• Title/Summary/Keyword: Down-aging

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Epigenetic and Glucocorticoid Receptor-Mediated Regulation of Glutathione Peroxidase 3 in Lung Cancer Cells

  • An, Byung Chull;Jung, Nak-Kyun;Park, Chun Young;Oh, In-Jae;Choi, Yoo-Duk;Park, Jae-Il;Lee, Seung-won
    • Molecules and Cells
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    • v.39 no.8
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    • pp.631-638
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    • 2016
  • Glutathione peroxidase 3 (GPx3), an antioxidant enzyme, acts as a modulator of redox signaling, has immunomodulatory function, and catalyzes the detoxification of reactive oxygen species (ROS). GPx3 has been identified as a tumor suppressor in many cancers. Although hyper-methylation of the GPx3 promoter has been shown to down-regulate its expression, other mechanisms by which GPx3 expression is regulated have not been reported. The aim of this study was to further elucidate the mechanisms of GPx3 regulation. GPx3 gene analysis predicted the presence of ten glucocorticoid response elements (GREs) on the GPx3 gene. This result prompted us to investigate whether GPx3 expression is regulated by the glucocorticoid receptor (GR), which is implicated in tumor response to chemotherapy. The corticosteroid dexamethasone (Dex) was used to examine the possible relationship between GR and GPx3 expression. Dex significantly induced GPx3 expression in H1299, H1650, and H1975 cell lines, which exhibit low levels of GPx3 expression under normal conditions. The results of EMSA and ChIP-PCR suggest that GR binds directly to GRE 6 and 7, both of which are located near the GPx3 promoter. Assessment of GPx3 transcription efficiency using a luciferase reporter system showed that blocking formation of the GR-GRE complexes reduced luciferase activity by 7-8-fold. Suppression of GR expression by siRNA transfection also induced down-regulation of GPx3. These data indicate that GPx3 expression can be regulated independently via epigenetic or GR-mediated mechanisms in lung cancer cells, and suggest that GPx3 could potentiate glucocorticoid (GC)-mediated anti-infla-mmatory signaling in lung cancer cells.

Inhibitory Effects of Methanol Extract of Kaempferia galanga on melanogenesis in B16/F10 Melanoma Cells (B16/F10 흑색종양세포에서 삼내자 메탄올 추출물의 멜라닌 생성에 미치는 억제효과)

  • Yoon, Jung-Won;Han, Jung-Min;Yoon, Hwa-Jung;Ko, Woo-Shin
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.26 no.1
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    • pp.1-18
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    • 2013
  • Objective: Recently the demands for the effective and safe depigmentative and anti-aging agents of the skin have increased due to the medical, pharmaceutical and cosmetic reasons. The purpose of this study is to investigate the MKG(Methanol Extract of Kaempferia galanga) and their dermal bioactivity properties related to cosmeceuticals such as depigmentation. Methods: We assessed inhibitory effects of MKG on melanin production in B16/F10 melanoma cells, on mushroom tyrosinase activity, effects of MKG on the expression tyrosinase, TRP-1, TRP-2, GSK-$3{\beta}$, CREB, MITF in B16/F10 melanoma cells without cytotoxicity range. Cell viability was measured by MTT assay and tyrosinase activity was assessed using by DOPA staining, western-blot analysis. We measured inhibition of melanin synthesis and tyrosinase activity by down-regulation of melanogenic enzyme expressions in ${\alpha}$-MSH induced melanogenesis B16/F10 melanoma cells. Results: MKG inhibited tyrosinase-activity, total melanin contents and dendrite out-growth. MKG inhibited melanogenesis by down-regulation of tyorsinase, TRP-1, TRP-2, CREB, and MITF in B16/F10 cells. The treatment with MKG at the 12.5, $25{\mu}g/ml$ level significantly inhibited the melanin synthesis induced ${\alpha}$-MSH in B16/F10 melanoma cells compared with untreated control. Conclusion: These results suggest that MKG inhibit melanin biosynthesis which is involved in hyper-pigmentation. So MKG is considered to be used as a whitening components reducing cytotoxicity.

