Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0027819 (neuroblastoma)
 27,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Oxidative stress may be an important factor in several pathological brain conditions. A contributing factor in many such conditions is excessive glutamate release, and subsequent glutamatergic neuronal stimulation, that causes increased production of reactive oxygen species (ROS), oxidative stress, excitotoxicity and neuronal damage. Glutamate release is also associated with illnesses such as Alzheimer's disease, stroke, and brain injury. Glutamate may interact with an environmental toxin, lead, and this interaction may result in neuronal damage. Glutamate-induced ROS production is greatly amplified by lead in cultured neuronal cells. Alterations in protein kinase C (PKC) activity seem to be important both for glutamate-induced ROS production, and for the amplification of glutamate-induced ROS production by lead. It is possible that the neurotoxic effects of lead are amplified through glutamate-induced neuronal excitation. Cholinergic stimulation can also trigger ROS production in neuronal cells. PKC seems to play a key-role also in cholinergic-induced ROS production superoxide anion being the primary reactive oxygen species. There seems to be a close relationship between the responses of cholinergic muscarinic and glutamatergic receptors because glutamate receptor antagonists inhibit cholinergic-induced activation of human neuroblastoma cells. Glutamatergic neuronal stimulation may be a common final pathway in several brain conditions in which oxidative stress and ensuing excitotoxicity plays a role.
 ...
PMID:Glutamate-stimulated ROS production in neuronal cultures: interactions with lead and the cholinergic system. 974 27

Oxidative stress is considered an important pathophysiological mechanism contributing to promote cell death in a broad variety of diseases including cardiovascular and neurodegenerative disorders. The so-called scavestrogens J811 and J861, structurally derived from 17alpha-estradiol, are potent radical scavengers and inhibitors of iron-induced cell damage in vitro. In this study the potential cytoprotective effects of the scavestrogens J811 and J861 against Fenton reagent-induced cell damage (50 microM FeSO4 plus 200 microM H2O2) were compared with those of 17alpha- and 17beta-estradiol. Cell viability studies using Trypan blue staining showed that estradiols and scavestrogens at concentrations ranging from 0.1 to 10 microM are able to protect IMR 32 neuroblastoma cells from Fenton-mediated death. In addition, these compounds decreased lipid peroxidation measured as thiobarbituric acid reactive substances and renormalize oxidative stress-increased intracellular glutathione levels. When given 6 h after the toxic stimulus, J811 and J861 rescued 60% of cells, whereas 17alpha- and 17beta-estradiol were ineffective. These results suggest that the scavestrogens J811 and J861 are powerful antioxidants capable of interfering with radical-mediated cell death in diseases known to be aggravated by reactive oxygen species. Such compounds may be useful in the development of novel treatments for stroke or neurodegenerative disorders.
 ...
PMID:Scavestrogens protect IMR 32 cells from oxidative stress-induced cell death. 977 99

We have attempted to elucidate the mechanism of apoptotic cell death induced by hypoxia (very low oxygen conditions) in neuronal cells. Human neuroblastoma SK-N-MC cells under hypoxic conditions resulted in apoptosis in a time-dependent manner estimated by DNA fragmentation assay and nuclear morphology stained with fluorescent chromatin dye. Pretreatment with Z-Asp-CH2-DCB, a caspase inhibitor, suppressed the DNA ladder in response to hypoxia in a concentration-dependent manner. An increase in caspase-3-like protease (DEVDase) activity was observed during apoptosis, but no caspase-1 activity (YVADase) was detected. To confirm the involvement of caspase-3 during apoptosis, Western blot analysis was performed using anti-caspase-3 antibody. The 20- and 17-kDa proteins, corresponding to the active products of caspase-3, were generated in hypoxia-challenged lysates in which processing of the full length form of caspase-3 was evident. With a time course similar to this caspase-3 activation, hypoxic stress caused the cleavage of PARP, yielding an 85-kDa fragment typical of caspase activity. In addition, caspase-2 was also activated by hypoxia, and the stress elicited the release of cytochrome c into the cytosol during apoptosis. These results suggest that caspase activation and cytochrome c release play roles in hypoxia-induced neuronal apoptosis.
 ...
PMID:Hypoxia induces apoptosis in human neuroblastoma SK-N-MC cells by caspase activation accompanying cytochrome c release from mitochondria. 984

