• The Korean Journal of Physiology and Pharmacology
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• v.3 no.4
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• pp.393-404
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• 1999

We have reported that hypoxia stimulates EDRF(s) release from endothelial cells and the release may be augmented by previous hypoxia. As a mechanism, it was hypothesized that reoxygenation can stimulate EDRF(s) release from endothelial cells and we tested the hypothesis via bioassay experiment. In the bioassay experiment, rabbit aorta with endothelium was used as EDRF donor vessel and rabbit carotid artery without endothelium as a bioassay test ring. The test ring was contracted by prostaglandin $F_{2a}\;(3{\times}10^{-6}\;M)$ which was added to the solution perfusing through the aorta. Hypoxia was evoked by switching the solution aerated with 95% $O_2/5%\;CO_2$ mixed gas to one aerated with 95% $O_2/5%\;CO_2$ mixed gas. Hypoxia/reoxygenation were interexchanged at intervals of 2 minutes (intermittent hypoxia). In some experiments, endothelial cells were exposed to 10-minute hypoxia (continuous hypoxia) and then exposed to reoxygenation and intermittent hypoxia. In other experiments, the duration of reoxygenation was extended from 2 minutes to 5 minutes. When the donor aorta was exposed to intermittent hypoxia, hypoxia stimulated EDRF(s) release from endothelial cells and the hypoxia-induced EDRF(s) release was augmented by previous hypoxia/reoxygenation. When the donor aorta was exposed to continuous hypoxia, there was no increase of hypoxia-induced EDRF(s) release during hypoxia. But, after the donor aorta was exposed to reoxygenation, hypoxia-induced EDRF(s) release was markedly increased. When the donor aorta was pretreated with nitro-L-arginine $(10^{-5}$ M for 30 minutes), the initial hypoxia-induced EDRF(s) release was almost completely abolished, but the mechanism for EDRF(s) release by the reoxygenation and subsequent hypoxia still remained to be clarified. TEA also blocked incompletely hypoxia-induced and hypoxia/reoxygenation-induced EDRF(s) release. EDRF(s) release by repetitive hypoxia and reoxygenation was completely blocked by the combined treatment with nitro-L-arginine and TEA. Cytochrome P450 blocker, SKF-525A, inhibited the EDRF(s) release reversibly and endothelin antgonists, BQ 123 and BQ 788, had no effect on the release of endothelium-derived vasoactive factors. Superoxide dismutase (SOD) and catalase inhibited the EDRF(s) release from endothelial cells. From these data, it could be concluded that reoxygenation stimulates EDRF(s) release and hypoxia/reoxygenation can release not only NO but also another EDRF from endothelial cells by the production of oxygen free radicals.

• Nutrition Research and Practice
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• v.3 no.2
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• pp.156-161
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• 2009

Hyperglycemia in the diabetic state increases oxidative stress and antioxidant therapy can be strongly correlated with decreased risks for diabetic complications. The purpose of this study is to determine antioxidant effect of garlic and aged black garlic in animal model of type 2 diabetes. The antioxidant activity of garlic and aged black garlic was measured as the activity in scavenging free radicals by the trolox equivalent antioxidant capacity (TEAC) assay. Three week-old db/db mice were fed AIN-93G diet or diet containing 5% freeze-dried garlic or aged black garlic for 7 weeks after 1 week of adaptation. Hepatic levels of lipid peroxides and activities of antioxidant enzymes were measured. TEAC values of garlic and aged black garlic were $13.3{\pm}0.5$ and $59.2{\pm}0.8{\mu}mol/g$ wet weight, respectively. Consumption of aged black garlic significantly decreased hepatic thiobarbituric acid reactive substances (TBARS) level compared with the garlic group which showed lower TBARS level than control group (p<0.05). Activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) of garlic and aged black garlic group were significantly elevated compared to the control group. Catalase (CAT) activity of aged black garlic group was increased compared with the control group. These results show that aged black garlic exerts stronger antioxidant activity than garlic in vitro and in vivo, suggesting garlic and aged black garlic, to a greater extent, could be useful in preventing diabetic complications.

