benzofurans has been researched along with Neuroblastoma* in 30 studies
1 review(s) available for benzofurans and Neuroblastoma
1 trial(s) available for benzofurans and Neuroblastoma
29 other study(ies) available for benzofurans and Neuroblastoma
| Article | Year |
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Dihydroactinidiolide regulates Nrf2/HO-1 expression and inhibits caspase-3/Bax pathway to protect SH-SY5Y human neuroblastoma cells from oxidative stress induced neuronal apoptosis.
Alzheimer's disease (AD) etiology has been studied for a long time and it is found to be multifaceted involving the accumulation of amyloid β and tau protein. Oxidative stress is an early event in AD associated neurodegeneration provoking neuronal death through mitochondrial dysfunction and activation of caspase-3. Therefore we tested the efficacy of dihydroactinidiolide (DHAc), a monoterpene lactone against the oxidative load involved in AD like pathological conditions induced by sodium dithionite, glutamate, amyloid β and colchicine in SH-SY5Y cells. Some of the indicators of neurotoxicity like acetylcholinesterase activity, intracellular reactive oxygen species (ROS), nitrite content, lipid peroxidation, protein carbonylation, nuclear and membrane damage were found to be significantly high in the toxicant treated cells when compared to the control cells while DHAc pretreatment significantly restored the toxicant induced neuronal damage signatures. Caspase-3 activity was found to be increased in the toxicant treated cells while DHAc significantly reduced it. Western blotting and RT-PCR revealed that DHAc significantly increased anti-apoptotic Bcl-2 expression and mRNA levels of Nrf2 and HO-1. Therefore DHAc was found to protect SH-SY5Y cells from neurotoxicant induced oxidative stress and apoptosis by regulating cellular antioxidant defenses and apoptosis related genes. Topics: Apoptosis; bcl-2-Associated X Protein; Benzofurans; Caspase 3; Caspase Inhibitors; Cell Line, Tumor; Dose-Response Relationship, Drug; Heme Oxygenase-1; Humans; Neuroblastoma; Neurons; Neuroprotective Agents; NF-E2-Related Factor 2; Oxidative Stress | 2021 |
Neuroprotective effects of Senkyunolide I against glutamate-induced cells death by attenuating JNK/caspase-3 activation and apoptosis.
Glutamate-induced neurotoxicity is one of the most important pathogenic mechanisms in neurological diseases and is widely used as an in vitro model for ischemic stroke. Senkyunolide I (SEI), an active constituent derived from traditional Chinese medicine Ligusticum chuanxiong Hort. and Angelica sinensis (Oliv.) Diels, has been shown to have beneficial effects against focal cerebral ischemia-reperfusion in rats. However, the mechanisms underlying SEI-mediated neuroprotection remain not well understood. Thus, we explored the influence of SEI in glutamate-mediated injury to mouse neuroblastoma (Neuro2a) cells and determined the mechanisms involved. Neuro2a cells were treated with SEI under exposure to glutamate for 24 h. Cell viability was assessed by using WST-1 reagents, and apoptosis was evaluated using Annexin V-FITC and a PI double staining kit. The protein expression levels of p-AKT, AKT, p-GSK3β, GSK3β, p-p38, p38, p-ERK, ERK, p-JNK, JNK, Bcl-2, Bax, Bcl-xl, p-Bad, Bad, p53, and cleaved caspase-3 were determined by Western blot analysis. Glutamate significantly decreased cell viability and elevated the level of apoptosis. Treatment with SEI reversed those effects. Furthermore, the expression of p-JNK/JNK and cleaved caspase-3 were also reduced after treatment with SEI. Our findings demonstrate that SEI protected Neuro2a cells against glutamate toxicity by regulating JNK/caspase-3 pathway and apoptosis. Thus, SEI maybe a promising candidate for neuroprotection. Topics: Animals; Apoptosis; Benzofurans; Brain Ischemia; Caspase 3; Cell Death; Cell Survival; Cells, Cultured; Glutamic Acid; MAP Kinase Signaling System; Mice; Neuroblastoma; Neuroprotection; Neuroprotective Agents; Reperfusion Injury; Signal Transduction | 2021 |
Antitumor Effect of Burchellin Derivatives Against Neuroblastoma.
Neuroblastoma is one of the most commonly encountered malignant solid tumors in the pediatric age group. We examined the antitumor effects of five burchellin derivatives against human neuroblastoma cell lines.. We evaluated cytotoxicity by the MTT assay for four human neuroblastoma and two normal cell lines. We also performed analysis of the apoptotic induction effect by flow cytometry, and examined the expression levels of apoptosis- and cell growth-related proteins by western blot analysis.. We found that one of the burchellin derivatives (compound. Compound Topics: Antineoplastic Agents, Phytogenic; Benzofurans; Cell Line, Tumor; Drug Screening Assays, Antitumor; Drugs, Chinese Herbal; Humans; Neuroblastoma | 2018 |
Gnetin C, a resveratrol dimer, reduces amyloid-β 1-42 (Aβ42) production and ameliorates Aβ42-lowered cell viability in cultured SH-SY5Y human neuroblastoma cells.
Accumulation and oligomerization of amyloid-beta (Aβ) peptides have been known to be a potent cause of neurodegenerative diseases such as Alzheimer's disease (AD). To expand the possibilities of preventing AD, we investigated the effects of resveratrol dimers, gnetin C and ε-viniferin, on Aβ 1-42 (Aβ42) production and the reduced cell viability observed after Aβ42 treatment (monomers, 10 μM) in cultured SH-SY5Y human neuroblastoma cells. Among them, addition of gnetin C (20 μM) into the media reduced Aβ42 production most efficiently. Gnetin C suppressed the expression of β-site amyloid precursor protein-cleaving enzyme-1 (BACE1, β-secretase). Furthermore, gnetin C ameliorated the Aβ42-reduced cell viability most significantly. Concomitantly, gnetin C reduced intracellular Aβ oligomers (ca. 15 and 130 kDa) and elevated both levels of intracellular and extracellular Aβ monomers. Under the treatment with or without Aβ42, gnetin C upregulated the expression of matrix metalloproteinase-14 (MMP-14) which is assumed to be an Aβ-decomposing enzyme. Gnetin C may thereby prevent Aβ toxicity by suppressing BACE1 and enhancing MMP-14, together with reducing both internalization and oligomerization of exogenous Aβ monomers. The use of gnetin C may lead to the prevention of Aβ-mediated diseases, particularly AD. Topics: Alzheimer Disease; Amyloid beta-Peptides; Benzofurans; Cell Line, Tumor; Cell Survival; Gene Expression Regulation, Neoplastic; Humans; Neoplasm Proteins; Neuroblastoma; Peptide Fragments; Resveratrol; Stilbenes | 2018 |
dl-3-n-Butylphthalide attenuation of methamphetamine-induced neurotoxicity in SH-SY5Y neuroblastoma cells.
