Age-Associated Changes in the Vascular Renin-Angiotensin System in Mice

Yoon, Hye Eun,Kim, Eun Nim,Kim, Min Young,Lim, Ji Hee,Jang, In-Ae,Ban, Tae Hyun,Shin, Seok Joon,Park, Cheol Whee,Chang, Yoon Sik,Choi, Bum Soon Hindawi Publishing Corporation 2016 Oxidative medicine and cellular longevity Vol.2016 No.-

<P><I>Background</I>. This study evaluated whether the change in the renin-angiotensin system (RAS) is associated with arterial aging in mice.<I> Methods</I>. Histologic changes and expressions of transforming growth factor-<I>β</I> (TGF-<I>β</I>), collagen IV,<I> fibronectin</I>, angiotensin II (Ang II), angiotensin-converting enzyme (ACE), angiotensin-converting enzyme 2 (ACE2), angiotensin II type 1 receptor (AT1R), angiotensin II type 2 receptor (AT2R), prorenin receptor (PRR), Mas receptor (MasR), endothelial nitric oxide synthase (eNOS), NADPH oxidase 2 and oxidase 4 (Nox2 and Nox4), 8-hydroxy-2′-deoxyguanosine (8-OHdG),<I> 3-nitrotyrosine</I>, and superoxide dismutase 1 and dismutase 2 (SOD1 and SOD2) were measured in the thoracic aortas from 2-month-old, 12-month-old, and 24-month-old C57/BL6 mice.<I> Results</I>. Twenty-four-month-old mice showed significantly increased aortic media thickness and expressions of TGF-<I>β</I>, collagen IV, and fibronectin, compared to 2-month-old and 12-month-old mice. The expressions of PRR, ACE, and Ang II, and AT1R-positive area significantly increased, whereas expressions of ACE2 and MasR and AT2R-positive area decreased with age. The expressions of phosphorylated serine<SUP>1177</SUP>-eNOS, SOD1, and SOD2 decreased, and the 8-OHdG-positive area and the 3-nitrotyrosine-positive area increased with age. The expression of Nox2 significantly increased with age, but that of Nox4 did not change.<I> Conclusions</I>. The enhanced PRR-ACE-Ang II-AT1R axis and reduced ACE2-MasR axis were associated with arterial aging in mice. </P>

Overexpression of tumor necrosis factor receptor-associated protein 1 (TRAP1), leads to mitochondrial aberrations in mouse fibroblast NIH/3T3 cells

( Nim Im Chang ),( Sun Seo Jeong ) 생화학분자생물학회 2014 BMB Reports Vol.47 No.5

Cancer cells undergo uncontrolled proliferation, and aberrantmitochondrial alterations. Tumor necrosis factor receptorassociatedprotein 1 (TRAP1) is a mitochondrial heat shockprotein. TRAP1 mRNA is highly expressed in some cancer celllines and tumor tissues. However, the effects of its overexpressionon mitochondria are unclear. In this study, we assessedmitochondrial changes accompanying TRAP1 overexpression,in a mouse cell line, NIH/3T3. We found that overexpressionof TRAP1 leads to a series of mitochondrial aberrations,including increase in basal ROS levels, and decrease inmitochondrial biogenesis, together with a decrease in peroxisomeproliferator-activated receptor gamma coactivator-1α(PGC-1α) mRNA levels. We also observed increased extracellularsignal-regulated kinase (ERK) phosphorylation, andenhanced proliferation of TRAP1 overexpressing cells. Thisstudy suggests that overexpression of TRAP1 might be a criticallink between mitochondrial disturbances and carcinogenesis.[BMB Reports 2014; 47(5): 280-285]

Characterization of H460R, a Radioresistant Human Lung Cancer Cell Line, and Involvement of Syntrophin Beta 2 (SNTB2) in Radioresistance

