Acellular hemoglobin-mediated oxidative stress toward endothelium: a role for ferryl iron

1998 ◽  
Vol 275 (3) ◽  
pp. H1046-H1053 ◽  
Author(s):  
Daniel W. Goldman ◽  
Richard J. Breyer ◽  
David Yeh ◽  
Beth A. Brockner-Ryan ◽  
Abdu I. Alayash
Keyword(s):  
Hydrogen Peroxide ◽  
Endothelial Cells ◽  
Cell Death ◽  
Dna Fragmentation ◽  
Apoptotic Cell ◽  
Morphological Changes ◽  
Blood Substitutes ◽  
Apoptotic Cell Death ◽  
Redox Activity ◽  
Chemically Modified

We tested the hypothesis that chemical modifications used to produce stable, oxygen-carrying, Hb-based blood substitutes can induce cytotoxicity in endothelial cells in culture because of altered redox activity. We examined the interaction of hydrogen peroxide with nonmodified hemoglobin (HbA0) and two chemically modified hemoglobins, α-cross-linked hemoglobin (α-DBBF) and its polymerized form (poly-α-DBBF). Hydrogen peroxide-induced cell death (as assessed by lactate dehydrogenase release) in bovine aortic endothelial cells (BAEC) was completely inhibited by all three hemoglobin preparations, consistent with their known pseudoperoxidase activity [hemoglobin consumes peroxide as it cycles between ferric (Fe3+) and ferryl (Fe4+) hemes]. However, reaction of the modified hemoglobins, but not HbA0, with hydrogen peroxide induced apoptotic cell death (as assessed by morphological changes and DNA fragmentation) that correlated with the formation of a long-lived ferrylhemoglobin. A preparation of ferryl-α-DBBF free of residual peroxide rapidly induced morphological changes and DNA fragmentation in BAEC, indicative of apoptotic cell death. Redox cycling of chemically modified hemoglobins by peroxide yielded a persistent ferryl iron that was cytotoxic to endothelial cells.

Induction of Apoptotic Cell Death in Vascular Endothelial Cells Cultured in Three-Dimensional Collagen Lattice

1999 ◽  
Vol 248 (2) ◽  
pp. 498-508 ◽  
Author(s):  
Masafumi Kuzuya ◽  
Shosuke Satake ◽  
Miguel A. Ramos ◽  
Shigeru Kanda ◽  
Teruhiko Koike ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Cell Death ◽  
Vascular Endothelial Cells ◽  
Apoptotic Cell ◽  
Three Dimensional ◽  
Apoptotic Cell Death ◽  
Vascular Endothelial ◽  
Collagen Lattice ◽  
Cells Cultured

Bufalin Induces Apoptotic Cell Death in Human Nasopharyngeal Carcinoma Cells through Mitochondrial ROS and TRAIL Pathways

2019 ◽  
Vol 47 (01) ◽  
pp. 237-257 ◽  
Author(s):  
En-Yun Su ◽  
Yung-Lin Chu ◽  
Fu-Shin Chueh ◽  
Yi-Shih Ma ◽  
Shu-Fen Peng ◽  
...  
Keyword(s):  
Cell Death ◽  
Nasopharyngeal Carcinoma ◽  
Er Stress ◽  
Apoptotic Cell ◽  
Morphological Changes ◽  
Chromatin Condensation ◽  
Apoptotic Cell Death ◽  
Dapi Staining ◽  
Human Nasopharyngeal Carcinoma ◽  
Associated Proteins