Methamphetamine (Meth) abuse causes neural injury in the brain. There are no efficacious therapies available to treat Meth-induce neural injury. The present study intended to test the therapeutic potential of dl-3-n-butylphthalide (NBP), a chemical compound extracted originally from the seeds of Chinese Celery, in the amelioration and prevention of Meth-induced neural injury.. Experiments were carried out on SH-SY5Y cells. Neuronal injury and apoptotic cell death were detected by MTT assay and analysis of nuclear morphology. Intracellular reactive oxygen species (ROS) was evaluated by dichloro-dihydro-fluorescein diacetate (DCFH-DA) assay and protein expression levels of the apoptosis-related cleaved caspase-3, bcl2 and Bax were determined by western blotting.. Treatment of SH-SY5Y cells with Meth induced cell injury and apoptosis. NBP attenuated Meth-associated cell injury and apoptosis via blockage of Meth-mediated upregulation of intracellular ROS production and inhibition of Meth-induced decrease of cleaved caspase-3/caspase-3 and Bcl-2/Bax ratios.. The results presented in this study indicate that NBP may have therapeutic benefits in the treatment of Meth-induced neuronal injury in the central nervous system. Topics: Benzofurans; Cell Line, Tumor; Humans; Methamphetamine; Neuroblastoma; Neurotoxicity Syndromes; Reactive Oxygen Species; Signal Transduction | 2016 |
Modulating autophagy affects neuroamyloidogenesis in an in vitro ischemic stroke model.
To explore the effects of modulating autophagy on neuroamyloidogenesis in an ischemic stroke model of cultured neuroblastoma 2a (N2a)/Amyloid precursor protein (APP)695 cells.. The ischemic stroke model of N2a/APP695 cells was made by 6h oxygen-glucose deprivation/12h reperfusion (OGDR). Drug administration of 3-methyladenine (3-MA), rapamycin or dl-3-n-butylphthalide (NBP) was started at the beginning of the OGDR and lasted until the end of reperfusion, in order to explore their effects on N2a/APP695 cells under OGDR conditions. Then the cells were incubated in the drug-free and full culture medium under normoxic conditions for 12h. Cell viability and injury were investigated. The key proteins of nuclear factor kappa B (NF-κB) pathway and a key component of autophagy Beclin 1 were detected by Western blotting; immunofluorescence double-staining of amyloid-β (Aβ)1-42 with Beclin 1 was performed to investigate their cellular co-localization relationship; β-secretase and γ-secretase activity assay and Aβ1-42 enzyme-linked immunosorbent assay were performed to investigate the amyloidogenesis.. The results showed that, OGDR enhanced cell injury, autophagy activity, neuroinflammation and Aβ generation in N2a/APP695 cells; down-regulating autophagy by 3-MA and NBP increased cell viability, decreased lactate dehydrogenase (LDH) production, inhibited the activation of NF-κB pathway, suppressed β- and γ-secretase activities and Aβ generation; while up-regulating autophagy by rapamycin got the opposite results; immunofluorescence double-staining results showed elevated Aβ1-42(+) signal was co-localized with Beclin 1(+) signal.. Our data suggested that down-regulating autophagy may inhibit ischemia-induced neuroamyloidogenesis via suppressing the activation of NF-κB pathway. This study might help us to find a new therapeutic strategy to prevent brain ischemic damage and depress the risk of post-stroke dementia. Topics: Adenine; Amyloid beta-Protein Precursor; Amyloid Precursor Protein Secretases; Animals; Autophagy; Benzofurans; Brain Ischemia; Cell Survival; Mice; Neuroblastoma; Sirolimus; Stroke; Tumor Cells, Cultured | 2014 |
Sulfuretin inhibits 6-hydroxydopamine-induced neuronal cell death via reactive oxygen species-dependent mechanisms in human neuroblastoma SH-SY5Y cells.
Sulfuretin, a potent anti-oxidant, has been thought to provide health benefits by decreasing the risk of oxidative stress-related diseases. In this study, we investigated the mechanisms of sulfuretin protection of neuronal cells from cell death induced by the Parkinson's disease (PD)-related neurotoxin 6-hydroxydopamine (6-OHDA). We examined whether sulfuretin acts as an anti-oxidant to reduce oxidative stress and mitochondrial-mediated apoptotic cascade events in 6-OHDA-induced neurotoxicity in SH-SY5Y cells. We also investigated whether sulfuretin specifically acts by inhibiting phosphorylation of mitogen-activated protein kinase (MAPK), phosphatidylinositol 3-kinase (PI3K)/Akt, and glycogen synthase kinase-3beta (GSK-3β) as well as activation of the nuclear factor-kappa B (NF-κB) pathway. Sulfuretin significantly inhibited neuronal cell death, neurotoxicity, apoptosis, and reactive oxygen species (ROS) production. Sulfuretin also strikingly attenuated 6-OHDA-induced mitochondrial dysfunction. Moreover, sulfuretin significantly attenuated 6-OHDA-induced phosphorylation of c-Jun N-terminal kinase (JNK), p38, extracellular signal-regulated kinase 1/2 (ERK 1/2) MAPKs, PI3K/Akt, and GSK-3β. Eventually, sulfuretin inhibited 6-OHDA-induced NF-κB translocation to the nucleus induced by 6-OHDA. The results of the current study provide the first evidence that sulfuretin protects SH-SY5Y cells against 6-OHDA-induced neuronal cell death, possibly through inhibition of phosphorylation of MAPK, PI3K/Akt, and GSK-3β, which leads to mitochondrial protection, NF-κB modulations and subsequent suppression of apoptosis via ROS-dependent pathways. Thus, we conclude that sulfuretin may have a potential role for neuroprotection and, therefore, may be used as a therapeutic agent for PD. Topics: Benzofurans; Catalase; Cell Death; Cell Line, Tumor; Flavonoids; Glutathione; Humans; In Situ Nick-End Labeling; Neuroblastoma; Neurons; Oxidopamine; Reactive Oxygen Species; Superoxide Dismutase | 2014 |
l-3-n-Butylphthalide attenuates β-amyloid-induced toxicity in neuroblastoma SH-SY5Y cells through regulating mitochondrion-mediated apoptosis and MAPK signaling.
