• 한방재활의학과학회지
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• 제20권2호
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• pp.51-61
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• 2010

Objectives : The purpose of this study was to investigate antioxidant effects of curcumin from Curcumae Longae Radix. Methods : Using HepG2 Iiver-like cells, the antioxidant effects of curcumin, one of main components from Curcumae Longae Radix, and its analogues have been evaluated by measuring their effects on cytotoxicity induced by $H_2O_2$. Results : The pre-incubation for 6 hours with curcumin, bis-demethoxycurcumin, or dimethoxycurcumin protected HepG2 cells from $H_2O_2$-induced toxicity in a dose-dependent manner. However, tetrahydrocurcumin, one of curcumin metabolites, did not protect HepG2 cells from $H_2O_2$-induced toxicity. Interestingly, curcumin, bis-demethoxycurcumin, and dimethoxycurcumin were increased in the protein levels of heme oxygenase-1(HO-1) at concentrations that were also effective in cellular protection. In contrast, tetrahydrocurcumin did not induce HO-1 expression. Tin protoporphyrin-IX, an inhibitor of HO-1 activity, significantly abolished cytoprotection afforded by curcumin, bis-demethoxycurcumin and dimethoxycurcumin. Conclusions : These results demonstrate that curcumin, bis-demethoxycurcumin, and dimethoxycurcumin with two conjugated doble bonds on their structures may reduce $H_2O_2$-induced oxidative stress through HO-1 expression. HO-1 induction may be one of antioxidant pathways by which curcumin protects from oxidative stress-induced cytotoxicity.

• IMMUNE NETWORK
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• 제11권6호
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• pp.376-382
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• 2011

Background: Carbon monoxide (CO) is a cytoprotective and homeostatic molecule with important signaling capabilities in physiological and pathophysiological situations. CO protects cells/tissues from damage by free radicals or oxidative stress. NAD(P)H:quinone oxidoreductase (NQO1) is a highly inducible enzyme that is regulated by the Kelch-like ECH-associated protein 1 (Keap1)/nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) pathway, which is central to efficient detoxification of reactive metabolites and reactive oxygen species (ROS). Methods: We generated NQO1 promoter construct. HepG2 cells were treated with CO Releasing Molecules-2 (CORM-2) or CO gas and the gene expressions were measured by RT-PCR, immunoblot, and luciferase assays. Results: CO induced expression of NQO1 in human hepatocarcinoma cell lines by activation of Nrf2. Exposure of HepG2 cells to CO resulted in significant induction of NQO1 in dose- and time-dependent manners. Analysis of the NQO1 promoter indicated that an antioxidant responsible element (ARE)-containing region was critical for the CO-induced Nrf2-dependent increase of NQO1 gene expression in HepG2 cells. Conclusion: Our results suggest that CO-induced Nrf2 increases the expression of NQO1 which is well known to detoxify reactive metabolites and ROS.

• The Korean Journal of Physiology and Pharmacology
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• 제12권5호
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• pp.275-280
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• 2008

A brief ischemic insult induces significant protection against subsequent massive ischemic events. The molecular mechanisms known as preconditioning (PC)-induced ischemic tolerance are not completely understood. We investigated whether kinetic changes of cyclooxygenase (COX)-2 during reperfusion time-periods after PC were related to ischemic tolerance. Rats were given PC by occlusion of middle cerebral artery (MCAO) for 10 min and sacrificed after the indicated time-periods of reperfusion (1, 2, 4, 8, 12, 18 or 24 h). In PC-treated rats, focal ischemia was induced by occlusion of MCA for 24 h and brain infarct volume was then studied to determine whether different reperfusion time influenced the damage. We report that the most significant protection against focal ischemia was obtained in rats with 8 h reperfusion after PC. Administration of indomethacin (10 mg/kg, oral) or rofecoxib (5 mg/kg, oral) 48 h prior to PC counteracted the effect of PC. Immunohistochemical analysis showed that COX-2 and HO-l protein were induced in PC-treated rat brain, which was significantly inhibited by rofecoxib. Taken together, we concluded that the kinetic changes of COX-2 expression during the reperfusion period after PC might be partly responsible for ischemic tolerance.

