Characterization of cell volume loss in CEM-C7A cells during dexamethasone-induced apoptosis

1996 ◽  
Vol 270 (4) ◽  
pp. C1190-C1203 ◽  
Author(s):  
R. S. Benson ◽  
S. Heer ◽  
C. Dive ◽  
A. J. Watson
Keyword(s):  
Cell Volume ◽  
Chromatin Condensation ◽  
Buoyant Density ◽  
Second Phase ◽  
Volume Loss ◽  
Cell Shrinkage ◽  
Intact Cells ◽  
Nuclear Changes ◽  
Induced Apoptosis ◽  
Cell Sizing

A reduction in cell volume is a fundamental feature of apoptosis. We have characterized changes in cell volume, together with nuclear changes, occurring in dexamethasone-induced apoptosis in CEM-C7A lymphoblastoid cells. Cell volume was measured by electronic cell sizing and flow cytometry, and two distinct phases of volume loss were observed. The first phase began 12 h after addition of dexamethasone (5 microM) and progressed until 36 h when chromatin condensation was detected in intact cells. Removal of dexamethasone before 36 h (the precommitment period) resulted in reversal of the volume decrease and prevented the appearance of nuclear changes. Cell shrinkage in the first 24 h of dexamethasone exposure was associated with a net loss of potassium but no change in cellular buoyant density. There were no significant differences in the rates of volume recovery after either hypertonic or hypotonic stimuli. These observations favor a mechanism of cell shrinkage involving loss of the entire cytoplasmic contents, possibly following proteolysis, rather than loss of only osmolytes and water. The second phase of volume loss was coincident with chromatin condensation and was associated with cellular fragmentation and a reduction in cellular density. We conclude that volume loss in this model of apoptosis is mediated by multiple mechanisms that are both dependent and independent of cellular fragmentation.

Characterization of Cell Volume Loss during Dexamethasone-Induced Apoptosis

1995 ◽  
Vol 89 (s33) ◽  
pp. 5P-5P
Author(s):  
RSP Benson ◽  
S Heer ◽  
C Dive ◽  
AJM Watson
Keyword(s):  
Cell Volume ◽  
Volume Loss ◽  
Induced Apoptosis

Ammonia-induced apoptosis is accelerated at higher pH in gastric surface mucous cells

2002 ◽  
Vol 283 (4) ◽  
pp. G986-G995 ◽  
Author(s):  
Hideo Suzuki ◽  
Akinori Yanaka ◽  
Takeshi Shibahara ◽  
Hirofumi Matsui ◽  
Akira Nakahara ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Cytochrome C ◽  
Chromatin Condensation ◽  
Mucosal Injury ◽  
Nuclear Chromatin ◽  
Gastric Epithelial Cells ◽  
Mucous Cells ◽  
Cell Shrinkage ◽  
H Pylori ◽  
Induced Apoptosis

Gastric luminal ammonia produced by Helicobacter pylori has been shown to cause gastric mucosal injury. This study was conducted to examine the mechanisms by which gastric luminal ammonia causes apoptosis of gastric epithelial cells. Monolayers of GSM06 cells, developed from murine gastric surface mucous cells, were cultured in the absence or presence of 10–30 mM NH4Cl at ambient pH of 5.0, 6.0, and 7.0. In the presence of luminal NH4Cl, GSM06 cells showed 1) cell shrinkage and nuclear chromatin condensation, 2) DNA fragmentation into oligonucleosomes, 3) leakage of cytochrome c into cytosolic fraction without affecting bax expression, and 4) increases in activity of caspases-3 and -9. These changes were accentuated when the cells were cultured at pH 7.0. In the absence of NH4Cl, none of these changes was detected at any pH examined. These results suggest that gastric luminal ammonia, at concentrations detected in H. pylori-infected subjects, induces apoptosis of gastric epithelial cells by release of cytochrome c from mitochondria, followed by activation of caspases-9 and -3, especially at higher ambient pH.

scholarly journals Cytosolic protein concentration is the primary volume signal in dog red cells.

