1
|
Schaefers C, Schmeißer W, John H, Worek F, Rein T, Rothmiller S, Schmidt A. Effects of the nerve agent VX on hiPSC-derived motor neurons. Arch Toxicol 2024; 98:1859-1875. [PMID: 38555327 PMCID: PMC11106096 DOI: 10.1007/s00204-024-03708-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Accepted: 02/14/2024] [Indexed: 04/02/2024]
Abstract
Poisoning with the organophosphorus nerve agent VX can be life-threatening due to limitations of the standard therapy with atropine and oximes. To date, the underlying pathomechanism of VX affecting the neuromuscular junction has not been fully elucidated structurally. Results of recent studies investigating the effects of VX were obtained from cells of animal origin or immortalized cell lines limiting their translation to humans. To overcome this limitation, motor neurons (MN) of this study were differentiated from in-house feeder- and integration-free-derived human-induced pluripotent stem cells (hiPSC) by application of standardized and antibiotic-free differentiation media with the aim to mimic human embryogenesis as closely as possible. For testing VX sensitivity, MN were initially exposed once to 400 µM, 600 µM, 800 µM, or 1000 µM VX and cultured for 5 days followed by analysis of changes in viability and neurite outgrowth as well as at the gene and protein level using µLC-ESI MS/HR MS, XTT, IncuCyte, qRT-PCR, and Western Blot. For the first time, VX was shown to trigger neuronal cell death and decline in neurite outgrowth in hiPSC-derived MN in a time- and concentration-dependent manner involving the activation of the intrinsic as well as the extrinsic pathway of apoptosis. Consistent with this, MN morphology and neurite network were altered time and concentration-dependently. Thus, MN represent a valuable tool for further investigation of the pathomechanism after VX exposure. These findings might set the course for the development of a promising human neuromuscular test model and patient-specific therapies in the future.
Collapse
Affiliation(s)
- Catherine Schaefers
- Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstr. 11, 80937, Munich, Germany.
| | - Wolfgang Schmeißer
- Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstr. 11, 80937, Munich, Germany
| | - Harald John
- Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstr. 11, 80937, Munich, Germany
| | - Franz Worek
- Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstr. 11, 80937, Munich, Germany
| | - Theo Rein
- Max Planck Institute of Psychiatry, Kraepelinstr. 2-10, 80804, Munich, Germany
| | - Simone Rothmiller
- Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstr. 11, 80937, Munich, Germany
| | - Annette Schmidt
- Institute of Sport Science, University of the Bundeswehr Munich, Werner-Heisenberg-Weg 39, 85577, Neubiberg, Germany
| |
Collapse
|
2
|
Dehghan S, Kheshtchin N, Hassannezhad S, Soleimani M. Cell death classification: A new insight based on molecular mechanisms. Exp Cell Res 2023; 433:113860. [PMID: 38013091 DOI: 10.1016/j.yexcr.2023.113860] [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: 09/13/2023] [Revised: 11/17/2023] [Accepted: 11/18/2023] [Indexed: 11/29/2023]
Abstract
Cells tend to disintegrate themselves or are forced to undergo such destructive processes in critical circumstances. This complex cellular function necessitates various mechanisms and molecular pathways in order to be executed. The very nature of cell death is essentially important and vital for maintaining homeostasis, thus any type of disturbing occurrence might lead to different sorts of diseases and dysfunctions. Cell death has various modalities and yet, every now and then, a new type of this elegant procedure gets to be discovered. The diversity of cell death compels the need for a universal organizing system in order to facilitate further studies, therapeutic strategies and the invention of new methods of research. Considering all that, we attempted to review most of the known cell death mechanisms and sort them all into one arranging system that operates under a simple but subtle decision-making (If \ Else) order as a sorting algorithm, in which it decides to place and sort an input data (a type of cell death) into its proper set, then a subset and finally a group of cell death. By proposing this algorithm, the authors hope it may solve the problems regarding newer and/or undiscovered types of cell death and facilitate research and therapeutic applications of cell death.
Collapse
Affiliation(s)
- Sepehr Dehghan
- Department of Medical Basic Sciences, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Nasim Kheshtchin
- Department of Immunology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | | | - Maryam Soleimani
- Department of Medical Basic Sciences, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran.
| |
Collapse
|
3
|
Morén C, Treder N, Martínez-Pinteño A, Rodríguez N, Arbelo N, Madero S, Gómez M, Mas S, Gassó P, Parellada E. Systematic Review of the Therapeutic Role of Apoptotic Inhibitors in Neurodegeneration and Their Potential Use in Schizophrenia. Antioxidants (Basel) 2022; 11:2275. [PMID: 36421461 PMCID: PMC9686909 DOI: 10.3390/antiox11112275] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 11/02/2022] [Accepted: 11/03/2022] [Indexed: 09/15/2023] Open
Abstract
Schizophrenia (SZ) is a deleterious brain disorder affecting cognition, emotion and reality perception. The most widely accepted neurochemical-hypothesis is the imbalance of neurotransmitter-systems. Depleted GABAergic-inhibitory function might produce a regionally-located dopaminergic and glutamatergic-storm in the brain. The dopaminergic-release may underlie the positive psychotic-symptoms while the glutamatergic-release could prompt the primary negative symptoms/cognitive deficits. This may occur due to excessive synaptic-pruning during the neurodevelopmental stages of adolescence/early adulthood. Thus, although SZ is not a neurodegenerative disease, it has been suggested that exaggerated dendritic-apoptosis could explain the limited neuroprogression around its onset. This apoptotic nature of SZ highlights the potential therapeutic action of anti-apoptotic drugs, especially at prodromal stages. If dysregulation of apoptotic mechanisms underlies the molecular basis of SZ, then anti-apoptotic molecules could be a prodromal therapeutic option to halt or prevent SZ. In fact, risk alleles related in apoptotic genes have been recently associated to SZ and shared molecular apoptotic changes are common in the main neurodegenerative disorders and SZ. PRISMA-guidelines were considered. Anti-apoptotic drugs are commonly applied in classic neurodegenerative disorders with promising results. Despite both the apoptotic-hallmarks of SZ and the widespread use of anti-apoptotic targets in neurodegeneration, there is a strikingly scarce number of studies investigating anti-apoptotic approaches in SZ. We analyzed the anti-apoptotic approaches conducted in neurodegeneration and the potential applications of such anti-apoptotic therapies as a promising novel therapeutic strategy, especially during early stages.
Collapse
Affiliation(s)
- Constanza Morén
- Barcelona Clínic Schizophrenia Unit (BCSU), Institute of Neuroscience, Psychiatry and Psychology Service, Hospital Clínic of Barcelona, University of Barcelona, 08036 Barcelona, Spain
- Clinical and Experimental Neuroscience Area, The August Pi i Sunyer Biomedical Research Institute (IDIBAPS), 08036 Barcelona, Spain
- U722 Group, Centro de Investigación Biomédica en Red de Enfermedades Raras, CIBERER, Carlos III Health Institute, 28029 Madrid, Spain
- Department of Basic Clinical Practice, Pharmacology Unit, University of Barcelona, 08036 Barcelona, Spain
| | - Nina Treder
- Faculty of Psychology and Neuroscience, Maastricht University, 6211 LK Maastricht, The Netherlands
| | - Albert Martínez-Pinteño
- Department of Basic Clinical Practice, Pharmacology Unit, University of Barcelona, 08036 Barcelona, Spain
| | - Natàlia Rodríguez
- Department of Basic Clinical Practice, Pharmacology Unit, University of Barcelona, 08036 Barcelona, Spain
| | - Néstor Arbelo
- Barcelona Clínic Schizophrenia Unit (BCSU), Institute of Neuroscience, Psychiatry and Psychology Service, Hospital Clínic of Barcelona, University of Barcelona, 08036 Barcelona, Spain
- G04 Group, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Carlos III Health Institute, 28029 Madrid, Spain
| | - Santiago Madero
- Barcelona Clínic Schizophrenia Unit (BCSU), Institute of Neuroscience, Psychiatry and Psychology Service, Hospital Clínic of Barcelona, University of Barcelona, 08036 Barcelona, Spain
- G04 Group, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Carlos III Health Institute, 28029 Madrid, Spain
| | - Marta Gómez
- Barcelona Clínic Schizophrenia Unit (BCSU), Institute of Neuroscience, Psychiatry and Psychology Service, Hospital Clínic of Barcelona, University of Barcelona, 08036 Barcelona, Spain
- G04 Group, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Carlos III Health Institute, 28029 Madrid, Spain
- Department of Psychiatry, Servizo Galego de Saúde (SERGAS), 36001 Pontevedra, Spain
| | - Sergi Mas
- Clinical and Experimental Neuroscience Area, The August Pi i Sunyer Biomedical Research Institute (IDIBAPS), 08036 Barcelona, Spain
- Department of Basic Clinical Practice, Pharmacology Unit, University of Barcelona, 08036 Barcelona, Spain
- G04 Group, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Carlos III Health Institute, 28029 Madrid, Spain
| | - Patricia Gassó
- Clinical and Experimental Neuroscience Area, The August Pi i Sunyer Biomedical Research Institute (IDIBAPS), 08036 Barcelona, Spain
- Department of Basic Clinical Practice, Pharmacology Unit, University of Barcelona, 08036 Barcelona, Spain
- G04 Group, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Carlos III Health Institute, 28029 Madrid, Spain
| | - Eduard Parellada
- Barcelona Clínic Schizophrenia Unit (BCSU), Institute of Neuroscience, Psychiatry and Psychology Service, Hospital Clínic of Barcelona, University of Barcelona, 08036 Barcelona, Spain
- Clinical and Experimental Neuroscience Area, The August Pi i Sunyer Biomedical Research Institute (IDIBAPS), 08036 Barcelona, Spain
- Department of Basic Clinical Practice, Pharmacology Unit, University of Barcelona, 08036 Barcelona, Spain
- G04 Group, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Carlos III Health Institute, 28029 Madrid, Spain
| |
Collapse
|
4
|
Pathak A, Clark S, Bronfman FC, Deppmann CD, Carter BD. Long-distance regressive signaling in neural development and disease. WILEY INTERDISCIPLINARY REVIEWS. DEVELOPMENTAL BIOLOGY 2021; 10:e382. [PMID: 32391977 PMCID: PMC7655682 DOI: 10.1002/wdev.382] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 03/23/2020] [Accepted: 04/06/2020] [Indexed: 02/06/2023]
Abstract
Nervous system development proceeds via well-orchestrated processes involving a balance between progressive and regressive events including stabilization or elimination of axons, synapses, and even entire neurons. These progressive and regressive events are driven by functionally antagonistic signaling pathways with the dominant pathway eventually determining whether a neural element is retained or removed. Many of these developmental sculpting events are triggered by final target innervation necessitating a long-distance mode of communication. While long-distance progressive signaling has been well characterized, particularly for neurotrophic factors, there remains relatively little known about how regressive events are triggered from a distance. Here we discuss the emergent phenomenon of long-distance regressive signaling pathways. In particular, we will cover (a) progressive and regressive cues known to be employed after target innervation, (b) the mechanisms of long-distance signaling from an endosomal platform, (c) recent evidence that long-distance regressive cues emanate from platforms like death receptors or repulsive axon guidance receptors, and (d) evidence that these pathways are exploited in pathological scenarios. This article is categorized under: Nervous System Development > Vertebrates: General Principles Signaling Pathways > Global Signaling Mechanisms Establishment of Spatial and Temporal Patterns > Cytoplasmic Localization.
