34 results on '"Eun Kyung Yoo"'
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2. Pyruvate Dehydrogenase Kinase Is a Metabolic Checkpoint for Polarization of Macrophages to the M1 Phenotype
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Byong-Keol Min, Sungmi Park, Hyeon-Ji Kang, Dong Wook Kim, Hye Jin Ham, Chae-Myeong Ha, Byung-Jun Choi, Jung Yi Lee, Chang Joo Oh, Eun Kyung Yoo, Hui Eon Kim, Byung-Gyu Kim, Jae-Han Jeon, Do Young Hyeon, Daehee Hwang, Yong-Hoon Kim, Chul-Ho Lee, Taeho Lee, Jung-whan Kim, Yeon-Kyung Choi, Keun-Gyu Park, Ajay Chawla, Jongsoon Lee, Robert A. Harris, and In-Kyu Lee
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dichloroacetate ,high-fat diet ,inflammation ,insulin resistance ,macrophage polarization ,metabolic reprogramming ,Immunologic diseases. Allergy ,RC581-607 - Abstract
Metabolic reprogramming during macrophage polarization supports the effector functions of these cells in health and disease. Here, we demonstrate that pyruvate dehydrogenase kinase (PDK), which inhibits the pyruvate dehydrogenase-mediated conversion of cytosolic pyruvate to mitochondrial acetyl-CoA, functions as a metabolic checkpoint in M1 macrophages. Polarization was not prevented by PDK2 or PDK4 deletion but was fully prevented by the combined deletion of PDK2 and PDK4; this lack of polarization was correlated with improved mitochondrial respiration and rewiring of metabolic breaks that are characterized by increased glycolytic intermediates and reduced metabolites in the TCA cycle. Genetic deletion or pharmacological inhibition of PDK2/4 prevents polarization of macrophages to the M1 phenotype in response to inflammatory stimuli (lipopolysaccharide plus IFN-γ). Transplantation of PDK2/4-deficient bone marrow into irradiated wild-type mice to produce mice with PDK2/4-deficient myeloid cells prevented M1 polarization, reduced obesity-associated insulin resistance, and ameliorated adipose tissue inflammation. A novel, pharmacological PDK inhibitor, KPLH1130, improved high-fat diet-induced insulin resistance; this was correlated with a reduction in the levels of pro-inflammatory markers and improved mitochondrial function. These studies identify PDK2/4 as a metabolic checkpoint for M1 phenotype polarization of macrophages, which could potentially be exploited as a novel therapeutic target for obesity-associated metabolic disorders and other inflammatory conditions.
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- 2019
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3. Identification of Selective ERRγ Inverse Agonists
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Jina Kim, Chun Young Im, Eun Kyung Yoo, Min Jung Ma, Sang-Bum Kim, Eunmi Hong, Jungwook Chin, Hayoung Hwang, Sungwoo Lee, Nam Doo Kim, Jae-Han Jeon, In-Kyu Lee, Yong Hyun Jeon, Hueng-Sik Choi, Seong Heon Kim, and Sung Jin Cho
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estrogen-related receptor gamma ,inverse agonist ,ADMET ,GSK5182 ,Organic chemistry ,QD241-441 - Abstract
GSK5182 (4) is currently one of the lead compounds for the development of estrogen-related receptor gamma (ERRγ) inverse agonists. Here, we report the design, synthesis, pharmacological and in vitro absorption, distribution, metabolism, excretion, toxicity (ADMET) properties of a series of compounds related to 4. Starting from 4, a series of analogs were structurally modified and their ERRγ inverse agonist activity was measured. A key pharmacophore feature of this novel class of ligands is the introduction of a heterocyclic group for A-ring substitution in the core scaffold. Among the tested compounds, several of them are potent ERRγ inverse agonists as determined by binding and functional assays. The most promising compound, 15g, had excellent binding selectivity over related subtypes (IC50 = 0.44, >10, >10, and 10 μM at the ERRγ, ERRα, ERRβ, and ERα subtypes, respectively). Compound 15g also resulted in 95% transcriptional repression at a concentration of 10 μM, while still maintaining an acceptable in vitro ADMET profile. This novel class of ERRγ inverse agonists shows promise in the development of drugs targeting ERRγ-related diseases.
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- 2016
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4. Design, Synthesis, and Biological Evaluation of New Peripheral 5HT2A Antagonists for Nonalcoholic Fatty Liver Disease
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Won Gun Choi, Jin Sook Song, Hail Kim, Dooseop Kim, Jin Hee Ahn, Myung Ae Bae, Wonsuk Choi, Heejong Lee, Minhee Kim, Jae-Han Jeon, Inkyu Lee, Haushabhau S. Pagire, Inseon Hwang, Eun Kyung Yoo, Jihyeon Yoon, Seung Mi Lee, Won Mi Lee, Eun Young Lee, Mi Jin Kim, and Suvarna H. Pagire
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biology ,Chemistry ,hERG ,Pimavanserin ,Pharmacology ,medicine.disease ,Energy homeostasis ,chemistry.chemical_compound ,In vivo ,Drug Discovery ,Nonalcoholic fatty liver disease ,Knockout mouse ,medicine ,biology.protein ,Molecular Medicine ,Steatosis ,5-HT receptor - Abstract
Nonalcoholic fatty liver disease (NAFLD) is increasingly prevalent worldwide, causing serious liver complications, including nonalcoholic steatohepatitis. Recent findings suggest that peripheral serotonin (5-hydroxytryptamine, 5HT) regulates energy homeostasis, including hepatic lipid metabolism. More specifically, liver-specific 5HT2A knockout mice exhibit alleviated hepatic lipid accumulation and hepatic steatosis. Here, structural modifications of pimavanserin (CNS drug), a 5HT2A antagonist approved for Parkinson's disease, led us to synthesize new peripherally acting 5HT2A antagonists. Among the synthesized compounds, compound 14a showed good in vitro activity, good liver microsomal stability, 5HT subtype selectivity, and no significant inhibition of CYP and hERG. The in vitro and in vivo blood-brain barrier permeability study proved that 14a acts peripherally. Compound 14a decreased the liver weight and hepatic lipid accumulation in high-fat-diet-induced obesity mice. Our study suggests new therapeutic possibilities for peripheral 5HT2A antagonists in NAFLD.
