The Experts below are selected from a list of 17934 Experts worldwide ranked by ideXlab platform
Emmanuel Brouillet - One of the best experts on this subject based on the ideXlab platform.
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neuroprotective effect of zvad against the neurotoxin 3 nitropropionic acid involves inhibition of calpain
Neuropharmacology, 2005Co-Authors: Nicolas Bizat, Carine Jacquard, Jeanmichel Hermel, Philippe Hantraye, Mariechristine Galas, Frederic Boyer, Serge N Schiffmann, David Blum, Emmanuel BrouilletAbstract:The contribution of calpains and caspases to cell death has been widely studied using pharmacological inhibitors. Among them, the caspase inhibitor N-benzyloxycarbonyl-valyl-alanyl-aspartyl-fluoromethylketone (zVAD) has been used as a specific caspase inhibitor in nearly 1000 published studies. However, several studies showed that zVAD also behaves as a calpain inhibitor in peripheral cells. The effects of zVAD as a calpain inhibitor have never been assessed in neurodegeneration models. We examined here whether zVAD could reduce neurodegeneration in Huntington's disease models using the mitochondrial inhibitor 3-nitropropionic acid (3NP). In these models, 3NP toxicity has been shown to require calpain activation. In rats, intra-cerebro-ventricular infusion of zVAD significantly reduced 3NP-induced striatal degeneration, and decreased the 3NP-induced activation of calpain and calpain-dependent cleavage of fodrin. zVAD (100 microM) also blocked 3NP-induced death of cultured striatal neurons. In vitro, zVAD inhibited purified mu-calpain with high affinity (IC50=10 nM). The present data demonstrate that zVAD protects neurons against 3NP through calpain inhibition. This suggests that, in certain models of neuronal death where zVAD showed protective effects, caspases but also calpains may be involved.
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in vivo calpain caspase cross talk during 3 nitropropionic acid induced striatal degeneration implication of a calpain mediated cleavage of active caspase 3
Journal of Biological Chemistry, 2003Co-Authors: Nicolas Bizat, Sandrine Humbert, Carine Jacquard, Christophe Creminon, Carole Escartin, Frederic Saudou, Stan Krajewski, Jeanmichel Hermel, Philippe Hantraye, Emmanuel BrouilletAbstract:Abstract The role of caspases and calpains in neurodegeneration remains unclear. In this study, we focused on these proteases in a rat model of Huntington's disease using the mitochondrial toxin 3-nitropropionic acid (3NP). Results showed that 3NP-induced death of striatal neurons was preceded by cytochrome c redistribution, transient caspase-9 processing, and activation of calpain, whereas levels of the active/processed form of caspase-3 remained low and were even reduced as compared with control animals. We evidenced here that this decrease in active caspase-3 levels could be attributed to calpain activation. Several observations supported this conclusion. 1) Pharmacological blockade of calpain in 3NP-treated rats increased the levels of endogenous processed caspase-9 and caspase-3. 2) Cell-free extracts prepared from the striatum of 3NP-treated rats degraded in vitro the p34 and p20 subunits of active recombinant caspase-9 and caspase-3, respectively. 3) This degradation of p34 and p20 could be mimicked by purified μ-calpain and was prevented by calpain inhibitors. 4) μ-Calpain produced a loss of the DEVDase (Asp-Glu-Val-Asp) activity of active caspase-3. 5) Western blot analysis and experiments with 35S-radiolabeled caspase-3 showed that μ-calpain cleaved the p20 subunit of active caspase-3 near its catalytic site. 6) μ-Calpain activity was selectively inhibited (IC50 of 100 μm) by a 12 amino acid peptide corresponding to the C terminus of p20. Our results showed that calpain can down-regulate the caspase-9/caspase-3 cell death pathway during neurodegeneration due to chronic mitochondrial defects in vivo and that this effect may involve, at least in part, direct cleavage of the caspase-3 p20 subunit.
