each other in hippocampal neurons, leading to synergistically toxic effects, but not as the default response and only after a delay. The neuronal stress synergy observed here lies in contrast to astrocytic responses to dual hits, because astrocytes that survive severe proteotoxic stress resist additional cell loss following second hits. In conclusion, a new model of hippocampal vulnerability was developed for the testing of therapies, because neuroprotective treatments that are effective against severe, synergistic stress are more likely to succeed in the clinic. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Scott D Heinemann
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, Pennsylvania
| | - Jessica M Posimo
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, Pennsylvania
| | - Daniel M Mason
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, Pennsylvania
| | - Daniel F Hutchison
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, Pennsylvania
| | - Rehana K Leak
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, Pennsylvania
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19
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Leak RK. Heat shock proteins in neurodegenerative disorders and aging. J Cell Commun Signal 2014; 8:293-310. [PMID: 25208934 DOI: 10.1007/s12079-014-0243-9] [Citation(s) in RCA: 113] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 09/01/2014] [Indexed: 12/20/2022] Open
Abstract
Many members of the heat shock protein family act in unison to refold or degrade misfolded proteins. Some heat shock proteins also directly interfere with apoptosis. These homeostatic functions are especially important in proteinopathic neurodegenerative diseases, in which specific proteins misfold, aggregate, and kill cells through proteotoxic stress. Heat shock protein levels may be increased or decreased in these disorders, with the direction of the response depending on the individual heat shock protein, the disease, cell type, and brain region. Aging is also associated with an accrual of proteotoxic stress and modulates expression of several heat shock proteins. We speculate that the increase in some heat shock proteins in neurodegenerative conditions may be partly responsible for the slow progression of these disorders, whereas the increase in some heat shock proteins with aging may help delay senescence. The protective nature of many heat shock proteins in experimental models of neurodegeneration supports these hypotheses. Furthermore, some heat shock proteins appear to be expressed at higher levels in longer-lived species. However, increases in heat shock proteins may be insufficient to override overwhelming proteotoxic stress or reverse the course of these conditions, because the expression of several other heat shock proteins and endogenous defense systems is lowered. In this review we describe a number of stress-induced changes in heat shock proteins as a function of age and neurodegenerative pathology, with an emphasis on the heat shock protein 70 (Hsp70) family and the two most common proteinopathic disorders of the brain, Alzheimer's and Parkinson's disease.
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Affiliation(s)
- Rehana K Leak
- Division of Pharmaceutical Sciences, Duquesne University, 600 Forbes Ave, Pittsburgh, PA, 15282, USA,
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20
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Unnithan AS, Jiang Y, Rumble JL, Pulugulla SH, Posimo JM, Gleixner AM, Leak RK. N-acetyl cysteine prevents synergistic, severe toxicity from two hits of oxidative stress. Neurosci Lett 2013; 560:71-6. [PMID: 24361774 DOI: 10.1016/j.neulet.2013.12.023] [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: 06/17/2013] [Revised: 11/12/2013] [Accepted: 12/10/2013] [Indexed: 12/21/2022]
Abstract
The two hit hypothesis of neurodegeneration states that cells that have been severely stressed once are more vulnerable to the negative impact of a second hit. In other words, the toxicity of two hits of severe stress may be synergistic in neurons. We previously developed a two hit model of proteotoxic neurodegeneration using the proteasome inhibitor MG132. In that study, we found that the potent antioxidant N-acetyl cysteine was able to protect against the toxicity associated with dual MG132 hits. N-acetyl cysteine has been shown to ameliorate cognitive deficits in Alzheimer's patients and to reduce the symptoms of blast injury in soldiers. These studies and many others in experimental models of neurodegeneration suggest that N-acetyl cysteine can protect neurons even when they are severely injured. In the present study, we tested the hypotheses that dual hits of hydrogen peroxide and paraquat would elicit synergistic neurodegeneration and that this extreme toxicity would be prevented by N-acetyl cysteine. The findings reveal for the first time that neuronal N2a cells are much more sensitive to oxidative stress from hydrogen peroxide treatment when they have been exposed previously to the same toxin. Two hits of hydrogen peroxide also caused severe loss of glutathione. N-acetyl cysteine attenuated the loss of glutathione and reduced the near-complete loss of cells after exposure to dual hydrogen peroxide hits. The present study supports the notion that N-acetyl cysteine can robustly protect against severe, unremitting oxidative stress in a glutathione-dependent manner.
