406 results on '"Song, Dong Keun"'
Search Results
152. Effects of GABA receptor antagonists injected spinally on antinociception induced by opioids administered supraspinally in mice
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Suh, Hong-Won, primary, Kim, Yung-Hi, additional, Choi, Young-Sun, additional, Choi, Sung-Ran, additional, and Song, Dong-Keun, additional
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- 1996
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153. The reduction of antinociceptive effect of morphine administered intraventricularly is correlated with the decrease of serotonin release from the spinal cord in streptozotocin-induced diabetic rats
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Suh, Hong-Won, primary, Song, Dong-Keun, additional, Wie, Myung-Bok, additional, Jung, Jun-Sub, additional, Hong, Hee-Eun, additional, Choi, Sung-Ran, additional, and Kim, Yung-Hi, additional
- Published
- 1996
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154. Multiplicative interaction between intrathecally and intracerebroventricularly administered morphine for antinociception in the mouse: Effects of spinally and supraspinally injected 3-isobutyl-l-methylxanthine, cholera toxin, and pertussis toxin
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Suh, Hong-Won, primary, Sim, Young-Bo, additional, Choi, Young-Sun, additional, Song, Dong-Keun, additional, and Kim, Yung-Hi, additional
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- 1995
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155. Differential effects of intrathecally injected galanin on antinociception induced by β-endorphin and morphine administered intracerebroventricularly in mice
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Suh, Hong-Won, primary, Song, Dong-Keun, additional, Choi, Yong-Seon, additional, Cheon, Seung-Hwan, additional, and Kim, Yung-Hi, additional
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- 1994
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156. Preventive Agents against Sepsis and New Phenylpropanoid Glucosides from the Fruits of Illicium verum
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Lee, Sung-Won, Li, Gao, Lee, Kyeung Seon, Jung, Jun-Sub, Xu, Ming-Lu, Seo, Chang-Seob, Chang, Hyun-Wook, Kim, Seog-Kyu, Song, Dong-Keun, and Son, Jong-Keun
- Published
- 2003
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157. Protection against β‐amyloid peptide toxicity in vivowith long‐term administration of ferulic acid
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Yan, Ji‐Jing, Cho, Jae‐Young, Kim, Hee‐Sung, Kim, Kyoung‐Li, Jung, Jun‐Sub, Huh, Sung‐Oh, Suh, Hong‐Won, Kim, Yung‐Hi, and Song, Dong‐Keun
- Abstract
β‐Amyloid peptide (Aβ), a 39 – 43 amino acid peptide, is believed to induce oxidative stress and inflammation in the brain, which are postulated to play important roles in the pathogenesis of Alzheimer's disease. Ferulic acid is an antioxidant and anti‐inflammatory agent derived from plants; therefore, the potential protective activity of ferulic acid against Aβ toxicity in vivowas examined.Mice were allowed free access to drinking water (control) or water containing ferulic acid (0.006%). After 4 weeks, Aβ1‐42 (410 pmol) was administered viaintracerebroventricular injection.Injection of control mice with Aβ1‐42 impaired performance on the passive avoidance test (35% decrease in step‐through latency), the Y‐maze test (19% decrease in alternation behaviour), and the water maze test (32% decrease in percentage time in platform‐quadrant). In contrast, mice treated with ferulic acid prior to Aβ1‐42 administration were protected from these changes (9% decrease in step‐through latency; no decrease in alternation behaviour; 14% decrease in percentage time in platform‐quadrant). Aβ1‐42 induced 31% decrease in acetylcholine level in the cortex, which was tended to be ameliorated by ferulic acid.In addition, Aβ1‐42 increased immunoreactivities of the astrocyte marker glial fibrillary acidic protein (GFAP) and interleukin‐1β (IL‐1β) in the hippocampus, effects also suppressed by pretreatment with ferulic acid.Administration of ferulic acid per seunexpectedly induced a transient and slight increase in GFAP and IL‐1β immunoreactivity in the hippocampus on day 14, which returned to basal levels on day 28. A slight (8%) decrease in alternation behaviour was observed on day 14.These results demonstrate that long‐term administration of ferulic acid induces resistance to Aβ1‐42 toxicity in the brain, and suggest that ferulic acid may be a useful chemopreventive agent against Alzheimer's disease.
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- 2001
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158. Cycloheximide Increases Proenkephalin and Tyrosine Hydroxylase Gene Expression in Rat Adrenal Medulla1
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Won, Je-Seong, Lee, Jin-Koo, Song, Dong-Keun, Huh, Sung-Oh, Jung, Jun-Sub, Kim, Yung-Hi, Choi, Mi-Ran, and Suh, Hong-Won
- Abstract
The effect of cycloheximide (CHX; 5 mg/kg) on proenkephalin (proENK) and tyrosine hydroxylase (TH) mRNA expression in rat central and peripheral nervous systems was studied. CHX increased proENK and TH mRNA levels in the adrenal gland, but not in hippocampus, striatum, midbrain, brainstem, pituitary, and hypothalamus. The pretreatment with actinomycin D (0.5 mg/kg) significantly decreased CHX-induced proENK and TH mRNA expression, suggesting that the CHX-dependent increase of these mRNA levels may be caused by the increase of transcriptional activity rather than RNA stabilization. To investigate the factors involved in CHX-induced proENK and TH mRNA expression, the effect of CHX on activator protein-1 (AP-1), cAMP response element (CRE) binding protein (CREB), and glucocorticoid response element (GRE) was tested. In AP-1, the basal expression of Fra-2 and c-Jun proteins and AP-1 DNA binding activity in the adrenal medulla was higher than other tissues tested, but CHX reduced these protein levels and AP-1 DNA binding activity. In CREB, CHX time dependently increased the level of phospho-CREB without altering total CRE level and CRE DNA binding activity. Furthermore, phospho-CREB actively participated in CRE DNA binding activity. In GRE, although CHX increased plasma and adrenal corticosterone level, RU486 (10 mg/kg) reduced CHX-induced proENK, but not TH, mRNA level in a partial manner. These results suggest that the basal expression of proENK and TH mRNA transcription in the adrenal gland seems to be tonically inhibited by de novo protein synthesis. In addition, CHX-dependent increase of proENK and TH mRNA expression in the adrenal medulla is well correlated with phospho-CREB level, but not AP-1. Finally, glucocorticoid seems to be involved at least partially in CHX-dependent proENK, but not TH, mRNA expression in the adrenal medulla.
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- 2000
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159. Central GABAAand GABABReceptor Modulation of Basal and Stress-Induced Plasma Interleukin-6 Levels in Mice1
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Song, Dong-Keun, Suh, Hong-Won, Huh, Sung-Oh, Jung, Jun-Sub, Ihn, Bong-Moo, Choi, Ihn-Geun, and Kim, Yung-Hi
- Abstract
To investigate the modulatory roles of central γ-aminobutyric acid (GABA)Aand GABABreceptors in the regulation of basal and stress-induced plasma interleukin-6 (IL-6) levels, we examined the effects of i.c.v. injection of GABA receptor agonists and antagonists on basal and restraint stress-induced plasma IL-6 levels in mice. Muscimol (20–200 ng), a GABAAreceptor agonist, and baclofen (5–20 ng), a GABABreceptor agonist, injected i.c.v. did not affect the basal levels of plasma IL-6. In the restraint-stressed animals, muscimol and baclofen inhibited the stress-induced plasma IL-6 levels from the dose of 50 and 15 ng, respectively. 2-(3-Carboxyl)-3-amino-6-(4-methoxyphenyl)-pyridazinium bromide (SR-95,531; 0.3–10 ng), a GABAAreceptor antagonist, and 2-hydroxysaclofen (1–10 μg), a GABABreceptor antagonist, injected i.c.v. increased both the basal and the restraint stress-induced plasma IL-6 levels. The i.p. pretreatment of animals with 6-hydroxydopamine (100 mg/kg) for 3 days significantly inhibited SR-95,531 (3 ng i.c.v.)- but not 2-hydroxysaclofen (10 μg i.c.v.)-induced increase in the basal plasma IL-6 levels. These data suggest that central GABAAand GABABreceptors are involved in the suppressive modulation of basal and restraint stress-induced plasma IL-6 levels in mice.
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- 1998
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160. Inhibition of stressinduced plasma corticosterone levels by ginsenosides in mice
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Kim, Do Hoon, Jung, Jun Sub, Suh, Hong Won, Huh, Sung Oh, Min, Sung-Kil, Son, Bong Ki, Park, Jung Hill, Kim, Nak Doo, Kim, Yung Hi, and Song, Dong Keun
- Abstract
GINSENG total saponins (GTS) injected intracere-broventricularly (i.c.v.) at doses of 0.1–1 μg inhibited the i.c.v. injection stress-induced plasma corticosterone levels in mice. The inhibitory action of GTS was blocked by co-administered NG-nitro-L-arginine methyl ester (L-NAME; 1.5 μg, i.c.v.), an inhibitor of nitric oxide synthase (NOS). Of the ginsenosides Rb1, Rb2, Rc, Rd, Re, Rf, Rg1, 20(S)-Rg3and 20(R)-Rg3injected i.c.v. at doses of 0.01–1 μg, 20(S)-Rg3and Rc significantly inhibited the i.c.v. injection stress-induced plasma corticosterone levels. The inhibitory actions of 20(S)-Rg3and Rc were blocked by co-administered L-NAME (1.5 μg, i.c.v.). These results suggest that GTS, 20(S)-Rg3and Rc may inhibit the i.c.v. injection stress-induced hypothalamo-pituitary-adrenal response by inducing NO production in the brain.
