scholarly journals Lysosomes and Fas-mediated liver cell death

2007 ◽  
Vol 403 (1) ◽  
pp. 89-95 ◽  
Author(s):  
Robert Wattiaux ◽  
Simone Wattiaux-De Coninck ◽  
Jacqueline Thirion ◽  
Mańe-Christine Gasingirwa ◽  
Michel Jadot
Keyword(s):  
Cell Death ◽  
Cytochrome C ◽  
Caspase 3 ◽  
Ex Vivo ◽  
Jurkat Cells ◽  
Intermembrane Space ◽  
Lysosomal Hydrolases ◽  
Cytochrome C Reductase ◽  
Effector Caspases

A number of studies, mostly performed ex vivo, suggest that lysosomes are involved in apoptosis as a result of a release of their cathepsins into the cytosol. These enzymes could then contribute to the permeabilization of the outer mitochondrial membrane; they could also activate effector caspases. The present study aims at testing whether the membrane of liver lysosomes is disrupted during Fas-mediated cell death of hepatocytes in vivo, a process implicated in several liver pathologies. Apoptosis was induced by injecting mice with aFas (anti-Fas antibody). The state of lysosomes was assessed by determining the proportion of lysosomal enzymes (β-galactosidase, β-glucuronidase, cathepsin C and cathepsin B) present in homogenate supernatants, devoid of intact lysosomes, and by analysing the behaviour in differential and isopycnic centrifugation of β-galactosidase. Apoptosis was monitored by measuring caspase 3 activity (DEVDase) and the release of sulfite cytochrome c reductase, an enzyme located in the mitochondrial intermembrane space. Results show that an injection of 10 μg of aFas causes a rapid and large increase in DEVDase activity and in unsedimentable sulfite cytochrome c reductase. This modifies neither the proportion of unsedimentable lysosomal enzyme in the homogenates nor the behaviour of lysosomes in centrifugation. Experiments performed with a lower dose of aFas (5 μg) indicate that unsedimentable lysosomal hydrolase activity increases in the homogenate after injection but with a marked delay with respect to the increase in DEVDase activity and in unsedimentable sulfite cytochrome c reductase. Comparative experiments ex vivo performed with Jurkat cells show an increase in unsedimentable lysosomal hydrolases, but much later than caspase 3 activation, and a release of dipeptidyl peptidase III and DEVDase into culture medium. It is proposed that the weakening of lysosomes observed after aFas treatment in vivo and ex vivo results from a necrotic process that takes place late after initiation of apoptosis.

scholarly journals Effectiveness of Vitamin C and Vitamin E Antioxidant Combination on Caspase-3 Expression in Wistar White Rat Pulmonum Contusion

2020 ◽  
Vol 3 (1) ◽  
pp. 31-44
Author(s):  
Bermansyah ◽  
Gama Satria ◽  
Ahmad Umar
Keyword(s):  
Cell Death ◽  
Vitamin E ◽  
Vitamin C ◽  
Wistar Rats ◽  
Caspase 3 ◽  
Cell Function ◽  
Pulmonary Contusion ◽  
Tnf Α ◽  
Male Wistar Rats

Introduction.Pulmonary contusions can cause a progressive inflammatory response. Activation of TNF-α cytokines and reactive oxygen species (ROS) can cause pulmonary cell death. Antioxidants can have the potential to neutralize ROS. The purpose of this study is to determine the effectiveness of antioxidant administration in maintaining pulmonary cell function in wistar rats that have been induced to experience pulmonary contusions through caspase-3 levels. Methods.This study was an in vivo experimental study conducted on thirty male wistar rats and divided into five groups (n = 6): control, pulmonary contusion + asthaxanthine 5 mg/kgBW, pulmonary contusion + vitamin C and E 50 mg/kgBW, pulmonary contusion + vitamin C and E 100 mg/kgBW, pulmonary contusion + vitamin C and E 200 mg/kgBW. The value of Caspase-3 is evaluated by the IHC. All data analyzes used SPSS 18. Results. Low doses of antioxidants have the potential to reduce pulmonary cell death in wistar rats induced by pulmonary contusions.Conclussion. Vitamin C and E effective to reduce polmonary cell death in pulmonary contusion.Keywords: antioxidants, vitamin C, vitamin E, pulmonary contusions animal model, apoptosis, caspase-3

scholarly journals APR-246 induces early cell death by ferroptosis in acute myeloid leukemia.