Alzheimer's disease (AD) is a progressive neurodegenerative disease. Amyloid-β protein (Aβ), the hallmark of AD, invokes a cascade of mitochondrial dysfunction and eventually leads to neuronal death. l-3-n-Butylphthalide (l-NBP) has shown the potent neuroprotective effects in stroke and AD animal models. The present study is to evaluate the neuroprotective effect of l-NBP on Aβ25-35-induced neuronal injury and the possible mechanism in the human neuroblastoma SH-SY5Y cells. Our results showed that l-NBP significantly attenuated Aβ25-35-induced cell death and reduced neuronal apoptosis. l-NBP significantly inhibited Aβ25-35-induced mitochondrial dysfunction, including mitochondrial membrane potential reduction, and reactive oxygen species production. Furthermore, l-NBP could partially reverse the elevations of Aβ25-35-induced active caspase-3, caspase-9, and cytochrome c expressions, and the downregulation of anti-apoptosis protein Bcl-2. Moreover, l-NBP markedly inhibited the activations of p38 mitogen-activated protein kinase and c-Jun N-terminal kinase/stress-activated protein kinase signaling pathway. These results demonstrated that l-NBP was capable of protecting neuronal cells from Aβ25-35-induced toxicity through a mitochondrial-dependent apoptotic pathway. Thus, l-NBP shows promising candidate of multi-target neuronal protective agent for the treatment of AD. Topics: Alzheimer Disease; Amyloid beta-Peptides; Animals; Apoptosis; Benzofurans; Caspase 3; Caspase 9; Humans; MAP Kinase Signaling System; Membrane Potential, Mitochondrial; Mitochondria; Molecular Structure; Neuroblastoma; Neuroprotective Agents; p38 Mitogen-Activated Protein Kinases; Peptide Fragments; Reactive Oxygen Species; Signal Transduction | 2014 |
RuvBL2 is involved in histone deacetylase inhibitor PCI-24781-induced cell death in SK-N-DZ neuroblastoma cells.
Neuroblastoma is the second most common solid tumor diagnosed during infancy. The survival rate among children with high-risk neuroblastoma is less than 40%, highlighting the urgent needs for new treatment strategies. PCI-24781 is a novel hydroxamic acid-based histone deacetylase (HDAC) inhibitor that has high efficacy and safety for cancer treatment. However, the underlying mechanisms of PCI-24781 are not clearly elucidated in neuroblastoma cells. In the present study, we demonstrated that PCI-24781 treatment significantly inhibited tumor growth at very low doses in neuroblastoma cells SK-N-DZ, not in normal cell line HS-68. However, PCI-24781 caused the accumulation of acetylated histone H3 both in SK-N-DZ and HS-68 cell line. Treatment of SK-N-DZ with PCI-24781 also induced cell cycle arrest in G2/M phase and activated apoptosis signaling pathways via the up-regulation of DR4, p21, p53 and caspase 3. Further proteomic analysis revealed differential protein expression profiles between non-treated and PCI-24781 treated SK-N-DZ cells. Totally 42 differentially expressed proteins were identified by MALDI-TOF MS system. Western blotting confirmed the expression level of five candidate proteins including prohibitin, hHR23a, RuvBL2, TRAP1 and PDCD6IP. Selective knockdown of RuvBL2 rescued cells from PCI-24781-induced cell death, implying that RuvBL2 might play an important role in anti-tumor activity of PCI-24781 in SK-N-DZ cells. The present results provide a new insight into the potential mechanism of PCI-24781 in SK-N-DZ cell line. Topics: Acetylation; Apoptosis; ATPases Associated with Diverse Cellular Activities; Benzofurans; Blotting, Western; Carrier Proteins; Cell Line, Tumor; DNA Helicases; G2 Phase Cell Cycle Checkpoints; Histone Deacetylase Inhibitors; Histones; Humans; Hydroxamic Acids; Male; Mitosis; Models, Biological; Neoplasm Proteins; Neuroblastoma; Proteomics; Reproducibility of Results; Signal Transduction | 2013 |
Moracenin D from Mori Cortex radicis protects SH-SY5Y cells against dopamine-induced cell death by regulating nurr1 and α-synuclein expression.
In our efforts to find neuroprotective materials of plant origin, several compounds were isolated from Mori Cortex Radicis. The protective effect against dopamine-induced cell death was examined, and the subsequent effects on the levels of expression of Parkinson's disease-associated nurr1 and α-synuclein were evaluated in a dopamine-induced system. Five compounds were isolated and moracenin D protected cell death against dopamine-induction in human neuroblastoma SH-SY5Y cells. The effects of moracenin D on the levels of mRNA and protein expression of nurr1 and α-synuclein were subsequently examined using reverse transcription-polymerase chain reaction (RT-PCR) and western blot analysis. Treatment with moracenin D resulted in an up-regulation of nurr1 mRNA levels and a down-regulation of α-synuclein mRNA levels. Additionally, the α-synuclein protein expression was decreased in accordance with an increase in nurr1 protein expression. These results demonstrate that the protective effects of moracenin D were presumably due to the correlative effects on the up-regulation of nurr1 and down-regulation of α-synuclein expressions against dopamine induction. Therefore, moracenin D can be considered as a candidate for therapy for Parkinson's disease. Topics: alpha-Synuclein; Benzofurans; Blotting, Western; Cell Death; Cell Line, Tumor; Cell Survival; Dopamine; Flavonoids; Gene Expression Regulation, Neoplastic; Humans; Methanol; Moraceae; Neuroblastoma; Neuroprotective Agents; Nuclear Receptor Subfamily 4, Group A, Member 2; Plant Extracts; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger | 2012 |
L-3-n-butylphthalide reduces tau phosphorylation and improves cognitive deficits in AβPP/PS1-Alzheimer's transgenic mice.
L-3-n-butylphthalide (L-NBP), an extract from seeds of Apium graveolens Linn (Chinese celery), has been shown to have neuroprotective effects on cerebral ischemic, vascular dementia and amyloid-β (Aβ)-induced animal models by inhibiting oxidative injury, neuronal apoptosis and glial activation, regulating amyloid-β protein precursor (AβPP) processing and reducing Aβ generation. The aim of the present study was to examine the effect of L-NBP on learning and memory in AβPP and presenilin 1 (PS1) double-transgenic AD mouse model (AβPP/PS1) and the mechanisms of L-NBP in reducing Aβ accumulation and tau phosphorylation. Twelve-month old AβPP/PS1 mice were given 15 mg/kg L-NBP by oral gavage for 3 months. L-NBP treatment significantly improved the spatial learning and memory deficits compared to the vehicle-treated AβPP/PS1 mice, whereas L-NBP treatment had no effect on cerebral Aβ plaque deposition and Aβ levels in brain homogenates. However, we found an L-NBP-induced reduction of tau hyperphosphorylation at Ser199, Thr205, Ser396, and Ser404 sites in AβPP/PS1 mice. Additionally, the expressions of cyclin-dependent kinase and glycogen synthase kinase 3β, the most important kinases involved in tau phosphorylation, were markedly decreased by L-NBP treatment. The effects of L-NBP on decreasing tau phosphorylation and kinases activations were further confirmed in neuroblastoma SK-N-SH cells overexpressing wild-type human AβPP695 (SK-N-SH AβPPwt). L-NBP shows promising candidate of multi-target neuronal protective agent for the treatment of Alzheimer's disease. Topics: Alzheimer Disease; Amyloid beta-Peptides; Amyloid beta-Protein Precursor; Analysis of Variance; Animals; Benzofurans; Brain; Cell Line, Tumor; Cognition Disorders; Cyclin-Dependent Kinase 5; Disease Models, Animal; Gene Expression Regulation; Glycogen Synthase Kinase 3; Glycogen Synthase Kinase 3 beta; Humans; Male; Maze Learning; Mice; Mice, Transgenic; Neuroblastoma; Neuroprotective Agents; Phosphorylation; Presenilin-1; Reaction Time; Spatial Behavior; tau Proteins; Time Factors | 2012 |
L-3-n-butyl-phthalide alleviates hydrogen peroxide-induced apoptosis by PKC pathway in human neuroblastoma SK-N-SH cells.