1991 ◽  
Vol 98 (5) ◽  
pp. 881-892 ◽  
Author(s):  
G C Colclasure ◽  
J C Parker
Keyword(s):  
Cell Volume ◽  
Surface Area ◽  
Protein Concentration ◽  
Hemoglobin Concentration ◽  
Red Cells ◽  
Solid Concentration ◽  
Intracellular Protein ◽  
Cell Shrinkage ◽  
Intact Cells ◽  
Resealed Ghosts

It is not known whether the activation of Na/H exchange by shrinkage in dog red cells is due to the packing of cell contents or a change in cell configuration. To make this distinction we prepared resealed ghosts that resembled intact cells in hemoglobin concentration and surface area, but had one-third their volume. A shrinkage-induced, amiloride-sensitive Na flux in the ghosts was activated at a much smaller volume in the ghosts than in the intact cells, but at the same concentration (by weight) of dry solids in both preparations. Na/H exchange in ghosts containing a mixture of 40% albumin and 60% hemoglobin (weight/weight) was activated by osmotic shrinkage at a dry solid concentration similar to that of intact cells or of ghosts containing only hemoglobin. We conclude that the process of Na/H exchange activation by cell shrinkage originates with an increase in the concentration of intracellular protein and not with a change in membrane configuration or tension. The macromolecular crowding that accompanies the reduction in cell volume probably alters the activities of key enzymes that in turn modulate the Na/H exchanger.

scholarly journals Susceptibility of mouse primary cortical neuronal cells to coxsackievirus B

2004 ◽  
Vol 85 (6) ◽  
pp. 1555-1564 ◽  
Author(s):  
Jeonghyun Ahn ◽  
Jene Choi ◽  
Chul Hyun Joo ◽  
Ilseon Seo ◽  
DongHou Kim ◽  
...  
Keyword(s):  
Morphological Changes ◽  
Chromatin Condensation ◽  
Neuronal Cells ◽  
Virus Production ◽  
Cytopathic Effects ◽  
Transmission Electron ◽  
Coxsackievirus B ◽  
Transcription Inhibitor ◽  
Nuclear Changes ◽  
Induced Apoptosis

Coxsackievirus B (CVB) is often associated with aseptic meningitis and encephalitis, but the six serotypes of CVB vary in their relative disease severity. To elucidate the detailed mechanisms of CVB-induced cytopathological effects, the morphological and biochemical characteristics caused by the CVB serotypes in mouse primary cortical neuronal cells were investigated. By 24 h post-infection, all CVB serotypes except CVB2 induced severe cytotoxic alterations, including a loss of neurites. Both fluorescence and transmission electron microscopy revealed CVB-induced morphological changes indicative of apoptosis, including heavily condensed nuclei, subsequent chromatin condensation into the periphery of the nuclei and oligonucleosomal DNA fragmentation. It was also found that infection with all six CVB serotypes led to productive virus replication, which was completed prior to an apoptotic signal. The caspase inhibitor benzyloxycarbonyl-Val-Ala-Asp-fluoromethyl ketone significantly inhibited nuclear changes associated with virus-induced apoptosis, but had less effect on virus-associated cytopathic effects and no effect on virus production. In contrast, the transcription inhibitor actinomycin D profoundly inhibited all three virus-induced events. Taken together, these findings demonstrate that all six CVB serotypes can efficiently replicate in mouse cortical neuronal cells and that productive replication of these CVBs, except for CVB2, induces multiple cytopathological effects, including apoptotic alterations.

Changes in intracellular electrolyte concentrations during apoptosis induced by UV irradiation of human myeloblastic cells

2006 ◽  
Vol 290 (2) ◽  
pp. C638-C649 ◽  
Author(s):  
F. Arrebola ◽  
E. Fernández-Segura ◽  
A. Campos ◽  
P. V. Crespo ◽  
J. N. Skepper ◽  
...  
Keyword(s):  
Chromatin Condensation ◽  
Cell Shrinkage ◽  
X Ray ◽  
Cell Compartments ◽  
Intracellular Compartments ◽  
Intracellular Concentrations ◽  
Induced Apoptosis ◽  
Key Events ◽  
Intracellular Electrolyte Concentrations ◽  
Active Caspase

