1
|
Morello G, La Cognata V, Guarnaccia M, D'Agata V, Cavallaro S. Cracking the Code of Neuronal Cell Fate. Cells 2023; 12:cells12071057. [PMID: 37048129 PMCID: PMC10093029 DOI: 10.3390/cells12071057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 03/27/2023] [Accepted: 03/29/2023] [Indexed: 04/03/2023] Open
Abstract
Transcriptional regulation is fundamental to most biological processes and reverse-engineering programs can be used to decipher the underlying programs. In this review, we describe how genomics is offering a systems biology-based perspective of the intricate and temporally coordinated transcriptional programs that control neuronal apoptosis and survival. In addition to providing a new standpoint in human pathology focused on the regulatory program, cracking the code of neuronal cell fate may offer innovative therapeutic approaches focused on downstream targets and regulatory networks. Similar to computers, where faults often arise from a software bug, neuronal fate may critically depend on its transcription program. Thus, cracking the code of neuronal life or death may help finding a patch for neurodegeneration and cancer.
Collapse
Affiliation(s)
- Giovanna Morello
- Institute for Biomedical Research and Innovation, National Research Council (CNR-IRIB), 95126 Catania, Italy
| | - Valentina La Cognata
- Institute for Biomedical Research and Innovation, National Research Council (CNR-IRIB), 95126 Catania, Italy
| | - Maria Guarnaccia
- Institute for Biomedical Research and Innovation, National Research Council (CNR-IRIB), 95126 Catania, Italy
| | - Velia D'Agata
- Section of Human Anatomy and Histology, Department of Biomedical and Biotechnological Sciences, University of Catania, 95124 Catania, Italy
| | - Sebastiano Cavallaro
- Institute for Biomedical Research and Innovation, National Research Council (CNR-IRIB), 95126 Catania, Italy
| |
Collapse
|
2
|
Canu N, Ciotti MT, Pollegioni L. Serine racemase: a key player in apoptosis and necrosis. Front Synaptic Neurosci 2014; 6:9. [PMID: 24795622 PMCID: PMC4000995 DOI: 10.3389/fnsyn.2014.00009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Accepted: 03/28/2014] [Indexed: 12/14/2022] Open
Abstract
A fine balance between cell survival and cell death is required to sculpt the nervous system during development. However, an excess of cell death can occur following trauma, exposure to neurotoxins or alcohol, and some developmental and neurodegenerative diseases, such as Alzheimer's disease (AD). N-Methyl-D-aspartate receptors (NMDARs) support synaptic plasticity and survival of many neuronal populations whereas inappropriate activation may promote various forms of cell death, apoptosis, and necrosis representing the two extremes of a continuum of cell death processes both “in vitro” and “in vivo.” Hence, by identifying the switches controlling pro-survival vs. apoptosis and apoptosis vs. pro-excitotoxic outcome of NMDAR stimulation, NMDAR modulators could be developed that selectively block the cell death enhancing pro-survival signaling or synaptic plasticity mediated by NMDAR. Among these modulators, a role is emerging for the enzyme serine racemase (SR) that synthesizes D-serine, a key co-agonist with glutamate at NMDAR. This review summarizes the experimental evidence from “in vitro” neuronal cultures—with special emphasis on cerebellar granule neurons (CGNs)—and “in vivo” models of neurodegeneration, where the dual role of the SR/D-serine pathway as a master regulator of apoptosis and the apoptosis-necrosis shift will be discussed.