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$In\ Vivo$ Calpain/Caspase Cross-talk during 3-Nitropropionic Acid-induced Striatal Degeneration
Journal of Biological Chemistry, 2003Co-Authors: Nicolas Bizat, Sandrine Humbert, Carine Jacquard, Christophe Creminon, Carole Escartin, Frederic Saudou, Stan Krajewski, Jeanmichel Hermel, Philippe Hantraye, Emmanuel BrouilletAbstract:The role of caspases and calpains in neurodegeneration remains unclear. In this study, we focused on these proteases in a rat model of Huntington's disease using the mitochondrial toxin 3-nitropropionic acid (3NP). Results showed that 3NP-induced death of striatal neurons was preceded by cytochrome c redistribution, transient caspase-9 processing, and activation of calpain, whereas levels of the active/processed form of caspase-3 remained low and were even reduced as compared with control animals. We evidenced here that this decrease in active caspase-3 levels could be attributed to calpain activation. Several observations supported this conclusion. 1) Pharmacological blockade of calpain in 3NP-treated rats increased the levels of endogenous processed caspase-9 and caspase-3. 2) Cell-free extracts prepared from the striatum of 3NP-treated rats degraded $in\ vitro$ the p34 and p20 subunits of active recombinant caspase-9 and caspase-3, respectively. 3) This degradation of p34 and p20 could be mimicked by purified $\mu$-calpain and was prevented by calpain inhibitors. 4) $\mu$-Calpain produced a loss of the DEVDase (Asp-Glu-Val-Asp) activity of active caspase-3. 5) Western blot analysis and experiments with $^{35}$S-radiolabeled caspase-3 showed that $\mu$-calpain cleaved the p20 subunit of active caspase-3 near its catalytic site. 6) $\mu$-Calpain activity was selectively inhibited (IC$_{50}$ of 100 $\mu$M) by a 12 amino acid peptide corresponding to the C terminus of p20. Our results showed that calpain can down-regulate the caspase-9/caspase-3 cell death pathway during neurodegeneration due to chronic mitochondrial defects $in\ vivo$ and that this effect may involve, at least in part, direct cleavage of the caspase-3 p20 subunit.
Athar H. Chishti - One of the best experts on this subject based on the ideXlab platform.
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Calpain-1 ablation partially rescues disease-associated hallmarks in models of Machado-Joseph disease
Human molecular genetics, 2020Co-Authors: Jonasz J. Weber, Athar H. Chishti, Eva Haas, Yacine Maringer, Stefan Hauser, Nicolas Casadei, Olaf Riess, Jeannette Hübener-schmidAbstract:Proteolytic fragmentation of polyglutamine-expanded ataxin-3 is a concomitant and modifier of the molecular pathogenesis of Machado-Joseph disease (MJD), the most common autosomal dominant cerebellar ataxia. Calpains, a group of calcium-dependent cysteine proteases, are important mediators of ataxin-3 cleavage and implicated in multiple neurodegenerative conditions. Pharmacologic and genetic approaches lowering calpain activity showed beneficial effects on molecular and behavioural disease characteristics in MJD model organisms. However, specifically targeting one of the calpain isoforms by genetic means has not yet been evaluated as a potential therapeutic strategy. In our study, we tested whether calpains are overactivated in the MJD context and if reduction or ablation of calpain-1 expression ameliorates the disease-associated phenotype in MJD cells and mice. In all analysed MJD models, we detected an elevated calpain activity at baseline. Lowering or removal of calpain-1 in cells or mice counteracted calpain system overactivation and led to reduced cleavage of ataxin-3 without affecting its aggregation. Moreover, calpain-1 knockout in YAC84Q mice alleviated excessive fragmentation of important synaptic proteins. Despite worsening some motor characteristics, YAC84Q mice showed a rescue of body weight loss and extended survival upon calpain-1 knockout. Together, our findings emphasize the general potential of calpains as a therapeutic target in MJD and other neurodegenerative diseases.