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- 2020
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5. Therapeutic effect of dichloroacetate against atherosclerosis via hepatic FGF21 induction mediated by acute AMPK activation
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Chul-Ho Lee, Dong Wook Kim, Hyeon-Ji Kang, Jae-Han Jeon, Bo-Yoon Park, Jeong Eun Kim, Hui Eon Kim, Yong-Hoon Kim, Sungmi Park, Chang Joo Oh, Inkyu Lee, Byong-Keol Min, Ji Min Lee, Eun Kyung Yoo, Yong Hyun Jeon, Mi Jin Kim, and Younghoon Go
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Male ,0301 basic medicine ,FGF21 ,Mice, Knockout, ApoE ,medicine.medical_treatment ,Clinical Biochemistry ,Adipose tissue ,lcsh:Medicine ,AMP-Activated Protein Kinases ,Biochemistry ,Mice ,0302 clinical medicine ,Adipose Tissue, Brown ,Hyperlipidemia ,Brown adipose tissue ,lcsh:QD415-436 ,Enzyme Inhibitors ,Uncoupling Protein 1 ,Chemistry ,Plaque, Atherosclerotic ,Mitochondria ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Heat generation ,Molecular Medicine ,Signal Transduction ,medicine.medical_specialty ,Pyruvate dehydrogenase kinase ,Iodide Peroxidase ,Article ,lcsh:Biochemistry ,03 medical and health sciences ,Apolipoproteins E ,Oxygen Consumption ,Internal medicine ,medicine ,Animals ,PPAR alpha ,Obesity ,RNA, Messenger ,Molecular Biology ,Dyslipidaemias ,Dyslipidemias ,Dichloroacetic Acid ,Insulin ,lcsh:R ,Pyruvate Dehydrogenase Acetyl-Transferring Kinase ,AMPK ,Cardiovascular Agents ,Atherosclerosis ,medicine.disease ,Fibroblast Growth Factors ,Mice, Inbred C57BL ,030104 developmental biology ,Endocrinology ,Gene Expression Regulation ,Diet, Western ,Energy Metabolism - Abstract
Dyslipidemia-induced atherosclerosis, which has a risk of high morbidity and mortality, can be alleviated by metabolic activation associated with mitochondrial function. The effect of dichloroacetate (DCA), a general pyruvate dehydrogenase kinase (PDK) inhibitor, on in vivo energy expenditure in ApoE−/− mice fed a western diet (WD) has not yet been investigated. WD-fed ApoE−/− mice developed atherosclerotic plaques and hyperlipidemia along with obesity, which were significantly ameliorated by DCA administration. Increased oxygen consumption was associated with heat production in the DCA-treated group, with no change in food intake or physical activity compared with those of the control. These processes were correlated with the increased gene expression of Dio2 and Ucp-1, which represents brown adipose tissue (BAT) activation, in both WD-induced atherosclerosis and high-fat-induced obesity models. In addition, we found that DCA stimulated hepatic fibroblast growth factor 21 (Fgf21) mRNA expression, which might be important for lowering lipid levels and insulin sensitization via BAT activation, in a dose- and time-dependent manner associated with serum FGF21 levels. Interestingly, Fgf21 mRNA expression was mediated in an AMP-activated protein kinase (AMPK)-dependent manner within several minutes after DCA treatment independent of peroxisome proliferator-activated receptor alpha (PPARα). Taken together, the results suggest that enhanced glucose oxidation by DCA protects against atherosclerosis by inducing hepatic FGF21 expression and BAT activation, resulting in augmented energy expenditure for heat generation., Atherosclerosis: Expending surplus energy on cardiovascular health A compound that shifts cellular energy consumption into inflation confers effective protection against cardiovascular diseases. Elevated lipid put people at risk of atherosclerosis and coronary artery disease, but new findings from researchers led by In-Kyu Lee at Kyungpook National University in Daegu, South Korea reveal a potential strategy for preventing such accumulation. They have demonstrated that a small molecule called dichloroacetate targeting for mitochondrial respiration boosts metabolic activity and impedes atherosclerosis progression in a experimental animal model fed Western diets. Dichloroacetate might work by stimulating signals that activate brown adipose tissue, a type of fat that burns excess nutrients for energy rather than storing them. These signaling pathways have been linked to other aspects of obesity and cardiovascular disease, suggesting dichloroacetate may be a promising drug candidate.
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- 2019
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6. Identification of Novel Resorcinol Amide Derivatives as Potent and Specific Pyruvate Dehydrogenase Kinase (PDHK) Inhibitors
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Sungmi Park, Inkyu Lee, Injae Shin, Nam Doo Kim, Mi Jin Kim, Taebo Sim, Eun Kyung Yoo, Hojong Yoon, Kyungseon Cho, and Hanna Cho
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Pyruvate dehydrogenase kinase ,Apoptosis ,Molecular Dynamics Simulation ,medicine.disease_cause ,01 natural sciences ,Inhibitory Concentration 50 ,03 medical and health sciences ,Cell Line, Tumor ,Neoplasms ,Drug Discovery ,Cell Adhesion ,medicine ,Humans ,Enzyme Inhibitors ,Phosphorylation ,Cell Proliferation ,030304 developmental biology ,0303 health sciences ,Cell growth ,Kinase ,Chemistry ,Pyruvate Dehydrogenase Acetyl-Transferring Kinase ,Resorcinols ,Pyruvate dehydrogenase complex ,Amides ,0104 chemical sciences ,Molecular Docking Simulation ,010404 medicinal & biomolecular chemistry ,Biochemistry ,Cell culture ,Cancer cell ,Molecular Medicine ,Peptides ,Reactive Oxygen Species ,Carcinogenesis ,Hydrophobic and Hydrophilic Interactions - Abstract
Pyruvate dehydrogenase kinases (PDHKs) promote abnormal respiration in cancer cells. Studies with novel resorcinol amide derivatives based on VER-246608 (6) led to the identification of 19n and 19t containing five-membered heteroaromatic rings as unique structural features. These substances possess single-digit nanomolar activities against PDHKs. 19t exhibits higher potencies against PDHK1/2/4 than does 6 and inhibits only PDHKs among 366 kinases. Moreover, 19g, 19l, and 19s were found to be isotype-selective PDHK inhibitors. Molecular dynamics simulations provide a better understanding of how the heteroaromatic rings affect the activities of 19n and 19t on PDHK1/2/3/4. Moreover, 19n possesses a much higher antiproliferative activity against cancer cells than does 6. We demonstrated that the results of PDH assays better correlate with cellular activities than do those of PDHK kinase assays. Furthermore, 19n induces apoptosis of cancer cells via mitochondrial dysfunction, suppresses tumorigenesis, and displays a synergistic effect on satraplatin suppression of cancer cell proliferation.
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- 2019
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7. Discovery of Novel Pyruvate Dehydrogenase Kinase 4 Inhibitors for Potential Oral Treatment of Metabolic Diseases
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Mahesh Dighe, Jin Hee Ahn, Myung Ae Bae, Haushabhau S. Pagire, Eun Jung Bae, Sungmi Park, Kwan-Young Jung, Hee Eon Gim, Seungmi Lee, Tae-Ho Lee, Suvarna H. Pagire, Kwang-Hyeon Liu, Young In Chi, Ga-Hyun Lee, Kyu Myung Lee, Jin Sook Song, Ashok Kumar Jaladi, Minhee Kim, Yong Hyun Jeon, Jae-Han Jeon, Eun Kyung Yoo, Inkyu Lee, Dahye Lee, Won-Il Choi, and Yoon Kyung Jang
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Male ,Allosteric regulation ,Administration, Oral ,Mice, Obese ,PDK4 ,Anthraquinones ,Pharmacology ,Cell Line ,Mice ,Structure-Activity Relationship ,Insulin resistance ,Metabolic Diseases ,Drug Discovery ,medicine ,Animals ,Humans ,Hypoglycemic Agents ,Structure–activity relationship ,Obesity ,Protein Kinase Inhibitors ,Binding Sites ,Cell growth ,Chemistry ,medicine.disease ,In vitro ,Rats ,Mice, Inbred C57BL ,Molecular Docking Simulation ,Drug development ,Microsomes, Liver ,Molecular Medicine ,Protein Kinases ,Lipoamide binding ,Half-Life - Abstract
Pyruvate dehydrogenase kinase 4 (PDK4) activation is associated with metabolic diseases including hyperglycemia, insulin resistance, allergies, and cancer. Structural modifications of hit anthraquinone led to the identification of a new series of allosteric PDK4 inhibitors. Among this series, compound 8c showed promising in vitro activity with an IC50 value of 84 nM. Good metabolic stability, pharmacokinetic profiles, and possible metabolites were suggested. Compound 8c improved glucose tolerance in diet-induced obese mice and ameliorated allergic reactions in a passive cutaneous anaphylaxis mouse model. Additionally, compound 8c exhibited anticancer activity by controlling cell proliferation, transformation, and apoptosis. From the molecular docking studies, compound 8c displayed optimal fitting in the lipoamide binding site (allosteric) with a full fitness, providing a new scaffold for drug development toward PDK4 inhibitors.
