Search results for " shock"
showing 10 items of 691 documents
Heat shock proteins: essential proteins for apoptosis regulation
2008
Abstract Many different external and intrinsic apoptotic stimuli induce the accumulation in the cells of a set of proteins known as stress or heat shock proteins (HSPs). HSPs are conserved proteins present in both prokaryotes and eukaryotes. These proteins play an essential role as molecular chaperones by assisting the correct folding of nascent and stress-accumulated misfolded proteins, and by preventing their aggregation. HSPs have a protective function, that is they allow the cells to survive to otherwise lethal conditions. Various mechanisms have been proposed to account for the cytoprotective functions of HSPs. Several of these proteins have demonstrated to directly interact with compo…
Short-term exposure to cadmium affects the expression of stress response and apoptosis-related genes in immortalized epithelial cells from the human …
2009
Abstract It is known that cadmium (Cd) evokes cell responses that not only involve protective reactions against toxicity but also induces cell death. Increasing interest has been recently focused on the elucidation of the cellular and molecular aspects of Cd-dependent regulation of gene expression in different model systems. Here, we examined the effects of short-term (24 h) exposure of immortalized non-tumoral HB2 cells from human breast epithelium to CdCl2 at 50 μM concentration, corresponding to the IC50 for this time of incubation. The possible occurrence of apoptosis-related events was evaluated via analysis of the physical state of the DNA and of the membrane localization of phosphaty…
Toxic effects induced by vanadium on sea urchin embryos
2020
Vanadium, a naturally occurring element widely distributed in soil, water and air, has received considerable interest because its compounds are often used in different applications, from industry to medicine. While the possible medical use of vanadium compounds is promising, its potential harmful effects on living organisms are still unclear. Here, for the first time, we provide a toxicological profile induced by vanadium on Paracentrotus lividus sea urchin embryos, reporting an integrated and comparative analysis of the detected effects reflecting vanadium-toxicity. At the morphological level we found a dose-dependent induction of altered phenotypes and of skeletal malformations. At the mo…
Assessment of Endoplasmic Reticulum Stress and the Unfolded Protein Response in Endothelial Cells
2011
In the vascular wall, the most inner cell layer that separates the blood from organelles is comprised of only a single layer of endothelial cells (ECs). This cell type is fundamental to a large variety of processes, ranging from blood coagulation and interaction with inflammatory cells to cardiovascular diseases such as hypertension, diabetes, and atherosclerosis. Dysfunction of ECs is often causally linked to these processes such that research exploring such events attracted much attention. Damage of ECs and subsequent disruption of the intact endothelial barrier can result not only from oxidative stress, but also from conditions that stress the endoplasmic reticulum (ER) and induce a sign…
Extracorporeal shock wave-mediated changes in proliferation, differentiation, and gene expression of human osteoblasts.
2008
The goal of this study was to determine whether cell proliferation, differentiation, and gene expression of primary human osteoblasts (hOB) are influenced by shock wave application (SWA).Osteoblast cultures were isolated from cancellous bone fragments and treated with 500 impulses of energy flux densities of 0.06 mJ/mm, 0.18 mJ/mm, 0.36 mJ/mm, and 0.50 mJ/mm. Twenty-four hours and 96 hours after SWA cell proliferation, alkaline phosphatase activity, and mineralization were analyzed. The global gene expression profiling was determined 96 hours after SWA employing Affymetrix HG-U133A microarrays.After 24 hours, hOB showed a dose-dependent increase in cell proliferation from 68.7% (at 0.06 mJ/…
Heat shock proteins in hematopoietic malignancies
2012
Inducible heat shock proteins are molecular chaperones whose expression is increased after many different types of stress. They have a protective function helping the cell to cope with lethal conditions. Their basal expression is low in nonstressed, normal and nontransformed cells. However, in cancer cells and particularly in hematological malignancies, they are surprisingly abundant. Malignant cells have to rewire their metabolic requirements and therefore have a higher need for chaperones. This cancer cell addiction for HSPs is the basis for the use of HSP inhibitors in cancer therapy. HSPs have been shown to interact with different key apoptotic proteins. As a result, HSPs can essentiall…
Heat Shock Proteins: Cell Protection through Protein Triage
2010
Heat shock proteins (HSPs) are chaperones that catalyze the proper folding of nascent proteins and the refolding of denatured proteins. The ubiquitin-proteasome system is an error-checking system that directs improperly folded proteins for destruction. A coordinated interaction between the HSPs (renaturation) and the proteasome (degradation) must exist to assure protein quality control mechanisms. Although it still remains unknown how the decision of folding vs. degradation is taken, many pieces of evidence demonstrate that HSPs interact directly or indirectly with the proteasome, assuring quite selectively the proteasomal degradation of certain proteins under stress conditions. In this rev…
Curcumin Affects HSP60 Folding Activity and Levels in Neuroblastoma Cells.
2020
The fundamental challenge in fighting cancer is the development of protective agents able to interfere with the classical pathways of malignant transformation, such as extracellular matrix remodeling, epithelial−mesenchymal transition and, alteration of protein homeostasis. In the tumors of the brain, proteotoxic stress represents one of the main triggering agents for cell transformation. Curcumin is a natural compound with anti-inflammatory and anti-cancer properties with promising potential for the development of therapeutic drugs for the treatment of cancer as well as neurodegenerative diseases. Among the mediators of cancer development, HSP60 is a key factor for the maintenance of…
Biotechnical applications of small heat shock proteins from bacteria.
2012
The stress responses of most bacteria are thought to involve the upregulation of small heat shock proteins. We describe here some of the most pertinent aspects of small heat shock proteins, to highlight their potential for use in various applications. Bacterial species have between one and 13 genes encoding small heat shock proteins, the precise number depending on the species considered. Major efforts have recently been made to characterize the protein protection and membrane stabilization mechanisms involving small heat shock proteins in bacteria. These proteins seem to be involved in the acquisition of cellular heat tolerance. They could therefore potentially be used to maintain cell via…
Complementation of Saccharomyces cerevisiae mutationsin genes involved in translation and protein folding (EFB1 and SSB1)with Candida albicans cloned…
2000
We have demonstrated that the expression of Candida albicans genes involved in translation and protein folding (EFB1 and SSB1) complements the phenotype of Saccharomyces cerevisiae mutants. The elongation factor 1beta (EF-1beta) is essential for growth and efb1 S. cerevisiae null mutant cells are not viable; however, viable haploid cells, carrying the disrupted chromosomal allele of the S. cerevisiae EFB1 gene and pEFB1, were isolated upon sporulation of a diploid strain which was heterozygous at the EFB1 locus and transformed with pEFB1 (a pEMBLYe23 derivative plasmid containing an 8-kb DNA fragment from the C. albicans genome which contains the EFB1 gene). This indicates that the C. albic…