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Roumes H, Goudeneche P, Pellerin L, Bouzier-Sore AK. Resveratrol and Some of Its Derivatives as Promising Prophylactic Treatments for Neonatal Hypoxia-Ischemia. Nutrients 2022; 14:nu14183793. [PMID: 36145168 PMCID: PMC9501144 DOI: 10.3390/nu14183793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 09/08/2022] [Accepted: 09/09/2022] [Indexed: 11/16/2022] Open
Abstract
Due to the rate of occurrence of neonatal hypoxia-ischemia, its neuronal sequelae, and the lack of effective therapies, the development of new neuroprotective strategies is required. Polyphenols (including resveratrol) are molecules whose anti-apoptotic, anti-inflammatory, and anti-oxidative properties could be effective against the damage induced by neonatal hypoxia-ischemia. In this review article, very recent data concerning the neuroprotective role of polyphenols and the mechanisms at play are detailed, including a boost in brain energy metabolism. The results obtained with innovative approaches, such as maternal supplementation at nutritional doses, suggest that polyphenols could be a promising prophylactic treatment for neonatal hypoxia-ischemia.
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Affiliation(s)
- Hélène Roumes
- Centre de Résonance Magnétique des Sysytèmes Biologiques (CRMSB), UMR 5536, University of Bordeaux and CNRS, F-33000 Bordeaux, France
- Correspondence:
| | - Pierre Goudeneche
- Centre de Résonance Magnétique des Sysytèmes Biologiques (CRMSB), UMR 5536, University of Bordeaux and CNRS, F-33000 Bordeaux, France
| | - Luc Pellerin
- Ischémie Reperfusion, Métabolisme et Inflammation Stérile en Transplantation (IRMETIST), Inserm U1313, University of Poitiers and CHU Poitiers, F-86021 Poitiers, France
| | - Anne-Karine Bouzier-Sore
- Centre de Résonance Magnétique des Sysytèmes Biologiques (CRMSB), UMR 5536, University of Bordeaux and CNRS, F-33000 Bordeaux, France
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2
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Mahale A, Kumar R, Sarode LP, Gakare S, Prakash A, Ugale RR. Dapsone prolong delayed excitotoxic neuronal cell death by interacting with proapoptotic/survival signaling proteins. J Stroke Cerebrovasc Dis 2020; 29:104848. [PMID: 32689584 DOI: 10.1016/j.jstrokecerebrovasdis.2020.104848] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Revised: 03/19/2020] [Accepted: 03/25/2020] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Dapsone prevents ischemic injury, inhibits apoptosis and shows functional improvement post-ischemia. However, its effect on proapoptotic or survival proteins in delayed ischemia remains unclear. METHODS Male adult Wistar rats were subjected to middle cerebral artery occlusion (MCAO) for 90 min followed by 24 h of ischemic reperfusion (I/R). Dapsone [9.375 or 12.5 mg/kg, intraperitoneally (IP)] was administered at 3, 6 and 12 h of I/R followed by behavioural assessment, brain infarction, histological alteration and cell viability study. Further, dapsone (25 and 50 µM) was added at 3, 6 and 12 h after L-glutamate (100 µM) in primary cortical culture (DIV 14) and cell viability, cytotoxicity, apoptosis was observed. Proteins expression were observed using immunocytochemistry. All experiments were performed after 24 h of I/R (In-Vivo) and 24 h of recovery post glutamate insult (In-Vitro). RESULTS Reduced brain infarction, improved neurobehavioural functions in addition to reduction in abnormal morphological structures of ischemic brain and improvement in cell viability was observed with treatment of dapsone (12.5 mg/kg) administered upto 6 h. Similarly, dapsone (25, 50 µM) increased cell survival post glutamate insult in cortical culture (In-vitro). Further, dapsone treatment at delayed hours (6 h) reduced apoptotic nuclei and proapoptotic proteins JNK, PTEN, Calpain, Caspase 3 expression along with activation of prosurvival protein BDNF expression post-glutamate insult. CONCLUSION Our results suggest that dapsone has the potential to limit the neuronal damage post-glutamate insult in delayed hours (6 h) through repressing proapoptotic proteins JNK, PTEN, Calpain, Caspase-3 of cerebral ischemia along with activation of pro-survival protein BDNF.
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Affiliation(s)
- Ashutosh Mahale
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University, Amravati Road, Nagpur 440033, Maharashtra, India
| | - Rakesh Kumar
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University, Amravati Road, Nagpur 440033, Maharashtra, India
| | - Lopmudra P Sarode
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University, Amravati Road, Nagpur 440033, Maharashtra, India
| | - Sukanya Gakare
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University, Amravati Road, Nagpur 440033, Maharashtra, India
| | - Anand Prakash
- Department of Biotechnology, Mahatma Gandhi Central University, Motihari, Bihar, India.
| | - Rajesh R Ugale
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University, Amravati Road, Nagpur 440033, Maharashtra, India.
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3
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Yildiz-Unal A, Korulu S, Karabay A. Neuroprotective strategies against calpain-mediated neurodegeneration. Neuropsychiatr Dis Treat 2015; 11:297-310. [PMID: 25709452 PMCID: PMC4327398 DOI: 10.2147/ndt.s78226] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Calpains are calcium-dependent proteolytic enzymes that have deleterious effects on neurons upon their pathological over-activation. According to the results of numerous studies to date, there is no doubt that abnormal calpain activation triggers activation and progression of apoptotic processes in neurodegeneration, leading to neuronal death. Thus, it is very crucial to unravel all the aspects of calpain-mediated neurodegeneration in order to protect neurons through eliminating or at least minimizing its lethal effects. Protecting neurons against calpain-activated apoptosis basically requires developing effective, reliable, and most importantly, therapeutically applicable approaches to succeed. From this aspect, the most significant studies focusing on preventing calpain-mediated neurodegeneration include blocking the N-methyl-d-aspartate (NMDA)-type glutamate receptor activities, which are closely related to calpain activation; directly inhibiting calpain itself via intrinsic or synthetic calpain inhibitors, or inhibiting its downstream processes; and utilizing the neuroprotectant steroid hormone estrogen and its receptors. In this review, the most remarkable neuroprotective strategies for calpain-mediated neurodegeneration are categorized and summarized with respect to their advantages and disadvantages over one another, in terms of their efficiency and applicability as a therapeutic regimen in the treatment of neurodegenerative diseases.
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Affiliation(s)
- Aysegul Yildiz-Unal
- Department of Molecular Biology and Genetics, Faculty of Science, Muğla Sıtkı Koçman University, Kötekli, Muğla, Turkey
| | - Sirin Korulu
- Department of Molecular Biology and Genetics, Istanbul Arel University, Istanbul Turkey
| | - Arzu Karabay
- Department of Molecular Biology and Genetics, Faculty of Science and Letters, Istanbul Technical University, Maslak, Istanbul, Turkey
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4
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Lewis KJ, Masterman B, Laffafian I, Dewitt S, Campbell JS, Hallett MB. Minimal impact electro-injection of cells undergoing dynamic shape change reveals calpain activation. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1843:1182-7. [PMID: 24607452 DOI: 10.1016/j.bbamcr.2014.02.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Revised: 02/09/2014] [Accepted: 02/28/2014] [Indexed: 10/25/2022]
Abstract
The ability of neutrophils to rapidly change shape underlies their physiological functions of phagocytosis and spreading. A major problem in establishing the mechanism is that conventional microinjection of substances and indicators interferes with this dynamic cell behaviour. Here we show that electroinjection, a "no-touch" point-and-shoot means of introducing material into the cell, is sufficiently gentle to allow neutrophils to be injected whilst undergoing chemokinesis and spreading without disturbing cell shape change behaviour. Using this approach, a fluorogenic calpain-1 selective peptide substrate was introduced into the cytosol of individual neutrophils undergoing shape changes. These data showed that (i) physiologically elevated cytosolic Ca(2+) concentrations were sufficient to trigger calpain-1 activation, blockade of Ca(2+) influx preventing calpain activation and (ii) calpain-1 activity was elevated in spreading neutrophil. These findings provide the first direct demonstration of a physiological role for Ca(2+) elevation in calpain-1 activation and rapid cell spreading. Electroinjection of cells undergoing dynamic shape changes thus opens new avenues of investigation for defining the molecular mechanism underlying dynamic cell shape changes.
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Affiliation(s)
- Kimberley J Lewis
- Neutrophil Signalling Group, Institute of Molecular and Experimental Medicine, School of Medicine, Cardiff University, Heath Park, Cardiff University, Cardiff CF14 4XN, UK
| | - Benjamin Masterman
- Neutrophil Signalling Group, Institute of Molecular and Experimental Medicine, School of Medicine, Cardiff University, Heath Park, Cardiff University, Cardiff CF14 4XN, UK
| | - Iraj Laffafian
- Neutrophil Signalling Group, Institute of Molecular and Experimental Medicine, School of Medicine, Cardiff University, Heath Park, Cardiff University, Cardiff CF14 4XN, UK
| | - Sharon Dewitt
- School of Dentistry, Cardiff University, Heath Park, Cardiff University, Cardiff CF14 4XN, UK
| | - Jennie S Campbell
- Neutrophil Signalling Group, Institute of Molecular and Experimental Medicine, School of Medicine, Cardiff University, Heath Park, Cardiff University, Cardiff CF14 4XN, UK
| | - Maurice B Hallett
- Neutrophil Signalling Group, Institute of Molecular and Experimental Medicine, School of Medicine, Cardiff University, Heath Park, Cardiff University, Cardiff CF14 4XN, UK.
