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Wang Y, Pan L. Knockdown of CXCL3-inhibited apoptosis and inflammation in lipopolysaccharide-treated BEAS-2B and HPAEC through inactivating MAPKs pathway. Allergol Immunopathol (Madr) 2022; 50:10-6. [PMID: 35789398 DOI: 10.15586/aei.v50i4.621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Accepted: 03/22/2022] [Indexed: 11/18/2022]
Abstract
BACKGROUND CXCL3 (C-X-C motif chemokine ligand 3) is a member of chemokines family, which binds to the receptor to recruit neutrophils to lungs, thus participating in the pathogenesis of asthmatic lung. The role of CXCL3 in sepsis-induced acute lung injury is investigated here. METHODS Human lung epithelial cell line (BEAS-2B) and human pulmonary artery endothelial cell line (HPAEC) were treated with lipopolysaccharides (LPS). MTT and flow cytometry were performed to detect cell viability and apoptosis, respectively. Enzyme-linked immunosorbent assay (ELISA) and real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) were used to assess the levels of inflammatory factors. RESULTS Treatment with LPS resulted in the decrease of cell viability in BEAS-2B and HPAEC. CXCL3 was particularly upregulated in LPS-treated BEAS-2B and HPAE cells. Knockdown of CXCL3 enhanced viability and suppressed apoptosis i006E LPS-treated BEAS-2B and HPAE cells. Knockdown of CXCL3 also upregulated TNF-α, IL-1β, and IL-18 in LPS-treated BEAS-2B and HPAE cells. Moreover, knockdown of CXCL3 suppressed the activation of mitogen-activated protein kinases (MAPKs) signaling in LPS-treated BEAS-2B and HPAE cells through downregulation of p-ERK1/2, p-p38, and p-JNK. On the other hand, overexpression of CXCL3 caused completely opposite results in LPS-treated BEAS-2B and HPAE cells. CONCLUSION Knockdown of CXCL3 exerted antiapoptotic and anti-inflammatory effects against LPS-treated BEAS-2B and HPAE cells, at least partially, through inactivation of MAPKs signaling, suggesting a potential strategy for the intervention of sepsis-induced acute lung injury.
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Lu L, Cao L, Liu Y, Chen Y, Fan J, Yin Y. Angiotensin (ang) 1-7 inhibits ang II-induced atrial fibrosis through regulating the interaction of proto-oncogene tyrosine-protein kinase Src (c-Src) and Src homology region 2 domain-containing phosphatase-1 (SHP-1)). Bioengineered 2021; 12:10823-10836. [PMID: 34872449 PMCID: PMC8809921 DOI: 10.1080/21655979.2021.1967035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
To verify whether Ang-(1-7) produces an antagonistic effect on Ang II-mediated atrial remodeling. Ang II–induced HL-1 cell model and a rat model of Ang II–induced atrial remodeling were constructed and intervened with Ang II Ang-(1-7), AngII +Ang-(1-7), Ang II+ c-Src specific inhibitor (SU6656), and Ang II + Ang-(1-7) + SSG (SHP-1/2 specific inhibitor, stibogluconate), respectively. The systolic blood pressure of the rat caudal artery was detected. And trial fibrosis was detected by Picrosirius red staining and Masson’s trichrome staining. Expressions of transforming growth factor-β (TGF-β), tissue inhibitor of metalloproteinases 1 (TIMP1), Matrix metalloproteinase 2 (MMP-2), connective tissue growth factor (CTGF), galectin-3, α-smooth muscle actin (α-SMA), and collagen I/III were subjected to qPCR and western blot. Furthermore, SHP-1 binding to c-Src was verified by co-immunoprecipitation (Co-IP). Results showed that the expressions of TGF-β, TIMP1, MMP-2, CTGF, α-SMA, galectin-3, and collagen I were increased markedly in the Ang II intervention group, and the expressions of p-ERK1/2, p-Akt, and p-p38MAPK were also increased dramatically. Ang-(1-7) or SU6656 addition could inhibit the action of Ang II factor, thereby minimizing the expressions of the previously described genes and proteins. Simultaneously, SSG supplement reversed the antagonistic effect of Ang-(1-7) on Ang II, and the latter elevated the blood pressure and induced atrial fibrosis in rats. Ang-(1-7) could reverse the changes related to Ang II–induced atrial fibrosis in rats. In conclusion, Ang-(1-7) antagonized Ang II–induced atrial remodeling by regulating SHP-1 and c-Src, thereby affecting the MAPKs/Akt signaling pathway.
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Affiliation(s)
- Li Lu
- Department of Critical Care Medicine, University-Town Hospital of Chongqing Medical University, Chongqing, China
| | - Li Cao
- Department of Cardiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yihao Liu
- Department of Cardiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yunlin Chen
- Department of Cardiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Jinqi Fan
- Department of Cardiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yuehui Yin
- Department of Cardiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
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Das S, Nair RS, Mishra R, Sondarva G, Viswakarma N, Abdelkarim H, Gaponenko V, Rana B, Rana A. Mixed lineage kinase 3 promotes breast tumorigenesis via phosphorylation and activation of p21-activated kinase 1. Oncogene 2019; 38:3569-3584. [PMID: 30664689 PMCID: PMC7568686 DOI: 10.1038/s41388-019-0690-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Revised: 11/28/2018] [Accepted: 12/07/2018] [Indexed: 02/03/2023]
Abstract
Mixed lineage kinase 3 (MLK3), a MAP3K member has been envisioned as a viable drug target in cancer, yet its detailed function and signaling is not fully elucidated. We identified that MLK3 tightly associates with an oncogene, PAK1. Mammalian PAK1 being a Ste20 (MAP4K) member, we tested whether it is an upstream regulator of MLK3. In contrast to our hypothesis, MLK3 activated PAK1 kinase activity directly, as well as in the cells. Although, MLK3 can phosphorylate PAK1 on Ser133 and Ser204 sites, PAK1S133A mutant is constitutively active, whereas, PAK1S204A is not activated by MLK3. Stable overexpression of PAK1S204A in breast cancer cells, impedes migration, invasion, and NFĸB activity. In vivo breast cancer cell tumorigenesis is significantly reduced in tumors expressing PAK1S204A mutant. These results suggest that mammalian PAK1 does not act as a MAP4K and MLK3-induced direct activation of PAK1 plays a key role in breast cancer tumorigenesis.