- Published
- 1998
161. High production of CH4 and H2 by reducing PET waste water using a non-diaphragm-based electrochemical method.
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Kim, Nam-Gyu, Yim, Kwang-Jin, Kim, Chan-Soo, Song, Dong-Keun, Okuyama, Kikuo, Han, Min-ho, Kim, Young-hoo, Lee, Sung-Eun, and Kim, Tae-Oh
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- 2016
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162. Angiotensin converting enzyme inhibitors and angiotensin II receptor antagonist attenuate tumor growth via polarization of neutrophils toward an antitumor phenotype.
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Shrestha, Sanjeeb, Kim, Shin-Yeong, Ham, Hwa-Yong, Kim, Yeon-Ja, Yun, Young-Jin, Song, Dong-Keun, Hong, Chang-Won, Noh, Jae Myoung, Kim, Min-Ju, and Kwon, Min-Soo
- Subjects
ACE inhibitors ,ANGIOTENSIN-receptor blockers ,NATURAL immunity ,SUPPRESSOR cells ,NEUTROPHILS ,TUMOR immunology - Abstract
Tumor microenvironments polarize neutrophils to protumoral phenotypes. Here, we demonstrate that the angiotensin converting enzyme inhibitors (ACEis) and angiotensin II type 1 receptor (AGTR1) antagonist attenuate tumor growth via polarization of neutrophils toward an antitumoral phenotype. The ACEis or AGTR1 antagonist enhanced hypersegmentation of human neutrophils and increased neutrophil cytotoxicity against tumor cells. This neutrophil hypersegmentation was dependent on the mTOR pathway. In a murine tumor model, ACEis and AGTR1 antagonist attenuated tumor growth and enhanced neutrophil hypersegmentation. ACEis inhibited tumor-induced polarization of neutrophils to a protumoral phenotype. Neutrophil depletion reduced the antitumor effect of ACEi. Together, these data suggest that the modulation of Ang II pathway attenuates tumor growth via polarization of neutrophils to an antitumoral phenotype. [ABSTRACT FROM PUBLISHER]
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- 2016
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163. The effects of protection by D-Pen 2-D-Pen 5-enkephalin or D-Ala 2-NMePhe 4-Gly-ol-enkephalin against β-chlornaltrexamine in the spinal cord on the antinociception induced by β-endorphin administered intracerebroventricularly in the mouse
- Author
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Suh, Hong-Won, Lim, Jae-Sun, Song, Dong-Keun, Kim, Yung-Hi, and Tseng, Leon-Fu
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- 1994
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164. Effects of intraventricular injection of morphine and β-endorphin on serotonin release from the spinal cord in rats
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Jung, Jun-Sub, Song, Dong-Keun, Suh, Hong-Won, and Kim, Yung-Hi
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- 1994
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165. Effect of temperature on carbon nanoparticle collection efficiency using photoelectric ESP
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Kim, Woojin, Jung, Jae Hee, Song, Dong Keun, Kim, Hakjoon, Kim, Yong Jin, and Kim, Sang Soo
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NANOPARTICLES , *CARBON , *ELECTROSTATIC precipitation , *PHOTOELECTRICAL research , *NANOSTRUCTURED materials , *PARTICULATE matter , *DIESEL motor exhaust gas - Abstract
The electrostatic precipitator (ESP) technique is a promising method for enhancing the particulate matter (PM) emission reduction efficiency of diesel engines, and is much better than the diesel particulate filter (DPF) technique. However, the ESP''s low efficiency in collecting PM with diameters less than several tens of nanometers remains a problem because the particle charging efficiency decreases as the size of the nanoparticles decreases. To improve the collection efficiency of nanosized PM, we used a photoelectric charger to increase the charging efficiency of nanoparticles ahead of the ESP system. Carbon nanoparticles produced using a spark discharge generator were used to evaluate the collection efficiency of the combined photoelectric charger and ESP system. The particle sizes were measured using a scanning mobility particle sizer system at various experimental temperatures similar to the temperature of DPF systems commonly used in diesel engines. We succeeded in obtaining improved collection efficiencies at increased inner temperatures of the photoelectric charging chamber. As the temperature increased from 694 °C to 839 °C at the inlet of the photoelectric chamber, the efficiency of PM collection improved significantly to 28.5% for a particle diameter of 18.4 nm. [Copyright &y& Elsevier]
- Published
- 2009
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166. Dexmedetomidine combined with suprascapular nerve block and axillary nerve block has a synergistic effect on relieving postoperative pain after arthroscopic rotator cuff repair.
- Author
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Lee, Jae Jun, Kim, Do-Young, Hwang, Jung-Taek, Song, Dong-Keun, Lee, Han Na, Jang, Ji Su, Lee, Sang-Soo, Hwang, Sung Mi, Moon, Sung Hoon, and Shim, Jae-Hoon
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NERVE block , *POSTOPERATIVE pain , *ROTATOR cuff surgery , *CYTOKINES , *DEXMEDETOMIDINE - Abstract
Purpose: Suprascapular nerve block (SSNB) is the most commonly used block for the relief of postoperative pain from arthroscopic rotator cuff repair and can be used in combination with axillary nerve block (ANB). Dexmedetomidine (DEX) is a type of alpha agonist that can elongate the duration of regional block. The aim of this study was to compare the effects of the use of dexmedetomidine combined with SSNB and ANB with those of the use of SSNB and ANB alone on postoperative pain, satisfaction, and pain-related cytokines within the first 48 h after arthroscopic rotator cuff repair. Methods: Forty patients with rotator cuff tears who had undergone arthroscopic rotator cuff repair were enrolled in this single-center, double-blinded randomized controlled trial study. Twenty patients were randomly allocated to group 1 and received ultrasound-guided SSNB and ANB using a mixture of 0.5 ml (50 μg) of DEX and 9.5 ml of 0.75% ropivacaine preemptively. The other 20 patients were allocated to group 2 and underwent ultrasound-guided SSNB and ANB alone using a mixture of 0.5 ml of normal saline and 9.5 ml of ropivacaine. The visual analog scale (VAS) for pain and patient satisfaction (SAT) scores were postoperatively checked within 48 h. The plasma interleukin (IL)-6, IL-8, IL-1β, cortisol, and serotonin levels were also postoperatively measured within 48 h. Results: Group 1 showed a significantly lower mean VAS (visual analog scale of pain) score 1, 3, 6, 12, 18 and 24 h after operation, and a significantly higher mean SAT (patient satisfaction) score 1, 3, 6, 12, 18, 24 and 36 h after the operation than group 2. Group 1 showed a significantly lower mean plasma IL-8 level 1 and 48 h after the operation, and a significantly lower mean IL-1β level 48 h after the operation than group 2. Group 1 showed a significantly lower mean plasma serotonin level 12 h after the operation than group 2. The mean timing of rebound pain in group 1 was significantly later than that in group 2 (36 h > 23 h, p = 0.007). Six patients each in groups 1 and 2 showed rebound pain. The others did not show rebound pain. Conclusions: Ultrasound-guided SSNA and ANB with DEX during arthroscopic rotator cuff repair resulted in a significantly lower mean VAS score and a significantly higher mean SAT score within 48 h after the operation than SSNB and ANB alone. Additionally, SSNB and ANB with DEX tended to result in a later mean timing of rebound pain accompanied by significant changes in IL-8, IL-1β, and serotonin levels within 48 h after the operation. The present study could provide the basis for selecting objective parameters of postoperative pain in deciding the optimal use of medication for relieving pain. Level of Evidence: Level I. Trial Registration: 2015–20, ClinicalTrials.gov Identifier: NCT04398589. IRB number: 2015–20, Hallym University Chuncheon Sacred Heart Hospital. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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167. Extracellular vesicles from dHL-60 cells as delivery vehicles for diverse therapeutics.
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Kim, Jun-Kyu, Youn, Young-Jin, Lee, Yu-Bin, Kim, Sun-Hwa, Song, Dong-Keun, Shin, Minsang, Jin, Hee Kyung, Bae, Jae-sung, Shrestha, Sanjeeb, and Hong, Chang-Won
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VESICLES (Cytology) , *CELL communication , *DRUG delivery systems , *NEUTROPHILS , *LEUKEMIA - Abstract
Extracellular vesicles (EVs) are membrane-derived heterogeneous vesicles that mediate intercellular communications. They have recently been considered as ideal vehicles for drug-delivery systems, and immune cells are suggested as a potential source for drug-loaded EVs. In this study, we investigated the possibility of neutrophils as a source for drug-loaded EVs. Neutrophil-like differentiated human promyelocytic leukemia cells (dHL-60) produced massive amounts of EVs within 1 h. The dHL-60 cells are also easily loaded with various cargoes such as antibiotics (penicillin), anticancer drug (paclitaxel), chemoattractant (MCP-1), miRNA, and Cas9. The EVs derived from the dHL-60 cells showed efficient incorporation of these cargoes and significant effector functions, such as bactericidal activity, monocyte chemotaxis, and macrophage polarization. Our results suggest that neutrophils or neutrophil-like promyelocytic cells could be an attractive source for drug-delivery EVs. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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168. Dexmedetomidine combined with interscalene brachial plexus block has a synergistic effect on relieving postoperative pain after arthroscopic rotator cuff repair.