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- 2019
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8. Design, Synthesis, and Biological Evaluation of New Peripheral 5HT
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Minhee, Kim, Inseon, Hwang, Haushabhau S, Pagire, Suvarna H, Pagire, Wonsuk, Choi, Won Gun, Choi, Jihyeon, Yoon, Won Mi, Lee, Jin Sook, Song, Eun Kyung, Yoo, Seung Mi, Lee, Mi-Jin, Kim, Myung Ae, Bae, Dooseop, Kim, Heejong, Lee, Eun-Young, Lee, Jae-Han, Jeon, In-Kyu, Lee, Hail, Kim, and Jin Hee, Ahn
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Male ,Mice, Inbred ICR ,Drug Evaluation, Preclinical ,Diet, High-Fat ,Mice, Inbred C57BL ,Rats, Sprague-Dawley ,Mice ,HEK293 Cells ,Non-alcoholic Fatty Liver Disease ,Drug Design ,Microsomes, Liver ,Serotonin 5-HT2 Receptor Antagonists ,Animals ,Humans - Abstract
Nonalcoholic fatty liver disease (NAFLD) is increasingly prevalent worldwide, causing serious liver complications, including nonalcoholic steatohepatitis. Recent findings suggest that peripheral serotonin (5-hydroxytryptamine, 5HT) regulates energy homeostasis, including hepatic lipid metabolism. More specifically, liver-specific 5HT
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- 2020
9. PDK4 Deficiency Suppresses Hepatic Glucagon Signaling by Decreasing cAMP Levels
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Jae-Han Jeon, Inkyu Lee, Yong Hyun Jeon, Jeong Eun Kim, Woong Kwon, Younghoon Go, Nam Ho Jeoung, Ling He, Hye Jin Ham, Bo Yoon Park, Byung-Gyu Kim, Eun Kyung Yoo, Keun-Gyu Park, Robert A. Harris, and Seung Hoi Koo
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Male ,0301 basic medicine ,Pyruvate decarboxylation ,medicine.medical_specialty ,Pyruvate dehydrogenase kinase ,Endocrinology, Diabetes and Metabolism ,Blotting, Western ,PDK4 ,Protein Serine-Threonine Kinases ,Real-Time Polymerase Chain Reaction ,Pathophysiology ,Glucagon ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,Internal medicine ,Cyclic AMP ,Internal Medicine ,medicine ,Animals ,Beta oxidation ,Cells, Cultured ,Triglycerides ,Sulfonamides ,Kinase ,Gluconeogenesis ,Pyruvate Dehydrogenase Acetyl-Transferring Kinase ,Glucose Tolerance Test ,Isoquinolines ,Mice, Inbred C57BL ,030104 developmental biology ,Endocrinology ,Liver ,chemistry ,Hepatocytes ,Etomoxir - Abstract
In fasting or diabetes, gluconeogenic genes are transcriptionally activated by glucagon stimulation of the cAMP-protein kinase A (PKA)–CREB signaling pathway. Previous work showed pyruvate dehydrogenase kinase (PDK) inhibition in skeletal muscle increases pyruvate oxidation, which limits the availability of gluconeogenic substrates in the liver. However, this study found upregulation of hepatic PDK4 promoted glucagon-mediated expression of gluconeogenic genes, whereas knockdown or inhibition of hepatic PDK4 caused the opposite effect on gluconeogenic gene expression and decreased hepatic glucose production. Mechanistically, PDK4 deficiency decreased ATP levels, thus increasing phosphorylated AMPK (p-AMPK), which increased p-AMPK–sensitive phosphorylation of cyclic nucleotide phosphodiesterase 4B (p-PDE4B). This reduced cAMP levels and consequently p-CREB. Metabolic flux analysis showed that the reduction in ATP was a consequence of a diminished rate of fatty acid oxidation (FAO). However, overexpression of PDK4 increased FAO and increased ATP levels, which decreased p-AMPK and p-PDE4B and allowed greater accumulation of cAMP and p-CREB. The latter were abrogated by the FAO inhibitor etomoxir, suggesting a critical role for PDK4 in FAO stimulation and the regulation of cAMP levels. This finding strengthens the possibility of PDK4 as a target against diabetes.
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- 2018
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10. Discovery of Potent, Selective, and Orally Bioavailable Estrogen-Related Receptor-γ Inverse Agonists To Restore the Sodium Iodide Symporter Function in Anaplastic Thyroid Cancer
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Jungwook Chin, Jaeyoung Song, Hyun Dong Ji, Eun Kyung Yoo, Heeseok Yoon, Sang Bong Lee, Dong-Su Kim, Seungmi Lee, Jae-Eon Lee, Inkyu Lee, Kyung-Hee Kim, Keun-Gyu Park, Ji Sun Hwang, Sung Jin Cho, Jina Kim, Seong Heon Kim, Sang-Woo Lee, Ji Min Oh, Yong Hyun Jeon, Minseon Jeong, Hueng-Sik Choi, Su-Jeong Lee, Sungwoo Lee, and Hayoung Hwang
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Sodium-iodide symporter ,Drug Inverse Agonism ,Gene Expression ,Antineoplastic Agents ,Thyroid Carcinoma, Anaplastic ,01 natural sciences ,Iodine Radioisotopes ,03 medical and health sciences ,Estrogen-related receptor ,chemistry.chemical_compound ,Structure-Activity Relationship ,In vivo ,Cell Line, Tumor ,Drug Discovery ,medicine ,Inverse agonist ,Animals ,Humans ,Thyroid Neoplasms ,Anaplastic thyroid cancer ,Receptor ,030304 developmental biology ,0303 health sciences ,Mice, Inbred BALB C ,Molecular Structure ,Symporters ,Chemistry ,Estrogens ,medicine.disease ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,Tamoxifen ,Nuclear receptor ,Receptors, Estrogen ,Sodium iodide ,Cancer research ,Molecular Medicine ,Female - Abstract
An inverse agonist of estrogen-related receptor-γ (ERRγ), an orphan nuclear receptor encoded by Esrrg, enhances sodium iodide symporter-mediated radioiodine uptake in anaplastic thyroid cancer (ATC) cells, thereby facilitating responsiveness to radioiodine therapy in vitro. We synthesized potent, selective, and orally bioavailable ERRγ-inverse agonists and evaluated their activity by analyzing in vitro pharmacology and absorption, distribution, metabolism, excretion, and toxicity profiles. X-ray crystallographic analysis of the ligand and ERRγ complex showed that 35 completely binds to the target protein (PDB 6A6K). Our results showed improved radioiodine avidity in ATC cells through compound 35-mediated upregulation of iodide-handling genes, leading to enhanced responsiveness to radioiodine therapy in vitro. Importantly, in vivo 124I-positron emission tomography/computed tomography imaging revealed that 35 increases radioiodine avidity in CAL62 tumors. Collectively, these results demonstrated that 35 can...
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- 2019
11. Insights of a Lead Optimization Study and Biological Evaluation of Novel 4-Hydroxytamoxifen Analogs as Estrogen-Related Receptor γ (ERRγ) Inverse Agonists
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Inkyu Lee, Sung Jin Cho, Hueng-Sik Choi, Kyung-Hee Kim, Shinae Kim, Thoudam Debraj Singh, Heeseok Yoon, Hee-Jong Hwang, Yong Hyun Jeon, Seo Yeon Woo, Chun Young Im, Hayoung Hwang, Kim Hyoji, Jina Kim, Jae-Han Jeon, Eun Kyung Yoo, Sang-Wook Kim, Seong Heon Kim, Jungwook Chin, Oh-Bin Kwon, Sung Yeoun Hwang, Cho Joong-Heui, Seungmi Lee, and Wonseok Lee
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0301 basic medicine ,Dose-Response Relationship, Drug ,Molecular Structure ,Chemistry ,Pharmacology ,medicine.disease ,In vitro ,Cell Line ,Structure-Activity Relationship ,Tamoxifen ,03 medical and health sciences ,Estrogen-related receptor ,030104 developmental biology ,Receptors, Estrogen ,Pharmacokinetics ,In vivo ,Drug Discovery ,medicine ,Humans ,Molecular Medicine ,Inverse agonist ,Structure–activity relationship ,Anaplastic thyroid cancer ,Receptor - Abstract
We evaluated the in vitro pharmacology as well as the absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties of chemical entities that not only were shown to be highly selective agonists for ERRγ but also exhibited enhanced pharmacokinetic profile compared with 3 (GSK5182). 6g and 10b had comparable potency to 3 and were far more selective for ERRγ over the ERRα, -β, and ERα. The in vivo pharmacokinetic profiles of 6g and 10b were further evaluated, as they possessed superior in vitro ADMET profiles compared to the other compounds. Additionally, we observed a significant increase of fully glycosylated NIS protein, key protein for radioiodine therapy in anaplastic thyroid cancer (ATC), in 6g- or 10b-treated CAL62 cells, which indicated that these compounds could be promising enhancers for restoring NIS protein function in ATC cells. Thus, 6g and 10b possess advantageous druglike properties and can be used to potentially treat various ERRγ-related disorders.
