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Bruno A, Milillo C, Anaclerio F, Buccolini C, Dell’Elice A, Angilletta I, Gatta M, Ballerini P, Antonucci I. Perinatal Tissue-Derived Stem Cells: An Emerging Therapeutic Strategy for Challenging Neurodegenerative Diseases. Int J Mol Sci 2024; 25:976. [PMID: 38256050 PMCID: PMC10815412 DOI: 10.3390/ijms25020976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 01/05/2024] [Accepted: 01/09/2024] [Indexed: 01/24/2024] Open
Abstract
Over the past 20 years, stem cell therapy has been considered a promising option for treating numerous disorders, in particular, neurodegenerative disorders. Stem cells exert neuroprotective and neurodegenerative benefits through different mechanisms, such as the secretion of neurotrophic factors, cell replacement, the activation of endogenous stem cells, and decreased neuroinflammation. Several sources of stem cells have been proposed for transplantation and the restoration of damaged tissue. Over recent decades, intensive research has focused on gestational stem cells considered a novel resource for cell transplantation therapy. The present review provides an update on the recent preclinical/clinical applications of gestational stem cells for the treatment of protein-misfolding diseases including Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD) and amyotrophic lateral sclerosis (ALS). However, further studies should be encouraged to translate this promising therapeutic approach into the clinical setting.
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Affiliation(s)
- Annalisa Bruno
- Center for Advanced Studies and Technology (CAST), “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy; (A.B.); (C.M.); (C.B.); (A.D.); (I.A.)
- Department of Innovative Technologies in Medicine & Dentistry, “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy
| | - Cristina Milillo
- Center for Advanced Studies and Technology (CAST), “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy; (A.B.); (C.M.); (C.B.); (A.D.); (I.A.)
- Department of Psychological, Health and Territorial Sciences, “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy
| | - Federico Anaclerio
- Center for Advanced Studies and Technology (CAST), “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy; (A.B.); (C.M.); (C.B.); (A.D.); (I.A.)
- Department of Psychological, Health and Territorial Sciences, “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy
| | - Carlotta Buccolini
- Center for Advanced Studies and Technology (CAST), “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy; (A.B.); (C.M.); (C.B.); (A.D.); (I.A.)
- Department of Psychological, Health and Territorial Sciences, “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy
| | - Anastasia Dell’Elice
- Center for Advanced Studies and Technology (CAST), “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy; (A.B.); (C.M.); (C.B.); (A.D.); (I.A.)
- Department of Psychological, Health and Territorial Sciences, “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy
| | - Ilaria Angilletta
- Center for Advanced Studies and Technology (CAST), “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy; (A.B.); (C.M.); (C.B.); (A.D.); (I.A.)
- Department of Psychological, Health and Territorial Sciences, “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy
| | - Marco Gatta
- Center for Advanced Studies and Technology (CAST), “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy; (A.B.); (C.M.); (C.B.); (A.D.); (I.A.)
- Department of Innovative Technologies in Medicine & Dentistry, “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy
| | - Patrizia Ballerini
- Center for Advanced Studies and Technology (CAST), “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy; (A.B.); (C.M.); (C.B.); (A.D.); (I.A.)
- Department of Innovative Technologies in Medicine & Dentistry, “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy
| | - Ivana Antonucci
- Center for Advanced Studies and Technology (CAST), “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy; (A.B.); (C.M.); (C.B.); (A.D.); (I.A.)
- Department of Psychological, Health and Territorial Sciences, “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy
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Bhallamudi S, Roos BB, Teske JJ, Wicher SA, McConico A, M Pabelick C, Sathish V, Prakash YS. Glial-derived neurotrophic factor in human airway smooth muscle. J Cell Physiol 2021; 236:8184-8196. [PMID: 34170009 DOI: 10.1002/jcp.30489] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 05/18/2021] [Accepted: 06/09/2021] [Indexed: 11/09/2022]
Abstract
Airway smooth muscle (ASM) cells modulate the local airway milieu via production of inflammatory mediators and growth factors including classical neurotrophins, such as brain-derived neurotrophic factor (BDNF). The glial cell-derived neurotrophic factor (GDNF) family of ligands (GFLs) are nonclassical neurotrophins and their role in the airway is barely understood. The major GFLs, GDNF and Neurturin (NRTN) bind to GDNF family receptor (GFR) α1 and α2 respectively that pair with Ret receptor to accomplish signaling. In this study, we found GDNF is expressed in human lung and increased in adult asthma, while human ASM expresses GDNF and its receptors. Accordingly, we used human ASM cells to test the hypothesis that ASM expression and autocrine signaling by GFLs regulate [Ca2+ ]i . Serum-deprived ASM cells from non-asthmatics were exposed to 10 ng/ml GDNF or NRTN for 15 min (acute) or 24 h (chronic). In fura-2 loaded cells, acute GDNF or NRTN alone induced [Ca2+ ]i responses, and further enhanced responses to 1 µM ACh or 10 µM histamine. Ret inhibitor (SPP86; 10 µM) or specific GDNF chelator GFRα1-Fc (1 µg/ml) showed roles of these receptors in GDNF effects. In contrast, NRTN did not enhance [Ca2+ ]i response to histamine. Furthermore, conditioned media of nonasthmatic and asthmatic ASM cells showed GDNF secretion. SPP86, Ret inhibitor and GFRα1-Fc chelator markedly decreased [Ca2+ ]i response compared with vehicle, highlighting autocrine effects of secreted GDNF. Chronic GDNF treatment increased histamine-induced myosin light chain phosphorylation. These novel data demonstrate GFLs particularly GDNF/GFRα1 influence ASM [Ca2+ ]i and raise the possibility that GFLs are potential targets of airway hyperresponsiveness.
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Affiliation(s)
- Sangeeta Bhallamudi
- Department of Pharmaceutical Sciences, North Dakota State University, Fargo, North Dakota, USA
| | - Benjamin B Roos
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Jacob J Teske
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Sarah A Wicher
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Andrea McConico
- Department of Pharmaceutical Sciences, North Dakota State University, Fargo, North Dakota, USA
| | - Christina M Pabelick
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, USA.,Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
| | - Venkatachalem Sathish
- Department of Pharmaceutical Sciences, North Dakota State University, Fargo, North Dakota, USA
| | - Y S Prakash
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, USA.,Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
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Marmolejo-Martínez-Artesero S, Casas C, Romeo-Guitart D. Endogenous Mechanisms of Neuroprotection: To Boost or Not to Boost. Cells 2021; 10:cells10020370. [PMID: 33578870 PMCID: PMC7916582 DOI: 10.3390/cells10020370] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 02/05/2021] [Accepted: 02/05/2021] [Indexed: 12/11/2022] Open
Abstract
Postmitotic cells, like neurons, must live through a lifetime. For this reason, organisms/cells have evolved with self-repair mechanisms that allow them to have a long life. The discovery workflow of neuroprotectors during the last years has focused on blocking the pathophysiological mechanisms that lead to neuronal loss in neurodegeneration. Unfortunately, only a few strategies from these studies were able to slow down or prevent neurodegeneration. There is compelling evidence demonstrating that endorsing the self-healing mechanisms that organisms/cells endogenously have, commonly referred to as cellular resilience, can arm neurons and promote their self-healing. Although enhancing these mechanisms has not yet received sufficient attention, these pathways open up new therapeutic avenues to prevent neuronal death and ameliorate neurodegeneration. Here, we highlight the main endogenous mechanisms of protection and describe their role in promoting neuron survival during neurodegeneration.
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Affiliation(s)
- Sara Marmolejo-Martínez-Artesero
- Department of Cell Biology, Physiology and Immunology, Institut de Neurociències (INc), Universitat Autònoma de Barcelona (UAB), Bellaterra, 08193 Barcelona, Spain;
| | - Caty Casas
- Department of Cell Biology, Physiology and Immunology, Institut de Neurociències (INc), Universitat Autònoma de Barcelona (UAB), Bellaterra, 08193 Barcelona, Spain;
| | - David Romeo-Guitart
- Department of Cell Biology, Physiology and Immunology, Institut de Neurociències (INc), Universitat Autònoma de Barcelona (UAB), Bellaterra, 08193 Barcelona, Spain;
- Laboratory “Hormonal Regulation of Brain Development and Functions”—Team 8, Institut Necker Enfants-Malades (INEM), INSERM U1151, Université Paris Descartes, Sorbonne Paris Cité, 75015 Paris, France
- Correspondence: ; Tel.: +33-01-40-61-53-57
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Hollville E, Romero SE, Deshmukh M. Apoptotic cell death regulation in neurons. FEBS J 2019; 286:3276-3298. [PMID: 31230407 DOI: 10.1111/febs.14970] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 05/15/2019] [Accepted: 06/20/2019] [Indexed: 12/16/2022]
Abstract
Apoptosis plays a major role in shaping the developing nervous system during embryogenesis as neuronal precursors differentiate to become post-mitotic neurons. However, once neurons are incorporated into functional circuits and become mature, they greatly restrict their capacity to die via apoptosis, thus allowing the mature nervous system to persist in a healthy and functional state throughout life. This robust restriction of the apoptotic pathway during neuronal differentiation and maturation is defined by multiple unique mechanisms that function to more precisely control and restrict the intrinsic apoptotic pathway. However, while these mechanisms are necessary for neuronal survival, mature neurons are still capable of activating the apoptotic pathway in certain pathological contexts. In this review, we highlight key mechanisms governing the survival of post-mitotic neurons, while also detailing the physiological and pathological contexts in which neurons are capable of overcoming this high apoptotic threshold.