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5
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Gao H, Geng Z. Calpain I activity and its relationship with hippocampal neuronal death in pilocarpine-induced status epilepticus rat model. Cell Biochem Biophys 2013; 66:371-7. [PMID: 23212179 DOI: 10.1007/s12013-012-9476-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
This study aims to establish pilocarpine-induced rat model of status epilepticus (SE), observe the activity of calpain I in the rat hippocampus and the subsequent neuronal death, and explore the relationship between calpain I activity and neuronal death in the hippocampus. Fifty-eight adult male Wistar rats were assigned randomly into either control group (n = 8) or epilepsy group (n = 50). SE was induced in the epilepsy group using pilocarpine. Before the injection, the rats were given atropine sulfate to reduce the side effect of pilocarpine. All rats in the seizure group were grouped into either SE or non-SE, depending on whether they developed convulsive seizures. The rats in SE group were treated with chloral hydrate to stop seizures after 60 min. Control animals were treated with the same dose of 0.9 % saline. All rats were monitored for seizures. At 24 h after SE, the rats' left brain tissues were stained by HE and TUNEL. Neuronal necrosis and apoptosis in the hippocampal CA3 area were observed. Calpain I activity in the right hippocampus was also observed using western blotting. Eighty percent of the rats in the seizure group developed SE, of which 35 % died. No rat died in both the control and non-SE groups. At 24 h after SE, the number of HE-stained neurons decreased (SE group: 55.19 ± 8.23; control group: 102.13 ± 3.73; non-SE group: 101.2 ± 2.86) and the number of TUNEL-positive neurons increased (SE group: 4.91 ± 1.35; non-SE and control group: 0). No obvious changes were observed in the neurons of the control and non-SE group animals. The 76 kDa cleavage of calpain I (the average optical density ratio is 0.096 ± 0.015) emerged in the SE group. Neuronal death has a direct relationship with calpain I activity. There is high success rate and lower death rate for pilocarpine to induce SE. At 24 h after SE, activity of calpain I, neuronal necrosis and apoptosis increased in the hippocampus. Neuronal death has a direct relationship with calpain I activity, which suggests that calpain I plays an important role in neuronal damage during SE.
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Affiliation(s)
- Hua Gao
- Department of Neurology, Shanghai Jiaotong University Affiliated Sixth People's Hospital, 600 Yishan Road, Shanghai, 200233, People's Republic of China
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6
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Páramo B, Montiel T, Hernández-Espinosa DR, Rivera-Martínez M, Morán J, Massieu L. Calpain activation induced by glucose deprivation is mediated by oxidative stress and contributes to neuronal damage. Int J Biochem Cell Biol 2013; 45:2596-604. [PMID: 23994487 DOI: 10.1016/j.biocel.2013.08.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Revised: 07/30/2013] [Accepted: 08/16/2013] [Indexed: 12/16/2022]
Abstract
The mechanisms leading to neuronal death during glucose deprivation have not been fully elucidated, but a role of oxidative stress has been suggested. In the present study we have investigated whether the production of reactive oxygen species during glucose deprivation, contributes to the activation of calpain, a calcium-dependent protease involved in neuronal injury associated with brain ischemia and cerebral trauma. We have observed a rapid activation of calpain, as monitored by the cleavage of the cytoskeletal protein α-spectrin, after glucose withdrawal, which is reduced by inhibitors of xanthine oxidase, phospholipase A2 and NADPH oxidase. Results suggest that phospholipase A2 and NADPH oxidase contribute to the early activation of calpain after glucose deprivation. In particular NOX2, a member of the NADPH oxidase family is involved, since reduced stimulation of calpain activity is observed after glucose deprivation in hippocampal slices from transgenic mice lacking a functional NOX2. We observed an additive effect of the inhibitors of xanthine oxidase and phospholipase A2 on both ROS production and calpain activity, suggesting a synergistic action of these two enzymes. The present results provide new evidence showing that reactive oxygen species stimulate calpain activation during glucose deprivation and that this mechanism is involved in neuronal death.
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Affiliation(s)
- Blanca Páramo
- Departamento de Neuropatología Molecular, División de Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, México, D.F. CP 04510, Mexico.
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7
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Conditional disruption of calpain in the CNS alters dendrite morphology, impairs LTP, and promotes neuronal survival following injury. J Neurosci 2013; 33:5773-84. [PMID: 23536090 DOI: 10.1523/jneurosci.4247-12.2013] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Ubiquitous classical (typical) calpains, calpain-1 and calpain-2, are Ca(+2)-dependent cysteine proteases, which have been associated with numerous physiological and pathological cellular functions. However, a clear understanding of the role of calpains in the CNS has been hampered by the lack of appropriate deletion paradigms in the brain. In this study, we describe a unique model of conditional deletion of both calpain-1 and calpain-2 activities in mouse brain, which more definitively assesses the role of these ubiquitous proteases in brain development/function and pathology. Surprisingly, we show that these calpains are not critical for gross CNS development. However, calpain-1/calpain-2 loss leads to reduced dendritic branching complexity and spine density deficits associated with major deterioration in hippocampal long-term potentiation and spatial memory. Moreover, calpain-1/calpain-2-deficient neurons were significantly resistant to injury induced by excitotoxic stress or mitochondrial toxicity. Examination of downstream target showed that the conversion of the Cdk5 activator, p35, to pathogenic p25 form, occurred only in the presence of calpain and that it played a major role in calpain-mediated neuronal death. These findings unequivocally establish two central roles of calpain-1/calpain-2 in CNS function in plasticity and neuronal death.
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8
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Beyer K, Ariza A. Alpha-Synuclein Posttranslational Modification and Alternative Splicing as a Trigger for Neurodegeneration. Mol Neurobiol 2012; 47:509-24. [DOI: 10.1007/s12035-012-8330-5] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Accepted: 08/13/2012] [Indexed: 12/11/2022]
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9
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Analyses of neuronal damage in excitotoxically lesioned organotypic hippocampal slice cultures. Ann Anat 2010; 192:199-204. [PMID: 20643535 DOI: 10.1016/j.aanat.2010.06.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2010] [Revised: 06/01/2010] [Accepted: 06/08/2010] [Indexed: 11/20/2022]
Abstract
Organotypic hippocampal slice cultures (OHSCs) are widely used to study the mechanisms of neurodegeneration and neuroprotection. However, there are still controversies about the most appropriate method for quantification of neuronal damage. The response to excitotoxic lesions can be determined by propidium iodide (PI) staining, which labels nuclei of degenerating cells. Semiquantitative measurements of PI staining are based on (1) recording of the propidium iodide (PI) fluorescence intensity or (2) counting of PI positive neuronal nuclei. Here, we investigated OHSCs lesioned by the application of increasing NMDA concentrations (10microM, 50microM and 500microM) at 6 days in vitro (div) for 4h or left untreated, respectively. After 9 div, PI staining was performed and the staining determined in the dentate gyrus and cornu ammonis (CA1) by measurement of PI-fluorescence intensity or by counting PI(+)-nuclei with a confocal laser scanning microscope. The fluorescence intensity of lesioned OHSCs did not show a NMDA concentration dependent difference. In contrast, confocal laser scanning microscopy revealed a significant and dose-dependent increase in the number of PI(+)-nuclei. Linear regression analysis showed a high correlation between NMDA concentration and the number of PI(+)-nuclei. A high correlation was also found between the mean number of PI(+)-nuclei determined in every third optical section and that determined in a single mid-stag optical section. The results show that proper analysis of neuronal damage requires counting of PI(+)-nuclei by confocal laser scanning microscopy.
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10
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Affiliation(s)
- Hiroshi MANYA
- Molecular Glycobiology, Tokyo Metropolitan Institute of Gerontology, Foundation for Research on Aging and Promotion of Human Welfare
| | - Keiko AKASAKA-MANYA
- Molecular Glycobiology, Tokyo Metropolitan Institute of Gerontology, Foundation for Research on Aging and Promotion of Human Welfare
| | - Tamao ENDO
- Molecular Glycobiology, Tokyo Metropolitan Institute of Gerontology, Foundation for Research on Aging and Promotion of Human Welfare
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11
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Bevers MB, Lawrence E, Maronski M, Starr N, Amesquita M, Neumar RW. Knockdown of m-calpain increases survival of primary hippocampal neurons following NMDA excitotoxicity. J Neurochem 2009; 108:1237-50. [PMID: 19141074 DOI: 10.1111/j.1471-4159.2008.05860.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The calpain family of cysteine proteases has a well-established causal role in neuronal cell death following acute brain injury. However, the relative contribution of calpain isoforms to the various forms of injury has not been determined as available calpain inhibitors are not isoform-specific. In this study, we evaluated the relative role of m-calpain and mu-calpain in a primary hippocampal neuron model of NMDA-mediated excitotoxicity. Baseline mRNA expression for the catalytic subunit of m-calpain (capn2 ) was found to be 50-fold higher than for the mu-calpain catalytic subunit (capn1) based on quantitative real-time PCR. Adeno-associated viral vectors designed to deliver short hairpin RNAs targeting capn1 or capn2 resulted in 60% and 90% knockdown of message respectively. Knockdown of capn2 but not capn1 increased neuronal survival after NMDA exposure at 21 days in vitro. Nuclear translocation of calpain substrates apoptosis inducing factor, p35/p25 and collapsin response mediator protein (CRMP) 2-4 was not detected after NMDA exposure in this model. However, nuclear translocation of CRMP-1 was observed and was prevented by capn2 knockdown. These findings provide insight into potential mechanisms of calpain-mediated neurodegeneration and have important implications for the development of isoform-specific calpain inhibitor therapy.