Collapse
Affiliation(s)
- Amrita Pathak
- Department of Biochemistry and Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Shayla Clark
- Neuroscience Graduate Program, University of Virginia, Charlottesville, Virginia
| | - Francisca C. Bronfman
- Institute of Biomedical Sciences (ICB), Faculty of Medicine, Faculty of Life Science, Universidad Andres Bello, Santiago, Chile
| | - Christopher D. Deppmann
- Departments of Biology, Cell Biology, Biomedical Engineering, and Neuroscience, University of Virginia, Charlottesville, Virginia
| | - Bruce D. Carter
- Department of Biochemistry and Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, Tennessee
| |
Collapse
|
5
|
p53 is required for nuclear but not mitochondrial DNA damage-induced degeneration. Cell Death Dis 2021; 12:104. [PMID: 33473103 PMCID: PMC7817838 DOI: 10.1038/s41419-020-03373-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 12/16/2020] [Accepted: 12/22/2020] [Indexed: 12/18/2022]
Abstract
While the consequences of nuclear DNA damage have been well studied, the exact consequences of acute and selective mitochondrial DNA (mtDNA) damage are less understood. DNA damaging chemotherapeutic drugs are known to activate p53-dependent apoptosis in response to sustained nuclear DNA damage. While it is recognized that whole-cell exposure to these drugs also damages mtDNA, the specific contribution of mtDNA damage to cellular degeneration is less clear. To examine this, we induced selective mtDNA damage in neuronal axons using microfluidic chambers that allow for the spatial and fluidic isolation of neuronal cell bodies (containing nucleus and mitochondria) from the axons (containing mitochondria). Exposure of the DNA damaging drug cisplatin selectively to only the axons induced mtDNA damage in axonal mitochondria, without nuclear damage. We found that this resulted in the selective degeneration of only the targeted axons that were exposed to DNA damage, where ROS was induced but mitochondria were not permeabilized. mtDNA damage-induced axon degeneration was not mediated by any of the three known axon degeneration pathways: apoptosis, axon pruning, and Wallerian degeneration, as Bax-deficiency, or Casp3-deficiency, or Sarm1-deficiency failed to protect the degenerating axons. Strikingly, p53, which is essential for degeneration after nuclear DNA damage, was also not required for degeneration induced with mtDNA damage. This was most evident when the p53-deficient neurons were globally exposed to cisplatin. While the cell bodies of p53-deficient neurons were protected from degeneration in this context, the axons farthest from the cell bodies still underwent degeneration. These results highlight how whole cell exposure to DNA damage activates two pathways of degeneration; a faster, p53-dependent apoptotic degeneration that is triggered in the cell bodies with nuclear DNA damage, and a slower, p53-independent degeneration that is induced with mtDNA damage.
Collapse
|
6
|
Neuronal cell life, death, and axonal degeneration as regulated by the BCL-2 family proteins. Cell Death Differ 2020; 28:108-122. [PMID: 33162554 PMCID: PMC7852532 DOI: 10.1038/s41418-020-00654-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Revised: 10/13/2020] [Accepted: 10/15/2020] [Indexed: 12/17/2022] Open
Abstract
Axonal degeneration and neuronal cell death are fundamental processes in development and contribute to the pathology of neurological disease in adults. Both processes are regulated by BCL-2 family proteins which orchestrate the permeabilization of the mitochondrial outer membrane (MOM). MOM permeabilization (MOMP) results in the activation of pro-apoptotic molecules that commit neurons to either die or degenerate. With the success of small-molecule inhibitors targeting anti-apoptotic BCL-2 proteins for the treatment of lymphoma, we can now envision the use of inhibitors of apoptosis with exquisite selectivity for BCL-2 family protein regulation of neuronal apoptosis in the treatment of nervous system disease. Critical to this development is deciphering which subset of proteins is required for neuronal apoptosis and axon degeneration, and how these two different outcomes are separately regulated. Moreover, noncanonical BCL-2 family protein functions unrelated to the regulation of MOMP, including impacting necroptosis and other modes of cell death may reveal additional potential targets and/or confounders. This review highlights our current understanding of BCL-2 family mediated neuronal cell death and axon degeneration, while identifying future research questions to be resolved to enable regulating neuronal survival pharmacologically.
Collapse
|
7
|
Peroxiredoxin 5 Silencing Sensitizes Dopaminergic Neuronal Cells to Rotenone via DNA Damage-Triggered ATM/p53/PUMA Signaling-Mediated Apoptosis. Cells 2019; 9:cells9010022. [PMID: 31861721 PMCID: PMC7016837 DOI: 10.3390/cells9010022] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 12/16/2019] [Accepted: 12/17/2019] [Indexed: 12/11/2022] Open
Abstract
Peroxiredoxins (Prxs) are a family of thioredoxin peroxidases. Accumulating evidence suggests that changes in the expression of Prxs may be involved in neurodegenerative diseases pathology. However, the expression and function of Prxs in Parkinson’s disease (PD) remains unclear. Here, we showed that Prx5 was the most downregulated of the six Prx subtypes in dopaminergic (DA) neurons in rotenone-induced cellular and rat models of PD, suggesting possible roles in regulating their survival. Depletion of Prx5 sensitized SH-SY5Y DA neuronal cells to rotenone-induced apoptosis. The extent of mitochondrial membrane potential collapse, cytochrome c release, and caspase activation was increased by Prx5 loss. Furthermore, Prx5 knockdown enhanced the induction of PUMA by rotenone through a p53-dependent mechanism. Using RNA interference approaches, we demonstrated that the p53/PUMA signaling was essential for Prx5 silencing-exacerbated mitochondria-driven apoptosis. Additionally, downregulation of Prx5 augmented rotenone-induced DNA damage manifested as induction of phosphorylated histone H2AX (γ-H2AX) and activation of ataxia telangiectasia mutated (ATM) kinase. The pharmacological inactivation of ATM revealed that ATM was integral to p53 activation by DNA damage. These findings provided a novel link between Prx5 and DNA damage-triggered ATM/p53/PUMA signaling in a rotenone-induced PD model. Thus, Prx5 might play an important role in protection against rotenone-induced DA neurodegeneration.
Collapse
|
8
|
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.
Collapse
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
| |
Collapse
|
9
|
Ciardullo C, Aptullahoglu E, Woodhouse L, Lin WY, Wallis JP, Marr H, Marshall S, Bown N, Willmore E, Lunec J. Non-genotoxic MDM2 inhibition selectively induces a pro-apoptotic p53 gene signature in chronic lymphocytic leukemia cells. Haematologica 2019; 104:2429-2442. [PMID: 31004033 PMCID: PMC6959162 DOI: 10.3324/haematol.2018.206631] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 04/16/2019] [Indexed: 12/28/2022] Open
Abstract
Chronic lymphocytic leukemia (CLL) is a clinically heterogeneous hematologic malignancy. In approximately 90% of cases the TP53 gene is in its wildtype state at diagnosis of this malignancy. As mouse double-minute-2 homolog (MDM2) is a primary repressor of p53, targeting this protein is an attractive therapeutic approach for non-genotoxic reactivation of p53. Since the discovery of the first MDM2 inhibitor, Nutlin-3a, newer potent and bioavailable compounds have been developed. In this study we tested the second-generation MDM2 inhibitor, RG7388, in patient-derived CLL cells and normal cells, examining its effect on the induction of p53-transcriptional targets. RG7388 potently decreased viability in p53-functional CLL cells, whereas p53-non-functional samples were more resistant to the drug. RG7388 induced a pro-apoptotic gene expression signature with upregulation of p53-target genes involved in the intrinsic (PUMA, BAX) and extrinsic (TNFRSF10B, FAS) pathways of apoptosis, as well as MDM2. Only a slight induction of CDKN1A was observed and upregulation of pro-apoptotic genes dominated, indicating that CLL cells are primed for p53-dependent apoptosis. Consequently, RG7388 led to a concentration-dependent increase in caspase-3/7 activity and cleaved poly (ADP-ribose) polymerase. Importantly, we observed a preferential pro-apoptotic signature in CLL cells but not in normal blood and bone marrow cells, including CD34+ hematopoietic cells. These data support the further evaluation of MDM2 inhibitors as a novel additional treatment option for patients with p53-functional CLL.
Collapse
Affiliation(s)
- Carmela Ciardullo
- Northern Institute for Cancer Research, Newcastle University, Newcastle upon Tyne
| | - Erhan Aptullahoglu
- Northern Institute for Cancer Research, Newcastle University, Newcastle upon Tyne
| | - Laura Woodhouse
- Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne
| | - Wei-Yu Lin
- Northern Institute for Cancer Research, Newcastle University, Newcastle upon Tyne
| | - Jonathan P Wallis
- Department of Haematology, Freeman Hospital, The Newcastle upon Tyne NHS Foundation Trust, Newcastle upon Tyne
| | - Helen Marr
- Department of Haematology, Freeman Hospital, The Newcastle upon Tyne NHS Foundation Trust, Newcastle upon Tyne
| | - Scott Marshall
- Department of Haematology, City Hospitals Sunderland NHS Trust, Sunderland
| | - Nick Bown
- Northern Genetics Service, Institute of Genetic Medicine, Newcastle upon Tyne, UK
| | - Elaine Willmore
- Northern Institute for Cancer Research, Newcastle University, Newcastle upon Tyne
| | - John Lunec
- Northern Institute for Cancer Research, Newcastle University, Newcastle upon Tyne
| |
Collapse
|
10
|
Geden MJ, Romero SE, Deshmukh M. Apoptosis versus axon pruning: Molecular intersection of two distinct pathways for axon degeneration. Neurosci Res 2018; 139:3-8. [PMID: 30452947 DOI: 10.1016/j.neures.2018.11.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Revised: 11/02/2018] [Accepted: 11/07/2018] [Indexed: 12/16/2022]
Abstract
Neurons are capable of degenerating their axons for the physiological clearance and refinement of unnecessary connections via the programmed degenerative pathways of apoptosis and axon pruning. While both pathways mediate axon degeneration they are however distinct. Whereas in apoptosis the entire neuron, both axons and cell body, degenerates, in the context of axon pruning only the targeted axon segments are selectively degenerated. Interestingly, the molecular pathways mediating axon degeneration in these two contexts have significant mechanistic overlap but also retain distinct differences. In this review, we describe the peripheral neuronal cell culture models used to study the molecular pathways of apoptosis and pruning. We outline what is known about the molecular mechanisms of apoptosis and axon pruning and focus on highlighting the similarities and differences of these two pathways.