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Calpain-2 Compensation Promotes Angiotensin II-Induced Ascending and Abdominal Aortic Aneurysms in Calpain-1 Deficient Mice
PloS one, 2013Co-Authors: Venkateswaran Subramanian, Athar H. Chishti, Jessica J. Moorleghen, Deborah A. Howatt, Anju Balakrishnan, Haruhito A. UchidaAbstract:Background and Objective Recently, we demonstrated that angiotensin II (AngII)-infusion profoundly increased both aortic protein and activity of calpains, calcium-activated cysteine proteases, in mice. In addition, pharmacological inhibition of calpain attenuated AngII-induced abdominal aortic aneurysm (AA) in mice. Recent studies have shown that AngII infusion into mice leads to aneurysmal formation localized to the ascending aorta. However, the precise functional contribution of calpain isoforms (-1 or -2) in AngII-induced abdominal AA formation is not known. Similarly, a functional role of calpain in AngII-induced ascending AA remains to be defined. Using BDA-410, an inhibitor of calpains, and calpain-1 genetic deficient mice, we examined the relative contribution of calpain isoforms in AngII-induced ascending and abdominal AA development. Methodology/Results To investigate the relative contribution of calpain-1 and -2 in development of AngII-induced AAs, male LDLr −/− mice that were either calpain-1 +/+ or −/− were fed a saturated fat-enriched diet and infused with AngII (1,000 ng/kg/min) for 4 weeks. Calpain-1 deficiency had no significant effect on body weight or blood pressure during AngII infusion. Moreover, calpain-1 deficiency showed no discernible effects on AngII-induced ascending and abdominal AAs. Interestingly, AngII infusion induced increased expression of calpain-2 protein, thus compensating for total calpain activity in aortas of calpain-1 deficient mice. Oral administration of BDA-410, a calpain inhibitor, along with AngII-infusion significantly attenuated AngII-induced ascending and abdominal AA formation in both calpain-1 +/+ and −/− mice as compared to vehicle administered mice. Furthermore, BDA-410 administration attenuated AngII-induced aortic medial hypertrophy and macrophage accumulation. Western blot and immunostaining analyses revealed BDA-410 administration attenuated AngII-induced C-terminal fragmentation of filamin A, an actin binding cytoskeletal protein in aorta. Conclusion Calpain-2 compensates for loss of calpain-1, and both calpain isoforms are involved in AngII-induced aortic aneurysm formation in mice.
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Abstract 516: Calpain-2 Compensation Promotes Angiotensin II-induced Ascending and Abdominal Aortic Aneurysms in Calpain-1 Deficient Mice
Arteriosclerosis Thrombosis and Vascular Biology, 2013Co-Authors: Venkateswaran Subramanian, Athar H. Chishti, Jessica J. Moorleghen, Deborah A. Howatt, Anju Balakrishnan, Haruhito A. UchidaAbstract:Background and Objective We demonstrated that angiotensin II (AngII)-infusion profoundly increased both aortic protein and activity of calpains, calcium-activated cysteine proteases, in mice. In addition, pharmacological inhibition of calpain attenuated AngII-induced abdominal aortic aneurysm (AA) in mice. Recent studies have shown that AngII infusion into mice leads to aneurysmal formation localized to the ascending aorta. However, the precise functional contribution of calpain isoforms (-1 or -2) in AngII-induced abdominal AA formation is not known. Similarly, a functional role of calpain in AngII-induced ascending AA remains to be defined. Using BDA-410, an inhibitor of calpains, and calpain-1 genetic deficient mice, we examined the relative contribution of calpain isoforms in AngII-induced ascending and abdominal AA development. Methods and Results Male LDLr-/- mice that were either calpain-1 +/+ or -/- were fed a saturated fat-enriched diet and infused with AngII (1,000 ng/kg/min) for 4 weeks. Calpain-1 deficiency had no effect on body weight or blood pressure during AngII infusion. Intimal areas of ascending aorta and maximum external width of the suprarenal abdominal aorta were measured by en face. Calpain-1 deficiency showed no discernible effects on AngII-induced ascending and abdominal AA development (P = NS). Interestingly, AngII infusion induced increased expression of calpain-2 protein, thus compensating for total calpain activity in aortas of calpain-1 deficient mice. Oral administration of BDA-410 along with AngII infusion significantly attenuated AngII-induced ascending (Vehicle - +/+: 15.0 ± 1.0, -/-: 14.9 ± 0.8; BDA: +/+: 11.5 ± 0.6, -/-: 12.1 ± 0.6 mm 2 ; P Conclusion Calpain-2 compensates for loss of calpain-1, and promotes AngII-induced ascending and abdominal AAs in calpain-1 deficient mice.
