Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P05412 (c-Jun)
 11,453 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Acetaminophen (AAP), a widely used analgesic drug, can damage various organs when taken in large doses. In this study, we investigate whether AAP causes cell damage by altering the early signaling pathways associated with cell death and survival. AAP caused time- and concentration-dependent apoptosis and DNA fragmentation of C6 glioma cells used as a model. AAP activated c-Jun N-terminal protein kinase (JNK) by 5.3-fold within 15 min. The elevated JNK activity persisted for up to 4 h before it returned to the basal level at 8 h. In contrast, activities of other mitogen-activated protein (MAP) kinases and the level of Akt phosphorylation in the cell survival pathway remained unchanged throughout the treatment. Wortmannin, an inhibitor of phosphatidylinositol-3 kinase, or SB203580, an inhibitor of p38 MAP kinase, did not reduce AAP-induced toxicity, indicating that these enzymes do not play a major role in cell toxicity. AAP-induced apoptosis was preceded by the sequential elevation of the pro-apoptotic Bax protein, cytochrome c release, and caspase-3 activity. Treatment with caspase inhibitor benzyloxycarbonyl-Asp-Glu-Val-Asp-fluoromethyl ketone (Z-DEVD-FMK) significantly reduced AAP-induced caspase-3 activation and cytotoxicity. Transfection of cDNA for the dominant-negative mutant JNK-KR or stress-activated protein kinase kinase-1 Lys-->Arg mutant (SEK1-KR), an immediate upstream kinase of JNK, significantly reduced AAP-induced JNK activation and cell death rate. The noncytotoxic analog of AAP, 3-hydroxyacetanilide, neither increased JNK activity nor caused apoptosis. Pretreatment with YH439, an inhibitor of CYP2E1 gene transcription, markedly reduced CYP2E1 mRNA, protein content, and activity, as well as the rate of AAP-induced JNK activation and cell death. These data indicate that AAP can cause cell damage by activating the JNK-related cell death pathway, providing a new mechanism for AAP-induced cytotoxicity.
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PMID:Acetaminophen induces apoptosis of C6 glioma cells by activating the c-Jun NH(2)-terminal protein kinase-related cell death pathway. 1156 48

Benzo[a]pyrene [B(a)P], a potent procarcinogen found in combustion products such as diesel exhaust and cigarette smoke, has been recently shown to activate the c-Jun NH(2)-terminal kinase 1 (JNK1) and induce caspase-3-mediated apoptosis in Hepa1c1c7 cells. However, the molecules of the signaling pathway that control the mitogen-activated protein kinase cascades induced by B(a)P and the interaction between those and apoptosis by B(a)P have not been well defined. We report here that B(a)P promoted Cdc42/Rac1, p21-activated kinase 1 (PAK1), and JNK1 activities in 293T and HeLa cells. Moreover, alpha-PAK-interacting exchange factor (alpha PIX) mRNA and its protein expression were upregulated by B(a)P. While overexpression of an active mutant of alpha PIX (DeltaCH) facilitated B(a)P-induced activation of Cdc42/Rac1, PAK1, and JNK1, overexpression of mutated alphaPIX (L383R, L384S), which lacks guanine nucleotide exchange factor activity, SH3 domain-deleted alphaPIX (Delta SH3), which lacks the ability to bind PAK, kinase-negative PAK1 (K299R), and kinase-negative SEK1 (K220A, K224L) inhibited B(a)P-triggered JNK1 activation. Interestingly, overexpression of alphaPIX (Delta CH) and a catalytically active mutant PAK1 (T423E) accelerated B(a)P-induced apoptosis in HeLa cells, whereas alphaPIX (Delta SH3), PAK1 (K299R), and SEK 1 (K220A, K224L) inhibited B(a)P-initiated apoptosis. Finally, a preferential caspase inhibitor, Z-Asp-CH2-DCB, strongly blocked the alphaPIX (Delta CH)-enhanced apoptosis in cells treated with B(a)P but did not block PAK1/JNK1 activation. Taken together, these results indicate that alphaPIX plays a crucial role in B(a)P-induced apoptosis through activation of the JNK1 pathway kinases.
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PMID:Involvement of alpha-PAK-interacting exchange factor in the PAK1-c-Jun NH(2)-terminal kinase 1 activation and apoptosis induced by benzo[a]pyrene. 1156 64

