Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.22.56 (caspase-3)
 35,750 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

It is well known that inflammatory conditions of the intestinal mucosa result in compromised barrier function. Inflammation is characterized by an influx into the mucosa of immune cells that influence epithelial function by releasing proinflammatory cytokines such as IFN-gamma and TNF-alpha. Mucosal barrier function is regulated by the epithelial apical junctional complex (AJC) consisting of the tight junction and the adherens junction. Since the AJC regulates barrier function, we analyzed the influence of IFN-gamma and TNF-alpha on its structure/function and determined the contribution of apoptosis to this process using a model intestinal epithelial cell line, T84, and IFN-gamma and TNF-alpha. AJC structure/function was analyzed by confocal microscopy, biochemical analysis, and physiologic measurement of epithelial gate/fence function. Apoptosis was monitored by determining cytokeratin 18 cleavage and caspase-3 activation. IFN-gamma induced time-dependent disruptions in epithelial gate function that were potentiated by coincubation with TNF-alpha. Tight junction fence function was somewhat disrupted. Cytokine treatment was associated with internalization of AJC transmembrane proteins, junction adhesion molecule 1, occludin, and claudin-1/4 with minimal effects on the cytoplasmic plaque protein zonula occludens 1. Detergent solubility profiles of junction adhesion molecule 1 and E-cadherin and their affiliation with "raft-like" membrane microdomains were modified by these cytokines. Inhibition of cytokine-induced apoptosis did not block induced permeability defects; further emphasizing their primary influence on the epithelial AJC structure and barrier function. Our findings for the first time clearly separate the proapoptotic effects of IFN-gamma and TNF-alpha from their abilities to disrupt barrier function.
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PMID:Proinflammatory cytokines disrupt epithelial barrier function by apoptosis-independent mechanisms. 1463 32

Various human colon cancer cell lines tested in vitro differed significantly in susceptibility to growth inhibition of recombinant human interferon-beta (rHuIFN-beta). Two p53-mutant lines, COH and CC-M2, derived from high-grade colon adenocarcinoma, showed signs of apoptosis after treatment with 250 IU/ml of HuIFN- beta in the culture medium. The similarly p53-mutated HT-29 line from a grade I adenocarcinoma showed no apoptosis, however, and only cell cycle G1/G0 or S phase retardation with 1000 IU/ml HuIFN-beta. After HuIFN-beta exposure, COH and CC-M2 cells showed increased levels of Fas and FasL proteins, alteration of mitochondrial membrane potential, and activation of caspase-9, caspase-8, and caspase-3 in a time-dependent manner. Treatment of COH and CC-M2 cells with anti-FasL antibodies or rFas/Fc fusion protein, however, could not prevent the apoptosis induced by HuIFN-beta. In contrast, cell-permeable specific inhibitors of the three caspases could inhibit the DNA fragmentation and cell death but not the mitochondrial membrane potential changes. Treatment with mitochondria-stabilizing reagents could significantly abrogate the apoptosis and caspase activation induced by HuIFN-beta. These results suggest that in COH and CC-M2 colon cancer cell lines, HuIFN-beta induces apoptosis mainly through mitochondrial membrane alteration and subsequent activation of the caspase cascade pathway, but not by the Fas/FasL interaction or the p53-dependent apoptotic mechanism.
J Interferon Cytokine Res 2004 Apr
PMID:IFN-beta induces caspase-mediated apoptosis by disrupting mitochondria in human advanced stage colon cancer cell lines. 1514 69