Collapse
Affiliation(s)
- Matthew J Geden
- Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill, NC, 27599, USA; Neuroscience Center, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Selena E Romero
- Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill, NC, 27599, USA; Neuroscience Center, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Mohanish Deshmukh
- Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill, NC, 27599, USA; Neuroscience Center, University of North Carolina, Chapel Hill, NC, 27599, USA.
| |
Collapse
|
11
|
Comparing effects of CDK inhibition and E2F1/2 ablation on neuronal cell death pathways in vitro and after traumatic brain injury. Cell Death Dis 2018; 9:1121. [PMID: 30401820 PMCID: PMC6219504 DOI: 10.1038/s41419-018-1156-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 10/08/2018] [Accepted: 10/12/2018] [Indexed: 12/15/2022]
Abstract
Traumatic brain injury (TBI) activates multiple neuronal cell death mechanisms, leading to post-traumatic neuronal loss and neurological deficits. TBI-induced cell cycle activation (CCA) in post-mitotic neurons causes regulated cell death involving cyclin-dependent kinase (CDK) activation and initiation of an E2F transcription factor-mediated pro-apoptotic program. Here we examine the mechanisms of CCA-dependent neuronal apoptosis in primary neurons in vitro and in mice exposed to controlled cortical impact (CCI). In contrast to our prior work demonstrating robust neuroprotective effects by CDK inhibitors after TBI, examination of neuronal apoptotic mechanisms in E2F1−/−/E2F2−/− or E2F2−/− transgenic mice following CCI suggests that E2F1 and/or E2F2 likely play only a modest role in neuronal cell loss after brain trauma. To elucidate more critical CCA molecular pathways involved in post-traumatic neuronal cell death, we investigated the neuroprotective effects and mechanisms of the potent CDK inhibitor CR8 in a DNA damage model of cell death in primary cortical neurons. CR8 treatment significantly reduced caspase activation and cleavage of caspase substrates, attenuating neuronal cell death. CR8 neuroprotective effects appeared to reflect inhibition of multiple pathways converging on the mitochondrion, including injury-induced elevation of pro-apoptotic Bcl-2 homology region 3 (BH3)-only proteins Puma and Noxa, thereby attenuating mitochondrial permeabilization and release of cytochrome c and AIF, with reduction of both caspase-dependent and -independent apoptosis. CR8 administration also limited injury-induced deficits in mitochondrial respiration. These neuroprotective effects may be explained by CR8-mediated inhibition of key upstream injury responses, including attenuation of c-Jun phosphorylation/activation as well as inhibition of p53 transactivation of BH3-only targets.
Collapse
|
12
|
Fricker M, Tolkovsky AM, Borutaite V, Coleman M, Brown GC. Neuronal Cell Death. Physiol Rev 2018; 98:813-880. [PMID: 29488822 PMCID: PMC5966715 DOI: 10.1152/physrev.00011.2017] [Citation(s) in RCA: 673] [Impact Index Per Article: 112.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 05/23/2017] [Accepted: 07/10/2017] [Indexed: 02/07/2023] Open
Abstract
Neuronal cell death occurs extensively during development and pathology, where it is especially important because of the limited capacity of adult neurons to proliferate or be replaced. The concept of cell death used to be simple as there were just two or three types, so we just had to work out which type was involved in our particular pathology and then block it. However, we now know that there are at least a dozen ways for neurons to die, that blocking a particular mechanism of cell death may not prevent the cell from dying, and that non-neuronal cells also contribute to neuronal death. We review here the mechanisms of neuronal death by intrinsic and extrinsic apoptosis, oncosis, necroptosis, parthanatos, ferroptosis, sarmoptosis, autophagic cell death, autosis, autolysis, paraptosis, pyroptosis, phagoptosis, and mitochondrial permeability transition. We next explore the mechanisms of neuronal death during development, and those induced by axotomy, aberrant cell-cycle reentry, glutamate (excitoxicity and oxytosis), loss of connected neurons, aggregated proteins and the unfolded protein response, oxidants, inflammation, and microglia. We then reassess which forms of cell death occur in stroke and Alzheimer's disease, two of the most important pathologies involving neuronal cell death. We also discuss why it has been so difficult to pinpoint the type of neuronal death involved, if and why the mechanism of neuronal death matters, the molecular overlap and interplay between death subroutines, and the therapeutic implications of these multiple overlapping forms of neuronal death.
Collapse
Affiliation(s)
- Michael Fricker
- Hunter Medical Research Institute, University of Newcastle, Callaghan, New South Wales , Australia ; Department of Clinical Neurosciences, University of Cambridge , Cambridge , United Kingdom ; Neuroscience Institute, Lithuanian University of Health Sciences , Kaunas , Lithuania ; and Department of Biochemistry, University of Cambridge , Cambridge , United Kingdom
| | - Aviva M Tolkovsky
- Hunter Medical Research Institute, University of Newcastle, Callaghan, New South Wales , Australia ; Department of Clinical Neurosciences, University of Cambridge , Cambridge , United Kingdom ; Neuroscience Institute, Lithuanian University of Health Sciences , Kaunas , Lithuania ; and Department of Biochemistry, University of Cambridge , Cambridge , United Kingdom
| | - Vilmante Borutaite
- Hunter Medical Research Institute, University of Newcastle, Callaghan, New South Wales , Australia ; Department of Clinical Neurosciences, University of Cambridge , Cambridge , United Kingdom ; Neuroscience Institute, Lithuanian University of Health Sciences , Kaunas , Lithuania ; and Department of Biochemistry, University of Cambridge , Cambridge , United Kingdom
| | - Michael Coleman
- Hunter Medical Research Institute, University of Newcastle, Callaghan, New South Wales , Australia ; Department of Clinical Neurosciences, University of Cambridge , Cambridge , United Kingdom ; Neuroscience Institute, Lithuanian University of Health Sciences , Kaunas , Lithuania ; and Department of Biochemistry, University of Cambridge , Cambridge , United Kingdom
| | - Guy C Brown
- Hunter Medical Research Institute, University of Newcastle, Callaghan, New South Wales , Australia ; Department of Clinical Neurosciences, University of Cambridge , Cambridge , United Kingdom ; Neuroscience Institute, Lithuanian University of Health Sciences , Kaunas , Lithuania ; and Department of Biochemistry, University of Cambridge , Cambridge , United Kingdom
| |
Collapse
|
13
|
Ichikawa N, Alves M, Pfeiffer S, Langa E, Hernández-Santana YE, Suzuki H, Prehn JH, Engel T, Henshall DC. Deletion of the BH3-only protein Noxa alters electrographic seizures but does not protect against hippocampal damage after status epilepticus in mice. Cell Death Dis 2017; 8:e2556. [PMID: 28079889 PMCID: PMC5457684 DOI: 10.1038/cddis.2016.301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 08/23/2016] [Accepted: 08/25/2016] [Indexed: 12/19/2022]
Abstract
Several members of the Bcl-2 gene family are dysregulated in human temporal lobe epilepsy and animal studies show that genetic deletion of some of these proteins influence electrographic seizure responses to chemoconvulsants and associated brain damage. The BH3-only proteins form a subgroup comprising direct activators of Bax–Bak that are potently proapoptotic and a number of weaker proapoptotic BH3-only proteins that act as sensitizers by neutralization of antiapoptotic Bcl-2 family members. Noxa was originally characterized as a weaker proapoptotic, ‘sensitizer' BH3-only protein, although recent evidence suggests it too may be potently proapoptotic. Expression of Noxa is under p53 control, a known seizure-activated pathway, although Noxa has been linked to energetic stress and autophagy. Here we characterized the response of Noxa to prolonged seizures and the phenotype of mice lacking Noxa. Status epilepticus induced by intra-amygdala kainic acid caused a rapid increase in expression of noxa in the damaged CA3 subfield of the hippocampus but not undamaged CA1 region. In vivo upregulation of noxa was reduced by pifithrin-α, suggesting transcription may be partly p53-dependent. Mice lacking noxa developed less severe electrographic seizures during status epilepticus in the model but, surprisingly, displayed equivalent hippocampal damage to wild-type animals. The present findings indicate Noxa does not serve as a proapoptotic BH3-only protein during seizure-induced neuronal death in vivo. This study extends the comprehensive phenotyping of seizure and damage responses in mice lacking specific Bcl-2 gene family members and provides further evidence that these proteins may serve roles beyond control of cell death in the brain.
Collapse
Affiliation(s)
- Naoki Ichikawa
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, 123 St. Stephen's Green, Dublin 2, Ireland.,Department of Neurosurgery, Mie University Graduate School of Medicine, Tsu, Mie, Japan
| | - Mariana Alves
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, 123 St. Stephen's Green, Dublin 2, Ireland
| | - Shona Pfeiffer
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, 123 St. Stephen's Green, Dublin 2, Ireland
| | - Elena Langa
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, 123 St. Stephen's Green, Dublin 2, Ireland
| | - Yasmina E Hernández-Santana
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, 123 St. Stephen's Green, Dublin 2, Ireland
| | - Hidenori Suzuki
- Department of Neurosurgery, Mie University Graduate School of Medicine, Tsu, Mie, Japan
| | - Jochen Hm Prehn
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, 123 St. Stephen's Green, Dublin 2, Ireland
| | - Tobias Engel
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, 123 St. Stephen's Green, Dublin 2, Ireland
| | - David C Henshall
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, 123 St. Stephen's Green, Dublin 2, Ireland
| |
Collapse
|
14
|
Neniskyte U, Fricker M, Brown GC. Amyloid β induces microglia to phagocytose neurons via activation of protein kinase Cs and NADPH oxidase. Int J Biochem Cell Biol 2016; 81:346-355. [DOI: 10.1016/j.biocel.2016.06.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 05/25/2016] [Accepted: 06/03/2016] [Indexed: 10/21/2022]
|
15
|
Annis RP, Swahari V, Nakamura A, Xie AX, Hammond SM, Deshmukh M. Mature neurons dynamically restrict apoptosis via redundant premitochondrial brakes. FEBS J 2016; 283:4569-4582. [PMID: 27797453 DOI: 10.1111/febs.13944] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 09/20/2016] [Accepted: 10/26/2016] [Indexed: 12/30/2022]
Abstract
Apoptotic cell death is critical for the early development of the nervous system, but once the nervous system is established, the apoptotic pathway becomes highly restricted in mature neurons. However, the mechanisms underlying this increased resistance to apoptosis in these mature neurons are not completely understood. We have previously found that members of the miR-29 family of microRNAs (miRNAs) are induced with neuronal maturation and that overexpression of miR-29 was sufficient to restrict apoptosis in neurons. To determine whether endogenous miR-29 alone was responsible for the inhibition of cytochrome c release in mature neurons, we examined the status of the apoptotic pathway in sympathetic neurons deficient for all three miR-29 family members. Unexpectedly, we found that the apoptotic pathway remained largely restricted in miR-29-deficient mature neurons. We therefore probed for additional mechanisms by which mature neurons resist apoptosis. We identify miR-24 as another miRNA that is upregulated in the maturing cerebellum and sympathetic neurons that can act redundantly with miR-29 by targeting a similar repertoire of prodeath BH3-only genes. Overall, our results reveal that mature neurons engage multiple redundant brakes to restrict the apoptotic pathway and ensure their long-term survival.