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Affiliation(s)
- Ajay S Unnithan
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA 15282, USA
| | - Yiran Jiang
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA 15282, USA
| | - Jennifer L Rumble
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA 15282, USA
| | - Sree H Pulugulla
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA 15282, USA
| | - Jessica M Posimo
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA 15282, USA
| | - Amanda M Gleixner
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA 15282, USA
| | - Rehana K Leak
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA 15282, USA.
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21
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Karakostas T, Hsiang S, Boger H, Middaugh L, Granholm AC. Three-dimensional rodent motion analysis and neurodegenerative disorders. J Neurosci Methods 2013; 231:31-7. [PMID: 24129039 DOI: 10.1016/j.jneumeth.2013.09.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2013] [Revised: 09/08/2013] [Accepted: 09/09/2013] [Indexed: 11/30/2022]
Abstract
BACKGROUND Three-dimensional (3D) motion analysis is established in investigating, human pathological motion. In the field of gait, its use results in the objective identification of primary, and secondary causes of deviations, many current interventions are the result of pre- and post-testing, and it was shown recently that it can result in decreased number of surgeries and overall cost of care. Consequently, recent attempts have implemented 3D motion analysis using rat models to study, parkinsonism. However, to-date, a 3D user friendly analytical approach using rodent models to, identify etiologies of age-related motor impairment and accompanying pathologies has not been, implemented. NEW METHOD We have developed and presented all aspects of a 3D, three body-segment rodent model, to analyze motions of the lower, upper and head segments between rodents of parkinsonism-type and, normal aging during free walking. Our model does not require transformation matrices to describe the, position of each body-segment. Because body-segment positions are not considered to consist of three, rotations about the laboratory axes, the rotations are not sequence dependent. RESULTS Each body-segment demonstrated distinct 3D movement patterns. The parkinsonism-type, genotype walked slower with less range of motion, similarly to patients with parkinsonism. COMPARISON WITH EXISTING METHODS This is the first model considering the rodent's body as three, distinct segments. To the best of our knowledge, it is the first model to ever consider and report the 3D, head motion patterns. CONCLUSIONS This novel approach will allow unbiased analysis of spontaneous locomotion in mouse, models of parkinsonism or normal aging.
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Affiliation(s)
- Tasos Karakostas
- Motion Analysis Center and Sensory Motor Performance Program, Rehabilitation Institute of Chicago, Chicago, IL, USA; Department of Physical Therapy, Medical University of South Carolina, Charleston, SC, USA; Department of Orthopaedic Surgery, Northwestern University, Chicago, IL, USA.
| | - Simon Hsiang
- Department of Industrial Engineering, Texas Tech University, Lubbock, TX, USA
| | - Heather Boger
- Departments of Neurosciences and Psychiatry, and The Center on Aging, Medical University of South Carolina, Charleston, SC, USA
| | - Lawrence Middaugh
- Departments of Neurosciences and Psychiatry, and The Center on Aging, Medical University of South Carolina, Charleston, SC, USA
| | - Ann-Charlotte Granholm
- Departments of Neurosciences and Psychiatry, and The Center on Aging, Medical University of South Carolina, Charleston, SC, USA
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Kucinski A, Wersinger S, Stachowiak EK, Corso TD, Parry MJ, Zhang J, Jordan K, Letchworth S, Bencherif M, Stachowiak MK. Neuronal nicotinic receptor agonists ameliorate spontaneous motor asymmetries and motor discoordination in a unilateral mouse model of Parkinson's disease. Pharmacol Biochem Behav 2013; 111:1-10. [DOI: 10.1016/j.pbb.2013.07.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Revised: 06/21/2013] [Accepted: 07/03/2013] [Indexed: 12/24/2022]
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Abstract
Although severe stress can elicit toxicity, mild stress often elicits adaptations. Here we review the literature on stress-induced adaptations versus stress sensitization in models of neurodegenerative diseases. We also describe our recent findings that chronic proteotoxic stress can elicit adaptations if the dose is low but that high-dose proteotoxic stress sensitizes cells to subsequent challenges. In these experiments, long-term, low-dose proteasome inhibition elicited protection in a superoxide dismutase-dependent manner. In contrast, acute, high-dose proteotoxic stress sensitized cells to subsequent proteotoxic challenges by eliciting catastrophic loss of glutathione. However, even in the latter model of synergistic toxicity, several defensive proteins were upregulated by severe proteotoxicity. This led us to wonder whether high-dose proteotoxic stress can elicit protection against subsequent challenges in astrocytes, a cell type well known for their resilience. In support of this new hypothesis, we found that the astrocytes that survived severe proteotoxicity became harder to kill. The adaptive mechanism was glutathione dependent. If these findings can be generalized to the human brain, similar endogenous adaptations may help explain why neurodegenerative diseases are so delayed in appearance and so slow to progress. In contrast, sensitization to severe stress may explain why defenses eventually collapse in vulnerable neurons.