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Affiliation(s)
- Subhasis Das
- Department of Surgery, Division of Surgical Oncology, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Rakesh Sathish Nair
- Department of Surgery, Division of Surgical Oncology, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Rajakishore Mishra
- Center for Life Sciences, School of Natural Sciences, Central University of Jharkhand, Ranchi, Jharkhand, 835205, India
| | - Gautam Sondarva
- Department of Surgery, Division of Surgical Oncology, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Navin Viswakarma
- Department of Surgery, Division of Surgical Oncology, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Hazem Abdelkarim
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, IL, 60607, USA
| | - Vadim Gaponenko
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, IL, 60607, USA
| | - Basabi Rana
- Department of Surgery, Division of Surgical Oncology, University of Illinois at Chicago, Chicago, IL, 60612, USA
- University of Illinois Hospital &Health Sciences System Cancer Center, University of Illinois at Chicago, Chicago, IL, 60612, USA
- Jesse Brown VA Medical Center, Chicago, IL, 60612, USA
| | - Ajay Rana
- Department of Surgery, Division of Surgical Oncology, University of Illinois at Chicago, Chicago, IL, 60612, USA.
- University of Illinois Hospital &Health Sciences System Cancer Center, University of Illinois at Chicago, Chicago, IL, 60612, USA.
- Jesse Brown VA Medical Center, Chicago, IL, 60612, USA.
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Abstract
OBJECTIVE To investigate the molecular mechanism by which salidroside protects PC12 cells from H2O2-induced apoptosis. METHODS PC12 cells cultured in DMEM supplemented with 10% horse serum and 5% fetal bovine serum were pretreated with different doses of salidroside for 2 h and then stimulated with H2O2 for different lengths of time. The expression levels of PARP and caspase 3 and the phosphorylation of p38, ERK and JNK were determined with Western blotting. The cell nuclear morphology was observed after DAPI staining. The production of ROS was detected using a ROS detection kit, and the levels of gp91phox and p47phox in the membrane and cytoplasm were detected by membrane-cytoplasm separation experiment; the binding between gp91phox and p47phox was assayed by coimmunoprecipitation experiment. RESULTS Salidroside dose-dependently suppressed cell apoptosis, lowered phosphorylation levels of p38, ERK and JNK, inhibited the production of ROS, reduced the binding between gp91phox and p47phox, and inhibited the activity of NOX2 in PC12 cells exposed to H2O2. CONCLUSION Salidroside protects PC12 cells from H2O2-induced apoptosis at least partly by suppressing NOX2-ROS-MAPKs signaling pathway.
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Baranova IN, Souza ACP, Bocharov AV, Vishnyakova TG, Hu X, Vaisman BL, Amar MJ, Chen Z, Kost Y, Remaley AT, Patterson AP, Yuen PST, Star RA, Eggerman TL. Human SR-BI and SR-BII Potentiate Lipopolysaccharide-Induced Inflammation and Acute Liver and Kidney Injury in Mice. J Immunol 2016; 196:3135-47. [PMID: 26936883 PMCID: PMC4856165 DOI: 10.4049/jimmunol.1501709] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 01/24/2016] [Indexed: 12/18/2022]
Abstract
The class B scavenger receptors BI (SR-BI) and BII (SR-BII) are high-density lipoprotein receptors that recognize various pathogens, including bacteria and their products. It has been reported that SR-BI/II null mice are more sensitive than normal mice to endotoxin-induced inflammation and sepsis. Because the SR-BI/II knockout model demonstrates multiple immune and metabolic disorders, we investigated the role of each receptor in the LPS-induced inflammatory response and tissue damage using transgenic mice with pLiv-11-directed expression of human SR-BI (hSR-BI) or human SR-BII (hSR-BII). At 6 h after i.p. LPS injection, transgenic hSR-BI and hSR-BII mice demonstrated markedly higher serum levels of proinflammatory cytokines and 2- to 3-fold increased expression levels of inflammatory mediators in the liver and kidney, compared with wild-type (WT) mice. LPS-stimulated inducible NO synthase expression was 3- to 6-fold higher in the liver and kidney of both transgenic strains, although serum NO levels were similar in all mice. Despite the lower high-density lipoprotein plasma levels, both transgenic strains responded to LPS by a 5-fold increase of plasma corticosterone levels, which were only moderately lower than in WT animals. LPS treatment resulted in MAPK activation in tissues of all mice; however, the strongest response was detected for hepatic extracellular signal-regulated protein kinase 1 and 2 and kidney JNK of both transgenic mice. Histological examination of hepatic and renal tissue from LPS-challenged mice revealed more injury in hSR-BII, but not hSR-BI, transgenic mice versus WT controls. Our findings demonstrate that hSR-BII, and to a lesser extent hSR-BI, significantly increase LPS-induced inflammation and contribute to LPS-induced tissue injury in the liver and kidney, two major organs susceptible to LPS toxicity.
