58 results on '"Yeo IJ"'
Search Results
2. Corrigendum to "Deletion of Chitinase-3-like 1 accelerates stroke development through enhancement of Neuroinflammation by STAT6-dependent M2 microglial inactivation in Chitinase-3-like 1 knockout mice" [Exp Neurol. 2020 Jan:323:113082].
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Im JH, Yeo IJ, Park PH, Choi DY, Han SB, Yun J, and Hong JT
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- 2024
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3. Anti-chitinase-3-like 1 antibody attenuated atopic dermatitis-like skin inflammation through inhibition of STAT3-dependent CXCL8 expression.
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Yu JE, Jeon SH, Kim MJ, Kim DH, Koo JK, Kim TH, Kim B, Yoon JY, Lim YS, Park SR, Yeo IJ, Yun J, Son DJ, Han SB, Lee YS, and Hong JT
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- Humans, Animals, Skin drug effects, Skin pathology, Skin metabolism, Male, Mice, Inbred BALB C, Phthalic Anhydrides pharmacology, Antibodies pharmacology, Mice, Female, Inflammation drug therapy, Inflammation metabolism, Dermatitis, Atopic drug therapy, Dermatitis, Atopic immunology, Dermatitis, Atopic metabolism, Dermatitis, Atopic pathology, STAT3 Transcription Factor metabolism, STAT3 Transcription Factor antagonists & inhibitors, Interleukin-8 metabolism, Chitinase-3-Like Protein 1 antagonists & inhibitors, Chitinase-3-Like Protein 1 metabolism
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Background and Purpose: Chitinase-3-like 1 (CHI3L1) causes skin inflammation in the progression of atopic dermatitis. We investigated if anti-CHI3L1 antibody could prevent the development of atopic dermatitis and its mechanisms of action., Experimental Approach: The effect of CHI3L1 antibody on phthalic anhydride-induced atopic dermatitis animal model and in vitro reconstructed human skin (RHS) model were investigated. Expression and release of atopic dermatitis-related cytokines were determined using an enzyme-linked immunosorbent assay, and RT-qPCR, STAT3 and CXCL8 signalling were measured by western blotting., Key Results: Anti-CHI3L1 antibody suppressed phthalic anhydride-induced epidermal thickening, clinical score, IgE level and infiltration of inflammatory cells, and reduced phthalic anhydride-induced inflammatory cytokines concentration. In addition, CHI3L1 antibody treatment inhibited the expression of STAT3 activity in phthalic anhydride-treated skin. It was also confirmed that CHI3L1 antibody treatment alleviated atopic dermatitis-related inflammation in the RHS model. The inhibitory effects of CHI3L1 antibody was similar or more effective compared with that of the IL-4 antibody. We further found that CHI3L1 is associated with CXCL8 by protein-association network analysis. siRNA of CHI3L1 blocked the mRNA levels of CHI3L1, IL-1β, IL-4, CXCL8, TSLP, and the expression of CHI3L1 and p-STAT, and the level of CXCL8, whereas recombinant level of CXCL8 was elevated. Moreover, siRNA of STAT3 reduced the mRNA level of these cytokines. CHI3L1 and p-STAT3 expression correlated with the reduced CXCL8 level in the RHS in vitro model., Conclusion and Implications: Our data demonstrated that CHI3L1 antibody could be a promising effective therapeutic drug for atopic dermatitis., (© 2024 The Author(s). British Journal of Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.)
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- 2024
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4. Corrigendum to "(E)-2-methoxy-4-(3-(4-methoxyphenyl)prop-1-en-1-yl)phenol alleviates inflammatory responses in LPS-induced mice liver sepsis through inhibition of STAT3 phosphorylation" [Int. Immunopharmacol. 125(Part B) (2023) 111124].
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Kim B, Yu JE, Yeo IJ, Son DJ, Lee HP, Roh YS, Lim KH, Yun J, Park H, Han SB, and Hong JT
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- 2024
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5. Correction to: PRDX6 Inhibits Neurogenesis through Downregulation of WDFY1-Mediated TLR4 Signal.
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Yeo IJ, Park MH, Son DJ, Kim JY, Nam KT, Hyun BK, Kim SY, Jung MH, Song MJ, Chun HO, Lee TH, Han SB, and Hong JT
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- 2024
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6. Erratum: Inhibition of Chitinase-3-like-1 by K284-6111 Reduces Atopic Skin Inflammation via Repressing Lactoferrin.
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Jeon SH, Lee YS, Yeo IJ, Lee HP, Yoon J, Son DJ, Han SB, and Hong JT
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[This corrects the article e22 in vol. 21, PMID: 34277112.]., (Copyright © 2024. The Korean Association of Immunologists.)
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- 2024
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7. TNF receptor 2 knockout mouse had reduced lung cancer growth and schizophrenia-like behavior through a decrease in TrkB-dependent BDNF level.
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Yeo IJ, Yu JE, Kim SH, Kim DH, Jo M, Son DJ, Yun J, Han SB, and Hong JT
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- Animals, Humans, Mice, A549 Cells, Male, Behavior, Animal drug effects, Cell Proliferation drug effects, Mice, Inbred C57BL, Membrane Glycoproteins genetics, Membrane Glycoproteins metabolism, Brain-Derived Neurotrophic Factor metabolism, Brain-Derived Neurotrophic Factor genetics, Mice, Knockout, Lung Neoplasms pathology, Lung Neoplasms metabolism, Lung Neoplasms genetics, Schizophrenia metabolism, Schizophrenia genetics, Receptors, Tumor Necrosis Factor, Type II metabolism, Receptors, Tumor Necrosis Factor, Type II genetics, Receptors, Tumor Necrosis Factor, Type II deficiency, Receptor, trkB metabolism, Receptor, trkB genetics
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The relationship between schizophrenia (SCZ) and cancer development remains controversial. Based on the disease-gene association platform, it has been revealed that tumor necrosis factor receptor (TNFR) could be an important mediatory factor in both cancer and SCZ development. TNF-α also increases the expression of brain-derived neurotrophic factor (BDNF) and tropomyosin receptor kinase B (TrkB) in the development of SCZ and tumor, but the role of TNFR in mediating the association between the two diseases remains unclear. We studied the vital roles of TNFR2 in the progression of tumor and SCZ-like behavior using A549 lung cancer cell xenografted TNFR2 knockout mice. TNFR2 knockout mice showed significantly decreased tumor size and weight as well as schizophrenia-like behaviors compared to wild-type mice. Consistent with the reduced tumor growth and SCZ-like behaviors, the levels of TrkB and BDNF expression were significantly decreased in the lung tumor tissues and pre-frontal cortex of TNFR2 knockout mice. However, intravenous injection of BDNF (160 μg/kg) to TNFR2 knockout mice for 4 weeks increased tumor growth and SCZ-like behaviors as well as TrkB expression. In in vitro study, significantly decreased cell growth and expression of TrkB and BDNF by siTNFR2 transfection were found in A549 lung cancer cells. However, the addition of BDNF (100 ng/ml) into TNFR2 siRNA transfected A549 lung cancer cells recovered cell growth and the expression of TrkB. These results suggest that TNFR2 could be an important factor in mediating the comorbidity between lung tumor growth and SCZ development through increased TrkB-dependent BDNF levels., (© 2024. The Author(s).)
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- 2024
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8. Correction to "Macrocyclic Immunoproteasome Inhibitors as a Potential Therapy for Alzheimer's Disease".
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Lee MJ, Bhattarai D, Jang H, Baek A, Yeo IJ, Lee S, Miller Z, Lee S, Hong JT, Kim DE, Lee W, and Kim KB
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- 2024
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9. Significance of chitinase-3-like protein 1 in the pathogenesis of inflammatory diseases and cancer.
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Yu JE, Yeo IJ, Han SB, Yun J, Kim B, Yong YJ, Lim YS, Kim TH, Son DJ, and Hong JT
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- Humans, Chitinase-3-Like Protein 1 genetics, Inflammation metabolism, Cytokines, Chitinases, Neoplasms genetics, Neoplasms metabolism
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Chitinase-3-like protein 1 (CHI3L1) is a secreted glycoprotein that mediates inflammation, macrophage polarization, apoptosis, and carcinogenesis. The expression of CHI3L1 is strongly upregulated by various inflammatory and immunological diseases, including several cancers, Alzheimer's disease, and atherosclerosis. Several studies have shown that CHI3L1 can be considered as a marker of disease diagnosis, prognosis, disease activity, and severity. In addition, the proinflammatory action of CHI3L1 may be mediated via responses to various proinflammatory cytokines, including tumor necrosis factor-α, interleukin-1β, interleukin-6, and interferon-γ. Therefore, CHI3L1 may contribute to a vast array of inflammatory diseases. However, its pathophysiological and pharmacological roles in the development of inflammatory diseases remain unclear. In this article, we review recent findings regarding the roles of CHI3L1 in the development of inflammatory diseases and suggest therapeutic approaches that target CHI3L1., (© 2023. The Author(s).)
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- 2024
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10. Presenilin-2 knock-In mice show severe depressive behavior via DVL3 downregulation.
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Yoo SS, Lee DW, Ham HJ, Yeo IJ, Chang JY, Yun J, Son DJ, Han SB, and Hong JT
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- Animals, Mice, Dishevelled Proteins metabolism, Down-Regulation, Glycogen Synthase Kinase 3 beta, Hydrocortisone, Mice, Transgenic, Presenilin-1 genetics, Presenilin-2 metabolism, Alzheimer Disease metabolism, Amyloid beta-Peptides metabolism
- Abstract
Introduction: Alzheimer's disease (AD) is the most common form of dementia. Depression is one of the most critical psychiatric complications of AD, and 20%-30% of patients with AD experience symptoms of depression. Phospho-glycogen synthase kinase-3 beta (GSK3β) is known to be associated with AD and depression. Furthermore, the role of disheveled (DVL) is known to regulate GSK3β. Moreover, presenilin-2 (PS2) and DVL have cross-talk with each other. Also, it is widely hypothesized that stress leads to hypersecretion of cortisol and is thus associated with depression. Dickkopf WNT signaling pathway inhibitor-1 (DKK-1) is a crucial factor regulating depression and both amyloid beta (Aβ) and phosphorylation of tau are widely known as a biomarker of AD., Methods: To investigate the relationship between AD and depression, and possible pathways connecting the two diseases, we examined memory function and depression-related behavior test results in PS2 knock-in AD mice (PS2 MT). Next, we confirmed that there are relationships between DVL, depression, and cognitive disease through the comparative toxicogenomics database (https://ctdbase.org) and STRING (https://string-db.org) database., Results: PS2 knock-in mice showed much more severe memory impairment and depression than PS2 wild-type mice (PS2 WT). In AD-related behavioral experiments, PS2 MT mice showed more memory dysfunction compared with PS2 WT group mice. Moreover, Aβ and phosphorylation of tau showed higher expression in PS2 MT mice than in PS2 WT mice. Depression-related behavioral tests showed that PS2 MT mice exhibited more depressive behaviors than PS2 WT mice. Furthermore, both higher cortisol levels and higher expression of DKK-1 were found in PS2 MT mice relative to PS2 WT mice. The results indicated that there is a relationship between DVL and the release of AD-related mediators and expression of the depression-related glucocorticoid receptor and DKK-1. In the PS2 knock-in group, DVL was significantly decreased compared with the PS2 WT group., Conclusion: Depression increases the risk of developing AD and other forms of dementia. Recent evidence indicates that depression symptoms could trigger changes in memory and thinking over time. However, it is recognized that there are no drugs to facilitate a full recovery for both AD and depression. However, our results suggest that AD and depression could be associated, and DVL could be a significant target for the association between AD and depression., (© 2023 The Authors. CNS Neuroscience & Therapeutics Published by John Wiley & Sons Ltd.)
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- 2024
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11. (E)-2-methoxy-4-(3-(4-methoxyphenyl)prop-1-en-1-yl)phenol alleviates inflammatory responses in LPS-induced mice liver sepsis through inhibition of STAT3 phosphorylation.
