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Vo TTT, Wee Y, Chen YL, Cheng HC, Tuan VP, Lee IT. Surfactin attenuates particulate matter-induced COX-2-dependent PGE 2 production in human gingival fibroblasts by inhibiting TLR2 and TLR4/MyD88/NADPH oxidase/ROS/PI3K/Akt/NF-κB signaling pathway. J Periodontal Res 2021; 56:1185-1199. [PMID: 34486757 DOI: 10.1111/jre.12932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Revised: 08/18/2021] [Accepted: 08/26/2021] [Indexed: 11/27/2022]
Abstract
OBJECTIVE To evaluate the anti-inflammatory effects of surfactin and underlying mechanisms against particulate matter (PM)-induced inflammatory responses in human gingival fibroblasts (HGFs). BACKGROUND PM, a major air pollutant, may associate with certain oral diseases possibly by inducing inflammation and oxidative stress. Surfactin, a potent biosurfactant, possesses various biological properties including anti-inflammatory activity. However, the underlying mechanisms are unclear. Also, there is no study investigating the effects of surfactin on PM-induced oral inflammatory responses. As an essential constituent of human periodontal connective tissues which involves immune-inflammatory responses, HGFs serve as useful study models. METHODS HGFs were pretreated with surfactin prior to PM incubation. The PGE2 production was determined by ELISA, while the protein expression and mRNA levels of COX-2 and upstream regulators were measured using Western blot and real-time PCR, respectively. The transcriptional activity of COX-2 and NF-κB were determined using promoter assay. ROS generation and NADPH oxidase activity were identified by specific assays. Co-immunoprecipitation assay, pharmacologic inhibitors, and siRNA transfection were applied to explore the interplay of molecules. Mice were given one dose of surfactin or different pharmacologic inhibitors, then PM was delivered into the gingiva for three consecutive days. Gingival tissues were obtained for analyzing COX-2 expression. RESULTS PM-treated HGFs released significantly higher COX-2-dependent PGE2 , which were regulated by TLR2 and TLR4/MyD88/NADPH oxidase/ROS/PI3K/Akt/NF-κB pathway. PM-induced COX-2/PGE2 increase was effectively reversed by surfactin through the disruption of regulatory pathway. Similar inhibitory effects of surfactin was observed in mice. CONCLUSION Surfactin may elicit anti-inflammatory effects against PM-induced oral inflammatory responses.
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Affiliation(s)
- Thi Thuy Tien Vo
- School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei, Taiwan
| | - Yinshen Wee
- Department of Pathology, University of Utah, Salt Lake City, Utah, USA
| | - Yuh-Lien Chen
- Department of Anatomy and Cell Biology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Hsin-Chung Cheng
- School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei, Taiwan.,Department of Dentistry, Taipei Medical University Hospital, Taipei, Taiwan
| | - Vo Phuoc Tuan
- Endoscopy Department, Cho Ray Hospital, Ho Chi Minh City, Vietnam
| | - I-Ta Lee
- School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei, Taiwan
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2
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The Entry and Egress of Monocytes in Atherosclerosis: A Biochemical and Biomechanical Driven Process. Cardiovasc Ther 2021; 2021:6642927. [PMID: 34345249 PMCID: PMC8282391 DOI: 10.1155/2021/6642927] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 06/28/2021] [Indexed: 12/24/2022] Open
Abstract
In accordance with “the response to injury” theory, the entry of monocytes into the intima guided by inflammation signals, taking up cholesterol and transforming into foam cells, and egress from plaques determines the progression of atherosclerosis. Multiple cytokines and receptors have been reported to be involved in monocyte recruitment such as CCL2/CCR2, CCL5/CCR5, and CX3CL1/CX3CR1, and the egress of macrophages from the plaque like CCR7/CCL19/CCL21. Interestingly, some neural guidance molecules such as Netrin-1 and Semaphorin 3E have been demonstrated to show an inhibitory effect on monocyte migration. During the processes of monocytes recruitment and migration, factors affecting the biomechanical properties (e.g., the membrane fluidity, the deformability, and stiffness) of the monocytes, like cholesterol, amyloid-β peptide (Aβ), and lipopolysaccharides (LPS), as well as the biomechanical environment that the monocytes are exposed, like the extracellular matrix stiffness, mechanical stretch, blood flow, and hypertension, were discussed in the latter section. Till now, several small interfering RNAs (siRNAs), monoclonal antibodies, and antagonists for CCR2 have been designed and shown promising efficiency on atherosclerosis therapy. Seeking more possible biochemical factors that are chemotactic or can affect the biomechanical properties of monocytes, and uncovering the underlying mechanism, will be helpful in future studies.
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An L, Shen Y, Chopp M, Zacharek A, Venkat P, Chen Z, Li W, Qian Y, Landschoot-Ward J, Chen J. Deficiency of Endothelial Nitric Oxide Synthase (eNOS) Exacerbates Brain Damage and Cognitive Deficit in A Mouse Model of Vascular Dementia. Aging Dis 2021; 12:732-746. [PMID: 34094639 PMCID: PMC8139201 DOI: 10.14336/ad.2020.0523] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 05/23/2020] [Indexed: 12/19/2022] Open
Abstract
Vascular Dementia (VaD) accounts for nearly 20% of all cases of dementia. eNOS plays an important role in neurovascular remodeling, anti-inflammation, and cognitive functional recovery after stroke. In this study, we investigated whether eNOS regulates brain damage, cognitive function in mouse model of bilateral common carotid artery stenosis (BCAS) induced VaD. Late-adult (6-8 months) C57BL/6J and eNOS knockout (eNOS-/-) mice were subjected to BCAS (n=12/group) or sham group (n=8/group). BCAS was performed by applying microcoils to both common carotid arteries. Cerebral blood flow (CBF) and blood pressure were measured. A battery of cognitive functional tests was performed, and mice were sacrificed 30 days after BCAS. Compared to corresponding sham mice, BCAS in wild-type (WT) and eNOS-/- mice significantly: 1) induces short term, long term memory loss, spatial learning and memory deficits; 2) decreases CBF, increases ischemic cell damage, including apoptosis, white matter (WM) and axonal damage; 3) increases blood brain barrier (BBB) leakage, decreases aquaporin-4 (AQP4) expression and vessel density; 4) increases microglial, astrocyte activation and oxidative stress in the brain; 5) increases inflammatory factor interleukin-1 receptor-associated kinase-1(IRAK-1) and amyloid beta (Aβ) expression in brain; 6) increases IL-6 and IRAK4 expression in brain. eNOS-/-sham mice exhibit increased blood pressure, decreased iNOS and nNOS in brain compared to WT-sham mice. Compared to WT-BCAS mice, eNOS-/-BCAS mice exhibit worse vascular and WM/axonal damage, increased BBB leakage and inflammatory response, increased cognitive deficit, decreased iNOS, nNOS in brain. eNOS deficit exacerbates BCAS induced brain damage and cognitive deficit.
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Affiliation(s)
- Lulu An
- 1Department of Neurology, Henry Ford Hospital, Detroit, MI-48202, USA
| | - Yi Shen
- 1Department of Neurology, Henry Ford Hospital, Detroit, MI-48202, USA.,2Department of Neurology, Tianjin Medical University General Hospital, Tianjin, China (Current address)
| | - Michael Chopp
- 1Department of Neurology, Henry Ford Hospital, Detroit, MI-48202, USA.,3Department of Physics, Oakland University, Rochester, MI-48309, USA
| | - Alex Zacharek
- 1Department of Neurology, Henry Ford Hospital, Detroit, MI-48202, USA
| | - Poornima Venkat
- 1Department of Neurology, Henry Ford Hospital, Detroit, MI-48202, USA
| | - Zhili Chen
- 1Department of Neurology, Henry Ford Hospital, Detroit, MI-48202, USA
| | - Wei Li
- 1Department of Neurology, Henry Ford Hospital, Detroit, MI-48202, USA
| | - Yu Qian
- 1Department of Neurology, Henry Ford Hospital, Detroit, MI-48202, USA
| | | | - Jieli Chen
- 1Department of Neurology, Henry Ford Hospital, Detroit, MI-48202, USA
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DeJulius CR, Gulati S, Hasty KA, Crofford LJ, Duvall CL. Recent Advances in Clinical Translation of Intra-Articular Osteoarthritis Drug Delivery Systems. ADVANCED THERAPEUTICS 2021; 4:2000088. [PMID: 33709019 PMCID: PMC7941755 DOI: 10.1002/adtp.202000088] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Indexed: 12/12/2022]
Abstract
Osteoarthritis (OA) is a degenerative disease of the joints and a leading cause of physical disability in adults. Intra-articular (IA) therapy is a popular treatment strategy for localized, single-joint OA; however, small-molecule drugs such as corticosteroids do not provide prolonged relief. One possible reason for their lack of efficacy is high clearance rates from the joint through constant lymphatic drainage of the synovial tissues and synovial fluid and also by their exchange via the synovial vasculature. Advanced drug delivery strategies for extended release of therapeutic agents in the joint space is a promising approach to improve outcomes for OA patients. Broadly, the basic principle behind this strategy is to encapsulate therapeutic agents in a polymeric drug delivery system (DDS) for diffusion- and/or degradation-controlled release, whereby degradation can occur by hydrolysis or tied to relevant microenvironmental cues such as pH, reactive oxygen species (ROS), and protease activity. In this review, we highlight the development of clinically tested IA therapies for OA and highlight recent systems which have been investigated preclinically. DDS strategies including hydrogels, liposomes, polymeric microparticles (MPs) and nanoparticles (NPs), drug conjugates, and combination systems are introduced and evaluated for clinical translational potential.
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Affiliation(s)
- Carlisle R DeJulius
- Department of Biomedical Engineering, Vanderbilt University, 5824 Stevenson Center, Nashville, TN 37232, United States
| | - Shubham Gulati
- Department of Biomedical Engineering, Vanderbilt University, 5824 Stevenson Center, Nashville, TN 37232, United States
| | - Karen A Hasty
- Department of Orthopedic Surgery and Biomedical Engineering, University of Tennessee Health Science Center, 1211 Union Ave. Suite 520, Memphis, TN 38104, United States
| | - Leslie J Crofford
- Department of Medicine, Division of Rheumatology and Immunology, Vanderbilt University Medical Center, 1161 21 Ave. S., Nashville, TN 37232, United States
| | - Craig L Duvall
- Department of Biomedical Engineering, Vanderbilt University, 5824 Stevenson Center, Nashville, TN 37232, United States
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Regulatory expression of bone morphogenetic protein 6 by 2,2'-dipyridyl. Biochim Biophys Acta Gen Subj 2020; 1864:129610. [PMID: 32251709 DOI: 10.1016/j.bbagen.2020.129610] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2019] [Revised: 03/18/2020] [Accepted: 03/30/2020] [Indexed: 01/01/2023]
Abstract
BACKGROUND Expression of hepcidin, a hormone produced by hepatocytes which negatively regulates the circulating iron levels, is known to be positively regulated by BMP6, a member of transforming growth factor (TGF)-β family. Previous studies have shown that iron status is sensed by sinusoidal endothelial cells of hepatic lamina, leading to the modulation of BMP6 expression. METHODS ISOS-1, HUVEC, F-2, and SK-HEP1 endothelial cells were treated with either iron or 2,2'-dipyridyl (2DP), a cell-permeable iron-chelator, and expression level of Bmp6 was examined. To identify factors affecting Bmp6 transcription, stimulus screening for regulator of transcription (SSRT) was developed. RESULTS Treatment with iron slightly increased the expression levels of Bmp6, while 2DP unexpectedly increased Bmp6 expression in a dose-dependent manner. 2DP-induced Bmp6 expression was resistant to co-treatment with iron. 2DP-induced Bmp6 expression was also detected in HUVEC, F-2 cells, and SK-HEP1 cells. Luciferase-based reporter assays indicated that forced expression of JunB increased the transcription of Bmp6. 2DP induced phosphorylation of JunB; co-treatment with SP600125 blocked the 2DP-induced Bmp6 expression partially. JunB-induced Bmp6 transcription was not affected by mutations of putative JunB-responsive elements. Some endoplasmic reticulum stress inducers increased the expression of Bmp6. SSRT revealed pathways regulating Bmp6 transcription positively and negatively. Hepa1-6 liver cells and C2C12 myogenic cells were prone to 2DP induced Bmp6 expression. CONCLUSIONS The present study reveals non‑iron-regulated Bmp6 expression in endothelial cells. GENERAL SIGNIFICANCE Regulatory expression of Bmp6 may be important as a key step for fine tuning of BMP activity.