Excitotoxicity is considered a major cell death inductor in neurodegeneration. Yet mechanisms involved in cell death and cell survival following excitotoxic insults are poorly understood. Expression of active, phosphorylation-dependent mitogen-activated extracellular signal-regulated kinases (MAPK/ERKs), stress activated c-Jun N-terminal kinases (SAPK/JNKs) and p38 kinases, as well as their putative active specific transcriptional factor substrates CREB, Elk-1, ATF-2, c-Myc and c-Jun, have been examined following intracortical injection of the glutamate analogue quinolinic acid (QA). Increased JNK(P) and p38(P) immunoreactivity has been found in the core at 1 h following QA injection, whereas increased MAPK(P) immunoreactivity occurs in neurons and glial cells localised around the lesion and in neurons in remote cortical regions. This is accompanied by strong phosphorylated Ser63 c-Jun (c-Jun(P)) immunoreactivity in the core at 3 h, and by strong phosphorylated CREB, Elk-1 and ATF-2 (CREB(P), Elk-1(P) and ATF-2(P)) immunoreactivity mainly in neurons around the core at 24 h following QA injection. Examination with the method of in situ end-labelling of nuclear DNA fragmentation has revealed large numbers of positive cells with no apoptotic morphology in the core at 24 h, thus indicating that JNK(P), p38(P) and c-Jun(P) over-expression precedes cell death. In contrast, MAPK(P), CREB(P), Elk-1(P) and ATF-2(P), but not phosphorylated c-Myc (c-Myc(P)), over-expression correlates with cell survival. Examination of cleaved, active caspase-3 has shown specific immunoreactivity restricted to a few hematogenous cells in the area of injection. Since cleaved caspase-3 is not expressed by dying cells in the present paradigm, JNK(P), p38(P) and c-Jun(P) expression is not associated with caspase-3 activation. The present results demonstrate selective activation of specific MAPK signals which are involved either in cell death or cell survival triggered by excitotoxic insult.
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PMID:Differential expression of active, phosphorylation-dependent MAP kinases, MAPK/ERK, SAPK/JNK and p38, and specific transcription factor substrates following quinolinic acid excitotoxicity in the rat. 1159 64

Opiate addicts are prone to recurrent infections. In the present study we evaluated the molecular mechanism of opiate-induced T cell apoptosis. Both morphine and DAGO ([D-Ala2,N-Me-Phe4,Gly5-ol]enkephalin) enhanced T cell apoptosis. Morphine as well as DAGO activated c-Jun NH2-terminal kinase (JNK) in T cells. Moreover, opiates increased the expression of ATF-2. a specific substrate for JNK and P38 mitogen activated kinases (MAPK). Furthermore, opiates attenuated extracellular signal related kinase (ERK) in T cells. Both morphine and DAGO cleaved pro-caspases 8, 9, and 10 and generated caspases 8, 9 and 10 (active products). Morphine as well as DAGO also cleaved poly-(ADP-ribose) polymerase (PARP) into 116 and 85 kD proteins indicating the activation of caspase-3. These results suggest that opiate-induced T cell apoptosis may be mediated through the JNK cascade and activation of caspases 8 and 3.
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PMID:Opiates promote T cell apoptosis through JNK and caspase pathway. 1172 58

It is generally accepted that apoptosis occurs in human endometrium through the late secretory to menstruating phases. We found that Bcl-2 expression showed a cyclic pattern, peaking during the late proliferative phase. The decreased Bcl-2 in human endometrial glandular cells during the secretory phase was consistent with the appearance of apoptotic cells during the same phase. The expression patterns of both Sp-3 and c-Jun in glandular cells were similar to that observed in Bcl-2. Therefore, Sp-3 and c-Jun could be candidates for bcl-2 transcriptional factors in the human endometrium. In contrast to Bcl-2, both Fas and Fas ligand in glandular cells were coexpressed throughout the menstrual cycle. In particular, glandular cells showed the most intense expression of Fas ligand from the secretory to menstruating phases. The activities of caspase-3, -8 and -9 were higher from the secretory to menstruating phases than during the proliferating phase. We therefore conclude that bcl-2 transcription in glandular cells may be promoted by the binding of several transcriptional molecules to bcl-2 promoter, and the translated Bcl-2 blocks the release of cytochrome c from mitochondria to the cytosol during the proliferative phase. During the secretory phase, glandular cells may undergo apoptotsis via both death-receptor and mitochondrial pathways.
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PMID:Apoptosis in human endometrium: apoptotic detection methods and signaling. 1179 92

