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Chen F, Che Z, Liu Y, Luo P, Xiao L, Song Y, Wang C, Dong Z, Li M, Tipoe GL, Yang M, Lv Y, Zhang H, Wang F, Xiao J. Invigorating human MSCs for transplantation therapy via Nrf2/DKK1 co-stimulation in an acute-on-chronic liver failure mouse model. Gastroenterol Rep (Oxf) 2024; 12:goae016. [PMID: 38529014 PMCID: PMC10963075 DOI: 10.1093/gastro/goae016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 11/27/2023] [Accepted: 02/21/2024] [Indexed: 03/27/2024] Open
Abstract
Background Since boosting stem cell resilience in stressful environments is critical for the therapeutic efficacy of stem cell-based transplantations in liver disease, this study aimed to establish the efficacy of a transient plasmid-based preconditioning strategy for boosting the capability of mesenchymal stromal cells (MSCs) for anti-inflammation/antioxidant defenses and paracrine actions in recipient hepatocytes. Methods Human adipose mesenchymal stem cells (hADMSCs) were subjected to transfer, either with or without the nuclear factor erythroid 2-related factor 2 (Nrf2)/Dickkopf1 (DKK1) genes, followed by exposure to TNF-α/H2O2. Mouse models were subjected to acute chronic liver failure (ACLF) and subsequently injected with either transfected or untransfected MSCs. These hADMSCs and ACLF mouse models were used to investigate the interaction between Nrf2/DKK1 and the hepatocyte receptor cytoskeleton-associated protein 4 (CKAP4). Results Activation of Nrf2 and DKK1 enhanced the anti-stress capacity of MSCs in vitro. In a murine model of ACLF, transient co-overexpression of Nrf2 and DKK1 via plasmid transfection improved MSC resilience against inflammatory and oxidative assaults, boosted MSC transplantation efficacy, and promoted recipient liver regeneration due to a shift from the activation of the anti-regenerative IFN-γ/STAT1 pathway to the pro-regenerative IL-6/STAT3 pathway in the liver. Importantly, the therapeutic benefits of MSC transplantation were nullified when the receptor CKAP4, which interacts with DKK1, was specifically removed from recipient hepatocytes. However, the removal of the another receptor low-density lipoprotein receptor-related protein 6 (LRP6) had no impact on the effectiveness of MSC transplantation. Moreover, in long-term observations, no tumorigenicity was detected in mice following transplantation of transiently preconditioned MSCs. Conclusions Co-stimulation with Nrf2/DKK1 safely improved the efficacy of human MSC-based therapies in murine models of ACLF through CKAP4-dependent paracrine mechanisms.
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Affiliation(s)
- Feng Chen
- Division of Gastroenterology, Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen, Guangdong, P. R. China
- National Clinical Research Center for Infectious Diseases, Second Affiliated Hospital of Southern University of Science and Technology, Shenzhen, Guangdong, P. R. China
| | - Zhaodi Che
- Clinical Medicine Research Institute and Department of Metabolic and Bariatric Surgery, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong, P. R. China
| | - Yingxia Liu
- National Clinical Research Center for Infectious Diseases, Second Affiliated Hospital of Southern University of Science and Technology, Shenzhen, Guangdong, P. R. China
| | - Pingping Luo
- Clinical Medicine Research Institute and Department of Metabolic and Bariatric Surgery, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong, P. R. China
| | - Lu Xiao
- Clinical Medicine Research Institute and Department of Metabolic and Bariatric Surgery, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong, P. R. China
| | - Yali Song
- Clinical Medicine Research Institute and Department of Metabolic and Bariatric Surgery, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong, P. R. China
| | - Cunchuan Wang
- Clinical Medicine Research Institute and Department of Metabolic and Bariatric Surgery, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong, P. R. China
| | - Zhiyong Dong