Collapse
Affiliation(s)
- Nadia Canu
- Dipartimento di Medicina dei Sistemi, Università degli Studi di Roma Roma, Italy ; Istituto di Biologia Cellulare e Neurobiologia, Consiglio Nazionale delle Ricerche Roma, Italy
| | - Maria Teresa Ciotti
- Istituto di Biologia Cellulare e Neurobiologia, Consiglio Nazionale delle Ricerche Roma, Italy
| | - Loredano Pollegioni
- Dipartimento di Biotecnologie e Scienze della Vita, Università degli Studi dell'Insubria Varese, Italy ; Centro Interuniversitario di Ricerca in Biotecnologie Proteiche "The Protein Factory," Politecnico di Milano, ICRM-CNR Milano and Università degli studi dell'Insubria Milano, Italy
| |
Collapse
|
3
|
Magnifico S, Saias L, Deleglise B, Duplus E, Kilinc D, Miquel MC, Viovy JL, Brugg B, Peyrin JM. NAD+ acts on mitochondrial SirT3 to prevent axonal caspase activation and axonal degeneration. FASEB J 2013; 27:4712-22. [PMID: 23975935 DOI: 10.1096/fj.13-229781] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In chronic degenerative syndromes, neuronal death occurs over long periods, during which cells progressively lose their axons and, ultimately, their cell bodies. Although apoptosis is recognized as a key event in neuronal death, the molecular mechanisms involved in CNS axons degeneration are poorly understood. Due to the highly polarized phenotypes of CNS neurons, the different neuronal subcompartments are likely to be targeted by light repetitive and localized aggression. Such locally initiated deleterious signal transduction pathways could theoretically spread through the cytoplasm. However, where axon-degenerative signals initiate, what these early signals are, and how they lead to axon degeneration are unanswered questions that limit our understanding of neurodegenerative diseases and our ability to identify novel therapeutic targets. Using a microfluidic culture device adapted to CNS primary neurons, allowing specific access to the axonal and somatodendritic compartments, we analyzed the molecular pathways involved in axonal degeneration of differentiated neurons. We show here that local application of proapoptotic stimuli on the somatodentritic compartment triggers a dying-back pattern involving caspase-dependent axonal degeneration. Using complementary pharmacological and genetic approaches, we further demonstrate that NAD(+) and grape wine polyphenols prevent axonal apoptosis and act via mitochondrial SirT3 activation in axons.
Collapse
Affiliation(s)
- Sébastien Magnifico
- 1Neurobiologie des Processus Adaptatifs, CNRS UMR 7102, Université Pierre et Marie Curie, 9 Quai St.-Bernard, Bât.B, 6ème étage, 75005 Paris, France.
| | | | | | | | | | | | | | | | | |
Collapse
|
4
|
Nerve growth factor and Alzheimer's disease: new facts for an old hypothesis. Mol Neurobiol 2012; 46:588-604. [PMID: 22940884 DOI: 10.1007/s12035-012-8310-9] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2012] [Accepted: 07/12/2012] [Indexed: 01/10/2023]
Abstract
Understanding sporadic Alzheimer's disease (AD) onset and progression requires an explanation of what triggers the common core of abnormal processing of the amyloid precursor protein and tau processing. In the quest for upstream drivers of sporadic, late-onset AD neurodegeneration, nerve growth factor (NGF) has a central role. Initially connected to AD on a purely correlative basis, because of its neurotrophic actions on basal forebrain cholinergic neurons, two independent lines of research, reviewed in this article, place alterations of NGF processing and signaling at the center stage of a new mechanism, leading to the activation of amyloidogenesis and tau processing. Thus, experimental studies on NGF deficit induced neurodegeneration in transgenic mice, as well as the mechanistic studies on the anti-amyloidogenic actions of NGF/TrkA signaling in primary neuronal cultures demonstrated a novel causal link between neurotrophic signaling deficits and Alzheimer's neurodegeneration. Around these results, a new NGF hypothesis can be built, with neurotrophic deficits of various types representing an upstream driver of the core AD triad pathology. According to the new NGF hypothesis for AD, therapies aimed at reestablishing a correct homeostatic balance between ligands (and receptors) of the NGF pathway appear to have a clear and strong rationale, not just as long-term cholinergic neuroprotection, but also as a truly disease-modifying approach.