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Affiliation(s)
| | - Selena E Romero
- Neuroscience Center, UNC Chapel Hill, NC, USA.,Department of Cell Biology and Physiology, UNC Chapel Hill, NC, 27599-7250, USA
| | - Mohanish Deshmukh
- Neuroscience Center, UNC Chapel Hill, NC, USA.,Department of Cell Biology and Physiology, UNC Chapel Hill, NC, 27599-7250, USA
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Sarveazad A, Janzadeh A, Taheripak G, Dameni S, Yousefifard M, Nasirinezhad F. Co-administration of human adipose-derived stem cells and low-level laser to alleviate neuropathic pain after experimental spinal cord injury. Stem Cell Res Ther 2019; 10:183. [PMID: 31234929 PMCID: PMC6591829 DOI: 10.1186/s13287-019-1269-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 05/15/2019] [Accepted: 05/16/2019] [Indexed: 12/20/2022] Open
Abstract
Background Evidence has suggested that human adipose-derived stem cells (hADSCs) and low-level laser has neuroprotective effects on spinal cord injury (SCI). Therefore, the combined effect of the hADSCs and laser on neuregeneration and neuropathic pain after SCI was investigated. Methods Forty-eight adult male Wistar rats with 200–250 g weight were used. Thirty minutes after compression, injury with laser was irritated, and 1 week following SCI, about 1 × 106 cells were transplanted into the spinal cord. Motor function and neuropathic pain were assessed weekly. Molecular and histological studies were done at the end of the fourth week. Results The combined application of hADSCs and laser has significantly improved motor function recovery (p = 0.0001), hyperalgesia (p < 0.05), and allodynia (p < 0.05). GDNF mRNA expression was significantly increased in hADSCs and laser+hADSC-treated animals (p < 0.001). Finally, co-administration of hADSCs and laser has enhanced the number of axons around cavity more than other treatments (p < 0.001). Conclusions The results showed that the combination of laser and ADSCs could significantly improve the motor function and alleviate SCI-induced allodynia and hyperalgesia. Therefore, using a combination of laser and hADSCs in future experimental and translational clinical studies is suggested.
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Affiliation(s)
- Arash Sarveazad
- Colorectal Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Atousa Janzadeh
- Radiation Biology Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Gholamreza Taheripak
- Department of Biochemistry, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Sima Dameni
- Physiology Research Center, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Mahmoud Yousefifard
- Physiology Research Center, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Farinaz Nasirinezhad
- Physiology Research Center and Department of Physiology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran. .,Department of Physiology, School of Medicine, Iran University of Medical Sciences, Hemmat Highway, Tehran, Iran.
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Upregulation of MicroRNA miR-9 Is Associated with Microcephaly and Zika Virus Infection in Mice. Mol Neurobiol 2018; 56:4072-4085. [DOI: 10.1007/s12035-018-1358-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 09/19/2018] [Indexed: 12/31/2022]
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Yun SE, Nam MK, Rhim H. Quantitative biochemical characterization and biotechnological production of caspase modulator, XIAP: Therapeutic implications for apoptosis-associated diseases. Biochim Biophys Acta Gen Subj 2018; 1862:1602-1611. [DOI: 10.1016/j.bbagen.2018.04.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 04/03/2018] [Accepted: 04/05/2018] [Indexed: 12/26/2022]
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Electrophysiological, Morphological, and Ultrastructural Features of the Injured Spinal Cord Tissue after Transplantation of Human Umbilical Cord Blood Mononuclear Cells Genetically Modified with the VEGF and GDNF Genes. Neural Plast 2017; 2017:9857918. [PMID: 28421147 PMCID: PMC5379091 DOI: 10.1155/2017/9857918] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Accepted: 01/24/2017] [Indexed: 01/12/2023] Open
Abstract
In this study, we examined the efficacy of human umbilical cord blood mononuclear cells (hUCB-MCs), genetically modified with the VEGF and GDNF genes using adenoviral vectors, on posttraumatic regeneration after transplantation into the site of spinal cord injury (SCI) in rats. Thirty days after SCI, followed by transplantation of nontransduced hUCB-MCs, we observed an improvement in H (latency period, LP) and M(Amax) waves, compared to the group without therapy after SCI. For genetically modified hUCB-MCs, there was improvement in Amax of M wave and LP of both the M and H waves. The ratio between Amax of the H and M waves (Hmax/Mmax) demonstrated that transplantation into the area of SCI of genetically modified hUCB-MCs was more effective than nontransduced hUCB-MCs. Spared tissue and myelinated fibers were increased at day 30 after SCI and transplantation of hUCB-MCs in the lateral and ventral funiculi 2.5 mm from the lesion epicenter. Transplantation of hUCB-MCs genetically modified with the VEGF and GNDF genes significantly increased the number of spared myelinated fibers (22-fold, P > 0.01) in the main corticospinal tract compared to the nontransduced ones. HNA+ cells with the morphology of phagocytes and microglia-like cells were found as compact clusters or cell bridges within the traumatic cavities that were lined by GFAP+ host astrocytes. Our results show that hUCB-MCs transplanted into the site of SCI improved regeneration and that hUCB-MCs genetically modified with the VEGF and GNDF genes were more effective than nontransduced hUCB-MCs.
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Spruill MM, Kuncl RW. Calbindin-D28K is increased in the ventral horn of spinal cord by neuroprotective factors for motor neurons. J Neurosci Res 2015; 93:1184-91. [PMID: 25914366 DOI: 10.1002/jnr.23562] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2014] [Revised: 11/27/2014] [Accepted: 01/01/2015] [Indexed: 02/06/2023]
Abstract
Slow glutamate-mediated neuronal degeneration is implicated in the pathophysiology of motor neuron diseases such as amyotrophic lateral sclerosis (ALS). The calcium-binding proteins calbindin-D28K and parvalbumin have been reported to protect neurons against excitotoxic insults. Expression of calbindin-D28K is low in adult human motor neurons, and vulnerable motor neurons additionally may lack parvalbumin. Thus, it has been speculated that the lack of calcium-binding proteins may, in part, be responsible for early degeneration of the population of motor neurons most vulnerable in ALS. Using a rat organotypic spinal cord slice system, we examined whether the most potent neuroprotective factors for motor neurons can increase the expression of calbindin-D28K or parvalbumin proteins in the postnatal spinal cord. After 4 weeks of incubation of spinal cord slices with 1) glial cell line-derived neurotrophic factor (GDNF), 2) neurturin, 3) insulin-like growth factor I (IGF-I), or 4) pigment epithelium-derived factor (PEDF), the number of calbindin-D28K -immunopositive large neurons (>20 μm) in the ventral horn was higher under the first three conditions, but not after PEDF, compared with untreated controls. Under the same conditions, parvalbumin was not upregulated by any neuroprotective factor. The same calbindin increase was true of IGF-I and GDNF in a parallel glutamate toxicity model of motor neuron degeneration. Taken together with our previous reports from the same model, which showed that all these neurotrophic factors can potently protect motor neurons from slow glutamate injury, the data here suggest that upregulation of calbindin-D28K by some of these factors may be one mechanism by which motor neurons can be protected from glutamate-induced, calcium-mediated excitotoxicity.
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Affiliation(s)
- Maria M Spruill
- Department of Neurology and Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Ralph W Kuncl
- Department of Neurology and Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland
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Fei D, Huang T, Krimm RF. The neurotrophin receptor p75 regulates gustatory axon branching and promotes innervation of the tongue during development. Neural Dev 2014; 9:15. [PMID: 24961238 PMCID: PMC4083039 DOI: 10.1186/1749-8104-9-15] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Accepted: 05/28/2014] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND Brain-derived neurotrophic factor (BDNF) and neurotrophin-4 (NT4) regulate the survival of gustatory neurons, axon growth and branching, and innervation of taste buds during development. These actions are largely, but not completely, mediated through the tyrosine kinase receptor, TrkB. Here, we investigated the role of p75, the other major receptor for BDNF and NT4, in the development of the taste system. RESULTS We found that p75-/-mice showed delayed axon outgrowth and reduced branching of gustatory axons at embryonic day (E)13.5. From E14.5 to E18.5, gustatory neurons innervated fewer papillae and completely failed to innervate the mid-region of the tongue in p75-/-mice. These early effects of the p75 mutation on gustatory axons preceded the loss of geniculate ganglion neurons starting at E14.5 and also contributed to a loss of taste buds at and after birth. Because knockouts for the TrkB receptor (TrkB-/-) do not lose as many taste buds as hybrid knockouts for its two ligands (BDNF and NT4), we asked if p75 maintains those additional taste buds in the absence of TrkB. It does not; hybrid TrkB-/-/p75-/-mice had more taste buds than TrkB-/-mice; these additional taste buds were not due to an increase in neurons or innervation. CONCLUSIONS p75 regulates gustatory neuron axon branching and tongue innervation patterns during taste system development. This function is likely accomplished independently of BDNF, NT4, and TrkB. In addition, p75 does not support the remaining neurons or taste buds in TrkB-/-mice.
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Affiliation(s)
| | | | - Robin F Krimm
- Department of Anatomical Sciences and Neurobiology, University of Louisville School of Medicine, Louisville, KY 40292, USA.
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Endogenous XIAP, but not other members of the inhibitory apoptosis protein family modulates cerebellar granule neurons survival. Int J Dev Neurosci 2014; 37:26-35. [PMID: 24955869 DOI: 10.1016/j.ijdevneu.2014.06.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Revised: 06/15/2014] [Accepted: 06/15/2014] [Indexed: 02/05/2023] Open
Abstract
Programmed cell death plays a critical role during cerebellar development. In particular, it has been shown in vivo and in vitro that developing cerebellar granule neurons (CGN) die apoptotically. Apoptosis involves a series of morphological changes and the activation of caspases. Inhibitor of apoptosis proteins (IAPs) is implicated in negative regulation of caspase activation and apoptotic cell death. Although apoptotic death of CGN has been extensively studied, there is no information about the role of IAPs in the developing cerebellum. Here, we studied the participation of some members of IAPs in the survival of the developing rat CGN in culture and under physiological conditions. Under these conditions, we found a differential expression pattern of cIAP-1, cIAP-2, XIAP and survivin during cerebellar development in an age-dependent manner, highlighting the significant increase of XIAP levels. We also detected an interaction between XIAP and caspase 3 at postnatal day (P) 12 and 16. On the other hand, we found a significant decrease of XIAP levels in cultured CGN maintained in chronic potassium deprivation, an apoptotic condition, suggesting a possible relationship between XIAP levels and neuronal viability. Under these conditions, we also detected the interaction of XIAP with active caspase-3. The down-regulation of XIAP in CGN cultured under survival conditions (chronic potassium depolarization) induced a reduction of cell viability and an increment of apoptotic cells. These findings support the idea that IAPs could be involved in the survival of CGN and that XIAP might be critical for neuronal survival in cerebellar development and during chronic depolarization in cultured CGN through a mechanism involving caspase inhibition.