Alzheimer's disease (AD) is the most common form of dementia. Oxidative stress is one of the earliest events in the neurological and pathological changes of AD. L-3-n-butyl-phthalide (L-NBP), an anti-cerebral ischemia agent, has been shown a potential in AD treatment. In this study, we investigated the neuroprotective effect of L-NBP on hydrogen peroxide (H₂O₂)-induced apoptosis in human neuroblastoma SK-N-SH cells. H₂O₂ significantly reduced cell viability and increased the number of apoptotic-like cells, indicating that H₂O₂ induced neurotoxicity. In addition, real-time PCR and western blot studies showed that Bcl-2 and Bcl-w expressions were decreased, and Bax expression was increased with H₂O₂ treatment. Moreover, protein kinase C (PKC) α expression was down-regulated after H₂O₂ treatment. All of these phenotypes induced by H₂O₂ were markedly reversed by L-NBP. Pretreatment with L-NBP significantly increased cell viability of H₂O₂-damaged cells, and reduced H₂O₂-induced neuronal apoptosis. L-NBP treatment at dose of 10 μM inhibited H₂O₂-induced down-regulation of Bcl-2, Bcl-w, and PKCα but also attenuated the overexpression of Bax. PKC inhibitor, calphostin C, significantly attenuated the protective effects of L-NBP. Our findings suggest that L-NBP may protect neurons against H₂O₂-induced apoptosis by modulating apoptosis-related genes and activating PKCα pathway. Topics: Apoptosis; Apoptosis Regulatory Proteins; bcl-2-Associated X Protein; Benzofurans; Cell Line, Tumor; Cell Survival; Gene Expression; Humans; Hydrogen Peroxide; Naphthalenes; Neuroblastoma; Neuroprotective Agents; Protein Kinase C; Protein Kinase C-alpha; Protein Kinase C-epsilon; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-bcl-2; Signal Transduction | 2011 |
L-3-n-butylphthalide improves cognitive impairment and reduces amyloid-beta in a transgenic model of Alzheimer's disease.
Alzheimer's disease (AD) is an age-related, progressive neurodegenerative disorder that occurs gradually and results in memory, behavior, and personality changes. L-3-n-butylphthalide (L-NBP), an extract from seeds of Apium graveolens Linn (Chinese celery), has been demonstrated to have neuroprotective effects on ischemic, vascular dementia, and amyloid-beta (Abeta)-infused animal models. In the current study, we examined the effects of L-NBP on learning and memory in a triple-transgenic AD mouse model (3xTg-AD) that develops both plaques and tangles with aging, as well as cognitive deficits. Ten-month-old 3xTg-AD mice were given 15 mg/kg L-NBP by oral gavage for 18 weeks. L-NBP treatment significantly improved learning deficits, as well as long-term spatial memory, compared with vehicle control treatment. L-NBP treatment significantly reduced total cerebral Abeta plaque deposition and lowered Abeta levels in brain homogenates but had no effect on fibrillar Abeta plaques, suggesting preferential removal of diffuse Abeta deposits. Furthermore, we found that L-NBP markedly enhanced soluble amyloid precursor protein secretion (alphaAPPs), alpha-secretase, and PKCalpha expression but had no effect on steady-state full-length APP. Thus, L-NBP may direct APP processing toward a non-amyloidogenic pathway and preclude Abeta formation in the 3xTg-AD mice. The effect of l-NBP on regulating APP processing was further confirmed in neuroblastoma SK-N-SH cells overexpressing wild-type human APP(695) (SK-N-SH APPwt). L-NBP treatment in 3xTg-AD mice also reduced glial activation and oxidative stress compared with control treatment. L-NBP shows promising preclinical potential as a multitarget drug for the prevention and/or treatment of Alzheimer's disease. Topics: ADAM Proteins; Alzheimer Disease; Amyloid beta-Peptides; Amyloid beta-Protein Precursor; Animals; Benzofurans; Cell Line, Tumor; Cell Survival; Cognition Disorders; Disease Models, Animal; Enzyme Inhibitors; Enzyme-Linked Immunosorbent Assay; Female; Humans; Indoles; Leukocyte Common Antigens; Male; Maleimides; Malondialdehyde; Maze Learning; Mice; Mice, Inbred C57BL; Mice, Transgenic; Mutation; Nerve Tissue Proteins; Neuroblastoma; Neuroglia; Neuroprotective Agents; Oxidative Stress; Presenilin-1; Reaction Time; Spatial Behavior; Statistics, Nonparametric; tau Proteins; Time Factors; Transfection | 2010 |
Salvianolic acid B protects SH-SY5Y neuroblastoma cells from 1-methyl-4-phenylpyridinium-induced apoptosis.
Parkinson's disease (PD) is associated with mitochondrial dysfunction, oxidative stress, and activation of the apoptotic cascade. In the study, we investigated the effects of salvianolic acid B (Sal B) on 1-methyl-4-phenylpyridinium (MPP(+))-treated SH-SY5Y cells, a classic in vitro model for PD. We found Sal B inhibited the loss of cell viability by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The underlying mechanisms of Sal B action were further studied. Treatment of SH-SY5Y cells with MPP(+) caused a loss of cell viability and mitochondrial membrane potential, condensation of nuclei, elevation in the level of reactive oxygen species (which was associated with cytochrome c release), an increase in the Bax/Bcl-2 mRNA ratio, and activation of caspase-3. Sal B ameliorated the MPP(+)-altered phenotypes. These results indicate that the Sal B protected SH-SY5Y cells against MPP(+)-induced apoptosis by relieving oxidative stress and modulating the apoptotic process. Our findings suggest that salvianolic acid B may be a promising agent to prevent PD. Topics: 1-Methyl-4-phenylpyridinium; Antiparkinson Agents; Apoptosis; bcl-2-Associated X Protein; Benzofurans; Biological Assay; Caspase 3; Cell Culture Techniques; Cell Line, Tumor; Cell Survival; Humans; Membrane Potential, Mitochondrial; Molecular Structure; Neuroblastoma; Parkinson Disease; Proto-Oncogene Proteins c-bcl-6; Reactive Oxygen Species; Reverse Transcriptase Polymerase Chain Reaction | 2010 |
NF-kappaB activation is associated with homocysteine-induced injury in Neuro2a cells.
