• Natural Product Sciences
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• v.18 no.1
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• pp.26-31
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• 2012

Actinidia arguta (Actinidiaceae) has been reported to have several pharmacological effects such as anti-inflammatory, anti-allergic, and anti-oxidant activities. The present study investigated the protective activity of an ethanol extract from the leaf and stem of A. arguta against glutamate-induced neurotoxicity using cultured rat cortical neurons. Exposure of cultured cortical neurons to $500{\mu}M$ glutamate for 12 h triggered neuronal cell death. A. arguta inhibited glutamate-induced neuronal death and apoptosis, which were measured by a 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay and Hoechst 33342 staining, respectively. The increase of pro-apoptotic proteins, Bax and c-caspase-3, in glutamate-treated neurons was significantly inhibited by treatment with A. arguta. A. arguta also inhibited $500{\mu}M$ glutamate-induced elevation of intracellular calcium concentration ($[Ca^{2+}]_i$) and reactive oxygen species (ROS) generation, which were measured by fluorescent dyes, Fluo-4 AM and $H_2DCF$-DA, respectively. These results suggest that A. arguta may prevent glutamate-induced apoptotic neuronal death by inhibiting $[Ca^{2+}]_i$ elevation and ROS generation and, therefore, may have a therapeutic role for the prevention of neurodegeneration in cerebral ischemic diseases.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.261.2-261.2
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• 2014

저온에서 작동하는 대기압 플라즈마 젯은 생체 조직에의 플라즈마 처리를 가능하게 한다. 이에 이온과 전자, 활성 종, 전기장, UV 등을 발생시키는 플라즈마를 암세포에 처리하여 그에 따른 변화를 관찰하였다. 모세관 타입의 젯에 산소를 반응기체로 흘려주어 헬륨 내 산소 함유량에 따른 활성 산소종의 생성을 확인하였다. 대기압 플라즈마에 의해 생성되는 활성 산소 종(OH, O, electronically excited O (1D), O2 ($1{\Delta}g$) 등)이 세포에 산화 스트레스를 유발할 것이라 예상되어 인체의 폐암 세포[Human lung cancer cell, A549]에 펄스파의 헬륨-산소 플라즈마를 처리한 후, 세포 내 활성 산소 종의 증가량을 비교하였다. 그 결과 적은 양의 산소를 추가하였을 때 세포 내 활성 산소 종의 농도가 증가되었다. 이때 플라즈마에서 발생되는 활성 산소 종(Reactive Oxygen Species, ROS)들은 광 방출 스펙트럼(Optical Emission Spectroscopy)로 확인하였고, 세포내 활성 산소 종은 DCF-DA 염색을 통하여 분석하였다. 이러한 헬륨-산소 플라즈마가 세포 성장의 어떠한 시기에 영향을 미치는지를 알아보기 위하여 세포주기 변화를 분석한 결과, 플라즈마 처리 9시간 후부터 G2/M 주기에 머물러 있음을 확인하였다.

• The Journal of Korean Medicine
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• v.25 no.3
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• pp.90-98
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• 2004

Objectives : The present study was undertaken to investigate the molecular mechanisms of Ichungwhan for inhibition of cyclooxygenase-2 (COX-2) gene expression via suppression of NF-κB (nuclear factor κB) using aged rats. NF-κB is the most important modulator of inflammation and NF-κB regulates the gene expression of several pro-inflammatory cytokines, such as COX-2. Methods : In the experiment, we investigated the scavenging property of Ichungwhan on reactive species (RS) including nitrogen-derived species (RNS), measured by DCF-DA (2,7-dichlorodihydrofluorexcein diacetate) / DHR 123 (dihydrorhodamine 123) assay. Protein expression levels of COX-2, NF-κB, p-ERK and p-p38 were assayed by western blot. Results : We showed that Ichungwhan inhibits RS including RNS and inhibits NF-κB activation by blocking the dissociation of inhibitory IκB-β via suppression of IKK pathway. Also, Ichungwhan inhibits COX-2 gene expression. Conclusions : These findings suggest that Ichungwhan modulates COX-2 gene expression via suppression of the NF-κB pathway.

