Academic literature on the topic 'Calpain 1'

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Journal articles on the topic "Calpain 1"

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Upla, Paula, Varpu Marjomäki, Liisa Nissinen, Camilla Nylund, Matti Waris, Timo Hyypiä, and Jyrki Heino. "Calpain 1 and 2 Are Required for RNA Replication of Echovirus 1." Journal of Virology 82, no. 3 (November 21, 2007): 1581–90. http://dx.doi.org/10.1128/jvi.01375-07.

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ABSTRACT Calpains are calcium-dependent cysteine proteases that degrade cytoskeletal and cytoplasmic proteins. We have studied the role of calpains in the life cycle of human echovirus 1 (EV1). The calpain inhibitors, including calpeptin, calpain inhibitor 1, and calpain inhibitor 2 as well as calpain 1 and calpain 2 short interfering RNAs, completely blocked EV1 infection in the host cells. The effect of the inhibitors was not specific for EV1, because they also inhibited infection by other picornaviruses, namely, human parechovirus 1 and coxsackievirus B3. The importance of the calpains in EV1 infection also was supported by the fact that EV1 increased calpain activity 3 h postinfection. Confocal microscopy and immunoelectron microscopy showed that the EV1/caveolin-1-positive vesicles also contain calpain 1 and 2. Our results indicate that calpains are not required for virus entry but that they are important at a later stage of infection. Calpain inhibitors blocked the production of EV1 particles after microinjection of EV1 RNA into the cells, and they effectively inhibited the synthesis of viral RNA in the host cells. Thus, both calpain 1 and calpain 2 are essential for the replication of EV1 RNA.
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Weber, Jonasz J., Eva Haas, Yacine Maringer, Stefan Hauser, Nicolas L. P. Casadei, Athar H. Chishti, Olaf Riess, and Jeannette Hübener-Schmid. "Calpain-1 ablation partially rescues disease-associated hallmarks in models of Machado-Joseph disease." Human Molecular Genetics 29, no. 6 (January 21, 2020): 892–906. http://dx.doi.org/10.1093/hmg/ddaa010.

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Abstract 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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Ben-Aharon, Irit, Paula R. Brown, Nir Etkovitz, Edward M. Eddy, and Ruth Shalgi. "The expression of calpain 1 and calpain 2 in spermatogenic cells and spermatozoa of the mouse." Reproduction 129, no. 4 (April 2005): 435–42. http://dx.doi.org/10.1530/rep.1.00255.

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There is some evidence suggesting that Ca2+is involved in processes that occur during the development and function of spermatozoa. Calcium-dependent proteins, such as calmodulin, are expressed during mammalian spermatogenesis further suggesting that Ca2+takes part in its regulation. However, the precise roles of Ca2+in spermatogenesis remain to be elucidated. Calpains are a family of Ca2+-dependent cysteine proteases whose members are expressed ubiquitously or in a tissue-specific manner. Calpain has been demonstrated to mediate specific Ca2+-dependent processes including cell fusion, mitosis and meiosis. We herein followed the expression pattern of calpain’s ubiquitous isoforms, 1 and 2, throughout spermatogenesis at the RNA and protein levels by RT-PCR and Western blotting analysis. Both RNA and protein studies revealed that these isoforms are expressed in all spermatogenic cells. The expression of calpain 1 levels is slightly higher in spermatocytes entering the meiotic phase. Both calpain isoforms are also expressed in mouse spermatozoa and are localized to the acrosomal cap. Inducing capacitated spermatozoa to undergo the acrosome reaction in the presence of a selective calpain inhibitor significantly reduced the acrosome reaction rate in a dose-dependent manner. Thus, calpain, a pluripotential protease with numerous substrates, may serve as an effector in more than one pathway in the complex process of spermatogenesis and in the events preceding fertilization, such as the acrosome reaction.
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Baudry, Michel. "Calpain-1 and Calpain-2 in the Brain: Dr. Jekill and Mr Hyde?" Current Neuropharmacology 17, no. 9 (August 22, 2019): 823–29. http://dx.doi.org/10.2174/1570159x17666190228112451.

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While the calpain system has now been discovered for over 50 years, there is still a paucity of information regarding the organization and functions of the signaling pathways regulated by these proteases, although calpains play critical roles in many cell functions. Moreover, calpain overactivation has been shown to be involved in numerous diseases. Among the 15 calpain isoforms identified, calpain-1 (aka µ-calpain) and calpain-2 (aka m-calpain) are ubiquitously distributed in most tissues and organs, including the brain. We have recently proposed that calpain-1 and calpain- 2 play opposite functions in the brain, with calpain-1 activation being required for triggering synaptic plasticity and neuroprotection (Dr. Jekill), and calpain-2 limiting the extent of plasticity and being neurodegenerative (Mr. Hyde). Calpain-mediated cleavage has been observed in cytoskeleton proteins, membrane-associated proteins, receptors/channels, scaffolding/anchoring proteins, and protein kinases and phosphatases. This review will focus on the signaling pathways related to local protein synthesis, cytoskeleton regulation and neuronal survival/death regulated by calpain-1 and calpain-2, in an attempt to explain the origin of the opposite functions of these 2 calpain isoforms. This will be followed by a discussion of the potential therapeutic applications of selective regulators of these 2 calpain isoforms.
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Murphy, Robyn M., Rodney J. Snow, and Graham D. Lamb. "μ-Calpain and calpain-3 are not autolyzed with exhaustive exercise in humans." American Journal of Physiology-Cell Physiology 290, no. 1 (January 2006): C116—C122. http://dx.doi.org/10.1152/ajpcell.00291.2005.

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μ-calpain and calpain-3 are Ca2+-dependent proteases found in skeletal muscle. Autolysis of calpains is observed using Western blot analysis as the cleaving of the full-length proteins to shorter products. Biochemical assays suggest that μ-calpain becomes proteolytically active in the presence of 2–200 μM Ca2+. Although calpain-3 is poorly understood, autolysis is thought to result in its activation, which is widely thought to occur at lower intracellular Ca2+ concentration levels ([Ca2+]i; ∼1 μM) than the levels at which μ-calpain activation occurs. We have demonstrated the Ca2+-dependent autolysis of the calpains in human muscle samples and rat extensor digitorum longus (EDL) muscles homogenized in solutions mimicking the intracellular environment at various [Ca2+] levels (0, 2.5, 10, and 25 μM). Autolysis of calpain-3 was found to occur across a [Ca2+] range similar to that for μ-calpain, and both calpains displayed a seemingly higher Ca2+ sensitivity in human than in rat muscle homogenates, with ∼15% autolysis observed after 1-min exposure to 2.5 μM Ca2+ in human muscle and almost none after 1- to 2-min exposure to the same [Ca2+]i level in rat muscle. During muscle activity, [Ca2+]i may transiently peak in the range found to autolyze μ-calpain and calpain-3, so we examined the effect of two types of exhaustive cycling exercise (30-s “all-out” cycling, n = 8; and 70% V̇o2 peak until fatigue, n = 3) on the amount of autolyzed μ-calpain or calpain-3 in human muscle. No significant autolysis of μ-calpain or calpain-3 occurred as a result of the exercise. These findings have shown that the time- and concentration-dependent changes in [Ca2+]i that occurred during concentric exercise fall near but below the level necessary to cause autolysis of calpains in vivo.
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McCartney, Christian-Scott E., Qilu Ye, Robert L. Campbell, and Peter L. Davies. "Insertion sequence 1 from calpain-3 is functional in calpain-2 as an internal propeptide." Journal of Biological Chemistry 293, no. 46 (September 25, 2018): 17716–30. http://dx.doi.org/10.1074/jbc.ra118.004803.