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Affiliation(s)
- Matthew B Bevers
- Department of Emergency Medicine, University of Pennsylvania School of Medicine, Philadelphia, 19104, USA
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12
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Del Río P, Massieu L. Mild mitochondrial inhibition in vivo enhances glutamate-induced neuronal damage through calpain but not caspase activation: role of ionotropic glutamate receptors. Exp Neurol 2008; 212:179-88. [PMID: 18495118 DOI: 10.1016/j.expneurol.2008.03.023] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2007] [Revised: 03/18/2008] [Accepted: 03/21/2008] [Indexed: 11/26/2022]
Abstract
Glutamate neurotoxicity is exacerbated when energy metabolism is impaired. In vitro studies show that neuronal death in these conditions is related to mitochondrial dysfunction, ATP depletion, and the loss of calcium homeostasis. We have recently observed that, in vivo, enhancement of glutamate toxicity elicited by previous mitochondrial inhibition does not involve severe ATP depletion, suggesting the involvement of other processes. Factors such as the activation of different proteases may determine the extent and type of cell death. Protease activation might be triggered by internal or external factors, such as mitochondrial damage or the activation of a particular glutamate receptor subtype. In the present study we aimed to investigate whether moderate inhibition of mitochondrial metabolism facilitates glutamate toxicity through caspase-3 or calpain activation, as well as the contribution of NMDA and non-NMDA glutamate ionotropic receptors to this activation. Rats were pre-treated with a subtoxic dose of 3-NP and 4 h later intrastriatally injected with glutamate. Results show that neither of these treatments alone (3-NP or Glu) or in combination (3-NP+Glu) activated caspase-3. Conversely, calpain activity is induced after glutamate injection both in intact and 3-NP pre-treated rats. Inhibition of calpain activity by MDL-28170 significantly prevented striatal damage. NMDA and non-NMDA receptors contributed equally to calpain activation and to the induction of neuronal death. Results suggest that enhancement of glutamate toxicity due to inhibition of mitochondrial metabolism in vivo, does not recruit caspase-dependent apoptosis but favors calpain activation through the stimulation of both subtypes of glutamate ionotropic receptors.
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Affiliation(s)
- Perla Del Río
- Departamento de Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México. México, DF Mexico
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13
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Abstract
The calpain family of proteases is causally linked to postischemic neurodegeneration. However, the precise mechanisms by which calpains contribute to postischemic neuronal death have not been fully elucidated. This review outlines the key features of the calpain system, and the evidence for its causal role in postischemic neuronal pathology. Furthermore, the consequences of specific calpain substrate cleavage at various subcellular locations are explored. Calpain substrates within synapses, plasma membrane, endoplasmic reticulum, lysosomes, mitochondria, and the nucleus, as well as the overall effect of postischemic calpain activity on calcium regulation and cell death signaling are considered. Finally, potential pathways for calpain-mediated neurodegeneration are outlined in an effort to guide future studies aimed at understanding the downstream pathology of postischemic calpain activity and identifying optimal therapeutic strategies.
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Affiliation(s)
- Matthew B Bevers
- Department of Emergency Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104-4283, USA
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14
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Evans JS, Turner MD. Emerging functions of the calpain superfamily of cysteine proteases in neuroendocrine secretory pathways. J Neurochem 2007; 103:849-59. [PMID: 17666040 DOI: 10.1111/j.1471-4159.2007.04815.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The first calpain protease was discovered over 40 years ago now, yet despite the vast amount of literature that has subsequently emerged detailing their involvement in the pathophysiology of a variety of human diseases, it is only in the last decade that calpain-mediated actions along the secretory pathway have begun to emerge. However, the number of secretory pathway substrates identified and their diversity of function continues to grow. This review summarizes our current knowledge of calpain-mediated mechanisms of action that are pertinent to synaptic vesicle assembly and budding, cytoskeletal organization, endosomal recycling, and exocytotic membrane fusion.
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Affiliation(s)
- Joanne S Evans
- Centre for Diabetes and Metabolic Medicine, Institute of Cell and Molecular Science, London, UK
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15
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Glantz SB, Cianci CD, Iyer R, Pradhan D, Wang KK, Morrow JS. Sequential degradation of alphaII and betaII spectrin by calpain in glutamate or maitotoxin-stimulated cells. Biochemistry 2007; 46:502-13. [PMID: 17209560 PMCID: PMC2825692 DOI: 10.1021/bi061504y] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Calpain-catalyzed proteolysis of II-spectrin is a regulated event associated with neuronal long-term potentiation, platelet and leukocyte activation, and other processes. Calpain proteolysis is also linked to apoptotic and nonapoptotic cell death following excessive glutamate exposure, hypoxia, HIV-gp120/160 exposure, or toxic injury. The molecular basis for these divergent consequences of calpain action, and their relationship to spectrin proteolysis, is unclear. Calpain preferentially cleaves II spectrin in vitro in repeat 11 between residues Y1176 and G1177. Unless stimulated by Ca++ and calmodulin (CaM), betaII spectrin proteolysis in vitro is much slower. We identify additional unrecognized sites in spectrin targeted by calpain in vitro and in vivo. Bound CaM induces a second II spectrin cleavage at G1230*S1231. BetaII spectrin is cleaved at four sites. One cleavage only occurs in the absence of CaM at high enzyme-to-substrate ratios near the betaII spectrin COOH-terminus. CaM promotes II spectrin cleavages at Q1440*S1441, S1447*Q1448, and L1482*A1483. These sites are also cleaved in the absence of CaM in recombinant II spectrin fusion peptides, indicating that they are probably shielded in the spectrin heterotetramer and become exposed only after CaM binds alphaII spectrin. Using epitope-specific antibodies prepared to the calpain cleavage sites in both alphaII and betaII spectrin, we find in cultured rat cortical neurons that brief glutamate exposure (a physiologic ligand) rapidly stimulates alphaII spectrin cleavage only at Y1176*G1177, while II spectrin remains intact. In cultured SH-SY5Y cells that lack an NMDA receptor, glutamate is without effect. Conversely, when stimulated by calcium influx (via maitotoxin), there is rapid and sequential cleavage of alphaII and then betaII spectrin, coinciding with the onset of nonapoptotic cell death. These results identify (i) novel calpain target sites in both alphaII and betaII spectrin; (ii) trans-regulation of proteolytic susceptibility between the spectrin subunits in vivo; and (iii) the preferential cleavage of alphaII spectrin vs betaII spectrin when responsive cells are stimulated by engagement of the NMDA receptor. We postulate that calpain proteolysis of spectrin can activate two physiologically distinct responses: one that enhances skeletal plasticity without destroying the spectrin-actin skeleton, characterized by preservation of betaII spectrin; or an alternative response closely correlated with nonapoptotic cell death and characterized by proteolysis of betaII spectrin and complete dissolution of the spectrin skeleton.
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Affiliation(s)
| | | | - Rathna Iyer
- CNS Biology, Pfizer Global Research and Development, 2800 Plymouth Road, Ann Arbor, MI 48105
| | | | - Kevin K.W. Wang
- Departments of Psychiatry and Neuroscience, McKnight Brain Institute of the University of Florida, (P.O.Box100256), Gainesville, FL 32610, USA
| | - Jon S. Morrow
- * To whom correspondence should be addressed. tel: 203-785-3624 Fax 203-785-7037 E-mail:
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16
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Hassen GW, Feliberti J, Kesner L, Stracher A, Mokhtarian F. A novel calpain inhibitor for the treatment of acute experimental autoimmune encephalomyelitis. J Neuroimmunol 2006; 180:135-46. [PMID: 17007940 DOI: 10.1016/j.jneuroim.2006.08.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2006] [Revised: 08/08/2006] [Accepted: 08/14/2006] [Indexed: 02/06/2023]
Abstract
Aberrant activation of calpain plays a key role in the pathophysiology of several neurodegenerative disorders. Calpain is increasingly expressed in inflammatory cells in EAE and is significantly elevated in the white matter of patients with multiple sclerosis, thus calpain inhibition could be a target for therapeutic intervention. The experiments reported here employed a myelin oligodendrocyte glycoprotein-induced disease model in C57Bl/6 mice (EAE) and a novel calpain inhibitor, targeted to nervous tissue. CYLA was found to reduce clinical signs of EAE and prevent demyelination and inflammatory infiltration in a dose- and time-dependent manner. Oral administration of the diacetal prodrug was equally effective.
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MESH Headings
- Acute Disease/therapy
- Animals
- Autoimmunity/drug effects
- Autoimmunity/immunology
- Calpain/antagonists & inhibitors
- Calpain/immunology
- Calpain/metabolism
- Central Nervous System/drug effects
- Central Nervous System/immunology
- Central Nervous System/physiopathology
- Chemotaxis, Leukocyte/drug effects
- Chemotaxis, Leukocyte/immunology
- Disease Models, Animal
- Dose-Response Relationship, Drug
- Encephalomyelitis, Autoimmune, Experimental/drug therapy
- Encephalomyelitis, Autoimmune, Experimental/immunology
- Encephalomyelitis, Autoimmune, Experimental/physiopathology
- Enzyme Inhibitors/pharmacology
- Enzyme Inhibitors/therapeutic use
- Female
- Immunosuppression Therapy/methods
- Inflammation Mediators/immunology
- Inflammation Mediators/pharmacology
- Mice
- Mice, Inbred C57BL
- Myelin Proteins
- Myelin-Associated Glycoprotein/immunology
- Myelin-Associated Glycoprotein/pharmacology
- Myelin-Oligodendrocyte Glycoprotein
- Nerve Fibers, Myelinated/drug effects
- Nerve Fibers, Myelinated/immunology
- Nerve Fibers, Myelinated/pathology
- Oligopeptides/pharmacology
- Oligopeptides/therapeutic use
- Spinal Cord/drug effects
- Spinal Cord/pathology
- Spinal Cord/physiopathology
- Time Factors
- Treatment Outcome
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17
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Lynch G, Rex CS, Gall CM. Synaptic plasticity in early aging. Ageing Res Rev 2006; 5:255-80. [PMID: 16935034 DOI: 10.1016/j.arr.2006.03.008] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2006] [Accepted: 03/30/2006] [Indexed: 01/25/2023]
Abstract
Studies of how aging affects brain plasticity have largely focused on old animals. However, deterioration of memory begins well in advance of old age in animals, including humans; the present review is concerned with the possibility that changes in synaptic plasticity, as found in the long-term potentiation (LTP) effect, are responsible for this. Recent results indicate that impairments to LTP are in fact present by early middle age in rats but only in certain dendritic domains. The search for the origins of these early aging effects necessarily involves ongoing analyses of how LTP is induced, expressed, and stabilized. Such work points to the conclusion that cellular mechanisms responsible for LTP are redundant and modulated both positively and negatively by factors released during induction of potentiation. Tests for causes of the localized failure of LTP during early aging suggest that the problem lies in excessive activity of a negative modulator. The view of LTP as having redundant and modulated substrates also suggests a number of approaches for reversing age-related losses. Particular attention will be given to the idea that induction of brain-derived neurotrophic factor, an extremely potent positive modulator, can be used to provide long periods of normal plasticity with very brief pharmacological interventions. The review concludes with a consideration of how the selective, regional deficits in LTP found in early middle age might be related to the global phenomenon of brain aging.