Collapse
|
5
|
Marolda R, Ciotti MT, Matrone C, Possenti R, Calissano P, Cavallaro S, Severini C. Substance P activates ADAM9 mRNA expression and induces α-secretase-mediated amyloid precursor protein cleavage. Neuropharmacology 2012; 62:1954-63. [PMID: 22244942 DOI: 10.1016/j.neuropharm.2011.12.025] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Revised: 12/13/2011] [Accepted: 12/21/2011] [Indexed: 01/08/2023]
Abstract
Altered levels of Substance P (SP), a neuropeptide endowed with neuroprotective and anti-apoptotic properties, were found in brain areas and spinal fluid of Alzheimer's disease (AD) patients. One of the hallmarks of AD is the abnormal extracellular deposition of neurotoxic beta amyloid (Aβ) peptides, derived from the proteolytic processing of amyloid precursor protein (APP). In the present study, we confirmed, the neurotrophic action of SP in cultured rat cerebellar granule cells (CGCs) and investigated its effects on APP metabolism. Incubation with low (5 mM) potassium induced apoptotic cell death of CGCs and amyloidogenic processing of APP, whereas treatment with SP (200 nM) reverted these effects via NK1 receptors. The non-amyloidogenic effect of SP consisted of reduction of Aβ(1-42), increase of sAPPα and enhanced α-secretase activity, without a significant change in steady-state levels of cellular APP. The intracellular mechanisms whereby SP alters APP metabolism were further investigated by measuring mRNA and/or steady-state protein levels of key enzymes involved with α-, β- and γ-secretase activity. Among them, Adam9, both at the mRNA and protein level, was the only enzyme to be significantly down-regulated following the induction of apoptosis (K5) and up-regulated after SP treatment. In addition to its neuroprotective properties, this study shows that SP is able to stimulate non-amyloidogenic APP processing, thereby reducing the possibility of generation of toxic Aβ peptides in brain.
Collapse
Affiliation(s)
- R Marolda
- Institute of Cell Biology and Neurobiology, CNR, Via del Fosso di Fiorano, 65, 00143 Rome, Italy
| | | | | | | | | | | | | |
Collapse
|
6
|
Collombet JM. Nerve agent intoxication: Recent neuropathophysiological findings and subsequent impact on medical management prospects. Toxicol Appl Pharmacol 2011; 255:229-41. [DOI: 10.1016/j.taap.2011.07.003] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Revised: 07/07/2011] [Accepted: 07/08/2011] [Indexed: 01/14/2023]
|
7
|
Calissano P, Matrone C, Amadoro G. Apoptosis and in vitro Alzheimer disease neuronal models. Commun Integr Biol 2011; 2:163-9. [PMID: 19513272 DOI: 10.4161/cib.7704] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2008] [Accepted: 12/23/2008] [Indexed: 11/19/2022] Open
Abstract
Alzheimer disease (AD) is a human neurodegenerative disease characterized by co-existence of extracellular senile plaques (SP) and neurofibrillary tangles (NFT) associated with an extensive neuronal loss, primarily in the cerebral cortex and hippocampus. Several studies suggest that caspase(s)-mediated neuronal death occurs in cellular and animal AD models as well as in human brains of affected patients, although an etiologic role of apoptosis in such neurodegenerative disorder is still debated. This review summarizes the experimental evidences corroborating the possible involvement of apoptosis in AD pathogenesis and discusses the usefulness of ad hoc devised in vitro approaches to study how caspase(s), amyloidogenic processing and tau metabolism might reciprocally interact leading to neuronal death.