Recent data suggesting complex I dysfunction in Parkinson's disease (PD) arises from mitochondrial DNA (mtDNA) mutation does not conclusively answer whether the responsible genetic lesion is inherited (primary) or somatic (secondary). To address this question, we identified a family in which multiple members over three generations are affected with PD through exclusively maternal lines. Cytoplasmic hybrids (cybrids) were created for 15 family members over two generations by transferring each individual's mtDNA to mtDNA-depleted human neuroblastoma cells. Eight of the 15 cybrid lines contained mtDNA obtained from maternally descended family members and seven contained mtDNA from paternally descended family members. After 6 weeks of culture, cybrid cell lines were assayed for complex I activity and oxidative stress, and mitochondrial morphology was analyzed by electron microscopy. Compared with the cybrid lines containing mtDNA from paternal descendants, cybrid lines containing mtDNA from maternal descendants had lower complex I activity, increased reactive oxygen species production, increased radical scavenging enzyme activities, and more abnormal mitochondrial morphologic features. These findings were present in cybrid lines containing mtDNA from maternal descendants with PD as well as in currently asymptomatic young maternal descendants, and support a precedent for inherited mtDNA mutation in some persons with PD.
 ...
PMID:Matrilineal inheritance of complex I dysfunction in a multigenerational Parkinson's disease family. 985 31

Treatment of human neuroblastoma SH-SY5Y cells with 1 mM 1-methyl-4-phenylpyridinium (MPP+) for 3 days induced production of reactive oxygen species (ROS), followed by caspase-3 activation, cleavage of poly(ADP-ribose) polymerase (PARP), and apoptotic cell death with DNA fragmentation and characteristic morphological changes (condensed chromatin and fragmented nuclei). Simultaneous treatment with 1 mM talipexole slightly inhibited the MPP+-induced ROS production and apoptotic cell death. In contrast, pretreatment with 1 mM talipexole for 4 days markedly protected the cells against MPP+-induced apoptosis. However, this protective effect might not be mediated by dopamine receptors. The talipexole pretreatment induced an increase in antiapoptotic Bcl-2 protein level but had no effect on levels of proapoptotic Bax, Bak, and Bad. It also inhibited MPP+-induced ROS production, p53 expression, and cleavages of caspase-3 and PARP. Similarly, pramipexole pretreatment increased Bcl-2 and inhibited MPP+-induced apoptosis. Although pretreatment with bromocriptine also had a protective effect against MPP+-induced apoptosis, it had no effect on the protein levels of Bcl-2 family members. On the other hand, N6,2'-O-dibutyryl cAMP or calphostin C induced a decreased Bcl-2 level and enhanced MPP+-induced cell death. These results suggest that talipexole has dual actions: (1) it directly scavenges ROS, affording slight protection against MPP+-induced apoptosis, and (2) it induces Bcl-2 expression, thereby affording more potent protection, if it is administrated before MPP+. Pramipexole has similar effects, whereas bromocriptine seems to exhibit the former but not the latter effect.
 ...
PMID:Protective effects of the antiparkinsonian drugs talipexole and pramipexole against 1-methyl-4-phenylpyridinium-induced apoptotic death in human neuroblastoma SH-SY5Y cells. 985 33

Non-enzymatic glycation of proteins with reducing sugars and subsequent transition metal catalysed oxidations leads to the formation of protein bound "advanced glycation endproducts" (AGEs). They accumulate on long-lived proteins and are for example structural components of the beta-amyloid plaques in Alzheimer's disease. Since the oxidation of glycated proteins as well as the interaction of AGEs with cell surface receptors produces superoxide radicals, it was tested in BHK 21 hamster fibroblast cells and SH-SY5Y human neuroblastoma cells if AGEs can exert cytotoxic effects on cells. Cell viability was assessed with three independent tests: MTT-assay (activity of the mitochondrial respiratory chain), lactate dehydrogenase assay (release of cytoplasmatic enzymes, membrane integrity) and Neutral Red assay (active uptake of a hydrophilic dye). Two model AGEs, chicken egg albumin-AGE and BSA-AGE, both caused significant cell death in a dose-dependent manner. The cytotoxic effects of AGEs could be attenuated by alpha-ketoglutarate and pyruvate, by antioxidants such as thioctic acid and N-acetylcysteine, and by aminoguanidine, an inhibitor of nitric oxide synthase. This suggests that reactive oxygen species as well as reactive nitrogen species contribute to AGE mediated cytotoxicity. Since AGEs accumulate on beta-amyloid plaques in AD over time, they may additionally contribute to oxidative stress, cell damage, functional loss and even neuronal cell death in the Alzheimer's disease brain.
 ...
PMID:Cytotoxicity of advanced glycation endproducts is mediated by oxidative stress. 986 32

