• BMB Reports
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• 제37권4호
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• pp.480-486
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• 2004

Brain ischemia brings about hypoxic insults. Hypoxia is one of the major pathological factors inducing neuronal injury and central nervous system infection. We studied the involvement of mitogen-activated protein (MAP) kinase in hypoxia-induced apoptosis using cobalt chloride in C6 glioma cells. In vitro cytotoxicity of cobalt chloride was tested by MTT assay. Its $IC_{50}$ value was $400\;{\mu}M$. The DNA fragment became evident after incubation of the cells with $300\;{\mu}M$ cobalt chloride for 24 h. We also evidenced nuclear cleavage with morphological changes of the cells undergoing apoptosis with electron microscopy. Next, we examined the signal pathway of cobalt chloride-induced apoptosis in C6 cells. The activation of extracellular signal-regulated protein kinase 1/2 (ERK 1/2) started to increase at 1 h and was activated further at 6 h after treatment of 400 M cobalt chloride. In addition, pretreatment of PD98059 inhibited cobalt chloride-induced apoptotic cell morphology in Electron Microscopy. These results suggest that cobalt chloride is able to induce the apoptotic activity in C6 glioma cells, and its apoptotic mechanism may be associated with signal transduction via MAP kinase (ERK 1/2).

• The Journal of Korean Obstetrics and Gynecology
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• 제19권1호
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• pp.69-80
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• 2006

Purpose : This study is to evaluate the synergistic cytotoxicity of Rhizoma Rehmanniae(RR), in adriamycin-treated HeLa human cervical carcinoma cells. Methods : We culture HeLa cell which is human metrocarcinoma cell in D-MEM included 10% fetal bovine serum(Hyclone Laboratories) below $37^{\circ}C$, 5% $CO_2$. Then we observed apoptosis of log phage cell which is changed cultivation liquid 24 Hours periodically. Results : The combination of RR and adriamycin synergistically augmented the cytotoxicity of HeLa cells. The apoptotic cell death was accompanied by the activation of caspase-3 and -8 as well as cleavage of poly(ADP- ribose) polymerase (PARP) in HeLa cells. The co-treatment of RR with adriamycin didn't have any effect on either the expression of Bcl-2 or that of Bax. Interestingly, a synergistic increase in apoptosis by the combination of two drugs was accompanied by the enhancement of Pas and Fas ligand (FasL) expression in HeLa cells. Taken together, the combination of RR and adriamycin significantly augmented the apoptotic cytotoxicity of Fas-positive cells, such as HeLa cells. The pathway is not involved in mitochondria-dependent pathway. Conclusion : RR induces apoptosis in HeLa cells via p38 MAPK activation.

• Korean Journal of Veterinary Research
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• 제54권1호
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• pp.1-6
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• 2014

Parkinson's disease is known to exhibit progressive degeneration of the dopaminergic neurons in the substantia nigra via inhibition of glutathione metabolism. It is well known that 6-Hydroxydopamine (6-OHDA) induces Parkinson's disease-like symptoms, while resveratrol (3,5,4'-trihydroxystilbene) has been shown to have anti-inflammatory and antioxidant effects. In the present study, we investigated the neuroprotective effects of resveratrol, a phytoalexin found in grapes and various plants, on 6-OHDA-induced cell damage to the SH-SY5Y human neuroblastoma cell line. Resveratrol (5 and 10 ${\mu}M$) inhibited 6-OHDA (60 ${\mu}M$)-induced cytotoxicity in SH-SY5Y cells and induced a reduction of the number of apoptotic nuclei caused by 6-OHDA treatment. Additionally, the total apoptotic rate of cells treated with both resveratrol (10 ${\mu}M$) and 6-OHDA (60 ${\mu}M$) was less than that of 6-OHDA treated cells. Resveratrol also dose-dependently (1, 5 and 10 ${\mu}M$) scavenged reactive oxygen species (ROS) induced by 6-OHDA in SH-SY5Y cells and prevented depletion of glutathione in response to the 6-OHDA-induced cytotoxicity in the glutathione assay. Overall, these results indicate that resveratrol exerts a neuroprotective effect against 6-OHDA-induced cytotoxicity of SH-SY5Y cells by scavenging ROS and preserving glutathione.

