1.A Novel In Vitro Method for the Metabolism Studies of Radiotracers Using Mouse Liver S9 Fraction.
Eun Kyoung RYU ; Yearn Seong CHOE ; Dong Hyun KIM ; Sang Yoon LEE ; Yong CHOI ; Kyung Han LEE ; Byung Tae KIM
Korean Journal of Nuclear Medicine 2004;38(4):325-329
PURPOSE: Usefulness of mouse liver S9 fraction was evaluated for the measurement of the metabolites in the in vitro metabolism study of 18F-labeled radiotracers. MATERIALS AND METHODS: Mouse liver S9 fraction was isolated at an early step in the course of microsome preparation. The in vitro metabolism studies were carried out by incubating a mixture containing the radiotracer, S9 fraction and NADPH at 37 degrees C, and an aliquot of the mixture was analyzed at the indicated time points by radio-TLC. Metabolic defluorination was further confirmed by the incubation with calcium phosphate, a bone mimic. RESULTS: The radiotracer [18F]1 underwent metabolic defluorination within 15 min, which was consistent with the results of the in vivo method and the in vitro method using microsome. Radiotracer [18F]2 was metabolized to three metabolites including 4-[18F]fluorobenzoic acid within 60 min. It is likely that the one of these metabolites at the origin of radio-TLC was identical with the one that obtained from the in vivo and in vitro (microsome) method. Compared with the in vitro method using microsome, the method using S9 fraction gave a similar pattern of the metabolites but with a different ratio, which can be explained by the presence of cytosol in the S9 fraction. CONCLUSION: These results suggest that the findings of the in vitro metabolism studies using S9 fraction can reflect the in vivo metabolism of novel radiotracers in the liver. Moreover, this method can be used as a tool to determine metabolic defluorination along with calcium phosphate absorption method.
Absorption
;
Animals
;
Calcium
;
Cytosol
;
Liver*
;
Metabolism*
;
Mice*
;
Microsomes
;
NADP
2.Induction of NADPH oxidases and antioxidant proteins by Porphyromonas gingivalis in KB cells.
Min Jeong KIM ; Hyun Ju CHUNG ; Byung Ju PARK ; Hae Ryoung PARK ; Tae Hoon LEE
The Journal of the Korean Academy of Periodontology 2006;36(4):863-878
No abstract available.
Humans
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KB Cells*
;
NADP*
;
NADPH Oxidase
;
Oxidoreductases*
;
Porphyromonas gingivalis*
;
Porphyromonas*
3.Concomitant use of corticosteroid and antimicrobials for liver abscesses in patients with chronic granulomatous disease.
Korean Journal of Pediatrics 2016;59(4):196-201
Chronic granulomatous disease (CGD) is a rare inherited disorder caused by defective nicotinamide adenine dinucleotide phosphate oxidase enzyme and characterized by recurrent bacterial and fungal infections. Although liver abscess is a common manifestation of CGD, its management in CGD patients is not well-defined. In addition, the generalized guidelines for treating liver abscesses do not necessarily apply to CGD patients. Corticosteroids are commonly used to control granulomatous complications, such as inflammatory gastrointestinal and genitourinary lesions, in patients with CGD, Corticosteroids have also been used in combination with antimicrobials to treat refractory infections in patients with CGD. Because corticosteroids are capable of suppressing symptomatic inflammation, all potential infections must be adequately controlled prior to corticosteroid initiation. We report 3 typical CGD cases with liver abscesses refractory to conventional treatments that were successfully treated with the concomitant use of corticosteroid and antimicrobials. It remains unclear whether corticosteroid therapy is required for liver abscesses in CGD refractory to conventional treatments. However, based on our observations, use of corticosteroids in combination with optimal antimicrobials should be considered for refractory liver abscesses in CGD.
Adrenal Cortex Hormones
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Granulomatous Disease, Chronic*
;
Humans
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Inflammation
;
Liver Abscess*
;
Liver*
;
NADP
;
Oxidoreductases
4.Upregulation of mitochondrial NAD⁺ levels impairs the clonogenicity of SSEA1⁺ glioblastoma tumor-initiating cells.
Myung Jin SON ; Jae Sung RYU ; Jae Yun KIM ; Youjeong KWON ; Kyung Sook CHUNG ; Seon Ju MUN ; Yee Sook CHO
Experimental & Molecular Medicine 2017;49(6):e344-
Emerging evidence has emphasized the importance of cancer therapies targeting an abnormal metabolic state of tumor-initiating cells (TICs) in which they retain stem cell-like phenotypes and nicotinamide adenine dinucleotide (NAD⁺) metabolism. However, the functional role of NAD⁺ metabolism in regulating the characteristics of TICs is not known. In this study, we provide evidence that the mitochondrial NAD⁺ levels affect the characteristics of glioma-driven SSEA1⁺ TICs, including clonogenic growth potential. An increase in the mitochondrial NAD⁺ levels by the overexpression of the mitochondrial enzyme nicotinamide nucleotide transhydrogenase (NNT) significantly suppressed the sphere-forming ability and induced differentiation of TICs, suggesting a loss of the characteristics of TICs. In addition, increased SIRT3 activity and reduced lactate production, which are mainly observed in healthy and young cells, appeared following NNT-overexpressed TICs. Moreover, in vivo tumorigenic potential was substantially abolished by NNT overexpression. Conversely, the short interfering RNA-mediated knockdown of NNT facilitated the maintenance of TIC characteristics, as evidenced by the increased numbers of large tumor spheres and in vivo tumorigenic potential. Our results demonstrated that targeting the maintenance of healthy mitochondria with increased mitochondrial NAD⁺ levels and SIRT3 activity could be a promising strategy for abolishing the development of TICs as a new therapeutic approach to treating aging-associated tumors.