Collapse
Affiliation(s)
- Ryan P Annis
- Neuroscience Center, UNC Chapel Hill, NC, USA.,Curriculum in Neurobiology, UNC Chapel Hill, NC, USA
| | | | - Ayumi Nakamura
- Neuroscience Center, UNC Chapel Hill, NC, USA.,Curriculum in Neurobiology, UNC Chapel Hill, NC, USA
| | - Alison X Xie
- Department of Pharmacology, UNC Chapel Hill, NC, USA
| | - Scott M Hammond
- Department of Cell Biology and Physiology, UNC Chapel Hill, NC, USA
| | - Mohanish Deshmukh
- Neuroscience Center, UNC Chapel Hill, NC, USA.,Curriculum in Neurobiology, UNC Chapel Hill, NC, USA.,Department of Cell Biology and Physiology, UNC Chapel Hill, NC, USA
| |
Collapse
|
16
|
Axon degeneration: context defines distinct pathways. Curr Opin Neurobiol 2016; 39:108-15. [PMID: 27197022 DOI: 10.1016/j.conb.2016.05.002] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 05/02/2016] [Accepted: 05/03/2016] [Indexed: 12/29/2022]
Abstract
Axon degeneration is an essential part of development, plasticity, and injury response and has been primarily studied in mammalian models in three contexts: 1) Axotomy-induced Wallerian degeneration, 2) Apoptosis-induced axon degeneration (axon apoptosis), and 3) Axon pruning. These three contexts dictate engagement of distinct pathways for axon degeneration. Recent advances have identified the importance of SARM1, NMNATs, NAD+ depletion, and MAPK signaling in axotomy-induced Wallerian degeneration. Interestingly, apoptosis-induced axon degeneration and axon pruning have many shared mechanisms both in signaling (e.g. DLK, JNKs, GSK3α/β) and execution (e.g. Puma, Bax, caspase-9, caspase-3). However, the specific mechanisms by which caspases are activated during apoptosis versus pruning appear distinct, with apoptosis requiring Apaf-1 but not caspase-6 while pruning requires caspase-6 but not Apaf-1.
Collapse
|
17
|
Simon DJ, Pitts J, Hertz NT, Yang J, Yamagishi Y, Olsen O, Tešić Mark M, Molina H, Tessier-Lavigne M. Axon Degeneration Gated by Retrograde Activation of Somatic Pro-apoptotic Signaling. Cell 2016; 164:1031-45. [PMID: 26898330 DOI: 10.1016/j.cell.2016.01.032] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 11/22/2015] [Accepted: 01/20/2016] [Indexed: 11/16/2022]
Abstract
During development, sensory axons compete for limiting neurotrophic support, and local neurotrophin insufficiency triggers caspase-dependent axon degeneration. The signaling driving axon degeneration upon local deprivation is proposed to reside within axons. Our results instead support a model in which, despite the apoptotic machinery being present in axons, the cell body is an active participant in gating axonal caspase activation and axon degeneration. Loss of trophic support in axons initiates retrograde activation of a somatic pro-apoptotic pathway, which, in turn, is required for distal axon degeneration via an anterograde pro-degenerative factor. At a molecular level, the cell body is the convergence point of two signaling pathways whose integrated action drives upregulation of pro-apoptotic Puma, which, unexpectedly, is confined to the cell body. Puma then overcomes inhibition by pro-survival Bcl-xL and Bcl-w and initiates the anterograde pro-degenerative program, highlighting the role of the cell body as an arbiter of large-scale axon removal.
Collapse
Affiliation(s)
- David J Simon
- Laboratory of Brain Development and Repair, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Jason Pitts
- Laboratory of Brain Development and Repair, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Nicholas T Hertz
- Laboratory of Brain Development and Repair, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Jing Yang
- Laboratory of Brain Development and Repair, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Yuya Yamagishi
- Laboratory of Brain Development and Repair, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Olav Olsen
- Laboratory of Brain Development and Repair, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Milica Tešić Mark
- Proteomics Resource Center, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Henrik Molina
- Proteomics Resource Center, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Marc Tessier-Lavigne
- Laboratory of Brain Development and Repair, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA.
| |
Collapse
|
18
|
Edwards AL, Gavathiotis E, LaBelle JL, Braun CR, Opoku-Nsiah KA, Bird GH, Walensky LD. Multimodal interaction with BCL-2 family proteins underlies the proapoptotic activity of PUMA BH3. ACTA ACUST UNITED AC 2014; 20:888-902. [PMID: 23890007 DOI: 10.1016/j.chembiol.2013.06.007] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Revised: 05/21/2013] [Accepted: 06/09/2013] [Indexed: 12/15/2022]
Abstract
PUMA is a proapoptotic BCL-2 family member that drives the apoptotic response to a diversity of cellular insults. Deciphering the spectrum of PUMA interactions that confer its context-dependent proapoptotic properties remains a high priority goal. Here, we report the synthesis of PUMA SAHBs, structurally stabilized PUMA BH3 helices that, in addition to broadly targeting antiapoptotic proteins, directly bind to proapoptotic BAX. NMR, photocrosslinking, and biochemical analyses revealed that PUMA SAHBs engage an α1/α6 trigger site on BAX to initiate its functional activation. We further demonstrated that a cell-permeable PUMA SAHB analog induces apoptosis in neuroblastoma cells and, like expressed PUMA protein, engages BCL-2, MCL-1, and BAX. Thus, we find that PUMA BH3 is a dual antiapoptotic inhibitor and proapoptotic direct activator, and its mimetics may serve as effective pharmacologic triggers of apoptosis in resistant human cancers.
Collapse
Affiliation(s)
- Amanda L Edwards
- Department of Pediatric Oncology, Linde Program in Cancer Chemical Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA
| | | | | | | | | | | | | |
Collapse
|
19
|
Kristiansen M, Ham J. Programmed cell death during neuronal development: the sympathetic neuron model. Cell Death Differ 2014; 21:1025-35. [PMID: 24769728 PMCID: PMC4207485 DOI: 10.1038/cdd.2014.47] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Revised: 03/05/2014] [Accepted: 03/13/2014] [Indexed: 01/08/2023] Open
Abstract
Developing sympathetic neurons of the superior cervical ganglion are one of the best studied models of neuronal apoptosis. These cells require nerve growth factor (NGF) for survival at the time that they innervate their final target tissues during late embryonic and early postnatal development. In the absence of NGF, developing sympathetic neurons die by apoptosis in a transcription-dependent manner. Molecular studies of sympathetic neuron apoptosis began in the 1980s. We now know that NGF withdrawal activates the mitochondrial (intrinsic) pathway of apoptosis in sympathetic neurons cultured in vitro, and the roles of caspases, Bcl-2 (B-cell CLL/lymphoma 2) family proteins and XIAP (X-linked inhibitor of apoptosis protein) have been extensively studied. Importantly, a considerable amount has also been learned about the intracellular signalling pathways and transcription factors that regulate programmed cell death in sympathetic neurons. In this article, we review the key papers published in the past few years, covering all aspects of apoptosis regulation in sympathetic neurons and focusing, in particular, on how signalling pathways and transcription factors regulate the cell death programme. We make some comparisons with other models of neuronal apoptosis and describe possible future directions for the field.
Collapse
Affiliation(s)
- M Kristiansen
- Molecular Haematology and Cancer Biology Unit, Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UK
| | - J Ham
- Molecular Haematology and Cancer Biology Unit, Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UK
| |
Collapse
|
20
|
|
21
|
Hagemeier K, Lürbke A, Hucke S, Albrecht S, Preisner A, Klassen E, Hoffmann E, Cui QL, Antel J J, Brück W, Klotz L, Kuhlmann T. Puma, but not noxa is essential for oligodendroglial cell death. Glia 2013; 61:1712-23. [DOI: 10.1002/glia.22552] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Revised: 06/06/2013] [Accepted: 06/11/2013] [Indexed: 12/30/2022]
Affiliation(s)
- Karin Hagemeier
- Institute of Neuropathology; University Hospital Münster; Pottkamp 2; 48149; Münster; Germany
| | - Alexander Lürbke
- Institute of Neuropathology; University Hospital Münster; Pottkamp 2; 48149; Münster; Germany
| | - Stephanie Hucke
- Department of Neurology-Inflammatory Disorders of the Nervous System and Neurooncology; University Hospital Münster; Domagkstr. 13; Münster; Germany
| | - Stefanie Albrecht
- Institute of Neuropathology; University Hospital Münster; Pottkamp 2; 48149; Münster; Germany
| | - Anna Preisner
- Institute of Neuropathology; University Hospital Münster; Pottkamp 2; 48149; Münster; Germany
| | - Elena Klassen
- Institute of Neuropathology; University Hospital Münster; Pottkamp 2; 48149; Münster; Germany
| | - Elke Hoffmann
- Institute of Neuropathology; University Hospital Münster; Pottkamp 2; 48149; Münster; Germany
| | - Qiao-Ling Cui
- Montreal Neurological Institute; McGill University; Montreal; Québec; Canada
| | - Jack Antel J
- Montreal Neurological Institute; McGill University; Montreal; Québec; Canada
| | - Wolfgang Brück
- Department of Neuropathology; University Medical Center Göttingen; Robert-Koch-Str. 40; 37075; Göttingen; Germany
| | - Luisa Klotz
- Department of Neurology-Inflammatory Disorders of the Nervous System and Neurooncology; University Hospital Münster; Domagkstr. 13; Münster; Germany
| | - Tanja Kuhlmann
- Institute of Neuropathology; University Hospital Münster; Pottkamp 2; 48149; Münster; Germany
| |
Collapse
|
22
|
Cui DR, Wang L, Jiang W, Qi AH, Zhou QH, Zhang XL. Propofol prevents cerebral ischemia-triggered autophagy activation and cell death in the rat hippocampus through the NF-κB/p53 signaling pathway. Neuroscience 2013; 246:117-32. [PMID: 23644056 DOI: 10.1016/j.neuroscience.2013.04.054] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2013] [Revised: 04/25/2013] [Accepted: 04/26/2013] [Indexed: 12/19/2022]
Abstract
Propofol (2,6-diisopropylphenol) has been shown to attenuate neuronal injury under a number of experimental conditions; however, the mechanisms involved in its neuroprotective effects remain unclear. We therefore investigated whether inhibition of p53 induction by propofol contributes to the neuroprotection of cerebral ischemic cell death through both autophagic and apoptotic mechanisms. A transient global cerebral ischemia-reperfusion (I/R) model was produced with a 10-min, 2-vessel occlusion. The change in target genes including damage-regulated autophagy modulator (DRAM), microtubule-associated protein 1 light chain 3 (LC3), Beclin 1, cathepsin D, cathepsin B, p53-upregulated modulator of apoptosis (PUMA), Bax and Bcl-2 upon p53 inhibition was assessed with the co-administration of the intravenous anesthetic propofol and 3-methyladenine (3-MA), Pifithrin-alpha (PFT-α) or SN50. The I/R-induced increases of protein levels of p53 and LC3-II were significantly inhibited by treatment with propofol, 3-MA or PFT-α. The I/R-induced increases of protein levels of DRAM, Beclin 1, active cathepsin D and cathepsin B were significantly inhibited by treatment with propofol, PFT-α or SN50. The negative effects of the I/R-induced up-regulation of PUMA and Bax and the down-regulation of Bcl-2 in the rat hippocampus were all blocked by treatment with propofol, PFT-α or SN50. Our results suggest that cerebral I/R can induce nuclear factor-kappa B-dependent expression of p53. The autophagic and apoptotic mechanisms participate in programed cell death by regulating the p53-mediated pathway. Our results are the first to show that propofol, at clinically relevant concentrations, attenuated cell death through both autophagic and apoptotic mechanisms in the rat hippocampus after a cerebral I/R insult.
