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.

Heme oxygenase-1 induced by desoxo-narchinol-A attenuated the severity of acute pancreatitis via blockade of neutrophil infiltration

Bae, Gi-Sang,Kim, Dong-Goo,Jo, Il-Joo,Choi, Sun-Bok,Kim, Myoung-Jin,Shin, Joon Yeon,Kim, Dong-Uk,Song, Ho-Joon,Joo, Myungsoo,Park, Sung-Joo ELSEVIER 2019 INTERNATIONAL IMMUNOPHARMACOLOGY Vol.69 No.-

<P><B>Abstract</B></P> <P>Heme oxygenase-1 (HO-1) has an anti-inflammatory action in acute pancreatitis (AP). However, its mechanism of action and natural compounds/drugs to induce HO-1 in pancreas are not well understood. In this study, we investigated the regulatory mechanisms of HO-1 during AP using desoxo-narchinol-A (DN), the natural compound inducing HO-1 in the pancreas. Female C57/BL6 Mice were intraperitoneally injected with supramaximal concentrations of cerulein (50 μg/kg) hourly for 6 h to induce AP. DMSO or DN was administered intraperitoneally, then mice were sacrificed 6 h after the final cerulein injection. Administration of DN increased pancreatic HO-1 expression through activation of activating protein-1, mediated by mitogen-activated protein kinases. Furthermore, DN treatment reduced the pancreatic weight-to-body weight ratio as well as production of digestive enzymes and pro-inflammatory cytokines. Inhibition of HO-1 by tin protoporphyrin IX abolished the protective effects of DN on pancreatic damage. Additionally, DN treatment inhibited neutrophil infiltration into the pancreas via regulation of chemokine (C-X-C motif) ligand 2 (CXCL2) by HO-1. Our results suggest that DN is an effective inducer of HO-1 in the pancreas, and that HO-1 regulates neutrophil infiltration in AP via CXCL2 inhibition.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Desoxo-narchinol-A (DN) is a natural compound of HO-1 inducer in pancreas. </LI> <LI> Mechanism of DN-induced HO-1 is mediated by MAPK/Activator Protein-1/HO-1 signaling. </LI> <LI> DN-induced HO-1 blocks neutrophil infiltration into pancreas via inhibition of CXCL2. </LI> <LI> DN inhibits cerulein-induced acute pancreatitis (AP) and AP-associated lung injury. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

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.

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.

Characterization and multicolor upconversion emission properties of BaMoO₄: Yb³⁺, Ln³⁺ (Ln = Tm, Ho, Tm/Ho) microcrystals

Ray, Schindra Kumar,Kshetri, Yuwaraj K.,Yamaguchi, Tokutaro,Kim, Tae-Ho,Lee, Soo Wohn Elsevier 2019 Journal of solid state chemistry Vol.272 No.-

<P><B>Abstract</B></P> <P>Hydrothermal process was employed to synthesize the Yb<SUP>3+</SUP>/Tm<SUP>3+</SUP>, Yb<SUP>3+</SUP>/Ho<SUP>3+</SUP> and Yb<SUP>3+</SUP>/Tm<SUP>3+</SUP>/Ho<SUP>3+</SUP> doped BaMoO<SUB>4</SUB> octahedron microcrystals (0.50–5.0 µm). The synthesized phosphors have scheelite tetragonal structure. The elemental mapping suggests the uniform distribution of elements in the samples. The oxidation state of samples were investigated by X-ray photoelectron spectroscopy (XPS) which indicates the existence of Ba<SUP>2+</SUP>, Mo<SUP>6+</SUP>, O, Yb<SUP>3+</SUP>, Tm<SUP>3+</SUP> and Ho<SUP>3+</SUP> in samples. The presence of rare earth ions was also verified by observation of specific absorption peaks in diffuse reflectance spectra (DRS). The tunable multicolor upconversion (UC) emissions were successfully obtained under 980 nm NIR excitation by precisely adjusting the concentration of rare earth ions. The as prepared sample exhibits blue, green and red emission as a result of energy transfer from the Yb<SUP>3+</SUP> to Tm<SUP>3+</SUP> and Ho<SUP>3+</SUP> ions. The power dependent UC emission spectra show the two photonic processes. The energy transfer mechanism from Yb<SUP>3+</SUP> to Tm<SUP>3+</SUP> and Ho<SUP>3+</SUP> was explained <I>via</I> an energy level analysis.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Synthesis of BaMoO<SUB>4</SUB>: Yb<SUP>3+</SUP>, Ln<SUP>3+</SUP> (Ln = Tm, Ho, Tm/Ho) by hydrothermal process. </LI> <LI> Investigation of upconversion luminescence of phosphors under 980 nm excitation. </LI> <LI> Obtaining the multicolor emission by adjusting doped rare-earth ions concentration. </LI> <LI> Explanation of photonic process and energy transfer mechanism. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Multicolor upconversion emission properties of BaMoO<SUB>4</SUB>: Yb<SUP>3+</SUP>, Ln<SUP>3+</SUP> (Ln = Tm, Ho, Tm/Ho) octahedrons</P> <P>[DISPLAY OMISSION]</P>

