• Title, Summary, Keyword: ROS

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Effect of Sargassum micracanthum extract on Lipid Accumulation and Reactive Oxygen Species (ROS) Production during Differentiation of 3T3-L1 Preadipocytes (3T3-L1 세포분화 중 지방축적 및 ROS 생성에 대한 잔가시 모자반 추출물의 효과)

  • Lee, Young-Jun;Yoon, Bo-Ra;Choi, Hyeon-Son;Lee, Boo-Yong;Lee, Ok-Hwan
    • Korean Journal of Food Preservation
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    • v.19 no.3
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    • pp.455-461
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    • 2012
  • Obesity, a strong risk factor for the development of chronic diseases, is characterized by an increase in the number and size of adipocytes differentiated from precursor cells, preadipocytes. Recent research suggests that increased reactive oxygen species (ROS) production in 3T3-L1 adipocyte facilitates adipocyte differentiation and fat accumulation. This study was to investigate whether reduced ROS production by Sargassum micracanthum extract (SME) could protect the development of obesity through inhibition of adipogenesis. 3T3-L1 preadipocytes were treated SME for up to 8 days following standard induction of differentiation. The extent of differentiation reflected by amount of lipid accumulation and ROS production was determined by Oil red O staining and nitroblue tetrazolium (NBT) assay. Treatment of SME significantly inhibited ROS production and adipocyte differentiation that is depend on down regulation of NADPH oxidase 4 (NOX4), a major ROS generator, and peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) and CCAAT/enhancer-binding protein alpha ($C/EBP{\alpha}$), a key adipogenic transcription factor. These results indicate that SME can inhibit adipogenesis through a reduced ROS level that involves down-regulation of NOX4 expression or via modulation of adipogenic transcription factor.

Role of Nox4 in Neuronal Differentiation of Mouse Subventricular Zone Neural Stem Cells (쥐의 뇌실 하 영역(SVZ) 신경 줄기 세포의 신경 세포로의 분화 과정에서 Nox4의 역할)

  • Park, Ki-Youb;Na, Yerin;Kim, Man Su
    • Journal of Life Science
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    • v.26 no.1
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    • pp.8-16
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    • 2016
  • Reactive oxygen species (ROS), at appropriate concentrations, mediate various normal cellular functions, including defense against pathogens, signal transduction, cellular growth, and gene expression. A recent study demonstrated that ROS and ROS-generating NADPH oxidase (Nox) are important in self-renewal and neuronal differentiation of subventricular zone (SVZ) neural stem cells in adult mouse brains. In this study, we found that endogenous ROS were detected in SVZ neural stem cells cultured from postnatal mouse brains. Nox4 was predominantly expressed in cultured cells, while the levels of the Nox1 and Nox2 transcripts were very low. In addition, the Nox4 gene was highly upregulated (by up to 10-fold) during neuronal differentiation. Immunocytochemical analysis detected the Nox4 protein mainly in neurons positive for the neuronal specific tubulin Tuj1. After differentiation, endogenous ROS were detected exclusively in neuron-like cells with processes. In addition, perturbation of the cellular redox state with N-acetyl cysteine, a ROS scavenger, during neuronal differentiation greatly inhibited neurogenesis. Lastly, knockdown of Nox4 using short hairpin RNA decreased neurogenesis. These findings suggest that Nox4 may be a major ROS-generating enzyme in postnatal SVZ neural stem cells, and Nox4-mediated ROS generation may be important in their neuronal differentiation.

How to fix errors in ROS installation and control for TurtleBot 3 (터틀봇3를 위한 ROS 설치 및 제어의 오류 해결 방법)

  • Park, Tae-Whan;Lee, Kang-Hee
    • Proceedings of the Korean Society of Computer Information Conference
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    • pp.331-334
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    • 2020
  • 터틀봇3(Turtlebot3)을 제어하기 위하여 피시와 터틀봇3 각각에 ROS(Robot Operating System)을 설치하고 제어한다. 터틀봇3는 라즈베리파이 3 보드로 제어되는 오픈소스 로봇이다. 전세계에서 유명한 교육 및 연구용 로봇이지만 설치와 제어 과정에서 여러 오류를 경험하는 사용자들이 있다. 본 논문은 터틀봇3를 처음 사용하는 사용자들을 위하여 설치과정과 설치과정에서 발생하는 오류들에 대하여 다룬다.