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targeted gene inactivation reveals a functional role of calpain 1 in platelet spreading
Journal of Thrombosis and Haemostasis, 2012Co-Authors: S. M. Kuchay, Adam J. Wieschhaus, Marina Marinkovic, Ira M. Herman, Athar H. ChishtiAbstract:To cite this article: Kuchay SM, Wieschhaus AJ, Marinkovic M, Herman IM, Chishti AH. Targeted gene inactivation reveals a functional role of Calpain-1 in platelet spreading. J Thromb Haemost 2012; 10: 1120–32. Summary. Background: Calpains are implicated in a wide range of cellular functions including the maintenance of hemostasis via the regulation of cytoskeletal modifications in platelets. Objectives: Determine the functional role of calpain isoforms in platelet spreading. Methods and Results: Platelets from calpain-1 )/) mice show enhanced spreading on collagenand fibrinogen-coated surfaces as revealed by immunofluorescence, differential interference contrast (DIC) and scanning electron microscopy. The treatment of mouse platelets with MDL, a cell permeable inhibitor of calpains 1/2, resulted in increased spreading. The PTP1B-mediated enhanced tyrosine dephosphorylation in calpain-1 )/) platelets did not fully account for the enhanced spreading as platelets from the double knockout mice lacking calpain-1 and PTP1B showed only a partial rescue of the spreading phenotype. In nonadherent platelets, proteolysis and GTPase activity of RhoA and Rac1 were indistinguishable between the wild-type (WT) and calpain-1 )/) platelets. In contrast, the ECM-adherent calpain-1 )/) platelets showed higher Rac1 activity at the beginning of spreading, whereas RhoA was more active at later time points. The ECM-adherent calpain-1 )/) platelets showed an elevated level of RhoA protein but not Rac1 and Cdc42. Proteolysis of recombinant RhoA, but not Rac1 and Cdc42, indicates that RhoA is a calpain-1 substrate in vitro. Conclusions: Potentiation of the platelet spreading phenotype in calpain-1 )/) mice suggests a novel role of calpain-1 in hemostasis, and may explain the normal bleeding time observed in the calpain-1 )/) mice.
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Targeted gene inactivation reveals a functional role of calpain‐1 in platelet spreading
Journal of Thrombosis and Haemostasis, 2012Co-Authors: S. M. Kuchay, Adam J. Wieschhaus, Marina Marinkovic, Ira M. Herman, Athar H. ChishtiAbstract:To cite this article: Kuchay SM, Wieschhaus AJ, Marinkovic M, Herman IM, Chishti AH. Targeted gene inactivation reveals a functional role of Calpain-1 in platelet spreading. J Thromb Haemost 2012; 10: 1120–32. Summary. Background: Calpains are implicated in a wide range of cellular functions including the maintenance of hemostasis via the regulation of cytoskeletal modifications in platelets. Objectives: Determine the functional role of calpain isoforms in platelet spreading. Methods and Results: Platelets from calpain-1 )/) mice show enhanced spreading on collagenand fibrinogen-coated surfaces as revealed by immunofluorescence, differential interference contrast (DIC) and scanning electron microscopy. The treatment of mouse platelets with MDL, a cell permeable inhibitor of calpains 1/2, resulted in increased spreading. The PTP1B-mediated enhanced tyrosine dephosphorylation in calpain-1 )/) platelets did not fully account for the enhanced spreading as platelets from the double knockout mice lacking calpain-1 and PTP1B showed only a partial rescue of the spreading phenotype. In nonadherent platelets, proteolysis and GTPase activity of RhoA and Rac1 were indistinguishable between the wild-type (WT) and calpain-1 )/) platelets. In contrast, the ECM-adherent calpain-1 )/) platelets showed higher Rac1 activity at the beginning of spreading, whereas RhoA was more active at later time points. The ECM-adherent calpain-1 )/) platelets showed an elevated level of RhoA protein but not Rac1 and Cdc42. Proteolysis of recombinant RhoA, but not Rac1 and Cdc42, indicates that RhoA is a calpain-1 substrate in vitro. Conclusions: Potentiation of the platelet spreading phenotype in calpain-1 )/) mice suggests a novel role of calpain-1 in hemostasis, and may explain the normal bleeding time observed in the calpain-1 )/) mice.
