Search results for "caspase"
showing 10 items of 390 documents
Apoptosis-related Proteins in Skeletal Muscle Fibers of Spinal Muscular Atrophy
1997
There is evidence that apoptosis in spinal muscular atrophies (SMA) is not restricted to motor neurons but also affects muscle fibers. Studying the expression of several apoptosis-associated proteins we found constant expression of bax in muscle fibers, which promoted cell death. The expression of bax correlated with defective innervation of muscle fibers was also indicated by upregulation of N-CAM. While in early-onset SMA atrophic as well as normo- and hypertrophic muscle fibers displayed expression of bax, muscle fibers in late-onset SMA and peripheral neuropathies showed bax-expression only in atrophic fibers. Other investigated apoptosis-associated factors comprised interleukin-1 beta …
NF-κB protects Behçet's disease T cells against CD95-induced apoptosis up-regulating antiapoptotic proteins
2005
Objective To determine whether prolongation of the inflammatory reaction in patients with Behcet's disease (BD) is related to apoptosis resistance and is associated with the up-regulation of antiapoptotic factors. Methods The percentage of cell death was evaluated by flow cytometry in peripheral blood mononuclear cells from 35 patients with BD and 30 healthy volunteers. The expression levels of antiapoptotic factors and NF-κB regulatory proteins were measured using Western blotting and immunohistochemical analyses. To down-regulate NF-κB nuclear translocation, BD T lymphocytes were exposed in vitro to thalidomide and subjected to transfection with NF-κB small interfering RNA. Results Althou…
Vascular endothelial growth factor expression in nasal polyps of aspirin-intolerant patients.
2012
Objective To study differences between aspirin-tolerant patients and aspirin-intolerant patients concerning vascular endothelial growth factor (VEGF) expression. Recent publications strongly suggest the involvement of VEGF and its receptors in the pathophysiologic process of nasal polyps. Design We subjected 43 polyp specimens to semiquantitative immunohistochemical analysis. We quantified VEGF and its receptors (Flk, Flt, and neuropilin) in all samples. To gain insight into potential VEGF-mediated cellular responses, we determined proliferative (Ki67) and apoptotic (caspase 3) indices. Patients Polyp samples were obtained from 22 aspirin-intolerant patients and from 21 aspirin-tolerant pat…
Control of target cell survival in thyroid autoimmunity by T helper cytokines via regulation of apoptotic proteins
2000
After autoimmune inflammation, interactions between CD95 and its ligand (CD95L) mediate thyrocyte destruction in Hashimoto's thyroiditis (HT). Conversely, thyroid autoimmune processes that lead to Graves' disease (GD) result in autoantibody-mediated thyrotropin receptor stimulation without thyrocyte depletion. We found that GD thyrocytes expressed CD95 and CD95L in a similar manner to HT thyrocytes, but did not undergo CD95-induced apoptosis either in vivo or in vitro. This pattern was due to the differential production of TH1 and TH2 cytokines. Interferon gamma promoted caspase up-regulation and CD95-induced apoptosis in HT thyrocytes, whereas interleukin 4 and interleukin 10 protected GD …
Lower apoptosis rate in human cumulus cells after administration of recombinant luteinizing hormone to women undergoing ovarian stimulation for in vi…
2007
Objective: To investigate the effects of recombinant (r-) LH supplementation in “low responder” patients undergoing ovarian stimulation with r-FSH for an IVF program. The apoptosis rate in cumulus cells was used as an indicator of oocyte quality. Design: Comparison of the rate of DNA fragmentation and caspase-3 activity in cumulus cells in women stimulated with r-LH and r-FSH, versus patients treated with r-FSH alone (control). Setting: In vitro fertilization (IVF) laboratory. Patient(s): Forty patients undergoing assisted fertilization programs treated with a GnRH agonist, or r-FSH treatment begun on day 3 of the cycle (control). In the r-LH group, from day 8 of gonadotropin stimulation, 1…
β-Amyloid-induced activation of Caspase-3 in primary cultures of rat neurons
2000
It is known that beta-amyloid peptide (Abeta) contributes to the neurodegeneration in Alzheimer's disease (AD) and operates through activation of an apoptotic pathway. Apoptotic signal is driven by a family of cysteine proteases called caspases. The beta-amyloid precursor protein (APP) is directly and efficiently cleaved by caspases during apoptosis, resulting in elevated beta-amyloid peptide formation. Cerebellar neurons from rat pups were treated with the aged Abeta(25-35) at 1 and 5 microM and fluorescence assays of caspase activity performed over 4 days. We observed an increase in caspase activity after 48 h treatment in both 1 and 5 microM treated cells, then (72-96 h) caspase activity…
The sea urchin embryo: a model to study Alzheimer's beta amyloid induced toxicity.
2009
Abstract Alzheimer’s disease (AD) is the most common form of dementia. The cause of AD is closely related to the accumulation of amyloid beta peptide in the neuritic plaques. The use of animal model systems represents a good strategy to elucidate the molecular mechanism behind the development of this pathology. Here we use the Paracentrotus lividus embryo to identify molecules and pathways that can be involved in the degenerative process. As a first step, we identified the presence of an antigen related to the human APP, called Pl APP. This antigen, after gastrula stage, is processed producing a polypeptide of about 10 kDa. By immunohistochemistry we localized the Pl APP antigen in some ser…
Detection of mitochondrial electron chain carrier redox status by transhepatic light intensity during rat liver reperfusion.
2003
The aim of the study was to investigate mitochondrial electron transfer during rat liver reperfusion after cold storage and hypothermic machine perfusion. Livers from male Brown Norway rats were preserved (UW) for 10h either by cold storage (CS) or by hypothermic oxygenated perfusion extracorporal (HOPE). Transhepatic photometric analysis allowed determination of the redox status of mitochondrial cytochromes during preservation, rewarming and reperfusion. Mitochondrial electron chain carriers were inhibited at different sites with rotenone and cyanide in some experiments. reversed transcriptional polymerase chain reaction (RT-PCR) was performed after reperfusion concerning transcription of …
Resistance to Gemcitabine in a Lymphoma Cell Line Resistant to Fas-mediated Apoptosis
2004
BACKGROUND: The T-cell lymphoma cell line HuT78B1, selected for resistance to Fas-mediated apoptosis, resulted unexpectedly resistant to the apoptotic and cytotoxic effects of gemcitabine (dFdC). We investigated whether this resistance was due to the impairment of the Fas/Fas-ligand (FasL) system. MATERIALS AND METHODS: dFdC effects were studied in HuT78B1 and in the parental Fas-sensitive HuT78 cells exposed to inhibitors of the Fas/FasL system. RESULTS: FasL- and Fas-blocking antibodies did not interfere with dFdC-induced apoptosis in HuT78 cells, whereas inhibitors of caspase-8, -9, -1 or -3 had partial inhibitory effects. Notably, in HuT78B1 cells there was a markedly reduced dFdC accum…
Toward a Rational Design of Polyamine-Based Zinc-Chelating Agents for Cancer Therapies.
2020
In vitro viability assays against a representative panel of human cancer cell lines revealed that polyamines L1a and L5a displayed remarkable activity with IC50 values in the micromolar range. Preliminary research indicated that both compounds promoted G1 cell cycle arrest followed by cellular senescence and apoptosis. The induction of apoptotic cell death involved loss of mitochondrial outer membrane permeability and activation of caspases 3/7. Interestingly, L1a and L5a failed to activate cellular DNA damage response. The high intracellular zinc-chelating capacity of both compounds, deduced from the metal-specific Zinquin assay and ZnL2+ stability constant values in solution, strongly sup…