Collapse
Affiliation(s)
- D R Cui
- Department of Anesthesiology, Shanghai Sixth People's Hospital Affiliated with Shanghai Jiaotong University, China
| | | | | | | | | | | |
Collapse
|
23
|
Ambacher KK, Pitzul KB, Karajgikar M, Hamilton A, Ferguson SS, Cregan SP. The JNK- and AKT/GSK3β- signaling pathways converge to regulate Puma induction and neuronal apoptosis induced by trophic factor deprivation. PLoS One 2012; 7:e46885. [PMID: 23056511 PMCID: PMC3463558 DOI: 10.1371/journal.pone.0046885] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Accepted: 09/07/2012] [Indexed: 12/17/2022] Open
Abstract
The AKT, GSK3 and JNK family kinases have been implicated in neuronal apoptosis associated with neuronal development and several neurodegenerative conditions. However, the mechanisms by which these kinase pathways regulate apoptosis remain unclear. In this study we have investigated the role of these kinases in neuronal cell death using an established model of trophic factor deprivation induced apoptosis in cerebellar granule neurons. BCL-2 family proteins are known to be central regulators of apoptosis and we have determined that the pro-apoptotic family member Puma is transcriptionally up-regulated in trophic factor deprived neurons and that Puma induction is required for apoptosis in vitro and in vivo. Importantly, we demonstrate that Puma induction is dependent on both JNK activation and AKT inactivation. AKT is known to regulate a number of downstream pathways, however we have determined that PI3K-AKT inactivation induces Puma expression through a GSK3β-dependent mechanism. Finally we demonstrate that the JNK and AKT/GSK3β pathways converge to regulate FoxO3a-mediated transcriptional activation of Puma. In summary we have identified a novel and critical link between the AKT, GSK3β and JNK kinases and the regulation of Puma induction and suggest that this may be pivotal to the regulation of neuronal apoptosis in neurodegenerative conditions.
Collapse
Affiliation(s)
- Kristin K. Ambacher
- Robarts Research Institute and Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada
| | - Kristen B. Pitzul
- Robarts Research Institute and Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada
| | - Meera Karajgikar
- Robarts Research Institute and Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada
| | - Alison Hamilton
- Robarts Research Institute and Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada
| | - Stephen S. Ferguson
- Robarts Research Institute and Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada
| | - Sean P. Cregan
- Robarts Research Institute and Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada
- * E-mail:
| |
Collapse
|
24
|
Ghosh AP, Klocke BJ, Ballestas ME, Roth KA. CHOP potentially co-operates with FOXO3a in neuronal cells to regulate PUMA and BIM expression in response to ER stress. PLoS One 2012; 7:e39586. [PMID: 22761832 PMCID: PMC3386252 DOI: 10.1371/journal.pone.0039586] [Citation(s) in RCA: 162] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Accepted: 05/28/2012] [Indexed: 12/23/2022] Open
Abstract
Endoplasmic reticulum (ER) stress-induced apoptosis has been implicated in various neurodegenerative diseases including Parkinson Disease, Alzheimer Disease and Huntington Disease. PUMA (p53 upregulated modulator of apoptosis) and BIM (BCL2 interacting mediator of cell death), pro-apoptotic BH3 domain-only, BCL2 family members, have previously been shown to regulate ER stress-induced cell death, but the upstream signaling pathways that regulate this response in neuronal cells are incompletely defined. Consistent with previous studies, we show that both PUMA and BIM are induced in response to ER stress in neuronal cells and that transcriptional induction of PUMA regulates ER stress-induced cell death, independent of p53. CHOP (C/EBP homologous protein also known as GADD153; gene name Ddit3), a critical initiator of ER stress-induced apoptosis, was found to regulate both PUMA and BIM expression in response to ER stress. We further show that CHOP knockdown prevents perturbations in the AKT (protein kinase B)/FOXO3a (forkhead box, class O, 3a) pathway in response to ER stress. CHOP co-immunoprecipitated with FOXO3a in tunicamycin treated cells, suggesting that CHOP may also regulate other pro-apoptotic signaling cascades culminating in PUMA and BIM activation and cell death. In summary, CHOP regulates the expression of multiple pro-apoptotic BH3-only molecules through multiple mechanisms, making CHOP an important therapeutic target relevant to a number of neurodegenerative conditions.
Collapse
Affiliation(s)
- Arindam P Ghosh
- Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | | | | | | |
Collapse
|
25
|
Ichim G, Tauszig-Delamasure S, Mehlen P. Neurotrophins and cell death. Exp Cell Res 2012; 318:1221-8. [PMID: 22465479 DOI: 10.1016/j.yexcr.2012.03.006] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Revised: 03/07/2012] [Accepted: 03/10/2012] [Indexed: 11/18/2022]
Abstract
The neurotrophins - NGF, BDNF, NT-3 - are secreted proteins that play a major role in neuron survival, differentiation and axon wiring toward target territories. They do so by interacting with their main tyrosine kinase receptors TrkA, TrkB, TrkC and p75(NTR). Even though there is a general consensus on the view that neurotrophins are survival factors, there are two fundamentally different views on how they achieve this survival activity. One prevailing view is that all neurons and more generally all normal cells are naturally committed to die unless a survival factor blocks this death. This death results from the engagement of a "default" apoptotic cell program. The minority report supports, on the opposite, that neurotrophin withdrawal is associated with an active signal of cell death induced by unbound dependence receptors. We will discuss here how neurotrophins regulate cell death and survival and how this has implications not only during nervous system development but also during cancer progression.
Collapse
Affiliation(s)
- Gabriel Ichim
- Apoptosis, Cancer and Development Laboratory, Equipe labellisée La Ligue, Centre de Recherche en Cancérologie de Lyon, INSERM U1052-CNRS UMR5286, Université de Lyon, Centre Léon Bérard, Lyon, France
| | | | | |
Collapse
|
26
|
Lee HR, Park SY, Kim HY, Shin HK, Lee WS, Rhim BY, Hong KW, Kim CD. Protection by cilostazol against amyloid-β1-40-induced suppression of viability and neurite elongation through activation of CK2α in HT22 mouse hippocampal cells. J Neurosci Res 2012; 90:1566-76. [DOI: 10.1002/jnr.23037] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Revised: 01/06/2012] [Accepted: 01/11/2012] [Indexed: 11/06/2022]
|
27
|
Fluazinam-induced apoptosis of SH-SY5Y cells is mediated by p53 and Bcl-2 family proteins. Neurotoxicology 2011; 32:702-10. [DOI: 10.1016/j.neuro.2011.08.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2011] [Revised: 07/26/2011] [Accepted: 08/21/2011] [Indexed: 12/25/2022]
|
28
|
Kristiansen M, Menghi F, Hughes R, Hubank M, Ham J. Global analysis of gene expression in NGF-deprived sympathetic neurons identifies molecular pathways associated with cell death. BMC Genomics 2011; 12:551. [PMID: 22067274 PMCID: PMC3256215 DOI: 10.1186/1471-2164-12-551] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Accepted: 11/08/2011] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Developing sympathetic neurons depend on nerve growth factor (NGF) for survival and die by apoptosis after NGF withdrawal. This process requires de novo gene expression but only a small number of genes induced by NGF deprivation have been identified so far, either by a candidate gene approach or in mRNA differential display experiments. This is partly because it is difficult to obtain large numbers of sympathetic neurons for in vitro studies. Here, we describe for the first time, how advances in gene microarray technology have allowed us to investigate the expression of all known genes in sympathetic neurons cultured in the presence and absence of NGF. RESULTS We have used Affymetrix Exon arrays to study the pattern of expression of all known genes in NGF-deprived sympathetic neurons. We identified 415 up- and 813 down-regulated genes, including most of the genes previously known to be regulated in this system. NGF withdrawal activates the mixed lineage kinase (MLK)-c-Jun N-terminal kinase (JNK)-c-Jun pathway which is required for NGF deprivation-induced death. By including a mixed lineage kinase (MLK) inhibitor, CEP-11004, in our experimental design we identified which of the genes induced after NGF withdrawal are potential targets of the MLK-JNK-c-Jun pathway. A detailed Gene Ontology and functional enrichment analysis also identified genetic pathways that are highly enriched and overrepresented amongst the genes expressed after NGF withdrawal. Five genes not previously studied in sympathetic neurons - trib3, ddit3, txnip, ndrg1 and mxi1 - were validated by real time-PCR. The proteins encoded by these genes also increased in level after NGF withdrawal and this increase was prevented by CEP-11004, suggesting that these genes are potential targets of the MLK-JNK-c-Jun pathway. CONCLUSIONS The sympathetic neuron model is one of the best studied models of neuronal apoptosis. Overall, our microarray data gives a comprehensive overview of, and provides new information about, signalling pathways and transcription factors that are regulated by NGF withdrawal.