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Affiliation(s)
- Gary Lynch
- Department of Psychiatry and Human Behavior, Gillespie Neuroscience Research Facility, University of California at Irvine, Irvine, CA 92697, USA.
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18
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Jourdi H, Lu X, Yanagihara T, Lauterborn JC, Bi X, Gall CM, Baudry M. Prolonged positive modulation of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors induces calpain-mediated PSD-95/Dlg/ZO-1 protein degradation and AMPA receptor down-regulation in cultured hippocampal slices. J Pharmacol Exp Ther 2005; 314:16-26. [PMID: 15784649 DOI: 10.1124/jpet.105.083873] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Prolonged exposure of cultured hippocampal slices to CX614 [2H,3H,6aH-pyrrolidino[2'',1''-3',2']1,3-oxazino[6',5'-5,4]-benzo[e]1,4-dioxan 10-one], a positive alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor (AMPAr) modulator, decreases receptor response to synaptic stimulation, an effect that could reflect reduced receptor expression. The present study investigates this down-regulation and its underlying mechanisms using cultured rat hippocampal slices. Chronic treatment with CX614 gradually reduced levels of glutamate receptor (GluR)1 and GluR2/3 AMPAr subunits and of their anchoring proteins synapse-associated protein 97 (SAP97) and glutamate receptor interacting protein 1 (GRIP1) through 48 h. Decline in SAP97 and GRIP1 levels was associated with increased abundance of lower molecular weight bands, suggesting degradation of these proteins. CX614 effects were partially reversible after drug removal. GluR1 and GluR2/3 down-regulation and their slow recovery were associated with similar changes in SAP97 and GRIP1 levels. Treatment with CX614 for 48 h significantly reduced AMPAr mRNA levels in hippocampus, whereas 8-h exposure did not. Blockade of ionotropic glutamate receptors prevented CX614-induced decrease in AMPAr subunits and mRNA, with regional selectivity, although an AMPAr blocker was more efficacious than an N-methyl-D-aspartate receptor blocker. Blockade of calpain activity reduced CX614-induced degradation of SAP97 and GRIP1 and prevented decreases in AMPAr subunit but not mRNA levels. Treatment with CX614 alone or in combination with glutamate receptor blockers or calpain inhibitor III did not modify lactate dehydrogenase release into culture medium, implying the absence of cell toxicity. We conclude that CX614-induced AMPAr protein loss is primarily mediated by AMPAr activation and involves calpain-dependent proteolysis of SAP97 and GRIP1. CX614-induced suppression of AMPAr gene expression is, however, calpain-independent, and all these effects are not associated with cell damage.
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Affiliation(s)
- Hussam Jourdi
- Neuroscience Program and Department of Biology, University of Southern California, Los Angeles, CA 90089-2520, USA
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19
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Kawamura M, Nakajima W, Ishida A, Ohmura A, Miura S, Takada G. Calpain inhibitor MDL 28170 protects hypoxic–ischemic brain injury in neonatal rats by inhibition of both apoptosis and necrosis. Brain Res 2005; 1037:59-69. [PMID: 15777753 DOI: 10.1016/j.brainres.2004.12.050] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2004] [Revised: 12/13/2004] [Accepted: 12/17/2004] [Indexed: 11/29/2022]
Abstract
MDL 28170 is a CNS-penetrating calpain inhibitor, and we examined the effects of MDL 28170 on hypoxic-ischemic brain injury in immature brain using the Rice-Vannucci model. Immediately after hypoxic exposure, 24 mg/kg of MDL 28170 was injected intraperitoneally as an initial dose, followed by 12 mg/kg every 4 h for a total dose of 60 mg/kg over 12 h post-HI. A vehicle control group received peanut oil injection instead. Macroscopic evaluation of brain injury revealed the neuroprotective effect of MDL 28170 after 12 h post-HI. Neuropathological quantitative analysis of cell death showed that MDL 28170 significantly decreased the number of necrotic cells in all the examined regions except for cingular cortex, and the number of apoptotic cells in caudate putamen, parietal cortex, hippocampus CA1, and laterodorsal thalamus. Western blots showed that MDL 28170 suppressed 145/150 kDa subunits of alpha-spectrin breakdown products (SBDP) in cortex, hippocampus, thalamus, and striatum, and also 120-kDa subunit of SBDP in all regions except for striatum. This suggests that MDL 28170 inhibited activation of calpain and caspase-3, respectively. Our results indicate that post-hypoxic MDL 28170 injection is neuroprotective in HI newborn rat brain by decreasing both necrosis and apoptosis. SBDP expression also suggests that MDL 28170 injection inhibits both calpain and caspase-3 activation after HI insult.
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Affiliation(s)
- Masanari Kawamura
- Department of Pediatrics, Akita University School of Medicine, 1-1-1 Hondo, Akita 010-8543, Japan
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20
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Abstract
Numerous lines of evidence demonstrate that calpains, a family of 14 Ca(2+)-activated neutral cysteine proteases, are involved in oncotic cell death in a variety of models. At this time, the biochemistry of most calpains and the specific roles of different calpains in physiology and pathology remain to be determined. A number of calpain substrates have been identified in cellular systems, including cytoskeletal proteins, and recent studies suggest that calpains mediate the increase in plasma membrane permeability to ions and the progressive breakdown of the plasma membrane observed in oncosis through the proteolysis of cystokeletal and plasma membrane proteins. Further, a number of reports provide evidence that the mitochondrial dysfunction observed in oncosis may be mediated by a mitochondrial calpain of unknown identity. Finally, a number of diverse calpain inhibitors have been developed that show cytoprotective properties in cellular systems and in vivo following diverse insults. It is suggested that future research be directed toward elucidation of the role(s) of specific calpain isozymes in physiological and pathological conditions; identifying and linking specific calpain substrates with altered cellular functions; and developing cell-permeable, potent, isozyme-selective calpain inhibitors.
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Affiliation(s)
- Xiuli Liu
- Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA.
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21
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Kondratyev A, Gale K. Latency to onset of status epilepticus determines molecular mechanisms of seizure-induced cell death. ACTA ACUST UNITED AC 2004; 121:86-94. [PMID: 14969739 DOI: 10.1016/j.molbrainres.2003.11.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/13/2003] [Indexed: 11/16/2022]
Abstract
The molecular mechanisms mediating degeneration in response to neuronal insults, including damage evoked by prolonged seizure activity, show substantial variability across laboratories and injury models. Here we investigate the extent to which the proportion of cell death occurring by apoptotic vs. necrotic mechanisms may be shifted by changing the temporal parameters of the insult. In initial studies with continuous seizures (status epilepticus, SE), signs of apoptotic degeneration were most clearly observed when SE occurred following a long latency (>86 min) after injection of kainic acid as compared with a short-latency SE (<76 min). Therefore, in this study we directly compared short- with long-latency SE for the expression of molecular markers for apoptosis and necrosis in an especially vulnerable brain region (rhinal cortex). Molecular markers of apoptosis (DNA fragmentation, cleavage of ICAD, an inhibitor of "caspase-activated DNase" (CAD), and prevalence of a caspase-generated fragment of alpha-spectrin) were detected following long-latency SE. Short-latency SE resulted in expression of predominantly necrotic features of cell death, such as "non-ladder" pattern of genomic DNA degradation, prevalence of a calpain-generated alpha-spectrin fragment, and absence of ICAD cleavage. Silver staining revealed no significant difference in the extent and spatial distribution of degeneration between long- or short-latency SE. These data indicate that the latency to onset of SE determines the extent to which apoptotic or necrotic mechanisms contribute to the degeneration following SE. The presence of a long latency period, during which multiple brief seizure episodes may occur, favors the occurrence of apoptotic cell death. It is possible that the absence of such "preconditioning" period in short-latency SE favors predominantly necrotic profile.
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Affiliation(s)
- Alexei Kondratyev
- Department of Pharmacology, Georgetown University, Washington, DC, USA.