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Calpains are intracellular, calcium-activated cysteine proteases. Calpain-3 is abundant in skeletal muscle, where its mutation-induced loss of function causes limb-girdle muscular dystrophy type 2A. Unlike the small subunit–containing calpain-1 and -2, the calpain-3 isoform homodimerizes through pairing of its C-terminal penta-EF-hand domain. It also has two unique insertion sequences (ISs) not found in the other calpains: IS1 within calpain-3's protease core and IS2 just prior to the penta-EF-hand domain. Production of either native or recombinant full-length calpain-3 to characterize the function of these ISs is challenging. Therefore, here we used recombinant rat calpain-2 as a stable surrogate and inserted IS1 into its equivalent position in the protease core. As it does in calpain-3, IS1 occupied the catalytic cleft and restricted the enzyme's access to substrate and inhibitors. Following activation by Ca2+, IS1 was rapidly cleaved by intramolecular autolysis, permitting the enzyme to freely accept substrate and inhibitors. The surrogate remained functional until extensive intermolecular autoproteolysis inactivated the enzyme, as is typical of calpain-2. Although the small-molecule inhibitors E-64 and leupeptin limited intermolecular autolysis of the surrogate, they did not block the initial intramolecular cleavage of IS1, establishing its role as a propeptide. Surprisingly, the large-molecule calpain inhibitor, calpastatin, completely blocked enzyme activity, even with IS1 intact. We suggest that calpastatin is large enough to oust IS1 from the catalytic cleft and take its place. We propose an explanation for why calpastatin can inhibit calpain-2 bearing the IS1 insertion but cannot inhibit WT calpain-3.
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Covington, Marisa D., David D. Arrington, and Rick G. Schnellmann. "Calpain 10 is required for cell viability and is decreased in the aging kidney." American Journal of Physiology-Renal Physiology 296, no. 3 (March 2009): F478—F486. http://dx.doi.org/10.1152/ajprenal.90477.2008.

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Aging is associated with abnormalities in kidney function, but the exact mechanisms are unknown. We examined calpains 1, 2, and 10 protein levels in kidneys from rats, mice, and humans of various ages and determined whether calpain 10 is required for cell viability. Calpain 10 protein expression decreased in the kidney, but not in the liver, of aging Fischer 344 rats, and this decrease was attenuated with caloric restriction. There was no change in calpains 1 or 2 levels in the kidney or liver in control and caloric-restricted aging rats. Aging mice also exhibited decreased calpain 10 protein levels. Calpain 10 protein and mRNA levels decreased linearly in human kidney samples with age in the absence of changes in calpains 1 or 2. Our laboratory previously found calpain 10 to be expressed in both the cytosol and mitochondria of rabbit renal proximal tubular cells (RPTC). Adenoviral-delivered shRNA to rabbit RPTC decreased mitochondrial calpain 10 expression below detectable levels by 3 days while cytosolic calpain 10 levels remained unchanged at 3 days and decreased to ∼20% of control by 5 days. Knockdown of mitochondrial calpain 10 resulted in nuclear condensation and cleaved procaspase 3, markers of apoptosis. In summary, mitochondrial calpain 10 is required for cell viability and calpain 10 levels specifically decrease in aging rat, mice, and human kidney tissues when renal function decreases, suggesting that calpain 10 is required for renal function and is a biomarker of the aging kidney.
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Piper, Ann-Katrin, Reece A. Sophocleous, Samuel E. Ross, Frances J. Evesson, Omar Saleh, Adam Bournazos, Joe Yasa, et al. "Loss of calpains-1 and -2 prevents repair of plasma membrane scrape injuries, but not small pores, and induces a severe muscular dystrophy." American Journal of Physiology-Cell Physiology 318, no. 6 (June 1, 2020): C1226—C1237. http://dx.doi.org/10.1152/ajpcell.00408.2019.

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The ubiquitous calpains, calpain-1 and -2, play important roles in Ca2+-dependent membrane repair. Mechanically active tissues like skeletal muscle are particularly reliant on mechanisms to repair and remodel membrane injury, such as those caused by eccentric damage. We demonstrate that calpain-1 and -2 are master effectors of Ca2+-dependent repair of mechanical plasma membrane scrape injuries, although they are dispensable for repair/removal of small wounds caused by pore-forming agents. Using CRISPR gene-edited human embryonic kidney 293 (HEK293) cell lines, we established that loss of both calpains-1 and -2 ( CAPNS1−/−) virtually ablates Ca2+-dependent repair of mechanical scrape injuries but does not affect injury or recovery from perforation by streptolysin-O or saponin. In contrast, cells with targeted knockout of either calpain-1 ( CAPN1−/−) or -2 ( CAPN2−/−) show near-normal repair of mechanical injuries, inferring that both calpain-1 and calpain-2 are equally capable of conducting the cascade of proteolytic cleavage events to reseal a membrane injury, including that of the known membrane repair agent dysferlin. A severe muscular dystrophy in a murine model with skeletal muscle knockout of Capns1 highlights vital roles for calpain-1 and/or -2 for health and viability of skeletal muscles not compensated for by calpain-3 ( CAPN3). We propose that the dystrophic phenotype relates to loss of maintenance of plasma membrane/cytoskeletal networks by calpains-1 and -2 in response to directed and dysfunctional Ca2+-signaling, pathways hyperstimulated in the context of membrane injury. With CAPN1 variants associated with spastic paraplegia, a severe dystrophy observed with muscle-specific loss of calpain-1 and -2 activity identifies CAPN2 and CAPNS1 as plausible candidate neuromuscular disease genes.
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Pánico, Pablo, Marcia Hiriart, Patricia Ostrosky-Wegman, and Ana María Salazar. "TUG is a calpain-10 substrate involved in the translocation of GLUT4 in adipocytes." Journal of Molecular Endocrinology 65, no. 3 (October 2020): 45–57. http://dx.doi.org/10.1530/jme-19-0253.

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The calpain-10 (CAPN10) protease is implicated in the translocation of the glucose transporter 4 (GLUT4), which is retained in the Golgi matrix via the Tether containing a UBX domain for GLUT4 (TUG) protein. Insulin stimulation induces the proteolytic processing of TUG, which leads to the translocation of GLUT4 to the cell membrane. We tested whether TUG is a CAPN10 substrate. Proteolysis of TUG by calpains was assessed using a cell-free system containing calpain-1 and TUG. In situ proteolysis of TUG by calpains was demonstrated in 3T3-L1 adipocytes in the presence of insulin or calpain inhibitors to modulate calpain activity. Proteolysis of TUG by CAPN10 was confirmed using transient or stable silencing of CAPN10 in 3T3-L1 adipocytes. Calpains proteolyzed the C-terminus of TUG in vitro. In adipocytes, insulin-induced cleavage of TUG was correlated with the activation of calpains. Treatment with calpain inhibitors reduced TUG cleavage, resulting in impaired GLUT4 translocation without altering Akt phosphorylation. Furthermore, CAPN10 but not calpain-1 or calpain-2 colocalized with GLUT4 in the absence of insulin, and their colocalization was reduced after stimulation with insulin. Finally, we demonstrated that CAPN10 knockdown reduced the proteolysis of TUG without altering the phosphorylation of Akt or the expression of the Usp25m protease. Thus, our results provide evidence that the TUG protein is cleaved by CAPN10 to regulate GLUT4 translocation.
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Ou, B. R., and N. E. Forsberg. "Determination of skeletal muscle calpain and calpastatin activities during maturation." American Journal of Physiology-Endocrinology and Metabolism 261, no. 6 (December 1, 1991): E677—E683. http://dx.doi.org/10.1152/ajpendo.1991.261.6.e677.