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Affiliation(s)
- Rehana K Leak
- Division of Pharmaceutical Sciences, Mylan School of Pharmacy, Duquesne University
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Willison LD, Kudo T, Loh DH, Kuljis D, Colwell CS. Circadian dysfunction may be a key component of the non-motor symptoms of Parkinson's disease: insights from a transgenic mouse model. Exp Neurol 2013; 243:57-66. [PMID: 23353924 PMCID: PMC3994881 DOI: 10.1016/j.expneurol.2013.01.014] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2012] [Revised: 12/20/2012] [Accepted: 01/15/2013] [Indexed: 01/09/2023]
Abstract
Sleep disorders are nearly ubiquitous among patients with Parkinson's disease (PD), and they manifest early in the disease process. While there are a number of possible mechanisms underlying these sleep disturbances, a primary dysfunction of the circadian system should be considered as a contributing factor. Our laboratory's behavioral phenotyping of a well-validated transgenic mouse model of PD reveals that the electrical activity of neurons within the master pacemaker of the circadian system, the suprachiasmatic nuclei (SCN), is already disrupted at the onset of motor symptoms, although the core features of the intrinsic molecular oscillations in the SCN remain functional. Our observations suggest that the fundamental circadian deficit in these mice lies in the signaling output from the SCN, which may be caused by known mechanisms in PD etiology: oxidative stress and mitochondrial disruption. Disruption of the circadian system is expected to have pervasive effects throughout the body and may itself lead to neurological and cardiovascular disorders. In fact, there is much overlap in the non-motor symptoms experienced by PD patients and in the consequences of circadian disruption. This raises the possibility that the sleep and circadian dysfunction experienced by PD patients may not merely be a subsidiary of the motor symptoms, but an integral part of the disease. Furthermore, we speculate that circadian dysfunction can even accelerate the pathology underlying PD. If these hypotheses are correct, more aggressive treatment of the circadian misalignment and sleep disruptions in PD patients early in the pathogenesis of the disease may be powerful positive modulators of disease progression and patient quality of life.
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Affiliation(s)
- L David Willison
- Division of Child and Adolescent Psychiatry, Laboratory of Circadian and Sleep Medicine, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA, USA
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Titler AM, Posimo JM, Leak RK. Astrocyte plasticity revealed by adaptations to severe proteotoxic stress. Cell Tissue Res 2013; 352:427-43. [PMID: 23420451 DOI: 10.1007/s00441-013-1571-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Accepted: 01/17/2013] [Indexed: 12/21/2022]
Abstract
Neurodegeneration is characterized by an accumulation of misfolded proteins in neurons. It is less well appreciated that glia often also accumulate misfolded proteins. However, glia are highly plastic and may adapt to stress readily. Endogenous adaptations to stress can be measured by challenging stressed cells with a second hit and then measuring viability. For example, subtoxic stress can elicit preconditioning or tolerance against second hits. However, it is not known if severe stress that kills half the population can elicit endogenous adaptations in the remaining survivors. Glia, with their resilient nature, offer an ideal model in which to test this new hypothesis. The present study is the first demonstration that astrocytes surviving one LC50 hit of the proteasome inhibitor MG132 were protected against a second MG132 hit. ATP loss in response to the second hit was also prevented. MG132 caused compensatory rises in stress-sensitive heat shock proteins. However, stressed astrocytes exhibited an even greater rise in ubiquitin-conjugated proteins upon the second hit, illustrating the severity of the proteotoxicity and verifying the continued impact of MG132. Despite this stress, MG132-pretreated astrocytes were completely prevented from losing glutathione with the second hit. Furthermore, inhibiting glutathione synthesis rendered astrocytes sensitive to the second hit, unmasking the cumulative impact of two hits by removal of an endogenous adaptation. These findings suggest that stressed astrocytes become progressively harder to kill by virtue of antioxidant defenses. Such plasticity may permit astrocytes under severe stress to better support neurons and help explain the protracted nature of neurodegeneration.