Perinatal exposure to hyperhomocysteinemia might disturb neurogenesis during brain development and growth. Also, high levels of homocysteine trigger neurodegeneration in several experimental models. However, the putative mechanisms of homocysteine-induced toxicity in the developing nervous system have poorly been elucidated. This study was aimed to investigate homocysteine effects in undifferentiated neuroblastoma cells, Neuro2a.. A 4 h exposure to homocysteine in a concentration range of 10-100 microM did not affect cell viability and ROS production in Neuro2a cell cultures. Instead, ROS levels were increased by two-three folds in cells treated with 250 microM and 500 microM homocysteine, respectively, in comparison with control cells. Also, the highest homocysteine dose significantly reduced the viable cell number by 40%. Notably, the treatment with homocysteine (250 microM-500 microM) in the presence of antioxidants, such as N-acetylcysteine and IRFI 016, a synthetic alpha-tocopherol analogue, recovered cell viability and significantly reduced homocysteine-evoked increases in ROS production. Moreover, antioxidants, particularly IRFI 016, were able to counteract NF-kappaB activation induced by 250 microM homocysteine. Cell treatment with 250 microM homocysteine also triggered the onset of apoptosis, as demonstrated by the increased expression of early apoptotic markers such as Bax, caspase-3 and p53. In contrast, Bcl2 expression was not affected by homocysteine exposure. Interestingly, the specific inhibition of NF-kappaB nuclear translocation by the synthetic peptide SN50 was able to almost completely suppress the homocysteine-evoked rises in pro-apoptotic protein expression as well as in caspase-3 activity. Further, also IRFI 016 and N-acetylcysteine were able to significantly reduce caspase-3 activation induced by homocysteine treatment.. These observations suggest an involvement of redox state alterations and activated NF-kappaB in apoptosis onset triggered by homocysteine in neuroblastoma cells Neuro2a. However, further investigations are needed to characterize molecular events involved in the NF-kappaB activation induced by homocysteine. Topics: Acetylcysteine; alpha-Tocopherol; Animals; Apoptosis; bcl-2-Associated X Protein; Benzofurans; Blotting, Western; Caspase 3; Cell Differentiation; Cell Line, Tumor; Cell Survival; Dose-Response Relationship, Drug; Electrophoretic Mobility Shift Assay; Free Radical Scavengers; Homocysteine; Mitochondria; Neuroblastoma; NF-kappa B; Peptides; Proto-Oncogene Proteins c-bcl-2; Reactive Oxygen Species; Tumor Suppressor Protein p53; Vitamin E | 2008 |
Salvianolic acid B, an antioxidant from Salvia miltiorrhiza, prevents 6-hydroxydopamine induced apoptosis in SH-SY5Y cells.
Oxidative stress caused by dopamine may play an important role in the pathogenesis of Parkinson's disease. Salvianolic acid B is an antioxidant derived from the Chinese herb, Salvia miltiorrhiza. In this study, we investigated the neuroprotective effect of salvianolic acid B against 6-hydroxydopamine-induced cell death in human neuroblastoma SH-SY5Y cells. Pretreatment of SH-SY5Y cells with salvianolic acid B significantly reduced 6-hydroxydopamine-induced generation of reactive oxygen species, and prevented 6-hydroxydopamine-induced increases in intracellular calcium. Our data demonstrated that 6-hydroxydopamine-induced apoptosis was reversed by salvianolic acid B treatment. Salvianolic acid B reduced the 6-hydroxydopamine-induced increase of caspase-3 activity, and reduced cytochrome C translocation into the cytosol from mitochondria. The 6-hydroxydopamine-induced decrease in the Bcl-x/Bax ratio was prevented by salvianolic acid B. Additionally, salvianolic acid B decreased the activation of extracellular signal-regulated kinase and induced the activation of 6-hydroxydopamine-suppressed protein kinase C. These results indicate that the protective function of salvianolic acid B is dependent upon its antioxidative potential. Our results strongly suggest that salvianolic acid B may be effective in treating neurodegenerative diseases associated with oxidative stress. Topics: Adrenergic Agents; Antioxidants; Apoptosis; Apoptosis Regulatory Proteins; Benzofurans; Calcium; Caspase 3; Cell Line, Tumor; Cytochromes c; Drugs, Chinese Herbal; Humans; Neuroblastoma; Neuroprotective Agents; Oxidative Stress; Oxidopamine; Protein Kinase C; Reactive Oxygen Species; Salvia miltiorrhiza; Sympatholytics | 2008 |
l-3-n-Butylphthalide ameliorates beta-amyloid-induced neuronal toxicity in cultured neuronal cells.
l-3-n-Butylphthalide (l-NBP), as an anti-cerebral ischemia agent, has been shown to have therapeutic effects on learning and memory deficits induced by chronic cerebral hypoperfusion and Abeta intracerebroventricular infusion in rats. In the present study, we investigated the neuroprotective effects of l-NBP on beta-amyloid (Abeta)25-35-induced neuronal death/apoptosis and potential mechanisms in rat hippocampal neurons and human neuroblastoma SH-SY5Y cells. Abeta25-35 significantly reduced cell viability and increased the number of apoptotic-like cells, indicating that Abeta25-35-induced neurotoxicity. In addition, tau protein hyperphosphorylation was found to increase after Abeta exposure. All of these phenotypes induced by Abeta25-35 were markedly reversed by l-NBP. Pretreatment with l-NBP prior to Abeta25-35 exposure significantly elevated cell viability, and reduced Abeta25-35-induced nuclear fragmentation and early apoptosis. Furthermore, immunoreactivity for hyperphosphorylation tau protein was significantly decreased by l-NBP treatment. Our results suggest that l-NBP may protect neurons against Abeta-induced neurotoxicity via inhibiting tau protein hyperphosphorylation. Topics: Amyloid beta-Peptides; Animals; Apium; Apoptosis; Benzofurans; Brain Neoplasms; Cell Line, Tumor; Cell Survival; Drug Interactions; Hippocampus; Humans; Neuroblastoma; Neurons; Neuroprotective Agents; Peptide Fragments; Plant Extracts; Rats; Rats, Sprague-Dawley | 2008 |
Comparison of antioxidant activities between salvianolic acid B and Ginkgo biloba extract (EGb 761).
