miR-98 protects endothelial cells against hypoxia/reoxygenation induced-apoptosis by targeting caspase-3

2015 ◽  
Vol 467 (3) ◽  
pp. 595-601 ◽  
Author(s):  
He-wen Li ◽  
Yan Meng ◽  
Qun Xie ◽  
Wen-jing Yi ◽  
Xue-li Lai ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Caspase 3 ◽  
Induced Apoptosis ◽  
Hypoxia Reoxygenation

Downregulation of Dicer expression by serum withdrawal sensitizes human endothelial cells to apoptosis

2008 ◽  
Vol 295 (6) ◽  
pp. H2512-H2521 ◽  
Author(s):  
Satoshi Asada ◽  
Tomosaburo Takahashi ◽  
Koji Isodono ◽  
Atsuo Adachi ◽  
Hiroko Imoto ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Caspase 3 ◽  
Umbilical Vein ◽  
Vascular Endothelial Cell ◽  
Serum Withdrawal ◽  
Tyrosine Kinase 2 ◽  
Nitric Oxide Synthase 3 ◽  
Induced Apoptosis ◽  
Dicer Expression ◽  
Umbilical Vein Endothelial Cells

Although the modulated expression of Dicer is documented upon neoplastic transformation, little is known of the regulation of Dicer expression by environmental stimuli and its roles in the regulation of cellular functions in primary cells. In this study, we found that Dicer expression was downregulated upon serum withdrawal in human umbilical vein endothelial cells (HUVECs). Serum withdrawal induced a time-dependent repression of Dicer expression, which was specifically rescued by vascular endothelial cell growth factor or sphingosine-1-phosphate. When Dicer expression was silenced by short-hairpin RNA against Dicer, the cells were more prone to apoptosis under serum withdrawal, whereas the rate of apoptosis was comparable with control cells in the serum-containing condition. Real-time PCR-based gene expression profiling identified several genes, the expression of which was modulated by Dicer silencing, including adhesion and matrix-related molecules, caspase-3, and nitric oxide synthase 3 (NOS3). Dicer silencing markedly impaired migratory functions without affecting cell adhesion and repressed phosphorylation of focal adhesion kinase and proline-rich tyrosine kinase 2 in adherent HUVECs. Dicer knockdown upregulated caspase-3 and downregulated NOS3 expression, and serum withdrawal indeed increased caspase-3 and decreased NOS3 expression. Furthermore, the overexpression of Dicer in HUVECs resulted in a marked reduction in apoptosis upon serum withdrawal and a decreased caspase-3 and increased NOS3 expression. The inhibition of NOS activity by Nω-nitro-l-arginine methyl ester abrogated the effect of Dicer overexpression to rescue the cells from serum withdrawal-induced apoptosis. These results indicated that serum withdrawal decreases Dicer expression, leading to an increased susceptibility to apoptosis through the regulation of caspase-3 and NOS3 expression.

scholarly journals Structural proteins of Hepatitis C virus induce interleukin 8 production and apoptosis in human endothelial cells

2005 ◽  
Vol 86 (12) ◽  
pp. 3291-3301 ◽  
Author(s):  
Anuradha Balasubramanian ◽  
Neru Munshi ◽  
Margaret J. Koziel ◽  
Zongyi Hu ◽  
T. Jake Liang ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Neutralizing Antibodies ◽  
Caspase 3 ◽  
Umbilical Vein ◽  
Interleukin 8 ◽  
Functional Changes ◽  
Fas L ◽  
Induced Apoptosis

Hepatitis C virus (HCV) infection is associated with inflammation of liver endothelium, which contributes to the pathogenesis of chronic hepatitis. The mechanism of this endothelitis is not understood, since the virus does not appear to infect endothelial cells productively. Here, an ‘innocent bystander’ mechanism related to HCV proteins was hypothesized and it was investigated whether the binding of HCV particles to human endothelium induced functional changes in the cells. Exposure of human umbilical vein endothelial cells (HUVECs) to HCV-like particles (HCV-LPs) resulted in increased interleukin 8 (IL8) production and induction of apoptosis. The IL8 supernatants collected after stimulation of HUVECs with HCV-LPs, BV-GUS (control baculovirus containing β-glucuronidase) and appropriate controls were used to assay the transendothelial migration of neutrophils. This assay confirmed that HCV-LP-induced IL8 was functionally active. Using specific NF-κB inhibitors, it was also shown that HCV-LP-induced NF-κB activity mediated IL8 production in HUVECs. Apoptosis appeared to be mediated by the Fas/Fas-L pathway, as neutralizing antibodies for Fas and Fas-L significantly protected HUVECs against HCV-LP-induced apoptosis. Treatment of HUVECs with HCV-LPs also enhanced cellular Fas-L expression and augmented caspase-3 activation. This was confirmed by using a specific caspase-3 inhibitor, Z-Asp-Glu-Val-Asp-fluoromethyl ketone. As shown by blocking of specific chemokine receptors for IL8 on HUVECs, the induction of IL8 did not appear to contribute to HCV-LP-induced apoptosis. These results suggest that HCV proteins can trigger the release of inflammatory chemokines such as IL8 and cause endothelial apoptosis, thereby facilitating endothelitis.