The aim of this study was to investigate the effects of bufalin on human nasopharyngeal carcinoma NPC-TW 076 cells in vitro. Bufalin is a cardiotonic steroid and a key active ingredient of the Chinese medicine ChanSu. The extracts of Chansu are used for various cancer treatments in China. In the present study, bufalin induced cell morphological changes, decreased total cell viability and induced G2/M phase arrest of cell cycle in NPC-TW 076 cells. Results also indicated that bufalin induced chromatin condensation (cell apoptosis) and DNA damage by DAPI staining and comet assay, respectively. The induced apoptotic cell death was further confirmed by annexin-V/PI staining assay. In addition, bufalin also increased ROS and Ca[Formula: see text] production and decreased the levels of [Formula: see text]. Furthermore, the alterations of ROS, ER stress and apoptosis associated protein expressions were investigated by Western blotting. Results demonstrated that bufalin increased the expressions of ROS associated proteins, including SOD (Cu/Zn), SOD2 (Mn) and GST but decreased that of catalase. Bufalin increased ER stress associated proteins (GRP78, IRE-1[Formula: see text], IRE-1[Formula: see text], caspase-4, ATF-6[Formula: see text], Calpain 1, and GADD153). Bufalin increased the pro-apoptotic proteins Bax, and apoptotic associated proteins (cytochrome c, caspase-3, -8 and -9, AIF and Endo G) but reduced anti-apoptotic protein Bcl-2 in NPC-TW 076 cells. Furthermore, bufalin elevated the expressions of TRAIL-pathway associated proteins (TRAIL, DR4, DR5, and FADD). Based on these findings, we suggest bufalin induced apoptotic cell death via caspase-dependent, mitochondria-dependent and TRAIL pathways in human nasopharyngeal carcinoma NPC-TW 076 cells.

scholarly journals Distinct downstream signaling and the roles of VEGF and PlGF in high glucose-mediated injuries of human retinal endothelial cells in culture

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Wanzhen Jiao ◽  
Jia-Fu Ji ◽  
Wenwen Xu ◽  
Wenjuan Bu ◽  
Yuanjie Zheng ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Cell Death ◽  
Growth Factor ◽  
High Glucose ◽  
Apoptotic Cell ◽  
Apoptotic Cell Death ◽  
Blood Retinal Barrier ◽  
Western Blots ◽  
Retinal Endothelial Cells ◽  
Protein Levels

Abstract Vascular endothelial growth factor (VEGF) and placental growth factor (PlGF) plays a crucial role in breakdown of the blood-retinal barrier due to hyperpermeability in diabetic retinopathy (DR). However, the distinct signaling driven by VEGF and PlGF in the pathogenesis of DR remains unclear. In this study, we investigated VEGF- and PlGF- related signaling pathways and their roles in cultured human microvascular retinal endothelial cells (hRECs) under high glucose conditions (HG; 25 mM). Apoptotic cell death was evaluated, and FITC conjugated bovine serum albumin across monolayer hRECs served as an index of permeability. Western blots were used to assess the protein levels of VEGF and PlGF, as well as the phosphorylation of p38MAPK, STAT1 and Erk1/2. Knockdown of VEGF and PlGF was performed by using siRNA. Following HG treatment, increases of VEGF and PlGF as well as PKC activity were detected in hRECs. Increased phosphorylations of p38MAPKThr180/Thr182, STAT1Ser727, and Erk1/2Tyr202/Tyr185 as well as VEGFR1Tyr1213 and VEGFR2Tyr1175 were also detected in HG-treated hRECs. Inhibition of PKC activity by Go 6976 prevented HG-induced increases of phosphor-Erk1/2 and nitric oxide synthase (NOS1) expressions as well as hyperpermeability, whereas inhibition of p38MAPK pathway by SB203580 selectively suppressed activation of STAT1 and decreased apoptotic cell death under HG conditions. Moreover, VEGF knockdown predominantly inhibited activation of VEGFR2, and phosphorylation of p38MAPK and STAT1, as well as apoptotic cell death in HG-treated hRECs. Nevertheless, PlGF knockdown mainly suppressed phosphorylation of VEGFR1, PKC, and Erk1/2, as well as NOS1 expressions and hyperpermeability. Taken together, we provide evidence demonstrating that HG-induced elevation of PlGF is responsible for hyperpermeability mainly through increasing activation of PKC-Erk1/2-NOS axis via VEGFR1, while HG-induced elevation of VEGF is associated with induction of apoptotic cell death mainly through increasing activation of p38MAPK/STAT1 signaling via VEGFR2.