• The Korean Journal of Physiology and Pharmacology
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• 제24권5호
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• pp.373-384
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• 2020

Paeonol, quercetin, β-sitosterol, and gallic acid extracted from Moutan Cortex had been reported to possess anti-oxidative, anti-inflammatory, and anti-tumor activities. This work aimed to illustrate the potential anti-oxidative mechanism of monomers in human liver hepatocellular carcinoma (HepG2) cells-induced by hydrogen peroxide (H₂O₂) and to evaluate whether the hepatoprotective effect of monomers was independence or synergy in mice stimulated by carbon tetrachloride (CCl₄). Monomers protected against oxidative stress in HepG2 cells in a dose-response manner by inhibiting the generation of reactive oxygen species, increasing total antioxidant capacity, catalase and superoxide dismutase (SOD) activities, and activating the antioxidative pathway of nuclear factor E2-related factor 2/Kelch-like ECH-associated protein 1 (Nrf2/Keap1) signaling pathway. We found that the in vitro antioxidant capacities of paeonol and quercetin were better than those of β-sitosterol and gallic acid. Furthermore, paeonol apparently diminished the levels of alanine transaminase and aspartate aminotransferase, augmented the contents of glutathione and SOD, promoted the expressions of Nrf2 and heme oxygenase-1 proteins in mice stimulated by CCl₄. In HepG2 cells, paeonol, quercetin, β-sitosterol, and gallic acid play a defensive role against H₂O₂-induced oxidative stress through activating Nrf2/Keap1 pathway, indicating that these monomers have anti-oxidative properties. Totally, paeonol and quercetin exerted anti-oxidative and hepatoprotective effects, which is independent rather than synergy.

• The Korean Journal of Physiology and Pharmacology
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• 제24권6호
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• pp.481-492
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• 2020

The present study aimed to examine the effect of allyl isothiocyanate (AITC) on chronic obstructive pulmonary disease and to investigate whether upregulation of multidrug resistance-associated protein 1 (MRP1) associated with the activation of the PARK7 (DJ-1)/nuclear factor erythroid 2-related factor 2 (Nrf2) axis. Lung function indexes and histopathological changes in mice were assessed by lung function detection and H&E staining. The expression levels of Nrf2, MRP1, heme oxygenase-1 (HO-1), and DJ-1 were determined by immunohistochemistry, Western blotting and reverse transcription-quantitative polymerase chain reaction. Next, the expression of DJ-1 in human bronchial epithelial (16HBE) cells was silenced by siRNA, and the effect of DJ-1 expression level on cigarette smoke extract (CSE)-stimulated protein degradation and AITC-induced protein expression was examined. The expression of DJ-1, Nrf2, HO-1, and MRP1 was significantly decreased in the wild type model group, while the expression of each protein was significantly increased after administration of AITC. Silencing the expression of DJ-1 in 16HBE cells accelerated CSE-induced protein degradation, and significantly attenuated the AITC-induced mRNA and protein expression of Nrf2 and MRP1. The present study describes a novel mechanism by which AITC induces MRP1 expression by protecting against CS/CSE-mediated DJ-1 protein degradation via activation of the DJ-1/Nrf2 axis.