The ubiquitin-proteasome pathway plays a critical role in the degradation of cellular proteins related to signal transduction. Cytokine and growth factor-dependent aberrant proliferation has been implicated in renal cell carcinoma (RCC). We hypothesized that inhibiting the proteasome function might activate a proapoptotic signal transduction by modulating the cytokine and growth factor related signal transduction pathway. We therefore investigated the effectiveness of a proteasome inhibitor in the treatment of RCC regarding the involvement of Mitogen-activated protein kinases (MAP kinases), because MAP kinases are major signal transduction molecules that are known to play a pivotal role in cancer cell proliferation or apoptosis triggered by extra-cellular cytokines and growth factors. A proteasome inhibitor, MG132 inhibited the proliferation of RCC cell lines, 786-O and KU20-01 in a time and dose-dependent manner. 786-O cells have truncated von-Hippel Lindau (VHL) tumor suppressor gene protein due to a one base pair deletion at exon 1, whereas KU20-01 cells have a wild-type VHL protein. MG132 induced apoptosis in both cell lines. The inhibition of the ubiquitin-proteasome pathways was confirmed by the accumulation of ubiquitin-tagged proteins. MG132 induced the phosphorylation of ERK at 4 h and thereafter persisted for 8 to 16 h. In contrast, JNK and p38 activation persisted for longer periods and remained enhanced until 24 h. The concomitant activation of effector caspases, caspase-3 and caspase-7 was observed in 786-O cells. The inhibition of the proteasome function can induce apoptosis in RCC irrespective of the VHL protein status. The persistence of JNK and p38 activation may therefore be a unique mechanism underlying MG132 induced apoptosis.
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PMID:Inhibition of the ubiquitin-proteasome pathway activates stress kinases and induces apoptosis in renal cancer cells. 1528 72

Preservation of endothelial functions with low-dose nitric oxide (NO) and inhibition of excessive production of NO from inducible NO synthase (iNOS) is a potential therapeutic approach for acute stroke. Based on this hypothesis, an NO modulator, S-nitrosoglutathione (GSNO) was used, which provided neuroprotection in a rat model of focal cerebral ischemia. Administration of GSNO after the onset of ischemia reduced infarction and improved cerebral blood flow. To understand the mechanism of protection, the involvement of inflammation in ischemic brain injury was examined. Treatment with GSNO reduced the expression of tumor necrosis factor-alpha, interleukin-1beta, and iNOS; inhibited the activation of microglia/macrophage (ED1, CD11-b); and downregulated the expression of leukocyte function-associated antigen-1 and intercellular adhesion molecule-1 in the ischemic brain. The number of apoptotic cells (including neurons) and the activity of caspase-3 were also decreased after GSNO treatment. Further, the antiinflammatory effect of GSNO on expression of iNOS and activation of NF-kappaB machinery in rat primary astrocytes and in the murine microglial cell line BV2 was tested. Cytokine-mediated expression of iNOS and activation of NF-kappaB were inhibited by GSNO treatment. That GSNO protects the brain against ischemia/reperfusion injury by modulating NO systems, resulting in a reduction in inflammation and neuronal cell death was documented by the results.
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PMID:S-Nitrosoglutathione reduces inflammation and protects brain against focal cerebral ischemia in a rat model of experimental stroke. 1564 46

NKT cells expressing phenotypic markers of both T and NK cells seem to be pivotal in murine models of immune-mediated liver injury, e.g., in Con A-induced hepatitis. Also alpha-galactosylceramide (alpha-GalCer), a specific ligand for invariant Valpha14 NKT cells, induces hepatic injury. To improve the comprehension of NKT-cell mediated liver injury, we investigated concomitants and prerequisites of alpha-GalCer-induced hepatitis in mice. Liver injury induced by alpha-GalCer injection into C57BL/6 mice was accompanied by intrahepatic caspase-3 activity but appeared independent thereof. alpha-GalCer injection also induces pronounced cytokine responses, including TNF-alpha, IFN-gamma, IL-2, IL-4, and IL-6. We provide a detailed time course for the expression of these cytokines, both in liver and plasma. Cytokine neutralization revealed that, unlike Con A-induced hepatitis, IFN-gamma is not only dispensable for alpha-GalCer-induced hepatotoxicity but even appears to exert protective effects. In contrast, TNF-alpha was clearly identified as an important mediator for hepatic injury in this model that increased Fas ligand expression on NKT cells. Whereas intrahepatic Kupffer cells are known as a pivotal source for TNF-alpha in Con A-induced hepatitis, they were nonessential for alpha-GalCer-mediated hepatotoxicity. In alpha-GalCer-treated mice, TNF-alpha was produced by intrahepatic lymphocytes, in particular NKT cells. BALB/c mice were significantly less susceptible to alpha-GalCer-induced liver injury than C57BL/6 mice, in particular upon pretreatment with d-galactosamine, a hepatocyte-specific sensitizer to TNF-alpha-mediated injury. Finally, we demonstrate resemblance of murine alpha-GalCer-induced hepatitis to human autoimmune-like liver disorders. The particular features of this model compared with other immune-mediated hepatitis models may enhance comprehension of basic mechanisms in the etiopathogenesis of NKT cell-comprising liver disorders.
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PMID:Alpha-galactosylceramide-induced liver injury in mice is mediated by TNF-alpha but independent of Kupffer cells. 1603 92