Neurodegenerative disorders are characterized by a massive loss of nerve cells. The neuronal cell death is accompanied by an increased cholesterol release and conversion of cholesterol into the polar metabolite, 24-hydroxycholesterol (24-OH-Chol), appears to be an important mechanism in the central nervous system for eliminating cholesterol from the brain. We tested the influence of 24-OH-Chol on SH-SY5Y human neuroblastoma cells by recording cell morphology, Trypan blue exclusion, LDH-release into the culture medium, intracellular calcium and reactive oxygen species (ROS). The exposure of SH-SY5Y human neuroblastoma cells to 50 microM 24-OH-Chol led to a 90% loss in cell viability within 30 h, the LDH-release into the medium increased rapidly after 24 h, and after 24 to 30 h we found an elevation in intracellular calcium. These results show that, in a physiological concentration range, 24-OH-Chol damages neuronal cells, thus we speculate that this oxysterol may be involved in the etiology of neurodegenerative disease.
 ...
PMID:The neurotoxic effect of 24-hydroxycholesterol on SH-SY5Y human neuroblastoma cells. 991 53

In order to perform in vitro testing of esterase inhibition caused by organophosphorous (OP) protoxicants, simple, reliable methods are needed to convert protoxicants to their esterase-inhibiting forms. Incubation of parathion or chlorpyrifos with 0.05% bromine solution or uninduced rat liver microsomes (RLM) resulted in production of the corresponding oxygen analogs of these OP compounds and markedly increased esterase inhibition in SH-SY5Y human neuroblastoma cells. Neither activation system affected cell viability or the activity of AChE or NTE in the absence of OP compounds. Although parathion and chlorpyrifos were activated by RLM, bromine activation required fewer steps and produced more esterase inhibition for a given concentration of chlorpyrifos. However, RLM activation of OP protoxicants produced metabolites other than oxygen analogs and may, therefore, be more relevant as a surrogate for OP biotransformation in vivo. This methodology makes the use of intact cells for in vitro testing of esterase inhibition caused by protoxicant organophosphate compounds a viable alternative to in vivo tests.
 ...
PMID:Comparison of two in vitro activation systems for protoxicant organophosphorous esterase inhibitors. 1004 49

Regulatory interactions among individual receptor-coupled signal transduction systems are critically important for establishing cellular responses in the face of multiple stimuli. In this study, potential regulatory interactions between signal transduction systems activated by growth factor receptors and by G-protein-coupled receptors were examined using human neuroblastoma SH-SY5Y cells which express endogenous epidermal growth factor (EGF) and muscarinic M3 receptors. Activation of muscarinic receptors with carbachol was found to inhibit EGF-induced signaling, including tyrosine phosphorylation of the adaptor protein Cbl and of the EGF receptor, and complex formation between Shc proteins and the EGF receptor and Grb2. Protein kinase C, which is activated by muscarinic M3 receptors, mediated this inhibitory cross-talk. Activation of EGF receptors was found to inhibit muscarinic receptor-induced tyrosine phosphorylation of focal adhesion kinase and paxillin. Reactive oxygen species, which are formed as components of the EGF signaling cascade, mediated this inhibitory cross-talk. These mutual inhibitory interactions demonstrate novel mechanisms for neuronal integration of multiple signals generated by activation of receptors by neurotransmitters and growth factors.
 ...
PMID:Muscarinic M3 and epidermal growth factor receptors activate mutually inhibitory signaling cascades in human neuroblastoma SH-SY5Y cells. 1004 86

A genetic defect in complex I of the mitochondrial electron transport chain (ETC) is implicated in the etiology of Parkinson's disease (PD), and has been studied in hybrid mitochondrial transgene cells based on the SH-SY5Y neuroblastoma. We sought to characterize further the mechanisms and time course of cell death in cultures of human SH-SY5Y neuroblastoma cells exposed to the ETC complex I inhibitor methylpyridinium ion (MPP+). We verify previous reports that apoptosis occurs after MPP+ exposure in SH-SY5Y cells. Nuclear pyknosis, the end stage of apoptosis, is evident after 18-hr exposure to 5 mM MPP+ and reversible until 10 hr, providing a temporal window within which to look for molecular and physiological correlates of MPP+-induced apoptosis. We then looked for mitochondrial correlates of MPP+ induced apoptosis in SH-SY5Y cells. Using flow cytometry, we found that MPP+ -induced increased reactive oxygen species (ROS) and lactate production consistent with inhibition of the ETC. Rho(o) cells, lacking a functional ETC, showed no ROS production, compensatory lactate production or apoptosis after exposure to MPP+. Finally, we show a collapse in ROS production and mitochondrial potential that is temporally correlated with irreversibility of MPP+ -induced apoptosis.
 ...
PMID:Characterization and time course of MPP+ -induced apoptosis in human SH-SY5Y neuroblastoma cells. 1008 84


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>