Redistribution of phosphatidylethanolamine and phosphatidylserine precedes reperfusion-induced apoptosis

1998 ◽  
Vol 274 (1) ◽  
pp. H242-H248 ◽  
Author(s):  
Nilanjana Maulik ◽  
Valerian E. Kagan ◽  
Vladimir A. Tyurin ◽  
Dipak K. Das
Keyword(s):  
Cell Death ◽  
Dna Fragmentation ◽  
Genomic Dna ◽  
High Performance ◽  
Apoptotic Cell ◽  
Ischemia Reperfusion ◽  
Apoptotic Cell Death ◽  
Dna Laddering ◽  
Outer Leaflet ◽  
Induced Apoptosis

Although cardiomyocyte death and infarction associated with ischemia-reperfusion are traditionally believed to be induced via necrosis, recent studies implicated apoptotic cell death in ischemic reperfused tissue. To examine whether myocardial ischemic reperfusion injury is mediated by apoptotic cell death, isolated perfused rat hearts were subjected to 15 and 30 min of ischemia as well as 15 min of ischemia followed by 30, 90, or 120 min of reperfusion. At the end of each experiment, hearts were processed for the evaluation of apoptosis and DNA laddering. Apoptosis was studied by visualizing the apoptotic cardiomyocytes by direct fluorescence detection of digoxigenin-labeled genomic DNA using APOPTAG in situ apoptosis detection kit. DNA laddering was evaluated by subjecting the DNA obtained from cardiomyocytes to 1.8% agarose gel electrophoresis and photographed under ultraviolet illumination. In addition, high-performance thin-layer chromatography (HPTLC) of aminophospholipids labeled with 2,4,6-trinitrobenzenesulfonate was performed to evaluate phospholipid topography in cardiomyocytes. The results of our study revealed apoptotic cells only in the 90- and 120-min reperfused hearts as demonstrated by the intense fluorescence of the immunostained digoxigenin-labeled genomic DNA when observed under fluorescence microscope. None of the ischemic hearts showed any evidence of apoptosis. These results corroborated with the findings of DNA fragmentation that showed increased ladders of DNA bands in the 120-min reperfused hearts, representing integer multiples of the internucleosomal DNA length (∼180 bp). Two-dimensional HPTLC of the phospholipids obtained from the cardiomyocytes and transbilayer organization of the phosphatidylethanolamine (PE) and phosphatidylserine (PS) in the myocytes indicated translocation of both PE and PS from the inner leaflet to the outer leaflet of the membrane as early as after 20 min of ischemia. These results demonstrate that the redistribution of PS and PE precedes the apototic cell death and DNA fragmentation associated with the reperfusion of ischemic myocardium, suggesting that ischemia may trigger the signal for apoptosis although it becomes evident during reperfusion.

Mitochondrial pathway is involved in hydrogen-peroxide-induced apoptotic cell death of oligodendrocytes

Glia ◽  
2004 ◽  
Vol 46 (4) ◽  
pp. 446-455 ◽  
Author(s):  
Thomas Mronga ◽  
Thomas Stahnke ◽  
Olaf Goldbaum ◽  
Christiane Richter-Landsberg
Keyword(s):  
Hydrogen Peroxide ◽  
Cell Death ◽  
Apoptotic Cell ◽  
Mitochondrial Pathway ◽  
Apoptotic Cell Death

Failure of gelsolin overexpression to regulate lymphocyte apoptosis

Blood ◽  
2000 ◽  
Vol 95 (11) ◽  
pp. 3483-3488 ◽  
Author(s):  
S. Celeste Posey ◽  
Maria Paola Martelli ◽  
Toshifumi Azuma ◽  
David J. Kwiatkowski ◽  
Barbara E. Bierer
Keyword(s):  
Cell Death ◽  
Growth Factor ◽  
Actin Filaments ◽  
Caspase 3 ◽  
Apoptotic Cell ◽  
Morphological Changes ◽  
Apoptotic Cell Death ◽  
Model Systems ◽  
Dependent Manner ◽  
Amino Terminal