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22
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Ekdahl CT, Zhu C, Bonde S, Bahr BA, Blomgren K, Lindvall O. Death mechanisms in status epilepticus-generated neurons and effects of additional seizures on their survival. Neurobiol Dis 2004; 14:513-23. [PMID: 14678767 DOI: 10.1016/j.nbd.2003.08.022] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Status epilepticus (SE) increases neurogenesis in the subgranular zone (SGZ) of the adult dentate gyrus, but many of the newborn cells die, partly through caspase-induced apoptosis. Here we provide immunohistochemical evidence indicating that the caspase-evoked death of the new neurons involves the mitochondrial but not the death-receptor-mediated pathway. Cytochrome c released from mitochondria was found in a subset of progenitor cell progeny, while Fas ligand and tumor necrosis factor 1 receptor-associated domain as well as the mitochondria-related, caspase-independent apoptosis-inducing factor were not detected. We also show that additional seizures, induced at different stages during neuronal differentiation of progenitor cell progeny following SE, neither potentiate cell death mechanisms in the SGZ nor compromise the survival of the new cells. Thus, we found similar expression of cytochrome c, active caspase-3, caspase-cleaved PARP, and TUNEL/Hoechst-positive DNA fragmentation, as well as numbers of new cells in the SGZ in rats exposed to additional seizures at days 6 and 7 or days 33 and 34 following SE as in control animals only subjected to SE. We propose that the degree of survival of newly generated neurons is determined primarily by the initial SE insult and the ensuing pathology in the tissue environment, whereas spontaneous seizures play a minor role.
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Affiliation(s)
- Christine T Ekdahl
- Section of Restorative Neurology, Wallenberg Neuroscience Center, BMC A11, SE-221 84 Lund, Sweden.
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23
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Mittoo S, Sundstrom LE, Bradley M. Synthesis and evaluation of fluorescent probes for the detection of calpain activity. Anal Biochem 2003; 319:234-8. [PMID: 12871716 DOI: 10.1016/s0003-2697(03)00324-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Two new probes for the detection of calpain I activity based on fluorescence resonance energy transfer technology have been synthesized and evaluated. The probes incorporated the cleavage site present in alpha-spectrin, a naturally occurring substrate of calpain I. The design of the internally quenched substrates is such that the calpain-sensitive bond of the peptides (between the Tyr-Gly residues) is located centrally between the donor and the quencher chromophores. The calpain assay protocol is capable of detecting enzymatic activity in the nanomolar region.
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Affiliation(s)
- Stifun Mittoo
- Department of Chemistry, University of Southampton, Highfield, UK
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24
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Mishizen-Eberz AJ, Guttmann RP, Giasson BI, Day GA, Hodara R, Ischiropoulos H, Lee VMY, Trojanowski JQ, Lynch DR. Distinct cleavage patterns of normal and pathologic forms of alpha-synuclein by calpain I in vitro. J Neurochem 2003; 86:836-47. [PMID: 12887682 DOI: 10.1046/j.1471-4159.2003.01878.x] [Citation(s) in RCA: 128] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Parkinson's disease (PD) is characterized by fibrillary neuronal inclusions called Lewy bodies (LBs) consisting largely of alpha-synuclein (alpha-syn), the protein mutated in some patients with familial PD. The mechanisms of alpha-syn fibrillization and LB formation are unknown, but may involve aberrant degradation or turnover. We examined the ability of calpain I to cleave alpha-syn in vitro. Calpain I cleaved wild-type alpha-syn predominantly after amino acid 57 and within the non-amyloid component (NAC) region. In contrast, calpain I cleaved fibrillized alpha-syn primarily in the region of amino acid 120 to generate fragments like those that increase susceptibility to dopamine toxicity and oxidative stress. Further, while calpain I cleaved wild-type alpha-syn after amino acid 57, this did not occur in mutant A53T alpha-syn. This paucity of proteolysis could increase the stability of A53T alpha-syn, suggesting that calpain I might protect cells from forming LBs by specific cleavages of soluble wild-type alpha-syn. However, once alpha-syn has polymerized into fibrils, calpain I may contribute to toxicity of these forms of alpha-syn by cleaving at aberrant sites within the C-terminal region. Elucidating the role of calpain I in the proteolytic processing of alpha-syn in normal and diseased brains may clarify mechanisms of neurodegenerative alpha-synucleinopathies.
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25
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Pang Z, Bondada V, Sengoku T, Siman R, Geddes JW. Calpain facilitates the neuron death induced by 3-nitropropionic acid and contributes to the necrotic morphology. J Neuropathol Exp Neurol 2003; 62:633-43. [PMID: 12834108 DOI: 10.1093/jnen/62.6.633] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
3-Nitropropionic acid (3NP), an irreversible inhibitor of succinate dehydrogenase, has been used to model features of neurodegenerative disorders including Huntington disease, as well as acute neuronal insults such as cerebral ischemia. 3NP induces rapid necrosis and delayed apoptosis in primary cultures of rat hippocampal neurons. Low levels of extracellular glutamate shift the cell death mechanism to necrosis, whereas antagonism of NMDA receptors results in predominately apoptotic death. In the present study, the involvement of cysteine proteases in the morphologic and biochemical alterations accompanying 3NP-induced neuron death was investigated. Immunoblots of spectrin breakdown products indicated Ca(2+)-dependent cysteine protease (calpain) activation within the 8 hours of 3NP administration, whereas caspase-3 activation was not evident until 16 to 48 hours after treatment. The NMDA receptor antagonist MK-801 (dizocilpine) decreased 3NP-induced calpain activity, but did not alter caspase-3 activity. Similar to MK-801, calpain inhibitors (Z-Val-Phe.H and Z-Leu-Phe-CONHEt) shifted the cell death morphology towards apoptosis and delayed, but did not prevent, the 3NP-induced cell death. Together, the results indicate that following 3NP administration, increased calpain activity precedes caspase-3 activation, contributes to the necrotic morphology, and facilitates and accelerates the cell death.
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Affiliation(s)
- Zhen Pang
- Sanders-Brown Center on Aging and Department of Anatomy and Neurobiology, University of Kentucky, Lexington, Kentucky, KY 40536-0230, USA
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26
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Sloane JA, Hinman JD, Lubonia M, Hollander W, Abraham CR. Age-dependent myelin degeneration and proteolysis of oligodendrocyte proteins is associated with the activation of calpain-1 in the rhesus monkey. J Neurochem 2003; 84:157-68. [PMID: 12485412 DOI: 10.1046/j.1471-4159.2003.01541.x] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Myelin provides important insulating properties to axons allowing for propagation of action potentials over large distances at high velocity. Disruption of the myelin sheath could therefore contribute to cognitive impairment, such as that observed during the normal aging process. In the present study, age-related changes in myelin, myelin proteins and oligodendrocyte proteins were assessed in relationship to calpain-1 expression and cognition in the rhesus monkey. Isolation of myelin fractions from brain white matter revealed that as the content of the intact myelin fraction decreased with age, there was a corresponding increase in the floating or degraded myelin fraction, suggesting an increased breakdown of intact myelin with age. Of the myelin proteins examined, only the myelin-associated glycoprotein decreased with age. Levels of the oligodendrocyte-specific proteins 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNPase) and myelin/oligodendrocyte-specific protein (MOSP) increased dramatically in white matter homogenates and myelin with age. Age-related increases in degraded CNPase also were demonstrable in white matter in association with increases in activated calpain-1. Degraded CNPase was also detectable in myelin fractions, with only the floating fraction containing activated calpain-1. The increases in the activated enzyme in white matter were much greater than those found in myelin fractions suggesting a source other than the myelin membrane for the marked overexpression of activated calpain-1 with age. In addition, CNPase was demonstrated to be a substrate for calpain in vitro. In summary, changes in myelin and oligodendrocyte proteins occur with age, and they appear to have a significant relationship to cognitive impairment. The overexpression of CNPase and MOSP suggests new formation of myelin by oligodendrocytes, which may occur in response to myelin degradation and injury caused by proteolytic enzymes such as calpain.
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Affiliation(s)
- J A Sloane
- Department of Pathology, Boston University School of Medicine, Boston, Massachusetts 02118, USA
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27
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Ekdahl CT, Mohapel P, Weber E, Bahr B, Blomgren K, Lindvall O. Caspase-mediated death of newly formed neurons in the adult rat dentate gyrus following status epilepticus. Eur J Neurosci 2002; 16:1463-71. [PMID: 12405959 DOI: 10.1046/j.1460-9568.2002.02202.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A large proportion of cells that proliferate in the adult dentate gyrus under normal conditions or in response to brain insults exhibit only short-term survival. Here, we sought to determine which cell death pathways are involved in the degeneration of newly formed neurons in the rat dentate gyrus following 2 h of electrically induced status epilepticus. We investigated the role of three families of cysteine proteases, caspases, calpains, and cathepsins, which can all participate in apoptotic cell death. Status epilepticus increased the number of bromodeoxyuridine (BrdU)-positive proliferated cells in the subgranular zone of the dentate gyrus. At the time of maximum cell proliferation, immunohistochemical analyses revealed protein expression of active caspase-cleaved poly (ADP-ribose) polymerase (PARP) in approximately 66% of the BrdU-positive cells, while none of them expressed cathepsin B or the 150-kDa calpain-produced fodrin breakdown product. To evaluate the importance of cysteine proteases in regulating survival of the newly formed neurons, we administered intracerebroventricular infusions of a caspase inhibitor cocktail (zVAD-fmk, zDEVD-fmk and zLEHD-fmk) over a 2-week period, sufficient to allow for neuronal differentiation, starting 1 week after the epileptic insult. Increased numbers of cells double-labelled with BrdU and neuron-specific nuclear protein (NeuN) marker were detected in the subgranular zone and granule cell layer of the caspase inhibitor-treated rats. Our data indicate that caspase-mediated cell death pathways are active in progenitor cell progeny generated by status epilepticus and compromise survival during neuronal differentiation.
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Affiliation(s)
- Christine T Ekdahl
- Section of Restorative Neurology, Wallenberg Neuroscience Center, BMC A11, 221 84 Lund, Sweden.
