Prostaglandin A₂-induced Apoptosis is Not Inhibited by Heme Oygenase-1 in U2OS Cells

Kyoung-Won Ko(고경원),Sun-Young Lee(이선영),Ji-Hyun Ahn(안지현),Jaetaek Kim(김재택),In-Kyung Kim(김인경),Ho-Shik Kim(김호식) 한국생명과학회 2008 생명과학회지 Vol.18 No.11

Prostaglandin A₂ (PGA₂)는 사람 골육종 세포인 U2OS 세포주에서 apoptosis와 heme oxygenase (HO)-1의 발현을 함께 유도하였다. PGA₂에 의한 apoptosis는 HO-1의 과도한 발현이나 HO-1에 대한 small interfering RNA에 의한 발현저하에 의하여 변동되지 않았으나 H₂O₂에 의한 세포사망은 HO-1의 발현 수준에 반비례하여 변동되었다. 또한 thiol antioxidant인 N-acetyl-L-cysteine (NAC)은 PGA₂에 의한 세포사망과 HO-1의 발현 증가를 모두 차단하였지만, non-thiol antioxidant인 butylated hydroxyanisole (BHA)과 ascorbic acid는 세포사망과 HO-1의 발현 유도를 차단하지 않았다. 이와 같은 결과들은 PGA₂는 산화성 손상에 의해서가 아니라 PGA₂의 thiol-reactivity에 의하여 apoptosis와 HO-1의 발현을 유도하며, HO-1의 발현은 PGA₂에 의한 apoptosis와는 독립적인 현상이거나 기능적으로 apoptosis 유도의 하부에 위치하고 apoptosis의 진행에는 기여하지 않을 것이라는 것을 시사해 준다. Prostaglandin A₂ (PGA₂), one of cyclopentenone PGs, induced both apoptosis and heme oxygenase (HO)-1 expression in U2OS cells. PGA₂-induced apoptosis was not perturbed by either over-expression or knock-down of HO-1, whereas H₂O₂-induced cell death was inversely modulated by the expression level of HO-1. In addition, N-acetyl-L-cysteine (NAC), a thiol antioxidant, blocked both apoptosis and HO-1 expression induced by PGA₂. But, non-thiol antioxidants like butylated hydorxyanisole (BHA) and ascorbic acid did not block either apoptosis or HO-1-induction. Taken together, these results suggest that PGA₂ induces both apoptosis and HO-1 expression, which are critically related to the thiol-reactivity of PGA₂, but not oxidative stress, and HO-1 expression may be independent or functionally located downstream of apoptosis by PGA₂ without contribution to apoptosis progression.

Improvement of adhesion properties of glass prepared using SiC‑deposited graphite mold via low‑temperature chemical vapor deposition

Kyoung‑Ho Kim,Kuk‑Jin Hwang,Heesoo Lee,Seong‑Min Jeong,이명현,배시영 한국세라믹학회 2020 한국세라믹학회지 Vol.57 No.1

Compression glass molding is a promising technique for mass production of near net-shaped, high-precision, and low-cost optical glass elements. However, the glass molding process causes the damage of glass and the mold during demolding because of the chemical or physical adhesion of the glass to the mold. To overcome this limitation, graphite molds are used owing to their good lubrication and easy machining. However, graphite materials show rapid oxidation at high temperatures in the presence of oxygen. Therefore, in this study, a thin SiC coating layer was deposited on the graphite mold using the chemical vapor deposition (CVD) method to utilize the lubrication properties of graphite and the anti-oxidation properties of SiC. The specimen obtained using the low-temperature CVD method showed high carbon content and good lubrication properties than that obtained using the high-temperature CVD method.

Phosphodiesterase inhibitor improves renal tubulointerstitial Hypoxia of the Diabetic rat Kidney

( Hui Kyoung Sun ),( Yun Mi Lee ),( Kum Hyun Han ),( Han Seong Kim ),( Seon Ho Ahn ),( Sang Youb Han ) 대한내과학회 2012 The Korean Journal of Internal Medicine Vol.27 No.2

Background/Aims: Renal hypoxia is involved in the pathogenesis of diabetic nephropathy. Pentoxifyllin (PTX), a nonselective phosphodiesterase inhibitor, is used to attenuate peripheral vascular diseases. To determine whether PTX can improve renal hypoxia, we investigated its effect in the streptozocin (STZ)-induced diabetic kidney. Methods: PTX (40 mg/kg, PO) was administered to STZ-induced diabetic rats for 8 weeks. To determine tissue hypoxia, we examined hypoxic inducible factor-1α (HIF-1α), heme oxygenase-1 (HO-1), vascular endothelial growth factor (VEGF), and glucose transporter-1 (GLUT-1) levels. We also tested the effect of PTX on HIF-1α in renal tubule cells. Results: PTX reduced the increased protein creatinine ratio in diabetic rats at 8 weeks. HIF-1α, VEGF, and GLUT-1 mRNA expression increased significantly, and the expression of HO-1 also tended to increase in diabetic rats. PTX significantly decreased mRNA expression of HIF-1α and VEGF at 4 and 8 weeks, and decreased HO-1 and GLUT-1 at 4 weeks. The expression of HIF-1α protein was significantly increased at 4 and 8 weeks in tubules in the diabetic rat kidney. PTX tended to decrease HIF-1α protein expression at 8 weeks. To examine whether PTX had a direct effect on renal tubules, normal rat kidney cells were stimulated with CoCl2 (100 μM), which enhanced HIF-1α mRNA and protein levels under low glucose conditions (5.5 mM). Their expressions were similar even after high glucose (30 mM) treatment. PTX had no effect on HIF-1α expression. Conclusions: PTX attenuates tubular hypoxia in the diabetic kidney.

