• Toxicological Research
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• v.25 no.4
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• pp.181-188
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• 2009

Uncontrolled cell growth and increased cell proliferation are major features of cancer that are dependent on the stable structure and dynamics of the cytoskeleton. Since stable cytoskeleton structure and dynamics are partly regulated by myosin light chain kinase (MLCK), many current studies focused on MLCK inhibition as a chemotherapeutic target. As a potent and selective MLCK inhibitor, ML-7 [1-(5-iodonaphthalene-1-sulfonyl)-1 H-hexahydro-1,4-diazapine hydrochloride] is a promising candidate for an anticancer agent, which would induce apoptosis as well as prevents invasion and metastasis in certain types of cancer cells. This study assessed cytotoxic effects of ML-7 against HL-60 cells and therapeutic efficacy of ML-7 as a potential antileukemia agent. Trypan-blue exclusion assays showed dose- and time- dependent decreases in ML-7 treated HL-60 cells (p<0.05). Comet assays revealed a significant increase in DNA damage in HL-60 cells after treatment with $40{\mu}M$ ML-7 for 2h. Sub-G1 fractions, analyzed by flow cytometry increased in a dose-dependent manner, suggesting that ML-7 can induce apoptotic cell death in HL-60 cells. ML-7 was selectively cytotoxic towards HL-60 cells; not affecting normal human lymphocytes. That selective effect makes it a promising potential anti-leukemia agent. In addition, anticancer efficacy of ML-7 in combination with flavonoids (genistein or quercetin) or anticancer drugs (cisplatin or Ara-C) against HL-60 cells was assessed. Combination of ML-7 with flavonoids increased the anti-cancer effect of ML-7 to a greater extent than combination with the anticancer drugs. This implies that ML-7 in combination with flavonoids could increase the efficacy of anticancer treatment, while avoiding side effects cansed by conventional anticancer drug-containing combination chemotherapy.

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.4
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• pp.487-493
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• 2010

The purpose of this study was to evaluate antioxidant and antigenotoxic effects of Omija (Schizandra chinensis B.) extracted with various solvents (acetone, ethanol, and methanol). The total polyphenol content (TPC) of methanol extract (ME), ethanol extract (EE) and acetone extract (AE) from Omija were 1183.3, 1009.4, and 747.3 mg/100 g (garlic acid equivalents: GAE), respectively. Antioxidant effects of the Omija extracts was measured by DPPH radical-scavenging activity (RSA) and superoxide dismutase (SOD)-like activity. The $IC_{50}$ for DPPH RSA was in the order of EE $(1411.1\;{\mu}g/mL)$=AE $(1462.0\;{\mu}g/mL)$>ME $(1585.0\;{\mu}g/mL)$. The $IC_{50}$ for SOD-like activities was the highest in ME $(905.7\;{\mu}g/mL)$=EE $(970.3\;{\mu}g/mL)$>AE $(1579.4\;{\mu}g/mL)$. The antigenotoxic effect of Omija on DNA damage induced by $H_2O_2$ in human leukocytes was evaluated by comet assay. $H_2O_2$ induced DNA damage was effectively protected by all of the Omija extracts. Aectone extract of Omija showed the highest antigenotoxic effect ($IC_{50}$ value of AE is $14.6\;{\mu}g/mL$) followed by EE, and ME (21.4 and $34.4\;{\mu}g/mL$), respectively. As a result, we propose that Omija (Schizandra chinensis B.) can serve as a new natural source enriched with potent antioxidant and antigenotoxic agents.

• Journal of Applied Biological Chemistry
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• v.58 no.4
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• pp.325-332
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• 2015

Rapeseed (Brassica napus) is now the second largest oilseed crop after soybean. Cold temperature tolerance is an important agronomic trait in winter rapeseed that determines the plant's ability to control below freezing temperatures. To improve cold tolerance of rapeseed plants, an expression vector containing an Barley Ice recrystallization inhibition protein (HvIRIP) cDNA driven by a cauliflower mosaic virus 35S promoter was transferred into rapeseed plants. Transgenic expression of HvIRIP was proved by southern- and northern-blot analyses. The level of freezing tolerance of transgenic $T_3$ plants was found to be significantly greater than that of wild-type rapeseed plants by freezing assay. Proline accumulation during cold stress was also highly induced in the transgenic rapeseed plants. The transgenic plants exhibited considerable tolerance against oxidative damage induced by cold stress. Our results indicated that heterologous HvIRIP expression in transgenic rapeseed plants may induce several oxidative-stress responsive genes to protect from cold stress.