• Korean journal of food and cookery science
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• v.28 no.6
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• pp.821-828
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• 2012

In an attempt to identify the neuroprotective effect of Cudrania tricuspidata (CT) leaves against ROS (reactive oxygen species)-induced oxidative stress in neuronal cells, the extracts from CT leaves were investigated using PC12 cells and N18-RE-105 cells. The methanolic and ethanolic extracts from CT were denoted as CTM (Cudrania tricuspidata Leaves methanolic extracts) and CTE (Cudrania tricuspidata Leaves ethanolic extracts), respectively. The neuroprotective effects of the extracts were measured by DCF-DA assay, MTT reduction assay, and LDH release assay. The PC12 cells exposed to $H_2O_2$-induced oxidative stress and the N18-RE-105 cells exposed to glutamate-induced oxidative stress were treated with various concentrations of CTM and CTE. The results, CTM treatments resulted in the induction of a dose-dependent protective effect in PC12 cells and N18-RE-105 cells. Interestingly, CTE also showed neuroprotective effect in PC12 cells and N18-RE-105 cells. Therefore, these results suggest that CTM and CTE could be a new potential candidate as neuroprotective agents against ROS-induced oxidative stress in neuronal cells.

• Journal of Life Science
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• v.18 no.3
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• pp.311-317
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• 2008

Pathophysiological oxidative stress results in neuronal cell death mainly due to the generation reactive oxygen species (ROS). In low oxygen situation such as hypoxia and ischemia, excessive ROS is generated. Coptidis Rhizoma (CR) is a traditional medicine used for the incipient stroke. In this report we show that CR water extracts $(1\;{\mu}g/ml)$ exhibited protective effects of neuronal cell death in a hypoxic model (2% $O_2/5%\;CO_2,\;37^{\circ}C,$ 3 hr) of cultured rat cortical cells. We further show that CR water extracts significantly reduced the intensity of green fluorescence after staining with $H_2DCF-DA$ on one hour and three days after hypoxic shock and in normoxia as well. Our results indicate that CR water extracts prevent neuronal death by suppressing ROS generation.

• Biomedical Science Letters
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• v.28 no.1
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• pp.25-33
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• 2022

The imbalance of oxidative stress due to the excessive production of reactive oxygen species (ROS) leads to the pathogenesis of liver disease. To prevent this, the role of antioxidant mechanisms is important. Antioxidant studies have been reported on the Filipendula glaberrima Nakai. However, studies applied to HepG2 cells, which are human liver cells, have not yet been conducted. In this study, 70% ethanol extract of Filipendula glaberrima Nakai (FGE) was prepared and antioxidant activity was investigated. It was confirmed whether FGE pretreatment could reduce hydrogen peroxide-induced oxidative stress in HepG2 cells. The increase in gene expression of antioxidant biomarkers and the scavenging ability of ROS were measured, and Hoechst 33342 staining was used to know the inhibitory effect of the apoptosis. As a result, FGE significantly increased SOD (2.6-fold), CAT (4.4-fold), MT-1A (3.1-fold), GPx (4-fold), and G6PD (2.4)-fold compared to the H₂O₂-treated group. FGE directly inhibited ROS production from 13.4 to 3.6 (the fluorescence mean of DCF-DA) and also reduced apoptotic cells from 45% to 10% (Hoechst 33342 staining) at 2.5 ㎍/mL. These results demonstrate the excellent antioxidant activity of FGE and show that it can be used as a functional food to prevent liver disease.

• Parasites, Hosts and Diseases
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• v.61 no.4
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• pp.388-396
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• 2023

Entamoeba histolytica is an enteric tissue-invasive protozoan parasite causing amoebic colitis and liver abscesses in humans. Amoebic contact with host cells activates intracellular signaling pathways that lead to host cell death via generation of caspase-3, calpain, Ca²⁺ elevation, and reactive oxygen species (ROS). We previously reported that various NADPH oxidases (NOXs) are responsible for ROS-dependent death of various host cells induced by amoeba. In the present study, we investigated the specific NOX isoform involved in ROS-dependent death of hepatocytes induced by amoebas. Co-incubation of hepatoma HepG2 cells with live amoebic trophozoites resulted in remarkably increased DNA fragmentation compared to cells incubated with medium alone. HepG2 cells that adhered to amoebic trophozoites showed strong dichlorodihydrofluorescein diacetate (DCF-DA) fluorescence, suggesting intracellular ROS accumulation within host cells stimulated by amoebic trophozoites. Pretreatment of HepG2 cells with the general NOX inhibitor DPI or NOX2-specific inhibitor GSK 2795039 reduced Entamoeba-induced ROS generation. Similarly, Entamoeba-induced LDH release from HepG2 cells was effectively inhibited by pretreatment with DPI or GSK 2795039. In NOX2-silenced HepG2 cells, Entamoeba-induced LDH release was also significantly inhibited compared with controls. Taken together, the results support an important role of NOX2-derived ROS in hepatocyte death induced by E. histolytica.