The antiviral, antiproliferative and immunomodulatory effects of type I interferons (IFNs) are well documented, however, few studies have been published concerning differences in the antitumor effects of IFN-alpha and beta. In the present study, differences in antitumor effect, including the antiproliferative effect, cell cycle change, apoptosis, and the IFN-stimulated gene (ISG) were examined by flow cytometry between IFN-alpha and beta on three human hepatocellular carcinoma (HCC) cell lines (HepG2, Huh7 and JHH4). The antiproliferative effect of both IFNs on the HCC cell lines was time- and dose-dependent, and IFN-beta was significantly stronger than IFN-alpha. The cell cycle effect by both IFNs was an S-phase accumulation, with IFN-beta having a tendency to increase the S-phase ratio more strongly than IFN-alpha, especially in Huh7. Apoptosis marker expression, Fas antigen and intracellular active caspase-3, was increased after the addition of IFNs, especially of IFN-beta. The expression of human leukocyte antigen-class I molecules, ISG-encoded protein, was increased after the addition of IFNs, especially of IFN-beta. These data suggest that IFN-beta has a greater antitumor effect than IFN-alpha on HCC of a very early stage in patients with chronic hepatitis C.
Cytokine 2006 Feb 07
PMID:A comparison of the antitumor effects of interferon-alpha and beta on human hepatocellular carcinoma cell lines. 1652 72

Inflammation contributes to the pathogenesis of atherosclerosis. Proinflammatory cytokines, including interleukin-1 (IL-1), may be involved in the local inflammation occurring in the vessel wall. Vascular smooth muscle cells express the unprocessed IL-1beta precursor molecule. Invading leukocytes, such as monocytes or polymorphonuclear granulocytes (PMN) may activate the IL-1beta precursor during atherogenesis. Thus, we investigated the capacity of PMN to process IL-1beta and IL-18 precursors. Processing was analyzed using Western blot and bioassay for IL-1-activity was performed. As few as 80 to 400 PMN/mL detectably processed preIL-1beta. PMN also cleaved the caspase-1 substrate preIL-18. The preIL-1beta and preIL-18 cleavage products were located at the same apparent molecular weight as those resulting from cleavage by monocyte-derived caspase-1. PMN expressed caspase-1 mRNA and immunoreactive protein. The N-terminus of the preIL-1beta cleavage product expressed the sequence expected for caspase-1 cleavage. The cleavage product was active in the bioassay for IL-1 activity, and the caspase-1 inhibitor YVAD blocked processing. We have shown previously that SMC can block processing of preIL-1 by caspase-1. In contrast, SMC do not block processing of PARP by caspase-3. Here, we show that SMC also inhibited the PMN-mediated processing of recombinant and native preIL-1beta or preIL-18 depending on the cell number, whereas EC or fibroblasts did not block processing. Our results indicate that PMN can activate preIL-1beta in a caspase-1-like fashion. During inflammatory processes, PMN may activate preIL-1beta released from SMC, thereby altering IL-1-mediated cardiovascular functions, including contractility, apoptosis, and cytokine production.
Eur Cytokine Netw 2006 Mar
PMID:Neutrophils process interleukin-1beta and interleukin-18 precursors in a caspase-1-like fashion--processing is inhibited by human vascular smooth muscle cells. 1661 59