Decreases in the intracellular concentrations of both K+ and Cl− have been implicated in playing a major role in the progression of apoptosis, but little is known about the temporal relationship between decreases in electrolyte concentration and the key events in apoptosis, and there is no information about how such decreases affect different intracellular compartments. Electron probe X-ray microanalysis was used to determine changes in element concentrations (Na, P, Cl, and K) in nucleus, cytoplasm, and mitochondria in U937 cells undergoing UV-induced apoptosis. In all compartments, the initial stages of apoptosis were characterized by decreases in [K] and [Cl]. The largest decreases in these elements were in the mitochondria and occurred before the release of cytochrome c. Initial decreases in [K] and [Cl] also preceded apoptotic changes in the nucleus. In the later stages of apoptosis, the [K] continued to decrease, whereas that of Cl began to increase toward control levels and was accompanied by an increase in [Na]. In the nucleus, these increases coincided with poly(ADP-ribose) polymerase cleavage, chromatin condensation, and DNA laddering. The cytoplasm was the compartment least affected and the pattern of change of Cl was similar to those in other compartments, but the decrease in [K] was not significant until after active caspase-3 was detected. Our results support the concept that normotonic cell shrinkage occurs early in apoptosis, and demonstrate that changes in the intracellular concentrations of K and Cl precede apoptotic changes in the cell compartments studied.

Detection and mapping of interactions between chromatin and the nuclear envelope in drosophila embryos

1995 ◽  
Vol 53 ◽  
pp. 764-765
Author(s):  
W.F. Marshall ◽  
A.F. Dernburg ◽  
B. Harmon ◽  
J.W. Sedat
Keyword(s):  
Nuclear Envelope ◽  
Chromatin Condensation ◽  
Three Dimensional ◽  
Physiological Role ◽  
Nuclear Surface ◽  
Intact Cells ◽  
Molecular Determinants ◽  
Surface Harmonic ◽  
Drosophila Embryos

Interactions between chromatin and nuclear envelope (NE) have been implicated in chromatin condensation, gene regulation, nuclear reassembly, and organization of chromosomes within the nucleus. To further investigate the physiological role played by such interactions, it will be necessary to determine which loci specifically interact with the nuclear envelope. This will not only facilitate identification of the molecular determinants of this interaction, but will also allow manipulation of the pattern of chromatin-NE interactions to probe possible functions. We have developed a microscopic approach to detect and map chromatin-NE interactions inside intact cells.Fluorescence in situ hybridization (FISH) is used to localize specific chromosomal regions within the nucleus of Drosophila embryos and anti-lamin immunofluorescence is used to detect the nuclear envelope. Widefield deconvolution microscopy is then used to obtain a three-dimensional image of the sample (Fig. 1). The nuclear surface is represented by a surface-harmonic expansion (Fig 2). A statistical test for association of the FISH spot with the surface is then performed.

Absence of temporal ordering of apoptotic features in heat-shock treated leukemia and lymphoma cell lines

1996 ◽  
Vol 54 ◽  
pp. 758-759
Author(s):  
D. W. Fairbain ◽  
M.D. Standing ◽  
K.L. O'Neill
Keyword(s):  
Heat Shock ◽  
Cell Lines ◽  
Chromatin Condensation ◽  
Membrane Integrity ◽  
Resistant Cell ◽  
Membrane Blebbing ◽  
Late Loss ◽  
Induced Apoptosis ◽  
Dying Cells ◽  
In Cells

Apoptosis is a genetically defined response to physiological stimuli that results in cellular suicide. Features common to apoptotic cells include chromatin condensation, oligonucleosomal DNA fragmentation, membrane blebbing, nuclear destruction, and late loss of ability to exclude vital dyes. These characteristics contrast markedly from pathological necrosis, in which membrane integrity loss is demonstrated early, and other features of apoptosis, which allow a non-inflammatory removal of dead and dying cells, are absent. Using heat shock-induced apoptosis as a model for examining stress response in cells, we undertook to categorize a variety of human leukemias and lymphomas with regard to their response to heat shock. We were also interested in determining whether a common temporal order was followed in cells dying by apoptosis. In addition, based on our previous results, we investigated whether increasing heat load resulted in increased apoptosis, with particular interest in relatively resistant cell lines, or whether the mode of death changed from apoptosis to necrosis.