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Tsai MH, Wu CH, Lin WN, Cheng CY, Chuang CC, Chang KT, Jiang RS, Hsu JF, Lee IT. Infection with Staphylococcus aureus elicits COX-2/PGE2/IL-6/MMP-9-dependent aorta inflammation via the inhibition of intracellular ROS production. Biomed Pharmacother 2018; 107:889-900. [DOI: 10.1016/j.biopha.2018.08.096] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 08/03/2018] [Accepted: 08/17/2018] [Indexed: 12/21/2022] Open
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Mendonca P, Taka E, Bauer D, Reams RR, Soliman KFA. The attenuating effects of 1,2,3,4,6 penta-O-galloyl-β-d-glucose on pro-inflammatory responses of LPS/IFNγ-activated BV-2 microglial cells through NFƙB and MAPK signaling pathways. J Neuroimmunol 2018; 324:43-53. [PMID: 30236786 DOI: 10.1016/j.jneuroim.2018.09.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2018] [Revised: 08/28/2018] [Accepted: 09/10/2018] [Indexed: 12/14/2022]
Abstract
BACKGROUND Overactivated microglial cells exhibit chronic inflammatory response and can lead to the continuous production of pro-inflammatory cytokines, perpetuating inflammation, and ultimately resulting in neuronal injury. 1,2,3,4,6-Penta-O-Galloyl-β-d-Glucose (PGG), which is a naturally occurring polyphenolic compound, has exhibited anti-inflammatory effect through the inhibition of many cytokines in different experimental models, but its effect on activated microglia cells was never described. In the present study, we investigated PGG effect in proteins involved in the NFƙB and MAPK signaling pathways, which play a central role in inflammation through their ability to induce transcription of pro-inflammatory genes. METHODS PCR arrays and RT-PCR with individual primers were used to determine the effect of PGG on mRNA expression of genes involved in NFƙB and MAPK signaling pathways. Western blots were performed to confirm PCR results. RESULTS The data obtained showed that PGG modulated the expression of 5 genes from the NFƙB (BIRC3, CHUK, IRAK1, NFƙB1, NOD1) and 2 genes from MAPK signaling pathway (CDK2 and MYC) when tested in RT-PCR assays. Western blots confirmed the PCR results at the protein level, showing that PGG attenuated the expression of total and phosphorylated proteins (CDK2, CHUK, IRAK1, and NFƙB1) involved in NFƙB and MAPK signaling. CONCLUSION These findings show that PGG could modulate the expression of genes and proteins involved in the production of pro-inflammatory cytokines in microglia cells.
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Affiliation(s)
- Patricia Mendonca
- College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL 32307, United States
| | - Equar Taka
- College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL 32307, United States
| | - David Bauer
- College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL 32307, United States
| | - Renee R Reams
- College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL 32307, United States
| | - Karam F A Soliman
- College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL 32307, United States.
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8
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Kong D, Wang Z, Tian J, Liu T, Zhou H. Glycyrrhizin inactivates toll-like receptor (TLR) signaling pathway to reduce lipopolysaccharide-induced acute lung injury by inhibiting TLR2. J Cell Physiol 2018; 234:4597-4607. [PMID: 30203548 DOI: 10.1002/jcp.27242] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 07/24/2018] [Indexed: 01/08/2023]
Abstract
OBJECTIVE This study aimed to explore glycyrrhizin on acute lung injury (ALI) and how glycyrrhizin (GL) attenuated lipopolysaccharide (LPS)-induced ALI. METHODS Bioinformatics analysis was performed to screen the expressed genes in LPS-induced ALI mice. The enrichment of functions and signaling pathways of deregulated genes were conducted. Combined with DIGSEE and STICH, the target gene for further investigation was chosen. To verify target gene in mice, we performed experiment in vivo. Forty mice were randomized into NC, LPS, LPS + S, and LPS + GL group. Mice in the LPS + GL group received glycyrrhizin l mg and mice in LPS + S received saline. Then, HE and Masson staining detected pathological changes of lung tissues; enzyme-linked immunosorbent assay analyzed bronchoalveolar lavage fluid concentrations of MIP-2, mice growth-related oncogene homologue (KC), IL-4, IL-6, GM-CSF, IFN-γ, and IgM; western blot analysis determined the expression of toll-like receptor (TLR) signaling and NF-κB pathway-related proteins. RESULTS Tlr2 which was not only upregulated but also closely related to glycyrrhizin. TLR2 was upregulated in following LPS induced in cells and TLR2 overexpression-activated TLR signaling pathway to promote ALI. After glycyrrhizin treatment, the expression of TLR2 was reduced. Furthermore, it was found out that the number of inflammatory cells, collagen deposition, MIP-2, KC, IL-4, IL-6, GM-CSF, and IFN-γ expression increased in ALI mice and glycyrrhizin mitigated it. Similarly, the expression of TLR signaling pathway and NF-κB pathway-related protein also increased. CONCLUSION Glycyrrhizin functioned as a suppressor in TLR signaling pathway to reduce LPS-induced ALI by inhibiting TLR2.
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Affiliation(s)
- Delei Kong
- Department of Respiratory Medicine, First Affiliated Hospital of China Medical University, Shenyang, China
| | - Zanfeng Wang
- Department of Respiratory Medicine, First Affiliated Hospital of China Medical University, Shenyang, China
| | - Jie Tian
- Department of Respiratory Medicine, First Affiliated Hospital of China Medical University, Shenyang, China
| | - Tingwei Liu
- Department of Respiratory Medicine, First Affiliated Hospital of China Medical University, Shenyang, China
| | - Hui Zhou
- Department of Respiratory Medicine, First Affiliated Hospital of China Medical University, Shenyang, China
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Yum HW, Park J, Park HJ, Shin JW, Cho YY, Kim SJ, Kang JX, Surh YJ. Endogenous ω-3 Fatty Acid Production by fat-1 Transgene and Topically Applied Docosahexaenoic Acid Protect against UVB-induced Mouse Skin Carcinogenesis. Sci Rep 2017; 7:11658. [PMID: 28912452 PMCID: PMC5599646 DOI: 10.1038/s41598-017-11443-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 08/24/2017] [Indexed: 01/18/2023] Open
Abstract
The present study was intended to explore the effects of endogenously produced ω-3 polyunsaturated fatty acids (PUFAs) on ultraviolet B (UVB)-induced skin inflammation and photocarcinogenesis using hairless fat-1 transgenic mice harboring ω-3 desaturase gene capable of converting ω-6 to ω-3 PUFAs. Upon exposure to UVB irradiation, fat-1 transgenic mice exhibited a significantly reduced epidermal hyperplasia, oxidative skin damage, and photocarcinogenesis as compared to wild type mice. The transcription factor, Nrf2 is a master regulator of anti-inflammatory and antioxidant gene expression. While the protein expression of Nrf2 was markedly enhanced, the level of its mRNA transcript was barely changed in the fat-1 transgenic mouse skin. Topical application of docosahexaenoic acid (DHA), a representative ω-3 PUFA, in wild type hairless mice induced expression of the Nrf2 target protein, heme oxygenase-1 in the skin and protected against UVB-induced oxidative stress, inflammation and papillomagenesis. Furthermore, transient overexpression of fat-1 gene in mouse epidermal JB6 cells resulted in the enhanced accumulation of Nrf2 protein. Likewise, DHA treated to JB6 cells inhibited Nrf2 ubiquitination and stabilized it. Taken together, our results indicate that functional fat-1 and topically applied DHA potentiate cellular defense against UVB-induced skin inflammation and photocarcinogenesis through elevated activation of Nrf2 and upregulation of cytoprotective gene expression.
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Affiliation(s)
- Hye-Won Yum
- Tumor Microenvironment Global Core Research Center, College of Pharmacy, Seoul National University, Seoul, 08826, South Korea.,Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul, 08826, South Korea
| | - Jin Park
- Tumor Microenvironment Global Core Research Center, College of Pharmacy, Seoul National University, Seoul, 08826, South Korea.,Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Sciences and Technology, Seoul National University, Seoul, 08826, South Korea
| | - Hyun-Jung Park
- Cancer Research Institute, Seoul National University, Seoul, 03080, South Korea
| | - Jun Wan Shin
- Tumor Microenvironment Global Core Research Center, College of Pharmacy, Seoul National University, Seoul, 08826, South Korea.,Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul, 08826, South Korea
| | - Yong-Yeon Cho
- Integrated Research Institute of Pharmaceutical Sciences, College of Pharmacy, The Catholic University of Korea, Bucheon, Gyeonggi-do, 420-743, South Korea
| | - Su-Jung Kim
- Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Sciences and Technology, Seoul National University, Seoul, 08826, South Korea
| | - Jing X Kang
- Laboratory for Lipid Medicine and Technology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 02129, USA
| | - Young-Joon Surh
- Tumor Microenvironment Global Core Research Center, College of Pharmacy, Seoul National University, Seoul, 08826, South Korea. .,Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul, 08826, South Korea. .,Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Sciences and Technology, Seoul National University, Seoul, 08826, South Korea. .,Cancer Research Institute, Seoul National University, Seoul, 03080, South Korea.
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Machado I, Gonzalez PV, Vilcaes A, Carniglia L, Schiöth HB, Lasaga M, Scimonelli TN. Interleukin-1β-induced memory reconsolidation impairment is mediated by a reduction in glutamate release and zif268 expression and α-melanocyte-stimulating hormone prevented these effects. Brain Behav Immun 2015; 46:137-46. [PMID: 25637483 DOI: 10.1016/j.bbi.2015.01.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Revised: 12/26/2014] [Accepted: 01/17/2015] [Indexed: 01/31/2023] Open
Abstract
The immune system is an important modulator of learning, memory and neural plasticity. Interleukin 1β (IL-1β), a pro-inflammatory cytokine, significantly affects several cognitive processes. Previous studies by our group have demonstrated that intrahippocampal administration of IL-1β impairs reconsolidation of contextual fear memory. This effect was reversed by the melanocortin alpha-melanocyte-stimulating hormone (α-MSH). The mechanisms underlying the effect of IL-1β on memory reconsolidation have not yet been established. Therefore, we examined the effect of IL-1β on glutamate release, ERK phosphorylation and the activation of the transcription factor zinc finger- 268 (zif268) during reconsolidation. Our results demonstrated that IL-1β induced a significant decrease of glutamate release after reactivation of the fear memory and this effect was related to calcium concentration in hippocampal synaptosomes. IL-1β also reduced ERK phosphorylation and zif268 expression in the hippocampus. Central administration of α-MSH prevented the decrease in glutamate release, ERK phosphorylation and zif268 expression induced by IL-1β. Our results establish possible mechanisms involved in the detrimental effect of IL-1β on memory reconsolidation and also indicate that α-MSH may exert a beneficial modulatory role in preventing IL-1β effects.
