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Martens MD, Fernando AS, Gordon JW. A new trick for an old dog? Myocardial-specific roles for prostaglandins as mediators of ischemic injury and repair. Am J Physiol Heart Circ Physiol 2021; 320:H2169-H2184. [PMID: 33861147 DOI: 10.1152/ajpheart.00872.2020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The small lipid-derived paracrine signaling molecules known as prostaglandins have been recognized for their ability to modulate many facets of cardiovascular physiology since their initial discovery more than 85 years ago. Although the role of prostaglandins in the vasculature has gained significant attention across time, a handful of historical studies have also directly implicated the cardiomyocyte in both prostaglandin synthesis and release. Recently, our understanding of how prostaglandin receptor modulation impacts and contributes to myocardial structure and function has gained attention while leaving most other components of myocardial prostaglandin metabolism and signaling unexplored. This mini-review highlights both the key historical studies that underpin modern prostaglandin research in the heart, while concurrently presenting the latest findings related to how prostaglandin metabolism and signaling impact myocardial injury and repair.
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Affiliation(s)
- Matthew D Martens
- Department of Human Anatomy and Cell Science, Rady Faculty of Health Science, University of Manitoba, Winnipeg, Manitoba, Canada.,The Diabetes Research Envisioned and Accomplished in Manitoba (DREAM) Theme, Children's Hospital Research Institute of Manitoba, Winnipeg, Manitoba, Canada
| | - Amy S Fernando
- The Diabetes Research Envisioned and Accomplished in Manitoba (DREAM) Theme, Children's Hospital Research Institute of Manitoba, Winnipeg, Manitoba, Canada
| | - Joseph W Gordon
- Department of Human Anatomy and Cell Science, Rady Faculty of Health Science, University of Manitoba, Winnipeg, Manitoba, Canada.,College of Nursing, Rady Faculty of Health Science, University of Manitoba, Winnipeg, Manitoba, Canada.,The Diabetes Research Envisioned and Accomplished in Manitoba (DREAM) Theme, Children's Hospital Research Institute of Manitoba, Winnipeg, Manitoba, Canada
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2
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Wang Y, Liu Y, Zhang M, Lv L, Zhang X, Zhang P, Zhou Y. Inhibition of PTGS1 promotes osteogenic differentiation of adipose-derived stem cells by suppressing NF-kB signaling. Stem Cell Res Ther 2019; 10:57. [PMID: 30760327 PMCID: PMC6375160 DOI: 10.1186/s13287-019-1167-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Revised: 01/30/2019] [Accepted: 02/04/2019] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Tissue inflammation is an important problem in the field of human adipose-derived stem cell (ASC)-based therapeutic bone regeneration. Many studies indicate that inflammatory cytokines are disadvantageous for osteogenic differentiation and bone formation. Therefore, overcoming inflammation would be greatly beneficial in promoting ASC-mediated bone regeneration. The present study aims to investigate the potential anti-inflammatory role of Prostaglandin G/H synthase 1 (PTGS1) during the osteogenic differentiation of ASCs. METHODS We performed TNFα treatment to investigate the response of PTGS1 to inflammation. Loss- and gain-of-function experiments were applied to investigate the function of PTGS1 in the osteogenic differentiation of ASCs ex vivo and in vivo. Western blot and confocal analyses were used to determine the molecular mechanism of PTGS1-regulated osteogenic differentiation. RESULTS Our work demonstrates that PTGS1 expression is significantly increased upon inflammatory cytokine treatment. Both ex vivo and in vivo studies indicate that PTGS1 is required for the osteogenic differentiation of ASCs. Mechanistically, we show that PTGS1 regulates osteogenesis of ASCs via modulating the NF-κB signaling pathway. CONCLUSIONS Collectively, this work confirms that the PTGS1-NF-κB signaling pathway is a novel molecular target for ASC-mediated regenerative medicine.
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Affiliation(s)
- Yuejun Wang
- Department of Prosthodontics, Peking University School and Hospital of Stomatology, 22 Zhongguancun South Avenue, Haidian District, Beijing, 100081, China.,National Engineering Lab for Digital and Material Technology of Stomatology, Peking University School and Hospital of Stomatology, Beijing, 100081, China
| | - Yunsong Liu
- Department of Prosthodontics, Peking University School and Hospital of Stomatology, 22 Zhongguancun South Avenue, Haidian District, Beijing, 100081, China.,National Engineering Lab for Digital and Material Technology of Stomatology, Peking University School and Hospital of Stomatology, Beijing, 100081, China
| | - Min Zhang
- Department of Prosthodontics, Peking University School and Hospital of Stomatology, 22 Zhongguancun South Avenue, Haidian District, Beijing, 100081, China.,National Engineering Lab for Digital and Material Technology of Stomatology, Peking University School and Hospital of Stomatology, Beijing, 100081, China
| | - Longwei Lv
- Department of Prosthodontics, Peking University School and Hospital of Stomatology, 22 Zhongguancun South Avenue, Haidian District, Beijing, 100081, China.,National Engineering Lab for Digital and Material Technology of Stomatology, Peking University School and Hospital of Stomatology, Beijing, 100081, China
| | - Xiao Zhang
- Department of Prosthodontics, Peking University School and Hospital of Stomatology, 22 Zhongguancun South Avenue, Haidian District, Beijing, 100081, China.,National Engineering Lab for Digital and Material Technology of Stomatology, Peking University School and Hospital of Stomatology, Beijing, 100081, China
| | - Ping Zhang
- Department of Prosthodontics, Peking University School and Hospital of Stomatology, 22 Zhongguancun South Avenue, Haidian District, Beijing, 100081, China. .,National Engineering Lab for Digital and Material Technology of Stomatology, Peking University School and Hospital of Stomatology, Beijing, 100081, China.
| | - Yongsheng Zhou
- Department of Prosthodontics, Peking University School and Hospital of Stomatology, 22 Zhongguancun South Avenue, Haidian District, Beijing, 100081, China. .,National Engineering Lab for Digital and Material Technology of Stomatology, Peking University School and Hospital of Stomatology, Beijing, 100081, China.
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3
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Hewett SJ, Shi J, Gong Y, Dhandapani K, Pilbeam C, Hewett JA. Spontaneous Glutamatergic Synaptic Activity Regulates Constitutive COX-2 Expression in Neurons: OPPOSING ROLES FOR THE TRANSCRIPTION FACTORS CREB (cAMP RESPONSE ELEMENT BINDING) PROTEIN AND Sp1 (STIMULATORY PROTEIN-1). J Biol Chem 2016; 291:27279-27288. [PMID: 27875294 DOI: 10.1074/jbc.m116.737353] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 11/10/2016] [Indexed: 11/06/2022] Open
Abstract
Burgeoning evidence supports a role for cyclooxygenase metabolites in regulating membrane excitability in various forms of synaptic plasticity. Two cyclooxygenases, COX-1 and COX-2, catalyze the initial step in the metabolism of arachidonic acid to prostaglandins. COX-2 is generally considered inducible, but in glutamatergic neurons in some brain regions, including the cerebral cortex, it is constitutively expressed. However, the transcriptional mechanisms by which this occurs have not been elucidated. Here, we used quantitative PCR and also analyzed reporter gene expression in a mouse line carrying a construct consisting of a portion of the proximal promoter region of the mouse COX-2 gene upstream of luciferase cDNA to characterize COX-2 basal transcriptional regulation in cortical neurons. Extracts from the whole brain and from the cerebral cortex, hippocampus, and olfactory bulbs exhibited high luciferase activity. Moreover, constitutive COX-2 expression and luciferase activity were detected in cortical neurons, but not in cortical astrocytes, cultured from wild-type and transgenic mice, respectively. Constitutive COX-2 expression depended on spontaneous but not evoked excitatory synaptic activity and was shown to be N-methyl-d-aspartate receptor-dependent. Constitutive promoter activity was reduced in neurons transfected with a dominant-negative cAMP response element binding protein (CREB) and was eliminated by mutating the CRE-binding site on the COX-2 promoter. However, mutation of the stimulatory protein-1 (Sp1)-binding site resulted in an N-methyl-d-aspartate receptor-dependent enhancement of COX-2 promoter activity. Basal binding of the transcription factors CREB and Sp1 to the native neuronal COX-2 promoter was confirmed. In toto, our data suggest that spontaneous glutamatergic synaptic activity regulates constitutive neuronal COX-2 expression via Sp1 and CREB protein-dependent transcriptional mechanisms.
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Affiliation(s)
- Sandra J Hewett
- From the Department of Biology, Program in Neuroscience, Syracuse University, Syracuse, New York 13210,
| | - Jingxue Shi
- From the Department of Biology, Program in Neuroscience, Syracuse University, Syracuse, New York 13210
| | - Yifan Gong
- From the Department of Biology, Program in Neuroscience, Syracuse University, Syracuse, New York 13210
| | - Krishnan Dhandapani
- the Department of Neurosurgery, Medical College of Georgia, Augusta University, Augusta, Georgia 30912, and
| | - Carol Pilbeam
- the Department of Medicine, University of Connecticut Health Center, Farmington, Connecticut 06030
| | - James A Hewett
- From the Department of Biology, Program in Neuroscience, Syracuse University, Syracuse, New York 13210,
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4
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Kapitanović Vidak H, Catela Ivković T, Vidak Z, Kapitanović S. COX-1 and COX-2 polymorphisms in susceptibility to cerebral palsy in very preterm infants. Mol Neurobiol 2016; 54:930-938. [PMID: 26781425 DOI: 10.1007/s12035-016-9713-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 01/11/2016] [Indexed: 12/21/2022]
Abstract
Cerebral palsy (CP) is a nonprogressive motor disorder caused by white matter damage in the developing brain. Recent epidemiological and clinical data suggest intrauterine infection/inflammation as the most common cause of preterm delivery and neonatal complications, including CP. Cyclooxygenases are key enzymes in the conversion of arachidonic acid to prostaglandins. The COX family consists of two isoforms, COX-1 and COX-2. In the brain, COX-2 is constitutively expressed at high levels on pyramidal neurons, while COX-1 is predominantly expressed by microglia and can be upregulated in pathological conditions, such as infection, ischemia and traumatic brain injury. Single nucleotide polymorphisms in the COX-1 and COX-2 gene could have profound effects on COX-1 and COX-2 expression and, directly or indirectly, influence the pathogenesis, development and severity of CP. In this study we investigated the association between single nucleotide polymorphisms of the COX-1 and COX-2 gene and susceptibility to cerebral palsy in very preterm infants. The results of our study showed the association between COX-1 high expression genotype (-842 AA) and COX-1 high expression allele -842A and risk of CP in infants with cystic periventricular leucomalacia (cPVL). Our results support an important role of COX-1 enzyme on microglial activation during neuroinflammation resulting in huge neuroinflammatory response and the proinflammatory mediator overproduction, with the serious white matter damage and CP development as a consequence.