• Microbiology and Biotechnology Letters
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• v.34 no.2
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• pp.158-165
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• 2006

In this study, we investigated the biological activity of antioxidant and antibacterial activity of citrus by-product ferment. Among the six probiotic bacteria, Bacillus subtilis and Saccharomyces cerevisiae had the highest antioxidant activity. Hot water extracts from citrus by-product of ferment were screened for antibacterial activity fish pathogenic bacteria by paper disc method. Among the various hot water extracts, the Bacillus subtilis, Saccharomyces cerevisiae, Pediococcus pentosaceus, Lactobacillus rhamnosus, Lactobacillus plantarum, Enterococcus faecium showed relatively strong antibacterial activities in the order. The reducing activity on the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and $O^{2-}$ and OH radical scavenging potential were sequentially screened, in search for antioxidant activities of citrus by-product ferment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.7
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• pp.1053-1062
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• 2011

Reactive oxygen species (ROS), including singlet oxygen (${O_2}^1$), superoxide anion radical ($O_2{\cdot}^-$), hydroxyl radical ($HO{\cdot}$), peroxyl radical ($ROO{\cdot}$), hydrogen peroxide ($H_2O_2$), and hypochlorous (HOCl), are generated as byproducts of normal cellular metabolism. ROS induce damage to many biological molecules, such as lipids, proteins, carbohydrates, and DNA. It is widely believed that some degenerative diseases caused by ROS can be prevented by the high intake of fruits and vegetables due to their antioxidant activities. Recently, research on natural antioxidants has become increasingly active in various fields. Several assays have been developed to measure the total antioxidant capacity of antioxidants in fruits and vegetables in vitro. These assays include those for DPPH radical scavenging activity, SOD-like activity, total polyphenol content, oxygen radical absorbance capacity, reducing power, trolox equivalent antioxidant capacity (ABTS assay), single-cell gel electrophoresis (comet assay), and a cellular antioxidant activity assay. Because different antioxidant compounds may act through different mechanisms in vitro, no single assay can fully evaluate the total antioxidant capacity of foods. Due to the complexity of the composition of foods, it is important to be able to measure antioxidant activity using biologically relevant assays. In this review, recently used assays were selected for extended discussion, including a comparison of the advantages and disadvantages of each assay and their application to fruits and vegetables.

• KSBB Journal
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• v.26 no.1
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• pp.27-32
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• 2011

For the development of functional food and cosmetics using hot water extract of Muraenesox cinereus's skin, contents of vitamin, amino acid and element, and antioxidant activity were investigated. The results are shown as follows: among vitamins, A(0.21mg/100 g), C (78.12mg/100 g), $D_3$ (0.03 mg/100 g), E (1.97 mg/100 g) and Niacin (2.53mg/100 g) were detected, respectively.Mineral contents were an order of K > P > Na > Mg > Ca > Fe and Zn. Contents of total amino acids were an order of Pro > Gly > Arg > Glu > Phe > Ala. Especially, the sum of total amino acids was 27.17 mg/100 mL, which was about 4.0 fold higher than that of free amino acid. DPPH radical scavenging activity of hot water extract of M. cinereus's skin at 25 mg/mL was 63.5% and did not increase at above 50 mg/mL. Activities of antioxidant enzymes in the liver of ethanol-treated rats using hot water extract of M. cinereus's skin were investigated. Compared to control group, activities of ADH and GSH-px were decreased. In the case of CAT and SOD activity, they were increased. These results showed that the hot water extract of M. cinereus's skin can be applied to raw macterial for functional food and cosmetics.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.4
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• pp.411-418
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• 2007