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Kim B, Yu JE, Yeo IJ, Son DJ, Lee HP, Roh YS, Lim KH, Yun J, Park H, Han SB, and Hong JT
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- Mice, Animals, Lipopolysaccharides pharmacology, Phenol metabolism, Phenol pharmacology, Phosphorylation, STAT3 Transcription Factor metabolism, Phenols pharmacology, Phenols therapeutic use, Liver metabolism, Signal Transduction, Sepsis chemically induced, Sepsis drug therapy, Sepsis metabolism
- Abstract
Sepsis is a life-threatening disease with limited treatment options, and the inflammatory process represents an important factor affecting its progression. Many studies have demonstrated the critical roles of signal transducer and activator of transcription 3 (STAT3) in sepsis pathophysiology and pro-inflammatory responses. Inhibition of STAT3 activity may therefore represent a promising treatment option for sepsis. We here used a mouse model to demonstrate that (E)-2-methoxy-4-(3-(4-methoxyphenyl)prop-1-en-1-yl)phenol (MMPP) treatment prevented the liver sepsis-related mortality induced by 30 mg/kg lipopolysaccharide (LPS) treatment and reduced LPS-induced increase in alanine transaminase, aspartate transaminase, and lactate dehydrogenase levels, all of which are markers of liver sepsis progression. These recovery effects were associated with decreased LPS-induced STAT3, p65, and JAK1 phosphorylation and proinflammatory cytokine (interleukin 1 beta, interleukin 6, and tumor necrosis factor alpha) level; expression of cyclooxygenase-2 and induced nitric oxide synthase were also reduced by MMPP. In an in vitro study using the normal liver cell line THLE-2, MMPP treatment prevented the LPS-induced increase of STAT3, p65, and JAK1 phosphorylation and inflammatory protein expression in a dose-dependent manner, and this effect was enhanced by combination treatment with MMPP and STAT3 inhibitor. The results clearly indicate that MMPP treatment prevents LPS-induced mortality by inhibiting the inflammatory response via STAT3 activity inhibition. Thus, MMPP represents a novel agent for alleviating LPS-induced liver sepsis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)
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- 2023
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12. Side-Chain Immune Oxysterols Induce Neuroinflammation by Activating Microglia.
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Son Y, Yeo IJ, Hong JT, Eo SK, Lee D, and Kim K
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- Animals, Mice, Neuroinflammatory Diseases, Macrophages metabolism, Brain metabolism, Microglia metabolism, Oxysterols metabolism
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In individuals with Alzheimer's disease, the brain exhibits elevated levels of IL-1β and oxygenated cholesterol molecules (oxysterols). This study aimed to investigate the effects of side-chain oxysterols on IL-1β expression using HMC3 microglial cells and ApoE-deficient mice. Treatment of HMC3 cells with 25-hydroxycholesterol (25OHChol) and 27-hydroxycholesterol (27OHChol) led to increased IL-1β expression at the transcript and protein levels. Additionally, these oxysterols upregulated the surface expression of MHC II, a marker of activated microglia. Immunohistochemistry performed on the mice showed increased microglial expression of IL-1β and MHC II when fed a high-cholesterol diet. However, cholesterol and 24s-hydroxycholesterol did not increase IL-1β transcript levels or MHC II expression. The extent of IL-1β increase induced by 25OHChol and 27OHChol was comparable to that caused by oligomeric β-amyloid, and the IL-1β expression induced by the oxysterols was not impaired by polymyxin B, which inhibited lipopolysaccharide-induced IL-1β expression. Both oxysterols enhanced the phosphorylation of Akt, ERK, and Src, and inhibition of these kinase pathways with pharmacological inhibitors suppressed the expression of IL-1β and MHC II. The pharmacological agents chlorpromazine and cyclosporin A also impaired the oxysterol-induced expression of IL-1β and upregulation of MHC II. Overall, these findings suggest that dysregulated cholesterol metabolism leading to elevated levels of side-chain oxysterols, such as 25OHChol and 27OHChol, can activate microglia to secrete IL-1β through a mechanism amenable to pharmacologic intervention. The activation of microglia and subsequent neuroinflammation elicited by the immune oxysterols can contribute to the development of neurodegenerative diseases.
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- 2023
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13. CHI3L1 induces autophagy through the JNK pathway in lung cancer cells.
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Hong DE, Yu JE, Yoo SS, Yeo IJ, Son DJ, Yun J, Han SB, and Hong JT
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- Mice, Animals, Humans, Cell Line, Tumor, Autophagy, Lung pathology, Autophagy-Related Proteins metabolism, Chitinase-3-Like Protein 1 metabolism, MAP Kinase Signaling System, Lung Neoplasms pathology
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CHI3L1 is closely related to the molecular mechanisms of cancer cell migration, growth, and death. According to recent research, autophagy regulates tumor growth during various stages of cancer development. This study examined the association between CHI3L1 and autophagy in human lung cancer cells. In CHI3L1-overexpressing lung cancer cells, the expression of LC3, an autophagosome marker, and the accumulation of LC3 puncta increased. In contrast, CHI3L1 depletion in lung cancer cells decreased the formation of autophagosomes. Additionally, CHI3L1 overexpression promoted the formation of autophagosomes in various cancer cell lines: it also increased the co-localization of LC3 and the lysosome marker protein LAMP-1, indicating an increase in the production of autolysosomes. In mechanism study, CHI3L1 promotes autophagy via activation of JNK signaling. JNK may be crucial for CHI3L1-induced autophagy since pretreatment with the JNK inhibitor reduced the autophagic effect. Consistent with the in vitro model, the expression of autophagy-related proteins was downregulated in the tumor tissues of CHI3L1-knockout mice. Furthermore, the expression of autophagy-related proteins and CHI3L1 increased in lung cancer tissues compared with normal lung tissues. These findings show that CHI3L1-induced autophagy is triggered by JNK signals and that CHI3L1-induced autophagy could be a novel therapeutic approach to lung cancer., (© 2023. The Author(s).)
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- 2023
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14. Induction of ER stress-mediated apoptosis through SOD1 upregulation by deficiency of CHI3L1 inhibits lung metastasis.
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Yu JE, Yeo IJ, Yoo SS, Kim SH, Son DJ, Yun J, Han SB, and Hong JT
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- Animals, Mice, Apoptosis, Chromatography, Liquid, Endoplasmic Reticulum Stress genetics, Molecular Chaperones metabolism, Tandem Mass Spectrometry, Up-Regulation, Humans, Neoplasm Metastasis, eIF-2 Kinase genetics, eIF-2 Kinase metabolism, Lung Neoplasms genetics, Superoxide Dismutase-1 metabolism, Chitinase-3-Like Protein 1 genetics
- Abstract
Chitinase-3-like protein 1 (CHI3L1), which is secreted by immune and inflammatory cells, is associated with several inflammatory diseases. However, the basic cellular pathophysiological functions of CHI3L1 are not well characterized. To investigate the novel pathophysiological function of CHI3L1, we performed LC-MS/MS analysis of cells transfected with Myc-vector and Myc-CHI3L1. We analyzed the changes in the protein distribution in Myc-CHI3L1 transfected-cells, and identified 451 differentially expressed proteins (DEPs) compared with Myc-vector-transfected-cells. The biological function of the 451 DEPs was analyzed and it was found that the proteins with endoplasmic reticulum (ER)-associated function were much more highly expressed in CHI3L1-overexpressing cells. We then compared and analyzed the effect of CHI3L1 on the ER chaperon levels in normal lung cells and cancer cells. We identified that CHI3L1 is localized in the ER. In normal cells, the depletion of CHI3L1 did not induce ER stress. However, the depletion of CHI3L1 induces ER stress and eventually activates the unfolded protein response, especially the activation of Protein kinase R-like endoplasmic reticulum kinase (PERK), which regulates protein synthesis in cancer cells. CHI3L1 may not affect ER stress owing to the lack of misfolded proteins in normal cells, but instead activate ER stress as a defense mechanism only in cancer cells. Under ER stress conditions induced by the application of thapsigargin, the depletion of CHI3L1 induces ER stress through the upregulation of PERK and PERK downstream factors (eIF2α and ATF4) in both normal and cancer cells. However, these signaling activations occur more often in cancer cells than in normal cells. The expression of Grp78 and PERK in the tissues of patients with lung cancer was higher compared with healthy tissues. It is well known that ER stress-mediated PERK-eIF2α-ATF4 signaling activation causes apoptotic cell death. ER stress-mediated apoptosis induced by the depletion of CHI3L1 occurs in cancer cells, but rarely occurs in normal cells. Consistent with results from the in vitro model, ER stress-mediated apoptosis was greatly increased during tumor growth and in the lung metastatic tissue of CHI3L1-knockout (KO) mice. The analysis of "big data" identified superoxide dismutase-1 (SOD1) as a novel target of CHI3L1 and interacted with CHI3L1. The depletion of CHI3L1 increased SOD1 expression, resulting in ER stress. Furthermore, the depletion of SOD1 reduced the expression of ER chaperones and ER-mediated apoptotic marker proteins, as well as apoptotic cell death induced by the depletion of CHI3L1 in in vivo and in vitro models. These results suggest that the depletion of CHI3L1 increases ER stress-mediated apoptotic cell death through SOD1 expression, and subsequently inhibits lung metastasis., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)
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- 2023
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15. Overexpression of transmembrane TNFα in brain endothelial cells induces schizophrenia-relevant behaviors.
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Yeo IJ, Yun J, Son DJ, Han SB, Webster MJ, Hong JT, and Kim S
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- Mice, Animals, Tumor Necrosis Factor-alpha genetics, Tumor Necrosis Factor-alpha metabolism, Endothelial Cells metabolism, Receptors, Tumor Necrosis Factor, Type II metabolism, Brain metabolism, Inflammation genetics, Schizophrenia metabolism, Methamphetamine
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Upregulation of genes and coexpression networks related to immune function and inflammation have been repeatedly reported in the brain of individuals with schizophrenia. However, a causal relationship between the abnormal immune/inflammation-related gene expression and schizophrenia has not been determined. We conducted co-expression networks using publicly available RNA-seq data from prefrontal cortex (PFC) and hippocampus (HP) of 64 individuals with schizophrenia and 64 unaffected controls from the SMRI tissue collections. We identified proinflammatory cytokine, transmembrane tumor necrosis factor-α (tmTNFα), as a potential regulator in the module of co-expressed genes that we find related to the immune/inflammation response in endothelial cells (ECs) and/or microglia of the brain of individuals with schizophrenia. The immune/inflammation-related modules associated with schizophrenia and the TNF signaling pathway that regulate the network were replicated in an independent cohort of brain samples from 68 individuals with schizophrenia and 135 unaffected controls. To investigate the association between the overexpression of tmTNFα in brain ECs and schizophrenia-like behaviors, we induced short-term overexpression of the uncleavable form of (uc)-tmTNFα in ECs of mouse brain for 7 weeks. We found schizophrenia-relevant behavioral deficits in these mice, including cognitive impairment, abnormal sensorimotor gating, and sensitization to methamphetamine (METH) induced locomotor activity and METH-induced neurotransmitter levels. These uc-tmTNFα effects were mediated by TNF receptor2 (TNFR2) and induced activation of TNFR2 signaling in astrocytes and neurons. A neuronal module including neurotransmitter signaling pathways was down-regulated in the brain of mice by the short-term overexpression of the gene, while an immune/inflammation-related module was up-regulated in the brain of mice after long-term expression of 22 weeks. Our results indicate that tmTNFα may play a direct role in regulating neurotransmitter signaling pathways that contribute to the clinical features of schizophrenia., (© 2022. The Author(s), under exclusive licence to Springer Nature Limited.)
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- 2023
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16. Snake venom induces an autophagic cell death via activation of the JNK pathway in colorectal cancer cells.
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Yu JE, Yeo IJ, Lee DW, Chang JY, Son DJ, Yun J, Han SB, and Hong JT
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Snake venom contains many proteins that help treat or prevent thrombosis, cardiovascular disease, and cancer, and many studies have been reported in this regard. It has recently been reported that autophagy exerts anticancer effects by inducing tumor cell death and inhibiting cell growth. In this study, we investigated the effect of snake venom on autophagy. Unlike normal colon cells, LC3-II protein levels and LC3 puncta accumulation are increased in snake venom-treated colorectal cancer cells. Inhibition of autophagy by treating cells with hydroxychloroquine, an autophagy inhibitor, prevented snake venom-induced cell death, indicating that snake venom indeed induces autophagic cell death in human colorectal cancer cells. In addition, we demonstrated that activated JNK, and not mTOR signaling, is an upstream effector controlling autophagy. Pretreatment with SP600125, a JNK inhibitor, reversed snake venom-induced autophagy and cell death, indicating that JNK plays a critical role in snake venom-induced autophagy. This study demonstrated that snake venom can function as an anticarcinogenby induction autophagy., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)
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- 2022
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17. Anti-Chi3L1 antibody suppresses lung tumor growth and metastasis through inhibition of M2 polarization.