In retinitis pigmentosa, retinal detachment, age-related macular degeneration, and glaucoma, retinal neuronal cells are damaged by a common mechanism, apoptosis. Because apoptosis is an active process that requires de novo expression of a "death message", this process can be controlled by inhibiting the expression of the "death message". We first studied whether a retinal ischemia-reperfusion model can be used as a model for retinal neuronal apoptosis. In the retinal ischemia-reperfusion injuries, typical features of apoptosis, including TUNEL-positive cells, DNA ladder formation, and ultrastructural features of apoptosis were found. Using the model, systematic research to identify the "death message" was done by DNA microarray analysis. About 200 messages were found to be up- or down-regulated during the process of retinal ischemia-reperfusion. These genes were divided into four groups: (1) transcription factor genes, (2) cell cycle-related genes, (3) reactive oxygen scavenger genes and (4) molecular chaperon genes. The possible roles of such genes in neuronal apoptosis following retinal ischemia-reperfusion injury were studied. In the model, reactive oxygen species produced by reperfusion was found to generate lipid peroxides and induced up-regulation of a transcription factor, c-Jun, that further induced aberrant expression of cell cycle-related genes such as cyclin D1 in amacrine cells. However, because no controlled expression of cell cycle-related genes takes place in retinal neurons, amacrine cells died by a G1 arrest mechanism. On the other hand, horizontal cells never expressed cyclin D1 and the cells were found to die by necrosis. The study revealed a possible mechanism of retinal neuronal apoptosis and it also became apparent that different types of neurons use different "death messages". Furthermore, the possibility that inhibition of a "death message" sometimes induces necrosis rather than apoptosis was shown. This means that we need to try inhibition of the death mechanism upstream rather than downstream. Administration of thioredoxin, an endogenous reactive oxygen species that blocks generation of lipid peroxides and thus inhibits the death process upstream, was found to be neuroprotective against retinal ischemia-reperfusion injury. Aberrant expression of c-Jun and cyclin D1 was down-regulated by the treatment. Possible roles of caspases were also studied by using the ischemia-reperfusion injury, RCS rat, and excessive light exposure damage in wild type and caspase-1 deficient mice. Also, application of adeno-associated virus that carries Bcl-xL was tested to find possible neuroprotective effects on RCS rats. Our studies showed that caspase-1 played a more important role in the retinal photoreceptors and caspase-3 was important in neurons in the inner nuclear layer. Caspase-2 was found to be a major caspase in the retinal ganglion cell layer. In agreement with the findings, caspase-1 deficient mice showed less prominent light damage than wild type mice. Gene therapy by Bcl-xL was effective to protect retinal photoreceptor damage in RCS rats.
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PMID:[Retinal neuronal cell death: molecular mechanism and neuroprotection]. 1180 59

The expression of mitogen-activated protein kinases, extracellular signal-regulated kinases (MAPK/ERK), stress-activated protein kinases, c-Jun N-terminal kinases (SAPK/JNK), and p38 kinases is examined in Parkinson disease (PD), in Dementia with Lewy bodies (DLB), covering common and pure forms, and in age-matched controls. The study is geared to gaining understanding about the involvement of these kinases in the pathogenesis of Lewy bodies (LBs) and associated tau deposits in Alzheimer changes in the common form of DLB. Active, phosphorylation dependent MAPK (MAPK-P) is found as granular cytoplasmic inclusions in a subset of cortical neurons bearing abnormal tau deposits in common forms of DLB. Phosphorylated p-38 (p-38-P) decorates neurons with neurofibrillary tangles and dystrophic neurites of senile plaques in common forms of DLB. Phosphorylated SAPK/JNK (SAPK/JNK-P) expression occurs in cortical neurons with neurofibrillary tangles in the common form of DLB. Lewy bodies (LBs) in the brain stem of PD and DLB are stained with anti-ERK-2 antibodies, but they are not recognized by MAPK-P, SAPK/JNK-P and p-38-P. Yet MAPK-P, p-38-P and SAPK/JNK-P immunoreactivity is found in cytoplasmic granules in the vicinity of LBs or in association with irregular-shaped or diffuse alpha-synuclein deposits in a small percentage of neurons, not containing phosphorylated tau, of the brain stem in PD and DLB. MAPK-P, p-38-P and SAPK-P are not expressed in cortical LBs or in cortical neurons with alpha-synuclein-only inclusions in DLB. MAPK-P, p-38-P and SAPK/JNK-P are not expressed in alpha-synuclein-positive neurites (Lewy neurites) in PD and DLB as revealed by double-labeling immunohistochemistry. These results show that MAPKs are differentially regulated in neurons with alpha-synuclein-related inclusions and in neurons with abnormal tau deposits in DLB. Moreover, different kinase expression in brain stem and cortical LBs suggest a pathogenesis of brain stem and cortical LBs in LB diseases. Finally, no relationship has been observed between MAPK-P, p-38-P and SAPK/JNK-P expression and increased nuclear DNA vulnerability, as revealed with the method of in situ end-labeling of nuclear DNA fragmentation, and active, cleaved caspase-3 expression in neurons and glial cells in the substantia nigra in PD and DLB.
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PMID:Active, phosphorylation-dependent mitogen-activated protein kinase (MAPK/ERK), stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK), and p38 kinase expression in Parkinson's disease and Dementia with Lewy bodies. 1181 Apr 3

