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)

Hippocampal kindling, a model of mesial temporal lobe epilepsy, is developed through repetitive stimulation of the hippocampus and leads to increased after-discharges as measured by EEG and an enduring seizure-prone state. Synthesis of new proteins is thought to form the basis for sustained seizure-induced physiological and/or pathological changes in synaptic reorganization and apoptotic/necrotic neuronal death. Here we examined the effect of kindling on stimulus-induced c-Jun N-terminal kinase (JNK) and p38 phosphorylation, events postulated to lie upstream of seizure-induced changes in gene transcription. We found that stimulus-induced phosphorylation of JNK, but not of p38, is significantly enhanced in kindled animals compared with their naive counterparts in the CA1 subregion of the hippocampus. Immunofluorescent staining confirmed this region-specific pattern of JNK activation and revealed that reactive astrocytes mediate this effect. Astrocyte proliferation and hypertrophy, as well as upregulation of vimentin protein levels, common markers of astrogliosis, were present after 4 d of kindling. Moreover, this reactive astrogliosis was associated with neuronal death as visualized with Fluoro-jade B and anti-active caspase-3 staining. Stimulus-induced phosphorylation of the JNK substrate paxillin was enhanced in kindled animals, but not that of c-Jun. Moreover, a pan-antibody against MAPK/CDK (mitogen-activated protein kinases/cyclin-dependent kinase) substrates indicated the presence of phosphorylated proteins in cytosolic, membrane, and nuclear fractions. The consequence of these phosphorylation events is not completely understood, but these findings suggest a selective astrocytic signaling response to aberrant synaptic activity, signaling that may modulate kindling progression and/or neuronal death.
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PMID:c-Jun N-terminal kinase activation responses induced by hippocampal kindling are mediated by reactive astrocytes. 1689 24

Clinical observations suggest that certain gut and dietary factors may transiently worsen symptoms in autism spectrum disorders (ASD), epilepsy and some inheritable metabolic disorders. Propionic acid (PPA) is a short chain fatty acid and an important intermediate of cellular metabolism. PPA is also a by-product of a subpopulation of human gut enterobacteria and is a common food preservative. We examined the behavioural, electrophysiological, neuropathological, and biochemical effects of treatment with PPA and related compounds in adult rats. Intraventricular infusions of PPA produced reversible repetitive dystonic behaviours, hyperactivity, turning behaviour, retropulsion, caudate spiking, and the progressive development of limbic kindled seizures, suggesting that this compound has central effects. Biochemical analyses of brain homogenates from PPA treated rats showed an increase in oxidative stress markers (e.g., lipid peroxidation and protein carbonylation) and glutathione S-transferase activity coupled with a decrease in glutathione and glutathione peroxidase activity. Neurohistological examinations of hippocampus and adjacent white matter (external capsule) of PPA treated rats revealed increased reactive astrogliosis (GFAP immunoreactivity) and activated microglia (CD68 immunoreactivity) suggestive of a neuroinflammatory process. This was coupled with a lack of cytotoxicity (cell counts, cleaved caspase 3' immunoreactivity), and an increase in phosphorylated CREB immunoreactivity. We propose that some types of autism may be partial forms of genetically inherited or acquired disorders involving altered PPA metabolism. Thus, intraventricular administration of PPA in rats may provide a means to model some aspects of human ASD in rats.
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PMID:Neurobiological effects of intraventricular propionic acid in rats: possible role of short chain fatty acids on the pathogenesis and characteristics of autism spectrum disorders. 1695 May 24

The aim of the study was to elucidate the relationship between various stages of amygdala kindling in rats and neuronal apoptosis. We used the unbiased method of RNase protection assay (RPA), measuring expression of several apoptosis-associated genes (for: caspase 1, caspase 2, caspase 3, FAS antigen, bax and bcl-x, bcl-2). The obtained results were also verified in situ in hippocampal slices, using the TUNEL method. The mRNA level of the investigated genes was estimated by densitometry and standardized according to the amount of L32 RNA. Only the expression of bcl-x L, caspase 2, caspase 3 and bax genes was measureable. In all experimental groups, the mRNA levels of bax and bcl-x genes were higher than mRNA of caspase-2 and caspase-3 genes. However, there were no statistically significant differences between the control and kindled animals. On the other hand, the TUNEL positive cells were found in total contralateral hippocampus of investigated animals belonging to C(0) (control group), C(3) (rats with 3rd stage of seizures) and c(5) (rats with 5th stage of seizures) groups. The number of TUNEL positive cells in the hippocampus was significantly higher in C(3) and C(5) groups (4.0 +/- 0.40 and 3.75 +/- 0.49) when compared to C(0) group (1.25 +/- 0.25). In conclusion, although apoptotic cells were found in situ in the hippocampus of kindled rats, RNase protection assay failed to measure any changes in mRNA levels of the chosen apoptotic genes. In our opinion, apoptotic cells might be too rare to detect any changes in gene expression. Therefore, the TUNEL procedure still remains the most favorable method of apoptotic cell death evaluation in the brain structures.
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PMID:Apoptotic markers in various stages of amygdala kindled seizures in rats. 1696 97