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Affiliation(s)
- Ivana Machado
- IFEC-CONICET, Depto. Farmacología, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina
| | - Patricia V Gonzalez
- IFEC-CONICET, Depto. Farmacología, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina
| | - Alejandro Vilcaes
- CIQUIBIC-CONICET, Departamento de Química Biológica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina
| | - Lila Carniglia
- Instituto de Investigaciones Biomédicas INBIOMED UBA-CONICET, Facultad de Medicina, Buenos Aires, Argentina
| | - Helgi B Schiöth
- Department of Neuroscience, Functional Pharmacology, Uppsala University, Uppsala, Sweden
| | - Mercedes Lasaga
- Instituto de Investigaciones Biomédicas INBIOMED UBA-CONICET, Facultad de Medicina, Buenos Aires, Argentina
| | - Teresa N Scimonelli
- IFEC-CONICET, Depto. Farmacología, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina.
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11
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Cyclooxygenase-dependent signaling is causally linked to non-melanoma skin carcinogenesis: pharmacological, genetic, and clinical evidence. Cancer Metastasis Rev 2011; 30:343-61. [DOI: 10.1007/s10555-011-9306-z] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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12
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Lu YCS, Evans CH, Grodzinsky AJ. Effects of short-term glucocorticoid treatment on changes in cartilage matrix degradation and chondrocyte gene expression induced by mechanical injury and inflammatory cytokines. Arthritis Res Ther 2011; 13:R142. [PMID: 21888631 PMCID: PMC3308070 DOI: 10.1186/ar3456] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2011] [Revised: 05/06/2011] [Accepted: 09/02/2011] [Indexed: 01/13/2023] Open
Abstract
Introduction Traumatic joint injury damages cartilage and causes adjacent joint tissues to release inflammatory cytokines, increasing the risk of developing osteoarthritis. The main objective of this study was to determine whether the combined catabolic effects of mechanical injury, tumor necrosis factor alpha (TNFα) and interleukin-6 (IL-6)/soluble IL-6 receptor (sIL-6R) on cartilage could be abolished by short-term treatment with glucocorticoids such as dexamethasone. Methods In an initial dexamethasone-dose-response study, bovine cartilage explants were treated with TNFα and increasing concentrations of dexamethasone. Bovine and human cartilage explants were then subjected to individual and combined treatments with TNFα, IL-6/sIL-6R and injury in the presence or absence of dexamethasone. Treatment effects were assessed by measuring glycosaminoglycans (GAG) release to the medium and synthesis of proteoglycans. Additional experiments tested whether pre-exposure of cartilage to dexamethasone could prevent GAG loss and inhibition of biosynthesis induced by cytokines, and whether post-treatment with dexamethasone could diminish the effects of pre-established cytokine insult. Messenger ribonucleic acid (mRNA) levels for genes involved in cartilage homeostasis (proteases, matrix molecules, cytokines, growth and transcription factors) were measured in explants subjected to combined treatments with injury, TNFα and dexamethasone. To investigate mechanisms associated with dexamethasone regulation of chondrocyte metabolic response, glucocorticoid receptor (GR) antagonist (RU486) and proprotein convertase inhibitor (RVKR-CMK) were used. Results Dexamethasone dose-dependently inhibited GAG loss and the reduction in biosynthesis caused by TNFα. The combination of mechanical injury, TNFα and IL-6/sIL-6R caused the most severe GAG loss; dexamethasone reduced this GAG loss to control levels in bovine and human cartilage. Additionally, dexamethasone pre-treatment or post-treatment of bovine explants lowered GAG loss and increased proteoglycan synthesis in cartilage explants exposed to TNFα. Dexamethasone did not down-regulate aggrecanase mRNA levels. Post-transcriptional regulation by dexamethasone of other genes associated with responses to injury and cytokines was noted. GR antagonist reversed the effect of dexamethasone on sulfate incorporation. RVKR-CMK significantly reduced GAG loss caused by TNFα + IL-6 + injury. Conclusions Short-term glucocorticoid treatment effectively abolished the catabolic effects exerted by the combination of pro-inflammatory cytokines and mechanical injury: dexamethasone prevented proteoglycan degradation and restored biosynthesis. Dexamethasone appears to regulate the catabolic response of chondrocytes post-transcriptionally, since the abundance of transcripts encoding aggrecanases was still elevated in the presence of dexamethasone.
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Affiliation(s)
- Yihong C S Lu
- Department of Biological Engineering, MIT, 500 Technology Square NE47-377, Cambridge, MA 02139, USA
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13
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Machado I, González P, Schiöth HB, Lasaga M, Scimonelli TN. α-Melanocyte-stimulating hormone (α-MSH) reverses impairment of memory reconsolidation induced by interleukin-1 beta (IL-1 beta) hippocampal infusions. Peptides 2010; 31:2141-4. [PMID: 20688120 DOI: 10.1016/j.peptides.2010.07.018] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2010] [Revised: 07/15/2010] [Accepted: 07/15/2010] [Indexed: 12/14/2022]
Abstract
Interleukin-1 beta (IL-1β) significantly influences cognitive processes. Treatments which raise the level of IL-1β in the brain impair memory consolidation in contextual fear conditioning. However, the effect of IL-1β on memory reconsolidation has not yet been established. The melanocortin α-melanocyte-stimulating hormone (α-MSH) exerts potent anti-inflammatory actions by antagonizing the effect of proinflammatory cytokines. Five subtypes of melanocortin receptors (MC1R-MC5R) have been identified, of which MC3R and MC4R are predominant in the central nervous system. The present experiments show that the injection of IL-1β (5 ng/0.25 μl) in dorsal hippocampus up to 30 min after re-exposition to the context decreases freezing during the contextual fear test. Impairment of memory reconsolidation was reversed by treatment with α-MSH (0.05 μg/0.25 μl). Administration of the MC4 receptor antagonist HS014 (0.5 μg/0.25 μl) blocked the effect of α-MSH. These results suggest that IL-1β may influence memory reconsolidation and that activation of central MC4R could lead to improve cognitive performance.
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Affiliation(s)
- Ivana Machado
- IFEC CONICET Departamento Farmacología, Facultad de Ciencias Químicas, UNC, Córdoba, Argentina
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14
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Cui JG, Li YY, Zhao Y, Bhattacharjee S, Lukiw WJ. Differential regulation of interleukin-1 receptor-associated kinase-1 (IRAK-1) and IRAK-2 by microRNA-146a and NF-kappaB in stressed human astroglial cells and in Alzheimer disease. J Biol Chem 2010; 285:38951-60. [PMID: 20937840 DOI: 10.1074/jbc.m110.178848] [Citation(s) in RCA: 226] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Specific microRNAs (miRNAs), small non-coding RNAs that support homeostatic gene expression, are significantly altered in abundance in human neurological disorders. In monocytes, increased expression of an NF-κB-regulated miRNA-146a down-regulates expression of the interleukin-1 receptor-associated kinase-1 (IRAK-1), an essential component of Toll-like/IL-1 receptor signaling. Here we extend those observations to the hippocampus and neocortex of Alzheimer disease (AD) brain and to stressed human astroglial (HAG) cells in primary culture. In 66 control and AD samples we note a significant up-regulation of miRNA-146a coupled to down-regulation of IRAK-1 and a compensatory up-regulation of IRAK-2. Using miRNA-146a-, IRAK-1-, or IRAK-2 promoter-luciferase reporter constructs, we observe decreases in IRAK-1 and increases in miRNA-146a and IRAK-2 expression in interleukin-1β (IL-1β) and amyloid-β-42 (Aβ42) peptide-stressed HAG cells. NF-κB-mediated transcriptional control of human IRAK-2 was localized to between -119 and +12 bp of the immediate IRAK-2 promoter. The NF-κB inhibitors curcumin, pyrrolidine dithiocarbamate or CAY10512 abrogated both IRAK-2 and miRNA-146a expression, whereas IRAK-1 was up-regulated. Incubation of a protected antisense miRNA-146a was found to inhibit miRNA-146a and restore IRAK-1, whereas IRAK-2 remained unaffected. These data suggest a significantly independent regulation of IRAK-1 and IRAK-2 in AD and in IL-1β+Aβ42 peptide-stressed HAG cells and that an inducible, NF-κB-sensitive, miRNA-146a-mediated down-regulation of IRAK-1 coupled to an NF-κB-induced up-regulation of IRAK-2 expression drives an extensively sustained inflammatory response. The interactive signaling of NF-κB and miRNA-146a further illustrate interplay between inducible transcription factors and pro-inflammatory miRNAs that regulate brain IRAK expression. The combinatorial use of NF-κB inhibitors with miRNA-146a or antisense miRNA-146a may have potential as a bi-pronged therapeutic strategy directed against IRAK-2-driven pathogenic signaling.
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Affiliation(s)
- Jian Guo Cui
- Department of Ophthalmology, Louisiana State University Health Science Center, New Orleans, Louisiana 70112, USA
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15
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Sun H, Xu B, Inoue H, Chen QM. p38 MAPK mediates COX-2 gene expression by corticosterone in cardiomyocytes. Cell Signal 2008; 20:1952-9. [DOI: 10.1016/j.cellsig.2008.07.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2008] [Revised: 06/19/2008] [Accepted: 07/03/2008] [Indexed: 01/09/2023]
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16
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Fu S, Zhao H, Shi J, Abzhanov A, Crawford K, Ohno-Machado L, Zhou J, Du Y, Kuo WP, Zhang J, Jiang M, Jin JG. Peripheral arterial occlusive disease: global gene expression analyses suggest a major role for immune and inflammatory responses. BMC Genomics 2008; 9:369. [PMID: 18673543 PMCID: PMC2529314 DOI: 10.1186/1471-2164-9-369] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2007] [Accepted: 08/01/2008] [Indexed: 11/17/2022] Open
Abstract
Background Peripheral arterial disease (PAD), a major manifestation of atherosclerosis, is associated with significant cardiovascular morbidity, limb loss and death. However, mechanisms underlying the genesis and progression of the disease are far from clear. Genome-wide gene expression profiling of clinical samples may represent an effective approach to gain relevant information. Results After histological classification, a total of 30 femoral artery samples, including 11 intermediate lesions, 14 advanced lesions and 5 normal femoral arteries, were profiled using Affymetrix microarray platform. Following real-time RT-PCR validation, different algorithms of gene selection and clustering were applied to identify differentially expressed genes. Under a stringent cutoff, i.e., a false discovery rate (FDR) <0.5%, we found 366 genes were differentially regulated in intermediate lesions and 447 in advanced lesions. Of these, 116 genes were overlapped between intermediate and advanced lesions, including 68 up-regulated genes and 48 down-regulated ones. In these differentially regulated genes, immune/inflammatory genes were significantly up-regulated in different stages of PAD, (85/230 in intermediate lesions, 37/172 in advanced lesions). Through literature mining and pathway analysis using different databases such as Gene Ontology (GO), and the Kyoto Encyclopedia of Gene and Genomics (KEGG), genes involved in immune/inflammatory responses were significantly enriched in up-regulated genes at different stages of PAD(p < 0.05), revealing a significant correlation between immune/inflammatory responses and disease progression. Moreover, immune-related pathways such as Toll-like receptor signaling and natural killer cell mediated cytotoxicity were particularly enriched in intermediate and advanced lesions (P < 0.05), highlighting their pathogenic significance during disease progression. Conclusion Lines of evidence revealed in this study not only support previous hypotheses, primarily based on studies of animal models and other types of arterial disease, that inflammatory responses may influence the development of PAD, but also permit the recognition of a wide spectrum of immune/inflammatory genes that can serve as signatures for disease progression in PAD. Further studies of these signature molecules may eventually allow us to develop more sophisticated protocols for pharmaceutical interventions.
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Affiliation(s)
- Shijun Fu
- Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences and Shanghai Jiao Tong University School of Medicine, Shanghai, PR China.