• Tuberculosis and Respiratory Diseases
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• v.43 no.5
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• pp.728-735
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• 1996

Background : Recognition and ingestion of opsonized microorganisms by neutrophils induces the burst of oxidative metabolic activity. Products of the respiratory burst activity provide powerful oxygen dependent killing mechanism. Measurement of respiratory burst activity has been a major indicator of the functional capacity of neutrophils. We determined the respiratory burst activity of neutrophils in patients with pneumonia and observed the changes during the clinical course of pneumonia. Methods: The EDTA blood was drawn from 24 normal controls and same numbers of pneumonia patients. The respiratory burst activity(with the production of $H_2O_2$ which changes nonfluorescent DCF-DA to green fluorescent DCF) in the non-stimulated state and the stimulated state with fMLP and PMA of neutrophils was measured by flowcytometry at day 1, 3, 5, 7 and 9 of admission. Results: The respiratory burst activity of neutrophils was mildly increased by stimulation with fMLP. But there was no statistical significance between normal control and patients with pneumonia. The respiratory burst activity of neutrophils was markedly increased by stimulation with PMA in both groups. There was a significant difference in response to PMA between normal control and patients with pneumonia. The production of hydrogen peroxide from neutrophils was decreased during early course of pneumonia and it was recuperated gradually to normal level in 9 days. Conclusion : Hydrogen peroxide production from neutrophils was suppressed during early course of pneumonia and restored after treatment. It is suggested that the production of oxygen radical in response to PMA stimulation from each neutrophils is decreased rather than increased during the early course of pneumonia.

• Journal of Society of Preventive Korean Medicine
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• v.16 no.2
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• pp.95-111
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• 2012

Objective : The water extract of Danguiyonghoihwan (DGYHW) has been traditionally used in treatment of tinnitus in Oriental Medicine. However, little is known about the mechanism by which DGYHW rescues auditory neuronal cells from injury damages. Therefore, in this study I effort to elucidate the mechanism of the cytoprotective effect of the DGYHW extract on glutamate-induced auditory sensorineuronal cell death. Methods : I determined the elevated cell viability by DGYHW extract on glutamate-induced auditory sensorineuronal cell death. Glutamate induced neuronal damage in oranotypic explant culture also, glutamate decreased cell viability on VOT-33 cells but pretreatment with DGYHW inhibited cell death. Results : One of the main mediator of glutamate-induced cytotoxicity was known to generation of reactive oxygen species (ROS). Pretreatment with DGYHW inhibited this ROS generation from glutamated-stimulated VOT-33 cells. Also, I identified that the ROS-induced DCF-DA green fluorescence is reduced by DGYHW pretreatment. The critical markers of apoptotic cell death were cleavages of procaspase-3 protease protein. So I checked the expression level and cleavage of procaspase-3 protease protein. Glutamate-treated VOT-33 cells were shown to have cleavage of procaspase-3 protease proteins and following reduction of expression of these proteins. But I found that pre-treatment with DGYHW protects glutamate-induced changes of biochemical marker protein, caspase-3. Conclusion : These findings indicated that DGYHW may prevent cell death from glutamate induced VOT-33 cell death by inhibiting the ROS generation and modulation of protein expressions in procaspase-3, catalase and Bcl-2.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.1
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• pp.24-30
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• 2011

The anti-cancer effects of Angelica keiskei ethanol extract were evaluated in human breast cancer MDA-MB-231 cells. The concentrations of extract were 1, 2, 3, 4 and 5 mg/mL. Dose-dependent reductions in the number of cells with altered cell shape and pyknotic nuclei were observed at 48 h after treatments. MTT assay also exhibited a similar dose-dependent reduction in mitochondrial reductase activity (p<0.05), in particular, with a rapid reduction in the activity of the 5 mg/mL group. Analysis of cell death with propidium iodide (PI) staining revealed only a slight increase in cell death in the 5 mg/mL group. Analysis of bromodeoxyuridine (BrdU) incorporations also showed a dose-dependent reduction in cell proliferation (p<0.05). Finally, increases in total radical oxygen species (ROS) accumulation in cells, as revealed by DCF-DA staining, were observed in the treated groups in a similar dose-dependent fashion (p<0.05). These results indicate that Angelica keiskei ethanol extract exhibiting anti-cancer effects in MDA-MB-231 cells causes multiple changes in cell shape, enzyme activity, and ROS accumulation, thereby inducing cell death.