PGA2-induced expression of HO-1 is mediated by transcriptional upregulation of Nrf2

Sang-sun Lee,Yun-Jeong Choe,Hyein Lee,Sun-Young Lee,Ho-Shik Kim 대한독성 유전단백체 학회 2019 Molecular & cellular toxicology Vol.15 No.2

Backgrounds: Prostaglandin (PG) A2 reportedly stimulated expression of heme oxygenase (HO)-1 at the level of transcription via the activation of p38MAPK. Details of the mechanism, however, have not been provided, and this includes identification of the transcription factors responsible for PGA2-induced HO-1 expression. Herein is described an analysis of the role of nuclear factor erythroid 2 related factor 2 (Nrf2) and how PGA2 increases the activity of Nrf2 during PGA2-induced HO-1 expression. Methods: Expressions of HO-1 and Nrf2 were analyzed at the levels of both mRNA and protein. Nrf2 siRNA, SB203580, an inhibitor of p38MAPK, and scavengers of reactive oxygen species (ROS) were used to identify the effects of Nrf2, p38MAPK and ROS on PGA2-induced HO-1 expression. Results: Although SB203580 suppressed PGA2-induced HO-1 expression, genetic activation of p38MAPK could not stimulate the transcription of HO-1. Cycloheximide (CHX), an inhibitor of protein translation, almost completely prevented PGA2-induced increase of HO-1 transcription, but it did not prevent the phosphorylation of p38MAPK, which suggests that both de novo protein synthesis and p38MAPK activity are required to induce the transcription of HO-1 in response to PGA2 treatment. In addition, PGA2 increased the level of both Nrf2 mRNA and protein in a dose-dependent manner. Knockdown of Nrf2 using small interfering RNA (siRNA) suppressed PGA2-induced HO-1 expression. The PGA2-induced transcription of Nrf2 was prevented by ROS scavengers such as n-acetyl-l-cysteine and tempol but not CHX. Furthermore, siRNA against p38MAPK did not change the level of nuclear Nrf2 protein. Conclusion: These findings suggest that PGA2 induces HO-1 transcription via an increase in Nrf2 protein, the transcription of which is initiated by an accumulation of ROS that is independent of the p38MAPK activation pathway.

PGA2 induces the expression of HO-1 by activating p53 in HCT116 cells

Hyein Lee,Sang-Sun Lee,Ji-Young Park,Yun-Jeong Choe,이선영,Ho-Shik Kim,H.-S. Kim 대한독성 유전단백체 학회 2017 Molecular & cellular toxicology Vol.13 No.2

Prostaglandin (PG) A2 which is a cytotoxic PG, was reported to induce the expression of heme oxygenase (HO)-1 via activation of p38MAPK to keep U2OS cells from cell cycle arrest in G2M phase. The expression of HO-1 is primarily regulated at the level of transcription. But the transcription factors that are responsible for PGA2-induced HO-1 expression were not clarified yet. Here, we report that PGA2-induced transcription of HO-1 is mediated by p53, a tumor suppressive transcription factor. In HCT116 cells, PGA2 treatment led to the phosphorylation of p53 and an increase of p21WAF1 transcription as well as the activation of HO-1 transcription. Knocking p53 down via RNA interference or inhibiting the p53’s transcriptional activity by pifithrin-α treatment led to suppression of the increase in the level of both HO-1 expression and activity of HO-1 promoter. Pretreatment of NU- 7441, a chemical inhibitor of DNA-activated protein kinase (DNA-PK), prevented both the PGA2-induced phosphorylation of p53 and an increase of HO-1 transcription. In addition, N-acetyl-l-cysteine, a scavenger of reactive oxygen species (ROS), also mimicked the effect of NU-7441 on the PGA2-induced activation of p53 and HO-1 transcription. Collectively, these results suggest that PGA2 induces the expression of HO-1 via activation of p53, which is mediated by the ROSDNA- PK pathway.

N-acetyl cysteine inhibits H2O2-mediated reduction in the mineralization of MC3T3-E1 cells by down-regulating Nrf2/HO-1 pathway

( Daewoo Lee ),( Sung Ho Kook ),( Hyeok Ji ),( Seung Ah Lee ),( Ki Choon Choi ),( Kyung Yeol Lee ),( Jeong Chae Lee ) 생화학분자생물학회(구 한국생화학분자생물학회) 2015 BMB Reports Vol.48 No.11