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17
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Methylprednisolone protects oligodendrocytes but not neurons after spinal cord injury. J Neurosci 2008; 28:3141-9. [PMID: 18354017 DOI: 10.1523/jneurosci.5547-07.2008] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Methylprednisolone (MP) is used to treat a variety of neurological disorders involving white matter injury, including multiple sclerosis, acute disseminated encephalomyelitis, and spinal cord injury (SCI). Although its mechanism of action has been attributed to anti-inflammatory or antioxidant properties, we examined the possibility that MP may have direct neuroprotective activities. Neurons and oligodendrocytes treated with AMPA or staurosporine died within 24 h after treatment. MP attenuated oligodendrocyte death in a dose-dependent manner; however, neurons were not rescued by the same doses of MP. This protective effect was reversed by the glucocorticoid receptor (GR) antagonist (11, 17)-11-[4-(dimethylamino)phenyl]-17-hydroxy-17-(1-propynyl)estra-4,9-dien-3-one (RU486) and small interfering RNA directed against GR, suggesting a receptor-dependent mechanism. MP reversed AMPA-induced decreases in the expression of anti-apoptotic Bcl-x(L), caspase-3 activation, and DNA laddering, suggesting anti-apoptotic activity in oligodendrocytes. To examine whether MP demonstrated this selective protection in vivo, neuronal and oligodendrocyte survival was assessed in rats subjected to spinal cord injury (SCI); groups of rats were treated with or without MP in the presence or absence of RU486. Eight days after SCI, MP significantly increased oligodendrocytes (CC-1-immunoreactive cells) after SCI, but neuronal (neuronal-specific nuclear protein-immunoreactive cells) number remained unchanged; RU486 reversed this protective effect. MP also inhibited SCI-induced decreases in Bcl-x(L) and caspase-3 activation. Consistent with these findings, the volume of demyelination, assessed by Luxol fast blue staining, was attenuated by MP and reversed by RU486. These results suggest that MP selectively inhibits oligodendrocyte but not neuronal cell death via a receptor-mediated action and may be a mechanism for its limited protective effect after SCI.
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18
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Evaluation of beneficial and adverse effects of glucocorticoids on a newly developed full-thickness skin model. Toxicol In Vitro 2008; 22:747-59. [DOI: 10.1016/j.tiv.2007.11.022] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2007] [Revised: 11/13/2007] [Accepted: 11/28/2007] [Indexed: 11/21/2022]
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19
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Sales KJ, Grant V, Jabbour HN. Prostaglandin E2 and F2alpha activate the FP receptor and up-regulate cyclooxygenase-2 expression via the cyclic AMP response element. Mol Cell Endocrinol 2008; 285:51-61. [PMID: 18316157 PMCID: PMC2694994 DOI: 10.1016/j.mce.2008.01.016] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2007] [Revised: 01/14/2008] [Accepted: 01/23/2008] [Indexed: 12/22/2022]
Abstract
In endometrial adenocarcinomas COX-2 and F-series prostanoid (FP) receptor expression and prostanoid biosynthesis (PGE(2) and PGF(2alpha)) are elevated. In the present study, we investigated the effect of PGE(2) and PGF(2alpha) on the expression of COX-2 via the FP receptor in endometrial adenocarcinoma cells stably expressing the FP receptor (FPS cells). Using chemical inhibitors of intracellular signaling pathways, reporter gene assays and quantitative RT-PCR analysis, we show that PGE(2) and PGF(2alpha) can mobilize inositol 1,4,5-trisphosphate, induce ERK1/2 phosphorylation via the phospholipase Cbeta-protein kinase A-epidermal growth factor receptor pathway and induce cyclooxygenase-2 (COX-2) expression via the FP receptor. In addition we show that the PGE(2) or PGF(2alpha)-regulation of COX-2 via the FP receptor is mediated via the cAMP response element (CRE) binding site on the COX-2 promoter. These data indicate that PGE(2) and PGF(2alpha) biosynthesized locally within endometrial adenocarcinomas can regulate tumor cell function in an autocrine/paracrine manner via the FP receptor.
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MESH Headings
- Adenocarcinoma/metabolism
- Cell Line, Tumor
- Cyclooxygenase 2/genetics
- Cyclooxygenase 2/metabolism
- Dinoprost/analogs & derivatives
- Dinoprost/metabolism
- Dinoprostone/metabolism
- Endometrial Neoplasms/metabolism
- Enzyme Activation
- Enzyme Inhibitors/metabolism
- Extracellular Signal-Regulated MAP Kinases/metabolism
- Female
- Gene Expression Regulation, Enzymologic
- Genes, Reporter
- Humans
- Inositol 1,4,5-Trisphosphate/metabolism
- Promoter Regions, Genetic
- Prostaglandin Antagonists/metabolism
- Receptors, Prostaglandin/antagonists & inhibitors
- Receptors, Prostaglandin/genetics
- Receptors, Prostaglandin/metabolism
- Receptors, Prostaglandin E/metabolism
- Response Elements
- Signal Transduction/physiology
- Xanthones/metabolism
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Affiliation(s)
| | | | - Henry N. Jabbour
- Corresponding author. Tel.: +44 131 2426220; fax: +44 131 2426231.
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20
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Latli B, Krishnamurthy D, Senanayake C. Synthesis of tritium- and deuterium-labeled budesonide. J Labelled Comp Radiopharm 2008. [DOI: 10.1002/jlcr.1480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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21
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Boetkjaer A, Boedker M, Cui JG, Zhao Y, Lukiw WJ. Synergism in the repression of COX-2- and TNFalpha-induction in platelet activating factor-stressed human neural cells. Neurosci Lett 2007; 426:59-63. [PMID: 17881124 PMCID: PMC2083574 DOI: 10.1016/j.neulet.2007.08.050] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2007] [Revised: 08/14/2007] [Accepted: 08/15/2007] [Indexed: 11/25/2022]
Abstract
Platelet activating factor (PAF; beta-acetyl-gamma-O-hexadecyl-l-alpha-phosphatidylcholine) triggers a rapid pro-inflammatory gene expression program in primary cultures of human neural (HN) cells. Two genes and gene products consistently induced after PAF treatment are the cytosoluble prostaglandin synthase cycloooxygenase-2 (COX-2) and the pro-apoptotic tumor necrosis factor alpha (TNFalpha). Both of these mediators are associated with the activation of inflammatory signaling, neural cell dysfunction, apoptosis and brain cell death, and both have been found to be up-regulated after brain injury in vivo. In this study we investigated the effects of the non-halogenated synthetic glucocorticoid budesonide epimer R (BUDeR), the novel PAF antagonist LAU-0901, and the electron spin trap and free radical scavenger phenyl butyl nitrone (PBN), upon early COX-2 and TNFalpha gene activation and prostaglandin E(2) (PGE(2)) release in PAF-stressed primary HN cells. The data indicate that these three biochemically unrelated classes of inflammatory repressors act synergistically in modulating PAF-induced up-regulation of COX-2, TNFalpha, and PGE(2) by quenching oxidative stress or inflammatory signaling, resulting in increased HN cell survival. These, or analogous classes of compounds, may be useful in the design of more effective combinatorial pharmacotherapeutic strategies in the treatment of complex neuro-inflammatory disorders.
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Affiliation(s)
- Anja Boetkjaer
- The Danish University of Pharmaceutical Sciences, Universitetsparken 2, DK 2100 Copenhagen, Denmark
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22
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Woo KJ, Park JW, Kwon TK. Proteasome inhibitor-induced cyclooxygenase-2 expression in Raw264.7 cells is potentiated by inhibition of c-Jun N-terminal kinase activation. Biochem Biophys Res Commun 2006; 342:1334-40. [PMID: 16516846 DOI: 10.1016/j.bbrc.2006.02.105] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2006] [Accepted: 02/16/2006] [Indexed: 12/16/2022]
Abstract
Prostaglandins play regulatory roles in a variety of physiological and pathological processes in immune response and inflammation. MG132, proteasome inhibitor, is known to anti-tumor agent activity and anti-inflammation with inhibitory property of NF-kappaB. We investigated the effect of MG132 on the expression of cyclooxygenase-2 (COX-2), the rate-limiting enzyme in the synthesis of PGE(2), using macrophage cell line, Raw264.7. Our results showed that COX-2 expression is up-regulated by MG132 treatment and that this induction of COX-2 is regulated in part at the transcriptional level. In addition, we demonstrated the signal transduction pathway of mitogen-activated protein kinase (MAP kinase) in MG132-induced COX-2 expression. The p38 MAPK inhibitor (SB 203580) prevented MG132-induced COX-2 expression, whereas c-Jun N-terminal kinase (JNK) inhibitor (SP 600125) and MAPK kinase 4 (MKK4)-DN (dominant negative mutant) and MKK7-DN significantly enhanced COX-2 expression. These results suggest that MG132-induced COX-2 expression is associated with the activation of p38 MAPK and the inhibition of JNK signaling pathways.
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Affiliation(s)
- Kyung Jin Woo
- Department of Immunology, School of Medicine, Keimyung University, 194 DongSan-Dong Jung-Gu, Taegu 700-712, Republic of Korea
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23
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Kis K, Bodai L, Polyanka H, Eder K, Pivarcsi A, Duda E, Soos G, Bata-Csorgo Z, Kemeny L. Budesonide, but not tacrolimus, affects the immune functions of normal human keratinocytes. Int Immunopharmacol 2006; 6:358-68. [PMID: 16428071 DOI: 10.1016/j.intimp.2005.08.022] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2005] [Revised: 04/06/2005] [Accepted: 08/25/2005] [Indexed: 10/25/2022]
Abstract
Topical immunosuppressant therapy is widely used in the treatment of inflammatory skin diseases such as psoriasis and atopic dermatitis. Besides its beneficial therapeutic effects, application of topical anti-inflammatory drugs may render the epidermis more vulnerable to invading pathogens by suppressing innate immune responses in keratinocytes, such as cytokine production and Toll-like receptor (TLR) expression. In order to evaluate and compare the immunosuppressive effects of different immunosuppressant drugs on keratinocytes, we treated lipopolysaccharide (LPS)-stimulated and -unstimulated normal human keratinocytes with the synthetic corticosteroid budesonide and the macrolide tacrolimus. The expressions of the pattern recognition receptors (PRRs) TLR2 and TLR4 were measured by quantitative RT-PCR, pro-inflammatory cytokines IL-1alpha, IL-8 and TNF-alpha were monitored by quantitative RT-PCR and by ELISA, and alterations in TLR2 protein level were measured by flow cytometry. Budesonide had a suppressive effect on both constitutive and LPS-induced IL-8 gene expression. The amount of TNF-alpha mRNA was diminished in unstimulated keratinocytes, while TLR2 mRNA expression was markedly enhanced both in unstimulated and LPS-treated cells after incubation with budesonide. This increase in TLR2 mRNA expression was also detectable at the protein level in LPS-stimulated cells. Tacrolimus had no effect on any of the examined genes. Budesonide, but not tacrolimus, significantly inhibited the NF-kappaB-dependent luciferase reporter activity in HaCaT cells after induction with LPS or TNF-alpha. Although tacrolimus and budesonide are both effective treatments in some inflammatory skin diseases, the data provided here imply differences in local therapeutic and adverse effects of these two topical immunosuppressants.
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Affiliation(s)
- K Kis
- Department of Clinical Pharmacy, Faculty of Pharmacy, University of Szeged, Szeged, Hungary.
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24
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Boedker M, Boetkjaer A, Bazan NG, Cui JG, Zhao Y, Pelaez RP, Lukiw WJ. Budesonide epimer R, LAU-8080 and phenyl butyl nitrone synergistically repress cyclooxygenase-2 induction in [IL-1β+Aβ42]-stressed human neural cells. Neurosci Lett 2005; 380:176-80. [PMID: 15854773 DOI: 10.1016/j.neulet.2005.01.044] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2004] [Revised: 01/06/2005] [Accepted: 01/12/2005] [Indexed: 11/27/2022]
Abstract
Interleukin-1beta (IL-1beta) and amyloid-beta peptide 42 (Abeta42) together induce a robust proinflammatory gene expression program in human neural cells in primary culture. One consistent genetic marker for this triggered inflammatory response is an increase in the expression of cycloooxygenase-2 (COX-2), a prostaglandin synthase also found to be up-regulated in neurological disorders such as Alzheimer's disease. In this study we provide data illustrating the combined effect of three independent classes of compounds: the glucocorticoid budesonide epimer R, the platelet-activating factor antagonist LAU-8080, and the free radical scavenger phenyl butyl nitrone, upon COX-2 gene activation and prostaglandin E2 (PGE2) levels in [IL-1beta+Abeta42]-stressed HN cells. The data indicate that specific combinations of repressors of COX-2 activity are synergistic in modulating the stress-induced up-regulation of COX-2 and PGE2, and this may be of potential therapeutic value in the design of treatment for complex neuroinflammatory disorders.