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Hwang, Jung-Taek, Jang, Ji Su, Lee, Jae Jun, Song, Dong-Keun, Lee, Han Na, Kim, Do-Young, Lee, Sang-Soo, Hwang, Sung Mi, Kim, Yong-Been, and Lee, Sanghyeon
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DEXMEDETOMIDINE , *BRACHIAL plexus block , *ROTATOR cuff surgery , *POSTOPERATIVE pain , *ROPIVACAINE - Abstract
Purpose: Interscalene brachial plexus block (ISB) is one of the most commonly used regional blocks in relieving postoperative pain after arthroscopic rotator cuff repair. Dexmedetomidine (DEX) is an alpha 2 agonist that can enhance the effect of regional blocks. The aim of this study was to compare the effects of DEX combined with ISB with ISB alone on postoperative pain, satisfaction, and pain-related cytokines within the first 48 h after arthroscopic rotator cuff repair.Methods: Fifty patients with rotator cuff tears who had undergone arthroscopic rotator cuff repair were enrolled in this single center, double-blinded randomized controlled trial study. Twenty-five patients were randomly allocated to group 1 and received ultrasound-guided ISB using a mixture of 1 ml (100 μg) of DEX and 8 ml of 0.75% ropivacaine preemptively. The other 25 patients were allocated to group 2 and underwent ultrasound-guided ISB alone using a mixture of 1 ml of normal saline and 8 ml of ropivacaine. The visual analog scale (VAS) for pain and patient satisfaction (SAT) scores were checked within 48 h postoperatively. The plasma interleukin (IL)-6, -8, -1β, cortisol, and substance P levels were also measured within 48 h, postoperatively.Results: Group 1 showed a significantly lower mean VAS score and a significantly higher mean SAT score than group 2 at 1, 3, 6, 12, and 18 h postoperatively. Compared with group 2, group 1 showed a significantly lower mean plasma IL-6 level at 1, 6, 12, and 48 h postoperatively and a significantly lower mean IL-8 level at 1, 6, 12, 24, and 48 h postoperatively. The mean timing of rebound pain in group 1 was significantly later than that in group 2 (12.7 h > 9.4 h, p = 0.006).Conclusions: Ultrasound-guided ISB with DEX in arthroscopic rotator cuff repair led to a significantly lower mean VAS score and a significantly higher mean SAT score within 48 h postoperatively than ISB alone. In addition, ISB with DEX showed lower mean plasma IL-6 and IL-8 levels than ISB alone within 48 h postoperatively, with delayed rebound pain.Level Of Evidence: I.Trial Registration: 2013-112, ClinicalTrials.gov Identifier: NCT02766556. [ABSTRACT FROM AUTHOR]- Published
- 2020
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169. Improvement of NASH and liver fibrosis through modulation of the gut-liver axis by a novel intestinal FXR agonist.
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Moon, An-Na, Briand, François, Breyner, Natalia, Song, Dong-Keun, Madsen, Martin Rønn, Kim, Hongbin, Choi, Keonwoo, Lee, Yoonsuk, and Namkung, Wan
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HEPATIC fibrosis , *ITCHING , *FARNESOID X receptor , *NON-alcoholic fatty liver disease , *G protein coupled receptors , *BILE acids - Abstract
Farnesoid X receptor (FXR) plays a pivotal role in the regulation of bile acid homeostasis and is involved in the pathogenesis of nonalcoholic steatohepatitis (NASH). Although FXR agonists effectively alleviate pathological features of NASH, adverse effects such as disturbance of cholesterol homeostasis and occurrence of pruritus remain to be addressed. Here, we identified a novel FXR agonist, ID119031166 (ID166), and explored the pharmacological benefits of ID166 in the treatment of NASH. ID166, a potent and selective non-bile acid FXR agonist, exhibits preferential distribution in the intestine and shows no agonist activity against potential itch receptors including Mas-related G protein-coupled receptor X4 (MRGPRX4). Interestingly, ID166 significantly attenuated total nonalcoholic fatty liver disease (NAFLD) activity and liver fibrosis in a free choice diet-induced NASH hamster model. In addition, ID166 drastically modulated the relative abundance of five gut microbes and reduced the increase in plasma total bile acid levels to normal levels in NASH hamsters. Moreover, long-term treatment with ID166 significantly improved key histological features of NASH and liver fibrosis in a diet-induced NASH mouse model. In the NASH mouse livers, RNA-seq analysis revealed that ID166 reduced the gene expression changes associated with both NASH and liver fibrosis. Notably, ID166 exhibited no substantial effects on scratching behavior and serum IL-31 levels in mice. Our findings suggest that ID166, a novel FXR agonist with improved pharmacological properties, provides a preclinical basis to optimize clinical benefits for NASH drug development. [Display omitted] • ID166, a novel non-bile acid FXR agonist preferentially distributed to intestine. • ID166 improves NASH and liver fibrosis along with plasma LDL-C reduction. • ID166 increases the population of the most widely used traditional probiotics. • ID166 has no effect on the pruritogenic bile acid receptors TGR5 and MRGPRX4. [ABSTRACT FROM AUTHOR]
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- 2024
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170. Alteration of Lysophosphatidylcholine-Related Metabolic Parameters in the Plasma of Mice with Experimental Sepsis.
- Author
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Ahn, Won-Gyun, Jung, Jun-Sub, Kwon, Hyeok Yil, and Song, Dong-Keun
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SEPTICEMIA treatment , *LECITHIN , *PHOSPHOLIPASES , *AUTOTAXIN , *BLOOD plasma , *LABORATORY mice - Abstract
Plasma concentration of lysophosphatidylcholine (LPC) was reported to decrease in patients with sepsis. However, the mechanisms of sepsis-induced decrease in plasma LPC levels are not currently well known. In mice subjected to cecal ligation and puncture (CLP), a model of polymicrobial peritoneal sepsis, we examined alterations in LPC-related metabolic parameters in plasma, i.e., the plasma concentration of LPC-related substances ( i.e., phosphatidylcholine (PC) and lysophosphatidic acid (LPA)), and activities or levels in the plasma of some enzymes that can be involved in the regulation of plasma LPC concentration ( i.e., secretory phospholipase A2 (sPLA2), lecithin:cholesterol acyltransferase (LCAT), acyl-CoA:lysophosphatidylcholine acyltransferase (LPCAT), and autotaxin (ATX)), as well as plasma albumin concentration. We found that levels of LPC and albumin and enzyme activities of LCAT, ATX, and sPLA2 were decreased, whereas levels of PC, LPA, and LPCAT1-3 were increased in the plasma of mice subjected to CLP. Bacterial peritonitis led to alterations in all the measured LPC-related metabolic parameters in the plasma, which could potentially contribute to sepsis-induced decrease in plasma LPC levels. These findings could lead to the novel biomarkers of sepsis. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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171. Differential antagonism by MK-801 against antinociception induced by opioid receptor agonists administered supraspinally in mice
- Author
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Suh, Hong-Won, Song, Dong-Keun, Kim, Yung-Hi, Yoo, Jang-Soo, and Tseng, Leon F
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- 1994
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172. Retinoic acid induces hypersegmentation and enhances cytotoxicity of neutrophils against cancer cells.
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Shrestha, Sanjeeb, Kim, Shin-Yeong, Yun, Young-Jin, Kim, Jun-Kyu, Lee, Jae Man, Shin, Minsang, Song, Dong-Keun, and Hong, Chang-Won
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TRETINOIN , *CELL-mediated cytotoxicity , *NEUTROPHILS , *CANCER cells , *CELL separation - Abstract
Hypersegmentation of nuclei is considered a distinct characteristic of the antitumoral phenotype of neutrophils. Retinoic acid, a metabolite of retinol, reorganizes and induces segmentation of the nucleus during the differentiation of neutrophils. However, the role of retinoic acid in the phenotype polarization of neutrophils has not been fully established. Here, we investigated the effect of retinoic acid on phenotype polarization of neutrophils. Retinoic acid-induced the hypersegmentation of human neutrophils via retinoic acid receptors and mTOR pathways. Retinoic acid-induced hypersegmented neutrophils enhanced neutrophil extracellular traps (NETs) formation in response to phorbol-12-myristate 13-acetate (PMA) and fMLP (N-Formylmethionine-leucyl-phenylalanine) stimulation, and increased cytotoxicity against various tumor cells. Moreover, retinoic acid treatment attenuated tumor growth in a murine model of tumor. Taken together, these results suggests that retinoic acid induces the phenotype polarization of neutrophils to exert antitumor effects. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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173. Protective effects of a dimeric derivative of ferulic acid in animal models of Alzheimer's disease.
