The Experts below are selected from a list of 243141 Experts worldwide ranked by ideXlab platform
Francesco Cecconi - One of the best experts on this subject based on the ideXlab platform.
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Caspase-3 in the Central Nervous System: Beyond Apoptosis
Trends in neurosciences, 2012Co-Authors: Marcello D'amelio, Morgan Sheng, Francesco CecconiAbstract:Caspase-3 has been identified as a key mediator of neuronal programmed cell death. This protease plays a central role in the developing nervous system and its activation is observed early in neural tube formation and persists during postnatal differentiation of the neural network. Caspase-3 activation, a crucial event of neuronal cell death program, is also a feature of many chronic neurodegenerative diseases. This traditional apoptotic function of Caspase-3 is challenged by recent studies that reveal new cell death-independent roles for mitochondrial-activated Caspase-3 in neurite pruning and synaptic plasticity. These findings underscore the need for further research into the mechanism of action and functions of Caspase-3 that may prove useful in the development of novel pharmacological treatments for a diverse range of neurological disorders.
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Neuronal Caspase-3 signaling: not only cell death
Cell death and differentiation, 2009Co-Authors: Marcello D'amelio, Virve Cavallucci, Francesco CecconiAbstract:Caspases are a family of cysteinyl aspartate-specific proteases that are highly conserved in multicellular organisms and function as central regulators of apoptosis. A member of this family, Caspase-3, has been identified as a key mediator of apoptosis in neuronal cells. Recent studies in snail, fly and rat suggest that Caspase-3 also functions as a regulatory molecule in neurogenesis and synaptic activity. In this study, in addition to providing an overview of the mechanism of Caspase-3 activation, we review genetic and pharmacological studies of apoptotic and nonapoptotic functions of Caspase-3 and discuss the regulatory mechanism of Caspase-3 for executing nonapoptotic functions in the central nervous system. Knowledge of biochemical pathway(s) for nonapoptotic activation and modulation of Caspase-3 has potential implications for the understanding of synaptic failure in the pathophysiology of neurological disorders. Fine-tuning of Caspase-3 lays down a new challenge in identifying pharmacological avenues for treatment of many neurological disorders.
David M. Holtzman - One of the best experts on this subject based on the ideXlab platform.
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Caspase-3 deficiency during development increases vulnerability to hypoxic–ischemic injury through Caspase-3-independent pathways
Neurobiology of disease, 2006Co-Authors: Tim West, Madeliene Atzeva, David M. HoltzmanAbstract:Abstract Neonatal hypoxia–ischemia (H–I) is a common cause of perinatal morbidity and mortality leading to prominent activation of Caspase-3 in the brain. Previous studies have shown that acute inhibition of Caspase-3 can protect against neonatal H–I in rats. In this study, we investigated brain injury following neonatal H–I in mice deficient in Caspase-3. Wild-type, Caspase-3+/− and Caspase-3−/− mice underwent unilateral carotid ligation at postnatal day (P) 7, followed by 45 min of exposure to 8% oxygen. Surprisingly, tissue loss at P14 was significantly higher in Caspase-3−/− mice when compared to wild-type littermates. As in rats, we found that acute inhibition of Caspase-3 in mice leads to decrease in tissue loss at P14. There was no difference in nuclear morphology, DNA laddering or calpain activation between Caspase-3−/−, Caspase-3+/− and wild-type mice subjected to H–I, and there was no evidence for compensatory activation of other Caspases in Caspase-3−/− mice. Also, all genotypes showed evidence of mitochondrial dysfunction after H–I, suggesting that this is a critical point in regulation of neuronal cell death following neonatal H–I. Our results suggest that long-term inhibition of Caspase-3 during development, unlike acute inhibition, leads to upregulation of Caspase-3-independent cell death pathways and increases the vulnerability of the developing brain to neonatal H–I injury.
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Role of Caspase-3 in ethanol-induced developmental neurodegeneration.
Neurobiology of disease, 2005Co-Authors: Chainllie Young, Tim West, David M. Holtzman, Kevin A. Roth, Barbara J. Klocke, Joann Labruyere, Yue-qin Qin, Krikor Dikranian, John W. OlneyAbstract:Acute, transient exposure to ethanol causes a widespread pattern of Caspase-3 activation and neuroapoptosis in the developing rodent brain. To determine whether Caspase-3 activation is an essential step in ethanol-induced developmental neuroapoptosis, we treated homozygous Caspase-3 knockout mice or wild-type mice on postnatal day 7 with an apoptosis-inducing dose of ethanol and examined the brains at appropriate survival times for evidence of apoptotic neurodegeneration. In Caspase-3 knockout mice, the cell death process evolved more slowly than in wild-type mice, and morphological changes observed were not those typically associated with apoptosis. However, neuronal cell counts performed 2 weeks post-treatment revealed that the extent of neuron loss was similar in wild-type and Caspase-3-deficient mice. We conclude that absence of functional Caspase-3 alters the time course and morphological characteristics of the neurodegenerative process but does not prevent ethanol-induced neuron death.