Haematologica ◽  
2021 ◽  
Author(s):  
Rudy Birsen ◽  
Clement Larrue ◽  
Justine Decroocq ◽  
Natacha Johnson ◽  
Nathan Guiraud ◽  
...  
Keyword(s):  
Lipid Peroxidation ◽  
Cell Death ◽  
Acute Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Ex Vivo ◽  
Lipid Peroxides ◽  
Death Process ◽  
Glutathione Biosynthesis ◽  
Acute Myeloid

APR-246 is a promising new therapeutic agent that targets p53 mutated proteins in myelodysplastic syndromes and in acute myeloid leukemia. APR-246 reactivates the transcriptional activity of p53 mutants by facilitating their binding to DNA target sites. Recent studies in solid cancers have found that APR-246 can also induce p53-independent cell death. In this study, we demonstrate that AML cell death occurring early after APR-246 exposure is suppressed by iron chelators, lipophilic antioxidants and inhibitors of lipid peroxidation, and correlates with the accumulation of markers of lipid peroxidation, thus fulfilling the definition of ferroptosis, a recently described cell death process. The capacity of AML cells to detoxify lipid peroxides by increasing their cystine uptake to maintain major antioxidant molecule glutathione biosynthesis after exposure to APR-246 may be a key determinant of sensitivity to this compound. The association of APR-246 with induction of ferroptosis (either by pharmacological compounds, or genetic inactivation of SLC7A11 or GPX4) had a synergistic effect on the promotion of cell death, both in vivo and ex vivo.

scholarly journals Silica nanoparticles inducing the apoptosis of spermatocyte cell through microRNA-450b-3p targeting MTCH2-mediating mitochondrial signaling pathway

2020 ◽  
Author(s):  
Guiqing Zhou ◽  
Jianhui Liu ◽  
Xiangyang Li ◽  
Yujian Sang ◽  
Yue Zhang ◽  
...  
Keyword(s):  
Cytochrome C ◽  
Silica Nanoparticles ◽  
Caspase 3 ◽  
Reproductive Toxicity ◽  
Control Group ◽  
Caspase 9 ◽  
Protein Expressions ◽  
Underlying Mechanisms

Abstract Background: Silica nanoparticles (SiNPs) are found in environmental particulate matter and are proven to have adverse effects on fertility. The relationship and underlying mechanisms between miRNAs and apoptosis induced by SiNPs during spermatogenesis is currently ambiguous. Experimental design: The present study was designed to investigate the role of miRNA-450b-3p in the reproductive toxicity caused by SiNPs. In vivo, 40 male mice were randomly divided into control and SiNPs groups, 20 per group. The mice in the SiNPs group were administrated 20 mg/kg SiNPs by tracheal perfusion once every 5 days, for 35 days, and the control group were given the equivalent of a normal luminal saline. In vitro, spermatocyte cells were divided into 0 and 5 μg/mL SiNPs groups, after passaged for 30 generations, the GC-2spd cells in 5 μg/mL SiNPs groups were transfected with miRNA-450b-3p and its mimic and inhibitor. Results: In vivo, the results showed that SiNPs damaged tissue structures of testis, decreased the quantity and quality of the sperm, reduced the expression of miR-450b-3p, and increased the protein expressions of the MTCH2, BID, BAX, Cytochrome C, Caspase-9, and Caspase-3 in the testis. In vitro, SiNPs obviously repressed the viability and increased the LDH level and apoptosis rate, decreased the levels of the miR-450b-3p, significantly enhanced the protein expressions of the MTCH2, BID, BAX, Cytochrome C, Caspase-9, Caspase-3; while the mimic of miR-450b-3p reversed the changes induced by SiNPs, but inhibitor further promoted the effects induced by SiNPs.Conclusion: The result suggested that SiNPs could induce the spermatocyte apoptosis by inhibiting the miR-450b-3p expression to target promoting the MTCH2 resulting in activating mitochondrial apoptotic signaling pathways in the spermatocyte cells.