Nicolas Bizat - One of the best experts on this subject based on the ideXlab platform.
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neuroprotective effect of zvad against the neurotoxin 3 nitropropionic acid involves inhibition of calpain
Neuropharmacology, 2005Co-Authors: Nicolas Bizat, Carine Jacquard, Jeanmichel Hermel, Philippe Hantraye, Mariechristine Galas, Frederic Boyer, Serge N Schiffmann, David Blum, Emmanuel BrouilletAbstract:The contribution of calpains and caspases to cell death has been widely studied using pharmacological inhibitors. Among them, the caspase inhibitor N-benzyloxycarbonyl-valyl-alanyl-aspartyl-fluoromethylketone (zVAD) has been used as a specific caspase inhibitor in nearly 1000 published studies. However, several studies showed that zVAD also behaves as a calpain inhibitor in peripheral cells. The effects of zVAD as a calpain inhibitor have never been assessed in neurodegeneration models. We examined here whether zVAD could reduce neurodegeneration in Huntington's disease models using the mitochondrial inhibitor 3-nitropropionic acid (3NP). In these models, 3NP toxicity has been shown to require calpain activation. In rats, intra-cerebro-ventricular infusion of zVAD significantly reduced 3NP-induced striatal degeneration, and decreased the 3NP-induced activation of calpain and calpain-dependent cleavage of fodrin. zVAD (100 microM) also blocked 3NP-induced death of cultured striatal neurons. In vitro, zVAD inhibited purified mu-calpain with high affinity (IC50=10 nM). The present data demonstrate that zVAD protects neurons against 3NP through calpain inhibition. This suggests that, in certain models of neuronal death where zVAD showed protective effects, caspases but also calpains may be involved.
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in vivo calpain caspase cross talk during 3 nitropropionic acid induced striatal degeneration implication of a calpain mediated cleavage of active caspase 3
Journal of Biological Chemistry, 2003Co-Authors: Nicolas Bizat, Sandrine Humbert, Carine Jacquard, Christophe Creminon, Carole Escartin, Frederic Saudou, Stan Krajewski, Jeanmichel Hermel, Philippe Hantraye, Emmanuel BrouilletAbstract:Abstract The role of caspases and calpains in neurodegeneration remains unclear. In this study, we focused on these proteases in a rat model of Huntington's disease using the mitochondrial toxin 3-nitropropionic acid (3NP). Results showed that 3NP-induced death of striatal neurons was preceded by cytochrome c redistribution, transient caspase-9 processing, and activation of calpain, whereas levels of the active/processed form of caspase-3 remained low and were even reduced as compared with control animals. We evidenced here that this decrease in active caspase-3 levels could be attributed to calpain activation. Several observations supported this conclusion. 1) Pharmacological blockade of calpain in 3NP-treated rats increased the levels of endogenous processed caspase-9 and caspase-3. 2) Cell-free extracts prepared from the striatum of 3NP-treated rats degraded in vitro the p34 and p20 subunits of active recombinant caspase-9 and caspase-3, respectively. 3) This degradation of p34 and p20 could be mimicked by purified μ-calpain and was prevented by calpain inhibitors. 4) μ-Calpain produced a loss of the DEVDase (Asp-Glu-Val-Asp) activity of active caspase-3. 5) Western blot analysis and experiments with 35S-radiolabeled caspase-3 showed that μ-calpain cleaved the p20 subunit of active caspase-3 near its catalytic site. 6) μ-Calpain activity was selectively inhibited (IC50 of 100 μm) by a 12 amino acid peptide corresponding to the C terminus of p20. Our results showed that calpain can down-regulate the caspase-9/caspase-3 cell death pathway during neurodegeneration due to chronic mitochondrial defects in vivo and that this effect may involve, at least in part, direct cleavage of the caspase-3 p20 subunit.
