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Abubakar M, Rasool HF, Javed I, Raza S, Abang L, Hashim MMA, Saleem Z, Abdullah RM, Faraz MA, Hassan KM, Bhat RR. Comparative Roles of IL-1, IL-6, IL-10, IL-17, IL-18, 1L-22, IL-33, and IL-37 in Various Cardiovascular Diseases With Potential Insights for Targeted Immunotherapy. Cureus 2023; 15:e42494. [PMID: 37637634 PMCID: PMC10455045 DOI: 10.7759/cureus.42494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/26/2023] [Indexed: 08/29/2023] Open
Abstract
In recent years, the study of interleukins (ILs), crucial cytokines involved in immune response and inflammation, has garnered significant attention within the sphere of cardiovascular diseases (CVDs). The research has provided insights into the involvement of ILs in diverse CVDs, including arrhythmias, myocardial infarction, atherosclerosis, and heart failure (HF). ILs have emerged as promising therapeutic targets for drug interventions through their involvement in disease development and progression. This comprehensive review provides a detailed overview of ILs, elucidating their functions within the immune system and offering insights into their specific contributions to various CVDs. Moreover, the article delves into the examination of current and potential drug therapies that selectively target ILs in the management of CVDs, presenting a comprehensive analysis of the advantages and disadvantages associated with these therapeutic approaches. A comprehensive literature review was conducted to investigate the involvement of ILs in CVDs. The relevant articles were searched on PubMed, PubMed Central, Medline, Cochrane, Google Scholar, and ScienceDirect databases. The search encompassed articles published from these databases' inception until July 12, 2023. We first examine generalized aspects of ILs, particularly CVDs. Then, we shift focus towards examining the direct impact of ILs on cardiac cells and tissue; on the immune system and inflammation; endothelial cells and vascular function; and finally, their interactions with other signaling pathways and molecules. Then, we discuss the molecular mechanisms of various ILs. Sequentially, we delve into a comprehensive analysis of the individualized role of each distinct IL in diverse CVDs, examining their specific contributions. Finally, we explore the potential for targeted drug therapy to modulate IL activity, aiming to enhance outcomes for patients burdened with CVD. The objective is the identification of gaps in current knowledge and highlight areas that require further investigation within the context of cardiovascular medicine. Through deepening our comprehension of the intricate involvement of ILs in CVDs and harnessing their potential for targeted drug therapy, novel treatment strategies can be devised, leading to improved patient outcomes in cardiovascular medicine.
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Affiliation(s)
- Muhammad Abubakar
- Department of Internal Medicine, Ameer-Ud-Din Medical College, Lahore General Hospital, Lahore, PAK
- Department of Internal Medicine, Siddique Sadiq Memorial Trust Hospital, Gujranwala, PAK
| | - Hafiz Fahad Rasool
- Department of Public Health, Nanjing Medical University School of Public Health, Nanjing, CHN
| | - Izzah Javed
- Department of Internal Medicine, Ameer-Ud-Din Medical College, Lahore General Hospital, Lahore, PAK
| | - Saud Raza
- Department of Internal Medicine, Ameer-Ud-Din Medical College, Lahore General Hospital, Lahore, PAK
| | - Lucy Abang
- Department of Biochemistry, All Saints University School of Medicine, Roseau, DMA
| | | | - Zartasha Saleem
- Department of Emergency Medicine, The University of Lahore Teaching Hospital, Lahore, PAK
| | | | - Muhammad Ahmad Faraz
- Department of Forensic Medicine, Post Graduate Medical Institute, Lahore General Hospital, Lahore, PAK
| | - Khawaja Mushammar Hassan
- Department of Internal Medicine, Ameer-Ud-Din Medical College, Lahore General Hospital, Lahore, PAK
| | - Rakshita Ramesh Bhat
- Department of Medical Oncology, Mangalore Institute of Oncology, Mangalore, IND
- Department of Internal Medicine, Bangalore Medical College and Research Institute, Bangalore, IND
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Groza Y, Jemelkova J, Kafkova LR, Maly P, Raska M. IL-6 and its role in IgA nephropathy development. Cytokine Growth Factor Rev 2022; 66:1-14. [PMID: 35527168 DOI: 10.1016/j.cytogfr.2022.04.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Accepted: 04/05/2022] [Indexed: 02/07/2023]
Abstract
IL-6 is considered one of the well characterized cytokines exhibiting homeostatic, pro- and anti-inflammatory activities, depending on the receptor variant and the induced intracellular cis- or trans-signaling responses. IL-6-activated pathways are involved in the regulation of cell proliferation, survival, differentiation, and cell metabolism changes. Deviations in IL-6 levels or abnormal response to IL-6 signaling are associated with several autoimmune diseases including IgA nephropathy (IgAN), one of most frequent primary glomerulonephritis worldwide. IgAN is associated with increased plasma concentration of IL-6 and increased plasma concentration of aberrantly galactosylated IgA1 immunoglobulin (Gd-IgA1). Gd-IgA1 is specifically recognized by autoantibodies, leading to the formation of circulating immune complexes (CIC) with nephritogenic potential, since CIC deposited in the glomerular mesangium induce mesangial cells proliferation and glomerular injury. Infection of the upper respiratory or digestive tract enhances IL-6 production and in IgAN patients is often followed by the macroscopic hematuria. This review recapitulates general aspects of IL-6 signaling and summarizes experimental evidences about IL-6 involvement in the etiopathogenesis of IgA nephropathy through the production of Gd-IgA1 and regulation of mesangial cell proliferation.
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Affiliation(s)
- Yaroslava Groza
- Laboratory of Ligand Engineering, Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV Research Center, Prumyslova 595, Vestec 252 50, Czech Republic
| | - Jana Jemelkova
- Department of Immunology, Faculty of Medicine and Dentistry, Palacky University Olomouc, Hnevotinska 3, Olomouc 779 00, Czech Republic
| | - Leona Raskova Kafkova
- Department of Immunology, Faculty of Medicine and Dentistry, Palacky University Olomouc, Hnevotinska 3, Olomouc 779 00, Czech Republic.
| | - Petr Maly
- Laboratory of Ligand Engineering, Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV Research Center, Prumyslova 595, Vestec 252 50, Czech Republic
| | - Milan Raska
- Department of Immunology, Faculty of Medicine and Dentistry, Palacky University Olomouc, Hnevotinska 3, Olomouc 779 00, Czech Republic.
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Ho CM, Lin KT, Shen R, Gu DL, Lee SS, Su WH, Jou YS. Prognostic comparative genes predict targets for sorafenib combination therapies in hepatocellular carcinoma. Comput Struct Biotechnol J 2022; 20:1752-1763. [PMID: 35495118 PMCID: PMC9024375 DOI: 10.1016/j.csbj.2022.04.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Revised: 04/05/2022] [Accepted: 04/05/2022] [Indexed: 11/17/2022] Open
Abstract
Large-scale comparative transcriptomics analysis of hepatocellular carcinoma reveals 664 prognostic comparative HCC (pcHCC) genes. pcHCC genes included novel targets with potential utility in sorafenib combination therapies. Knockdown of the selective pcHCC genes NCAPG and CENPW downregulated the p38/STAT3 axis to enhance sorafenib combination treatments.
With the increasing incidence and mortality of human hepatocellular carcinoma (HCC) worldwide, revealing innovative targets to improve therapeutic strategies is crucial for prolonging the lives of patients. To identify innovative targets, we conducted a comprehensive comparative transcriptome analysis of 5,410 human HCCs and 974 mouse liver cancers to identify concordantly expressed genes associated with patient survival. Among the 664 identified prognostic comparative HCC (pcHCC) genes, upregulated pcHCC genes were associated with prognostic clinical features, including large tumor size, vascular invasion and late HCC stages. Interestingly, after validating HCC patient prognoses in multiple independent datasets, we matched the 664 aberrant pcHCC genes with the sorafenib-altered genes in TCGA_LIHC patients and found these 664 pcHCC genes were enriched in sorafenib-related functions, such as downregulated xenobiotic and lipid metabolism and upregulated cell proliferation. Therapeutic agents targeting aberrant pcHCC genes presented divergent molecular mechanisms, including suppression of sorafenib-unrelated oncogenic pathways, induction of sorafenib-unrelated ferroptosis, and modulation of sorafenib transportation and metabolism, to potentiate sorafenib therapeutic effects in HCC combination therapy. Moreover, the pcHCC genes NCAPG and CENPW, which have not been targeted in combination with sorafenib treatment, were knocked down and combined with sorafenib treatment, which reduced HCC cell viability based on disruption to the p38/STAT3 axis, thereby hypersensitizing HCC cells. Together, our results provide important resources and reveal that 664 pcHCC genes represent innovative targets suitable for developing therapeutic strategies in combination with sorafenib based on the divergent synergistic mechanisms for HCC tumor suppression.
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Sueda Y, Okazaki R, Funaki Y, Hasegawa Y, Ishikawa H, Hirayama Y, Inui G, Harada T, Takata M, Morita M, Yamasaki A. Specialized Pro-Resolving Mediators Do Not Inhibit the Synthesis of Inflammatory Mediators Induced by Tumor Necrosis Factor-α in Synovial Fibroblasts. Yonago Acta Med 2022; 65:111-125. [DOI: 10.33160/yam.2022.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 03/04/2022] [Indexed: 11/05/2022]
Affiliation(s)
- Yuriko Sueda
- Division of Respiratory Medicine and Rheumatology, Department of Multidisciplinary Internal Medicine, School of Medicine, Faculty of Medicine, Tottori University, Yonago 683-8504, Japan
| | - Ryota Okazaki
- Division of Respiratory Medicine and Rheumatology, Department of Multidisciplinary Internal Medicine, School of Medicine, Faculty of Medicine, Tottori University, Yonago 683-8504, Japan
| | - Yoshihiro Funaki
- Division of Respiratory Medicine and Rheumatology, Department of Multidisciplinary Internal Medicine, School of Medicine, Faculty of Medicine, Tottori University, Yonago 683-8504, Japan
| | - Yasuyuki Hasegawa
- Rheumatology/ Collagen Disease Medicine, Tottori Prefectural Central Hospital, Tottori 680-0901, Japan
| | - Hiroki Ishikawa
- Division of Respiratory Medicine and Rheumatology, Department of Multidisciplinary Internal Medicine, School of Medicine, Faculty of Medicine, Tottori University, Yonago 683-8504, Japan
| | - Yuki Hirayama
- Division of Respiratory Medicine and Rheumatology, Department of Multidisciplinary Internal Medicine, School of Medicine, Faculty of Medicine, Tottori University, Yonago 683-8504, Japan
| | - Genki Inui
- Respiratory Medicine, National Hospital Organization Yonago Medical Center, Yonago 683-0006, Japan
| | - Tomoya Harada
- Division of Respiratory Medicine and Rheumatology, Department of Multidisciplinary Internal Medicine, School of Medicine, Faculty of Medicine, Tottori University, Yonago 683-8504, Japan
| | - Miki Takata
- Division of Respiratory Medicine and Rheumatology, Department of Multidisciplinary Internal Medicine, School of Medicine, Faculty of Medicine, Tottori University, Yonago 683-8504, Japan
| | - Masato Morita
- Division of Respiratory Medicine and Rheumatology, Department of Multidisciplinary Internal Medicine, School of Medicine, Faculty of Medicine, Tottori University, Yonago 683-8504, Japan
| | - Akira Yamasaki
- Division of Respiratory Medicine and Rheumatology, Department of Multidisciplinary Internal Medicine, School of Medicine, Faculty of Medicine, Tottori University, Yonago 683-8504, Japan
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Ergosta-7,9(11),22-trien-3β-ol Attenuates Inflammatory Responses via Inhibiting MAPK/AP-1 Induced IL-6/JAK/STAT Pathways and Activating Nrf2/HO-1 Signaling in LPS-Stimulated Macrophage-like Cells. Antioxidants (Basel) 2021; 10:antiox10091430. [PMID: 34573062 PMCID: PMC8464970 DOI: 10.3390/antiox10091430] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 09/02/2021] [Accepted: 09/04/2021] [Indexed: 12/15/2022] Open
Abstract
Chronic inflammation induces autoimmune disorders and chronic diseases. Several natural products activate nuclear factor erythroid 2-related factor 2 (Nrf2) signaling, attenuating inflammatory responses. Ergosta-7,9(11),22-trien-3β-ol (EK100) isolated from Cordyceps militaris showed anti-inflammatory and antioxidative activity, but those mechanisms are still unclear. This study is the first to investigate EK100 on antioxidant Nrf2 relative genes expression in LPS-stimulated macrophage-like cell lines. The results showed that EK100 reduced IL-6 (interleukin-6) and tumor necrosis factor-α production. EK100 also attenuated a mitogen-activated protein kinase/activator protein-1 (MAPK/AP-1) pathway and interleukin-6/Janus kinase/signal transducer and activator of transcription (IL-6/JAK/STAT) pathway in LPS-stimulated cells. Toll-like receptor 4 (TLR4) inhibitor CLI-095 and MAPK inhibitors can synergize the anti-inflammatory response of EK100 in LPS-stimulated cells. Moreover, EK100 activated Nrf2/HO-1 (heme oxygenase-1) signaling in LPS-stimulated murine macrophage-like RAW 264.7 cells, murine microglial BV2 cells, and human monocytic leukemia THP-1 cells. However, Nrf2 small interfering RNA (Nrf2 siRNA) reversed EK100-induced antioxidative proteins expressions. In conclusion, EK100 showed anti-inflammatory responses via activating the antioxidative Nrf2/HO-1 signaling and inhibiting TLR4 related MAPK/AP-1 induced IL-6/JAK/STAT pathways in the LPS-stimulated cells in vitro. The results suggest EK100 acts as a novel antioxidant with multiple therapeutic targets that can potentially be developed to treat chronic inflammation-related diseases.
