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.

Induction of heme oxygenase-1 protects against podocyte apoptosis under diabetic conditions

Lee, Sang Choel,Han, Seung Hyeok,Li, Jin Ji,Lee, Sun Ha,Jung, Dong-Sub,Kwak, Seung-Jae,Kim, Seung Hye,Kim, Dong Ki,Yoo, Tae-Hyun,Kim, Jin Hyun,Chang, Se-Ho,Han, Dae Suk,Kang, Shin-Wook International Society of Nephrology 2009 Kidney international Vol.76 No.8

Heme oxygenase-1 (HO-1) is an anti-oxidant enzyme normally upregulated in response to oxidant injury. Here we determined the role of HO-1 in podocyte apoptosis in glomeruli of streptozotocin-treated rats and in immortalized mouse podocytes cultured in media containing normal or high glucose. HO-1 expression, its activity, the ratio of Bax/Bcl-2 protein, and active caspase-3 fragments were all significantly higher in isolated glomeruli of diabetic rats and in high glucose–treated podocytes. These increases were inhibited by zinc protoporphyrin treatment of the rats or by HO-1 siRNA treatment of the podocytes in culture. The number of apoptotic cells was also significantly increased in the glomeruli of diabetic rats and in high glucose–treated podocytes. Inhibition of HO-1 accentuated the increase in apoptotic cells both in vivo and in vitro. Our findings suggest that HO-1 expression protects against podocyte apoptosis under diabetic conditions.

Ethanol Extract of Ganoderma lucidum Augments Cellular Anti-oxidant Defense through Activation of Nrf2/HO-1

Lee, Yoo-hwan,Kim, Jung-hee,Song, Choon-ho,Jang, Kyung-jeon,kim, Cheol-hong,Kang, Ji-Sook,Choi, Yung-hyun,Yoon, Hyun-Min KOREAN PHARMACOPUNCTURE INSTITUTE 2016 Journal of pharmacopuncture Vol.19 No.1

Objectives: The mushroom Ganoderma lucidum has been widely used as a traditional herbal medicine for many years. Although several studies have focused on the anti-oxidative activity of this mushroom, the molecular mechanisms underlying its activity have not yet been clearly established. The present study investigated the cytoprotective effect of ethanol extract of Ganoderma lucidum (EGL) against oxidative stress (hydrogen peroxide, $H_2O_2$) and elucidated the underlying mechanisms in a C2C12 myoblast cell line. Methods: Oxidative stress markers were determined by using the comet assay to measure reactive oxygen species (ROS) generation and deoxyribonucleic acid (DNA) damage. Cell viability and Western blotting analyses were employed to evaluate the cellular response to EGL and $H_2O_2$ in C2C12 cells. Transfection with nuclear factor erythroid 2-related factor 2 (Nrf2)-specific small interfering ribonucleic acid (siRNA) was conducted to understand the relationship between Nrf2 expression and $H_2O_2$-induced growth inhibition. Results: The results showed that EGL effectively inhibited $H_2O_2$-induced growth and the generation of ROS. EGL markedly suppressed $H_2O_2$-induced comet-like DNA formation and phosphorylation of histone H2AX at serine 139 ($p-{\gamma}H2AX$), a widely used marker of DNA damage, suggesting that EGL prevented $H_2O_2$-induced DNA damage. Furthermore, the EGL treatment effectively induced the expression of Nrf2, as well as heme oxygenase-1 (HO-1), with parallel phosphorylation and nuclear translocation of Nrf2 in the C2C12 myoblasts. However, zinc protoporphyrin IX, a HO-1 inhibitor, significantly abolished the protective effects of EGL against $H_2O_2$-induced accumulation of ROS and reduced cell growth. Notably, transient transfection with Nrf2-specific siRNA attenuated the cytoprotective effects and HO-1 induction by EGL, indicating that EGL induced the expression of HO-1 in an Nrf2-dependent manner. Conclusion: Collectively, these results demonstrate that EGL augments the cellular anti-oxidant defense capacity through activation of Nrf2/HO-1, thereby protecting C2C12 myoblasts from $H_2O_2$-induced oxidative cytotoxicity.