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Inhibitory Effects of Allium senescens L. Methanol Extracts on Reactive Oxygen Species Production and Lipid Accumulation during Differentiation in 3T3-L1 Cells (두메부추(Allium senescens L.) 메탄올 추출물의 지방세포 내 활성산소종 생성 및 지질축적 억제 효능)

  • Choi, Hye-Young;Kim, Gun-Hee
    • Korean Journal of Food Science and Technology
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    • v.46 no.4
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    • pp.498-504
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    • 2014
  • Allium senescens L. is perennial plant of the Liliaceae family that grows throughout Korea. In this study, we investigated the effect of Allium senescens L. methanol extracts on reactive oxygen species (ROS) production and lipid accumulation during adipogenesis. Our results indicated that 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity of Allium senescens L. methanol extracts increased in a dose-dependent manner. Allium senescens L. methanol extracts suppressed ROS production and lipid accumulation during adipogenesis. In addition, Allium senescens L. methanol extracts inhibited the mRNA expression of the pro-oxidant enzyme, such as G6PDH and lead to a reduction in the mRNA levels of the transcription factors, such as sterol regulatory element binding proteins 1c, peroxisome proliferator-activated receptor ${\gamma}$, and CCAAT/enhancer-binding proteins ${\alpha}$. These results indicate that Allium senescens L. methanol extracts inhibit adipogenesis by modulating ROS production associated with ROS-regulating genes and directly down-regulating adipogenic transcription factors.

Effects of NADPH Oxidase Inhibitors and Mitochondria-Targeted Antioxidants on Amyloid β1-42-Induced Neuronal Deaths in Mouse Mixed Cortical Cultures

  • Hwang, Shinae;Kim, Jong-Keun
    • Chonnam Medical Journal
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    • v.54 no.3
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    • pp.159-166
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    • 2018
  • The Amyloid ${\beta}$ peptide ($A{\beta}$) is a main component of senile plaques in Alzheimer's disease. Currently, NADPH oxidase (NOX) and mitochondria are considered as primary sources of ROS induced by $A{\beta}$. However, the contribution of NOX and mitochondria to $A{\beta}$-induced ROS generation has not been well defined. To delineate the relative involvement of NOX and mitochondria in $A{\beta}$-induced ROS generation and neuronal death in mouse cortical cultures, we examined the effect of NOX inhibitors, apocynin and AEBSF, and the mitochondria-targeted antioxidants (MTAs), mitotempol and mitoquinone, on $A{\beta}$-induced ROS generation and neuronal deaths. Cell death was assessed by measuring lactate dehydrogenase efflux in bathing media at 24 and 48 hrs after exposure to $A{\beta}_{1-42}$. $A{\beta}_{1-42}$ induced dose- and time-dependent neuronal deaths in cortical cultures. Treatment with $20{\mu}M\;A{\beta}_{1-42}$ markedly and continuously increased not only the DHE fluorescence (intracellular ROS signal), but also the DHR123 fluorescence (mitochondrial ROS signal) up to 8 hrs. Treatment with apocynin or AEBSF selectively suppressed the increase in DHE fluorescence, while treatment with mitotempol selectively suppressed the increase in DHR123 fluorescence. Each treatment with apocynin, AEBSF, mitotempol or mitoquinone significantly attenuated the $A{\beta}_{1-42}$-induced neuronal deaths. However, any combined treatment with apocynin/AEBSF and mitotempol/mitoquinone failed to show additive effects. These findings indicate that $20{\mu}M$ $A{\beta}_{1-42}$ induces oxidative neuronal death via inducing mitochondrial ROS as well as NOX activation in mixed cortical cultures, but combined suppression of intracellular and mitochondrial ROS generation fail to show any additive neuroprotective effects against $A{\beta}$ neurotoxicity.

