Search results for "BLAST"

Overexpression of apolipoprotein J in human fibroblasts protects against cytotoxicity and premature senescence induced by ethanol and tert-butylhydro…

2008

Human diploid fibroblasts (HDFs) exposed to subcytotoxic stresses under H2O2, tert-butylhydroperoxide (t-BHP), and ethanol (EtOH) undergo stress-induced premature senescence (SIPS) characterized by many biomarkers of HDFs replicative senescence. Among these biomarkers are a growth arrest, an increase in the senescence-associated β-galactosidase activity, a senescent morphology, an overexpression of p21waf-1 and the subsequent inability to phosphorylate pRb, the presence of the common 4977-bp mitochondrial deletion, and an increase in the steady-state level of several senescence-associated genes such as apolipoprotein J (apo J). Apo J has been described as a survival gene against cytotoxic s…

Down-Regulation of Ku Autoantigen, DNA-Dependent Protein Kinase, and Poly(ADP-ribose) Polymerase during Cellular Senescence

1997

During aging and cellular senescence mutations accumulate in genomic and mitochondrial DNA. Ku autoantigens, DNA-dependent protein kinase, and poly (ADP-ribose) polymerase have an essential role in DNA damage recognition. Our purpose was to find out whether cellular senescence of fibroblasts affects the protein components that recognize DNA damage and induce the repair process. We compared presenescent and replicatively senescent human WI-38 fibroblasts with each other and with SV-40 immortalized and serum-deficient quiescent WI-38 cells. Our results showed that replicative senescence significantly decreased the nuclear level of both p70 and p86 components of Ku autoantigen. SV-40 immortali…

Nicotine-induced FGF-2 mRNA in rat brain is preserved during aging

2004

Indirect trophic actions of nicotine on brain during aging are suggested from observations describing nicotine as a cognitive enhancer, increasing vigilance and improving learning and memory, and both in vitro and in vivo models have demonstrated neuroprotective effects of nAChR agonists. Previously, we have reported that an acute intermittent (-)nicotine treatment significantly increases fibroblast growth factor-2 (FGF-2) mRNA and protein in several brain regions of rat brain. The present study was designed to analyse if nicotine-induced FGF-2 expression in the rat brain was preserved during aging. Using in situ hybridization and quantitative RNase protection assay the present paper report…

Attenuation of NF-κB Signaling Response to UVB Light during Cellular Senescence

1999

The ability of cells to adapt to environmental stresses undergoes a progressive reduction during aging. NF-kappaB-mediated signaling is a major defensive system against various environmental challenges. The aim of this study was to find out whether replicative senescence affects the response of the NF-kappaB signaling pathway to UVB light in human WI-38 and IMR-90 fibroblasts. The exposure of early passage fibroblasts to UVB light inhibited the proliferation and induced a flat phenotype similar to that observed in replicatively senescent fibroblasts not exposed to UVB light. The UVB radiation dose used (153 mJ/cm2) did not induce apoptosis in either early or late passage WI-38 fibroblasts. …

Antidepressants are functional antagonists at the serotonin type 3 (5-HT3) receptor

2003

Antidepressants are commonly supposed to enhance serotonergic and/or noradrenergic neurotransmission by inhibition of neurotransmitter reuptake through binding to the respective neurotransmitter transporters or through inhibition of the monoamine oxidase. Using the concentration-clamp technique and measurements of intracellular Ca2+, we demonstrate that different classes of antidepressants act as functional antagonists at the human 5-HT3A receptor stably expressed in HEK 293 cells and at endogenous 5-HT3 receptors of rat hippocampal neurons and N1E-115 neuroblastoma cells. The tricyclic antidepressants desipramine, imipramine, and trimipramine, the serotonin reuptake inhibitor fluoxetine, t…

Antigenic cell wall mannoproteins in Candida albicans isolates and in other Candida species.

1991

Polyclonal antibodies (pAbs) and monoclonal antibodies (mAbs), raised against mannoprotein components from Candida albicans ATCC 26555 (serotype A) blastoconidia and mycelial cell walls, were used to investigate antigenic similarities among wall mannoproteins from other C. albicans serotype A and B strains, and from C. tropicalis and C. guilliermondii. Radioactively labelled walls isolated from cells grown at either 28 degrees C or 37 degrees C were digested with a beta-glucanase complex (Zymolyase 20T) to release cell-wall-bound mannoproteins. Numerous molecular species with different electrophoretic mobilities were released from the various isolates. Differences appeared to be related to …

Shedding of Membrane Vesicles Mediates Fibroblast Growth Factor-2 Release from Cells

2003

Fibroblast growth factor-2 (FGF-2), a polypeptide with regulatory activity on cell growth and differentiation, lacks a conventional secretory signal sequence, and its mechanism of release from cells remains unclear. We characterized the role of extracellular vesicle shedding in FGF-2 release. Viable cells released membrane vesicles in the presence of serum. However, in serum-free medium vesicle shedding was dramatically down-regulated, and the cells did not release FGF-2 activity into their conditioned medium. Addition of serum to serum-starved cells rapidly induced intracellular FGF-2 clustering under the plasma membrane and into granules that colocalized with patches of the cell membrane …

Ku factor is responsible of Hsp70 basal transcription in mouse mesoangioblasts

2008

H2O2 INDUCES NECROPTOSIS IN MESOANGIOBLAST STEM CELLS

2018

Stem cells are used in regenerative medicine, but their therapeutic efficacy is compromised by their huge death during the first days post-transplantation. Indeed, the microenvironment within damaged tissues is hostile for stem cell survival mainly due to oxidative stress. H2O2 may play a relevant role in inducing death of the injected cells. The aim of our study was to determine the mechanism of mesoangioblast (A6) cell death after an H2O2 treatment. FACS analysis with annV/PI showed that H2O2 induced a dose and time-dependent decrement in A6 viability. We have also found an increase in caspases 8, 9 and 3 activity after the treatment. To assess their involvement in cell death, the pan cas…

Mouse mesoangioblasts release Hsp70 in a controlled manner through membrane vesicle shedding

2009

Mesoangioblaststs (Mabs) are mesodermal stem cells associated with vessels which can differentiate into different mesoderm cell types. They have the property to cross endothelial barrier and when injected into circulation they localize into damaged tissues. A6 cells, a clone of mouse Mabs, express Hsp70 protein in physiological conditions and this synthesis may be required to answer to several intra- and/or extra-cellular needs. It was found that Hsp70 may be released outside from several type of cells, but its role remains still undefined. In order to clarify the reason of Hsp70 constitutive expression, we prepared several A6 clones with different levels of Hsp70 expression by stable RNA i…