• The Korea Journal of Herbology
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• v.29 no.6
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• pp.63-71
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• 2014

Objectives : Lonicerae japonicae Flos(LJF) has been reported to exhibit anti-oxidant, anti-inflammatory, anti-viral, anti-rheumatoid properties. However, it is still largely unknown whether LJF inhibits the ultraviolet(UV)B-induced oxidative damage in human HaCaT keratinocytes. Therefore in this paper, we investigated the anti-oxidative capacity and protective effect of LJF against UVB-induced oxidative demage in human HaCaT keratinocytes. Methods : To evaluate the anti-oxidative activity of LJF extracts, we measured total phenolic contents, total flavonoid contents, antioxidant capacity, and superoxide scavenging activity. To give an oxidative stress to HaCaT cells, UVB was irradiated with $200mJ/cm^2$ to HaCaT cells. To detect the protective effect of LJF against UVB, we measured cell viability, DNA fragmentation and reactive oxygen species (ROS) production. In addition, we performed high-performance liquid chromatography (HPLC) analysis to find a major component of LJF. Results : LJF contained phenolic and flavonoid contents, and showed the anti-oxidant and superoxide scavenging activity. The UVB-induced oxidative conditions led to the cell death, DNA fragmentation and reactive oxygen species (ROS) production. However, pretreatment with LJF reduced oxidative conditions, including inhibition of cell death, DNA fragmentation and ROS production. In addition, we found out chlorogenic acid as major component of LJF. Conclusions : These results could suggest that LJF contained anti-oxidative contents and exhibited protective effects against UVB on human HaCaT keratinocytes. And the effective compound of LJF which could show protective activities against UVB is chlorogenic acid. Thus, LJF and chlorogenic acid would be useful for the development of drug or cosmetics treating skin troubles.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.3
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• pp.350-356
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• 2011

Styela plicata of large (9.82~11.66 g) and small (0.93~2.21 g) sizes harvested at different times was extracted with 4 different solvents (methanol, ethanol, acetone, and water). DPPH radical scavenging and reducing power was the highest in acetone extracts of small ones (38.98% and 1.724, respectively) harvested in November. The lowest radical scavenging activity was found in water extracts of large ones (12.03% and 0.114) in December. On the other hand, large ones harvested in September showed significantly higher inhibition rate of DNA damage (water, 56.54%; methanol, 55.83%; ethanol, 48.63%) than others. Overall, the water extraction of S. plicata tended to show a higher antigenotoxic effect. In addition, water extracts of large S. plicata from November showed the highest angiotensin converting enzyme (ACE) inhibitory activity (64.38%), while that of small ones from December exhibited the lowest (51.33%). Overall the results indicate that antioxidant and antihypertensive activities S. plicata are variable depending on harvesting time, size, and extraction solvent.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.2
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• pp.149-155
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• 2011

The objective of this study was to evaluate the antioxidant and antigenotoxic activities of sansuyu fruit (Corni fructus, CF) at temperatures of $25^{\circ}C$, $50^{\circ}C$, and $90^{\circ}C$ using a water extraction method. Total phenolic content (TPC), DPPH radical-scavenging activity (RSA), and superoxide dismutase (SOD)-like activity, and ORAC (Oxygen radical absorbance capacity) values were determined. Also the antigenotoxicity of CF was determined by measuring inhibitory effects of $H_2O_2$ induced DNA damage in human leukocytes using the comet assay. The TPC in the CF extracts was 4.2, 4.6, and 5.5 g/100 g GAE in $25^{\circ}C$, $50^{\circ}C$, and $90^{\circ}C$, respectively. The DPPH RSA of the CF extracts increased in a dose-dependent manner over the range of $50\sim1000\;{\mu}g$/mL in all temperatures and the $SC_{50}$ of DPPH RSA of the CF extracts were not significantly different at different extraction temperatures. The $SC_{50}$ of SOD-like was the highest in CF extracted at $25^{\circ}C$ (1.1 mg/mL) followed by $90^{\circ}C$ (1.2 mg/mL) and $50^{\circ}C$ (1.3 mg/mL). The ORAC values of the CF extracts were not significantly different in low concentration ($10\;{\mu}M$/mL) and was in order of $25^{\circ}C$ ($5.7\;{\mu}M$ TE)< $90^{\circ}C$ ($6.2\;{\mu}M$ TE)< $50^{\circ}C$ ($8.5\;{\mu}M$ TE) in high concentration ($50\;{\mu}M$/mL). $200\;{\mu}M$ $H_2O_2$ induced DNA damages in human leukocytes were significantly reduced by the pretreatment with the CF extracts. These results suggest that sansuyu fruit (Corni fructus) can be used as a natural source for antioxidant activities and as antigenotoxic agents regardless of the water extraction temperature.

