Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P42574 (caspase-3)
 45,978 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Angiotensin II (Ang II) importantly contributes to the pathobiology of atherosclerosis. Since endothelial injury is a key event early in the pathogenesis of atherosclerosis, we tested the hypothesis that Ang II may injure endothelial cells by activation of cellular suicide pathways leading to apoptosis. Human umbilical venous endothelial cells (HUVECs) were incubated with increasing doses of Ang II for 18 hours. Apoptosis of HUVECs was measured by ELISA specific for histone-associated DNA fragments and confirmed by DNA laddering and nuclear staining. Ang II dose-dependently induced apoptosis of HUVECs. Simultaneous blockade of both the AT1 and AT2 receptor prevented Ang II-induced apoptosis, whereas each individual receptor blocker alone was not effective. Selective agonistic stimulation of the AT2 receptor also dose-dependently induced apoptosis. Ang II-mediated as well as selective AT2 receptor stimulation-mediated apoptosis was associated with the activation of caspase-3, a central downstream effector of the caspase cascade executing the cell death program. Specific inhibition of caspase-3 activity abrogated Ang II-induced apoptosis. In addition, the NO donors sodium nitroprusside and S-nitrosopenicillamine completely inhibited Ang II-induced apoptosis and eliminated caspase-3 activity. Thus, Ang II induces apoptosis of HUVECs via activation of the caspase cascade, the central downstream effector arm executing the cell death program. NO completely abrogated Ang II-induced apoptosis by interfering with the activation of the caspase cascade.
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PMID:Angiotensin II induces apoptosis of human endothelial cells. Protective effect of nitric oxide. 940 Mar 77

We have demonstrated that a novel Ste20-related kinase, designated SLK, mediates apoptosis and actin stress fiber dissolution through distinct domains generated by caspase 3 cleavage. Overexpression of SLK in C2C12 myoblasts stimulated the disassembly of actin stress fibers and focal adhesions and induced apoptosis, as determined by annexin V binding and terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling analysis. SLK was cleaved by caspase 3 in vitro and in vivo during c-Myc-, tumor necrosis factor alpha, and UV-induced apoptosis. Furthermore, cleavage of SLK released two domains with distinct activities: an activated N-terminal kinase domain that promoted apoptosis and cytoskeletal rearrangements and a C-terminus domain that disassembled actin stress fibers. Moreover, our analysis has identified a novel conserved region (termed the AT1-46 homology domain) that efficiently promotes stress fiber disassembly. Finally, transient transfection of SLK also activated the c-Jun N-terminal kinase signaling pathway. Our results suggest that caspase-activated SLK represents a novel effector of cytoskeletal remodeling and apoptosis.
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PMID:Caspase 3 cleavage of the Ste20-related kinase SLK releases and activates an apoptosis-inducing kinase domain and an actin-disassembling region. 1061 Dec 47

Apoptosis, a morphological form of programmed cell death required for control of cell populations, participates in reduced tissue volume associated with ventricular scarring. Prevention of apoptosis of excessive, damaged, or nonfunctioning cardiac or of infiltrating inflammatory cells is usually beneficial for the resolution of cardiac fibrosis. Angiotensin(Ang) II, the most important peptide that mediates the effects of the renin-angiotensin system, may play an important role in hypertension, hypertrophy, and interstitial fibrosis. Furthermore, AngII induced apoptosis of human venous endothelial cells, myocyte, and vascular smooth muscular cells by caspase cascade activation, and the both blockade of AngII type(AT)1 and AT2 receptor prevents AngII induced apoptosis, whereas selective agonistic stimulation of the AT2 receptor alone induces apoptosis. When AT1 or AT2 receptors are stimulated in vivo, apoptosis is enhanced in myocytes, myofibroblasts, and media smooth muscular cells. In the case of AT1 receptor stimulation, this may occur in cardiac myocytes secondary to ventricular hypertrophy. On the other hand, AT2 receptor stimulation induced apoptosis myofibroblasts associated with reduced interstitial fibrosis. Caspase-3 participates in the pathways of apoptosis triggered by in vivo AT1 and AT2 receptor stimulations.
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PMID:[Effects of angiotensin II type 1 and type 2 receptor on apoptosis]. 1239 79