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28
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Manya H, Inomata M, Fujimori T, Dohmae N, Sato Y, Takio K, Nabeshima YI, Endo T. Klotho protein deficiency leads to overactivation of mu-calpain. J Biol Chem 2002; 277:35503-8. [PMID: 12119304 DOI: 10.1074/jbc.m206033200] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The klotho mouse is an animal model that prematurely shows phenotypes resembling human aging. Here we report that in homozygotes for the klotho mutation (kl(-/-)), alpha(II)-spectrin is highly cleaved, even before the occurrence of aging symptoms such as calcification and arteriosclerosis. Because alpha(II)-spectrin is susceptible to proteolysis by calpain, we examined the activation of calpain in kl(-/-) mice. m-Calpain was not activated, but mu-calpain was activated at an abnormally high level, and an endogenous inhibitor of calpain, calpastatin, was significantly decreased. Proteolysis of alpha(II)-spectrin increased with decreasing level of Klotho protein. Similar phenomena were observed in normal aged mice. Our results indicate that the abnormal activation of calpain due to the decrease of Klotho protein leads to degradation of cytoskeletal elements such as alpha(II)-spectrin. Such deterioration may trigger renal abnormalities in kl(-/-) mice and aged mice, but Klotho protein may suppress these processes.
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Affiliation(s)
- Hiroshi Manya
- Glycobiology Research Group, Tokyo Metropolitan Institute of Gerontology, Foundation for Research on Aging and Promotion of Human Welfare, Tokyo 173-0015, Japan
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29
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Liu X, Harriman JF, Schnellmann RG. Cytoprotective properties of novel nonpeptide calpain inhibitors in renal cells. J Pharmacol Exp Ther 2002; 302:88-94. [PMID: 12065704 DOI: 10.1124/jpet.302.1.88] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Calpains are cytosolic, Ca(2+)-activated, neutral cysteine proteases. Rabbit renal proximal tubule (RPT) cells express both mu- and m-calpain. Although multiple calpain inhibitors protect against RPT cell death, most calpain inhibitors lack specificity, membrane permeability, and/or potency. A group of novel catalytic site-directed calpain inhibitors, including chloroacetic acid N'-[6,7-dichloro-4-(4-methoxy-phenyl)-3-oxo-3,4-dihydroquinoxalin-2-yl]hydrazide (SJA7019) and chloroacetic acid N'-(6,7-dichloro-4-phenyl-3-oxo-3,4-dihydroquinoxalin-2-yl) hydrazide (SJA7029), were identified to be potent calpain inhibitors in vitro. The goals of this study were to determine the action of these two compounds on 1) RPT calpain activity using fluorescein isothiocyanate-casein zymography, 2) antimycin A-induced RPT extracellular (45)Ca(2+) influx and cell death, and 3) hypoxia/reoxygenation-induced RPT cellular dysfunction and death. The results showed that the SJA compounds inhibited RPT mu- and m-calpain with equal potency (approximate IC(50), 30 microM) and efficacy, and blocked antimycin A-induced extracellular Ca(2+) influx and cell death. In addition, SJA7029 blocked cell death and allowed the recovery of mitochondrial function and active Na(+) transport in RPTs subjected to hypoxia/reoxygenation. In summary, the SJA compounds 1) were more potent inhibitors of calpains than catalytic site-directed peptide inhibitors in this model, 2) prevented extracellular Ca(2+) influx during the late phase of cell death, and 3) are true cytoprotectants and allow recovery of RPT cellular functions after injury.
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Affiliation(s)
- Xiuli Liu
- Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
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30
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Caba E, Brown QB, Kawasaki B, Bahr BA. Peptidyl alpha-keto amide inhibitor of calpain blocks excitotoxic damage without affecting signal transduction events. J Neurosci Res 2002; 67:787-94. [PMID: 11891793 DOI: 10.1002/jnr.10163] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The cysteine protease calpain is activated by calcium and has a wide range of substrates. Calpain-mediated cellular damage is associated with many neuropathologies, and calpain also plays a role in signal transduction events that are essential for cell maintenance, including the activation of important kinases and transcription factors. In the present study, the hippocampal slice culture was used as a model of excitotoxicity to test whether the neuroprotection elicited by selective calpain inhibition is associated with changes in cell signaling. Peptidyl alpha-keto amide and alpha-keto acid inhibitors reduced both calpain-mediated cytoskeletal damage and the concomitant synaptic deterioration resulting from an N-methyl-D-aspartate exposure. The alpha-keto amide CX295 was protective when infused into slice cultures before or after the excitotoxic episode. The slices protected with CX295 exhibited normal activation levels of mitogen-activated protein kinase and the transcription factor nuclear factor-kappaB. Thus, selective inhibition of calpain provides neuroprotection without influencing critical signaling pathways.
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Affiliation(s)
- Ebru Caba
- Department of Pharmaceutical Sciences and the Neurosciences Program, University of Connecticut, Storrs, Connecticut 06269-2092, USA
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31
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Blomgren K, Zhu C, Wang X, Karlsson JO, Leverin AL, Bahr BA, Mallard C, Hagberg H. Synergistic activation of caspase-3 by m-calpain after neonatal hypoxia-ischemia: a mechanism of "pathological apoptosis"? J Biol Chem 2001; 276:10191-8. [PMID: 11124942 DOI: 10.1074/jbc.m007807200] [Citation(s) in RCA: 362] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The relative contributions of apoptosis and necrosis in brain injury have been a matter of much debate. Caspase-3 has been identified as a key protease in the execution of apoptosis, whereas calpains have mainly been implicated in excitotoxic neuronal injury. In a model of unilateral hypoxia-ischemia in 7-day-old rats, caspase-3-like activity increased 16-fold 24 h postinsult, coinciding with cleavage of the caspase-3 proenzyme and endogenous caspase-3 substrates. This activation was significantly decreased by pharmacological calpain inhibition, using CX295, a calpain inhibitor that did not inhibit purified caspase-3 in vitro. Activation of caspase-3 by m-calpain, but not mu-calpain, was facilitated in a dose-dependent manner in vitro by incubating cytosolic fractions, containing caspase-3 proform, with calpains. This facilitation required the presence of some active caspase-3 and could be abolished by including the specific calpain inhibitor calpastatin. This indicates that initial cleavage of caspase-3 by m-calpain, producing a 29-kDa fragment, facilitates the subsequent cleavage into active forms. This is the first report to our knowledge suggesting a direct link between the early, excitotoxic, calcium-mediated activation of calpain after cerebral hypoxia-ischemia and the subsequent activation of caspase-3, thus representing a tentative pathway of "pathological apoptosis."
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Affiliation(s)
- K Blomgren
- Perinatal Center, Institute of Physiology and Pharmacology, Göteborg University, Sweden.
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Vanderklish PW, Bahr BA. The pathogenic activation of calpain: a marker and mediator of cellular toxicity and disease states. Int J Exp Pathol 2000; 81:323-39. [PMID: 11168679 PMCID: PMC2517738 DOI: 10.1111/j.1365-2613.2000.00169.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2000] [Accepted: 08/14/2000] [Indexed: 11/30/2022] Open
Abstract
Over-activation of calpain, a ubiquitous calcium-sensitive protease, has been linked to a variety of degenerative conditions in the brain and several other tissues. Dozens of substrates for calpain have been identified and several of these have been used to measure activation of the protease in the context of experimentally induced and naturally occurring pathologies. Calpain-mediated cleavage of the cytoskeletal protein spectrin, in particular, results in a set of large breakdown products (BDPs) that are unique in that they are unusually stable. Over the last 15 years, measurements of BDPs in experimental models of stroke-type excitotoxicity, hypoxia/ischemia, vasospasm, epilepsy, toxin exposure, brain injury, kidney malfunction, and genetic defects, have established that calpain activation is an early and causal event in the degeneration that ensues from acute, definable insults. The BDPs also have been found to increase with normal ageing and in patients with Alzheimer's disease, and the calpain activity may be involved in related apoptotic processes in conjunction with the caspase family of proteases. Thus, it has become increasingly clear that regardless of the mode of disturbance in calcium homeostasis or the cell type involved, calpain is critical to the development of pathology and therefore a distinct and powerful therapeutic target. The recent development of antibodies that recognize the site at which spectrin is cleaved has greatly facilitated the temporal and spatial resolution of calpain activation in situ. Accordingly, sensitive spectrin breakdown assays now are utilized to identify potential toxic side-effects of compounds and to develop calpain inhibitors for a wide range of indications including stroke, cerebral vasospasm, and kidney failure.
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Affiliation(s)
- P W Vanderklish
- Department of Neurobiology, Scripps Research Institute, La Jolla, California, USA
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Vanderklish PW, Krushel LA, Holst BH, Gally JA, Crossin KL, Edelman GM. Marking synaptic activity in dendritic spines with a calpain substrate exhibiting fluorescence resonance energy transfer. Proc Natl Acad Sci U S A 2000; 97:2253-8. [PMID: 10688895 PMCID: PMC15787 DOI: 10.1073/pnas.040565597] [Citation(s) in RCA: 135] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Excitatory synaptic activity can evoke transient and substantial elevations of postsynaptic calcium. Downstream effects of elevated calcium include the activation of the calcium-dependent protease calpain. We have developed a reagent that identifies dendritic spines in which calpain has been activated. A fusion protein was expressed that contained enhanced yellow and enhanced cyan fluorescent protein (EYFP and ECFP, respectively) linked by a peptide that included the micro-calpain cleavage site from alpha-spectrin. A PDZ-binding site fused to ECFP anchored this protein to postsynaptic densities. The fusion protein exhibited fluorescence resonance energy transfer (FRET), and diminution of FRET by proteolysis was used to localize calpain activity in situ by fluorescence microscopy. Incubation of the fusion protein with calpain in the presence of calcium resulted in the separation of EYFP and ECFP into monomeric fluorophores. In transiently transfected cell lines and dissociated hippocampal neurons, FRET was diminished by raising intracellular calcium levels with an ionophore or with glutamatergic agonists. Calpain inhibitors blocked these changes. Under control conditions, FRET levels in different dendritic spines of cultured neurons and in hippocampal slices were heterogeneous but showed robust decreases upon treatment with glutamatergic agonists. Immunostaining of cultured neurons with antibodies to a spectrin epitope produced by calpain-mediated digestion revealed an inverse correlation between the amount of FRET present at postsynaptic elements and the concentration of spectrin breakdown products. These results suggest that the FRET methodology identifies sites of synaptically induced calpain activity and that it may be useful in analyzing synapses undergoing changes in efficacy.
