• Journal of dental hygiene science
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• v.13 no.3
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• pp.321-329
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• 2013

Although it has been reported that lysyl oxidase (LOX) is involved in odontoblastic differentiation, the role of LOX on odontoblastic differentiation by hydrogen peroxide ($H_2O_2$) have not been clarified. In the present study, we investigated whether $H_2O_2$, reactive oxygen species (ROS), is modulated the messenger RNA (mRNA) expression and activity of LOX during odontoblastic differentiation of human dental pulp (HDP) cells. The mRNA expression was quantified by reverse transcriptase polymerase chain reaction (RT-PCR) analysis, and LOX enzyme activity was measured by high sensitive fluorescent assay. Expression of the odontoblastic differentiation marker genes were assessed in the presence and absence of specific small interfering RNAs (siRNAs) of the LOX and LOXL. The $H_2O_2$-induced mRNA expression of LOX family was significant reduction of LOX, LOXL, and LOXL3 mRNA levels in HDP cells. LOX enzyme activity was increased at $H_2O_2$ 0.3 mM for 24 hours. The mRNA expression of alkaline phosphatase (ALP), osteopontin (OPN), and osteocalcin (OCN) was inhibited by LOX- and LOXL-specific siRNAs whereas the mRNA expression of dentin matrix protein1 (DMP1), and dentin sialophosphoprotein (DSPP) was inhibited by LOX-specific siRNA. In LOX enzyme activity, siRNA-induced knockdown of both LOX and LOXL inhibited the total amine oxidase activity in HDP cells, as in the case of mRNA expression. In conclusion, the essential role of $H_2O_2$ on odontoblastic differentiation suggests that its regulation by LOX may have pharmacologic importance in HDP cells.

• Journal of Life Science
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• v.23 no.3
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• pp.462-469
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• 2013

Withaferin A is a steroidal lactone purified from the Indian medicinal plant Withania somnifera. It exhibits a wide variety of activities, including anti-tumor, anti-inflammation, and immunomodulation properties. In this review, we focused on the anti-cancer effects of withaferin A. Withaferin A inhibits cell proliferation, metastasis, invasion, and angiogenesis in cancer cells. Furthermore, it sensitized irradiation, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-, and doxorubicin-mediated apoptosis. The results showed that multiple mechanisms were involved in withaferin A-mediated anti-cancer effects. First, withaferin A increased intracellular reactive oxygen species (ROS) production and induced ER stress- and mitochondria-mediated apoptosis. Second, withaferin A inhibited the signaling pathways (Jak/STAT, Akt, Notch, and c-Met), which are important in cell survival, proliferation, and metastasis. Third, it induced apoptosis and inhibited cancer cell migration through the up-regulation of prostate apoptosis protein-4 (Par-4). Finally, withaferin A up-regulated pro-apoptotic protein expression levels through the inhibition of proteasome activity. Our findings suggested that withaferin A is a potential, potent therapeutic agent.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.39 no.4
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• pp.313-322
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• 2013

Ultraviolet irradiation in the cells and skin produces reactive oxygen species (ROS), which induces the synthesis of matrix metalloproteinases (MMPs) causing skin photoaging. Using the human dermal fibroblast (HDF), we investigated the antioxidative and anti-aging effects of the extracts from Talinum paniculatum. Talinum paniculatum leaf and stem extracts (LSE) showed free radical scavenging effect by 98.45% at 500 ${\mu}g/mL$ and superoxide radical scavenging effect by 97.01% at 500 ${\mu}g/mL$ in the xanthine/xanthine oxidase system. The photoprotective potential of LSE was tested in HDF exposed to ultraviolet irradiation. It was revealed that LSE had an inhibitory effect on MMP-1 expression in UVA-irradiated HDF without any significant cytotoxicity. The treatment of UVA-irradiated HDF with LSE resulted in dose-dependent decreases in the expression levels of MMP-1 mRNA and protein. Also, UVB-induced cytotoxicity and cell death were effectively suppressed by treatment of LSE. Additionally, the senescence-associated ${\beta}$- galactosidase (SA-${\beta}$-gal) activity was decreased in the presence of LSE. These results suggest that Talinum paniculatum leaf and stem extracts (LSE) may have anti-aging effects and can be used as new functional materials against oxidative stress-mediated skin damages.