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Affiliation(s)
- Helena Kapitanović Vidak
- Special Hospital for Children with Neurodevelopmental and Motor Difficulties, Goljak 2, Zagreb, Croatia.
| | - Tina Catela Ivković
- Laboratory for Personalized Medicine, Division of Molecular Medicine, Ruđer Bošković Institute, Bijenička c. 54, Zagreb, Croatia
| | - Zoran Vidak
- Department of Obstetrics and Gynecology, Division of Neonatology, Clinical Hospital Merkur, Ivana Zajca 19, Zagreb, Croatia
| | - Sanja Kapitanović
- Laboratory for Personalized Medicine, Division of Molecular Medicine, Ruđer Bošković Institute, Bijenička c. 54, Zagreb, Croatia
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5
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Yang DH, Hsu CF, Lin CY, Guo JY, Yu WC, Chang VH. Krüppel-like factor 10 upregulates the expression of cyclooxygenase 1 and further modulates angiogenesis in endothelial cell and platelet aggregation in gene-deficient mice. Int J Biochem Cell Biol 2013. [DOI: 10.1016/j.biocel.2012.11.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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6
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Bondar’ TN, Kravchenko NA. Polymorphism of the cyclooxigenase-1 gene and aspirin resistance. CYTOL GENET+ 2012. [DOI: 10.3103/s0095452712040044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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7
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Provenzano C, Pascucci B, Lupari E, Civitareale D. Large scale analysis of transcription factor TTF-1/NKX2.1 target genes in GnRH secreting cell line GT1-7. Mol Cell Endocrinol 2010; 323:215-23. [PMID: 20211691 DOI: 10.1016/j.mce.2010.02.038] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2009] [Revised: 02/26/2010] [Accepted: 02/28/2010] [Indexed: 11/24/2022]
Abstract
TTF-1/Nkx2.1 is a homeodomain-containing transcription factor required for the proper development of ventral forebrain, including some structures of the hypothalamus. TTF-1/Nkx2.1 remains expressed in the hypothalamus after birth and it plays a crucial role during sexual development. To identify putative TTF-1/Nkx2.1 target genes in GnRH neurons, we have studied the gene expression profile of the GT1-7 cells exogenously expressing TTF-1/Nkx2.1 coding gene. Our transcriptome analysis confirms that TTF-1/Nkx2.1 is involved in neuron morphogenesis and differentiation. Many of the newly identified TTF-1/Nkx2.1 target genes have a direct involvement with the central regulation of sexual maturity. In particular, we have identified Sparc as a gene directly regulated by TTF-1/Nkx2.1 at the promoter level. To further support the role of TTF-1 in GnRH neurons, we show that Sparc is involved in the regulation of the GnRH secretion in GT1-7 cells.
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Affiliation(s)
- Claudia Provenzano
- Institute of Neurobiology and Molecular Medicine, CNR, Via Fosso del Cavaliere 100, 00133 Rome, Italy
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8
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Mbonye UR, Song I. Posttranscriptional and posttranslational determinants of cyclooxygenase expression. BMB Rep 2009; 42:552-60. [PMID: 19788855 DOI: 10.5483/bmbrep.2009.42.9.552] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Cyclooxygenases (COX-1 and COX-2) are ER-resident proteins that catalyze the committed step in prostanoid synthesis. COX-1 is constitutively expressed in many mammalian cells, whereas COX-2 is usually expressed inducibly and transiently. Abnormal expression of COX-2 has been implicated in the pathogenesis of chronic inflammation and various cancers; therefore, it is subject to tight and complex regulation. Differences in regulation of the COX enzymes at the posttranscriptional and posttranslational levels also contribute significantly to their distinct patterns of expression. Rapid degradation of COX-2 mRNA has been attributed to AU-rich elements (AREs) at its 3' UTR. Recently, microRNAs that can selectively repress COX-2 protein synthesis have been identified. The mature forms of these COX proteins are very similar in structure except that COX-2 has a unique 19-amino acid (19-aa) segment located near the C-terminus. This C-terminal 19-aa cassette plays an important role in mediation of the entry of COX-2 into the ER-associated degradation (ERAD) system, which transports ER proteins to the cytoplasm for degradation by the 26S proteasome. A second pathway for COX-2 protein degradation is initiated after the enzyme undergoes suicide inactivation following cyclooxygenase catalysis. Here, we discuss these molecular determinants of COX-2 expression in detail. [BMB reports 2009; 42(9): 552-560].
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Affiliation(s)
- Uri R Mbonye
- Department of Life Science, University of Seoul, Seoul 130-743, Korea
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9
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Arisawa T, Tahara T, Shibata T, Nagasaka M, Nakamura M, Kamiya Y, Fujita H, Yoshioka D, Arima Y, Okubo M, Hirata I, Nakano H. Genetic polymorphisms of cyclooxygenase-1 (COX-1) are associated with functional dyspepsia in Japanese women. J Womens Health (Larchmt) 2008; 17:1039-43. [PMID: 18582172 DOI: 10.1089/jwh.2007.0720] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Prostaglandins (PGs), catalyzed from arachidonic acid by cyclooxygenase (COX), are involved in a variety of physiological processes in the stomach. COX-1 has been regarded as a constitutively expressed enzyme that generates prostaglandins for gastrointestinal integrity. We investigated the association between the potentially functional polymorphism T-1676C in the COX-1 gene promoter and functional dyspepsia (FD) in the Japanese population. METHODS The study was performed in 272 subjects (185 with no upper abdominal symptoms and 87 with FD). We employed the PCR-SSCP method to detect the gene polymorphism. RESULTS Overall, female sex had a 2-2.5-fold risk for the development of FD compared with male sex, whereas the COX-1 gene polymorphism and Helicobacter pylori infection were not associated with susceptibility to FD. However, in female subjects, -1676T allele carriers had a significantly increased risk for the development of FD (OR 2.70, 95%CI 1.04-6.99, p = 0.041), especially the epigastric pain syndrome (EPS) subgroup (OR 4.07, 95%CI 1.15-14.4, p = 0.029). CONCLUSIONS Our results provide the first evidence that the COX-1 gene polymorphism is significantly associated with the development of the EPS subgroup of FD in female subjects.
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Affiliation(s)
- Tomiyasu Arisawa
- Department of Gatroenterology, Fujita Health University School of Medicine 1-98, Dengakugakubo, Kutsukake-cho, Toyoake 470-1192, Japan.
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10
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Healy ZR, Zhu F, Stull JD, Konstantopoulos K. Elucidation of the signaling network of COX-2 induction in sheared chondrocytes: COX-2 is induced via a Rac/MEKK1/MKK7/JNK2/c-Jun-C/EBPβ-dependent pathway. Am J Physiol Cell Physiol 2008; 294:C1146-57. [DOI: 10.1152/ajpcell.00542.2007] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Shear stress is a pathophysiologically relevant mechanical signal in cartilage biology and tissue engineering. Cyclooxygenase-2 (COX-2) is a pivotal proinflammatory enzyme, which is induced by mechanical loading-derived shear stress in chondrocytes. In the present study, we investigated the transcriptional machinery and signaling pathway regulating shear-induced COX-2 expression in human chondrocytic cells. Deletion and mutation analyses of the human cox-2 promoter reveal that the CCAAT/enhancer-binding protein (C/EBP) and activator protein-1 (AP-1) predominantly contribute to the shear-induced cox-2 promoter activity. Supershift assays disclose that C/EBPβ, but not C/EBPα or C/EBPδ, binds to the C/EBP site, whereas c-Jun binds to AP-1. Individual gene knockdown experiments demonstrate the direct regulation of C/EBPβ expression by c-Jun, and the critical roles of both c-Jun and C/EBPβ in shear-induced COX-2 synthesis. Our studies also indicate that Rac and, to a lesser extent, Cdc42 transactivate MEKK1, which is, in turn, responsible for activation of mitogen-activated protein kinase kinase 7 (MKK7). MKK7 regulates c-Jun NH2-terminal kinase 2 activation, which, in turn, triggers the phosphorylation of c-Jun that controls shear-mediated COX-2 upregulation in chondrocytes. Reconstructing the signaling network regulating shear-induced COX-2 expression and inflammation may provide insights to optimize conditions for culturing artificial cartilage in bioreactors and for developing therapeutic interventions for arthritic disorders.
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11
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Habib A, Hamade E, Mahfouz R, Nasrallah MS, de Thé H, Bazarbachi A. Arsenic trioxide inhibits ATRA-induced prostaglandin E2 and cyclooxygenase-1 in NB4 cells, a model of acute promyelocytic leukemia. Leukemia 2008; 22:1125-30. [PMID: 18354491 DOI: 10.1038/leu.2008.59] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In acute promyelocytic leukemia (APL), all-trans retinoic acid (ATRA) triggers cell differentiation, while arsenic trioxide (As(2)O(3)) generates partial differentiation and apoptosis. Animal and human studies suggest that newly diagnosed APL patients can be cured using As(2)O(3) combined with ATRA. Cyclooxygenases are involved in prostaglandins and thromboxane synthesis. We have recently demonstrated that ATRA induces cyclooxygenase-1 (COX-1) expression and prostaglandin synthesis in NB4 cells and in blasts from patients with APL. In the present study we investigated the effect of ATRA and As(2)O(3) co-treatment on COX-1 expression and prostaglandin formation and tested the effect of the COX-1/COX-2 nonselective inhibitor indomethacin on cell differentiation. Arsenic treatment of NB4 cells resulted in a partial but significant reduction of ATRA-dependent induction of COX-1 expression and activity. Pretreatment of NB4 cells with indomethacin significantly impaired ATRA/As(2)O(3)-induced differentiation, as assessed by cell morphology, nitroblue tetrazolium test or CD11c expression. PGE(2) reversed the negative effect of indomethacin on differentiation of ATRA/As(2)O(3)-treated NB4 cells. In conclusion, COX-1 contributes to ATRA-dependent maturation of NB4 cells and is affected by As(2)O(3). These results also suggest that nonsteroidal antiinflammatory drugs should be avoided in APL patients treated with the combination of ATRA and As(2)O(3).
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Affiliation(s)
- A Habib
- Department of Biochemistry, American University of Beirut, Beirut, Lebanon.