Oxidative stress can play a key role in cadmium (Cd)-induced dysfunction. The present study examined the effect of pine needle water extract (PN) on Cd-induced oxidative stress in rats. Sprague-Dawley male rats were divided into three groups: normal group, Cd control group (Cd) and PN-administered Cd group (Cd-PN). $CdCl_2$ in 0.9% NaCl was administered orally with a dose of 5mg/kg of body weight/week, while the PN was administered orally with a dose of 1.26g/kg of body weight/day. Body weight gain was not different between groups, whereas food intakes were significantly lower in the Cd-PN group than in normal or Cd group. Relative liver weight was significantly increased by cadmium administration compared to the normal group. Hepatic cytochrome P450 was significantly lower in Cd and Cd-PN groups than in normal group, while xanthine oxidase and alcohol dehydrogenase activities were significantly higher in the Cd-PN group than in normal or Cd group. Increased hepatic superoxide dismutase, monoamine oxidase, catalase, and glutathione peroxidase activities by cadmium administration were significantly decreased by PN supplement. PN did not affect the hepatic glutathione content in cadmium-administered rats; however, PN significantly lowered the hepatic lipid peroxide level and plasma alanine transferase activity compared to the Cd control group. These results suggest that the PN may alleviate Cd-induced oxidative stress without hepatotoxicity.

• YAKHAK HOEJI
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• v.56 no.3
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• pp.191-197
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• 2012

We previously reported that the novel isoflavone-free peptide mixture (black soybean peptide, BSP) had several beneficial effects like antiobesity and hypotriglyceridemic effect. However, there are no reports for BSP on anti-hypertensive activity. BSP induced heme oxygenase-1 (HO-1) in HUVECs, thus investigated the HO-1-induced activity in HUVECs and the anti-hypertensive effects in SHR animal model. BSP significantly induced HO-1 expression both at transcriptional and protein levels in a time- and dose-dependent manner as measured by RT-PCR and Western blot analysis, respectively. These inductions were abolished by pretreatment of N-acetyl-cystein (NAC, 1~10 mM), but not by employing Tempol, a superoxide dismutase (SOD) mimetic (1~5 mM). As expected, enzymatic activity (~2 fold) determined by bilirubin formation assay and cGMP concentration (~6 fold) were significantly increased in BSP-treated cells. Based on the numerous evidences on the beneficial effects of HO-1 and our results, we investigated in vivo effects of BSP on the antihypertensive activity. The administration of BSP (1% in drinking water) significantly decreased mean blood pressure (BP) (from $218.6{\pm}6.99$ to $190.0{\pm}3.42$ mm Hg, p<0.01). This result indicates that BSP is strong inducer of HO-1 expression, which may be triggered by oxidative stress, and has anti-hypertensive activity.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.140-140
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• 2017

Nutritious and functional foods from crop have received great attention in recent years. Colored-grain wheat contains high phenolic compound and a large number of flavonoid. The anthocyanin and polyphenolic synthesis and accumulation is generally stimulated in response to biotic or abiotic stresses. Here, we analyzed genome wide transcripts in seedling of colored-grain wheat response to ABA and PEG treatment. About 900 and 1500 transcripts (p-value < 0.05) from ABA and PEG treatment were aligned to IWGSC1+popseq DB which is composed of over 110,000 transcripts including 100,934 coding genes. NR protein sequences of Poaceae from NCBI and protein sequence of transcription factors originated from 83 species in plant transcription factor database v3.0 were used for annotation of putative transcripts. Gene ontology analysis were conducted and KEGG mapping was performed to show expression pattern of biosynthesis genes related in flavonoid, isoflavonoid, flavons and anthocyanin biopathway. DroughtDB (http://pgsb.helmholtz-muenchen.de/droughtdb/) was used for detection of DEGs to explain that physiological and molecular drought avoidance by drought tolerance mechanisms. Drought response pathway, such as ABA signaling, water and ion channels, detoxification signaling, enzymes of osmolyte biosynthesis, phospholipid metabolism, signal transduction, and transcription factors related DEGs were selected to explain response mechanism under water deficit condition. Anthocyanin, phenol compound, and DPPH radical scavenging activity were measured and antioxidant activity enzyme assays were conducted to show biochemical adaptation under water deficit condition. Several MYB and bHLH transcription factors were up-regulated in both ABA and PEG treated condition, which means highly expressed MYB and bHLH transcription factors enhanced the expression of genes related in the biosynthesis pathways of flavonoids, such as anthocyanin and dihydroflavonols in colored wheat seedlings. Subsequently, the accumulation of total anthocyanin and phenol contents were observed in colored wheat seedlings, and antioxidant capacity was promoted by upregulation of genes involved in maintaining redox state and activation of antioxidant scavengers, such as CAT, APX, POD, and SOD in colored wheat seedlings under water deficit condition. This work may provide valuable and basic information for further investigation of the molecular responses of colored-grain wheat to water deficit stress and for further gene-based studies.