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Our objectives were to characterize events underlying changes in skeletal muscle calpain and calpastatin activities, using maturation as a model. Muscle samples were taken from rabbits of four ages (newborn and 1, 2, and 5 mo old). Concentrations of RNA and protein and activities of calpains I and II and calpastatin were determined. Steady-state concentrations of mRNAs encoding calpain I, calpain II, calpastatin, alpha- and beta-tubulin, and beta-actin were determined using Northern blot analysis. Calpain and calpastatin activities declined markedly between birth and 1 mo of age and remained unchanged thereafter. Several factors accounted for the neonatal losses of calpains and calpastatin. First, muscle protein concentration increased between birth and 1 mo of age and diluted calpain and calpastatin specific activities. Second, there was a marked reduction of muscle RNA concentration between birth and 1 mo of age, which indicates that protein synthetic capacity declined with age. Finally, calpastatin mRNA concentration declined between birth and 1 mo of age and further contributed to developmental losses of calpastatin activity. Calpain I mRNA concentration was unaffected by age, and although calpain II mRNA concentration declined with age, losses were not detected between birth and 1 mo; hence age-related changes in calpain I and II activities are not mediated at the mRNA level. The age-related reductions in calpain II and calpastatin mRNA concentrations resembled age-related changes in alpha- and beta-tubulin and beta-actin mRNA concentration.(ABSTRACT TRUNCATED AT 250 WORDS)
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Dissertations / Theses on the topic "Calpain 1"

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Ishak, Reezal. "Calpain-1 : investigating its role in murine neutrophils." Thesis, Cardiff University, 2012. http://orca.cf.ac.uk/37448/.

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Neutrophils are phagocytic white blood cells which act as the first line of defence against entry of foreign microorganisms. Neutrophils are recruited to their target site through the process of spreading, extravasation and phagocytosis involving complex signal transduction within the cells, which might include the activation of the cytosolic Ca2+ activated protease, calpain-1. The work described here investigates the role of calpain-1 in regulating neutrophil functions such as spreading, trans-endothelial migration, chemotaxis, phagocytosis and Ca2+ signalling. Through the work done at European Mutant Mouse Archive (EMMA), Oxford, and by using intracellular sperm injection (ICSI) of calpain-1 deleted gene from mice generated in the USA, and with a selective genotype breeding programme, a colony of homozygous calpain-1 KO mouse has been generated in Cardiff. Homozygous calpain-1 KO neutrophils appeared to have a smaller surface spreading area and their recruitment into the peritoneal cavity of the mouse in vivo was disrupted. In vitro experiments showed significant defects in their ability to cross the ICAM-1 expressing endothelial cells in trans-endothelial migration assay. Disruption in this transmigration was only evident with ICAM-1 upregulated (TNF-treated) endothelial cells, suggesting a specific defect in the β2 integrin-ICAM-1 signalling process. Calpain-1 absence did not affect signal transduction as neutrophils were able to signal cytosolic Ca2+ in response to β2 integrin engagement (C3bi-opsonised zymosan) and also to release intracellular Ca2+ store upon IP3 uncaging. This showed that the IP3 pathway in the cells was not affected by knocking-out calpain-1 and continued to be functional. The key signalling mechanisms from β2 integrin also remained intact and this is consistent with calpain-1 activation by Ca2+ being an important event in trans-endothelial migration. In conclusion, calpain-1 absence has significantly affected the ability of neutrophils to undergo trans-endothelial migration and this effect is directed towards the event which happens downstream to the increase in cytosolic free Ca2+ concentration.
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Hanouna, Guillaume. "Rôle des calpaïnes dans le vieillissement et la réponse anti-tumorale." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066385/document.

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Les calpaïnes 1 et 2 sont des protéases à cystéine ubiquitaires et la calpastatine est leur inhibiteur naturel, également ubiquitaire. Les calpaïnes sont impliquées dans le développement de la réponse inflammatoire via l’activation par protéolyse partielle de plusieurs substrats (activation de NF-κB par le clivage de I-κBα, remodelage du cytosquelette des cellules inflammatoires, clivage de la protéine chaperonne HSP 90…).Il a été précédemment démontré que les calpaïnes favorisent le vieillissement neuronal. Nous avons pu montrer dans un modèle murin que l’inhibition in vivo des calpaïnes par la surexpression de calpastatine limite le vieillissement notamment rénal et vasculaire. L’inflammation liée au vieillissement ou « inflammaging » est considérablement réduite par l’inhibition spécifique des calpaïnes. Ceci est dû, au moins en partie, à l’effet des calpaïnes sur la production de cytokines pro-inflammatoires et sur la maturation de l’interleukine-1.Si les calpaïnes intracellulaires exercent un rôle pro-inflammatoire, les calpaïnes externalisées ont un effet anti-inflammatoire via le clivage de TLR2. Les calpaïnes peuvent en effet être excrétées hors des cellules via les transporteurs ABCA1. Dans le cadre d’un modèle murin de mélanome, nous avons pu montrer que l’inhibition des seules calpaïnes extracellulaires par la surexpression de calpastatine extracellulaire préserve TLR2 et limite ainsi la progression de la tumeur.Les calpaïnes intra- et extracellulaires sont des médiateurs majeurs de la réponse inflammatoire et modulent « l’inflammaging » ainsi que la réponse immune anti-tumorale
Calpain 1 and 2 are cysteine proteases and calpastatin is their natural inhibitor. Calpains and calpastatin are ubiquitous. Calpains are involved in inflammatory response development via activation by partial proteolysis of several substrates (NF-kappaB activation by I-kappaBalpha cleavage, remodeling of inflammatory cells cytoskeleton, cleavage of chaperone protein HSP90 ... ). It has been previously shown that calpains promote neuronal aging. We have shown in a mouse model that inhibition of calpain by calpastatin overexpression limits renal and vascular aging. The inflammation associated with aging or "inflammaging" is considerably reduced by specific inhibition of calpain. This is due, at least in part, to calpain effect on production of pro-inflammatory cytokines and in maturation of interleukin-1 alpha. If intracellular calpains are pro-inflammatory, secreted calpains have an anti-inflammatory effect via cleavage of TLR2. Calpains can indeed be excreted out of the cells via the transporter ABCA1. In the context of a mouse model of melanoma, we have shown that inhibition of extracellular calpain by only extracellular calpastatin overexpression preserves TLR2 and thus limit the progression of the tumor.Calpains intra- and extracellular are major mediators of inflammatory response and modulate the "inflammaging" and the anti-tumor immune response
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Mendes, Atlante Silva. "Verapamil diminui a expressão proteica de calpaína-1 e metaloproteinase de matriz-2 na hipertrofia cardíaca induzida por hipertensão renovascular." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/17/17133/tde-08112018-150232/.