- Clinical Medicine Research Institute and Department of Metabolic and Bariatric Surgery, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong, P. R. China
| | - Mianhuan Li
- National Clinical Research Center for Infectious Diseases, Second Affiliated Hospital of Southern University of Science and Technology, Shenzhen, Guangdong, P. R. China
| | - George L Tipoe
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong SAR, P. R. China
| | - Min Yang
- National Clinical Research Center for Infectious Diseases, Second Affiliated Hospital of Southern University of Science and Technology, Shenzhen, Guangdong, P. R. China
| | - Yi Lv
- Laboratory of Neuroendocrinology, Fujian Key Laboratory of Developmental and Neurobiology, School of Life Sciences, Fujian Normal University, Fuzhou, Fujian, P. R. China
| | - Hong Zhang
- Department of Surgery, The Sixth Affiliated Hospital of Jinan University, Jinan University, Dongguan, Guangdong, P. R. China
| | - Fei Wang
- Division of Gastroenterology, Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen, Guangdong, P. R. China
| | - Jia Xiao
- Clinical Medicine Research Institute and Department of Metabolic and Bariatric Surgery, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong, P. R. China
- Department of Surgery, The Sixth Affiliated Hospital of Jinan University, Jinan University, Dongguan, Guangdong, P. R. China
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Ishii T, Warabi E, Mann GE. Mechanisms underlying Nrf2 nuclear translocation by non-lethal levels of hydrogen peroxide: p38 MAPK-dependent neutral sphingomyelinase2 membrane trafficking and ceramide/PKCζ/CK2 signaling. Free Radic Biol Med 2022; 191:191-202. [PMID: 36064071 DOI: 10.1016/j.freeradbiomed.2022.08.036] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 08/22/2022] [Accepted: 08/29/2022] [Indexed: 12/14/2022]
Abstract
Hydrogen peroxide is an aerobic metabolite playing a central role in redox signaling and oxidative stress. H2O2 could activate redox sensitive transcription factors, such as Nrf2, AP-1 and NF-κB by different manners. In some cells, treatment with non-lethal levels of H2O2 induces rapid activation of Nrf2, which upregulates expression of a set of genes involved in glutathione (GSH) synthesis and defenses against oxidative damage. It depends on two steps, the rapid translational activation of Nrf2 and facilitation of Nrf2 nuclear translocation. We review the molecular mechanisms by which H2O2 induces nuclear translocation of Nrf2 in cultured cells by highlighting the role of neutral sphingomyelinase 2 (nSMase2), a GSH sensor. H2O2 enters cells through aquaporin channels in the plasma membrane and is rapidly reduced to H2O by GSH peroxidases to consume cellular GSH, resulting in nSMase2 activation to generate ceramide. H2O2 also activates p38 MAP kinase, which enhances transfer of nSMase2 from perinuclear regions to plasma membrane lipid rafts to accelerate ceramide generation. Low levels of ceramide activate PKCζ, which then activates casein kinase 2 (CK2). These protein kinases are able to phosphorylate Nrf2 to stabilize and activate it. Notably, Nrf2 also binds to caveolin-1 (Cav1), which protects Nrf2 from Keap1-mediated degradation and limits Nrf2 nuclear translocation. We propose that Cav1serves as a signaling hub for the control of H2O2-mediated phosphorylation of Nrf2 by kinases, which results in release of Nrf2 from Cav1 to facilitate nuclear translocation. In summary, H2O2 induces GSH depletion which is recovered by Nrf2 activation dependent on p38/nSMase2/ceramide signaling.
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Affiliation(s)
- Tetsuro Ishii
- School of Medicine, University of Tsukuba, Tsukuba, Ibaraki, 305-8577, Japan.
| | - Eiji Warabi
- School of Medicine, University of Tsukuba, Tsukuba, Ibaraki, 305-8577, Japan.
| | - Giovanni E Mann
- King's British Heart Foundation Centre of Research Excellence, School of Cardiovascular and Metabolic Medicine & Sciences, Faculty of Life Sciences & Medicine, King's College London, 150 Stamford Street, London, SE1 9NH, UK.