• The Korea Journal of Herbology
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• v.35 no.6
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• pp.21-28
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• 2020

Objectives : The objective of this study was to investigate the improvement effect of Sprout of Coix lacryma-jobi var. mayuen Stapf water extract (SC) on the dextran sulfate sodium (DSS)-induced ulcerative colitis mice. Methods : The antioxidant activity of SC was measured through total polyphenol and total flavonoid content in vitro. The experiment was conducted with seven-week-old male Balb/c mice. After 1 week adaptation, acute colitis was induced by oral administration of 5% DSS dissolved in drinking water, for 7 days. And normal mice received drinking water without DSS throughout the entire experimental period. For each experiment, the mice were divided into 4 groups and 24 colitis mice were arbitrarily allocated into 3 groups (n = 8/group); Normal group, Control group, SC 100 mg/kg treated group (SCL), SC 200 mg/kg treated group (SCH). Serum and colon tissues were collected after one weeks of drug administration. Results : ROS levels, ONOO^- levels, AST, and ALT in serum were decreased in SC treated groups compared to the control group. Western blotting measurements of Nrf2, HO-1, SOD, catalase, GPx-1/2, IL-4, IL-10, and Bcl2 showed that the SC treated groups was increased compared to the Control group. Also, western blot measurements of NF-κBp65, p-IκBα, COX-2, iNOS, TNF-α, IL-1β, Bax, and Caspase-3 showed that the SC treated groups was reduced compared to the Control group. Conclusion : Taken together, these results suggest that SC treatment can attenuate the DSS-induced colitis though inhibiting NF-κB pathway and enhancing Nrf2 pathway. Therefore, SC was the potential to be used as a natural therapeutic drug.

• Journal of Nutrition and Health
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• v.36 no.2
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• pp.117-124
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• 2003

This study was designed to test the effect of Korean traditional tea materials on oxygen-free radical metabolism in lead (Pb) -administered rats. Male rats were divided into normal, Pb-control (Pb-Con) and Pb-water extract of green tea (Camellia sinensis; GT) , persimmon leaf (Diospyros kaki; PL) , safflower seed (Carhamus tinctorius: SS) , Du-Zhong (Eucommia ulmoides; EU) groups, respectively. Pb intoxication was induced by administration of lead acetate (25 mg/kg. B.W., oral) weekly. The extract was administered based on 1.26 g of raw material/kg B.W./day for 4 weeks. When the GT, PL, SS and EU were supplemented to the Pb-administered rats, hepatic lipid peroxide levels were significantly lower compared to the Pb-Con group. Hepatic cytochrom P-450 content and aminopyrine N-demethylase activity was lower in the Pb-Con group than in the normal group, whereas xanthine oxidase activity was significantly elevated in Pb-administered rats. The water extract of GT, PL, SS and EU supplementation attenuated changes in enzyme activities generating reactive oxygen species in the liver. Hepatic superoxide dismutase, catalase and glucose 6-phosphate dehydrogenase activities were significantly higher in the Pb-Con group than in the normal group, while monoamine oxidase activity also tended to increase in the Pb-administered rats. However, glutathione peroxidase and glutathione S-transferase activities, and glutathione content significantly decreased through Pb intoxication. The supplementation of GT, PL, SS and EU induced alleviation changes of hepatic antioxidant enzyme activity.