• 동의생리병리학회지
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• 제20권6호
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• pp.1459-1466
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• 2006

The water extract of Hwansodan has been traditionally used for treatment of ischemic brain damage in oriental medicine. However, little is known about the mechanism by which the water extract of Hwansodan rescues cells from neurodegenerative disease. PC12 pheochromocytoma cells have been used extensively as a model for studying the cellular and molecular mechanisms of neuronal cell damages. Under deprivation of growth factor and ischemic injury, PC12 cells spontaneously undergoes apoptotic cell death. Serum and glucose deprivation markedly decreased the viability of PC12 cells, which was characterized with apparent apoptotic features such as membrane blebbing as well as fragmentation of genomic DNA and nuclei. However, the aqueous extract of Hwansodan significantly reduced serum and glucose deprivation-induced cell death and apoptotic characteristics through reduction of intracellular peroxide generation. Pretreatment of Hwansodan also ingibited the activation of caspase-3, in turn, degradation of ICAD/DFF45 was completely abolished in serum and glucose deprivated cells. Furthermore, pretreatment of Hwansodan obviously increased heme oxygenase 1 (HO-1) expression in PC12 cells. Taken together, the data suggest that the protective effects of Hwansodan against serum and glucose deprivation induced oxidative injuries may be achieved through the scavenging of reactive oxygene species accompanying with HO-1 induction.

• 대한지역사회영양학회지
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• 제3권4호
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• pp.556-564
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• 1998

The purpose of this study was to assess the iron nutritional status of college women residing in the Kyungin area. The anthropometric parameters, nutrient intake, and biochemical status of iron were measured for 102 college women. The mean height and weight were 160.3cm and 52.4kg, respectively. The proportion of subjects whose BMI was less than 20 was 41.3%. The proportion of subjects assessed as overweight(25$\geq$25%) assessed by the fat percent(FP) was 53.9%. The mean daily intake of iron was 13.90mg(77.1% of RDA), composed of 0.97mg of heme iron and 12.44mg(69.0% of RDA). When the sources of iron were grouped as rice(including bread), noodle, soup, side dish, and snack, noodle provided, 3.95mg of iron regarded as the highest amount. Subjects were taking 6.72mg(51.4% of RDA) of iron per day from main dishes(rice, bread and noodle). The fifty five percent of the subjects showed iron depletion(serum femitin<20ng/ml)and 33.4% showed suppressed erythropoiesis with iron deficiency(serum ferritin<10ng/ml). The anemic subjects assessed with transferrin saturation (<15%) represented 33.3% of the test population, whereas 11.8% of the subjects possessed less than 12g/dl of hemoglobin. Subjects not satisfied with their body shape were having significantly lower amount of energy intake(p<0.05) than the subjects satisfied with their body shape. College women having mothers who graduated from university had a significantly decreased amount of energy, carbohydrates, fat and vitamin C(p<0.05). The mean RBC and serum iron of the subjects who were on a diet more than one month were lower than those of the subjects who were not on a diet(p<0.05).

• 방사선산업학회지
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• 제2권3호
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• pp.97-104
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• 2008

Cinnamate-4-hydroxylase (C4H) is a key enzyme of phenylpropanoid pathway, which leads a variety of secondary metabolites to participate in differentiation and protection of plant against environmental stresses. In this study, we isolated a full-length cDNA of the C4H gene from a black raspberry (Rubus occidentalis L.), using a reverse transcriptase-PCR and rapid amplification of the cDNA ends (RACE)-PCR. The full-length cDNA of the RocC4H gene contained a 1,515 bp open reading frame (ORF) encoding a 504 amino acid protein with a calculated molecular weight of about 57.9 kDa and an isoelectric point (pI) value of 9.1. The genomic DNA analysis revealed that RocC4H gene had three exons and two introns. By multiple sequence alignment, RocC4H protein was highly homologous with other plant C4Hs, and the cytochrome P450-featured motifs, such as the heme-binding domain, the T-containing binding pocket motif (AAIETT), the ERR triad, and the tetrapeptide (PPGP) hinge motif, were highly conserved. Southern blot analysis revealed that RocC4H is a single copy gene in R. occidentalis.