Characterization of ERp29 and ADP-Ribosylation Factor 5 Interaction (ERp29와 ADP-ribosylation factor 5의 결합특성)

  • Kwon, Ki-Sang;Seog, Dae-Hyun;Kim, Seung-Whan;Yu, Kweon;Kwon, O-Yu
    • Journal of Life Science
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    • v.21 no.4
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    • pp.613-615
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    • 2011
  • ERp29 is a endoplasmic reticulum (ER) lumenal resident protein that shows sequence similarity to the protein disulfide isomerase family. Its biological function is thought to play a role in the processing of secretory proteins within the ER, possibly by participating in the folding of proteins in the ER. Although some data on ERp29 have been reported, its normal functions are still unclear. To gain insights into the function of ERp29, we identified ARF5 protein as a protein that interacts with ERp29 using yeast two-hybrid screening and GST pull-down assay. Interaction between ERp29 and ARF5 was detected under normal cell conditions but not under ER stress conditions. This result may provide a clue for understanding ERp29 biological functions.

Development of Non-Motorized Lifting Chair For the Elderly (고령자를 위한 무동력 기립보조의자 개발)

  • Kim, Hyeon Jun;Yeo, Hyeon Jin;Kim, Sung Soo;Chang, Sung Ho;Lee, Sang Ho;Bae, Ik Soon
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.38 no.4
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    • pp.226-232
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    • 2015
  • The aging of Korea is rapidly advancing in an unprecedented rate in the world. Indoor and outdoor safety accidents involving the elderly frequently occur, with elderly population increasing. Because the physical strength of elderly is decreased, it is necessary to develop devices that aid the everyday life of the elderly to prevent safety accidents. Among many activities, the motions of standing from and sitting on a chair require much physical strength from particular body parts, which causes an overload for particular body parts. To the elderly the repeating motion of standing from and sitting down on a chair is burdensome, because they do not have enough physical strength compare to young persons. As a result the elderly could be injured or falling during standing or sitting. Therefore, the development of a lift chair that considers the problems mentioned above is necessary to prevent the safety accidents of the elderly. The study designed a non-motorized lift chair that comfortably aids the standing and sitting down motion for the use of the elderly by reflecting the anthropometric data of the Korean elderly over 65 years old. Also the design was implemented to smoothly aid the standing motion by considering the knee angle of the elderly when standing. Because the regained strength to stand from a chair is depend on the knee angle. Unlike existing lift devices, this device utilizes a tilting mechanism that does not use electric power so that the product could be composed inexpensively than existing chairs released in the market.

Cilostazol Promotes the Migration of Brain Microvascular Endothelial Cells (Cilostazol에 의한 뇌혈관내피세포의 세포이동 증진 효과연구)

  • Lee, Sae-Won;Park, Jung Hwa;Shin, Hwa Kyoung
    • Journal of Life Science
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    • v.26 no.12
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    • pp.1367-1375
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    • 2016
  • Cilostazol is known to be a selective inhibitor of phosphodiesterase III and is generally used to treat stroke. Our previous findings showed that cilostazol enhanced capillary density through angiogenesis after focal cerebral ischemia. Angiogenesis is an important physiological process for promoting revascularization to overcome tissue ischemia. It is a multistep process consisting of endothelial cell proliferation, migration, and tubular structure formation. Here, we examined the modulatory effect of cilostazol at each step of the angiogenic mechanism by using human brain microvascular endothelial cells (HBMECs). We found that cilostazol increased the migration of HBMECs in a dose-dependent manner. However, it did not enhance HBMEC proliferation and capillary-like tube formation. We used a cDNA microarray to analyze the mechanisms of cilostazol in cell migration. We picked five candidate genes that were potentially related to cell migration, and we confirmed the gene expression levels by real-time PCR. The genes phosphoserine aminotransferase 1 (PSAT1) and CCAAT/enhancer binding protein ${\beta}$ ($C/EBP{\beta}$) were up-regulated. The genes tissue factor pathway inhibitor 2 (TFPI2), retinoic acid receptor responder 1 (RARRES1), and RARRES3 were down-regulated. Our observations suggest that cilostazol can promote angiogenesis by promoting endothelial migration. Understanding the cilostazol-modulated regulatory mechanisms in brain endothelial cells may help stimulate blood vessel formation for the treatment of ischemic diseases.