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Yu JE, Yeo IJ, Son DJ, Yun J, Han SB, and Hong JT
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- Animals, Humans, Inflammation, Mice, Biological Phenomena, Lung Neoplasms pathology
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Chitinase 3-like 1 (Chi3L1) is associated with various biological processes, such as inflammation, tissue repair, proliferation, cell survival, invasion, and extracellular matrix remodeling. Recent studies indicated that Chi3L1 is critical for cancer development and metastasis. In this study, we demonstrate that Chi3L1 serum and tissue levels were significantly increased in lung cancer patients compared with controls. We previously developed an anti-Chi3L1-humanized antibody, and here, we investigate its antitumor and antimetastatic effect. The anti-Chi3L1 antibody attenuated tumor growth and metastasis both in vitro and in vivo in a lung cancer mouse model. These inhibitory effects are associated with signal transducer and activator of transcription 6 (STAT6)-dependent M2 polarization inhibition. Proteomics analysis revealed that plasminogen (PLG) interacts with Chi3L1 and affects M2 polarization. Chi3L1 plays a critical role in lung cancer progression, and the anti-Chi3L1 antibody could be a new anticancer therapy., (© 2021 The Authors. Molecular Oncology published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.)
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- 2022
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18. Corrigendum: Inhibition of Lung Tumor Development in ApoE Knockout Mice via Enhancement of TREM-1 Dependent NK Cell Cytotoxicity.
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Lee YS, Yeo IJ, Kim KC, Han SB, and Hong JT
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[This corrects the article DOI: 10.3389/fimmu.2019.01379.]., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Lee, Yeo, Kim, Han and Hong.)
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- 2022
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19. Botulinum Toxin A Ameliorates Neuroinflammation in the MPTP and 6-OHDA-Induced Parkinson's Disease Models.
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Ham HJ, Yeo IJ, Jeon SH, Lim JH, Yoo SS, Son DJ, Jang SS, Lee H, Shin SJ, Han SB, Yun JS, and Hong JT
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Recently, increasing evidence suggests that neuroinflammation may be a critical factor in the development of Parkinson's disease (PD) in addition to the ratio of acetylcholine/dopamine because dopaminergic neurons are particularly vulnerable to inflammatory attack. In this study, we investigated whether botulinum neurotoxin A (BoNT-A) was effective for the treatment of PD through its anti-neuroinflammatory effects and the modulation of acetylcholine and dopamine release. We found that BoNT-A ameliorated MPTP and 6-OHDA-induced PD progression, reduced acetylcholine release, levels of IL-1β, IL-6 and TNF-α as well as GFAP expression, but enhanced dopamine release and tyrosine hydroxylase expression. These results indicated that BoNT-A had beneficial effects on MPTP or 6-OHDA-induced PD-like behavior impairments via its anti-neuroinflammation properties, recovering dopamine, and reducing acetylcholine release.
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- 2022
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20. Macrocyclic Immunoproteasome Inhibitors as a Potential Therapy for Alzheimer's Disease.
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Lee MJ, Bhattarai D, Jang H, Baek A, Yeo IJ, Lee S, Miller Z, Lee S, Hong JT, Kim DE, Lee W, and Kim KB
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- Alzheimer Disease metabolism, Animals, Cells, Cultured, Dose-Response Relationship, Drug, Humans, Macrocyclic Compounds chemical synthesis, Macrocyclic Compounds chemistry, Mice, Mice, Inbred C57BL, Mice, Transgenic, Molecular Structure, Proteasome Inhibitors chemical synthesis, Proteasome Inhibitors chemistry, Structure-Activity Relationship, Alzheimer Disease drug therapy, Macrocyclic Compounds pharmacology, Proteasome Endopeptidase Complex metabolism, Proteasome Inhibitors pharmacology
- Abstract
Previously, we reported that immunoproteasome (iP)-targeting linear peptide epoxyketones improve cognitive function in mouse models of Alzheimer's disease (AD) in a manner independent of amyloid β. However, these compounds' clinical prospect for AD is limited due to potential issues, such as poor brain penetration and metabolic instability. Here, we report the development of iP-selective macrocyclic peptide epoxyketones prepared by a ring-closing metathesis reaction between two terminal alkenes attached at the P2 and P3/P4 positions of linear counterparts. We show that a lead macrocyclic compound DB-60 ( 20 ) effectively inhibits the catalytic activity of iP in ABCB1-overexpressing cells (IC
50 : 105 nM) and has metabolic stability superior to its linear counterpart. DB-60 ( 20 ) also lowered the serum levels of IL-1α and ameliorated cognitive deficits in Tg2576 mice. The results collectively suggest that macrocyclic peptide epoxyketones have improved CNS drug properties than their linear counterparts and offer promising potential as an AD drug candidate.- Published
- 2021
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21. Amyloidogenic, neuroinflammatory and memory dysfunction effects of HIV-1 gp120.
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Lee YJ, Yeo IJ, Choi DY, Yun J, Son DJ, Han SB, and Hong JT
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- Amyloidogenic Proteins metabolism, Animals, Brain immunology, Brain virology, HIV Envelope Protein gp120 administration & dosage, HIV Infections immunology, HIV Infections virology, HIV-1 metabolism, HIV-1 pathogenicity, Humans, Infusions, Intraventricular, Male, Memory Disorders immunology, Memory Disorders pathology, Mice, Mice, Inbred ICR, Neuroinflammatory Diseases immunology, Neuroinflammatory Diseases pathology, Brain pathology, HIV Envelope Protein gp120 metabolism, HIV Infections complications, Memory Disorders virology, Neuroinflammatory Diseases virology
- Abstract
Human immunodeficiency virus 1 (HIV-1) infection can cause several HIV-associated neurocognitive disorders a variety of neurological impairments characterized by the loss of cortical and subcortical neurons and decreased cognitive and motor function. HIV-1 gp120, the major envelope glycoprotein on viral particles, acts as a binding protein for viral entry and is known to be an agent of neuronal cell death. To determine the mechanism of HIV-1 gp120-induced memory dysfunction, we performed mouse intracerebroventricular (i.c.v.) infusion with HIV-1 gp120 protein (300 ng per mouse) and investigated memory impairment and amyloidogenesis. Infusion of the HIV-1 gp120 protein induced memory dysfunction, which was evaluated using passive avoidance and water maze tests. Infusion of HIV-1 gp120 induced neuroinflammation, such as the release of iNOS and COX-2 and the activation of astrocytes and microglia and increased the mRNA and protein levels of IL-6, ICAM-1, M-CSF, TIM, and IL-2. In particular, we found that the infusion of HIV-1 gp120 induced the accumulation of amyloid plaques and signs of elevated amyloidogenesis, such as increased expression of amyloid precursor protein and BACE1 and increased β-secretase activity. Therefore, these studies suggest that HIV-1 gp120 may induce memory impairment through Aβ accumulation and neuroinflammation., (© 2021. The Author(s).)
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- 2021
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22. Inhibition of Chitinase-3-like-1 by K284-6111 Reduces Atopic Skin Inflammation via Repressing Lactoferrin.
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Jeon SH, Lee YS, Yeo IJ, Lee HP, Yoon J, Son DJ, Han SB, and Hong JT
- Abstract
Chitinase-3-like-1 (CHI3L1) is known to induce inflammation in the progression of allergic diseases. Previous our studies revealed that 2-({3-[2-(1-cyclohexen-1-yl)ethyl]-6,7-dimethoxy-4-oxo-3,4-dihydro-2-quinazolinyl}sulfanyl)-N-(4-ethylphenyl)butanamide (K284-6111; K284), the CHI3L1 inhibiting compound, has the anti-inflammatory effect on neuroinflammation. In this study, we investigated that K284 treatment could inhibit the development of atopic dermatitis (AD). To identify the effect of K284, we used phthalic anhydride (5% PA)-induced AD animal model and in vitro reconstructed human skin model. We analyzed the expression of AD-related cytokine mediators and NF-κB signaling by Western blotting, ELISA and quantitative real-time PCR. Histological analysis showed that K284 treatment suppressed PA-induced epidermal thickening and infiltration of mast cells. K284 treatment also reduced PA-induced release of inflammatory cytokines. In addition, K284 treatment inhibited the expression of NF-κB activity in PA-treated skin tissues and TNF-α and IFN-γ-treated HaCaT cells. Protein-association network analysis indicated that CHI3L1 is associated with lactoferrin (LTF). LTF was elevated in PA-treated skin tissues and TNF-α and IFN-γ-induced HaCaT cells. However, this expression was reduced by K284 treatment. Knockdown of LTF decreased the expression of inflammatory cytokines in TNF-α and IFN-γ-induced HaCaT cells. Moreover, anti-LTF antibody treatment alleviated AD development in PA-induced AD model. Our data demonstrate that CHI3L1 targeting K284 reduces AD-like skin inflammation and K284 could be a promising therapeutic agent for AD by inhibition of LTF expression., Competing Interests: Conflict of Interest: The authors declare no potential conflicts of interest., (Copyright © 2021. The Korean Association of Immunologists.)
- Published
- 2021
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23. Antifungal drug miconazole ameliorated memory deficits in a mouse model of LPS-induced memory loss through targeting iNOS.
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Yeo IJ, Yun J, Son DJ, Han SB, and Hong JT
- Subjects
- Animals, Antifungal Agents pharmacology, Astrocytes drug effects, Astrocytes metabolism, Brain pathology, Cell Nucleus drug effects, Cell Nucleus metabolism, Cells, Cultured, Cytokines biosynthesis, Disease Models, Animal, Inflammation complications, Inflammation pathology, Lipopolysaccharides, Male, Memory Disorders complications, Mice, Inbred C57BL, Miconazole pharmacology, Microglia drug effects, Microglia metabolism, NF-KappaB Inhibitor alpha metabolism, Nitric Oxide Synthase Type II antagonists & inhibitors, Phosphorylation drug effects, Protein Subunits metabolism, Protein Transport drug effects, Rats, Antifungal Agents therapeutic use, Memory Disorders drug therapy, Memory Disorders enzymology, Miconazole therapeutic use, Nitric Oxide Synthase Type II metabolism
- Abstract
Alzheimer's disease (AD) is closely related to neuroinflammation, and the increase in inflammatory cytokine generation and inducible nitric oxide synthase (iNOS) expression in the brain of a patient with AD is well known. Excessive cytokines can stimulate iNOS in microglia and astroglia and overproduce nitric oxide, which can be toxic to neurons. The disease-gene-drug network analysis based on the GWAS/OMIM/DEG records showed that miconazole (MCZ) affected AD through interactions with NOS. Inhibiting iNOS can reduce neuroinflammation, thus preventing AD progression. To investigate the prophylactic role of antifungal agent in the AD development, a lipopolysaccharide-induced memory disorder mouse model was used, and cognitive function was assessed by Morris water maze test and passive avoidance test. MCZ treatment significantly attenuated cognitive impairment, suppressed iNOS and cyclooxygenase-2 expression, and activation of astrocyte and microglial BV2 cells, as well as reduced cytokine levels in the brains and lipopolysaccharide-treated astrocytes and microglia BV2 cells. In further mechanism studies, Pull-down assay and iNOS luciferase activity data showed that MCZ binds to iNOS and inhibited transcriptional activity. Our results suggest that MCZ is useful for ameliorating the neuroinflammation-mediated AD progression by blocking iNOS expression.
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- 2020
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24. LMP2 Inhibitors as a Potential Treatment for Alzheimer's Disease.
