Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
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Target Concepts:
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Query: EC:3.4.22.36 (
caspase-1
)
6,285
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Fas/APO-1 and p55 tumor necrosis factor (TNF) receptor (
p55-R
) activate cellular mechanisms that result in cell death. Upon activation of these receptors, Fas/APO-1 binds a protein called MORT1 (or FADD) and
p55-R
binds a protein called TRADD. MORT1 and TRADD can also bind to each other. We have cloned a novel protein, MACH, that binds to MORT1. This protein exists in multiple isoforms, some of which contain a region that has proteolytic activity and shows marked sequence homology to proteases of the
ICE
/CED-3 family. Cellular expression of the proteolytic MACH isoforms results in cell death. Expression of MACH isoforms that contain an incomplete
ICE
/CED-3 region provides effective protection against the cytotoxicity induced by Fas/APO-1 or
p55-R
triggering. These findings suggest that MACH is the most upstream enzymatic component in the Fas/APO-1- and
p55-R
-induced cell death signaling cascades.
...
PMID:Involvement of MACH, a novel MORT1/FADD-interacting protease, in Fas/APO-1- and TNF receptor-induced cell death. 868 76
The two apoptosis receptors of mammalian cells, i.e. the 55 kDa TNF receptor (
TNF-R1
) and CD95 (Fas/APO1) are activated independently of each other, however, their signaling involves a variety of
ICE
-related proteases [I]. We used a cell-permeable inhibitor of
ICE
-like protease activity to examine in vivo whether post-receptor signaling of TNF and CD95 are fully independent processes. Mice pretreated with the inhibitor, Z-VAD-fluoromethylketone (FMK) were dose-dependently protected from liver injury caused by CD95 activation as determined by plasma alanine aminotransferase and also from hepatocyte apoptosis assessed by DNA fragmentation (ID50 = 0.1 mg/kg). A dose of 10 mg/kg protected mice also from liver injury induced by TNF-alpha. Similar results were found when apoptosis was initiated via TNF-alpha or via CD95 in primary murine hepatocytes (IC50 = 1.5 nM) or in various human cell lines. In addition to prevention, an arrest of cell death by Z-VAD-FMK was demonstrated in vivo and in vitro after stimulation of apoptosis receptors. These findings show in vitro and in vivo in mammals that CD95 and the TNF-alpha receptor share a distal proteolytic apoptosis signal.
...
PMID:ICE-protease inhibitors block murine liver injury and apoptosis caused by CD95 or by TNF-alpha. 909 74
Tumor necrosis factor (TNF)alpha is considered to play a key pathogenetic role in inflammatory bowel diseases. In this study we analyzed the mechanisms by which TNFalpha induces intestinal epithelial cell apoptosis. TNFalpha alone, and more potently in combination with IFNgamma, induced a high degree of IEC-6 cell apoptosis. This effect was more than 100-fold stronger if both of the
TNF-R
were stimulated, compared to stimulation of the p55-
TNF-R
alone, indicating an important apoptosis enhancing effect of the p75-
TNF-R
. TNFalpha-induced apoptosis required activation of
ICE
caspases and was completely abolished by its inhibitor, zVAD-fmk. Specific inhibition of caspase-3 with zDEVD-fmk did not alter the effect of TNFalpha. Western blot analyses confirmed that caspase-3 was not activated in response to TNFalpha. In the presence of complete inhibition of the caspase cascade with zVAD-fmk (>/=50 microM), TNFalpha induced cell necrosis rather than apoptosis. Our data reveal that TNFalpha can trigger enterocyte cell death via apoptosis or necrosis, depending upon the activation or blockade of specific caspases.
...
PMID:TNFalpha-induced IEC-6 cell apoptosis requires activation of ICE caspases whereas complete inhibition of the caspase cascade leads to necrotic cell death. 1038 60
The activities of
caspase-1
and caspase-3 were measured by use of fluoropeptides as substrates for the first time in the brain (substantia nigra, caudate nucleus, putamen, cerebellum, and frontal cortex) from control and parkinsonian patients. The activities of caspases in the brain were significantly higher in the substantia nigra from parkinsonian patients than those in the brain from control patients (p < 0.01). However, the activities of caspases in the caudate nucleus, putamen, cerebellum, and frontal cortex showed no significant difference between parkinsonian and control patients. The tumor necrosis factor (TNF) receptor R1 (
TNF-R1
, p55) level was also elevated in the substantia nigra of the parkinsonian brain in comparison with that of controls (p < 0.05). Since both caspases and
TNF-R1
may play important roles in apoptotic cell death through TNF-alpha-induced signaling pathway, our present data suggest the presence of a proapoptotic environment in the substantia nigra of parkinsonian brain, probably inducing vulnerability of neurons and glias towards a variety of noxious factors.