Protective Effect of Heme Oxygenase-1 on High Glucose-Induced Pancreatic β-Cell Injury

Lee, Eun-Mi,Lee, Young-Eun,Lee, Esder,Ryu, Gyeong Ryul,Ko, Seung-Hyun,Moon, Sung-Dae,Song, Ki-Ho,Ahn, Yu-Bae Korean Diabetes Association 2011 Diabetes and Metabolism Journal Vol.35 No.5

<P><B>Background</B></P><P>Glucose toxicity that is caused by chronic exposure to a high glucose concentration leads to islet dysfunction and induces apoptosis in pancreatic β-cells. Heme oxygenase-1 (HO-1) has been identified as an anti-apoptotic and cytoprotective gene. The purpose of this study is to investigate whether HO-1 up-regulation when using metalloprotophyrin (cobalt protoporphyrin, CoPP) could protect pancreatic β-cells from high glucose-induced apoptosis.</P><P><B>Methods</B></P><P>Reverse transcription-polymerase chain reaction was performed to analyze the CoPP-induced mRNA expression of HO-1. Cell viability of INS-1 cells cultured in the presence of CoPP was examined by acridine orange/propidium iodide staining. The generation of intracellular reactive oxygen species (ROS) was measured using flow cytometry. Glucose stimulated insulin secretion (GSIS) was determined following incubation with CoPP in different glucose concentrations.</P><P><B>Results</B></P><P>CoPP increased HO-1 mRNA expression in both a dose- and time-dependent manner. Overexpression of HO-1 inhibited caspase-3, and the number of dead cells in the presence of CoPP was significantly decreased when exposed to high glucose conditions (HG). CoPP also decreased the generation of intracellular ROS by 50% during 72 hours of culture with HG. However, decreased GSIS was not recovered even in the presence of CoPP.</P><P><B>Conclusion</B></P><P>Our data suggest that CoPP-induced HO-1 up-regulation results in protection from high glucose-induced apoptosis in INS-1 cells; however, glucose stimulated insulin secretion is not restored.</P>

峿堂 李象秀의 『史記』 評述에 대하여

이현호(Lee Hyun-Ho) 동양한문학회(구 부산한문학회) 2010 동양한문학연구 Vol.31 No.-

본고는 峿堂李象秀(1820-1882)가 『사기』에 대해서 남긴 비평적 저술을 살핀 논문이다. 이상수는 텍스트의 선택이나텍스트의 선본에 관심을 갖지않고 독서하는 방법에 주목하였다. 그리하여 대부분의 사람들의 독서법이 잘못되었기에 글을 잘 짓는 자가 드물다 하면서, 맹목적 독서가 아닌 能思의 독서를 해야함을 강조하였다. 이러한 이상수의 독서론은 ‘虛讀’이 아닌 ‘實讀’이라 명명할 수 있는데, 독서에 潛心해야 志向이 정해지고 見識이 분명해져 결국에는 작자의 本心을 파악하며 글 전체의 大義를 구명할 수 있게 된다 하였다. 또한 이상수는 독서를 작문의 기초단계로 파악하지 않고, 오히려 작문 이후에 더 독서를 잘 할 수 있다는 의견을 피력한다. 곧 작문법을 독서론에 적용하여 체계적이고도 분석적으로 글을 읽어야 글에 나타난 작자의 묘처를 알 수 있게 된다고 하였다. 이러한 독서작문론을 『사기』에 적용하여 비평적 언술을 남기게 된다. 혹리열전 에서는 저작의도를 후세의 경계가 아닌 한무제의 어리석고 현명하지 못함을 기롱하고 풍자하는 것이라 하였고, ‘脈理’에 입각하여 입전 순서가 단절되지 않고 연속되어 있음을 논증하고 있다. 화식열전 에서는 작자의 本心과 宗旨를 글의 표면에서 찾지 않고 글에 드러나 있지 않은 곳에서 찾고 있으며, 사람들이 재화의 증식만 추구하여 올바른 가치를 망각하는 모습을 안타까워한 것이 이 傳을 創立한 사마천의 본심이라 하였다. 또한 문장의 ‘摺’과 ‘承’이라는 段落구성에서 접속 기법의 차원으로 화식전 에대하여 수사학적 분석을 하고 있다. 이러한 것들에서 이상수의 독서작문론의 의의와 『사기』에 대한 평술의 실상을 확인할 수 있다. The present study analyzes a critical review by Lee Sang-Soo (pseudonym: eh-dang, 1820-1882) on the Records of the Great Historian (Shiji or 史記, Sima Qian;109 BC - 91 BC). Lee focused on the mode of reading, rather than on the choice and content of text. He pointed that most people employ an improper mode of reading and hence good writers are rare, thereby he urged to exercise truthful and proper reading instead of pointless reading. Such a theory of reading by Lee can be defined as true reading (實讀), as opposed to a vain reading (實讀), where he asserted that being engrossed in reading is what offers the inclination of messages and firmly sets the insight of reader; only then, one can eventually recite the true intention of the writer and be able to define the ultimate message of the whole text. Further, Lee did not identify reading as a prerequisite step for writing but instead expressed that reading can be improved with writing exercise. In other words, applying writing skills to the reading theory that one should read text in an orderly and analytic manner in order to appreciate the writer's merit from the text. He applied this theory of reading-by-writing in his critical review on the Records of the Great Historian. He stated that the Biographies of Cruel Officials (Kuli liezhuan, 酷吏列傳) of the Records is not intended as a discipline for succeeding generations but to deride and satire the Emperor Wu of Han for his folly and poor wisdom, arguing that the contents are connected by the thread of logic in consecutive manner, without disruption. While discussing on the Biographies of Usurers (Huozhi liezhuan, 貨殖列傳), he finds the writer's true intention and ultimate message from the unmentioned context instead of the textual contents, that frustration was the real intention behind Sima Qian's establishment of the Records, for people becoming obsessed with material wealth and in turn oblivious to the value of morals. He also conducted rhetoric analysis on the Biographies of Usurers in terms of conjunctive method on the paragraph composition characterized by remit and receiving. Such are the particulars that present the significance of Lee's reading-bywriting theory, as well as the insight to his critical assessment on the Records of the Great Historian.