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Affiliation(s)
- Irina N Baranova
- Department of Laboratory Medicine, Clinical Center, National Institutes of Health, Bethesda, MD 20892
| | - Ana C P Souza
- Renal Diagnostics and Therapeutics Unit, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Alexander V Bocharov
- Department of Laboratory Medicine, Clinical Center, National Institutes of Health, Bethesda, MD 20892;
| | - Tatyana G Vishnyakova
- Department of Laboratory Medicine, Clinical Center, National Institutes of Health, Bethesda, MD 20892
| | - Xuzhen Hu
- Renal Diagnostics and Therapeutics Unit, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Boris L Vaisman
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892; and
| | - Marcelo J Amar
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892; and
| | - Zhigang Chen
- Department of Laboratory Medicine, Clinical Center, National Institutes of Health, Bethesda, MD 20892
| | - Yana Kost
- Department of Laboratory Medicine, Clinical Center, National Institutes of Health, Bethesda, MD 20892
| | - Alan T Remaley
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892; and
| | - Amy P Patterson
- Department of Laboratory Medicine, Clinical Center, National Institutes of Health, Bethesda, MD 20892; National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892; and
| | - Peter S T Yuen
- Renal Diagnostics and Therapeutics Unit, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Robert A Star
- Renal Diagnostics and Therapeutics Unit, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Thomas L Eggerman
- Department of Laboratory Medicine, Clinical Center, National Institutes of Health, Bethesda, MD 20892; Division of Diabetes, Endocrinology, and Metabolic Diseases, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
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Vuong T, Mallet JF, Ouzounova M, Rahbar S, Hernandez-Vargas H, Herceg Z, Matar C. Role of a polyphenol-enriched preparation on chemoprevention of mammary carcinoma through cancer stem cells and inflammatory pathways modulation. J Transl Med 2016; 14:13. [PMID: 26762586 PMCID: PMC4712588 DOI: 10.1186/s12967-016-0770-7] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 12/21/2015] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Naturally occurring polyphenolic compounds from fruits, particularly from blueberries, have been reported to be significantly involved in cancer chemoprevention and chemotherapy. Biotransformation of blueberry juice by Serratia vaccinii increases its polyphenolic content and endows it with anti-inflammatory properties. METHODS This study evaluated the effect of a polyphenol-enriched blueberry preparation (PEBP) and its non-fermented counterpart (NBJ), on mammary cancer stem cell (CSC) development in in vitro, in vivo and ex vivo settings. Effects of PEBP on cell proliferation, mobility, invasion, and mammosphere formation were measured in vitro in three cell lines: murine 4T1 and human MCF7 and MDA-MB-231. Ex vivo mammosphere formation, tumor growth and metastasis observations were carried out in a BALB/c mouse model. RESULTS Our research revealed that PEBP influence cellular signaling cascades of breast CSCs, regulating the activity of transcription factors and, consequently, inhibiting tumor growth in vivo by decreasing metastasis and controlling PI3K/AKT, MAPK/ERK, and STAT3 pathways, central nodes in CSC inflammatory signaling. PEBP significantly inhibited cell proliferation of 4T1, MCF-7 and MDA-MB-231. In all cell lines, PEBP reduced mammosphere formation, cell mobility and cell migration. In vivo, PEBP significantly reduced tumor development, inhibited the formation of ex vivo mammospheres, and significantly reduced lung metastasis. CONCLUSIONS This study showed that polyphenol enrichment of a blueberry preparation by fermentation increases its chemopreventive potential by protecting mice against tumor development, inhibiting the formation of cancer stem cells and reducing lung metastasis. Thus, PEBP may represent a novel complementary alternative medicine therapy and a source for novel therapeutic agents against breast cancer.
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Affiliation(s)
- Tri Vuong
- Nutritional Sciences Program, Faculty of Health Sciences, University of Ottawa, R2057 Roger Guindon Hall, 451 Smyth Road, Ottawa, ON, K1H 8M5, Canada.
| | - Jean-François Mallet
- Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Canada.
| | - Maria Ouzounova
- Cancer Center, Georgia Regents University, Augusta, GA, USA.
| | - Sam Rahbar
- Nutritional Sciences Program, Faculty of Health Sciences, University of Ottawa, R2057 Roger Guindon Hall, 451 Smyth Road, Ottawa, ON, K1H 8M5, Canada.
| | | | - Zdenko Herceg
- International Agency for Research on Cancer, Lyon, France.
| | - Chantal Matar
- Nutritional Sciences Program, Faculty of Health Sciences, University of Ottawa, R2057 Roger Guindon Hall, 451 Smyth Road, Ottawa, ON, K1H 8M5, Canada.
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Choi JM, Choi YH, Kim SK, Ahn KH, Won JH, Lim JH, Jang YJ, Lee S, Kim DH, Kim DK. (S)-tetrahydroisoquinoline alkaloid inhibits LPS-induced arachidonic acid release through downregulation of cPLA2 expression. Mol Cells 2013; 36:400-9. [PMID: 24293010 PMCID: PMC3887938 DOI: 10.1007/s10059-013-0078-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Revised: 09/10/2013] [Accepted: 09/15/2013] [Indexed: 01/24/2023] Open
Abstract
Sepsis, a systemic inflammatory response syndrome, remains a potentially lethal condition. (S)-1-α-Naphthylmethyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline (CKD712) is noted as a drug candidate for sepsis. Many studies have demonstrated its significant anti-inflammatory effects. Here we first examined whether CKD712 inhibits lipopolysaccharide (LPS)-induced arachidonic acid (AA) release in the RAW 264.7 mouse monocyte cell line, and subsequently, its inhibitory mechanisms. CKD712 reversed LPS-associated morphological changes in the RAW 264.7 cells, and inhibited LPS-induced release of AA in a concentrationdependent manner. The inhibition was apparently due to the diminished expression of a cytosolic form of phospholipase A2 (cPLA2) by CKD712, resulting from reduced NF-κB activation. Furthermore, CKD712 inhibited the activation of ERK1/2 and SAP/JNK, but not of p38 MAPK. CKD712 had no effect on the activity or phosphorylation of cPLA2 and on calcium influx. Our results collectively suggest that CKD712 inhibits LPS-induced AA release through the inhibition of a MAPKs/NF-κB pathway leading to reduced cPLA2 expression in RAW 264.7 cells.