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Affiliation(s)
- Amanda M Titler
- Division of Pharmaceutical Sciences, Mylan School of Pharmacy, Duquesne University, 600 Forbes Ave, Pittsburgh, PA 15282, USA
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Rocha SM, Cristovão AC, Campos FL, Fonseca CP, Baltazar G. Astrocyte-derived GDNF is a potent inhibitor of microglial activation. Neurobiol Dis 2012; 47:407-15. [DOI: 10.1016/j.nbd.2012.04.014] [Citation(s) in RCA: 113] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2011] [Revised: 03/29/2012] [Accepted: 04/26/2012] [Indexed: 12/14/2022] Open
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Yadav S, Dixit A, Agrawal S, Singh A, Srivastava G, Singh AK, Srivastava PK, Prakash O, Singh MP. Rodent models and contemporary molecular techniques: notable feats yet incomplete explanations of Parkinson's disease pathogenesis. Mol Neurobiol 2012; 46:495-512. [PMID: 22736079 DOI: 10.1007/s12035-012-8291-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Accepted: 06/13/2012] [Indexed: 12/20/2022]
Abstract
Rodent models and molecular tools, mainly omics and RNA interference, have been rigorously used to decode the intangible etiology and pathogenesis of Parkinson's disease (PD). Although convention of contemporary molecular techniques and multiple rodent models paved imperative leads in deciphering the role of putative causative factors and sequential events leading to PD, complete and clear-cut mechanisms of pathogenesis are still hard to pin down. The current article reviews the implications and pros and cons of rodent models and molecular tools in understanding the molecular and cellular bases of PD pathogenesis based on the existing literature. Probable rationales for short of comprehensive leads and future possibilities in spite of the extensive applications of molecular tools and rodent models have also been discussed.
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Affiliation(s)
- Sharawan Yadav
- CSIR-Indian Institute of Toxicology Research, Lucknow-226 001, Uttar Pradesh, India
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Unnithan AS, Choi HJH, Titler AM, Posimo JM, Leak RK. Rescue from a two hit, high-throughput model of neurodegeneration with N-acetyl cysteine. Neurochem Int 2012; 61:356-68. [PMID: 22691629 DOI: 10.1016/j.neuint.2012.06.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2012] [Revised: 05/17/2012] [Accepted: 06/01/2012] [Indexed: 12/21/2022]
Abstract
Postmortem tissue from patients with neurodegeneration exhibits protein-misfolding stress and reduced proteasome activity. This hallmark burden of proteotoxic stress has led to the term "proteinopathies" for neurodegenerative diseases. Proteinopathies may also be exacerbated by previous insults, according to the two hit hypothesis of accelerated neurodegeneration. In order to model the response to two successive insults in a high-throughput fashion, we exposed the neuronal cell line N2a to two hits of the proteasome inhibitor MG132 and performed three unbiased viability assays. MG132 toxicity was synergistically exacerbated following sequential hits provided the first hit was high enough to be toxic. This accelerated viability loss was apparent by (1) a nuclear and cytoplasmic stain (DRAQ5+Sapphire), (2) immunocytochemistry for a cytoskeletal marker (α-tubulin), and (3) ATP levels (Cell Titer Glo). Ubiquitin-conjugated proteins were raised by toxic, but not subtoxic MG132, and were thus correlated with toxicity exacerbation at higher doses. We hypothesized that levels of autophagic and antioxidant defenses would be reduced with toxic, but not subtoxic MG132, explaining their differential impact on a second hit. However, proteins involved in chaperone-mediated autophagy were raised by toxic MG132, not reduced. Furthermore, inhibiting autophagy enhanced the toxicity of both subtoxic and toxic MG132 as well as of dual hits, suggesting that autophagic removal of cellular debris protected against proteasome inhibition. Two toxic hits of MG132 synergistically decreased the antioxidant glutathione. The glutathione precursor N-acetyl cysteine reversed this glutathione loss and prevented the toxic response to dual hits by all three assays. Dietary supplementation with N-acetyl cysteine benefits Alzheimer's patients and is currently undergoing clinical trials in Parkinson's disease. The present report is the first demonstration that this versatile compound is protective against synergistic loss of viability as well as of glutathione following unrelenting, sequential hits of proteotoxic stress as may occur in the diseased brain.