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Introdução: A hipertrofia cardíaca induzida por sobrecarga hemodinâmica crônica (HC) é caracterizada por espessamento das paredes do ventrículo esquerdo e do tecido intersticial. As atividades aumentadas de calpaína-1 e metaloproteinase de matriz(MMP)-2 são observadas em diferentes modelos de hipertensão arterial e estão relacionadas com as mudanças fisiopatológicas na HC. Por outro lado, a atividade de MMP-2 parece ser modulada positivamente por ativação de calpaína-1 em diferentes modelos. O objetivo deste trabalho é analizar se a calpaína-1 contribui para o aumento da atividade de MMP-2 no coração e se esse mecanismo resulta nas mudanças crônicas cardíacas na hipertensão renovascular. Métodos: Ratos Wistar submetidos ao modelo de 2-rins-1 clipe (2R-1C)(180-200g) e seus respectivos controles (Sham) foram tratados com verapamil (VRP), um bloqueador de canais para cálcio tipo L (BCCL, 8mg/kg/bid) ou veículo durante 8 semanas. O BCCL reduz as concentrações intracelulares de cálcio, o que leva à diminuição da ativação de calpaína-1, e então à possível modulação da atividade e expressão proteica de MMP-2. Pressão arterial sistólica (PAS) dos ratos foi monitorada durante 10 semanas de hipertensão por pletismografia de cauda. O ventrículo esquerdo (VE) foi analisado por histologia e ecocardiografia para avaliação das dimensões ventriculares. A atividade de calpaína-1 e MMP-2 foi avaliada por zimografia em gel. A expessão proteica de calpaína-1 e MMP-2 foi avaliada por western blot e imunofluorescência. Os corações foram submetidos à avaliação funcional por Langendorff. Todos os protocolos foram aprovados pelo Comitê de Ética em Pesquisa Animal da Faculdade de Medicina de Ribeirão Preto (43/2017). Resultados: Após 10 semanas, a PAS teve um aumento sustentado nos animais 2R-1C e o tratamento com VRP não foi capaz de reduzí-la em nenhum tempo de hipertensão. O peso corporal não apresentou diferença significativa entre os grupos. O grupo hipertenso teve um aumento da massa cardíaca quando comparado ao sham e o tratamento com verapamil reduziu esse parâmetro. A análise da espessura do ventrículo esquerdo demonstra que o VRP é capaz de reverter a HC induzida por sobrecarga pressórica nos animais hipertensos. Os animais 2R-1C apresentaram um aumento singificativo na expressão proteica e atividade de calpaína-1 e o VRP foi capaz de diminuir esses níveis. Foi observado aumento da atividade das isoformas de MMP-2 nos ratos 2R-1C quando comparados aos controles e o VRP foi capaz de reduzir a atividade da isoforma de 64kDa. A contratilidade cardíaca intrínseca dos animais 2R-1C sugere uma disfunção cardíaca quando comparados aos controles sham, embora a fração de ejeção desses animais esteja preservada. O VRP não foi capaz de alterar esses parâmetros. Conclusão: O VRP pode contribuir para a redução da hipertrofia cardíaca por diminuir a expressão proteica de calpaína-1 e MMP-2 na hipertensão renovascular. Apoio financeiro: Capes, CNPq, FAPESP
Introduction: The chronic hemodynamic overload-induced cardiac hypertrophy (CH) is characterized by thickening of the left ventricle walls and hypertrophy of the cardiomyocytes and interstitial tissue. Increased activity of calpain-1 and matrix metalloproteinase(MMP)-2 was observed in different models of arterial hypertension models and contributes to the pathophysiologic changes shown in CH. On the other hand, MMP-2 activity is also positively modulated by activation of calpain-1 in different animal models of cardiovascular diseases. The objectives here are to analyze whether calpain-1 contributes to increase the activity of MMP-2 in the heart and whether this mechanism results in chronic cardiac changes in the renovascular hypertension. Methods: Two kidney-one clip (2K1C) hypertensive male Wistar rats (180-200g) and their respective controls (Sham) were orally treated with verapamil (VRP), a L-type calcium channels blocker (LCCB, 8mg/kg/bid), or vehicle during 8 weeks. The LCCB reduces the intracellular concentration of calcium, thus decreasing the activation of calpain-1, and then may modulate the activity of MMP-2. Systolic blood pressure (SBP) was monitored in the rats during 10 weeks of hypertension. Left ventricle (LV) was analyzed by histology and echocardiography to evaluate ventricle thickening. Calpain- 1 and MMP-2 activities were analyzed by zymography and their expression by immunofluorescence and western blot. Hearts were submitted to functional evaluation by Langendorff. All the protocols were approved by the Ethical Committee in Animal Research of Ribeirao Preto Medical School (43/2017). Results: After 10 weeks, the systolic blood pressure had sustained increase and treatment with VRP was not able to decrease it in any time of hypertension. The body weight did not present significant changes between the groups. Hypertensive group had significant increase in the ventricle/body weight ratio (VW/BW) when compared to sham and treatment with VRP decreased it. Analysis of ventricle thickening showed that VRP is able to revert CHinduced pressure overload. The 2K-1C rats showed a significant increase in the activity and expression of calpain-1 in the heart and VRP reverted it. It was also observed increased activity of MMP-2 forms in the hypertensive rats and VRP decreased the 64kDa MMP-2 activity. The 2K-1C group had cardiac dysfunction when compared to controls groups, and VRP did not alter it. The ejection fraction was not changed in 2K- 1C rats. Conclusion: VRP decreased expression and activity of calpain-1 and MMP-2 in the hearts of 2K-1C rats and then contributed to ameliorate hypertension-induced cardiac hypertrophy
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Marion, Allison. "La calpaïne - 6 : une nouvelle cible thérapeutique dans les ostéosarcomes." Paris 7, 2011. http://www.theses.fr/2011PA077134.

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Les ostéosarcomes sont des tumeurs fortement résistantes à la chimiothérapie, qui récidivent et métastasent de façon fréquente. L'objectif de ce travail est d'identifier de nouveaux mécanismes régulant la réponse aux agents cytotoxiques. Précédemment, nous avons mis en évidence le rôle du syndécan-2 dans le contrôle de l'apoptose et la réponse aux agents cytotoxiques des cellules d'ostéosarcome. Ici, nous nous sommes intéressés à la calpaïne-6, l'un des gènes modulés par le syndécan-2. Nous avons montré que le syndécan-2 diminue l'expression de la calpaïne-6 en inhibant les voies de signalisation impliquant PI3K, ERK1/2 et NF-KB induites par l'endothéline-1. Nous avons également mis en évidence une expression anormale de la calpaïne-6 dans les ostéosarcomes. Nous avons établit une corrélation inverse entre l'expression de la calpaïne-6 dans les ostéosarcomes et la réponse aux traitements. Nous avons également observé une forte expression de la calpaïne-6 dans les tumeurs récidivantes. De plus, nous avons montré que l'inhibition de la calpaïne-6 résulte en une augmentation de l'apoptose induite par la chimiothérapie. Ces résultats indiquent que la calpaïne-6 est un facteur protecteur des cellules d'ostéosarcome. Par ailleurs, nous avons montré que le RANKL et Phypoxie coopèrent pour augmenter l'expression de la calpaïne-6 dans les cellules d'ostéosarcome et dans des cellules pouvant donner des métastases osseuses. Nos résultats ont donc permis d'identifier la calpaïne-6 comme un nouvel acteur de la résistance à la chimiothérapie dans les cellules tumorales osseuses. Elle pourrait représenter une nouvelle cible thérapeutique pour améliorer la réponse aux chimiothérapies
Osteosarcomas are chemoresistant tumours that frequently relapse and metastasize. The aim of this study is to identify new mechanisms involved in the regulation of cellular response to cytotoxic agents. We previously showed that syndecan-2 controls apoptosis and cell response to cytotoxic agent in ostosarcomas. To identify new factors involved in osteosarcoma cell survival, we examined genes modified upon syndecan-2 overexpression using a microarray analysis. We found that calpain-6 is one of the genes significantly down-regulated by syndecan-2. We have demonstrated that syndecan-2 modulates Endothelin-1 dependent signalling to reduce calpain-6 expression including PI3K, ERK1/2 and NF-KB signaling pathways. We have also showed that calpain-6 is abnormally expressed in osteosarcoma compared to osteoblastic cell Unes and in tumours. Moreover, we have established an inverse relationship between calpain-6 expression and response to chemotherapy. We have observed a strong calpain-6 expression in recurrent tumours and in resistant cells to doxorubicin. We have showed that calpain-6 inhibition with shRNA increases apoptosis induced by chemotherapy. We identified calpain-6 as a protective factor in osteosarcoma cells. We also showed that RANKL and hypoxia cooperate to induce calpain-6 expression in osteosarcoma cells but also in cancer cells that could metastasize to the bone like breast and prostate cancer cells. Our results led us to identify calpain-6 as a new factor implicated in résistance to chemotherapy in bone cancer cells. Calpain-6 appears to be modulated by the microenvironment. It could be a new therapeutic target to improve response to chemotherapeutic agents
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Peltier, Julie. "Implication du TGF-BETA1 et des calpaïnes dans la glomérulopathie induite par les anticorps anti-membrane basale glomérulaire." Paris 7, 2006. http://www.theses.fr/2006PA077129.

