• BMB Reports
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• v.41 no.6
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• pp.479-484
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• 2008

In the present study, we demonstrate that ephrin-A5 is able to induce a transient increase of MAP kinase activity in PC12 cells. However, the effects of ephrin-A5 on the MAP kinase signaling pathway are about three-fold less than that of EGF. In addition, we demonstrate that EphA4 is the only Eph member expressed in PC12 cells, and that tyrosine phosphorylation induced by ephrin-A5 treatment is consistent with the magnitude and longevity of MAP kinase activation. Experiments using the Ras dominant negative mutant N17Ras reveal that Ras plays a pivotal role in ephrin-A5-induced MAP kinase activation in PC12 cells. Importantly, we found that the EphA4 receptor is rapidly internalized by endocytosis upon engagement of ephrin-A5, leading to a subsequent reduction in the MAP kinase activation. Together, these data suggest a novel regulatory mechanism of differential Ras-MAP kinase signaling kineticsexhibited by the forward signaling of EphA4 in PC12 cells.

• Journal of the Korean Society of Food Culture
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• v.33 no.1
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• pp.86-94
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• 2018

This study was designed to evaluate the antioxidant activities and protective effects on PC12 cells of the extract of Epimedium koreanum and its main constituents icariin and icariside I. After screening the seven identified flavonoid glycosides from E. koreanum through DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) assay, E. koreanum, Icariin and Icariside I exhibited significant effect on radical scavenging activity. E. koreanum, icariin and icariside I were examined using DPPH, ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) and FRAP (ferric reducing ability power) assay. In all antioxidant assays, E. koreanum, icariin and icariside I showed high radical scavenging activities in a dose-dependent manner. Protective effects against $H_2O_2-induced$ PC12 cells were assessed with MTT assay. The results indicated that cell viability and protection on PC12 cells of icariside I and icariin increased dose dependently. These study results suggest that E. koreanum, icariin and icariside showed high antioxidant capacities and cell protective effects. Icariside I, one of the metabolites of icariin, may be a new and effective flavonoid compound as a functional component.

• Journal of Korean Medicine for Obesity Research
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• v.16 no.2
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• pp.79-84
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• 2016

Objectives: The purpose of this study was to observe the effects of Citri Reticulatae Viride Pericarpium (CP) on 4-Hydroxynonenal (4-HNE)-induced inflammation in PC12 cells. Methods: 4-HNE was treated in PC12 cell to cause inflammatory response, and then treated with CP water extract at 25, 50, and $100{\mu}g/ml$. The phosphorylation of Jun N-terminal kinase (JNK) and the expression of $NF-{\kappa}B$ in PC12 cells were determined by Western blot, respectively. Results: The phosphorylation of JNK was significantly decreased in 4-HNE-stimulated PC12 cell by the treatment of CP extract at $25{\mu}g/ml$. The 4-HNE-induced expression of nuclear factor kappa-light-chain-enhancer of activated B cells ($NF-{\kappa}B$) p65 in nuclear of the cells was significantly decreased in PC12 cell by treatment with CP extract at 25, 50, and $100{\mu}g/ml$. Conclusions: These results suggest that CP water extract has an anti-inflammatory activity through suppressing the JNK and $NF-{\kappa}B$ activation.

• Journal of the Korean Applied Science and Technology
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• v.36 no.2
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• pp.468-478
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• 2019

The aim of this study is to evaluate the efficacy of cordyceps militaris extracts for the improvement of cognitive dysfunction in PC12 and BV2 cells. Cordyceps militaris extracts was prepared by extracting with distilled water. Cell viability was assessed by MTT assay using PC12 cells and BV2 cells. Confirmed effects of L-glutamate induced cytotoxicity test, Acetylcoline (ACh) concentration, and Acetylcolinestase (AChE) activity in PC12 cells. Anti-inflammatory activities of cordyceps militaris extracts was measured through changes in the levels of nitric oxide (NO), and prostaglandin E2 ($PGE_2$) on lipopolysaccharide(LPS)-induced BV2 cell. In addition, we measured the expression of $NF-{\kappa}B$, p38, JNK, and caspase-3 in western blot analysis. Cordyceps militaris extracts showed no cytotoxicity at the concentrations of 1, 10, and $100{\mu}g/m{\ell}$ except for the concentration of $200{\mu}g/m{\ell}$. Cordyceps militaris extracts protected the cell and exhibited significant increases in the ACh concentration and a significant decrease in the AChE activity in L-glutamate induced PC12 cells. Moreover, cordyceps militaris extracts inhibited the productions NO, and PGE2 level and the protein expression of $NF-{\kappa}B$, p38, JNK, caspase-3 in LPS-induced BV2 cells. These results indicate that cordyceps militaris extracts possible prevented and improved cognitive dysfuction symptoms. Thus, cordyceps militaris extracts may be a novel natural material option for the improvement of cognitive dysfunction.