Epicatechin and its in vivo metabolite, 3′-O-methyl epicatechin, protect human fibroblasts from oxidative-stress-induced cell death involving caspase-3 activation

2001 ◽  
Vol 354 (3) ◽  
pp. 493-500 ◽  
Author(s):  
Jeremy P. E. SPENCER ◽  
Hagen SCHROETER ◽  
Gunter KUHNLE ◽  
S. Kaila S. SRAI ◽  
Rex M. TYRRELL ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Hydrogen Peroxide ◽  
Cell Death ◽  
Caspase 3 ◽  
Cell Damage ◽  
Protective Action ◽  
Human Fibroblasts ◽  
Membrane Damage ◽  
Antioxidant Properties

There is considerable current interest in the cytoprotective effects of natural antioxidants against oxidative stress. In particular, epicatechin, a major member of the flavanol family of polyphenols with powerful antioxidant properties in vitro, has been investigated to determine its ability to attenuate oxidative-stress-induced cell damage and to understand the mechanism of its protective action. We have induced oxidative stress in cultured human fibroblasts using hydrogen peroxide and examined the cellular responses in the form of mitochondrial function, cell-membrane damage, annexin-V binding and caspase-3 activation. Since one of the major metabolites of epicatechin in vivo is 3′-O-methyl epicatechin, we have compared its protective effects with that of epicatechin. The results provide the first evidence that 3′-O-methyl epicatechin inhibits cell death induced by hydrogen peroxide and that the mechanism involves suppression of caspase-3 activity as a marker for apoptosis. Furthermore, the protection elicited by 3′-O-methyl epicatechin is not significantly different from that of epicatechin, suggesting that hydrogen-donating antioxidant activity is not the primary mechanism of protection.

scholarly journals Overexpression of Ubiquinol-Cytochrome c Reductase Core Protein 1 May Protect H9c2 Cardiac Cells by Binding with Zinc

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Tingting Yi ◽  
Xiaoxiao Wu ◽  
Zonghong Long ◽  
Guangyou Duan ◽  
Zhuoxi Wu ◽  
...  
Keyword(s):  
Cytochrome C ◽  
Caspase 3 ◽  
Direct Evidence ◽  
Core Protein ◽  
Ischemia Reperfusion ◽  
Cardiac Cells ◽  
Protective Effects ◽  
Cytochrome C Reductase ◽  
Simulated Ischemia

In several recent studies, proteomics analyses suggest that increase of ubiquinol-cytochrome c reductase core protein 1 (UQCRC1) is cardio-protective. However, direct evidence for this effect has not yet been obtained. Thus, the current study aimed to determine this effect and the mechanism underlying this effect. The results showed that overexpression of UQCRC1 protected H9c2 cardiac cells against in vitro simulated ischemia-reperfusion by maintaining mitochondrial membrane potential and suppressing the expression of caspase-3. These protective effects were significantly enhanced by exogenous Zn2+ but completely abolished by Zn2+-selective chelator TPEN. Furthermore, the upregulation of UQCRC1 reduced the concentration of free Zn2+ in mitochondria, whereas the downregulation of UQCRC1 increased the concentration of free Zn2+ in mitochondria. In conclusion, the overexpression of UQCRC1 can protect H9c2 cardiac cells against simulated ischemia/reperfusion, and this cardio-protective effect is likely mediated by zinc binding.

scholarly journals Caspase levels and execution efficiencies determine the apoptotic potential of the cell

2012 ◽  
Vol 196 (4) ◽  
pp. 513-527 ◽  
Author(s):  
Anat Florentin ◽  
Eli Arama
Keyword(s):  
Cell Death ◽  
Drosophila Melanogaster ◽  
Activity Levels ◽  
Caspase Activity ◽  
Intrinsic Properties ◽  
Functional Differences ◽  
Effector Caspases ◽  
Set Up