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Affiliation(s)
- Jong Min Choi
- Department of Environmental and Health Chemistry, College of Pharmacy, Chung-Ang University, Seoul 156-756, Korea
| | - Young Hwa Choi
- Department of Environmental and Health Chemistry, College of Pharmacy, Chung-Ang University, Seoul 156-756, Korea
| | - Seok Kyun Kim
- Department of Environmental and Health Chemistry, College of Pharmacy, Chung-Ang University, Seoul 156-756, Korea
| | - Kyong Hoon Ahn
- Department of Environmental and Health Chemistry, College of Pharmacy, Chung-Ang University, Seoul 156-756, Korea
| | - Jong Hoon Won
- Department of Environmental and Health Chemistry, College of Pharmacy, Chung-Ang University, Seoul 156-756, Korea
| | - Joo Hyuk Lim
- Department of Environmental and Health Chemistry, College of Pharmacy, Chung-Ang University, Seoul 156-756, Korea
| | - You Jin Jang
- Department of Environmental and Health Chemistry, College of Pharmacy, Chung-Ang University, Seoul 156-756, Korea
| | | | | | - Dae Kyong Kim
- Department of Environmental and Health Chemistry, College of Pharmacy, Chung-Ang University, Seoul 156-756, Korea
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Mo Y, Wan R, Feng L, Chien S, Tollerud DJ, Zhang Q. Combination effects of cigarette smoke extract and ambient ultrafine particles on endothelial cells. Toxicol In Vitro 2012; 26:295-303. [PMID: 22178768 PMCID: PMC3273600 DOI: 10.1016/j.tiv.2011.12.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Revised: 10/29/2011] [Accepted: 12/01/2011] [Indexed: 01/01/2023]
Abstract
Previous studies have shown that ambient ultrafine particles with diameters less than 100nm (UFPs) can pass from the lungs to the circulation because of their very small diameter, and induce lung oxidative stress with a resultant dysfunction of lung endothelial cells. However, no studies have addressed the potential combined effects of UFPs and cigarette smoke on vascular endothelial cells. We hypothesized that co-exposure to UFPs and cigarette smoke extract (CSE) may cause combined effects on activation of endothelial cells and dysfunction of endothelium by oxidative stress through activation of NADPH oxidase. We determined the effects of UFPs with or without CSE on mouse pulmonary microvascular endothelial cells (MPMVEC) obtained from C57BL/6J (wild-type) and gp91(phox) knock-out mice (gp91(phox) is one of the key components of NADPH oxidase, one of ROS generators). Our results showed that exposure of MPMVEC from wild-type mice to UFPs or CSE, at a non-toxic dose, induced reactive oxygen species (ROS) generation, increased phosphorylation of p38 and Erk1/2, and up-regulated early growth response -1 (Egr-1) and IL-6 genes. These effects were significantly enhanced when cells were co-exposed to both UFPs and CSE. However, exposure of MPMVEC from gp91(phox) knock-out mice did not induce the above effects. Furthermore, UFPs- and/or CSE-induced Egr-1 mRNA upregulation was attenuated significantly when cells were pre-treated with p38 specific inhibitor, SB 203580, or MEK1/2 inhibitor, PD98059, and Egr-1 siRNA treatment abolished UFPs- and/or CSE-induced overexpression of IL-6. Our results suggest that UFPs and/or CSE caused activation of NADPH oxidase, resulting in ROS generation that led to activation of MAPKs through induced phosphorylation of p38 and ERK1/2 MAPKs and upregulation of Egr-1. Those effects may further result in endothelial dysfunction through production of cytokines such as IL-6. Our results suggest that co-exposure to UFPs and CSE causes enhanced injury to endothelial cells.
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Affiliation(s)
- Yiqun Mo
- Department of Environmental and Occupational Health Sciences, School of Public Health and Information Sciences, University of Louisville, Louisville, KY, USA
| | - Rong Wan
- Department of Environmental and Occupational Health Sciences, School of Public Health and Information Sciences, University of Louisville, Louisville, KY, USA
| | - Lingfang Feng
- Department of Environmental and Occupational Health Sciences, School of Public Health and Information Sciences, University of Louisville, Louisville, KY, USA
- Department of Hygiene, Zhejiang Academy of Medical Sciences, Hangzhou, Zhejiang, P. R. of China
| | - Sufan Chien
- Department of Surgery, School of Medicine, University of Louisville, Louisville, KY, USA
| | - David J. Tollerud
- Department of Environmental and Occupational Health Sciences, School of Public Health and Information Sciences, University of Louisville, Louisville, KY, USA
| | - Qunwei Zhang
- Department of Environmental and Occupational Health Sciences, School of Public Health and Information Sciences, University of Louisville, Louisville, KY, USA
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Hu SQ, Ye JS, Zong YY, Sun CC, Liu DH, Wu YP, Song T, Zhang GY. S-nitrosylation of mixed lineage kinase 3 contributes to its activation after cerebral ischemia. J Biol Chem 2012; 287:2364-77. [PMID: 22123824 PMCID: PMC3268398 DOI: 10.1074/jbc.m111.227124] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2011] [Revised: 10/13/2011] [Indexed: 11/06/2022] Open
Abstract
Previous studies in our laboratory have shown that mixed lineage kinase 3 (MLK3) can be activated following global ischemia. In addition, other laboratories have reported that the activation of MLK3 may be linked to the accumulation of free radicals. However, the mechanism of MLK3 activation remains incompletely understood. We report here that MLK3, overexpressed in HEK293 cells, is S-nitrosylated (forming SNO-MLK3) via a reaction with S-nitrosoglutathione, an exogenous nitric oxide (NO) donor, at one critical cysteine residue (Cys-688). We further show that the S-nitrosylation of MLK3 contributes to its dimerization and activation. We also investigated whether the activation of MLK3 is associated with S-nitrosylation following rat brain ischemia/reperfusion. Our results show that the administration of 7-nitroindazole, an inhibitor of neuronal NO synthase (nNOS), or nNOS antisense oligodeoxynucleotides diminished the S-nitrosylation of MLK3 and inhibited its activation induced by cerebral ischemia/reperfusion. In contrast, 2-amino-5,6-dihydro-6-methyl-4H-1,3-thiazine (an inhibitor of inducible NO synthase) or nNOS missense oligodeoxynucleotides did not affect the S-nitrosylation of MLK3. In addition, treatment with sodium nitroprusside (an exogenous NO donor) and S-nitrosoglutathione or MK801, an antagonist of the N-methyl-D-aspartate receptor, also diminished the S-nitrosylation and activation of MLK3 induced by cerebral ischemia/reperfusion. The activation of MLK3 facilitated its downstream protein kinase kinase 4/7 (MKK4/7)-JNK signaling module and both nuclear and non-nuclear apoptosis pathways. These data suggest that the activation of MLK3 during the early stages of ischemia/reperfusion is modulated by S-nitrosylation and provides a potential new approach for stroke therapy whereby the post-translational modification machinery is targeted.