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Affiliation(s)
- Merete Boedker
- Department of Pharmacology, The Danish University of Pharmaceutical Sciences, Universitetsparken 2, DK 2100 Copenhagen, Denmark
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25
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Zhang X, Shan P, Alam J, Fu XY, Lee PJ. Carbon monoxide differentially modulates STAT1 and STAT3 and inhibits apoptosis via a phosphatidylinositol 3-kinase/Akt and p38 kinase-dependent STAT3 pathway during anoxia-reoxygenation injury. J Biol Chem 2004; 280:8714-21. [PMID: 15590660 DOI: 10.1074/jbc.m408092200] [Citation(s) in RCA: 156] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Carbon monoxide (CO), previously considered a toxic waste product of heme catabolism, is emerging as an important gaseous molecule. In addition to its important role in neurotransmission, exogenous CO protects against vascular injury, transplant rejection, and acute lung injury. However, little is known regarding the precise signaling mechanisms of CO. We have recently shown that CO attenuates endothelial cell apoptosis during anoxia-reoxygenation injury by activating MKK3/p38alpha mitogen-activated protein kinase (MAPK) pathways. Our current study is the first to demonstrate that CO can differentially modulate STAT1 and STAT3 activation and, specifically, that STAT3 activation by CO is responsible for the anti-apoptotic effect in endothelial cells. In addition, we show that the anti-apoptotic effects of CO depend upon both phosphatidylinositol 3-kinase/Akt and p38 MAPK signaling pathways in endothelial cells, whereas previous reports have implicated only the MKK3/p38 MAPK pathway. Using chemical inhibitors and dominant negative constructs, we show that CO enhances STAT3 activation via phosphatidylinositol 3-kinase/Akt and p38 MAPK pathways with subsequent attenuation of Fas expression and caspase 3 activity. These data highlight the anti-apoptotic signaling mechanisms of CO and, importantly, delineate potential therapeutic strategies to prevent ischemia-reperfusion or anoxia-reoxygenation injury in the vasculature.
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Affiliation(s)
- Xuchen Zhang
- Section of Pulmonary & Critical Care Medicine, Yale University School of Medicine, New Haven, Connecticut 06520, USA
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26
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Murata H, Tsuji S, Tsujii M, Sakaguchi Y, Fu HY, Kawano S, Hori M. Promoter hypermethylation silences cyclooxygenase-2 (Cox-2) and regulates growth of human hepatocellular carcinoma cells. J Transl Med 2004; 84:1050-9. [PMID: 15156159 DOI: 10.1038/labinvest.3700118] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Cyclooxygenase-2 (COX-2) upregulation is recognized to confer advantage in progression in a wide variety of cancers, with colorectal cancer most intensively investigated. Epidemiologically, chemopreventive effects of COX-2 inhibitors have been proven on numerous cancers, but not on hepatocellular carcinoma (HCC). Although the antiapoptotic feature of COX-2 generally supports cancer cell growth, previous reports have shown that COX-2 expression, upregulated in early HCC, is downregulated in advanced HCC. Therefore, COX-2 downregulation may be somehow advantageous and specific for HCC development. However, its mechanism remains unclear. Since promoter hypermethylation often silences the gene expression, we hypothesized that the epigenetic mechanism might regulate COX-2 expression in HCC. We examined the methylation status of the Cox-2 promoter in six human HCC cell lines (Hep3B, HepG2, SK-Hep1, HuH7, PLC, and FLC-7 cells) using methylation-specific PCR. The promoter was remarkably hypermethylated in Hep3B and FLC-7 cells and moderately in HepG2 and SK-Hep1 cells, but not in HuH7 and PLC cells. In Hep3B cells, coincubation with 5-aza-2'-deoxycytidine, a demethylator, demethylated the promoter and upregulated COX-2 expression as well as prostaglandin E2 production dose dependently. On the other hand, no such effects were observed in HuH7 cells. Additionally, the methylator suppressed growth of Hep3B cells dose dependently, accompanied by cyclin D1 downregulation, and the growth suppression was abrogated by potent COX-2 inhibition with a COX-2 selective inhibitor celecoxib, but these responses were not found in HuH7 cells. These results indicated that cell growth was largely retarded by Cox-2 upregulation via promoter demethylation, rather than the potentially reactivated genes concurrently demethylated by 5-aza-2'-deoxycytidine. In conclusion, promoter hypermethylation transcriptionally silences Cox-2 in HCC cells. Epigenetic alteration of Cox-2, at least in part, modulates the growth of HCC cells.
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Affiliation(s)
- Hiroaki Murata
- Department of Internal Medicine and Therapeutics, School of Allied Health Sciences, Osaka University Graduate School of Medicine, Osaka, Japan
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27
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Bouayad A, Fouron JC, Hou X, Beauchamp M, Quiniou C, Abran D, Peri K, Clyman RI, Varma DR, Chemtob S. Developmental regulation of prostaglandin E2 synthase in porcine ductus arteriosus. Am J Physiol Regul Integr Comp Physiol 2004; 286:R903-9. [PMID: 14715488 DOI: 10.1152/ajpregu.00437.2003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The synthesis of PGE2, the major vasodilator prostanoid of the ductus arteriosus (DA), is catalyzed by PGE2 synthases (PGES). The factors implicated in increased PGE2 synthesis in the perinatal DA are not known. We studied the developmental changes of PGES along with that of cyclooxygenase (COX)-2 and cytosolic phospholipase A2 (cPLA2) in the DA of fetal (75-90% gestation) and immediately postnatal newborn (NB) piglets. Levels of microsomal PGES (mPGES), COX-2, and PGE2 in the DA of NB were ∼7-fold higher than in fetus; activities of cytosolic PGES (cPGES) and cPLA2 in DA of the fetus and NB did not differ. Because platelet-activating factor (PAF) could regulate COX-2 expression, the former was measured and found to be more abundant in the DA of the NB than of fetus. PAF elicited an increase in mPGES, COX-2, and PGE2 in fetal DA to levels approaching those of the NB; cPGES, cPLA2, and COX-1 were unaffected. In perinatal NB DA, PAF receptor antagonists BN-52021 and THG-315 reduced mPGES, COX-2, and PGE2 levels and were associated with increased DA tone. It is concluded that PAF contributes in regulating DA tone by governing mPGES, COX-2, and ensuing PGE2 levels in the perinate.
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Affiliation(s)
- Asmàa Bouayad
- FRCP(C) Research Center, Sainte-Justine Hospital, 3175 Côte Ste-Catherine, Montréal, Quebec H3T 1C5, Canada.
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28
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Kim SP, Park JW, Lee SH, Lim JH, Jang BC, Lee SH, Jang IH, Freund JN, Suh SI, Mun KC, Song DK, Ha EM, Lee WJ, Kwon TK. Homeodomain protein CDX2 regulates COX-2 expression in colorectal cancer. Biochem Biophys Res Commun 2004; 315:93-9. [PMID: 15013430 DOI: 10.1016/j.bbrc.2004.01.020] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2003] [Indexed: 12/27/2022]
Abstract
CDX2 is an intestine-specific tumor suppressor gene encoding homeodomain-containing transcription factor, which is involved in a variety of developmental, proliferating, and differentiating processes. Moreover, the expression of CDX2 is reduced in a subset of primary colorectal cancers. In contrast, cyclooxygenase-2 (COX-2) is often up-regulated in human colorectal cancers. However, the molecular relationship between CDX2 down-regulation and COX-2 up-regulation is unknown. Here we show that CDX2 down-regulates COX-2 promoter activity by interacting with NF-kappaB. The ectopic expression of CDX2 was found to suppress PMA-induced COX-2 promoter activity in a dose-dependent manner. In addition, the treatment of colorectal cancer cells with PMA resulted in significant reduction in the level of endogenous CDX2 and a significant increase in the level of endogenous COX-2, in a dose-dependent manner. Furthermore, CDX2 was found to co-immunoprecipitate with the p65 subunit of NF-kappaB and to inhibit p65-induced NF-kappaB minimal promoter activity in colon cancer cells. These results suggest that reduced CDX2 expression may be involved in colorectal carcinogenesis by enhancing NF-kappaB-mediated inflammatory genes such as COX-2.
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Affiliation(s)
- Sang-Pyo Kim
- Institute for Medical Science, Keimyung University School of Medicine, 194 DongSan-Dong Jung-Gu, Daegu 700-712, Republic of Korea
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Kim HY, Park EJ, Joe EH, Jou I. Curcumin suppresses Janus kinase-STAT inflammatory signaling through activation of Src homology 2 domain-containing tyrosine phosphatase 2 in brain microglia. THE JOURNAL OF IMMUNOLOGY 2004; 171:6072-9. [PMID: 14634121 DOI: 10.4049/jimmunol.171.11.6072] [Citation(s) in RCA: 230] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Curcumin has been strongly implicated as an anti-inflammatory agent, but the precise mechanisms of its action are largely unknown. In this study, we show that the inhibitory action of curcumin on Janus kinase (JAK)-STAT signaling can contribute to its anti-inflammatory activity in the brain. In both rat primary microglia and murine BV2 microglial cells, curcumin effectively suppressed the ganglioside-, LPS-, or IFN-gamma-stimulated induction of cyclooxygenase-2 and inducible NO synthase, important enzymes that mediate inflammatory processes. These anti-inflammatory effects appear to be due, at least in part, to the suppression of the JAK-STAT inflammatory signaling cascade. Curcumin markedly inhibited the phosphorylation of STAT1 and 3 as well as JAK1 and 2 in microglia activated with gangliosides, LPS, or IFN-gamma. Curcumin consistently suppressed not only NF binding to IFN-gamma-activated sequence/IFN-stimulated regulatory element, but also the expression of inflammation-associated genes, including ICAM-1 and monocyte chemoattractant protein 1, whose promoters contain STAT-binding elements. We further show that activation of Src homology 2 domain-containing protein tyrosine phosphatases (SHP)-2, a negative regulator of JAK activity, is likely to be one of the mechanisms underlying the curcumin-mediated inhibition of JAK-STAT signaling. Treatment of microglial cells with curcumin led to an increase in phosphorylation and association with JAK1/2 of SHP-2, which inhibit the initiation of JAK-STAT inflammatory signaling in activated microglia. Taken together, these data suggest curcumin suppresses JAK-STAT signaling via activation of SHP-2, thus attenuating inflammatory response of brain microglial cells.
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Affiliation(s)
- Hee Young Kim
- Department of Pharmacology, Ajou University Medical School, Suwon, Korea
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Krämer BK, Kammerl MC, Kömhoff M. Renal Cyclooxygenase-2 (Cox-2). Kidney Blood Press Res 2004; 27:43-62. [PMID: 14691350 DOI: 10.1159/000075811] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/07/2003] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND/AIMS The role of COX-2 for renal function during renal development, for physiology and pathophysiology of renal diseases and the side effects of available COX-2 inhibitors, has gained increasing interest. We aimed therefore to review the respective role of renal COX-2. METHODS Review of relevant recent publications in the field, and in addition of in part unpublished data obtained in our laboratories. RESULTS COX-2 is 'constitutively' localized in the kidney i.e. in macula densa, TALH, interstitial cells, and is of utmost importance for normal renal development. Renal COX-2 is regulated by for example sodium and volume intake, angiotensin II, glucocorticoids often involving specific COX-2 promotor response elements. COX-2 derived prostanoids are required for preservation of renal blood flow and glomerular filtration especially in states of fluid deficit, they promote natriuresis, and furthermore may stimulate renin secretion during low-sodium intake/loop diuretic use. Conversely, COX-2 inhibitors decrease glomerular filtration, and renal perfusion, sometimes even causing acute renal failure. In addition, COX-2 inhibitors cause sodium retention, edema formation, cardiac failure and hypertension. The role of COX-2 derived prostanoids in renal inflammation or failure including diabetic nephropathy and renal transplantation remains at present controversial. CONCLUSION COX-2 is one of the major players in renal physiology and pathophysiology. One focus of future work should be placed on COX-2 in primary renal diseases.