Abstract 248: Stabilization of cIAP2 during Postconditioning protects Endothelial Cells from Reperfusion Injury

Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Krishnaveni Gadiraju ◽  
Frauke V Haertel ◽  
Hans M Piper ◽  
Thomas Noll
Keyword(s):  
Endothelial Cells ◽  
Protective Effect ◽  
Reperfusion Injury ◽  
Intermittent Hypoxia ◽  
Umbilical Vein ◽  
Fold Increase ◽  
Protective Mechanism ◽  
Second Phase ◽  
Induced Apoptosis ◽  
Hypoxia Reoxygenation

Hypoxia-reperfusion causes a perturbance in the complex equilibrium of pro and anti apoptotic mechanisms which ultimately leads to apoptosis in the reperfused myocardium. Postconditioning (intermittent hypoxia at the onset of reperfusion) is a proven strategy to reduce reperfusion injury, however, the mechanisms are largely unknown in endothelial cells. Here we analyze the effect of postconditioning in endothelial cells and hypothesize that the ‘inhibitors of apoptosis proteins’ (IAPs), known as antiapoptotic mediators, are key elements of this protective mechanism. Methods and Results: Exposure of human umbilical vein endothelial cells to severe hypoxia (Po 2 < 2 mmHg) for 2 hrs causes a 2.1±0.5-fold increase in caspase 3 activation (western blot analysis; P<0.05, n=3, for all further parameters) and a 2.3±04-fold increase in apoptosis (annexin V staining) after 24 hrs of reoxygenation. cIAP2 but not cIAP1 is rapidly increased during hypoxia in a biphasic manner. Transcription inhibitor, Actinomycin D (20μg/ml) reveals that the 2.5-fold increase within 5 min of hypoxia (first phase) was independent of transcription, but the 3.1-fold increase after 60 min (second phase) was induced by gene transcription. cIAP2 levels dropped down to basal value with the onset of reperfusion. Importantly, cIAP2 levels could be maintained by postconditioning (3 short periods of intermittent hypoxia, 5 minutes each separated by a 5 minute reoxygenation) which abolished hypoxia-reoxygenation-induced apoptosis. Down regulation of IAP2 by siRNA strategy enhanced hypoxia-reoxygenation-induced apoptosis and diminished the protective effect of postconditioning. Conclusions: The present study shows for the first time that postconditioning can protect endothelial cells against hypoxia-reoxygenation induced apoptosis. This protective effect is conferred by the cIAP2, which is stabilized during hypoxia and could be maintained at an elevated level by postconditioning.

scholarly journals Hepatocyte Growth Factor Inhibits Apoptosis by the Profibrotic Factor Angiotensin II via Extracellular Signal-regulated Kinase 1/2 in Endothelial Cells and Tissue Explants

2010 ◽  
Vol 21 (23) ◽  
pp. 4240-4250 ◽  
Author(s):  
Young H. Lee ◽  
Ana P. Marquez ◽  
Ognoon Mungunsukh ◽  
Regina M. Day
Keyword(s):  
Endothelial Cells ◽  
Growth Factor ◽  
Hepatocyte Growth Factor ◽  
Caspase 3 ◽  
Cytoplasmic Localization ◽  
Ang Ii ◽  
Extracellular Signal Regulated Kinase ◽  
Extracellular Signal ◽  
Induced Apoptosis ◽  
Hepatocyte Growth

Hepatocyte growth factor (HGF), an endogenous tissue repair factor, attenuates apoptosis in many primary cell types, but the mechanism is not completely understood. Our laboratory demonstrated that angiotensin (Ang) II activates the intrinsic apoptotic pathway in primary endothelial cells (ECs) via reduction of the antiapoptotic protein Bcl-xL. Ang II decreased Bcl-xLmRNA half-life by reducing its binding to nucleolin, a protein that normally binds a 3′ AU-rich region and stabilizes Bcl-xLmRNA. We hypothesized HGF may block apoptosis induced by Ang II. We used primary EC and ex vivo cultures of rat lung tissue to investigate HGF inhibition of Ang II-induced apoptosis. Our data indicated HGF abrogated Ang II-induced apoptosis by inhibiting cytochrome c release, caspase-3 activation, and DNA fragmentation. RNA-immunoprecipitation experiments demonstrated that HGF stabilized Bcl-xLmRNA by increasing nucleolin binding to the 3′-untranslated region that was associated with cytoplasmic localization of nucleolin. Cytoplasmic localization of nucleolin and Bcl-xLmRNA stabilization required HGF activation of extracellular signal-regulated kinase (ERK)1/2, but not phosphatidylinositol 3-kinase. HGF also blocked Ang II-induced caspase-3 activation and lactate dehydrogenase release in tissue explants in an ERK-dependent manner.