Collapse
Affiliation(s)
- P Calissano
- Institute of Neurobiology and Molecular Medicine; CNR
| | | | | |
Collapse
|
8
|
Song B, Lai B, Zheng Z, Zhang Y, Luo J, Wang C, Chen Y, Woodgett JR, Li M. Inhibitory phosphorylation of GSK-3 by CaMKII couples depolarization to neuronal survival. J Biol Chem 2010; 285:41122-34. [PMID: 20841359 DOI: 10.1074/jbc.m110.130351] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Glycogen synthase kinase-3 (GSK-3) plays a critical role in neuronal apoptosis. The two mammalian isoforms of the kinase, GSK-3α and GSK-3β, are inhibited by phosphorylation at Ser-21 and Ser-9, respectively. Depolarization, which is vital for neuronal survival, causes both an increase in Ser-21/9 phosphorylation and an inhibition of GSK-3α/β. However, the role of GSK-3 phosphorylation in depolarization-dependent neuron survival and the signaling pathway contributing to GSK-3 phosphorylation during depolarization remain largely unknown. Using several approaches, we showed that both isoforms of GSK-3 are important for mediating neuronal apoptosis. Nonphosphorylatable GSK-3α/β mutants (S21A/S9A) promoted apoptosis, whereas a peptide encompassing Ser-9 of GSK-3β protected neurons in a phosphorylation-dependent manner; these results indicate a critical role for Ser-21/9 phosphorylation on depolarization-dependent neuron survival. We found that Ser-21/9 phosphorylation of GSK-3 was mediated by Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) but not by Akt/PKB, PKA, or p90(RSK). CaMKII associated with and phosphorylated GSK-3α/β. Furthermore, the pro-survival effect of CaMKII was mediated by GSK-3 phosphorylation and inactivation. These findings identify a novel Ca(2+)/calmodulin/CaMKII/GSK-3 pathway that couples depolarization to neuronal survival.
Collapse
Affiliation(s)
- Bin Song
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, 74 Zhongshan Road II, Guangzhou 510080, China
| | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Calissano P, Amadoro G, Matrone C, Ciafrè S, Marolda R, Corsetti V, Ciotti MT, Mercanti D, Di Luzio A, Severini C, Provenzano C, Canu N. Does the term ‘trophic’ actually mean anti-amyloidogenic? The case of NGF. Cell Death Differ 2010; 17:1126-33. [DOI: 10.1038/cdd.2010.38] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
|
10
|
Mellios K, Zacharaki T, Sophou S, Latsari M, Antonopoulos J, Dinopoulos A, Parnavelas J, Dori I. Natural and lesion-induced apoptosis in the rat striatum during development. Brain Res 2009; 1252:30-44. [DOI: 10.1016/j.brainres.2008.10.031] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2008] [Revised: 09/17/2008] [Accepted: 10/06/2008] [Indexed: 12/01/2022]
|
11
|
Collombet JM, Piérard C, Béracochéa D, Coubard S, Burckhart MF, Four E, Masqueliez C, Baubichon D, Lallement G. Long-term consequences of soman poisoning in mice. Behav Brain Res 2008; 191:88-94. [DOI: 10.1016/j.bbr.2008.02.043] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2008] [Accepted: 02/28/2008] [Indexed: 10/22/2022]
|
12
|
Cavallaro S. Neuronal apoptosis revealed by genomic analysis: integrating gene expression profiles with functional information. Neuroinformatics 2007; 5:115-26. [PMID: 17873373 DOI: 10.1007/s12021-007-0006-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/1999] [Revised: 11/30/1999] [Accepted: 11/30/1999] [Indexed: 11/28/2022]
Abstract
Apoptosis is a key physiological response that occurs during development of the nervous system, resulting in the death of nearly half of the embryonic neuronal population. Aberrant apoptotic mechanisms are thought to contribute significantly to many neurological disorders including Alzheimer's disease. Although many experiments in the past have demonstrated the requirement of de novo gene expression during neuronal apoptosis, the complete spectrum of genes involved in distinct temporal domains is mostly unknown. To begin a comprehensive survey of the gene-based molecular mechanisms that underlie neuronal apoptosis, we have used the unprecedented experimental opportunities that genome sequences and the development of DNA microarray technology now provide to perform genome-wide expression analysis in different paradigms of neuronal apoptosis. In order to extract knowledge from gene expression information we have developed new informatics applications that enable clustering methods based on semantic characteristics, such as gene ontologies. This review will highlight the use of a genomic approach to identify the molecular program underlying neuronal apoptosis and illustrate how a semantic clustering method can be useful to extract more knowledge from microarray data.