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La réaction inflammatoire au cours des glomérulonéphrites est régulée par de nombreux médiateurs. Parmi eux, le transforming growth factor-beta1 (TGF-β1) peut jouer un rôle anti-inflammatoire, tandis que les calpaïnes, cystéines proteases activées par le calcium, favorisent la réaction inflammatoire. Nous montrons d'abord que le TGF-β1 augmente la synthèse du récepteur des glucocorticoïdes, par le biais des protéines Srnad 2/3 et AP-1. Et qu'il contribue à l'inhibition de la réaction macrophagique. Ensuite, nous montrons que l'activité calpaïne est augmentée dans le cortex rénal au cours des glomérulonéphrites aiguës, et que des calpaïnes actives apparaissent dans les urines. Ces calpaïnes, principalement d'oriqine plasmatique sont la conséquence de l'altération de la membrane basale glomérulaire mais proviennent aussi d'une sécrétion tubulaire. Les calpaïnes activées dans le cortex rénal favorisent le développement des lésions glomérulaires inflammatoires en activant NF-KB. Les calpaïnes urinaires contribuent à l'apparition de la protéinurie en clivant la néphrine, et majorent ainsi probablement l'inflammation péri-tubulaire
Inflammatory process in qlomerulonephritis is regulated by many mediators. Of them, transforming qrowth factor-beta1 (TGF-β1) may act as an anti-inflammatory agent. In contrary, calpain, a calcium-activated neutral cysteine protease, participates in the development of inflammation. We first demonstrate that TGF-β1 increase glucocorticoid receptor (GR) synthesis by macrophages after activation of Smad 2/3 and AP-1. And increase the ability of GR to deactivate macrophages. Second, we show that in glomerulonephritis, calpain activity is increased in the kidney cortex, and that in parallel. Active calpains appear in the urines. These calpains oriqinate mainly from abnormal transglomerular passage of plasma proteins and from tubular secretion. Active calpains in the renal cortex promote glomerular injury through activation of NF-KB. While urinary calpains are responsible for the shedding of nephrin from the surface of podocytes. Thereby worsening proteinura
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Stroop, Davis M. "The Epidemiology of Early Type 2 Diabetes Mellitus in Black and White Females: Genetic and Environmental Factors." University of Cincinnati / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1377870493.

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Muir, Matthew Stewart. "Proteomics of the ovine cataract." Diss., Lincoln University, 2008. http://hdl.handle.net/10182/792.

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The lens of the eye needs to be completely transparent in order to allow all light entering the eye to reach the retina. This transparency is maintained by the highly ordered structure of the lens proteins the crystallins. Any disruption to the lens proteins can cause an opacity to develop which is known as cataract. During cortical cataract formation there is increased truncation of the lens crystallins. It is believed that overactivation of calcium-dependent cysteine proteases, the calpains, is responsible for the increased proteolysis of the crystallins seen during cataractogenesis. Within the ovine lens there are three calpains, calpain 1, 2 and the lens specific calpain Lp82. The aim of this thesis was to determine the changes in the lens proteins during ageing and cataractogenesis, and to establish the role of the calpains in these processes. Calpain 1 and 2 were purified from ovine lung and Lp82 was purified from lamb lenses using chromatography. Activity and presence of the calpains was determined by using the BODIPY-FL casein assay, gel electrophoresis, Western blot and casein zymography. Changes in the lens proteins, specifically the crystallins, were visualised using two-dimensional electrophoresis (2DE). Lenses from fetal, 6 month old and 8 year old sheep were collected, as well as stage 0, 1, 3 and 6 cataractous ovine lenses. The proteins from the lenses were separated into the water soluble and urea soluble fractions and analysed by 2DE. Mass spectrometry was used to determine the masses and therefore modifications of the crystallins. Finally, the individual crystallins were separated using gel filtration chromatography and incubated with the purified calpains in the presence of calcium. The extent of the proteolysis was visualised using 2DE and truncation sites determined by mass spectrometry. Purification of the calpains resulted in samples that were specific for each calpain and could be used in further experiments. 2DE analysis showed that there were changes to the crystallins during maturation of the lens. The α-crystallins become increasingly phosphorylated as the lens ages and a small amount becomes truncated. The β-crystallins were also modified during ageing by truncation and deamidation. When crystallins from cataractous lenses were compared using 2DE there were changes to both the α- and β-crystallins. The α-crystallins were found to be extensively truncated at their C-terminal tail. Four of the seven β-crystallins, βB1, βB3, βB2 and βA3, showed increased truncation of their N-terminal extensions during cataract formation. All three calpains truncated αA and αB-crystallin at their C-terminal ends after incubation. Calpain 2 and Lp82 each produced unique αA-crystallin truncations. All three calpains truncated βB1 and βA3 and calpain 2 also truncated βB3. When the truncations from the calpain incubations were compared to those seen during cataract formation, many of the truncations were found to be similar. Both the unique truncations from calpain 2 and Lp82 were found in cataractous lenses, with the Lp82 more obvious in the 2DE. The β-crystallin truncations found after incubation with the calpains were similar to those found during cataractogenesis. In conclusion this study documents the changes to the ovine lens during maturation and cataractogenesis and indicates a role for the calpain family in the increased proteolysis observed in the ovine cataract.
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Kriegel, Christian. "Untersuchungen zur kapazitationsassoziierten Signaltransduktion in humanen Spermatozoen und Evaluation des MACS-Verfahrens zur Ejakulataufbereitung." Doctoral thesis, Universitätsbibliothek Leipzig, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-114339.

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Als Kapazitation bezeichnet man den im weiblichen Reproduktionstrakt stattfindenden Reifungsschritt, der Spermien das volle Fertilisierungspotential verleiht. Die molekularbiologischen Grundlagen dieses für eine erfolgreiche natürliche oder auch artifizielle Befruchtung essenziellen Prozesses sind bis heute nur unvollständig verstanden. Im Rahmen der vorliegenden Dissertation wurden die mit der Kapazitation einhergehenden funktionellen und strukturellen spermalen Veränderungen untersucht. Die kapazitative Stimulation führte zu einer gesteigerten Motilität bis hin zur Hyperaktivierung, zu einer vermehrt induzierten Akrosomenreaktion und zu einer deutlich reduzierten Apoptoseaktivität. Anhand von Inhibitionsexperimenten wurde die Rolle der potentiellen Signaltransduktoren Caspase-1, Calpain und Calmodulin analysiert. Dabei wies die Calmodulinantagonisierung auf eine ausgeprägte Calciumabhängigkeit aller untersuchten kapazitationsassoziierten Prozesse hin. Die Hemmung von Caspase-1 und Calpain führte zu einer Beeinträchtigung der Motilität und der Akrosomenreaktion ohne das Ausmaß der Apoptoseinduktion zu beeinflussen. Die vorstehend genannten Erkenntnisse wurden zur Evaluation verschiedener Ejakulataufbereitungsprotokolle genutzt. Dabei konnte gezeigt werden, dass die Kombination des modernen Verfahrens der immunomagnetische Zellseparation mit der etablierten Methode der Dichtegradientenzentrifugation dem einfachen Standard in Bezug auf die Anreicherung hochmotiler Spermien mit minimaler Apoptoseaktivität aus frischen wie auch aus kryokonservierten Ejakulaten deutlich überlegen war. Bedeutsam im Hinblick auf eine mögliche pratische Anwendung der immunomagnetischen Zellseparation erscheint der Befund, dass die durch das kombinierte Anreicherungsverfahren erhaltene Spermatozoensubpopulation im Hamsteroozytenpenetrationstest ein signifikant höheres Fertilisierungspotential zeigte.
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Moubarak, Rana. "Caractérisation de la voie de mort cellulaire programmée induite par le dommage à l'ADN : rôles de PARP-1, calpaine, Bax et AIF." Paris 6, 2007. http://www.theses.fr/2007PA066045.

