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Sluter MN, Li Q, Yasmen N, Chen Y, Li L, Hou R, Yu Y, Yang CY, Meibohm B, Jiang J. The inducible prostaglandin E synthase (mPGES-1) in neuroinflammatory disorders. Exp Biol Med (Maywood) 2023; 248:811-819. [PMID: 37515545 PMCID: PMC10468642 DOI: 10.1177/15353702231179926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/31/2023] Open
Abstract
The cyclooxygenase (COX)/prostaglandin E2 (PGE2) signaling pathway has emerged as a critical target for anti-inflammatory therapeutic development in neurological diseases. However, medical use of COX inhibitors in the treatment of various neurological disorders has been limited due to well-documented cardiovascular and cerebrovascular complications. It has been widely proposed that modulation of downstream microsomal prostaglandin E synthase-1 (mPGES-1) enzyme may provide more specificity for inhibiting PGE2-elicited neuroinflammation. Heightened levels of mPGES-1 have been detected in a variety of brain diseases such as epilepsy, stroke, glioma, and neurodegenerative diseases. Subsequently, elevated levels of PGE2, the enzymatic product of mPGES-1, have been demonstrated to modulate a multitude of deleterious effects. In epilepsy, PGE2 participates in retrograde signaling to augment glutamate release at the synapse leading to neuronal death. The excitotoxic demise of neurons incites the activation of microglia, which can become overactive upon further stimulation by PGE2. A selective mPGES-1 inhibitor was able to reduce gliosis and the expression of proinflammatory cytokines in the hippocampus following status epilepticus. A similar mechanism has also been observed in stroke, where the overactivation of microglia by PGE2 upregulated the expression and secretion of proinflammatory cytokines. This intense activation of neuroinflammatory processes triggered the secondary injury commonly observed in stroke, and blockade of mPGES-1 reduced infarction size and edema, suppressed induction of proinflammatory cytokines, and improved post-stroke well-being and cognition. Furthermore, elevated levels of PGE2 have been shown to intensify the proliferation of glioma cells, mediate P-glycoprotein expression at the blood-brain barrier (BBB) and facilitate breakdown of the BBB. For these reasons, targeting mPGES-1, the central and inducible enzyme of the COX cascade, may provide a more specific therapeutic strategy for treating neuroinflammatory diseases.
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Affiliation(s)
| | | | | | | | | | - Ruida Hou
- Department of Pharmaceutical Sciences, College of Pharmacy, The University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Ying Yu
- Department of Pharmaceutical Sciences, College of Pharmacy, The University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Chao-Yie Yang
- Department of Pharmaceutical Sciences, College of Pharmacy, The University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Bernd Meibohm
- Department of Pharmaceutical Sciences, College of Pharmacy, The University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Jianxiong Jiang
- Department of Pharmaceutical Sciences, College of Pharmacy, The University of Tennessee Health Science Center, Memphis, TN 38163, USA
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2
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Sluter M, Bhuniya R, Yuan X, Ramaraju A, Chen Y, Yu Y, Parmar KR, Temrikar ZH, Srivastava A, Meibohm B, Jiang J, Yang CY. Novel, Brain-Permeable, Cross-Species Benzothiazole Inhibitors of Microsomal Prostaglandin E Synthase-1 (mPGES-1) Dampen Neuroinflammation In Vitro and In Vivo. ACS Pharmacol Transl Sci 2023; 6:587-599. [PMID: 37082746 PMCID: PMC10111624 DOI: 10.1021/acsptsci.2c00241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Indexed: 04/22/2023]
Abstract
Microsomal prostaglandin E synthase-1 (mPGES-1) is an inducible enzyme of the cyclooxygenase (COX) cascade that generates prostaglandin E2 (PGE2) during inflammatory conditions. PGE2 is known to be a potent immune signaling molecule that mediates both peripheral and central inflammations. Inhibition of mPGES-1, rather than COX, may overcome the cardiovascular side effects associated with long-term COX inhibition by providing a more specific strategy to target inflammation. However, mPGES-1 inhibitor development is hampered by the large differences in cross-species activity due to the structural differences between the human and murine mPGES-1. Here, we report that our thiazole-based mPGES-1 inhibitors, compounds 11 (UT-11) and 19 derived from two novel scaffolds, were able to suppress PGE2 production in human (SK-N-AS) and murine (BV2) cells. The IC50 values of inhibiting PGE2 production in human and murine cells were 0.10 and 2.00 μM for UT-11 and 0.43 and 1.55 μM for compound 19, respectively. Based on in vitro and in vivo pharmacokinetic data, we selected UT-11 for evaluation in a lipopolysaccharide (LPS)-induced inflammation model. We found that our compound significantly suppressed proinflammatory cytokines and chemokines in the hippocampus but not in the kidney. Taken together, we demonstrated the potential of UT-11 in treating neuroinflammatory conditions, including epilepsy and stroke, and warrant further optimization.