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Affiliation(s)
- P W Vanderklish
- Department of Neurobiology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
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Sangerman J, Gard AL, Shah A, Goodman SR. Synthesis, assembly, and turnover of alpha and beta-erythroid and nonerythroid spectrins in rat hippocampal neurons. Brain Res 1999; 849:128-38. [PMID: 10592294 DOI: 10.1016/s0006-8993(99)02026-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The synthesis and turnover of alpha-erythroid, beta-erythroid, alpha-nonerythroid and beta-nonerythroid spectrins was investigated in cultured rat hippocampal neurons. [35S]methionine and subunit specific antibodies were used to label and immunoprecipitate newly synthesized spectrins in 12- to 14-day-old cultures. Synthesis experiments, performed under normal resting conditions, showed that the ratio of newly synthesized alpha-erythroid/beta-erythroid and alpha-nonerythroid/beta-nonerythroid spectrins is 1/1 (mol/mol) both in the soluble and insoluble fractions. Soluble and insoluble alpha and beta erythroid spectrin turn over rapidly (half-life=16-24 min). Soluble nonerythroid alpha-spectrin (half-life=80 min) and beta spectrin (half-life=53 min) turn over more slowly than their insoluble counterparts (30-34 min). The nonerythroid alpha spectrin turnover was significantly different (p<0.05) from the other measurements except for nonerythroid beta spectrin, indicating that these subunits are protected from rapid proteolytic degradation until they are assembled in the membrane skeleton.
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Affiliation(s)
- J Sangerman
- Department of Structural Biology, University of South Alabama College of Medicine, MSB 2042, Mobile, AL, USA
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Hicks PM, Rinker KD, Baker JR, Kelly RM. Homomultimeric protease in the hyperthermophilic bacterium Thermotoga maritima has structural and amino acid sequence homology to bacteriocins in mesophilic bacteria. FEBS Lett 1998; 440:393-8. [PMID: 9872409 DOI: 10.1016/s0014-5793(98)01451-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
A novel homomultimeric protease (> 669 kDa), based on 31 kDa subunits, was purified from cell extracts of the hyperthermophilic bacterium Thermotoga maritima. This protease exhibits activity toward chymotrypsin and trypsin substrates, optimally at 90 degrees C and pH 7.1, and has a half-life of 36 min at 95 degrees C. Transmission electron microscopy established that the protease consists of a large globular assembly which appears circular from the front view. The function of this protease in T. maritima remains unclear, although putative homologs include a 29 kDa antigen from Mycobacterium tuberculosis and a 31 kDa monomer of a high molecular weight bacteriocin produced by Brevibacterium linens [Valdes-Stauber, N. and Scherer, S. (1996) Appl. Environ. Microbiol. 62, 1283-1286]. The relationship of these mesophilic proteins to the T. maritima protease suggests that their antibacterial activity may involve elements of proteolysis, and raises the prospect for antimicrobial ecological strategies in hyperthermophilic niches.
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Affiliation(s)
- P M Hicks
- Department of Chemical Engineering, North Carolina State University, Raleigh 27695-7905, USA
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Hewitt KE, Lesiuk HJ, Tauskela JS, Morley P, Durkin JP. Selective coupling of mu-calpain activation with the NMDA receptor is independent of translocation and autolysis in primary cortical neurons. J Neurosci Res 1998; 54:223-32. [PMID: 9788281 DOI: 10.1002/(sici)1097-4547(19981015)54:2<223::aid-jnr10>3.0.co;2-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Excessive mu-calpain activation has been linked to several cellular pathologies including excitotoxicity and ischemia. In erythrocytes and other non-central nervous system (CNS) cells, calpain activation is thought to occur following a Ca2+-induced translocation of inactive cytosolic enzyme to membranes and subsequent autolysis. In the present report, we show that transiently exposing primary rat cortical neurons to lethal (50 microM) N-methyl-D-aspartic acid (NMDA) caused protracted calpain activation, measured as increased spectrin hydrolysis, but this was independent of translocation or autolysis of the protease. An anti-mu-calpain antibody showed that calpain was largely membrane associated in cortical neurons, and, consequently, neither translocation nor autolysis of the protease was observed following ionomycin or lethal NMDA treatment. By contrast, in rat erythrocytes, calpain was largely cytosolic and underwent rapid translocation and autolysis in response to ionomycin. Calpain-mediated spectrin hydrolysis was specifically coupled to Ca2+ entry through the NMDA receptor because nonspecific Ca2+ influx via ionomycin or KCl-mediated depolarization failed to activate the enzyme. Thus, calpain appears selectively linked to glutamate receptors in cortical neurons and regulated by mechanisms distinct from that occurring in many non-CNS cells. The data suggest that intracellular signals coupled to the NMDA receptor are responsible for activating calpain already associated with cellular membranes in cortical cells.
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Affiliation(s)
- K E Hewitt
- Cellular Neurobiology Group, Institute for Biological Sciences, National Research Council of Canada, University of Ottawa, Ontario
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Abstract
Efforts to characterize long-term potentiation (LTP) and to identify its substrates have led to the discovery of novel synaptic chemistries, computational algorithms, and, most recently, pharmacologies. Progress has also been made in using LTP to develop a "standard model" of how unusual, but physiologically plausible, levels of afferent activity create lasting changes in the operating characteristics of synapses in the cortical telencephalon. Hypotheses of this type typically distinguish induction, expression, and consolidation stages in the formation of LTP. Induction involves a sequence consisting of theta-type rhythmic activity, suppression of inhibitory currents, intense synaptic depolarization, NMDA receptor activation, and calcium influx into dendritic spines. Calcium-dependent lipases, kinases, and proteases have been implicated in LTP induction. Regarding the last group, it has been recently reported that theta pattern stimulation activates calpain and that translational suppression of the protease blocks potentiation. It is thus likely that proteolysis is readily driven by synaptic activity and contributes to structural reorganization. LTP does not interact with treatments that affect transmitter release, has a markedly differential effect on the currents mediated by colocalized AMPA vs NMDA synaptic receptors, changes the waveform of the synaptic current, modifies the effects of drugs that modulate AMPA receptors, and is sensitive to the subunit composition of those receptors. These results indicate that LTP is expressed by changes in AMPA receptor operations. LTP is accompanied by modifications in the anatomy of synapses and spines, something which accounts for its extreme duration (weeks). As with various types of memory, LTP requires about 30 min to consolidate (become resistant to disruption). Consolidation involves adhesion chemistries and, in particular, activation of integrins, a class of transmembrane receptors that control morphology in numerous cell types. Platelet activating factor and adenosine may contribute to consolidation by regulating the engagement of latent integrins. How consolidation stabilizes LTP expression is a topic of intense investigation but probably involves modifications to one or more of the following: membrane environment of AMPA receptors; access of regulatory proteins (e.g., kinases, proteases) to the receptors; receptor clustering; and space available for receptor insertion. Attempts to enhance LTP have focused on the induction phase and resulted in a class of centrally active drugs ("ampakines") that positively modulate AMPA receptors. These compounds promote LTP in vivo and improve the encoding of variety of memory types in animals. Positive results have also been obtained in preliminary studies with humans.
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Affiliation(s)
- G Lynch
- University of California, Irvine, California 92697-3800, USA
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Gitler D, Spira ME. Real time imaging of calcium-induced localized proteolytic activity after axotomy and its relation to growth cone formation. Neuron 1998; 20:1123-35. [PMID: 9655501 DOI: 10.1016/s0896-6273(00)80494-8] [Citation(s) in RCA: 134] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The emergence of a neuronal growth cone from a transected axon is a necessary step in the sequence of events that leads to successful regeneration. Yet, the molecular mechanisms underlying its formation after axotomy are unknown. In this study, we show by real time imaging of the free intracellular Ca2+ concentration, of proteolytic activity, and of growth cone formation that the activation of localized and transient Ca2+-dependent proteolysis is a necessary step in the cascade of events that leads to growth cone formation. Inhibition of this proteolytic activity by calpeptin, a calpain inhibitor, abolishes growth cone formation. We suggest that calpain plays a central role in the reorganization of the axon's cytoskeleton during its transition from a stable differentiated structure into a dynamically extending growth cone.
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Affiliation(s)
- D Gitler
- Department of Neurobiology, Institute of Life Sciences, The Hebrew University of Jerusalem, Israel
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Abstract
In this study, the effects of oxidative stress on calpain-mediated proteolysis and calpain I autolysis in situ were examined. Calpain activity was stimulated in SH-SY5Y human neuroblastoma cells with the calcium ionophore, ionomycin. Calpain-mediated proteolysis of the membrane-permeable fluorescent substrate N-succinyl-L-leucyl-L-leucyl-L-valyl-L-tyrosine-7-amido-4-methylcouma rin, as well as the endogenous protein substrates microtubule-associated protein 2, tau and spectrin, was measured. Oxidative stress, induced by addition of either doxorubicin or 2-mercaptopyridine N-oxide, resulted in a significant decrease in the extent of ionophore-stimulated calpain activity of both the fluorescent compound and the endogenous substrates compared with control, normoxic conditions. Addition of glutathione ethyl ester, as well as other antioxidants, resulted in the retention/recovery of calpain activity, indicating that oxidation-induced calpain inactivation was preventable/reversible. The rate of autolytic conversion of the large subunit of calpain I from 80 to 78 to 76 kDa was decreased during oxidative stress; however, the extent of calpain autolysis was not altered. These data indicate that oxidative stress may reversibly inactivate calpain I in vivo.