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Lee PS, Chiou YS, Chou PY, Nagabhushanam K, Ho CT, Pan MH. 3'-Hydroxypterostilbene Inhibits 7,12-Dimethylbenz[a]anthracene (DMBA)/12-O-Tetradecanoylphorbol-13-Acetate (TPA)-Induced Mouse Skin Carcinogenesis. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2021; 81:153432. [PMID: 33310310 DOI: 10.1016/j.phymed.2020.153432] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/16/2020] [Accepted: 11/28/2020] [Indexed: 06/12/2023]
Abstract
BACKGROUND A natural pterostilbene analogue isolated from the herb Sphaerophysa salsula, 3'-hydroxypterostilbene (HPSB), exhibits antiproliferative activity in several cancer cell lines; however, the inhibitory effects of HPSB on skin carcinogenesis remains unclear. PURPOSE The aim of this study was to evaluate the inhibitory effects of HPSB on two-stage skin carcinogenesis in mice and its potential mechanism. STUDY DESIGN AND METHODS This study investigated the anti-inflammatory and anti-tumor effects of HPSB in the 12-O-tetradecanoylphorbol-13-acetate (TPA)-stimulated acute skin inflammation and 7,12-dimethylbenz[a]anthracene (DMBA)/TPA-induced two-stage skin carcinogenesis model. In addition, the effects of HPSB on the modulation of the phase I and phase II metabolizing enzymes in the DMBA-induced HaCaT cell model were investigated. RESULTS The results provide evidence that topical treatment with HPSB significantly inhibits TPA-induced epidermal hyperplasia and leukocyte infiltration through the down-regulation of cyclooxygenase-2 (COX-2), matrix metalloprotein-9 (MMP-9), and ornithine decarboxylase (ODC) protein expression in mouse skin. Furthermore, HPSB suppresses DMBA/TPA-induced skin tumor incidence and multiplicity via the inhibition of proliferating cell nuclear antigen (PCNA), Cyclin B1 and cyclin-dependent kinase 1 (CDK1) expression in the two-stage skin carcinogenesis model. In addition, pretreatment with HPSB markedly reduces DMBA-induced cytochrome P450 1A1 (CYP1A1) and cytochrome P450 1B1 (CYP1B1) gene expression in human keratinocytes; however, HPSB does not significantly affect the gene expression of the phase II enzymes. CONCLUSION This is the first study to show that topical treatment with HPSB prevents mouse skin tumorigenesis. Overall, our study suggests that natural HPSB may serve as a novel chemopreventive agent capable of preventing carcinogen activation and inflammation-associated tumorigenesis.
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Affiliation(s)
- Pei-Sheng Lee
- Institute of Food Science and Technology, National Taiwan University, Taipei 10617, Taiwan
| | - Yi-Shiou Chiou
- Institute of Food Science and Technology, National Taiwan University, Taipei 10617, Taiwan; Tsinghua Berkeley Shenzhen Institute (TBSI), Tsinghua University, Shenzhen, China
| | - Pin-Yu Chou
- Institute of Food Science and Technology, National Taiwan University, Taipei 10617, Taiwan
| | | | - Chi-Tang Ho
- Department of Food Science, Rutgers University, New Brunswick, New Jersey, USA
| | - Min-Hsiung Pan
- Institute of Food Science and Technology, National Taiwan University, Taipei 10617, Taiwan; Department of Medical Research, China Medical University Hospital, China Medical University, Taichung 40402, Taiwan; Department of Health and Nutrition Biotechnology, Asia University, Taichung, Taiwan.
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7
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Hoevenaar M, Goossens D, Roorda J. Angiotensin-converting enzyme 2, the complement system, the kallikrein-kinin system, type-2 diabetes, interleukin-6, and their interactions regarding the complex COVID-19 pathophysiological crossroads. J Renin Angiotensin Aldosterone Syst 2020; 21:1470320320979097. [PMID: 33283602 PMCID: PMC7724427 DOI: 10.1177/1470320320979097] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 11/11/2020] [Indexed: 12/15/2022] Open
Abstract
Because of the current COVID-19-pandemic, the world is currently being held hostage in various lockdowns. ACE2 facilitates SARS-CoV-2 cell-entry, and is at the very center of several pathophysiological pathways regarding the RAAS, CS, KKS, T2DM, and IL-6. Their interactions with severe COVID-19 complications (e.g. ARDS and thrombosis), and potential therapeutic targets for pharmacological intervention, will be reviewed.
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Affiliation(s)
| | | | - Janne Roorda
- Medical Doctor, General Practice
van Dijk, Oisterwijk, The Netherlands
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The constitutive activity of the viral-encoded G protein-coupled receptor US28 supports a complex signalling network contributing to cancer development. Biochem Soc Trans 2020; 48:1493-1504. [PMID: 32779712 PMCID: PMC7458396 DOI: 10.1042/bst20190988] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 07/05/2020] [Accepted: 07/14/2020] [Indexed: 12/23/2022]
Abstract
US28 is a viral G protein-coupled receptor (GPCR) encoded by the human cytomegalovirus (HCMV). This receptor, expressed both during lytic replication and viral latency, is required for latency. US28 is binding to a wide variety of chemokines but also exhibits a particularly high constitutive activity robustly modulating a wide network of cellular pathways altering the host cell environment to benefit HCMV infection. Several studies suggest that US28-mediated signalling may contribute to cancer progression. In this review, we discuss the unique structural characteristics that US28 acquired through evolution that confer a robust constitutive activity to this viral receptor. We also describe the wide downstream signalling network activated by this constitutive activation of US28 and discuss how these signalling pathways may promote and support important cellular aspects of cancer.
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Han J, Wu J, Silke J. An overview of mammalian p38 mitogen-activated protein kinases, central regulators of cell stress and receptor signaling. F1000Res 2020; 9. [PMID: 32612808 PMCID: PMC7324945 DOI: 10.12688/f1000research.22092.1] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/18/2020] [Indexed: 12/19/2022] Open
Abstract
The p38 family is a highly evolutionarily conserved group of mitogen-activated protein kinases (MAPKs) that is involved in and helps co-ordinate cellular responses to nearly all stressful stimuli. This review provides a succinct summary of multiple aspects of the biology, role, and substrates of the mammalian family of p38 kinases. Since p38 activity is implicated in inflammatory and other diseases, we also discuss the clinical implications and pharmaceutical approaches to inhibit p38.
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Affiliation(s)
- Jiahuai Han
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian, 361005, China
| | - Jianfeng Wu
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian, 361005, China
| | - John Silke
- The Walter and Eliza Hall Institute, IG Royal Parade, Parkville, Victoria, 3052, Australia.,Department of Medical Biology, University of Melbourne, Parkville, Victoria, 3050, Australia
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10
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Li Y, Ding H, Liu L, Song Y, Du X, Feng S, Wang X, Li X, Wang Z, Li X, Li J, Wu J, Liu G. Non-esterified Fatty Acid Induce Dairy Cow Hepatocytes Apoptosis via the Mitochondria-Mediated ROS-JNK/ERK Signaling Pathway. Front Cell Dev Biol 2020; 8:245. [PMID: 32411699 PMCID: PMC7198733 DOI: 10.3389/fcell.2020.00245] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Accepted: 03/24/2020] [Indexed: 12/30/2022] Open
Abstract
Elevated plasma non-esterified fatty acid (NEFA) levels and hepatocytes damage are characteristics of ketosis in dairy cows. Oxidative stress is associated with the pathogenesis of NEFA-induced liver damage. However, the exact mechanism by which oxidative stress mediates NEFA-induced hepatocytes apoptosis and liver injury remains poorly understood. The results of the present study demonstrated that NEFA contribute to reactive oxygen species (ROS) generation, resulting in an imbalance between oxidative and antioxidant species, transcriptional activation of p53, transcriptional inhibition of nuclear factor E2-related factor 2 (Nrf2), loss of mitochondria membrane potential (MMP) and release of apoptosis-inducing factor (AIF) and cytochrome c (cyt c) into the cytosol, leading to hepatocytes apoptosis. Besides, NEFA triggered apoptosis in dairy cow hepatocytes via the regulation of c-Jun N-terminal kinase (JNK), extracellular signal-regulated protein kinases 1 and 2 (ERK1/2), Bcl-2-associated X protein (Bax), B-cell lymphoma gene 2 (Bcl-2), caspase 9 and poly (ADP-ribose) polymerase (PARP). Pretreatment with the inhibitor SP600125 or PD98059 or the antioxidant N-acetylcysteine (NAC) revealed that NEFA-ROS-JNK/ERK-mediated mitochondrial signaling pathway plays a crucial role in NEFA-induced hepatocytes apoptosis. Moreover, the results suggested that the transcription factors p53 and Nrf2 function downstream of this NEFA-ROS-JNK/ERK pathway and are involved in NEFA-induced hepatocytes apoptosis. In conclusion, these findings indicate that the NEFA-ROS-JNK/ERK-mediated mitochondrial pathway plays an important role in NEFA-induced dairy cow hepatocytes apoptosis and strongly suggests that the inhibitors SP600125 and PD98059 and the antioxidant NAC may be developed as therapeutics to prevent hyperlipidemia-induced apoptotic damage in ketotic dairy cows.
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Affiliation(s)
- Yu Li
- College of Animal Science and Technology, Anhui Agricultural University, Hefei, China.,Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Hongyan Ding
- College of Animal Science and Technology, Anhui Agricultural University, Hefei, China
| | - Leihong Liu
- College of Animal Science and Technology, Anhui Agricultural University, Hefei, China
| | - Yuxiang Song
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Xiliang Du
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Shibin Feng
- College of Animal Science and Technology, Anhui Agricultural University, Hefei, China
| | - Xichun Wang
- College of Animal Science and Technology, Anhui Agricultural University, Hefei, China
| | - Xiaobing Li
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Zhe Wang
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Xinwei Li
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Jinchun Li
- College of Animal Science and Technology, Anhui Agricultural University, Hefei, China
| | - Jinjie Wu
- College of Animal Science and Technology, Anhui Agricultural University, Hefei, China
| | - Guowen Liu
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
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11
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Philipp J, Azimzadeh O, Subramanian V, Merl-Pham J, Lowe D, Hladik D, Erbeldinger N, Ktitareva S, Fournier C, Atkinson MJ, Raj K, Tapio S. Radiation-Induced Endothelial Inflammation Is Transferred via the Secretome to Recipient Cells in a STAT-Mediated Process. J Proteome Res 2017; 16:3903-3916. [PMID: 28849662 DOI: 10.1021/acs.jproteome.7b00536] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Radiation is the most common treatment of cancer. Minimizing the normal tissue injury, especially the damage to vascular endothelium, remains a challenge. This study aimed to analyze direct and indirect radiation effects on the endothelium by investigating mechanisms of signal transfer from irradiated to nonirradiated endothelial cells by means of secreted proteins. Human coronary artery endothelial cells (HCECest2) undergo radiation-induced senescence in vitro 14 days after exposure to 10 Gy X-rays. Proteomics analysis was performed on HCECest2 14 days after irradiation with X-ray doses of 0 Gy (control) or 10 Gy using label-free technology. Additionally, the proteomes of control and radiation-induced secretomes, and those of nonirradiated HCECest2 exposed for 24 h to secreted proteins of either condition were measured. Key changes identified by proteomics and bioinformatics were validated by immunoblotting, ELISA, bead-based multiplex assays, and targeted transcriptomics. The irradiated cells, their secretome, and the nonirradiated recipient cells showed similar inflammatory response, characterized by induction of interferon type I-related proteins and activation of the STAT3 pathway. These data indicate that irradiated endothelial cells may adversely affect nonirradiated surrounding cells via senescence-associated secretory phenotype. This study adds to our knowledge of the pathological background of radiation-induced cardiovascular disease.