• Korean Journal of Veterinary Research
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• 제57권1호
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• pp.1-7
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• 2017

Parkinson's disease (PD) is an irreversible neurological disorder with related locomotor dysfunction and is characterized by the selective loss of nigral neurons. PD can be experimentally induced by 6-hydroxydopamine (6-OHDA). It has been reported that reactive oxygen species, which deplete endogenous glutathione (GSH) levels, may play important roles in the dopaminergic cell death characteristic of PD. Fucoidan, a sulfated algal polysaccharide, exhibits anti-inflammatory and anti-oxidant actions. In this study, we investigated whether fucoidan can protect against 6-OHDA-mediated cytotoxicity in SH-SY5Y cells. Cytotoxicity was evaluated by using MTT and LDH assays. Fucoidan alleviated cell damage evoked by 6-OHDA dose-dependently. Fucoidan reduced the number of apoptotic nuclei and the extent of annexin-V-associated apoptosis, as revealed by DAPI staining and flow cytometry. Elevation of lipid peroxidation and caspase-3/7 activities induced by 6-OHDA was attenuated by fucoidan, which also protected against cytotoxicity evoked by buthionine-sulfoximine-mediated GSH depletion. Reduction in the glutathione/glutathione disulfide ratio induced by 6-OHDA was reversed by fucoidan, which also inhibited 6-OHDA-induced disruption of mitochondrial membrane potential. The results indicate that fucoidan may have protective action against 6-OHDA-mediated neurotoxicity by modulating oxidative injury and apoptosis through GSH depletion.

• Environmental Mutagens and Carcinogens
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• 제20권1호
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• pp.14-20
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• 2000

DHAQ-97, (2-(3-[p-bis(2-chloroethyl)aminophenyl]-2 formylaminopropanoyloxy) methy1-1,4-dihy-droxy-9,10-anthraquinone), is a novel anthraquinone derivative synthesized for use as an anti-neoplastic agent. In the present study, we have evaluated the selective cytotoxicity of DHAQ-97 by comparing its effects on viability and proliferation of human breast cancer cell line (NCF-7) versus normal immortalized breast epithelial cell line (MCF-10A). Thus, DHAQ-97 reduced both viability and proliferation of MCF-7 cells to a much greater extent than did for MCF-10A cells. The growth inhibitory and anti-proliferative properties of DHAQ-97 appear to be attributable to its ability to induce apoptosis as revealed by positive staining after in 냐셔 nick-end labeling (TUNEL), cleavage of poly(ADP-ribose)polymerase, release of mitochondrial cytochrome c into cytoplasm, and increased expression of pro-apoptotic Bax protein. Recent studies have indicated possible involvement of the ubiquitous eukaryotic transcription factor, NF-kappa B (NF-kB) in the regulation of apoptotic cell death. In line induced cytotoxicity in cultured MCF-7 cells. Furthermore, mild activation of NF-kB, as determined by its increased DNA binding capability, was observed 30 min after treatment with 10$\mu\textrm{m}$ DHAQ-97. Taken together, the above findings suggest that DHAQ-97 exerts selective cytotoxicity towards cancer cells through induction of apoptosis, which appears to be regulated by NF-kB.

• Korean Journal of Acupuncture
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• 제38권1호
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• pp.32-42
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• 2021

Objectives : In this study, we investigated the neuroprotective effects of ethanol extract of Lonicera japonica flower buds (EELJ) on glutamate-induced neurotoxicity in mouse hippocampus-derived neuronal HT22 cells. Methods : After analyzing the cytoprotective effect of EELJ on glutamate in HT22 cells, the inhibitory effect of apoptosis was studied using flow cytometry. In order to analyze the antioxidant efficacy of EELJ, the levels of reactive oxygen species (ROS) and glutathione (GSH) were investigated, and the effects on the activities of superoxide dismutase (SOD) and catalase (CAT) were also analyzed. Furthermore, the effect of EELJ on the expression of apoptosis regulators such as Bax and Bcl-2 in glutamate-treated HT22 cells was investigated. Results : According the current results, pretreatment with EELJ significantly reduced glutamate-induced loss of cell viability and release of lactate dehydrogenase. EELJ also markedly attenuated glutamate-induced generation of intracellular ROS, which was associated with increased levels of GSH, and activity of SOD and CAT in glutamate-stimulated HT22 cells. In addition, EELJ was strikingly inhibited glutamate-induced apoptosis in HT22 cells. Furthermore, the expression of pro-apoptotic Bax was increased and the expression of anti-apoptotic Bcl-2 was decreased in glutamate-treated HT22 cells, while in the presence of EELJ, their expressions were maintained at the control levels. Conclusions : These findings indicate that EELJ protects glutamate-induced cytotoxicity in HT22 hippocampal neurons through antioxidant activity. Therefore, although identification of biologically active substances of EELJ and re-evaluation through animal experiments is necessary, this natural substance is a promising candidate for further research in preventing and treating oxidative stress-mediated neurodegenerative diseases.

• Biomolecules & Therapeutics
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• 제24권2호
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• pp.147-155
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• 2016

Chaetominine is a quinazoline alkaloid originating from the endophytic fungus Aspergillus fumigatus CY018. In this study, we showed evidence that chaetominine has cytotoxic and apoptotic effects on human leukemia K562 cells and investigated the pathway involved in chaetominine-induced apoptosis in detail. Chaetominine inhibited K562 cell growth, with an $IC_{50}$ value of 35 nM, but showed little inhibitory effect on the growth of human peripheral blood mononuclear cells. The high apoptosis rates, morphological apoptotic features, and DNA fragmentation caused by chaetominine indicated that the cytotoxicity was partially caused by its pro-apoptotic effect. Under chaetominine treatment, the Bax/Bcl-2 ratio was upregulated (from 0.3 to 8), which was followed by a decrease in mitochondrial membrane potential, release of cytochrome c from mitochondria into the cytosol, and stimulation of Apaf-1. Furthermore, activation of caspase-9 and caspase-3, which are the main executers of the apoptotic process, was observed. These results demonstrated that chaetominine induced cell apoptosis via the mitochondrial pathway. Chaetominine inhibited K562 cell growth and induced apoptotic cell death through the intrinsic pathway, which suggests that chaetominine might be a promising therapeutic for leukemia.