Collapse
Affiliation(s)
- Mark Kristiansen
- Molecular Haematology and Cancer Biology Unit, Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UK
| | | | | | | | | |
Collapse
|
29
|
Hands S, Sajjad MU, Newton MJ, Wyttenbach A. In vitro and in vivo aggregation of a fragment of huntingtin protein directly causes free radical production. J Biol Chem 2011; 286:44512-20. [PMID: 21984825 DOI: 10.1074/jbc.m111.307587] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Neurodegenerative diseases are characterized by intra- and/or extracellular protein aggregation and oxidative stress. Intense attention has been paid to whether protein aggregation itself contributes to abnormal production of free radicals and ensuing cellular oxidative damage. Although this question has been investigated in the context of extracellular protein aggregation, it remains unclear whether protein aggregation inside cells alters the redox homeostasis. To address this, we have used in vitro and in vivo (cellular) models of Huntington disease, one of nine polyglutamine (poly(Q)) disorders, and examined the causal relationship among intracellular protein aggregation, reactive oxygen species (ROS) production, and toxicity. Live imaging of cells expressing a fragment of huntingtin (httExon1) with a poly(Q) expansion shows increased ROS production preceding cell death. ROS production is poly(Q) length-dependent and not due to the httExon 1 flanking sequence. Aggregation inhibition by the MW7 intrabody and Pgl-135 treatment abolishes ROS production, showing that increased ROS is caused by poly(Q) aggregation itself. To examine this hypothesis further, we determined whether aggregation of poly(Q) peptides in vitro generated free radicals. Monitoring poly(Q) protein aggregation using atomic force microscopy and hydrogen peroxide (H(2)O(2)) production over time in parallel we show that oligomerization of httEx1Q53 results in early generation of H(2)O(2). Inhibition of poly(Q) oligomerization by the single chain antibody MW7 abrogates H(2)O(2) formation. These results demonstrate that intracellular protein aggregation directly causes free radical production, and targeting potentially toxic poly(Q) oligomers may constitute a therapeutic target to counteract oxidative stress in poly(Q) diseases.
Collapse
Affiliation(s)
- Sarah Hands
- Southampton Neuroscience Group, School of Biological Sciences, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | | | | | | |
Collapse
|
30
|
Chatoo W, Abdouh M, Bernier G. p53 pro-oxidant activity in the central nervous system: implication in aging and neurodegenerative diseases. Antioxid Redox Signal 2011; 15:1729-37. [PMID: 20849375 DOI: 10.1089/ars.2010.3610] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Recent advances in delineating the biological functions of p53 had shed the light on its key role in the multifacets of cellular homeostasis. After its activation, via DNA damage, oxidative stress, or aberrant expression of oncogenes, p53 transduces its classical effect through several mechanisms comprising activation of the DNA repair machinery, cell cycle arrest, and initiation of apoptosis or senescence. In the mammalian brain, p53 plays critical functions in normal development, tumor suppression, neurodegenerative diseases, and aging. Herein, we focus on the constitutive pro-oxidant activity of p53 in neurons and discuss the potential implication of this finding in the context of neurodegenerative diseases and normal brain aging.
Collapse
Affiliation(s)
- Wassim Chatoo
- Developmental Biology Laboratory, Maisonneuve-Rosemont Hospital, 5415 Boulevard l'Assomption, Montréal, Canada
| | | | | |
Collapse
|
31
|
Palomo GM, Cerrato T, Gargini R, Diaz-Nido J. Silencing of frataxin gene expression triggers p53-dependent apoptosis in human neuron-like cells. Hum Mol Genet 2011; 20:2807-22. [PMID: 21531789 DOI: 10.1093/hmg/ddr187] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023] Open
Abstract
Friedreich's ataxia (FRDA) is an autosomal recessive disease caused by mutations that produce a deficiency in frataxin. Despite the importance of neurodegeneration in FRDA, little is known about the consequences of frataxin deficiency in neuronal cells. Here we describe a neuronal cell model for FRDA based on the use of lentiviral vectors that carry minigenes encoding frataxin-specific shRNAs that silence the expression of this gene. These lentivectors can knockdown frataxin expression in human neuroblastoma SH-SY5Y cells, which results in large-scale cell death in differentiated neuron-like cells but not in undifferentiated neuroblastoma cells. Frataxin-deficient neuron-like cells appear to die through apoptosis that is accompanied by up-regulation of p53, PUMA and Bax and activation of caspase-3. No significant autophagy is observed in frataxin-deficient neuron-like cells and the pharmacological activation of autophagy does not significantly increase neuronal cell death in response to the frataxin deficiency. Cell death triggered by frataxin knockdown can be impaired by interference with p53, caspase inhibitors and gene transfer of FXN. These results suggest that frataxin gene silencing in human neuron-like cells may constitute a useful cell model to characterize the molecular changes triggered by frataxin deficiency in neurons, as well as to search for therapies that may protect against neurodegeneration.
Collapse
Affiliation(s)
- Gloria M Palomo
- Departamento de Biología Molecular and Centro de Biología Molecular Severo Ochoa (UAM-CSIC), C/NicolásCabrera 1, Campus de Cantoblanco, Universidad Autónoma de Madrid, Madrid, Spain
| | | | | | | |
Collapse
|
32
|
Neuroprotective cytokines repress PUMA induction in the 1-methyl-4-phenylpyridinium (MPP(+)) model of Parkinson's disease. Biochem Biophys Res Commun 2011; 411:370-4. [PMID: 21741364 DOI: 10.1016/j.bbrc.2011.06.151] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Accepted: 06/24/2011] [Indexed: 01/01/2023]
Abstract
The hematopoietic cytokines erythropoietin (Epo) and granulocyte-colony stimulating factor (G-CSF) provide neuroprotection in several in vitro and in vivo models of Parkinson's disease (PD). The molecular mechanism by which Epo and G-CSF signals reduce the neuronal death in PD is not clear. Here, we show that in rat pheochromocytoma PC12 cells, Epo and G-CSF efficiently repressed the 1-methyl-4-phenylpyridinium (MPP(+))-induced expression of the proapoptotic protein PUMA (p53 up-regulated modulator of apoptosis). Accordingly, Epo and G-CSF treatment reduced the PC12 cell fraction that underwent apoptosis by MPP(+) treatment and thus improved cell viability. Downregulation of PUMA expression by Epo and G-CSF in MPP(+)-treated PC12 cells seems to be mediated by repression of p53, as the expression of p53 was increased by MPP(+)-treatment and reduced by Epo and G-CSF. Together, these results suggest that the neuroprotective activities of Epo and G-CSF in an experimental model of PD involve the repression of the apoptosis-inducing action of PUMA.
Collapse
|
33
|
In vivo contributions of BH3-only proteins to neuronal death following seizures, ischemia, and traumatic brain injury. J Cereb Blood Flow Metab 2011; 31:1196-210. [PMID: 21364604 PMCID: PMC3099642 DOI: 10.1038/jcbfm.2011.26] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The Bcl-2 homology (BH) domain 3-only proteins are a proapoptotic subgroup of the Bcl-2 gene family, which regulate cell death via effects on mitochondria. The BH3-only proteins react to various cell stressors and promote cell death by binding and inactivating antiapoptotic Bcl-2 family members and direct activation of proapoptotic multi-BH domain proteins such as Bax. Here, we review the in vivo evidence for their involvement in the pathophysiology of status epilepticus and contrast it to ischemia and traumatic brain injury. Seizures in rodents activate three potent proapoptotic BH3-only proteins: Bid, Bim, and Puma. Analysis of damage after seizures in mice singly deficient for each BH3-only protein supports a causal role for Puma and to a lesser extent Bim but, surprisingly, not Bid. In ischemia and trauma, where core aspects of the pathophysiology of cell death overlap, multiple BH3-only proteins are also activated and Bid has been shown to be required for neuronal death. The findings suggest that while each neurologic insult activates multiple BH3-only proteins, there may be specificity in their functional contribution. Future challenges include evaluating the remaining BH3-only proteins, explaining different causal contributions, and, if possible, exploring neurologic outcomes in mouse models deficient for multiple BH3-only proteins.
Collapse
|
34
|
Kaczmarek K, Studencka M, Meinhardt A, Wieczerzak K, Thoms S, Engel W, Grzmil P. Overexpression of peroxisomal testis-specific 1 protein induces germ cell apoptosis and leads to infertility in male mice. Mol Biol Cell 2011; 22:1766-79. [PMID: 21460186 PMCID: PMC3093327 DOI: 10.1091/mbc.e09-12-0993] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Peroxisomal testis-specific 1 gene (Pxt1) is the only male germ cell-specific gene that encodes a peroxisomal protein known to date. To elucidate the role of Pxt1 in spermatogenesis, we generated transgenic mice expressing a c-MYC-PXT1 fusion protein under the control of the PGK2 promoter. Overexpression of Pxt1 resulted in induction of male germ cells' apoptosis mainly in primary spermatocytes, finally leading to male infertility. This prompted us to analyze the proapoptotic character of mouse PXT1, which harbors a BH3-like domain in the N-terminal part. In different cell lines, the overexpression of PXT1 also resulted in a dramatic increase of apoptosis, whereas the deletion of the BH3-like domain significantly reduced cell death events, thereby confirming that the domain is functional and essential for the proapoptotic activity of PXT1. Moreover, we demonstrated that PXT1 interacts with apoptosis regulator BAT3, which, if overexpressed, can protect cells from the PXT1-induced apoptosis. The PXT1-BAT3 association leads to PXT1 relocation from the cytoplasm to the nucleus. In summary, we demonstrated that PXT1 induces apoptosis via the BH3-like domain and that this process is inhibited by BAT3.
Collapse
Affiliation(s)
- Karina Kaczmarek
- Institute of Human Genetics, Georg-August-University of Göttingen, 37073 Göttingen, Germany
| | | | | | | | | | | | | |
Collapse
|
35
|
Kole AJ, Swahari V, Hammond SM, Deshmukh M. miR-29b is activated during neuronal maturation and targets BH3-only genes to restrict apoptosis. Genes Dev 2011; 25:125-30. [PMID: 21245165 DOI: 10.1101/gad.1975411] [Citation(s) in RCA: 174] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The execution of apoptosis is critical for proper development of the nervous system. However, it is equally important that neurons strictly inhibit apoptosis after development to ensure their survival throughout the lifetime of the organism. Here we show that a microRNA, miR-29b, is markedly induced with neuronal maturation and functions as a novel inhibitor of neuronal apoptosis. The prosurvival function of miR-29b is mediated by targeting genes in the proapoptotic BH3-only family. Our results identify a unique strategy evolved by maturing neurons that uses a single microRNA to inhibit the multiple, redundant BH3-only proteins that are key initiators of apoptosis.