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Affiliation(s)
- Jos Philipp
- Helmholtz Zentrum München - German Research Center for Environmental Health GmbH, Institute of Radiation Biology , D-85764 Neuherberg, Germany
| | - Omid Azimzadeh
- Helmholtz Zentrum München - German Research Center for Environmental Health GmbH, Institute of Radiation Biology , D-85764 Neuherberg, Germany
| | - Vikram Subramanian
- Helmholtz Zentrum München - German Research Center for Environmental Health GmbH, Institute of Radiation Biology , D-85764 Neuherberg, Germany
| | - Juliane Merl-Pham
- Helmholtz Zentrum München - German Research Centre for Environmental Health, Research Unit Protein Science , D-80939 Munich, Germany
| | - Donna Lowe
- Biological Effects Department, Centre for Radiation, Chemicals and Environmental Hazards, Public Health England , OX11 0RQ Chilton, United Kingdom
| | - Daniela Hladik
- Helmholtz Zentrum München - German Research Center for Environmental Health GmbH, Institute of Radiation Biology , D-85764 Neuherberg, Germany
| | - Nadine Erbeldinger
- GSI Helmholtz Zentrum für Schwerionenforschung , 64291 Darmstadt, Germany
| | - Svetlana Ktitareva
- GSI Helmholtz Zentrum für Schwerionenforschung , 64291 Darmstadt, Germany
| | - Claudia Fournier
- GSI Helmholtz Zentrum für Schwerionenforschung , 64291 Darmstadt, Germany
| | - Michael J Atkinson
- Helmholtz Zentrum München - German Research Center for Environmental Health GmbH, Institute of Radiation Biology , D-85764 Neuherberg, Germany
| | - Ken Raj
- Biological Effects Department, Centre for Radiation, Chemicals and Environmental Hazards, Public Health England , OX11 0RQ Chilton, United Kingdom
| | - Soile Tapio
- Helmholtz Zentrum München - German Research Center for Environmental Health GmbH, Institute of Radiation Biology , D-85764 Neuherberg, Germany
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12
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Kagan P, Sultan M, Tachlytski I, Safran M, Ben-Ari Z. Both MAPK and STAT3 signal transduction pathways are necessary for IL-6-dependent hepatic stellate cells activation. PLoS One 2017; 12:e0176173. [PMID: 28472150 PMCID: PMC5417441 DOI: 10.1371/journal.pone.0176173] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 04/06/2017] [Indexed: 12/16/2022] Open
Abstract
Background During liver injury, hepatic stellate cells (HSCs) can undergo activation and transform into alpha-smooth muscle actin (αSMA)-expressing contractile myofibroblast-like cells, leading to deposition of excessive scar matrix. We have recently demonstrated that depletion of adenosine deaminase acting on double-stranded RNA (ADAR1) from mouse hepatocytes leads to HSC activation and induction of inflammation and hepatic fibrosis that is mediated by interleukin 6 (IL-6). Our aim was to identify and characterize the molecular pathways involved in the direct, inflammation-independent activation of HSCs by IL-6. Methods Primary HSCs were isolated from mouse livers. mRNA levels of αSMA and Col1a were analyzed using qRT-PCR. Protein levels of αSMA, MAPK, p-MAPK, p38, p-p38, STAT3 and p-STAT3 were assessed by Western Blot analysis. The effect of specific signal transduction pathway inhibitors (i.e., SB203580 (P-38 inhibitor), U0126 (MAPK inhibitor), S3I-201 (STAT3 inhibitor) and Ruxolitinib (Jak1/2 inhibitor)) was also studied. Results Primary HSCs treated with IL-6 demonstrated upregulation of αSMA and Col1a mRNA levels as well as increased αSMA protein levels. Moreover, the phenotypic transition of quiescent HSCs toward myofibroblast-like cells was noted upon administration of IL-6 and not in untreated samples. In addition, the phosphorylation levels of p38, MAPK and STAT3 increased 30 minutes after treatment, and was followed by a decline in the phosphorylation levels 2–4 hours post-treatment. However, addition of specific signal transduction pathway inhibitors curbed this effect, and resulted in αSMA and Col1a expression levels similar to those measured in untreated control samples. Conclusion IL-6 can directly induce the transition of HSCs toward myofibroblast-like cells. The effect is mediated by the activation of both MAPK and JAK/STAT signaling pathways. Elimination of either MAPK or JAK/STAT signaling pathways inhibits HSC stimulation. These results might pave the road toward the development of potential therapeutic interventions for hepatic fibrosis.
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Affiliation(s)
- Polina Kagan
- Liver Research Laboratory, Sheba Medical Center, Ramat Gan, Israel
- The Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Maya Sultan
- Liver Research Laboratory, Sheba Medical Center, Ramat Gan, Israel
| | - Irina Tachlytski
- Liver Research Laboratory, Sheba Medical Center, Ramat Gan, Israel
| | - Michal Safran
- Liver Research Laboratory, Sheba Medical Center, Ramat Gan, Israel
| | - Ziv Ben-Ari
- Liver Research Laboratory, Sheba Medical Center, Ramat Gan, Israel
- The Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
- Liver Disease Center, Sheba Medical Center, Ramat Gan, Israel
- * E-mail:
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Xie H, Li C, Dang Q, Chang LS, Li L. Infiltrating mast cells increase prostate cancer chemotherapy and radiotherapy resistances via modulation of p38/p53/p21 and ATM signals. Oncotarget 2016; 7:1341-53. [PMID: 26625310 PMCID: PMC4811464 DOI: 10.18632/oncotarget.6372] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Accepted: 11/06/2015] [Indexed: 12/11/2022] Open
Abstract
Early studies indicated that mast cells in prostate tumor microenvironment might influence prostate cancer (PCa) progression. Their impacts to PCa therapy, however, remained unclear. Here we found PCa could recruit more mast cells than normal prostate epithelial cells then alter PCa chemotherapy and radiotherapy sensitivity, leading to PCa more resistant to these therapies. Mechanism dissection revealed that infiltrated mast cells could increase p21 expression via modulation of p38/p53 signals, and interrupting p38-p53 signals via siRNAs of p53 or p21 could reverse mast cell-induced docetaxel chemotherapy resistance of PCa. Furthermore, recruited mast cells could also increase the phosphorylation of ATM at ser-1981 site, and inhibition of ATM activity could reverse mast cell-induced radiotherapy resistance. The in vivo mouse model with xenografted PCa C4-2 cells co-cultured with mast cells also confirmed that mast cells could increase PCa chemotherapy resistance via activating p38/p53/p21 signaling. Together, our results provide a new mechanism showing infiltrated mast cells could alter PCa chemotherapy and radiotherapy sensitivity via modulating the p38/p53/p21 signaling and phosphorylation of ATM. Targeting this newly identified signaling may help us better suppress PCa chemotherapy and radiotherapy resistance.
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Affiliation(s)
- Hongjun Xie
- Chawnshang Chang Sex Hormone Research Center, Department of Urology, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710061, China
| | - Chong Li
- CAS Key Laboratory of Infection and Immunity, Institute of Biophysics, Chinese Academy of Science, Beijing 100101, China
| | - Qiang Dang
- Chawnshang Chang Sex Hormone Research Center, Department of Urology, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710061, China
| | - Luke S Chang
- Chawnshang Chang Sex Hormone Research Center, Department of Urology, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710061, China
| | - Lei Li
- Chawnshang Chang Sex Hormone Research Center, Department of Urology, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710061, China
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Kaur T, Borse V, Sheth S, Sheehan K, Ghosh S, Tupal S, Jajoo S, Mukherjea D, Rybak LP, Ramkumar V. Adenosine A1 Receptor Protects Against Cisplatin Ototoxicity by Suppressing the NOX3/STAT1 Inflammatory Pathway in the Cochlea. J Neurosci 2016; 36:3962-77. [PMID: 27053204 PMCID: PMC4821909 DOI: 10.1523/jneurosci.3111-15.2016] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Revised: 02/16/2016] [Accepted: 02/26/2016] [Indexed: 01/19/2023] Open
Abstract
Cisplatin is a commonly used antineoplastic agent that produces ototoxicity that is mediated in part by increasing levels of reactive oxygen species (ROS) via the NOX3 NADPH oxidase pathway in the cochlea. Recent studies implicate ROS generation in mediating inflammatory and apoptotic processes and hearing loss by activating signal transducer and activator of transcription (STAT1). In this study, we show that the adenosine A1 receptor (A1AR) protects against cisplatin ototoxicity by suppressing an inflammatory response initiated by ROS generation via NOX3 NADPH oxidase, leading to inhibition of STAT1. Trans-tympanic administration of the A1AR agonist R-phenylisopropyladenosine (R-PIA) inhibited cisplatin-induced ototoxicity, as measured by auditory brainstem responses and scanning electron microscopy in male Wistar rats. This was associated with reduced NOX3 expression, STAT1 activation, tumor necrosis factor-α (TNF-α) levels, and apoptosis in the cochlea. In vitro studies in UB/OC-1 cells, an organ of Corti immortalized cell line, showed that R-PIA reduced cisplatin-induced phosphorylation of STAT1 Ser(727) (but not Tyr(701)) and STAT1 luciferase activity by suppressing the ERK1/2, p38, and JNK mitogen-activated protein kinase (MAPK) pathways.R-PIA also decreased the expression of STAT1 target genes, such as TNF-α, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) and reduced cisplatin-mediated apoptosis. These data suggest that the A1AR provides otoprotection by suppressing NOX3 and inflammation in the cochlea and could serve as an ideal target for otoprotective drug therapy. SIGNIFICANCE STATEMENT Cisplatin is a widely used chemotherapeutic agent for the treatment of solid tumors. Its use results in significant and permanent hearing loss, for which no US Food and Drug Administration-approved treatment is currently available. In this study, we targeted the cochlear adenosine A1 receptor (A1AR) by trans-tympanic injections of the agonist R-phenylisopropyladenosine (R-PIA) and showed that it reduced cisplatin-induced inflammation and apoptosis in the rat cochlea and preserved hearing. The mechanism of protection involves suppression of the NOX3 NADPH oxidase enzyme, a major target of cisplatin-induced reactive oxygen species (ROS) generation in the cochlea. ROS initiates an inflammatory and apoptotic cascade in the cochlea by activating STAT1 transcription factor, which is attenuated byR-PIA. Therefore, trans-tympanic delivery of A1AR agonists could effectively treat cisplatin ototoxicity.
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Affiliation(s)
- Tejbeer Kaur
- Department of Otolaryngology, Washington University School of Medicine, St. Louis, Missouri 63110, and
| | | | | | - Kelly Sheehan
- Department of Surgery, Southern Illinois University School of Medicine, Springfield, Illinois 62794
| | | | | | | | - Debashree Mukherjea
- Department of Surgery, Southern Illinois University School of Medicine, Springfield, Illinois 62794
| | - Leonard P Rybak
- Department of Pharmacology and Department of Surgery, Southern Illinois University School of Medicine, Springfield, Illinois 62794
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Cawyer C, Afroze SH, Drever N, Allen S, Jones R, Zawieja DC, Kuehl T, Uddin MN. Attenuation of hyperglycemia-induced apoptotic signaling and anti-angiogenic milieu in cultured cytotrophoblast cells. Hypertens Pregnancy 2016; 35:159-69. [PMID: 26930265 DOI: 10.3109/10641955.2015.1122035] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE Preeclampsia (preE) is a hypertensive disorder that occurs 20% in diabetic pregnancy. We have shown that hyperglycemia impairs cytotrophoblast cell (CTB) function. In this study, we assess apoptotic and anti-angiogenic signaling in excess glucose-induced CTBs. STUDY DESIGN Human extravillous CTBs (Sw. 71) were treated with 100, 150, 200, 300, or 400 mg/dL glucose for 48 h. Some cells were pretreated with a p38 inhibitor (SB203580) or a peroxisome proliferator-activated receptor gamma (PPARγ) ligand (rosiglitazone) or with D-mannitol. Cell lysates were utilized to measure p38 MAPK phosphorylation, PPARγ, Bcl-2-associated-X protein (Bax), anti-apoptotic Bcl-2, caspase-9, and cyclooxygenase-2 (Cox-2) expression by western blot. Levels of the vascular endothelial growth factor (VEGF), placental growth factor (PlGF), soluble fms-like tyrosine kinase-1 (sFlt-1), soluble endoglin (sEng), and interleukin 6 (IL-6) were measured in culture media using ELISA kits. Statistical comparisons were performed using analysis of variance with Duncan's post hoc test. RESULTS p38 phosphorylation and PPARγ were upregulated (p < 0.05) in CTBs treated with ≥150 mg/dL glucose compared to basal (100 mg/dL). Expressions of Bax/Bcl-2, Cox-2, and caspase-9 were upregulated (p < 0.05) in CTBs treated with ≥150 mg/dL glucose. Secretion of sFlt-1, sEng, and IL-6 was increased while VEGF and PIGF were decreased in CTB-treated ≥150 mg/dl of glucose (*p < 0.01 for each). SB203580 or rosiglitazone pretreatment significantly attenuated hyperglycemia-induced apoptotic and anti-angiogenic signaling. D-Mannitol had no effect. CONCLUSION Hyperglycemia induced apoptotic and anti-angiogenic signaling in CTBs. The observed diminution of hyperglycemia-induced signaling by SB203580 or rosiglitazone pretreatment suggests the involvement of apoptotic and anti-angiogenic signaling in CTB dysfunction.
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Affiliation(s)
- Chase Cawyer
- a Departments of Obstetrics & Gynecology , Texas A&M Health Science Center College of Medicine/Baylor Scott & White Health , Temple , Texas , USA
| | - Syeda H Afroze
- b Medical Physiology , Texas A&M Health Science Center College of Medicine/Baylor Scott & White Health , Temple , Texas , USA
| | - Nathan Drever
- a Departments of Obstetrics & Gynecology , Texas A&M Health Science Center College of Medicine/Baylor Scott & White Health , Temple , Texas , USA
| | - Steven Allen
- a Departments of Obstetrics & Gynecology , Texas A&M Health Science Center College of Medicine/Baylor Scott & White Health , Temple , Texas , USA
| | - Richard Jones
- a Departments of Obstetrics & Gynecology , Texas A&M Health Science Center College of Medicine/Baylor Scott & White Health , Temple , Texas , USA
| | - David C Zawieja
- b Medical Physiology , Texas A&M Health Science Center College of Medicine/Baylor Scott & White Health , Temple , Texas , USA
| | - Thomas Kuehl
- a Departments of Obstetrics & Gynecology , Texas A&M Health Science Center College of Medicine/Baylor Scott & White Health , Temple , Texas , USA.,c Pediatrics , Texas A&M Health Science Center College of Medicine/Baylor Scott & White Health , Temple , Texas , USA
| | - M Nasir Uddin
- a Departments of Obstetrics & Gynecology , Texas A&M Health Science Center College of Medicine/Baylor Scott & White Health , Temple , Texas , USA.,c Pediatrics , Texas A&M Health Science Center College of Medicine/Baylor Scott & White Health , Temple , Texas , USA.,d Internal Medicine , Texas A&M Health Science Center College of Medicine/Baylor Scott & White Health , Temple , Texas , USA
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Wilson RM, Messaoudi I. The impact of maternal obesity during pregnancy on offspring immunity. Mol Cell Endocrinol 2015; 418 Pt 2:134-42. [PMID: 26232506 PMCID: PMC4674375 DOI: 10.1016/j.mce.2015.07.028] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Revised: 06/28/2015] [Accepted: 07/27/2015] [Indexed: 12/19/2022]
Abstract
In the United States, approximately 64% of women of childbearing age are either overweight or obese. Maternal obesity during pregnancy is associated with a greater risk for adverse maternal-fetal outcomes. Adverse health outcomes for the offspring can persist into adulthood, increasing the incidence of several chronic conditions including cardiovascular disease, diabetes, and asthma. Since these diseases have a significant inflammatory component, these observations are indicative of perturbation of the normal development and maturation of the immune system of the offspring in utero. This hypothesis is strongly supported by data from several rodent studies. Although the mechanisms of these perturbations are not fully understood, it is thought that increased placental inflammation due to obesity may directly affect neonatal development through alterations in nutrient transport. In this review we examine the impact of maternal obesity on the neonatal immune system, and potential mechanisms for the changes observed.