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- 2016
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12. PKB/Akt phosphorylation of ERRγ contributes to insulin-mediated inhibition of hepatic gluconeogenesis
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Yong-Hoon Kim, Ho Zoon Chae, Dongryeol Ryu, Hueng Sik Choi, Brian A. Hemmings, Inkyu Lee, Chul-Ho Lee, Kyung Seok Kim, Eun Kyung Yoo, Seung Hoi Koo, Sudha B. Biddinger, Jeong Sun Kim, Keum Jin Yang, Yanning Wang, Jongsun Park, Debby Hynx, and Don Kyu Kim
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medicine.medical_specialty ,Chemistry ,Endocrinology, Diabetes and Metabolism ,Insulin ,medicine.medical_treatment ,Type 2 diabetes ,medicine.disease ,Endocrinology ,Insulin resistance ,Nuclear receptor ,Internal medicine ,Diabetes mellitus ,Internal Medicine ,medicine ,Transcriptional regulation ,Phosphorylation ,Receptor - Abstract
Aims/hypothesis Insulin resistance, a major contributor to the pathogenesis of type 2 diabetes, leads to increased hepatic glucose production (HGP) owing to an impaired ability of insulin to suppress hepatic gluconeogenesis. Nuclear receptor oestrogen-related receptor γ (ERRγ) is a major transcriptional regulator of hepatic gluconeogenesis. In this study, we investigated insulin-dependent post-translational modifications (PTMs) altering the transcriptional activity of ERRγ for the regulation of hepatic gluconeogenesis.
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- 2014
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13. Regulation of Acetylation of Histone Deacetylase 2 by p300/CBP-Associated Factor/Histone Deacetylase 5 in the Development of Cardiac Hypertrophy
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Woo Jin Park, Eun Kyung Yoo, Nakwon Choe, Gwang Hyeon Eom, Jae Gyun Oh, Jung Joon Min, Jong-Keun Kim, Hyun Kook, Rhonda Bassel-Duby, Yoon Seok Nam, Vu H. Nguyen, Gaeun Kang, Hyun Ki Min, Inkyu Lee, and Eric N. Olson
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Histone deacetylase 5 ,Physiology ,HDAC11 ,Histone deacetylase 2 ,HDAC10 ,Acetylation ,Cardiomegaly ,Histone acetyltransferase ,SAP30 ,Biology ,HDAC4 ,Histone Deacetylases ,Rats ,Histone Deacetylase Inhibitors ,Rats, Sprague-Dawley ,Mice ,Mutation ,Cancer research ,biology.protein ,Animals ,Myocytes, Cardiac ,p300-CBP Transcription Factors ,Phosphorylation ,Cardiology and Cardiovascular Medicine - Abstract
Rationale: Histone deacetylases (HDACs) are closely involved in cardiac reprogramming. Although the functional roles of class I and class IIa HDACs are well established, the significance of interclass crosstalk in the development of cardiac hypertrophy remains unclear. Objective: Recently, we suggested that casein kinase 2α1–dependent phosphorylation of HDAC2 leads to enzymatic activation, which in turn induces cardiac hypertrophy. Here we report an alternative post-translational activation mechanism of HDAC2 that involves acetylation of HDAC2 mediated by p300/CBP-associated factor/HDAC5. Methods and Results: Hdac2 was acetylated in response to hypertrophic stresses in both cardiomyocytes and a mouse model. Acetylation was reduced by a histone acetyltransferase inhibitor but was increased by a nonspecific HDAC inhibitor. The enzymatic activity of Hdac2 was positively correlated with its acetylation status. p300/CBP-associated factor bound to Hdac2 and induced acetylation. The HDAC2 K75 residue was responsible for hypertrophic stress–induced acetylation. The acetylation-resistant Hdac2 K75R showed a significant decrease in phosphorylation on S394, which led to the loss of intrinsic activity. Hdac5, one of class IIa HDACs, directly deacetylated Hdac2. Acetylation of Hdac2 was increased in Hdac5-null mice. When an acetylation-mimicking mutant of Hdac2 was infected into cardiomyocytes, the antihypertrophic effect of either nuclear tethering of Hdac5 with leptomycin B or Hdac5 overexpression was reduced. Conclusions: Taken together, our results suggest a novel mechanism by which the balance of HDAC2 acetylation is regulated by p300/CBP-associated factor and HDAC5 in the development of cardiac hypertrophy.
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- 2014
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14. Correction to Discovery of Novel Pyruvate Dehydrogenase Kinase 4 Inhibitors for Potential Oral Treatment of Metabolic Diseases
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Ashok Kumar Jaladi, Eun Kyung Yoo, Eun Jung Bae, Yong Hyun Jeon, Yoon Kyung Jang, Dahye Lee, Minhee Kim, Jin Sook Song, Won-Il Choi, Haushabhau S. Pagire, Mahesh Dighe, Seungmi Lee, Inkyu Lee, Jin Hee Ahn, Myung Ae Bae, Hee Eon Gim, Kwang-Hyeon Liu, Kyu Myung Lee, Kwan-Young Jung, Young In Chi, Tae-Ho Lee, Jae-Han Jeon, Ga-Hyun Lee, Sungmi Park, and Suvarna H. Pagire
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Oral treatment ,Pyruvate dehydrogenase kinase 4 ,Biochemistry ,Chemistry ,Drug Discovery ,Molecular Medicine - Published
- 2019
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15. Transcriptional control of hydrogen peroxide homeostasis regulates ground tissue patterning in the Arabidopsis root
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Jiyeong Oh, Ji Won Choi, Sejeong Jang, Seung Woo Kim, Jung-Ok Heo, Eun Kyung Yoon, Soo-Hwan Kim, and Jun Lim
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Arabidopsis ,class III peroxidase ,gibberellic acid ,ground tissue ,hydrogen peroxide ,middle cortex formation ,Plant culture ,SB1-1110 - Abstract
In multicellular organisms, including higher plants, asymmetric cell divisions (ACDs) play a crucial role in generating distinct cell types. The Arabidopsis root ground tissue initially has two layers: endodermis (inside) and cortex (outside). In the mature root, the endodermis undergoes additional ACDs to produce the endodermis itself and the middle cortex (MC), located between the endodermis and the pre-existing cortex. In the Arabidopsis root, gibberellic acid (GA) deficiency and hydrogen peroxide (H2O2) precociously induced more frequent ACDs in the endodermis for MC formation. Thus, these findings suggest that GA and H2O2 play roles in regulating the timing and extent of MC formation. However, details of the molecular interaction between GA signaling and H2O2 homeostasis remain elusive. In this study, we identified the PEROXIDASE 34 (PRX34) gene, which encodes a class III peroxidase, as a molecular link to elucidate the interconnected regulatory network involved in H2O2- and GA-mediated MC formation. Under normal conditions, prx34 showed a reduced frequency of MC formation, whereas the occurrence of MC in prx34 was restored to nearly WT levels in the presence of H2O2. Our results suggest that PRX34 plays a role in H2O2-mediated MC production. Furthermore, we provide evidence that SCARECROW-LIKE 3 (SCL3) regulates H2O2 homeostasis by controlling transcription of PRX34 during root ground tissue maturation. Taken together, our findings provide new insights into how H2O2 homeostasis is achieved by SCL3 to ensure correct radial tissue patterning in the Arabidopsis root.
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- 2023
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16. Synthesis and biological evaluation of novel 4-hydroxytamoxifen analogs as estrogen-related receptor gamma inverse agonists
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Yong Hyun Jeon, Sung Jin Cho, Cho Joong-Heui, Hueng-Sik Choi, Kyung-Hee Kim, Inkyu Lee, Chun Young Im, Jina Kim, Eun Kyung Yoo, Hayoung Hwang, Seoyeon Woo, Jae-Han Jeon, Seong Heon Kim, Seungyun Yoon, Hwang Hee Jong, Jungwook Chin, Suk Kyoon Yoon, Kyung-ah Seo, Jaeyoung Song, and Nam Doo Kim
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0301 basic medicine ,Drug Inverse Agonism ,Estrogen receptor ,Pharmacology ,Ligands ,Small Molecule Libraries ,03 medical and health sciences ,Inhibitory Concentration 50 ,Structure-Activity Relationship ,0302 clinical medicine ,Drug Discovery ,Inverse agonist ,Humans ,Receptor ,IC50 ,Chemistry ,Organic Chemistry ,General Medicine ,Ligand (biochemistry) ,Tamoxifen ,030104 developmental biology ,Nuclear receptor ,Receptors, Estrogen ,030220 oncology & carcinogenesis ,Toxicity ,Estrogen-related receptor gamma - Abstract
Estrogen-related receptor gamma (ERRγ) has recently been recognized as an attractive target for treating inflammation, cancer, and metabolic disorders. Herein, we discovered and demonstrated the in vitro pharmacology as well as the absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties of chemical entities that could act as highly selective inverse agonists for ERRγ. The results were comparable to those for GSK5182 (4), a leading ERRγ inverse agonist ligand. Briefly, the half-maximal inhibitory concentration (IC50) range of the synthesized compounds for ERRγ was 0.1–10 μM. Impressively, compound 24e exhibited potency comparable to 4 but was more selective for ERRγ over three other subtypes: ERRα, ERRβ, and estrogen receptor α. Furthermore, compound 24e exhibited a superior in vitro ADMET profile compared to the other compounds. Thus, the newly synthesized class of ERRγ inverse agonists could be lead candidates for developing clinical therapies for ERRγ-related disorders.