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Le dommage à l’ADN induit une mort cellulaire programmée de type nécrotique à travers les poly(ADP-ribose) polymerases (PARP) et Apoptosis-Inducing Factor (AIF). Suite à l’activation de PARP, AIF est relargué de la mitochondrie et transloque au noyau où il cause la condensation de la chromatine et la fragmentation de l’ADN. Nous avons identifié deux liens moléculaires entre PARP et AIF: les calpaines et Bax. Le dommage à l’ADN induit une mort indépendante de p53 mais impliquant PARP-1 et pas PARP-2. La nécrose due à la sortie d’AIF de la mitochondrie est dépendante des calpaines, mais pas des cathepsines ni des caspases. L’invalidation génétique de Bax, un membre pro-apoptotique de la famille Bcl-2, mais pas de Bak, inhibe à la fois la sortie d’AIF et la mort induite par le dommage à l’ADN. Finalement, nous avons établi l’ordre moléculaire d’activation de PARP-1, les calpaines, Bax puis AIF, et nous démontrons que la sous-expression d’AIF confère une résistance à la nécrose induite par le dommage à l’ADN. Ces études contribuent à l’élucidation des mécanismes régulant la nécrose dépendante d’AIF et impliquent que la nécrose est, comme l’apoptose, une forme de mort cellulaire programmée.
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Fromberg, Iris [Verfasser]. "Immunhistochemische Untersuchungen zur Expression von Calpain 1, Calpain 2 und Calpastatin in Endometrium- und Ovarialkarzinom / vorgelegt von Iris Fromberg." 2009. http://d-nb.info/1006602755/34.

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Books on the topic "Calpain 1"

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Messer, Jeannette S., ed. Calpain. New York, NY: Springer New York, 2019. http://dx.doi.org/10.1007/978-1-4939-8988-1.

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Book chapters on the topic "Calpain 1"

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van Roy, Frans, Volker Nimmrich, Anton Bespalov, Achim Möller, Hiromitsu Hara, Jacob P. Turowec, Nicole A. St. Denis, et al. "Calpain." In Encyclopedia of Signaling Molecules, 225–28. New York, NY: Springer New York, 2012. http://dx.doi.org/10.1007/978-1-4419-0461-4_23.

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Carragher, Neil O. "Assaying Calpain Activity." In Adhesion Protein Protocols, 109–19. Totowa, NJ: Humana Press, 2007. http://dx.doi.org/10.1007/978-1-59745-353-0_9.

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Biswas, Ashim Kumar, and Samarth Tandon. "Casein Zymography for Analysis of Calpain-1 and Calpain-2 Activity." In Methods in Molecular Biology, 31–38. New York, NY: Springer New York, 2019. http://dx.doi.org/10.1007/978-1-4939-8988-1_3.

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Nguyen, Anh T. H., Matthew Campbell, Paul F. Kenna, Anna-Sophia Kiang, Lawrence Tam, Marian M. Humphries, and Peter Humphries. "Calpain and Photoreceptor Apoptosis." In Retinal Degenerative Diseases, 547–52. Boston, MA: Springer US, 2011. http://dx.doi.org/10.1007/978-1-4614-0631-0_69.

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Biswas, Ashim Kumar, and Samarth Tandon. "Single-Step Purification of Calpain-1, Calpain-2, and Calpastatin Using Anion-Exchange Chromatography." In Methods in Molecular Biology, 3–11. New York, NY: Springer New York, 2019. http://dx.doi.org/10.1007/978-1-4939-8988-1_1.

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Wang, Kevin K. W. "Calpain Zymography: General Methodology and Protocol." In Zymography, 279–85. New York, NY: Springer New York, 2017. http://dx.doi.org/10.1007/978-1-4939-7111-4_26.

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del Carmen Lafita-Navarro, Maria, and Maralice Conacci-Sorrell. "Identification of Calpain-Activated Protein Functions." In Methods in Molecular Biology, 149–60. New York, NY: Springer New York, 2019. http://dx.doi.org/10.1007/978-1-4939-8988-1_12.

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Samanta, Krishna, Pulak Kar, Tapati Chakraborti, and Sajal Chakraborti. "An Overview of Endoplasmic Reticulum Calpain System." In Proteases in Health and Disease, 3–19. New York, NY: Springer New York, 2013. http://dx.doi.org/10.1007/978-1-4614-9233-7_1.

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duVerle, David A., and Hiroshi Mamitsuka. "CalCleaveMKL: a Tool for Calpain Cleavage Prediction." In Methods in Molecular Biology, 121–47. New York, NY: Springer New York, 2019. http://dx.doi.org/10.1007/978-1-4939-8988-1_11.

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Kitagawa, Seiichi. "Experimental Manipulation of Calpain Activity In Vitro." In Methods in Molecular Biology, 209–18. New York, NY: Springer New York, 2019. http://dx.doi.org/10.1007/978-1-4939-8988-1_16.

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Conference papers on the topic "Calpain 1"

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Colman, Robert W., Harlan Bradford, and Anjanayaki Annamalai. "FACTOR V IS ACTIVATED AND CLEAVED BY PLATELET CALPAIN: COMPARISON WITH THROMBIN PROTEOLYSIS." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643884.

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Platelets are known to process human and bovine factor V during secretion and/or membrane binding. We therefore studied the functional and structural changes produced in human factor V and Va by purified platelet calpain. A maximum increase in factor V coagulant activity of 2.5-fold over control incubations was observed for calpain (0.6 u/ml) at 25°C in comparison with a 10-fold increment for a thrombin (1 u/ml). Thrombin addition to reactions initiated by calpain resulted in further activation comparable to that of thrombin alone, while subsequent addition of calpain had no effect on the extent or pattern of the activation of factor V by thrombin. The cleavage pattern of factor V produced by these two enzymes are distinctly different. Calpain yields initial components of 210 kDa and 160 kDa within 1 min. Further digestion of the 210 kDa species give rise to polypeptides of 150, 140 and 120 kDa by 2 min with and increase in coagulant activity. The degradation of the 160 kDa polypeptide gives rise to smaller fragments of 130, 100, 90, and 87 kDa. Immunob lot ting of these fragments with the monoclonal antibody B10 directed to factor V and the thrombin generated Cl fragments yields results demonstrating an immunological relationship to the calpain generated components of 210, 160, 140 and 120 kDa. Thus platelet calpain generates a complex cleavage pattern different from thrombin which may explain the partial activation observed.
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verhallen, P. F. J., E. M. Bevers, P. Comfurius, W. M. A. Linkskens, and R. F. A. Zwaal. "CALPAIN-MEDIATED CYTOSKELETAL DEGRADATION CORRELATES WITH STIMULATION OF PLATELET PROCOAGULANT ACTIVITY." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1642821.

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We have shown earlier that the negatively charged phospholipid phosphatidylserine (PS), which becomes translocated from the inner surface to the outer surface of the plasma membrane upon platelet activation, is responsible for platelet procoagulant activity. Studies with erythrocytes have suggested a role for cytoskeletal proteins in the regulation of transmembrane asymmetry of PS. The possibility that platelet cytoskeletal proteins are involved in the loss of transmembrane asymmetry of PS, was explored by correlative investigations of both platelet prooagulant activity and activity of calpain, an endogenous Ca 2+ -dependent thiol-protease, known to hydrolyze major cytoskeletal proteins (e.g.: filamin, talin, myosin). Platelet procoagulant activity was assayed by determination of the prothrombinase activity under conditions at which the catalytic PS-surface was rate-limiting. Calpain-activity was monitored by the appearance of known degradation products of major cytoskeletal proteins. The following results were obtained: (1) The ability of thrombin, collagen, collagen & thrombin, or the Ca -ionophore A23187 to stimulate platelet procoagulant activity closely correlated with their ability to stimulate platelet calpain-activity (2). Generation of platelet procoagulant activity upon platelet stimulation by collagen & thrombin or by A23187 exhibited a time course identical to the development of calpain-activity. In addition, the local anesthetics dibucaine and tetracaine, shown to gradually stimulate calpain activity, were able to generate platelet procoagulant activity with a similar time course. (3) Using a Ca2+ buffering system and A23187 to equilibrate intracellular- and extracellular free Ca2+ , it was found that the Ca2+ -response relationship of both platelet calpain- and pro-coagulant-activity was identical. From these findings we conclude that the degradation of cytoskeletal proteins destroys their putative interactions with PS, enabling this lipid to participate in transbilayer movement, leading to the formation of a procoagulant outer surface of the platelet.
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Oh, Eunhye, Daeil Sung, Youngkwan Cho, Ji Young Kim, Nahyun Lee, Yoon-Jae Kim, Tae-Min Cho, and Jae Hong Seo. "Abstract 5463: Disulfiram suppresses metastasis via induction of anoikis and calpain activation in triple-negative breast cancer." In Proceedings: AACR Annual Meeting 2017; April 1-5, 2017; Washington, DC. American Association for Cancer Research, 2017. http://dx.doi.org/10.1158/1538-7445.am2017-5463.