• BMB Reports
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• v.37 no.4
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• pp.454-459
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• 2004

Experimental hyperoxia represents a suitable in vitro model to study some pathogenic mechanisms related to oxidative stress. Moreover, it allows the investigation of the molecular pathophysiology underlying oxygen therapy and toxicity. In this study, a modified experimental set up was adopted to accomplish a model of moderate hyperoxia (50% $O_2$, 96 h culture) to induce oxidative stress in the human leukemia cell line, U-937. Spectrophotometric measurements of mitochondrial respiratory enzyme activities, NMR spectroscopy of culture media, determination of antioxidant enzyme activities, and cell proliferation and differentiation assays were performed. The data showed that moderate hyperoxia in this myeloid cell line causes: i) intriguing alterations in the mitochondrial activities at the levels of succinate dehydrogenase and succinate-cytochrome c reductase; ii) induction of metabolic compensatory adaptations, with significant shift to glycolysis; iii) induction of different antioxidant enzyme activities; iv) significant cell growth inhibition and v) no significant apoptosis. This work will permit better characterization the mitochondrial damage induced by hyperoxia. In particular, the data showed a large increase in the succinate cytochrome c reductase activity, which could be a fundamental pathogenic mechanism at the basis of oxygen toxicity.

• Food Science and Preservation
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• v.22 no.5
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• pp.751-757
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• 2015

The objective of this study was to investigate the protective effects of mulberry (Morus alba) sugar extracts (MSE) against $H_2O_2$-induced oxidative stress in HepG2 cells. The MSEs was mixed with matured mulberry and sugar at the same ratio (1:1, w/w) and stored at $18{\pm}3^{\circ}C$ for 40 days. In 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging test, MSE stored for 40 days showed high activity with a ratio above 66%. Therefore, we selected 40 days as the optimum storage period. After cell viability analysis using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, we determined that the optimum concentration of MSE was 0.5%. Our results showed that MSE increased the cell viability and antioxidant enzyme activities of superoxide dismutase (SOD) and catalase in $H_2O_2$-treated HepG2 cells. Moreover, the treatment with MSE inhibited malondialdehyde (MDA) levels in $H_2O_2$-treated HepG2 cells. We also observed a reduction in apoptotic bodies in the Hoechst staining. These data show that MSE treatment significantly suppressed caspase-3 activity in HepG2 cells expored to $H_2O_2$-induced oxidative stress, thereby indicationg the protective effects of MSE in $H_2O_2$-induced oxidative stress.

• Molecules and Cells
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• v.40 no.8
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• pp.567-576
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• 2017

The $Na^+/H^+$ exchanger is responsible for maintaining the acidic tumor microenvironment through its promotion of the reabsorption of extracellular $Na^+$ and the extrusion of intracellular $H^+$. The resultant increase in the extracellular acidity contributes to the chemoresistance of malignant tumors. In this study, the chemosensitizing effects of cariporide, a potent $Na^+/H^+-exchange$ inhibitor, were evaluated in human malignant mesothelioma H-2452 cells preadapted with lactic acid. A higher basal level of phosphorylated (p)-AKT protein was found in the acid-tolerable H-2452AcT cells compared with their parental acid-sensitive H-2452 cells. When introduced in H-2452AcT cells with a concentration that shows only a slight toxicity in H-2452 cells, cariporide exhibited growth-suppressive and apoptosis-promoting activities, as demonstrated by an increase in the cells with pyknotic and fragmented nuclei, annexin V-PE(+) staining, a $sub-G_0/G_1$ peak, and a $G_2/M$ phase-transition delay in the cell cycle. Preceding these changes, a cariporide-induced p-AKT down-regulation, a p53 up-regulation, an ROS accumulation, and the depolarization of the mitochondrial-membrane potential were observed. A pretreatment with the phosphatidylinositol-3-kinase (PI3K) inhibitor LY294002 markedly augmented the DNA damage caused by the cariporide, as indicated by a much greater extent of comet tails and a tail moment with increased levels of the p-histone H2A.X, $p-ATM^{Ser1981}$, $p-ATR^{Ser428}$, $p-CHK1^{Ser345}$, and $p-CHK2^{Thr68}$, as well as a series of pro-apoptotic events. The data suggest that an inhibition of the PI3K/AKT signaling is necessary to enhance the cytotoxicity toward the acidtolerable H-2452AcT cells, and it underlines the significance of proton-pump targeting as a potential therapeutic strategy to overcome the acidic-microenvironment-associated chemotherapeutic resistance.