Menkes disease, a fatal neurodegenerative disorder resulting in seizures, hypotonia, and failure to thrive, is due to inherited loss-of-function mutations in the gene encoding a copper-transporting ATPase (Atp7a) on the X chromosome. Although affected patients exhibit signs and symptoms of copper deficiency, the mechanisms resulting in neurologic disease remain unknown. We recently discovered that Atp7a is required for the production of an NMDA receptor-dependent releasable copper pool within hippocampal neurons, a finding that suggests a role for copper in activity-dependent modulation of synaptic activity. In support of this hypothesis, we now demonstrate that copper chelation exacerbates NMDA-mediated excitotoxic cell death in primary hippocampal neurons, whereas the addition of copper is specifically protective and results in a significant decrease in cytoplasmic Ca(2+) levels after NMDA receptor activation. Consistent with the known neuroprotective effect of NMDA receptor nitrosylation, we show here that this protective effect of copper depends on endogenous nitric oxide production in hippocampal neurons, demonstrating in vivo links among neuroprotection, copper metabolism, and nitrosylation. Atp7a is required for these copper-dependent effects: Hippocampal neurons isolated from newborn Mo(br) mice reveal a marked sensitivity to endogenous glutamate-mediated NMDA receptor-dependent excitotoxicity in vitro, and mild hypoxic/ischemic insult to these mice in vivo results in significantly increased caspase 3 activation and neuronal injury. Taken together, these data reveal a unique connection between copper homeostasis and NMDA receptor activity that is of broad relevance to the processes of synaptic plasticity and excitotoxic cell death.
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PMID:Role of the Menkes copper-transporting ATPase in NMDA receptor-mediated neuronal toxicity. 1700 21

We have previously shown that the HSV-2 anti-apoptotic protein ICP10PK is delivered by the replication incompetent virus mutant DeltaRR and prevents kainic acid (KA)-induced epileptiform seizures and neuronal cell loss in the mouse and rat models of temporal lobe epilepsy. The present studies used DeltaRR and the ICP10PK deleted virus mutant DeltaPK to examine the mechanism of neuroprotection. DeltaRR-infected neuronal cells expressed a chimeric protein in which ICP10PK is fused in frame to LacZ (p175) while retaining ICP10PK kinase activity. DeltaPK-infected neuronal cells expressed a mutant ICP10 protein that is deleted in the PK domain and is kinase negative (p95). p175 and p95 were expressed in CA3 (86+/-3%) and CA1 (69+/-7%) cells from DeltaRR or DeltaPK-infected organotypic hippocampal cultures (OHC) and 80-85% of the ICP10 positive cells co-stained with antibody to beta(III) Tubulin (neuronal marker). DeltaRR, but not DeltaPK, inhibited KA-induced cell death and caspase-3 activation in CA3 neurons, an inhibition seen whether DeltaRR was delivered 2 days before or 2 days after KA administration (95% neuroprotection). Neuroprotection was associated with ERK and Akt activation and was abrogated by simultaneous treatment with the MEK (U0126) and PI3-K (LY294002) inhibitors. DeltaRR-mediated neuroprotection was associated with increased expression of the anti-apoptotic protein Bag-1 and decreased expression of the pro-apoptotic protein Bad. The surviving neurons retained normal synaptic function potentially related to increased expression of the transcription factor CREB. The data indicate that DeltaRR is a promising platform for neuroprotection from excitotoxic injury.
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PMID:The growth compromised HSV-2 mutant DeltaRR prevents kainic acid-induced apoptosis and loss of function in organotypic hippocampal cultures. 1702 Jul 50

The ketogenic diet (KD) is often effective for intractable epilepsy, but its antiepileptic mechanisms remain largely unknown. Within the cell death/survival pathway, Akt and its downstream protein Bad play an important role in kainic acid (KA)-induced cell death. Therefore, we investigated the effects of a KD on KA-induced changes in the Akt/Bad/14-3-3 signaling pathway by evaluating Akt, Bad, 14-3-3, and cleaved caspase-3 expression levels as well as their relative interactions. Our results showed that a KD did not affect the expression levels of Akt, Bad, Bcl-xL, Bax, and 14-3-3 but increased phospho-Akt [serine 473; p-Akt (Ser473)] and phospho-Bad [serine 136; p-Bad (Ser136)] expression levels as well as decreased cleaved caspase-3 levels following a KA-induced seizure in the hippocampus. Furthermore, we found that a KD increased the protein-protein interaction between 14-3-3 and p-Bad (Ser136), which might be phosphorylated by p-Akt (Ser473), and decreased interaction of Bad and Bcl-xL. These results suggest that a KD might protect, at least partially, the hippocampus from KA-induced cell death via inhibiting the dissociation of Bad from 14-3-3.
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PMID:Ketogenic diet protects the hippocampus from kainic acid toxicity by inhibiting the dissociation of bad from 14-3-3. 1705 67