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Jung, Jun-Sub, Yan, Ji-Jing, Li, Hong-Mei, Sultan, Md. Tipu, Yu, Jaehoon, Lee, Hee-Sul, Shin, Kye-Jung, and Song, Dong-Keun
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FERULIC acid , *CHEMICAL derivatives , *ANTIOXIDANTS , *ALZHEIMER'S disease treatment , *ANIMAL models in research , *DRUG administration , *Y maze - Abstract
Ferulic acid is a compound with potent anti-oxidant and anti-inflammatory activities. We previously reported the protective effects of ferulic acid administration against two animal models of Alzheimer's disease (AD): intracerebroventricular (i.c.v.) injection of Aß1-42 in mice and APP/PS1 mutant transgenic mice. In this study using the same AD animal models, we examined the effect of KMS4001, one of dimeric derivatives of ferulic acid. Intragastric pretreatment of mice with KMS4001 (30 mg/kg/day) for 5 days significantly attenuated the Aß1-42 (i.c.v.)-induced memory impairment both in passive avoidance test and in Y-maze test. APP/PS1 mutant transgenic mice at KMS4001 doses of 3 and 30 mg/kg/day via drinking water showed the significantly enhanced novel-object recognition memory at both 1.5 and 3 months after the start of KMS4001 treatment. Treatment of APP/PS1 mutant transgenic mice with KMS4001 for 3 months at the doses of 3 and 30 mg/kg/day markedly decreased Aβ1-40 and Aβ1-42 levels in the frontal cortex. The KMS4001 dose-response relationships for Aβ decrease and for improvement in novel-object recognition test corresponded to each other. Taken together, these results suggest that KMS4001 could be an effective drug candidate against AD. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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174. Zirconium Oxide Post-treatment for TiO2 Photoelectrodes in Dye-Sensitized Solar Cells.
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Kim, Beom-Soo, Park, Jun-Yong, Kim, Chan-Soo, Kim, Seong-Bum, Song, Dong-Keun, Jang, Hee-Dong, Lee, Sung-Eun, and Kim, Tae-Oh
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DYE-sensitized solar cells , *ZIRCONIUM oxide , *TITANIUM dioxide , *ELECTRODES , *ENERGY conversion , *CALCINATION (Heat treatment) - Abstract
Zirconium was newly utilized as a post-treatment material for photoelectrodes in dye-sensitized solar cells (DSSCs), and DSSCs with a high energy conversion efficiency were developed. The Zr oxide-post-treated TiO 2 photoelectrodes were prepared by dipping Degussa P25 in a Zr butoxide solution, followed by calcination for 30 min at 475 °C. In the prepared sample, the particle size decreased, and the specific surface area increased, leading to improved dye adsorption. Zr oxide-post-treatment formed ZrO 2 on TiO 2 surfaces and the electron transport increased by the formation. This post-treatment decreased the recombinant ratio of electrons by reducing resistance in the interparticle electrode/dye/electrolyte. The energy conversion efficiency of Zr oxide-post-treated TiO 2 photoelectrodes was 7.03%, which is a 61% improvement over P25 photoelectrodes and is similar to that of TiCl 4 -post-treated TiO 2 photoelectrodes (7.28%). This enhanced energy conversion efficiency could be attributed to the increased surface area, which enabled higher dye loading, and to the improved interparticle connections, which enhanced charge transport and reduced charge recombination. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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175. 1,3-Oxazine as a chiral building block used in the total synthesis of (+)-1-deoxynojirimycin and (2R,5R)-dihydroxymethyl-(3R,4R)-dihydroxypyrrolidine.
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Park, Seok-Hwi, Kim, Ji-Yeon, Kim, Jin-Seok, Jung, Changyoung, Song, Dong-Keun, and Ham, Won-Hun
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OXAZINES , *CHIRALITY , *ALPHA-glucosidases , *PYRROLIDINE , *CHEMICAL synthesis , *DIASTEREOISOMERS - Abstract
Concise and stereocontrolled syntheses of (+)-1-deoxynojirimycin and (2 R ,5 R )-dihydroxymethyl-(3 R ,4 R )-dihydroxypyrrolidine [(+)-DMDP] were achieved via a diastereomerically enriched oxazine intermediate. The key strategies include the use of 1,3-oxazine as a chiral building block and diastereoselective nucleophilic addition to an aldehyde. Starting from readily available ( R )-methyl 2-benzamido-3-(( tert -butyldimethylsilyl)oxy)propanoate, (+)-1-deoxynojirimycin was synthesized in 11 steps and 26.2% overall yield while (+)-DMDP was synthesized in 11 steps and 27.1% overall yield, respectively. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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- View/download PDF
176. Sulfur mustard primes human neutrophils for increased degranulation and stimulates cytokine release via TRPM2/p38 MAPK signaling
- Author
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Song, Dong-Keun [Department of Pharmacology, Infectious Diseases Medical Research Center, College of Medicine, Hallym University, Chuncheon (Korea, Republic of)]
- Published
- 2012
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177. Methoxy Poly(ethylene glycol)-Poly(lactide) Nanoparticles Encapsulating Quercetin Act as an Effective Anticancer Agent by Inducing Apoptosis in Breast Cancer.
- Author
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Sharma, Garima, Park, Jongbong, Sharma, Ashish Ranjan, Jung, Jun-Sub, Kim, Haesung, Chakraborty, Chiranjib, Song, Dong-Keun, Lee, Sang-Soo, and Nam, Ju-Suk
- Subjects
- *
BREAST cancer treatment , *METHOXY compounds , *POLYETHYLENE glycol , *POLYLACTIC acid , *NANOMEDICINE , *QUERCETIN , *ANTINEOPLASTIC agents , *APOPTOSIS , *THERAPEUTICS - Abstract
Purpose: To overcome the therapeutic restrictions offered by hydrophobic quercetin (Qu), this study aims to synthesize MPEG-PLA encapsulated Qu nanoparticle and to evaluate their anticancer efficacy. Materials and Methods: In vitro anticancer potential and apoptotic studies were done by cell cytotoxicity assay and flow cytometry, respectively . MPEG-PLA-Qu nanoparticles were evaluated for anticancer efficacy in vivo using xenograft mice model. TUNEL assay was performed to observe the frequency of apoptotic cells in vivo. Results: The hydrodynamic particle size, polydispersity index, zeta potential and drug loading % of MPEG-PLA-Qu nanoparticle was 155.3 ± 3.2 nm, 0.2 ± 0.05, −3.14 mV and 5.3 ± 1.1%, respectively. Also, MPEG-PLA-Qu showed sustained drug release for 10 days. In vitro results showed that MPEG-PLA-Qu could efficiently induce apoptosis in triple negative breast cancer cell line (MDA-MB-231) with higher amount of quercetin in cell lysate treated with MPEG-PLA-Qu in comparison to free quercetin. In xenograft model for breast cancer, peritumorally injected MPEG-PLA-Qu significantly inhibited the tumor growth. Moreover, TUNEL assay showed more occurrence of apoptotic cells in MPEG-PLA-Qu treated tumors compared to free quercetin at similar dose. Conclusion: Our data suggest that MPEG-PLA-Qu nanoparticle can have a promising clinical potential for the treatment of breast cancer. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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- View/download PDF