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Affiliation(s)
- Randall M Wilson
- Graduate Program in Cell, Molecular, and Developmental Biology, University of California, Riverside, USA
| | - Ilhem Messaoudi
- Graduate Program in Cell, Molecular, and Developmental Biology, University of California, Riverside, USA; Division of Biomedical Sciences, School of Medicine, University of California, Riverside, USA.
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17
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Madaro L, Latella L. Forever young: rejuvenating muscle satellite cells. Front Aging Neurosci 2015; 7:37. [PMID: 25954192 PMCID: PMC4404872 DOI: 10.3389/fnagi.2015.00037] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 03/04/2015] [Indexed: 01/08/2023] Open
Abstract
A hallmark of aging is alteration of organismal homeostasis and progressive decline of tissue functions. Alterations of both cell intrinsic functions and regenerative environmental cues contribute to the compromised stem cell activity and reduced regenerative capability occurring in aged muscles. In this perspective, we discuss the new evidence supporting the hypothesis that skeletal muscle stem cells (MuSCs) are intrinsically defective in elderly muscles. In particular, we review three recent papers leading to identify fibroblast growth factor receptor-1, p38 mitogen-activated protein kinase, and p16INK4a as altered signaling in satellite cells from aged mice. These pathways contribute to age-related loss of MuSCs asymmetric polarization, compromised self-renewal capacity, and acquisition of pre-senescent state. The pharmacological manipulation of those networks can open novel strategies to rejuvenate MuSCs and counteract the functional decline of skeletal muscle during aging.
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Affiliation(s)
- Luca Madaro
- Epigenetics and Regenerative Medicine, IRCCS Fondazione Santa Lucia Rome, Italy ; Institute of Cell Biology and Neurobiology, National Research Council of Italy Rome, Italy
| | - Lucia Latella
- Epigenetics and Regenerative Medicine, IRCCS Fondazione Santa Lucia Rome, Italy ; Institute of Translational Pharmacology, National Research Council of Italy Rome, Italy
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18
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Cawyer CR, Horvat D, Leonard D, Allen SR, Jones RO, Zawieja DC, Kuehl TJ, Uddin MN. Hyperglycemia impairs cytotrophoblast function via stress signaling. Am J Obstet Gynecol 2014; 211:541.e1-8. [PMID: 24793974 DOI: 10.1016/j.ajog.2014.04.033] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 03/28/2014] [Accepted: 04/28/2014] [Indexed: 12/11/2022]
Abstract
OBJECTIVE Diabetes mellitus is a risk factor for preeclampsia. Cytotrophoblast (CTB) invasion is facilitated from the conversion of plasminogen to plasmin by urokinase plasminogen activator (uPA), regulated by plasminogen activator inhibitor 1 (PAI-1), and may be inhibited in preeclampsia. This study assessed signaling mechanisms of hyperglycemia-induced CTB dysfunction. STUDY DESIGN Human CTBs were treated with 45, 135, 225, 495, or 945 mg/dL glucose for 48 hours. Some cells were pretreated with a p38 inhibitor (SB203580) or a peroxisome proliferator-activated receptor-gamma (PPAR-γ) ligand (rosiglitazone). Expression of uPA, PAI-1, and PPAR-γ levels and p38 mitogen-activated protein kinase phosphorylation were measured by Western blot in cell lysates. Messenger ribonucleic acid of uPA and PAI-1 was measured by quantitative polymerase chain reaction. Levels of interleukin-6, angiogenic (vascular endothelial growth factor [VEGF], placenta growth factor [PlGF]) and antiangiogenic factors (soluble fms-like tyrosine kinase-1 [sFlt-1], soluble endoglin [sEng]) were measured in the media by enzyme-linked immunosorbent assay kits. Statistical comparisons were performed using analysis of variance with a Duncan's post-hoc test. RESULTS Both uPA and PAI-1 protein and messenger ribonucleic acid were down-regulated (P < .05) in CTBs treated with 135 mg/dL glucose or greater compared with basal (45 mg/dL). The sEng, sFlt-1, and interleukin-6 were up-regulated, whereas the VEGF and PlGF were down-regulated by 135 mg/dL glucose or greater. p38 phosphorylation and PPAR-γ were up-regulated (P < .05) in hyperglycemia-treated CTBs. The SB203580 or rosiglitazone pretreatment showed an attenuation of glucose-induced down-regulation of uPA and PAI-1. CONCLUSION Hyperglycemia disrupts the invasive profile of CTB by decreasing uPA and PAI-1 expression; down-regulating VEGF and PlGF; and up-regulating sEng, sFlt-1, and interleukin-6. Attenuation of CTB dysfunction by SB203580 or rosiglitazone pretreatment suggests the involvement of stress signaling.
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Affiliation(s)
- Chase R Cawyer
- Department of Obstetrics and Gynecology, Scott and White Healthcare/Texas A&M Health Science Center College of Medicine, Temple, TX
| | - Darijana Horvat
- Department of Obstetrics and Gynecology, Scott and White Healthcare/Texas A&M Health Science Center College of Medicine, Temple, TX
| | | | - Steven R Allen
- Department of Obstetrics and Gynecology, Scott and White Healthcare/Texas A&M Health Science Center College of Medicine, Temple, TX
| | - Richard O Jones
- Department of Obstetrics and Gynecology, Scott and White Healthcare/Texas A&M Health Science Center College of Medicine, Temple, TX
| | - David C Zawieja
- Department of Medical Physiology, Scott and White Healthcare/Texas A&M Health Science Center College of Medicine, Temple, TX
| | - Thomas J Kuehl
- Department of Obstetrics and Gynecology, Scott and White Healthcare/Texas A&M Health Science Center College of Medicine, Temple, TX
| | - Mohammad N Uddin
- Department of Obstetrics and Gynecology, Scott and White Healthcare/Texas A&M Health Science Center College of Medicine, Temple, TX.
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Mohan CD, Bharathkumar H, Bulusu KC, Pandey V, Rangappa S, Fuchs JE, Shanmugam MK, Dai X, Li F, Deivasigamani A, Hui KM, Kumar AP, Lobie PE, Bender A, Basappa, Sethi G, Rangappa KS. Development of a novel azaspirane that targets the Janus kinase-signal transducer and activator of transcription (STAT) pathway in hepatocellular carcinoma in vitro and in vivo. J Biol Chem 2014; 289:34296-307. [PMID: 25320076 DOI: 10.1074/jbc.m114.601104] [Citation(s) in RCA: 140] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Signal transducer and activator of transcription 3 (STAT3) is a transcription factor that regulates genes involved in cell growth, proliferation, and survival, and given its association with many types of cancers, it has recently emerged as a promising target for therapy. In this work, we present the synthesis of N-substituted azaspirane derivatives and their biological evaluation against hepatocellular carcinoma (HCC) cells (IC50 = 7.3 μm), thereby identifying 2-(1-(4-(2-cyanophenyl)1-benzyl-1H-indol-3-yl)-5-(4-methoxy-phenyl)-1-oxa-3-azaspiro(5,5) undecane (CIMO) as a potent inhibitor of the JAK-STAT pathway with selectivity over normal LO2 cells (IC50 > 100 μm). The lead compound, CIMO, suppresses proliferation of HCC cells and achieves this effect by reducing both constitutive and inducible phosphorylation of JAK1, JAK2, and STAT3. Interestingly, CIMO displayed inhibition of Tyr-705 phosphorylation, which is required for nuclear translocation of STAT3, but it has no effect on Ser-727 phosphorylation. CIMO accumulates cancer cells in the sub-G1 phase and decreases STAT3 in the nucleus and thereby causes down-regulation of genes regulated via STAT3. Suppression of STAT3 phosphorylation by CIMO and knockdown of STAT3 mRNA using siRNA transfection displayed a similar effect on the viability of HCC cells. Furthermore, CIMO significantly decreased the tumor development in an orthotopic HCC mouse model through the modulation of phospho-STAT3, Ki-67, and cleaved caspase-3 in tumor tissues. Thus, CIMO represents a chemically novel and biologically in vitro and in vivo validated compound, which targets the JAK-STAT pathway as a potential cancer treatment.
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Affiliation(s)
| | - Hanumantharayappa Bharathkumar
- the Laboratory of Chemical Biology, Department of Chemistry, Bangalore University, Central College Campus, Palace Road, Bangalore 560001, India
| | - Krishna C Bulusu
- the Centre for Molecular Science Informatics, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Vijay Pandey
- the Cancer Science Institute of Singapore, National University of Singapore, Singapore 117599
| | - Shobith Rangappa
- the Frontier Research Center for Post-genome Science and Technology Hokkaido University, Japan
| | - Julian E Fuchs
- the Centre for Molecular Science Informatics, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Muthu K Shanmugam
- the Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore, and
| | - Xiaoyun Dai
- the Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore, and
| | - Feng Li
- the Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore, and
| | - Amudha Deivasigamani
- the Division of Cellular and Molecular Research, Humphrey Oei Institute of Cancer Research, National Cancer Centre, Singapore 169610, Singapore
| | - Kam M Hui
- the Division of Cellular and Molecular Research, Humphrey Oei Institute of Cancer Research, National Cancer Centre, Singapore 169610, Singapore
| | - Alan Prem Kumar
- the Cancer Science Institute of Singapore, National University of Singapore, Singapore 117599, the Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore, and
| | - Peter E Lobie
- the Cancer Science Institute of Singapore, National University of Singapore, Singapore 117599, the Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore, and
| | - Andreas Bender
- the Centre for Molecular Science Informatics, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Basappa
- the Laboratory of Chemical Biology, Department of Chemistry, Bangalore University, Central College Campus, Palace Road, Bangalore 560001, India,
| | - Gautam Sethi
- the Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore, and
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Interleukin-6 drives melanoma cell motility through p38α-MAPK-dependent up-regulation of WNT5A expression. Mol Oncol 2014; 8:1365-78. [PMID: 24954857 PMCID: PMC5528610 DOI: 10.1016/j.molonc.2014.05.008] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Revised: 05/03/2014] [Accepted: 05/19/2014] [Indexed: 12/24/2022] Open
Abstract
Extensive research has demonstrated a tumor-promoting role of increased WNT5A expression in malignant melanoma. However, very little light has been shed upon how WNT5A expression is up-regulated in melanoma. A potential regulator of WNT5A expression is the pro-inflammatory cytokine Interleukin (IL)-6, which shares the ability of WNT5A to increase melanoma cell invasion. Here, we investigate whether IL-6 can promote melanoma cell motility through an increased expression of WNT5A. We clearly demonstrate that the WNT5A-antagonistic peptide Box5 could inhibit IL-6-induced melanoma cell migration and invasion. Furthermore, IL-6 stimulation of the human melanoma cell lines HTB63 and A375 increased the expression of WNT5A in a dose-dependent manner. To identify the signaling mechanism responsible for this up-regulation, we explored the involvement of the three main signals induced by IL-6; STAT3, Akt and ERK 1/2. Of these, only STAT3 was activated by IL-6 in the melanoma cell lines tested. However, the STAT3 inhibitor S3I-201 failed to inhibit IL-6-induced WNT5A up-regulation in HTB63 and A375 cells. Nor did STAT3 siRNA silencing affect the expression of WNT5A. In search of an alternative signaling mechanism, we detected IL-6-induced activation of p38-MAPK in HTB63 and A375 cells. The p38-MAPK inhibitor SB203580 abolished the IL-6-induced WNT5A up-regulation and blocked IL-6-induced melanoma cell invasion. The latter effect could be rescued by the addition of recombinant WNT5A. Notably, immunoprecipitation analysis revealed that only the p38α-MAPK isoform was activated by IL-6, and subsequent siRNA silencing of p38α-MAPK abolished the IL-6-induced up-regulation of WNT5A. Taken together, we demonstrate a novel link between the two melanoma pro-metastatic agents IL-6 and WNT5A explaining how IL-6 can increase melanoma cell invasion and thus promote the metastatic process. This finding provides a basis for future therapeutic intervention of melanoma progression.