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12
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Mbonye UR, Yuan C, Harris CE, Sidhu RS, Song I, Arakawa T, Smith WL. Two distinct pathways for cyclooxygenase-2 protein degradation. J Biol Chem 2008; 283:8611-23. [PMID: 18203712 DOI: 10.1074/jbc.m710137200] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Cyclooxygenases (COX-1 and COX-2) are N-glycosylated, endoplasmic reticulum-resident, integral membrane proteins that catalyze the committed step in prostanoid synthesis. COX-1 is constitutively expressed in many types of cells, whereas COX-2 is usually expressed inducibly and transiently. The control of COX-2 protein expression occurs at several levels, and overexpression of COX-2 is associated with pathologies such as colon cancer. Here we have investigated COX-2 protein degradation and demonstrate that it can occur through two independent pathways. One pathway is initiated by post-translational N-glycosylation at Asn-594. The N-glycosyl group is then processed, and the protein is translocated to the cytoplasm, where it undergoes proteasomal degradation. We provide evidence from site-directed mutagenesis that a 27-amino acid instability motif (27-IM) regulates posttranslational N-glycosylation of Asn-594. This motif begins with Glu-586 8 residues upstream of the N-glycosylation site and ends with Lys-612 near the C terminus at Leu-618. Key elements of the 27-IM include a helix involving residues Glu-586 to Ser-596 with Asn-594 near the end of this helix and residues Leu-610 and Leu-611, which are located in an apparently unstructured downstream region of the 27-IM. The last 16 residues of the 27-IM, including Leu-610 and Leu-611, appear to promote N-glycosylation of Asn-594 perhaps by causing this residue to become exposed to appropriate glycosyl transferases. A second pathway for COX-2 protein degradation is initiated by substrate-dependent suicide inactivation. Suicide-inactivated protein is then degraded. The biochemical steps have not been resolved, but substrate-dependent degradation is not inhibited by proteasome inhibitors or inhibitors of lysosomal proteases. The pathway involving the 27-IM occurs at a constant rate, whereas degradation through the substrate-dependent process is coupled to the rate of substrate turnover.
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Affiliation(s)
- Uri R Mbonye
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
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13
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Deng WG, Montero AJ, Wu KK. Interferon-gamma suppresses cyclooxygenase-2 promoter activity by inhibiting C-Jun and C/EBPbeta binding. Arterioscler Thromb Vasc Biol 2007; 27:1752-9. [PMID: 17556653 DOI: 10.1161/atvbaha.107.144352] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Cyclooxygenase-2 (COX-2) and interferon gamma (IFNgamma) are overexpressed in vascular inflammatory and atherosclerotic lesions. We postulated that IFNgamma suppresses COX-2 expression at the transcriptional level. METHODS AND RESULTS The effect of IFNgamma on COX-2 expression was evaluated in several types of human cells stimulated with phorbol 12-myristate 13-acetate (PMA), interleukin (IL)-1beta, or tumor necrosis factor (TNF) alpha. IFNgamma concentration-dependently inhibited COX-2 proteins and promoter activities induced by PMA or cytokines in human fibroblasts and monocytic and endothelial cells. PMA and cytokines stimulate binding of C-Jun, C-Fos, CCAAT/enhancer binding protein beta (C/EBPbeta), or NF-kappaB to their respective regulatory elements on COX-2 promoter. IFNgamma blocked C-Jun and C/EBPbeta but not C-Fos or p50 NF-kappaB binding as determined by in vitro binding assays and chromatin immunoprecipitation assay. p300 binding to COX-2 promoter was inhibited by IFNgamma in a manner comparable to C-Jun and C/EBPbeta binding. CONCLUSIONS IFNgamma suppresses proinflammatory mediator-induced COX-2 transcription by selective inhibition of C-Jun and C/EBPbeta DNA binding activity and p300 recruitment in human cells. Because IFNgamma is coexpressed with COX-2 in vascular lesions, it may play a role in controlling COX-2-mediated inflammatory changes.
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Affiliation(s)
- Wu-Guo Deng
- University of Texas Health Science Center, Houston, TX 77030-1503, USA
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14
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Bunimov N, Smith JE, Gosselin D, Laneuville O. Translational regulation of PGHS-1 mRNA: 5′ untranslated region and first two exons conferring negative regulation. ACTA ACUST UNITED AC 2007; 1769:92-105. [PMID: 17320986 DOI: 10.1016/j.bbaexp.2007.01.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2006] [Revised: 12/11/2006] [Accepted: 01/17/2007] [Indexed: 11/30/2022]
Abstract
Prostaglandin endoperoxide H synthase-1 gene expression is described as inducible in a few contexts such as differentiation of megakaryoblastic MEG-01 cells into platelet-like structures. In the MEG-01 cells model of PGHS-1 gene induction, we previously reported a delay in protein synthesis and identified the translational step of gene expression as being regulated. In the current study, we mapped PGHS-1 mRNA sequences regulating translational efficiency and identified an RNA binding protein. The 5'UTR and first two exons of the PGHS-1 5' mRNA decreased the synthesis of Luciferase protein by approximately 80% without significant changes in mRNA levels when compared to controls. Both the PGHS-1 5'-UTR and the first two exons were required for activity. Sucrose density gradient fractionations of cytoplasmic extracts from MEG-01 cells infected with reporter constructs, either controls or containing PGHS-1 sequence, presented a similar profile of distribution of reporter transcripts between polysomal and non-polysomal fractions. RNA/protein interaction studies revealed nucleolin binding to the 135 nt PGHS-1 sequence. Mutation of the two NRE elements located in the 5'end of PGHS-1 mRNA sequence partially reduced the negative activity of the 135 nt sequence. Stable secondary structures predicted at the 5' end of the transcript are potentially involved in translational regulation. We propose that the 5'end of PGHS-1 mRNA represses translation and could delay the synthesis of PGHS-1 enzyme.
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Affiliation(s)
- Natalia Bunimov
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, 451 Smyth Road, Ottawa, Ontario, Canada K1H 8M5
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15
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Kang YJ, Mbonye UR, DeLong CJ, Wada M, Smith WL. Regulation of intracellular cyclooxygenase levels by gene transcription and protein degradation. Prog Lipid Res 2007; 46:108-25. [PMID: 17316818 PMCID: PMC3253738 DOI: 10.1016/j.plipres.2007.01.001] [Citation(s) in RCA: 229] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cyclooxygenases-1 and -2 (COX-1 and -2) catalyze the committed step in prostaglandin formation. Each isozyme subserves different biological functions. This is, at least in part, a consequence of differences in patterns of COX-1 and COX-2 expression. COX-1 is induced during development, and COX-1 mRNA and COX-1 protein are very stable. These latter properties can explain why COX-1 protein levels usually remain constant in those cells that express this isozyme. COX-2 is usually expressed inducibly in association with cell replication or differentiation. Both COX-2 mRNA and COX-2 protein have short half-lives relative to those of COX-1. Therefore, COX-2 protein is typically present for only a few hours after its synthesis. Here we review and develop the concepts that (a) COX-2 gene transcription can involve at least six different cis-acting promoter elements interacting with trans-acting factors generated by multiple, different signaling pathways, (b) the relative contribution of each cis-acting COX-2 promoter element depends on the cell type, the stimulus and the time following the stimulus and (c) a unique 27 amino acid instability element located just upstream of the C-terminus of COX-2 targets this isoform to the ER-associated degradation system and proteolysis by the cytosolic 26S proteasome.
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Affiliation(s)
- Yeon-Joo Kang
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Uri R. Mbonye
- Department of Biochemistry and Molecular Biology, Michigan State University, MI 48824
| | - Cynthia J. DeLong
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Masayuki Wada
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - William L. Smith
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109
- To whom correspondence should be addressed: William L. Smith, 1150 W. Medical Center Drive, 5301 Medical Science Research Building III, Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109; Tel: 734-647-6180; Fax:734-764-3509;
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16
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Hewett SJ, Bell SC, Hewett JA. Contributions of cyclooxygenase-2 to neuroplasticity and neuropathology of the central nervous system. Pharmacol Ther 2006; 112:335-57. [PMID: 16750270 DOI: 10.1016/j.pharmthera.2005.04.011] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2005] [Accepted: 04/19/2005] [Indexed: 01/08/2023]
Abstract
Cyclooxygenase (COX) enzymes, or prostaglandin-endoperoxide synthases (PTGS), are heme-containing bis-oxygenases that catalyze the first committed reaction in metabolism of arachidonic acid (AA) to the potent lipid mediators, prostanoids and thromboxanes. Two isozymes of COX enzymes (COX-1 and COX-2) have been identified to date. This review will focus specifically on the neurobiological and neuropathological consequences of AA metabolism via the COX-2 pathway and discuss the potential therapeutic benefit of COX-2 inhibition in the setting of neurological disease. However, given the controversy surrounding the use of COX-2 selective inhibitors with respect to cardiovascular health, it will be important to move beyond COX to identify which down-stream effectors are responsible for the deleterious and/or potentially protective effects of COX-2 activation in the setting of neurological disease. Important advances toward this goal are highlighted herein. Identification of unique effectors in AA metabolism could direct the development of new therapeutics holding significant promise for the prevention and treatment of neurological disorders.
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Affiliation(s)
- Sandra J Hewett
- Department of Neuroscience MC3401, University of Connecticut Health Center, 263 Farmington Avenue, Farmington, CT 06030, USA.
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17
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Hewett SJ, Silakova JM, Hewett JA. Oral treatment with rofecoxib reduces hippocampal excitotoxic neurodegeneration. J Pharmacol Exp Ther 2006; 319:1219-24. [PMID: 16963621 DOI: 10.1124/jpet.106.109876] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The purpose of this study was to determine whether the selective cyclooxygenase-2 (COX-2) inhibitor rofecoxib [4-[4-(methylsulfonyl)phenyl]-3-phenyl-2(5H)-furanone] could effectively prevent hippocampal neuronal injury in an animal model of excitotoxic neurodegeneration. COX-2 protein levels increased between 3 and 6 h, peaked at 12 h, and declined to near baseline levels 24 h after injection of N-methyl-d-aspartate (NMDA; 18 nmol) into the CA1 region of the left hippocampus. Mice that were fed ad libitum a control rodent diet for 4 days before and 3 days after injection of NMDA demonstrated marked neuronal loss in the primary cell layers of the ipsilateral CA1, CA3, and dentate gyrus (50, 30, and 20% cell loss, respectively). This injury was potently and dose-dependently reduced by feeding animals a diet standardized to deliver 15 or 30 mg/kg rofecoxib per day. Neurodegeneration in the CA1 region was reduced by 30.1 +/- 5.6 and 51.5 +/- 9.0%, respectively; in the CA3 by 64.6 +/- 12.4 and 69.0 +/- 14.1%, respectively; and in the dentate gyrus by 47.8 +/- 15.2 and 58.0 +/- 18.2%, respectively. Moreover, rofecoxib chow slightly but significantly reduced injury-induced brain edema. These findings demonstrate that rofecoxib can ameliorate excitotoxic neuronal injury in vivo and, as such, may be a particularly promising pharmaceutical for the treatment of neurological diseases associated with overactivation of NMDA receptors.
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Affiliation(s)
- Sandra J Hewett
- Department of Neuroscience, Program in Cellular and Molecular Pharmacology, University of Connecticut School of Medicine, Farmington, Connecticut, USA.