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Affiliation(s)
- Ajay S Unnithan
- Division of Pharmaceutical Sciences, Mylan School of Pharmacy, Duquesne University, Pittsburgh, PA 15282, USA
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29
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Genetic reduction of the E3 ubiquitin ligase element, SKP1A and environmental manipulation to emulate cardinal features of Parkinson's disease. Parkinsonism Relat Disord 2012; 18 Suppl 1:S177-9. [DOI: 10.1016/s1353-8020(11)70055-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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L'Episcopo F, Tirolo C, Testa N, Caniglia S, Morale MC, Impagnatiello F, Marchetti B. Switching the Microglial Harmful Phenotype Promotes Lifelong Restoration of Subtantia Nigra Dopaminergic Neurons from Inflammatory Neurodegeneration in Aged Mice. Rejuvenation Res 2011; 14:411-24. [DOI: 10.1089/rej.2010.1134] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Affiliation(s)
- Francesca L'Episcopo
- OASI Institute for Research and Care on Mental Retardation and Brain Aging, Neuropharmacology Section, Troina, Italy
| | - Cataldo Tirolo
- OASI Institute for Research and Care on Mental Retardation and Brain Aging, Neuropharmacology Section, Troina, Italy
| | - Nunzio Testa
- OASI Institute for Research and Care on Mental Retardation and Brain Aging, Neuropharmacology Section, Troina, Italy
| | - Salvatore Caniglia
- OASI Institute for Research and Care on Mental Retardation and Brain Aging, Neuropharmacology Section, Troina, Italy
| | - Maria Concetta Morale
- OASI Institute for Research and Care on Mental Retardation and Brain Aging, Neuropharmacology Section, Troina, Italy
| | | | - Bianca Marchetti
- OASI Institute for Research and Care on Mental Retardation and Brain Aging, Neuropharmacology Section, Troina, Italy
- Department of Clinical and Molecular Biomedicine, Pharmacology Section, Faculty of Medicine, Catania, Italy
- Faculty of Pharmacy, University of Catania, Catania, Italy
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Gao HM, Hong JS. Gene-environment interactions: key to unraveling the mystery of Parkinson's disease. Prog Neurobiol 2011; 94:1-19. [PMID: 21439347 PMCID: PMC3098527 DOI: 10.1016/j.pneurobio.2011.03.005] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Revised: 01/26/2011] [Accepted: 03/16/2011] [Indexed: 12/21/2022]
Abstract
Parkinson's disease (PD) is the second most common neurodegenerative disease. The gradual, irreversible loss of dopamine neurons in the substantia nigra is the signature lesion of PD. Clinical symptoms of PD become apparent when 50-60% of nigral dopamine neurons are lost. PD progresses insidiously for 5-7 years (preclinical period) and then continues to worsen even under the symptomatic treatment. To determine what triggers the disease onset and what drives the chronic, self-propelling neurodegenerative process becomes critical and urgent, since lack of such knowledge impedes the discovery of effective treatments to retard PD progression. At present, available therapeutics only temporarily relieve PD symptoms. While the identification of causative gene defects in familial PD uncovers important genetic influences in this disease, the majority of PD cases are sporadic and idiopathic. The current consensus suggests that PD develops from multiple risk factors including aging, genetic predisposition, and environmental exposure. Here, we briefly review research on the genetic and environmental causes of PD. We also summarize very recent genome-wide association studies on risk gene polymorphisms in the emergence of PD. We highlight the new converging evidence on gene-environment interplay in the development of PD with an emphasis on newly developed multiple-hit PD models involving both genetic lesions and environmental triggers.
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Affiliation(s)
- Hui-Ming Gao
- Neuropharmacology Section, Laboratory of Toxicology & Pharmacology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA.
