Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01034 (cystatin C)
 3,397 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The lysosomal cysteine proteinase cathepsin B is shown to be secreted by ten human colon carcinoma cell lines and to accumulate in culture media as a latent enzyme. The cell lines also secrete a physiological inhibitor of cathepsin B, cystatin C. A significant correlation was found between secretion of the latent enzyme and the inhibitor (r = 0.755, P < 0.01). The aim of the present study was to modulate the respective secretion of the two antagonists to test whether or not latency of cathepsin B was due to the concomitant secretion of the inhibitor. SW480 colon carcinoma cells were treated with the acidotropic agent ammonium chloride, phorbol 12-myristate 13-acetate, and the inflammatory cytokines TGF-beta, TNF-alpha, and IL-1 beta. Ammonium chloride significantly increased latent cathepsin B levels without affecting the constitutive secretion of cystatin C. Phorbol 12-myristate 13-acetate induced a 4- to 5-fold increase in secreted latent cathepsin B, but did not alter significantly the accumulation of cystatin C in media. The cytokines, TGF-beta, TNF-alpha, and IL-1 beta, had no major effect on the expression of these two antagonists. Latent cathepsin B released from human carcinoma cells could be efficiently activated by neutrophil elastase at neutral pH. It is concluded that latent cathepsin B is a true proenzyme rather than an enzyme-inhibitor complex. In addition, our data from neutrophil elastase activation experiments indicate that a proteolytic system for activation of the tumor cell-secreted latent enzyme may exist in vivo.
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PMID:Latency of cathepsin B secreted by human colon carcinoma cells is not linked to secretion of cystatin C and is relieved by neutrophil elastase. 820 57

The pathogenesis of atherosclerosis and abdominal aortic aneurysm involves breakdown of the elastic laminae. Elastolytic cysteine proteases, including cathepsins S and K, are overexpressed at sites of arterial elastin damage, but whether endogenous local inhibitors counterbalance these proteases is unknown. We show here that, whereas cystatin C is normally expressed in vascular wall smooth muscle cells (SMCs), this cysteine protease inhibitor is severely reduced in both atherosclerotic and aneurysmal aortic lesions. Furthermore, increased abdominal aortic diameter among 122 patients screened by ultrasonography correlated inversely with serum cystatin C levels. In vitro, cytokine-stimulated vascular SMCs secrete cathepsins, whose elastolytic activity could be blocked when cystatin C secretion was induced by treatment with TGF-beta(1). The findings highlight a potentially important role for imbalance between cysteine proteases and cystatin C in arterial wall remodeling and establish that cystatin C deficiency occurs in vascular disease.
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PMID:Cystatin C deficiency in human atherosclerosis and aortic aneurysms. 1054 13

During mouse embryo implantation, trophoblast invasion is controlled in part by a balance of trophoblast-derived proteinases and uterine decidual proteinase inhibitors. Our work has focused on cystatin C, the secreted inhibitor of cathepsins B and L. We have previously shown that cystatin C is synthesized by the uterine decidua and localized to the cells in close contact with the trophoblast during implantation in vivo. In the work reported here we have established that decidualizing cultures show a similar upregulation of cystatin C. Using Northern and Western blotting and immunolocalization techniques both cystatin C mRNA and secreted protein increased with the morphological differentiation of stromal or decidual capsule cultures. In an effort to understand the regulation of cystatin C expression, decidual cells were analyzed under various culture conditions. Cystatin C expression was upregulated by increased cell density and by the presence of serum in the media. The growth factors TGF-beta(1) and EGF were found to induce cystatin C to levels comparable to serum stimulation. Co-culture with ectoplacental cones (EPCs) likewise induced expression and resulted in the localization of cystatin at the decidua:trophoblast interface. This work shows that decidualizing cultures are a good system to study cystatin C expression and that the expression is controlled in part by TGF-beta(1) and EGF signaling.
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PMID:Control and expression of cystatin C by mouse decidual cultures. 1180 49

We screened for factors upregulating glial fibrillary acidic protein (GFAP) promoter activity by functional cloning with an immature astrocyte cell line (HB108-10) harboring a GFAP-lacZ construct. One cDNA clone that repeatedly upregulated lacZ expression encoded cystatin C (CysC), a cysteine protease inhibitor. TGF-beta induced CysC and GFAP expression in AP-16 cells, an astrocyte progenitor-like cell line expressing GLAST (a glutamate transporter subtype specifically expressed in immature astrocytes). CysC gene expression started earlier than that of GFAP in the mouse forebrain. It started in the ventricular zone at a similar period as (or slightly after) GLAST expression, but before GFAP expression. Although previous data showed that CysC is involved in the maintenance of adult neural stem cells, our data indicate that it is involved in astrocyte differentiation during mouse brain development.
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PMID:Isolation of cystatin C via functional cloning of astrocyte differentiation factors. 1550 1