Evaluation of Dynamic Modulus based on Aged Asphalt Binder (아스팔트 바인더의 노화특성을 고려한 동탄성계수 평가)

  • Lee, Kwan-Ho;Cho, Kyung-Rae;Lee, Byung-Sik;Song, Yong-Seon
    • Journal of the Korean Society of Hazard Mitigation
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    • v.8 no.3
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    • pp.51-58
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    • 2008
  • Development of a new design guide which is based on empirical-mechanistic concept for pavement design is in action. It is called AASHTO 2002 Design Guide in USA and the KPRP(Korean Pavement Research Project) in Korea. The material characteristic of hot mix asphalt is a key role in the design guide. Therefore it is urgent to get a proper materials database, especially the dynamic modulus of hot mix asphalt. In this research, dynamic modulus test, which is based on aged asphalt binder, has been carried out and proposed the predicted equation of dynamic modulus. Nine different hot mix asphalt with three different asphalt binder have been used for the dynamic modulus test. Short-term aging, which is covers the time for the production of asphalt plant, transportation, lay-down, and compaction, can be simulated at $135^{\circ}C$ with 2 hour curing. Long-term aging has been carried out for a performance period of asphalt pavement. The dynamic modulus of asphalt pavement increases with aging time. As the nominal aggregate size increases, the change of dynamic modulus is not big.

Induction of Muscle Atrophy by Dexamethasone and Hydrogen Peroxide in Differentiated C2C12 Myotubes (C2C12 근관세포에서 dexamethasone 및 hydrogen peroxide에 의한 근위축 유도)

  • Park, Cheol;Jeong, Jin-Woo;Choi, Yung Hyun
    • Journal of Life Science
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    • v.27 no.12
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    • pp.1479-1485
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    • 2017
  • Muscle atrophy due to aging, starvation, and various chronic diseases leads to a decrease in muscle fiber area and density due to reduced muscle protein synthesis and increased protein breakdown. This study investigated the effect of dexamethasone and hydrogen peroxide on the induction of muscle atrophy and expression of atrophy-related genes in differentiated C2C12 myotubes. C2C12 myoblasts were differentiated into myotubes in differentiation medium. During myoblast differentiation, muscle-specific transcription factors, such as myogenin, and MyoD expression increased. Differentiated C2C12 myotubes exposed to noncytotoxic levels of dexamethasone and hydrogen peroxide showed a decrease in myotube diameter, which was associated with up-regulation of muscle-specific ubiquitin ligases, such as muscle atrophy F-box (MAFbx)/atrogin-1 and muscle RING finger-1 (MuRF1), and down-regulation of myogenin and MyoD. These results demonstrated that dexamethasone and hydrogen peroxide induced atrophy through regulation of muscle-specific ubiquitin ligases and muscle-specific transcription factors in C2C12 myotubes. In this study, we confirmed the process of differentiation of C2C12 myoblasts into myotubes in in vitro experiments in the presence of atrophy. This muscle atrophy model of C2C12 cells induced by dexamethasone or hydrogen peroxide seems suited to studies of the mechanism of muscle atrophy suppression and to exploit the experiment for excavating new muscle atrophy.

