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Query: UNIPROT:P08758 (
annexin V
)
9,383
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Acute tubular injury in sepsis is associated with proximal tubular epithelial cell (PTEC) detachment into the lumen leading to back-leakage of glomerular ultrafiltrate and tubule obstruction. Inflammatory cytokines, such as IL-1alpha, IFNgamma and TNFalpha, are important mediators in sepsis-induced acute renal failure, although their precise role is unclear. We used primary cultures of human PTEC to investigate the hypothesis that inflammatory cytokines exert cytotoxic effects and cause detachment of cells from adherent monolayers, possibly through the intermediate nitric oxide (NO). At 5 days post-confluence, PTEC monolayers were stimulated for 24 hours with IL-1alpha (10 ng/ml), IFNgamma (200 u/ml) and TNFalpha (10 ng/ml). Monolayer viability was assessed by a live/dead dual fluorescence labeling technique. Apoptosis within monolayers was determined by morphological examination and terminal deoxynucleotidyl transferase-mediated
dUTP
nick-end labeling (TUNEL). PTEC in supernatants were counted and then analyzed by flow cytometry, using propidium iodide to assess cell viability and
annexin V
labeling to determine apoptosis. Results (mean +/- SEM; monolayers, n = 4; cell counts, n = 3; flow cytometry, n = 2) are shown below (at test, p < 0.05). Monolayers Supernatants Viable necrotic% of cells apoptotic countsx104/ml viable necrotic% of cells apoptotic Unstimulated 99.0+/-0.5 1.0+/-0.5 0 8.0+/-0.6a 64.6+/-2.5a 26.7+/-1.9a 6.2+/-0.6a Stimulated 92.4+/-3.2 7.6+/-3.2 0 14.7+/-0.6a 37.9+/-0.05a 48.0+/-0.3a 14.1+/-0.35a Following cytokine stimulation, there were significantly increased numbers of shed cells in supernatants. This cell population demonstrated significant loss of viability with increased numbers of both necrotic and apoptotic cells, as compared to unstimulated PTEC supernatants. Cytokine-stimulated monolayers maintained viability with no significant cell necrosis and no evidence of apoptosis. Preliminary experiments with the NO synthase inhibitor L-NMMA show that it reduces the number of cytokine-induced shed cells to the levels found in unstimulated cells (8.0 +/- 1.0 x 104/ml), although the percentages of necrotic and apoptotic cells are unchanged from cytokine-stimulated PTEC (44% and 15%, respectively). In conclusion, inflammatory cytokines induce necrotic and apoptotic cell shedding from PTEC monolayers with maintenance of monolayer viability. Preliminary data suggest that NO plays a cytotoxic role in this process.
...
PMID:Inflammatory cytokines induce apoptotic and necrotic cell shedding from human proximal tubular epithelial cell monolayers 1035 8
HL-60 and MCF-7 cells were treated with 0.15 microM camptothecin (CPT) or with the solvent dimethylsulfoxide (DMSO) for the controls, for 2, 3 and 4 h or for 24, 48 and 72 h, respectively. The apoptotic index (AI) was then evaluated in parallel by the following flow cytometric methods: (1) double staining of unfixed cells with fluoresceinated
annexin V
and propidium iodide (PI), this after detachment by trypsinization in the case of MCF-7 cultures; (2) prefixation in 70% ethanol, extraction of degraded, low molecular weight DNA with 0.2 M phosphatecitrate buffer and analysis of the DNA content stained with PI; (3) TUNEL, i.e. labelling of DNA strand breaks with biotin-
dUTP
, followed by staining with streptavidin-fluorescein and counterstaining with PI. In HL-60 cells, the three methods gave similar results for the AI (3-4% in the controls and at 2 h of CPT treatment, and 35-43% at 3 and 4 h after CPT). This indicates that CPT-induced membrane alteration and DNA fragmentation occurred concomitantly in those cells. For MCF-7 cells, CPT-induced apoptosis developed more slowly, the AI, whether based on
annexin V
or on DNA content, remained unchanged at 24 h, then was increasing to 8% at 48 h and to 25% at 72 h of treatment. In these cells, the TUNEL index did not increase prior to 72 h, and the increase was minor (up to 9% vs. 2-3% in the controls) at 72 h of the treatment. This indicates that in MCF-7 cells DNA strand breaks cannot be effectively labelled, which may be due to inaccessibility of 3'-OH ends in the breaks to exogenous terminal deoxynucleotidyl transferase. The mechanism of endonucleolytic DNA fragmentation thus may be different, depending on the cell type.