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Bhattarai D, Lee MJ, Baek A, Yeo IJ, Miller Z, Baek YM, Lee S, Kim DE, Hong JT, and Kim KB
- Subjects
- Animals, Cell Line, Transformed, Cysteine Proteinase Inhibitors chemical synthesis, Cysteine Proteinase Inhibitors toxicity, Epithelial-Mesenchymal Transition drug effects, Humans, Interleukin-1alpha metabolism, Mice, Transgenic, Microglia drug effects, Molecular Structure, Nootropic Agents chemical synthesis, Nootropic Agents toxicity, Oligopeptides chemical synthesis, Oligopeptides toxicity, Small Molecule Libraries chemical synthesis, Small Molecule Libraries therapeutic use, Small Molecule Libraries toxicity, Structure-Activity Relationship, Alzheimer Disease drug therapy, Cysteine Endopeptidases metabolism, Cysteine Proteinase Inhibitors therapeutic use, Nootropic Agents therapeutic use, Oligopeptides therapeutic use
- Abstract
The immunoproteasome (iP), an inducible proteasome variant harboring three immunosubunits, low molecular mass polypeptide-2 (LMP2), multicatalytic endopeptidase complex subunit-1, and low molecular mass polypeptide-7 (LMP7), is involved in multiple facets of inflammatory responses. We recently reported that YU102, a dual inhibitor of the iP subunit LMP2 and the constitutive proteasome catalytic subunit β1, ameliorates cognitive impairments in mouse models of Alzheimer's disease (AD) independently of amyloid deposits. To investigate whether inhibition of LMP2 is sufficient to improve the cognitive functions of AD mice, here we prepared 37 YU102 analogues and identified a potent LMP2 inhibitor DB-310 ( 28 ) (IC
50 : 80.6 nM) with improved selectivity and permeability in cells overexpressing ABCB1 transporters. We show that DB-310 induces suppression of IL-1α production in microglia cells and improves cognitive functions in the Tg2576 transgenic mouse model of AD. This study supports that inhibition of LMP2 is a promising therapeutic strategy for treatment of AD.- Published
- 2020
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25. Prevention of multiple system atrophy using human bone marrow-derived mesenchymal stem cells by reducing polyamine and cholesterol-induced neural damages.
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Park KR, Hwang CJ, Yun HM, Yeo IJ, Choi DY, Park PH, Kim HS, Lee JT, Jung YS, Han SB, and Hong JT
- Subjects
- Animals, Humans, Male, Multiple System Atrophy pathology, Rats, Rats, Sprague-Dawley, Rats, Wistar, Bone Marrow Cells metabolism, Cholesterol adverse effects, Mesenchymal Stem Cells metabolism, Multiple System Atrophy prevention & control, Multiple System Atrophy therapy, Polyamines adverse effects
- Abstract
Background: Multiple system atrophy (MSA) is a sporadic neurodegenerative disorder of unknown etiology, but is closely associated with damage to dopaminergic neurons. MSA progression is rapid. Hence, long-term drug treatments do not have any therapeutic benefits. We assessed the inhibitory effect of mesenchymal stem cells (MSCs) on double-toxin-induced dopaminergic neurodegenerative MSA., Results: Behavioral disorder was significantly improved and neurodegeneration was prevented following MSC transplantation. Proteomics revealed lower expression of polyamine modulating factor-binding protein 1 (PMFBP1) and higher expression of 3-hydroxymethyl-3-methylglutaryl-CoA lyase (HMGCL), but these changes were reversed after MSC transplantation. In the in vitro study, the 6-OHDA-induced effects were reversed following co-culture with MSC. However, PMFBP1 knockdown inhibited the recovery effect due to the MSCs. Furthermore, HMGCL expression was decreased following co-culture with MSCs, but treatment with recombinant HMGCL protein inhibited the recovery effects due to MSCs., Conclusions: These data indicate that MSCs protected against neuronal loss in MSA by reducing polyamine- and cholesterol-induced neural damage.
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- 2020
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26. PEGylated Erythropoietin Protects against Brain Injury in the MCAO-Induced Stroke Model by Blocking NF-κB Activation.
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Im JH, Yeo IJ, Hwang CJ, Lee KS, and Hong JT
- Abstract
Cerebral ischemia exhibits a multiplicity of pathophysiological mechanisms. During ischemic stroke, the reactive oxygen species (ROS) concentration rises to a peak during reperfusion, possibly underlying neuronal death. Recombinant human erythropoietin (EPO) supplementation is one method of treating neurodegenerative disease by reducing the generation of ROS. We investigated the therapeutic effect of PEGylated EPO (P-EPO) on ischemic stroke. Mice were administered P-EPO (5,000 U/kg) via intravenous injection, and middle cerebral artery occlusion (MCAO) followed by reperfusion was performed to induce in vivo ischemic stroke. P-EPO ameliorated MCAO-induced neurological deficit and reduced behavioral disorder and the infarct area. Moreover, lipid peroxidation, expression of inflammatory proteins (cyclooxygenase-2 and inducible nitric oxide synthase), and cytokine levels in blood were reduced by the P-EPO treatment. In addition, higher activation of nuclear factor kappa B (NF-κB) was found in the brain after MCAO, but NF-κB activation was reduced in the P-EPO-injected group. Treatment with the NF-κB inhibitor PS-1145 (5 mg/kg) abolished the P-EPO-induced reduction of infarct volume, neuronal death, neuroinflammation, and oxidative stress. Moreover, P-EPO was more effective than EPO (5,000 U/kg) and similar to a tissue plasminogen activator (10 mg/kg). An in vitro study revealed that P-EPO (25, 50, and 100 U/mL) treatment protected against rotenone (100 nM)-induced neuronal loss, neuroinflammation, oxidative stress, and NF-κB activity. These results indicate that the administration of P-EPO exerted neuroprotective effects on cerebral ischemia damage through anti-oxidant and anti-inflammatory properties by inhibiting NF-κB activation.
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- 2020
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27. Deletion of Chitinase-3-like 1 accelerates stroke development through enhancement of Neuroinflammation by STAT6-dependent M2 microglial inactivation in Chitinase-3-like 1 knockout mice.
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Im JH, Yeo IJ, Park PH, Choi DY, Han SB, Yun J, and Hong JT
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- Animals, Mice, Mice, Knockout, Signal Transduction physiology, Stroke pathology, Chitinase-3-Like Protein 1 deficiency, Inflammation metabolism, Microglia metabolism, STAT6 Transcription Factor metabolism, Stroke metabolism
- Abstract
Chitinase 3-like 1 (Chi3L1) plays a major role in the pathogenesis of inflammatory diseases. We investigated the effect of Chi3L1 knockout on stroke development. Ischemia/reperfusion was induced by middle cerebral artery occlusion (MCAO) in Chi3L1 knockout and wildtype mice. Significantly increased infarct volume and decreased neurological deficit scores at 24 h after ischemia/reperfusion were found in Chi3L1 knockout mice compared to wildtype mice. Moreover, ischemic neuronal cell death was increased in Chi3L1 knockout mice through increased oxidative stress and release of IL-6 and IL-1β but IL-10 and IL-4 were reduced. Furthermore, expression of inflammation-related proteins (iNOS, COX-2, Iba-1, and GFAP) was significantly increased in Chi3L1 knockout mice compared to wildtype. In microglia isolated from MCAO-injured Chi3L1 knockout mice, expression of M1 markers (iNOS, CD86, IL-1β, and IL-6) was increased and M2 markers (Arg1, Mrc1, IL-10, and IL-4Ra) was decreased. In BV-2 cells, knockdown of Chi3L1 increased TNF-α- and INF-γ-induced expression of iNOS, COX-2, and Iba-1, but decreased the expression of Arg1, MRC1, and IL-4 receptor-alpha (IL-4Rα). Expression of IL-4Rα, an important factor of M2 polarization, and its downstream signals p-JAK1, p-JAK3, and p-STAT6, was much reduced in the knockout mice. Additionally, in BV-2 cells, knockdown of Chi3L1 by siRNA Chi3L1 decreased rhTNF-α- and INF-γ-induced expression of IL-4Rα, p-JAK1, p-JAK3, and p-STAT6. Furthermore, treatment with AS1517499 abolished Chi3L1 knockdown-induced reduced IL-4Rα and Arg1 but not CD86 expression. Our results indicate that deletion of Chi3L1 accelerates stroke development through enhancement of neuroinflammation by markedly decreasing STAT6-dependent M2 macrophage polarization., (Copyright © 2019 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2020
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28. A dual inhibitor of the proteasome catalytic subunits LMP2 and Y attenuates disease progression in mouse models of Alzheimer's disease.
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Yeo IJ, Lee MJ, Baek A, Miller Z, Bhattarai D, Baek YM, Jeong HJ, Kim YK, Kim DE, Hong JT, and Kim KB
- Subjects
- Alzheimer Disease enzymology, Alzheimer Disease genetics, Alzheimer Disease pathology, Amyloid beta-Peptides genetics, Amyloid beta-Peptides metabolism, Animals, Brain enzymology, Brain pathology, Cell Line, Cognitive Dysfunction enzymology, Cognitive Dysfunction genetics, Cognitive Dysfunction pathology, Cysteine Endopeptidases metabolism, Disease Models, Animal, Gene Expression Regulation, Humans, Interleukin-1alpha genetics, Interleukin-1alpha metabolism, Interleukin-6 genetics, Interleukin-6 metabolism, Liver drug effects, Liver enzymology, Liver pathology, Maze Learning drug effects, Mice, Mice, Inbred ICR, Mice, Transgenic, Monocyte Chemoattractant Proteins genetics, Monocyte Chemoattractant Proteins metabolism, Neuroglia enzymology, Neuroglia pathology, Protein Subunits antagonists & inhibitors, Protein Subunits genetics, Protein Subunits metabolism, Spleen drug effects, Spleen enzymology, Spleen pathology, Alzheimer Disease drug therapy, Brain drug effects, Cognitive Dysfunction drug therapy, Cysteine Endopeptidases genetics, Neuroglia drug effects, Proteasome Inhibitors pharmacology
- Abstract
The immunoproteasome (iP) is a variant of the constitutive proteasome (cP) that is abundantly expressed in immune cells which can also be induced in somatic cells by cytokines such as TNF-α or IFN-γ. Accumulating evidence support that the iP is closely linked to multiple facets of inflammatory response, eventually leading to the development of several iP inhibitors as potential therapeutic agents for autoimmune diseases. Recent studies also found that the iP is upregulated in reactive glial cells surrounding amyloid β (Aβ) deposits in brains of Alzheimer's disease (AD) patients, but the role it plays in the pathogenesis of AD remains unclear. In this study, we investigated the effects of several proteasome inhibitors on cognitive function in AD mouse models and found that YU102, a dual inhibitor of the iP catalytic subunit LMP2 and the cP catalytic subunit Y, ameliorates cognitive impairments in AD mouse models without affecting Aβ deposition. The data obtained from our investigation revealed that YU102 suppresses the secretion of inflammatory cytokines from microglial cells. Overall, this study indicates that there may exist a potential link between LMP2/Y and microglia-mediated neuroinflammation and that inhibition of these subunits may offer a new therapeutic strategy for AD.
- Published
- 2019
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29. Roles of chitinase 3-like 1 in the development of cancer, neurodegenerative diseases, and inflammatory diseases.
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Yeo IJ, Lee CK, Han SB, Yun J, and Hong JT
- Subjects
- Animals, Humans, Inflammation drug therapy, Neoplasms drug therapy, Neurodegenerative Diseases drug therapy, Chitinase-3-Like Protein 1 metabolism, Inflammation metabolism, Neoplasms metabolism, Neurodegenerative Diseases metabolism
- Abstract
Chitinase 3-like 1 (CHI3L1) is a secreted glycoprotein that mediates inflammation, macrophage polarization, apoptosis, and carcinogenesis. The expression of CHI3L1 is strongly increased by various inflammatory and immunological conditions, including rheumatoid arthritis, multiple sclerosis, Alzheimer's disease, and several cancers. However, its physiological and pathophysiological roles in the development of cancer and neurodegenerative and inflammatory diseases remain unclear. Several studies have reported that CHI3L1 promotes cancer proliferation, inflammatory cytokine production, and microglial activation, and that multiple receptors, such as advanced glycation end product, syndecan-1/αVβ3, and IL-13Rα2, are involved. In addition, the pro-inflammatory action of CHI3L1 may be mediated via the protein kinase B and phosphoinositide-3 signaling pathways and responses to various pro-inflammatory cytokines, including tumor necrosis factor-α, interleukin-1β, interleukin-6, and interferon-γ. Therefore, CHI3L1 could contribute to a vast array of inflammatory diseases. In this article, we review recent findings regarding the roles of CHI3L1 and suggest therapeutic approaches targeting CHI3L1 in the development of cancers, neurodegenerative diseases, and inflammatory diseases., (Copyright © 2019 Elsevier Inc. All rights reserved.)