• Korean Journal of Food Science and Technology
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• v.41 no.1
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• pp.87-92
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• 2009

The antioxidant properties and protective effects of Inula britannica on ${H_2}{O_2}$-induced SH-SY5Y neuroblastoma cell damage were investigated. A series of solvent fractions, including hexane(Fr.H), petroleum ether, chloroform, ethyl acetate(Fr.EA), and water fraction(Fr.W), were prepared from the 70% methanol extracts of Inula britannica. Fr.W had the highest total contents of phenolics and flavonoids, followed by Fr.EA. The antioxidant properties of the fractions were also evaluated by analyzing their scavenging activities on 1,1-diphenyl-2-picrylhydrazyl(DPPH) radicals, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals, and nitric oxide. Fr.W showed the strongest activities in all assays. The concentrations of Fr.W that resulted in 50% reductions of the DPPH and ABTS radicals were 20.7 ${\mu}g$/mL and 39.4 ${\mu}g$/mL, respectively. Fr.W showed the weakest cytotoxic activities on the SH-SY5Y cells, whereas it effectively protected ${H_2}{O_2}$-induced cell death, increasing cell survival by 35.0-77.0% at a concentration range of 62.5-250 ${\mu}g$/mL. In this range, Fr.W also significantly decreased intracellular ROS levels by 34-39%. Overall, the antioxidant properties of Inula britannica can contribute to rescuring neuronal cells from oxidative stress-induced cell injury.

• Journal of Physiology & Pathology in Korean Medicine
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• v.29 no.1
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• pp.18-26
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• 2015

Akebiae Caulis is a galenical originated from Akebia quinata Decaisne species. It is commonly used in the treatment of oposiuria, inflammation, nociceptive and fever. Here, we investigated the effect of Akebiae Caulis extract (ACE) to protect hepatocyte against the malfunction of mitochondria and apoptosis. Arachidonic acid (AA)+iron promoted excessive reactive oxygen species (ROS) production and exerted a deleterious effect on mitochondria. Treatment with ACE protected hepatocytes from AA+iron-induced cytotoxicity, as shown by alterations in the protein levels related with apoptosis such as poly(ADP-ribose) polymerase, pro-caspase 3, Bcl-XL and Bcl-2. Moreover, AA+iron-induced $H_2O_2$ production, GSH depletion and mitochondrial dysfunction were alleviated by ACE pretreatment. As a potential molecular mechanism for the ACE-mediated cytoprotection, phosphorylation of AMP-activated protein kinase (AMPK), a key regulator in determining cell survival or death, was increased by ACE. Moreover, ACE treatment enhanced inactive phosphorylation of glycogen synthase kinase-$3{\beta}$ ($GSK3{\beta}$), downstream substrate kinase of AMPK. More importantly, ACE prevented a decrease in the $GSK3{\beta}$ phosphorylation derived by AA+iron, which might contribute to mitohondiral protection and cell survival. To further identify essential compounds in Akebiae Caulis for the protection of AA+iron-mediated cytotoxicity, we found that betulin in combination with hederagenin protected from AA+iron-induced mitochondrial dysfunction. Betulin+hederagenin treatment also increased inactive phosphorylation of $GSK3{\beta}$ in common with ACE. These results suggest that ACE protected hepatocytes against oxidative stress and mitochondrial dysfunction, which is mediated with inactive $GSK3{\beta}$ phosphorylation downstream of AMPK.