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$In\ Vivo$ Calpain/Caspase Cross-talk during 3-Nitropropionic Acid-induced Striatal Degeneration
Journal of Biological Chemistry, 2003Co-Authors: Nicolas Bizat, Sandrine Humbert, Carine Jacquard, Christophe Creminon, Carole Escartin, Frederic Saudou, Stan Krajewski, Jeanmichel Hermel, Philippe Hantraye, Emmanuel BrouilletAbstract:The role of caspases and calpains in neurodegeneration remains unclear. In this study, we focused on these proteases in a rat model of Huntington's disease using the mitochondrial toxin 3-nitropropionic acid (3NP). Results showed that 3NP-induced death of striatal neurons was preceded by cytochrome c redistribution, transient caspase-9 processing, and activation of calpain, whereas levels of the active/processed form of caspase-3 remained low and were even reduced as compared with control animals. We evidenced here that this decrease in active caspase-3 levels could be attributed to calpain activation. Several observations supported this conclusion. 1) Pharmacological blockade of calpain in 3NP-treated rats increased the levels of endogenous processed caspase-9 and caspase-3. 2) Cell-free extracts prepared from the striatum of 3NP-treated rats degraded $in\ vitro$ the p34 and p20 subunits of active recombinant caspase-9 and caspase-3, respectively. 3) This degradation of p34 and p20 could be mimicked by purified $\mu$-calpain and was prevented by calpain inhibitors. 4) $\mu$-Calpain produced a loss of the DEVDase (Asp-Glu-Val-Asp) activity of active caspase-3. 5) Western blot analysis and experiments with $^{35}$S-radiolabeled caspase-3 showed that $\mu$-calpain cleaved the p20 subunit of active caspase-3 near its catalytic site. 6) $\mu$-Calpain activity was selectively inhibited (IC$_{50}$ of 100 $\mu$M) by a 12 amino acid peptide corresponding to the C terminus of p20. Our results showed that calpain can down-regulate the caspase-9/caspase-3 cell death pathway during neurodegeneration due to chronic mitochondrial defects $in\ vivo$ and that this effect may involve, at least in part, direct cleavage of the caspase-3 p20 subunit.
Haruhito A. Uchida - One of the best experts on this subject based on the ideXlab platform.
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Calpain-2 Compensation Promotes Angiotensin II-Induced Ascending and Abdominal Aortic Aneurysms in Calpain-1 Deficient Mice
PloS one, 2013Co-Authors: Venkateswaran Subramanian, Athar H. Chishti, Jessica J. Moorleghen, Deborah A. Howatt, Anju Balakrishnan, Haruhito A. UchidaAbstract:Background and Objective Recently, we demonstrated that angiotensin II (AngII)-infusion profoundly increased both aortic protein and activity of calpains, calcium-activated cysteine proteases, in mice. In addition, pharmacological inhibition of calpain attenuated AngII-induced abdominal aortic aneurysm (AA) in mice. Recent studies have shown that AngII infusion into mice leads to aneurysmal formation localized to the ascending aorta. However, the precise functional contribution of calpain isoforms (-1 or -2) in AngII-induced abdominal AA formation is not known. Similarly, a functional role of calpain in AngII-induced ascending AA remains to be defined. Using BDA-410, an inhibitor of calpains, and calpain-1 genetic deficient mice, we examined the relative contribution of calpain isoforms in AngII-induced ascending and abdominal AA development. Methodology/Results To investigate the relative contribution of calpain-1 and -2 in development of AngII-induced AAs, male LDLr −/− mice that were either calpain-1 +/+ or −/− were fed a saturated fat-enriched diet and infused with AngII (1,000 ng/kg/min) for 4 weeks. Calpain-1 deficiency had no significant effect on body weight or blood pressure during AngII infusion. Moreover, calpain-1 deficiency showed no discernible effects on AngII-induced ascending and abdominal AAs. Interestingly, AngII infusion induced increased expression of calpain-2 protein, thus compensating for total calpain activity in aortas of calpain-1 deficient mice. Oral administration of BDA-410, a calpain inhibitor, along with AngII-infusion significantly attenuated AngII-induced ascending and abdominal AA formation in both calpain-1 +/+ and −/− mice as compared to vehicle administered mice. Furthermore, BDA-410 administration attenuated AngII-induced aortic medial hypertrophy and macrophage accumulation. Western blot and immunostaining analyses revealed BDA-410 administration attenuated AngII-induced C-terminal fragmentation of filamin A, an actin binding cytoskeletal protein in aorta. Conclusion Calpain-2 compensates for loss of calpain-1, and both calpain isoforms are involved in AngII-induced aortic aneurysm formation in mice.