The differentiation program of skeletal muscle cells is exquisitely sensitive to secreted proteins. We developed a strategy to maximize the discovery of secreted proteins, using mass spectrometry-based proteomics, from cultured muscle cells, C2C12, grown in a serum-free medium. This strategy led to the identification of 80 nonredundant proteins, of which 27 were secretory proteins that were identified with a minimum of two tryptic peptides. A number of the identified secretory proteins are involved in extracellular matrix remodeling, cellular proliferation, migration, and signaling. A putative network of proteins involving matrix metalloproteinase 2, SPARC, and cystatin C that all interact with TGFbeta signaling has been postulated to contribute toward a functional role in the myogenic differentiation program.
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PMID:Identification of secreted proteins during skeletal muscle development. 1726 26

Whereas the prevalence and impact of vascular pathology in Alzheimer diease (AD) are well established, the role of vascular and Alzheimer pathologies in the progression of neurodegeneration and cognitive impairment in Parkinson disease (PD) is under discussion. A retrospective clinico-pathologic study of 100 patients with autopsy proven PD (including 44 cases with dementia/PDD) and 20 cases of dementia with Lewy bodies (DLB) confirmed essential clinical (duration of illness, Mini-Mental State Examination/MMSE, age at death) and morphologic differences between these groups; Lewy body Braak scores and Alzheimer pathologies (neuritic Braak stage, cortical Abeta plaque load, and generalized cerebral amyloid angiopathy or CAA) were significantly higher/more severe in DLB and PDD than in PD without dementia. Duration of illness showed no association to any of the examined pathologic parameters, while there was a moderate association between LB scores and neuritic Braak stages, the latter significantly increasing with age. Significant association between cerebrovascular lesions and neuritic Braak stage was seen in PDD but not in PD subjects without dementia. These data suggest an influence of Alzheimer-related lesions on the progression of the neurodegenerative process and, in particular, on cognitive decline in both PDD and DLB. On the other hand, both these factors in PD and DLB appear to be largely independent from coexistent vascular pathology, except in cases with severe cerebrovascular lesions or those related to neuritic AD pathology. Assessment of ApoE genotype in a small number of cases showed no significant differences in the severity of Abeta plaque load and CAA except for much lower intensities in non-demented epsilon3/3 patients. Despite increasing evidence suggesting synergistic reactions between alpha-synuclein (alphaSyn), tau and Abeta-peptides, the major protein markers of both AD and Lewy body diseases, and of both vascular pathology and AD, the molecular background and pathophysiological impact of these pathologies on the progression of neurodegeneration and development of cognitive decline in PD await further elucidation.
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PMID:Prevalence and impact of vascular and Alzheimer pathologies in Lewy body disease. 1827 24

NS0 cells proliferate without external supply of growth factors in protein-free media. We hypothesize that the cells produce their own factors to support proliferation. Understanding the mechanisms behind this autocrine regulation of proliferation may open for the novel approaches to improve animal cell processes. The following proteins were identified in NS0 conditioned medium (CM): cyclophilin A, cyclophilin B (CypB), cystatin C, D-dopachrome tautomerase, IL-25, isopentenyl-diphosphate delta-isomerase, macrophage migration inhibitory factor (MIF), beta(2)-microglobulin, Niemann pick type C2, secretory leukocyte protease inhibitor, thioredoxin-1, TNF-alpha, tumour protein translationally controlled 1 and ubiquitin. Further, cDNA microarray analysis indicated that the genes for IL-11, TNF receptor 6, TGF-beta receptor 1 and the IFN-gamma receptor were transcribed. CypB, IFN-alpha/beta/gamma, IL-11, IL-25, MIF, TGF-beta and TNF-alpha as well as the known growth factors EGF, IGF-I/II, IL-6, leukaemia inhibitory factor and oncostatin M (OSM) were excluded as involved in autocrine regulation of NS0 cell proliferation. The receptors for TGF-beta, IGF and OSM are however present in NS0 cell membranes since TGF-beta(1) caused cell death, and IGF-I/II and OSM improved cell growth. Even though no ligand was found, the receptor subunit gp130, active in signal transduction of the IL-6 like proteins, was shown to be essential for NS0 cells as demonstrated by siRNA gene silencing.
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PMID:Proliferation of NS0 cells in protein-free medium: the role of cell-derived proteins, known growth factors and cellular receptors. 1943 15

Cystatin C is a lowmolecular protein (13 kDa) that inhibits the activity of lysosomal cysteine proteinases with the strongest activity against cathepsin B and H. The recent experiments show that the level of cystatin C is independented of chronic and acute inflammatory process which frequently coexist with end stage renal diseases. Recent studies challange the theory because a higher concentration of cystatin C in serum correlated well with a higher concentration of inflammatory markers such as a CRP and fibrinogen in the patients. In vitro experiments on cultured monocytes and macrophages discovered that after stimulation by LPS and INF the expression of the cystatin C gene and synthesis of this protein was reduced. Cystatin C plays important modulatory function in regulation of the natural immunity, protecting our body against viruses, bacteries and parasites. Moreover, cystatin C binds the C4 component and modulates activation of the classical complement pathway. The experiments also show that cystatin C could influence non-specific immune response through the inhibition of the superoxide anion generation (respiratory burst), phagocytosis, chemotaxis and apoptosis of neutrophils. Similarly, the cystatin C can modulate the specific immune response through the inhibition of cathepsin S, bindining membrane receptors for TGF-beta or increasing MHC class II expression on dendritic cells.
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PMID:[Cystatin C--modulator of immune processes]. 2138 61