- Published
- 2019
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30. Bee venom phospholipase A2 ameliorates amyloidogenesis and neuroinflammation through inhibition of signal transducer and activator of transcription-3 pathway in Tg2576 mice.
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Ham HJ, Han SB, Yun J, Yeo IJ, Ham YW, Kim SH, Park PH, Choi DY, and Hong JT
- Abstract
Background: Neuroinflammation and accumulation of β-amyloid (Aβ) play a significant role in the onset and progression of Alzheimer's disease (AD). Our previous study demonstrated that signal transducer and activator of transcription-3 (STAT3) plays a major role in neuroinflammation and amyloidogenesis., Methods: In the present study, we investigated the inhibitory effect of bee venom phospholipase A2 (bvPLA2) on memory deficiency in Tg2576 mice, which demonstrate genetic characteristics of AD and the mechanism of its action at the cellular and animal level. For in vivo study, we examined the effect of bvPLA2 on improving memory by conducting several behavioral tests with the administration of bvPLA2 (1 mg/kg) to Tg2576 mice. For in vitro study, we examined the effect of bvPLA2 on amyloidogenesis and neuroinflammation by treating bvPLA2 on LPS-activated BV2 cells., Results: We found that bvPLA2 alleviated memory impairment in Tg2576 mice, as demonstrated in the behavioral tests assessing memory. In the bvPLA2-treated group, Aβ, amyloid precursor protein (APP), and β-secretase 1 (BACE1) levels and β-secretase activity were significantly decreased. Expression of pro-inflammatory cytokines and inflammation-related proteins decreased in the brain of bvPLA2-treated group, whereas anti-inflammatory cytokines increased. In addition, bvPLA2 reduced STAT3 phosphorylation in the brains of the bvPLA2-treated group. At the cellular level, bvPLA2 inhibits production of nitric oxide, pro-inflammatory cytokines, and inflammation-related proteins including p-STAT3. Additionally, bvPLA2 inhibits the production of Aβ in cultured BV-2 cells. Results from the docking experiment, pull-down assay, and the luciferase assay show that bvPLA2 directly binds STAT3 and, thus, regulates gene expression levels. Moreover, when the STAT3 inhibitor and bvPLA2 were administered together, the anti-amyloidogenic and anti-inflammatory effects were further enhanced than when they were administered alone., Conclusion: These results suggest that bvPLA2 could restore memory by inhibiting the accumulation of Aβ and inflammatory responses via blockage of STAT3 activity., Competing Interests: Competing interestsThe authors declare that they have no competing interests., (© The Author(s). 2019.)
- Published
- 2019
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31. Combination Effect of Titrated Extract of Centella asiatica and Astaxanthin in a Mouse Model of Phthalic Anhydride-Induced Atopic Dermatitis.
- Author
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Park JH, Yeo IJ, Jang JS, Kim KC, Park MH, Lee HP, Han SB, and Hong JT
- Abstract
Purpose: In our previous study, we demonstrated that both titrated extract of Centella asiatica (TECA) and astaxanthin (AST) have anti-inflammatory effects in a 5% phthalic anhydride (PA) mouse model of atopic dermatitis (AD). The increasing prevalence of AD demands new therapeutic approaches for treating the disease. We investigated the therapeutic efficacy of the ointment form of TECA, AST and a TECA + AST combination in a mouse model of AD to see whether a combination of the reduced doses of 2 compounds could have a synergistic effect., Methods: An AD-like lesion was induced by the topical application of 5% PA to the dorsal ear and back skin of an Hos:HR-1 mouse. After AD induction, TECA (0.5%), AST (0.5%) and the TECA (0.25%) + AST (0.25%) combination ointment (20 μg/cm²) were spread on the dorsum of the ear or back skin 3 times a week for 4 weeks. We evaluated dermatitis severity, histopathological changes and changes in protein expression by Western blotting for inducible nitric oxide synthase (iNOS), cyclocxygenase (COX)-2, and nuclear factor (NF)-κB activity. We also measured the concentrations of tumor necrosis factor (TNF)-α, interleukin (IL)-6 and immunoglobulin E (IgE) in the blood of AD mice by enzyme-linked immunosorbent assay (ELISA)., Results: PA-induced skin morphological changes and ear thickness were significantly reduced by TECA, AST and TECA + AST treatments, but these inhibiting effects were more pronounced in the TECA + AST treatment. TECA, AST and the TECA+AST reatments inhibited the expression of iNOS and COX-2; NF-κB activity; and the release of TNF-α, IL-6 and IgE. However, the TECA+AST treatment showed additive or synergistic effects on AD., Conclusions: Our results demonstrate that the combination of TECA and AST could be a promising therapeutic agent for AD by inhibiting NF-κB signaling., Competing Interests: There are no financial or other issues that might lead to conflict of interest., (Copyright © 2019 The Korean Academy of Asthma, Allergy and Clinical Immunology · The Korean Academy of Pediatric Allergy and Respiratory Disease.)
- Published
- 2019
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32. Inhibition of Lung Tumor Development in ApoE Knockout Mice via Enhancement of TREM-1 Dependent NK Cell Cytotoxicity.
- Author
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Lee YS, Yeo IJ, Kim KC, Han SB, and Hong JT
- Subjects
- A549 Cells, Animals, Cell Line, Tumor, Cell Proliferation genetics, Cell Transformation, Neoplastic genetics, Humans, Lung Neoplasms chemically induced, Mice, Mice, Inbred C57BL, Mice, Knockout, ApoE, Myeloid Progenitor Cells metabolism, Neoplasm Metastasis genetics, Triggering Receptor Expressed on Myeloid Cells-1 antagonists & inhibitors, Urethane toxicity, Apolipoproteins E genetics, Killer Cells, Natural immunology, Lung Neoplasms immunology, T-Box Domain Proteins genetics, Triggering Receptor Expressed on Myeloid Cells-1 metabolism
- Abstract
Apolipoprotein E (ApoE) is known to regulate lipid homeostasis and associated with atherosclerogenesis. Eventhough atherosclerogenesis is associated with tumor development, the role of ApoE in lung tumorigenesis and metastasis is not clear. Thus, the tumor growth and metastasis were compared in WT and ApoE knockout (KO) mice. Urethane-induced lung tumor incidence and B16F10 lung metastasis in ApoE knockout (KO) mice were significantly reduced in comparison to that in WT mice. Knockdown of ApoE expression in lung cancer cells and B16F10 cells also decreased cancer cell growth and metastasis. The inhibitory effect of ApoE KO on tumor development and metastasis was associated with increase of infiltration of NK cells. NK cells derived from ApoE KO mice showed much greater cytotoxicity than those from WT mice. These cytotoxic effect of NK cells derived from ApoE KO mice was associated with higher expression of Granzyme B, Fas Ligand, IFN-γ, TNF-α, NKG2D, NKp46, and DNAM-1 expression. Triggering receptor expressed on myeloid cell (TREM)-1 is a proinflammatory mediator expressed on NK cells, and is known to be associated with NK cell cytotoxicity. Thus, we investigated the role of TREM-1 on ApoE KO mice originated NK cell mediated cytotoxicity for cancer cells. Blockade of TREM-1 expression with a TREM-1 antagonist prevented NK cell-mediated cytotoxicity. TREM-1 antibody recovered cytotoxic effect of NK cells derived from KO mice of T-bet, which upregulating gene for TREM-1. These data indicate that ApoE KO suppressed lung tumor development and metastasis via increase of TREM-1-dependent anti-tumor activity of NK cells.
- Published
- 2019
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33. Peroxiredoxin 6 Inhibits Osteogenic Differentiation and Bone Formation Through Human Dental Pulp Stem Cells and Induces Delayed Bone Development.
- Author
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Park KR, Yun HM, Yeo IJ, Cho S, Hong JT, and Jeong YS
- Subjects
- Bone Regeneration genetics, Cell Proliferation, Cells, Cultured, Gene Expression, Gene Expression Regulation, Developmental, Glutathione Peroxidase metabolism, Group VI Phospholipases A2 metabolism, Humans, Models, Biological, Peroxiredoxin VI metabolism, Signal Transduction, Transforming Growth Factor beta metabolism, Bone Development genetics, Cell Differentiation genetics, Dental Pulp cytology, Osteogenesis genetics, Peroxiredoxin VI genetics, Stem Cells cytology, Stem Cells metabolism
- Abstract
Aims: Peroxiredoxins (PRDXs) are thiol-specific antioxidant enzymes that regulate redox balance that are critical for maintaining the cellular potential for self-renewal and stemness. Stem cell-based regenerative medicine is a promising approach in tissue reconstruction. However, to obtain functional cells for use in clinical applications, stem cell technology still requires improvements. Results: In this study, we found that PRDX6 levels were decreased during osteogenic differentiation in human dental pulp stem cells (hDPSCs). hDPSCs stably expressing Myc-PRDX6 (hDPSC/myc-PRDX6) inhibited cell growth in hDPSCs during osteogenic differentiation and impaired osteogenic phenotypes such as alkaline phosphatase (ALP) activity, mineralized nodule formation, and osteogenic marker genes [ALP and osteocalcin (OCN)]. hDPSC cell lines stably expressing mutant glutathione peroxidase (PRDX6(C47S)) and independent phospholipase A2 (PRDX6(S32A)) were also generated. Each mutant form of PRDX6 abolished the impaired osteogenic phenotypes, the transforming growth factor-β-mediated Smad2 and p38 pathways, and RUNX2 expression. Furthermore, in vivo experiments revealed that hDPSC/myc-PRDX6 suppressed hDPSC-based bone regeneration in calvarial defect mice, and newborn PRDX6 transgenic mice exhibited delayed bone development and reduced RUNX2 expression. Innovation and Conclusion: These findings illuminate the effects of PRDX6 during osteogenic differentiation of hDPSCs, and also suggest that regulating PRDX6 may improve the clinical utility of stem cell-based regenerative medicine for the treatment of bone diseases. Antioxid. Redox Signal. 30, 1969-1982.
- Published
- 2019
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34. Loss of parkin reduces lung tumor development by blocking p21 degradation.
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Park KR, Yun JS, Park MH, Jung YY, Yeo IJ, Nam KT, Kim HD, Song JK, Choi DY, Park PH, Han SB, Yun HM, and Hong JT
- Subjects
- A549 Cells, Animals, Apoptosis, Cell Cycle, Cell Line, Tumor, Cell Survival, Gene Expression Regulation, Neoplastic, HEK293 Cells, Humans, Incidence, Mice, Mice, Inbred C57BL, Mice, Knockout, Proliferating Cell Nuclear Antigen metabolism, Cyclin-Dependent Kinase Inhibitor p21 metabolism, Lung Neoplasms metabolism, Ubiquitin-Protein Ligases metabolism
- Abstract
Several epidemiological studies have demonstrated the reciprocal relationship between the development of cancer and Parkinson's disease (PD). However, the possible mechanisms underlying this relationship remain unclear. To identify this relationship, we first compared lung tumor growth in parkin knockout (KO) mice and wild-type (WT) mice. Parkin KO mice showed decreased lung tumor growth and increased expression of p21, a cell cycle arrester, as compared with WT mice. We also found that parkin interacts with p21, resulting in its degradation; however, parkin KO, knockdown, as well as mutation (R275W or G430D) reduced the degradation of p21. We investigated whether parkin KO increases the association of p21 with proliferating cell nuclear antigen (PCNA) or CDK2 by reducing p21 degradation, and, thus, arresting the cell cycle. The interaction between p21 and PCNA or CDK2 was also enhanced by parkin knockdown, and this increased interaction induced sub G0/G1 arrest, leading to cell death. Therefore, our data indicate that parkin KO reduces the development of lung tumors via cell cycle arrest by blocking the degradation of p21. These findings suggest that PD could be associated with lower lung cancer incidence., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2019
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35. PRDX6 Inhibits Neurogenesis through Downregulation of WDFY1-Mediated TLR4 Signal.