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- 2016
17. Effects of PGC-1α on TNF-α–Induced MCP-1 and VCAM-1 Expression and NF-κB Activation in Human Aortic Smooth Muscle and Endothelial Cells
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Won Gu Jang, Yoon-Nyun Kim, Hyoung Tae Kim, Hye Jin Kim, Bo-Wan Kim, Eun-Kyung Yoo, In Kyu Lee, Keun-Gyu Park, Hye Soon Kim, Joong-Yeol Park, Ki-Up Lee, Jung-Guk Kim, and Young Ho Kim
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Mitochondrial ROS ,Endothelium ,Physiology ,Clinical Biochemistry ,Vascular Cell Adhesion Molecule-1 ,Aorta, Thoracic ,Biology ,medicine.disease_cause ,Biochemistry ,Muscle, Smooth, Vascular ,Proinflammatory cytokine ,chemistry.chemical_compound ,medicine ,Humans ,VCAM-1 ,Molecular Biology ,Cells, Cultured ,Chemokine CCL2 ,Heat-Shock Proteins ,DNA Primers ,General Environmental Science ,Base Sequence ,Tumor Necrosis Factor-alpha ,NF-kappa B ,NADPH Oxidases ,Cell Biology ,Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha ,Recombinant Proteins ,Cell biology ,Vascular endothelial growth factor B ,medicine.anatomical_structure ,chemistry ,General Earth and Planetary Sciences ,Tumor necrosis factor alpha ,Endothelium, Vascular ,Reactive Oxygen Species ,Intracellular ,Oxidative stress ,Transcription Factors - Abstract
Increased oxidative stress in vascular cells is implicated in the pathogenesis of atherosclerosis. Reactive oxygen species (ROS) induce vascular inflammation via the proinflammatory cytokine/NF-kappaB pathway. Several lines of evidence suggest that peroxisome proliferator-activated receptor-gamma coactivator 1-alpha (PGC-1alpha) is an important regulator of intracellular ROS levels. However, no studies have examined the effects of PGC-1alpha on this process. We investigated the effects of PGC-1alpha on inflammatory molecule expression and activity of the redox-sensitive transcription factor, NF-kappaB, in vascular cells. PGC-1alpha expressed in human aortic smooth (HASMCs) and endothelial cells (HAECs) is upregulated by AMP-activated protein kinase activators, including metformin, rosiglitazone and alpha-lipoic acid. Tumor necrosis factor-alpha (TNF-alpha), a major proinflammatory factor in the development of vascular inflammation, stimulates intracellular ROS production through an increase in both mitochondrial ROS and NAD(P)H oxidase activity. Adenovirus-mediated overexpression of the PGC-1alpha gene in HASMCs and HAECs leads to a significant reduction in intracellular and mitochondrial ROS production as well as NAD(P)H oxidase activity. Consequently, NF-kappaB activity and MCP-1 and VCAM-1 induced by TNF-alpha are suppressed. Our data support the possibility that agents stimulating PGC-1alpha expression in the vasculature aid in preventing the development of atherosclerosis.
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- 2007
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18. O-GlcNAcylation of Orphan Nuclear Receptor Estrogen-Related Receptor γ Promotes Hepatic Gluconeogenesis
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Jeong Sun Kim, Yong-Hoon Kim, Eun Kyung Yoo, Chul-Ho Lee, Yoon Seok Jung, Han Byeol Kim, Byung-Gyu Kim, Robert A. Harris, Hueng Sik Choi, Sunghoon Kim, Inkyu Lee, Don Kyu Kim, Jin Won Cho, and Jagannath Misra
- Subjects
0301 basic medicine ,Male ,Glycosylation ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Protein degradation ,Biology ,N-Acetylglucosaminyltransferases ,Mass Spectrometry ,Serine ,03 medical and health sciences ,Estrogen-related receptor ,Mice ,0302 clinical medicine ,Internal Medicine ,medicine ,Animals ,Receptor ,Cells, Cultured ,Insulin ,Gluconeogenesis ,Orphan Nuclear Receptors ,Mice, Inbred C57BL ,030104 developmental biology ,Biochemistry ,Nuclear receptor ,Liver ,Receptors, Estrogen ,030220 oncology & carcinogenesis ,Phosphorylation ,Protein Processing, Post-Translational - Abstract
Estrogen-related receptor γ (ERRγ) is a major positive regulator of hepatic gluconeogenesis. Its transcriptional activity is suppressed by phosphorylation signaled by insulin in the fed state, but whether posttranslational modification alters its gluconeogenic activity in the fasted state is not known. Metabolically active hepatocytes direct a small amount of glucose into the hexosamine biosynthetic pathway, leading to protein O-GlcNAcylation. In this study, we demonstrate that ERRγ is O-GlcNAcylated by O-GlcNAc transferase in the fasted state. This stabilizes the protein by inhibiting proteasome-mediated protein degradation, increasing ERRγ recruitment to gluconeogenic gene promoters. Mass spectrometry identifies two serine residues (S317, S319) present in the ERRγ ligand-binding domain that are O-GlcNAcylated. Mutation of these residues destabilizes ERRγ protein and blocks the ability of ERRγ to induce gluconeogenesis in vivo. The impact of this pathway on gluconeogenesis in vivo was confirmed by the observation that decreasing the amount of O-GlcNAcylated ERRγ by overexpressing the deglycosylating enzyme O-GlcNAcase decreases ERRγ-dependent glucose production in fasted mice. We conclude that O-GlcNAcylation of ERRγ serves as a major signal to promote hepatic gluconeogenesis.
- Published
- 2015
19. Effect of ramosetron on the QT interval during sevoflurane anaesthesia in children: a prospective observational study
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Hee-Soo Kim, Jin-Tae Kim, Eun-Kyung Yoo, Ji Hyun Lee, and In-Kyung Song
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Male ,Methyl Ethers ,QT interval ,Sevoflurane ,Ramosetron ,chemistry.chemical_compound ,Heart Rate ,Heart rate ,Medicine ,Humans ,cardiovascular diseases ,Prospective Studies ,Adverse effect ,Child ,business.industry ,Anesthesiology and Pain Medicine ,Treatment Outcome ,chemistry ,Concomitant ,Anesthesia ,Child, Preschool ,Anesthetics, Inhalation ,Antiemetics ,Observational study ,Benzimidazoles ,Drug Therapy, Combination ,Female ,Analysis of variance ,business ,medicine.drug - Abstract
BACKGROUND We investigated the effects of concomitant administration of sevoflurane and ramosetron on the QT interval, the interval between the peak and end of the T wave (Tpe) and Tpe/QT ratio in children. OBJECTIVES To compare the effects of concomitant administration of ramosetron and sevoflurane on heart rate corrected interval with Bazett's formula (QTc), Tpe interval and Tpe/QT ratio. DESIGN A prospective observational study. SETTING Elective orthopaedic surgery with patient-controlled analgesia. PATIENTS Forty children aged between 3 and 12 years. INTERVENTION ECG recordings were collected before induction (BASE), before sevoflurane administration (SEVO) and after the administration of ramosetron (SEVO and R). MAIN OUTCOME MEASURES The heart rate corrected interval with Bazett's formula (QTc), Tpe interval and Tpe/QT ratio were calculated and the changes were analysed using repeated-measures analysis of variance (ANOVA). RESULTS The QTc interval at BASE was 388.5 ± 29.3 ms. It increased with sevoflurane anaesthesia to 414.9 ± 21.4 ms and did not change with the administration of ramosetron (418.2 ± 23.0 ms). The Tpe interval and Tpe/QT ratio did not differ between measurements. No ventricular arrhythmias occurred during the study. CONCLUSION Ramosetron was not associated with prolongation of the QTc interval when it was given concomitantly with sevoflurane in children. No ventricular arrhythmias or other adverse effects occurred during the study.