Collapse
Affiliation(s)
- Sebastiano Cavallaro
- Istituto di Scienze Neurologiche, CNR, Viale Regina Margherita 6, Catania, Italy.
| |
Collapse
|
13
|
Atlante A, Bobba A, de Bari L, Fontana F, Calissano P, Marra E, Passarella S. Caspase-dependent alteration of the ADP/ATP translocator triggers the mitochondrial permeability transition which is not required for the low-potassium-dependent apoptosis of cerebellar granule cells. J Neurochem 2006; 97:1166-81. [PMID: 16606362 DOI: 10.1111/j.1471-4159.2006.03820.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
We investigated ADP/ATP exchange mediated by the adenine nucleotide translocator and opening of the mitochondrial permeability transition pore in homogenates from cerebellar granule cells en route to apoptosis induced by low potassium. We showed that, in the first 3 h of apoptosis, when maximum cytochrome c release had already occurred, adenine nucleotide translocator function was impaired owing to the action of reactive oxygen species, but no permeability transition pore opening occurred. Over 3-8 h of apoptosis, the permeability transition pore progressively opened, owing to caspase action, and further ADP/ATP translocator impairment occurred. The kinetics of transport and permeability transition pore opening were inversely correlated, both in the absence and presence of inhibitors of antioxidant and proteolytic systems. We conclude that, en route to apoptosis, alteration of the adenine nucleotide translocator occurs, resulting in permeability transition pore opening. This process depends on the action of caspase on pore component(s) other than the ADP/ATP translocator, because no change in either amount or molecular weight of the latter protein was noted during apoptosis, as measured by western blotting. Cell death occurs via apoptosis in the presence of cyclosporin A, the permeability transition pore inhibitor, thus showing that permeability transition pore opening, not needed for cytochrome c release, is also unnecessary for apoptosis to occur.
Collapse
Affiliation(s)
- Anna Atlante
- Istituto di Biomembrane e Bioenergetica, Consiglio Nazionale delle Ricerche, Bari, Italy
| | | | | | | | | | | | | |
Collapse
|
14
|
Cavallaro S, D'Agata V, Alessi E, Coffa S, Alkon DL, Manickam P, Ciotti MT, Possenti R, Bonini P, Marlier L, Calissano P. Gene expression profiles of apoptotic neurons. Genomics 2004; 84:485-96. [PMID: 15498456 DOI: 10.1016/j.ygeno.2004.04.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2003] [Accepted: 04/11/2004] [Indexed: 10/26/2022]
Abstract
The multigenic program underlying neuronal apoptosis is mostly unknown. To study the program, we used genome-scale screening by oligonucleotide microarrays during serum and potassium deprivation-induced apoptosis of cerebellar granule neurons. From the 8740 genes interrogated by the arrays, 423 genes were found to be regulated at both the transcriptional and the posttranscriptional level and segregated into distinct clusters. Semantic clustering based on gene ontologies showed coordinated expression of genes with common biological functions and metabolic pathways. Among the genes implicated in apoptotic cerebellar granule neurons, 70 were in common with those differentially expressed in cortical neurons exposed to amyloid beta-protein, indicating the existence of common mechanisms responsible for neuronal cell death. Our results offer a genomic view of the changes that accompany neuronal apoptosis and yield new insights into the underlying molecular basis.
Collapse
Affiliation(s)
- Sebastiano Cavallaro
- Institute of Neurological Sciences, Italian National Research Council, 95123 Catania, Italy.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Canu N, Calissano P. In vitro cultured neurons for molecular studies correlating apoptosis with events related to Alzheimer disease. THE CEREBELLUM 2004; 2:270-8. [PMID: 14964686 DOI: 10.1080/14734220310004289] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
This short review analyses the possible molecular events linking a general program of death such as apoptosis to highly specific intracellular pathways involving the function and degradation of two proteins--tau and amyloid precursor protein--which in their aggregated state constitute the hallmark of Alzheimer disease. By surveying the recent studies carried out in 'in vitro' neuronal cultures--with special emphasis to cerebellar granule neurons--the apparent correlation between onset of apoptosis, tau cleavage with formation of potential toxic fragments, and activation of an amyloidogenic route are discussed. Within this framework, proteasomes seem to play a crucial role upstream of the proteolytic cascade involving calpain(s) and caspase(s) by contributing to tau and amyloid precursor protein-altered breakdown and consequent tendency to aggregation of their degradation fragments. Thus, apoptotic death due to altered supply of anti apoptotic agents, neurotrophic factors, deafferentiation or other causes, may constitute a major trigger of the onset of Alzheimer disease.