...
PMID:Comparison of methods based on annexin-V binding, DNA content or TUNEL for evaluating cell death in HL-60 and adherent MCF-7 cells. 1037 1
Thymocytes and peripheral lymphocytes of BioBreeding (BB) diabetes-prone (BBDP) and diabetes-resistant (BBDR) rat were analysed by fluorescence-activated cell sorter (FACS). The number of CD4- CD8-, CD4+ CD8-, CD4- CD8+ and CD4+ CD8+ subsets was not different between BBDP and BBDR rat thymocytes, whereas spleen and lymph nodes in BBDP rats undergo severe T-cell lymphopenia. Notably, mature CD4- CD8+ [T-cell receptor (TCR)-alphabeta+ and CD5+] cells are certainly present in the BBDP rat thymus, unlike some previous reports, suggesting that the differentiation of CD4- CD8+ from CD4+ CD8+ cells occurs normally in the BBDP rat thymus. As a cause of peripheral T-cell lymphopenia we suspected apoptosis of recent thymic emigrants. By FACS analysis with fluorescein isothiocyanate-labelled
annexin V
, elevated apoptosis was evident in BBDP rat peripheral lymphocytes. Furthermore, terminal deoxynucleotidyl transferase-mediated
dUTP
-biotin nick end labelling (TUNEL) staining in BBDP rat splenic sections revealed that a number of TUNEL-positive cells were observed in the T-lymphocyte-rich area. From these results, we postulate that an abnormally elevated apoptosis of peripheral T lymphocytes, but not impaired thymocyte differentiation, is a cause of the peripheral T-cell lymphopenia in BBDP rats.
...
PMID:Elevated apoptosis of peripheral T lymphocytes in diabetic BB rats. 1059 93
We have demonstrated that a novel Ste20-related kinase, designated SLK, mediates apoptosis and actin stress fiber dissolution through distinct domains generated by caspase 3 cleavage. Overexpression of SLK in C2C12 myoblasts stimulated the disassembly of actin stress fibers and focal adhesions and induced apoptosis, as determined by
annexin V
binding and terminal deoxynucleotidyltransferase-mediated
dUTP
-biotin nick end labeling analysis. SLK was cleaved by caspase 3 in vitro and in vivo during c-Myc-, tumor necrosis factor alpha, and UV-induced apoptosis. Furthermore, cleavage of SLK released two domains with distinct activities: an activated N-terminal kinase domain that promoted apoptosis and cytoskeletal rearrangements and a C-terminus domain that disassembled actin stress fibers. Moreover, our analysis has identified a novel conserved region (termed the AT1-46 homology domain) that efficiently promotes stress fiber disassembly. Finally, transient transfection of SLK also activated the c-Jun N-terminal kinase signaling pathway. Our results suggest that caspase-activated SLK represents a novel effector of cytoskeletal remodeling and apoptosis.
...
PMID:Caspase 3 cleavage of the Ste20-related kinase SLK releases and activates an apoptosis-inducing kinase domain and an actin-disassembling region. 1061 Dec 47
The signal transduction pathway showing how androgen withdrawal induces apoptosis in androgen-dependent cells has not been clearly understood. In these studies, we focused on the behavior of tyrosine kinases in androgen-dependent cells and investigated its correlation with apoptosis and bcl-2 expression. We used SC2G, an androgen-dependent mouse mammary carcinoma cell line, which had been cloned from Shionogi Carcinoma 115 (SC115). When SC2G cells were cultured with herbimycin A (HMA), a potent tyrosine kinase inhibitor, the number of viable cells decreased significantly after 24 h. Terminal deoxyribonucleotidyltransferase-mediated
dUTP
-biotin nick end labeling and flow cytometric analysis of
annexin V
staining showed that HMA induced apoptosis of SC2G cells. The level of bcl-2 mRNA in SC2G cells was suppressed by HMA in a dose-dependent manner on RT-PCR. Preincubation with caspase inhibitors protected HMA-induced apoptosis of SC2G cells. When a human bcl-2 gene was transfected in SC2G cells and overexpressed, SC2G cells seemed to acquire tolerance for HMA. These data indicate that HMA-sensitive tyrosine kinase(s) can regulate apoptosis and inhibit bcl-2 expression in SC2G mouse androgen-dependent cells. Tyrosine kinase(s) seemed to be a member of signal transduction between androgen receptor activation and bcl-2 expression.