- Published
- 2014
20. Propofol-ketamine or propofol-remifentanil for deep sedation and analgesia in pediatric patients undergoing burn dressing changes: a randomized clinical trial
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Jin Young Hwang, Chong Soo Kim, Seong Won Min, Tai Kyung Seol, Eun Kyung Yoo, and Jin Kyu Lim
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Male ,medicine.medical_specialty ,Nausea ,Sedation ,Remifentanil ,Pain ,Piperidines ,Interquartile range ,medicine ,Humans ,Hypnotics and Sedatives ,Pain Management ,Ketamine ,Propofol ,Anesthetics, Dissociative ,business.industry ,Infant ,Bandages ,Surgery ,Anesthesiology and Pain Medicine ,Treatment Outcome ,Anesthesia ,Child, Preschool ,Pediatrics, Perinatology and Child Health ,Anesthetic ,Anesthesia Recovery Period ,Vomiting ,Drug Therapy, Combination ,Female ,medicine.symptom ,Analgesia ,Deep Sedation ,business ,Burns ,Anesthetics, Intravenous ,medicine.drug - Abstract
SummaryObjective In this study, we compared the propofol–ketamine and propofol–remifentanil combinations for deep sedation and analgesia during pediatric burn wound dressing changes. Methods Fifty pediatric patients aged 12–36 months, undergoing burn wound dressing changes, were randomly assigned to receive propofol–remifentanil (group PR) or propofol–ketamine (group PK) for deep sedation and analgesia. Patients in the group PR received 2 mg·kg−1 propofol and 0.1 μg·kg−1 remifentanil, and 0.05 μg·kg−1·min−1 remifentanil was infused continuously until the end of the procedure. Patients in the group PK received 2 mg·kg−1 propofol and 1 mg·kg−1 ketamine, and the same volume of isotonic saline was infused continuously until the end of the procedure. Additional propofol with remifentanil or ketamine was administered when required. Hemodynamic variables, drug requirements, occurrence of patient movement, surgeon's satisfaction score, recovery time, and the incidence of adverse events were recorded throughout the procedure and recovery. Results Recovery time was significantly shorter in the group PR compared to that in the group PK (10.3 [9.1–11.5] min vs 22.5 [20.3–25.6] min, median [interquartile range], respectively; P
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- 2014
21. (Don’t) Look Up!: Is short-root just a short‐root plant?
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Eun Kyung Yoon, Jiyeong Oh, and Jun Lim
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Arabidopsis ,GRAS transcription factor ,shoot development ,root development ,SCARECROW (SCR) ,SHORT-ROOT (SHR) ,Plant culture ,SB1-1110 - Abstract
SHORT-ROOT (SHR) is a mobile transcription factor that plays important roles in ground tissue patterning, stem cell niche specification and maintenance, and vascular development in Arabidopsis roots. Although mRNA and protein of SHR are also found in hypocotyls, inflorescence stems, and leaves, its role in the above-ground organs has been less explored. In most developmental cases, SHR, together with its partner SCARECROW (SCR), regulates the expression of downstream target genes in controlling formative and proliferative cell divisions. Accumulating evidence on the regulatory role of SHR in shoots suggests that SHR may also play key roles in the above-ground organs. Interestingly, recent work has provided new evidence that SHR is also required for cell elongation in the hypocotyl of the etiolated seedling. This suggests that the novel roles of SHR and SHR-mediated regulatory networks can be found in shoots. Furthermore, comparative research on SHR function in roots and shoots will broaden and deepen our understanding of plant growth and development.
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- 2022
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22. The utilisation of Complementary and Alternative Medicine (CAM) among ethnic minorities in South Korea
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Jung Hye Hwang, Eun Kyung Yoo, Woon-Yong Kim, and Dong Woon Han
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Complementary Therapies ,medicine.medical_specialty ,animal structures ,Cross-sectional study ,Alternative medicine ,Ethnic group ,Acupuncture Therapy ,Positive perception ,Republic of Korea ,medicine ,Ethnicity ,Humans ,Minority Groups ,High prevalence ,Modalities ,business.industry ,General Medicine ,Vitamins ,Middle Aged ,Medicine, Korean Traditional ,Self Care ,Cross-Sectional Studies ,Cultural barriers ,Complementary and alternative medicine ,Family medicine ,Female ,Survey instrument ,business ,Attitude to Health ,Phytotherapy ,Research Article - Abstract
BackgroundRace has been reported to affect the use of complementary and alternative medicine (CAM), but there is very little research on the use of CAM by ethnicity in Korea. This study explores the prevalence of CAM use among ethnic minorities in South Korea.MethodsThe design is a descriptive and cross-sectional study. A convenience sample of ethnic minorities was recruited from two public healthcare centres in Gyeonggi province. The survey instrument included 37 questions regarding CAM use, factors influencing use of CAM, self-health management, and the socio-demographic profile of study participants.ResultsSixty-two percent of study participants reported the use of CAM. Multivitamins (53.3%), acupuncture (48.9%), and traditional Korean herbal medicine (38.9%) were popular CAM modalities in our sample. Other notable CAM modalities included herbal plants, therapeutic massage, and moxibustion therapy. The majority of CAM users (52.2%) received CAM services to treat diseases or as a secondary treatment while receiving conventional care. Having positive perceptions toward the effectiveness of CAM was a major determining factor in CAM use.ConclusionsPhysicians need to be aware of the fact that many ethnic minorities use CAM therapies. Many CAM users reported that they want doctors to know about their CAM use and have a basic understanding of traditional medicine in their home country. Overcoming language and cultural barriers will help reduce unwanted medical complications. High prevalence of CAM use among ethnic minorities in our study warrants further studies using larger sample population.
- Published
- 2013
23. Clusterin decreases hepatic SREBP-1c expression and lipid accumulation
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Yun-A Jung, Mi-Kyung Kim, Keun-Gyu Park, Inkyu Lee, Byoung Kuk Jang, Hye-Young Seo, and Eun-Kyung Yoo
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Male ,medicine.medical_specialty ,medicine.medical_treatment ,digestive system ,Mice ,Endocrinology ,Insulin resistance ,Transcription (biology) ,Internal medicine ,Gene expression ,polycyclic compounds ,medicine ,Tumor Cells, Cultured ,Animals ,Humans ,Liver X receptor ,Mice, Knockout ,Clusterin ,biology ,Insulin ,Lipogenesis ,food and beverages ,Hep G2 Cells ,medicine.disease ,Lipid Metabolism ,eye diseases ,Rats ,Mice, Inbred C57BL ,medicine.anatomical_structure ,Gene Expression Regulation ,Liver ,Hepatocyte ,biology.protein ,lipids (amino acids, peptides, and proteins) ,Steatosis ,Sterol Regulatory Element Binding Protein 1 - Abstract
Hepatic steatosis is emerging as the most important cause of chronic liver disease and is associated with the increasing incidence of obesity with insulin resistance. Sterol regulatory binding protein-1c (SREBP-1c) is a master regulator of lipogenic gene expression in the liver. Hyperinsulinemia induces SREBP-1c transcription through liver X receptor (LXR), specificity protein 1, and SREBP-1c itself. Clusterin, an 80-kDa disulfide-linked heterodimeric protein, has been functionally implicated in several physiological processes including lipid transport; however, little is known about its effect on hepatic lipogenesis. The present study examined whether clusterin regulates SREBP-1c expression and lipid accumulation in the liver. Adenovirus-mediated overexpression of clusterin inhibited insulin- or LXR agonist-stimulated SREBP-1c expression in cultured liver cells. In reporter assays, clusterin inhibited SREBP-1c promoter activity. Moreover, adenovirus-mediated overexpression of clusterin in the livers of mice fed a high-fat diet inhibited hepatic steatosis through the inhibition of SREBP-1c expression. Reporter and gel shift assays showed that clusterin inhibits SREBP-1c expression via the repression of LXR and specificity protein 1 activity. This study shows that clusterin inhibits hepatic lipid accumulation through the inhibition of SREBP-1c expression and suggests that clusterin is a negative regulator of SREBP-1c expression and hepatic lipogenesis.