Essentially, all metazoan cells can undergo apoptosis, but some cells are more sensitive than others to apoptotic stimuli. To date, it is unclear what determines the apoptotic potential of the cell. We set up an in vivo system for monitoring and comparing the activity levels of the two main effector caspases in Drosophila melanogaster, Drice and Dcp-1. Both caspases were activated by the apoptosome after irradiation. However, whereas each caspase alone could induce apoptosis, Drice was a more effective inducer of apoptosis than Dcp-1, which instead had a role in establishing the rate of cell death. These functional differences are attributed to their intrinsic properties rather than merely their tissue specificities. Significantly, the levels of the procaspases are directly proportional to their activity levels and play a key role in determining the cell’s sensitivity to apoptosis. Finally, we provide evidence for the existence of a cellular execution threshold of caspase activity, which must be reached to induce apoptosis.

scholarly journals Diablo Promotes Apoptosis by Removing Miha/Xiap from Processed Caspase 9

2001 ◽  
Vol 152 (3) ◽  
pp. 483-490 ◽  
Author(s):  
Paul G. Ekert ◽  
John Silke ◽  
Christine J. Hawkins ◽  
Anne M. Verhagen ◽  
David L. Vaux
Keyword(s):  
Cell Death ◽  
Cytochrome C ◽  
Caspase 3 ◽  
Direct Interaction ◽  
Inhibitor Of Apoptosis ◽  
Caspase 9 ◽  
Inhibitor Of Apoptosis Protein ◽  
Grim Reaper ◽  
Apoptosis Protein ◽  
Mammalian Protein

MIHA is an inhibitor of apoptosis protein (IAP) that can inhibit cell death by direct interaction with caspases, the effector proteases of apoptosis. DIABLO is a mammalian protein that can bind to IAPs and antagonize their antiapoptotic effect, a function analogous to that of the proapoptotic Drosophila molecules, Grim, Reaper, and HID. Here, we show that after UV radiation, MIHA prevented apoptosis by inhibiting caspase 9 and caspase 3 activation. Unlike Bcl-2, MIHA functioned after release of cytochrome c and DIABLO from the mitochondria and was able to bind to both processed caspase 9 and processed caspase 3 to prevent feedback activation of their zymogen forms. Once released into the cytosol, DIABLO bound to MIHA and disrupted its association with processed caspase 9, thereby allowing caspase 9 to activate caspase 3, resulting in apoptosis.

scholarly journals Bcl-2 overexpression in type II epithelial cells does not prevent hyperoxia-induced acute lung injury in mice

2010 ◽  
Vol 299 (3) ◽  
pp. L312-L322 ◽  
Author(s):  
Isabelle Métrailler-Ruchonnet ◽  
Alessandra Pagano ◽  
Stéphanie Carnesecchi ◽  
Karim Khatib ◽  
Pedro Herrera ◽  
...  
Keyword(s):  
Cell Death ◽  
Epithelial Cells ◽  
Lung Injury ◽  
Ex Vivo ◽  
Lung Damage ◽  
Type Ii Cells ◽  
Type Ii ◽  
Lung Weight

Bcl-2 is an anti-apoptotic molecule preventing oxidative stress damage and cell death. We have previously shown that Bcl-2 is able to prevent hyperoxia-induced cell death when overexpressed in a murine fibrosarcoma cell line L929. We hypothesized that its specific overexpression in pulmonary epithelial type II cells could prevent hyperoxia-induced lung injury by protecting the epithelial side of the alveolo-capillary barrier. In the present work, we first showed that in vitro Bcl-2 can rescue murine pulmonary epithelial cells (MLE12) from oxygen-induced cell apoptosis, as shown by analysis of LDH release, annexin V/propidium staining, and caspase-3 activity. We then generated transgenic mice overexpressing specifically Bcl-2 in lung epithelial type II cells under surfactant protein C (SP-C) promoter (Tg-Bcl-2) and exposed them to hyperoxia. Bcl-2 did not hinder hyperoxia-induced mitochondria and DNA oxidative damage of type II cell in vivo. Accordingly, lung damage was identical in both Tg-Bcl-2 and littermate mice strains, as measured by lung weight, bronchoalveolar lavage, and protein content. Nevertheless, we observed a significant lower number of TUNEL-positive cells in type II cells isolated from Tg-Bcl-2 mice exposed to hyperoxia compared with cells isolated from littermate mice. In summary, these results show that although Bcl-2 overexpression is able to prevent hyperoxia-induced cell death at single cell level in vitro and ex vivo, it is not sufficient to prevent cell death of parenchymal cells and to protect the lung from acute damage in mice.