Combined Gene Therapy with Hypoxia-Inducible Factor-1α and Heme Oxygenase-1 for Therapeutic Angiogenesis

Bhang, Suk Ho,Kim, Ju Hee,Yang, Hee Seok,La, Wan-Geun,Lee, Tae-Jin,Kim, Ga Hee,Kim, Hyun Ah,Lee, Minhyung,Kim, Byung-Soo Mary Ann Liebert 2011 Tissue engineering. Part A Vol.17 No.7

<P>Transfection with either hypoxia-inducible factor-1α (HIF-1α) or heme oxygenase-1 (HO-1) gene can induce neovascularization in ischemic tissues. Although expression of transfected HIF-1α gene occurs rapidly, the expressed HIF-1α protein degrades quickly, limiting its therapeutic efficacy. Meanwhile, expressed HO-1 protein does not rapidly undergo degradation, but gene expression occurs a couple of days after transfection, resulting in apoptosis and a delay in angiogenesis in ischemic tissues at the incipient period of HO-1 gene transfection. We hypothesize that combined delivery of HIF-1α and HO-1 gene will enhance antiapoptosis and neovascularization in ischemic tissue compared with HIF-1α or HO-1 single-gene therapy. To test this hypothesis, ischemic mouse hindlimbs were treated with HIF-1α and/or HO-1 gene therapy. The combined gene therapy proved superior to both single-gene therapies, resulting in rapid expression of HIF-1α gene and long-term maintenance of expressed HO-1 protein. The apoptosis in the ischemic region was significantly less, and angiogenic growth factor secretion and angiogenesis were greater in the combined gene therapy than in either of the single-gene therapies. Our results suggest that a combined gene therapy of HIF-1α and HO-1 enhances the transfection of both genes and improves angiogenesis compared with either single-gene therapy.</P>

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>

White luminescence of Ho3+/Tm3+/Yb3+-codoped CaWO4 synthesized via citrate complex route assisted by microwave irradiation

CHO, Hyun,HWANG, Seok Min,LEE, Jae Bin,KA, Dong Hyun,KIM, Tae Wan,LEE, Bo Seul,LEE, Ji Young,LEE, Jung-Il,RYU, Jeong Ho Elsevier 2014 Transactions of Nonferrous Metals Society of China Vol.24 No.suppl1

제주도 지하수 질산염 농도의 시·공간적 변화 특성: 장기(1993-2015) 모니터링 자료의 평가

김호림(Ho-Rim Kim),오준섭(Junseop Oh),도현권(Hyun-Kwon Do),이경진(Kyung-Jin Lee),현익현(Ik-Hyun Hyun),오상실(Sang-Sil Oh),감상규(Sang-Kyu Kam),윤성택(Seong-Taek Yun) 대한자원환경지질학회 2018 자원환경지질 Vol.51 No.1