• BMB Reports
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• v.43 no.5
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• pp.369-374
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• 2010

The PC12 is the widely used cell line to study neuronal differentiation. We had extensively investigated the details of protein expression in differentiated PC12 cells by proteomic analysis. The cells were incubated at the presence of nerve growth factor. We had analyzed the expression changes in the differentiating PC12 cells by 2-dimensional electrophoresis and the identification of the proteins using MALDI-TOF MS. By comparing expression pattern in the time course, we identified the candidate genes which are associated with neuronal differentiation. Among these genes, we performed real-time PCR analysis to validate $Idh3{\alpha}$ expression by the time course. To identify the function of $Idh3{\alpha}$ in neuronal differentiation stage, the transfection of $Idh3{\alpha}$ to PC12 cells was performed. As a result, we proved that up-regulation of $Idh3{\alpha}$ causes reduction in neural differentiation of PC12 cells. Based on these data, we suggest that $Idh3{\alpha}$ plays a role to the neuronal differentiation.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.6
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• pp.699-705
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• 1997

Although it is known that neuronal cell death during development occurs by apoptosis, the mechanisms underlying excitatory amino acid-induced neuronal cell death remain poorly understood. In this study we have examined the mechanism by which L-glutamate, an excitatory amino acid neurotransmitter, induces cell death in PC12 cell lines. To characterize cell death, we employed sandwich enzyme-linked immunosorbent assay(ELISA) method for cellular DNA fragmentation, DNA agarose gel electrophoresis and chromatin staining by acridine orange and ethidium bromide after treating the PC12 cells with L-glutamate. L-Glutamate caused dose-dependent cell death with a maximum at 24 hrs after the treatment. These cellular fragmentation was blocked by pretreatment of MK-801, a noncompetitive N-methyl-D-aspartic acid(NMDA) receptor antagonist, and nerve growth factor(NGF). Analysis of DNA integrity from L-glutamate-treated cells revealed cleavage of DNA into regular sized fragments, a biochemical hallmark of apoptosis. The PC12 cells that were induced to die by L-glutamate treatment exhibited classical chromatin condensation under the light microscopy after acridine orange and ethidium bromide staining. These results suggest that apoptosis is one of the key features that are involved in L-glutamate-induced excitotoxic cell death in PC12 cells, and these cell death are mediated by NMDA receptor and depend on NGF.

• Korean Journal of Food Science and Technology
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• v.37 no.3
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• pp.479-483
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• 2005

Antioxidative and protective effects of Ulmus davidiana var. japonica against oxidative damages induced by glutamate in PC 12 cells were investigated. Inhibitory activity against $FeSO_{4}-H_{2}O_{2}$-induced oxidative stress and DPPH radical-scavenging activity were detected in ethyl acetate and butanol fractions of ethanol extracts from stems and roots. Ethyl acetate and butanol fractions of ethanol extracts from roots significantly inhibited glutamate-induced cytotoxicity and reactive oxygen species in PC 12 cells. These results demonstrate ethyl acetate and butanol fractions of ethanol extracts of U. davidiana var. japonica have potent protective effect against glutamate-induced oxidative stress.

• The Journal of Korean Medicine
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• v.24 no.1
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• pp.110-121
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• 2003