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18
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Kaul R, Verma SC, Murakami M, Lan K, Choudhuri T, Robertson ES. Epstein-Barr virus protein can upregulate cyclo-oxygenase-2 expression through association with the suppressor of metastasis Nm23-H1. J Virol 2006; 80:1321-31. [PMID: 16415009 PMCID: PMC1346972 DOI: 10.1128/jvi.80.3.1321-1331.2006] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Previous studies have demonstrated the interaction between the Epstein-Barr virus (EBV) nuclear antigen 3C (EBNA3C) and the metastatic suppressor Nm23-H1 both in vitro and in vivo (C. Subramanian, M. A. Cotter II, and E. S. Robertson, Nat. Med. 7:350-355, 2001). EBNA3C can reverse the ability of Nm23-H1 to suppress migration of Burkitt's lymphoma and breast carcinoma cell lines in vitro. EBNA3C contributes to EBV-associated human cancers by regulating transcription of a number of cellular and viral promoters and by targeting and altering the transcription activities of the metastasis suppressor Nm23-H1. Cyclo-oxygenase-2 (COX-2), an inducible enzyme important in inflammation, is overexpressed in a variety of cancers and can influence cell migration. In this report we show that Nm23-H1 and EBNA3C can modulate expression of COX-2 in the context of EBV infection and transformation. The levels of COX-2 were consistently higher in EBV-positive cells than in EBV-negative cells. Additionally, we show that Nm23-H1 can upregulate the COX-2 promoter element in luciferase reporter assays, whereas EBNA3C alone did not affect the level of response but clearly contributed to an additive increase when coexpressed with Nm23-H1. The downstream effect of COX-2 expression was also evaluated and showed that prostaglandin E(2) levels increased with Nm23-H1 and that there was some level of cooperativity in the presence of EBNA3C. The majority of this response was mediated through the cyclic AMP response element and NF-kappaB sites. These studies suggest a potential role for COX-2 in EBV-associated human cancers.
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MESH Headings
- Antigens, Viral/genetics
- Antigens, Viral/physiology
- Base Sequence
- Binding Sites/genetics
- Cell Line
- Cell Line, Tumor
- Cell Transformation, Viral
- Cyclooxygenase 2/genetics
- DNA, Complementary/genetics
- Epstein-Barr Virus Infections/genetics
- Epstein-Barr Virus Infections/physiopathology
- Epstein-Barr Virus Infections/virology
- Epstein-Barr Virus Nuclear Antigens
- Herpesvirus 4, Human/genetics
- Herpesvirus 4, Human/pathogenicity
- Herpesvirus 4, Human/physiology
- Humans
- Models, Biological
- NF-kappa B/metabolism
- NM23 Nucleoside Diphosphate Kinases
- Neoplasm Metastasis
- Nucleoside-Diphosphate Kinase/physiology
- Promoter Regions, Genetic
- Recombinant Proteins/genetics
- Recombinant Proteins/metabolism
- Transfection
- Up-Regulation
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Affiliation(s)
- Rajeev Kaul
- Department of Microbiology, University of Pennsylvania School of Medicine, 201E Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA 19104, USA
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19
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DeLong CJ, Smith WL. An intronic enhancer regulates cyclooxygenase-1 gene expression. Biochem Biophys Res Commun 2005; 338:53-61. [PMID: 16105649 DOI: 10.1016/j.bbrc.2005.07.184] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2005] [Accepted: 07/30/2005] [Indexed: 11/20/2022]
Abstract
To identify cis-elements regulating PMA-induced prostaglandin H synthase-1 (PGHS-1) gene expression in the human megakaryoblast cell line, MEG-01, we performed promoter reporter assays with a luciferase reporter vector containing the -2030/-22 region of the human PGHS-1 gene. PMA treatment for 24 h increased PGHS-1 promoter activity by twofold. Mutagenesis studies of the promoter revealed a single Sp1 site essential for PMA-inducible transcription. Insertion of a highly conserved 100 bp sequence cloned from intron 8 into the -2030/-22 reporter plasmid enhanced PMA-dependent transcription 10-fold. Mutation of either a consensus AP-1 site within intron 8 or the Sp1 site in the promoter reduced PMA-induced activity by 80-100%. Gel shift assays using the intron 8 AP-1 sequence demonstrated the formation of an AP-1-specific DNA-protein complex. Our results suggest that inducible PGHS-1 gene expression involves the coordinate functioning of a Sp1 site in the promoter and an AP-1 site in intron 8.
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Affiliation(s)
- Cynthia J DeLong
- Department of Biological Chemistry, University of Michigan Medical School, 5416 Medical Science I, 1301 Catherine St., Ann Arbor, MI 48109-0606, USA
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20
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Park SW, Sung MW, Heo DS, Inoue H, Shim SH, Kim KH. Nitric oxide upregulates the cyclooxygenase-2 expression through the cAMP-response element in its promoter in several cancer cell lines. Oncogene 2005; 24:6689-98. [PMID: 16007171 DOI: 10.1038/sj.onc.1208816] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
We previously showed that nitric oxide (NO) induces overexpression of cyclooxygenase-2 (COX-2) and production of prostaglandin E(2) in cancer cells. Here, we investigated the mechanisms by which NO induces COX-2 expression in cancer cells. We found that the cAMP-response element (CRE) is a critical factor in NO-induced COX-2 expression in all cells tested. We found that in cancer cells, three transcription factors (TFs) - cAMP response element-binding protein (CREB), activating transcription factor-2 (ATF-2) and c-jun, bound the CRE in the COX-2 promoter, and their activities were increased by addition of the NO donor, S-nitroso-N-acetyl-D,L-penicillamine (SNAP). NO-induced activation of soluble guanylate cyclase (sGC), p38 and c-Jun NH(2)-terminal kinase (JNK) upregulated the three TFs, leading to COX-2 overexpression. Addition of dibutyryl-cGMP (db-cGMP) induced COX-2 expression in a manner similar to SNAP; this induction was blocked by a p38 inhibitor (SB202190), but not by a JNK inhibitor (SP600125). NO-induced cGMP was found to activate CREB and ATF-2 in a p38, but not c-jun-dependent manner, while NO induced JNK in a cGMP-independent manner, leading to subsequent activation of c-jun and ATF-2. These results suggest that the low concentrations of endogenous NO present in cancer cell may induce the expression of many genes, including COX-2, which promotes the growth and survival of tumor cells.
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Affiliation(s)
- Seok-Woo Park
- Department of Tumor Biology, College of Medicine, Seoul National University, Chongno-gu, Korea
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21
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Korita D, Itoh H, Sagawa N, Yura S, Yoshida M, Kakui K, Takemura M, Fujii S. 17beta-estradiol up-regulates prostacyclin production in cultured human uterine myometrial cells via augmentation of both cyclooxygenase-1 and prostacyclin synthase expression. ACTA ACUST UNITED AC 2005; 11:457-64. [PMID: 15458742 DOI: 10.1016/j.jsgi.2004.04.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
OBJECTIVE To investigate whether 17beta-estradiol elevates prostacyclin (PGI(2)) production in human myometrial cells in the middle of gestation. METHODS The concentration of 6-keto-PGF(1alpha), a stable metabolite of PGI(2), in the culture medium was assessed using enzyme-linked immunosorbent assay (ELISA). Western blot analysis and quantitative reverse-transcriptase polymerase chain reaction (RT-PCR) using TaqMan (Applied Biosystems, Foster City, CA) technology were performed to evaluate the expression of cytosolic phopholipase A(2) (cPLA(2)), cyclooxygenase-1 (COX-1), COX-2, and prostacyclin synthase (PGIS) in cultured human myometrial cells prepared from second trimester pregnant women (n = 3) after stimulation with 17beta-estradiol. RESULTS Treatment with 17beta-estradiol (4-400 nM) dose-dependently elevated PGI(2) secretion from cultured human myometrial cells. Western blot analysis detected cPLA(2) and COX-1 and PGIS protein expression in the cultured human myometrial cells; however, COX-2 protein expression was below the detection sensitivity. Stimulation with 40-nM 17beta-estradiol significantly up-regulated protein and mRNA expression of both COX-1 and PGIS. CONCLUSION 17beta-Estradiol from placenta may contribute to the augmentation of PGI(2) production in the human myometrium in the middle of gestation via up-regulation of both COX-1 and PGIS expression.
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Affiliation(s)
- Daizo Korita
- Department of Gynecology and Obstetrics, Kyoto University Graduate School of Medicine, Kyoto, Japan
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22
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Gibson LL, Hahner L, Osborne-Lawrence S, German Z, Wu KK, Chambliss KL, Shaul PW. Molecular basis of estrogen-induced cyclooxygenase type 1 upregulation in endothelial cells. Circ Res 2005; 96:518-25. [PMID: 15705965 DOI: 10.1161/01.res.0000158967.96231.88] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Estrogen upregulates cyclooxygenase-1 (COX-1) expression in endothelial cells. To determine the basis of this process, studies were performed in ovine endothelial cells transfected with the human COX-1 promoter fused to luciferase. Estradiol (E2) caused activation of the COX-1 promoter with maximal stimulation at 10(-8) mol/L E2, and the response was mediated by either ERalpha or ERbeta. Mutagenesis revealed a primary role for a putative Sp1 binding motif at -89 (relative to the ATG codon) and lesser involvement of a consensus Sp1 site at -111. Electrophoretic mobility shift assays yielded a single complex with the site at -89, and supershift analyses implicated AP-2alpha and ERalpha, and not Sp1, in protein-DNA complex formation. In endothelial cells with minimal endogenous ER, the transfection of ERalpha mutants lacking the DNA binding domain or primary nuclear localization signals caused 4-fold greater stimulation of promoter activity with E2 than wild-type ERalpha. In contrast, mutant ERalpha lacking the A-B domains was inactive. Thus, estrogen-mediated upregulation of COX-1 in endothelium is uniquely independent of direct ERalpha-DNA binding and instead entails protein-DNA interaction involving AP-2alpha and ERalpha at a proximal regulatory element. In addition, the process may be initiated by cytoplasmic ERalpha, and critical receptor elements reside within the amino terminus.