Im, Chang-Nim,Kim, Byeong Mo,Moon, Eun-Yi,Hong, Da-Won,Park, Joung Whan,Hong, Sung Hee Korea Genome Organization 2013 Genomics & informatics Vol.11 No.4

A radioresistant cell line was established by fractionated ionizing radiation (IR) and assessed by a clonogenic assay, flow cytometry, and Western blot analysis, as well as zymography and a wound healing assay. Microarray was performed to profile global expression and to search for differentially expressed genes (DEGs) in response to IR. H460R cells demonstrated increased cell scattering and acidic vesicular organelles compared with parental cells. Concomitantly, H460R cells showed characteristics of increased migration and matrix metalloproteinase activity. In addition, H460R cells were resistant to IR, exhibiting reduced expression levels of ionizing responsive proteins (p-p53 and ${\gamma}$-H2AX); apoptosis-related molecules, such as cleaved poly(ADP ribose) polymerase; and endoplasmic reticulum stress-related molecules, such as glucose-regulated protein (GRP78) and C/EBP-homologous protein compared with parental cells, whereas the expression of anti-apoptotic X-linked inhibitor of apoptosis protein was increased. Among DEGs, syntrophin beta 2 (SNTB2) significantly increased in H460R cells in response to IR. Knockdown of SNTB2 by siRNA was more sensitive than the control after IR exposure in H460, H460R, and H1299 cells. Our study suggests that H460R cells have differential properties, including cell morphology, potential for metastasis, and resistance to IR, compared with parental cells. In addition, SNTB2 may play an important role in radioresistance. H460R cells could be helpful in in vitro systems for elucidating the molecular mechanisms of and discovering drugs to overcome radioresistance in lung cancer therapy.

Genome-wide Response of Normal WI-38 Human Fibroblast Cells to 1,763 MHz Radiofrequency Radiation

Im, Chang-Nim,Kim, Eun-Hye,Park, Ae-Kyung,Park, Woong-Yang Korea Genome Organization 2010 Genomics & informatics Vol.8 No.1

Increased exposure of human to RF fields has raised concerns for its potential adverse effects on our health. To address the biological effects of RF radiation, we used genome wide gene expression as the indicator. We exposed normal WI-38 human fibroblast cells to 1763 MHz mobile phone RF radiation at a specific absorption rate (SAR) of 60 W/kg with an operating cooling system for 24 h. There were no alterations in cell numbers or morphology after RF exposure. Through microarray analysis, we identified no differentially expressed genes (DEGs) at the 0.05 significance level after controlling for multiple testing errors with the Benjaminiochberg false discovery rate (BH FDR) method. Meanwhile, 82 genes were differentially expressed between RF-exposed cells and controls when the significance level was set at 0.01 without correction for multiple comparisons. We found that 24 genes (0.08% of the total genes examined) were changed by more than 1.5-fold on RF exposure. However, significant enrichment of any gene set or pathway was not observed from the functional annotation analysis. From these results, we did not find any evidence that non-thermal RF radiation at a 60-W/kg SAR significantly affects cell proliferation or gene expression in WI-38 cells.

Iron chelation study in a normal human hepatocyte cell line suggests that tumor necrosis factor receptor-associated protein 1 (TRAP1) regulates production of reactive oxygen species

Im, Chang-Nim,Lee, Jae-Seon,Zheng, Ying,Seo, Jeong-Sun Wiley Subscription Services, Inc., A Wiley Company 2007 Journal of cellular biochemistry Vol.100 No.2