Glioblastoma*
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Lactic Acid
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Metabolism
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Mitochondria
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NAD
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NADP Transhydrogenases
;
Phenotype
;
Tics
;
Up-Regulation*
5.A Case of Fixed Drug Eruption Induced by Tegafur-Uracil(TEGASIL).
Young Soo HEO ; Hae Jun SONG ; Chil Hwan OH
Korean Journal of Dermatology 2010;48(2):155-157
A mixture of tegafur and uracil (TEGASIL) is a common antineoplastic agent. Tegafur is a fluoropyrimidine structurally similar to 5-fluorouracil (5-FU); uracil slows the degradation of 5-FU by dihydropyrimidine dehydrogenase, which results in higher 5-FU concentrations in tumors. Mucocutaneous side effects induced by this agent are rare and include photosensitivity of lichenoid and eczematous types, acral erythema, hyperpigmentation and palmoplantar keratoderma. However, there have been no reports of fixed drug eruption associated with TEGASIL. We report here on a case of fixed drug eruption due to oral TEGASIL.
Dihydrouracil Dehydrogenase (NADP)
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Drug Eruptions
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Erythema
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Fluorouracil
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Hyperpigmentation
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Keratoderma, Palmoplantar
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Tegafur
;
Uracil
6.Effects of Ethanol on the Activities and Inducibility of Trichloroethylene Metabolic Enzyme System in Rat Liver.
Ki Woong KIM ; Seung Kyu KANG ; Young Sook CHO ; Sei Hui LEE ; Young Hahn MOON ; Byung Soon CHOI ; Sang Shin PARK
Korean Journal of Preventive Medicine 1995;28(1):141-152
This study was performed to find out the influences of ethanol on the metabolism of trichloroethylene(TRI) in rats. TRI in corn oil at the dosage of 150, 300, 600 mg/kg was injected peritoneally once a day for two days to two groups. In one group ethanol(4 g/kg) was taken orally 30 minutes before TRI injection, and the other group ethanol was not. The results of experiments are as follows: 1. The contents of cytochrome P-450 and b5 had inverse relationship with in-jected TRI amounts in both groups. 2. The activity of NADPH P-450 reductase was decreased slowly in TRI injected group related with TRI amount, but decreased drastically in the group pretreated with ethanol. 3. The activity of NADH b5 reductase had relationship with injected TRI amount, but the statistical significance was found only in the groups of 300 and 600 mg/kg of TRI injected without relevance to ethanol when compared with the group that was not injected. 4. The activity of ADH was more decreased and ALDH activity was more increased in groups that TRI injected and ethanol was pretreated with ethanol groups than in group without any treatment. These results suggest that ethanol may inhibit epoxide formulation, the first step or TRI metabolism, and change from TCE-OH to TCA also.
Animals
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Corn Oil
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Cytochrome P-450 Enzyme System
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Ethanol*
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Liver*
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Metabolism
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NAD
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NADP
;
Oxidoreductases
;
Rats*
;
Trichloroethylene*
7.Effect of residue Y76 on co-enzyme specificity of meso-diaminopimelate dehydrogenase from Symbiobacterium thermophilum.
Leiming ZHAO ; Weidong LIU ; Xi CHEN ; Min WANG ; Jinhui FENG ; Qiaqing WU ; Dunming ZHU
Chinese Journal of Biotechnology 2015;31(7):1108-1118
In industrial application of NAD(P)H-dependent dehydrogenases, NAD(H) has the advantages over NADP(H) in higher stability, lower price and wider recycling system. Recently, a meso-2,6-diaminopimelate dehydrogenase from Symbiobacterium thermophilum (StDAPDH) has been found to be a useful biocatalyst for the production of D-amino acids, but it requires NADP(H) as co-enzyme. To switch the co-enzyme specificity from NADP(H) to NAD(H), we studied the effect of Y76 on the co-enzyme specificity of StDAPDH, because the crystal structural analysis indicated that residue Y76 is near the adenine ring. The mutation of Y76 exerted significant effect on the co-enzyme specificity. Furthermore, the double mutant R35S/R36V significantly lowered the specific activity toward NADP+, and the combination of R35S/R36V with some of the Y76 mutants resulted in mutant enzymes favorable NAD+ over NADP+. This study should provide useful guidance for the further development of highly active NAD(+)-dependent StDAPDH by enzyme engineering.