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Okita, J. R., M. M. Frojmovic, S. Kristopeit, T. Wong, and T. J. Kunicki. "MONTREAL PLATELET SYNDROME: DECREASED ACTIVITY OF PLATELET CALPAINS ASSOCIATED WITH AGGREGATION ABNORMALITIES." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1642822.

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The Montreal platelet syndrome (MPS) is an inherited disorder of platelet function characterized by a) severe thrombocytopenia, b) formation of "giant" platelets upon physical or biochemical stimulation, c) spontaneous aggregation (stir-induced microaggregate formation) and d) a lack of aggregation in response to thrombin. The Bernard-Soulier syndrome (BSS) is similar to MPS in that both syndromes are characterized by "giant" platelets and an abnormal aggregation response to thrombin. BSS patients have a deficiency of specific platelet glycoproteins (GPs). From our investigations we conclude MPS patients have apparently normal amounts of major platelet GPs. However, a defect in calpains (calcium-activated neutral proteinases) was detected in MPS platelets. The specific activity of calpains was decreased by 70% (p<0.001) in the cytosolic fraction of platelets from MPS patients as compared to that of platelets from normal control donors. The calpain activity of platelets from BSS patients was within the normal range.During the course of the biochemical studies, platelets from the MPS patients were shown to exhibit concurrent functional defects, i.e., stir-induced spontaneous aggregation and reduced to absent aggregation response to thrombin. It is concluded that MPS can be distinguished from BSS at the molecular level as follows: 1) MPS platelets contain normal amounts of GPs Ib, V and IX which are decreased or absent in BSS platelets; 2) The specific activity of calpains is reduced in MPS platelets but normal in BSS platelets. Supported by NIH (HL-33925, HL-32279), Amer. Heart Assoc. (85—GA—67, 83-186), Canadian Med. Res. Council (248-59) and Quebec Heart Fndn.
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Choo, Y., T. Sakai, R. Ikebe, A. Jeffers, S. Idell, T. A. Tucker, and M. Ikebe. "Calponin 1 Promotes Myofibroblast Differentiation of Human Pleural Mesothelial Cells During Mesothelial Mesenchymal Transition." In American Thoracic Society 2021 International Conference, May 14-19, 2021 - San Diego, CA. American Thoracic Society, 2021. http://dx.doi.org/10.1164/ajrccm-conference.2021.203.1_meetingabstracts.a4420.

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Berndt, M. "STRUCTURE AND FUNCTION OF THE GLYCOPROTEIN Ib-IX COMPLEX." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643729.

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At high shear flow, the adhesion of platelets to the exposed vascular subendothelium requires von Willebrand factor (vWF) and is dependent upon a specific platelet membrane adhesion receptor, the human platelet membrane glycoprotein (GP) Ib-IX complex. Recent evidence suggests that vWFbinding to the GP Ib-IX complex plays an important role in other key aspects of hemostasis and thrombosis such as shear-induced platelet aggregation and the interaction of platelets with fibrin.Studies in our laboratory with a seriesof murine monoclonal antibodies directed against epitopes on GP lb, GP IX, or against complex-specificepitopes indicate that GP lb and GP IX exist in the intact platelet membrane as a native heterodimer complex(-25,000 copies/platelet). By analysis onSDS-polyacrylamide gels, GP lb has an apparent molecular weight of 170,000 and cnsists of two disulfide-linked subunits, GP Iba (Mr = 135,000) and GP Ibβ (Mr = 25,000),whilst GP IX has an equivalent molecularweight under both nonreducing and reducing conditions (Mr = 22,000).The ±-chain ofGP lb has a central macroglycopeptide core (Mr =90,000) which is highly glycosylated. At each end of themacroglycopeptide region is a domainsensitive to proteolytic cleavage. Cleavage at the end proximal to the platelet membrane, e.g. by calpain, Serratia marcescens metalloprotease and trypsin, generates two fragments :a Mr =130,000 highly glycosylated fragment termed glycocalicin anda membrane-associated region consisting ofa Mr -25,000 fragment that remains disulfide-linkedto GP Ibβ and associated with GP IX. In resting platelets, the membrane-associated region spans the lipid bilayer linking the GP Ib-IX complex to the platelet endoskeleton via actin-binding protein. This membrane-associated region also contains the domain(s) recognized by quinine/quinidine drug-dependent antibodies. Cleavage at the plasma end of the macroglycopeptide, e.g. by human leukocyte elastase, generates a poorly glycosylated Mr = 45,000 fragment of GP Ibα (peptide tail region) and a heavily glycosylated Mr = 100,000 fragment that remains disulfide-linked to GP Ibg and associated with GP IX. Platelets lacking the N-terminal peptide tail region of GP Iba fail to agglutinate with ristocetin and vWF and show a delayed response to a-thrombin.Polyclonal and monoclonal antibodies against this region also inhibit both these platelet responses suggesting that the peptide tail region contains the binding sites for both α-thrombinand vWF. Rotary shadowingelectron microscopy of purified GP Ib-IX complex shows the structure to be highlyasymmetric with each complex existing asa flexible rod with a globular domain at each end. The overall length of the complexwas =60 nm.The smaller globular domain (peptidetail region) has a diameter of =9nm; the larger globular domain (membrane-associated region), a diameter of =16 nmWe have recently examined whetherthe human platelet GP Ib-IX complex is the receptor for the ristocetin-dependent binding of vWF by reconstitution with the purified components using a solid-phasebead assay. Our approach was to indirectlybind and orientate the GP Ib-IX complex onthe beads via a monoclonal antibody directed against the membrane-associated region of the complex (FMC 25, epitope on GP IX).Immunobeads were chosen as the insoluble matrix because they are uniform in size (=10μm in diameter), impermeable,specifically designed for the coupling of IgG, and because, like platelets, the beads have a net negative charge atneutral pH.Specific binding of 125I-labelled human vWF tothe GP Ib-IX complex-coated immunobeads was strictly ristocetin-dependent with maximal binding occurring atristocetin concentrations >1 mg/ml. Ristocetin-dependent specificbinding of 125I-labelled vWF was saturable.Scatchardanalysis revealed a single classof binding sites for vWF with purified GP Ib-IX complex.Monoclonal antibodies against the Mr = 45,000 peptide tail region ofGP lb which stronglyinhibitthe ristocetin-dependent binding ofvWF toplatelets also strongly inhibited the ristocetin-dependent binding of vWFto the GP Ib-IX coated beads. Monoclonalantibody against either themacroglycopeptide or membrane-associated regions of the GPIb-IX complex did not inhibit the ristocetin-dependent binding of vWF to platelets or to the GP Ib-IX complex-coated beads. Similar functional correlations were obtained with anti-vWFmonoclonal antibodies. The reconstitutiondata therefore confirm the functional roleof the GP Ib-IX complex as a major plateletvWF receptor. The region ofthe vWF molecule involved in binding to the GP Ib-IX complex has been localized toa Mr =50,000 domain towards theN-terminal end of the vWF subunit. The reconstitution assay should prove useful in the further definition of active peptides of vWF that bind tothe human platelet GP Ib-IX complex.
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Driscoll, Tristan P., Su-Jin Heo, and Robert L. Mauck. "Dynamic Tensile Loading and Altered Cell Contractility Modulate Nuclear Deformation and Cytoskeletal Connectivity." In ASME 2012 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/sbc2012-80550.