To investigate and compare the antioxidant activities of salvianolic acid B (SalB) and Ginkgo biloba extract (EGb 761) in aqueous solution, rat microsomes and the cellular system.. Superoxide anion (O2-.) was generated using xanthine/xanthine oxidase system and phenazine methosulate/NADH system, and the effects of SalB and EGb 761 on the generation of O2-.were achieved by spectrophotometric measurement of the product formed on reduction of nitro blue tetrazolium. Two different methods were used to assess the scavenging effects of the extracts on hydroxyl radical (. OH): HPLC method was used for quantitation of . OH by oxy-radical trapping of 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) to form DMPO-OH adducts in Fe2+-EDTA-H2O2 system. To confirm the HPLC data, .OH was also measured by spectrophotometry using a commercial detection kit. The anti-lipid peroxidation effects of the extracts in microsomes of rat brain, liver and kidney induced by ascorbate-NADPH were determined by thiobarbituric acid (TBA) method. The protective effects of the extracts on peroxide hydrogen (H2O2)-induced oxidative damage in SH-SY5Y cells were investigated by assessing cell viability assay, the level of lipid peroxidation, and the lactate dehydrogenase(LDH) release.. Both SalB and EGb 761 were able to scavenge O2-. and . OH, inhibit lipid peroxidation of microsomes, and protect SH-SY5Y cells against H2O2-induced oxidative damage. However, the concentration of SalB was far lower than that of EGb 761 when a similar effect was obtained.. The antioxidant efficiency of SalB was greater than that of EGb 761. These results suggest that SalB, like EGb 761, has promising potential in treating oxidative damage-derived neurodegenerative disorders. Topics: Animals; Antioxidants; Benzofurans; Brain; Cell Line, Tumor; Drugs, Chinese Herbal; Ginkgo biloba; Humans; Male; Neuroblastoma; Plant Extracts; Plants, Medicinal; Rats; Rats, Wistar; Salvia miltiorrhiza | 2006 |
Neuroprotective function of R-(-)-1-(benzofuran-2-yl)-2-propylaminopentane, [R-(-)-BPAP], against apoptosis induced by N-methyl(R)salsolinol, an endogenous dopaminergic neurotoxin, in human dopaminergic neuroblastoma SH-SY5Y cells.
R-(-)-1-(Benzofuran-2-yl)-2-propylaminopentane HCl [R-(-)-BPAP] is one of "catecholaminergic and serotonergic enhancers", which were proposed to improve symptoms through increase in impulse-evoked release of monoamine neurotransmitters for Parkinson's disease. It was reported that (-)-BPAP up-regulated the synthesis of neurotrophic factors in mouse astrocytes, suggesting the neuroprotective potency of (-)-BPAP. In this paper, the neuroprotective function of (-)-BPAP and the related compounds was examined against apoptosis induced by an endogenous neurotoxin, N-methyl(R)salsolinol [NM(R)Sal], a possible pathogenic toxin in Parkinson's disease, in human dopaminergic neuroblastoma SH-SY5Y cells. The anti-apoptotic activity was confirmed with some of (-)-BPAP analogues, and the mechanism was found to be due to the direct stabilization of mitochondrial membrane potential and the induction of anti-apoptotic Bcl-2. The studies on structure-activity relationship demonstrated that the potency to stabilize the mitochondrial membrane potential depended on the absolute stereo-chemical structure of BPAP derivatives. The compounds with dextrorotation prevented the mitochondrial permeability transition, whereas those with levorotation did not. The presence of a propargyl or propyl group at the amino residue of R-(-)-1-(benzofuran-2-yl)-2-propylamine increased potency to stabilize the membrane potential and prevent apoptosis. R-FPFS-1169 and R-FPFS-1180 had more potent to induce Bcl-2 and prevent apoptosis than the corresponding S-enantiomers. These results are discussed with the possible application of BPAP derivatives as neuroprotective agents in Parkinson's disease and other neurodegenerative disorders. Topics: Apoptosis; Benzofurans; Electrophoresis, Polyacrylamide Gel; Flow Cytometry; Humans; Neuroblastoma; Neuroprotective Agents; Neurotoxins; Proto-Oncogene Proteins c-bcl-2; Receptors, Dopamine; Salsoline Alkaloids; Structure-Activity Relationship; Tetrahydroisoquinolines; Tumor Cells, Cultured | 2004 |
5-HT3 receptor-independent inhibition of the depolarization-induced 86Rb efflux from human neuroblastoma cells, TE671, by ondansetron.
The 5-HT3-receptor antagonist, ondansetron, has been shown to have positive effects in selected in-vivo models of memory impairment and anxiety. The exact mechanisms underlying such bioactivities are unknown. In the present work, an 86Rb efflux bioassay was used to show that ondansetron has a unique ability to block voltage-gated potassium channels in TE671 human neuroblastoma cells. This intrinsic potassium-channel-blocking (KCB) property is relatively weak (IC50 20 microM), but is not shared by other 5-HT3-receptor ligands including zatosetron, MDL 72222, LY 278, 584, zacopride, 1-phenylbiguanide, and ICS 205-930 (tropisetron). Pre-incubation of the target neuroblastoma cells with several 5-HT-receptor ligands including 5-hydroxytryptamine, 8-OH-DPAT, ketanserin, 2-methyl-5-HT, as well as a number of potent 5-HT3 agonists and antagonists and two selective neurotoxins, failed to abolish the KCB action of ondansetron. A preliminary structure-activity relationship analysis indicates that the KCB activity of ondansetron is almost entirely attributable to its structural nucleus, 2,3-dihyro-9-methyl-4(1H)-carbazolone. It is hypothesized that the KCB action of ondansetron is mediated through receptors other than 5-HT3 receptors. The KCB activity of ondansetron may be a significant factor in the in-vivo cognition-enhancing activities of this compound, conceivably due to depolarization of the hippocampal synaptic membranes and a consequent augmentation of neurotransmission. Topics: Anti-Anxiety Agents; Benzamides; Benzofurans; Biguanides; Bridged Bicyclo Compounds, Heterocyclic; Humans; Hypoglycemic Agents; Indazoles; Indoles; Neuroblastoma; Neurotoxins; Ondansetron; Potassium Channels; Receptors, Serotonin; Receptors, Serotonin, 5-HT3; Rubidium Radioisotopes; Serotonin Antagonists; Serotonin Receptor Agonists; Structure-Activity Relationship; Tropanes; Tropisetron; Tumor Cells, Cultured | 1995 |
Menthol blocks dihydropyridine-insensitive Ca2+ channels and induces neurite outgrowth in human neuroblastoma cells.