178. FcγRIIb mediates amyloid-β neurotoxicity and memory impairment in Alzheimer's disease.
- Author
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Kam, Tae-In, Song, Sungmin, Gwon, Youngdae, Park, Hyejin, Yan, Ji-Jing, Im, Isak, Choi, Ji-Woo, Choi, Tae-Yong, Kim, Jeongyeon, Song, Dong-Keun, Takai, Toshiyuki, Kim, Yong-Chul, Kim, Key-Sun, Choi, Se-Young, Choi, Sukwoo, Klein, William L, Yuan, Junying, and Jung, Yong-Keun
- Abstract
Amyloid-β (Aβ) induces neuronal loss and cognitive deficits and is believed to be a prominent cause of Alzheimer's disease (AD); however, the cellular pathology of the disease is not fully understood. Here, we report that IgG Fcγ receptor II-b (FcγRIIb) mediates Aβ neurotoxicity and neurodegeneration. We found that FcγRIIb is significantly upregulated in the hippocampus of AD brains and neuronal cells exposed to synthetic Aβ. Neuronal FcγRIIb activated ER stress and caspase-12, and Fcgr2b KO primary neurons were resistant to synthetic Aβ-induced cell death in vitro. Fcgr2b deficiency ameliorated Aβ-induced inhibition of long-term potentiation and inhibited the reduction of synaptic density by naturally secreted Aβ. Moreover, genetic depletion of Fcgr2b rescued memory impairments in an AD mouse model. To determine the mechanism of action of FcγRIIb in Aβ neurotoxicity, we demonstrated that soluble Aβ oligomers interact with FcγRIIb in vitro and in AD brains, and that inhibition of their interaction blocks synthetic Aβ neurotoxicity. We conclude that FcγRIIb has an aberrant, but essential, role in Aβ-mediated neuronal dysfunction. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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179. Synthesis and photocatalytic activity of N-doped TiO2/ZrO2 visible-light photocatalysts
- Author
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Cha, Ji-An, An, Sang-Hun, Jang, Hee-Dong, Kim, Chan-Soo, Song, Dong-Keun, and Kim, Tae-Oh
- Subjects
- *
PHOTOCATALYTIC oxidation , *CHEMICAL synthesis , *PHOTOCATALYSIS , *NITROGEN , *PHOTODEGRADATION , *SPECTRUM analysis , *TRANSMISSION electron microscopy - Abstract
Abstract: Visible-light responsive N-doped ZrO2/TiO2 photocatalysts were synthesized via a sol–gel process. To obtain the optimum nitrogen doping content and operational conditions for photodegradation of NO, several key factors (including nitrogen doping, initial NO concentration, light intensity, reactor temperature, etc.) were investigated under both UV and visible light irradiation. Physical characterization of the photocatalysts was performed using X-ray diffraction (XRD), UV–visible absorption spectroscopy, transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT-IR). The observed results suggest that nitrogen was doped in the lattice of TiO2 and had an effect on the translation of phase, photodegradation activity, and visible-light response. Among synthesized photocatalysts, 0.1M Zr and 0.15M N supported on TiO2 exhibited the best visible-light response and the highest NO photodegradation activity. [Copyright &y& Elsevier]
- Published
- 2012
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180. The effect of TNFα secreted from macrophages activated by titanium particles on osteogenic activity regulated by WNT/BMP signaling in osteoprogenitor cells
- Author
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Lee, Sang-Soo, Sharma, Ashish R., Choi, Byung-Soo, Jung, Jun-Sub, Chang, Jun-Dong, Park, Seonghun, Salvati, Eduardo A., Purdue, Edward P., Song, Dong-Keun, and Nam, Ju-Suk
- Subjects
- *
TUMOR necrosis factors , *MACROPHAGE activation , *BONE growth , *OSTEOBLASTS , *CELLULAR signal transduction , *BONE resorption , *TITANIUM , *ARTIFICIAL joints - Abstract
Abstract: Wear particles are the major cause of osteolysis associated with failure of implant following total joint replacement. During this pathologic process, activated macrophages mediate inflammatory responses to increase osteoclastogenesis, leading to enhanced bone resorption. In osteolysis caused by wear particles, osteoprogenitors present along with macrophages at the implant interface may play significant roles in bone regeneration and implant osteointegration. Although the direct effects of wear particles on osteoblasts have been addressed recently, the role of activated macrophages in regulation of osteogenic activity of osteoblasts has scarcely been studied. In the present study, we examined the molecular communication between macrophages and osteoprogenitor cells that may explain the effect of wear particles on impaired bone forming activity in inflammatory bone diseases. It has been demonstrated that conditioned medium of macrophages challenged with titanium particles (Ti CM) suppresses early and late differentiation markers of osteoprogenitors, including alkaline phosphatase (ALP) activity, collagen synthesis, matrix mineralization and expression of osteocalcin and Runx2. Moreover, bone forming signals such as WNT and BMP signaling pathways were inhibited by Ti CM. Interestingly, TNFα was identified as a predominant factor in Ti CM to suppress osteogenic activity as well as WNT and BMP signaling activity. Furthermore, Ti CM or TNFα induces the expression of sclerostin (SOST) which is able to inhibit WNT and BMP signaling pathways. It was determined that over-expression of SOST suppressed ALP activity, whereas the inhibition of SOST by siRNA partially restored the effect of Ti CM on ALP activity. This study highlights the role of activated macrophages in regulation of impaired osteogenic activity seen in inflammatory conditions and provides a potential mechanism for autocrine regulation of WNT and BMP signaling mediated by TNFα via induction of SOST in osteprogenitor cells. [Copyright &y& Elsevier]
- Published
- 2012
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181. Small GTPases Rap1 and RhoA regulate superoxide formation by Rac1 GTPases activation during the phagocytosis of IgG-opsonized zymosans in macrophages
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Li, Yi, Kim, Jae-Gyu, Kim, Hee-Jun, Moon, Mi-Young, Lee, Jae-Yong, Kim, Jaebong, Kim, Sung-Chan, Song, Dong-Keun, Kim, Yong-Sun, and Park, Jae-Bong
- Subjects
- *
GUANOSINE triphosphatase , *SUPEROXIDES , *PHAGOCYTOSIS , *MACROPHAGES , *NADPH oxidase , *CYTOCHROME b , *NEUTROPHILS , *LYSOPHOSPHOLIPIDS - Abstract
Abstract: Phagocytic NADPH oxidase plays a critical role in superoxide generation in macrophage cells. Small GTPases, including Rac1 and Rac2, have been implicated in the regulation of NADPH oxidase activity. Rap1, which has no effect in a cell-free system of oxidase activation, recently has been proven to colocalize with cytochrome b 558. In addition, neutrophils from rap1A-/- mice reduce fMLP-stimulated superoxide production. Here, we tried to determine whether Rap1 also plays a role in the production of superoxide. IgG-opsonized zymosan (IOZ) particles treatment induced Rap1 activation and superoxide generation. Knock-down of Rap1 by si-Rap1 suppressed IOZ-induced superoxide formation. Sh-RhoA also reduced superoxide levels, but 8CPT-2Me-cAMP, an activator of Epac1 (a guanine nucleotide exchange factor (GEF) of Rap1), could recover the levels to the control value. When cells were stimulated by IOZ, Rap1 and Rac1 were translocated to the membrane, and then interacted with p22phox. 8CPT-2Me-cAMP rescued sh-RhoA-induced reduction of the interaction between Rac1 and p22phox, and enhanced lysophosphatidic acid (LPA)-induced increase of their interaction. Moreover, Rac1 activity was increased by both LPA and 8CPT-2Me-cAMP when treated with IOZ particles. Si-Vav2 impaired GTP-Rac1 levels in response to 8CPT-2Me-cAMP/IOZ. Phosphorylation of RhoA activates Rac1 in response to IOZ by the enhanced binding of phospho-RhoA to RhoGDI, leading to the release of Rac1 from the Rac1-RhoGDI complex. In conclusion, IOZ treatment induces Rap1 activation and phosphorylation of RhoA, which in turn cause Rac1 activation and promote Rac1 translocation to the membrane leading to binding with p22phox that activates NADPH oxidase and produces superoxide. [Copyright &y& Elsevier]
- Published
- 2012
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182. Sulfur mustard primes human neutrophils for increased degranulation and stimulates cytokine release via TRPM2/p38 MAPK signaling
- Author
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Ham, Hwa-Yong, Hong, Chang-Won, Lee, Si-Nae, Kwon, Min-Soo, Kim, Yeon-Ja, and Song, Dong-Keun
- Subjects
- *
MUSTARD gas , *NEUTROPHILS , *CYTOKINES , *TRP channels , *CELLULAR signal transduction , *IMMUNE response , *PHOSPHORYLATION , *DRUG receptors - Abstract
Abstract: Sulfur mustard (2,2′-bis-chloroethyl-sulfide; SM) has been a military threat since the World War I. The emerging threat of bioterrorism makes SM a major threat not only to military but also to civilian world. SM injury elicits an inflammatory response characterized by infiltration of neutrophils. Although SM was reported to prime neutrophils, the mechanism has not been identified yet. In the present study, we investigated the mechanism of SM-induced priming in human neutrophils. SM increased [Ca2+]i in human neutrophils in a concentration-dependent fashion. Transient receptor potential melastatin (TRPM) 2 inhibitors (clotrimazole, econazole and flufenamic acid) and silencing of TRPM2 by shRNA attenuated SM-induced [Ca2+]i increase. SM primed degranulation of azurophil and specific granules in response to activation by fMLP as previously reported. SB203580, an inhibitor of p38 MAPK, inhibited SM-induced priming. Neither PD98057, an ERK inhibitor, nor SP600215, a JNK inhibitor, inhibited SM-induced priming. In addition, SM enhanced phosphorylation of NF-kB p65 and release of TNF-α, interleukin (IL)-6 and IL-8. SB203580 inhibited SM-induced NF-kB phosphorylation and cytokine release. These results suggest the involvement of TRPM2/p38 MAPK pathway in SM-induced priming and cytokines release in neutrophils. [Copyright &y& Elsevier]
- Published
- 2012
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- View/download PDF
183. Efficient and stereoselective syntheses of DAB-1 and d-fagomine via chiral 1,3-oxazine
- Author
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Kim, Ji-Yeon, Mu, Yu, Jin, Xiangdan, Park, Seok-Hwi, Pham, Van-Thoai, Song, Dong-Keun, Lee, Kee-Young, and Ham, Won-Hun
- Subjects
- *
ORGANIC synthesis , *STEREOCHEMISTRY , *CHIRALITY , *IMINOSUGARS , *HETEROCYCLIC compounds , *HYDROGENATION , *PALLADIUM catalysts , *PYRROLIDINE , *RING formation (Chemistry) - Abstract
Abstract: The concise, stereocontrolled syntheses of DAB-1 and d-fagomine were achieved utilizing chiral oxazine. The key features in these strategies are the stereoselective intramolecular oxazine formation catalyzed by palladium(0), and pyrrolidine and piperidine formation by catalytic hydrogenation of oxazine. [Copyright &y& Elsevier]
- Published
- 2011
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184. Central or peripheral norepinephrine depletion enhances MK-801-induced plasma corticosterone level in mice
- Author
