Search results for "Acellular"
showing 10 items of 1986 documents
Meprin β: A novel regulator of blood–brain barrier integrity
2020
The metalloprotease meprin β (Mep1b) is capable of cleaving cell-adhesion molecules in different tissues (e.g. skin, kidney and intestine) and is dysregulated in several diseases associated with barrier breakdown (Alzheimer´s disease, kidney disruption, inflammatory bowel disease). In this study, we demonstrate that Mep1b is a novel regulator of tight junction (TJ) composition and blood–brain barrier (BBB) integrity in brain endothelium. In Mep1b-transfected mouse brain endothelial cells (bEnd.3), we observed a reduction of the TJ protein claudin-5, decreased transendothelial electrical resistance (TEER) and an elevated permeability to paracellular diffusion marker [14C]-inulin. Analysis o…
Distribution of Cartilage Proteoglycan (Aggrecan) Core Protein and Link Protein Gene Expression during Human Skeletal Development
1991
The distribution of cartilage proteoglycan core protein (aggrecan) and cartilage proteoglycan link protein was investigated by in situ hybridization during different stages of human skeletal development. Aggrecan and link protein expression were confined to chondrocytes of the developing skeleton and other cartilaginous structures. Distribution and intensity of the signal was identical with aggrecan as compared to link protein probes. Parallel to the calcification of cartilaginous matrix, chondrocytes of this area lost the expression of aggrecan and link protein specific mRNA and stayed negative throughout the following stages of skeletal development. Highest expression was found in the low…
DHEA-Bodipy–a functional fluorescent DHEA analog for live cell imaging
2009
International audience; The androgen dehydroepiandrosterone (DHEA) has been reported to protect neuronal cells against dysfunction and apoptosis. Several signaling pathways involved in these effects have been described but little is known about the intracellular trafficking of DHEA. We describe design, synthesis and characterization of DHEA-Bodipy, a novel fluorescent DHEA analog. DHEA-Bodipy proved to be a functional DHEA derivative: DHEA-Bodipy (i) induced estrogen receptor α-mediated gene activation, (ii) protected PC12 rat pheochromocytoma cells against serum deprivation-induced apoptosis, and (iii) induced stress fibers and focal adhesion contacts in SH-SY5Y human neuroblastoma cells. …
Brain Tumor-Derived Extracellular Vesicles as Carriers of Disease Markers: Molecular Chaperones and MicroRNAs
2020
Primary and metastatic brain tumors are usually serious conditions with poor prognosis, which reveal the urgent need of developing rapid diagnostic tools and efficacious treatments. To achieve these objectives, progress must be made in the understanding of brain tumor biology, for example, how they resist natural defenses and therapeutic intervention. One resistance mechanism involves extracellular vesicles that are released by tumors to meet target cells nearby or distant via circulation and reprogram them by introducing their cargo. This consists of different molecules among which are microRNAs (miRNAs) and molecular chaperones, the focus of this article. miRNAs modify target cells in the…
Exposure to cadmium chloride influences astrocyte-elevated gene-1 (AEG-1) expression in MDA-MB231 human breast cancer cells
2011
Abstract It is known that cadmium (Cd) is able to regulate gene expression, drastically affecting the pattern of transcriptional activity and intracellular signalization in normal and pathological human cells. We have already shown that Cd exerts a cytotoxic effect on neoplastic MDA-MB231 cells from the human breast, which is characterized by the onset of a “non-classical” apoptotic kind of death, impairment of mitochondrial activity and drastic changes in gene expression pattern. In the present study, employing a combination of conventional and differential display-PCR techniques, immunocytochemical, ELISA and Western analyses, we extended the knowledge on the transcriptional modulation ex…
Effects of cadmium chloride on some mitochondria-related activity and gene expression of human MDA-MB231 breast tumor cells.
2007
It was reported that cadmium is able to exert a cytotoxic effect on tumor MDA-MB231 cells, which shows signs of "non-classical" apoptosis and is characterized by drastic changes in gene expression pattern. In this study, we have extended our knowledge of metal-breast cancer cell interactions by analyzing some mitochondria-related aspects of the stress response to CdCl(2) at either 5 or 50 microM 24- or 96-h exposure, by cytochemical, conventional PCR and Northern/Western blot techniques. We demonstrated that (i) no modification of the mitochondrial mass was detectable due to CdCl(2) exposure; (ii) the respiration activity appeared to be increased after 96-h exposures, while the production o…
Cigarette smoke alters IL-33 expression and release in airway epithelial cells
2014
AbstractAirway epithelium is a regulator of innate immune responses to a variety of insults including cigarette smoke. Cigarette smoke alters the expression and the activation of Toll Like Receptor 4 (TLR4), an innate immunity receptor. IL-33, an alarmin, increases innate immunity Th2 responses. The aims of this study were to explore whether mini-bronchoalveolar lavage (mini-BAL) or sera from smokers have altered concentrations of IL-33 and whether cigarette smoke extracts (CSE) alter both intracellular expression (mRNA and protein) and release of IL-33 in bronchial epithelial cells. The role of TLR4 in the expression of IL-33 was also explored.Mini-BALs, but not sera, from smokers show red…
Cyclic AMP-mediated upregulation of the expression of neuronal NO synthase in human A673 neuroepithelioma cells results in a decrease in the level of…
2004
The expression level of neuronal nitric oxide synthase (nNOS) can vary depending on the (patho)physiological conditions. Here we document a marked induction of nNOS mRNA, protein, and total NO production in response to dibutyryl cyclic AMP (db-cAMP) in human A673 neuroepithelial cells. However, the upregulation of nNOS was associated with a decreased level of production of bioactive NO and by an increase in the level of generation of reactive oxygen species (ROS). ROS production could be prevented by the NOS inhibitor L-NAME, suggesting nNOS itself is involved in ROS generation. Sepiapterin supplementation of db-cAMP-treated A673 cells could restore full bioactive NO production, most likely…
Rapamycin stimulates arginine influx through CAT2 transporters in human endothelial cells
2007
In endothelial cells Tumor Necrosis Factor-alpha (TNFalpha) stimulates arginine transport through the increased expression of SLC7A2/CAT2 transcripts. Here we show that also rapamycin, an inhibitor of mTOR kinase, stimulates system y(+)-mediated arginine uptake in human endothelial cells derived from either saphenous (HSVECs) or umbilical veins (HUVECs). When used together with TNFalpha, rapamycin produces an additive stimulation of arginine transport in both cell models. These effects are observed also upon incubation with AICAR, a stimulator of Adenosine-Monophosphate-dependent-Protein Kinase (AMPK) that produces a rapamycin-independent inhibition of the mTOR pathway. Rapamycin increases …
Plasma membrane and lysosomal localization of CB1 cannabinoid receptor are dependent on lipid rafts and regulated by anandamide in human breast cance…
2005
AbstractIn this report we show, by confocal analysis of indirect immunofluorescence, that the type-1 cannabinoid receptor (CB1R), which belongs to the family of G-protein-coupled receptors, is expressed on the plasma membrane in human breast cancer MDA-MB-231 cells. However, a substantial proportion of the receptor is present in lysosomes. We found that CB1R is associated with cholesterol- and sphyngolipid-enriched membrane domains (rafts). Cholesterol depletion by methyl-β-cyclodextrin (MCD) treatment strongly reduces the flotation of the protein on the raft-fractions (DRM) of sucrose density gradients suggesting that CB1 raft-association is cholesterol dependent. Interestingly binding of …