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Sethi G, Chatterjee S, Rajendran P, Li F, Shanmugam MK, Wong KF, Kumar AP, Senapati P, Behera AK, Hui KM, Basha J, Natesh N, Luk JM, Kundu TK. Inhibition of STAT3 dimerization and acetylation by garcinol suppresses the growth of human hepatocellular carcinoma in vitro and in vivo. Mol Cancer 2014; 13:66. [PMID: 24655440 PMCID: PMC3998115 DOI: 10.1186/1476-4598-13-66] [Citation(s) in RCA: 138] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Accepted: 03/12/2014] [Indexed: 02/06/2023] Open
Abstract
Background Constitutive activation of signal transducer and activator of transcription 3 (STAT3) has been linked with proliferation, survival, invasion and angiogenesis of a variety of human cancer cells, including hepatocellular carcinoma (HCC). Thus, novel agents that can suppress STAT3 activation have potential for both prevention and treatment of HCC. Here we report, garcinol, a polyisoprenylated benzophenone, could suppress STAT3 activation in HCC cell lines and in xenografted tumor of HCC in nude mice model. Experimental design Different HCC cell lines have been treated with garcinol and the inhibition of STAT3 activation, dimerization and acetylation have been checked by immunoblotting, immuno-fluorescence, and DNA binding assays. Xenografted tumor model has been generated in nude mice using HCC cell line and effect of garcinol in the inhibition of tumor growth has been investigated. Results Garcinol could inhibit both constitutive and interleukin (IL-6) inducible STAT3 activation in HCC cells. Computational modeling showed that garcinol could bind to the SH2 domain of STAT3 and suppress its dimerization in vitro. Being an acetyltransferase inhibitor, garcinol also inhibits STAT3 acetylation and thus impairs its DNA binding ability. The inhibition of STAT3 activation by garcinol led to the suppression of expression of various genes involved in proliferation, survival, and angiogenesis. It also suppressed proliferation and induced substantial apoptosis in HCC cells. Remarkably, garcinol inhibited the growth of human HCC xenograft tumors in athymic nu/nu mice, through the inhibition of STAT3 activation. Conclusion Overall, our results suggest that garcinol exerts its anti-proliferative and pro-apoptotic effects through suppression of STAT3 signaling in HCC both in vitro and in vivo.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | - John M Luk
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore.
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Frank SB, Miranti CK. Disruption of prostate epithelial differentiation pathways and prostate cancer development. Front Oncol 2013; 3:273. [PMID: 24199173 PMCID: PMC3813973 DOI: 10.3389/fonc.2013.00273] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Accepted: 10/18/2013] [Indexed: 12/14/2022] Open
Abstract
One of the foremost problems in the prostate cancer (PCa) field is the inability to distinguish aggressive from indolent disease, which leads to difficult prognoses and thousands of unnecessary surgeries. This limitation stems from the fact that the mechanisms of tumorigenesis in the prostate are poorly understood. Some genetic alterations are commonly reported in prostate tumors, including upregulation of Myc, fusion of Ets genes to androgen-regulated promoters, and loss of Pten. However, the specific roles of these aberrations in tumor initiation and progression are poorly understood. Likewise, the cell of origin for PCa remains controversial and may be linked to the aggressive potential of the tumor. One important clue is that prostate tumors co-express basal and luminal protein markers that are restricted to their distinct cell types in normal tissue. Prostate epithelium contains layer-specific stem cells as well as rare bipotent cells, which can differentiate into basal or luminal cells. We hypothesize that the primary oncogenic cell of origin is a transient-differentiating bipotent cell. Such a cell must maintain tight temporal and spatial control of differentiation pathways, thus increasing its susceptibility for oncogenic disruption. In support of this hypothesis, many of the pathways known to be involved in prostate differentiation can be linked to genes commonly altered in PCa. In this article, we review what is known about important differentiation pathways (Myc, p38MAPK, Notch, PI3K/Pten) in the prostate and how their misregulation could lead to oncogenesis. Better understanding of normal differentiation will offer new insights into tumor initiation and may help explain the functional significance of common genetic alterations seen in PCa. Additionally, this understanding could lead to new methods for classifying prostate tumors based on their differentiation status and may aid in identifying more aggressive tumors.
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Affiliation(s)
- Sander B Frank
- Laboratory of Integrin Signaling and Tumorigenesis, Van Andel Research Institute , Grand Rapids, MI , USA ; Genetics Graduate Program, Michigan State University , East Lansing, MI , USA
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Rajendran P, Li F, Shanmugam MK, Kannaiyan R, Goh JN, Wong KF, Wang W, Khin E, Tergaonkar V, Kumar AP, Luk JM, Sethi G. Celastrol suppresses growth and induces apoptosis of human hepatocellular carcinoma through the modulation of STAT3/JAK2 signaling cascade in vitro and in vivo. Cancer Prev Res (Phila) 2012; 5:631-43. [PMID: 22369852 DOI: 10.1158/1940-6207.capr-11-0420] [Citation(s) in RCA: 124] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Cumulative evidences(s) have established that the constitutive activation of STAT3 plays a pivotal role in the proliferation, survival, metastasis, and angiogenesis and thus can contribute directly to the pathogenesis of hepatocellular carcinoma (HCC). Thus, novel agents that can inhibit STAT3 activation have potential for both prevention and treatment of HCCs. The effect of celastrol on STAT3 activation, associated protein kinases, STAT3-regulated gene products, cellular proliferation, and apoptosis was investigated. The in vivo effect of celastrol on the growth of human HCC xenograft tumors in athymic nu/nu mice was also examined. We observed that celastrol inhibited both constitutive and inducible STAT3 activation, and the suppression was mediated through the inhibition of activation of upstream kinases c-Src, as well as Janus-activated kinase-1 and -2. Vanadate treatment reversed the celastrol-induced modulation of STAT3, suggesting the involvement of a tyrosine phosphatase. The inhibition of STAT3 activation by celastrol led to the suppression of various gene products involved in proliferation, survival, and angiogenesis. Celastrol also inhibited the proliferation and induced apoptosis in HCC cells. Finally, when administered intraperitoneally, celastrol inhibited STAT3 activation in tumor tissues and the growth of human HCC xenograft tumors in athymic nu/nu mice without any side effects. Overall, our results suggest for the first time that celastrol exerts its antiproliferative and proapoptotic effects through suppression of STAT3 signaling in HCC both in vitro and in vivo.
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Affiliation(s)
- Peramaiyan Rajendran
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore
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Abstract
Cells from primary tumours need to go through several steps to become fully metastatic. During this process, cancer cells acquire the ability to invade, migrate across the surrounding tissue, enter into the circulation and colonize distant organs. In the present paper, we review recent progress in understanding how the p38 MAPK (mitogen-activated protein kinase) signalling pathway participates in the different steps of metastasis. Experimental evidence suggests that tumour cells need to modulate p38 MAPK activity levels to successfully metastasize.
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Wajner SM, Maia AL. New Insights toward the Acute Non-Thyroidal Illness Syndrome. Front Endocrinol (Lausanne) 2012; 3:8. [PMID: 22654851 PMCID: PMC3356062 DOI: 10.3389/fendo.2012.00008] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2011] [Accepted: 01/10/2012] [Indexed: 11/13/2022] Open
Abstract
The non-thyroidal illness syndrome (NTIS) refers to changes in serum thyroid hormone levels observed in critically ill patients in the absence of hypothalamic-pituitary-thyroid primary dysfunction. Affected individuals have low T3, elevated rT3, and inappropriately normal TSH levels. The pathophysiological mechanisms are poorly understood but the acute and chronic changes in pituitary-thyroid function are probably the consequence of the action of multiple factors. The early phase seems to reflect changes occurring primarily in the peripheral thyroid hormone metabolism, best seen in humans since 80-90% of the circulating T3 are derived from the pro-hormone T4. The conversion of T4 to T3 is catalyzed by type 1 (D1) and type 2 (D2) deiodinases via outer-ring deiodination. In contrast, type 3 deiodinase (D3) catalyzes the inactivation of both T4 and T3. Over the last decades, several studies have attempted to elucidate the mechanisms underlying the changes on circulating thyroid hormones in NTIS. Increased inflammatory cytokines, which occurs in response to virtually any illness, has long been speculated to play a role in derangements of deiodinase expression. On the other hand, oxidative stress due to augmented reactive oxygen species (ROS) generation is characteristic of many diseases that are associated with NTIS. Changes in the intracellular redox state may disrupt deiodinase function by independent mechanisms, which might include depletion of the as yet unidentified endogenous thiol cofactor. Here we aim to present an updated picture of the advances in understanding the mechanisms that result in the fall of thyroid hormone levels in the acute phase of NTIS.
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Affiliation(s)
- Simone Magagnin Wajner
- Thyroid Section, Endocrine Division, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do SulPorto Alegre, Brasil
| | - Ana Luiza Maia
- Thyroid Section, Endocrine Division, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do SulPorto Alegre, Brasil
- *Correspondence: Ana Luiza Maia, Serviço de Endocrinologia, Hospital de Clínicas de Porto Alegre, Rua Ramiro Barcelos, 2350, CEP 90035-003 Porto Alegre, Brasil. e-mail:
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Mir SA, Chatterjee A, Mitra A, Pathak K, Mahata SK, Sarkar S. Inhibition of signal transducer and activator of transcription 3 (STAT3) attenuates interleukin-6 (IL-6)-induced collagen synthesis and resultant hypertrophy in rat heart. J Biol Chem 2011; 287:2666-77. [PMID: 22157761 DOI: 10.1074/jbc.m111.246173] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
IL-6 has been shown to play a major role in collagen up-regulation process during cardiac hypertrophy, although the precise mechanism is still not known. In this study we have analyzed the mechanism by which IL-6 modulates cardiac hypertrophy. For the in vitro model, IL-6-treated cultured cardiac fibroblasts were used, whereas the in vivo cardiac hypertrophy model was generated by renal artery ligation in adult male Wistar rats (Rattus norvegicus). During induction of hypertrophy, increased phosphorylation of STAT1, STAT3, MAPK, and ERK proteins was observed both in vitro and in vivo. Treatment of fibroblasts with specific inhibitors for STAT1 (fludarabine, 50 μM), STAT3 (S31-201, 10 μM), p38 MAPK (SB203580, 10 μM), and ERK1/2 (U0126, 10 μM) resulted in down-regulation of IL-6-induced phosphorylation of specific proteins; however, only S31-201 and SB203580 inhibited collagen biosynthesis. In ligated rats in vivo, only STAT3 inhibitors resulted in significant decrease in collagen synthesis and hypertrophy markers such as atrial natriuretic factor and β-myosin heavy chain. In addition, decreased heart weight to body weight ratio and improved cardiac function as measured by echocardiography was evident in animals treated with STAT3 inhibitor or siRNA. Compared with IL-6 neutralization, more pronounced down-regulation of collagen synthesis and regression of hypertrophy was observed with STAT3 inhibition, suggesting that STAT3 is the major downstream signaling molecule and a potential therapeutic target for cardiac hypertrophy.
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Affiliation(s)
- Saiful Anam Mir
- Department of Zoology, University of Calcutta, 35, Ballygunge Circular Road, Kolkata 700 019, India
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Wajner SM, Goemann IM, Bueno AL, Larsen PR, Maia AL. IL-6 promotes nonthyroidal illness syndrome by blocking thyroxine activation while promoting thyroid hormone inactivation in human cells. J Clin Invest 2011; 121:1834-45. [PMID: 21540553 DOI: 10.1172/jci44678] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2010] [Accepted: 02/16/2011] [Indexed: 12/19/2022] Open
Abstract
Nonthyroidal illness syndrome (NTIS) is a state of low serum 3,5,3' triiodothyronine (T₃) that occurs in chronically ill patients; the degree of reduction in T₃ is associated with overall prognosis and survival. Iodthyronine deiodinases are enzymes that catalyze iodine removal from thyroid hormones; type I and II deiodinase (D1 and D2, respectively) convert the prohormone thyroxine T₄ to active T₃, whereas the type III enzyme (D3) inactivates T₄ and T₃. Increased production of cytokines, including IL-6, is a hallmark of the acute phase of NTIS, but the role of cytokines in altered thyroid hormone metabolism is poorly understood. Here, we measured the effect of IL-6 on both endogenous cofactor-mediated and dithiothreitol-stimulated (DTT-stimulated) cell sonicate deiodinase activities in human cell lines. Active T₃ generation by D1 and D2 in intact cells was suppressed by IL-6, despite an increase in sonicate deiodinases (and mRNAs). N-acetyl-cysteine (NAC), an antioxidant that restores intracellular glutathione (GSH) concentrations, prevented the IL-6-induced inhibitory effect on D1- and D2-mediated T₃ production, which suggests that IL-6 might function by depleting an intracellular thiol cofactor, perhaps GSH. In contrast, IL-6 stimulated endogenous D3-mediated inactivation of T₃. Taken together, these results identify a single pathway by which IL-6-induced oxidative stress can reduce D1- and D2-mediated T₄-to-T₃ conversion as well as increasing D3-mediated T₃ (and T₄) inactivation, thus mimicking events during illness.