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Waczuk EP, Kamdem JP, Abolaji AO, Meinerz DF, Caeran Bueno D, do Nascimento Gonzaga TKS, do Canto Dorow TS, Boligon AA, Athayde ML, da Rocha JBT, Ávila DS. Euphorbia tirucalli aqueous extract induces cytotoxicity, genotoxicity and changes in antioxidant gene expression in human leukocytes. Toxicol Res (Camb) 2015. [DOI: 10.1039/c4tx00122b] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The medicinal use of Euphorbia tirucalli has to be made with caution, as our study indicates that the aqueous extract induces genotoxicity and cytotoxicity in human leukocytes
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Affiliation(s)
| | - Jean Paul Kamdem
- Departamento de Química
- Centro de Ciências Naturais e Exatas
- Universidade Federal de Santa Maria
- Santa Maria
- Brazil
| | - Amos Olalekan Abolaji
- Departamento de Química
- Centro de Ciências Naturais e Exatas
- Universidade Federal de Santa Maria
- Santa Maria
- Brazil
| | - Daiane Francine Meinerz
- Departamento de Química
- Centro de Ciências Naturais e Exatas
- Universidade Federal de Santa Maria
- Santa Maria
- Brazil
| | - Diones Caeran Bueno
- Departamento de Química
- Centro de Ciências Naturais e Exatas
- Universidade Federal de Santa Maria
- Santa Maria
- Brazil
| | | | | | - Aline Augusti Boligon
- Programa de Pós-Graduação em Ciências Farmacêuticas
- Universidade Federal de Santa Maria
- Santa Maria
- Brazil
| | - Margareth Linde Athayde
- Programa de Pós-Graduação em Ciências Farmacêuticas
- Universidade Federal de Santa Maria
- Santa Maria
- Brazil
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Chowdhury I, Mo Y, Gao L, Kazi A, Fisher AB, Feinstein SI. Oxidant stress stimulates expression of the human peroxiredoxin 6 gene by a transcriptional mechanism involving an antioxidant response element. Free Radic Biol Med 2009; 46:146-53. [PMID: 18973804 PMCID: PMC2646855 DOI: 10.1016/j.freeradbiomed.2008.09.027] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2008] [Revised: 08/22/2008] [Accepted: 09/19/2008] [Indexed: 02/07/2023]
Abstract
Peroxiredoxin 6 (Prdx6) is a unique antioxidant enzyme that can reduce phospholipid and other hydroperoxides. A549 cells, a human lung-derived cell line, express both Prdx6 and Nrf2, a transcription factor that binds to antioxidant-response elements (AREs) and promotes expression of antioxidant genes. Treatment of A549 cells with 500 microM H(2)O(2) increased Prdx6 mRNA levels 2.5-fold, whereas treatment with 400 microM H(2)O(2) or 200 microM tert-butylhydroquinone (t-BHQ) triggered a corresponding 2.5-fold increase in reporter gene activity in A549 cells transfected with the pSEAP2:Basic vector (BD Bioscience), containing 1524 nucleotides of the human Prdx6 promoter region. Deletion of a consensus ARE sequence present between positions 357 and 349 before the start of transcription led to a striking decrease in both basal and H(2)O(2)- or t-BHQ-induced activation in A549 cells and H(2)O(2)-induced activation in primary rat alveolar type II cells. Cotransfection with Nrf2 stimulated the Prdx6 promoter in an ARE-dependent manner, whereas it was negatively regulated by Nrf3. siRNA targeting Nrf2 down-regulated reporter gene expression, whereas siRNA targeting the Nrf2 repressor, Keap1, up-regulated it. Binding of Nrf2 to the ARE sequence in chromatin was confirmed by PCR after chromatin immunoprecipitation. These data demonstrate that the ARE within the Prdx6 promoter is a key regulator of basal transcription of the Prdx6 gene and of its inducibility under conditions of oxidative stress.
