• Journal of Life Science
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• v.19 no.4
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• pp.502-507
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• 2009

In modern oriental medicine, bee venom therapy is being used for aqua-acupuncture to relieve pain and to cure inflammatory diseases such as rheumatoid arthritis, osteoarthritis, and gout. Bee venom therapy has been processed and reported in many experimental studies, with regard to its effects on pain alleviation, anti-inflammation, removal of fever, anti-convulsion, suppression of tumor and immunity strengthening, etc., however, its mechanism of action, molecular targeting on prostaglandin $E_2$ ($PGE_2$) production and telomere length regulation in human cancer remains unclear. In this study, we investigated the effect of bee venom on the levels of cyclooxygenases (COXs) and telomere regulatory components of A549 human lung cancer cells. Bee venom-induced anti-proliferative effects of A549 cells were associated with the inhibition of human telomerase reverse transcriptase (hTERT) as well as human telomerase RNA (hTR), transcription factor c-myc and the activity of telomerase. In addition, bee venom treatment markedly decreased the levels of COX-2 mRNA and protein expression without significant changes in the expression of COX-1, which was correlated with a decrease in $PGE_2$ synthesis. Taken together, these findings provide important new insights into the possible molecular mechanisms of the anti-cancer activity of bee venom.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.2
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• pp.91-99
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• 2009

Noninvasive imaging of molecular and biological processes in living subjects with positron emission tomography(PET) provides exciting opportunities to monitor metabolism and detect diseases in humans. Measuring these processes with PET requires the preparation of specific molecular imaging probes labeled with $^{18}F$-fluorine. In this review we describe recent methods and novel trends for the introduction of $^{18}F$-fluorine into molecules which in turn are intended to serve as imaging agents for PET study. Nucleophilic $^{18}F$-fluorination of some halo- and mesyloxyalkanes to the corresponding $^{18}F$-fluoroalkanes with $^{18}F$-fluoride obtained from an $^{18}O(p,n)^{18}F$ reaction, using novel reaction media system such as an ionic liquidor tert-alcohol, has been studied as a new method for $^{18}F$-fluorine labeling. Ionic liquid method is rapid and particularly convenient because $^{18}F$-fluoride in $H_2O$ can be added directly to the reaction media, obviating the careful drying that is typically required for currently used radiofluorination methods. The nonpolar protic tert-alcohol enhances the nucleophilicity of the fluoride ion dramatically in the absence of any kind of catalyst, greatly increasing the rate of the nucleophilic fluorination and reducing formation of byproducts compared with conventional methods using dipolar aprotic solvents. The great efficacy of this method is a particular advantage in labeling radiopharmaceuticals with $^{18}F$-fluorine for PETimaging, and it is illustrated by the synthesis of $^{18}F$-fluoride radiolabeled molecular imaging probes, such as $^{18}F$-FDG, $^{18}F$-FLT, $^{18}F$-FP-CIT, and $^{18}F$-FMISO, in high yield and purity and in shorter times compared to conventional syntheses.

• Food Science and Preservation
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• v.24 no.1
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• pp.107-115
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• 2017

The aim of this study was to investigate the hepatoprotecive effect of silk protein hydrolysates (SDH), which was prepared by acid hydrolysis, in rats. SDH itself did not exhibit any cytotoxic effect on hepatic tissues. SDH showed a protective effect on tert-butyl hydroperoxide (t-BHP)-induced hepatotoxicity and liver damage. SDH effectively reduced AST (aspartate aminotransferase) and ALT (alanine aminotransferase), which are biomarkers for liver damage, in a dose-dependent manner. Malondialdehyde (MDA), a lipid peroxidation product, was significantly reduced by SDH. A high dose of SDH (2 g/kg) reduced t-BHP-induced MDA production by 40%. Glutathione (GSH), which is an endogenous antioxidant molecule, was effectively increased by SDH treatment. GSH content was enhanced by around 2.5-fold, compared with t-BHP control, upon SDH (2 g/kg) treatment. Lactate dehydrogenase (LDH), which is an enzyme released by cell cytotoxicity, was greatly increased by t-BHP, but significantly decreased by SDH treatment. Furthermore, hematoxylin and eosin (H&E) staining showed that SDH suppressed t-BHP-induced lesions in liver tissue. Taken together, SDH might be used as a protective agent against liver damage.