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Affiliation(s)
- Shu-Qun Hu
- From the Jiangsu Key Laboratory of Brain Disease Bioinformation and Research Center for Biochemistry and Molecular Biology and
| | - Jun-Song Ye
- From the Jiangsu Key Laboratory of Brain Disease Bioinformation and Research Center for Biochemistry and Molecular Biology and
| | - Yan-Yan Zong
- From the Jiangsu Key Laboratory of Brain Disease Bioinformation and Research Center for Biochemistry and Molecular Biology and
| | - Chang-Cheng Sun
- From the Jiangsu Key Laboratory of Brain Disease Bioinformation and Research Center for Biochemistry and Molecular Biology and
| | - Dong-Hai Liu
- From the Jiangsu Key Laboratory of Brain Disease Bioinformation and Research Center for Biochemistry and Molecular Biology and
| | - Yong-Ping Wu
- Jiangsu Key Laboratory of Anesthesiology, Xuzhou Medical College, Xuzhou, Jiangsu 221002 and
| | - Tao Song
- the Department of Anesthesiology, First Affiliated Hospital, China Medical University, Shenyang 110001, China
| | - Guang-Yi Zhang
- From the Jiangsu Key Laboratory of Brain Disease Bioinformation and Research Center for Biochemistry and Molecular Biology and
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10
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Won DP, Lee JS, Kwon DS, Lee KE, Shin WC, Hong EK. Immunostimulating activity by polysaccharides isolated from fruiting body of Inonotus obliquus. Mol Cells 2011; 31:165-73. [PMID: 21191814 PMCID: PMC3932689 DOI: 10.1007/s10059-011-0022-x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2010] [Revised: 10/27/2010] [Accepted: 11/23/2010] [Indexed: 12/22/2022] Open
Abstract
In this study, we investigated the immunostimulating activity of polysaccharides isolated from fruiting body of Inonotus obliquus (PFIO). Additionally, the signaling pathway of PFIO-mediated macrophage activation was investigated in RAW264.7 macrophage cells. We found that PFIO was capable of promoting NO/ROS production, TNF-α secretion and phagocytic uptake in macrophages, as well as cell proliferation, comitogenic effect and IFN-γ/IL-4 secretion in mouse splenocytes. PFIO was able to induce the phosphorylation of three MAPKs as well as the nuclear translocation of NF-κB, resulting in activation of RAW264.7 macrophages. PFIO also induced the inhibition of TNF-α secretion by anti-TLR2 mAb, consequently, PFIO might be involved in TNF-α secretion via the TLR2 receptor. In addition, our results showed that oral administration of PFIO suppressed in vivo growth of melanoma tumor in tumorbearing mice. In conclusion, our experiments presented that PFIO effectively promotes macrophage activation through the MAPK and NF-κB signaling pathways, suggesting that PFIO may potentially regulate the immune response.
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Affiliation(s)
| | | | | | | | | | - Eock Kee Hong
- Department of Bioengineering and Technology, Kangwon National University, Chuncheon 200-701, Korea
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Jesch SA, Gaspar ML, Stefan CJ, Aregullin MA, Henry SA. Interruption of inositol sphingolipid synthesis triggers Stt4p-dependent protein kinase C signaling. J Biol Chem 2010; 285:41947-60. [PMID: 20972263 PMCID: PMC3009921 DOI: 10.1074/jbc.m110.188607] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2010] [Revised: 10/22/2010] [Indexed: 11/06/2022] Open
Abstract
The protein kinase C (PKC)-MAPK signaling cascade is activated and is essential for viability when cells are starved for the phospholipid precursor inositol. In this study, we report that inhibiting inositol-containing sphingolipid metabolism, either by inositol starvation or treatment with agents that block sphingolipid synthesis, triggers PKC signaling independent of sphingoid base accumulation. Under these same growth conditions, a fluorescent biosensor that detects the necessary PKC signaling intermediate, phosphatidylinositol (PI)-4-phosphate (PI4P), is enriched on the plasma membrane. The appearance of the PI4P biosensor on the plasma membrane correlates with PKC activation and requires the PI 4-kinase Stt4p. Like other mutations in the PKC-MAPK pathway, mutants defective in Stt4p and the PI4P 5-kinase Mss4p, which generates phosphatidylinositol 4,5-bisphosphate, exhibit inositol auxotrophy, yet fully derepress INO1, encoding inositol-3-phosphate synthase. These observations suggest that inositol-containing sphingolipid metabolism controls PKC signaling by regulating access of the signaling lipids PI4P and phosphatidylinositol 4,5-bisphosphate to effector proteins on the plasma membrane.
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Affiliation(s)
| | | | - Christopher J. Stefan
- From the Department of Molecular Biology and Genetics and
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, New York 14853
| | | | - Susan A. Henry
- From the Department of Molecular Biology and Genetics and
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12
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Choi YJ, Arzuaga X, Kluemper CT, Caraballo A, Toborek M, Hennig B. Quercetin blocks caveolae-dependent pro-inflammatory responses induced by co-planar PCBs. Environ Int 2010; 36:931-934. [PMID: 19608276 PMCID: PMC2889233 DOI: 10.1016/j.envint.2009.06.009] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2008] [Revised: 01/13/2009] [Accepted: 06/07/2009] [Indexed: 05/28/2023]
Abstract
Polychlorinated biphenyls (PCBs) are widespread environmental contaminants, and co-planar PCBs can induce oxidative stress and activation of pro-inflammatory signaling cascades which are associated with atherosclerosis. The majority of the toxicological effects elicited by the co-planar PCB exposure are associated to the activation of the aryl hydrocarbon receptor (AHR) and subsequent induction of responsive genes. Previous studies from our group have shown that quercetin, a nutritionally relevant flavonoid can significantly reduce PCB77 induction of oxidative stress and expression of the AHR responsive gene cytochrome P450 1A1 (CYP1A1). We also have evidence that membrane domains called caveolae may regulate PCB-induced inflammatory parameters. Thus, we hypothesized that quercetin can modulate PCB-induced endothelial inflammation associated with caveolae. To test this hypothesis, endothelial cells were exposed to co-planar PCBs in combination with quercetin, and the expression of pro-inflammatory genes was analyzed by real-time PCR. Quercetin co-treatment significantly blocked both PCB77 and PCB126 induction of CYP1A1, vascular cell adhesion molecule 1 (VCAM-1), E-selectin and P-selectin. Exposure to PCB77 also induced caveolin-1 protein expression, which was reduced by co-treatment with quercetin. Our results suggest that inflammatory pathways induced by co-planar PCBs can be down-regulated by the dietary flavonoid quercetin through mechanisms associated with functional caveolae.
