Search results for "Fibronectin"
showing 10 items of 165 documents
Functional assessment of the quality of human hepatocyte preparations for cell transplantation.
2008
Hepatocyte transplantation is an alternative therapy to orthotopic liver transplantation for the treatment of liver diseases. Good quality freshly isolated or cryopreserved human hepatocytes are needed for clinical transplantation. However, isolation, cryopreservation, and thawing processes can seriously impair hepatocyte viability and functionality. The aim of the present study was to develop a fast and sensitive procedure to estimate the quality of hepatocyte preparations prior to clinical cell infusion. To this end, cell viability, attachment efficiency, and metabolic competence (urea synthesis and drug-metabolizing P450 activities) were selected as objective criteria. Viability of hepat…
Serum Irisin Concentrations in Severely Inflamed Patients
2020
AbstractIrisin is a recently discovered exercise-induced myokine that has been attributed the role of favoring white-to-brown adipose tissue trans-differentiation. We confirmed in a population-based cohort that irisin serum concentrations are independently correlated with the habitual level of physical activity, but we also observed an independent correlation with serum concentrations of high-sensitivity C-reactive protein (hs-CRP), thus suggesting that inflammation may influence irisin production. In order to investigate the association between irisin and inflammation, we measured serum irisin concentrations in a group of inflamed inpatients. We hypothesized that if an association between …
Serum irisin levels, precocious myocardial infarction, and healthy exceptional longevity.
2014
Abstract Background Skeletal muscles produce irisin. Growing controversy exists on the association between this myokine and chronic disease risk. On the basis of the potential protective effects that irisin could exert on both vascular function and skeletal muscle mass, we hypothesized that an elevated level of this molecule may contribute to successful aging. Methods Serum irisin levels were measured using enzyme-linked immunosorbent assay in disease-free centenarians, young healthy controls, and patients with precocious acute myocardial infarction. Results We found the highest levels of serum irisin in disease-free centenarians (35.3 ± 5.5 ng/mL) compared with young healthy controls (20.7…
Adhesive and invasive features in gliomas
2000
Summary This study aims at the in situ identification of factors mediating glioma cell invasion requiring adhesion, extracellular matrix degradation, and migration. Fortyfive gliomas (astrocytomas, glioblastomas, oligodendrogliomas, and mixed gliomas) were investigated for the immunohistochemical expression of the membrane protein CD44s, the basal lamina proteins laminin, collagen IV, and fibronectin, the lectin galectin-3 recognizing tenascin and N-CAM, as well as for the matrix-degrading enzymes metalloproteinases MMP-2, MMP-9, and cathepsin D. Besides vessels expressing basal lamina proteins, tenascin, MMP-2, MMP-9, and galectin-3, tumor cells revealed strong immunoreactivity for CD44s, …
In vitro effects of flunisolide on MMP-9, TIMP-1, fibronectin, TGF-beta1 release and apoptosis in sputum cells freshly isolated from mild to moderate…
2004
Corticosteroids play an important role in inflammation and remodelling of airways and are considered an important therapeutic target in asthma. Inflammation in asthma is characterized by a dysregulation of eosinophil apoptosis and of markers of airways remodelling. We evaluated the ability of flunisolide to inhibit in vitro the release of metalloproteinases-9 (MMP-9), tissue inhibitor metalloproteinases-1 (TIMP-1), transforming growth factor (TGF-beta) and fibronectin by sputum cells (SC) as well as to induce sputum eosinophil apoptosis.The SC, isolated from induced sputum samples of 12 mild-to-moderate asthmatics, were cultured for 24 h in the presence or absence of flunisolide (1, 10 and …
Dexamethasone modulates α2-macroglobulin and apolipoprotein E gene expression in cultured rat liver fat-storing (Ito) cells
1991
Fat-storing (Ito) cells are perisinusoidal liver cells thought to play a central role in vitamin A metabolism and fibrogenesis. Glucocorticoids have been shown to be beneficial in the treatment of certain types of liver diseases by delaying the development of cirrhosis. To study the regulatory effects of dexamethasone on Ito cell gene expression, Ito cells were isolated from normal rat liver and primary cultures were established. The effect of dexamethasone on the synthesis of α2-macroglobulin, apolipoprotein E, fibronectin and actin was examined. Protein synthesis was studied both at the protein level and at the RNA level by means of biosynthetic labeling, immunoprecipitation followed by s…
Functional Fibronectin Adsorption on Aptamer-Doped Chitosan Modulates Cell Morphology by Integrin-Mediated Pathway.
2019
A decisive step in cell-biomaterial interaction is represented by the adsorption of proteins at the interface, whose fine control may be useful to trigger proper cell response. To this purpose, we can selectively control protein adsorption on biomaterials by means of aptamers. Aptamers selected to recognize fibronectin dramatically enhance chitosan ability to promote cell proliferation and adhesion, but the underlying biological mechanism remains unknown. We supposed that aptamers contributed to ameliorate the adsorption of fibronectin in an advantageous geometrical conformation for cells, thus regulating their morphology by the proper activation of the integrin-mediated pathway. We investi…
Cleavage of endometrial α-integrins into their functional forms is mediated by proprotein convertase 5/6.
2012
Background Proprotein convertases (PCs) post-translationally activate a large number of protein precursors through limited cleavage. PC5/6 (PC6) in the human endometrium is tightly regulated during receptivity for embryo implantation. Integrins are transmembrane glycoproteins, some of which play an important role in the adhesive interactions between the trophoblast (blastocyst) and uterine epithelium at implantation. Integrins require PC cleavage for post-translational modification. We hypothesize that pro-integrin-αs in the endometrial epithelium are post-translationally cleaved by PC6 into functional subunits for the binding of blastocyst and adhesion of extracellular matrix proteins. Met…
αv-Class integrin binding to fibronectin is solely mediated by RGD and unaffected by an RGE mutation.
2020
Fibronectin (FN) is an essential glycoprotein of the extracellular matrix; binds integrins, syndecans, collagens, and growth factors; and is assembled by cells into complex fibrillar networks. The RGD motif in FN facilitates cell binding and fibrillogenesis through binding to α5β1 and αv-class integrins. However, whether RGD is the sole binding site for αv-class integrins is unclear. Most notably, substituting aspartate with glutamate (RGE) was shown to eliminate integrin binding in vitro, while mouse genetics revealed that FNRGE preserves αv-class integrin binding and fibrillogenesis. To address this conflict, we employed single-cell force spectroscopy, engineered cells, and RGD motif–defi…