There are controversial findings regarding the roles of nuclear factor (erythroid-derived 2)-like 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway on bone metabolism under oxidative stress. We investigated how Nrf2/HO-1 pathway affects osteoblast differentiation of MC3T3-E1 cells in response to hydrogen peroxide (H2O2), N-acetyl cysteine (NAC), or both. Exposing the cells to H2O2 decreased the alkaline phosphatase activity, calcium accumulation, and expression of osteoblast markers, such as osteocalcin and runt-related transcription factor-2. In contrast, H2O2 treatment increased the expression of Nrf2 and HO-1 in the cells. Treatment with hemin, a chemical HO-1 inducer, mimicked the inhibitory effect of H2O2 on osteoblast differentiation by increasing the HO-1 expression and decreasing the osteogenic marker genes. Pretreatment with NAC restored all changes induced by H2O2 to near normal levels in the cells. Collectively, our findings suggest that H2O2-mediated activation of Nrf2/HO-1 pathway negatively regulates the osteoblast differentiation, which is inhibited by NAC. [BMB Reports 2015; 48(11): 636-641]

PGA2-induced HO-1 attenuates G2M arrest by modulating GADD45α expression

Yun-Jeong Choe,고경원,Hyein Lee,이선영,Byung-Chul Kim,Ho-Shik Kim,Ho-Shik Kim 대한독성 유전단백체 학회 2015 Molecular & cellular toxicology Vol.11 No.4

Prostaglandin (PG) A2, a cyclopentenone PG, arrested the growth of U2OS cells in the G2M phase. While inducing G2M arrest, PGA2 increased the expression of heme oxygenase-1 (HO-1) at the level of transcription along with the accumulation of ROS and the activation of MAPKs including JNK, p38MAPK, and ERK1/2. Among the MAPKs, the inhibition of p38MAPK by a specific chemical inhibitor SB203580, or by RNA interference, but not JNK or ERK1/2, attenuated the PGA2-induced transcription of HO-1. Nacetylcysteine (NAC), a ROS scavenger, prevented PGA2-induced G2M arrest, p38MAPK activation and transcriptional induction of HO-1. PGA2 also stimulated GADD45α expression at the level of transcription, and the knockdown of GADD45α repressed PGA2- induced G2M arrest. Finally, the knockdown of the HO-1 protein elevated PGA2-induced GADD45α expression as well as G2M arrest. Collectively, these results suggest that PGA2 causes an increase in ROS accumulation which initiates both HO-1 transcription via p38MAPK, and G2M arrest via GADD45α transcription, and HO-1 attenuates G2M arrest by modulating the expression of GADD45α.

Nutlin-3 induces HO-1 expression by activating JNK in a transcription-independent manner of p53

CHOE, YUN-JEONG,LEE, SUN-YOUNG,KO, KYUNG WON,SHIN, SEOK JOON,KIM, HO-SHIK Spandidos Publications 2014 International journal of oncology Vol.44 No.3

A recent study reported that p53 can induce HO-1 by directly binding to the putative p53 responsive element in the HO-1 promoter. In this study, we report that nutlin-3, a small molecule antagonist of HDM2, induces the transcription of HO-1 in a transcription-independent manner of p53. Nutlin-3 induced HO-1 expression at the level of transcription in human cancer cells such as U2OS and RKO cells. This induction of HO-1 did not occur in SAOS cells in which p53 was mutated and was prevented by knocking down the p53 protein using p53 siRNA transfection, but not by PFT-alpha, an inhibitor of the transcriptional activity of p53. Accompanying HO-1 expression, nutlin-3 stimulated the accumulation of ROS and the phosphorylation of MAPKs such as JNK, p38 MAPK and ERK1/2. Nutlin-3-induced HO-1 expression was suppressed by TEMPO, a ROS scavenger, and chemical inhibitors of JNK and p38 MAPK but not ERK1/2. In addition, nutlin-3-induced phosphorylation of JNK but not p38 MAPK was inhibited by TEMPO. Notably, the levels of nutlin-3-induced ROS were correlated with the mitochondrial translocation of p53 and this induction was prevented by PFT-beta, an inhibitor of the mitochondrial translocation of p53. Consistent with the effect of the ROS scavenger and MAPK inhibitors, PFT-beta reduced HO-1 expression and the phosphorylation of JNK induced by nutlin-3. In the experiments of analyzing cell death, the knockdown of HO-1 augmented nutlin-3-induced apoptosis. Collectively, these results suggest that nutlin-3 induces HO-1 expression via the activation of both JNK which is dependent on ROS generated by p53 translocated to the mitochondria and p38 MAPK which appears to be stimulated by a ROS-independent mechanism, and this HO-1 induction may inhibit nutlin-3-induced apoptosis, constituting a negative feedback loop of p53-induced apoptosis.