Collapse
Affiliation(s)
- Nadia Canu
- Department of Neuroscience, University of Tor Vergata, Rome, Italy.
| | | |
Collapse
|
16
|
Atlante A, Bobba A, Calissano P, Passarella S, Marra E. The apoptosis/necrosis transition in cerebellar granule cells depends on the mutual relationship of the antioxidant and the proteolytic systems which regulate ROS production and cytochrome c release en route to death. J Neurochem 2003; 84:960-71. [PMID: 12603821 DOI: 10.1046/j.1471-4159.2003.01613.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
We investigate the death route induced by potassium depletion in cerebellar granule cells in 0-15 h time range and study whether and how mutual relationship occurs between the cell antioxidant and proteolytic system. To achieve this, we incubated cells in the absence or presence of inhibitors of the antioxidant system, including superoxide dismutase and catalase, and of the proteolytic system, consisting of proteasomes and caspases, and investigated whether and how (i) cell survival, (ii) reactive oxygen species (ROS) production and (iii) antioxidant enzyme and caspase-3 activity change as a function of time after the apoptotic stimulus. The involvement of both antioxidant and proteolytic system on cytochrome c release was also investigated. Cell survival was found to increase in the presence of either proteasome or caspase inhibitors. On the contrary, as a result of the antioxidant system impairment, shift from apoptosis to necrosis occurs. We show that the antioxidant system, which exhibits a huge activity increase up to 3 h after apoptosis induction, is subjected to the proteasome-dependent proteolysis and that the increase in the antioxidant system found in the absence of proteasome activity is accompanied by ROS production decrease. Consistently, the early ROS-dependent release of cytochrome c was found to be prevented when the activity of the antioxidant system increased. Finally, caspase-3 activation was prevented by the inhibitors of both antioxidant system and proteasome.
Collapse
Affiliation(s)
- Anna Atlante
- Istituto di Biomembrane e Bioenergetica CNR, Via Amendola 165/A, 70126 Bari, Italy
| | | | | | | | | |
Collapse
|
17
|
Vankirk AM, Byrd CA. Apoptosis following peripheral sensory deafferentation in the olfactory bulb of adult zebrafish. J Comp Neurol 2003; 455:488-98. [PMID: 12508322 DOI: 10.1002/cne.10502] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Removal of the olfactory organ in adult zebrafish results in a significant decrease in volume of the ipsilateral olfactory bulb. The current study investigated the potential role of apoptosis in this phenomenon. It was hypothesized that cells in the adult olfactory bulb normally undergo minimal apoptosis and that apoptosis increases upon removal of sensory stimulation. By using both the terminal transferase-mediated deoxyuridine nick-end labeling method and bis-benzimide labeling, the current study showed that, in the normal adult olfactory bulb, cells exhibiting apoptotic profiles were scarce and were localized to the outer layers of the bulb. However, in deafferented animals, there was a significant increase in the number of apoptotic cells. The apoptotic response occurred in two phases and was confined to the rostral half of the bulb. The first phase of cell death peaked at 1 hour postsurgery. These apoptotic profiles appeared to be primarily nonneuronal in nature, in that they exhibited no immunohistochemical labeling to the neuron-specific protein Hu. The second phase of cell death peaked at 24 hours and declined to normal levels by 1 week. At the 24 hour time point, only a fraction of the apoptotic cells was neuronal in nature. Thus, apoptosis of nonneuronal and neuronal elements accounts for at least part of the deafferentation-induced volume decrease in the zebrafish olfactory bulb. This model of anterograde transneuronal degeneration will be useful in elucidating the afferent signals involved in survival and maintenance of mature brain neurons.