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Affiliation(s)
- Linda L Gibson
- Department of Pediatrics, University of Texas Southwestern Medical Center at Dallas, TX 75390, USA
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23
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Deng WG, Zhu Y, Montero A, Wu KK. Quantitative analysis of binding of transcription factor complex to biotinylated DNA probe by a streptavidin-agarose pulldown assay. Anal Biochem 2004; 323:12-8. [PMID: 14622953 DOI: 10.1016/j.ab.2003.08.007] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Gene expression is regulated by a large complex of proteins that bind to the promoter/enhancer region of a gene. We determined whether a streptavidin-bead binding assay might be useful in detecting individual proteins in the complex comprising transactivators, coactivators, mediators, and general transcription factors. We used biotinylated cyclooxygenase-2 promoter probes as a model. Nuclear extracts obtained from human fibroblasts treated with or without an agonist were incubated with a 5(')-biotinylated probe and streptavidin-agarose beads at room temperature for 1h. After centrifugation, the pellet was washed and proteins in the complex were assessed by immunoblots. An array of transcription factors was detectable concurrently in the same batch of pellets at basal state. p300 and its associated factor PCAF levels but not Srb7, Med7, or TFII(B) were increased by phorbol ester or tumor necrosis factor alpha stimulation. Only trace of CREB-binding protein was detected. These results suggest that p300 and PCAF are the predominant coactivators for COX-2 promoter activation. Our findings indicate that the streptavidin-bead pulldown assay is valuable for determining the binding of a large number of transcription factors to promoter/enhancer and evaluating the relationship of protein binding with regulation of gene expression.
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Affiliation(s)
- Wu-Guo Deng
- University of Texas-Houston Medical School, University of Texas Health Science Center, 6431 Fannin, MSB 5.016, Houston, TX 95616, USA
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24
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Rocca B, Morosetti R, Habib A, Maggiano N, Zassadowski F, Ciabattoni G, Chomienne C, Papp B, Ranelletti FO. Cyclooxygenase-1, but not -2, is upregulated in NB4 leukemic cells and human primary promyelocytic blasts during differentiation. Leukemia 2004; 18:1373-9. [PMID: 15190260 DOI: 10.1038/sj.leu.2403407] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Cyclooxygenase (COX)-1 or -2 and specific prostaglandin (PG) synthases catalyze the formation of various PGs. We investigated the expression and activity of COX-1 and -2 during granulocyte-oriented maturation induced by all-trans-retinoic acid (ATRA) of NB4 cells, originated from a human acute promyelocytic leukemia (APL), and in blasts from APL patients. The expression of COX isoenzymes or prostaglandin synthases was also investigated in circulating granulocytes and human bone marrow. COX-1 was expressed and enzymatically active in NB4 cells and primary blasts. COX-1 mRNA and protein were induced by ATRA. COX-1 protein increased approximately 2-3.5-fold by culture day 3 in NB4 cells and primary blasts, while basal COX-2 expression was very low and unaffected by ATRA. COX-1-dependent PGE(2) biosynthesis increased during differentiation approx. 5-fold. Indomethacin and the selective COX-1 inhibitor SC-560, but not selective COX-2 inhibition, impaired NB4 differentiation, reducing NADPH-oxidase activity, CD11b and CD11c expression. The immunohistochemistry of granulocytes and myeloid precursors in the bone marrow showed a large prevalence of COX-1 as compared to COX-2. In conclusion, COX-1 is induced during ATRA-dependent maturation and appears to contribute to myeloid differentiation both in vitro and ex vivo, and COX-1 activity may potentiate the differentiation of human APL.Leukemia (2004) 18, 1373-1379. doi:10.1038/sj.leu.2403407 Published online 10 June 2004
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Affiliation(s)
- B Rocca
- Department of Internal Medicine, Catholic University School of Medicine, Rome, Italy.
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25
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Long JA, Fogel-Petrovic M, Knight DA, Thompson PJ, Upham JW. Higher prostaglandin e2 production by dendritic cells from subjects with asthma compared with normal subjects. Am J Respir Crit Care Med 2004; 170:485-91. [PMID: 15151923 DOI: 10.1164/rccm.200311-1595oc] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Dendritic cells (DCs) are thought to play an important role in the pathogenesis of allergic disorders through their ability to interact with T cells to initiate and amplify helper T cell Type 2 immune responses. The mechanisms by which this occurs are not completely understood, nor is it clear whether DC function differs between normal individuals and individuals with asthma. We compared the function of DCs from 10 subjects with allergic asthma and 10 normal individuals, focusing on the production of prostaglandin E (PGE) 2, interleukin (IL)-10, and IL-12 p70, mediators that play an important role in helper T cell Type 1/Type 2 polarization. Monocyte-derived DCs were established by culturing monocytes with granulocyte-macrophage colony-stimulating factor and IL-4 for 7 days, and then stimulated with LPS plus IFN-gamma. PGE2, IL-10, and IL-12 production was evaluated by ELISA, whereas cyclooxygenase-1, and -2 messenger RNA expression was analyzed using reverse transcription-polymerase chain reaction. LPS-stimulated monocyte-derived DCs from individuals with asthma exhibited increased PGE2 and IL-10 production, but equivalent IL-12 p70 synthesis, when compared with DCs from normal subjects. Increased PGE2 synthesis by DCs from subjects with asthma was associated with an increase in cyclooxygenase-2 messenger RNA expression. These findings support the notion that DC function is significantly altered in allergic asthma.
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Affiliation(s)
- Julie A Long
- Asthma and Allergy Research Institute, University of Western Australia, West Perth, WA, Australia
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26
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Martel-Pelletier J, Pelletier JP, Fahmi H. Cyclooxygenase-2 and prostaglandins in articular tissues. Semin Arthritis Rheum 2004; 33:155-67. [PMID: 14671726 DOI: 10.1016/s0049-0172(03)00134-3] [Citation(s) in RCA: 230] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
OBJECTIVES To provide an overview on: 1) the expression of cyclooxygenase (COX)-2 in articular tissues; 2) the role of prostaglandin E2 (PGE2) in these tissue functions; and 3) clinical trials with COX-2-selective nonsteroidal anti-inflammatory drugs (NSAIDs) (coxibs). METHODS MEDLINE search was performed using the key words "cyclooxygenase," "prostaglandin," "osteoarthritis" (OA), and "rheumatoid arthritis" (RA). Selected publications related to clinical trials with coxibs also are included. RESULTS COX-2 is upregulated in inflamed joint tissues and is responsible for elevated PGE2 production. The overexpression of COX-2 is likely induced by proinflammatory mediators such as interleukin-1beta (IL-1beta) and tumor necrosis factor (TNF) alpha. However, the exact molecular mechanisms through which the expression of COX-2 is regulated remain to be elucidated. Several studies suggest that PGE2 is involved in inflammation, apoptosis, angiogenesis, and possibly structural changes that characterize arthritic diseases. NSAIDs are prescribed for the treatment of OA and RA and provide effective relief from symptoms; however, serious gastrointestinal complications occur with their use. The clinical efficacy of NSAIDs is primarily related to the inhibition of COX-2, whereas much of the toxicity is related to COX-1 inhibition. Selective COX-2 inhibitors (coxibs) that spare COX-1 at therapeutic doses are more effective than placebo and as effective as other NSAIDs for relief of symptoms of OA and RA, and have significantly improved gastrointestinal safety and tolerability. However, some studies showed that COX-2-selective inhibitors still have classic NSAID complications. CONCLUSIONS Overexpression of COX-2 protein in articular tissues is a characteristic feature of arthritic diseases. However, the molecular mechanisms involved in the regulation of COX-2 expression and activity are still unclear. Elucidating the mechanisms of COX-2 expression and PGE2 production and action will help identify novel and more selective potential drug targets in the treatment of arthritic diseases.
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Affiliation(s)
- Johanne Martel-Pelletier
- Osteoarthritis Research Unit, Centre Hospitalier de l'Université de Montréal, Hôpital Notre-Dame, Quebec, Canada
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Grossman CE, Qian Y, Banki K, Perl A. ZNF143 mediates basal and tissue-specific expression of human transaldolase. J Biol Chem 2003; 279:12190-205. [PMID: 14702349 DOI: 10.1074/jbc.m307039200] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Transaldolase regulates redox-dependent apoptosis through controlling NADPH and ribose 5-phosphate production via the pentose phosphate pathway. The minimal promoter sufficient to drive chloramphenicol acetyltransferase reporter gene activity was mapped to nucleotides -49 to -1 relative to the transcription start site of the human transaldolase gene. DNase I footprinting with nuclear extracts of transaldolase-expressing cell lines unveiled protection of nucleotides -29 to -16. Electrophoretic mobility shift assays identified a single dominant DNA-protein complex that was abolished by consensus sequence for transcription factor ZNF143/76 or mutation of the ZNF76/143 motif within the transaldolase promoter. Mutation of an AP-2alpha recognition sequence, partially overlapping the ZNF143 motif, increased TAL-H promoter activity in HeLa cells, without significant impact on HepG2 cells, which do not express AP-2alpha. Cooperativity of ZNF143 with AP-2alpha was supported by supershift analysis of HeLa cells where AP-2 may act as cell type-specific repressor of TAL promoter activity. However, overexpression of full-length ZNF143, ZNF76, or dominant-negative DNA-binding domain of ZNF143 enhanced, maintained, or abolished transaldolase promoter activity, respectively, in HepG2 and HeLa cells, suggesting that ZNF143 initiates transcription from the transaldolase core promoter. ZNF143 overexpression also increased transaldolase enzyme activity. ZNF143 and transaldolase expression correlated in 21 different human tissues and were coordinately upregulated 14- and 34-fold, respectively, in lactating mammary glands compared with nonlactating ones. Chromatin immunoprecipitation studies confirm that ZNF143/73 associates with the transaldolase promoter in vivo. Thus, ZNF143 plays a key role in basal and tissue-specific expression of transaldolase and regulation of the metabolic network controlling cell survival and differentiation.
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Affiliation(s)
- Craig E Grossman
- Department of Medicine, State University of New York, Upstate Medical University, College of Medicine, 750 East Adams Street, Syracuse, NY 13210, USA
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28
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Ghannam G, Takeda A, Camarata T, Moore MA, Viale A, Yaseen NR. The oncogene Nup98-HOXA9 induces gene transcription in myeloid cells. J Biol Chem 2003; 279:866-75. [PMID: 14561764 DOI: 10.1074/jbc.m307280200] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The nucleoporin Nup98 gene is frequently rearranged in acute myelogenous leukemia (AML). In most cases this results in fusion of the N terminus of Nup98 to the DNA binding domain of a homeodomain transcription factor. The prototype of these fusions, Nup98-HOXA9, is associated with human AML and induces AML in mouse models. To understand the mechanisms by which Nup98-HOXA9 causes AML, we expressed it in myeloid cells and identified its target genes using high density oligonucleotide microarrays. The analysis was performed in triplicate and was confirmed by quantitative real time PCR. Of the 102 Nup98-HOXA9 target genes identified, 92 were up-regulated, and only 10 were down-regulated, suggesting a transcriptional activation function. A similar analysis of wild-type HOXA9 revealed 13 target genes, 12 of which were up-regulated, and 1 was down-regulated. In contrast, wild-type Nup98 had no effect on gene expression, demonstrating that the HOXA9 DNA binding domain is required for gene regulation. Co-transfection experiments using a luciferase reporter linked to the promoter of one of the Nup98-HOXA9 target genes confirmed up-regulation at the transcriptional level by Nup98-HOXA9 but not by either HOXA9 or Nup98. These data indicate that Nup98-HOXA9 is an aberrant transcription factor whose activity depends on the HOXA9 DNA binding domain but has a stronger and wider transcriptional effect than HOXA9. Several of the genes regulated by Nup98-HOXA9 are associated with increased cell proliferation and survival as well as drug metabolism, providing insights into the pathogenesis and epidemiology of Nup98-HOXA9-induced AML.