• Journal of Life Science
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• v.29 no.9
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• pp.977-985
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• 2019

Aster yomena (Kitam.) Honda is an edible vegetable and perennial herb belonging to the Asteraceae family, and has been used for a long time for the prevention and treatment of various diseases. Although leaf extracts of A. yomena are known to have antioxidant and anti-inflammatory effects, accurate efficacy assessments are still inadequate. In this study, we investigated whether the antioxidant efficacy of ethanol extract of A. yomena leaf (EEAY) is correlated with the anti-inflammatory effect in RAW 264.7 macrophages. The results showed that EEAY significantly inhibited the hydrogen peroxide ($H_2O_2$)-induced growth inhibition in RAW 264.7 cells, which was associated with increased expression of nuclear factor erythroid 2-related factor-2 (Nrf2) and heme oxygenase-1 (HO-1). EEAY pretreatment also effectively prevented $H_2O_2$-induced reactive oxygen species generation and apoptosis through inhibition of caspase-3 activation and poly (ADP-ribose) polymerase degradation. Additionally, EEAY significantly increased the expression and production of interleukin-10, a representative anti-inflammatory cytokine, which was associated with increased expression of toll-like receptor 4 and myeloid differentiation factor 88 at transcriptional and translational levels. Furthermore, the increased production of nitric oxide (NO) by lipopolysaccharide was markedly abolished under the condition of EEAY pretreatment, and the inhibitory effect of NO production by EEAY was further increased by hemin, an HO-1 inducer. Overall, our results suggest that EEAY is able to activate the Nrf2/HO-1 signaling pathway to protect RAW 264.7 macrophages from oxidative and inflammatory stress.

• Korean Journal of Medicinal Crop Science
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• v.27 no.2
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• pp.115-125
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• 2019

Background: Glycyrrhiza radix (licorice root) have been used as an oriental medicine material for long time, and its protective effects on oxidative stress, inflammation and cognition deficit have been recently reported. However, the cultivation of Glycyrrhiza species as medicinal crops is associated with some problems such as low productivity and early leaf fall, etc. To resolve this problems, Glycyrrhiza cultivars have been developed by direct hybridization of each Glycyrrhiza species by Korean researchers. The present study was conducted to compare the Glycyrrhiza cultivar radix (Dagam, Sinwongam and Wongam) for their anti-oxidation, anti-inflammation, and cognition improvement effects and levels of liquiritin, isoliquiritigenin and licochalcone in order to select an excellent cultivar as a material resource. Methods and Results: For evaluating the inhibitory efficacies of the Glycyrrhiza cultivar extracts on oxidative stress and inflammation in BV2 cells, we measured their reactive oxygen species (ROS) production and nitric oxide (NO) release after treating them with lipopolysccharide. The scavenging activities on 2,2-diphenyl-1-picrylhydrazyl (DPPH) and peroxynitrite ($NOO^-$) radicals were evaluated. Cell proliferation and N-methyl-D-aspartate receptor (NMDAR) inhibition were analyzed. The total phenol, liquiritin, isoliquiritigenin and licochalcone A content in the extracts of the three culivars were quantified. Furthermore, the correlation coefficient between the activities and contents of total phenol, liquiritin, isoliquiritigenin and licochalcone A were also calculated. The results indicated that Sinwongam exhibited potent anti-oxidant, anti-inflammatory and NMDAR inhibititory activities. Sinwongam also showed higher total phenol and licochalcone A contents than the other cultivars. Among the three cultivars, Dagam exhibited a positive effects on NO release inhibition, cell proliferation and contents of liquiritin and isoliquiritigenin. Conclusions: Sinwongam is expected to be the most useful resource as a functional material for anti-oxidation/anti-inflammation and cognition improvement among the three studied licorice cultivars.