• Nutrition Research and Practice
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• v.8 no.3
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• pp.272-277
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• 2014

BACKGROUND/OBJECTIVES: This study investigated the antioxidant activities and hepatoprotective effects of Schisandra chinensis Baillon extract (SCE) against tert-butyl hydroperoxide (t-BHP)-induced oxidative hepatic damage in rats. MATERIALS/METHODS: Sprague-Dawley (SD) rats were pretreated with SCE (300, 600, and 1,200 mg/kg BW) or saline once daily for 14 consecutive days. On day 14, each animal, except those belonging to the normal control group, were injected with t-BHP (0.8 mmol/kg BW/i.p.), and all of the rats were sacrificed 16 h after t-BHP injection. RESULTS: Although no significant differences in AST and ALT levels were observed among the TC and SCE groups, the high-dose SCE group showed a decreasing tendency compared to the TC group. However, erythrocyte SOD activity showed a significant increase in the low-dose SCE group compared with the TC group. On the other hand, no significant differences in hepatic total glutathione (GSH) level, glutathione reductase (GR), and glutathione peroxidase (GSH-Px) activities were observed among the TC and SCE groups. Hepatic histopathological evaluation revealed that pretreatment with SCE resulted in reduced t-BHP-induced incidence of lesions, such as neutrophil infiltration, swelling of liver cells, and necrosis. In particular, treatment with a high dose of SCE resulted in induction of phase II antioxidant/detoxifying enzyme expression, such as glutathione S-transferase (GST) and glutamate-cysteine ligase catalytic subunit (GCLC). CONCLUSIONS: Based on these results, we conclude that SCE exerts protective effects against t-BHP induced oxidative hepatic damage through the reduction of neutrophil infiltration, swelling of liver cells, and necrosis. In addition, SCE regulates the gene expression of phase II antioxidant/detoxifying enzymes independent of hepatic antioxidant enzyme activity.

• Toxicological Research
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• v.23 no.3
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• pp.263-269
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• 2007

Although taurine (2-aminoethanesulfonic acid) can inhibit oxidative stress in both animal and epidemiological studies, it is obscure whether taurine directly scavenges oxy-radicals or indirectly regulates oxidant production and/or antioxidant defense system. The reason for this discrepancy remains unknown but may be due, in part, to the lack of a validated assay system for evaluating oxy-radical scavenging capacity. The antioxidant activities of taurine and hypotaurine (2-aminoethanesulfinic acid), a precursor of taurine, against peroxyl radicals, hydroxyl radicals and peroxynitrites were determined by the total oxy-radical scavenging capacity (TOSC) assay and cell-based assay using H4IIE cells. tert-Butylhydroperoxide or hydrogen peroxide-induced cell toxicity determined by MTT assay was markedly inhibited by 10mM taurine or hypotaurine. The tert-butylhydroperoxide- or hydrogen peroxide-induced changes in oxidative stress markers, such as cellular glutathione and malondialdehyde, were ameliorated by 10mM taurine or hypotaurine. However, specific TOSC values calculated from the slope of the linear regression for taurine against peroxyl radicals, hydroxyl radicals or peroxynitrites were all less than 1 TOSC/mM. On the other hand specific TOSC values for hypotaurine against peroxyl radicals, hydroxyl radicals or peroxynitrites were 48, 2096, or 69 TOSC/mM, respectively. These results suggest that taurine protects cells against oxidative insults, which is not ascribed to directly scavenging activity of taurine against oxy-radicals. These results support the idea that the oxidation state of sulfur in antioxidants may be a determinant of oxy-radical scavenging capacity.

• Journal of the Korean Chemical Society
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• v.55 no.2
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• pp.169-176
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• 2011

The electrochemical investigation of N,N-bis (2,5-di-tert-butylphenyl)-3,4,9,10 perylenebis (dicarboximide) laser dye have been carried out using cyclic voltammetry and convolution - deconvolution voltammetry combined with digital simulation technique at a platinum electrode in 0.1 mol/L tetrabutyl ammonium perchlorate (TBAP) in solvent 1,2 dichloroethane ($CH_2Cl-CH_2Cl$). The investigated dye was reduced via consumption of two sequential electrons to form radical anion and dianion (EE mechanism). In switching the potential to positive scan, the compound was oxidized by loss of two electrons, which were followed by a fast aggregation process ($EC_1EC_2$ mechanism). The electrode reaction pathway and the chemical and electrochemical parameters of the investigated compound were determined using cyclic voltammetry and convolutive voltammetry. The extracted electrochemical parameters were verified and confirmed via digital simulation method.

• Journal of Sasang Constitutional Medicine
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• v.13 no.1
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• pp.51-60
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• 2001

Effects of Taeumjowetang on Lipid Peroxidation by Free Radicals and Oxidative Damage of Hepatocytes by tert-Butyl Hydroperoxide. 1. Purpose The present study was carried out to evaluate the antioxidant effects of Taeumjowetang in vitro. 2. Methods In this study, antioxidant effects of TJT on lipid peroxidation were determined according to the method of TBA. (Abbreviation) TJT : Taeumjowetang, TBA : 2-thiobarbituric acid. 3. Results : 1) TJT inhibited markedly peroxidation of linoleic acid during the autoxidation. 2) TJT inhibited lipid peroxidation induced by hydroxyl radical derived from H2O2-Fe2+ in rat liver homogenate. 3) TJT showed 66% scavenging effect on DPPH radical. 4) TJT exhibited a 25% inhibitory effect on superoxide generation from xanthine-xan thine oxidase system. 5) To investigate the antioxidative effects of TJT on the hepatocytes, cultured normal rat liver cells(Ac2F) were prepared and incubated with or without TJT. After 16~18hr, cells placed in DMEM medium without serum, and then incubated with 1mM t-BHP for 2hr. Viable cells were detected by MTT assay. In this test, TJT protected the cell death induced by t-BHP and significantly increased cell viability in the normal rat liver cell. (Abbreviation) DPPH : ${\alpha},{\alpha}$-diphenyl-${\beta}$-picryl hydrazyl, DMEM : Dulbecco's Modified Eagle Medium, t-BHP : terr-butyl hydroperoxide, 4. Conclusion These results suggested that TJT might play a protective role in lipid peroxidation by free radicals.