- Author
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Yeo IJ, Park MH, Son DJ, Kim JY, Nam KT, Hyun BK, Kim SY, Jung MH, Song MJ, Chun HO, Lee TH, Han SB, and Hong JT
- Subjects
- Animals, Cell Differentiation, Cell Lineage, Mice, Inbred C57BL, Mice, Transgenic, Neural Stem Cells metabolism, Neuronal Outgrowth, PC12 Cells, Peroxiredoxin VI genetics, Peroxiredoxin VI metabolism, Rats, Toll-Like Receptor 4 genetics, Adaptor Proteins, Signal Transducing metabolism, Down-Regulation genetics, Neurogenesis genetics, Signal Transduction, Toll-Like Receptor 4 metabolism, Vesicular Transport Proteins metabolism
- Abstract
Impaired neurogenesis has been associated with several brain disorders, such as Alzheimer's disease (AD) and Parkinson's disease (PD). The role of peroxiredoxin 6 (PRDX6) in neurodegenerative diseases is very controversial. To demonstrate the role of PRDX6 in neurogenesis, we compared the neurogenesis ability of PRDX6-overexpressing transgenic (Tg) mice and wild-type mice and studied the involved molecular mechanisms. We showed that the neurogenesis of neural stem cells (NSCs) and the expression of the marker protein were lower in PRDX6 Tg-mice than in wild-type mice. To determine the factors involved in PRDX6-related neural stem cell impairment, we performed a microarray experiment. We showed that the expression of WDFY1 was dramatically decreased in PRDX6-Tg mice. Moreover, WDFY1 siRNA decreases the differentiation ability of primary neural stem cells. Interestingly, WDFY1 reportedly recruits the signaling adaptor TIR-domain-containing adapter-inducing interferon-β (TRIF) to toll-like receptors (TLRs); thus, we showed the relationship among TLRs, PRDX6, and WDFY1. We showed that TLR4 was dramatically reduced in PRDX6 Tg mice, and reduced TLR4 expression and neurogenesis was reversed by the introduction of WDFY1 plasmid in the neural stem cells from PRDX6 Tg mice. This study indicated that PRDX6 inhibits the neurogenesis of neural precursor cells through TLR4-dependent downregulation of WDFY1 and suggested that the inhibitory effect of PRDX6 on neurogenesis play a role in the development of neurodegenerative diseases in the PRDX6 overexpressing transgenic mice.
- Published
- 2019
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36. Inhibitory effect of Carnosol on UVB-induced inflammation via inhibition of STAT3.
- Author
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Yeo IJ, Park JH, Jang JS, Lee DY, Park JE, Choi YE, Joo JH, Song JK, Jeon HO, and Hong JT
- Subjects
- Animals, Enzyme-Linked Immunosorbent Assay, Humans, Immunoglobulin E blood, Immunoglobulin E metabolism, Inflammation metabolism, Mice, Mice, Transgenic, STAT3 Transcription Factor metabolism, Abietanes pharmacology, Anti-Inflammatory Agents, Non-Steroidal pharmacology, Inflammation drug therapy, STAT3 Transcription Factor antagonists & inhibitors, Ultraviolet Rays
- Abstract
Ultraviolet B (UVB) irradiation causes sunburn, inflammatory responses, dysregulation of immune function, oxidative stress, DNA damage and photocarcinogenesis on skin. Rosemary (Rosmarinus officinalis L.) has been reported to inhibit inflammation. Carnosol, a major component of Rosemary, has prominent anti-inflammatory effects. However, its protective effect on UVB-induced inflammatory skin responses has not yet been reported. Here, we investigated the effectiveness of carnosol on UVB-induced inflammation. We examined the anti-inflammation effect of topical application of carnosol (0.05 µg/cm
2 ) on UVB (540 mJ/cm2 , for 3 successive days)-induced skin inflammation in HR1 mice. Topical application of carnosol inhibited UVB-induced erythema, epidermal thickness, inflammatory responses in HR1 mice. Carnosol reduced the level of Immunoglobulin-E and IL-1β in blood serum of UVB-induced mice. Carnosol also significantly inhibited the UVB-induced expression of inflammatory marker protein (iNOS and COX-2) in back skin of mice. In addition, carnosol treated skin decreased activation of STAT3, a transcriptional factor regulating inflammatory genes. Our study suggested that carnosol has protective effects on skin inflammatory skin damages by UVB.- Published
- 2019
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37. Deficiency of parkin suppresses melanoma tumor development and metastasis through inhibition of MFN2 ubiquitination.
- Author
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Lee YS, Jung YY, Park MH, Yeo IJ, Im HS, Nam KT, Kim HD, Kang SK, Song JK, Kim YR, Choi DY, Park PH, Han SB, Yun JS, and Hong JT
- Subjects
- Animals, Cell Line, Tumor, Cell Movement drug effects, Gene Expression Regulation, Neoplastic drug effects, Gene Knockout Techniques methods, Gene Regulatory Networks drug effects, Humans, Lung Neoplasms genetics, Lung Neoplasms metabolism, Melanoma genetics, Melanoma metabolism, Mice, RNA, Small Interfering pharmacology, Ubiquitin-Protein Ligases genetics, Ubiquitin-Protein Ligases metabolism, Ubiquitination drug effects, Xenograft Model Antitumor Assays, GTP Phosphohydrolases metabolism, Lung Neoplasms secondary, Lung Neoplasms therapy, Melanoma drug therapy, Mitochondrial Proteins metabolism, RNA, Small Interfering administration & dosage, Ubiquitin-Protein Ligases antagonists & inhibitors
- Abstract
Parkin, a critical gene of Parkinson's disease, is involved in the development of numerous cancers. However, the effect of parkin deficiency on melanoma growth and metastasis has not been reported. We showed that the tumor size and number of surface lung metastases, and expression of tumor growth and metastasis marker proteins were significantly lower in parkin-KO mice than those observed in non-transgenic controls. In an in vitro study, we also showed that parkin siRNA inhibited cell growth and migration of B16F10 and SK-Mel-28 cells. Parkin-specific ubiquitination of mitofusin-2 (MFN2) was decreased in tumors and metastasized lung tissues of parkin-KO mice. Moreover, we showed that parkin directly binds and ubiquitinates MFN2. Knockdown of MFN2 decreased the expression of Bax and apoptotic cell death, but increased that of Bcl2 and apoptotic cancer cell death. However, these effects were reversed by knockdown of parkin. Conversely, inhibitory effects on melanoma growth and migration of parkin siRNA were reversed by MFN2 siRNA. These data indicate that melanoma development was inhibited in parkin-KO mice through maintaining of MFN2 level by inhibition of ubiquitinating ability of parkin., (Copyright © 2018. Published by Elsevier B.V.)
- Published
- 2018
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38. Estrogen deficiency exacerbates Aβ-induced memory impairment through enhancement of neuroinflammation, amyloidogenesis and NF-ĸB activation in ovariectomized mice.
- Author
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Yun J, Yeo IJ, Hwang CJ, Choi DY, Im HS, Kim JY, Choi WR, Jung MH, Han SB, and Hong JT
- Subjects
- Alzheimer Disease metabolism, Amyloid beta-Peptides physiology, Animals, Astrocytes metabolism, Cyclooxygenase 2 metabolism, Estradiol pharmacology, Estrogens deficiency, Estrogens metabolism, Female, Glial Fibrillary Acidic Protein metabolism, Inflammation metabolism, Lipopolysaccharides pharmacology, Memory Disorders physiopathology, Mice, Mice, Inbred ICR, Microglia metabolism, NF-kappa B metabolism, Neuroimmunomodulation immunology, Nitric Oxide Synthase Type II metabolism, Ovariectomy methods, Primary Cell Culture, Signal Transduction drug effects, Amyloid beta-Peptides metabolism, Estrogens physiology, Memory Disorders metabolism
- Abstract
Estrogen is well known to have a preventative effect in Alzheimer's disease (AD) pathology. Several studies have demonstrated that nuclear factor kappa-B (NF-ĸB) can contribute to the effects of estrogen on the development of AD. We investigated whether NF-ĸB affects amyloid-beta (Aβ)-induced memory impairment in an estrogen-lacking condition. In the present study, nine-week-old Institute cancer research (ICR) mice were ovariectomized to block estrogen stimulation. Ten weeks after the ovariectomization, mice were administered with Aβ (300 pmol) via intracerebroventricular (ICV) infusion for 2 weeks. Memory impairment, neuroinflammatory protein expression, and amyloidogenic pathways were then measured. Ovariectomized mice demonstrated severe memory impairment, Aβ accumulation, neprilysin downregulation, and activation of NF-ĸB signaling compared to sham-control mice. In vitro experiments demonstrated that β-estradiol (10 μM) inhibited Aβ (1 μM)-induced neuroinflammation in microglial BV-2 cells and prevented Aβ-induced cell death in primary cultured neuronal cells. As in in vivo experiments, NF-ĸB activation was significantly upregulated in in vitro experiments. Furthermore β-estradiol treatment inhibited NF-ĸB activation in both of microglial BV-2 cells and cultured neuronal cells. These findings suggest that estrogen may protect against memory impairment through the regulation of Aβ accumulation and neurogenic inflammation by inhibiting NF-κB activity., (Copyright © 2018 Elsevier Inc. All rights reserved.)
- Published
- 2018
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39. Astaxanthin alleviated ethanol-induced liver injury by inhibition of oxidative stress and inflammatory responses via blocking of STAT3 activity.
- Author
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Han JH, Ju JH, Lee YS, Park JH, Yeo IJ, Park MH, Roh YS, Han SB, and Hong JT
- Subjects
- Animals, Antioxidants therapeutic use, Aspartate Aminotransferases blood, Chemical and Drug Induced Liver Injury metabolism, Chemical and Drug Induced Liver Injury pathology, Cytokines metabolism, Disease Models, Animal, Ethanol adverse effects, Inflammation metabolism, Inflammation pathology, Liver drug effects, Liver metabolism, Liver pathology, Male, Mice, Phosphorylation drug effects, Reactive Oxygen Species metabolism, Signal Transduction drug effects, Xanthophylls pharmacology, Xanthophylls therapeutic use, Antioxidants pharmacology, Chemical and Drug Induced Liver Injury drug therapy, Inflammation drug therapy, Oxidative Stress drug effects, STAT3 Transcription Factor metabolism
- Abstract
Astaxanthin (AXT) is classified as a xanthophyll carotenoid compound which have broader functions including potent antioxidant, anti-inflammatory and neuroprotective properties. Considerable researches have demonstrated that AXT shows preventive and therapeutic properties against for Diabetes, Osteoarthritis and Rheumatoid Arthritis. However, the protective effect of AXT on liver disease has not yet been reported. In this study, we investigated effects of AXT on ethanol-induced liver injury in chronic plus binge alcohol feeding model. The hepatic steatosis and inflammation induced by ethanol administration were alleviated by AXT. Serum levels of aspartate transaminase and alanine transaminase were decreased in the livers of AXT administrated group. The ethanol-induced expression of cytochrome P450 2E1 (CYP2E1), pro-inflammatory proteins, cytokines, chemokines and reactive oxygen species (ROS) levels were also reduced in the livers of AXT administrated group. Moreover, ethanol-induced infiltration of neutrophils was decreased in the livers of AXT administrated group. Docking model and pull-down assay showed that AXT directly binds to the DNA binding site of STAT3. Moreover, AXT decreased STAT3 phosphorylation in the liver of AXT administration group. Therefore, these results suggest that AXT could prevent ethanol-induced hepatic injury via inhibition of oxidant and inflammatory responses via blocking of STAT3 activity.
- Published
- 2018
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40. K284-6111 prevents the amyloid beta-induced neuroinflammation and impairment of recognition memory through inhibition of NF-κB-mediated CHI3L1 expression.