Collapse
Affiliation(s)
- Adam J Kole
- Department of Cell and Developmental Biology, University of North Carolina, Chapel Hill, North Carolina 27599, USA
| | | | | | | |
Collapse
|
36
|
The proapoptotic Bcl-2 protein Bax plays an important role in the pathogenesis of reovirus encephalitis. J Virol 2011; 85:3858-71. [PMID: 21307199 DOI: 10.1128/jvi.01958-10] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Encephalitis induced by reovirus serotype 3 (T3) strains results from the apoptotic death of infected neurons. Extrinsic apoptotic signaling is activated in reovirus-infected neurons in vitro and in vivo, but the role of intrinsic apoptosis signaling during encephalitis is largely unknown. Bax plays a key role in intrinsic apoptotic signaling in neurons by allowing the release of mitochondrial cytochrome c. We found Bax activation and cytochrome c release in neurons following infection of neonatal mice with T3 reoviruses. Bax(-/-) mice infected with T3 Abney (T3A) have reduced central nervous system (CNS) tissue injury and decreased apoptosis, despite viral replication that is similar to that in wild-type (WT) Bax(+/+) mice. In contrast, in the heart, T3A-infected Bax(-/-) mice have viral growth, caspase activation, and injury comparable to those in WT mice, indicating that the role of Bax in pathogenesis is organ specific. Nonmyocarditic T3 Dearing (T3D)-infected Bax(-/-) mice had delayed disease and enhanced survival compared to WT mice. T3D-infected Bax(-/-) mice had significantly lower viral titers and levels of activated caspase 3 in the brain despite unaffected transneuronal spread of virus. Cytochrome c and Smac release occurred in some reovirus-infected neurons in the absence of Bax; however, this was clearly reduced compared to levels seen in Bax(+/+) wild-type mice, indicating that Bax is necessary for efficient activation of proapoptotic mitochondrial signaling in infected neurons. Our studies suggest that Bax is important for reovirus growth and pathogenesis in neurons and that the intrinsic pathway of apoptosis, mediated by Bax, is important for full expression of disease, CNS tissue injury, apoptosis, and viral growth in the CNS of reovirus-infected mice.
Collapse
|
37
|
Neuronal apoptosis induced by endoplasmic reticulum stress is regulated by ATF4-CHOP-mediated induction of the Bcl-2 homology 3-only member PUMA. J Neurosci 2011; 30:16938-48. [PMID: 21159964 DOI: 10.1523/jneurosci.1598-10.2010] [Citation(s) in RCA: 260] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
An increasing body of evidence points to a key role of endoplasmic reticulum (ER) stress in acute and chronic neurodegenerative conditions. Extensive ER stress can trigger neuronal apoptosis, but the signaling pathways that regulate this cell death remain unclear. In the present study, we demonstrate that PUMA, a Bcl-2 homology 3 (BH3)-only member of the Bcl-2 family, is transcriptionally activated in cortical neurons by ER stress and is essential for ER-stress-induced cell death. PUMA is known to be a key transcriptional target of p53, but we have found that ER stress triggers PUMA induction and cell death through a p53-independent mechanism mediated by the ER-stress-inducible transcription factor ATF4 (activating transcription factor 4). Specifically, we demonstrate that ectopic expression of ATF4 sensitizes mouse cortical neurons to ER-stress-induced apoptosis and that ATF4-deficient neurons exhibit markedly reduced levels of PUMA expression and cell death. However, chromatin immunoprecipitation experiments suggest that ATF4 does not directly regulate the PUMA promoter. Rather, we found that ATF4 induces expression of the transcription factor CHOP (C/EBP homologous protein) and that CHOP in turn activates PUMA induction. Specifically, we demonstrate that CHOP binds to the PUMA promoter during ER stress and that CHOP knockdown attenuates PUMA induction and neuronal apoptosis. In summary, we have identified a key signaling pathway in ER-stress-induced neuronal death involving ATF4-CHOP-mediated transactivation of the proapoptotic Bcl-2 family member PUMA. We propose that this pathway may be an important therapeutic target relevant to a number of neurodegenerative conditions.
Collapse
|
38
|
Ola MS, Nawaz M, Ahsan H. Role of Bcl-2 family proteins and caspases in the regulation of apoptosis. Mol Cell Biochem 2011; 351:41-58. [PMID: 21210296 DOI: 10.1007/s11010-010-0709-x] [Citation(s) in RCA: 670] [Impact Index Per Article: 51.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2010] [Accepted: 12/13/2010] [Indexed: 12/12/2022]
Abstract
Apoptosis, or programmed cell death, plays a pivotal role in the elimination of unwanted, damaged, or infected cells in multicellular organisms and also in diverse biological processes, including development, cell differentiation, and proliferation. Apoptosis is a highly regulated form of cell death, and dysregulation of apoptosis results in pathological conditions including cancer, autoimmune and neurodegenerative diseases. The Bcl-2 family proteins are key regulators of apoptosis, which include both anti- and pro-apoptotic proteins, and a slight change in the dynamic balance of these proteins may result either in inhibition or promotion of cell death. Execution of apoptosis by various stimuli is initiated by activating either intrinsic or extrinsic pathways which lead to a series of downstream cascade of events, releasing of various apoptotic mediators from mitochondria and activation of caspases, important for the cell fate. In view of recent research advances about underlying mechanism of apoptosis, this review highlights the basics concept of apoptosis and its regulation by Bcl-2 family of protein. Furthermore, this review discusses the interplay of various apoptotic mediators and caspases to decide the fate of the cell. We expect that this review will add to the pool of basic information necessary to understand the mechanism of apoptosis which may implicate in designing better strategy to develop biomedical therapy to control apoptosis.
Collapse
Affiliation(s)
- Mohammad Shamsul Ola
- Department of Ophthalmology, College of Medicine, King Saud University, Riyadh 11411, KSA
| | | | | |
Collapse
|
39
|
Bernstein AI, Garrison SP, Zambetti GP, O'Malley KL. 6-OHDA generated ROS induces DNA damage and p53- and PUMA-dependent cell death. Mol Neurodegener 2011; 6:2. [PMID: 21211034 PMCID: PMC3025875 DOI: 10.1186/1750-1326-6-2] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Accepted: 01/06/2011] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Parkinson's disease (PD) is characterized by the selective loss of dopaminergic neurons in the substantia nigra (SN), resulting in tremor, rigidity, and bradykinesia. Although the etiology is unknown, insight into the disease process comes from the dopamine (DA) derivative, 6-hydroxydopamine (6-OHDA), which produces PD-like symptoms. Studies show that 6-OHDA activates stress pathways, such as the unfolded protein response (UPR), triggers mitochondrial release of cytochrome-c, and activates caspases, such as caspase-3. Because the BH3-only protein, Puma (p53-upregulated mediator of apoptosis), is activated in response to UPR, it is thought to be a link between cell stress and apoptosis. RESULTS To test the hypothesis that Puma serves such a role in 6-OHDA-mediated cell death, we compared the response of dopaminergic neurons from wild-type and Puma-null mice to 6-OHDA. Results indicate that Puma is required for 6-OHDA-induced cell death, in primary dissociated midbrain cultures as well as in vivo. In these cultures, 6-OHDA-induced DNA damage and p53 were required for 6-OHDA-induced cell death. In contrast, while 6-OHDA led to upregulation of UPR markers, loss of ATF3 did not protect against 6-OHDA. CONCLUSIONS Together, our results indicate that 6-OHDA-induced upregulation of Puma and cell death are independent of UPR. Instead, p53 and DNA damage repair pathways mediate 6-OHDA-induced toxicity.
Collapse
Affiliation(s)
- Alison I Bernstein
- Department of Anatomy and Neurobiology, Washington University School of Medicine, St, Louis, MO 63110, USA.
| | | | | | | |
Collapse
|
40
|
Hughes R, Kristiansen M, Lassot I, Desagher S, Mantovani R, Ham J. NF-Y is essential for expression of the proapoptotic bim gene in sympathetic neurons. Cell Death Differ 2010; 18:937-47. [PMID: 21164521 DOI: 10.1038/cdd.2010.166] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Neuronal apoptosis has a major role during development and aberrant apoptosis contributes to the pathology of certain neurological conditions. Studies with nerve growth factor (NGF)-dependent sympathetic neurons have provided important insights into the molecular mechanisms of neuronal apoptosis and the signalling pathways that regulate the cell death programme in neurons. The BH3-only protein Bim is a critical mediator of apoptosis in many cell types and in sympathetic neurons is required for NGF withdrawal-induced death. However, regulation of bim expression is complex and remains incompletely understood. We report that a conserved inverted CCAAT box (ICB) in the rat bim promoter is bound by the heterotrimeric transcription factor NF-Y. Interestingly, NF-Y is required for bim promoter activity and its induction following NGF withdrawal. We demonstrate that NF-Y activity is essential for endogenous Bim expression and contributes to NGF withdrawal-induced death. Furthermore, we find that the transcriptional coactivators CBP and p300 interact with NF-Y and FOXO3a and bind to this region of the bim promoter. The amount of CBP/p300 bound to bim increases after NGF deprivation and inhibition of CBP/p300 activity reduces bim induction. Our results indicate that NF-Y cooperates with FOXO3a to recruit CBP/p300 to the bim promoter to form a stable multi-protein/DNA complex that activates bim transcription after survival factor withdrawal.
Collapse
Affiliation(s)
- R Hughes
- Molecular Haematology and Cancer Biology Unit, Institute of Child Health, University College London, London, UK
| | | | | | | | | | | |
Collapse
|
41
|
Fricker M, Papadia S, Hardingham GE, Tolkovsky AM. Implication of TAp73 in the p53-independent pathway of Puma induction and Puma-dependent apoptosis in primary cortical neurons. J Neurochem 2010; 114:772-83. [PMID: 20477944 PMCID: PMC2956137 DOI: 10.1111/j.1471-4159.2010.06804.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Puma (p53 up-regulated modulator of apoptosis) is a BH3-only protein member of the Bcl-2 family that controls apoptosis by regulating the release of pro-apoptotic factors from mitochondria. Previously, we reported that sodium arsenite (NaAsO(2)) induces Puma-dependent apoptosis in cortical neurons in a p53-independent manner. The following evidence shows that p53-independent Puma activation by NaAsO(2) is mediated by the p53-related protein TAp73: (i) NaAsO(2) causes TAp73alpha accumulation and increases p53-independent expression of p73 target genes; (ii) two p53 response elements in the Puma promoter are required for NaAsO(2)-mediated activation of a Puma reporter construct; (iii) expression of the inhibitory DeltaNp73alpha and DeltaNp73beta isoforms decreases NaAsO(2)-mediated induction of Puma and other p53-family target genes in a p53-null background; (iv) DeltaNp73alpha and DeltaNp73beta expression protects the neurons from NaAsO(2)-dependent apoptosis. Interestingly, although ER stressors also induce p53-independent, Puma-dependent apoptosis, they do not increase TAp73 expression while NaAsO(2) does not induce notable endoplasmic reticulum (ER) stress. In contrast, DNA damaging agents, okadaic acid, and H(2)O(2) all induce apoptosis in a strictly Puma- and p53-dependent manner. Hence, the pivotal position of Puma as mediator of apoptosis in cortical neurons is because of the availability of at least three independent signalling pathways that ensure its activation.