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bdnf blocks Caspase 3 activation in neonatal hypoxia ischemia
Neurobiology of Disease, 2000Co-Authors: Byung Hee Han, Anselm Dcosta, Stephen A Back, Maia Parsadanian, Shilen N Patel, Aarti R Shah, Jeffrey M Gidday, Anu Srinivasan, Mohanish Deshmukh, David M. HoltzmanAbstract:Hypoxic-ischemic (H-I) injury to the brain in the perinatal period often leads to significant long-term neurological deficits. In a model of neonatal H-I injury in postnatal day 7 rats, our previous data have shown that cell death with features of apoptosis is prominent between 6 and 24 h after H-I and that neurotrophins, particularly BDNF, can markedly protect against tissue loss. During brain development, Caspase-3 is required for normal levels of programmed cell death. Utilizing an antibody specific for the activated form of Caspase-3, CM1, we now show that Caspase-3 is specifically activated in neuronal cell bodies and their processes beginning at 6 h and peaking 24 h following unilateral carotid ligation and exposure to hypoxia in postnatal day 7 rats. Caspase-3 activation began to occur in cortex at 6 h and in striatum and hippocampus at 12-18 h. Caspase-3 activation was also observed in developing oligodendrocytes. Intracerebroventricular injection of BDNF prior to H-I injury almost completely abolished evidence of H-I-induced Caspase-3 activation in vivo. Utilizing a specific molecular marker of an apoptotic pathway, these findings demonstrate that H-I injury to the developing brain is a strong apoptotic stimulus leading to Caspase-3 activation, that BDNF can block this process in vivo, and that the ability of BDNF to inhibit Caspase activation and subsequent apoptosis likely accounts in large part for its protection against neuronal injury in this model.
Donald W Nicholson - One of the best experts on this subject based on the ideXlab platform.
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correlating the fractional inhibition of Caspase 3 in nt2 cells with apoptotic markers using an active Caspase 3 enzyme linked immunosorbent assay
Analytical Biochemistry, 2006Co-Authors: Paul Tawa, Donald W Nicholson, Andre Giroux, Erich Grimm, Yongxin Han, Steven XanthoudakisAbstract:Abstract A rapid and quantitative method for measuring the activity and fractional inhibition of enzymes within their natural cellular environment remains an unmet need in drug discovery. We describe the use of a nonradioactive quantitative enzyme-linked immunosorbent assay (ELISA) for measuring intracellular Caspase activity that is amenable to robotic automation. The ELISA specifically detects active-Caspase-3 and was used to correlate the in-cell activity of Caspase-3 with the progress of Caspase-3-mediated events under varying concentrations of Caspase-3 inhibitors in NT2 cells. We examined the cleavage of endogenous substrates (poly(ADP-ribose)polymerase and αII-spectrin), the extent of DNA fragmentation, and the autocatalytic removal of the Caspase-3 prodomain as markers of Caspase-3 activity. To impart inhibition of the downstream markers, a greater level of Caspase-3 inhibition was required. Although the functional markers were found not to accurately predict intracellular Caspase-3 activity, we found that the inhibition of intracellular Caspase-3 was highly correlated ( R 2 = 0.96) to the inhibition of DNA fragmentation. Also, by comparing the potency of the different inhibitors against the intracellular enzyme versus the purified enzyme, the effects of inhibitor functional groups on whole-cell activity were addressed.
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Differential regulation of Caspase-3 by pharmacological and developmental stimuli as demonstrated using humanised Caspase-3 mice.
Apoptosis : an international journal on programmed cell death, 2004Co-Authors: Lorraine E. Kerr, Donald W Nicholson, J-l A Birse-archbold, A Simon, N Logan, F Scott, G Carlson, John S. Kelly, J. SharkeyAbstract:Caspase-3 is a potential therapeutic target for a number of degenerative diseases. However the development of specific Caspase-3 inhibitors has been hampered by inter-species differences and the high degree of homology shared by different Caspases. To circumvent these issues, we have produced and characterised a humanised Caspase-3 mouse line (possessing one copy of the human gene with both copies of the murine gene disrupted) by crossing human Caspase-3 transgenic mice with nullizygous Caspase-3 knock-out mice. Humanised mice appeared normal and survived to adulthood. Analysis of the human gene revealed that human pro-Caspase-3 was expressed in the same tissues as its murine counterpart. However humanised mice retained the hypercellularity of frontal cortex seen in their knock-out parental line and there was no biochemical evidence of human protein processing during naturally occurring neuronal death taking place during brain development. In contrast, the human protein was cleaved by the mouse machinery following anti-Fas treatment of adult mice. These data suggest that there is a fundamental difference between the activation pathways leading to Caspase-3 cleavage during naturally occurring cell death in development/embryogenesis and following an apoptotic stimulus in the adult.