Abstract The actin regulatory protein gelsolin cleaves actin filaments in a calcium- and polyphosphoinositide-dependent manner. Gelsolin has recently been described as a novel substrate of the cysteinyl protease caspase-3, an effector protease activated during apoptosis. Cleavage by caspase-3 generates an amino-terminal fragment of gelsolin that can sever actin filaments independently of calcium regulation. The disruption of the actin cytoskeleton by cleaved gelsolin is hypothesized to mediate many of the downstream morphological changes associated with apoptosis. In contrast, overexpression of full-length gelsolin has also been reported to inhibit apoptotic cell death upstream of the activation of caspase-3, suggesting that gelsolin may also act prior to commitment to cell death. The authors previously observed that actin stabilization by the cell permeant agent jasplakinolide enhanced cell death upon interleukin (IL)-2 or IL-3 withdrawal from growth-factor–dependent lymphocyte cell lines, and hypothesized that actin polymerization could alter the activity of gelsolin, thus enhancing apoptosis. Here the authors show that constitutive overexpression of gelsolin did not, however, inhibit or dramatically enhance apoptotic cell death upon growth-factor withdrawal, nor did it modify sensitivity to jasplakinolide. In contrast to previous reports, overexpression of gelsolin in Jurkat T cells did not prevent or delay apoptosis induced by Fas ligation or ceramide treatment. Overexpressed gelsolin protein was cleaved during apoptosis, as seen previously in this and other cell types. In these model systems, therefore, the level of gelsolin expression was not a rate-limiting determinant in commitment to or time to the morphological changes of apoptosis.

Functional Validation of DownRegulated MicroRNAs in HeLa Cells Treated with Polyalthia longifolia Leaf Extract Using Different Microscopic Approaches: A Morphological Alteration-Based Validation

2019 ◽  
Vol 25 (05) ◽  
pp. 1263-1272 ◽  
Author(s):  
Shanmugapriya ◽  
Soundararajan Vijayarathna ◽  
Sreenivasan Sasidharan
Keyword(s):  
Cell Death ◽  
Electron Microscope ◽  
Hela Cells ◽  
Leaf Extract ◽  
Apoptotic Cell ◽  
Morphological Changes ◽  
Apoptotic Cell Death ◽  
Morphological Alteration ◽  
Polyalthia Longifolia

AbstractSeveral microscopy methods have been developed to assess the morphological changes in cells in the investigations of the mode of cell death in response to a stimulus. Our recent finding on the treatment of the IC50 concentration (26.67 μg/mL) of Polyalthia longifolia leaf extract indicated the induction of apoptotic cell death via the regulation of miRNA in HeLa cells. Hence, the current study was conducted to validate the function of these downregulated microRNAs in P. longifolia-treated HeLa cells using microscopic approaches. These include scanning electron microscope (SEM), transmission electron microscope (TEM), and acridine orange/propidium iodide (AO/PI)-based fluorescent microscopy techniques by observing the morphological alterations to cells after transfection with mimic miRNA. Interestingly, the morphological changes observed in this study demonstrated the apoptotic hallmarks, for instance, cell blebbing, cell shrinkage, cytoplasmic and nuclear condensation, vacuolization, cytoplasmic extrusion, and the formation of apoptotic bodies, which proved the role of dysregulated miRNAs in apoptotic HeLa cell death after treatment with the P. longifolia leaf extract. Conclusively, the current study proved the crucial role of downregulated miR-484 and miR-221-5p in the induction of apoptotic cell death in P. longifolia-treated HeLa cells using three approaches—SEM, TEM, and AO/PI-based fluorescent microscope.

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