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Affiliation(s)
- Yean Jung Choi
- Molecular and Cell Nutrition Laboratory, College of Agriculture, University of Kentucky, Lexington, USA
| | - Xabier Arzuaga
- Molecular and Cell Nutrition Laboratory, College of Agriculture, University of Kentucky, Lexington, USA
| | | | - Adelka Caraballo
- Department of Biology, University of Puerto Rico, Rio Piedras, Puerto Rico
| | - Michal Toborek
- Department of Neurosurgery, University of Kentucky, Lexington, USA
| | - Bernhard Hennig
- Molecular and Cell Nutrition Laboratory, College of Agriculture, University of Kentucky, Lexington, USA
- Graduate Center for Toxicology, University of Kentucky, Lexington, USA
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13
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Suram S, Gangelhoff TA, Taylor PR, Rosas M, Brown GD, Bonventre JV, Akira S, Uematsu S, Williams DL, Murphy RC, Leslie CC. Pathways regulating cytosolic phospholipase A2 activation and eicosanoid production in macrophages by Candida albicans. J Biol Chem 2010; 285:30676-85. [PMID: 20643646 PMCID: PMC2945562 DOI: 10.1074/jbc.m110.143800] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2010] [Revised: 07/13/2010] [Indexed: 12/13/2022] Open
Abstract
Resident tissue macrophages are activated by the fungal pathogen Candida albicans to release eicosanoids, which are important modulators of inflammation and immune responses. Our objective was to identify the macrophage receptors engaged by C. albicans that mediate activation of group IVA cytosolic phospholipase A(2) (cPLA(2)α), a regulatory enzyme that releases arachidonic acid (AA) for production of prostaglandins and leukotrienes. A comparison of peritoneal macrophages from wild type and knock-out mice demonstrates that the β-glucan receptor Dectin-1 and MyD88 regulate early release of AA and eicosanoids in response to C. albicans. However, cyclooxygenase 2 (COX2) expression and later phase eicosanoid production are defective in MyD88(-/-) but not Dectin-1(-/-) macrophages. Furthermore, C. albicans-stimulated activation of MAPK and phosphorylation of cPLA(2)α on Ser-505 are regulated by MyD88 and not Dectin-1. In contrast, Dectin-1 mediates MAPK activation, cPLA(2)α phosphorylation, and COX2 expression in response to particulate β-glucan suggesting that other receptors engaged by C. albicans preferentially mediate these responses. Results also implicate the mannan-binding receptor Dectin-2 in regulating cPLA(2)α. C. albicans-stimulated MAPK activation and AA release are blocked by d-mannose and Dectin-2-specific antibody, and overexpression of Dectin-2 in RAW264.7 macrophages enhances C. albicans-stimulated MAPK activation, AA release, and COX2 expression. In addition, calcium mobilization is enhanced in RAW264.7 macrophages overexpressing Dectin-1 or -2. The results demonstrate that C. albicans engages both β-glucan and mannan-binding receptors on macrophages that act with MyD88 to regulate the activation of cPLA(2)α and eicosanoid production.
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Affiliation(s)
- Saritha Suram
- From the Department of Pediatrics, National Jewish Health, Denver, Colorado 80206
| | - Todd A. Gangelhoff
- From the Department of Pediatrics, National Jewish Health, Denver, Colorado 80206
| | - Philip R. Taylor
- the Department of Infection, Immunity, and Biochemistry, School of Medicine, Cardiff University, CF14 4XN Cardiff, United Kingdom
| | - Marcela Rosas
- the Department of Infection, Immunity, and Biochemistry, School of Medicine, Cardiff University, CF14 4XN Cardiff, United Kingdom
| | - Gordon D. Brown
- the Institute of Medical Sciences, University of Aberdeen, AB25 22D Aberdeen, Scotland, United Kingdom
| | - Joseph V. Bonventre
- the Renal Division, Brigham and Women's Hospital, Boston, Massachusetts 02115
| | - Shizuo Akira
- the Department of Host Defense, Research Institute for Microbial Diseases, Osaka University, 565-0871 Osaka, Japan
| | - Satoshi Uematsu
- the Department of Host Defense, Research Institute for Microbial Diseases, Osaka University, 565-0871 Osaka, Japan
| | - David L. Williams
- the Department of Surgery, James H. Quillen College of Medicine, Johnson City, Tennessee 37614, and
| | | | - Christina C. Leslie
- From the Department of Pediatrics, National Jewish Health, Denver, Colorado 80206
- the Departments of Pathology and Pharmacology, University of Colorado Denver, Aurora, Colorado 80045
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14
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Mendelson K, Swendeman S, Saftig P, Blobel CP. Stimulation of platelet-derived growth factor receptor beta (PDGFRbeta) activates ADAM17 and promotes metalloproteinase-dependent cross-talk between the PDGFRbeta and epidermal growth factor receptor (EGFR) signaling pathways. J Biol Chem 2010; 285:25024-32. [PMID: 20529858 PMCID: PMC2915738 DOI: 10.1074/jbc.m110.102566] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2010] [Revised: 05/25/2010] [Indexed: 11/06/2022] Open
Abstract
Binding of the platelet-derived growth factor (PDGF)-B to its receptor PDGFRbeta promotes proliferation, migration, and recruitment of pericytes and smooth muscle cells to endothelial cells, serving to stabilize developing blood vessels. The main goals of this study were to determine whether the extracellular domain of the PDGFRbeta can be proteolytically released from cell membranes and, if so, to identify the responsible sheddase and determine whether activation of the PDGFRbeta stimulates its shedding and potentially that of other membrane proteins. We found that the PDGFRbeta is shed from cells by a metalloproteinase and used loss-of-function experiments to identify ADAM10 as the sheddase responsible for constitutive and ionomycin-stimulated processing of the PDGFRbeta. Moreover, we showed that ligand-dependent activation of the PDGFRbeta does not trigger its own shedding by ADAM10, but instead it stimulates ADAM17 and shedding of substrates of ADAM17, including tumor necrosis factor alpha and transforming growth factor alpha. Finally, we demonstrated that treatment of mouse embryonic fibroblasts with PDGF-B triggers a metalloproteinase-dependent cross-talk between the PDGFRbeta and the epidermal growth factor receptor (EGFR)/ERK1/2 signaling axis that is also critical for PDGF-B-stimulated cell migration, most likely via ADAM17-dependent release and activation of ligands of the EGFR. This study identifies the principal sheddase for the PDGFRbeta and provides new insights into the mechanism of PDGFRbeta-dependent signal transduction and cross-talk with the EGFR.