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Nicotinyl aspartyl ketones as inhibitors of Caspase-3.
Bioorganic & medicinal chemistry letters, 2003Co-Authors: Elise Isabel, Donald W Nicholson, W Cameron Black, Christopher I Bayly, Erich L Grimm, Marc K Janes, Daniel J Mckay, Dita M Rasper, Johanne Renaud, Sophie RoyAbstract:Caspase-3 is a cysteinyl protease that mediates apoptotic cell death. Its inhibition may have an important impact in the treatment of several degenerative diseases. Since P(1) aspartic acid is a required element of recognition for this enzyme, a library of capped aspartyl aldehydes was synthesized using solid-phase chemistry. The 5-bromonicotinamide derivative of the aspartic acid aldehyde was identified to be an inhibitor of Caspase-3. Substitution at the 5-position of the pyridine ring and conversion of the aldehyde to ketones led to a series of potent inhibitors of Caspase-3.
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Caspase-3 is activated following axotomy of neonatal facial motoneurons and Caspase-3 gene deletion delays axotomy-induced cell death in rodents.
European Journal of Neuroscience, 2000Co-Authors: Jacqueline L. Vanderluit, Lowell T. Mcphail, Christopher B. Mcbride, Karl J.l. Fernandes, Claire Huguenot, Donald W Nicholson, George S. Robertson, Wolfram TetzlaffAbstract:In this report, we examined the possible functions of the cell death protease, Caspase-3, in the axotomy-induced apoptosis of facial motoneurons in newborn rodents. Using in situ hybridization and Western blot, we found higher levels of Caspase-3 mRNA and pro-Caspase-3 protein expression in motoneurons of neonatal and 2-week-old rats than adult rats. Following facial motoneuron axotomy, Caspase-3 mRNA and protein expression increased in motoneurons of both neonatal and adult rats. However, using an antibody directed to the activated form of the Caspase-3 protease, we found that catalytically active Caspase-3 was present only in axotomized neonatal motoneurons. As motoneurons in neonatal but not adult rodents are susceptible to axotomy-induced apoptosis, we hypothesized that Caspase-3 may play a role in their demise. To determine the necessity of Caspase-3 activation in axotomy-induced apoptosis, we counted the number of surviving motoneurons at 4 and 7 days following axotomy in wild type mice and Caspase-3 gene-deleted mice. There were nearly three times more surviving motoneurons in Caspase-3 gene-deleted mice than in wild type mice at both 4 days (mean 1074 vs. 464, P
Katsuhiko Mikoshiba - One of the best experts on this subject based on the ideXlab platform.
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Inositol 1,4,5-Trisphosphate Receptor Type 1 Is a Substrate for Caspase-3 and Is Cleaved during Apoptosis in a Caspase-3-dependent Manner
The Journal of biological chemistry, 1999Co-Authors: Junji Hirota, Teiichi Furuichi, Katsuhiko MikoshibaAbstract:The inositol 1,4,5-trisphosphate (IP(3)) receptor (IP(3)R), an IP(3)-gated Ca(2+) channel located on intracellular Ca(2+) stores, modulates intracellular Ca(2+) signaling. During apoptosis of the human T-cell line, Jurkat cells, as induced by staurosporine or Fas ligation, IP(3)R type 1 (IP(3)R1) was found to be cleaved. IP(3)R1 degradation during apoptosis was inhibited by pretreatment of Jurkat cells with the Caspase-3 (-like protease) inhibitor, Ac-DEVD-CHO, and the Caspases inhibitor, z-VAD-CH(2)DCB but not by the Caspase-1 (-like protease) inhibitor, Ac-YVAD-CHO, suggesting that IP(3)R1 was cleaved by a Caspase-3 (-like) protease. The recombinant Caspase-3 cleaved IP(3)R1 in vitro to produce a fragmentation pattern consistent with that seen in Jurkat cells undergoing apoptosis. N-terminal amino acid sequencing revealed that the major cleavage site is (1888)DEVD*(1892)R (mouse IP(3)R1), which involves consensus sequence for Caspase-3 cleavage (DEVD). To determine whether IP(3)R1 is cleaved by Caspase-3 or is proteolyzed in its absence by other Caspases, we examined the cleavage of IP(3)R1 during apoptosis in the MCF-7 breast carcinoma cell line, which has genetically lost Caspase-3. Tumor necrosis factor-alpha- or staurosporine-induced apoptosis in Caspase-3-deficient MCF-7 cells failed to demonstrate cleavage of IP(3)R1. In contrast, MCF-7/Casp-3 cells stably expressing Caspase-3 showed IP(3)R1 degradation upon apoptotic stimuli. Therefore IP(3)R1 is a newly identified Caspase-3 substrate, and Caspase-3 is essential for the cleavage of IP(3)R1 during apoptosis. This cleavage resulted in a decrease in the channel activity as IP(3)R1 was digested, indicating that Caspase-3 inactivates IP(3)R1 channel functions.
