• 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.

• Food Science and Preservation
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• v.30 no.5
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• pp.797-810
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• 2023

Elaeagnus umbellata leaves have been reported to suppress inflammation, allergic responses, lung cancer proliferation and oral bacterial growth. Cadmium (Cd) is a heavy metal that has been found to cause many toxicities, including liver toxicity. The aim of this study was to evaluate the capacity of 70% ethanol extract of E. umbellata leaves (EUL) to protect human hepatocytes from Cd toxicity. After exposure of HepG2 cells to Cd at 10 𝜇M for 24 h, cell viability, expression levels of apoptosis- and antioxidant-related proteins, reactive oxygen species (ROS) accumulation and Cd uptake were assessed. EUL protected HepG2 cells from Cd-induced apoptosis as determined by MTT assay. A decrease in caspase-3 and p-p53 protein levels was observed in cells pretreated with EUL prior to Cd exposure. Furthermore, the Cd-induced increase in intracellular DCF fluorescence was attenuated by EUL, indicating that the Cd-induced apoptosis preventing effect was associated with the suppression of ROS accumulation. Moreover, EUL's effects on the inhibition of p38, JNK, and AKT phosphorylation also appear to be associated with protection against Cd toxicity. Moreover, EUL upregulated Cd-depressed expression of Nrf2, HO-1, catalase, and MT-1,2 proteins, suggesting that Cd uptake-induced apoptosis in HepG2 cells may be inhibited by EUL's antioxidative potential.

• The Journal of Internal Korean Medicine
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• v.31 no.1
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• pp.54-65
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• 2010

Objective : The water extract of Chungsimyeonja-eum (CSYJE) has traditionally been used in treatments of heart diseases and brain diseases in Oriental medicine. However, little is known about the mechanism by which CSYJE protects neuronal cells from injury damages. Therefore, in this study we attempted to elucidate the mechanism of the cytoprotective effect of the CSYJE extract on glutamate-induced C6 glial cell death. Methods : Cultured cells were pretreated with CSYJE and exposed to glutamate, cell damage was assessed by using MTT assay and propidium iodide (PI), probe 2',7'-dichlorofluorescein diacetate (DCF-DA) staining. Western blotting was performed using anti-procaspase-3 and anti-PARP, respectively. Result : We determined the elevated cell viability by CSYJE extract on glutamate-induced C6 glial cell death. Glutamate induced DNA fragmentation on C6 glial cells but pre-treatment with CSYJE inhibited DNA fragmentation. One of the main mediators of glutamate-induced cytotoxicity was known to generation of reactive oxygen species (ROS). Pre-treatment with CSYJE inhibited this ROS generation from glutamate-stimulated C6 glial cells. Also, we identified that the ROS-induced DCF-DA green fluorescence was reduced by CSYJE pre-treatment. The critical markers of apoptotic cell death are the cleavages of procaspase-3 protease and PARP proteins, so we checked the expression level and cleavages of procaspase-3 protease and PARP proteins. Glutamate-treated C6 glial cells showed the cleavages of procaspase-3 protease and PARP proteins and followed the reduction of expression of these proteins. Conclusion : These findings indicate that CSYJE may prevent cell death from glutamate-induced C6 glial cell death by inhibiting the ROS generation and procaspase-3 and PARP expression.

• 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.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.4
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• pp.371-376
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• 2017

The caudal subnucleus of the spinal trigeminal nucleus (medullary dorsal horn; MDH) receives direct inputs from small diameter primary afferent fibers that predominantly transmit nociceptive information in the orofacial region. Recent studies indicate that reactive oxygen species (ROS) is involved in persistent pain, primarily through spinal mechanisms. In this study, we aimed to investigate the role of xanthine/xanthine oxidase (X/XO) system, a known generator of superoxide anion ($O_2{^-}$), on membrane excitability in the rat MDH neurons. For this, we used patch clamp recording and confocal imaging. An application of X/XO ($300{\mu}M/30mU$) induced membrane depolarization and inward currents. When slices were pretreated with ROS scavengers, such as phenyl N-tert-butylnitrone (PBN), superoxide dismutase (SOD), and catalase, X/XO-induced responses decreased. Fluorescence intensity in the DCF-DA and DHE-loaded MDH cells increased on the application of X/XO. An anion channel blocker, 4,4-diisothiocyanatostilbene-2,2-disulfonic acid (DIDS), significantly decreased X/XO-induced depolarization. X/XO elicited an inward current associated with a linear current-voltage relationship that reversed near -40 mV. X/XO-induced depolarization reduced in the presence of $La^{3+}$, a nonselective cation channel (NSCC) blocker, and by lowering the external sodium concentration, indicating that membrane depolarization and inward current are induced by influx of $Na^+$ ions. In conclusion, X/XO-induced ROS modulate the membrane excitability of MDH neurons, which was related to the activation of NSCC.