KAERI 부지 주변의 환경선량 측정을 위한 온라인 감마선량 감시시스템

이정호,박두원,이원윤,이현덕,최용호,김삼랑,홍광희,이창우 대한방사선 방어학회 1994 방사선방어학회지 Vol.19 No.2

환경감마선량 변동을 감시하기 위해 한국원자력연구소 부지 주변에 온라인 감마선량 감시망을 구성하였다. 모니터링 포스트에 설치된 전리함 검출기에 의해 측정된 자료는 무선전송방식으로 중앙통제소에 전송되어 실시간으로 감시된다. 무선전송 방식은 자료의 전송, 처리 및 자자에 신뢰도가 높고 경제적이었다. 감시시스템은 급격한 선량증가시 조기경보체제와 연결할 수 있게 하였다. On-line gamma monitoring system around KSERI-site was set up to monitor the radiation fluctuations in environment. Data on gamma exposure rates measured by the ionication chamber in the monitoring posts are transmitted to a computer of central control station with radio telemetry transmission and reliable on handing and storing of data. This monitroing system can triger an early warning system in the event of abnormal radiation levels.

병원급식 체계에 관한 조사 연구

이정윤,서정숙,방병호,정은자,강남이,이진영 서울보건대학 1995 서울보건대학 부설 병원경영연구소 논문집 Vol.1 No.1

This study was conducted to evaluate the hospital foodservice management practices in Seoul and to suggest the guideline for the effective foodservice management. Questionnaire survey method were used in this study. Questionnaire were administered to dietitians in twenty hospitals. Data were analyzed for frequency, percentage, χ^(2)-test, and one-way ANOVA using SAS PC Package program. The results were summerized as follows : The number of dietition were less than the required number for efficient foodservice. Centralized foodservice method was adopted in most hospitals and conventional foodservice system was taken in all the hospitals. The space of a kitchen and a dining room were confined and sanitary facilities and working condition revealed problems. Equipped facilities in surveyed foodservice operations were assessed as the insufficient condition, especially, efficient facilities such as a cutting machine were scarecely make up.

Influence of Phase Composition in TiAlSiN Hard Coatings on the Evolution of Structure and Mechanical Properties

Jeong‑Han Lee,Ik‑Hyun Oh,Jun‑Ho Jang,Ju‑Hun Kim,Sung‑Kil Hong,Hyun‑Kuk Park 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.3

The aim of this study is to investigate the structural evolution and mechanical properties of TiAlSiN coatings when processedby the arc ion plating method. To form a hard coating, Ti, Al, and Si powders were mechanically alloyed by planetary ballmilling; the powders were then densely compacted during a rapid sintering process into a ternary system coating, i.e. TiAlSi. The evolution of the structural phase from a powder to a compact material is dominated considerably by phase states suchas a supersaturated solid solution or intermetallic compounds. In the case of coating layers, the factors that determine thestructural evolution are associated with the phase stability of the nano-crystalline structure that in turn is associated withthe Ti/Al composition ratio. Motivated by this, we performed experiments to investigate the distribution of microstructures;the material’s binding energy, quantitative properties, transformation of crystal structure, and distribution of amorphous/crystalline were all recorded. In particular, the relationship between the physical and chemical properties during the coatingprocess is considered to be the dominant factor controlling the orientation and morphology of that zone (1, T, and 2). TheTiAlSiN coating layer was found to have hardness above 45 GPa and an adhesion above 100 N. In other words, understandingthe evolution and structure of TiAlSin helped us to produce a material with excellent properties that can be used as a hardcoating. Specifically, these properties were induced by a grain refinement of the nano-crystalline structure that correspondsto an increase in the silicon nitride contents.