1993년부터 2015년까지 관측된 제주도 지하수 장기모니터링 관측정(N = 4,835)에서 수집된 지하수 수질자료(N = 21,568)를 기반으로 질산성질소의 시공간적 변동 특성을 평가하였다. 제주도 지하수의 질산성질소 농도의 중앙값은 2.5 mg/L로서 다른 국가나 대륙의 조사 결과에 비해 다소 높거나 유사한 것으로 나타났다. 또한 지하수 용도, 행정구역 및 고도 별로 유의한 차이를 보였다. 특히, 산간 지역에 비해 저지대 해안가에 위치한 농업 및 주거지역에서 농도가 높음을 확인하였다. Mann-Kendall 및 Sen’s slope 분석을 활용한 질산성질소 농도의 추세 분석 결과, 하류 저지 대에 비해 중산간지역에서의 질산성질소 농도 증가 경향이 뚜렷하였다. 제주도 내 토지 피복의 시계열 변화 특성과 결부 지어 보면, 중산간지역의 오염 증가 추세는 농업지역의 확장 등 인위적 활동 증가에 기인한 결과로 판단된다. 반면,기지정된 지하수자원특별관리구역에서는 전반적으로 질산성질소 농도의 감소 경향이 나타났는데, 이는 지하수 관리 측면에서 수질관리를 위한 적극적인 정책이 유효함을 시사한다. 본 연구에서는 제주도 지하수의 질산성질소 오염관리를 위한 적정 방안을 제안한다. The spatio-temporal variations of nitrate concentrations in groundwater of Jeju Island were evaluated by an analysis of time series groundwater quality data (N = 21,568) that were collected from regional groundwater monitoring (number of wells = 4,835) for up to 20 years between 1993 and 2015. The median concentration of NO 3 -N is 2.5 mg/L, which is slightly higher than those reported from regional surveys in other countries. Nitrate concentrations of groundwater in wells tend to significantly vary according to different water usage (of the well), administrative districts, and topographic elevations: nitrate level is higher in low-lying agricultural and residential areas than those in high mountainous areas. The Mann-Kendall trend test and Sen’s slope analysis show that nitrate concentration in mid-mountainous areas tends to increase, possibly due to the expansion of agricultural areas toward highland. On the other hand, nitrate concentrations in the Specially Designated Groundwater Quality Protection Zones show the temporally decreasing trend, which implies the efficiency of groundwater management actions in Jeju. Proper measures for sustainable groundwater quality management are suggested in this study.

Sauchinone Suppresses Pro-inflammatory Mediators by Inducing Heme Oxygenase-1 in RAW264.7 Macrophages

Li, Bin,Lee, Dong-Sung,Choi, Hyun-Gyu,Kim, Kyoung-Su,Kang, Dae-Gil,Lee, Ho-Sub,Jeong, Gil-Saeng,Kim, Youn-Chul Pharmaceutical Society of Japan 2011 BIOLOGICAL & PHARMACEUTICAL BULLETIN Vol.34 No.10

<P>Sauchinone, a biologically active lignan isolated from the roots of <I>Saururus chinensis</I> (L<SMALL>OUR</SMALL>.) B<SMALL>AILL</SMALL>. (Saururaceae), is reported to exert a variety of biological activities, such as hepatoprotective, anti-inflammatory actions and inhibitory effects on bone resorption. In this study, we investigated the effect of sauchinone in suppressing cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expression, leading to a reduction in COX-2-derived prostaglandin E<SUB>2</SUB> (PGE<SUB>2</SUB>) and iNOS-derived nitric oxide (NO) production in lipopolysaccharide (LPS) stimulated RAW264.7 macrophages. Present study also demonstrates the effects of sauchinone in inducing heme oxygenase-1 (HO-1) expression and an increase in heme oxygenase (HO) activity in RAW264.7 macrophages. The effects of sauchinone on LPS-induced PGE<SUB>2</SUB>, NO, tumor necrosis factor-α (TNF-α) and interlukine-1β (IL-1β) production were partially reversed by the HO-1 inhibitor Tin protoporphyrin was also seen in this study. In addition, we found that treatment with extracellular signal-regulated kinase (ERK) inhibitor (PD98059) reduced sauchinone-induced HO-1 expression. Sauchinone also increased ERK phosphorylation. These results suggest that sauchinone inhibits pro-inflammatory mediators through expression of anti-inflammatory HO-1 <I>via</I> ERK pathway.</P>