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FAIM-L is an IAP-binding protein that inhibits XIAP ubiquitinylation and protects from Fas-induced apoptosis. J Neurosci 2014; 33:19262-75. [PMID: 24305822 DOI: 10.1523/jneurosci.2479-13.2013] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The neuronal long isoform of Fas Apoptotic Inhibitory Molecule (FAIM-L) protects from death receptor (DR)-induced apoptosis, yet its mechanism of protection remains unknown. Here, we show that FAIM-L protects rat neuronal Type II cells from Fas-induced apoptosis. XIAP has previously emerged as a molecular discriminator that is upregulated in Type II and downregulated in Type I apoptotic signaling. We demonstrate that FAIM-L requires sustained endogenous levels of XIAP to protect Type II cells as well as murine cortical neurons from Fas-induced apoptosis. FAIM-L interacts with the BIR2 domain of XIAP through an IAP-binding motif, the mutation of which impairs the antiapoptotic function of FAIM-L. Finally, we report that FAIM-L inhibits XIAP auto-ubiquitinylation and maintains its stability, thus conferring protection from apoptosis. Our results bring new understanding of the regulation of endogenous XIAP by a DR antagonist, pointing out at FAIM-L as a promising therapeutic tool for protection from apoptosis in pathological situations where XIAP levels are decreased.
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Sassa T. The Role of Human-Specific Gene Duplications During Brain Development and Evolution. J Neurogenet 2013; 27:86-96. [DOI: 10.3109/01677063.2013.789512] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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A novel growth-promoting pathway formed by GDNF-overexpressing Schwann cells promotes propriospinal axonal regeneration, synapse formation, and partial recovery of function after spinal cord injury. J Neurosci 2013; 33:5655-67. [PMID: 23536080 DOI: 10.1523/jneurosci.2973-12.2013] [Citation(s) in RCA: 95] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Descending propriospinal neurons (DPSN) are known to establish functional relays for supraspinal signals, and they display a greater growth response after injury than do the long projecting axons. However, their regenerative response is still deficient due to their failure to depart from growth supportive cellular transplants back into the host spinal cord, which contains numerous impediments to axon growth. Here we report the construction of a continuous growth-promoting pathway in adult rats, formed by grafted Schwann cells overexpressing glial cell line-derived neurotrophic factor (GDNF). We demonstrate that such a growth-promoting pathway, extending from the axonal cut ends to the site of innervation in the distal spinal cord, promoted regeneration of DPSN axons through and beyond the lesion gap of a spinal cord hemisection. Within the distal host spinal cord, regenerated DPSN axons formed synapses with host neurons leading to the restoration of action potentials and partial recovery of function.
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Pastor D, Viso-León MC, Botella-López A, Jaramillo-Merchan J, Moraleda JM, Jones J, Martínez S. Bone marrow transplantation in hindlimb muscles of motoneuron degenerative mice reduces neuronal death and improves motor function. Stem Cells Dev 2013; 22:1633-44. [PMID: 23282201 DOI: 10.1089/scd.2012.0487] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Bone marrow has proved to be an adequate source of stem cells for the treatment of numerous disorders, including neurodegenerative diseases. Bone marrow can be easily and relatively painlessly extracted from a patient or allogenic donor and then transplanted into the degenerative area. Here, the grafted cells will activate a number of mechanisms in order to protect, repair, and/or regenerate the damaged tissue. These properties make the bone marrow a feasible source for cell therapy. In this work, we transplanted bone marrow cells into a mouse model of motoneuron degeneration, with the particularity of placing the cells in the hindlimb muscles rather than in the spinal cord where neuronal degeneration occurs. To this end, we analyze the possibility for the transplanted cells to increase the survival rate of the spinal cord motoneurons by axonal-guided retrograde neurotrophism. As a result, the mice significantly improved their motor functions. This coincided with an increased number of motoneurons innervating the treated muscle compared with the neurons innervating the non-treated contralateral symmetric muscle. In addition, we detected an increase in glial-derived neurotrophic factor in the spinal cord, a neurotrophic factor known to be involved in the rescue of degenerating motoneurons, exerting a neuroprotective effect. Thus, we have proved that bone marrow injected into the muscles is capable of rescuing these motoneurons from death, which may be a possible therapeutic approach for spinal cord motoneuron degenerative diseases, such as amyotrophic lateral sclerosis.
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Affiliation(s)
- Diego Pastor
- Sports Science Research Center, Miguel Hernández University, Elche, Alicante 03202, Spain.
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Awad BI, Carmody MA, Steinmetz MP. Potential role of growth factors in the management of spinal cord injury. World Neurosurg 2013; 83:120-31. [PMID: 23334003 DOI: 10.1016/j.wneu.2013.01.042] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Revised: 01/06/2013] [Accepted: 01/11/2013] [Indexed: 12/31/2022]
Abstract
OBJECTIVE To review central nervous system growth factors and their therapeutic potential and clinical translation into spinal cord injury (SCI), as well as the challenges that have been encountered during clinical development. METHODS A systemic review of the available current and historical literature regarding central nervous system growth factors and clinical trials regarding their use in spinal cord injury was conducted. RESULTS The effectiveness of administering growth factors as a potential therapeutic strategy for SCI has been tested with the use of brain-derived neurotrophic factor, glial cell-derived neurotrophic factor, neurotrophin 3, and neurotrophin-4/5. Delivery of growth factors to injured SC has been tested by numerous methods. Unfortunately, most of clinical trials at this time are uncontrolled and have questionable results because of lack of efficacy and/or unacceptable side effects. CONCLUSIONS There is promise in the use of specific growth factors therapeutically for SCI. However, more studies involving neuronal regeneration and functional recovery are needed, as well the development of delivery methods that allow sufficient quantity of growth factors while restricting their distribution to target sites.
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Affiliation(s)
- Basem I Awad
- Department of Neurosurgery, Mansoura University School of Medicine, Mansoura, Egypt; Department of Neurosciences, MetroHealth Medical Center, Cleveland, Ohio, USA
| | - Margaret A Carmody
- Department of Neurosurgery, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA
| | - Michael P Steinmetz
- Department of Neurosciences, MetroHealth Medical Center, Cleveland, Ohio, USA.
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Kanno T, Tanaka K, Yanagisawa Y, Yasutake K, Hadano S, Yoshii F, Hirayama N, Ikeda JE. A novel small molecule, N-(4-(2-pyridyl)(1,3-thiazol-2-yl))-2-(2,4,6-trimethylphenoxy) acetamide, selectively protects against oxidative stress-induced cell death by activating the Nrf2-ARE pathway: therapeutic implications for ALS. Free Radic Biol Med 2012; 53:2028-42. [PMID: 23000247 DOI: 10.1016/j.freeradbiomed.2012.09.010] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Revised: 08/04/2012] [Accepted: 09/13/2012] [Indexed: 12/30/2022]
Abstract
Antioxidant defense is crucial in restoring cellular redox homeostasis. Recent findings have suggested that oxidative stress plays pivotal roles in the pathogenesis of many neurodegenerative diseases. Thus, an anti-oxidative stress remedy might be a promising means for the treatment of such disorders. In this study, we employed a novel ligand-based virtual screening system and identified a novel small molecule, N-(4-(2-pyridyl)(1,3-thiazol-2-yl))-2-(2,4,6-trimethylphenoxy) acetamide (CPN-9), which selectively suppressed oxidative stress-induced cell death in a cell-type-independent manner. CPN-9 upregulates NF-E2-related factor 2 (Nrf2), a key transcriptional regulator of the expression of phase II detoxification enzymes and antioxidant proteins, and Nrf2-regulated factors such as heme oxygenase-1 (HO-1), NAD(P)H quinone oxidoreductase 1 (NQO1), and glutamate-cysteine ligase modifier subunit (GCLM). The CPN-9-mediated upregulation of HO-1, NQO1, and GCLM was abolished by Nrf2 knockdown. Moreover, the antioxidant N-acetylcysteine reduced the protective effect of CPN-9 against oxidative stress-induced cell death with concomitant diminishing of Nrf2 nuclear translocation. These results indicate that CPN-9 exerts its activity via the reactive oxygen species-dependent activation of the Nrf2 signaling pathway in cultured cells. It is noteworthy that the postonset systemic administration of CPN-9 to a transgenic ALS mouse model carrying the H46R mutation in the human Cu/Zn superoxide dismutase (SOD1) gene sustained motor functions and delayed disease progression after onset. Collectively, CPN-9 is a novel Nrf2 activator and a neuroprotective candidate for the treatment of neurodegenerative diseases, including ALS.
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Affiliation(s)
- Takuya Kanno
- NGP Biomedical Research Institute, Neugen Pharma Inc., Kitasato University School of Medicine, Sagamihara, Kanagawa 252-0374, Japan
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18
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Gould TW, Oppenheim RW. Motor neuron trophic factors: therapeutic use in ALS? BRAIN RESEARCH REVIEWS 2011; 67:1-39. [PMID: 20971133 PMCID: PMC3109102 DOI: 10.1016/j.brainresrev.2010.10.003] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2010] [Revised: 10/12/2010] [Accepted: 10/18/2010] [Indexed: 12/12/2022]
Abstract
The modest effects of neurotrophic factor (NTF) treatment on lifespan in both animal models and clinical studies of Amyotropic Lateral Sclerosis (ALS) may result from any one or combination of the four following explanations: 1.) NTFs block cell death in some physiological contexts but not in ALS; 2.) NTFs do not rescue motoneurons (MNs) from death in any physiological context; 3.) NTFs block cell death in ALS but to no avail; and 4.) NTFs are physiologically effective but limited by pharmacokinetic constraints. The object of this review is to critically evaluate the role of both NTFs and the intracellular cell death pathway itself in regulating the survival of spinal and cranial (lower) MNs during development, after injury and in response to disease. Because the role of molecules mediating MN survival has been most clearly resolved by the in vivo analysis of genetically engineered mice, this review will focus on studies of such mice expressing reporter, null or other mutant alleles of NTFs, NTF receptors, cell death or ALS-associated genes.
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Affiliation(s)
- Thomas W Gould
- Department of Neurobiology and Anatomy, Wake Forest University School of Medicine, Winston-Salem, NC 27157-1010, USA.