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Affiliation(s)
- Simone Magagnin Wajner
- Thyroid Section, Endocrine Division, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
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Goodman WA, Young AB, McCormick TS, Cooper KD, Levine AD. Stat3 phosphorylation mediates resistance of primary human T cells to regulatory T cell suppression. THE JOURNAL OF IMMUNOLOGY 2011; 186:3336-45. [PMID: 21307288 DOI: 10.4049/jimmunol.1001455] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Human autoimmune diseases are characterized by systemic T cell dysfunction, resulting in chronically activated Th1 and Th17 cells that are inadequately suppressed by regulatory T cells (Tregs). IL-6, which is overexpressed in tissue and serum of patients with autoimmune diseases, inhibits human Treg function. We sought to determine the mechanism for the antitolerogenic properties of IL-6 by examining the signaling pathways downstream of IL-6R in primary human T cells. Inhibition of Stat3 signaling in MLCs containing IL-6 restores Treg-mediated suppression, demonstrating that IL-6-mediated loss of Treg suppression requires phosphorylation of Stat3. Cultures in which either effector T cells (Teffs) or Tregs were pretreated with Stat3 inhibitors indicate that phosphorylated (p)Stat3 is required in both T cell populations for IL-6-mediated reversal of Treg function. IL-21, which signals preferentially through pStat3, also reverses Treg suppression, in contrast to IL-27 and IFN-γ, which signal preferentially through Stat1 and do not inhibit Treg function. Interestingly, both Teffs and Tregs respond to IL-6 stimulation through strong Stat3 phosphorylation with minimal MAPK/Erk activation and moderate Stat1 phosphorylation. Finally, Teffs stimulated strongly through the TCR are also resistant to suppression by Tregs and show concurrent Stat3 phosphorylation. In these cultures, inhibition of pStat3 restores functional suppression by Tregs. Taken together, our findings suggest that an early dominance of Stat3 signaling, prior to subsequent T cell activation, is required for the loss of functional Treg suppression and that kinase-specific inhibitors may hold therapeutic promise in the treatment of autoimmune and chronic inflammatory diseases.
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Affiliation(s)
- Wendy A Goodman
- Department of Dermatology, Case Western Reserve University, University Hospitals Case Medical Center, Cleveland, OH 44106, USA.
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Liu Y, Brymora J, Zhang H, Smith B, Ramezani-Moghadam M, George J, Wang J. Leptin and acetaldehyde synergistically promotes αSMA expression in hepatic stellate cells by an interleukin 6-dependent mechanism. Alcohol Clin Exp Res 2011; 35:921-8. [PMID: 21294755 DOI: 10.1111/j.1530-0277.2010.01422.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND The mechanisms whereby patients with obesity/overweight are more susceptible to alcohol-associated liver fibrosis are unclear. Leptin, a peptide hormone secreted by white adipose tissue is increased in association with overweight/obesity and is recognized as mediator of liver fibrosis. We sought to assess whether leptin contributes to alcoholic liver fibrosis by in vitro studies in hepatic stellate cells (HSC). METHODS Rat HSCs in second or third passage were utilised. Leptin, Acetaldehyde or combination with leptin and acetaldehyde were incubated for specific periods in cultured HSCs. Profibrogenic gene and protein expression were determined and associated-signalling pathways were assessed. Interleukin 6 (IL-6) antibody neutralization was used to evaluate the role of IL-6. RESULTS Leptin did not promote acetaldehyde-induced gene expression of collagen I, transforming growth factor β1 (TGFβ1) and tissue inhibitor of metalloproteinase 1 (TIMP1) in vitro. However, combined treatment of leptin with acetaldehyde synergistically enhanced the protein expression of smooth muscle actin (αSMA), an activation marker of HSCs, and of Interleukin-6 (IL-6). The combination of leptin and acetaldehyde also augmented MAPK/p38 and MAPK/ERK1/2 phosphoprotein expression. IL-6 neutralization down-regulated protein expression of pp38, pERK1/2 and αSMA, while exogenous rat recombinant IL-6 administration up-regulated αSMA. Similarly, MAPK/p38 and MAPK/ERK1/2 inhibition attenuated αSMA expression. H(2)O(2) induction by acetaldehyde was not potentiated by co-treatment with leptin nor did IL-6 neutralization reduce acetaldehyde-induced H(2)O(2) production. CONCLUSIONS We conclude that leptin potentiates acetaldehyde-induced HSC activation and αSMA expression by an IL-6-dependent mechanism.
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Affiliation(s)
- Yingdi Liu
- Storr Liver Unit, Westmead Millennium Institute, University of Sydney and Westmead Hospital, Australia
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30
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Rajendran P, Ong TH, Chen L, Li F, Shanmugam MK, Vali S, Abbasi T, Kapoor S, Sharma A, Kumar AP, Hui KM, Sethi G. Suppression of signal transducer and activator of transcription 3 activation by butein inhibits growth of human hepatocellular carcinoma in vivo. Clin Cancer Res 2010; 17:1425-39. [PMID: 21131551 DOI: 10.1158/1078-0432.ccr-10-1123] [Citation(s) in RCA: 117] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
PURPOSE Hepatocellular carcinoma (HCC) is the fifth most common malignancy worldwide and the third cause of global cancer mortality. Increasing evidence suggest that STAT3 is a critical mediator of oncogenic signaling in HCC and controls the expression of several genes involved in proliferation, survival, metastasis, and angiogenesis. Thus, the novel agents that can suppress STAT3 activation have potential for both prevention and treatment of HCC. EXPERIMENTAL DESIGN The effect of butein on STAT3 activation, associated protein kinases, STAT3-regulated gene products, cellular proliferation, and apoptosis was investigated. The in vivo effect of butein on the growth of human HCC xenograft tumors in male athymic nu/nu mice was also examined. RESULTS We tested an agent, butein, for its ability to suppress STAT3 activation in HCC cells and nude mice model along with prospectively testing the hypothesis of STAT3 inhibition in a virtual predictive functional proteomics tumor pathway technology platform. We found that butein inhibited both constitutive and inducible STAT3 activation in HCC cells. The suppression was mediated through the inhibition of activation of upstream kinases c-Src and Janus-activated kinase 2. Butein inhibited proliferation and significantly potentiated the apoptotic effects of paclitaxel and doxorubicin in HCC cells. When administered intraperitoneally, butein inhibited the growth of human HCC xenograft tumors in male athymic nu/nu mice. CONCLUSIONS Overall, cumulative results from experimental and predictive studies suggest that butein exerts its antiproliferative and proapoptotic effects through suppression of STAT3 signaling in HCC both in vitro and in vivo.
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Affiliation(s)
- Peramaiyan Rajendran
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
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Ramadoss P, Chiappini F, Bilban M, Hollenberg AN. Regulation of hepatic six transmembrane epithelial antigen of prostate 4 (STEAP4) expression by STAT3 and CCAAT/enhancer-binding protein alpha. J Biol Chem 2010; 285:16453-66. [PMID: 20304921 DOI: 10.1074/jbc.m109.066936] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
STEAP4 is a plasma membrane metalloreductase involved in the transport of iron and copper. Recently, STEAP4 was implicated in promoting insulin sensitivity by acting in white adipose tissue to control the production of inflammatory cytokines such as interleukin 6. Indeed, the loss of STEAP4 expression in mice leads to increased production of inflammatory cytokines in visceral white adipose tissue and systemic insulin resistance. In this study, we demonstrate that in mouse liver STEAP4 is produced at significant levels and that steap4 transcription is induced by interleukin 6. We further demonstrate that the steap4 gene is a direct target of phosphorylated STAT3 in mouse liver. In addition, hepatic STEAP4 expression is regulated by feeding and fasting, and obesity leads to the induction of STEAP4 expression in the liver. Interestingly, the regulation of STEAP4 in both feeding and fasting and the obese state appears to require the transcription factor CCAAT/enhancer-binding protein alpha that may act in concert with STAT3 as they both bind to the proximal steap4 promoter in vivo. Taken together, these data suggest the transcriptional regulation of hepatic STEAP4 may play a critical role in the response to nutritional and inflammatory stress and contributes to the protective effect of STEAP4 in vivo.
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Affiliation(s)
- Preeti Ramadoss
- From the Division of Endocrinology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts 02215, USA
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Li F, Fernandez PP, Rajendran P, Hui KM, Sethi G. Diosgenin, a steroidal saponin, inhibits STAT3 signaling pathway leading to suppression of proliferation and chemosensitization of human hepatocellular carcinoma cells. Cancer Lett 2010; 292:197-207. [PMID: 20053498 DOI: 10.1016/j.canlet.2009.12.003] [Citation(s) in RCA: 137] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2009] [Revised: 12/07/2009] [Accepted: 12/07/2009] [Indexed: 11/18/2022]
Abstract
Constitutive activation of STAT3 has been shown in several human cancers and transformed cell lines including hepatocellular carcinoma (HCC). In the present report, we investigated whether diosgenin, a steroidal saponin isolated from fenugreek can modulate the STAT3 signaling pathway. We found that diosgenin inhibited both constitutive and inducible activation of STAT3 with no effect on STAT5. The activation of c-Src, JAK1 and JAK2 implicated in STAT3 activation, were also suppressed by this saponin. Pervanadate reversed the diosgenin-induced downregulation of STAT3, suggesting the involvement of a protein tyrosine phosphatase. Indeed, we found that diosgenin can induce the expression of Src homology 2 phosphatase 2 (SH-PTP2) that correlated with downregulation of constitutive STAT3 activation. Diosgenin also downregulated the expression of various STAT3-regulated gene products, inhibited proliferation and potentiated the apoptotic effects of paclitaxel and doxorubicin. Overall, these results suggest that diosgenin is a novel blocker of the STAT3 activation pathway, with a potential role in the treatment of HCC and other cancers.
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Affiliation(s)
- Feng Li
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, 117597, Singapore
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Pricola KL, Kuhn NZ, Haleem-Smith H, Song Y, Tuan RS. Interleukin-6 maintains bone marrow-derived mesenchymal stem cell stemness by an ERK1/2-dependent mechanism. J Cell Biochem 2009; 108:577-88. [PMID: 19650110 DOI: 10.1002/jcb.22289] [Citation(s) in RCA: 205] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Adult human mesenchymal stem cells (MSCs) hold promise for an increasing list of therapeutic uses due to their ease of isolation, expansion, and multi-lineage differentiation potential. To maximize the clinical potential of MSCs, the underlying mechanisms by which MSC functionality is controlled must be understood. We have taken a deconstructive approach to understand the individual components in vitro, namely the role of candidate "stemness" genes. Our recent microarray gene expression profiling data suggest that interleukin-6 (IL-6) may contribute to the maintenance of MSCs in their undifferentiated state. In this study, we showed that IL-6 gene expression is significantly higher in undifferentiated MSCs as compared to their chondrogenic, osteogenic, and adipogenic derivatives. Moreover, we found that MSCs secrete copious amounts of IL-6 protein, which decreases dramatically during osteogenic differentiation. We further evaluated the role of IL-6 for maintenance of MSC "stemness," using a series of functional assays. The data showed that IL-6 is both necessary and sufficient for enhanced MSC proliferation, protects MSCs from apoptosis, inhibits adipogenic and chondrogenic differentiation of MSCs, and increases the rate of in vitro wound healing of MSCs. We further identified ERK1/2 activation as the key pathway through which IL-6 regulates both MSC proliferation and inhibition of differentiation. Taken together, these findings show for the first time that IL-6 maintains the proliferative and undifferentiated state of bone marrow-derived MSCs, an important parameter for the optimization of both in vitro and in vivo manipulation of MSCs.
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Affiliation(s)
- Katie L Pricola
- Cartilage Biology and Orthopaedics Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland 20892, USA
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Garcia de Aquino S, Manzolli Leite FR, Stach-Machado DR, Francisco da Silva JA, Spolidorio LC, Rossa C. Signaling pathways associated with the expression of inflammatory mediators activated during the course of two models of experimental periodontitis. Life Sci 2009; 84:745-54. [PMID: 19285515 DOI: 10.1016/j.lfs.2009.03.001] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2008] [Revised: 02/19/2009] [Accepted: 03/01/2009] [Indexed: 10/21/2022]
Abstract
AIMS Evaluate the signaling pathways associated with inflammatory mediators activated in two models of experimental periodontitis. MAIN METHODS Two models were used: lipopolysaccharide (LPS) injections and ligature placement. Wistar rats were used and 30 microg LPS from Escherichia coli was injected twice a week into the palatal aspect of the upper molars. Ligatures were placed around lower first molars. A control group received injections of PBS on the palatal gingivae whereas no ligatures were placed on the lower molars. Samples were collected 5, 15 and 30 days and processed for analysis by Western blotting and stereometry. KEY FINDINGS The ligature model was associated with rapid and transient activation of extracellular-regulated kinases (ERK) and p38 mitogen-activated protein kinase (MAPK) as well as of nuclear factor kappa B (NF-kappaB). Activation of these signaling pathways on the LPS model was delayed but sustained throughout the 30-day experimental period. Inflammatory changes induced by both models were similar; however there was a significant reduction on inflammation degree on the ligature model, which paralleled the decrease observed on the activation of the signaling pathways. Activation of signal transducer and activator of transcription (STAT)-3 by phosphorylation of Tyrosine residues and of STAT-5 was observed only on the ligature model. SIGNIFICANCE Regulation of gene expression results from the activation of signaling pathways initiated by receptor-ligand binding of external antigens and also of cytokines produced by the host immune system. Understanding the signaling pathways relevant for a given condition may provide information useful for novel therapeutic approaches.