Amino Acid Oxidoreductases
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chemistry
;
Amino Acids
;
Clostridiales
;
enzymology
;
Mutation
;
NAD
;
NADP
;
Substrate Specificity
8.Role of Reactive Oxygen Species in Allergic Rhinitis.
Korean Journal of Otolaryngology - Head and Neck Surgery 2012;55(9):541-545
Among many factors explaining recent increase in the prevalence of asthma and allergic rhinitis, role of reactive oxygen species (ROS) during development of these diseases is increasingly considered. Due to their highly reactive nature, ROS produced mainly by the phagocyte nicotinamide adenine dinucleotide phosphate oxidase complex have been considered harmful mediators of inflammation for a long time. However, there are an increasing number of findings suggesting that ROS are anti-inflammatory and prevent autoimmune responses and allergic diseases, thus challenging existing dogma. ROS might not only be produced as a mechanism to eradicate invading pathogens, but rather as a means by which to fine-tune the inflammatory response, depending on when, where and at what amounts they are produced. In this review, the author aim to describe the current findings highlighting ROS as regulators of inflammation, focusing on asthma and allergic rhinitis.
Asthma
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Autoimmunity
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Inflammation
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Inflammation Mediators
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NADP
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Oxidoreductases
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Phagocytes
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Prevalence
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Reactive Oxygen Species
;
Rhinitis
;
Rhinitis, Allergic, Perennial
9.Lignans with NADPH Oxidase 2 (NOX2)-inhibitory Activity from the Fruits of Schisandra chinensis
Jung Min PARK ; Pisey PEL ; Young Won CHIN ; Moo Yeol LEE
Natural Product Sciences 2018;24(1):59-65
An isoform of NADPH oxidase (NOX), NOX2 is a superoxide-generating enzyme involved in diverse pathophysiological events. Although its potential as a therapeutic target has been validated, there is no clinically available inhibitor. Herein, NOX2-inhibitory activity was screened with the constituents isolated from Schisandra chinensis, which has been reported to have antioxidant and reactive oxygen species (ROS)-scavenging effects. Among the partitions prepared from crude methanolic extract, a chloroform-soluble partition showed the highest NOX2-inhibitory activity in PLB-985 cell-based NOX2 assay. A total of twenty nine compounds (1 – 29) were identified from the chloroform fraction, including two first isolated compounds; dimethyl-malate (25) and 2-(2-hydroxyacetyl) furan (27) from this plants. Of these constituents, two compounds (gomisin T, and pregomisin) exhibited an NOX2-inhibitory effect with the IC₅₀ of 9.4 ± 3.6, and 62.9 ± 11.3 µM, respectively. They are confirmed not to be nonspecific superoxide scavengers in a counter assay using a xanthine-xanthine oxidase system. These findings suggest the potential application of gomisin T (6) and other constituents of S. chinensis to inhibit NOX2.
Chloroform
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Fruit
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Lignans
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Methanol
;
NADP
;
NADPH Oxidase
;
Oxidoreductases
;
Reactive Oxygen Species
;
Schisandra
;
Superoxides
10.Cilostazol Attenuates 4-hydroxynonenal-enhanced CD36 Expression on Murine Macrophages via Inhibition of NADPH Oxidase-derived Reactive Oxygen Species Production.
Mi Ran YUN ; Hye Mi PARK ; Kyo Won SEO ; Chae Eun KIM ; Jung Wook YOON ; Chi Dae KIM
The Korean Journal of Physiology and Pharmacology 2009;13(2):99-106
Although anti-atherogenic effects of cilostazol have been suggested, its effects on the expression of SR in macrophages are unclear. This study investigated the role of cilostazol on CD36 expression of murine macrophages enhanced by HNE, a byproduct of lipid peroxidation. The stimulation of macrophages with HNE led to an increased expression of CD36, which was significantly attenuated by NAC, an antioxidant. Moreover, the increased production of ROS by HNE was completely abolished by NADPH oxidase inhibitors, DPI and apocynin, as well as by the 5-LO inhibitor, MK886, but not by inhibitors for other oxidases. This suggested that NADPH-oxidase and 5-LO were major sources of ROS induced by HNE. In addition, HNE-enhanced expression of CD36 was reduced by these inhibitors, which indicated a role for NADPH oxidase and 5-LO on CD36 expression. In our present study, cilostazol was a significant inhibitor of ROS production, as well as CD36 expression induced by HNE. An increase in NADPH oxidase activity by HNE was significantly attenuated by cilostazol, however cilostazol had no effect on HNE-enhanced 5-LO activity. Together, these results suggest that cilostazol attenuates HNE-enhanced CD36 expression on murine macrophages thorough inhibition of NADPH oxidase-derived ROS generation.
Acetophenones
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Lipid Peroxidation
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Macrophages
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NADP
;
NADPH Oxidase
;
Oxidoreductases
;
Reactive Oxygen Species
;
Tetrazoles