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inositol 1 4 5 trisphosphate receptor type 1 is a substrate for Caspase 3 and is cleaved during apoptosis in a Caspase 3 dependent manner
Journal of Biological Chemistry, 1999Co-Authors: Junji Hirota, Teiichi Furuichi, Katsuhiko MikoshibaAbstract:Next Section Abstract The inositol 1,4,5-trisphosphate (IP3) receptor (IP3R), an IP3-gated Ca2+ channel located on intracellular Ca2+ stores, modulates intracellular Ca2+signaling. During apoptosis of the human T-cell line, Jurkat cells, as induced by staurosporine or Fas ligation, IP3R type 1 (IP3R1) was found to be cleaved. IP3R1 degradation during apoptosis was inhibited by pretreatment of Jurkat cells with the Caspase-3 (-like protease) inhibitor, Ac-DEVD-CHO, and the Caspases inhibitor, z-VAD-CH2DCB but not by the Caspase-1 (-like protease) inhibitor, Ac-YVAD-CHO, suggesting that IP3R1 was cleaved by a Caspase-3 (-like) protease. The recombinant Caspase-3 cleaved IP3R1 in vitro to produce a fragmentation pattern consistent with that seen in Jurkat cells undergoing apoptosis. N-terminal amino acid sequencing revealed that the major cleavage site is 1888DEVD*1892R (mouse IP3R1), which involves consensus sequence for Caspase-3 cleavage (DEVD). To determine whether IP3R1 is cleaved by Caspase-3 or is proteolyzed in its absence by other Caspases, we examined the cleavage of IP3R1 during apoptosis in the MCF-7 breast carcinoma cell line, which has genetically lost Caspase-3. Tumor necrosis factor-α- or staurosporine-induced apoptosis in Caspase-3-deficient MCF-7 cells failed to demonstrate cleavage of IP3R1. In contrast, MCF-7/Casp-3 cells stably expressing Caspase-3 showed IP3R1 degradation upon apoptotic stimuli. Therefore IP3R1 is a newly identified Caspase-3 substrate, and Caspase-3 is essential for the cleavage of IP3R1 during apoptosis. This cleavage resulted in a decrease in the channel activity as IP3R1 was digested, indicating that Caspase-3 inactivates IP3R1 channel functions.
Marcello D'amelio - One of the best experts on this subject based on the ideXlab platform.
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Caspase-3 in the Central Nervous System: Beyond Apoptosis
Trends in neurosciences, 2012Co-Authors: Marcello D'amelio, Morgan Sheng, Francesco CecconiAbstract:Caspase-3 has been identified as a key mediator of neuronal programmed cell death. This protease plays a central role in the developing nervous system and its activation is observed early in neural tube formation and persists during postnatal differentiation of the neural network. Caspase-3 activation, a crucial event of neuronal cell death program, is also a feature of many chronic neurodegenerative diseases. This traditional apoptotic function of Caspase-3 is challenged by recent studies that reveal new cell death-independent roles for mitochondrial-activated Caspase-3 in neurite pruning and synaptic plasticity. These findings underscore the need for further research into the mechanism of action and functions of Caspase-3 that may prove useful in the development of novel pharmacological treatments for a diverse range of neurological disorders.
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Neuronal Caspase-3 signaling: not only cell death
Cell death and differentiation, 2009Co-Authors: Marcello D'amelio, Virve Cavallucci, Francesco CecconiAbstract:Caspases are a family of cysteinyl aspartate-specific proteases that are highly conserved in multicellular organisms and function as central regulators of apoptosis. A member of this family, Caspase-3, has been identified as a key mediator of apoptosis in neuronal cells. Recent studies in snail, fly and rat suggest that Caspase-3 also functions as a regulatory molecule in neurogenesis and synaptic activity. In this study, in addition to providing an overview of the mechanism of Caspase-3 activation, we review genetic and pharmacological studies of apoptotic and nonapoptotic functions of Caspase-3 and discuss the regulatory mechanism of Caspase-3 for executing nonapoptotic functions in the central nervous system. Knowledge of biochemical pathway(s) for nonapoptotic activation and modulation of Caspase-3 has potential implications for the understanding of synaptic failure in the pathophysiology of neurological disorders. Fine-tuning of Caspase-3 lays down a new challenge in identifying pharmacological avenues for treatment of many neurological disorders.