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Effective use of progenitor cells in orthopaedic tissue engineering will require a thorough understanding of the mechanisms by which forces are transmitted and sensed, and how these change with differentiation. Nesprins are a family of structural proteins that partially localize to the nuclear envelope where they interact with both cytoskeletal and nucleoskeletal proteins [1]. At their C-terminus, nesprins interact through a KASH domain with proteins of the nuclear membrane, including SUN and Lamin A/C [1]. Multiple isoforms of the 4 nesprin genes are produced by alternative transcriptional initiation, translation and splicing. Specifically, nesprin 1 and nesprin 2 giant contain an N-terminal calponin homology domain (CH) that binds to and co-localizes with F-actin [2]. These nesprins are necessary for transmission of stress to the nucleus and are also differentially regulated with myogenesis, neurogenesis and adipogenesis [3,4]. We previously demonstrated that addition of TGF-3 induced nuclear Lamin A/C reorganization and nuclear stiffening in mesenchymal stem cells (MSCs), along with increased cell contractility and altered accumulation of smaller nesprin isoforms [5,6]. This study sought to determine the importance of contractility in transmission of force to the nucleus and the effect of dynamic loading on the expression of the giant nesprin isoforms.
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8

Lavenne-Pardonge, E., C. Col-De Beys, R. Dion, R. Ponlot, and M. Moriau. "EFFECT OF ANTIAGGREGANT ON OCCLUSION OF SAPHENOUS GRAFT CORONARY BYPASS." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644823.

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Double blind study on 49 patients, 24receiving aspirine-dipyri-damole, 25 a placebo. In both groups 20 patients were followed during one year. The two groupsdid not differ according to age, sex and number of coronary bypass. In all the patients, Calparin (3 x 5000 U/day) was injected subcutanously the day before andthe 7 days after surgery. In the first group dipyridamole (25 mg/ kg) was injected during the same period. The second group received a placebo IV injection. Thereafter long acting dipyridamole (400 mg/day) and aspirin (200 mg/day) were given orally in the first group, placebo in the second one. Cardiac follow-up included E.C.G. and thallium at maximum exercise. Coronarography was performed only incase of reappearence of chest pain. No difference was found between the two groups for the coagulation parameters duringthe whole year of study. Statistically significant differences between the two groups were found during the same period for β-thromboglobulin, fibrino-peptide A and the ratio Δ+ βTG/Δ+ FPA. Plateletactivity, elevated in the placebo group, was kept in normal limits in the treated group. During the two first months for the placebo and during the first month for the treated group the ratio Δ+ βTG/Δ+ FPA decreased in all patients showing the importance at this time of plasmatic hypercoagulability compared to platelet hyperactivity. During the 12 months of the study 5 thrombotic accidents (25 %) were noted in the placebo group (2 myocardial infarctions, 2 occlusions of bypass, 1 case of cerebral arterial disease) and 2 (10 % in the treated group) (1 postoperative death, 1 myocardial infarction) (NS ; p =0,21). Our results lead to two conclusions : 1) Platelet antiaggregants may influencethe permeability of saphenous .graft coronary bypass. A careful study of platelet acti-r vity with eventual change of the drug used may improve the late resultsof surgery. 2) Association of anticoagulant therapy (anti-vitamin K) during the two first months after surgery could also be useful.
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Ishiguro, H., S. Higashiyama, C. Namikawa, I. Ohkubo, and M. Sasaki. "MAPPING OF FUNCTIONAL DOMAINS OF HUMAN HIGH MOLECULAR WEIGHT (HMW) AND LOW MOLECULAR WEIGHT (LMW) KININOGENS BY USING MURINE MONOCLONAL ANTIBODIES (MAbs)." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1642849.

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It has been widely known that HMW and LMW kininogens are the large potential sources of kinin in human blood, and that HMW kininogen also functions as a cofactor in the contact activation of blood coagulation. Recently, it has been demonstrated that the heavy chains of kininogens strongly inhibited a number of cysteine proteinases such as calpains, cathepsins, papain and ficin. We made an attempt at mapping of functional domains on the molecules of both kininogens by using MAbs.Thirty four MAbs raised against human HMW and LMW kininogens were screened by ELISA. By using HMW kininogen, kinin-free HMW kininogen, kinin and fragment 1.2 (fr 1.2)-free HMW kininogen, LMW kininogen, kinin-free LMW kininogen, heavy chain of LMW kininogen and light chains of both kininogens, the MAbs were characterized and.classified into four groups; [1] 20 MAbs reacted with heavy chain, a common region of HMW and LMW kininogens. These MAbs possessed the specificity for domain 1 (2 MAbs), domain 2 (2 MAbs), domain 3 (7 MAbs), and both domains 2 and 3 (7 MAbs) of the heavy chain; [2] 7 MAbs recognized the fr 1.2, a unique histidine-rich region; [3] 5 MAbs reacted with the light chain of HMW kininogen; [4] 2 MAbs recognized the light chain of LMW kininogen.Two MAbs, designated HKG H7 and H12, effectively inhibited the cysteine proteinase inhibitor activity of HMW and LMW kininogens and the others did not affect it. Further, the MAbs, which recognized the fr 1.2 or light chain of HMW kininogen, suppressed the clotting activity. Especially, 2 MAbs, named HKG L2 and L5, effectively suppressed the clotting activity of HMW kininogen. The former, which neutralized about 70% of the clotting activity, reacted specifically with fr 1.2 region of HMW kininogen, and the latter, which neutralized more than 90% of it, recognized the light chain of HMW kininogen. In the results of competition ELISA, fr 1.2 specific MAbs could be classified into 5 kinds of MAbs for recognition sites, and the light chain (HMW kininogen)-specific MAbs also could be classified into 3 kinds of MAbs. Further, 2 light chain (LMW kininogen)-specific MAbs were thought to recognize an identical antigenic site.
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10

McCarrick, Michael T., and Robert K. Rosencrance. "World’s First LM5000 to LM6000 Cogeneration Plant Repowering." In ASME Turbo Expo 2000: Power for Land, Sea, and Air. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/2000-gt-0190.

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With the introduction of GE’s latest and most efficient gas turbine, the LM6000 in 1992, and the end of production of GE’s LM5000 gas turbine in 1997, the concept of repowering aging LM5000 gas turbine powered cogeneration plants with LM6000 gas turbines was an idea that most LM5000 owners and operators dreamed about. The LM6000 is an ideal replacement for the LM5000 as they both have nearly the same mass flow and exhaust gas temperature (critical for Heat Recovery Steam Generator (HRSG) compatibility), are about the same physical weight and dimensions, and can be operated in the same power range. Also, as the LM6000 is a current production model, it has more readily available spare gas turbines and turbine parts, has a much improved heat rate, lower emissions level, and has an option (SPRINT), for added power. In December 1999, the UAE Oildale Energy Facility became the first plant to operate with a newly installed LM6000 in its former LM5000 package. (This March the second LM5000 to LM6000 repowering was completed for Calpine Corporation at their Greenleaf #1 Cogeneration Plant in Yuba City, CA.) Energy Services, Inc., GE’s authorized LM6000 repowering OEM, designed, engineered and project managed the repowering. This paper will present the reasons UAE decided to repower; discuss the technical challenges encountered with, and modifications made to, the GEC ELM-150 cogeneration plant to accommodate the LM6000; review the schedule; and provide the economic benefits of the improved heat rate and reliability of the LM6000.
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