• The Korean Journal of Physiology and Pharmacology
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• 제11권5호
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• pp.163-169
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• 2007

The neurotoxicity of amyloid $\beta(A\beta)$ is associated with an increased production of reactive oxygen species and apoptosis, and it has been implicated in the development of Alzheimer's disease. While(-)-epigallocatechin-3-gallate(EGCG) suppresses $A\beta$-induced apoptosis, the mechanisms underlying this process have yet to be completely clarified. This study was designed to investigate whether EGCG plays a neuroprotective role by activating cell survival system such as protein kinase C(PKC), extracellular-signal-related kinase(ERK), c-Jun N-terminal kinase(JNK), and anti-apoptotic and pro-apoptotic genes in SH-SY5Y human neuroblastoma cells. One ${\mu}M\;A{\beta}_{1-42}$ decreased cell viability, which was correlated with increased DNA fragmentation evidenced by DAPI staining. Pre-treatment of SH-SY5Y neuroblastoma cells with EGCG($1{\mu}M$) significantly attenuated $A{\beta}_{1-42}$-induced cytotoxicity. Potential cell signaling candidates involved in this neuroprotective effects were further examined. EGCG restored the reduced PKC, ERK, and JNK activities caused by $A{\beta}_{1-42}$ toxicity. In addition, gene expression analysis revealed that EGCG prevented both the $A{\beta}_{1-42}$-induced expression of a pro-apoptotic gene mRNA, Bad and Bax, and the decrease of an anti-apoptotic gene mRNA, Bcl-2 and Bcl-xl. These results suggest that the neuroprotective mechanism of EGCG against $A{\beta}_{1-42}$-induced apoptotic cell death includes stimulation of PKC, ERK, and JNK, and modulation of cell survival and death genes.

• Journal of Physiology & Pathology in Korean Medicine
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• 제26권4호
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• pp.441-445
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• 2012

Cadmium is an important occupational and environmental pollutant that damages various organs, especially renal proximal tubular cells. We examined the effect of aqueous extract of Buddleja officinalis (ABO) on cadmium chloride ($CdCl_2$)-induced cytotoxicity in HK-2 human renal proximal tubular cells. HK-2 cells were preincubated with ABO (50, 100, 200 and 400 ${\mu}g/ml$) for 3 hr and then treated with 10 ${\mu}M$ $CdCl_2$ for 24 hr. The effect of ABO on $CdCl_2$-induced cytotoxicity in HK-2 cells was investigated by using MTT assay, morphological observation, flow cytometric analysis and Western blot. The results of the MTT assay and morphological observation indicated that $CdCl_2$-induced cytotoxicity was prevented by pretreatment with ABO. In flow cytometric analysis, ABO reduced sub-G1 peak (apoptotic peak) in $CdCl_2$-treated cells. $CdCl_2$-induced procaspase-3 proteolysis and PARP cleavage reduced by pretreatment with ABO. These results suggest that ABO effectively inhibited $CdCl_2$-induced cytotoxicity in HK-2 cells.

• The Journal of Korean Medicine
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• 제24권2호
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• pp.159-165
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• 2003

Objectives : Coptidis rhizoma (CR) is an oriental medicine that has been used in many traditional prescriptions against diabetes mellitus in Korea for centuries. Our purpose was to determine the protective effect and its action mechanism of CR on the cytotoxicity of pancreatic -cell line (RINm5F cell). Methods : In this experiment, we used methods such as MTT assay for detection of cytotoxicity, DNA fragmentation assay for detection of apoptotic cell death, LDH activity assay for detection of necrotic cell death, and measurement of $DiOC_{6}$ (3) retention for detection of mitochondrial membrane potential (MMP). Background : Nitric oxide (NO) is believed to playa key role in the process of pancreatic -cell destruction leading to insulin-dependent diabetes mellitus (IDDM). Results : Exposure of RINm5F cells to chemical NO donor such as S-nitroso-N-acetylpenicillamine (SNAP) induced cytotoxic events such as DNA fragmentation and lactate dehydrogenase (LDH) release into medium. However, pretreatment of RINm5F cells with CR extract ($10~50{\mu\textrm{g}}/ml$) for 3 hours prevented SNAP-induced DNA fragmentation and LDH release into medium through the inhibition of MMP disruption. Conclusions : These results suggest that CR may be a candidate for a therapeutic or preventing agent against IDDM.