Effect of Atrial Natriuretic Peptide on the Proliferation and Activity of Osteoblastic Cells

  • Lee, Jong-Ryeul;Ko, Seon-Yle;Kim, Jung-Keun;Kim, Se-Won
    • The Korean Journal of Physiology and Pharmacology
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    • v.4 no.4
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    • pp.283-289
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    • 2000
  • Natriuretic peptides comprise a family of three structurally related peptides; atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and C-type natriuretic peptide (CNP). The present study was performed to investigate the effect of ANP on the proliferation and activity of ROS17/2.8 and HOS cells which are well-characterized osteoblastic cell lines. ANP dose-dependently decreased the number of ROS17/2.8 and HOS cells after 48-hour treatment. ANP generally increased the alkaline phosphatase activity of ROS17/2.8 and HOS cells after 48 hr treatment, regardless of the fact that basal activity of alkaline phosphatase was much lower in HOS cells compared to that of ROS17/1.8 cells. ANP increased the NBT reduction by ROS17/2.8 and HOS cells. ANP showed the variable but no significant effect on the nitric oxide production by ROS17/2.8 and HOS cells. ROS17/2.8 and HOS cells produced and secreted gelatinase into culture medium, and this enzyme was thought to be the gelatinase A type with the molecular weight determination. The gelatinase activity produced by ROS17/2.8 cells was increased by the treatment of ANP. However, the enzyme activity was not affected by ANP treatment in the HOS cell culture. In summary, ANP decreased the proliferation and increased the alkaline phosphatase activity and NBT reduction of osteoblasts. These results indicate that ANP is one of the important regulators of bone metabolism.

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A Relay System for Supporting the Execution of Context-Aware Robot Services on ROS (ROS를 이용하여 상황인지 기반의 로봇 서비스를 실행시키기 위한 중계 시스템)

  • Lee, Minho;Choi, Jongsun;Choi, Jaeyoung
    • KIPS Transactions on Computer and Communication Systems
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    • v.6 no.5
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    • pp.211-218
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    • 2017
  • Recent robot software platform research focuses on providing intelligent service via abstraction of robot devices. Context-aware techniques are necessary for intelligent robot services, which are based on the perception of environmental information obtained from heterogeneous sensors in IoT environment. Robot Operating System (ROS) provides protocols to operate robot devices. ROS includes functions for abstracting heterogeneous sensors themselves in order to control the robot, however, it lacks the ability to provide context information that the robot can perceive based on environmental information through consistent collection methods. In this paper, we propose a relay system for ROS to provide context-aware robot service. The proposed system makes it possible for ROS to control and provide context-aware robot services with relay of an external context-aware system and ROS. In experiments, we demonstrate procedures that robot services abstracted from ROS and an external context-aware system works together based on the proposed system.

A Pattern Recognition Receptor, SIGN-R1, Mediates ROS Generation against Polysaccharide Dextran, Resulting in Increase of Peroxiredoxin-1 and Its Interaction to SIGN-R1

  • Choi, Heong-Jwa;Choi, Woo-Sung;Park, Jin-Yeon;Kang, Kyeong-Hyeon;Prabagar, Miglena G.;Shin, Chan-Young;Kang, Young-Sun
    • Biomolecules & Therapeutics
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    • v.18 no.3
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    • pp.271-279
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    • 2010
  • Streptococcus pneumoniae is the major pathogen that frequently causes serious infections in children, the elderly and immunocompromised patients. S. pneumoniae is known to produce reactive oxygen species (ROS) and S. pneumoniae-produced ROS is considered to play a role in pneumococci pathogenesis. SIGN-R1 is the principal receptor of capsular polysaccharides (CPSs) of S. pneumoniae. However, there is a considerable lack of knowledge about the protective role of SIGN-R1 against S. pneumoniae-produced ROS in SIGN-$R1^+$ macrophages. While investigating the protective role of SIGN-R1 against ROS, we found that SIGN-R1 intimately bound to peroxiredoxin-1 (Prx-1), one of small antioxidant proteins in vitro and in vivo. This interaction was increased with ROS generation which was produced by stimulating SIGN-R1 with dextran, a polysaccharide ligand of SIGN-R1. Also, SIGN-R1 crosslinking with 22D1 anti-SIGN-R1 antibody increased Prx-1 in vitro or in vivo. These results suggested that SIGN-R1 stimulation with CPSs of S. pneumoniae increase the expression level of Prx-1 through ROS and its subsequent interaction to SIGN-R1, providing an important antioxidant role for the host protection against S. pneumoniae.