Induction of Apoptotic Cell Death by Cordycepin, an Active Component of the Fungus Cordyceps militaris, in AGS Human Gastric Cancer Cells (동충하초 유래 cordycepin에 의한 AGS 인체 위암세포의 apoptosis 유발)

  • Lee, Hye Hyeon;Jeong, Jin-Woo;Choi, Yung Hyun
    • Journal of Life Science
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    • v.26 no.7
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    • pp.847-854
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    • 2016
  • Cordycepin, a derivative of the nucleoside adenosine, is one of the active components extracted from fungi of genus Cordyceps, and has been shown to have many pharmacological activities. In this study, we investigated the effects of cordycepin on proliferation and apoptosis of human gastric cancer AGS cells, and its possible mechanism of action. Treatment of cordycepin resulted in significant decrease in cell viability of AGS cells in a concentration-dependent manner. A concentration-dependent apoptotic cell death was also measured by agarose gel electrophoresis and flow cytometery analysis. Molecular mechanistic studies of apoptosis unraveled cordycepin treatment resulted in an enhanced expression of tumor necrosis factor-related apoptosis-inducing ligand, death receptor 5 and Fas ligand. Furthermore, up-regulation of pro-apoptotic Bax, and down-regulation of anti-apoptotic Bcl-2 and Bcl-xL expression were also observed in cordycepin-treated AGS cells. These were followed by activation of caspases (caspase-9, -8 and -3), subsequently leading to poly (ADP-ribose) polymerase cleavage. Taken together, these findings indicate that cordycepin induces apoptosis in AGS cells through regulation of multiple apoptotic pathways, including death receptor and mitochondria. Although further mechanical studies are needed, our results revealed that cordycepin can be regarded as a new effective and chemopreventive compound for human gastric cancer treatment.

The Influence of Vocal Cords and Intensity by Hemodialysis in End Stage Renal Disease (말기 신부전 환자에서 혈액투석 치료가 성대 및 강도의 변화에 미치는 영향)

  • Kim, Bong-Hyun;Cho, Dong-Uk;Kang, Eung-Taek
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.7B
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    • pp.1066-1072
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    • 2010
  • Kidney diseases rates in modern Korean society, which is entering an aging society, are growing. These diseases diagnosed at early stage can be cured with the drug or dietary treatment. If, however, at worsening stage, kidney dialysis or transplant is needed. In this context, we analyzed the relationship between kidney and voice by measuring and analyzing the changing rate of the vocal chord and intensity according to hemodialysis. For this, we collected voice samples before and after hemodialysis, and compared and analyzed them through application of vocal analytical element. Namely, based on oriental medical diagnosis theory that voice is quieted down when kidney is abnormal, we collected voice samples before and after hemodialysis, and applied trembling and intensity analysis of vocal chord.

Effects of Theraband Exercise Programs on Strength, Balance and Proprioception in Elderly (세라밴드를 이용한 운동프로그램이 노인의 근력, 균형, 고유수용성감각에 미치는 영향)

  • Lee, Dongjin
    • Journal of The Korean Society of Integrative Medicine
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    • v.2 no.4
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    • pp.1-8
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    • 2014
  • Purpose: The purpose of this study was to recognize the importance of balance in order to minimize daily living restrictions and to prevent falls due to aging, and develop an eight-week theraband exercise program to benefit the elderly. Method: A total of 20 elderly participants were divided into two groups. Group A used warm-up and finishing exercises for eight weeks including stretching and rhythm exercises conducted in a theraband exercise. Group B performed no exercises. Both A and B groups at weeks 1, weeks 4, weeks 8 were measured for deltoid and quadriceps femoris strength, balance and proprioception. Result: There was a significant difference in deltoid and quadriceps femoris muscle strength, balance and proprioception between Group A and Group B(p<0.05). Conclusion: The results of this study show that theraband exercises are thought to be able to contribute to the promotion of deltoid and quadriceps femoris muscle strength, balance and proprioception. It also contributes to minimize activity of daily living restrictions and prevent fall down in elderly. However in this study, generalization has been limited because of exercise duration, limited number of experiments and intensity modulated of theraband.