- Author
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Choi JY, Yeo IJ, Kim KC, Choi WR, Jung JK, Han SB, and Hong JT
- Subjects
- Amyloid beta-Peptides toxicity, Animals, Anti-Inflammatory Agents therapeutic use, Avoidance Learning drug effects, Brain drug effects, Brain metabolism, Cell Line, Transformed, Disease Models, Animal, Drug Administration Schedule, Drug Delivery Systems, Male, Maze Learning drug effects, Memory Disorders chemically induced, Memory Disorders drug therapy, Mice, Mice, Inbred ICR, Microglia drug effects, Microglia pathology, Peptide Fragments toxicity, Quinazolines therapeutic use, Retention, Psychology drug effects, Chitinase-3-Like Protein 1 metabolism, Encephalitis etiology, Encephalitis prevention & control, Memory Disorders complications, NF-kappa B metabolism, Quinazolines pharmacology, Recognition, Psychology drug effects
- Abstract
Background: Alzheimer's disease, which is pathologically characterized by an excessive accumulation of amyloid beta (Aβ) fibrils, is a degenerative brain disease and the most common cause of dementia. In a previous study, it was reported that an increased level of CHI3L1 in plasma was found in AD patients. We investigated the inhibitory effect of 2-({3-[2-(1-cyclohexen-1-yl)ethyl]-6,7-dimethoxy-4-oxo-3,4-dihydro-2-quinazolinyl}sulfanyl)-N-(4-ethylphenyl)butanamide (K284-6111), an inhibitor of chitinase 3 like 1 (CHI3L1), on memory impairment in Aβ
1-42 -infused mice, and microglial BV-2 cells and astrocytes., Methods: We examined whether K284-6111 (3 mg/kg given orally for 4 weeks) prevents amyloidogenesis and memory loss in Aβ1-42 -induced AD mice model. After intracerebroventrical (ICV) infusion of Aβ1-42 for 14 days, the cognitive function was assessed by the Morris water maze test and passive avoidance test. K284-6111 treatment was found to reduce Aβ1-42 -induced memory loss., Results: A memory recovery effect was found to be associated with the reduction of Aβ1-42 -induced expression of inflammatory proteins (iNOS, COX-2, GFAP, and Iba-1) and the suppression of CHI3L1 expression in the brain. Additionally, K284-6111 reduced Aβ1-42 -induced β-secretase activity and Aβ generation. Lipopolysaccharide (LPS)-induced (1 μg/mL) expression of inflammatory (COX-2, iNOS, GFAP, Iba-1) and amyloidogenic proteins (APP, BACE1) were decreased in microglial BV-2 cells and cultured astrocytes by the K284-6111 treatment (0.5, 1, and 2 μM). Moreover, K284-6111 treatment suppressed p50 and p65 translocation into the nucleus, and phosphorylation of IκB in vivo and in vitro., Conclusion: These results suggest that CHI3L1 inhibitor could be an applicable intervention drug in amyloidogenesis and neuroinflammation, thereby preventing memory dysfunction via inhibition of NF-κB.- Published
- 2018
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41. Anti-inflammatory effect of astaxanthin in phthalic anhydride-induced atopic dermatitis animal model.
- Author
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Park JH, Yeo IJ, Han JH, Suh JW, Lee HP, and Hong JT
- Subjects
- Administration, Cutaneous, Animals, Anti-Inflammatory Agents pharmacology, Cell Count, Cyclooxygenase 2 metabolism, Dermatitis, Atopic chemically induced, Dermatitis, Atopic pathology, Disease Models, Animal, Immunoglobulin E blood, Interleukin-1beta blood, Interleukin-6 blood, Lipopolysaccharides pharmacology, Lymph Nodes pathology, Mast Cells, Mice, Nitric Oxide Synthase metabolism, Organ Size, Phthalic Anhydrides, RAW 264.7 Cells, Severity of Illness Index, Tumor Necrosis Factor-alpha blood, Xanthophylls pharmacology, Xanthophylls therapeutic use, Anti-Inflammatory Agents therapeutic use, Dermatitis, Atopic drug therapy, Dermatitis, Atopic metabolism, NF-kappa B metabolism, Signal Transduction drug effects
- Abstract
In this study, we investigated anti-dermatitic effects of astaxanthin (AST) in phthalic anhydride (PA)-induced atopic dermatitis (AD) animal model as well as in vitro model. AD-like lesion was induced by the topical application of 5% PA to the dorsal skin or ear of Hos:HR-1 mouse. After AD induction, 100 μL of 1 mg/mL and 2 mg/mL of AST (10 μg or 20 μg/cm
2 ) was spread on the dorsum of ear or back skin three times a week for four weeks. We evaluated dermatitis severity, histopathological changes and changes in protein expression by Western blotting for inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and nuclear factor-κB (NF-κB) activity. We also measured tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6) and immunoglobulin E (IgE) concentration in the blood of AD mice by enzyme-linked immunosorbent assay (ELISA). AST treatment attenuated the development of PA-induced AD. Histological analysis showed that AST inhibited hyperkeratosis, mast cells and infiltration of inflammatory cells. AST treatment inhibited expression of iNOS and COX-2, and NF-κB activity as well as release of TNF-α, IL-1β, IL-6 and IgE. In addition, AST (5, 10 and 20 μM) potently inhibited lipopolysaccharide (LPS) (1 μg/mL)-induced nitric oxide (NO) production, expression of iNOS and COX-2 and NF-κB DNA binding activities in RAW 264.7 macrophage cells. Our data demonstrated that AST could be a promising agent for AD by inhibition of NF-κB signalling., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)- Published
- 2018
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42. Isolation and Characterization of Pepsin-soluble Collagens from Bones, Skins, and Tendons in Duck Feet.
- Author
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Kim HW, Yeo IJ, Hwang KE, Song DH, Kim YJ, Ham YK, Jeong TJ, Choi YS, and Kim CJ
- Abstract
The objectives of this study were conducted to characterize pepsin-soluble collagen (PSC) extracted from bones (PSC-B), skins (PSC-S), and tendons (PSC-T) of duck feet and to determine their thermal and structural properties, for better practical application of each part of duck feet as a novel source for collagen. PSC was extracted from each part of duck feet by using 0.5 M acetic acid containing 5% (w/w) pepsin. Electrophoretic patterns showed that the ratio between α
1 and α2 chains, which are subunit polypeptides forming collagen triple helix, was approximately 1:1 in all PSCs of duck feet. PSC-B had slightly higher molecular weights for α1 and α2 chains than PSC-S and PSC-T. From the results of differential scanning calorimetry (DSC), higher onset (beginning point of melting) and peak temperatures (maximum point of curve) were found at PSC-B compared to PSC-S and PSC-T ( p <0.05). Fourier transform infrared spectroscopy (FT-IR) presented that PSC-S and PSC-T had similar intermolecular structures and chemical bonds, whereas PSC-B exhibited slight difference in amide A region. Irregular dense sheet-like films linked by random-coiled filaments were observed similarly. Our findings indicate that PSCs of duck feet might be characterized similarly as a mixture of collagen type I and II and suggest that duck feet could be used for collagen extraction without deboning and/or separation processes.- Published
- 2016
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43. Radiographic film dosimetry of proton beams for depth-dose constancy check and beam profile measurement.
- Author
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Yeo IJ, Teran A, Ghebremedhin A, Johnson M, and Patyal B
- Subjects
- Computer Simulation, Equipment Design, Equipment Failure Analysis, Protons, Reproducibility of Results, Sensitivity and Specificity, Algorithms, Film Dosimetry instrumentation, Film Dosimetry methods, Models, Statistical, Radiotherapy, High-Energy instrumentation, Radiotherapy, High-Energy methods
- Abstract
Radiographic film dosimetry suffers from its energy dependence in proton dosimetry. This study sought to develop a method of measuring proton beams by the film and to evaluate film response to proton beams for the constancy check of depth dose (DD). It also evaluated the film for profile measurements. To achieve this goal, from DDs measured by film and ion chamber (IC), calibration factors (ratios of dose measured by IC to film responses) as a function of depth in a phantom were obtained. These factors imply variable slopes (with proton energy and depth) of linear characteristic curves that relate film response to dose. We derived a calibration method that enables utilization of the factors for acquisition of dose from film density measured at later dates by adapting to a potentially altered processor condition. To test this model, the characteristic curve was obtained by using EDR2 film and in-phantom film dosimetry in parallel with a 149.65 MeV proton beam, using the method. An additional validation of the model was performed by concurrent film and IC measurement perpendicular to the beam at various depths. Beam profile measurements by the film were also evaluated at the center of beam modulation. In order to interpret and ascertain the film dosimetry, Monte Carlos simulation of the beam was performed, calculating the proton fluence spectrum along depths and off-axis distances. By multiplying respective stopping powers to the spectrum, doses to film and water were calculated. The ratio of film dose to water dose was evaluated. Results are as follows. The characteristic curve proved the assumed linearity. The measured DD approached that of IC, but near the end of the spread-out Bragg peak (SOBP), a spurious peak was observed due to the mismatch of distal edge between the calibration and measurement films. The width of SOBP and the proximal edge were both reproducible within a maximum of 5mm; the distal edge was reproducible within 1 mm. At 5 cm depth, the dose was reproducible within 10%. These large discrepancies were identified to have been contributed by film processor uncertainty across a layer of film and the misalignment of film edge to the frontal phantom surface. The deviations could drop from 5 to 2 mm in SOBP and from 10% to 4.5% at 5 cm depth in a well-controlled processor condition(i.e., warm up). In addition to the validation of the calibration method done by the DD measurements, the concurrent film and IC measurement independently validated the model by showing the constancy of depth-dependent calibration factors. For profile measurement, the film showed good agreement with ion chamber measurement. In agreement with the experimental findings, computationally obtained ratio of film dose to water dose assisted understanding of the trend of the film response by revealing relatively large and small variances of the response for DD and beam profile measurements, respectively. Conclusions are as follows. For proton beams, radiographic film proved to offer accurate beam profile measurements. The adaptive calibration method proposed in this study was validated. Using the method, film dosimetry could offer reasonably accurate DD constancy checks, when provided with a well-controlled processor condition. Although the processor warming up can promote a uniform processing across a single layer of the film, the processing remains as a challenge.
- Published
- 2015
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44. Effect of Ginger Extract and Citric Acid on the Tenderness of Duck Breast Muscles.
- Author
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He FY, Kim HW, Hwang KE, Song DH, Kim YJ, Ham YK, Kim SY, Yeo IJ, Jung TJ, and Kim CJ
- Abstract
The objective of this study was to examine the effect of ginger extract (GE) combined with citric acid on the tenderness of duck breast muscles. Total six marinades were prepared with the combination of citric acid (0 and 0.3 M citric acid) and GE (0, 15, and 30%). Each marinade was sprayed on the surface of duck breasts (15 mL/100 g), and the samples were marinated for 72 h at 4℃. The pH and proteolytic activity of marinades were determined. After 72 h of marination, Warner Bratzler shear force (WBSF), myofibrillar fragmentation index (MFI), pH, cooking loss, moisture content, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and protein solubility were evaluated. There was no significant (p>0.05) difference in moisture content or cooking loss among all samples. However, GE marination resulted in a significant (p<0.05) decrease in WBSF but a significant (p<0.05) increase in pH and MFI. In addition, total protein and myofibrillar protein solubility of GE-marinated duck breast muscles in both WOC (without citric acid) and WC (with citric acid) conditions were significantly (p<0.05) increased compared to non-GE-marinated duck breast muscles. SDS-PAGE showed an increase of protein degradation (MHC and actin) in WC condition compared to WOC condition. There was a marked actin reduction in GE-treated samples in WC. The tenderization effect of GE combined with citric acid may be attributed to various mechanisms such as increased MFI and myofibrillar protein solubility.
- Published
- 2015
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45. Effects of Red and Green Glassworts (Salicornia herbacea L.) on Physicochemical and Textural Properties of Reduced-salt Cooked Sausages.