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MESH Headings
- Animals
- Blotting, Western
- Cell Cycle
- Cell Division
- Cell Survival
- Down-Regulation
- Flow Cytometry
- Gene Expression Regulation, Neoplastic
- Genes, Reporter
- Green Fluorescent Proteins
- Homeodomain Proteins/physiology
- Humans
- Image Processing, Computer-Assisted
- K562 Cells
- Leukemia, Myeloid, Acute/drug therapy
- Leukemia, Myeloid, Acute/metabolism
- Luciferases/metabolism
- Luminescent Proteins/metabolism
- Mice
- Models, Biological
- Myeloid Cells/metabolism
- Nuclear Pore Complex Proteins/physiology
- Oligonucleotide Array Sequence Analysis
- Oncogene Proteins, Fusion/physiology
- Plasmids/metabolism
- Protein Structure, Tertiary
- Retroviridae/genetics
- Reverse Transcriptase Polymerase Chain Reaction
- Transcription, Genetic
- Transcriptional Activation
- Transfection
- Up-Regulation
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Affiliation(s)
- Ghada Ghannam
- Department of Pathology, The Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
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29
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Ohkawara S, Yokoyama C, Shimonishi M, Tanabe T. Analysis of the transcriptional regulation of mouse prostacyclin synthase gene. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2003; 507:281-6. [PMID: 12664598 DOI: 10.1007/978-1-4615-0193-0_43] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
MESH Headings
- 5' Untranslated Regions/genetics
- Animals
- Aorta
- Binding Sites
- Cattle
- Cells, Cultured
- Cloning, Molecular
- Cytochrome P-450 Enzyme System/genetics
- Cytochrome P-450 Enzyme System/metabolism
- Endothelium, Vascular/cytology
- Endothelium, Vascular/physiology
- Gene Expression Regulation, Enzymologic
- Intramolecular Oxidoreductases/genetics
- Intramolecular Oxidoreductases/metabolism
- Mice
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/physiology
- Mutagenesis, Site-Directed
- Podophyllin/analogs & derivatives
- Podophyllin/metabolism
- Podophyllotoxin/analogs & derivatives
- Recombinant Proteins/metabolism
- Transcription, Genetic
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Affiliation(s)
- Susumu Ohkawara
- Department of Pharmacology, National Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka 565-8565 Japan
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30
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Duquette M, Laneuville O. Translational regulation of prostaglandin endoperoxide H synthase-1 mRNA in megakaryocytic MEG-01 cells. Specific protein binding to a conserved 20-nucleotide CIS element in the 3'-untranslated region. J Biol Chem 2002; 277:44631-7. [PMID: 12237309 DOI: 10.1074/jbc.m207007200] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Prostaglandin endoperoxide H synthase-1 (PGHS-1) is an abundant enzyme in platelets, where it plays a key role in the cascade of prostanoid formation. In platelets, the primary site of PGHS-1 synthesis is in precursor megakaryocytic cells. We have previously shown that in megakaryocytic MEG-01 cells, TPA induces an increase of PGHS-1 mRNA within a few hours, whereas protein increase occurs after several days of treatment. We now report that the delayed increase in PGHS-1 protein is caused by translational regulation. De novo PGHS-1 synthesis, measured using [(35)S]methionine pulse labeling followed by immunoprecipitation, was detected at day 4 after TPA treatment but not at day 1. To identify a potential element of PGHS-1 mRNA controlling translation, we compared the 3'-untranslated region from different species and identified a 20-nt segment perfectly conserved. The 20-nt segment was used as a probe in RNA gel mobility-shift assays using MEG-01 extracts from control cells or from TPA-treated cells. Four complexes were formed with extracts from control cells or cells treated with TPA for 1 day but were not observed with extracts from cells treated for 4 days. Of the 4 complexes, one was sequence-specific and binding involved uridylate residues and interactions with a 45-kDa protein and a protein doublet of 116 kDa. Binding of this 45/116-kDa complex to the 20-nt conserved cis element most likely regulates negatively PGHS-1 protein accumulation. We have provided evidence that the PGHS-1 gene is regulated at the translational level.
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Affiliation(s)
- Maryse Duquette
- Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, 451 Smyth Road, Ottawa K1H 8M5, Canada
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31
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Scott BT, Hasstedt SJ, Bovill EG, Callas PW, Valliere JE, Wang L, Wu KK, Long GL. Characterization of the human prostaglandin H synthase 1 gene (PTGS1): exclusion by genetic linkage analysis as a second modifier gene in familial thrombosis. Blood Coagul Fibrinolysis 2002; 13:519-31. [PMID: 12192304 DOI: 10.1097/00001721-200209000-00007] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Genetic evidence from a large Vermont kindred indicates that an unknown gene promotes thrombosis when inherited in conjunction with type I protein C deficiency. Cyclooxygenase-1 [prostaglandin H synthase 1 gene (PTGS1)] was tested as a plausible candidate for the unknown gene because of its role in primary hemostasis. The complete sequence of PTGS1 (25 638 nucleotides) was determined from a 37 kb human genomic cosmid clone to characterize intronic regions and subsequently to allow the search for mutations by direct sequencing of genomic DNA. Northern blot analysis confirms usage of a newly described distal poly-adenylation signal. Short tandem repeat (STR) sequences found in intron 2 and the 3' flanking region were developed as new genetic markers for PTGS1. The position of PTGS1 was refined on the CHLC chromosome 9 linkage map using the new markers scored in four Centre d'Etude du Polymorphisme Humain families and multipoint linkage analysis. Direct sequencing of DNA from members of the Vermont kindred led to the discovery of two new single nucleotide polymorphisms (SNPs) that give rise to non-conservative amino acid changes in the signal peptide (Arg(8) to Trp and Pro(17) to Leu) of cyclooxygenase-1. Linkage analysis of the SNP and STR markers indicated that PTGS1 is not the interacting gene associated with an increased incidence of thrombosis in the Vermont kindred.
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Affiliation(s)
- B T Scott
- Department of Pathology, University of Vermont, Burlington 05405, USA.
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32
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Ye X, Liu SF. Lipopolysaccharide down-regulates Sp1 binding activity by promoting Sp1 protein dephosphorylation and degradation. J Biol Chem 2002; 277:31863-70. [PMID: 12089157 DOI: 10.1074/jbc.m205544200] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We examined the in vivo effect of lipopolysaccharide (LPS) on Sp1 (promoter-selective transcription factor 1) DNA binding activity and studied the mechanisms involved in mouse lungs. The Sp1 DNA complex displayed a major band composed of Sp1, Sp2, and Sp3 trimer and a minor band composed of Sp3 homodimer. Compared with control, nuclear proteins from lungs challenged with LPS for 60, 90, 120, 150, 180, and 240 min, respectively, showed a markedly reduced Sp1 binding activity. Down-regulation of Sp1 binding activity was accompanied by a reduced expression of two Sp1-dependent genes (endothelial nitric oxide synthase and cyclooxygenase-1). Immunoprecipitation-Western blot experiments demonstrated that LPS dephosphorylated Sp1 protein at serine and threonine residues but not at the tyrosine residue. Dephosphorylation of Sp1 protein in vitro significantly reduced Sp1 DNA binding activity. Deglycosylation of Sp1 protein also reduced Sp1 binding activity. However, LPS did not cause Sp1 deglycosylation. LPS markedly reduced nuclear Sp1 protein level but had no significant effect on Sp1 mRNA abundance and on Sp1 protein nuclear translocation. Both Sp1 protein dephosphorylation and Sp1 protein degradation are temporally correlated to the reduced Sp1 binding activity. Our results demonstrate that challenge of mice with LPS in vivo down-regulates Sp1 DNA binding activity through promoting Sp1 protein dephosphorylation and degradation.
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Affiliation(s)
- Xiaobing Ye
- Department of Medicine, Division of Pulmonary and Critical Care Medicine, Long Island Jewish Medical Center, Long Island Campus for the Albert Einstein College of Medicine, New Hyde Park, New York 11040, USA
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33
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Tanabe T, Tohnai N. Cyclooxygenase isozymes and their gene structures and expression. Prostaglandins Other Lipid Mediat 2002; 68-69:95-114. [PMID: 12432912 DOI: 10.1016/s0090-6980(02)00024-2] [Citation(s) in RCA: 287] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The cyclooxygenase (COX, prostaglandin endoperoxide synthase) is a key enzyme in prostaglandin biosynthesis. Two isoforms of COX, COX-1 and COX-2, have been identified by molecular biological methods. The amino acid sequence homology between COX-1 and COX-2 is about 60% for the human enzymes. COX-1 is constitutively expressed in most tissues and cells in animal species. The COX-1 promoter region lacks a canonical TATA or CAAT box and is GC-rich. These features are consistent with those of a housekeeping gene. On the other hand, COX-2 is an inducible enzyme and is induced by various cytokines and mitogenic factors. The induction of COX-2 is suppressed by dexamethasone and PGJ2. There are many consensus cis-elements in the 5'-flanking region to regulate the expression of COX-2. Among them, a CRE, an NF-kappaB site, a NF-IL6 motif and an E-box, regulate transcription independently or synergistically. Most of the transcriptional signaling pathways require activation of the mitogen-activated protein kinase (MAPK) cascade. Moreover, MAPK signaling pathways are involved in regulating COX-2 gene expression at the post-transcriptional level.
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Affiliation(s)
- Tadashi Tanabe
- Department of Pharmacology, National Cardiovascular Center Research Institute, Suita, Osaka, Japan.
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34
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Abstract
The enzymes that convert arachidonic acid to prostaglandin H2 are named cyclooxygenase-1 (COX-1) and COX-2. The properties of COX-1 are different from those of COX-2. It was originally thought that the function of COX-1 was involved in physiological phenomena, whereas that of COX-2 was involved in various pathologies. However, studies with COX-2 knockout mouse suggest that COX-2 also plays important roles in development and homeostasis. This chapter focuses on the distinct functions of COX-1 and COX-2.
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Affiliation(s)
- Ikuo Morita
- Department of Cellular Physiological Chemistry, Graduate School, Tokyo Medical and Dental University, Japan.