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Affiliation(s)
- Ibrul Chowdhury
- Institute for Environmental Medicine, University of Pennsylvania School of Medicine, 1 John Morgan Building, 3620 Hamilton Walk, Philadelphia, PA 19104-6068, USA
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Williams MA, Rangasamy T, Bauer SM, Killedar S, Karp M, Kensler TW, Yamamoto M, Breysse P, Biswal S, Georas SN. Disruption of the transcription factor Nrf2 promotes pro-oxidative dendritic cells that stimulate Th2-like immunoresponsiveness upon activation by ambient particulate matter. THE JOURNAL OF IMMUNOLOGY 2008; 181:4545-59. [PMID: 18802057 DOI: 10.4049/jimmunol.181.7.4545] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Oxidative stress is important in dendritic cell (DC) activation. Environmental particulate matter (PM) directs pro-oxidant activities that may alter DC function. Nuclear erythroid 2 p45-related factor 2 (Nrf2) is a redox-sensitive transcription factor that regulates expression of antioxidant and detoxification genes. Oxidative stress and defective antioxidant responses may contribute to the exacerbations of asthma. We hypothesized that PM would impart differential responses by Nrf2 wild-type DCs as compared with Nrf2(-/-) DCs. We found that the deletion of Nrf2 affected important constitutive functions of both bone marrow-derived and highly purified myeloid lung DCs such as the secretion of inflammatory cytokines and their ability to take up exogenous Ag. Stimulation of Nrf2(-/-) DCs with PM augmented oxidative stress and cytokine production as compared with resting or Nrf2(+/+) DCs. This was associated with the enhanced induction of Nrf2-regulated antioxidant genes. In contrast to Nrf2(+/+) DCs, coincubation of Nrf2(-/-) DCs with PM and the antioxidant N-acetyl cysteine attenuated PM-induced up-regulation of CD80 and CD86. Our studies indicate a previously underappreciated role of Nrf2 in innate immunity and suggest that deficiency in Nrf2-dependent pathways may be involved in susceptibility to the adverse health effects of air pollution in part by promoting Th2 cytokine responses in the absence of functional Nrf2. Moreover, our studies have uncovered a hierarchal response to oxidative stress in terms of costimulatory molecule expression and cytokine secretion in DCs and suggest an important role of heightened oxidative stress in proallergic Th2-mediated immune responses orchestrated by DCs.
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Affiliation(s)
- Marc A Williams
- Division of Pulmonary and Critical Care Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA.
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Tsao TP, Lai JH, Yang SP, Ho LJ, Liou JT, Cheng CC, Cheng SM. Suppression of tissue necrosis factor-alpha or hydrogen peroxide-activated primary human T lymphocytes by Ginkgo biloba extract through down-regulation of activator protein-1 signal transduction. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2008; 15:170-6. [PMID: 17481873 DOI: 10.1016/j.phymed.2007.03.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2006] [Accepted: 02/28/2007] [Indexed: 05/15/2023]
Abstract
PURPOSE It was unknown whether Ginkgo biloba extract has regulatory effects on human T lymphocytes activated by tissue necrosis factor-alpha (TNF-alpha), which has an important role on the progression of inflammatory atherosclerotic plaques. We evaluated the effects of G. biloba extract on activated human peripheral T lymphocytes, which were isolated from human whole blood. METHODS The human T lymphocytes were treated with 25-100 microg G. biloba extract for 2h first. Then they were activated by TNF-alpha and H(2)O(2) to investigate the modulatory effects of G. biloba extract on human T lymphocytes. Electrophoretic mobility shift assay, Western blot (Immunoblot) analysis and immunoprecipitation kinase assays were used. RESULTS The inhibition of activated human T lymphocyte specifically correlated with the down-regulation of AP-1 DNA-binding activities. G. biloba extract was unique in its ability to inhibit the activation of c-Jun NH2-terminal protein kinase. CONCLUSIONS G. biloba extract might have its novel therapeutic effects on inflammation-based atherosclerotic diseases.