• Journal of Microbiology and Biotechnology
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• v.25 no.5
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• pp.738-744
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• 2015

Tuberculosis is one of the most threatening infectious diseases to public health all over the world, for which Mycobacterium tuberculosis (MTB) is the etiological agent of pathogenesis. Ursolic acid (UA) has immunomodulatory function and exhibits antimycobacterial activity. However, the intracellular killing effect of UA has yet to be elucidated. The aim of this study was to evaluate the intracellular killing effect of UA during mycobacterial infection. The intracellular killing activity of UA was evaluated in the macrophage cell line THP-1 by the MGIT 960 system as well as by CFU count. The production of reactive oxygen species (ROS) and the level of nitric oxide (NO) were measured using DCF-DA and Griess reagent, respectively. Phagocytosis was observed by a fluorescence-based staining method, and the colony forming units were enumerated on 7H11 agar medium following infection. In addition, MRP8 mRNA expression was measured by qRT-PCR. UA significantly decreased the number of intracellular Mycobacterium through generation of ROS and NO. In addition, it profoundly activated the phagocytosis process of THP-1 cells during MTB-infection. Furthermore, our data demonstrated that UA activated the phagocytosis process in human monocyte cells through MRP8 induction. These data suggest that UA firmly contributes to the intracellular killing effect of macrophages during mycobacterial infection.

• Archives of Pharmacal Research
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• v.27 no.9
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• pp.947-953
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• 2004

The antioxidative and hepatoprotective potentials of two anthraquinones, alaternin (2-hydroxy-emodin) and emodin, to scavenge and/or inhibit hydroxyl radicals generated by the Fenton reaction and to protect tacrine-induced cytotoxicity in human liver derived HepG2 cells were evaluated, respectively. The inhibitory activity on hydroxyl radical generated in a cell-free chemical system (FeSO$_4$/$H_2O$$_2$) was investigated by a fluorescence spectrophotometer using a highly fluorescent probe, 2$^1$,7$^1$-dichlorofluorescein. The hydroxyl radical scavenging activity was determined by electron spin resonance spectroscopy using 5,5-dimethy-1-pyrroline-N-oxide as hydroxyl radicals trapping agents. Tacrine-induced HepG2 cell toxicity was determined by a 3-［4,5-dimethylthiazole-2yl］-2,5-diphenyltertrazolium bromide assay. Although the scavenging activity of alaternin on hydroxyl radical was similar to that of emodin in dose-dependent pat-terns, the inhibitory activity exhibited by the former on hydroxyl radical generation was stron-ger than that of the latter, with $IC_{50}$/ values of 3.05$\pm$0.26 $\mu$M and 13.29$\pm$3.20 $\mu$M, respectively. In addition, the two anthraquinones, alaternin and emodin showed their hepatoprotective activ-ities on tacrine-induced cytotoxicity, and the EC$_{50}$ values were 4.02 11M and 2.37 $\mu$M, respec-tively. Silymarin, an antihepatotoxic agent used as a positive control exhibited the EC$_{50}$ value of 2.00 $\mu$M. These results demonstrated that both alaternin and emodin had the simultaneous antioxidant and hepatoprotective activities.ies.

• Reproductive and Developmental Biology
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• v.35 no.2
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• pp.191-195
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• 2011

The present study was conducted to examine the reactive oxygen species (ROS) generation levels in porcine parthenogenetic embryos. Porcine in vitro matured oocytes were activated by the combination of electric stimulus and 6-DMAP before in vitro culture. Porcine oocytes and parthenogenetic embryos were stained in 10 ${\mu}M$ dichlorohydrofluorescein diacetate (DCF) or 10 ${\mu}M$ hydroxyphenyl fluorescein (HPF) dye each for 30 min at $39^{\circ}C$. The fluorescent emissions from the samples were recoded as JPEG file and the intensity of fluorescence in oocytes and embryos were analyzed. $H_2O_2$ and $^{\cdot}OH$ radical levels of porcine oocytes were reduced immediately after electric stimulation. However, $H_2O_2$ and $^{\cdot}OH$ radical levels of parthenogenetic embryos were increased with time elapsed after electric stimulation from 0 h to 3 h and after DMAP culture. During in vitro culture, $H_2O_2$ and $^{\cdot}OH$ radical levels were gradually increased from the one-cell stage to the two- and four-cell stages. The result of the present study suggests that the ROS was not increased by electric pulse in porcine embryos. Rather than it seems to be associated with the stage of development and the culture condition.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.32 no.2 s.57
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• pp.69-74
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• 2006

Selaginella tamariscina with the popular Korean name Keoun Back, is a traditional medicinal plant for therapy of advanced cancer patients in the Orient. In this study, we evaluated anti-aging activity of S. tamariscina using processed technology and investigated diverse biological activities of processed S. tamariscina (PST) as an anti-aging ingredient of cosmetics. PST, heated with sand, used to different purpose compared with origin in medicine. PST raises total phenol concentration and enhances the DPPH radical scavenging activity. For testing intracellular ROS scavenging activity, the cultured human dermal fibroblasts were analyzed by increase in dichlorofluorescein (DCF) fluorescence upon exposure to UVB $20 mJ/cm^2$ after treatment of PST. UVA-induced MMP-1 expression in human dermal fibroblasts was reduced in a dose-dependent manner by PST. Taken together, 4hese results suggest that PST may act as an anti-aging agent by preventing the skin cell from damage induced by UV irradiation, and imply that PST may be useful as a new ingredient for anti-aging cosmetics.