FK506이 T 림프구 사멸에서 활성산소 생성에 미치는 영향

이호균(Ho Kyun Lee),정상영(Sang Young Chung),최수진나(Soo Jin Na Choi) 대한외과학회 2009 Annals of Surgical Treatment and Research(ASRT) Vol.77 No.5

Purpose: Tacrolimus (FK506) has been widely used as an immunosuppressant in organ transplanted recipients to suppress organ rejection phenomenon. We investigated the role of oxidative stress and heme oxygense-1 by FK506 on human Jurkat T cells. Methods: The cells viability was examined by DAPI stain, enzyme activity of caspase family proteins, and western blotting for Baks, PUMA, iNOS, HO-1. Cells were cultured in the absence or presence of CoPPIX or ZnPPIX and the fluorescence intensity was analyzed using a flow cytometry. Results: Treatment with FK506 increased the generation of reactive oxygen species (ROS), including hydrogen peroxide and superoxide anion, and NO in Jurkat cells in a dose-dependent manner. Immunohistochemistry and Western blot analysis data revealed the hemoxygenase-1 (HO-1) was induced by the addition of FK506 in Jurkat cells. Induction of CoPP, HO-1 inducer, resulted in decreased intracellular H₂O₂ and NO concentrations. Instead ZnPP, an HO-1 competitive inhibitor did it reversely. In addition, ZnPP regulates iNOS protein synthesis by inhibition of HO-1. Conclusion: Increase of HO-1 expression would induce to decrease the intracellular H₂O₂ and NO concentrations. Also, HO-1 would regulate iNOS protein synthesis. Consequently, we can expect the regulation of HO-1 expression with concomitants use of FK506 to suppress organ rejection phenomenon by enhancing apoptosis.

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>

Mg₂SiO₄ : La, Ho 열형광선량계에서 활성제 농도가 글로우 커브에 미치는 영향 La, Ho TLD on Activation Concentration

김영국,손인호,채건식,노경석,오재근,이은숙 경남대학교 신소재연구소 1996 論文集 Vol.6 No.-

본 연구에서는 Mg₂SiO₄에 활성화 물질로 La, Ho를 첨가하여 열형광체를 제작하였고 불순물의 농도를 1wt.% ∼5 wt.%까지 변화시키면서 열평광강도의 glow curve를 측정하였다. 도한 열형광체의 glow curve를 peak shape법으로 분석해서 TL특성에 대한 포획 매개변수와 활성화 에너지, 발광차수, 선량의존성등을 조사하였으며, 그 물리적 특성을 조사하고 선량계로서 타당성과 실용성을 확인하였다. The Mg₂SiO₄: La, Ho thermoluminescent phospher has been prepared by sintring Mg₂SiO₄after doping the transition elements La and Ho. The heating rate is 10℃/sec at this thermoluminescent phospher are heated. The maximum peaks are found in the measured Mg₂SiO₄: La and Ho. TL glow curve at 229℃ and 345 C when the 1 wt.%-5 wt.%. The glow curve of TLD increased TL intensity and temperature of peak appears to the high temperature when the heating rate is l0℃/sec-25℃/sec. The activation energy of the main peak has been estimated by the peak shape method. The estimated activation energies are 1.77 eV. 1.52 eV respectively. The thermoluminescence process in Mg₂SiO₄: La and Ho are found to the 2nd order when the main peak of the glow curve is analyzed by peak shape method. The dose responses of Mg₂SiO₄: La and Ho TLD are linear up to intensity of X-ray.

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.