The AKT Inhibitor, A443654, Induces Cell Cycle Arrest, Apoptosis and Synergizes with Chemotherapeutic Drugs in Multi-Drug Resistant T-Cell Acute Lymphoblastic Leukemia - A Novel Agent for Therapy of Drug Resistant ALL.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 3344-3344
Author(s):  
James A. McCubrey ◽  
William L. Blalock ◽  
Pier Luigi Tazzari ◽  
Alessandra Cappellini ◽  
Ilaria Iacobucci ◽  
...  
Keyword(s):  
Cell Death ◽  
Caspase 3 ◽  
Apoptotic Cell ◽  
Apoptotic Cell Death ◽  
Jurkat Cells ◽  
Drug Resistant ◽  
Akt Inhibitor ◽  
Cycle Arrest ◽  
Hematopoietic Precursor ◽  
Dose Dependent

Abstract The PI3K/Akt pathway is a key mediator of proliferation and survival; its constitutive activation is implicated in pathogenesis and progression of a wide variety of hematological malignancies. Constitutively-activated Akt is a common feature of the T-ALL cell lines (MOLT-4, Jurkat, CEM). Hyperactivity of Akt leads not only to their growth and resistance to apoptosis but also to drug-resistance. In this study, we sought to examine the potential of a novel Akt inhibitor, A443654, in the therapy of T-ALL. A443654 led to rapid cell death of CEM, Jurkat, and MOLT-4. All three lines were sensitive to nanomolar (nM) doses of A443654 (IC50=60 nM, 120 nM and 900 nM for MOLT-4, CEM, and Jurkat, respectively). Effects were dose dependent and resulted in G2/M arrest. Indeed, approximately 39% of Jurkat cells treated with A443654 were in G2/M whereas only 11% of the untreated cells were in G2/M. Cell cycle arrest was followed by apoptotic cell death as determined by annexin V-PI and trypan blue staining. Treatment of CEM and Jurkat cells led to de-phosphorylation of the downstream Akt substrate GSK-3beta. Treatment of Jurkat cells with A443654 resulted in activation of caspase-2, -3, -8, and -9. Apoptotic cell death was greatly reduced by caspase-3 and -9 selective inhibitors. Additionally, A443654 was shown to be highly effective against the drug-resistant cell line CEM-VBL100 (CEM-R), which overexpresses Pgp. This Akt inhibitor initially (1 to 4 hour treatments) decreased Pgp activity, but not protein levels, further documenting a link between Akt and Pgp activity. While CEM-R cells displayed decreased sensitivity to A443654, treatment of CEM-R cells with sub-lethal doses of A443654 for 24 hours, reduced the surface expression of Pgp. Moreover, A443654 synergized with the DNA damaging agent etoposide, a substrate of Ppg, in both drug sensitive and resistant lines. At etoposide concentrations between 25 mM to 100 mM, A443654 enhanced the extent of cell killing from 25% to 45%. We then confirmed the effect of A443654 on human leukemia samples using blasts from 6 patients with T-ALL, all of whom displayed constitutive Akt activation. In a dose dependent fashion, A443654 was able to induce apoptotic cell death of T-ALL blast cells, as indicated by flow cytometric analysis of samples immunostained for active (cleaved) caspase-3. In contrast, this Akt inhibitor was determined to be minimally cytotoxic on normal CD34+ hematopoietic precursor cells isolated from cord blood. Taken together, our findings indicate that the Akt inhibitor, A443654, either alone or in combination with existing drugs, may in the future be a useful therapeutic option for primary and refractory T-ALL displaying activated Akt signaling. Furthermore, this novel Akt inhibitor was effective in suppressing the growth of multidrug resistant ALL cells while having minimal effects on normal hematopoietic precursor cells documenting its poteintial in the treatment of drug resistant leukemias.

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