Cell Injury, Cellular Responses to Injury, and Cell Death

Author(s):  
Thomas C. King
Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1521
Author(s):  
Micael Rodrigues Cunha ◽  
Maurício Temotheo Tavares ◽  
Thais Batista Fernandes ◽  
Roberto Parise-Filho

Piper, Capsicum, and Pimenta are the main genera of peppers consumed worldwide. The traditional use of peppers by either ancient civilizations or modern societies has raised interest in their biological applications, including cytotoxic and antiproliferative effects. Cellular responses upon treatment with isolated pepper-derived compounds involve mechanisms of cell death, especially through proapoptotic stimuli in tumorigenic cells. In this review, we highlight naturally occurring secondary metabolites of peppers with cytotoxic effects on cancer cell lines. Available mechanisms of cell death, as well as the development of analogues, are also discussed.


2021 ◽  
Vol 22 (1) ◽  
pp. 412
Author(s):  
Christopher L. Moore ◽  
Alena V. Savenka ◽  
Alexei G. Basnakian

Terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay is a long-established assay used to detect cell death-associated DNA fragmentation (3’-OH DNA termini) by endonucleases. Because these enzymes are particularly active in the kidney, TUNEL is widely used to identify and quantify DNA fragmentation and cell death in cultured kidney cells and animal and human kidneys resulting from toxic or hypoxic injury. The early characterization of TUNEL as an apoptotic assay has led to numerous misinterpretations of the mechanisms of kidney cell injury. Nevertheless, TUNEL is becoming increasingly popular for kidney injury assessment because it can be used universally in cultured and tissue cells and for all mechanisms of cell death. Furthermore, it is sensitive, accurate, quantitative, easily linked to particular cells or tissue compartments, and can be combined with immunohistochemistry to allow reliable identification of cell types or likely mechanisms of cell death. Traditionally, TUNEL analysis has been limited to the presence or absence of a TUNEL signal. However, additional information on the mechanism of cell death can be obtained from the analysis of TUNEL patterns.


1999 ◽  
Vol 340 (1) ◽  
pp. 291-297 ◽  
Author(s):  
Matthäus M. RIMPLER ◽  
Ursula RAUEN ◽  
Thorsten SCHMIDT ◽  
Tarik MÖRÖY ◽  
Herbert DE GROOT

The oncoprotein Bcl-2 protects cells against apoptosis, but the exact molecular mechanism that underlies this function has not yet been identified. Studying H2O2-induced cell injury in Rat-1 fibroblast cells, we observed that Bcl-2 had a protective effect against the increase in cytosolic calcium concentration and subsequent cell death. Furthermore, overexpression of Bcl-2 resulted in an alteration of cellular glutathione status: the total amount of cellular glutathione was increased by about 60% and the redox potential of the cellular glutathione pool was maintained in a more reduced state during H2O2 exposure compared with non-Bcl-2-expressing controls. In our cytotoxicity model, disruption of cellular glutathione homoeostasis closely correlated with the pathological elevation of cytosolic calcium concentration. Stabilization of the glutathione pool by Bcl-2, N-acetylcysteine or glucose delayed the cytosolic calcium increase and subsequent cell death, whereas depletion of glutathione by DL-buthionine-(S,R)-sulphoximine, sensitized Bcl-2-transfected cells towards cytosolic calcium increase and cell death. We therefore suggest that the protection exerted by Bcl-2 against H2O2-induced cytosolic calcium elevation and subsequent cell death is secondary to its effect on the cellular glutathione metabolism.


2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Abhishek A. Kulkarni ◽  
Abass M. Conteh ◽  
Cody A. Sorrell ◽  
Anjali Mirmira ◽  
Sarah A. Tersey ◽  
...  

It is well known that a chronic state of elevated reactive oxygen species (ROS) in pancreaticβ-cells impairs their ability to release insulin in response to elevated plasma glucose. Moreover, at its extreme, unmitigated ROS drives regulated cell death. This dysfunctional state of ROS buildup can result both from genetic predisposition and environmental factors such as obesity and overnutrition. Importantly, excessive ROS buildup may underlie metabolic pathologies such as type 2 diabetes mellitus. The ability to monitor ROS dynamics inβ-cells in situ and to manipulate it via genetic, pharmacological, and environmental means would accelerate the development of novel therapeutics that could abate this pathology. Currently, there is a lack of models with these attributes that are available to the field. In this study, we use a zebrafish model to demonstrate that ROS can be generated in aβ-cell-specific manner using a hybrid chemical genetic approach. Using a transgenic nitroreductase-expressing zebrafish line,Tg(ins:Flag-NTR)s950, treated with the prodrug metronidazole (MTZ), we found that ROS is rapidly and explicitly generated inβ-cells. Furthermore, the level of ROS generated was proportional to the dosage of prodrug added to the system. At high doses of MTZ, caspase 3 was rapidly cleaved,β-cells underwent regulated cell death, and macrophages were recruited to the islet to phagocytose the debris. Based on our findings, we propose a model for the mechanism of NTR/MTZ action in transgenic eukaryotic cells and demonstrate the robust utility of this system to model ROS-related disease pathology.


1996 ◽  
Vol 270 (4) ◽  
pp. H1334-H1341 ◽  
Author(s):  
T. L. Vanden Hoek ◽  
Z. Shao ◽  
C. Li ◽  
R. Zak ◽  
P. T. Schumacker ◽  
...  