Cytoplasmic acidification is not an effector mechanism of VP16 or DEX-induced apoptosis in CEM T leukaemia cells

1999 ◽  
Vol 112 (11) ◽  
pp. 1755-1760
Author(s):  
R.S. Benson ◽  
C. Dive ◽  
A.J. Watson
Keyword(s):  
Chromatin Condensation ◽  
Parp Cleavage ◽  
Intracellular Acidification ◽  
Over Expression ◽  
Effector Phase ◽  
Execution Phase ◽  
Cytoplasmic Acidification ◽  
Physiological Values ◽  
Induced Apoptosis

The role of intracellular acidification in the execution phase of apoptosis is not well understood. Here we examine the effect of Bcl-2 over-expression on intracellular acidification occurring during apoptosis. We found, that in CEM cells, neither DEX nor VP16-induced apoptosis lead to a significant change in intracellular pH (pHi). Furthermore, we found that shifting pHi away from physiological values was unable to induce chromatin condensation or poly(ADP-ribose) polymerase (PARP) cleavage in the presence of Bcl-2 over-expression. However, it was found that maximum chromatin condensation and PARP cleavage occurred at near physiological pHi values. Taken together these data suggest that intracellular acidification does not trigger the effector phase of CEM apoptosis.

Regulation of cell function by the cellular hydration state

1994 ◽  
Vol 267 (3) ◽  
pp. E343-E355 ◽  
Author(s):  
D. Haussinger ◽  
F. Lang ◽  
W. Gerok
Keyword(s):  
Cell Volume ◽  
Cell Function ◽  
Narrow Range ◽  
Cell Swelling ◽  
Metabolic Function ◽  
Cell Shrinkage ◽  
Short Term ◽  
Hydration State ◽  
Per Se ◽  
And Oxidative Stress

Cellular hydration can change within minutes under the influence of hormones, nutrients, and oxidative stress. Such short-term modulation of cell volume within a narrow range acts per se as a potent signal which modifies cellular metabolism and gene expression. It appears that cell swelling and cell shrinkage lead to certain opposite patterns of cellular metabolic function. Apparently, hormones and amino acids can trigger those patterns simply by altering cell volume. Thus alterations of cellular hydration may represent another important mechanism for metabolic control and act as another second or third messenger linking cell function to hormonal and environmental alterations.

ACACIA HONEY INDUCES APOPTOSIS IN HUMAN BREAST ADENOCARCINOMA CELL LINES (MCF-7)

2017 ◽  
Vol 79 (4) ◽  
Author(s):  
Muhammad Ashraf Mohd Salleh ◽  
Zolkapli Eshak ◽  
Wan Iryani Wan Ismail
Keyword(s):  
Antioxidant Properties ◽  
Breast Adenocarcinoma ◽  
Total Phenolic ◽  
Flavonoid Content ◽  
Cell Shrinkage ◽  
Cancer Cell Growth ◽  
Breast Cancer Cell Growth ◽  
Acacia Honey ◽  
Induced Apoptosis ◽  
Mcf 7

Apoptosis is one of markers considered in drug design including in treating cancers. Conventional treatments for cancer cause various side effects. One of possible alternatives is honey, an antioxidant driven by its phenolic and flavonoids content. This study aims to observe the effects of Malaysian Acacia honey in inhibiting breast cancer cell growth through apoptosis. Antioxidant properties of the honey were measured using total phenolic content (TPC) and total flavonoid content (TFC). Then, antiproliferative activity of the honey were observed using MTT assay. The honey exhibited IC50 at concentration of 5.5% (v/v). Further studies using TUNEL and live cell view revealed that Acacia honey induced apoptosis after 6 hours of treatment. Cell shrinkage, which is one of the apoptotic features, was observed as early as 2 hours, followed by the formation of apoptotic bodies within 6 hours of the honey treatment. Details of mechanism and actual compounds involved in displaying the results are being intensively studied.

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