- Published
- 2013
24. PDK4 Deficiency Suppresses Hepatic Glucagon Signaling by Decreasing cAMP Levels.
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Bo-Yoon Park, Park, Bo-Yoon, Harris, Robert A., Jeon, Jae-Han, Park, Keun-Gyu, Lee, In-Kyu, Go, Younghoon, Kim, Byung-Gyu, He, Ling, Jae-Han Jeon, Keun-Gyu Park, In-Kyu Lee, Hye Jin Ham, Jeong-Eun Kim, Eun Kyung Yoo, Woong Hee Kwon, Ham, Hye Jin, Kim, Jeong-Eun, Yoo, Eun Kyung, and Kwon, Woong Hee
- Subjects
PYRUVATE dehydrogenase kinase ,CYCLIC adenylic acid ,GLUCAGON regulation ,SKELETAL muscle ,GENE expression ,PHOSPHORYLATION ,ANIMAL experimentation ,CELL culture ,COMPARATIVE studies ,EPITHELIAL cells ,GLUCAGON ,GLUCOSE tolerance tests ,ISOQUINOLINE ,LIVER ,RESEARCH methodology ,MEDICAL cooperation ,METABOLISM ,MICE ,POLYMERASE chain reaction ,RESEARCH ,RESEARCH funding ,SULFONAMIDES ,TRANSFERASES ,TRIGLYCERIDES ,WESTERN immunoblotting ,EVALUATION research ,PHARMACODYNAMICS - Abstract
In fasting or diabetes, gluconeogenic genes are transcriptionally activated by glucagon stimulation of the cAMP-protein kinase A (PKA)-CREB signaling pathway. Previous work showed pyruvate dehydrogenase kinase (PDK) inhibition in skeletal muscle increases pyruvate oxidation, which limits the availability of gluconeogenic substrates in the liver. However, this study found upregulation of hepatic PDK4 promoted glucagon-mediated expression of gluconeogenic genes, whereas knockdown or inhibition of hepatic PDK4 caused the opposite effect on gluconeogenic gene expression and decreased hepatic glucose production. Mechanistically, PDK4 deficiency decreased ATP levels, thus increasing phosphorylated AMPK (p-AMPK), which increased p-AMPK-sensitive phosphorylation of cyclic nucleotide phosphodiesterase 4B (p-PDE4B). This reduced cAMP levels and consequently p-CREB. Metabolic flux analysis showed that the reduction in ATP was a consequence of a diminished rate of fatty acid oxidation (FAO). However, overexpression of PDK4 increased FAO and increased ATP levels, which decreased p-AMPK and p-PDE4B and allowed greater accumulation of cAMP and p-CREB. The latter were abrogated by the FAO inhibitor etomoxir, suggesting a critical role for PDK4 in FAO stimulation and the regulation of cAMP levels. This finding strengthens the possibility of PDK4 as a target against diabetes. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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25. Protective role of clusterin/apolipoprotein J against neointimal hyperplasia via antiproliferative effect on vascular smooth muscle cells and cytoprotective effect on endothelial cells
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Nam Ho Jeoung, In Sun Park, Han Jong Kim, Eun Kyung Yoo, Jeong Kook Kim, Masataka Sata, Inkyu Lee, Keun-Gyu Park, Ki Up Lee, Hyo-Jeong Lee, Bon Hong Min, Joon Young Kim, Bruce J. Aronow, Choi Young Keun, and Chul-Ho Lee
- Subjects
Male ,medicine.medical_specialty ,Vascular smooth muscle ,Myocytes, Smooth Muscle ,Biology ,Retinoblastoma Protein ,Umbilical vein ,Muscle, Smooth, Vascular ,Rats, Sprague-Dawley ,Mice ,Downregulation and upregulation ,Cell Movement ,Internal medicine ,medicine ,Myocyte ,Animals ,Phosphorylation ,Cell Proliferation ,Neointimal hyperplasia ,Hyperplasia ,Clusterin ,G1 Phase ,NF-kappa B ,Endothelial Cells ,DNA ,medicine.disease ,Rats ,Endothelial stem cell ,Mice, Inbred C57BL ,Endocrinology ,Matrix Metalloproteinase 9 ,Cytoprotection ,Cancer research ,biology.protein ,Cardiology and Cardiovascular Medicine ,Tunica Intima - Abstract
Objective— Clusterin is induced in vascular smooth muscle cells (VSMCs) during atherosclerosis and injury-induced neointimal hyperplasia. However, its functional roles in VSMCs and endothelial cells remain controversial and elusive. This study was undertaken to clarify the role of clusterin in neointimal hyperplasia and elucidate its mechanism of action. Methods and Results— Adenovirus-mediated overexpression of clusterin (Ad-Clu) repressed TNF-α–stimulated expression of MCP-1, fractalkine, ICAM-1, VCAM-1, and MMP-9, leading to inhibition of VSMC migration. Both Ad-Clu and secreted clusterin suppressed VSMC proliferation by inhibiting DNA synthesis, but not by inducing apoptosis. Ad-Clu upregulated p53 and p21 cip1/waf1 but downregulated cyclins D and E, leading to suppression of pRb phosphorylation and subsequent induction of G1 arrest in VSMCs. Clusterin deficiency augmented VSMC proliferation in vitro and accelerated neointimal hyperplasia in vivo, but concomitantly impaired reendothelialization in wire-injured murine femoral arteries. Moreover, Ad-Clu significantly reduced neointimal thickening in balloon-injured rat carotid arteries. Clusterin also diminished TNF-α–induced apoptosis of human umbilical vein endothelial cells and restored endothelial nitric oxide synthase expression suppressed by TNF-α. Conclusion— These results suggest that upregulation of clusterin during vascular injury may be a protective response against, rather than a causative response to, the development of neointimal hyperplasia.
- Published
- 2009
26. Information Behaviors of HCI Professionals: Design of Intuitive Reference System for Technologies
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Yong-Beom Lee, Myung-Hyun Yoo, and Eun-kyung Yoo
- Subjects
Information visualization ,Computer science ,business.industry ,Human–computer interaction ,Information seeking ,New product development ,Technology roadmap ,Interaction design ,User interface ,Tracing ,business ,Work experience - Abstract
Technology roadmaps are often referred for better decision making by HCI professionals who connect human factors with product development and innovation. We conducted user study that explore information seeking and tracing behaviors in using technology roadmap. The research revealed that HCI professionals exhibit distinctive patterns in using technology roadmap, depending on their expertise in technical knowledge and work experience. Finally, we designed new user interface of an interactive technology roadmap system based on the research findings. We demonstrated its usefulness in seeking task-dependent information, intuitiveness in information visualization, and easiness to use as a reference for technologies.
- Published
- 2007
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27. Insights of a Lead Optimization Study and Biological Evaluation of Novel 4-Hydroxytamoxifen Analogs as Estrogen-Related Receptor γ (ERRγ) Inverse Agonists.
- Author
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Jina Kim, Seo Yeon Woo, Chun Young Im, Eun Kyung Yoo, Seungmi Lee, Hyo-Ji Kim, Hee-Jong Hwang, Joong-heui Cho, Won Seok Lee, Heeseok Yoon, Shinae Kim, Oh-bin Kwon, Hayoung Hwang, Kyung-Hee Kim, Jae-Han Jeon, Thoudam Debraj Singh, Sang Wook Kim, Sung Yeoun Hwang, Hueng-Sik Choi, and In-Kyu Lee
- Published
- 2016
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28. O-GlcNAcylation of Orphan Nuclear Receptor Estrogen-Related Receptor γ Promotes Hepatic Gluconeogenesis.