Activation of the caspase-dependent cell death pathways has been shown in focal seizures, but whether this occurs in prolonged generalized seizures is not known. We investigated whether the initiator caspase in the extrinsic pathway, caspase-8, or the intrinsic pathway, caspase-9, is activated during the first 24 h following lithium-pilocarpine-induced status epilepticus, when neuronal death is maximal and widespread. The thymuses of rats given methamphetamine were used as positive controls for caspase-3-activated cellular apoptosis. Following methamphetamine treatment, caspase-9 but not caspase-8 was activated in thymocytes. However, 6 or 24 h following status epilepticus, none of 26 brain regions studied showed either caspase-8 or -9 activation by immunohistochemistry, western blotting and enzyme activity assays. Our results provide evidence against the activation of the extrinsic and intrinsic caspase pathways in generalized seizures, which produce morphologically necrotic neurons with internucleosomal DNA cleavage (DNA laddering), a programmed process. In contrast, there is increasing evidence that caspase-independent programmed mechanisms play a prominent role in seizure-induced neuronal death.
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PMID:Caspase-dependent programmed cell death pathways are not activated in generalized seizure-induced neuronal death. 1720 52

Kainic acid (KA) induced oxidative stress is associated with hippocampal cell death. Recent studies suggest that curcumin, a potent antioxidant, may provide protection for KA-induced oxidative stress. We investigated the effects of curcumin treatment on hippocampal reactive astrocytes in mice with KA-induced seizures. Eighteen hours after curcumin treatment, mice were treated with KA (30 mg/kg, i.p.), and then sacrificed after a further 48 h. Using cresyl violet staining and TUNEL analysis, histological evaluation revealed cell death in the KA-treated hippocampus. However, marked cell death was not observed in mice treated with curcumin. In addition, curcumin treatment reduced the KA-induced immunoreactivity of caspase-3. Similarly, immunoreactivity analyses indicated that KA causes upregulation of hippocampal GFAP, eNOS, and HO-1 levels, all of which were reduced in animals those received the curcumin treatment. Our findings indicate that curcumin is a potent inhibitor of reactive astrocyte expression and thus, prevents hippocampal cell death. These results also support its potential for use in the treatment of neurodegenerative diseases.
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PMID:Curcumin attenuates the kainic acid-induced hippocampal cell death in the mice. 1730 Aug 72

Status epilepticus results in preferential neuronal cell loss in the hippocampus. We evaluated the hypothesis that the repertoire of intracellular events in the vulnerable hippocampal CA3 subfield after induction of experimental temporal lobe status epilepticus entails upregulation of nitric oxide synthase II (NOS II), followed by the release of mitochondrial cytochrome c that triggers the cytosolic caspase-3 cascade, leading to apoptotic cell death. In Sprague-Dawley rats, significant and temporally correlated upregulation of NOS II (3-24h), but not NOS I or II expression, enhanced cytosolic translocation of cytochrome c (days 1 and 3), augmented activated caspase-3 in cytosol (days 1, 3 and 7) and DNA fragmentation (days 1, 3 and 7) was detected bilaterally in the hippocampal CA3 subfield after elicitation of sustained seizure activity by microinjection of kainic acid into the unilateral CA3 subfield. Application bilaterally into the hippocampal CA3 subfield of a selective NOS II inhibitor, S-methylisothiourea, significantly blunted these apoptotic events; a selective NOS I inhibitor, N(omega)-propyl-l-arginine or a potent NOS III inhibitor, N(5)-(1-iminoethyl)-l-ornithine was ineffective. We conclude that upregulation of NOS II contributes to apoptotic cell death in the hippocampal CA3 subfield via a cytochrome c/caspase-3 signaling cascade following the induction of experimental temporal lobe status epilepticus.
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PMID:Upregulation of nitric oxide synthase II contributes to apoptotic cell death in the hippocampal CA3 subfield via a cytochrome c/caspase-3 signaling cascade following induction of experimental temporal lobe status epilepticus in the rat. 1733 42

Clinical and experimental studies clearly demonstrate that prolonged seizures and status epilepticus induce neuronal cell death in the brain. Recent evidence suggests that induction of apoptosis contributes greatly to seizure-induced brain damage. We recently demonstrated that intrahippocampal delivery of botulinum neurotoxin E (BoNT/E) in the rat hippocampus is able to prevent neuronal loss, which occurs after kainic-acid-induced seizures. Here, we investigated the molecular mechanisms of BoNT/E-mediated neuroprotection. We found that intrahippocampal administration of BoNT/E prevents the upregulation of apoptotic proteins (phosphorylated c-Jun and cleaved caspase 3), which occurs in hippocampal neurones following kainic acid seizures. These results demonstrate that the neuroprotective action of BoNT/E on seizure-injured hippocampal neurons involves the blockade of well-characterized apoptotic pathways.
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PMID:BoNT/E prevents seizure-induced activation of caspase 3 in the rat hippocampus. 1741 60


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