The extent of cardiac injury incurred during reperfusion as opposed to that occurring during ischemia is unclear. This study tested the hypothesis that simulated ischemia followed by simulated reperfusion causes significant "reperfusion injury" in isolated chick cardiomyocytes. Cells were exposed to hypoxia, hypercarbic acidosis, hyperkalemia, and substrate deprivation for 1 h followed by 3 h of reperfusion. Irreversible cell membrane injury, measured by propidium iodide uptake, increased from 4% of cells at the end of ischemia to 73% after reperfusion; death occurred in only 17% of cells kept ischemic for 4 h. Lactate dehydrogenase release was consistent with these changes. Lengthening ischemia from 30 to 90 min increased cell injury as expected, but of the total cell death, > 90% occurred during reperfusion. "Chemical hypoxia" composed of cyanide (2.5 mM) plus 2-deoxyglucose augmented injury before reperfusion compared with simulated ischemia. Inhibition of oxygen radical generation by use of metal chelator 1,10-phenanthroline reduced cell death from 73% to 40% after reperfusion (P = 0.001). We conclude that simulated reperfusion significantly augments the cellular membrane damage elicited by simulated ischemia in isolated cardiomyocytes devoid of other factors and suggest that reactive oxygen species, perhaps from the mitochondria, participate in this injury.


1994 ◽  
Vol 267 (1) ◽  
pp. C67-C74 ◽  
Author(s):  
A. L. Nieminen ◽  
A. K. Saylor ◽  
B. Herman ◽  
J. J. Lemasters

The importance of ATP depletion and mitochondrial depolarization in the toxicity of cyanide, oligomycin, and carbonyl cyanide m-cholorophenylhydrazone (CCCP), an uncoupler, was evaluated in rat hepatocytes. Oligomycin, an inhibitor of the reversible mitochondrial ATP synthase (F1F0-adenosinetriphosphatase), caused dose-dependent cell killing with 0.1 microgram/ml being the minimum concentration causing the maximum cell killing. Oligomycin also caused rapid ATP depletion without causing mitochondrial depolarization. Fructose (20 mM), a potent glycolytic substrate in liver, protected completely against oligomycin toxicity. CCCP (5 microM) also caused rapid killing of hepatocytes. Fructose retarded cell death caused by CCCP but failed to prevent lethal cell injury. Although oligomycin (1.0 microgram/ml) was lethally toxic by itself, in the presence of fructose it protected completely against CCCP-induced cell killing. Cyanide (2.5 mM), an inhibitor of mitochondrial respiration, caused rapid cell killing that was reversed by fructose. CCCP completely blocked fructose protection against cyanide, causing mitochondrial depolarization and rapid ATP depletion. In the presence of fructose and cyanide, oligomycin protected cells against CCCP-induced ATP depletion and cell death but did not prevent mitochondrial depolarization. In every instance, cell killing was associated with ATP depletion, whereas protection against lethal cell injury was associated with preservation of ATP. In conclusion, protection by fructose against toxicity of cyanide, oligomycin, and CCCP was mediated by glycolytic ATP formation rather than by preservation of the mitochondrial membrane potential. These findings support the hypothesis that inhibition of cellular ATP formation is a crucial event in the progression of irreversible cell injury.


2011 ◽  
pp. 1-11
Author(s):  
Adone Baroni ◽  
Eleonora Ruocco ◽  
Maria Antonietta Tufano ◽  
Elisabetta Buommino
Keyword(s):  

1995 ◽  
Vol 269 (2) ◽  
pp. G287-G296 ◽  
Author(s):  
A. J. Dziki ◽  
S. Batzri ◽  
J. W. Harmon ◽  
M. Molloy

Ca2+ entry into the cell may be an early event in the pathophysiology of bile salt-induced gastric mucosal injury. The aim of this study was to characterize the rise in cytosolic free Ca2+ associated with bile salt injury and its association with cell injury and death. Rabbit gastric mucosal cells were preloaded with the Ca2+ indicator fura 2-acetoxymethyl ester (fura 2-AM) for 20 min at 37 degrees C and then exposed to graded concentrations of the bile salt deoxycholate (DC). Cytosolic free Ca2+ concentration ([Ca2+]i) was estimated by spectrofluorometry. The resting [Ca2+]i in gastric cells was 177 +/- 15 nM (n = 6). When cells were subjected to 0.5 mM DC, there was a time-dependent rise in [Ca2+]i. An increase in [Ca2+]i was observed within 2 min, at which time [Ca2+]i rose from 177 +/- 15 to 480 +/- 30 nM. The maximal increase in [Ca2+]i was observed after 20 min of exposure to 0.5 mM DC (639 +/- 49 nM), and [Ca2+]i remained unchanged for at least 2 h. The increase in [Ca2+]i depended on the concentration of DC. The minimum effective dose of DC was 0.2 mM, with which [Ca2+]i was increased by 1.6-fold (from 177 to 285 nM). At 0.5 mM DC also caused a rise in 45Ca2+ influx into the cells and reduced the viability of gastric cells from 96% to 58% at 2 h. The DC-induced rise in cytosolic free Ca2+ depended on the presence of extracellular Ca2+. In the absence of extracellular Ca2+ there was no rise in cytosolic Ca2+ and gastric cells were protected from cell death caused by DC. The DC-induced cell death was reduced from 26% to 10% and from 37% to 16% at 60 and 90 min, respectively, by removal of extracellular Ca2+. The association of DC with gastric cells was not altered by removing extracellular Ca2+. This suggests decreased DC-induced injury in the absence of extracellular Ca2+ is due to the protection from cellular hypercalcemia rather than some other mechanism related to reduced binding and/or association of DC to gastric cells. These experiments show that rising [Ca2+]i appears to be an early pathophysiological event in bile salt-induced cellular injury and that extracellular Ca2+ is critical to produce this effect.


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