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19
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Sun JY, Tseng H, Xu L, Hunter Z, Ciccarelli B, Fulciniti M, Zhu B, Maghsoudi K, Yang G, Gong P, Zhou Y, Liu X, Munshi NC, Patterson CJ, Treon SP. Vorinostat induced cellular stress disrupts the p38 mitogen activated protein kinase and extracellular signal regulated kinase pathways leading to apoptosis in Waldenström macroglobulinemia cells. Leuk Lymphoma 2011; 52:1777-86. [DOI: 10.3109/10428194.2011.577850] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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20
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Deng LX, Hu J, Liu N, Wang X, Smith GM, Wen X, Xu XM. GDNF modifies reactive astrogliosis allowing robust axonal regeneration through Schwann cell-seeded guidance channels after spinal cord injury. Exp Neurol 2011; 229:238-50. [PMID: 21316362 DOI: 10.1016/j.expneurol.2011.02.001] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2010] [Revised: 01/28/2011] [Accepted: 02/03/2011] [Indexed: 01/19/2023]
Abstract
Reactive astrogliosis impedes axonal regeneration after injuries to the mammalian central nervous system (CNS). Here we report that glial cell line-derived neurotrophic factor (GDNF), combined with transplanted Schwann cells (SCs), effectively reversed the inhibitory properties of astrocytes at graft-host interfaces allowing robust axonal regeneration, concomitant with vigorous migration of host astrocytes into SC-seeded semi-permeable guidance channels implanted into a right-sided spinal cord hemisection at the 10th thoracic (T10) level. Within the graft, migrated host astrocytes were in close association with regenerated axons. Astrocyte processes extended parallel to the axons, implying that the migrated astrocytes were not inhibitory and might have promoted directional growth of regenerated axons. In vitro, GDNF induced migration of SCs and astrocytes toward each other in an astrocyte-SC confrontation assay. GDNF also enhanced migration of astrocytes on a SC monolayer in an inverted coverslip migration assay, suggesting that this effect is mediated by direct cell-cell contact between the two cell types. Morphologically, GDNF administration reduced astrocyte hypertrophy and induced elongated process extension of these cells, similar to what was observed in vivo. Notably, GDNF treatment significantly reduced production of glial fibrillary acidic protein (GFAP) and chondroitin sulfate proteoglycans (CSPGs), two hallmarks of astrogliosis, in both the in vivo and in vitro models. Thus, our study demonstrates a novel role of GDNF in modifying spinal cord injury (SCI)-induced astrogliosis resulting in robust axonal regeneration in adult rats.
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Affiliation(s)
- Ling-Xiao Deng
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA
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21
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Wang J, Stern PH. Dose-dependent differential effects of risedronate on gene expression in osteoblasts. Biochem Pharmacol 2011; 81:1036-42. [PMID: 21300031 DOI: 10.1016/j.bcp.2011.01.025] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2011] [Revised: 01/26/2011] [Accepted: 01/31/2011] [Indexed: 11/18/2022]
Abstract
Bisphosphonates have multiple effects on bone. Their actions on osteoclasts lead to inhibition of bone resorption, at least partially through apoptosis. Effects on osteoblasts vary, with modifications in the molecule and concentration both resulting in qualitatively different responses. To understand the mechanism of the differential effects of high and low bisphosphonate concentrations on osteoblast activity, we compared the effects of 10⁻⁸ M and 10⁻⁴ M risedronate on gene expression in UMR-106 rat osteoblastic cells. Two targeted arrays, an 84-gene signaling array and an 84-gene osteogeneic array were used. Gene expression was measured at 1 and 24 h. Although some genes were regulated similarly by low and high concentrations of the drug, there was also differential regulation. At 1 h, 11 genes (1 signaling and 10 osteogenesis) were solely regulated by the low concentration, and 7 genes (3 signaling, 4 osteogenesis) were solely regulated by the high concentration. At 24 h, 8 genes (3 signaling, 5 osteogenesis) were solely regulated by the low concentration and 30 genes (16 signaling and 14 osteogenesis) were solely regulated by the high concentration. Interestingly, the low, but not the high concentration of risedronate transiently and selectively upregulated several genes associated with cell differentiation. A number of genes related to apoptosis were regulated, and could be involved in effects of bisphosphonates to promote osteoblast apoptosis. Also, observed gene changes associated with decreased angiogenesis and decreased metastasis could, if they occur in other cell types, provide a basis for the effectiveness of bisphosphonates in the prevention of cancer metastases.
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Affiliation(s)
- J Wang
- Department of Molecular Pharmacology and Biological Chemistry, Northwestern University Feinberg School of Medicine. 303 E. Chicago Ave., Chicago, IL 60611, USA
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Baratchi S, Kanwar RK, Kanwar JR. Novel survivin mutant protects differentiated SK-N-SH human neuroblastoma cells from activated T-cell neurotoxicity. J Neuroimmunol 2010; 233:18-28. [PMID: 21129784 DOI: 10.1016/j.jneuroim.2010.10.036] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2010] [Revised: 10/27/2010] [Accepted: 10/29/2010] [Indexed: 01/08/2023]
Abstract
Currently, there are no known treatments for protection of axonal loss associated with neuroinflammatory diseases such as multiple sclerosis (MS). Survivin is a member of the inhibitors of the apoptosis (IAP) family of proteins that its neuroprotective effects have not been studied. We demonstrate here that SurR9-C84A, a survivin mutant, exhibits a neuroprotective role against the cytotoxic effects of activated T-cell infiltrates, such as granzyme B (GrB). The activated T-cell supernatants induce toxicity on differentiated SK-N-SH cells, which is associated with the loss of Ca(2+) homeostasis, the increased population of dead cells, mitochondrial membrane depolarisation, and the accelerated expression of cyclinD1, caspase3 and Fas, as observed for most apoptotic cells. Alternatively, the pre-treatment with SurR9-C84A reduces the population of dead cells by balancing the cytosolic Ca(2+) homeostasis, decreasing the level of mitochondrial depolarisation, and also reducing the expression of cyclinD1 and caspase3. Our findings suggest that SurR9-C84A has a neuroprotective effect against the cytotoxins existing in activated T-cell supernatants including GrB.
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Affiliation(s)
- Sara Baratchi
- Laboratory of Immunology and Molecular Biomedical Research, Centre for Biotechnology and Interdisciplinary Biosciences (BioDeakin), Institute for Technology Research and Innovation (ITRI), Deakin University, Waurn Ponds, Victoria 3217, Australia
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Baratchi S, Kanwar RK, Kanwar JR. Survivin: A target from brain cancer to neurodegenerative disease. Crit Rev Biochem Mol Biol 2010; 45:535-54. [DOI: 10.3109/10409238.2010.516740] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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25
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Jiménez-Lara AM, Aranda A, Gronemeyer H. Retinoic acid protects human breast cancer cells against etoposide-induced apoptosis by NF-kappaB-dependent but cIAP2-independent mechanisms. Mol Cancer 2010; 9:15. [PMID: 20102612 PMCID: PMC2825243 DOI: 10.1186/1476-4598-9-15] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2009] [Accepted: 01/26/2010] [Indexed: 11/10/2022] Open
Abstract
Background Retinoids, through their cognate nuclear receptors, exert potent effects on cell growth, differentiation and apoptosis, and have significant promise for cancer therapy and chemoprevention. These ligands can determine the ultimate fate of target cells by stimulating or repressing gene expression directly, or indirectly through crosstalking with other signal transducers. Results Using different breast cancer cell models, we show here that depending on the cellular context retinoids can signal either towards cell death or cell survival. Indeed, retinoids can induce the expression of pro-apoptotic (i.e. TRAIL, TNF-Related Apoptosis-Inducing Ligand, Apo2L/TNFSF10) and anti-apoptotic (i.e. cIAP2, inhibitor of apoptosis protein-2) genes. Promoter mapping, gel retardation and chromatin immunoprecipitation assays revealed that retinoids induce the expression of this gene mainly through crosstalk with NF-kappaB. Supporting this crosstalk, the activation of NF-kappaB by retinoids in T47D cells antagonizes the apoptosis triggered by the chemotherapeutic drugs etoposide, camptothecin or doxorubicin. Notably apoptosis induced by death ligands (i.e. TRAIL or antiFAS) is not antagonized by retinoids. That knockdown of cIAP2 expression by small interfering RNA does not alter the inhibition of etoposide-induced apoptosis by retinoids in T47D cells reveals that stimulation of cIAP2 expression is not the cause of their anti-apoptotic action. However, ectopic overexpression of a NF-kappaB repressor increases apoptosis by retinoids moderately and abrogates almost completely the retinoid-dependent inhibition of etoposide-induced apoptosis. Our data exclude cIAP2 and suggest that retinoids target other regulator(s) of the NF-kappaB signaling pathway to induce resistance to etoposide on certain breast cancer cells. Conclusions This study shows an important role for the NF-kappaB pathway in retinoic acid signaling and retinoic acid-mediated resistance to cancer therapy-mediated apoptosis in breast cancer cells, independently of cIAP2. Our data support the use of NF-kappaB pathway activation as a marker for screening that will help to develop novel retinoids, or retinoid-based combination therapies with improved efficacy.
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Affiliation(s)
- Ana M Jiménez-Lara
- Instituto de Investigaciones Biomédicas de Madrid Alberto Sols, CSIC/UAM, Madrid, Spain.
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26
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Kairisalo M, Korhonen L, Sepp M, Pruunsild P, Kukkonen JP, Kivinen J, Timmusk T, Blomgren K, Lindholm D. NF-kappaB-dependent regulation of brain-derived neurotrophic factor in hippocampal neurons by X-linked inhibitor of apoptosis protein. Eur J Neurosci 2009; 30:958-66. [PMID: 19735291 DOI: 10.1111/j.1460-9568.2009.06898.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
X chromosome-linked inhibitor of apoptosis protein (XIAP) is an anti-apoptotic protein enhancing cell survival. Brain-derived neurotrophic factor (BDNF) also promotes neuronal viability but the links between XIAP and BDNF have remained unclear. We show here that the overexpression of XIAP increases BDNF in transgenic mice and cultured rat hippocampal neurons, whereas downregulation of XIAP by silencing RNA decreased BDNF. XIAP also stimulated BDNF signaling, as shown by increased phosphorylation of the TrkB receptor and the downstream molecule, cAMP response element-binding protein. The mechanism involved nuclear factor-kappaB (NF-kappaB) activation and blocking of NF-kappaB signaling inhibited the increased activities of BDNF promoters I and IV by XIAP. In neuronal cultures XIAP also upregulated interleukin (IL)-6, which is an NF-kappaB-responsive gene. The addition of IL-6 elevated whereas incubation with IL-6-blocking antibodies reduced BDNF in the neurons. BDNF itself activated NF-kappaB in the neurons at higher concentrations. The data show that XIAP has trophic effects on hippocampal neurons by increasing BDNF and TrkB activity. The results reveal a cytokine network in the brain involving BDNF, IL-6 and XIAP interconnected via the NF-kappaB system.