- Author
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Jagannath Misra, Don-Kyu Kim, Yoon Seok Jung, Han Byeol Kim, Yong-Hoon Kim, Eun-Kyung Yoo, Byung Gyu Kim, Sunghoon Kim, In-Kyu Lee, Harris, Robert A., Jeong-Sun Kim, Chul-Ho Lee, Jin Won Cho, Hueng-Sik Choi, Misra, Jagannath, Kim, Don-Kyu, Jung, Yoon Seok, Kim, Han Byeol, Kim, Yong-Hoon, and Yoo, Eun-Kyung
- Subjects
GLUCONEOGENESIS ,ESTROGEN agonists ,PROTEOLYSIS kinetics ,PROTEIN analysis ,GENE expression ,PROTEIN metabolism ,SERINE metabolism ,ANIMAL experimentation ,CELL culture ,CELL receptors ,GLYCOSYLATION ,LIVER ,MASS spectrometry ,METABOLISM ,MICE ,PROTEINS ,TRANSFERASES ,SERINE - Abstract
Estrogen-related receptor γ (ERRγ) is a major positive regulator of hepatic gluconeogenesis. Its transcriptional activity is suppressed by phosphorylation signaled by insulin in the fed state, but whether posttranslational modification alters its gluconeogenic activity in the fasted state is not known. Metabolically active hepatocytes direct a small amount of glucose into the hexosamine biosynthetic pathway, leading to protein O-GlcNAcylation. In this study, we demonstrate that ERRγ is O-GlcNAcylated by O-GlcNAc transferase in the fasted state. This stabilizes the protein by inhibiting proteasome-mediated protein degradation, increasing ERRγ recruitment to gluconeogenic gene promoters. Mass spectrometry identifies two serine residues (S317, S319) present in the ERRγ ligand-binding domain that are O-GlcNAcylated. Mutation of these residues destabilizes ERRγ protein and blocks the ability of ERRγ to induce gluconeogenesis in vivo. The impact of this pathway on gluconeogenesis in vivo was confirmed by the observation that decreasing the amount of O-GlcNAcylated ERRγ by overexpressing the deglycosylating enzyme O-GlcNAcase decreases ERRγ-dependent glucose production in fasted mice. We conclude that O-GlcNAcylation of ERRγ serves as a major signal to promote hepatic gluconeogenesis. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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29. Abstract 610: Metformin augments rituximab and chemotherapeutic agents-induced apoptosis via mTOR inhibition in rituximab-resistant B lymphoma cell lines
- Author
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Eun Kyung Yoo, Myung Soo Hyun, ChuHee Lee, Kyung Hee Lee, Min Kyoung Kim, Min Kyu Kang, and Nam-Yi Kim
- Subjects
Cancer Research ,business.industry ,medicine.disease ,Lymphoma ,Metformin ,Oncology ,Apoptosis ,Cell culture ,Cancer research ,medicine ,Rituximab ,business ,PI3K/AKT/mTOR pathway ,medicine.drug - Abstract
With elusive mechanisms, a subgroup of NHL patients who treated with rituximab in combination with cytotoxic chemotherapeutic agents becomes unresponsive. Patients who relapsed lymphoma are known to have poorer outcome when treated with rituximab compared with treated without rituximab. Since activation of mTOR pathway has been recently suggested for progression of NHL, especially in salvage setting, we'd like to examine the effect of metformin which inhibits mTOR pathway in rituximab-resistant NHL. Three lymphoma cell lines (Raji, Raji-2R, Raji-4RH) were used, which were kindly given by Dr Czuczman MS from Rosewell Park Cancer Institute (Ref. Czuczmana MS et al. Clin Cancer Res 2008;14:1561, 2008;14:1550). These cells were treated with cisplatin, adriamycin, vincristine and rituximab in the absence or presence of metformin for 24, 48, 72 hrs. Cell growth and proliferation was evaluated by MTT assay and cell cycle progression was determined FACS analysis. To characterize molecular mechanisms involved in metformin-induced inhibition of cell proliferation, the level of BAX, BAK, Bcl-2, Bcl-XL, Mcl-1, AMPK, pAMPK, pACC, mTOR, p70S6K and S6K was determined by western blot analysis. Compared with rituximab-sensitive cell line (RSCL) which is parental lymphoma cell, Raji, rituximab-resistant cell lines (RRCLs), that are Raji-2R and Raji-4RH, have shown decreased cytotoxicity in response to chemotherapeutic agents including cisplatin, adriamycin and vincristine as well as rituximab. However, cytotoxic effect of these chemotherapeutic agents and rituximab was improved in combination of metformin in both RSCL and RRCLs. To us surprise, a better synergistic inhibition of cell proliferation was found in RRCLs as a result of combination of metformin and chemotherapeutic agents or rituximab, suggesting that intracellular signaling pathway induced by metformin might not be overlapped to that by chemotherapeutic agent and rituximab. Notably, it has known that in RRCLs, the level of proapototic proteins, BAX, BAK, is relatively low compared to in RSCL decreased, but the expression of anti-apoptotic protein and AMPK activity is increased and dysregulation of mTOR pathway is found. Our data showed that metformin restored dysregulation of mTOR pathway in RRCLs, since activation of p70S6K and S6K posphorylation was decreased. At the same time, expression of BAX and BAK was increased and that of anti-apoptotic proteins was decreased. Metformin enhances rituximab-induced and chemotherapy-induced apoptosis via mTOR inhibition in rituximab-resistant NHL. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 610.
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- 2010
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30. Effect of ramosetron on the QT interval during sevoflurane anaesthesia in children.
- Author
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Ji-Hyun Lee, Eun-Kyung Yoo, In-Kyung Song, Jin-Tae Kim, and Hee-Soo Kim
- Published
- 2015
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31. Effects of PGC-1? on TNF-??Induced MCP-1 and VCAM-1 Expression and NF-?B Activation in Human Aortic Smooth Muscle and Endothelial Cells
- Author
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Hye-Jin Kim, Keun-Gyu Park, Eun-Kyung Yoo, Young-Ho Kim, Yoon-Nyun Kim, Hye-Soon Kim, Hyoung Tae Kim, Joong-Yeol Park, Ki-Up Lee, Won Gu Jang, Jung-Guk Kim, Bo-Wan Kim, and In-Kyu Lee
- Subjects
Physiology ,Clinical Biochemistry ,General Earth and Planetary Sciences ,Cell Biology ,Molecular Biology ,Biochemistry ,General Environmental Science - Published
- 2006
- Full Text
- View/download PDF
32. MP-21.18
- Author
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Byung-Oh Kim, Sung Kwang Chung, T.G. Kwon, Heejin Kim, Kyu-Jin Kim, Eun Kyung Yoo, and Yong Bok Park
- Subjects
medicine.medical_specialty ,medicine.anatomical_structure ,Prostate ,business.industry ,Urology ,medicine ,Hyperplasia ,medicine.disease ,business ,Open Prostatectomy ,Resection - Published
- 2006
- Full Text
- View/download PDF
33. The utilisation of Complementary and Alternative Medicine (CAM) among ethnic minorities in South Korea.
- Author
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Jung Hye Hwang, Dong Woon Han, Eun Kyung Yoo, and Woon-Yong Kim
- Subjects
ALTERNATIVE medicine ,CHI-squared test ,FISHER exact test ,HEALTH attitudes ,HEALTH behavior ,RESEARCH methodology ,PSYCHOLOGY of Minorities ,QUESTIONNAIRES ,STATISTICAL sampling ,LOGISTIC regression analysis ,CROSS-sectional method ,DATA analysis software - Abstract
Background Race has been reported to affect the use of complementary and alternative medicine (CAM), but there is very little research on the use of CAM by ethnicity in Korea. This study explores the prevalence of CAM use among ethnic minorities in South Korea. Methods The design is a descriptive and cross-sectional study. A convenience sample of ethnic minorities was recruited from two public healthcare centres in Gyeonggi province. The survey instrument included 37 questions regarding CAM use, factors influencing use of CAM, self-health management, and the socio-demographic profile of study participants. Results Sixty-two percent of study participants reported the use of CAM. Multivitamins (53.3%), acupuncture (48.9%), and traditional Korean herbal medicine (38.9%) were popular CAM modalities in our sample. Other notable CAM modalities included herbal plants, therapeutic massage, and moxibustion therapy. The majority of CAM users (52.2%) received CAM services to treat diseases or as a secondary treatment while receiving conventional care. Having positive perceptions toward the effectiveness of CAM was a major determining factor in CAM use. Conclusions Physicians need to be aware of the fact that many ethnic minorities use CAM therapies. Many CAM users reported that they want doctors to know about their CAM use and have a basic understanding of traditional medicine in their home country. Overcoming language and cultural barriers will help reduce unwanted medical complications. High prevalence of CAM use among ethnic minorities in our study warrants further studies using larger sample population. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
34. Effects of PGC-1α on TNF-α–Induced MCP-1 and VCAM-1 Expression and NF-κB Activation in Human Aortic Smooth Muscle and Endothelial Cells.
- Author
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Hye-Jin Kim, Keun-Gyu Park, Eun-Kyung Yoo, Young-Ho Kim, Yoon-Nyun Kim, Hye-Soon Kim, Hyoung Tae Kim, Joong-Yeol Park, Ki-Up Lee, Won Gu Jang, Jung-Guk Kim, Bo-Wan Kim, and In-Kyu Lee
- Published
- 2007
- Full Text
- View/download PDF
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