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Affiliation(s)
- Tien-Ping Tsao
- Division of Cardiology, Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, No 325, Section 2, Cheng-Kung Road, Neihu 114, Taipei, Taiwan, ROC
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7
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Winyard PG, Moody CJ, Jacob C. Oxidative activation of antioxidant defence. Trends Biochem Sci 2006; 30:453-61. [PMID: 15996871 DOI: 10.1016/j.tibs.2005.06.001] [Citation(s) in RCA: 178] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2005] [Revised: 05/19/2005] [Accepted: 06/21/2005] [Indexed: 02/02/2023]
Abstract
Living cells maintain a delicate balance between oxidizing and reducing species, and many disorders such as rheumatoid arthritis and Alzheimer's disease have been associated with a disturbed intracellular 'redox equilibrium'. The past few years have witnessed accelerated research into how natural redox responses and antioxidant defence systems are activated and how they restore a healthy redox balance. To function properly, many of these processes rely on a powerful sulfur redox chemistry, which is best exemplified by the complex, newly emerging cysteine-based redox regulation of the glutathione and thioredoxin pathways. Other redox systems based on oxidatively activated amino acid side chains in proteins are also becoming increasingly important, but are still barely understood or explored.
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Affiliation(s)
- Paul G Winyard
- Peninsula Medical School, Universities of Exeter and Plymouth, St. Luke's Campus, UK
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Kim H, Kim YN, Kim H, Kim CW. Oxidative stress attenuates Fas-mediated apoptosis in Jurkat T cell line through Bfl-1 induction. Oncogene 2004; 24:1252-61. [PMID: 15592513 DOI: 10.1038/sj.onc.1208282] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Many types of mammalian cells produce ROS in response to many different stimuli to modulate a number of cellular functions, including apoptosis. However, the correlation between ROS and apoptosis remains controversial, and the mechanisms whereby ROS-induced signals are propagated to critical downstream targets remain largely undefined. Here, we demonstrate that hydrogen peroxide (H2O2) upregulates the expression of Bfl-1, an antiapoptotic member of the Bcl-2 family, and that this is responsible for the antiapoptotic activity of ROS. When Jurkat, human leukemic T cells, were pretreated with 100 microM H2O2 and then treated with anti-Fas antibody, apoptosis was impaired without change of cell surface Fas expression. An investigation of the expression patterns of Bcl-2 family genes revealed that H2O2 treatment induced Bfl-1 gene expression, but left other genes unchanged, and this Bfl-1 expression and H2O2 -induced antiapoptotic effect was inhibited by antioxidants or NF-kappaB inhibitor. In addition, an electromobility shift assay revealed that the p65/p50 subunits of NF-kappaB activated by H2O2 bound to a bfl-1 promoter. Neither the induction of Bfl-1 nor the antiapoptotic effect of H2O2 was detected in Bfl-1-knockdown Jurkat cell line containing Bfl-1 antisense (Bfl-1AS). These data indicate that oxidative stress induces the expression of Bfl-1 via NF-kappaB activation, and this early-response gene protects cells from Fas-mediated apoptosis. This may be a cellular survival mechanism of cells exposed to phagocytes-derived ROS.
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Affiliation(s)
- Heejung Kim
- Department of Pathology, Tumor Immunity Medical Research Center and Cancer Research Institute, Seoul National University College of Medicine, 28 Yongon-dong, Chongno-gu, Seoul 110-799, Korea
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Chae HJ, Chae SW, Kim HR. N‐Acetyl Cysteine Regulates TNF‐α‐Inhibited Differentiation in ROS 17/2.8 Osteoblasts. Immunopharmacol Immunotoxicol 2004; 26:203-13. [PMID: 15209356 DOI: 10.1081/iph-120037716] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Osteoblasts play a pivotal role in bone remodeling. The alkaline phosphatase (ALPase) activity was decreased in ROS 17/2.8 osteoblast treated with TNF-alpha (2, 5 or 10 ng/ml). The treatment of TNF-alpha inhibited osteoblast differentiation such as ALPase activity in ROS 17/2.8 osteoblast. TNF-gamma (10 ng/ml) increased NF-kappaB DNA binding activity in nuclear extracts of osteoblasts. The addition of NAC (N-acetyl cysteine), free radical scavenger, completely prevented TNF-alpha-induced activation of NF-kappaB. In addition, IkappaB alpha and IkappaB beta were rapidly degraded, allowing the activated NF-kappaB to enter the nucleus and promote gene transcription. To determine whether IkappaB alpha signal transduction pathway is important in the differentiation, we generated IkappaB (KD)-stably transfected ROS 17/2.8 cells. These IkappaB (KD) transfectants did not show any regulation of ALPase in osteoblasts. Here, we suggest that the degradations of IkappaB alpha and IkappaB beta and the following activation of NF-kappaB are the targets of NAC and that NF-kappaB transcription factor is a pivotal clue to regulation of differentiation in TNFalpha-exposed osteoblasts.