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Affiliation(s)
- Minna Kairisalo
- Minerva Institute for Medical Research, Biomedicum-2, Helsinki, Finland
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27
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Polyglutamine-expanded androgen receptor truncation fragments activate a Bax-dependent apoptotic cascade mediated by DP5/Hrk. J Neurosci 2009; 29:1987-97. [PMID: 19228953 DOI: 10.1523/jneurosci.4072-08.2009] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Spinal and bulbar muscular atrophy (SBMA) is an inherited neuromuscular disorder caused by a polyglutamine (polyQ) repeat expansion in the androgen receptor (AR). PolyQ-AR neurotoxicity may involve generation of an N-terminal truncation fragment, as such peptides occur in SBMA patients and mouse models. To elucidate the basis of SBMA, we expressed N-terminal truncated AR in motor neuron-derived cells and primary cortical neurons. Accumulation of polyQ-AR truncation fragments in the cytosol resulted in neurodegeneration and apoptotic, caspase-dependent cell death. Using primary neurons from mice transgenic or deficient for apoptosis-related genes, we determined that polyQ-AR apoptotic activation is fully dependent on Bax. Jun N-terminal kinase (JNK) was required for apoptotic pathway activation through phosphorylation of c-Jun. Expression of polyQ-AR in DP5/Hrk null neurons yielded significant protection against apoptotic activation, but absence of Bim did not provide protection, apparently due to compensatory upregulation of DP5/Hrk or other BH3-only proteins. Misfolded AR protein in the cytosol thus initiates a cascade of events beginning with JNK and culminating in Bax-dependent, intrinsic pathway activation, mediated in part by DP5/Hrk. As apoptotic mediators are candidates for toxic fragment generation and other cellular processes linked to neuron dysfunction, delineation of the apoptotic activation pathway induced by polyQ-expanded AR may shed light on the pathogenic cascade in SBMA and other motor neuron diseases.
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Yang CR, Yu RK. Intracerebral transplantation of neural stem cells combined with trehalose ingestion alleviates pathology in a mouse model of Huntington's disease. J Neurosci Res 2009; 87:26-33. [PMID: 18683244 DOI: 10.1002/jnr.21817] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The present investigation examined the neuroprotective benefits for combined trehalose administration with C17.2 neural stem cell transplantation in a transgenic mouse model of Huntington's disease (HD), R6/2. C17.2 neural stem cells have the potential of differentiating into a neuronal phenotype in vitro and have been shown to be effective in the treatment of a variety of lysosomal lipid storage disorders in the nervous system. In this study, we transplanted these cells into the lateral ventricle of R6/2 transgenic mice in order to examine the efficacy of using these cells for correcting the accumulated polyglutamine storage materials in HD. To improve efficacy, animals were fed with a diet rich in trehalose, which has been shown to be beneficial to retard aggregate formation. The combined treatment strategy not only decreased ubiquitin-positive aggregation in striatum, alleviated polyglutamine aggregation formation, and reduced striatal volume, but also extended life span in the R6/2 animal model. Behavioral evaluation showed that the combination treatment improved motor function. Statistical analysis revealed that the combination treatment was more effective than treatment with trehalose alone on the basis of the above biochemical and behavioral criteria. This study provides a strong a basis for further developing an effective therapeutic strategy for HD.
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Affiliation(s)
- Chia-Ron Yang
- Institute of Molecular Medicine and Genetics, Medical College of Georgia, Augusta, Georgia 30912, USA
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Saavedra A, Baltazar G, Duarte EP. Driving GDNF expression: the green and the red traffic lights. Prog Neurobiol 2008; 86:186-215. [PMID: 18824211 DOI: 10.1016/j.pneurobio.2008.09.006] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2007] [Revised: 06/18/2008] [Accepted: 09/03/2008] [Indexed: 01/28/2023]
Abstract
Glial cell line-derived neurotrophic factor (GDNF) is widely recognized as a potent survival factor for dopaminergic neurons of the nigrostriatal pathway that degenerate in Parkinson's disease (PD). In animal models of PD, GDNF delivery to the striatum or the substantia nigra protects dopaminergic neurons against subsequent toxin-induced injury and rescues previously damaged neurons, promoting recovery of the motor function. Thus, GDNF was proposed as a potential therapy to PD aimed at slowing down, halting or reversing neurodegeneration, an issue addressed in previous reviews. However, the use of GDNF as a therapeutic agent for PD is hampered by the difficulty in delivering it to the brain. Another potential strategy is to stimulate the endogenous expression of GDNF, but in order to do that we need to understand how GDNF expression is regulated. The aim of this review is to do a comprehensive analysis of the state of the art on the control of endogenous GDNF expression in the nervous system, focusing mainly on the nigrostriatal pathway. We address the control of GDNF expression during development, in the adult brain and after injury, and how damaged neurons signal glial cells to up-regulate GDNF. Pharmacological agents or natural molecules that increase GDNF expression and show neuroprotective activity in animal models of PD are reviewed. We also provide an integrated overview of the signalling pathways linking receptors for these molecules to the induction of GDNF gene, which might also become targets for neuroprotective therapies in PD.
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Affiliation(s)
- Ana Saavedra
- Department of Cell Biology, Immunology and Neurosciences, Faculty of Medicine, University of Barcelona, Carrer Casanova 143, 08036 Barcelona, Spain.
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Pan Q, Liu B, Liu J, Cai R, Liu X, Qian C. Synergistic antitumor activity of XIAP-shRNA and TRAIL expressed by oncolytic adenoviruses in experimental HCC. Acta Oncol 2008; 47:135-44. [PMID: 17934893 DOI: 10.1080/02841860701403053] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
RNA interference (RNAi) induced by small interfering RNA (siRNA) can trigger sequence-specific gene silencing in mammalian cells. It has been proposed that siRNA can be developed as a novel strategy for cancer therapy. However effective delivery of therapeutically active siRNAs into the target tissue/cells in vivo is still a major obstacle for successful application. Oncolytic adenoviral vector mediated RNAi provides the potential advantages of minimizing the harm of normal cells, regenerating siRNAs within the tumor microenvironment and inspiring an additive antitumor outcome through viral oncolysis. Hepatocellular carcinoma (HCC) displays a high resistance to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-mediated cell death, partially due to high expression levels of the X-linked Inhibitor-of-Apoptosis protein (XIAP). Here, we utilized an oncolytic adenovirus (ZD55) for expressing short hairpin RNA (shRNA), a precursor of siRNA, to knockdown XIAP. To increase sensitivity of HCC cells to TRAIL, we have used ZD55 to deliver both XIAP-shRNA and TRAIL into HCC cells. The results showed that the combination of ZD55-XIAP-shRNA and ZD55-TRAIL resulted in significant reduction of XIAP expression and potent antitumor activity both in HCC cells and in animal model with tumor. This pilot study offers a promise of using oncolytic adenovirus to deliver siRNA targeting overexpressed oncogenes and a novel strategy for cancer therapy by regulating the equilibrium between the proapoptotic and antiapoptotic factors.
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Encinas M, Rozen EJ, Dolcet X, Jain S, Comella JX, Milbrandt J, Johnson EM. Analysis of Ret knockin mice reveals a critical role for IKKs, but not PI 3-K, in neurotrophic factor-induced survival of sympathetic neurons. Cell Death Differ 2008; 15:1510-21. [PMID: 18497757 DOI: 10.1038/cdd.2008.76] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
We analyzed the survival responses and downstream signaling elicited by GDNF on sympathetic neurons from different Ret knockin mice. Lack of tyrosine 1062, a multidocking site in Ret, completely prevented GDNF-mediated survival. Importantly, lack of tyrosine 981, although abrogating Akt phosphorylation, had no effect on neuronal survival, indicating that the PI 3-K/Akt pathway is not necessary for survival of sympathetic neurons. In contrast, silencing of B-Raf completely prevented not only GDNF-mediated but also NGF-mediated cell survival, independently of MEK-1/2. We identified IKKs as the main effectors of the protective effects of B-Raf. First, B-Raf interacted with and activated IKKs. Second, knockdown of IKKs reversed the protection afforded by a constitutively active form of B-Raf. Third, knockdown of IKKs prevented both NGF- and GDNF-mediated survival. In conclusion, our data delineate a novel survival pathway for sympathetic neurons linking B-Raf to IKKs, independently of both PI 3-K and MEK-1/2 pathways.
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Affiliation(s)
- M Encinas
- Cell Signaling and Apoptosis Group, Departament de Medicina Experimental, Lleida 25198, Spain.
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RET signaling does not modulate MPTP toxicity but is required for regeneration of dopaminergic axon terminals. Proc Natl Acad Sci U S A 2007; 104:20049-54. [PMID: 18056810 DOI: 10.1073/pnas.0706177104] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Activation of the RET (rearranged during transfection) receptor by glial cell-line-derived neurotrophic factor (GDNF) has been identified as an important differentiation and survival factor for dopaminergic neurons of the midbrain in preclinical experiments. These encouraging results have led to clinical trials of GDNF in patients with Parkinson's disease, which have resulted in conflicting findings. To investigate the potential benefit of Ret-dependent signaling on the challenged dopaminergic system, we tested the effect of tissue-selective ablation of the Ret gene on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) toxicity in mice, the most widely used animal model for Parkinson's disease. Ablation of Ret did not modify the MPTP-induced loss of dopaminergic neurons in the substantia nigra pars compacta and the dopaminergic innervation of the striatum at 14 days. However, Ret ablation abolished the regeneration of dopaminergic fibers and terminals, as well as the partial recovery of striatal dopamine concentrations, that was observed in control mice between days 14 and 90 after MPTP treatment. We therefore conclude that RET signaling has no influence on the survival of dopaminergic neurons in the MPTP model of Parkinson's disease but rather facilitates the regeneration of dopaminergic axon terminals.