Tumor necrosis factor (TNF) is one of the most potent activators of nuclear transcription factor NF-kappaB, c-Jun N-terminal protein kinase (JNK), and apoptosis in a wide variety of cells. The biological effects of TNF are mediated through sequential interactions of various cytoplasmic proteins with intracellular domains of TNF receptors. Whether signal transducer and activator of transcription-1 (STAT1), which mediates interferon (IFN) signaling, also plays any role in the TNF-mediated activation of NF-kappaB, JNK, and apoptosis has not been established. Here, we report our investigation of the role of STAT1 in TNF signaling using STAT1-deficient U3A and STAT1-stably transfected U3A-PSG91 cells. IFNalpha inhibited the proliferation of STAT1-expressing U3A-PSG91 cells but had no effect on STAT1-negative U3A cells. TNF alone, even up to 10 nM, had no effect on the proliferation of either U3A-PSG91 or U3A cells. Irrespective of STAT1 status, TNF induced cytotoxic effects in the presence of cycloheximide (CHX) in both cell types. Additionally, TNF-induced caspase-3 and caspase-8 activation and TNF-induced PARP cleavage were unaffected by the presence or absence of STAT1. TNF activated NF-kappaB, consisting of p50 and p65, in both U3A and U3A-pSG91 cells in a dose- and time-dependent manner, but the degree and rate of activation were slightly lower in U3A cells, as were IkappaBalpha degradation and NF-kappaB-dependent reporter gene expression. STAT1 was, however, required for IFNalpha-mediated downregulation of TNF-induced NF-kappaB activation. TNF activated JNK in both cell types, but dose and time of exposure required for optimum activation differed slightly. Thus, overall our results indicate that STAT1 plays a minimal role in TNF-mediated cellular responses.
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PMID:Lack of requirement of STAT1 for activation of nuclear factor-kappaB, c-Jun NH2-terminal protein kinase, and apoptosis by tumor necrosis factor-alpha. 1183 5

The roles of the mitogen-activated protein (MAP) kinases extracellular signal-regulated kinases-1 and -2 (ERK-1/2) in fetal lung development have not been extensively characterized. To determine if ERK-1/2 signaling plays a role in fetal lung branching morphogenesis, U-0126, an inhibitor of the upstream kinase MAP ERK kinase (MEK), was added to fetal lung explants in vitro. Morphometry as measured by branching, area, perimeter, and complexity were significantly reduced in U-0126-treated lungs. At the same time, U-0126 treatment reduced ERK-1/2, slightly increased p38 kinase, but did not change c-Jun NH(2)-terminal kinase activities, indicating that U-0126 specifically inhibited the ERK-1/2 enzymes. These changes were associated with increased apoptosis as measured by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling and immunofluorescent labeling of anti-active caspase-3 in the mesenchyme of explants after U-0126 treatment compared with the control. Mitosis characterized by immunolocalization of proliferating cell nuclear antigen was found predominantly in the epithelium and was reduced in U-0126-treated explants. Thus U-0126 causes specific inhibition of ERK-1/2 signaling, diminished branching morphogenesis, characterized by increased mesenchymal apoptosis, and decreased epithelial proliferation in fetal lung explants.
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PMID:MEK-1/2 inhibition reduces branching morphogenesis and causes mesenchymal cell apoptosis in fetal rat lungs. 1183 29

Exposure to irradiation leads to detrimental changes in several cell types. In this study we assessed the changes induced in hippocampus by exposure of rats to whole body irradiation; the findings reveal that irradiation leads to apoptotic cell death in hippocampus, and as a consequence, long term potentiation in perforant path-granule cell synapses is markedly impaired. The evidence is consistent with the view that irradiation induced an increase in reactive oxygen species and that this leads to stimulation of the stress-activated protein kinase, JNK, and activation of the transcription factor, c-Jun. Consequent upon activation of JNK, a cascade of cell signaling events was stimulated that ultimately resulted in apoptosis, as suggested by parallel increases in cytochrome c translocation, caspase-3 activation, poly(ADP-ribose) polymerase cleavage, and terminal dUTP nick-end labeling staining. Treatment of rats with eicosapentaenoic acid inhibited the irradiation-induced increase in reactive oxygen species production and the subsequent cellular signaling events, suggesting that oxidative stress triggered apoptotic cell death in the hippocampus of rats exposed to irradiation. Significantly, when the compromise in cell viability induced by irradiation was prevented by eicosapentaenoic acid, long term potentiation was sustained in a manner similar to that in the sham-treated control group.
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PMID:Neuroprotective effect of eicosapentaenoic acid in hippocampus of rats exposed to gamma-irradiation. 1191 18


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