...
PMID:Tyrosine kinase inhibitors reduce bcl-2 expression and induce apoptosis in androgen-dependent cells. 1064 13
The present study was designed to investigate whether apoptosis occurs in early-stage vein grafts and to determine the mechanisms by which mechanical stress contributes to apoptosis in vascular smooth muscle cells (SMCs). Apoptosis in vessel walls of mouse vein grafts was confirmed by morphological changes and by terminal deoxynucleotidyl transferase-mediated
dUTP
-biotin nick end labeling (TUNEL). TUNEL(+) cells in vein grafts 1, 4, and 8 wk postoperatively was 13%, 29%, and 21%, respectively, and apoptosis occurred mainly in veins grafted to arteries, remaining unchanged in vein-to-vein grafts. When mouse, rat, and human arterial SMCs were cultured on a flexible membrane and subjected to cyclic strain stress, apoptosis was observed in a time- and strength-dependent manner. All three types of SMCs showed apoptotic death as confirmed by TUNEL, propidium iodide, and
annexin V
staining. To further study the signal pathways leading to apoptosis, activities of p38, a subfamily of mitogen-activated protein kinases (MAPKs), were determined. Mechanical stress resulted in p38 MAPK activation, reaching high levels within 8 min. SB 202190, a specific inhibitor for p38 MAPKs, prevented SMC apoptosis in response to mechanical stress. SMC lines stably transfected with a dominant negative rac, an upstream signal transducer, or overexpressing MAPK phosphatase-1, a negative regulator for MAPKs, completely inhibited mechanical stress stimulated p38 activation and abolished mechanical stress-induced apoptosis. Thus, we provide solid evidence that one of the earliest events in venous bypass grafts is apoptosis, in which mechanical stress-induced p38-MAPK activation is responsible for transducing signals leading to apoptosis.-Mayr, M., Li, C., Zou, Y., Huemer, U., Hu, Y., Xu, Q. Biomechanical stress-induced apoptosis in vein grafts involves p38 mitogen-activated protein kinases.
...
PMID:Biomechanical stress-induced apoptosis in vein grafts involves p38 mitogen-activated protein kinases. 1066 Apr 48
In the last decade, apoptosis (or programmed cell death) has become appreciated as an important process in the development of the cardiovascular system. Moreover, apoptosis contributes to the adaptation of the system to the environment. We are at the beginning of understanding its relevance to cardiovascular physiology and pathology. This understanding forms the key to implement apoptosis in diagnosis and therapy of cardiovascular diseases. New avenues for pharmacological intervention are expected to arise from the synergy of our knowledge about the molecular mechanisms of apoptosis, and how apoptosis integrates in the complex environment of the cardiovascular tissue. The latter strongly depends on techniques to measure apoptosis. Currently, we are facing a relative paucity in available techniques, covering both specificity and sensitivity, and furthermore allowing quantitative analysis, preferably in combination with morphology. This field, however, is rapidly evolving and is fed by the expanding knowledge about the molecular mechanisms of apoptosis. In this paper we will briefly review the available techniques to detect and/or quantify apoptosis. These methods are based on the analysis of cellular morphology, either by light- or electron microscopy, DNA fragmentation (TdT-mediated X-
dUTP
nick end labeling or in situ nick end labeling), or cytoplasmic and membrane changes. Furthermore, the advantages and limitations of these techniques for their use in cardiovascular research will be outlined. In the text we will refer to available reviews and protocols which discuss the techniques in more detail. The main part of this article will, however, focus on a recently introduced technique, the
Annexin V
-based apoptosis detection assay. The principle, characteristics, pro's and contra's of this new apoptosis detection assay will be discussed.
...