...
PMID:Caspase activities and tumor necrosis factor receptor R1 (p55) level are elevated in the substantia nigra from parkinsonian brain. 1082 42
Degeneration of the dopamine (DA) neurons of the substantia nigra pars compacta and the resulting loss of nerve terminals accompanied by DA deficiency in the striatum are responsible for most of the movement disturbances called parkinsonism, observed in Parkinson's disease (PD). One hypothesis of the cause of degeneration of the nigrostriatal DA neurons is that PD is caused by programmed cell death (apoptosis) due to increased levels of cytokines and/or decreased ones of neurotrophins. We and other workers found markedly increased levels of cytokines, such as tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-2, IL-4, IL-6, transforming growth factor (TFG)-alpha, TGF-beta1, and TGF-beta2, and decreased ones of neurotrophins, such as brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF), in the nigrostriatal DA regions and ventricular and lumbar cerebrospinal fluid of PD patients. Furthermore, the levels of TNF-alpha receptor R1 (
TNF-R1
, p55), bcl-2, soluble Fas (sFas), and the activities of
caspase-1
and caspase-3 were also elevated in the nigrostriatal DA regions in PD. In experimental animal models of PD, IL-1beta level was increased and NGF one decreased in the striatum of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced parkinsonian mice, and TNF-alpha level was increased in the substantia nigra and striatum of the 6-hydroxydopamine (6OHDA)-injected side of hemiparkinsonian rats. L-DOPA alone or together with 6OHDA does not increase the level of TNF-alpha in the brain in vivo. Increased levels of proinflammatory cytokines, cytokine receptors and caspase activities, and reduced levels of neurotrophins in the nigrostriatal region in PD patients, and in MPTP- and 6OHDA-produced parkinsonian animals suggest increased immune reactivity and programmed cell death (apoptosis) of neuronal and/or glial cells. These data indicate the presence of such proapoptotic environment in the substantia nigra in PD that may induce increased vulnerability of neuronal or glial cells towards a variety of neurotoxic factors. The probable causative linkage among the increased levels of proinflammatory cytokines and the decreased levels of neurotrophins, candidate parkinsonism-producing neurotoxins such as isoquinoline neurotoxins (Review; Nagatsu, 1997), and the genetic susceptibility to toxic factors, remains for further investigation in the molecular mechanism of PD. The increased cytokine levels, decreased neurotrophin ones, and the possible immune response in the nigrostriatal region in PD indicate new neuroprotective therapy including nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin, immunosuppressive or immunophilin-binding drugs such as FK-506, and drugs increasing neurotrophins.
...
PMID:Changes in cytokines and neurotrophins in Parkinson's disease. 1120 47
Some murine leukemia viruses (MuLVs), among them Cas-Br-E and ts-1 MuLVs, are neurovirulent, inducing spongiform myeloencephalopathy and hind limb paralysis in susceptible mice. It has been shown that the env gene of these viruses harbors the determinant of neurovirulence. It appears that neuronal loss occurs by an indirect mechanism, since the target motor neurons have not been found to be infected. However, the pathogenesis of the disease remains unclear. Several lymphokines, cytokines, and other cellular effectors have been found to be aberrantly expressed in the brains of infected mice, but whether these are required for the development of the neurodegenerative lesions is not known. In an effort to identify the specific effectors which are indeed required for the initiation and/or development of spongiform myeloencephalopathy, we inoculated gene-deficient (knockout [KO]) mice with ts-1 MuLV. We show here that interleukin-6 (IL-6), inducible nitric oxide synthetase (iNOS),
ICE
, Fas, Fas ligand (FasL), and
TNF-R1
KO mice still develop signs of disease. However, transgenic mice overexpressing Bcl-2 in neurons (NSE/Bcl-2) were largely protected from hind limb paralysis and had less-severe spongiform lesions. These results indicate that motor neuron death occurs in this disease at least in part by a Bcl-2-inhibitable pathway not requiring the
ICE
, iNOS, Fas/FasL,
TNF-R1
, and IL-6 gene products.
...
PMID:Protection against murine leukemia virus-induced spongiform myeloencephalopathy in mice overexpressing Bcl-2 but not in mice deficient for interleukin-6, inducible nitric oxide synthetase, ICE, Fas, Fas ligand, or TNF-R1 genes. 1464 73