Childhood chronic inflammatory disease can be associated with transient and permanent growth retardation. This study examined the potential for spontaneous growth recovery following pro-inflammatory cytokine exposure. Murine ATDC5 chondrogenic cells and postnatal metatarsals were exposed to interleukin (IL)-1beta, IL-6 and tumour necrosis factor-alpha (TNFalpha), and their growth and proliferative capacity were determined following recovery. TNFalpha and IL-1beta reduced chondrocyte proliferation and aggrecan and collagen types II and X expression at minimum concentrations of 10 ng/ml and 0.1 ng/ml respectively. TNFalpha but not IL-1beta exposure led to increased caspase-3 activity and altered cellular morphology, consistent with reduced viability. Cytokine exposure particularly inhibited proteoglycan synthesis. This effect was dose and duration dependent. Compared with the control, IL-1beta and TNFalpha led to a 71% and 45% reduction in metatarsal growth after 8 days of exposure respectively (P < 0.05). An additive effect of IL-1beta combined with TNFalpha was observed (110% decrease; P < 0.05). Metatarsals exposed to IL-1beta or TNFalpha individually for a 2-day period, and allowed to recover spontaneously in the absence of cytokines for a further 6 days, showed normal growth trajectories. In combination, growth was 59% lower (P < 0.01) compared with control metatarsals at the end of the recovery period. Exposure to the combination for 4 days followed by a 4-day recovery period resulted in 87% decrement compared with controls (P < 0.05). IL-6 did not alter any parameter studied. IL-1beta and TNFalpha exert diverse inhibitory effects on ATDC5 chondrocyte dynamics and metatarsal growth. The extent of recovery following cytokine exposure depends on the duration of exposure, and may be incomplete following longer periods of exposure.
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PMID:The restricted potential for recovery of growth plate chondrogenesis and longitudinal bone growth following exposure to pro-inflammatory cytokines. 1664 99

Malignant cancers commonly spread by local invasion followed by metastasis through venous or lymphatic passages or both to distant sites. Angiogenesis and its relation to tumor growth and metastasis have been extensively researched. To date, however, the role played by lymphangiogenesis and metastasis of cancer has been overlooked. Inhibition of lymphangiogenesis, compared with inhibition of angiogenesis, may provide new insight to the mechanisms of metastasis of cancers. The current study was designed to examine the effect of two commonly used inhibitors of angiogenesis, interferon-alpha (IFN-alpha ) and IFN-gamma, on the growth and proliferation of lymphatic endothelial (LE) cells isolated from pig thoracic duct under in vitro condition. The LE cells were isolated and marked using specific markers, such as VEGFR-3 and LYVE-1, before experimental studies. The results showed that treatment of LE cells derived from the thoracic duct with these two inhibitors caused a decrease in the rate of cell proliferation in a dose-dependent manner, as assessed by MTT assays (tetrazolium salt colorimetric assay). Cell migration rate was assessed by the speed at which the cell migrated out from the scrape-wound margin; the speed of migration of LE cells was significantly inhibited in a dose-dependent fashion compared with controls. Treatment with both IFN-alpha and IFN-gamma caused an increase in apoptosis of LE cells, as assessed by Hoechst staining and caspase-3 staining. Our results showed that both IFN-alpha and IFN-gamma were able to inhibit LE cell growth in a dose-dependent manner and that the inhibition may be through induction of apoptosis of endothelial cells.
J Interferon Cytokine Res 2006 Aug
PMID:Influence of IFN- alpha and IFN- gamma on lymphangiogenesis. 1688 67

The proinflammatory cytokine, interleukin-18 (IL-18), is a natural killer (NK) cell activator that induces NK cell cytotoxicity and interferon-gamma (IFN-gamma) expression. In this report, we define a novel role for IL-18 as an NK cell protective agent. Specifically, IL-18 prevents NK cell death initiated by different and distinct stress mechanisms. IL-18 reduces NK cell self-destruction during NK-targeted cell killing, and in the presence of staurosporin, a potent apoptotic inducer, IL-18 reduces caspase-3 activity. The critical regulatory step in this process is downstream of the mitochondrion and involves reduced cleavage and activation of caspase-9 and caspase-3. The ability of IL-18 to regulate cell survival is not limited to a caspase death pathway in that IL-18 augments tumor necrosis factor (TNF) signaling, resulting in increased and prolonged mRNA expression of c-apoptosis inhibitor 2 (cIAP2), a prosurvival factor and caspase-3 inhibitor, and TNF receptor-associated factor 1 (TRAF1), a prosurvival protein. The cumulative effects of IL-18 define a novel role for this cytokine as a molecular survival switch that functions to both decrease cell death through inhibition of the mitochondrial apoptotic pathway and enhance TNF induction of prosurvival factors.
J Interferon Cytokine Res 2006 Oct
PMID:The proinflammatory cytokine interleukin-18 alters multiple signaling pathways to inhibit natural killer cell death. 1703 65


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