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Affiliation(s)
- Bernhard K Krämer
- Nephrologie, Klinik und Poliklinik für Innere Medizin II, Regensburg, Germany.
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31
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Kiritoshi S, Nishikawa T, Sonoda K, Kukidome D, Senokuchi T, Matsuo T, Matsumura T, Tokunaga H, Brownlee M, Araki E. Reactive oxygen species from mitochondria induce cyclooxygenase-2 gene expression in human mesangial cells: potential role in diabetic nephropathy. Diabetes 2003; 52:2570-7. [PMID: 14514642 DOI: 10.2337/diabetes.52.10.2570] [Citation(s) in RCA: 256] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Hyperglycemia increases the production of reactive oxygen species (ROS) from the mitochondrial electron transport chain in bovine endothelial cells. Because several studies have postulated a role for prostaglandins (PGs) in the glomerular hyperfiltration seen in early diabetes, we evaluated the effect of mitochondrial ROS on expression of the inducible isoform of cyclooxygenase (COX-2) in cultured human mesangial cells (HMCs). We first confirmed that incubation of HMC with 30 mmol/l glucose significantly increased COX-2 mRNA but not COX-1 mRNA, compared with 5.6 mmol/l glucose. Similarly, incubation of HMCs with 30 mmol/l glucose significantly increased mitochondrial membrane potential, intracellular ROS production, COX-2 protein expression, and PGE2 synthesis, and these events were completely suppressed by thenoyltrifluoroacetone or carbonyl cyanide m-chlorophenylhydrazone, inhibitors of mitochondrial metabolism, or by overexpression of uncoupling protein-1 or manganese superoxide dismutase. Furthermore, increased expression of COX-2 mRNA and protein was confirmed in glomeruli of streptozotocin-induced diabetic mice. In addition, hyperglycemia induced activation of the COX-2 gene promoter, which was completely abrogated by mutation of two nuclear factor kappaB (NF-kappaB) binding sites in the promoter region. Our results suggest that hyperglycemia increases mitochondrial ROS production, resulting in NF-kappaB activation, COX-2 mRNA induction, COX-2 protein production, and PGE2 synthesis. This chain of events might contribute to the pathogenesis of diabetic nephropathy.
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Affiliation(s)
- Shinsuke Kiritoshi
- Department of Metabolic Medicine, Kumamoto University School of Medicine, Honjo, Kumamoto, Japan
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De Bosscher K, Vanden Berghe W, Haegeman G. The interplay between the glucocorticoid receptor and nuclear factor-kappaB or activator protein-1: molecular mechanisms for gene repression. Endocr Rev 2003; 24:488-522. [PMID: 12920152 DOI: 10.1210/er.2002-0006] [Citation(s) in RCA: 621] [Impact Index Per Article: 29.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The inflammatory response is a highly regulated physiological process that is critically important for homeostasis. A precise physiological control of inflammation allows a timely reaction to invading pathogens or to other insults without causing overreaction liable to damage the host. The cellular signaling pathways identified as important regulators of inflammation are the signal transduction cascades mediated by the nuclear factor-kappaB and the activator protein-1, which can both be modulated by glucocorticoids. Their use in the clinic includes treatment of rheumatoid arthritis, asthma, allograft rejection, and allergic skin diseases. Although glucocorticoids have been widely used since the late 1940s, the molecular mechanisms responsible for their antiinflammatory activity are still under investigation. The various molecular pathways proposed so far are discussed in more detail.
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Affiliation(s)
- Karolien De Bosscher
- Department of Molecular Biology, Ghent University, K. L. Ledeganckstraat 35, 9000 Gent, Belgium
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33
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Riazanskaia N, Lukiw WJ, Grigorenko A, Korovaitseva G, Dvoryanchikov G, Moliaka Y, Nicolaou M, Farrer L, Bazan NG, Rogaev E. Regulatory region variability in the human presenilin-2 (PSEN2) gene: potential contribution to the gene activity and risk for AD. Mol Psychiatry 2003; 7:891-8. [PMID: 12232783 DOI: 10.1038/sj.mp.4001101] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2001] [Revised: 11/20/2001] [Accepted: 02/07/2002] [Indexed: 11/09/2022]
Abstract
We have analyzed the 5'-upstream promoter region of the presenilin 2 gene (PSEN2) for regulatory elements and examined Alzheimer disease (AD) patients and non-demented individuals for polymorphisms in the 5' upstream promoter region of the PSEN2 gene. Direct sequencing analysis detected a common single adenine (A) nucleotide deletion polymorphism in the upstream promoter region of the PSEN2 gene. Examination of cohorts of AD patients and age-matched control individuals revealed no statistically significant differences in the frequency of this polymorphism when compared with the total sample of AD patients and control individuals. However, subgroup and regression analysis suggested that the relatively rare -A/-A genotype increases risk of AD among subjects lacking apolipoprotein E (APOE) epsilon4 and among persons ages 65 years and younger. DNA sequence and DNA-protein binding analysis demonstrated that this mutation negates binding with putative repressor transcription factor (TF), interferon regulatory factor 2 (IRF2), in nuclear extracts prepared from the aged human brain neocortex. However this mutation creates a potential regulatory element, C/EBPbeta, that is responsive to pro-inflammatory (PI) induction. The expression activity assay with luciferase reporter gene into normal human neural progenitor cells in primary culture shows that the mutant PSEN2 regulatory region exhibits a 1.8-fold higher level of basal expression and is sensitive to IL-1beta and Abeta42, but that it is synergistically induced 3.2-fold over the wild-type PSEN2 by [IL-1beta+Abeta42]. These results suggest that under Pl and oxygen stress conditions relatively minor variations in PSEN2 promoter DNA sequence structure can enhance PSEN2 gene expression and that consequently these may play a role in the induction and/or proliferation of a Pl response in AD brain.
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Affiliation(s)
- N Riazanskaia
- Laboratory of Molecular Brain Genetics, Research Center of Mental Health, Russian Academy of Medical Sciences of Russia, Moscow 113152, Russia
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34
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Yamashita M, Ashino S, Oshima Y, Kawamura S, Ohuchi K, Takayanagi M. Inhibition of TPA-induced NF-kappaB nuclear translocation and production of NO and PGE2 by the anti-rheumatic gold compounds. J Pharm Pharmacol 2003; 55:245-51. [PMID: 12631417 DOI: 10.1211/002235702513] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Auranofin, aurothioglucose and aurothiomalate (10 microM each) inhibited 12-O-tetradecanoylphorbol 13-acetate (TPA, 16.2 nM)-induced nuclear translocation of nuclear factor-kappa B (NF-kappaB), and production of nitric oxide (NO) and prostaglandin E(2) (PGE(2)) in rat peritoneal macrophages when the cells were pre-incubated with each gold compound for 20 h. Without pre-incubation for 20 h, aurothioglucose and aurothiomalate, but not auranofin, failed to inhibit the TPA-induced NF-kappaB nuclear translocation and production of NO and PGE(2). Auranofin, aurothioglucose and aurothiomalate did not affect the direct binding of NF-kappaB to the DNA probe. It was suggested that these gold compounds inhibit the TPA-induced production of NO and PGE(2) by inhibiting the NF-kappaB nuclear translocation.
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Affiliation(s)
- Masamichi Yamashita
- Department of Pathophysiological Science, Tohoku Pharmaceutical University, 4-4-1 Komatsushima, Aoba-ku, Sendai, Miyagi 981-8558, Japan.
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35
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Roy Baker R, Chang HY. MgATP may depress de novo neuronal nuclear PAF generation by promoting the formation of alkylacylglycerophosphate, an inhibitor of alkylglycerophosphate acetyltransferase. BIOCHIMICA ET BIOPHYSICA ACTA 2002; 1585:44-9. [PMID: 12457714 DOI: 10.1016/s1388-1981(02)00318-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
MgATP substantially inhibited 1-alkyl-sn-glycero-3-phosphate (AGP) acetyltransferase found in neuronal nuclei. Other nucleotides and the ATP analogue AMP-PNP did not show a comparable inhibition. MgATP inhibition decreased in the presence of bovine serum albumin or the fatty acyl CoA synthetase inhibitor, Triacsin C. MgATP inhibition increased when nuclei were preincubated in 50 mM Tris-HCl (pH 7.4)/1 mM MgCl(2) at 37 degrees C, and preincubations elevated levels of nuclear free fatty acid. Exogenous free fatty acid, added to the acetylation incubations, increased the inhibition seen in the presence of MgATP. Oleoyl CoA, in the absence of MgATP, also inhibited AGP acetylation. These results suggested that MgATP supported the conversion of nuclear free fatty acids to fatty acyl CoA. Fatty acyl CoA may directly inhibit nuclear AGP acetyltransferase, but inhibition brought about by MgATP was competitive for the AGP substrate, suggesting an inhibitor close in structure to AGP. 1-Hexadecyl-2-arachidonoyl-sn-glycero-3-phosphate was identified as a competitive inhibitor for AGP in the acetylation reaction. Neuronal nuclei can convert AGP to 1-alkyl-2-acyl-sn-glycero-3-phosphate (AAcylGP), a reaction dependent upon MgATP and the presence of acetyl CoA or free CoA. This nuclear acylation was increased by free fatty acid addition and was seen using oleoyl CoA in the absence of MgATP. Nuclear AAcylGP formation was inhibited by bovine serum albumin and by Triacsin C. Thus, nuclear AGP acetyltransferase may be regulated by AGP acyltransferase activity and the availability of MgATP, a nucleotide that is rapidly lost during brain ischemia.
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Affiliation(s)
- R Roy Baker
- Department of Biochemistry, University of Toronto, Room 5202, Medical Sciences Building, 1 King's College Circle, M5S 1A8, Toronto, Ontario, Canada.
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36
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Bazan NG, Palacios-Pelaez R, Lukiw WJ. Hypoxia signaling to genes: significance in Alzheimer's disease. Mol Neurobiol 2002; 26:283-98. [PMID: 12428761 DOI: 10.1385/mn:26:2-3:283] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Aberrations in neural signaling, converging to and diverging from oxidative metabolism and blood supply, contribute to the initiation and maintenance of inflammatory responses, neuronal degeneration, and age-related cognitive decline in Alzheimer's disease (AD). Hypoxia/ischemia triggers phospholipase A2, leading to the accumulation of free arachidonic and docosahexaenoic acids (AA, DHA), as well as that of lysophospholipids. Some of these bioactive lipid messengers in turn give rise to several downstream lipid messengers, such as platelet-activating factor (PAF) and ecosanoids (prostaglandins and leukotrienes). Eicosanoid synthesis is highly regulated in hypoxia and in reperfusion subsequent to ischemia. As one of the consequences, mitochondrial function is disrupted and reactive oxygen species (ROS) both contribute to the expansion of cellular inflammatory responses and reduce the expression of genes required to maintain synaptic structure and function. On the other hand, pro-inflammatory genes are up-regulated. One of these, the inducible cyclooxygenase-2 (COX-2), along with oxygen-starved mitochondria, comprise the major sources of ROS in the brain during hypoxia, ischemia, and reperfusion. One outcome is a sustained metabolic stress that drives progressive dysfunction, apoptosis and/or necrosis, and brain cell death. How hypoxia modulates oxygen-sensitive gene expression is not well understood. Pro-inflammatory gene families that contribute to neurodegeneration are transiently activated in part by the heterodimeric oxygen-sensitive DNA-binding proteins nuclear factor for kappa B (NF-kappaB) and hypoxia-inducible factor-alpha (HIF-1alpha). Here the authors summarize current studies supporting the hypothesis that synaptically-derived lipid messengers play significant roles in ischemic stroke and that hypoxia is an important contributor to the onset and progression of AD neurodegeneration.