중량조끼를 이용한 부하보행훈련이 뇌졸중 환자의 정적균형과 동적균형에 미치는 영향

신승호,이경진,송창호 대구대학교 특수교육재활과학연구소 2011 특수교육재활과학연구 Vol.50 No.3

The present study examined the effects of gait training with Additional weight in patients with chronic stroke. This study purposed to propose the effectiveness through comparative analysis of the effects of gait training with additional weight and gait training with non-additional weight on static balance and dynamic balance in patients with chronic stroke. The study was conducted at a hospital in Kyoung-ki do and the subjects were divided randomly into two groups: additional weight group(n =12), non-additional weight group(n =8). Both of groups received general physical therapy for 30min in 1 session, 5 sessions per a week during six months. Experimental group practiced gait training with additional weight for 20 min a day, 3 days per a week during 6 months and control group practised gait training with non- additional weight for 20min a day, 3 days per a week during 6 month. Static balance and dynamic balance were tested and analysed before and after the 6 weeks gait training, and the result were as follows. Static balance and dynamic balance is increased significantly in both of groups except for mediolateral sway(p < .05). the result of additioanl weight group showed more significant increase than the result of non-additional weight group (p < .05). According to the result of this study, as gait training with additional weight improves dynamic balance in patients with chronic stroke, this gait training method is effective and suitable for patients with chronic stroke to increase the ability of functional performance. 본 연구는 만성 뇌졸중 환자 20명을 대상으로 부하자극을 이용한 보행훈련이 만성 뇌졸중 환자의 정적균형 및 동적균형에 미치는 효과를 규명하고자 부하자극보행군 12명과 무부하자극보행군 8명으로 나누어 시행하였다. 부하자극보행군과 무부하자극보행군 모두 동일하게 1회 30분씩 주 5회 일반적 물리치료를 시행하였으며, 부하자극보행군에게 부하자극을 적용한 보행훈련을 1회 20분, 주 3회 실시하였고, 무부하자극보행군에게 부하자극을 적용하지 않은 보행훈련을 1회 20분, 주 3회 실시하였다. 훈련은 6주간 시행되었고 훈련 전ㆍ후에 정적균형과 동적균형을 측정하였으며 다음과 같은 결과를 얻었다. 부하자극보행군은 정적균형은 훈련 전보다 훈련 후에 유의하게 증가하였고(p < .05), 무부하자극보행군은 좌우동요를 제외하고 훈련 전보다 훈련 후에 유의하게 증가하였다(p < .05), 두 군의 전후 변화량의 유의한 차이를 보이지 않았다. 두 군 모두 동적균형은 훈련 전보다 훈련 후에 유의하게 증가하였고(p < .05), 부하자극보행군은 무부하자극보행군에 비해 유의한 증가를 보였다(p < .05). 위의 결과를 바탕으로, 부하자극을 적용한 보행훈련이 만성 뇌졸중 환자의 동적균형능력을 향상시키는 운동방법으로 뇌졸중 환자의 보행 재활에 활용할 수 있을 것으로 생각한다. 또한 정적균형을 향상시키는 방법으로는 적절하지 못하다고 생각한다.

경기 지역 대기 오염 농도의 시간 변동성과 관련된 종관 기상 상태의 전개

임규호(Gyu-Ho Lim),김경아(Kyoung-A Kim) 한국기상학회 1996 Asia-Pacific Journal of Atmospheric Sciences Vol.32 No.1

대학 운동선수의 정체성과 성취목표가 수행전략에 미치는 효과

유경호(Yoo, Kyoung-Ho),장세용  (Jang, Se-Yong),최경아(Choi, Kyung-A),김승철(Kim, Seung-Chul) 한국체육과학회 2013 한국체육과학회지 Vol.22 No.1

The aim of this study was to examine the effect of college athletes’ achievement goal and identity on performance strategy. The participants of this study were 300 of college athletes in Seoul and Kyoung-gi area. For the analysis of data, exploratory factor analysis, multivariate analysis of variance (MANOVA), two-way ANOVA, and hierarchical multiple regression were used. The results were as follows. First, the significantly important predictor variables of athletic identity were condition control, emotion control, self-talk, and imegery/goal setting predictor variable. Condition control, tense relaxation, and self-talk were significantly important predictor variables of achievement goal. Condition control, emotion control, and imegery/goal setting were significantly important predictor variables of athletic career, skillfulness, and performance avoid goal Two, athletic identity, and performance approach goal interacted and affected self-talk for the athletes among two-way, and three-way interaction variables.