Collapse
Affiliation(s)
- Michael Fricker
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| | - Sofia Papadia
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh EH8 9XD, UK
| | - Giles E. Hardingham
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh EH8 9XD, UK
| | - Aviva M. Tolkovsky
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| |
Collapse
|
42
|
Pizarro JG, Folch J, de la Torre AV, Junyent F, Verdaguer E, Jordan J, Pallas M, Camins A. ATM is involved in cell-cycle control through the regulation of retinoblastoma protein phosphorylation. J Cell Biochem 2010; 110:210-8. [PMID: 20213763 DOI: 10.1002/jcb.22528] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Ataxia telangiectasia mutated protein (ATM) is a member of the phosphatidylinositol-3 kinase (PI3K) family, which has a role in the cellular response to DNA double-strand breaks (DSBs). In the present study, we evaluated the role of ATM in cell-cycle control in dopaminergic rat neuroblastoma B65 cells. For this purpose, ATM activity was either inhibited pharmacologically with the specific inhibitor KU-55933, or the ATM gene was partially silenced by transfection with small interfering RNA (siRNA). Our data indicate that although ATM inhibition did not affect the cell cycle, both treatments specifically decreased the levels of cyclin A and retinoblastoma protein (pRb), phosphorylated at Ser780. Furthermore, ATM inhibition decreased the active form of p53, which is phosphorylated at Ser15, and also decreased Bax and p21 expression. Using H(2)O(2) as a positive control of DSBs, caused a rapid pRb phosphorylation, this was prevented by KU-55933 and siRNA treatment. Collectively, our data demonstrate how a new molecular network on ATM regulates the cell cycle through the control of pRb phosphorylation. These findings support a new target of ATM.
Collapse
Affiliation(s)
- Javier G Pizarro
- Unitat de Farmacologia i Farmacognosia, Institut de Biomedicina (IBUB), Centro deInvestigacion Biomedica en Red de Enfermedades Neurodegenerativas (CIBERNED), Facultat de Farmacia, Universitat de Barcelona, Nucli Universitari de Pedralbes, Barcelona E-08028, Spain
| | | | | | | | | | | | | | | |
Collapse
|
43
|
Lee SB, Kwon IS, Park J, Lee KH, Ahn Y, Lee C, Kim J, Choi SY, Cho SW, Ahn JY. Ribosomal protein S3, a new substrate of Akt, serves as a signal mediator between neuronal apoptosis and DNA repair. J Biol Chem 2010; 285:29457-68. [PMID: 20605787 DOI: 10.1074/jbc.m110.131367] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
RPS3, a conserved, eukaryotic ribosomal protein of the 40 S subunit, is required for ribosome biogenesis. Because ribosomal proteins are abundant and ubiquitous, they may have additional extraribosomal functions. Here, we show that human RPS3 is a physiological target of Akt kinase and a novel mediator of neuronal apoptosis. NGF stimulation resulted in phosphorylation of threonine 70 of RPS3 by Akt, and this phosphorylation was required for Akt binding to RPS3. RPS3 induced neuronal apoptosis, up-regulating proapoptotic proteins Dp5/Hrk and Bim by binding to E2F1 and acting synergistically with it. Akt-dependent phosphorylation of RPS3 inhibited its proapoptotic function and perturbed its interaction with E2F1. These events coincided with nuclear translocation and accumulation of RPS3, where it functions as an endonuclease. Nuclear accumulation of RPS3 results in an increase in DNA repair activity to some extent, thereby sustaining neuronal survival. Abolishment of Akt-mediated RPS3 phosphorylation through mutagenesis accelerated apoptotic cell death and severely compromised nuclear translocation of RPS3. Thus, our findings define an extraribosomal role of RPS3 as a molecular switch that accommodates apoptotic induction to DNA repair through Akt-mediated phosphorylation.
Collapse
Affiliation(s)
- Sang Bae Lee
- Department of Molecular Cell Biology, Biomedical Research Institute, Sungkyunkwan University School of Medicine, Suwon, Korea
| | | | | | | | | | | | | | | | | | | |
Collapse
|
44
|
Abstract
Developmental and pathological death of neurons requires activation of a defined pathway of cell cycle proteins. However, it is unclear how this pathway is regulated and whether it is relevant in vivo. A screen for transcripts robustly induced in cultured neurons by DNA damage identified Sertad1, a Cdk4 (cyclin-dependent kinase 4) activator. Sertad1 is also induced in neurons by nerve growth factor (NGF) deprivation and Abeta (beta-amyloid). RNA interference-mediated downregulation of Sertad1 protects neurons in all three death models. Studies of NGF withdrawal indicate that Sertad1 is required to initiate the apoptotic cell cycle pathway since its knockdown blocks subsequent pathway events. Finally, we find that Sertad1 expression is required for developmental neuronal death in the cerebral cortex. Sertad1 thus appears to be essential for neuron death in trophic support deprivation in vitro and in vivo and in models of DNA damage and Alzheimer's disease. It may therefore be a suitable target for therapeutic intervention.
Collapse
|
45
|
Abstract
Synaptic activity promotes resistance to diverse apoptotic insults, the mechanism behind which is incompletely understood. We show here that a coordinated downregulation of core components of the intrinsic apoptosis pathway by neuronal activity forms a key part of the underlying mechanism. Activity-dependent protection against apoptotic insults is associated with inhibition of cytochrome c release in most but not all neurons, indicative of anti-apoptotic signaling both upstream and downstream of this step. We find that enhanced firing activity suppresses expression of the proapoptotic BH3-only member gene Puma in a NMDA receptor-dependent, p53-independent manner. Puma expression is sufficient to induce cytochrome c loss and neuronal apoptosis. Puma deficiency protects neurons against apoptosis and also occludes the protective effect of synaptic activity, while blockade of physiological NMDA receptor activity in the developing mouse brain induces neuronal apoptosis that is preceded by upregulation of Puma. However, enhanced activity can also confer resistance to Puma-induced apoptosis, acting downstream of cytochrome c release. This mechanism is mediated by transcriptional suppression of apoptosome components Apaf-1 and procaspase-9, and limiting caspase-9 activity, since overexpression of procaspase-9 accelerates the rate of apoptosis in active neurons back to control levels. Synaptic activity does not exert further significant anti-apoptotic effects downstream of caspase-9 activation, since an inducible form of caspase-9 overrides the protective effect of synaptic activity, despite activity-induced transcriptional suppression of caspase-3. Thus, suppression of apoptotic gene expression may synergize with other activity-dependent events such as enhancement of antioxidant defenses to promote neuronal survival.
Collapse
|
46
|
Multifaceted deaths orchestrated by mitochondria in neurones. Biochim Biophys Acta Mol Basis Dis 2010; 1802:167-85. [DOI: 10.1016/j.bbadis.2009.09.004] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2009] [Revised: 09/07/2009] [Accepted: 09/08/2009] [Indexed: 12/16/2022]
|
47
|
Abstract
PUMA (p53 upregulated modulator of apoptosis) is a Bcl-2 homology 3 (BH3)-only Bcl-2 family member and a critical mediator of p53-dependent and -independent apoptosis induced by a wide variety of stimuli, including genotoxic stress, deregulated oncogene expression, toxins, altered redox status, growth factor/cytokine withdrawal and infection. It serves as a proximal signaling molecule whose expression is regulated by transcription factors in response to these stimuli. PUMA transduces death signals primarily to the mitochondria, where it acts indirectly on the Bcl-2 family members Bax and/or Bak by relieving the inhibition imposed by antiapoptotic members. It directly binds and antagonizes all known antiapoptotic Bcl-2 family members to induce mitochondrial dysfunction and caspase activation. PUMA ablation or inhibition leads to apoptosis deficiency underlying increased risks for cancer development and therapeutic resistance. Although elevated PUMA expression elicits profound chemo- and radiosensitization in cancer cells, inhibition of PUMA expression may be useful for curbing excessive cell death associated with tissue injury and degenerative diseases. Therefore, PUMA is a general sensor of cell death stimuli and a promising drug target for cancer therapy and tissue damage.
Collapse
Affiliation(s)
- J Yu
- Department of Pathology, University of Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | | |
Collapse
|
48
|
Pizarro JG, Folch J, Vazquez De la Torre A, Verdaguer E, Junyent F, Jordán J, Pallàs M, Camins A. Oxidative stress-induced DNA damage and cell cycle regulation in B65 dopaminergic cell line. Free Radic Res 2009; 43:985-94. [DOI: 10.1080/10715760903159188] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|
49
|
Niizuma K, Endo H, Chan PH. Oxidative stress and mitochondrial dysfunction as determinants of ischemic neuronal death and survival. J Neurochem 2009; 109 Suppl 1:133-8. [PMID: 19393019 DOI: 10.1111/j.1471-4159.2009.05897.x] [Citation(s) in RCA: 283] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Mitochondria are the powerhouse of the cell. Their primary physiological function is to generate adenosine triphosphate through oxidative phosphorylation via the electron transport chain. Reactive oxygen species generated from mitochondria have been implicated in acute brain injuries such as stroke and neurodegeneration. Recent studies have shown that mitochondrially-formed oxidants are mediators of molecular signaling, which is implicated in the mitochondria-dependent apoptotic pathway that involves pro- and antiapoptotic protein binding, the release of cytochrome c, and transcription-independent p53 signaling, leading to neuronal death. Oxidative stress and the redox state of ischemic neurons are also implicated in the signaling pathway that involves phosphatidylinositol 3-kinase/Akt and downstream signaling, which lead to neuronal survival. Genetically modified mice or rats that over-express or are deficient in superoxide dismutase have provided strong evidence in support of the role of mitochondrial dysfunction and oxidative stress as determinants of neuronal death/survival after stroke and neurodegeneration.
Collapse
Affiliation(s)
- Kuniyasu Niizuma
- Department of Neurosurgery, Stanford University School of Medicine, Stanford, California 94305-5487, USA
| | | | | |
Collapse
|
50
|
Abstract
Members of the Bcl-2 family are essential regulators of programmed cell death and thus play a major role in the development and function of many tissues. The balance between pro-survival and pro-apoptotic members of the family decides whether a cell will live or die. This mechanism allows organisms to get rid of cells that are no longer needed or have become dangerous. Deregulation of apoptosis is a major contributing factor in the development of many diseases. A deeper understanding of how the Bcl-2 family proteins orchestrate death in normal and pathologic conditions is thus relevant not only for disease etiology, but also to try to prevent these various disorders. Experiments with transgenic and gene-ablated mice have helped elucidate the function of the different members of the Bcl-2 family and their physiological roles. The present review highlights the role of Bcl-2 family members in autoimmune and degenerative disorders, with a particular focus on the mouse models that have been used to study their function.
Collapse
|