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Affiliation(s)
- R P Guttmann
- Department of Psychiatry, University of Alabama at Birmingham, Birmingham, Alabama 35294-0017, USA
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Li HL, Feinstein SI, Liu L, Zimmerman UJ. An antisense oligodeoxyribonucleotide to m-calpain mRNA inhibits secretion from alveolar epithelial type II cells. Cell Signal 1998; 10:137-42. [PMID: 9481489 DOI: 10.1016/s0898-6568(97)00101-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
We investigated the effect of translational suppression of m-calpain on [3H]-phosphatidylcholine (PC) secretion utilising an antisense oligodexoyribonucleotide (oligo) directed against mRNA encoding m-calpain catalytic subunit. Two types of oligo, sense (S) and antisense (AS), to a portion of exon 12 of rat m-calpain catalytic subunit mRNA were tested. Constitutive secretion was decreased by 23% by AS-oligo (1 microM) treatment, while S-oligo (1 microM) had no effect. TPA-stimulated secretion was inhibited about 50-60% by AS-oligo (1-3 microM) and the inhibition was concentration-dependent, while S-oligo (1 microM) only inhibited about 10% of TPA-stimulated secretion. Northern and Western blot analyses revealed that the AS-oligo treatment reduced m-calpain mRNA and protein levels by 32% and 78%, respectively. The data indicate that antisense strategy is effective in suppressing calpain expression and type II cell secretion.
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Affiliation(s)
- H L Li
- Institute for Environmental Medicine, University of Pennsylvania Medical Center, Philadelphia 19104, USA
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Camins A, Sureda FX, Gabriel C, Pallàs M, Escubedo E, Camarasa J. Modulation of neuronal mitochondrial membrane potential by the NMDA receptor: role of arachidonic acid. Brain Res 1997; 777:69-74. [PMID: 9449414 DOI: 10.1016/s0006-8993(97)00947-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Activation of NMDA receptors in dissociated cerebellar granule cells reduced mitochondrial membrane potential (MMP), as measured by rhodamine 123 fluorescence in a flow cytometer. This effect was inhibited by several NMDA-receptor antagonists with the following rank order of potency: MK-801 > PCP > TCP > dextrorphan > dichlorokynurenic acid > D-AP5 > dextromethorphan. Neither spermine nor arcaine modified the NMDA-induced reduction in MMP, whereas ifenprodil and eliprodil inhibited this response in the micromolar range. The mechanism responsible for the alteration of MMP mediated by NMDA was studied. Mepacrine and dibucaine prevented the MMP reduction induced by NMDA, as did W13 (calmodulin antagonist). In contrast, this effect was not blocked by cyclooxygenase or lipooxygenase inhibitors, H7 (a protein kinase C inhibitor) or nitroarginine (nitric oxide synthase inhibitor). These data suggest a direct interaction between NMDA-receptor activation and arachidonic acid formation, and indicate that NMDA receptor-mediated effect on MMP could involve arachidonic acid.
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Affiliation(s)
- A Camins
- Facultat de Farmacia, Universitat de Barcelona, Nucli Universitari de Pedralbes, Spain
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Griffiths R, Malcolm C, Ritchie L, Frandsen A, Schousboe A, Scott M, Rumsby P, Meredith C. Association of c-fos mRNA expression and excitotoxicity in primary cultures of mouse neocortical and cerebellar neurons. J Neurosci Res 1997; 48:533-42. [PMID: 9210523 DOI: 10.1002/(sici)1097-4547(19970615)48:6<533::aid-jnr6>3.0.co;2-b] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The effect of excitatory amino acids (EAAs) on c-fos mRNA expression was studied in primary cultures of mouse cerebellar granule cells and in neocortical neurons after 2 and 7 days in vitro (div). In cultured granule cells at 2 and 7 div, and in cortical neurons at 2 div, exposure to low levels (< or = 10 microM) of a variety of EAAs (viz. glutamate [Glu], S-sulpho-L-cysteine [SC], N-methyl-D-aspartate [NMDA], alpha-amino-3-hydroxy-5-methyl-4-isoxazole [AMPA], and kainate [KA]) resulted in a transient increase in the level of c-fos mRNA which peaked at 30 min but returned to a basal level by 120 min. However, exposure of granule cells (7 div) to high levels (250 microM) of Glu, NMDA, KA, SC and of cortical neurons (7 div) to high levels (250 microM) of Glu, NMDA, KA, SC, or AMPA and to low levels (< or = 10 microM) of Glu and AMPA resulted in a delay in c-fos mRNA induction but a subsequent, progressive increase that was sustained for at least 240 min. Furthermore, this effect was accompanied by a dose-related increase in the release of the cytosolic enzyme, lactate dehydrogenase, used as an indicator of excitotoxicity. A ratio (Q240/30) for the steady-state levels of c-fos mRNA after 30 min and 240 min of exposure to EAAs was determined which showed that Q240/30 >2 correlated reproducibly with excitotoxic cell death, whereas a ratio of < or = 1 correlated with a nonexcitotoxic event. In both cell types at 7 div, coadministration of the selective NMDA receptor antagonist, DL(+/-)-2-amino-5-phosphonopentanoic acid (APV) with cytotoxic levels of Glu 1) protected against EAA-induced neurotoxicity and 2) exhibited a transient c-fos mRNA expression (Q240/30 values approximately 1). In contrast, the AMPA/KA receptor antagonist, 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX), provided no protection against excitotoxicity and had no significant effect on the Glu-induced delay in c-fos mRNA expression. These results suggest that the Q240/30 c-fos mRNA ratio may 1) be used as a predictive index for excitotoxic neuronal death, 2) provide information on the identity of the receptor subtype mediating excitotoxicity in different brain cell types, and 3) aid in establishing the role of excitotoxicity during the development of neurons in vitro.
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Affiliation(s)
- R Griffiths
- Neurochemistry Group, School of Biological and Medical Sciences, University of St. Andrews, Fife, Scotland.
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Suppression of cathepsins B and L causes a proliferation of lysosomes and the formation of meganeurites in hippocampus. J Neurosci 1997. [PMID: 9151717 DOI: 10.1523/jneurosci.17-11-04006.1997] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Cultured hippocampal slices exhibited prominent ultrastructural features of brain aging after exposure to an inhibitor of cathepsins B and L. Six days of treatment with N-CBZ-L-phenylalanyl-L-alanine-diazomethylketone (ZPAD) resulted in a dramatic increase in the number of lysosomes in the perikarya of neurons and glial cells throughout the slices. Furthermore, lysosomes in CA1 and CA3 pyramidal cells were not restricted to the soma but instead were located throughout dendritic processes. Clusters of lysosomes were commonly found within bulging segments of proximal dendrites that were notable for an absence of microtubules and neurofilaments. Although pyknotic nuclei were sometimes encountered, most of the cells in slices exposed to ZPAD for 6 d appeared relatively normal. Slices given 7 d of recovery contained several unique features, compared with those processed immediately after incubation with the inhibitor. Cell bodies of CA1 neurons were largely cleared of the excess lysosomes but had gained fusiform, somatic extensions that were filled with fused lysosomes and related complex, dense bodies. These appendages, similar in form and content to structures previously referred to as "meganeurites," were not observed in CA3 neurons or granule cells. Because meganeurites were often interposed between cell body and axon, they have the potential to interfere with processes requiring axonal transport. It is suggested that inactivation of cathepsins B and L results in a proliferation of lysosomes and that meganeurite generation provides a means of storing residual catabolic organelles. The accumulated material could be eliminated by pinching off the meganeurite but, at least in some cases, this action would result in axotomy. Reduced cathepsin L activity, increased numbers of lysosomes, and the formation of meganeurites are all reported to occur during brain aging; thus, it is possible that the infusion of ZPAD into cultured slices sets in motion a greatly accelerated gerontological sequence.
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Rami A, Ferger D, Krieglstein J. Blockade of calpain proteolytic activity rescues neurons from glutamate excitotoxicity. Neurosci Res 1997; 27:93-7. [PMID: 9089703 DOI: 10.1016/s0168-0102(96)01123-6] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The potential of protease inhibitors E-64, calpain inhibitor I (CPI-I) and MDL28170 to protect hippocampal neurons in an in vitro model of neurotoxicity was investigated. Hippocampal cultures were treated with glutamate, and neurotoxicity was quantified. Glutamate treated cultures exhibited damage to approximately 50% of neurons. In contrast only 20-30% of neurons were damaged in cultures treated with glutamate and calpain inhibitors. E-64 and CPI-I are capable of protecting neurons from injury only in pre-treatment schedule. MDL28170 exhibits a neuroprotective effect in the pre-treatment schedule and also even when given immediately after the cultures had been switched to the glutamate-containing medium. Although the neuroprotective effect of MDL28170 in the postreatment schedule was modest, this supports a strick link between the ability of protease inhibitors to penetrate cellular membranes and their potency of neuroprotection. These data provide evidence that calpain-induced proteolysis is an important pathogenic factor in brain injury and suggest that calpain inhibitors may be considered as a powerful mean to counteract the sequelea of neurotoxicity.
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Affiliation(s)
- A Rami
- Klinikum der Johann Wolfgang Goethe-Universität, Zentrum der Morphologie (Dr. Senckenbergische Anatomie), Frankfurt, Germany
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