The protective effects and roles of AT1-receptor antagonists (AT1-RA) or angiotensin-converting enzyme inhibitors (ACEI) on vascular endothelial cell (EC) injury during hypoxia are not entirely known. Therefore, we investigated these effects and mechanisms in human aortic (HA) EC. DNA fragmentation, Lactate dehydrogenase (LDH) release, and caspase-3 activity were measured in cultured HAEC after exposure to hypoxia in the presence or absence of an AT1-RA (candesartan, CS) and/or an ACEI (temocaprilat, TC). Next, we investigated endothelial cell nitric oxide synthase (ecNOS) and inducible (i) NOS to determine the role of the bradykinin(BK)-NO pathway in the protective effect on ACEI and AT1-RA in the setting of hypoxia-induced apoptosis. Exposure to hypoxia increased DNA fragmentation in HAEC associated with the activation of caspase-3, but did not affect LDH release. In addition, hypoxia induced ecNOS mRNA but not mRNA iNOS. CS and/or TC reduced apoptosis induced by hypoxia in a dose-dependent manner, and significantly increased BK and ecNOS expression. This effect was attenuated by the kinin B2 receptor antagonist, HOE 140, and the NOS inhibitor, N-nitro-L-arginine methylester (L-NMMA). Hypoxia activates the pathway leading to apoptosis by enhancing caspase-3 activity. Both CS and TC can ameliorate hypoxia-induced apoptosis in HAEC through inhibiting caspase-3 activation by enhancing ecNOS activity, via the accumulation of BK.
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PMID:An AT1-receptor antagonist and an angiotensin-converting enzyme inhibitor protect against hypoxia-induced apoptosis in human aortic endothelial cells through upregulation of endothelial cell nitric oxide synthase activity. 1278 10

Apoptosis of alveolar epithelial cells (AECs) has been implicated as a key event in the pathogenesis of lung fibrosis. Recent studies demonstrated a role for the synthesis and binding of angiotensin II to receptor AT1 in the induction of AEC apoptosis by bleomycin (BLEO) and other proapoptotic stimuli. On this basis we hypothesized that BLEO-induced apoptosis and lung fibrosis in mice would be inhibited by the AT1 antagonist losartan (LOS) or by targeted deletion of the AT1 gene. Lung fibrosis was induced by intratracheal administration of BLEO (1 U/kg) to wild-type C57BL/6J mice. Co-administration of LOS abrogated BLEO-induced increases in total lung caspase 3 activity detected 6 hours after in vivo administration and reduced by 57% BLEO-induced caspase 3 activity in blood-depleted lung explants exposed to BLEO ex vivo (both P < 0.05). Co-administration of LOS in vivo reduced DNA fragmentation and immunoreactive caspase 3 (active form) in AECs, measured at 14 days after intratracheal BLEO, by 66% and 74%, respectively (both P < 0.05). LOS also inhibited the accumulation of lung hydroxyproline by 45%. The same three measures of apoptosis and lung fibrosis were reduced by 89%, 85%, and 75%, respectively (all P < 0.01), in mice with a targeted disruption of the AT1a receptor gene (C57BL/6J-Agtr1a(tm1Unc)). These data indicate an essential role for angiotensin receptor AT1a in the pathogenesis of BLEO-induced lung fibrosis in mice and suggest that AT1 receptor signaling is required for BLEO-induced apoptosis of AECs in mice as it is in rat and human AECs.
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PMID:Essential roles for angiotensin receptor AT1a in bleomycin-induced apoptosis and lung fibrosis in mice. 1463 24