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Kim, Do-Hoon, Jung, Jun-Sub, Moon, Yoo-Sun, and Song, Dong-Keun
- Subjects
- *
NORADRENALINE , *ADRENOCORTICOTROPIC hormone , *CORTICOSTERONE , *INTERLEUKIN-6 , *CATECHOLAMINES , *LABORATORY mice , *ENZYME-linked immunosorbent assay , *CORTICOTROPIN releasing hormone - Abstract
Abstract: To investigate the involvement of central or peripheral catecholaminergic systems in the MK-801-induced increase in plasma corticosterone and interleukin-6 levels, we pretreated mice either intracerebroventricularly (i.c.v.) or intraperitoneally (i.p.) with 6-hydroxydopamine (6-OHDA) which depletes catecholamines. Pretreatment of animals with 6-OHDA (50 μg i.c.v. or 100 mg/kg i.p.) significantly enhanced the MK-801 (1 μg i.c.v.)-induced increase in plasma corticosterone level. On the other hand, pretreatment of mice with 6-OHDA (50 μg i.c.v. or 100 mg/kg i.p.) did not affect the MK-801 (1 μg i.c.v.)-induced increase in plasma IL-6 level. These results suggest that central and peripheral catecholaminergic systems are involved in the suppressive regulation of MK-801-induced plasma corticosterone level. [Copyright &y& Elsevier]
- Published
- 2009
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185. Inhibitory effects of long-term administration of ferulic acid on astrocyte activation induced by intracerebroventricular injection of β-amyloid peptide (1–42) in mice
- Author
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Cho, Jae-Young, Kim, Hee-Sung, Kim, Do-Hoon, Yan, Ji-Jing, Suh, Hong-Won, and Song, Dong-Keun
- Subjects
- *
NITRIC oxide , *PEPTIDES , *NITROGEN compounds , *CHEMOKINES - Abstract
Abstract: Accumulating evidence indicates that glial cells are actively involved in the pathogenesis of Alzheimer''s disease. We recently reported protective effects of long-term administration of ferulic acid against learning and memory deficit induced by centrally administered β-amyloid peptide (Aβ)1–42 in mice. In that report, we found that the Aβ1–42-induced increases in immunoreactivities of glial fibrillary acidic protein, the astrocyte marker, and interleukin(IL)-1β in the hippocampus are also suppressed by pretreatment with ferulic acid. In the present study, we aimed to further characterize the effect of long-term administration of ferulic acid on the centrally administered Aβ1–42-induced activation of glial cells in mice. Mice were allowed free access to drinking water (control) or water containing ferulic acid (0.006%) for 4 weeks, and then Aβ1–42 (410 pmol) was administered via intracerebroventricular injection. Intracerebroventricularly injected Aβ1–42 induced an increase in immunoreactivities of endothelial nitric oxide synthase (eNOS) and 3-nitrotyrosine (3-NT) in the activated astrocytes in the hippocampus. Pretreatment of ferulic acid for 4 weeks prevented the Aβ1–42-induced increase in eNOS and 3-NT immunoreactivities. Administration of ferulic acid per se induced a transient and slight increase in eNOS immunoreactivity in the hippocampus on day 14, which returned to basal levels on day 28. Intracerebroventricularly injected Aβ1–42 also increased interleukin-1α(IL-1α) immunoreactivity in the hippocampus, which was also suppressed by pretreatment with ferulic acid. These results demonstrate that long-term administration of ferulic acid induces suppression of the centrallly injected Aβ1–42-induced activation of astrocytes which is suggested to underlie the protective effect of ferulic acid against Aβ1–42 toxicity in vivo. [Copyright &y& Elsevier]
- Published
- 2005
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186. Effect of Zen Meditation on serum nitric oxide activity and lipid peroxidation
- Author
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Kim, Do-Hoon, Moon, Yoo-Sun, Kim, Hee-Sung, Jung, Jun-Sub, Park, Hyung-Moo, Suh, Hong-Won, Kim, Yung-Hi, and Song, Dong-Keun
- Subjects
- *
PEROXIDATION , *ZEN meditations , *NITRIC oxide , *STRESS management , *SERUM - Abstract
Abstract: This study was designed to investigate the effect of Zen Meditation on serum nitric oxide activity (NO) and oxidative stress (lipid peroxidation). The experimental group included 20 subjects who had practiced the Zen Meditation program in Meditation Center located in Seoul, South Korea. The control group included 20 subjects who did not practice any formal stress management technique and were age and sex matched with experimental group. To provide an assessment of nitric oxide production, the serum level of nitrate/nitrite was determined using the Griess reagent. Malondialdehyde (MDA) concentration was measured as a convenient index of lipid peroxidation by thiobarbituric acid (TBA) method. Meditation group showed a significant higher level of serum nitrate+nitrite concentration and a significant reduced level of serum malondialdehyde (MDA) than control group. A comprehensive randomized controlled trial should be performed to prove the causal relationship between meditation and level of nitric oxide or oxidative stress in reducing cardiovascular risk factors. [Copyright &y& Elsevier]
- Published
- 2005
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- View/download PDF
187. Therapeutic effects of lysophosphatidylcholine in experimental sepsis.
- Author
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Yan, Ji-Jing, Jung, Jun-Sub, Lee, Jung-Eun, Lee, Jongho, Huh, Sung-Oh, Kim, Hee-Sung, Jung, Kyeong Cheon, Cho, Jae-Young, Nam, Ju-Suk, Suh, Hong-Won, Kim, Yung-Hi, and Song, Dong-Keun
- Subjects
- *
LECITHIN , *SEPSIS vaccines , *ESCHERICHIA coli , *NEUTROPHIL immunology , *MICROBIAL toxins , *ENDOTOXINS , *THERAPEUTICS - Abstract
Sepsis represents a major cause of death in intensive care units. Here we show that administration of lysophosphatidylcholine (LPC), an endogenous lysophospholipid, protected mice against lethality after cecal ligation and puncture (CLP) or intraperitoneal injection of Escherichia coli. In vivo treatment with LPC markedly enhanced clearance of intraperitoneal bacteria and blocked CLP-induced deactivation of neutrophils. In vitro, LPC increased bactericidal activity of neutrophils, but not macrophages, by enhancing H2O2 production in neutrophils that ingested E. coli. Incubation with an antibody to the LPC receptor, G2A, inhibited LPC-induced protection from CLP lethality and inhibited the effects of LPC in neutrophils. G2A-specific antibody also blocked the inhibitory effects of LPC on certain actions of lipopolysaccharides (LPS), including lethality and the release of tumor necrosis factor-a (TNF-a) from neutrophils. These results suggest that LPC can effectively prevent and treat sepsis and microbial infections. [ABSTRACT FROM AUTHOR]
- Published
- 2004
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- View/download PDF
188. Protection against β-amyloid peptide-induced memory impairment with long-term administration of extract of Angelica gigas or decursinol in mice
- Author
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Yan, Ji-Jing, Kim, Do-Hoon, Moon, Yoo-Sun, Jung, Jun-Sub, Ahn, Eun-Mi, Baek, Nam-In, and Song, Dong-Keun
- Subjects
- *
AMYLOID , *PEPTIDES , *MICE , *PROTEINS - Abstract
We investigated the effect of long-term oral administration of ethanolic extract of Angelica gigas Nakai (Umbelliferae) (EAG) or decursinol, a coumarin isolated from A. gigas, on β-amyloid peptide 1–42 (Aβ1–42)-induced memory impairment in mice. Mice were allowed free access to drinking water (control) or water containing different concentrations of EAG. After 4 weeks, Aβ1–42 (410 pmol) was administered via intracerebroventricular injection. Pretreatment of mice with EAG (0.1%) for 4 weeks significantly blocked the Aβ1–42-induced impairment in passive avoidance performance. Next, mice were fed with chow mixed with various doses of decursinol for 4 weeks before intracerebroventricular injection of Aβ1–42 (410 pmol). Pretreatment of mice with decursinol (0.001%, 0.002%, and 0.004%) for 4 weeks significantly attenuated the Aβ1–42-induced impairment in passive avoidance performance. Decursinol (0.004%) also significantly blunted the Aβ1–42-induced decrease in alternation behavior (spatial working memory) in the Y-maze test without change in general locomotor activity. These findings suggest that EAG or decursinol may have preventive effect against memory impairment related with Aβ of Alzheimer''s disease. [Copyright &y& Elsevier]
- Published
- 2004
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189. Impaired water maze learning performance in μ-opioid receptor knockout mice
- Author
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Jang, Choon-Gon, Lee, Seok-Yong, Yoo, Ji-Hoon, Yan, Ji-Jing, Song, Dong-Keun, Loh, Horace H., and Ho, Ing K.
- Subjects
- *
HIPPOCAMPUS (Brain) , *DENTATE gyrus , *LEARNING , *VICTORIA amazonica - Abstract
Previous study has demonstrated that the lack of μ-opioid receptor decreased LTP in the dentate gyrus of the hippocampus, suggesting the possibility that the lack of μ-opioid receptor may accompany a change in learning and memory. However, no behavioral study has been undertaken to correlate LTP deficits with spatial memory impairment in μ-opioid receptor knockout mice. Therefore, the present study investigated the hypothesis that μ-opioid receptors contribute to learning and memory by using the Morris water maze, and comparing responses in wild type and μ-opioid receptor gene knockout mice. Our results indicated that μ-opioid receptor knockout mice showed a significant spatial memory impairment compared to wild type in the Morris water maze. This result suggests that the expression of μ-opioid receptor plays an important role in spatial learning and memory examined by Morris water maze. [Copyright &y& Elsevier]
- Published
- 2003
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190. Route-dependent effects of the non-NMDA receptor antagonist CNQX on plasma corticosterone levels in mice
- Author
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Kim, Do-Hoon, Moon, Yoo-Sun, Jung, Jun-Sub, Suh, Hong-Won, and Song, Dong-Keun
- Subjects
- *
METHYL aspartate , *CORTICOTROPIN releasing hormone , *CORTICOSTERONE , *MOVEMENT disorders , *DIAGNOSIS - Abstract
A non-N-methyl-d-aspartate (non-NMDA) receptor antagonist, 6-cyano-7-nitro-quinoxaline-2,3-dione (CNQX), administered intracerebroventricularly (0.1–0.5 μg), significantly inhibited the immobilization stress-induced plasma corticosterone levels in a dose-dependent manner. However, CNQX administered intraperitoneally (1–10 mg/kg) showed a dose-dependent increase of basal plasma corticosterone levels in nonstressed mice and an additive increase of plasma corticosterone levels at the dose of 10 mg/kg in 1 h immobilization-stressed mice. The results suggest that the central and peripheral non-NMDA receptors may be differently involved in the regulation of plasma corticosterone levels in non- and immobilization-stressed mice. [Copyright &y& Elsevier]
- Published
- 2003
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191. Transparent and visible light-activated antimicrobial air filters from electrospun crystal violet-embedded polyacrylonitrile nanofibers.