Streptochlorin Isolated from Streptomyces sp. Induces Apoptosis in Human Hepatocarcinoma Cells Through a Reactive Oxygen Species-Mediated Mitochondrial Pathway

  • Shin, Dong-Yeok;Shin, Hee-Jae;Kim, Gi-Young;Cheong, Jae-Hun;Choi, Il-Whan;Kim, Se-Kwon;Moon, Sung-Kwon;Kang, Ho-Sung;Choi, Yung-Hyun
    • Journal of Microbiology and Biotechnology
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    • v.18 no.11
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    • pp.1862-1867
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    • 2008
  • Streptochlorin is a small molecule isolated from marine Streptomyces sp. that is known to have antiangiogenic and anticancer properties. In this study, we examined the effects of this compound on reactive oxygen species (ROS) production and the association of these effects with apoptotic tumor cell death, using a human hepatocarcinoma Hep3B cell line. The results of this study demonstrated that streptochlorin mediates ROS production, and that this mediation is followed by a decrease in the mitochondrial membrane potential (MMP, ${\Delta}{\Psi}_m$), activation of caspase-3, and downregulation of antiapoptotic Bcl-2 protein. The quenching of ROS generation by N-acetyl-L-cysteine administration, a scavenger of ROS, reversed the streptochlorin-induced apoptosis effects via inhibition of ROS production, MMP collapse, and the subsequent activation of caspase-3. These observations clearly indicate that ROS are involved in the early molecular events in the streptochlorin-induced apoptotic pathway. Taken together, our data imply that streptochlorin-induced ROS is a key mediator of MMP collapse, which leads to the caspase-3 activation, culminating in apoptosis.

Saussurea Lappa Radix-induced cytotoxicity via ROS generation in A549 lung cancer cells (A549세포에 대한 목향추출물의 ROS 매개 세포독성)

  • Lee, Young-Joon;Ku, Sae-Kwang;Kang, Su-Jin
    • Journal of Society of Preventive Korean Medicine
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    • v.17 no.2
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    • pp.169-178
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    • 2013
  • Objectives : Many cancers acquired resistance to chemotherapy, thus limiting its anticancer efficacy. It is known that Glutathione (GSH) is related to the development of drug resistance. The expression of GSH synthesizing glutamylcysteine ligase (GCL) was controlled by nuclear factor-E2-related factor(Nrf2). Previous studies showed that pharmacological depletion of GSH results in ROS increase, apoptotic response, and sensitization to oxidizing stimuli. In the current study, we examined Saussurea Lappa (SL) have the inhibitory effect on Nrf2 activity using human lung cancer A549 cells overexpressing Nrf2. Methods : Cell viability of A549 cells on SL treatment was determined by MTT assay. To detect the apeptosis in SL-treated A549 cells, sub-G1 population was measured by flow cytometry analysis (FACS). The level ROS was determined by FACS and fluorescence microscopy. To investigate whether SL have effect the suppression on Nrf2, we performed western blotting analysis. The GSH content was measured since GSH plays an important role in response to oxidative stress and was regulated by Nrf2. Results : A549 cells treated with an SL extract showed a substantial decrease in cell viability, along with a concomitant increase in apoptosis compared to untreated cells. Treatment of the SL extract led to increased Reactive oxygen species (ROS) production and a suppression of Nrf2. In addition, the antioxidant NAC attenuated SL-induced ROS generation, Nrf2 inhibition, and apoptosis. Taken together, these data show that the SL extract induced the production of ROS, and the inhibition of Nrf2, consequently resulting in A549 cell death. Conclusions : These results suggest that SL might be an effective agent to enhance anticancer drug sensitivity via Nrf2 inhibition.