• Archives of Pharmacal Research
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• 제18권2호
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• pp.105-112
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• 1995

In ordedr to gain insight into the mechanisms byl which erythropoietin promotes erythropoiesis, effects of various inhibitors on the erythropoietin-propmoted differentiation of erythroid progenitor cells and on the erythroid progenitor cells and on the erythropoietin-promoted $Ca^{++}$ uptake in the progenitor cells were determined, and the relationship between the inhibitory activity of each inhibitor cells were determined, and he relationship between the inhibitory activity of each inhibitor toward the differentiation and channel blocker (varapamil), a $Ca^{++}$ chelator (EDTA) and a protein kinase C inhibitor (stauroporine). All of these agents inhibited both the erythropoietin-mediated differentiation of the erythroid progenitor cells, as determined by the incroporation of $^{59}Fe$ into heme, and $Ca^{++}$ uptake in a concentrtion dependent manner. In the cases of varapamil and EDTA, the half-miximal inhibitory concentration $(IC_{50})$ values for differentiation of the progenitor cells may be theconsequence of the inhibition of the $Ca^{++}$ uptake in a concentration dependent manner. In the cases of varapamil and EDTA, the half-miximal inhibitory concentration dependent manner. In the cases of verapamil and EDTA, the half-miximal inhibitory concentration $(IC_{50})$ values for differentiation of the progenitor cells may be the consequence of the inhibition of the $Ca^{++}$ uptake by the inhibitor. On the other hand, in the cases of genistein and stauroporine, the $IC_{50}$ values for inhibition of differentitation were significantly different from that for inhibition of $Ca^{++}$uptake. These results suggest that the mechanism of inhibition of differentiation by these two inhibitors in complex. However, taken all together, the above results support the proposition that $Ca^{++}$ uptake may play a role in the erythropoietin-mediated differentiation of erythoid progenitor cells.

• Archives of Pharmacal Research
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• 제27권7호
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• pp.769-775
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• 2004

Hepatic ischemia and reperfusion (l/R) predisposes the liver to secondary stresses such as endotoxemia, possibly via dysregulation of the hepatic microcirculation secondary to an imbalanced regulation of the vascular stress genes. In this study, the effect of hepatic I/R on the hepatic vasoregulatory gene expression in response to endotoxin was determined. Rats were subjected to 90 min of hepatic ischemia and 6 h of reperfusion. Lipopolysaccharide (LPS, 1 mg/kg) was injected intraperitoneally after reperfusion. Plasma and liver samples were obtained 6 h after reperfusion for serum aminotransferase assays and RT-PCR analysis of the mRNA for the genes of interest： endothelin-1 (ET-1), its receptors $ET_A$ and $ET_B$, endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS), heme oxygenase-1 (HO-1), cyciooxygenase-2 (COX-2), and tumor necrosis factor-a (TNF-${\alpha}$). The activities of serum aminotransferases were significantly increased in the I/R group. This increase was markedly potentiated by LPS treatment. The ET-1 mRNA was increased by LPS alone, and this increase was significantly greater in both the I/R alone and I/R ＋ LPS groups compared to the sham. There were no significant differences in ETA receptor mRNA levels among any of the experimental groups. $ET_B$ mRNA was increased by both LPS alone and I/R alone, with no significant difference between the I/R alone and I/R ＋ LPS groups. The eN OS and HO-1 transcripts were increased by I/R alone and further increased by I/R ＋ LPS. The iNOS mRNA levels were increased by I/R alone, but increased significantly more by both LPS alone and I/R ＋ LPS compared to I/R alone. The TNF-${\alpha}$ mRNA levels showed no change with I/R alone, but were increased by both LPS alone and I/R ＋ LPS. The COX-2 expression was increased significantly by I/R alone and significantly more by I/R ＋ LPS. Taken collectively, significantly greater induction of the vasodilator genes over the constriction forces was observed with I/R ＋ LPS. These results may partly explain the increased susceptibility of ischemic livers to injury as a result of endotoxemia.