• Fisheries and Aquatic Sciences
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• v.2 no.1
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• pp.1-7
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• 1999

Antioxidant activity of a methanol extract of Symphyocladia latiuscula was evaluated by the thiocyanate method in the linoleic acid system. The methanol extract inhibited the peroxidation of linoleic acid in a dose-dependent manner. The MeOH extract was then sequentially partitioned with n-hexane, $CH_2Cl_2$, EtOAc, n-BuOH and H20. The antioxidant activity of the fractions increased in order of $CH_2Cl_2$, n-hexane, EtOAc, and n-BuOH. There was no activity found in $H_2O$ partitoned fraction by the thiocyanate method. Especially, the activities of the fractions of n-hexane and $CH_2Cl_2$ were comparable to that of 2,6-di-tert­butylhydroxytoluene (BHT). Column chromatography of the $CH_2Cl_2$ fraction over silica gel yielded cholesterol (1) and 2,3,6-tribromo 4,5-dihydroxybenzyl methyl ether (2) which were identified by instrumental analysis of MS and $^1H-$ and $^{13}C-NMR$. The latter (2) demonstrated significant antioxidant activity.

• Bulletin of the Korean Chemical Society
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• v.20 no.12
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• pp.1428-1432
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• 1999

[Fe$^{II}$(BLPA)DBCH]BPh₄ (1), a new functional model for the extradiol-cleaving catechol dioxygenases, has been synthesized, where BLPA is bis(6-methyl-2-pyridylmethyl)(2-pyridylmethyl)amine and DBCH is 3,5-di-tert-butylcatecholate monoanion. ¹H NMR and EPR studies confirm that 1 has a high-spin Fe(II) (S = 2) center. The electronic spectrum of 1 exhibits one absorption band at 386 nm, showing the yellow color of the typical [Fe$^{II}$(BLPA)] complex. Upon exposure to O₂, 1 is converted to an intense blue species within a minute. This blue species exhibits two intense bands at 586 and 960 nm and EPR signals at g = 5.5 and 8.0 corresponding to the high-spin Fe(III) complex (S = 5/2, E/D = 0.11). This blue complex further reacts with O₂ to be converted to (μ-oxo)Fe$^{III}_2$ complex within a few hours. Interestingly, 1 affords intradiol cleavage (65%) and extradiol cleavage (20%) products after the oxygenation. It can be suggested that 1 undergoes two different oxygenation pathways. The one takes the substrate activation mechanism proposed for the intradiol cleavage products after the oxidation of the $Fe^II\;to\;Fe^{III}$. The other involves the direct attack of O₂ to $Fe^{II}$ center, forming the $Fe^{III}$-superoxo intermediate which can give rise to the extradiol cleavage products. 1 is the first functional Fe(II) complex for extradiol-cleaving dioxygenases giving extradiol cleavage products.

• Korean Journal of Weed Science
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• v.14 no.1
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• pp.28-33
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• 1994

This study was conducted to investigate the efficacy of weed control by pyributicarb{O-[3-tert-butylphenyl] N-[6-methoxy-2-pyridyl]-N-methyl thiocarbamate}/bensulfuron-methyl{methyl 2-[[[[[[4, 6-dimethoxypyrimidin-2-yl] amino] carbonyl] amino] sulfonyl] methyl] benzoate} SC and oxadiazon{5-tert-butyl-3-[2,4-dichloro-5-isopropoxyphenyl]-1,3,4-oxadiazol-2(3)-one}/bensulfuron-methyl SC, and to develope weed control methods for paddy rice. There was little difference between suspension concentrate and granule of pyributicarb/bensulfuron-methyl and oxadiazon/bensulfuron-methyl combination in the effect of weed control. Pyributicarb/bensulfuron-methyl SC and oxadiazon/bensulfuron-methyl SC were diffused from the point of application to 6m. Pyributicarb/bensulfuron-methyl SC applied on water surface from irrigation inlet and in paddy water from dike controlled more than 90% of weeds. Pyributicarb/bensulfuron-methyl SC was precipitated about 1-2cm per 1 hour after dripping on water surface. The efficacy of weed control by pyributicarb/bensulfuron-methyl SC was higher in 0-1cm than in 6-7cm standing water depth.