Arterial hypertension is a leading contributor to the progression of chronic renal disease. Short-term studies had addressed the role of oxidative stress in hypertensive nephropathy. We have now studied oxidative stress and caspase activation in a long-term model of hypertensive renal injury. Nontreated spontaneously hypertensive rats with uninephrectomy displayed severe arterial hypertension over a 36-week follow-up. Uncontrolled high blood pressure in the context of modest renal mass reduction resulted in significant histological renal injury. Blood pressure control by the angiotensin-converting enzyme (ACE) inhibitor, quinapril, or the AT1 receptor antagonist, losartan, decreased the degree of renal injury. Hypertensive renal injury was associated with evidence of activation of the apoptotic pathway (increased activation of caspase-3) and local renal (increased staining for 4-hydroxy-2-nonenal) and systemic [increased serum levels of 8-iso-prostaglandin F2alpha (8-iso-PGF2alpha)] lipid oxidation when compared with normotensive control rats. In addition, severe hypertension decreased the renal antioxidant defenses, as exemplified by decreased expression of Cu/Zn superoxide dismutase. Treatment with quinapril or losartan decreased caspase-3 activation, 4-hydroxy-2-nonenal staining, and 8-iso-PGF2alpha levels and increased Cu/Zn superoxide dismutase expression. These results suggest that hypertension-associated oxidative stress and its consequences may be decreased by either ACE inhibition or AT1 receptor antagonist, emphasizing the role of angiotensin II in hypertensive renal damage.
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PMID:Long-term blood pressure control prevents oxidative renal injury. 1611 34

We tested the hypothesis that activation Jak2, which is prominently involved in the up-regulation of the renin-angiotensin system (RAS), constitutes a focal point in relaying signals triggered by a Angiotensin II (Ang II) and hypoxia/reoxygenation separately to cause an enhanced susceptibility of cardiac myocyte to apoptotic cell death. Ang II-treated adult cardiomyocytes in culture exhibited an increased level of apoptosis that accompanied activation of pro-apoptotic as well as anti-apoptotic signaling pathways. We observed increased phosphorylation of Jak2 kinase, Stat1, JNK, with increased expression of Bax protein, followed by an increase in caspase-1 and caspase-3 activity. Activation of these pro-apoptotic pathways was blocked by the Jak2 pharmacological inhibitor, Tyrphostin AG490. We also observed an increase in phosphorylation of cardioprotective pathway components, namely S6 ribosomal protein, and heat shock protein 27 (HSP27). Likewise, the oxidative stress, via the hypoxia/reoxygenation treatment of rat adult cardiomyocytes, produced apoptosis that was dependent upon activation of Jak2. The apoptotic response was not only reduced by Losartan, an inverse agonist of the AT1, receptor, but by treatment with AG490 as well. Taken together, these observations provide clear evidence in favor of Jak2 signaling as mediator of the apoptotic response in cardiomyocytes. However, there was a concomitant induction of cytoprotective signaling that presumably provides a negative feed-back to the deleterious effects of the agonist.
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PMID:Janus kinase-2 signaling mediates apoptosis in rat cardiomyocytes. 1626 69

We investigated the effects of castration and androgen administration on angiotensin II receptor mRNA expression and apoptosis related proteins in the rat bladders. Sprague-Dawley rats were divided into three groups: the control group (sham operation; n = 8), the castration group (castrated, 8 weeks old, n = 8) and the castration plus testosterone group (1% testosterone gel administrated percutaneously into the dorsum daily for 8 weeks starting at 4 weeks after castration, n = 8). Bladder total RNA was extracted, and real-time PCR was performed to quantitatively measure the mRNA expression of angiotensin converting enzyme (ACE), angiotensin II (A II) receptor type 1 (AT1 receptor) and A II receptor type II (AT2 receptor). Western blotting was performed to determine the expression of apoptosis-related proteins. Expression of AT2 receptor mRNA and caspase-3 protein significantly increased in the rat bladder after castration, and these increases were reduced to control levels by testosterone administration. These results suggest that expression of AT2 receptor and caspase-3 in the bladder is androgen-dependent. Expression of Bcl-2 and Bax protein in the rat bladder was not altered by castration. Expression of mitogen-activated protein (MAP) kinase phosphatase-1 protein in the rat urinary bladder was significantly increased by castration, but this increase was smaller with testosterone administration. These results suggest that expression of AT2 receptor mRNA and apoptosis-related proteins in the rat urinary bladder are affected by the change of androgen environment. The present study was the first to clarify the relationship between AT2 receptor and androgen in the urinary bladder.
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PMID:Effects of castration and testosterone administration on angiotensin II receptor mRNA expression and apoptosis-related proteins in rat urinary bladder. 1723 11