- Author
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Lee SY, Shin JH, Kim IH, Choi DY, Lee DU, Hwang GB, Han B, Kim SB, Song DK, Park I, and Jung JH
- Subjects
- Staphylococcus epidermidis drug effects, Anti-Infective Agents pharmacology, Anti-Infective Agents chemistry, Nanofibers chemistry, Acrylic Resins chemistry, Air Filters, Gentian Violet, Light
- Abstract
Bioaerosols pose significant risks to indoor environments and public health, driving interest in advanced antimicrobial air filtration technologies. Conventional antimicrobial filters often suffer from diminished efficacy over time and require additional binders to retain antimicrobial agents. This study introduces CV@PAN, a self-disinfecting nanofiber fabricated via electrospinning of crystal violet (CV) and polyacrylonitrile (PAN). The process effectively incorporated CV into the PAN framework, minimizing environmental release. We comprehensively analyzed the physical and chemical properties of CV@PAN nanofibers, including fiber morphology, size distribution, chemical composition, thermal stability, and transparency. The CV@PAN nanofibers exhibited an average diameter of 0.28 μm. The fabricated filter achieved a bioaerosol removal efficiency of >99.2% against Staphylococcus epidermidis, with a low-pressure drop of 401.6 Pa at a face velocity of 16 cm/s. The filter demonstrated an optical transparency exceeding 50%. Upon visible light exposure, the embedded CV generated reactive oxygen species, resulting in an antibacterial efficacy of >99.9%. These findings demonstrate the significant potential of CV@PAN nanofiber filters for air quality management and their promise as an advancement in antibacterial air filtration technology., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)
- Published
- 2025
- Full Text
- View/download PDF
192. Therapeutic effects of mirodenafil, a phosphodiesterase 5 inhibitor, on stroke models in rats.
- Author
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Kim F, Singh P, Jo H, Xi T, Song DK, Ku SK, and Choung JJ
- Subjects
- Animals, Male, Rats, Stroke drug therapy, Pyrimidinones pharmacology, Pyrimidinones therapeutic use, Infarction, Middle Cerebral Artery drug therapy, Dose-Response Relationship, Drug, Phosphodiesterase 5 Inhibitors pharmacology, Phosphodiesterase 5 Inhibitors therapeutic use, Rats, Sprague-Dawley, Disease Models, Animal, Sulfonamides pharmacology, Sulfonamides therapeutic use
- Abstract
Mirodenafil is a phosphodiesterase 5 (PDE5) inhibitor with high specificity for its target and good blood-brain barrier permeability. The drug, which is currently used for treatment of erectile dysfunction, reduces Aβ and pTau levels and improves cognitive function in mouse models of Alzheimer's disease. In the present study, we investigated the effect of mirodenafil in the transient and permanent middle cerebral artery occlusion (tMCAO and pMCAO) models of stroke in rats. Starting 24 h after cerebral artery occlusion, mirodenafil was administered subcutaneously at doses of 0.5, 1, and 2 mg/kg per day for 9 days in the tMCAO model and for 28 days in the pMCAO model. Mirodenafil significantly increased sensorimotor and cognitive recovery of tMCAO and pMCAO rats compared to saline control rats, and significantly decreased the amount of degenerative cells and cleaved caspase-3 and cleaved PARP immunoreactive cells. Effects were seen in a dose-dependent manner up to 1 mg/kg mirodenafil. The benefits of mirodenafil treatment increased with longer treatment duration, and the largest improvements over control were typically observed on the last assessment day. There was no effect of mirodenafil on infarct volume in both tMCAO and pMCAO rats. In an experiment to determine the treatment window for mirodenafil effects, a protective effect was observed when treatment was delayed 72 h after MCAO, although the most improvement was observed with shorter treatment windows. Using pMCAO and tMCAO rat models of stroke, we determined that mirodenafil improves the recovery of sensorimotor and cognitive functions after MCAO and protects cortical cells from apoptosis and degeneration. Greater benefit was observed with longer duration of treatment, and improvement was seen even when treatment was delayed., Competing Interests: Declaration of competing interest The authors declare no competing interests., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2025
- Full Text
- View/download PDF
193. Vibrotactile stimulation at 40 Hz inhibits Aβ-induced changes in SH-SY5Y, BV2 cells, and pericytes.
- Author
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Shin CH, Kang BW, Cho MW, Ha JY, Choung JJ, Song DK, Ko HK, Nam MH, and Seo YK
- Subjects
- Humans, Cell Line, Tumor, tau Proteins metabolism, Calcium metabolism, Alzheimer Disease therapy, Alzheimer Disease metabolism, Autophagy physiology, Brain metabolism, Amyloid beta-Peptides metabolism, Vibration, Pericytes metabolism, Cell Survival physiology, Microglia metabolism
- Abstract
Alzheimer's disease (AD) poses a major societal challenge, yet no definitive cure exists. Noninvasive brain stimulation methods, such as transcranial magnetic stimulation and transcranial direct current stimulation, have shown promise in alleviating cognitive symptoms associated with neurodegenerative disorders. This study investigated the effects of 40 Hz vibrotactile stimulation on AD-related cellular responses using SH-SY5Y neuroblastoma cells, primary human brain pericytes, and BV2 microglia. SH-SY5Y cells and brain pericytes treated with oligomeric beta-amyloid (Aβ) underwent 40 Hz vibrational stimulation for varying durations. Cell viability was determined via the CCK-8 assay, while intracellular calcium levels in pericytes were assessed. Protein expression was measured using western blotting, and gene expression was quantified via a real-time quantitative polymerase chain reaction. Detailed vibrational parameters were employed to ensure precise stimulation. Notably, 40 Hz vibrotactile stimulation improved cell viability in Aβ-exposed SH-SY5Y cells, reduced intracellular calcium ion (Ca2+) levels in Aβ-treated pericytes, activated autophagy, and mitigated tau hyperphosphorylation in SH-SY5Y cells. Additionally, it exhibited anti-neuroinflammatory properties in BV2 microglia. These findings highlight the potential of 40 Hz vibrotactile stimulation as a therapeutic strategy for AD., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)
- Published
- 2025
- Full Text
- View/download PDF
194. Polypharmacological Potential of Phosphodiesterase 5 Inhibitors for the Treatment of Neurocognitive Disorders.
- Author
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Kumar A, Kim F, Song DK, and Choung JJ
- Subjects
- Humans, Neurocognitive Disorders drug therapy, Animals, Alzheimer Disease drug therapy, Phosphodiesterase 5 Inhibitors pharmacology, Phosphodiesterase 5 Inhibitors therapeutic use
- Abstract
The prevalence of neurocognitive disorders (NCD) increases every year as the population continues to age, leading to significant global health concerns. Overcoming this challenge requires identifying biomarkers, risk factors, and effective therapeutic interventions that might provide meaningful clinical benefits. For Alzheimer's disease (AD), one of the most studied NCD, approved drugs include acetylcholinesterase inhibitors (rivastigmine, donepezil, and galantamine), an NMDA receptor antagonist (memantine), and anti-amyloid monoclonal antibodies (aducanumab and lecanemab). These drugs offer limited relief, targeting singular pathological processes of the AD. Given the multifactorial nature of the NCDs, a poly-pharmacological strategy may lead to improved outcomes compared to the current standard of care. In this regard, phosphodiesterase 5 (PDE5) inhibitors emerged as promising drug candidates for the treatment of neurocognitive disorders. These inhibitors increase cGMP levels and CREB signaling, thus enhancing learning, memory and neuroprotection, while reducing Aβ deposition, tau phosphorylation, oxidative stress, and neuroinflammation. In the present article, we evaluate the therapeutic potential of different PDE5 inhibitors to outline their multifaceted impact in the NCDs.
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- 2024
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195. Protective Effects of Sesame Glycoproteins on Ultraviolet-Induced Skin Aging: In Vitro and In Vivo Studies.