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Frebel K, Wiese S, Funk N, Pühringer D, Sendtner M. Differential modulation of neurite growth by the S- and the L-forms of bag1, a co-chaperone of Hsp70. NEURODEGENER DIS 2007; 4:261-9. [PMID: 17596720 DOI: 10.1159/000101850] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Bag1 acts as a cochaperone for Hsp70. However, it also binds to members of the RAF family and to Akt. In addition, bag1 and Hsp70 are part of a complex with glucocorticoid receptors and thus modulate glucocorticoid receptor-mediated transcriptional activation. In the developing nervous system, bag1 is expressed in at least two isoforms. The L-form (bag1L) contains a nuclear localization signal and thus can translocate to the nucleus. In contrast, the S-form (bag1S) is localized exclusively in the cytoplasm. Former studies have shown that B-RAF is essential for neurotrophin-mediated survival signaling in motoneurons and sensory neurons, and that bag1 plays a role in coordinating B-RAF and Akt function in this context. In the absence of B-RAF, embryonic motoneurons and sensory neurons are not able to survive, indicating that bag1 and B-RAF are essential mediators for neuronal survival in response to neurotrophic factors during development. However, the role of the complex containing bag1, Hsp70 and B-RAF in mediating neurite growth in response to neurotrophic factors remained unclear. We have therefore studied the effect of bag1 overexpression in rat phaeochromocytoma (PC12) cells. Upon NGF treatment, proliferating PC12 become postmitotic and grow out neuronal processes. Bag1S overexpression interferes with neurite extension in PC12 cells. In contrast, bag1L does not disturb neurite outgrowth. Interaction of bag1S with Hsp70 appears necessary for this effect. These data indicate that the cytosolic form of bag1 participates in neurotrophin-mediated neurite growth, and that interaction with Hsp70 plays a crucial role in this context.
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Affiliation(s)
- Karin Frebel
- Institute for Clinical Neurobiology, University of Würzburg, Würzburg, Germany
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Suzuki M, McHugh J, Tork C, Shelley B, Klein SM, Aebischer P, Svendsen CN. GDNF secreting human neural progenitor cells protect dying motor neurons, but not their projection to muscle, in a rat model of familial ALS. PLoS One 2007; 2:e689. [PMID: 17668067 PMCID: PMC1925150 DOI: 10.1371/journal.pone.0000689] [Citation(s) in RCA: 220] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2007] [Accepted: 06/12/2007] [Indexed: 12/23/2022] Open
Abstract
Background Amyotrophic lateral sclerosis (ALS) is a fatal, progressive neurodegenerative disease characterized by rapid loss of muscle control and eventual paralysis due to the death of large motor neurons in the brain and spinal cord. Growth factors such as glial cell line derived neurotrophic factor (GDNF) are known to protect motor neurons from damage in a range of models. However, penetrance through the blood brain barrier and delivery to the spinal cord remains a serious challenge. Although there may be a primary dysfunction in the motor neuron itself, there is also increasing evidence that excitotoxicity due to glial dysfunction plays a crucial role in disease progression. Clearly it would be of great interest if wild type glial cells could ameliorate motor neuron loss in these models, perhaps in combination with the release of growth factors such as GDNF. Methodology/Principal Findings Human neural progenitor cells can be expanded in culture for long periods and survive transplantation into the adult rodent central nervous system, in some cases making large numbers of GFAP positive astrocytes. They can also be genetically modified to release GDNF (hNPCGDNF) and thus act as long-term ‘mini pumps’ in specific regions of the rodent and primate brain. In the current study we genetically modified human neural stem cells to release GDNF and transplanted them into the spinal cord of rats over-expressing mutant SOD1 (SOD1G93A). Following unilateral transplantation into the spinal cord of SOD1G93A rats there was robust cellular migration into degenerating areas, efficient delivery of GDNF and remarkable preservation of motor neurons at early and end stages of the disease within chimeric regions. The progenitors retained immature markers, and those not secreting GDNF had no effect on motor neuron survival. Interestingly, this robust motor neuron survival was not accompanied by continued innervation of muscle end plates and thus resulted in no improvement in ipsilateral limb use. Conclusions/Significance The potential to maintain dying motor neurons by delivering GDNF using neural progenitor cells represents a novel and powerful treatment strategy for ALS. While this approach represents a unique way to prevent motor neuron loss, our data also suggest that additional strategies may also be required for maintenance of neuromuscular connections and full functional recovery. However, simply maintaining motor neurons in patients would be the first step of a therapeutic advance for this devastating and incurable disease, while future strategies focus on the maintenance of the neuromuscular junction.
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Affiliation(s)
- Masatoshi Suzuki
- The Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Jacalyn McHugh
- The Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Craig Tork
- The Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Brandon Shelley
- The Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Sandra M. Klein
- The Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Patrick Aebischer
- Brain & Mind Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Clive N. Svendsen
- The Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Departments of Anatomy and Neurology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- * To whom correspondence should be addressed. E-mail:
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Müller GJ, Lassmann H, Johansen FF. Anti-apoptotic signaling and failure of apoptosis in the ischemic rat hippocampus. Neurobiol Dis 2007; 25:582-93. [PMID: 17207631 DOI: 10.1016/j.nbd.2006.11.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2006] [Revised: 10/03/2006] [Accepted: 11/03/2006] [Indexed: 11/18/2022] Open
Abstract
Several anti-apoptotic proteins are induced in CA1 neurons after transient forebrain ischemia (TFI), but fail to protect the majority of these cells from demise. Correlating cell death morphologies (apoptosis-like and necrosis-like death) with immunohistochemistry (IHC), we investigated whether anti-apoptosis contributes to survival, compromises apoptosis effector functions and/or delays death in CA1 neurons 1-7 days after TFI. As surrogate markers for bioenergetic failure, the IHC of respiratory chain complex (RCC) subunits was investigated. Dentate granule cell (DGC) apoptosis following colchicine injection severed as a reference for classical apoptosis. Heat shock protein 70 (Hsp70), neuronal apoptosis inhibitory protein (NAIP) and manganese superoxide dismutase (MnSOD) were upregulated in the majority of intact CA1 neurons paralleling the occurrence of CA1 neuronal death (days 3-7) as well as in a proportion of apoptosis-(<50%) and necrosis-like (<30%) CA1 neurons. Colchicine did not provoke an anti-apoptotic response in DGC at all. In addition, more than 70% of apoptosis- and necrosis-like CA1 neurons had completely lost their RCC subunits suggesting bioenergetic failure; by contrast, following colchicine injection, 88% of all apoptotic DGC presented RCC subunits. Thus, anti-apoptotic proteins may, in a subset of ischemic CA1 neurons, prevent cell death, while in others, affected by pronounced energy failure, they may cause secondary necrosis.
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Affiliation(s)
- Georg Johannes Müller
- Molecular Neuropathology Group, University of Copenhagen, 11, Frederik V's vej, 2100-Copenhagen-O, Denmark
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36
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Li Q, Li H, Blitvich BJ, Zhang J. The Aedes albopictus inhibitor of apoptosis 1 gene protects vertebrate cells from bluetongue virus-induced apoptosis. INSECT MOLECULAR BIOLOGY 2007; 16:93-105. [PMID: 17257212 DOI: 10.1111/j.1365-2583.2007.00705.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
We sequenced and characterized the inhibitor of apoptosis (iap) 1 gene from Aedes albopictus, designated as Aaiap1. The Aaiap1 gene rescued Spodoptera frugiperda (Sf9) cells from apoptosis when cotransfected with the Drosophila pro-apoptotic hid gene. The antiapoptotic function of the Aaiap1 gene was evaluated in the bluetongue virus (BTV)-induced apoptosis system. BTV infection induced apoptosis in vertebrate cells via the intrinsic apoptotic pathway. This was shown by the translocation of cytochrome C and the second mitochondria-derived activator of caspase (Smac, also known as DIABLO) from the mitochondria and the subsequent activation of caspase-9 and -3. Stable expression of the Aaiap1 gene in derivative baby hamster kidney cells delayed BTV-induced apoptosis by 24 h and reduced the BTV progeny yield by 10-fold. This study provides the first evidence that the mosquito AaIAP1 protein possesses antiapoptotic activity.
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Affiliation(s)
- Q Li
- Division of Geographic Medicine, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
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37
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Kells AP, Henry RA, Hughes SM, Connor B. Verification of functional AAV-mediated neurotrophic and anti-apoptotic factor expression. J Neurosci Methods 2006; 161:291-300. [PMID: 17178422 DOI: 10.1016/j.jneumeth.2006.11.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2006] [Revised: 11/09/2006] [Accepted: 11/10/2006] [Indexed: 12/29/2022]
Abstract
The use of viral vectors for gene delivery offer many advantages for both basic research and therapeutic application through the continuous expression of a gene product within a target region. It is vital however that any gene product is correctly expressed in a biologically active form, and this should be confirmed prior to large scale in vivo studies. Using adeno-associated viral (AAV) vectors to direct the expression of either a neurotrophic factor or an anti-apoptotic protein, we have developed a range of in vitro assays to verify functional transgenic protein expression. Brain-derived neurotropic factor (BDNF) activity was confirmed by demonstrating enhanced generation of GABAergic neurons in embryonic (E15) striatal cultures and AAV-mediated glial-derived neurotrophic factor (GDNF) function using an assay for dopaminergic differentiation of embryonic (E14) ventral mesencephalic cultures. To assess functional anti-apoptotic factor expression we designed cell-survival assays, using embryonic cortical cultures to confirm Bcl-x(L) activity and the HT1080 cell-line for X-linked inhibitor of apoptosis protein (XIAP) activity following AAV-mediated expression. This study demonstrates that the use of functional assays provides valuable confirmation of desired biotherapeutic expression prior to extensive investigation with new gene delivery vectors.
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Affiliation(s)
- Adrian P Kells
- Neural Repair and Neurogenesis Laboratory, Department of Pharmacology and Clinical Pharmacology, The University of Auckland, Auckland, New Zealand
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38
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Abstract
When subjected to excessive oxidative stress, neurons may respond adaptively to overcome the stress, or they may activate a programmed cell death pathway called apoptosis. Apoptosis is characterized by alterations in mitochondria and the endoplasmic reticulum and activation of cysteine proteases called caspases. Increasing evidence suggests that apoptotic biochemical cascades are involved in the dysfunction and death of neurons in neurodegenerative disorders such as Alzheimer's, Parkinson, and Huntington's diseases. Studies of normal aging, of genetic mutations that cause disease, and of environmental factors that affect disease risk are revealing cellular and molecular alterations that may cause excessive oxidative stress and trigger neuronal apoptosis. Accumulation of self-aggregating proteins such as amyloid beta-peptide, tau, alpha-synuclein, and huntingtin may be involved in apoptosis both upstream and downstream of oxidative stress. Membrane-associated oxidative stress resulting in perturbed lipid metabolism and disruption of cellular calcium homeostasis may trigger apoptosis in several different neurodegenerative disorders. Counteracting neurodegenerative processes are an array of mechanisms including neurotrophic factor signaling, antioxidant enzymes, protein chaperones, antiapoptotic proteins, and ionostatic systems. Emerging findings suggest that the resistance of neurons to death during aging can be enhanced by modifications of diet and lifestyle.
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Affiliation(s)
- Mark P Mattson
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, Maryland 21224, USA.