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Affiliation(s)
- Nicolas G Bazan
- Neuroscience Center and Department of Ophthalmology, Louisiana State University Health Sciences Center, New Orleans 70112-2272, USA
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37
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Bazan NG, Lukiw WJ. Cyclooxygenase-2 and presenilin-1 gene expression induced by interleukin-1beta and amyloid beta 42 peptide is potentiated by hypoxia in primary human neural cells. J Biol Chem 2002; 277:30359-67. [PMID: 12050157 DOI: 10.1074/jbc.m203201200] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Lipid messengers and amyloid beta (Abeta) peptides generated by cyclooxygenase-2 (COX-2) and presenilin-1 (PS1) mediate pro-inflammatory signaling and neural degeneration in Alzheimer's disease (AD) brain. This study provides data showing that the COX-2 and PS1 genes each transcribe rare, highly labile RNA species that display early response gene behavior in human neural (HN) cells in primary culture, down-regulation during human neural development, and up-regulation in AD neocortex and hippocampal CA1. Together, interleukin-1beta and amyloid beta42 peptide [IL-1beta+Abeta42] synergistically activated COX-2 and PS1 gene expression preceded by increases in AP1-, STAT1alpha-, and in particular NF-kappaBp50/p65- and HIF-1alpha-DNA binding. These events were markedly potentiated by hypoxia and blocked by the antioxidant alpha-phenyl-N-tert-butyl nitrone. Broad transcription profiling further indicated that hypoxia-induced, [IL-1beta+Abeta42]-treated HN cells display robust induction of COX-2 and PS1 as well as a pro-inflammatory gene family that includes NF-kappaBp50/p105, IL-1beta precursor, and cytosolic phospholipase A2 genes. These findings indicate a novel [IL-1beta+Abeta42]-mediated, hypoxia-enhanced, free radical-triggered gene program that drives inflammatory gene signaling and suggest a mechanism by which hypoxia during aging contributes episodically to amyloidogenesis, inflammation, and AD pathophysiology.
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Affiliation(s)
- Nicolas G Bazan
- Neuroscience Center and Department of Ophthalmology, Louisiana State University Health Sciences Center, New Orleans, Louisiana 70112-2272, USA
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38
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Shepard LW, Yang M, Xie P, Browning DD, Voyno-Yasenetskaya T, Kozasa T, Ye RD. Constitutive activation of NF-kappa B and secretion of interleukin-8 induced by the G protein-coupled receptor of Kaposi's sarcoma-associated herpesvirus involve G alpha(13) and RhoA. J Biol Chem 2001; 276:45979-87. [PMID: 11590141 DOI: 10.1074/jbc.m104783200] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The Kaposi's sarcoma herpesvirus (KSHV) open reading frame 74 encodes a G protein-coupled receptor (GPCR) for chemokines. Exogenous expression of this constitutively active GPCR leads to cell transformation and vascular overgrowth characteristic of Kaposi's sarcoma. We show here that expression of KSHV-GPCR in transfected cells results in constitutive transactivation of nuclear factor kappa B (NF-kappa B) and secretion of interleukin-8, and this response involves activation of G alpha(13) and RhoA. The induced expression of a NF-kappa B luciferase reporter was partially reduced by pertussis toxin and the G beta gamma scavenger transducin, and enhanced by co-expression of G alpha(13) and to a lesser extent, G alpha(q). These results indicate coupling of KSHV-GPCR to multiple G proteins for NF-kappa B activation. Expression of KSHV-GPCR led to stress fiber formation in NIH 3T3 cells. To examine the involvement of the G alpha(13)-RhoA pathway in KSHV-GPCR-mediated NF-kappa B activation, HeLa cells were transfected with KSHV-GPCR alone and in combination with the regulator of G protein signaling (RGS) from p115RhoGEF or a dominant negative RhoA(T19N). Both constructs, as well as the C3 exoenzyme from Clostritium botulinum, partially reduced NF-kappa B activation by KSHV-GPCR, and by a constitutively active G alpha(13)(Q226L). KSHV-GPCR-induced NF-kappa B activation is accompanied by increased secretion of IL-8, a function mimicked by the activated G alpha(13) but not by an activated G alpha(q)(Q209L). These results suggest coupling of KSHV-GPCR to the G alpha(13)-RhoA pathway in addition to other G proteins.
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Affiliation(s)
- L W Shepard
- Department of Pharmacology, College of Medicine, University of Illinois, Chicago, Illinois 60612, USA
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Ma X, Bazan HE. Platelet-activating factor (PAF) enhances apoptosis induced by ultraviolet radiation in corneal epithelial cells through cytochrome c-caspase activation. Curr Eye Res 2001; 23:326-35. [PMID: 11910521 DOI: 10.1076/ceyr.23.5.326.5445] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
PURPOSE To examine the role of platelet-activating factor (PAF) on apoptosis of corneal epithelial cells exposed to radiation. METHODS Rabbit corneal epithelial (RCE) and human corneal epithelial (HCE) cells were exposed to UVC radiation and then to carbamyl PAF (cPAF) for different increments of time. The PAF antagonist BN50739 was added 30 min before cPAF. The caspase inhibitors Ac-DEVD-CHO and Ac-YVAD-CHO were added 1 h before, and the phospholipase A(2) (PLA(2)) inhibitor MAFP was added 3 h before UVC irradiation. FITC-dUTP TUNEL and DAPI staining were performed to assess the percentage of apoptotic cells. DNA ladder analysis was used to investigate apoptosis induced by different intensities of UVC (50-600 J/m(2)) with or without cPAF. Caspase activation and release of cytochrome c from mitochondria to cytosol were determined by Western blot. RESULTS While only 2.7% of RCE cells were DAPI positive in controls incubated for 12 h, 44% of cells were stained positive 4 h after irradiation; these values increased to 63% in the presence of cPAF. Cells incubated with cPAF alone were similar to controls. TUNEL staining and DNA laddering showed also increased in apoptosis after PAF treatment of UV-irradiated cells and BN50739 blocked the effect of cPAF. cPAF increased caspase-3 activation induced by UV irradiation in HCE cells. Cytochrome c release from mitochondria to cytosol was observed 30 min after irradiation. cPAF almost doubled the release of cytochrome c at 30 min and 1 h. Here, too, BN50739 blocked the PAF effect. No release of cytochrome c by PAF was seen in non-irradiated cells, even at higher concentrations. MAFP caused a decrease in cytochrome c release from UV-treated cells, and caused an even greater inhibition of cytochrome c release in cells stimulated with PAF. CONCLUSIONS PAF increases RCE and HCE apoptosis caused by UV irradiation by stimulating PLA(2), producing an early release of cytocrome c from mitochondria and activating caspase-3 by a receptor-mediated mechanism. This accelerating effect of PAF on the apoptotic cascade only occurred when corneal epithelial cells had been previously damaged by UV radiation.
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Affiliation(s)
- X Ma
- Department of Ophthalmology and Neuroscience Center, LSU Health Sciences Center, New Orleans, Louisiana 70112, USA
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40
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Park JW, Choi YJ, Suh SI, Kwon TK. Involvement of ERK and protein tyrosine phosphatase signaling pathways in EGCG-induced cyclooxygenase-2 expression in Raw 264.7 cells. Biochem Biophys Res Commun 2001; 286:721-5. [PMID: 11520057 DOI: 10.1006/bbrc.2001.5415] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Prostaglandins play regulatory roles in a variety of physiological and pathological processes in immune response and inflammation. Epigallocatechin-3-gallate (EGCG) is known to potent antitumor agent with antioxidant property. We first investigated the effect of EGCG on the production of prostaglandin E(2) (PGE(2)) and the expression of cyclooxygenase-2 (COX-2), the rate-limiting enzyme in the synthesis of PGE(2), using macrophage cell line, Raw264.7. Our results showed that COX-2 expression and PGE(2) production are upregulated by EGCG treatment and that this induction of COX-2 is regulated in part at the transcriptional level. In addition, we demonstrated the signal transduction pathway of mitogen-activated protein kinase (MAP kinase) in EGCG-mediated COX-2 expression. The MEK inhibitor (PD098059) prevented EGCG-induced COX-2 expression, whereas sodium orthovanadate (protein-tyrosine phosphatase inhibitor) significantly enhanced COX-2 expression and PGE(2) production. These results suggest that EGCG mediated COX-2 expression and PGE(2) production is associated with the activation of both the ERK and protein-tyrosine phosphatase signaling pathways.
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Affiliation(s)
- J W Park
- Department of Immunology, School of Medicine, Keimyung University, 194 DongSan-Dong Jung-Gu, Taegu, 700-712, South Korea
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41
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Gupta RA, Polk DB, Krishna U, Israel DA, Yan F, DuBois RN, Peek RM. Activation of peroxisome proliferator-activated receptor gamma suppresses nuclear factor kappa B-mediated apoptosis induced by Helicobacter pylori in gastric epithelial cells. J Biol Chem 2001; 276:31059-66. [PMID: 11397815 DOI: 10.1074/jbc.m104141200] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Helicobacter pylori colonization leads to epithelial cell hyperproliferation within inflamed mucosa, but levels of apoptosis vary, suggesting that imbalances between rates of cell production and loss may contribute to differences in gastric cancer risk among infected populations. Peroxisome proliferator-activated receptor gamma (PPARgamma) regulates inflammatory and growth responses of intestinal epithelial cells. We determined whether activation of PPARgamma modified H. pylori-induced apoptosis in gastric epithelial cells. PPARgamma was expressed and functionally active in gastric epithelial cell lines sensitive to H. pylori-induced apoptosis. PPARgamma ligands 15d-PGJ(2) and BRL-49653 significantly attenuated H. pylomicronri-induced apoptosis, effects that could be reversed by co-treatment with a specific PPARgamma antagonist. Cyclopentanone prostaglandins that do not bind and activate PPARgamma had no effects on H. pylori-induced apoptosis. The ability of H. pylori to activate nuclear factor (NF)-kappaB and increase levels of the NF-kappaB target IL-8 was blocked by co-treatment with PPARgamma agonists, and direct inhibition of NF-kappaB also abolished H. pylori-stimulated apoptosis. These results suggest that activation of the PPARgamma pathway attenuates the ability of H. pylori to induce NF-kappaB-mediated apoptosis in gastric epithelial cells. Because PPARgamma regulates a multitude of host responses, activation of this receptor may contribute to varying levels of cellular turnover as well as the diverse pathologic outcomes associated with chronic H. pylori colonization.
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Affiliation(s)
- R A Gupta
- Divisions of Gastroenterology and Pediatric Gastroenterology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, USA
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Guo YS, Hellmich MR, Wen XD, Townsend CM. Activator protein-1 transcription factor mediates bombesin-stimulated cyclooxygenase-2 expression in intestinal epithelial cells. J Biol Chem 2001; 276:22941-7. [PMID: 11292836 DOI: 10.1074/jbc.m101801200] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Colorectal carcinogenesis is a complex, multistep process involving genetic alterations and progressive changes in signaling pathways regulating intestinal epithelial cell proliferation, differentiation, and apoptosis. Although cyclooxygenase-2 (COX-2), gastrin-releasing peptide (GRP), and its receptor, GRP-R, are not normally expressed by the epithelial cells lining the human colon, the levels of all three proteins are aberrantly overexpressed in premalignant adenomatous polyps and colorectal carcinomas of humans. Overexpression of these proteins is associated with altered epithelial cell growth, adhesion, and tumor cell invasiveness, both in vitro and in vivo; however, a mechanistic link between GRP-R-mediated signaling pathways and increased COX-2 overexpression has not been established. We report that bombesin, a homolog of GRP, potently stimulates the expression of COX-2 mRNA and protein as well as the release of prostaglandin E(2) from a rat intestinal epithelial cell line engineered to express GRP-R. Bombesin stimulation of COX-2 expression requires an increase in [Ca(2+)](i), activation of extracellular signal-regulated kinase (ERK)-1 and -2 and p38(MAPK), and increased activation and expression of the transcription factors Elk-1, ATF-2, c-Fos, and c-Jun. These data suggest that the expression of GRP-R in intestinal epithelial cells may play a role in carcinogenesis by stimulating COX-2 overexpression through an activator protein-1-dependent pathway.