The cellular stress response can mediate cellular protection through expression of heat shock protein (Hsp70), which can interfere with the process of apoptotic cell death. Factors regulating renal epithelial cell apoptosis include angiotensin II. In the present study, we have examined the relationship between the Hsp70 expression and the apoptotic pathway in the kidneys from low-protein-fed rats (8% protein). The possible cytoprotective role of Hsp70 has been evaluated during low-protein feeding and after reincorporation of 24% protein in the diet. The effect of angiotensin II AT1 receptor inhibition has also been studied. Rats were fed with a low-protein (LP) diet (8% protein) for 14 days, and then the animals were recovered by means of a normal protein diet (24% protein) (RP) for 14, 21, and 30 days, and control rats received 24% protein (NP) in the diet. LP and NP rats treated with Losartan (10 mg/kg) were also evaluated. The following methods were performed on the kidneys: terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling assay for apoptosis, reverse transcriptase-polymerase chain reaction assay for AT1, Bax, and Bcl-2 messenger ribonucleic acid (mRNA) expression, and immunohistochemical and Western blot for Hsp70 and caspase 3 protein expression and activity. In the LP group, the cells of the medullary ducts (MDs) showed increased apoptosis associated with weak immunoreaction for Hsp70 and decreased Hsp70 protein levels. In these animals, enhanced proapoptotic ratio Bax/Bcl-2 linked to decreased procaspase 3 protein levels with increased caspase 3 activation were demonstrated. A cytoprotection attributed to Hsp70 could be noted in the RP rats after 21 days of reincorporation of the normal diet, and in the LP-fed group treated with Losartan. In these cases, the MD cells displayed decreased apoptosis and increased Hsp70 expression in colocalization staining, and high Hsp70 levels in cytosolic fraction. A decreased proapoptotic ratio Bax/Bcl-2, associated with increased Bcl-2 mRNA, was also observed. Our results provide evidence for an antiapoptotic, cytoprotective effect of Hsp70 in kidney MD cells of rats with LP intake, when the animals were recovered with 24% protein in diet and after angiotensin II AT1 receptor inhibition. Angiotensin II seems to play a role in the pathogenesis of tubule epithelial cell apoptosis during LP feeding.
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PMID:Heat shock protein 70 expression is associated with inhibition of renal tubule epithelial cell apoptosis during recovery from low-protein feeding. 1727 80

In the microenvironment of solid growing tumors, pronounced hypoxia or extracellular acidosis is commonly found. The aim of this study was the analysis of the cytotoxic effect of different chemotherapeutic agents (cisplatin, daunorubicin, docetaxel) under these conditions in vitro. Prostate carcinoma cells (R3327-AT1) were exposed to hypoxia (pO2 < 0.5 mmHg) or extracellular acidosis (pH = 6.6) for 6h. After 3h, cytotoxic drugs were added. The cytotoxic effect was assessed by measuring caspase 3-activity (apoptosis), LDH release (necrosis) and repopulation of the cells after chemotherapy (cell death). Compared to aerobic control conditions, severe hypoxia over 6 h per se led to a slight increase in apoptosis, necrosis and cell death. With all three chemotherapeutic agents, hypoxia led to a reduced (by approx. 25%) caspase 3-activity and a marked increase in necrosis. However, the overall cytotoxicity of the drug was not affected by O2-deficiency. By contrast, during extracellular acidosis, the cytotoxic effect of daunorubicin was reduced by 40%, preferentially due to a marked reduction in apoptosis. With cisplatin and docetaxel no change in overall cell death was detected. However, for daunorubicin the tumor-pH seems to have a strong impact on cytotoxicity. With this chemotherapeutic drug the therapeutic efficacy is markedly reduced in an acidotic environment.
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PMID:Impact of hypoxic and acidic extracellular conditions on cytotoxicity of chemotherapeutic drugs. 1772 60


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