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Affiliation(s)
- Sabrina Garcia de Aquino
- Department of Diagnosis and Surgery, School of Dentistry at Araraquara, State University of Sao Paulo, Rua Humaita, 1680-Centro, Araraquara, SP 14801-903, Brazil
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Jiang CC, Lucas K, Avery-Kiejda KA, Wade M, deBock CE, Thorne RF, Allen J, Hersey P, Zhang XD. Up-regulation of Mcl-1 Is Critical for Survival of Human Melanoma Cells upon Endoplasmic Reticulum Stress. Cancer Res 2008; 68:6708-17. [DOI: 10.1158/0008-5472.can-08-0349] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Uddin MN, Horvat D, Glaser SS, Mitchell BM, Puschett JB. Examination of the cellular mechanisms by which marinobufagenin inhibits cytotrophoblast function. J Biol Chem 2008; 283:17946-53. [PMID: 18434301 DOI: 10.1074/jbc.m800958200] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Marinobufagenin (MBG) is an endogenous mammalian cardiotonic steroid involved in the inhibition of Na(+)/K(+)-ATPase. Increased plasma levels have been reported in patients with volume expansion-related hypertension. We have recently demonstrated that MBG impairs first trimester cytotrophoblast (CTB) cell proliferation, migration, and invasion, which may play a role in the development of preeclampsia. However, whether apoptosis contributes to altered CTB cell function by MBG remains unknown. Using the human extravillous CTB cell line SGHPL-4, we examined the effect of MBG and a similar Na(+)/K(+)-ATPase inhibitor, ouabain, on the phosphorylation status of Jnk, p38, and Src. Additionally, we measured apoptosis by caspase 9 and 3/7 activity and by annexin-V staining. We also investigated interleukin-6 (IL-6) secretion with or without p38 and Jnk inhibition. MBG significantly increased the phosphorylation of Jnk, p38, and Src and increased the expression of caspase 9 and 3/7 indicating the activation of apoptosis. MBG treatment also stimulated the expression of the early apoptosis marker, annexin-V, which was prevented by Jnk and p38 inhibition. MBG also stimulated the secretion of IL-6, which was attenuated by p38 inhibition. Ouabain had similar effects to those of MBG, suggesting that the apoptotic effects on CTB cells may be mediated by inhibition of Na(+)/K(+)-ATPase. In conclusion, the MBG-induced impairment of CTB function occurs via activation of Jnk, p38, and Src leading to increased apoptosis and IL-6 secretion. These observations may have clinical applicability with respect to the therapy of preeclampsia.
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Affiliation(s)
- Mohammad N Uddin
- Division of Nephrology and Hypertension, Department of Medicine, Texas A&M Health Science Center, Scott and White Clinic, Temple, TX 76508, USA
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Abstract
Hepatocellular carcinoma (HCC) is one of the most common cancers in the world. Studies indicate that the development of HCC is related to signal transduction of Ras-MAPK.P38MAPK, an important member of the family of mitogen-activated protein kinases. P38MAPK participates in cell proliferation, apoptosis and differentiation and plays a key role in cell apoptosis. P38MAPK is closely related with carcinogenesis, rapid generation and infinite growth of liver cancer and plays a role in the occurrence and development of liver cancer induced by organics, HBV and HCV. Drugs exert their anti-tumor effects through p38MAPK which also takes part in the formation of drug resistance to HCC. This paper reviews the advances in studies on p38MAPK-related HCC.
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Wada Y, Shimada K, Kimura T, Ushiyama S. Novel p38 MAP kinase inhibitor R-130823 suppresses IL-6, IL-8 and MMP-13 production in spheroid culture of human synovial sarcoma cell line SW 982. Immunol Lett 2008; 101:50-9. [PMID: 15888346 DOI: 10.1016/j.imlet.2005.04.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2005] [Accepted: 04/05/2005] [Indexed: 11/20/2022]
Abstract
Synovial hyperplasia is a hallmark of rheumatoid arthritis (RA) and is regarded as a major destructive element of articular bone and cartilage. This pathological process is accompanied by the production of proinflammatory cytokines, prostaglandin E(2) (PGE(2)), and matrix metalloproteinases (MMPs) in synoviocytes. We studied the spontaneous production of these substances in RA synoviocytes in spheroid culture. Synovial sarcoma cell line SW 982 formed a single spheroid in non-adherent culture plates. It produced interleukin (IL)-1beta, IL-6, IL-8, PGE(2), MMP-2 and MMP-13. Neither the addition of integrin antagonizing oligopeptide (GRGDSP) nor that of vitronectin receptor inhibitor SB-265123 to the culture inhibited any production. Phosphorylation of p38 mitogen-activated protein (MAP) kinase was observed during the culture. A novel p38 MAP kinase inhibitor, R-130823, inhibited the release of IL-6, IL-8 and MMP-13 in a concentration-dependent manner, but not that of IL-1beta or MMP-2. Real-time RT-PCR analysis demonstrated that IL-6, IL-8 and MMP-13 were inhibited at the transcriptional level. R-130823 did not affect the production of PGE(2) in spheroid culture, while the addition of R-130823 suppressed IL-1beta-induced PGE(2) synthesis in monolayer culture of SW 982 cells. The results suggest that spheroid culture induced proinflammatory factors and MMPs in signaling pathways both dependent and independent of p38 MAP kinase.
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Affiliation(s)
- Yoshihiro Wada
- Clinical Development Department, Sankyo Co., Ltd., 1-2-58, Hiromachi, Shinagawa-ku, Tokyo 140-8710, Japan.
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Kurdi M, Booz GW. Can the protective actions of JAK-STAT in the heart be exploited therapeutically? Parsing the regulation of interleukin-6-type cytokine signaling. J Cardiovasc Pharmacol 2007; 50:126-41. [PMID: 17703129 DOI: 10.1097/fjc.0b013e318068dd49] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Activation of the transcription factor signal transducers and activators of transcription (STAT) 3 is a defining feature of the interleukin (IL)-6 family of cytokines, which include IL-6, leukemia inhibitory factor, and cardiotrophin-1. These cytokines, as well as STAT3 activation, have been shown to be protective for cardiac myocytes and necessary for ischemia preconditioning. However, the mechanisms that regulate IL-6-type cytokine signaling in cardiac myocytes are largely unexplored. We propose that the protective character of IL-6-type cytokine signaling in cardiac myocytes is determined principally by three mechanisms: redox status of the nonreceptor tyrosine kinase Janus kinase 1 (JAK) 1 that activates STAT3, phosphorylation of STAT3 within the transcriptional activation domain on serine 727, and STAT3-mediated induction of suppressor of cytokine signaling (SOCS) 3 that terminates IL-6-type cytokine signaling. Moreover, we hypothesize that hyperactivation of the JAK kinases, particularly JAK2, mismatched STAT3 serine-tyrosine phosphorylation or heightened STAT3 transcriptional activity, and SOCS3 induction may ultimately prove detrimental. Here we summarize recent evidence that supports this hypothesis, as well as additional possible mechanisms of JAK-STAT regulation. Understanding how IL-6-type cytokine signaling is regulated in cardiac myocytes has great significance for exploiting the therapeutic potential of these cytokines and the phenomenon of preconditioning.
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Affiliation(s)
- Mazen Kurdi
- Division of Molecular Cardiology, Cardiovascular Research Institute, College of Medicine, The Texas A&M University System Health Science Center, College Station, TX 76504, USA
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Wang G, Qian P, Jackson FR, Qian G, Wu G. Sequential activation of JAKs, STATs and xanthine dehydrogenase/oxidase by hypoxia in lung microvascular endothelial cells. Int J Biochem Cell Biol 2007; 40:461-70. [PMID: 17920330 DOI: 10.1016/j.biocel.2007.08.008] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2007] [Revised: 07/30/2007] [Accepted: 08/21/2007] [Indexed: 01/19/2023]
Abstract
Xanthine dehydrogenase/oxidase (XDH/XO) is associated with various pathological conditions related to the endothelial injury. However, the molecular mechanism underlying the activation of XDH/XO by hypoxia remains largely unknown. In this report, we determined whether the Janus kinases (JAKs) and signal transducers and activators of transcription (STATs) signaling pathway is involved in hypoxia-induced activation of XDH/XO in primary cultures of lung microvascular endothelial cells (LMVEC). We found that hypoxia significantly increased interleukin 6 (IL6) production in a time-dependent manner in LMVEC. Hypoxia also markedly augmented phosphorylation/activation of JAKs (JAK1, JAK2 and JAK3) and the JAK downstream effectors STATs (STAT3 and STAT5). Hypoxia-induced activation of STAT3 was blocked by IL6 antibodies, the JAK inhibitor AG490 and the suppressor of cytokine signaling 3 (SOCS3), implying that hypoxia-promoted IL6 secretion activates the JAK/STAT pathway in LMVEC. Phosphorylation and DNA-binding activity of STAT3 were also inhibited by the p38 MAPK inhibitor SB203580 and the phosphatidylinositol 3-kinase inhibitor LY294002, suggesting that multiple signaling pathways involved in STAT activation by hypoxia. Importantly, hypoxia promoted XDH/XO activation in LMVEC, which was markedly reversed by inhibiting the JAK-STAT pathway using IL6 antibodies, AG490 and SOCS3. These data demonstrated that JAKs, STATs and XDH/XO were sequentially activated by hypoxia. These data provide the first evidence indicating that the JAK-STAT pathway is involved in hypoxia-mediated XDH/XO activation in LMVEC.
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Affiliation(s)
- Guansong Wang
- Institute of Respiratory Diseases, Xinqiao Hospital of Third Military Medical University, Chongqing 400037, PR China
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41
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Bioinformatics analysis of the early inflammatory response in a rat thermal injury model. BMC Bioinformatics 2007; 8:10. [PMID: 17214898 PMCID: PMC1797813 DOI: 10.1186/1471-2105-8-10] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2006] [Accepted: 01/10/2007] [Indexed: 12/25/2022] Open
Abstract
Background Thermal injury is among the most severe forms of trauma and its effects are both local and systemic. Response to thermal injury includes cellular protection mechanisms, inflammation, hypermetabolism, prolonged catabolism, organ dysfunction and immuno-suppression. It has been hypothesized that gene expression patterns in the liver will change with severe burns, thus reflecting the role the liver plays in the response to burn injury. Characterizing the molecular fingerprint (i.e., expression profile) of the inflammatory response resulting from burns may help elucidate the activated mechanisms and suggest new therapeutic intervention. In this paper we propose a novel integrated framework for analyzing time-series transcriptional data, with emphasis on the burn-induced response within the context of the rat animal model. Our analysis robustly identifies critical expression motifs, indicative of the dynamic evolution of the inflammatory response and we further propose a putative reconstruction of the associated transcription factor activities. Results Implementation of our algorithm on data obtained from an animal (rat) burn injury study identified 281 genes corresponding to 4 unique profiles. Enrichment evaluation upon both gene ontologies and transcription factors, verifies the inflammation-specific character of the selections and the rationalization of the burn-induced inflammatory response. Conducting the transcription network reconstruction and analysis, we have identified transcription factors, including AHR, Octamer Binding Proteins, Kruppel-like Factors, and cell cycle regulators as being highly important to an organism's response to burn response. These transcription factors are notable due to their roles in pathways that play a part in the gross physiological response to burn such as changes in the immune response and inflammation. Conclusion Our results indicate that our novel selection/classification algorithm has been successful in selecting out genes with play an important role in thermal injury. Additionally, we have demonstrated the value of an integrative approach in identifying possible points of intervention, namely the activation of certain transcription factors that govern the organism's response.
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Lim CP, Cao X. Structure, function, and regulation of STAT proteins. MOLECULAR BIOSYSTEMS 2006; 2:536-50. [PMID: 17216035 DOI: 10.1039/b606246f] [Citation(s) in RCA: 235] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The Signal Transducer and Activator of Transcription (STAT) family of proteins was first discovered in the 1990's as key proteins in cytokine signaling. Since then, the field has greatly advanced in the past 15 years, providing significant insight into the structure, function, and regulation of STATs. STATs are latent cytoplasmic transcription factors consisting of seven mammalian members. They are Tyr phosphorylated upon activation, a post-translational modification critical for dimerization, nuclear import, DNA binding, and transcriptional activation. In recent years, unphosphorylated STATs have also been observed to dimerize and drive transcription, albeit by yet an obscure mechanism. In addition, the function of cytoplasmic STATs is beginning to emerge. Here, we describe the structure, function, and regulation of both unphosphorylated and phosphorylated STATs. STAT isoforms from alternative splicing or proteolytic processing, and post-translational modifications affecting STAT activities are also discussed.
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Affiliation(s)
- Cheh Peng Lim
- Signal Transduction Laboratory, Institute of Molecular and Cell Biology, Singapore, 138673, Republic of Singapore
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Cohen M, Marchand-Adam S, Lecon-Malas V, Marchal-Somme J, Boutten A, Durand G, Crestani B, Dehoux M. HGF synthesis in human lung fibroblasts is regulated by oncostatin M. Am J Physiol Lung Cell Mol Physiol 2006; 290:L1097-103. [PMID: 16684952 DOI: 10.1152/ajplung.00166.2005] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Oncostatin M (OSM) is a IL-6 family cytokine locally produced in acute lung injury. Its profibrotic properties suggest a role in lung wound repair. Hepatocyte growth factor (HGF), produced by fibroblasts, is involved in pulmonary epithelial repair. We investigated the role of OSM in HGF synthesis by human lung fibroblasts. We showed that OSM upregulated HGF mRNA in MRC5 cells and in human lung fibroblasts, whereas IL-6 and leukemia inhibitory factor did not. OSM induced HGF secretion to a similar extent as IL-1beta in both a time- and dose-dependent manner. HGF was released in its cleaved mature form, and its secretion was completely inhibited in the presence of cycloheximide, indicating a de novo protein synthesis. OSM in combination with prostaglandin E(2), a powerful HGF inductor, led to an additive effect. OSM and indomethacin in combination further increased HGF secretion. This could be explained, at least in part, by a moderate upregulation of specific OSM receptor beta mRNA expression through cyclooxygenase inhibition. These results demonstrate that OSM-induced HGF synthesis did not involve a PGE(2) pathway. OSM-induced HGF secretion was inhibited by PD-98059 (a specific pharmacological inhibitor of ERK1/2), SB-203580 (a p38 MAPK inhibitor), and SP-600125 (a JNK inhibitor) by 70, 82, and 100%, respectively, whereas basal HGF secretion was only inhibited by SP-600125 by 30%. Our results demonstrate a specific upregulation of HGF synthesis by OSM, most likely through a MAPK pathway, and support the suggestion that OSM may participate in lung repair through HGF production.