심인성 어지럼증 환자의 정신과적 증상에 관한 연구

이경규,이지영,김현우,이정엽,백기청,김재일,이근호 大韓神經精神醫學會 1999 신경정신의학 Vol.38 No.5

연구목적 : 어지럼증을 호소하는 환자들 중에 심인성 어지럼증 환자가 상당수 있다는 것은 알려져 있고, 이러한 심인성 어지럼증과 동반되는 정신질환으로는 불안장애, 우울장애, 인격장애 등이 있다. 이에 본 연구에서는 심인성 어지럼증 환자들의 빈도와 정신과적 증상을 알아보고자 하였다. 방 법 : 어지럼증 환자들에게 평형검사, 자세운동측정검사, 자세변화검사, caloric testing을 시행하여 심인성, 말초성 및 중추성의 3군으로 분류한 후 각각 14명, 16명, 32명을 대상으로 하였다. 대상환자들에게 한국판 Beck 우울척도검사(K-BDI), Spielberg의 상태-특성 불안검사(STAI). 간이정신진단검사(SCL-90-R)를 이용하여 정신과적 증상을 측정하여 이들 세 군을 비교분석하였다. 결 과 : 1) 심인성 어지럼증을 가진 환자는 어지럼증을 나타내는 환자 총 62명중에서 14명으로 22.6%를 차지하였다. 2) K-BDI에 따른 세 군간의 비교에서는 세 군간에 유의한 차이를 보이지 않았다. 3) STAI에 따른 세 군간의 비교에서 상태불안(STAI-S) 및 특성불안(STAI-T) 모두에서 세 군간에 유의한 차이를 보이지 않았다. 4) SCL-90-R에 따른 세 군간의 비교에서는 9개의 척도 중에서 공포불안척도에서만 중추성 어지럼증군이 47.56±6.90, 말초성 어지럼증 군이 53.50±13.74, 심인성 어지럼증 군이 58.50±16.05로 심인성 어지럼증 환자군이 중추성 어지럼증 환자군에 비하여 유의하게 높은 것으로 나타났다(p<0.01). 5) 통증 증상에 있어서는 세 군간에 유의한 차이를 보이지 않았고, 위장관 증상과 성기능 장애 증상은 중추성과 말초성 어지럼증 군이 심인성 어지럼증 군에 비하여 유의하게 높은 것으로 나타났다(p<0.01). 결 론 : 상기 결과를 토대로 했을 때 어지럼증 환자들에 대한 정신과적 접근을 위하여 각 군을 나누는 것은 별 의미가 없으며 어지럼증 환자들의 어지럼증 자체에 대한 직접적이고 집중적인 치료가 더욱 필요할 것으로 생각된다. Objectives : This study was aimed to investigate psychiatric symptoms in patients with psychogenic dizziness and compare these findings with those of patients with central and peripheral dizziness. Methods : A total of 62 patients with dizziness was the subject of investigation, and patients were classified into 32 with central type, 16 with peripheral type, and 14 with psychogenic type. Korean standardized Beck Depression Inventory(K-BDI), State and Trait Anxiety Inventory(STAI), and Korean standardized edition of Symptom Checklist 90 Revised(SCL-90-R) were used for the assessment. Statistically, Pearson's chi-square test and one-way ANOVA with Scheffe's test were used with SPSS/PC for windows 6.0. Results : The results were as follows : 1) The proportion of psychogenic dizziness was 22.6% of the total subjects. 2) Total scores of K-BDI were not significantly different among the 3 groups. 3) Total scores of state anxiety and trait anxiety were not significantly different among the 3 groups. 4) In SCL-90-R, psychogenic dizziness group showed significantly higher score of phobic anxiety only(p<0.01) than central dizziness group. And others were not significantly different among the 3 groups. 5) In additional somatic symptoms, pain score was not different among the 3 groups, but gastrointestinal and sexual symptoms scores of central and peripheral dizziness group were significantly higher than those of psychogenic dizziness group(p<0.01). Conclusion : These results suggest that psychiatric symptoms in patients with psychogenic dizziness are not different from those of patients with central or peripheral dizziness. Therefore, the more direct and intensive treatment may be necessary regardless of the type of dizziness.

Adult Patients with Congenital Muscular Torticollis Treated with Bipolar Release : Report of 31 Cases

Lee, Gun Sang,Lee, Myung Ki,Kim, Woo Jae,Kim, Ho Sang,Kim, Jeong Ho,Kim, Yun-Suk The Korean Neurosurgical Society 2017 Journal of Korean neurosurgical society Vol.60 No.1

Objective : We assessed the surgical results of bipolar release in 31 adult patients with uncorrected congenital muscular torticollis (CMT) and more than 12 months of follow-up. Methods : Thirty-one patients underwent a bipolar release of the sternocleidomastoid muscle (SCM) and were retrospectively analyzed. The mean follow-up period was 14.9 months (range, 12-30). The mean age at time of surgery was 30.3 years (range, 20-54). Patients were evaluated with a modified Lee's scoring system, cervicomandibular angle (CMA) measurement, and a global satisfaction rating scale using patient self-reporting. Results : The modified Lee's scoring system indicated excellent results in 4 (12.9%) patients, good in 18 (58.1%), and fair in 9 (29.0%) at the last follow-up after surgery. The improvements in neck movement and head tilt were statistically significant (p<0.05). The preoperative mean CMA was $15.4^{\circ}$ (range, 5.4-29.0), which was reduced to a mean of CMA of $6.3^{\circ}$ (range, 0-25) after surgery (p<0.05). The global satisfaction rating scale was 93.7% (range, 90-100). A transient sensory deficit on the ipsilateral lower ear lobe was noted in three cases. No significant permanent complications occurred. Conclusion : Bipolar release of the SCM is a safe and reliable technique for the treatment of CMT in adults.