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Affiliation(s)
- Karen Mendelson
- From the Arthritis and Tissue Degeneration Program, The Hospital for Special Surgery, New York, New York 10021
- the Physiology, Biophysics, and Systems Biology Program, Weill Medical College of Cornell University, New York, New York 10021
| | - Steven Swendeman
- From the Arthritis and Tissue Degeneration Program, The Hospital for Special Surgery, New York, New York 10021
| | - Paul Saftig
- the Biochemical Institute, Christian-Albrechts-University, D-24098 Kiel, Germany, and
| | - Carl P. Blobel
- From the Arthritis and Tissue Degeneration Program, The Hospital for Special Surgery, New York, New York 10021
- the Physiology, Biophysics, and Systems Biology Program, Weill Medical College of Cornell University, New York, New York 10021
- the Department of Medicine, Weill Medical College of Cornell University, New York, New York 10021
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15
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Pal A, Tewari-Singh N, Gu M, Agarwal C, Huang J, Day BJ, White CW, Agarwal R. Sulfur mustard analog induces oxidative stress and activates signaling cascades in the skin of SKH-1 hairless mice. Free Radic Biol Med 2009; 47:1640-51. [PMID: 19761830 PMCID: PMC2801552 DOI: 10.1016/j.freeradbiomed.2009.09.011] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2009] [Revised: 08/20/2009] [Accepted: 09/09/2009] [Indexed: 12/16/2022]
Abstract
A monofunctional analog of the chemical warfare agent sulfur mustard (HD), 2-chloroethyl ethyl sulfide (CEES), induces tissue damage similar to HD. Herein we studied the molecular mechanisms associated with CEES-induced skin inflammation and toxicity in SKH-1 hairless mice. Topical CEES exposure caused an increase in oxidative stress as observed by enhanced 4-hydroxynonenal and 5,5-dimethyl-2-(8-octanoic acid)-1-pyrroline N-oxide protein adduct formation and an increase in protein oxidation. The CEES-induced increase in the formation of 8-oxo-2-deoxyguanosine indicated DNA oxidation. CEES exposure instigated an increase in the phosphorylation of mitogen-activated protein kinases (MAPKs; ERK1/2, JNK, and p38). After CEES exposure, a significant increase in the phosphorylation of Akt at Ser473 and Thr308 was observed as well as upregulation of its upstream effector, PDK1, in mouse skin tissue. Subsequently, CEES exposure caused activation of AP-1 family proteins and the NF-kappaB pathway, including phosphorylation and degradation of IkappaBalpha in addition to phosphorylation of the NF-kappaB essential modulator. Collectively, our results indicate that CEES induces oxidative stress and the activation of the transcription factors AP-1 and NF-kappaB via upstream signaling pathways including MAPKs and Akt in SKH-1 hairless mouse skin. These novel molecular targets could be supportive in the development of prophylactic and therapeutic interventions against HD-related skin injury.