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35
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Taniura S, Kamitani H, Watanabe T, Eling TE. Transcriptional regulation of cyclooxygenase-1 by histone deacetylase inhibitors in normal human astrocyte cells. J Biol Chem 2002; 277:16823-30. [PMID: 11877441 DOI: 10.1074/jbc.m200527200] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
While cyclooxygenase (COX)-2 is a highly inducible gene, COX-1 is widely known as a noninducible gene and is constitutively expressed in a variety of cell lines and human tissues. Recently, several reports have indicated that COX-1 is also regulated at the transcriptional level by various stimuli. We present evidence that histone deacetylase (HDAC) inhibitors induce COX-1 transcription and translation in normal human astrocyte (NHA) cells and glioma cell lines. HDAC inhibitors increased acetylated histone H4 protein expression in NHA cells. The levels of COX-1 mRNA and protein were maximal at 24 and 48 h, respectively, after treatment with the specific HDAC inhibitor, trichostatin A (TSA). In addition, TSA-treated NHA cells produced prostaglandin E(2) as determined by enzyme-linked immunosorbent assay after incubation with 10 microm exogenous arachidonic acid, indicating that the induced COX-1 is functionally active. In addition to NHA cells, this up-regulation of COX-1 after treatment with HDAC inhibitors was observed in 5 different glioma cell lines. The nucleotide sequence of the inducible COX-1 cDNA was confirmed identical to human COX-1 that was previously reported. HDAC inhibitors stimulated COX-1 promoter activity as measured by luciferase reporter assays, suggesting that the induction of COX-1 is regulated at the transcriptional level. Furthermore, mutation analysis of the COX-1 promoter suggests that TSA-responsive element exists in the proximal Sp1-binding site at +25 to +31. In conclusion, COX-1 is an inducible gene in glial-derived cells including immortalized cells, and appears to be transcriptionally regulated by a unique mechanism associated with histone acetylation.
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Affiliation(s)
- Seijiro Taniura
- Laboratory of Molecular Carcinogenesis, NIEHS, National Institutes of Health, Research Triangle Park, North Carolina 27709, USA
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36
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Ye X, Liu SF. Lipopolysaccharide regulates constitutive and inducible transcription factor activities differentially in vivo in the rat. Biochem Biophys Res Commun 2001; 288:927-32. [PMID: 11688998 DOI: 10.1006/bbrc.2001.5883] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The pathophysiology of septic shock is characterized by the induction of multiple proinflammatory genes and their products. Transcription factors play key roles in the transcription of these genes. Transcription factors may play important roles in the pathophysiology of septic shock. However, little information is available regarding the in vivo transcription factor activities during sepsis. We have studied the in vivo effects of LPS on the DNA binding activities of transcription factors Sp1 (promoter selective transcription factor), AP-2 (activating protein-2), AP-1 (activating protein-1), NF-kappaB (nuclear factor kappa B), and CREB (cAMP response element binding protein). We found that LPS up-regulated the DNA binding activity of inducible transcription factors AP-1, NF-kappaB, and CREB in a time-dependent manner, but down-regulated the DNA binding activity of constitutive transcription factors Sp1 and AP-2. Thus, LPS regulates the inducible and constitutive transcription factors differentially under in vivo conditions.
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Affiliation(s)
- X Ye
- Division of Pulmonary and Critical Care Medicine, Long Island Campus for the Albert Einstein College of Medicine, New Hyde Park, New York 11040, USA
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37
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Abstract
The prostaglandin endoperoxide H synthases-1 and 2 (PGHS-1 and PGHS-2; also cyclooxygenases-1 and 2, COX-1 and COX-2) catalyze the committed step in prostaglandin synthesis. PGHS-1 and 2 are of particular interest because they are the major targets of nonsteroidal anti-inflammatory drugs (NSAIDs) including aspirin, ibuprofen, and the new COX-2 inhibitors. Inhibition of the PGHSs with NSAIDs acutely reduces inflammation, pain, and fever, and long-term use of these drugs reduces fatal thrombotic events, as well as the development of colon cancer and Alzheimer's disease. In this review, we examine how the structures of these enzymes relate mechanistically to cyclooxygenase and peroxidase catalysis, and how differences in the structure of PGHS-2 confer on this isozyme differential sensitivity to COX-2 inhibitors. We further examine the evidence for independent signaling by PGHS-1 and PGHS-2, and the complex mechanisms for regulation of PGHS-2 gene expression.
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Affiliation(s)
- W L Smith
- Department of Biochemistry, Michigan State University, East Lansing, MI 48824, USA.
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38
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Eykholt RL, Potter S, Marvin KW, Mitchell MD. Transcriptional regulation of prostaglandin-H-synthase-1 in the amnion-derived AV3 cell line. Prostaglandins Other Lipid Mediat 2001; 63:123-31. [PMID: 11204739 DOI: 10.1016/s0090-6980(00)00102-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Prostaglandin-H-synthase-1 (PGHS-1), while constitutively expressed in most tissues, increases in abundance in human gestational membranes at term. This suggests that PGHS-1 may be up-regulated in preparation for labor, and thus might be a key determinant in timing labor onset. We conducted transient transfection experiments in amnion-derived AV3 cells utilizing pPGHS1CAT to identify substances that might regulate PGHS-1 expression in amnion. Transforming growth factor-beta (1 ng/ml) and 15-deoxy-delta(12,14) prostaglandin J2 (1 microM) significantly (P < 0.05) (33% and 44% respectively) increased PGHS-1 promoter activity. The activity decreased significantly (P < 0.05) in response to interleukin-1 (IL-1)beta (1 ng/ml) (45%), tumor necrosis factor (TNF)-alpha (50 ng/ml) (34%), epidermal growth factor (10 ng/ml) (54%), phorbol myristate acetate (10 nM) (70%), IL-4 (10 ng/ml) (50%), IL-8 (100 ng/ml) (72%) and Activin A (25 ng/ml) (32%). Whether this degree of change in promoter activity leads to physiologically relevant alterations in the amounts of PGHS-1 present in cells remains to be determined.
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Affiliation(s)
- R L Eykholt
- Department of Pharmacology and Clinical Pharmacology, The University of Auckland, Faculty of Medical and Health Sciences, Grafton, New Zealand.
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39
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Ohkawara S, Shimonishi M, Tanabe T, Yokoyama C. Cloning and characterization of 5'-flanking region of mouse prostacyclin synthase gene. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1494:155-61. [PMID: 11072079 DOI: 10.1016/s0167-4781(00)00212-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
To gain an insight into the mechanisms of prostacyclin expression, a genomic DNA clone harboring 2.0 kb of the 5'-flanking sequence of the mouse prostacyclin synthase (PGIS) gene was isolated. The 5'-flanking region did not possess a TATA box, but contained a GC-rich region and several consensus cis DNA elements. The major product of the primer extension analysis suggested that the transcription of the gene started from 72 bases upstream of the translational initiation codon. To analyze the PGIS promoter activity, the 2.0 kb fragment was fused to the luciferase gene and transient transfection assays were conducted with cultured rat vascular smooth muscle cells (VSMC). The fragment showed significant promoter activity in the cells. Analysis of a series of 5'-deletion constructs showed that the 5'-flanking regions spanning bases -371 to -285 and -229 to -119 were important for the basal transcriptional activity of the mouse PGIS gene. Gel mobility shift assays revealed that DNA-protein complexes were formed with the nuclear extracts from VSMC, and that the formation of these complexes was inhibited by excess consensus Sp1 oligonucleotide. Prior incubation of anti-Sp1 antibody with nuclear extracts in this assay resulted in supershift of the band for the DNA-protein complex. In addition, mutation of two Sp1 recognition motifs residing at bases -297 to -289 and -197 to -192 markedly reduced the basal PGIS promoter activity and retarded the band in a gel mobility shift assay. These results indicated that binding of one Sp1 to two Sp1 sites on the promoter region activated the basal transcription of the PGIS gene.
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MESH Headings
- Animals
- Base Sequence
- Cells, Cultured
- Cloning, Molecular
- Codon, Initiator/genetics
- Consensus Sequence/genetics
- Cytochrome P-450 Enzyme System/genetics
- DNA/genetics
- DNA/metabolism
- DNA-Binding Proteins/metabolism
- Gene Expression Regulation
- Genes, Reporter
- Intramolecular Oxidoreductases/genetics
- Mice
- Mice, Inbred C57BL
- Molecular Sequence Data
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/metabolism
- Promoter Regions, Genetic/genetics
- RNA, Messenger/analysis
- RNA, Messenger/genetics
- Rats
- Response Elements/genetics
- Sequence Deletion/genetics
- Sp1 Transcription Factor/physiology
- TATA Box/genetics
- Transfection
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Affiliation(s)
- S Ohkawara
- Department of Pharmacology, National Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, 565-8565, Osaka, Japan.
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40
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Xu Q, Ji YS, Schmedtje JF. Sp1 increases expression of cyclooxygenase-2 in hypoxic vascular endothelium. Implications for the mechanisms of aortic aneurysm and heart failure. J Biol Chem 2000; 275:24583-9. [PMID: 10825178 DOI: 10.1074/jbc.m003894200] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Cyclooxygenase-2 (COX-2) catalyzes prostaglandin synthesis from arachidonic acid and is expressed locally in aortic aneurysm and heart failure. Cellular hypoxia is also found in these conditions. We have previously shown that cox-2 is transcriptionally regulated by hypoxia in human umbilical vein endothelial cells (HUVEC) in culture via the transactivation factor NF-kappaB p65, leading to increased production of prostaglandin E(2), an inhibitor of vascular smooth muscle cell proliferation. Sp1 is a transactivation factor known to be important in the regulation of cytokine expression in association with NF-kappaB. We hypothesized that Sp1 is involved in the induction of cox-2 in hypoxic HUVEC. Electrophoretic mobility shift assays with hypoxic HUVEC nuclear protein showed that both Sp1 and the related protein Sp3 specifically bound to the cox-2 promoter. Immunoblotting demonstrated that hypoxia increased the nuclear localization of Sp1 but did not change the Sp3 content in HUVEC. Overexpression of Sp1 through transfection of HUVEC enhanced cox-2 promoter activity as measured by reporter gene expression and by the production of COX-2. The specificity of the results was confirmed by mutation of the Sp1-binding site in the cox-2 promoter construct and by reproducibility in an Sp-deficient Drosophila SL2 cell line. The regulatory role of Sp1 discovered in this work supports the concept that a mechanistic link exists between vascular cellular hypoxia and mediators of inflammation associated with aortic aneurysm and heart failure.