- Author
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Baik KK, Song WY, Song DK, Yun J, Jang JH, Oh JY, Lee MJ, Go E, Lee KJ, Roh E, and Kim JE
- Abstract
Background/objectives: Ultraviolet (UV) radiation is a primary factor in skin photoaging, leading to wrinkles, reduced elasticity, and pigmentation changes due to damage to cellular DNA, proteins, and lipids. Glycoproteins from sesame cake (SPE) have potential protective effects against UV-induced skin aging. This study investigated the anti-photoaging effects of SPE on UV-induced damage in human keratinocyte HaCaT cells and SKH-1 hairless mice., Methods: SPE was evaluated for its ability to mitigate UV-induced damage in HaCaT cells by assessing MMP-1 protein and mRNA expression levels, as well as the activity of transcription factors AP-1 and NF-κB. The phosphorylation of AKT and MAPK pathways was also analyzed. In vivo, SKH-1 hairless mice were exposed to UV radiation, and the effects of SPE on wrinkle formation and skin structure were assessed by measuring wrinkle length, area, and volume., Results: SPE significantly inhibited UV-induced MMP-1 protein and mRNA expression in HaCaT cells, indicating suppression of AP-1 and NF-κB transcription factors involved in MMP-1 production. Additionally, SPE reduced UV-induced phosphorylation of AKT and MAPK pathways. In SKH-1 hairless mice, SPE treatment led to significant reductions in wrinkle length, area, and volume, preserving skin structure in UV-exposed mice., Conclusions: The findings demonstrate that SPE has protective effects against UV-induced photoaging by inhibiting key molecular pathways associated with skin aging. SPE shows promise as a natural anti-photoaging agent, providing a foundation for future skincare product development. Further studies are warranted to explore the molecular mechanisms in detail and to validate these effects through clinical trials.
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- 2024
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196. Diabetes Primes Neutrophils for Neutrophil Extracellular Trap Formation through Trained Immunity.
- Author
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Shrestha S, Lee YB, Lee H, Choi YK, Park BY, Kim MJ, Youn YJ, Kim SH, Jung SJ, Song DK, Jin HK, Bae JS, Lee IK, Jeon JH, and Hong CW
- Abstract
Neutrophils are primed for neutrophil extracellular trap (NET) formation during diabetes, and excessive NET formation from primed neutrophils compromises wound healing in patients with diabetes. Here, we demonstrate that trained immunity mediates diabetes-induced NET priming in neutrophils. Under diabetic conditions, neutrophils exhibit robust metabolic reprogramming comprising enhanced glycolysis via the pentose phosphate pathway and fatty acid oxidation, which result in the accumulation of acetyl-coenzyme A. Adenosine 5'-triphosphate-citrate lyase-mediated accumulation of acetyl-coenzyme A and histone acetyltransferases further induce the acetylation of lysine residues on histone 3 (AcH3K9, AcH3K14, and AcH3K27) and histone 4 (AcH4K8). The pharmacological inhibition of adenosine 5'-triphosphate-citrate lyase and histone acetyltransferases completely inhibited high-glucose-induced NET priming. The trained immunity of neutrophils was further confirmed in neutrophils isolated from patients with diabetes. Our findings suggest that trained immunity mediates functional changes in neutrophils in diabetic environments, and targeting neutrophil-trained immunity may be a potential therapeutic target for controlling inflammatory complications of diabetes., Competing Interests: Competing interests: The authors declare that they have no competing interests., (Copyright © 2024 Sanjeeb Shrestha et al.)
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- 2024
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197. Retraction Note: Lysophosphatidylcholine induces adenosine release from macrophages via TRPM7-mediated mitochondrial activation.
- Author
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Youssef AM and Song DK
- Published
- 2023
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- View/download PDF
198. Venadaparib Is a Novel and Selective PARP Inhibitor with Improved Physicochemical Properties, Efficacy, and Safety.
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Lee M, Je IG, Kim JE, Yoo Y, Lim JH, Jang E, Lee Y, Song DK, Moon AN, Kim JA, Jeong J, Park JT, Lee JW, Yang JH, Hong CH, Park SY, Park YW, Baek NS, Lee S, Ha KS, Choi S, and Lee WS
- Subjects
- Male, Humans, Cell Line, Tumor, Homologous Recombination, Poly(ADP-ribose) Polymerase Inhibitors pharmacology, Poly(ADP-ribose) Polymerase Inhibitors therapeutic use, Antineoplastic Agents pharmacology, Antineoplastic Agents therapeutic use
- Abstract
PARP inhibitors have been approved by the FDA for use in the treatment of patients with ovarian, breast, pancreatic, and prostate cancers. PARP inhibitors show diverse suppressive effects on PARP family members and PARP-DNA trapping potency. These properties are associated with distinct safety/efficacy profiles. Here, we report the nonclinical characteristics of venadaparib (also known as IDX-1197 or NOV140101), a novel potent PARP inhibitor. The physiochemical properties of venadaparib were analyzed. Furthermore, the efficacy of venadaparib against PARP enzymes, PAR formation, and PARP trapping activities, and growth inhibition of cell lines with BRCA mutations were evaluated. Ex vivo and in vivo models were also established to study pharmacokinetics/pharmacodynamics, efficacy, and toxicity. Venadaparib specifically inhibits PARP-1 and -2 enzymes. Oral administration of venadaparib HCl at doses above 12.5 mg/kg significantly reduced tumor growth in the OV_065 patient-derived xenograft model. Intratumoral PARP inhibition remained at over 90% until 24 hours after dosing. Venadaparib had wider safety margins than olaparib. Notably, venadaparib showed favorable physicochemical properties and superior anticancer effects in homologous recombination-deficient in vitro and in vivo models with improved safety profiles. Our results suggest the possibility of venadaparib as a next-generation PARP inhibitor. On the basis of these findings, phase Ib/IIa studies on the efficacy and safety of venadaparib have been initiated., (©2023 The Authors; Published by the American Association for Cancer Research.)
- Published
- 2023
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199. Lysophosphatidylcholine induces adenosine release from macrophages via TRPM7-mediated mitochondrial activation.
- Author
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Youssef AM and Song DK
- Subjects
- Adenosine Triphosphate, Cyclic AMP-Dependent Protein Kinases, Hypoxia, Magnesium, Netrin-1, Protein Serine-Threonine Kinases, Adenosine metabolism, Lysophosphatidylcholines pharmacology, Macrophages metabolism, TRPM Cation Channels
- Abstract
Even though macrophages have the potential to harm tissues through excessive release of inflammatory mediators, they play protective roles to maintain tissue integrity. In this study, we hypothesized that lysophosphatidylcholine (LPC), via G2A and A
2B receptors, puts brakes on macrophages by the induction of adenosine release which could contribute to termination of inflammation. Mechanistically, LPC-induced PGE2 production followed by the activation of cAMP/protein kinase A (PKA) pathway which results in the activation of LKB1/AMPK signaling pathway leading to increasing Mg2+ influx concomitantly with an increase in mitochondrial membrane potential (MMP, Δψm ) and ATP production. Then, ATP is converted to adenosine intracellularly followed by efflux via ENT1. In a parallel pathway, LPC-induced elevation of cytosolic calcium was essential for adenosine release, and Ca2+ /calmodulin signaling cooperated with PKA to regulate ENT1 permeation to adenosine. Pharmacological blockade of TRPM7 and antisense treatment suppressed LPC-induced adenosine release and magnesium influx in bone marrow-derived macrophages (BMDMs). Moreover, LPC suppressed LPS-induced phosphorylation of connexin-43, which may counteract TLR4-mediated inflammatory response. Intriguingly, we found LPC increased netrin-1 production from BMDMs. Netrin-1 induces anti-inflammatory signaling via A2B receptor. In the presence of adenosine deaminase which removes adenosine in the medium, the chemotaxis of macrophages toward LPC was significantly increased. Hypoxia and metabolic acidosis are usually developed in a variety of inflammatory situations such as sepsis. We found LPC augmented hypoxia- or acidosis-induced adenosine release from BMDMs. These results provide evidence of LPC-induced brake-like action on macrophages by adenosine release via cellular magnesium signaling., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)- Published
- 2022
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200. Glycine induces enhancement of bactericidal activity of neutrophils.
- Author
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Kang SH, Ham HY, Hong CW, and Song DK
- Abstract
Severe bacterial infections are frequently accompanied by depressed neutrophil functions. Thus, agents that increase the microbicidal activity of neutrophils could add to a direct antimicrobial therapy. Lysophosphatidylcholine augments neutrophil bactericidal activity via the glycine (Gly)/glycine receptor (GlyR) α2/TRPM2/p38 mitogen-activated protein kinase (MAPK) pathway. However, the direct effect of glycine on neutrophil bactericidal activity was not reported. In this study, the effect of glycine on neutrophil bactericidal activity was examined. Glycine augmented bactericidal activity of human neutrophils (EC
50 = 238 μM) in a strychnine (a GlyR antagonist)-sensitive manner. Glycine augmented bacterial clearance in mice, which was also blocked by strychnine (0.4 mg/kg, s.c.). Glycine enhanced NADPH oxidase-mediated reactive oxygen species (ROS) production and TRPM2-mediated [Ca2+ ]i increase in neutrophils that had taken up E. coli . Glycine augmented Lucifer yellow uptake (fluid-phase pinocytosis) and azurophil granule-phagosome fusion in neutrophils that had taken up E. coli in an SB203580 (a p38 MAPK inhibitor)-sensitive manner. These findings indicate that glycine augments neutrophil microbicidal activity by enhancing azurophil granule-phagosome fusion via the GlyRα2/ROS/calcium/p38 MAPK pathway. We suggest that glycine could be a useful agent for increasing neutrophil bacterial clearance.- Published
- 2022
- Full Text
- View/download PDF
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