Voltage-gated Ca2+ channels were identified in LA-N-5 human neuroblastoma cells using the Ca2+ sensitive fluorescent probe, fura-2. Using a variety of "classical" Ca2+ channel blockers, we have demonstrated the presence of both dihydropyridine (DHP)-sensitive and -insensitive channel types that can be activated by depolarization of the cells with either high K+ or gramicidin in the bathing solution. Brief exposure of LA-N-5 cells to menthol blunted the depolarization-induced Ca2+ influx though both DHP-sensitive and DHP-insensitive channels. This effect is concentration dependent (50% maximal blocking effect with 0.25 mM menthol), rapid in onset, and readily reversible. The specificity of the Ca2(+)-channel blocking effect of menthol was demonstrated in parallel studies using compounds with similar structures: menthone blocked Ca2+ channels with about half the potency of menthol, while cyclohexanol was without effect. Addition of either menthol or menthone to LA-N-5 cultures induced neurite outgrowth, cellular clustering, and reduction of cell growth in a dose-dependent fashion that correlated with the ability of these compounds to inhibit the DHP-insensitive Ca2+ influx. Cyclohexanol had no biologic activity. Taken together, the parallel potency for blockade of DHP-insensitive Ca2+ influx with the biologic activity of menthol suggests a role for certain types of Ca2+ channels in triggering growth and morphologic changes in LA-N-5 cells. Topics: Acetylcholinesterase; Axons; Benzofurans; Calcium; Calcium Channel Blockers; Calcium Channels; Cell Division; Cyclohexanols; Dihydropyridines; Fluorescent Dyes; Fura-2; Humans; Menthol; Neuroblastoma; Terpenes; Tumor Cells, Cultured | 1990 |
Calcium hotspots caused by L-channel clustering promote morphological changes in neuronal growth cones.
Topics: Action Potentials; Axons; Benzofurans; Calcium; Calcium Channels; Cell Membrane; Electric Conductivity; Electric Stimulation; Fluorescent Dyes; Fura-2; Microscopy, Fluorescence; Neuroblastoma; Neurons; Tumor Cells, Cultured | 1990 |
Angiotensin II effects on the cytosolic free Ca2+ concentration in N1E-115 neuroblastoma cells: kinetic properties of the Ca2+ transient measured in single fura-2-loaded cells.
The effect of angiotensin II on the cytosolic free Ca2+ concentration was measured in single mouse neuroblastoma N1E-115 cells loaded with fura-2. Angiotensin II induced a transient concentration-dependent increase in Ca2+ and also increased the production of inositol polyphosphates. The Ca2+ increase did not require extracellular Ca2+ and was unaffected by pretreatment with pertussis toxin. These data suggest that angiotensin II increased Ca2+ by an inositol trisphosphate-mediated release of intracellular Ca2+ following activation of phospholipase C via a pertussis toxin-insensitive guanine nucleotide binding protein. Similar results were obtained with bradykinin. The angiotensin II- or bradykinin-induced increase in Ca2+ occurred after a concentration-dependent latent period. Low concentrations of agonist elicited a small increase in Ca2+ following a variable lag that sometimes exceeded 1 min, whereas at maximally effective angiotensin II concentrations a larger, more rapid increase in Ca2+ occurred without a measurable delay. In some cells, oscillatory increases in Ca2+ were induced by angiotensin II and bradykinin. Possible mechanisms to explain the concentration dependency of the latent period and the oscillatory nature of the increases of Ca2+ are discussed. These results indicate that the mouse neuroblastoma N1E-115 cell represents a useful model for studying the signal response transduction mechanisms regulating the effects of angiotensin II in neuronal cells. Topics: Angiotensin II; Animals; Benzofurans; Bradykinin; Calcium; Cell Differentiation; Cell Division; Cell Line; Cytosol; Fluorescent Dyes; Fura-2; Inositol Phosphates; Kinetics; Mice; NAD; Neuroblastoma; Pertussis Toxin; Tumor Cells, Cultured; Virulence Factors, Bordetella | 1990 |
12-O-tetradecanoylphorbol 13-acetate and forskolin modify muscarinic receptor-linked Ca2+ mobilization in SH-SY5Y neuroblastoma cells through different mechanisms.
The phorbol ester, 12-O-tetradecanoylphorbol 13-acetate (TPA), which causes differentiation of SH-SY5Y neuroblastoma cells, reduces carbachol binding and carbachol-stimulated Ca2+ mobilization in these cells. The decrease in responsiveness to carbachol is due partially to a reduction in the amount of Ca2+ released by the cells and partially to a decrease in the sensitivity of the cells to carbachol. These effects probably can be attributed to a reduction in muscarinic receptor number and a decrease in receptor affinity, respectively. Forskolin, an alkaloid known to cause an increase in cellular cyclic AMP, enhances Ca2+ influx into the cells without affecting the cytosolic free Ca2+ concentration. The alkaloid causes an apparent restoration of the reduced Ca2+ release, caused by TPA, but does not affect the sensitivity of the cells to carbachol. Forskolin increases the decay of carbachol-induced increase in cytosolic Ca2+. The effects of TPA appear to be linked directly to receptor function, whereas those of forskolin are due to the effect of cyclic AMP on cellular Ca2+ metabolism. Topics: Benzofurans; Binding, Competitive; Biomechanical Phenomena; Calcium; Carbachol; Colforsin; Cytosol; Fluorescent Dyes; Fura-2; Ionomycin; Membrane Potentials; N-Methylscopolamine; Neuroblastoma; Osmolar Concentration; Receptors, Muscarinic; Scopolamine Derivatives; Tetradecanoylphorbol Acetate; Tumor Cells, Cultured | 1990 |
Muscarinic-receptor-mediated changes in intracellular Ca2+ and inositol 1,4,5-trisphosphate mass in a human neuroblastoma cell line, SH-SY5Y.
This study reports increased intracellular Ca2+ and inositol 1,4,5-trisphosphate [Ins(1,4,5)P3] in response to muscarinic-cholinergic stimulation of human neuroblastoma (SH-SY5Y) cells. Carbachol stimulation leads to a rapid increase in intracellular Ca2+ and Ins(1,4,5)P3 mass, both reaching a peak at around 10 s and then declining to a new maintained phase significantly above basal. Dose-response analysis of peak and plateau phases of intracellular Ca2+ shows different agonist potencies for both phases, carbachol being more potent for the plateau phase. The plateau-phase intracellular Ca2+ was dependent on extracellular Ca2+, which is admitted to the cell through a non-voltage-sensitive Ni2(+)-blockable Ca2+ channel. Using a Mn2+ quench protocol, we have shown that Ca2+ entry occurs early during the discharge of the internal stores. The plateau phase (Ca2(+)-channel opening) is dependent on the continued presence of agonist, since addition of atropine closes the Ca2+ channel and intracellular Ca2+ declines rapidly back to basal. We also failed to detect a refilling transient when we added back Ca2+ after intracellular Ca2+ had reached a peak and then declined in Ca2(+)-free conditions. These data strongly suggest that muscarinic stimulation of SH-SY5Y cells leads to a rapid release of Ca2+ from an Ins(1,4,5)P3-sensitive internal store and a parallel early entry of Ca2+ across the plasma membrane. Topics: Arecoline; Atropine; Benzofurans; Calcium; Carbachol; Cell Line; Fluorescent Dyes; Fura-2; Humans; Inositol 1,4,5-Trisphosphate; Ionomycin; Kinetics; Manganese; Muscarine; Neuroblastoma; Receptors, Muscarinic; Tumor Cells, Cultured | 1990 |
Muscarinic receptors coupled to phosphoinositide hydrolysis and elevated cytosolic calcium in a human neuroblastoma cell line SK-N-SH.