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Abstract 516: Calpain-2 Compensation Promotes Angiotensin II-induced Ascending and Abdominal Aortic Aneurysms in Calpain-1 Deficient Mice
Arteriosclerosis Thrombosis and Vascular Biology, 2013Co-Authors: Venkateswaran Subramanian, Athar H. Chishti, Jessica J. Moorleghen, Deborah A. Howatt, Anju Balakrishnan, Haruhito A. UchidaAbstract:Background and Objective We demonstrated that angiotensin II (AngII)-infusion profoundly increased both aortic protein and activity of calpains, calcium-activated cysteine proteases, in mice. In addition, pharmacological inhibition of calpain attenuated AngII-induced abdominal aortic aneurysm (AA) in mice. Recent studies have shown that AngII infusion into mice leads to aneurysmal formation localized to the ascending aorta. However, the precise functional contribution of calpain isoforms (-1 or -2) in AngII-induced abdominal AA formation is not known. Similarly, a functional role of calpain in AngII-induced ascending AA remains to be defined. Using BDA-410, an inhibitor of calpains, and calpain-1 genetic deficient mice, we examined the relative contribution of calpain isoforms in AngII-induced ascending and abdominal AA development. Methods and Results Male LDLr-/- mice that were either calpain-1 +/+ or -/- were fed a saturated fat-enriched diet and infused with AngII (1,000 ng/kg/min) for 4 weeks. Calpain-1 deficiency had no effect on body weight or blood pressure during AngII infusion. Intimal areas of ascending aorta and maximum external width of the suprarenal abdominal aorta were measured by en face. Calpain-1 deficiency showed no discernible effects on AngII-induced ascending and abdominal AA development (P = NS). Interestingly, AngII infusion induced increased expression of calpain-2 protein, thus compensating for total calpain activity in aortas of calpain-1 deficient mice. Oral administration of BDA-410 along with AngII infusion significantly attenuated AngII-induced ascending (Vehicle - +/+: 15.0 ± 1.0, -/-: 14.9 ± 0.8; BDA: +/+: 11.5 ± 0.6, -/-: 12.1 ± 0.6 mm 2 ; P Conclusion Calpain-2 compensates for loss of calpain-1, and promotes AngII-induced ascending and abdominal AAs in calpain-1 deficient mice.
Carine Jacquard - One of the best experts on this subject based on the ideXlab platform.
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neuroprotective effect of zvad against the neurotoxin 3 nitropropionic acid involves inhibition of calpain
Neuropharmacology, 2005Co-Authors: Nicolas Bizat, Carine Jacquard, Jeanmichel Hermel, Philippe Hantraye, Mariechristine Galas, Frederic Boyer, Serge N Schiffmann, David Blum, Emmanuel BrouilletAbstract:The contribution of calpains and caspases to cell death has been widely studied using pharmacological inhibitors. Among them, the caspase inhibitor N-benzyloxycarbonyl-valyl-alanyl-aspartyl-fluoromethylketone (zVAD) has been used as a specific caspase inhibitor in nearly 1000 published studies. However, several studies showed that zVAD also behaves as a calpain inhibitor in peripheral cells. The effects of zVAD as a calpain inhibitor have never been assessed in neurodegeneration models. We examined here whether zVAD could reduce neurodegeneration in Huntington's disease models using the mitochondrial inhibitor 3-nitropropionic acid (3NP). In these models, 3NP toxicity has been shown to require calpain activation. In rats, intra-cerebro-ventricular infusion of zVAD significantly reduced 3NP-induced striatal degeneration, and decreased the 3NP-induced activation of calpain and calpain-dependent cleavage of fodrin. zVAD (100 microM) also blocked 3NP-induced death of cultured striatal neurons. In vitro, zVAD inhibited purified mu-calpain with high affinity (IC50=10 nM). The present data demonstrate that zVAD protects neurons against 3NP through calpain inhibition. This suggests that, in certain models of neuronal death where zVAD showed protective effects, caspases but also calpains may be involved.