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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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L’Episcopo F, Tirolo C, Testa N, Caniglia S, Morale M, Cossetti C, D’Adamo P, Zardini E, Andreoni L, Ihekwaba A, Serra P, Franciotta D, Martino G, Pluchino S, Marchetti B. Reactive astrocytes and Wnt/β-catenin signaling link nigrostriatal injury to repair in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine model of Parkinson's disease. Neurobiol Dis 2011; 41:508-27. [PMID: 21056667 PMCID: PMC3558878 DOI: 10.1016/j.nbd.2010.10.023] [Citation(s) in RCA: 153] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2010] [Revised: 10/15/2010] [Accepted: 10/27/2010] [Indexed: 02/07/2023] Open
Abstract
Emerging evidence points to reactive glia as a pivotal factor in Parkinson's disease (PD) and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-lesioned mouse model of basal ganglia injury, but whether astrocytes and microglia activation may exacerbate dopaminergic (DAergic) neuron demise and/or contribute to DAergic repair is presently the subject of much debate. Here, we have correlated the loss and recovery of the nigrostriatal DAergic functionality upon acute MPTP exposure with extensive gene expression analysis at the level of the ventral midbrain (VM) and striata (Str) and found a major upregulation of pro-inflammatory chemokines and wingless-type MMTV integration site1 (Wnt1), a key transcript involved in midbrain DAergic neurodevelopment. Wnt signaling components (including Frizzled-1 [Fzd-1] and β-catenin) were dynamically regulated during MPTP-induced DAergic degeneration and reactive glial activation. Activated astrocytes of the ventral midbrain were identified as candidate source of Wnt1 by in situ hybridization and real-time PCR in vitro. Blocking Wnt/Fzd signaling with Dickkopf-1 (Dkk1) counteracted astrocyte-induced neuroprotection against MPP(+) toxicity in primary mesencephalic astrocyte-neuron cultures, in vitro. Moreover, astroglial-derived factors, including Wnt1, promoted neurogenesis and DAergic neurogenesis from adult midbrain stem/neuroprogenitor cells, in vitro. Conversely, lack of Wnt1 transcription in response to MPTP in middle-aged mice and failure of DAergic neurons to recover were reversed by pharmacological activation of Wnt/β-catenin signaling, in vivo, thus suggesting MPTP-reactive astrocytes in situ and Wnt1 as candidate components of neuroprotective/neurorescue pathways in MPTP-induced nigrostriatal DAergic plasticity.
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Affiliation(s)
- F. L’Episcopo
- OASI Institute for Research and Care on Mental Retardation and Brain Aging, Neuropharmacology Section, Via Conte Ruggero 73, 94018 Troina (EN) Italy
| | - C. Tirolo
- OASI Institute for Research and Care on Mental Retardation and Brain Aging, Neuropharmacology Section, Via Conte Ruggero 73, 94018 Troina (EN) Italy
| | - N. Testa
- OASI Institute for Research and Care on Mental Retardation and Brain Aging, Neuropharmacology Section, Via Conte Ruggero 73, 94018 Troina (EN) Italy
| | - S. Caniglia
- OASI Institute for Research and Care on Mental Retardation and Brain Aging, Neuropharmacology Section, Via Conte Ruggero 73, 94018 Troina (EN) Italy
| | - M.C. Morale
- OASI Institute for Research and Care on Mental Retardation and Brain Aging, Neuropharmacology Section, Via Conte Ruggero 73, 94018 Troina (EN) Italy
| | - C. Cossetti
- Cambridge Centre for Brain Repair Department of Clinical Neurosciences ED Adrian Building Forvie Site Robinson Way Cambridge CB2 0PY, UK
| | - P. D’Adamo
- Molecular Genetics of Mental Retardation Unit, San Raffaele Institute, Via Olgettina, 58 I-20132 Milan, Italy
| | - E. Zardini
- Neuroimmunology Unit, National Neurological Instititute C. Mondino, Via Mondino 2, 27100 Pavia, Italy
| | - L. Andreoni
- Neuroimmunology Unit, National Neurological Instititute C. Mondino, Via Mondino 2, 27100 Pavia, Italy
| | - A.E.C. Ihekwaba
- Cambridge Centre for Brain Repair Department of Clinical Neurosciences ED Adrian Building Forvie Site Robinson Way Cambridge CB2 0PY, UK
| | - P.A. Serra
- Department of Pharmacology, University of Sassari, Medical School, Viale S. Pietro 43, 07100 Sassari, Italy