1. The effects of the muscarinic agonist carbachol on phosphoinositide metabolism and its relationship to alteration of intracellular calcium were examined in SK-N-SH human neuroblastoma cells. Muscarinic receptors on these cells are coupled to phospholipase C and the myo [2-3H]-inositol phosphates resulting from receptor activation of cells labelled with [3H]-inositol accumulate rapidly. The breakdown of both inositol monophosphate (InsP1) and inositol bisphosphate (InsP2) is sensitive to lithium with inhibition of the latter only observed at higher concentrations of this ion. 2. Use of the calcium indicator dye Fura 2 revealed that carbachol stimulates a biphasic increase in intracellular calcium. 3. Carbachol was able to stimulate both [3H]-inositol phosphate production and intracellular calcium levels with respective EC50 values of 15.9 +/- 1.0 microM and 10.7 +/- 3.2 microM, indicating that no amplification occurs between these steps in the signal transduction pathway. 4. Inositol 1,4,5 trisphosphate (Ins(1,4,5)P3) released 45Ca2+ in a stereospecific and dose-related manner from intracellular stores of permeabilised cells. 5. These results suggest that this cell line may represent a useful model system to investigate receptor-mediated phosphoinositide metabolism and calcium homeostasis. Topics: Benzofurans; Calcium; Carbachol; Cytosol; Fura-2; Humans; Hydrolysis; Inosine Triphosphate; Neuroblastoma; Phosphatidylinositols; Receptors, Muscarinic; Tumor Cells, Cultured | 1989 |
Elevated cytosolic calcium in the growth cone inhibits neurite elongation in neuroblastoma cells: correlation of behavioral states with cytosolic calcium concentration.
Schubert (1984) and Kater et al. (1988) have suggested that motility and growth at the neuronal growth cone is activated by an increase of cytosolic free calcium concentration ([Ca2+]i) above the levels found in quiescent growth cones. In order to test this model, we have used a digital imaging fluorescence microscope together with injection of the fluorescent indicator dye Fura-2 to measure [Ca2+]i in growth cones of a mammalian sympathetic neuron, the N1E-115 neuroblastoma cell. The behavior of individual growth cones, together with spontaneously varying levels of [Ca2+]i within the growth cone, were monitored for periods of up to several hours. [Ca2+]i in motile, advancing growth cones was low and equal to [Ca2+]i in quiescent growth cones. Higher values of [Ca2+]i were found in motile growth cones that were not advancing, suggesting that a small elevation of [Ca2+]i inhibits neurite extension. A further rise of [Ca2+]i above the level found in motile, nonadvancing growth cones appeared to inhibit motility and cause retraction of the growth cone back towards the cell body. Spatial gradients of [Ca2+]i within the growth cone were small and, where statistically significant, [Ca2+]i was lower by 5-10 nM in motile regions. Our results are incompatible with the model that a rise of [Ca2+]i is responsible for activating quiescent growth cones; however, our results suggest that in active growth cones [Ca2+]i can regulate morphology and behavior. Topics: Animals; Axons; Benzofurans; Calcium; Cell Line; Cytosol; Fluorescent Dyes; Fura-2; Neuroblastoma; Tumor Cells, Cultured | 1989 |
Heterologous desensitization of bradykinin-induced phosphatidylinositol response and Ca2+ mobilization by neurotensin in NG108-15 cells.
The heterologous desensitization of the bradykinin (BK)-induced increase in intracellular Ca2+ concentration ([Ca2+]i) by neurotensin was studied in neuroblastoma x glioma hybrid NG108-15 cells. The addition of neurotensin to the cells resulted in an increase in [Ca2+]i and an increase in the formation of inositol phosphates in Ca2+-free medium. Pretreatment of the cells with neurotensin resulted in 43% decrease in the BK-induced increase of [Ca2+]i. The increase in [Ca2+]i induced by ionomycin, which causes Ca2+ release from the intracellular pool, was not decreased by pretreatment with neurotensin. This indicates that the inhibitory effect of neurotensin on the BK-induced increase of [Ca2+]i was not due to depletion of the intracellular Ca2+ pool. Pretreatment with neurotensin also caused a 47% decrease in the BK-induced formation of inositol trisphosphates (IP3). This decrease was not due to depletion of phosphatidylinositol bisphosphates. Neurotensin did not inhibit [3H]BK binding to cell membranes. These results show that neurotensin desensitizes the BK responses of NG108-15 cells, heterologously, perhaps by changes in phospholipase C and/or guanine nucleotide-binding protein (G-protein). Topics: Animals; Benzofurans; Bradykinin; Calcium; Cell Membrane; Cells, Cultured; Fura-2; Glioma; Inositol Phosphates; Mice; Neuroblastoma; Neurotensin; Phosphatidylinositols; Rats; Time Factors | 1989 |
Inhibitors of membrane transport system for organic anions block fura-2 excretion from PC12 and N2A cells.
The neuroblastoma-like cell line N2A and the pheochromocytoma-like cell line PC12 excrete about 20-25% of the intracellular fluorescent Ca2+ indicator fura-2 during 10 min of incubation at 37 degrees C. The drug probenecid, known to inhibit membrane systems for the transport of organic anions [Cunningham, Israili & Dayton (1981) Clin. Pharmacol. 6, 135-151], inhibited fura-2 excretion in both cell types. However, probenecid also had untoward effects on intracellular Ca2+ homeostasis in N2A and PC12 cells. We therefore tested the drug sulphinpyrazone, another known inhibitor of organic-anion transport systems. Sulphinpyrazone fully inhibited excretion of fura-2 at 250 microM, a concentration one order of magnitude lower than that of probenecid. At this concentration and for incubation times up to 20 min, sulphinpyrazone had no untoward effects on cell viability and metabolic functions. Fura-2 was also loaded into the cytoplasm of N2A cells by permeabilization of the plasma membrane with extracellular ATP. In this case as well, the dye was rapidly released from the cells and the efflux was blocked by sulphinpyrazone. These findings suggest that N2A and PC12 cells possess a membrane system for the transport of the free-acid form of fura-2. This transport system is probably responsible for the excretion of fura-2 from these cells. Incubation of N2A and PC12 cells with sulphinpyrazone may help overcome problems arising in the investigation of [Ca2+]i homeostasis in these cell types. Topics: Animals; Benzofurans; Biological Transport; Calcium; Cell Line; Cell Membrane Permeability; Fluorescent Dyes; Fura-2; Homeostasis; Neuroblastoma; Pheochromocytoma; Sulfinpyrazone; Tumor Cells, Cultured | 1988 |