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Affiliation(s)
- Han-Jung Chae
- Department of Pharmacology and Institute of Cardiovascular Research, School of Medicine, Chonbuk National University, Chonbuk, South Korea
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Cheng SM, Yang SP, Ho LJ, Tsao TP, Chang DM, Lai JH. Irbesartan inhibits human T-lymphocyte activation through downregulation of activator protein-1. Br J Pharmacol 2004; 142:933-42. [PMID: 15210574 PMCID: PMC1575109 DOI: 10.1038/sj.bjp.0705785] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2003] [Revised: 02/20/2004] [Accepted: 03/09/2004] [Indexed: 11/08/2022] Open
Abstract
1 Irbesartan is a promising antihypertensive drug with beneficial effects on atherosclerotic processes. In the progression of atherosclerosis, human T-lymphocytes play an important role, but it is not yet known how irbesartan modulates human T-lymphocytes activation. To gain insight into the mechanisms by which irbesartan acts, we investigated its effects on human T-lymphocytes. 2 Primary human T-lymphocytes were isolated from whole blood. Cytokines were determined by ELISA. Activator protein-1 (AP-1) and related protein activities were determined by electrophoretic mobility shift assays, kinase assays, Western blotting and transfection assays. 3 Irbesartan inhibited the production of both tumor necrosis factor-alpha and interferon-gamma by activated T-cells, especially at therapeutic concentrations. Further investigation at the molecular level indicated that the inhibition of activated human T-lymphocytes specifically correlated with the downregulation of AP-1 DNA-binding activity. In the Jurkat T-cell line, irbesartan also inhibited AP-1 transcriptional activity. Finally, we revealed that irbesartan is unique in its ability to inhibit the activation of both c-Jun NH2-terminal protein kinase and p38 MAPK. 4 Our studies show that irbesartan may modulate inflammation-based atherosclerotic diseases through a cell-mediated mechanism involving suppression of human T-lymphocytes activation via downregulation of AP-1 activity.
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Affiliation(s)
- Shu-Meng Cheng
- Division of Cardiology, Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, No 325, Section 2, Cheng-Kung Road, Neihu 114, Taipei, Taiwan, ROC
| | - Shih-Ping Yang
- Division of Cardiology, Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, No 325, Section 2, Cheng-Kung Road, Neihu 114, Taipei, Taiwan, ROC
| | - Ling-Jun Ho
- Division of Gerontology Research, National Health Research Institute, No 325, Section 2, Cheng-Kung Road, Neihu 114, Taipei, Taiwan, ROC
| | - Tien-Ping Tsao
- Division of Cardiology, Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, No 325, Section 2, Cheng-Kung Road, Neihu 114, Taipei, Taiwan, ROC
| | - Deh-Ming Chang
- Division of Rheumatology/Immunology & Allergy, Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, No 325, Section 2, Cheng-Kung Road, Neihu 114, Taipei, Taiwan, ROC
| | - Jenn-Haung Lai
- Division of Rheumatology/Immunology & Allergy, Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, No 325, Section 2, Cheng-Kung Road, Neihu 114, Taipei, Taiwan, ROC
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