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Affiliation(s)
- Murielle Cohen
- Service de Biochimie A, Hôpital Bichat-Claude Bernard, Assistance Publique-Hôpitaux de Paris, 46 rue Henri Huchard, 75877 Paris cedex 18, France
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Zauberman A, Cohen S, Mamroud E, Flashner Y, Tidhar A, Ber R, Elhanany E, Shafferman A, Velan B. Interaction of Yersinia pestis with macrophages: limitations in YopJ-dependent apoptosis. Infect Immun 2006; 74:3239-50. [PMID: 16714551 PMCID: PMC1479247 DOI: 10.1128/iai.00097-06] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The enteropathogenic Yersinia strains are known to downregulate signaling pathways in macrophages by effectors of the type III secretion system, in which YopJ/YopP plays a crucial role. The adverse effects of Yersinia pestis, the causative agent of plague, were examined by infecting J774A.1 cells, RAW264.7 cells, and primary murine macrophages with the EV76 strain and with the fully virulent Kimberley53 strain. Y. pestis exerts YopJ-dependent suppression of tumor necrosis factor alpha secretion and phosphorylation of mitogen-activated protein kinases and thus resembles enteropathogenic Yersinia. However, Y. pestis is less able to activate caspases, to suppress NF-kappaB activation, and to induce apoptosis in macrophages than the high-virulence Y. enterocolitica WA O:8 strain. These differences appear to be related to lower efficiency of YopJ effector translocation by Y. pestis. The efficiencies of effector translocation and of apoptosis induction can be enhanced either by using a high bacterial load in a synchronized infection or by overexpressing exogenous YopJ in Y. pestis. Replacing YopJ with the homologous Y. enterocolitica effector YopP can further enhance these effects. Overexpression of YopP in a yopJ-deleted Y. pestis background leads to rapid and effective translocation into target cells, providing Y. pestis with the high cytotoxic potential of Y. enterocolitica WA O:8. We suggest that the relative inferiority of Y. pestis in triggering cell death in macrophages may be advantageous for its in vivo propagation in the early stages of infection.
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Affiliation(s)
- Ayelet Zauberman
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, P.O. Box 19, Ness-Ziona, 74100, Israel
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Westra J, Bijzet J, Doornbos-van der Meer B, van Rijswijk MH, Limburg PC. Differential influence of p38 mitogen activated protein kinase (MAPK) inhibition on acute phase protein synthesis in human hepatoma cell lines. Ann Rheum Dis 2005; 65:929-35. [PMID: 16269426 PMCID: PMC1798216 DOI: 10.1136/ard.2005.043232] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND Inhibition of intracellular signal transduction is considered to be an interesting target for treatment in inflammation. p38 MAPK inhibitors, especially, have been developed and are now in phase II clinical trials for rheumatoid arthritis (RA). OBJECTIVE To investigate the influence of p38 MAPK inhibition on acute phase protein (APP) production, which is dependent on both JAK/STAT and p38 MAPK pathways. METHODS The effects of p38 MAPK inhibition on APP production and mRNA expression in four human hepatoma cell lines was investigated, after stimulation with interleukin (IL)6 and/or IL1beta or tumour necrosis factor alpha. RESULTS Two out of four cell lines produced C reactive protein (CRP), especially after combined IL6 and IL1beta stimulation. CRP production was significantly inhibited by the p38 MAPK specific inhibitor RWJ 67657 at 1 micromol/l, which is pharmacologically relevant. Fibrinogen production was also inhibited at 1 micromol/l in all cell lines. Serum amyloid A (SAA) was produced in all four lines. In contrast with CRP, SAA production was not inhibited by RWJ 67657 at 1 micromol/l. CONCLUSION Production and mRNA expression of CRP and fibrinogen, but not SAA production and mRNA expression, were significantly inhibited by p38 MAPK specific inhibitor in hepatoma cell lines. For p38 MAPK inhibitor treatment in RA SAA might be a better marker of disease activity than CRP and fibrinogen, because SAA is not directly affected by p38 MAPK inhibition.
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Affiliation(s)
- J Westra
- Department of Rheumatology, University Medical Centre Groningen, PO Box 30.001, 9700 RB Groningen, The Netherlands.
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46
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Lewis SM, Holcik M. IRES in distress: translational regulation of the inhibitor of apoptosis proteins XIAP and HIAP2 during cell stress. Cell Death Differ 2005; 12:547-53. [PMID: 15818406 DOI: 10.1038/sj.cdd.4401602] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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47
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Chang KT, Tsai CM, Chiou YC, Chiu CH, Jeng KS, Huang CYF. IL-6 induces neuroendocrine dedifferentiation and cell proliferation in non-small cell lung cancer cells. Am J Physiol Lung Cell Mol Physiol 2005; 289:L446-53. [PMID: 15894558 DOI: 10.1152/ajplung.00089.2005] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Interleukin-6 (IL-6) has been identified as an important growth regulator of lung cancer cells. Elevation of serum levels of IL-6 has been found in a subpopulation of lung cancer patients, but rarely in patients with benign lung diseases. Approximately 15% of non-small cell lung cancer (NSCLC) tumors exhibit neuroendocrine (NE) properties (NSCLC-NE) and have been suggested to have the biological characteristics similar to small cell lung cancer (SCLC) with early metastasis and initial responsiveness to chemotherapy. We recently showed that IL-6 promotes cell proliferation and downregulates the expression of neuron-specific enolase (NSE, one of the major NE markers) in NSCLC-NE cells. In this study, we show that IL-6 stimulates a transient increase of tyrosine phosphorylation of STAT3 in a dose-dependent fashion. Inhibition of STAT3 signaling pathway by either AG-490 (JAK2-specific inhibitor) or overexpression of STAT3Y705F (a dominant-negative STAT3) reverses NSE expression in IL-6- treated NSCLC-NE cells. In addition, IL-6 induces phosphorylation and activation of p38 MAPK. SB-203580, a p38 MAPK-specific inhibitor, inhibits IL-6-induced p38 MAPK phosphorylating activity and suppresses IL-6-stimulated cell proliferation. Together, our results indicate that STAT3 signaling pathway is involved in IL-6-induced NE differentiation and that p38 MAPK is associated with IL-6-stimulated growth regulation in NSCLC-NE cells. These data suggest that both kinase pathways play critical roles in the pathogenesis of NSCLC-NE malignancies, providing new molecular targets for future therapeutic approaches.
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Affiliation(s)
- Kuo-Ting Chang
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
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Loeffler S, Fayard B, Weis J, Weissenberger J. Interleukin-6 induces transcriptional activation of vascular endothelial growth factor (VEGF) in astrocytes in vivo and regulates VEGF promoter activity in glioblastoma cells via direct interaction between STAT3 and Sp1. Int J Cancer 2005; 115:202-13. [PMID: 15688401 DOI: 10.1002/ijc.20871] [Citation(s) in RCA: 165] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Interleukin-6 (IL-6) expression is strongly correlated with the degree of human glioma malignancy and necessary for tumor formation in a mouse model of spontaneous astrocytomas. Yet, exactly how IL-6 contributes to malignant progression of these brain tumors is still unclear. We have scrutinized the mechanism of transcriptional activation of vascular endothelial growth factor (VEGF) expression by IL-6 in the mouse brain and in glioblastoma cells. We demonstrate here that IL-6 drives transcriptional upregulation of VEGF in astrocytes in vivo using glial fibrillary acidic protein (GFAP)-IL-6/VEGF-green fluorescent protein (GFP) double transgenic mice. We further show that IL-6-induced VEGF transcription and VEGF secretion by human glioblastoma cells is dependent on signal transducer and activator of transcription 3 (STAT3). By progressive 5'-deletion analysis we defined the minimal VEGF promoter region for IL-6-responsiveness to nucleotides -88/-50. Surprisingly, this promoter region is rich in GC-boxes and does not contain STAT3 binding elements. Electrophoretic mobility shift and supershift assays revealed binding of Sp1 and Sp3 to the -88/-50 element upon IL-6 stimulation. Interestingly, preincubation with STAT3 antibody prevented the binding of Sp1 and Sp3 to the -88/-50 element, indicating that STAT3 is involved in IL-6-driven Sp1/Sp3 protein-DNA complex formation. Physical interaction of STAT3 and Sp1 was demonstrated by coimmunoprecipitation. The functional relevance of the STAT3/Sp1 association was corroborated by transient transfection experiments, which showed that overexpression of constitutively active STAT3 increased the minimal VEGF promoter activity. Taken together, our study suggests that IL-6 promotes tumor angiogenesis in gliomas and describes a novel transcriptional activation mechanism for STAT3 in the context of a STAT3 binding element (SBE)-free promoter.
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Affiliation(s)
- Sébastien Loeffler
- Division of Neuropathology, Institute of Pathology, University of Bern, Bern, Switzerland
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Komyod W, Bauer UM, Heinrich PC, Haan S, Behrmann I. Are STATS arginine-methylated? J Biol Chem 2005; 280:21700-5. [PMID: 15826948 DOI: 10.1074/jbc.c400606200] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Transcription factors of the STAT (signal transducer and activator of transcription) family are important in signal transduction of cytokines. They are subject to post-translational modification by phosphorylation on tyrosine and serine residues. Recent evidence suggested that STATs are methylated on a conserved arginine residue within the N-terminal region. STAT arginine methylation has been described to be important for STAT function and loss of arginine methylation was discussed to be involved in interferon resistance of cancer cells. Here we provide several independent lines of evidence indicating that the issue of arginine methylation of STATs has to be reassessed. First, we show that treatment of melanoma and fibrosarcoma cells with inhibitors used to suppress methylation (N-methyl-2-deoxyadenosine, adenosine, dl-homocysteine) had profound and rapid effects on phosphorylation of STAT1 and STAT3 but also on p38 and Erk signaling cascades which are known to cross-talk with the Jak/STAT pathway. Second, we show that anti-methylarginine antibodies did not precipitate specifically STAT1 or STAT3. Third, we show that mutation of Arg(31) to Lys led to destabilization of STAT1 and STAT3, implicating an important structural role of Arg(31). Finally, purified catalytically active protein arginine methyltransferases (PRMT1, -2, -3, -4, and -6) did not methylate STAT proteins, and cotransfection with PRMT1 did not affect STAT1-controlled reporter gene activity. Taken together, our data suggest the absence of arginine methylation of STAT1 and STAT3.
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Affiliation(s)
- Waraporn Komyod
- Institut für Biochemie, Universitätsklinikum der Rheinisch-Westfälischen Technischen Hochschule Aachen, Pauwelsstrasse 30, 52074 Aachen, Germany
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Veljkovic J, Hansen U. Lineage-specific and ubiquitous biological roles of the mammalian transcription factor LSF. Gene 2005; 343:23-40. [PMID: 15563829 PMCID: PMC3402097 DOI: 10.1016/j.gene.2004.08.010] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2004] [Revised: 07/30/2004] [Accepted: 08/12/2004] [Indexed: 01/15/2023]
Abstract
Transcriptional regulation in mammalian cells is driven by a complex interplay of multiple transcription factors that respond to signals from either external or internal stimuli. A single transcription factor can control expression of distinct sets of target genes, dependent on its state of post-translational modifications, interacting partner proteins, and the chromatin environment of the cellular genome. Furthermore, many transcription factors can act as either transcriptional repressors or activators, depending on promoter and cellular contexts [Alvarez, M., Rhodes, S.J., Bidwell, J.P., 2003. Context-dependent transcription: all politics is local. Gene 313, 43-57]. Even in this light, the versatility of LSF (Late SV40 Factor) is remarkable. A hallmark of LSF is its unusual DNA binding domain, as evidenced both by lack of homology to any other established DNA-binding domains and by its DNA recognition sequence. Although a dimer in solution, LSF requires additional multimerization with itself or partner proteins in order to interact with DNA. Transcriptionally, LSF can function as an activator or a repressor. It is a direct target of an increasing number of signal transduction pathways. Biologically, LSF plays roles in cell cycle progression and cell survival, as well as in cell lineage-specific functions, shown most strikingly to date in hematopoietic lineages. This review discusses how the unique aspects of LSF DNA-binding activity may make it particularly susceptible to regulation by signal transduction pathways and may relate to its distinct biological roles. We present current progress in elucidation of both tissue-specific and more universal cellular roles of LSF. Finally, we discuss suggestive data linking LSF to signaling by the amyloid precursor protein and to Alzheimer's disease, as well as to the regulation of latency of the human immunodeficiency virus (HIV).
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Affiliation(s)
| | - Ulla Hansen
- Corresponding author: Dept. Biology, Boston University, 5 Cummington Street, Boston, MA 02215; Tel.: (617) 353-8730; fax: (617) 353-8484;
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