경기 지역 농경지 하부로의 해수 침투에 관한 지구물리 및 지구화학적 연구

이상호 ( Sang Ho Lee ),김경웅 ( Kyoung Woong Kim ),이상규 ( Sang Kyu Lee ) 한국지구물리·물리탐사학회 1999 지구물리와 물리탐사 Vol.2 No.2

Effects of Jeju Water Containing Vanadium on Antioxidant Enzymes in vitro

Areum Daseul Kim,Kyoung Ah Kang,Rui Zhang,Mei Jing Piao,김석만,지영흔,Nam Ho Lee,Ho Jin You,고경수,현진원 대한암예방학회 2010 Journal of cancer prevention Vol.15 No.4

scavenging of reactive oxygen species (ROS). In the present study, the aim was to examine the antioxidant effect of Jeju water containing vanadium (S3, 26.0±2.0 μg/l) in terms of antioxidant enzymes in vitro. Human Chang liver cells were incubated for 10 passages in media prepared with either deionized distilled water (DDW) or S3. S3 increased activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and heme oxygenase-1 (HO-1) compared to DDW. S3 also increased the level of reduced glutathione (GSH) shown by colorimetric assay and by high-resolution magic angle spinning nuclear magnetic resonance (HR-MAS NMR) spectroscopy. These results suggest that vanadium-containing Jeju water (S3) produces antioxidant effect in vitro by enhancing antioxidant enzyme activities. (Cancer Prev Res 15, 262-267, 2010)

Morin exerts cytoprotective effects against oxidative stress in C2C12 myoblasts via the upregulation of Nrf2-dependent HO-1 expression and the activation of the ERK pathway

Lee, Moon Hee,Han, Min Ho,Lee, Dae-Sung,Park, Cheol,Hong, Su-Hyun,Kim, Gi-Young,Hong, Sang Hoon,Song, Kyoung Seob,Choi, Il-Whan,Cha, Hee-Jae,Choi, Yung Hyun UNKNOWN 2017 INTERNATIONAL JOURNAL OF MOLECULAR MEDICINE Vol.39 No.2

<P>In the present study, we investigated the cytoprotective efficacy of morin, a natural flavonoid, against oxidative stress and elucidated the underlying mechanisms in C2C12 myoblasts. Our results indicated that morin treatment prior to hydrogen peroxide (H2O2) exposure significantly increased cell viability and prevented the generation of reactive oxygen species. H2O2-induced comet-like DNA formation and gamma H2AX phosphorylation were also markedly suppressed by morin with a parallel inhibition of apoptosis in C2C12 myoblasts, suggesting that morin prevented H2O2-induced cellular DNA damage. Furthermore, morin markedly enhanced the expression of heme oxygenase-1 (HO-1) associated with the induction and phosphorylation of nuclear factor-erythroid 2-related factor 2 (Nrf2) and the inhibition of Kelch-like ECH-associated protein 1 (Keapl) expression. Notably, these events were eliminated by transient transfection with Nrf2-specific small interfering RNA. Additional experiments demonstrated that the activation of the Nrf2/HO-1 pathway by morin was mediated by the extracellular signal-regulated kinase (ERK) signaling cascade. This phenomenon was confirmed with suppressed Nrf2 phosphorylation and consequently diminished HO-1 expression in cells treated with a pharmacological inhibitor of ERK. Collectively, these results demonstrated that morin augments the cellular antioxidant defense capacity through the activation of Nrf2/HO-1 signaling, which involves the activation of the ERK pathway, thereby protecting C2C12 myoblasts from H2O2,-induced oxidative cytotoxicity.</P>

조구등(釣鉤藤)의 4-VO로 유발한 흰쥐뇌허혈에 대한 신경방어효과

李仁煥,林康鉉,李鍾錫,石庚浩,安德均,朴虎君,김頀哲 대한본초학회 1999 大韓本草學會誌 Vol.14 No.2

Uncariae Ramulus et Uncus(UR, ???) has sweet in flavour and slightly cold in property, acting on the liver and pericardium channels. This drug was described in a medical classic as having the ability to remove "heat", check hyperfunction of the liver and relieve dizziness, tremors, and convulsion, and subdue "endogenous wind". So this study was planned to check the neuroprotective effect of UR on the global ischemia induced by 4-vessel occlusion in Wistar rats. and UR extract was lyophilized after extraction with 70% methanol. We induced 4-vessel occlusion for 10 minutes and reperfused again. The number of CA1 pyramidal neurons were counted after 7 days of reperfusion under the cresyl violet staining. In 4-VO ischemia model, UR showed significantly neuroprotective effects(1,000 and 500 ㎎/㎏ of UR extracts, p<0.05) compared with control group. Each neuroprotective ratio was about 23.0%, 19.0% respectively. Consequently, Uncariae Ramulus et Uncus has neuroprotective effects on the global ischermia induced by 4-vessel occlusion in Wistar rats. So we expect that Uncariae Ramulus et Uncus can be used as a drug for neurodegenerative disease.