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in vivo calpain caspase cross talk during 3 nitropropionic acid induced striatal degeneration implication of a calpain mediated cleavage of active caspase 3
Journal of Biological Chemistry, 2003Co-Authors: Nicolas Bizat, Sandrine Humbert, Carine Jacquard, Christophe Creminon, Carole Escartin, Frederic Saudou, Stan Krajewski, Jeanmichel Hermel, Philippe Hantraye, Emmanuel BrouilletAbstract:Abstract The role of caspases and calpains in neurodegeneration remains unclear. In this study, we focused on these proteases in a rat model of Huntington's disease using the mitochondrial toxin 3-nitropropionic acid (3NP). Results showed that 3NP-induced death of striatal neurons was preceded by cytochrome c redistribution, transient caspase-9 processing, and activation of calpain, whereas levels of the active/processed form of caspase-3 remained low and were even reduced as compared with control animals. We evidenced here that this decrease in active caspase-3 levels could be attributed to calpain activation. Several observations supported this conclusion. 1) Pharmacological blockade of calpain in 3NP-treated rats increased the levels of endogenous processed caspase-9 and caspase-3. 2) Cell-free extracts prepared from the striatum of 3NP-treated rats degraded in vitro the p34 and p20 subunits of active recombinant caspase-9 and caspase-3, respectively. 3) This degradation of p34 and p20 could be mimicked by purified μ-calpain and was prevented by calpain inhibitors. 4) μ-Calpain produced a loss of the DEVDase (Asp-Glu-Val-Asp) activity of active caspase-3. 5) Western blot analysis and experiments with 35S-radiolabeled caspase-3 showed that μ-calpain cleaved the p20 subunit of active caspase-3 near its catalytic site. 6) μ-Calpain activity was selectively inhibited (IC50 of 100 μm) by a 12 amino acid peptide corresponding to the C terminus of p20. Our results showed that calpain can down-regulate the caspase-9/caspase-3 cell death pathway during neurodegeneration due to chronic mitochondrial defects in vivo and that this effect may involve, at least in part, direct cleavage of the caspase-3 p20 subunit.
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$In\ Vivo$ Calpain/Caspase Cross-talk during 3-Nitropropionic Acid-induced Striatal Degeneration
Journal of Biological Chemistry, 2003Co-Authors: Nicolas Bizat, Sandrine Humbert, Carine Jacquard, Christophe Creminon, Carole Escartin, Frederic Saudou, Stan Krajewski, Jeanmichel Hermel, Philippe Hantraye, Emmanuel BrouilletAbstract:The role of caspases and calpains in neurodegeneration remains unclear. In this study, we focused on these proteases in a rat model of Huntington's disease using the mitochondrial toxin 3-nitropropionic acid (3NP). Results showed that 3NP-induced death of striatal neurons was preceded by cytochrome c redistribution, transient caspase-9 processing, and activation of calpain, whereas levels of the active/processed form of caspase-3 remained low and were even reduced as compared with control animals. We evidenced here that this decrease in active caspase-3 levels could be attributed to calpain activation. Several observations supported this conclusion. 1) Pharmacological blockade of calpain in 3NP-treated rats increased the levels of endogenous processed caspase-9 and caspase-3. 2) Cell-free extracts prepared from the striatum of 3NP-treated rats degraded $in\ vitro$ the p34 and p20 subunits of active recombinant caspase-9 and caspase-3, respectively. 3) This degradation of p34 and p20 could be mimicked by purified $\mu$-calpain and was prevented by calpain inhibitors. 4) $\mu$-Calpain produced a loss of the DEVDase (Asp-Glu-Val-Asp) activity of active caspase-3. 5) Western blot analysis and experiments with $^{35}$S-radiolabeled caspase-3 showed that $\mu$-calpain cleaved the p20 subunit of active caspase-3 near its catalytic site. 6) $\mu$-Calpain activity was selectively inhibited (IC$_{50}$ of 100 $\mu$M) by a 12 amino acid peptide corresponding to the C terminus of p20. Our results showed that calpain can down-regulate the caspase-9/caspase-3 cell death pathway during neurodegeneration due to chronic mitochondrial defects $in\ vivo$ and that this effect may involve, at least in part, direct cleavage of the caspase-3 p20 subunit.