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Affiliation(s)
- Q Xu
- Section on Cardiology, Department of Medicine, and Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157-1045, USA
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41
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Eykholt RL, Hansen WR, Potter S, Marvin KW, Mitchell MD. Cytokines regulate prostaglandin H synthase-1 transcription in human amnion-derived cells. Prostaglandins Leukot Essent Fatty Acids 1999; 61:323-9. [PMID: 10670695 DOI: 10.1054/plef.1999.0108] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
We have isolated the prostaglandin H synthase-1 (PGHS-1) promoter from the human amnion cell line WISH by long template PCR. The fragment was 1124 base pairs in length and shared a 96% sequence identity with the sequence in GenBank. The putative transcription start site is located 18 bp upstream of the start codon. The sequence is TATA-less, but contains multiple Sp-1 sites and a GC box at -132. The fragment was subcloned into the promoterless reporter construct pBLCAT3 to produce the promoter reporter construct pPGHS1CAT. pPGHS1CAT expression in amnion-derived AV3 cells was inhibited by the pro-inflammatory cytokines tumor necrosis factor-alpha (TNF-alpha) and interleukin 1-beta (IL-1beta). PGHS-1 mRNA levels however, were unchanged over a 16-h time course with either treatment. These results suggest that PGHS-1 transcription is regulated in a negative manner by cytokines in human amnion-derived cells.
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Affiliation(s)
- R L Eykholt
- Department of Pharmacology and Clinical Pharmacology, University of Auckland, School of Medicine, Grafton, New Zealand.
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42
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Hansen WR, Keelan JA, Skinner SJ, Mitchell MD. Key enzymes of prostaglandin biosynthesis and metabolism. Coordinate regulation of expression by cytokines in gestational tissues: a review. Prostaglandins Other Lipid Mediat 1999; 57:243-57. [PMID: 10402218 DOI: 10.1016/s0090-6980(99)00008-8] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Preterm labor is frequently associated with ascending intrauterine infection, accompanied by leukocytes infiltration and enhanced local production of cytokines and other inflammatory mediators. The resulting amplification of the inflammatory response, and of prostanoid production in particular, is postulated to be a principal mechanism of infection-driven preterm labor. In this review the effects of pro- and anti-inflammatory cytokines are discussed with respect to the expression of enzymes involved in three key steps of prostanoid biosynthesis and metabolism: liberation of arachidonic acid (AA), conversion of AA to bioactive prostanoids, and prostanoid catabolism. We suggest that by exerting coordinate actions on all three key steps, through multiple molecular mechanisms, inflammatory cytokines acutely up-regulate prostanoid production in intrauterine tissues.
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Affiliation(s)
- W R Hansen
- Department of Pharmacology and Clinical Pharmacology, University of Auckland School of Medicine, New Zealand
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43
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Xu XM, Sansores-Garcia L, Chen XM, Matijevic-Aleksic N, Du M, Wu KK. Suppression of inducible cyclooxygenase 2 gene transcription by aspirin and sodium salicylate. Proc Natl Acad Sci U S A 1999; 96:5292-7. [PMID: 10220459 PMCID: PMC21857 DOI: 10.1073/pnas.96.9.5292] [Citation(s) in RCA: 217] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The pharmacological action of salicylate cannot be explained by its inhibition of cyclooxygenase (COX) activity. In this report, the effects of aspirin and sodium salicylate on COX-2 expressions in human umbilical vein endothelial cells and foreskin fibroblasts were evaluated. Aspirin and sodium salicylate at therapeutic concentrations equipotently blocked COX-2 mRNA and protein levels induced by interleukin-1beta and phorbol 12-myristate 13-acetate. The suppressing effect was more pronounced in cultured cells deprived of fetal bovine serum for 24 h, suggesting that it may be cell cycle related. Salicylate inhibited nascent COX-2 transcript synthesis but had no effect on COX-2 mRNA stability. It inhibited COX-2 promoter activity in a concentration-dependent manner. In mice pretreated with aspirin (10 and 30 mg/kg), followed by challenge with lipopolysaccharide, COX-2 mRNA expression in peritoneal macrophages was markedly suppressed. These findings suggest that salicylate exerts its antiinflammatory action in part by suppressing COX-2 induction, thereby reducing the synthesis of proinflammatory prostaglandins.
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Affiliation(s)
- X M Xu
- Vascular Biology Research Center and Division of Hematology, University of Texas-Houston Medical School, Houston, TX 77030, USA
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44
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Li J, Qu X, Schmidt AM. Sp1-binding elements in the promoter of RAGE are essential for amphoterin-mediated gene expression in cultured neuroblastoma cells. J Biol Chem 1998; 273:30870-8. [PMID: 9812979 DOI: 10.1074/jbc.273.47.30870] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Receptor for AGE (RAGE) and the polypeptide amphoterin are highly expressed and co-localized in neurons of the developing central nervous system of the rat. In vitro, the interaction of amphoterin with neuronal RAGE induces neurite outgrowth. We tested the hypothesis that interaction of amphoterin with neuronal cells enhances RAGE expression, thereby providing a mechanism by which amphoterin-mediated regulation of RAGE might contribute to promotion of neurite growth and spreading. Incubation of cultured neuroblastoma cells with amphoterin resulted in increased transcription and translation of RAGE, a process largely inhibited in the presence of anti-RAGE IgG but not by nonimmune IgG. To begin to delineate molecular mechanisms underlying these findings, we identified multiple putative binding elements within the 5'-flanking region of the RAGE gene for Sp1, a transcription factor that has been critically linked to the process of normal development. DNase I footprinting and electrophoretic mobility shift assays demonstrated multiple functional Sp1-binding sites within the region -245 to -40 of the RAGE promoter. Transient transfection of cultured SK-N-SH neuroblastoma cells with chimeric 5'-deletion constructs linked to luciferase reporter revealed that the region containing Sp1-binding elements did not contribute uniquely to basal expression of the RAGE gene. Simultaneous mutation of the multiple Sp1-binding elements in this region did not affect basal promoter function; however, promoter responsiveness to amphoterin was markedly attenuated. These results point to Sp1-dependent mechanisms underlying amphoterin-mediated increases in RAGE expression in neuroblastoma cells and further link amphoterin-RAGE interaction to development of the nervous system.
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Affiliation(s)
- J Li
- Division of Surgical Science, Department of Surgery, and Departments of Physiology and Medicine, Columbia University College of Physicians and Surgeons, New York, New York 10032, USA
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45
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Abstract
The recent identification, cloning, and characterization of two cyclooxygenases has provided insight into how nonsteroidal anti-inflammatory drugs can beneficially inhibit prostaglandin production in inflammation but also produce side-effects in the gut and kidney. The subtle differences in the sites in which these drugs bind the enzymes has allowed development of inhibitors that exhibit selectivity for the inflammatory cyclooxygenase and spare the housekeeping enzyme. This selectivity in theory should enhance the therapeutic potential of these new drugs.
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Affiliation(s)
- T J Smith
- Department of Medicine, Albany Medical College, New York, USA
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Jun SS, Chen Z, Pace MC, Shaul PW. Estrogen upregulates cyclooxygenase-1 gene expression in ovine fetal pulmonary artery endothelium. J Clin Invest 1998; 102:176-83. [PMID: 9649571 PMCID: PMC509079 DOI: 10.1172/jci2034] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Prostacyclin (PGI2) is a key mediator of pulmonary vasodilation in the perinatal period and its synthesis in the pulmonary vasculature increases markedly during late gestation due to enhanced expression of the rate-limiting enzyme cyclooxygenase-1 (COX-1). The hormone estrogen may play a role in COX-1 upregulation since fetal estrogen levels rise dramatically during late gestation and estrogen enhances PGI2 synthesis in nonpulmonary vascular cells. We therefore studied the direct effects of estrogen on COX-1 expression in ovine fetal pulmonary artery endothelial cells (PAEC). Exposure to estradiol-17beta (E2beta, 10(-)10 to 10(-)6 M) caused a dose-related increase in COX-1 mRNA expression that was evident after 48 h and maximal at 10(-)8 M (fourfold increase). COX-1 mRNA stability was unchanged, suggesting that the upregulation is mediated at the level of transcription. E2beta treatment (10(-)8 M for 48 h) also caused a threefold increase in COX-1 protein expression and a threefold increase in PGI2 synthesis stimulated by bradykinin, the calcium ionophore A23187, or arachidonic acid. The estrogen receptor (ER) antagonist ICI 182,780 fully reversed the effects of the hormone on COX-1 protein expression and on arachidonic acid-stimulated PGI2 synthesis, and ER expression was evident in the PAEC by immunoblot analysis. These findings indicate that physiologic levels of estrogen cause upregulation of COX-1 expression and PGI2 synthesis in fetal PAEC via activation of PAEC ER. This process may play a critical role in optimizing the capacity for PGI2-mediated pulmonary vasodilation at birth, and it may also be involved in estrogen responsiveness in other vascular beds.
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Affiliation(s)
- S S Jun
- Department of Pediatrics, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75235-9063, USA
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Liu W, Wilson JE. Two Sp sites are important cis elements regulating the upstream promoter region of the gene for rat type I hexokinase. Arch Biochem Biophys 1997; 346:142-50. [PMID: 9328294 DOI: 10.1006/abbi.1997.0295] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Multiple transcriptional start sites have been identified for the gene encoding the rat Type I isozyme of hexokinase (White, J.A., Liu, W., and Wilson, J. E., Arch. Biochem. Biophys. 335, 161-172, 1996); these are clustered at positions approximately -460, -300, and -100 relative to the translational start codon (ATG, with A being +1). PC12 cells and H9c2 cells were transfected with luciferase reporter constructs containing genomic sequence between positions -3366 and -171. Marked (85%) decrease in promoter activity was associated with deletion of sequence between -742 and -516. In DNase I footprinting experiments, two regions, called P1 (-552 to -529) and P2 (-480 to -458) boxes, were protected by proteins present in nuclear extracts from PC12 cells. Mutation or deletion of the P2 box had no effect on promoter activity; protection in this region, which includes the most upstream cluster of transcriptional start sites, is attributed to binding of RNA polymerase II or associated factors. In contrast, mutations or deletions in the P1 box had markedly detrimental effects on promoter activity and on binding of proteins in PC12 cell nuclear extracts. Maintenance of a consensus Sp1 binding site centrally located in the P1 box was critical for both promoter activity and binding. A second Sp1 site (-570), just upstream from the P1 box, was also shown to be functionally important but no protection of this region was detected in footprinting experiments, presumably reflecting lower affinity at this site under the conditions used. Supershift experiments demonstrated the involvement of Sp1, Sp3, and Sp4 in formation of complexes with the P1 box region and implicate these transcription factors in regulating promoter activity associated with this region. Another series of reporter constructs, including sequence between -171 and -1, permitted detection of an additional promoter activity downstream from -364. While not yet extensively characterized, it is already evident that the cis elements influencing the downstream promoter activity are distinct from the Sp factors determined to be important in expression from the upstream promoter region.
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Affiliation(s)
- W Liu
- Department of Biochemistry, Michigan State University, East Lansing 48824-1319, USA
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