Objective : This research was performed to investigate the protective effect of Angelicae Dahuri Radix against ischemic damage using PC12 cells and global ischemia in gerbils. Methods : To observe the protective effect of Angelicae Dahuri Radix on ischemia damage, viability and changes in activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase and production of malondialdehyde (MDA) were observed after treating PC12 cells with Angelicae Dahuri Radix during ischemic insult. Gerbils were divided into three groups : a normal group, a 5-min two-vessel occlusion (2VO) group, and an Angelicae Dahuri Radix administered after 2VO group. The CCAs were occluded by microclip for 5 minutes. Angelicae Dahuri Radix was administered orally for 7 days after 2VO. The histological analysis was performed at 7 days after surgery. For histological analysis, the brain tissue was stained with 1% cresyl violet solution. Results : 1. Angelicae Dahuri Radix has a protective effect against ischemia in the CA1 area of the gerbil hippocampus 7 days after 5-minute occlusion, 2. In the hypoxia/reperfusion model using PC12 cells, Angelicae Dahuri Radix has a protective effect against ischemia in the dose of $0.2\mu\textrm{g}/ml$, $2\mu\textrm{g}/ml$ and $20\mu\textrm{g}/ml$, 3. Angelicae Dahuri Radix increased the activities of glutathione peroxidase and catalase. 4. The activity of superoxide dismutase (SOD) was increased by ischemic damage, which might represent self protection. This study suggests that Angelicae Dahuri Radix has some neuroprotective effect against neuronal damage following cerebral ischemia in vivo with a widely used experimental model of cerebral ischemia in Mongolian gerbils, and it also has protective effects on a hypoxia/reperfusion cell culture model using PC12 cells. Conclusions : Angelicae Dahuri Radix has protective effects against ischemic brain damage at the early stage of ischemia.

• The Journal of Korean Medicine
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• v.23 no.4
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• pp.113-124
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• 2002

Objects: This research was conducted to investigate the protective effect of Bupleuri Radix against ischemic damage using PC12 cells and global ischemia in gerbils, Methods: To observe the protective effect of Bupleuri Radixon ischemic damage, viability and changes in activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase and production of malondialdehyde (MDA) were observed after treating PC12 cells with Bupleuri Radix during ischemic damage. Gerbils were divided into three groups: a normal group, a 5-minute two-vessel occlusion (2VO) group and a Bupleun Radix administered group after 2VO. The CCAs were occluded by microclip for 5 minutes, Bupleuri Radix was administered orally for 7 days after 2VO. Histological analysis was performed on the 7th day. For histological analysis, the brain tissue was stained with 1 % of cresyl violet solution. Results: 1. Bupleuri Radix has a protective effect against ischemia in the CA1 area of the gerbil's hippocampus 7 days after 5-minute occlusion. 2. In the hypoxia/reperfusion model using PC12 cells, the Bupleuri Radix has a protective effect against ischemia in the dose of 0.2{\;}\mu\textrm{g}/ml,2{\;}\mu\textrm{g}/ml{\;}and{\;} 20{\;}\mu\textrm{g}/ml$. 3. Bupleuri Radix increased the activities of glutathione peroxidase and catalase. 4. The increased activity of superoxidedismutase (SOD) by ischemic damage might have been induced as an act of self-protection. This study suggests that Bupleuri Radix has some neuroprotective effect against neuronal damage following cerebral ischemia in vivo with a widely used experimental model of cerebral ischemia in Mongolian gerbils. Bupleuri Radix also has protective effect on a hypoxia/reperfusion cell culture model using PC12 cells. Conclusions: Bupleuri Radix has protective effect against ischemic brain damage during the early stages of ischemia.

• The Korean Journal of Physiology and Pharmacology
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• v.10 no.1
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• pp.51-58
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• 2006

The promoting effect of hydrogen peroxide ($H_2O_2$) against the cytotoxicity of 1-methyl-4-phenylpyridinium ($MPP^+$) in differentiated PC12 cells was assessed by measuring the effect on the mitochondrial membrane permeability. Treatment of PC12 cells with $MPP^+$ resulted in the nuclear damage, decrease in the mitochondrial transmembrane potential, cytosolic accumulation of cytochrome c, activation of caspase-3, increase in the formation of reactive oxygen species (ROS) and depletion of GSH. Addition of $H_2O_2$ enhanced the $MPP^+-induced$ nuclear damage and cell death. Catalase, Carboxy-PTIO, Mn-TBAP, N-acetylcysteine, cyclosporin A and trifluoperazine inhibited the cytotoxic effect of $MPP^+$ in the presence of $H_2O_2$. Addition of $H_2O_2$ promoted the change in the mitochondrial membrane permeability, ROS formation and decrease in GSH contents due to $MPP^+$ in PC12 cells. The results show that the $H_2O_2$ treatment promotes the cytotoxicity of $MPP^+$ against PC12 cells. $H_2O_2$ may enhance the $MPP^+$-induced viability loss in PC12 cells by promoting the mitochondrial membrane permeability change, release of cytochrome c and subsequent activation of caspase-3, which is associated with the increased formation of ROS and depletion of GSH. The findings suggest that $H_2O_2$ as a promoting agent for the formation of mitochondrial permeability transition may enhance the neuronal cell injury caused by neurotoxins.