Search results for "HSP70 Heat-Shock Proteins"
showing 10 items of 115 documents
Expression Profile of Stress Proteins, Intermediate Filaments, and Adhesion Molecules in Experimentally Denervated and Reinnervated Rat Facial Muscle
1997
The immunohistochemical profiles of ubiquitin, heat shock protein 70, alpha-B-crystallin, desmin, vimentin, neural cell adhesion molecule (N-CAM), and tenascin in rat facial muscle were studied after permanent denervation by transection of the facial plexus on one side and compared with findings after immediate reinnervation by hypoglossal-facial nerve anastomosis subsequent to transection on the contralateral side. Levator labii muscle samples were collected sequentially at 2, 6, 7, 10, 20, and 24 weeks after surgery. Normal levator labii muscle fibers showed physiological expression of desmin and alpha-B-crystallin. Denervated rat facial muscle displayed distinct up-regulation of ubiquiti…
HSP90 and HSP70: Implication in Inflammation Processes and Therapeutic Approaches for Myeloproliferative Neoplasms.
2015
Myeloproliferative neoplasms (MPN) are clonal stem cell disorders that lead to the excessive production of one or more blood cell lineages. It has been reported that, in most MPN, inflammatory cytokines are frequently increased, indicating that inflammation plays a crucial role in these disorders. Heat shock proteins (HSP) are induced in response to many stressful conditions from heat shock to hypoxia and inflammation. Besides their chaperone and cytoprotective functions, HSPs are key players during inflammation, hence the term “chaperokine.” Through their chaperone activity, HSP90, a stabilizer of many oncogenes (e.g., JAK2), and HSP70, a powerful antiapoptotic chaperone, tightly regulate …
HSP70 sequestration by free α-globin promotes ineffective erythropoiesis in β-thalassaemia
2014
International audience; β-Thalassaemia major (β-TM) is an inherited haemoglobinopathy caused by a quantitative defect in the synthesis of β-globin chains of haemoglobin, leading to the accumulation of free α-globin chains that form toxic aggregates. Despite extensive knowledge of the molecular defects causing β-TM, little is known of the mechanisms responsible for the ineffective erythropoiesis observed in the condition, which is characterized by accelerated erythroid differentiation, maturation arrest and apoptosis at the polychromatophilic stage. We have previously demonstrated that normal human erythroid maturation requires a transient activation of caspase-3 at the later stages of matur…
Heat Shock Proteins Alterations in Rheumatoid Arthritis
2022
Rheumatoid arthritis (RA) is a chronic inflammatory and autoimmune disease characterized by the attack of the immune system on the body’s healthy joint lining and degeneration of articular structures. This disease involves an increased release of inflammatory mediators in the affected joint that sensitize sensory neurons and create a positive feedback loop to further enhance their release. Among these mediators, the cytokines and neuropeptides are responsible for the crippling pain and the persistent neurogenic inflammation associated with RA. More importantly, specific proteins released either centrally or peripherally have been shown to play opposing roles in the pathogenesis of this dise…
Correction: Oncogenic extracellular HSP70 disrupts the gap-junctional coupling between capillary cells
2021
High levels of circulating heat shock protein 70 (HSP70) are detected in many cancers. In order to explore the effects of extracellular HSP70 on human microvascular endothelial cells (HMEC), we initially used gap-FRAP technique. Extracellular human HSP70 (rhHSP70), but not rhHSP27, blocks the gap-junction intercellular communication (GJIC) between HMEC, disrupts the structural integrity of HMEC junction plaques, and decreases connexin43 (Cx43) expression, which correlates with the phosphorylation of Cx43 serine residues. Further exploration of these effects identified a rapid transactivation of the Epidermal Growth Factor Receptor in a Toll-Like Receptor 4-dependent manner, preceding its in…
Pro-invasive stimuli and the interacting protein Hsp70 favour the route of alpha-enolase to the cell surface
2017
AbstractCell surface expression of alpha-enolase, a glycolytic enzyme displaying moonlighting activities, has been shown to contribute to the motility and invasiveness of cancer cells through the protein non-enzymatic function of binding plasminogen and enhancing plasmin formation. Although a few recent records indicate the involvement of protein partners in the localization of alpha-enolase to the plasma membrane, the cellular mechanisms underlying surface exposure remain largely elusive. Searching for novel interactors and signalling pathways, we used low-metastatic breast cancer cells, a doxorubicin-resistant counterpart and a non-tumourigenic mammary epithelial cell line. Here, we demon…
Heat shock proteins in fibrosis and wound healing: Good or evil?
2014
Heat shock proteins (HSPs) are key regulators of cell homeostasis, and their cytoprotective role has been largely investigated in the last few decades. However, an increasing amount of evidence highlights their deleterious effects on several human pathologies, including cancer, in which they promote tumor cell survival, proliferation and drug resistance. Therefore, HSPs have recently been suggested as therapeutic targets for improving human disease outcomes. Fibrotic diseases and cancer share several properties; both pathologies are characterized by genetic alterations, uncontrolled cell proliferation, altered cell interactions and communication and tissue invasion. The discovery of new HSP…
In vitro effect of cadmium and copper on separated blood leukocytes of Dicentrarchus labrax.
2013
The immunotoxic effects of heavy metals on blood leukocytes of sea bass (Dicentrarchus labrax) were examined. The cells, separated by a discontinuous Percoll-gradients, were exposed in vitro to various sublethal concentrations of cadmium and copper (10(-7) M, 10(-5) M, and 10(-3) M) and their immunotoxic effect was then evaluated by measuring neutral red uptake, MU assay, DNA fragmentation and Hsp70 gene expression. First of all, we demonstrated that the cells treated in vitro could incorporate Cd and Cu. A relationship between heavy metal exposure and dose-time-dependent alterations in responses of leukocytes from blood was found for both metals, but copper was more immunotoxic than cadmiu…
The Hsc/Hsp70 Co-Chaperone Network Controls Antigen Aggregation and Presentation during Maturation of Professional Antigen Presenting Cells
2011
The maturation of mouse macrophages and dendritic cells involves the transient deposition of ubiquitylated proteins in the form of dendritic cell aggresome-like induced structures (DALIS). Transient DALIS formation was used here as a paradigm to study how mammalian cells influence the formation and disassembly of protein aggregates through alterations of their proteostasis machinery. Co-chaperones that modulate the interplay of Hsc70 and Hsp70 with the ubiquitin-proteasome system (UPS) and the autophagosome-lysosome pathway emerged as key regulators of this process. The chaperone-associated ubiquitin ligase CHIP and the ubiquitin-domain protein BAG-1 are essential for DALIS formation in mou…
Long-Term Calorie Restriction Enhances Cellular Quality-Control Processes in Human Skeletal Muscle
2015
Calorie restriction (CR) retards aging, acts as a hormetic intervention, and increases serum corticosterone and HSP70 expression in rodents. However, less is known regarding the effects of CR on these factors in humans. Serum cortisol and molecular chaperones and autophagic proteins were measured in the skeletal muscle of subjects on CR diets for 3-15 years and in control volunteers. Serum cortisol was higher in the CR group than in age-matched sedentary and endurance athlete groups (15.6 ± 4.6 ng/dl versus 12.3 ± 3.9 ng/dl and 11.2 ± 2.7 ng/dl, respectively; p ≤ 0.001). HSP70, Grp78, beclin-1, and LC3 mRNA and/or protein levels were higher in the skeletal muscle of the CR group compared to…