<P>Iron is an essential component of many proteins, and has crucial roles in the proper functioning of proteins involved in cellular respiration, proliferation, and differentiation. It has been recently reported that the deferoxamine (DFO), an iron chelator, induces mitochondrial dysfunction, characterized by an attenuation of oxidative phosphorylation, as well as senescence-like cellular morphology. However, the effects of DFO on mitochondrial heat shock proteins (HSPs) remain poorly understood. In this study, we examined the effect of DFO on tumor necrosis factor receptor-associated protein 1 (TRAP1), a representative mitochondrial HSP, in a normal human hepatocyte cell line, Chang cells. DFO specifically decreased TRAP1 levels, increasing reactive oxygen species (ROS) and caveolin-1 (Cav-1), a marker protein of senescence. To examine whether these effects of DFO are reversed, we established TRAP1-overexpressing Chang cells. DFO treatment to TRAP1-overexpressing cells resulted in decreases in levels of ROS, Cav-1, glutathione peroxidase (GPX), and manganese superoxide dismutase (MnSOD) levels as well as senescence-associated β-galactosidase (SA β-gal) activity. These results suggest that TRAP1 might play a role in protecting mitochondria against damaging stimuli via decrease of ROS generation. J. Cell. Biochem. 100: 474–486, 2007. © 2006 Wiley-Liss, Inc.</P>

Application of Chlorophyll Fluorescence Imaging Analysis for the Selection of Rapidly Superior Germplasms of Peach(Prunus persica)

Haet-Nim Jeong,Je-Chang Lee,Ju-Hyeon Kim,Ki-Ok Lee,Eun Ha Chang,Jae Hee Won,Kyeong-Ho Kim,Ki-Young Choi 한국육종학회 2023 한국육종학회 공동학술발표집 Vol.2023 No.-

The Establishment of Tumor Necrosis Factor Receptor-associated Protein1 (TRAP1) Transgenic Mice and Severe Fat Accumulation in the Liver of TRAP1 Mice during Liver Regeneration

Im, Chang-Nim,Zheng, Ying,Kim, Sun Hye,Huang, Tai-Qin,Cho, Du-Hyong,Seo, Jeong-Sun Korean Society for Bioinformatics 2013 Interdisciplinary Bio Central (IBC) Vol.5 No.4

Introduction: Tumor necrosis factor receptor-associated protein 1 (TRAP1) is a mitochondrial heat shock protein (HSP), which belongs to HSP90 family. It plays important roles in regulating mitochondrial integrity, protecting against oxidative stress, and inhibiting cell death. Recent studies suggest that TRAP1 is linked to mitochondria and its metabolism. In this study, we established TRAP1 transgenic mice and performed partial hepatectomy (PH) on wild-type (WT) and TRAP1 transgenic mice to investigate the function of TRAP1 during liver regeneration. Results and Discussion: We found that TRAP1 was highly expressed in liver as well as kidney. In addition, liver regeneration slightly decreased together with increased fatty liver and inflammation at 72 hr after PH in TRAP1 transgenic mice compared with WT control group mice. Concomitantly, we observed decreased levels of p38 protein in TRAP1 transgenic mice compared with WT control group mice. These results suggest that TRAP1 plays a critical role in liver energy balance by regulating lipid accumulation during liver regeneration. Conclusions and Prospects: To our knowledge, we reported, for the first time, that liver regeneration slightly reduced together with increased fat accumulations after PH in TRAP1 transgenic mice compared with WT control group mice. Concomitantly, we observed decreased levels of p38 protein in TRAP1 transgenic mice compared with WT control group mice. Overexpression of TRAP1 might affect liver regeneration via disturbing mitochondrial function leading to fatty liver in vivo.

Heat Shock Factor 1 Depletion Sensitizes A172 Glioblastoma Cells to Temozolomide via Suppression of Cancer Stem Cell-Like Properties

Im, Chang-Nim,Yun, Hye Hyeon,Lee, Jeong-Hwa MDPI 2017 INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES Vol.18 No.2