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Affiliation(s)
- Y S Guo
- Departments of Surgery and Physiology and Biophysics, University of Texas Medical Branch, Galveston, Texas 77555, USA
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Lukiw WJ, Gordon WC, Rogaev EI, Thompson H, Bazan NG. Presenilin-2 (PS2) expression up-regulation in a model of retinopathy of prematurity and pathoangiogenesis. Neuroreport 2001; 12:53-7. [PMID: 11201091 DOI: 10.1097/00001756-200101220-00019] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Presenilin-2 (PS2; AD4), a regulator of intercellular signaling during CNS development and cell fate determination, appears to be involved in pathogenic processing of beta-amyloid precursor protein (betaAPP) into potentially neurotoxic beta-amyloid (Abeta) peptides. The PS2 gene promoter contains multiple DNA binding sites for the relatively rare hypoxia-inducible transcription factor HIF-1, suggesting that PS2 expression may be a sensitive indicator of decreased oxygen availability. We have used a cycled hypoxia/hyperoxia (10-50% O2) protocol followed by normoxia (20% O2) as a retinal model of retinopathy of prematurity to induce neovascularization (NV) in rat pups. Retinal cell nuclear extracts from pups undergoing hypoxia exhibited a dramatic increase in HIF-1-DNA binding, followed by a delayed (2-7 day) elevation of PS2 RNA message and protein. PS2 gene activation during hypoxia may direct cellular fate towards pathoangiogenesis and intercellular PS2-mediated signaling dysfunction.
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Affiliation(s)
- W J Lukiw
- Neuroscience Center and Department of Ophthalmology, Louisiana State University School of Medicine, New Orleans 70112-2272, USA
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Baker RR, Chang HY. The regulation of CoA-independent transacylation reactions in neuronal nuclei by lysophospholipid, free fatty acid, and lysophospholipase: the control of nuclear lyso platelet-activating factor metabolism. Mol Cell Biochem 2000; 215:135-44. [PMID: 11204449 DOI: 10.1023/a:1026535611654] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
CoA-independent transacylase activities generating alkylacylglycerophosphocholine (AAGPC) from alkylglycerophosphocholine (1-alkyl GPC) were considerably enriched in neuronal nuclei isolated from rabbit cerebral cortex. Specific nuclear transacylation activities were 13 times the corresponding microsomal values. Several lysophospholipids, notably 1-acyl glycerophosphocholine (1-acyl GPC), 1-alkenyl GPC and 1-alkenyl GPE (1-alkenyl glycerophosphoethanolamine) inhibited the transacylation of 1-alkyl GPC. The inhibitory effects of 1-acyl GPC were seen in the presence of MAFP (methyl arachidonoylfluorophosphonate) or free oleate, compounds that inhibit neuronal nuclear lysophospholipase. When neuronal nuclei were preincubated with 1-alkyl GPC, the radioactive AAGPC product served as donor in transacylation reactions, to generate 1-alkyl GPC. In these nuclear reactions, 1-palmitoyl GPE and 1-palmitoyl GPC appeared to be poor acceptor substrates, when compared with corresponding 1-alkyl and 1-alkenyl analogues. The presence of free oleate or MAFP in the reactions containing 1-acyl GPC boosted the release of 1-alkyl GPC from AAGPC. These observations are of particular relevance to brain ischemia in which lysophospholipid, free fatty acid, and platelet-activating factor (PAF) levels rise dramatically. PAF can be made by the nuclear acetylation of 1-alkyl GPC, which is formed by nuclear transacylation mechanisms. Yet transacylase also removes 1-alkyl GPC, and thus this enzyme activity can regulate 1-alkyl GPC availability. Our observations indicate that lysophospholipids promote the formation of 1-alkyl GPC from nuclear AAGPC via transacylation, while free fatty acid likely prolongs the lifetime of 1-acyl lysophospholipids substrates by lysophospholipase inhibition. Similarly, once 1-alkyl GPC is formed, other lysophospholipids effectively compete with this 1-alkyl analogue and reduce its conversion back to AAGPC by transacylation. Free oleate, in this case, sustains 1-acyl lysophospholipid inhibitors of 1-alkyl GPC transacylation. Thus the cycle of transacylation may favour 1-alkyl GPC formation during ischemia, increasing levels of 1-alkyl GPC for nuclear acetylation reactions and PAF formation. The nuclear generation of PAF is of considerable importance as PAF can play regulatory roles in transcription events associated with inflammation.
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Affiliation(s)
- R R Baker
- Department of Biochemistry, University of Toronto, Ontario, Canada
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Quinn JH, Kent JH, Moise A, Lukiw WJ. Cyclooxygenase-2 in synovial tissue and fluid of dysfunctional temporomandibular joints with internal derangement. J Oral Maxillofac Surg 2000; 58:1229-32; discussion 1232-3. [PMID: 11078133 DOI: 10.1053/joms.2000.16619] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE This study investigated cyclooxygenase-2 (COX-2) gene expression in temporomandibular joint (TMJ) synovial tissue and fluid from patients with internal derangement. PATIENTS AND METHODS Seventeen synovial tissue biopsy specimens and 16 synovial fluid samples were obtained from patients (1 male and 11 female) during arthroscopic TMJ surgery. The samples were frozen at -70 degrees C and, by using Northern and reverse transcription polymerase chain reaction (RT-PCR) analysis, the levels of COX-2 RNA in relation to beta-actin RNA message levels were determined. RESULTS COX-2 RNA message was detected in 16 of 17 synovial tissue samples (94%) and 12 of 16 synovial fluid samples (75%) by using beta-actin RNA levels in the same sample (either tissue or fluid) as an internal control. Samples were not quantified because of the same sample mass. CONCLUSION COX-2, an important inflammatory mediator, is present in the TMJ synovial tissue and fluid from patients with internal derangement. Therefore, COX-2 antagonists may be indicated in the treatment of TMJ arthralgia.
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Affiliation(s)
- J H Quinn
- LSU School of Dentistry, New Orleans, LA, USA
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Abstract
Alzheimer's disease (AD) is a progressive, neurodestructive process of the human neocortex, characterized by the deterioration of memory and higher cognitive function. A progressive and irreversible brain disorder, AD is characterized by three major pathogenic episodes involving (a) an aberrant processing and deposition of beta-amyloid precursor protein (betaAPP) to form neurotoxic beta-amyloid (betaA) peptides and an aggregated insoluble polymer of betaA that forms the senile plaque, (b) the establishment of intraneuronal neuritic tau pathology yielding widespread deposits of agyrophilic neurofibrillary tangles (NFT) and (c) the initiation and proliferation of a brain-specific inflammatory response. These three seemingly disperse attributes of AD etiopathogenesis are linked by the fact that proinflammatory microglia, reactive astrocytes and their associated cytokines and chemokines are associated with the biology of the microtubule associated protein tau, betaA speciation and aggregation. Missense mutations in the presenilin genes PS1 and PS2, implicated in early onset familial AD, cause abnormal betaAPP processing with resultant overproduction of betaA42 and related neurotoxic peptides. Specific betaA fragments such as betaA42 can further potentiate proinflammatory mechanisms. Expression of the inducible oxidoreductase cyclooxygenase-2 and cytosolic phospholipase A2 (cPLA2) are strongly activated during cerebral ischemia and trauma, epilepsy and AD, indicating the induction of proinflammatory gene pathways as a response to brain injury. Neurotoxic metals such as aluminum and zinc, both implicated in AD etiopathogenesis, and arachidonic acid, a major metabolite of brain cPLA2 activity, each polymerize hyperphosphorylated tau to form NFT-like bundles. Further, epidemiological and longitudinal studies have identified a reduced risk for AD in patients (<70 yrs) previously treated with non-steroidal anti-inflammatory drugs for non-CNS afflictions that include arthritis. This review will focus on the interrelationships between the mechanisms of PS1, PS2 and betaAPP gene expression, tau and betaA deposition and the induction, regulation and proliferation in AD of the neuroinflammatory response. Novel therapeutic interventions in AD are discussed.
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Affiliation(s)
- W J Lukiw
- Neuroscience Center and Department of Ophthalmology, New Orleans 70112-2272, USA
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Abstract
After more than a century of use, pharmacologists thought they had discovered the mechanism of action of nonsteroidal anti-inflammatory drugs (NSAIDs) when their inhibitory action on the production of prostaglandins was described. This action was located at the inhibition of the enzyme responsible for the conversion of arachidonic acid to prostaglandins, namely cyclo-oxygenase. More recently, it has been recognized that more than one isoform of the enzyme exists. The two forms of cyclo-oxygenase described are widely different in their location, activity, and role, especially because the COX-1 isoenzyme seems to be mainly a constitutive enzyme whereas the COX-2 isoenzyme is inducible. This separation of activity appears to be correlated with the separation of function of the various prostaglandins, whereas the constitutive form is associated with "physiologic" functions and the inducible form with inflammatory responses. Recent advances have included the development of drugs with a high specificity toward the inducible enzyme (COX-2) to focus on the anti-inflammatory actions, because many of the unwanted side effects of NSAIDs have been associated with inhibition of the constitutive isoform (COX-1). Other recent developments in studies of the NSAIDs have included potential therapeutic actions in other degenerative conditions.
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Affiliation(s)
- A Livingston
- Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada
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Abstract
Adjuvant analgesics are drugs that have weak or nonexistent analgesic action when administered alone but can enhance analgesic actions when coadministered with known analgesic agents. Such agents are often administered in cases of refractory pain. For some chronic pain syndromes, however, they may constitute a first-line approach. Because pain is such an individual experience, analgesic regimens may require several drugs at varying dosages to confer a comfortable state. Adjunctive therapies such as the tricyclic antidepressants, anticonvulsants, N-methyl-D-aspartic acid receptor antagonists and low-dose intravenous local anesthetics, to name a few, have proved to be efficacious in relieving certain types of pain, especially neuropathic and cancer pain. Their use in animals is increasing, with anecdotal reports of some success.
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Affiliation(s)
- L A Lamont
- Department of Veterinary Clinical Medicine, College of Veterinary Medicine, University of Illinois, Urbana, USA
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Affiliation(s)
- R M Schmid
- Department of Internal Medicine I, University of Ulm, Ulm, Germany.
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Abstract
In this review properties of lipid acetyltransferase enzymes are outlined. The three activities of interest are lyso PAF acetyltransferase (acetyl CoA: 1-alkyl-sn-glycero-3-phosphocholine acetyltransferase), AGP acetyltransferase (acetyl CoA: 1-alkyl sn-glycero-3-phosphate acetyltransferase) and a transacetylase activity that can transfer acetyl groups from PAF to lipid acceptors in the formation of 1-alkenyl-2-acetyl-sn-glycero-3-phosphoethanolamine and N-acetyl sphingosine (C2 ceramide). This review focuses on the role of acetyltransferases and transacetylases within the metabolism of platelet-activating factor and specifically addresses characteristics of the enzymes, including subcellular localization, substrate selectivity, and enzymatic regulation.
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Affiliation(s)
- R R Baker
- Department of Biochemistry, University of Toronto, Canada
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