- Author
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Kim HW, Hwang KE, Song DH, Kim YJ, Ham YK, Yeo IJ, Jeong TJ, Choi YS, and Kim CJ
- Abstract
This study was conducted to determine the effects of red and green glasswort on the physicochemical and textural properties of reduced-salt cooked sausages. The control was formulated with 1.5% NaCl; then, three reduced-salt treatments were prepared, with 0.75% NaCl (RS), 0.75% NaCl+1.0% red glasswort (RSR) and 0.75% NaCl+1.0% green glasswort (RSG), respectively. The addition of glasswort within the added amount of 1% had no influence on the pH value of the reduced-salt cooked sausages, regardless of the glasswort type. In terms of color, RSG treatment conveyed a higher hue angle value than the RSR treatment (p<0.05). Increases in the protein solubility (total and myofibrillar proteins) and apparent viscosity of reduced-salt meat batter that were due to the addition of glasswort were observed; however, there were no differences according to the type of glasswort (p>0.05). Furthermore, the addition of glasswort, regardless of its type, resulted in decreased cooking loss, and increased emulsion stability. As a result, reduced-salt cooked sausages formulated with either red or green glasswort demonstrated similar textural properties to those of the control. In conclusion, the type of glasswort within an added amount of 1% had no influence on the physicochemical and textural properties of reduced-salt cooked sausages, except for the color characteristics. In terms of color alteration by the addition of glasswort, the red glasswort, which in comparison with the green glasswort could minimize the color changes of reduced-salt cooked sausages, might be an effective source for manufacturing meat products.
- Published
- 2014
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46. Conditions for reliable time-resolved dosimetry of electronic portal imaging devices for fixed-gantry IMRT and VMAT.
- Author
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Yeo IJ, Jung JW, Patyal B, Mandapaka A, Yi BY, and Kim JO
- Subjects
- Radiometry, Time Factors, Electrical Equipment and Supplies, Radiotherapy, Image-Guided instrumentation, Radiotherapy, Intensity-Modulated instrumentation
- Abstract
Purpose: The continuous scanning mode of electronic portal imaging devices (EPID) that offers time-resolved information has been newly explored for verifying dynamic radiation deliveries. This study seeks to determine operating conditions (dose rate stability and time resolution) under which that mode can be used accurately for the time-resolved dosimetry of intensity-modulated radiation therapy (IMRT) beams., Methods: The authors have designed the following test beams with variable beam holdoffs and dose rate regulations: a 10 × 10 cm open beam to serve as a reference beam; a sliding window (SW) beam utilizing the motion of a pair of multileaf collimator (MLC) leaves outside the 10 × 10 cm jaw; a step and shoot (SS) beam to move the pair in step; a volumetric modulated arc therapy (VMAT) beam. The beams were designed in such a way that they all produce the same open beam output of 10 × 10 cm. Time-resolved ion chamber measurements at isocenter and time-resolved and integrating EPID measurements were performed for all beams. The time-resolved EPID measurements were evaluated through comparison with the ion chamber and integrating EPID measurements, as the latter are accepted procedures. For two-dimensional, time-resolved evaluation, a VMAT beam with an infield MLC travel was designed. Time-resolved EPID measurements and Monte Carlo calculations of such EPID dose images for this beam were performed and intercompared., Results: For IMRT beams (SW and SS), the authors found disagreement greater than 2%, caused by frame missing of the time-resolved mode. However, frame missing disappeared, yielding agreement better than 2%, when the dose rate of irradiation (and thus the frame acquisition rates) reached a stable and planned rate as the dose of irradiation was raised past certain thresholds (a minimum 12 s of irradiation per shoot used for SS IMRT). For VMAT, the authors found that dose rate does not affect the frame acquisition rate, thereby causing no frame missing. However, serious inplanar nonuniformities were found. This could be overcome by sacrificing temporal resolution (10 frames or 0.95 s/image): the continuous images agreed with ion chamber responses at the center of EPID and the calculation two-dimensionally in a time-resolved manner., Conclusions: The authors have determined conditions under which the continuous mode can be used for time-resolved dosimetry of fixed-gantry IMRT and VMAT and demonstrated it for VMAT.
- Published
- 2013
- Full Text
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47. Feasibility study on inverse four-dimensional dose reconstruction using the continuous dose-image of EPID.
- Author
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Yeo IJ, Jung JW, Yi BY, and Kim JO
- Subjects
- Cone-Beam Computed Tomography, Feasibility Studies, Humans, Phantoms, Imaging, Radiotherapy Dosage, Reproducibility of Results, Electrical Equipment and Supplies, Four-Dimensional Computed Tomography instrumentation, Radiation Dosage, Radiotherapy, Image-Guided instrumentation
- Abstract
Purpose: When an intensity-modulated radiation beam is delivered to a moving target, the interplay effect between dynamic beam delivery and the target motion due to miss-synchronization can cause unpredictable dose delivery. The portal dose image in electronic portal imaging device (EPID) represents radiation attenuated and scattered through target media. Thus, it may possess information about delivered radiation to the target. Using a continuous scan (cine) mode of EPID, which provides temporal dose images related to target and beam movements, the authors' goal is to perform four-dimensional (4D) dose reconstruction., Methods: To evaluate this hypothesis, first, the authors have derived and subsequently validated a fast method of dose reconstruction based on virtual beamlet calculations of dose responses using a test intensity-modulated beam. This method was necessary for processing a large number of EPID images pertinent for four-dimensional reconstruction. Second, cine mode acquisition after summation over all images was validated through comparison with integration mode acquisition on EPID (IAS3 and aS1000) for the test beam. This was to confirm the agreement of the cine mode with the integrated mode, specifically for the test beam, which is an accepted mode of image acquisition for dosimetry with EPID. Third, in-phantom film and exit EPID dosimetry was performed on a moving platform using the same beam. Heterogeneous as well as homogeneous phantoms were used. The cine images were temporally sorted at 10% interval. The authors have performed dose reconstruction to the in-phantom plane from the sorted cine images using the above validated method of dose reconstruction. The reconstructed dose from each cine image was summed to compose a total reconstructed dose from the test beam delivery, and was compared with film measurements., Results: The new method of dose reconstruction was validated showing greater than 95.3% pass rates of the gamma test with the criteria of dose difference of 3% and distance to agreement of 3 mm. The dose comparison of the reconstructed dose with the measured dose for the two phantoms showed pass rates higher than 96.4% given the same criteria., Conclusions: Feasibility of 4D dose reconstruction was successfully demonstrated in this study. The 4D dose reconstruction demonstrated in this study can be a promising dose validation method for radiation delivery on moving organs.
- Published
- 2013
- Full Text
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48. Fast transit portal dosimetry using density-scaled layer modeling of aSi-based electronic portal imaging device and Monte Carlo method.
- Author
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Jung JW, Kim JO, Yeo IJ, Cho YB, Kim SM, and DiBiase S
- Subjects
- Computer Simulation, Equipment Design, Equipment Failure Analysis, Radiotherapy Dosage, Models, Statistical, Monte Carlo Method, Radiometry instrumentation, Radiometry methods, Radiotherapy, Conformal instrumentation, Radiotherapy, Conformal methods, X-Ray Intensifying Screens
- Abstract
Purpose: Fast and accurate transit portal dosimetry was investigated by developing a density-scaled layer model of electronic portal imaging device (EPID) and applying it to a clinical environment., Methods: The model was developed for fast Monte Carlo dose calculation. The model was validated through comparison with measurements of dose on EPID using first open beams of varying field sizes under a 20-cm-thick flat phantom. After this basic validation, the model was further tested by applying it to transit dosimetry and dose reconstruction that employed our predetermined dose-response-based algorithm developed earlier. The application employed clinical intensity-modulated beams irradiated on a Rando phantom. The clinical beams were obtained through planning on pelvic regions of the Rando phantom simulating prostate and large pelvis intensity modulated radiation therapy. To enhance agreement between calculations and measurements of dose near penumbral regions, convolution conversion of acquired EPID images was alternatively used. In addition, thickness-dependent image-to-dose calibration factors were generated through measurements of image and calculations of dose in EPID through flat phantoms of various thicknesses. The factors were used to convert acquired images in EPID into dose., Results: For open beam measurements, the model showed agreement with measurements in dose difference better than 2% across open fields. For tests with a Rando phantom, the transit dosimetry measurements were compared with forwardly calculated doses in EPID showing gamma pass rates between 90.8% and 98.8% given 4.5 mm distance-to-agreement (DTA) and 3% dose difference (DD) for all individual beams tried in this study. The reconstructed dose in the phantom was compared with forwardly calculated doses showing pass rates between 93.3% and 100% in isocentric perpendicular planes to the beam direction given 3 mm DTA and 3% DD for all beams. On isocentric axial planes, the pass rates varied between 95.8% and 99.9% for all individual beams and they were 98.2% and 99.9% for the composite beams of the small and large pelvis cases, respectively. Three-dimensional gamma pass rates were 99.0% and 96.4% for the small and large pelvis cases, respectively., Conclusions: The layer model of EPID built for Monte Carlo calculations offered fast (less than 1 min) and accurate calculation for transit dosimety and dose reconstruction.
- Published
- 2012
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49. Study of double bond equivalents and the numbers of carbon and oxygen atom distribution of dissolved organic matter with negative-mode FT-ICR MS.
- Author
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Bae E, Yeo IJ, Jeong B, Shin Y, Shin KH, and Kim S
- Subjects
- Fourier Analysis, Fresh Water chemistry, Seawater chemistry, Carbon chemistry, Mass Spectrometry methods, Organic Chemicals chemistry, Oxygen chemistry
- Abstract
A strong linear relationship was observed between the average double bond equivalence (DBE) and the ratio of carbon to oxygen atoms in oxygenated compounds of dissolved organic matter (DOM). Data were acquired by a Fourier transform ion cyclotron resonance mass spectrometer (FT-ICR MS), equipped with a negative-mode electrospray ionization source. The slope and y-intercepts extracted from the linear relationship can be used to compare DOM samples originating from different locations. Significant differences in these parameters were observed between inland riverine and offshore coastal DOM samples. Offshore coastal DOM molecules underwent a change of one DBE for each removal or addition of two oxygen atoms. This suggested the existence of multiple carboxyl groups, each of which contains a double bond and two oxygen atoms. Inland riverine samples exhibited a change of ~1.5 DBE following the addition or removal of two oxygen atoms. This extra change in DBE was attributed to cyclic structures or unsaturated chemical bonds. The DBE value with maximum relative abundance and the minimum DBE value for each class of oxygenated compounds showed that approximately two oxygen atoms contributed to a unity change in DBE. The qualitative analyses given here are in a good agreement with results obtained from analyses using orthogonal analytical techniques. This study demonstrates that DBE and the carbon number distribution, observed by high resolution mass spectrometry, can be valuable in elucidating and comparing structural features of oxygenated molecules of DOM.
- Published
- 2011
- Full Text
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50. Dose reconstruction for intensity-modulated radiation therapy using a non-iterative method and portal dose image.
- Author
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Yeo IJ, Jung JW, Chew M, Kim JO, Wang B, Dibiase S, Zhu Y, and Lee D
- Subjects
- Algorithms, Humans, Monte Carlo Method, Phantoms, Imaging, Radiotherapy Dosage, Radiotherapy, Intensity-Modulated instrumentation, Reproducibility of Results, Radiation Dosage, Radiotherapy, Intensity-Modulated methods
- Abstract
A straightforward and accurate method was developed to verify the delivery of intensity-modulated radiation therapy (IMRT) and to reconstruct the dose in a patient. The method is based on a computational algorithm that linearly describes the physical relationship between beamlets and dose-scoring voxels in a patient and the dose image from an electronic portal imaging device (EPID). The relationship is expressed in the form of dose response functions (responses) that are quantified using Monte Carlo (MC) particle transport techniques. From the dose information measured by the EPID the received patient dose is reconstructed by inversely solving the algorithm. The unique and novel non-iterative feature of this algorithm sets it apart from many existing dose reconstruction methods in the literature. This study presents the algorithm in detail and validates it experimentally for open and IMRT fields. Responses were first calculated for each beamlet of the selected fields by MC simulation. In-phantom and exit film dosimetry were performed on a flat phantom. Using the calculated responses and the algorithm, the exit film dose was used to inversely reconstruct the in-phantom dose, which was then compared with the measured in-phantom dose. The dose comparison in the phantom for all irradiated fields showed a pass rate of higher than 90% dose points given the criteria of dose difference of 3% and distance to agreement of 3 mm.
- Published
- 2009
- Full Text
- View/download PDF
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