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Affiliation(s)
- Arttatrana Pal
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Colorado at Denver, Aurora, CO 80045, USA
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16
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Arnott JA, Zhang X, Sanjay A, Owen TA, Smock SL, Rehman S, DeLong WG, Safadi FF, Popoff SN. Molecular requirements for induction of CTGF expression by TGF-beta1 in primary osteoblasts. Bone 2008; 42:871-85. [PMID: 18314002 PMCID: PMC2430079 DOI: 10.1016/j.bone.2008.01.006] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2007] [Revised: 11/30/2007] [Accepted: 01/03/2008] [Indexed: 01/05/2023]
Abstract
Connective tissue growth factor (CTGF/CCN2) is a cysteine rich, extracellular matrix protein that acts as an anabolic growth factor to regulate osteoblast differentiation and function. In osteoblasts, CTGF is induced by TGF-beta1 where it acts as a downstream mediator of TGF-beta1 induced matrix production. The molecular mechanisms that control CTGF induction by TGF-beta1 in osteoblasts are not known. To assess the role of individual Smads in mediating the induction of CTGF by TGF-beta1, we used specific Smad siRNAs to block Smad expression. These studies demonstrated that Smads 3 and 4, but not Smad 2, are required for TGF-beta1 induced CTGF promoter activity and expression in osteoblasts. Since the activation of MAPKs (Erk, Jnk and p38) by TGF-beta1 is cell type specific, we were interested in determining the role of individual MAPKs in TGF-beta1 induction of CTGF promoter activity and expression. Using dominant negative (DN) mutants for Erk, Jnk and p38, we demonstrated that the expression of DN-Erk caused a significant inhibition of TGF-beta1 induced CTGF promoter activity. In contrast, the expression of DN-p38 or DN-Jnk failed to inhibit activation of CTGF promoter activity. To confirm the vital role of Erk, we used the Erk inhibitor (PD98059) to block its activation, demonstrating that it prevented TGF-beta1 activation of the CTGF promoter and up-regulation of CTGF expression in osteoblasts. Since Src can also act as a downstream signaling effector for TGF-beta in some cell types, we determined its role in TGF-beta1 induction of CTGF in osteoblasts. Treatment of osteoblasts with a Src family kinase inhibitor, PP2, or the expression of two independent kinase-dead Src mutant constructs caused significant inhibition of TGF-beta1 induced CTGF promoter activity and expression. Additionally, blocking Src activation prevented Erk activation by TGF-beta1 demonstrating a role for Src as an upstream mediator of Erk in regulating CTGF expression in osteoblasts. To investigate the involvement of the TGF-beta1 response element (TRE) and the SMAD binding element (SBE) in CTGF induction, we cloned the rat CTGF proximal promoter (-787 to +1) containing the TRE and SBE motifs into a pGL3-Luciferase reporter construct. Using a combination of CTGF promoter deletion constructs and site-directed mutants, we demonstrated the unique requirement of both the TRE and SBE for CTGF induction by TGF-beta1 in osteoblasts. Electro-mobility shift assays using specific probes containing the TRE, SBE or both showed TGF-beta1 inducible complexes that can be ablated by mutation of the respective motif, confirming their requirement for TGF-beta1 induced CTGF promoter activity. In conclusion, these studies demonstrate that CTGF induction by TGF-beta1 in osteoblasts involves Smads 3 and 4, the Erk and Src signaling pathways, and requires both the TRE and SBE motifs in the CTGF proximal promoter.
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Affiliation(s)
- J A Arnott
- Department of Anatomy and Cell Biology, Temple University School of Medicine, Philadelphia, PA 19140, USA
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17
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Abstract
The evidence for the promising potential for derivatives of Vitamin D (deltanoids) in the treatment of myeloid leukemias is increasing, but currently is not matched by the understanding of the precise mechanisms by which these anti-neoplastic effects are achieved. Unlike solid tumors in which growth retardation by deltanoids appears to result from inhibition of cell proliferation and the promotion of cell death by apoptosis, control of myeloid leukemia proliferation by deltanoids results from the induction of differentiation of the immature myelo-monocytic cells towards functional monocytic cells. We present here the accumulating evidence that a pathway that is initiated by deltanoid activation of Vitamin D receptor (VDR) and leads to monocytic differentiation of human myeloblastic HL60 cells, includes the MEK-ERK and JNK mitogen-activated protein kinases (MAPKs), their positive and negative regulators and a downstream effector C/EBPbeta. As in other cells, the abundance of VDR protein increases shortly after an exposure of HL60 cells to 1alpha,25-dihydroxyvitamin D(3) (1alpha,25(OH)(2) D(3)). Other early events include a parallel upregulation of kinase suppressor of Ras (KSR-1) and the activation of the ERK MAPK pathway and data suggest that KSR-1 acts to amplify the signal provided by low concentrations of 1alpha,25(OH)(2) D(3). Maintenance of monocytic differentiation may be enhanced by JNK, but diminished by p38, MAPK signaling. Downstream, one of the targets of these pathways is C/EBPbeta, which can directly interact with the promoter for CD14, a gene characteristically expressed in monocytes. Importantly, in freshly obtained acute myeloid leukemia (AML)-M2 cells exposed to PRI-2191, a novel deltanoid with a modified side chain, upregulation of C/EBPbeta paralleled the induction of monocytic differentiation. These data provide a basis for the hypothesis that deltanoid-induced upregulation of C/EBPbeta bypasses the block to granulocytic differentiation in myeloid leukemia cells by redirecting the cells to monocytic differentiation.
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Affiliation(s)
- George P Studzinski
- Department of Pathology and Medicine, UMDNJ, New Jersey Medical School, Newark 07103, USA.
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Zhen X, Du W, Romano AG, Friedman E, Harvey JA. The p38 mitogen-activated protein kinase is involved in associative learning in rabbits. J Neurosci 2001; 21:5513-9. [PMID: 11466422 PMCID: PMC6762655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023] Open
Abstract
This study examined the role of the mitogen-activated protein kinase (MAPK) family during acquisition of the rabbit's classically conditioned eye-blink response. Eye-blink conditioning produced a significant, bilateral activation of both extracellular signal-regulated protein kinases (ERKs) and p38 MAPK in the anterior cerebellar vermis. There was also a significant bilateral activation of ERKs in the dorsal hippocampus with no change in p38 MAPK. These changes were seen at 2 min after the last conditioning session, were maintained for at least 180 min, and occurred without any change in the protein expression of either ERKs or p38 MAPK. There were no changes in ERKs or p38 MAPK in frontal cortex, in cerebellar hemispheral lobule VI, or in a section of brainstem containing the inferior olive. Moreover, the stress-related protein kinase Jun N-terminal kinase (JNK), another subfamily of MAPKs, was not altered in any of the brain regions examined. Animals receiving explicitly unpaired presentations of a conditioned stimulus and an unconditioned stimulus did not acquire conditioned responses (CRs) and did not demonstrate any changes in ERKs, p38 MAPK, or JNK. The intraventricular injection of SB203580, a selective p38 MAPK inhibitor, significantly retarded CR acquisition and blocked the learning-related increases in p38 MAPK activity in the anterior vermis. PD98059, a selective MAPK kinase inhibitor, had a smaller and only marginally significant effect on CR acquisition, although it did block the learning-related increases in ERK activity in both the hippocampus and anterior vermis. These results indicate that p38 MAPK is activated during associative learning and may play a role in the transcriptional events that lead to memory consolidation.
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Affiliation(s)
- X Zhen
- Department of Pharmacology and Physiology, MCP Hahnemann University School of Medicine, Philadelphia, Pennsylvania 19102, USA.
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