• Applied Microscopy
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• v.28 no.2
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• pp.225-236
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• 1998

Adriamycin is a one of anthracyclin antibiotics isolated from the culture media of Streptomyces peucetius var casius. The formation of reactive oxygen metabolite by redox cycling during the metabolism and the inhibition of DNA synthesis results in antineoplastic effects of adriamycin. The authors have demonstrated the effects of SOD(superoxide dismutase) or DMTU (dimethyl thiourea), which are used as an antioxidant, on the ultrastructural changes of the gastric chief cells after the administration of adriamycin in the rat. Adriamycin (30 mg/kg) was administered intraperitoneally to the Sprague-Dawley rats weighing about 220 gm and SOD (15000 unit/kg) or DMTU (500 mg/kg) were administered intraperitoneally to the rats 30 minutes after the administration of adriamycin. The gastric chief cells 24, 48 and 72 hours after the administration of adriamycin were observed with Hitachi-600 electron microscope. The results were as follows. 1. SOD or DMTU alone did not affect the ultra structures of the gastric chief cells in the rat. 2. Dilation, sacculation and segmentation of the cisternae of rough endoplasmic reticulum, dilation of the saccules of Golgi complex and dilated mitochondria with electron lucent matrix were seen in the adriamycin treated rats. In the course of time, the ultrastructures of the chief cell changed markedly. 72 hours after drug administration, severely dilated cisternae of rough endoplasmic reticulum, with clumping of chromatin around the nuclear envelope and mitochondria with electron lucent matrix and dilated cristae were seen in the chief cell. 3. The treatment of SOD is more effective than DMTU to attenuated the ultrastructural changes of the chief cells in the adriamycin administered rat. Consequently it is suggested that adriamycin would induce the degenerative changes of the organelles of the chief cell. The treatment of SOD is more effective than DMTU to attenuate the adriamycin induced damage.

• Biomolecules & Therapeutics
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• v.23 no.6
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• pp.557-563
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• 2015

Skin aging is the most readily observable process involved in human aging. Ultraviolet B (UVB) radiation causes photo-oxidation via generation of reactive oxygen species (ROS), thereby damaging the nucleus and cytoplasm of skin cells and ultimately leading to cell death. Recent studies have shown that high levels of solar UVB irradiation induce the synthesis of matrix metalloproteinases (MMPs) in skin fibroblasts, causing photo-aging and tumor progression. The MMP family is involved in the breakdown of extracellular matrix in normal physiological processes such as embryonic development, reproduction, and tissue remodeling, as well as in disease processes such as arthritis and metastasis. We investigated the effect of diphlorethohydroxycarmalol (DPHC) against damage induced by UVB radiation in human skin keratinocytes. In UVB-irradiated cells, DPHC significantly reduced expression of MMP mRNA and protein, as well as activation of MMPs. Furthermore, DPHC reduced phosphorylation of ERK and JNK, which act upstream of c-Fos and c-Jun, respectively; consequently, DPHC inhibited the expression of c-Fos and c-Jun, which are key components of activator protein-1 (AP-1, up-regulator of MMPs). Additionally, DPHC abolished the DNA-binding activity of AP-1, and thereby prevented AP-1-mediated transcriptional activation. These data demonstrate that by inactivating ERK and JNK, DPHC inhibits induction of MMPs triggered by UVB radiation.

• Journal of Photoscience
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• v.2 no.1
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• pp.37-45
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• 1995

INTRODUCTION : Psoralens are planar tricyclic furocoumarins present in numerous plants and fungi found throughout the world.' Naturally occurring and synthesized psoralen derivatives(see Figure 1) are photosensitizers of UVA especially from 320 nm to 400 nm, a range at which cellular nucleic acids and proteins are weakly absorbing if any at all. Because of their skinphotosensitizing properties, these compounds have been used in the photochemotherapy of psoriasis and vitiligo. However, undesirable side effects such as carcinoma development in hairless mice as well as possible liver damage from the use of 8-methoxypsoralen(8-MOP) have been reported. The other photobiological effects include inactivation of DNA viruses, killing and mutagenesis of bacteria, inhibition of tumor transmitting capacity of various cells, and hyperpigmentation on human and guinea pig skin. PUVA(psoralen+UVA) photochemotherapy is in fact thousands of years old, having been used in Egypt and India since B.C. 1200-2000. Photochemotherapy for a common disfiguring disease, vitiligo, was practiced in the ancient world by physicians and herbalists who used boiled extracts of the fruits of certain umbelliferous plants, e.g. Ammi majus Linnaeus in Egypt or the leguminous plants, Psoralea corylifolia L. in India. It was first described by Kuske in 19388 that photosensitization of skin by plants was related to the presence of psoralen. He identified natural psoralens in plants as photosensitizers and isolated bergapten(5methoxypsoralen) from the oil of bergamot. The scientific interest in photosensitizing psoralens, however, has grown considerably after the introduction into clinics of the psoralen photochemotherapy for the treatment of psoriasis and of other skin (abbreviation)