PMID:Markers of apoptosis in cardiovascular tissues: focus on Annexin V. 1072 76
The immunosuppressive cyclosporine A derivative, O-hydroxyethyl-D(Ser)(8)-cyclosporine (SDZ IMM 125), was examined for its ability to induce apoptosis in rat hepatocytes cultured for 4 or 20 h. Four hours after SDZ IMM 125 treatment, chromatin condensation and fragmentation, and the number of terminal deoxynucleotidyl transferase-mediated
dUTP
-biotin nick end labeled and
Annexin V
-positive cells increased dose dependently without any observable lactate dehydrogenase leakage. The activity of the cysteine protease, caspase-3, was increased, but not that of caspase-1 and -6. The specific caspase-3 inhibitor, Ac-Asp-Glu-Val-Asp-aldehyde, inhibited caspase-3 activation and attenuated SDZ IMM 125-induced apoptosis and lactate dehydrogenase leakage. After 20 h of SDZ IMM 125 incubation, the parameters of apoptosis were further increased. Decreased mitochondrial membrane potential (measured by rhodamine 123 uptake) and cytochrome c release went in parallel with ultrastructural mitochondrial changes, and might be regarded as early events that trigger the apoptotic cascade. Transmission electron microscopy showed cytoplasmic blebbing after 4 h of SDZ IMM 125 incubation. As observed by transmission electron microscopy, treatment with SDZ IMM 125 resulted in an increase in the number of necrotic cells after 20 h, but not after 4 h. Our findings suggest that in rat hepatocyte cultures, SDZ IMM 125 is a specific inducer of apoptosis after short-term incubation, and this overlaps with necrosis after longer treatment periods. It is very likely that the necrosis occurring later is the result of the early apoptotic events.
...
PMID:Induction of apoptosis by the O-hydroxyethyl-D(Ser)(8)-cyclosporine A derivative SDZ IMM 125 in rat hepatocytes. 1073 49
To investigate the mitomycin C-induced apoptotic cell death of fibroblasts, the primarily cultured human Tenon's capsule fibroblasts were exposed to a clinically used dosage of 0.4 mg/ml of mitomycin C for 5 minutes. TUNEL (TdT-mediated
dUTP
-biotin nick end labeling) assay and electron microscopic studies were performed to determine the extent of mitomycin C-induced apoptosis. A flow cytometric study was performed to quantify the apoptotic cell population over time. The TUNEL stains were positive and electron microscopy showed features of apoptotic cell death in some fibroblasts 3 and 5 days after treatment. Flow cytometric analysis using
Annexin V
-propidium iodide double staining detected apoptotic cells 3 days after treatment. These apoptotic cell populations increased at 4 days and were sustained for one week. This study revealed that the clinical effects of mitomycin C on fibroblasts may be mediated not only by antiproliferative but also apoptotic cell death to some degree. Therefore, the apoptotic cell death of fibroblasts induced by mitomycin C should be considered to properly understand the mechanism of wound healing after trabeculectomy with adjunctive mitomycin C.
...
PMID:Mitomycin C-induced apoptosis in cultured human Tenon's capsule fibroblasts. 1076 91
Peripheral blood mononuclear cells (PBMCs) obtained from patients with advanced melanoma but not from healthy individuals were found to undergo spontaneous ex vivo apoptosis upon incubation in medium. PBMCs were evaluated for evidence of apoptosis using
Annexin V
binding, caspase-3 activation, and DNA fragmentation (terminal deoxynucleotidyl transferase-mediated
dUTP
nick end labeling). PBMCs of patients with melanoma contained a significantly higher proportion (P = 0.0027) of spontaneously apoptotic cells than PBMCs of controls after 24-h incubation in medium alone. The relative proportion of activated Fas+ and tumor necrosis factor receptor 1-positive (TNFR1+) PBMCs was significantly higher in patients with melanoma than that observed in controls. To demonstrate that the TNF family of receptors and ligands was involved in this type of apoptosis, PBMCs were incubated in the presence of agonistic anti-Fas antibody (CH-11) or TNF-alpha. The proportion of terminal deoxynucleotidyl transferase-mediated
dUTP
nick end labeling-positive PBMCs undergoing spontaneous apoptosis was found to be comparable with that induced by CH-11 antibody or TNF-alpha. Three-color flow cytometry revealed that CD3+ Fas+ T cells were especially sensitive to apoptosis and were preprogrammed in vivo to die. Apoptosis occurred in all subsets of PBMCs but was significantly higher (P = 0.01) in the CD3+ CD8+ T-cell subset in patients relative to controls. In two patients with melanoma, who responded clinically to dendritic cell-based peptide vaccines, the proportion of apoptotic T cells was decreased by half after therapy. In patients who were treated previously with vaccination-based therapies, levels of T-cell apoptosis were lower than in the other melanoma patients. The observed accelerated death of T cells, which are activated and susceptible to apoptosis in patients with melanoma, may contribute to a rapid turnover of immune cells, resulting in a decreased immunocompetence.
...
PMID:Spontaneous apoptosis of CD8+ T lymphocytes in peripheral blood of patients with advanced melanoma. 1077 63
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