| | - D. Franciotta
- Department of Pharmacology, University of Sassari, Medical School, Viale S. Pietro 43, 07100 Sassari, Italy
| | - G. Martino
- San Raffaele Institute, Neuroimmunology Unit, DIBIT2 and Institute of Experimental Neurology (INSPE), Via Olgettina, 58 I-20132 Milan, Italy
| | - S. Pluchino
- Cambridge Centre for Brain Repair Department of Clinical Neurosciences ED Adrian Building Forvie Site Robinson Way Cambridge CB2 0PY, UK
| | - B. Marchetti
- OASI Institute for Research and Care on Mental Retardation and Brain Aging, Neuropharmacology Section, Via Conte Ruggero 73, 94018 Troina (EN) Italy
- Department of Clinical and Molecular Biomedicine, Pharmacology Section, University of Catania, Viale A. Doria, 95125 Catania, Italy
- Faculty of Pharmacy, University of Catania, Viale A. Doria, 95125 Catania, Italy
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L'Episcopo F, Tirolo C, Caniglia S, Testa N, Serra PA, Impagnatiello F, Morale MC, Marchetti B. Combining nitric oxide release with anti-inflammatory activity preserves nigrostriatal dopaminergic innervation and prevents motor impairment in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine model of Parkinson's disease. J Neuroinflammation 2010; 7:83. [PMID: 21092260 PMCID: PMC3000390 DOI: 10.1186/1742-2094-7-83] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2010] [Accepted: 11/23/2010] [Indexed: 01/05/2023] Open
Abstract
Background Current evidence suggests a role of neuroinflammation in the pathogenesis of Parkinson's disease (PD) and in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) model of basal ganglia injury. Reportedly, nonsteroidal anti-inflammatory drugs (NSAIDs) mitigate DAergic neurotoxicity in rodent models of PD. Consistent with these findings, epidemiological analysis indicated that certain NSAIDs may prevent or delay the progression of PD. However, a serious impediment of chronic NSAID therapy, particularly in the elderly, is gastric, renal and cardiac toxicity. Nitric oxide (NO)-donating NSAIDs, have a safer profile while maintaining anti-inflammatory activity of parent compounds. We have investigated the oral activity of the NO-donating derivative of flurbiprofen, [2-fluoro-α-methyl (1,1'-biphenyl)-4-acetic-4-(nitrooxy)butyl ester], HCT1026 (30 mg kg-1 daily in rodent chow) in mice exposed to the parkinsonian neurotoxin MPTP. Methods Ageing mice were fed with a control, flurbiprofen, or HCT1026 diet starting ten days before MPTP administration and continuing for all the experimental period. Striatal high affinity synaptosomial dopamine up-take, motor coordination assessed with the rotarod, tyrosine hydroxylase (TH)- and dopamine transporter (DAT) fiber staining, stereological cell counts, immunoblotting and gene expression analyses were used to assess MPTP-induced nigrostriatal DAergic toxicity and glial activation 1-40 days post-MPTP. Results HCT1026 was well tolerated and did not cause any measurable toxic effect, whereas flurbiprofen fed mice showed severe gastrointestinal side-effects. HCT1026 efficiently counteracted motor impairment and reversed MPTP-induced decreased synaptosomal [3H]dopamine uptake, TH- and DAT-stained fibers in striatum and TH+ neuron loss in subtantia nigra pars compacta (SNpc), as opposed to age-matched mice fed with a control diet. These effects were associated to a significant decrease in reactive macrophage antigen-1 (Mac-1)-positive microglial cells within the striatum and ventral midbrain, decreased expression of iNOS, Mac-1 and NADPH oxidase (PHOX), and downregulation of 3-Nitrotyrosine, a peroxynitrite finger print, in SNpc DAergic neurons. Conclusions Oral treatment with HCT1026 has a safe profile and a significant efficacy in counteracting MPTP-induced dopaminergic (DAergic) neurotoxicity, motor impairment and microglia activation in ageing mice. HCT1026 provides a novel promising approach towards the development of effective pharmacological neuroprotective strategies against PD.
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Affiliation(s)
- Francesca L'Episcopo
- OASI Institute for Research and Care on Mental Retardation and Brain Aging (IRCCS), Neuropharmacology Section, 94018 Troina, Italy
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