Inhibition of hypoxia/reoxygenation-induced apoptosis in metallothionein-overexpressing cardiomyocytes

2001 ◽  
Vol 280 (5) ◽  
pp. H2292-H2299 ◽  
Author(s):  
Guang-Wu Wang ◽  
Zhanxiang Zhou ◽  
Jon B. Klein ◽  
Y. James Kang
Keyword(s):  
Cytochrome C ◽  
Caspase 3 ◽  
Ischemia Reperfusion ◽  
Annexin V ◽  
Terminal Deoxynucleotidyl Transferase ◽  
Cytochrome C Release ◽  
Apoptotic Pathway ◽  
Fetal Bovine ◽  
Induced Apoptosis ◽  
Hypoxia Reoxygenation

To study possible mechanisms for metallothionein (MT) inhibition of ischemia-reperfusion-induced myocardial injury, cardiomyocytes isolated from MT-overexpressing transgenic neonatal mouse hearts and nontransgenic controls were subjected to 4 h of hypoxia (5% CO2-95% N2, glucose-free modified Tyrode's solution) followed by 1 h of reoxygenation in MEM + 20% fetal bovine serum (FBS) (5% CO2-95% air), and cytochrome c-mediated caspase-3 activation apoptotic pathway was determined. Hypoxia/reoxygenation-induced apoptosis was significantly suppressed in MT-overexpressing cardiomyocytes, as measured by both terminal deoxynucleotidyl transferase-mediated deoxyuridine 5-triphosphate nick-end labeling and annexin V-FITC binding. In association with apoptosis, mitochondrial cytochrome c release, as determined by Western blot, was observed to occur in nontransgenic cardiomyocytes. Correspondingly, caspase-3 was activated as determined by laser confocal microscopic examination with the use of FITC-conjugated antibody against active caspase-3 and by enzymatic assay. The activation of this apoptotic pathway was significantly inhibited in MT-overexpressing cells, as evidenced by both suppression of cytochrome c release and inhibition of caspase-3 activation. The results demonstrate that MT suppresses hypoxia/reoxygenation-induced cardiomyocyte apoptosis through, at least in part, inhibition of cytochrome c-mediated caspase-3 activation.

Protection of capsaicin against hypoxia–reoxygenation-induced apoptosis of rat hippocampal neurons

2008 ◽  
Vol 86 (11) ◽  
pp. 785-792 ◽  
Author(s):  
Shi-Yin Guo ◽  
Guo-Ping Yang ◽  
De-Jian Jiang ◽  
Feng Wang ◽  
Tao Song ◽  
...  
Keyword(s):  
Hippocampal Neurons ◽  
Caspase 3 ◽  
Specific Inhibitor ◽  
Cell Number ◽  
Pyrrolidine Dithiocarbamate ◽  
Pi3k Inhibitor Ly294002 ◽  
Phosphoinositide 3 Kinase ◽  
Induced Apoptosis ◽  
Survival Effect ◽  
Hypoxia Reoxygenation

The aim of this study was to investigate the effect of capsaicin on hypoxia–reoxygenation (H/R)-induced apoptosis in primary rat hippocampal neurons. Three hours of hypoxia (1% O2) and subsequent reoxygenation for 24 h significantly increased the apoptotic death of hippocampal neurons, as evidenced by increases in both TUNEL-positive cell number and caspase-3 activity. Pretreatment with capsaicin (3–30 µmol/L) or the caspase-3-specific inhibitor acetyl-DEVD-CHO (100 µmol/L) markedly attenuated H/R-induced apoptosis in hippocampal neurons. Capsaicin also markedly induced the phosphorylation of Akt. The phosphoinositide 3-kinase (PI3K) inhibitor LY294002 (10 µmol/L) prevented any capsaicin-induced survival effect in hippocampal neurons. Intracellular levels of reactive oxygen species (ROS), which were greatly increased after H/R, were significantly inhibited by capsaicin, pyrrolidine dithiocarbamate (PDTC) (50 µmol/L), and LY294002. Taken together, these data suggest that capsaicin protects against H/R-induced apoptosis of hippocampal neurons via the PI3K/Akt-mediated signaling pathway, which is related to the inhibition of oxidative stress and caspase-3 activation.

Sign in / Sign up

Export Citation Format

Share Document