<P>Heat shock factor 1 (HSF1), a transcription factor activated by various stressors, regulates proliferation and apoptosis by inducing expression of target genes, such as heat shock proteins and Bcl-2 (B-cell lymphoma 2) interacting cell death suppressor (BIS). HSF1 also directly interacts with BIS, although it is still unclear whether this interaction is critical in the regulation of glioblastoma stem cells (GSCs). In this study, we examined whether small interfering RNA-mediated BIS knockdown decreased protein levels of HSF1 and subsequent nuclear localization under GSC-like sphere (SP)-forming conditions. Consistent with BIS depletion, HSF1 knockdown also reduced sex determining region Y (SRY)-box 2 (SOX2) expression, a marker of stemness, accompanying the decrease in SP-forming ability and matrix metalloprotease 2 (MMP2) activity. When HSF1 or BIS knockdown was combined with temozolomide (TMZ) treatment, a standard drug used in glioblastoma therapy, apoptosis increased, as measured by an increase in poly (ADP-ribose) polymerase (PARP) cleavage, whereas cancer stem-like properties, such as colony-forming activity and SOX2 protein expression, decreased. Taken together, our findings suggest that targeting BIS or HSF1 could be a viable therapeutic strategy for GSCs resistant to conventional TMZ treatment.</P>

Enhancement of SOX-2 expression and ROS accumulation by culture of A172 glioblastoma cells under non-adherent culture conditions.

Im, Chang-Nim,Yun, Hye Hyeon,Yoo, Hyung Jae,Park, Myung-Jin,Lee, Jeong-Hwa National Hellenic Research Foundation 2015 ONCOLOGY REPORTS Vol.34 No.2

<P>More efficient isolation and identification of cancer stem cells (CSCs) would help in determining their fundamental roles in tumor biology. The classical tool for this purpose is anchorage-independent tumorsphere culture. We compared the effects of differently textured culture plates and serum deprivation on the acquisition of CSC properties of A172 glioblastoma cells. Cells were cultured on standard polystyrene-treated plates, ultra-low attachment, poly (2-hydroxyethyl methacrylate)-coated plates, and 1% agar-coated plates with 10% serum or in serum-free glioblastoma sphere medium (GBM). Based on mitochondrial reductase activity and subG1 proportions, non-adherent conditions had a greater impact on A172 cell viability than serum deprivation. Among the stemness-related genes, SOX-2 expression was significantly upregulated by serum deprivation under non-adherent conditions, while several epithelial-to-mesenchymal transition (EMT)-related genes were less dependent on serum. In addition, reactive oxygen species (ROS) accumulation in A172 cells was significantly increased in GBM under non-adherent conditions. Despite the correlation between SOX-2 induction and ROS accumulation, treatment with the ROS scavenger N-acetyl-l-cysteine did not prevent SOX-2 expression, suggesting that ROS accumulation is not an essential requirement for induction of SOX-2. Our results suggested that cultivation of cancer cells under conditions of serum deprivation in an anchorage-independent manner may enrich SOX-2-expressing CSC-like cells in vitro.</P>

Classification of Biological Effect of 1,763 MHz Radiofrequency Radiation Based on Gene Expression Profiles

Im, Chang-Nim,Kim, Eun-Hye,Park, Ae-Kyung,Park, Woong-Yang Korea Genome Organization 2010 Genomics & informatics Vol.8 No.1

Radiofrequency (RF) radiation might induce the transcription of a certain set of genes as other physical stresses like ionizing radiation and UV. To observe transcriptional changes upon RF radiation, we exposed WI-38, human lung fibroblast cell to 1763 MHz of mobile phone RF radiation at 60 W/kg of specific absorption rate (SAR) for 24h with or without heat control. There were no significant changes in cell numbers and morphology after exposure to RF radiation. Using quantitative RT-PCR, we checked the expression of three heat shock protein (HSP) (HSPA1A, HSPA6 and HSP105) and seven stress-related genes (TNFRSF11B, FGF2, TGFB2, ITGA2, BRIP1, EXO1, and MCM10) in RF only and RF/HS groups of RF-exposed cells. The expressions of three heat shock proteins and seven stress-related genes were selectively changed only in RF/HS groups. Based on the expression of ten genes, we could classify thermal and non-thermal effect of RF-exposure, which genes can be used as biomarkers for RF radiation exposure.