Collapse
Affiliation(s)
- Akiko M Vankirk
- Department of Biological Sciences, Western Michigan University, Kalamazoo, Michigan 49008-5410, USA
| | | |
Collapse
|
18
|
Harris C, Maroney AC, Johnson EM. Identification of JNK-dependent and -independent components of cerebellar granule neuron apoptosis. J Neurochem 2002; 83:992-1001. [PMID: 12421372 DOI: 10.1046/j.1471-4159.2002.01219.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Cerebellar granule neurons grown in high potassium undergo rapid apoptosis when switched to medium containing 5 mm potassium, a stimulus mimicking deafferentation. This cell death can be blocked by genetic deletion of Bax, a member of the pro-apoptotic Bcl-2 family, cycloheximide an inhibitor of macromolecular synthesis or expression of dominant-negative c-jun. These observations suggest that Bax activation is the result of c-jun target gene(s) up-regulation following trophic withdrawal. Candidate genes include the BH3-only Bcl-2 family members Dp5 and Bim. The molecular mechanisms underlying granule cell neuronal apoptosis in response to low potassium were investigated using CEP-1347 (KT7515), an inhibitor of the MLK family of JNKKK. CEP-1347 provided protection of potassium-serum-deprived granule cells, but such neuroprotection was not long term. The incomplete protection was not due to incomplete blockade of the JNK signaling pathway because c-jun phosphorylation as well as induction of c-jun RNA and protein were completely blocked by CEP-1347. Following potassium-serum deprivation the JNKK MKK4 becomes phosphorylated, an event blocked by CEP-1347. Cells that die in the presence of CEP-1347 activate caspases; and dual inhibition of caspases and MLKs has additive, not synergistic, effects on survival. A lack of synergism was also seen with the p38 inhibitor SB203580, indicating that the neuroprotective effect of the JNK pathway inhibitor cannot be explained by p38 activation. Activation of the JNK signaling pathway seems to be a key event in granule cell apoptosis, but these neurons cannot survive long term in the absence of sustained PI3 kinase signaling.
Collapse
Affiliation(s)
- Charles Harris
- Department of Molecular Biology, Washington University School of Medicine, St Louis, Missouri 63110, USA
| | | | | |
Collapse
|
19
|
Abstract
Recent evidence suggests that blockade of normal excitation in the immature nervous system may have profound effects on neuronal survival during the period of natural cell death. Cell loss following depression of electrical activity in the central nervous system (CNS) may explain the neuropsychiatric deficits in humans exposed to alcohol or other CNS depressants during development. Thus, understanding the role of electrical activity in the survival of young neurons is an important goal of modern basic and clinical neuroscience. Here we review the evidence from in vivo and in vitro model systems that electrical activity participates in promoting neuronal survival. We discuss the potential role of moderate elevations of intracellular calcium in promoting survival, and we address the possible ways in which activity and conventional trophic factors may interact.
Collapse
Affiliation(s)
- S Mennerick
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO 63110, USA
| | | |
Collapse
|
20
|
Ohgoh M, Yamazaki K, Ogura H, Nishizawa Y, Tanaka I. Apoptotic cell death of cerebellar granule neurons in genetically ataxia (ax) mice. Neurosci Lett 2000; 288:167-70. [PMID: 10889334 DOI: 10.1016/s0304-3940(00)01213-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
An autosomal recessive neurological mutant, ataxia (ax) mouse, was investigated to determine whether neuronal cell death occurs in the brain. The brains of homozygotes (ax(J)/ax(J)) and phenotypically normal littermates (ax(J)/+ or +/+) aged at 23-38 days were examined by the terminal dUTP nick-end-labeling (TUNEL) method. A few TUNEL-positive cells were observed in the granule cell layer of the cerebellum, the dentate gyrus, and the olfactory bulb of normal mice. In the affected mice, the number of TUNEL-positive cells was significantly increased in the cerebellum, particularly in the granule cell layer, compared to normal littermates. The findings suggest that ax mice will be useful as a model for studies on the genetic basis of apoptotic neuronal cell death.
Collapse
Affiliation(s)
- M Ohgoh
- Tsukuba Research Laboratories, Eisai Co., Ltd., Tokodai, Tsukuba, 300-2635, Ibaraki, Japan
| | | | | | | | | |
Collapse
|