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Legewie S, Blüthgen N, Herzel H. Mathematical modeling identifies inhibitors of apoptosis as mediators of positive feedback and bistability. PLoS Comput Biol 2006; 2:e120. [PMID: 16978046 PMCID: PMC1570177 DOI: 10.1371/journal.pcbi.0020120] [Citation(s) in RCA: 163] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2006] [Accepted: 07/28/2006] [Indexed: 12/19/2022] Open
Abstract
The intrinsic, or mitochondrial, pathway of caspase activation is essential for apoptosis induction by various stimuli including cytotoxic stress. It depends on the cellular context, whether cytochrome c released from mitochondria induces caspase activation gradually or in an all-or-none fashion, and whether caspase activation irreversibly commits cells to apoptosis. By analyzing a quantitative kinetic model, we show that inhibition of caspase-3 (Casp3) and Casp9 by inhibitors of apoptosis (IAPs) results in an implicit positive feedback, since cleaved Casp3 augments its own activation by sequestering IAPs away from Casp9. We demonstrate that this positive feedback brings about bistability (i.e., all-or-none behaviour), and that it cooperates with Casp3-mediated feedback cleavage of Casp9 to generate irreversibility in caspase activation. Our calculations also unravel how cell-specific protein expression brings about the observed qualitative differences in caspase activation (gradual versus all-or-none and reversible versus irreversible). Finally, known regulators of the pathway are shown to efficiently shift the apoptotic threshold stimulus, suggesting that the bistable caspase cascade computes multiple inputs into an all-or-none caspase output. As cellular inhibitory proteins (e.g., IAPs) frequently inhibit consecutive intermediates in cellular signaling cascades (e.g., Casp3 and Casp9), the feedback mechanism described in this paper is likely to be a widespread principle on how cells achieve ultrasensitivity, bistability, and irreversibility.
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Affiliation(s)
- Stefan Legewie
- Institute for Theoretical Biology, Humboldt University, Berlin, Germany.
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40
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Kiryu-Seo S, Gamo K, Tachibana T, Tanaka K, Kiyama H. Unique anti-apoptotic activity of EAAC1 in injured motor neurons. EMBO J 2006; 25:3411-21. [PMID: 16858406 PMCID: PMC1523171 DOI: 10.1038/sj.emboj.7601225] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2006] [Accepted: 06/14/2006] [Indexed: 11/08/2022] Open
Abstract
Injured motor neurons of the adult rat can survive, whereas similar axotomy causes gradual motor neuron death in the adult mouse. We report that the decreased expression of the neuronal glutamate transporter excitatory amino-acid carrier 1 (EAAC1) following nerve injury is associated with motor neuron death in the mouse. Glutamate transporters play a crucial role in prevention of neuronal death by suppressing glutamate toxicity. However, the possible functional role of EAAC1 in preventing neuron death has not been resolved as compared with glial glutamate transporters such as GLT-1. Here, we have revealed a unique 'rescue' function of EAAC1, which is independent of removal of extracellular glutamate. During apoptotic stimuli, a mitochondrial protein, holocytochrome c synthetase (HCCS), translocates to outside the mitochondria, binds to and suppresses the X-linked inhibitor of apoptosis protein (XIAP), leading to activation of caspase-3. The N-terminus of EAAC1 can bind to HCCS, which interferes with the HCCS-XIAP association, and thereby maintain XIAP activity. This unique anti-apoptotic mechanism of EAAC1 functions in rescuing PC12 cells and motor neurons from NGF deprivation and nerve injury, respectively.
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Affiliation(s)
- Sumiko Kiryu-Seo
- Department of Anatomy and Neurobiology, Osaka City University, Graduate School of Medicine, Abeno-ku, Osaka, Japan
| | - Kazushige Gamo
- Department of Anatomy and Neurobiology, Osaka City University, Graduate School of Medicine, Abeno-ku, Osaka, Japan
| | - Taro Tachibana
- Department of Applied and Bioapplied Chemistry, Graduate School of Engineering, Osaka City University, Sumiyoshi-ku, Osaka, Japan
| | - Kohichi Tanaka
- Laboratory of Molecular Neuroscience, School of Biomedical Science and Medical Research Institute, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo, Japan
| | - Hiroshi Kiyama
- Department of Anatomy and Neurobiology, Osaka City University, Graduate School of Medicine, Abeno-ku, Osaka, Japan
- Department of Anatomy and Neurobiology, Osaka City University, Graduate School of Medicine, 1-4-3 Asahimachi, Abeno-ku, Osaka 545-8585, Japan. Tel.: +81 6 6645 3701; Fax: +81 6 6645 3702; E-mail:
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41
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Kobori N, Moore AN, Dash PK. GDNF abates serum deprivation-induced tyrosine hydroxylase Ser19 phosphorylation and activity. Brain Res 2006; 1086:142-51. [PMID: 16626642 DOI: 10.1016/j.brainres.2006.02.111] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2005] [Revised: 01/20/2006] [Accepted: 02/26/2006] [Indexed: 10/24/2022]
Abstract
High dopamine levels can contribute to neuronal dysfunction, impair plasticity and be toxic to neuronal cells in pathological conditions. The synthesis of dopamine is regulated by phosphorylation of the rate-limiting enzyme tyrosine hydroxylase (TH) under physiological conditions, with the phosphorylation of Ser31 and Ser40 directly increasing TH activity. Although a third phosphorylation site, Ser19, does not appear to directly regulate TH activity in physiological conditions, its role in pathological conditions is poorly understood. In this study, we examined the effects of serum deprivation (to mimic loss of retrogradely/anterogradely transported target-derived neurotrophic factors following axonal injury) and glutamate receptor stimulation (to mimic excitotoxicity) on TH phosphorylation and activity in a cell line and in mesencephalic primary culture cells. In addition, we also tested whether glial cell line-derived neurotrophic factor (GDNF) can alter these changes. We demonstrate that serum-deprivation resulted in a sustained increase in Ser19 phosphorylation beginning at 3 h and lasting up to 10 h without any detectable change in Ser31 or Ser40 phosphorylation within this time frame. This increase in Ser19 phosphorylation was associated with enhanced TH activity and was due, in part, to glutamate-receptor-mediated calcium influx and possibly calcium/calmodulin-dependent protein kinase II (CaMKII) activation. Interestingly in this serum-deprivation model, GDNF blocked the increase in Ser19 phosphorylation and TH activity at the 10-h time point following serum deprivation. Furthermore, GDNF also blocked the glutamate-mediated increase in Ser19 phosphorylation in rat primary mesencephalic neuronal cultures. Taken together, these findings suggest that GDNF may reduce dopamine synthesis in pathological conditions.
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Affiliation(s)
- Nobuhide Kobori
- Department of Neurobiology and Anatomy, The Vivian L. Smith Center for Neurological Research, The University of Texas Medical School, PO Box 20708, Houston, 77255, USA
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Nakamura TY, Jeromin A, Smith G, Kurushima H, Koga H, Nakabeppu Y, Wakabayashi S, Nabekura J. Novel role of neuronal Ca2+ sensor-1 as a survival factor up-regulated in injured neurons. ACTA ACUST UNITED AC 2006; 172:1081-91. [PMID: 16549499 PMCID: PMC2063765 DOI: 10.1083/jcb.200508156] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A molecular basis of survival from neuronal injury is essential for the development of therapeutic strategy to remedy neurodegenerative disorders. In this study, we demonstrate that an EF-hand Ca2+-binding protein neuronal Ca2+ sensor-1 (NCS-1), one of the key proteins for various neuronal functions, also acts as an important survival factor. Overexpression of NCS-1 rendered cultured neurons more tolerant to cell death caused by several kinds of stressors, whereas the dominant-negative mutant (E120Q) accelerated it. In addition, NCS-1 proteins increased upon treatment with glial cell line-derived neurotrophic factor (GDNF) and mediated GDNF survival signal in an Akt (but not MAPK)-dependent manner. Furthermore, NCS-1 is significantly up-regulated in response to axotomy-induced injury in the dorsal motor nucleus of the vagus neurons of adult rats in vivo, and adenoviral overexpression of E120Q resulted in a significant loss of surviving neurons, suggesting that NCS-1 is involved in an antiapoptotic mechanism in adult motor neurons. We propose that NCS-1 is a novel survival-promoting factor up-regulated in injured neurons that mediates the GDNF survival signal via the phosphatidylinositol 3-kinase-Akt pathway.
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Affiliation(s)
- Tomoe Y Nakamura
- Department of Molecular Physiology, National Cardiovascular Center Research Institute, Suita, Osaka 565-8565, Japan.
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Plesner A, Liston P, Tan R, Korneluk RG, Verchere CB. The X-linked inhibitor of apoptosis protein enhances survival of murine islet allografts. Diabetes 2005; 54:2533-40. [PMID: 16123340 DOI: 10.2337/diabetes.54.9.2533] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Allotransplantation of pancreatic islets represents a promising approach to treat type 1 diabetes. Destruction of beta-cells in islet allografts involves multiple immune mechanisms that lead to activation of caspases and apoptotic cell death. The X-linked inhibitor of apoptosis (XIAP) inhibits apoptosis induced by a variety of triggers, primarily by preventing the activation of caspases. To determine whether XIAP would protect beta-cells from apoptosis, we used a recombinant adenovirus to overexpress XIAP in transformed murine beta-cells and in freshly isolated islets. In vitro cytokine-induced beta-cell death was decreased to baseline levels in XIAP-transduced MIN-6 and NIT-1 cell lines compared with controls. To evaluate the potential of XIAP overexpression to prevent in vivo allogeneic graft rejection, we transduced Balb/c islets ex vivo with XIAP before transplantation into CBA mice with streptozotocin-induced diabetes. We observed that almost all mice receiving allografts of XIAP-expressing islets maintained normoglycemia until the experiment was terminated (45-72 days posttransplant), whereas control mice receiving islets transduced with adenovirus expressing LacZ were hyperglycemic by approximately 17 days posttransplantation due to graft rejection. Immunohistochemistry revealed preservation of beta-cells and clearance of infiltrating immune cells in the XIAP-expressing islet grafts. The in vitro allogeneic response of splenocytes isolated from recipients of XIAP-expressing grafts 8 weeks posttransplant was similar to that seen in nonprimed allogeneic mice, suggesting that XIAP overexpression may lead to the acceptance of islet allografts in diabetic recipients. Long-term protection of islet allografts by XIAP overexpression may enhance the survival of islet transplants in diabetes.
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Affiliation(s)
- Annette Plesner
- BC Research Institute for Children's and Women's Health, University of British Columbia, Department of Pathology and Laboratory Medicine, Room 2071-950, W. 28th Ave., Vancouver, British Columbia, V5Z 4H4, Canada.
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Okada Y, Sakai H, Kohiki E, Suga E, Yanagisawa Y, Tanaka K, Hadano S, Osuga H, Ikeda JE. A dopamine D4 receptor antagonist attenuates ischemia-induced neuronal cell damage via upregulation of neuronal apoptosis inhibitory protein. J Cereb Blood Flow Metab 2005; 25:794-806. [PMID: 15729293 DOI: 10.1038/sj.jcbfm.9600078] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Neuronal apoptosis inhibitory protein (NAIP/BIRC1), the inhibitor of apoptosis protein (IAP) family member, suppresses neuronal cell death induced by a variety of insults, including cell death from ischemia and stroke. The goal of the present study was to develop an efficient method for identification of compounds with the ability to upregulate endogenous NAIP and to determine the effects on these compounds on the cellular response to ischemia. A novel NAIP-enzyme-linked immunosorbent assay (ELISA)-based in vitro drug-screening system is established. Use of this system identified an antagonist of dopamine D4 receptor, termed L-745,870, with a potent NAIP upregulatory effect. L-745,870-mediated NAIP upregulation in neuronal and nonneuronal cultured cells resulted in decreased vulnerability to oxidative stress-induced apoptosis. Reducing NAIP expression via RNA interference techniques resulted in prevention of L-745,870-mediated protection from oxidative stress. Further, systemic administration of L-745,870 attenuated ischemia-induced damage of the hippocampal CA1 neurons and upregulated NAIP expression in the rescued hippocampal CA1 neurons in a gerbil model. These data suggest that the NAIP upregulating compound, L-745,870, has therapeutic potential in acute ischemic disorders and that our NAIP-ELISA-based drug screening may facilitate the discovery of novel neuroprotective compounds.
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Affiliation(s)
- Yoshinori Okada
- Department of Molecular Neuroscience, The Institute of Medical Sciences, Tokai University, Isehara, Kanagawa, Japan
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45
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Yu Y, Matsuyama Y, Yanase M, Ito S, Adachi K, Satake K, Ishiguro N, Kiuchi K. Effects of hyperbaric oxygen on GDNF expression and apoptosis in spinal cord injury. Neuroreport 2005; 15:2369-73. [PMID: 15640758 DOI: 10.1097/00001756-200410250-00014] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The effects of hyperbaric oxygen treatment on the progress of secondary damage following traumatic spinal cord injury were investigated. The early onset of hyperbaric oxygen treatment significantly diminished the number of apoptotic cells 1 day after the injury. However, hyperbaric oxygen did not influence the proliferation of macrophages or activated microglia. The gene expression of glial cell line-derived neurotrophic factor (GDNF) and inducible nitric oxide synthetase (iNOS) was significantly attenuated 1 day after the injury in the hyperbaric oxygen groups compared with the control group. The down-regulation was confirmed by immunohistochemical staining. Early hyperbaric oxygen treatment was shown to effectively suppress the progress of apoptosis perhaps via the inhibition of iNOS gene despite the down-regulation of the GDNF gene.
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Affiliation(s)
- Yimin Yu
- Department of Orthopaedic Surgery, Nagoya University School of Medicine, 466-8500 Nagoya, Japan.
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46
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Abstract
Although it is apparent that neuronal death must be tightly regulated to ensure the proper development and mature functions of the nervous system, the molecular details of this regulation are not fully understood. In multiple neurodegenerative diseases, there is inappropriate death of cells in the nervous system. A better understanding of how death is regulated in the normal nervous system can provide a framework for determining how this regulation can go awry during neurodegenerative disease. The key executioners of neuronal apoptosis, the caspases, are regulated at several levels. The endogenous inhibitor of apoptosis family of proteins, the IAPs, can suppress caspase activity. In this Mini-Review, we examine what is known about the function of IAPs in normal neuronal function and in disease.
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Affiliation(s)
- Giselle F Prunell
- Departments of Pathology and Neurology, Taub Institute for the Study of Alzheimer's Disease and the Aging Brain, Columbia University College of Physicians and Surgeons, New York, New York 10032, USA
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47
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Wong LF, Ralph GS, Walmsley LE, Bienemann AS, Parham S, Kingsman SM, Uney JB, Mazarakis ND. Lentiviral-Mediated Delivery of Bcl-2 or GDNF Protects against Excitotoxicity in the Rat Hippocampus. Mol Ther 2005; 11:89-95. [PMID: 15585409 DOI: 10.1016/j.ymthe.2004.08.026] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2004] [Accepted: 08/31/2004] [Indexed: 11/25/2022] Open
Abstract
Nutrient deprivation during ischemia leads to severe insult to neurons causing widespread excitotoxic damage in specific brain regions such as the hippocampus. One possible strategy for preventing neurodegeneration is to express therapeutic proteins in the brain to protect against excitotoxicity. We investigated the utility of equine infectious anemia virus (EIAV)-based vectors as genetic tools for delivery of therapeutic proteins in an in vivo excitotoxicity model. The efficacy of these vectors at preventing cellular loss in target brain areas following excitotoxic insult was also assessed. EIAV vectors generated to overexpress the human antiapoptotic Bcl-2 or growth factor glial-derived neurotrophic factor (GDNF) genes protected against glutamate-induced toxicity in cultured hippocampal neurons. In an in vivo excitotoxicity model, adult Wistar rats received a unilateral dose of the glutamate receptor agonist N-methyl-D-aspartate to the hippocampus that induced a large lesion in the CA1 region. Neuronal loss could not be protected by prior transduction of a control vector expressing beta-galactosidase. In contrast, EIAV-mediated expression of Bcl-2 and GDNF significantly reduced lesion size thus protecting the hippocampus from excitotoxic damage. These results demonstrate that EIAV vectors can be effectively used to deliver putative neuroprotective genes to target brain areas and prevent cellular loss in the event of a neurological insult. Therefore these lentiviral vectors provide potential therapeutic tools for use in cases of acute neurotrauma such as cerebral ischemia.
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Affiliation(s)
- Liang-Fong Wong
- Oxford BioMedica (UK) Ltd., Medawar Centre, Robert Robinson Avenue, The Oxford Science Park, Oxford OX4 4GA, UK.
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Kells AP, Fong DM, Dragunow M, During MJ, Young D, Connor B. AAV-mediated gene delivery of BDNF or GDNF is neuroprotective in a model of Huntington disease. Mol Ther 2004; 9:682-8. [PMID: 15120329 DOI: 10.1016/j.ymthe.2004.02.016] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2003] [Accepted: 02/23/2004] [Indexed: 11/23/2022] Open
Abstract
Huntington disease (HD) is a neurodegenerative disorder that results in the progressive loss of GABAergic medium spiny projection neurons in the striatum. Neurotrophic factors have demonstrated neuroprotective actions on striatal neurons, suggesting that increased neurotrophic factor expression may prevent or reduce neuronal loss in the HD brain. We investigated whether enhanced expression of brain-derived neurotrophic factor (BDNF) or glial cell line-derived neurotrophic factor (GDNF), achieved by adeno-associated viral (AAV) vector-mediated gene delivery, could protect striatal neurons in the quinolinic acid (QA) rodent model of HD. Adult Wistar rats received unilateral intrastriatal injections of AAV-BDNF, AAV-GDNF, AAV-GFP, or PBS. Three weeks later, the rats were lesioned with QA, a toxin that induces striatal neuron death by an excitotoxic process. Both AAV-BDNF and AAV-GDNF significantly reduced the loss of both NeuN- and calbindin-immunopositive striatal neurons 2 weeks after lesion compared to controls. AAV-BDNF also provided significant neurotrophic support to NOS-immunopositive striatal interneurons, while AAV-GDNF-treated rats demonstrated significant protection of parvalbumin-immunopositive striatal interneurons compared to controls. These results indicate that AAV-mediated gene transfer of BDNF or GDNF into the striatum provides neuronal protection in a rodent model of HD.
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Affiliation(s)
- Adrian P Kells
- Department of Pharmacology and Clinical Pharmacology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
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Lindholm D, Arumäe U. Cell differentiation: reciprocal regulation of Apaf-1 and the inhibitor of apoptosis proteins. ACTA ACUST UNITED AC 2004; 167:193-5. [PMID: 15504905 PMCID: PMC2172544 DOI: 10.1083/jcb.200409171] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
The molecular mechanisms by which differentiated cells combat cell death and injury have remained unclear. In the current issue, it has been shown in neurons that cell differentiation is accompanied by a decrease in Apaf-1 and the activity of the apoptosome with an increased ability of the inhibitor of apoptosis proteins (IAPs) to sustain survival (Wright et al., 2004). These results, together with earlier ones, deepen our understanding of how cell death and the apoptosome are regulated during differentiation and in tumor cells.
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Affiliation(s)
- Dan Lindholm
- Department of Neuroscience, Uppsala University, Biomedical Centre, S-751 23 Uppsala, Sweden.
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Wright KM, Linhoff MW, Potts PR, Deshmukh M. Decreased apoptosome activity with neuronal differentiation sets the threshold for strict IAP regulation of apoptosis. ACTA ACUST UNITED AC 2004; 167:303-13. [PMID: 15504912 PMCID: PMC2172554 DOI: 10.1083/jcb.200406073] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Despite the potential of the inhibitor of apoptosis proteins (IAPs) to block cytochrome c-dependent caspase activation, the critical function of IAPs in regulating mammalian apoptosis remains unclear. We report that the ability of endogenous IAPs to effectively regulate caspase activation depends on the differentiation state of the cell. Despite being expressed at equivalent levels, endogenous IAPs afforded no protection against cytochrome c-induced apoptosis in naive pheochromocytoma (PC12) cells, but were remarkably effective in doing so in neuronally differentiated cells. Neuronal differentiation was also accompanied with a marked reduction in Apaf-1, resulting in a significant decrease in apoptosome activity. Importantly, this decrease in Apaf-1 protein was directly linked to the increased ability of IAPs to stringently regulate apoptosis in neuronally differentiated PC12 and primary cells. These data illustrate specifically how the apoptotic pathway acquires increased regulation with cellular differentiation, and are the first to show that IAP function and apoptosome activity are coupled in cells.
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Affiliation(s)
- Kevin M Wright
- Curriculum in Neurobiology, University of North Carolina, Chapel Hill, NC 27599, USA
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