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Affiliation(s)
- Madison
N. Sluter
- Departments
of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee 38163, United States
- College
of Graduate Health Sciences, University
of Tennessee Health Science Center, Memphis, Tennessee 38163, United States
| | - Rajib Bhuniya
- Departments
of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee 38163, United States
| | - Xinrui Yuan
- Departments
of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee 38163, United States
| | - Andhavaram Ramaraju
- Departments
of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee 38163, United States
| | - Yu Chen
- Departments
of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee 38163, United States
| | - Ying Yu
- Departments
of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee 38163, United States
| | - Keyur R. Parmar
- Departments
of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee 38163, United States
| | - Zaid H. Temrikar
- Departments
of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee 38163, United States
| | - Ashish Srivastava
- Departments
of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee 38163, United States
| | - Bernd Meibohm
- Departments
of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee 38163, United States
| | - Jianxiong Jiang
- Departments
of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee 38163, United States
| | - Chao-Yie Yang
- Departments
of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee 38163, United States
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3
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Pinto MJ, Cottin L, Dingli F, Laigle V, Ribeiro LF, Triller A, Henderson F, Loew D, Fabre V, Bessis A. Microglial TNFα orchestrates protein phosphorylation in the cortex during the sleep period and controls homeostatic sleep. EMBO J 2023; 42:e111485. [PMID: 36385434 PMCID: PMC9811617 DOI: 10.15252/embj.2022111485] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 10/04/2022] [Accepted: 10/11/2022] [Indexed: 11/18/2022] Open
Abstract
Sleep intensity is adjusted by the length of previous awake time, and under tight homeostatic control by protein phosphorylation. Here, we establish microglia as a new cellular component of the sleep homeostasis circuit. Using quantitative phosphoproteomics of the mouse frontal cortex, we demonstrate that microglia-specific deletion of TNFα perturbs thousands of phosphorylation sites during the sleep period. Substrates of microglial TNFα comprise sleep-related kinases such as MAPKs and MARKs, and numerous synaptic proteins, including a subset whose phosphorylation status encodes sleep need and determines sleep duration. As a result, microglial TNFα loss attenuates the build-up of sleep need, as measured by electroencephalogram slow-wave activity and prevents immediate compensation for loss of sleep. Our data suggest that microglia control sleep homeostasis by releasing TNFα which acts on neuronal circuitry through dynamic control of phosphorylation.
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Affiliation(s)
- Maria J Pinto
- Institut de Biologie de l'École normale supérieure (IBENS), École normale supérieure, CNRS, INSERMUniversité PSLParisFrance
| | - Léa Cottin
- Institut de Biologie de l'École normale supérieure (IBENS), École normale supérieure, CNRS, INSERMUniversité PSLParisFrance
| | - Florent Dingli
- Centre de Recherche, Laboratoire de Spectrométrie de Masse ProtéomiqueInstitut Curie, PSL Research UniversityParisFrance
| | - Victor Laigle
- Centre de Recherche, Laboratoire de Spectrométrie de Masse ProtéomiqueInstitut Curie, PSL Research UniversityParisFrance
| | - Luís F Ribeiro
- Center for Neuroscience and Cell Biology (CNC), Institute for Interdisciplinary Research (IIIUC)University of CoimbraCoimbraPortugal
| | - Antoine Triller
- Institut de Biologie de l'École normale supérieure (IBENS), École normale supérieure, CNRS, INSERMUniversité PSLParisFrance
| | - Fiona Henderson
- Sorbonne Université, CNRS UMR 8246, INSERM U1130, Neuroscience Paris Seine – Institut de Biologie Paris Seine (NPS – IBPS)ParisFrance
| | - Damarys Loew
- Centre de Recherche, Laboratoire de Spectrométrie de Masse ProtéomiqueInstitut Curie, PSL Research UniversityParisFrance
| | - Véronique Fabre
- Sorbonne Université, CNRS UMR 8246, INSERM U1130, Neuroscience Paris Seine – Institut de Biologie Paris Seine (NPS – IBPS)ParisFrance
| | - Alain Bessis
- Institut de Biologie de l'École normale supérieure (IBENS), École normale supérieure, CNRS, INSERMUniversité PSLParisFrance
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4
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Kim SS, Won S, Lee HE, Ryu SH, Choi DJ, Cho SI, Gwag BJ, Youn HY, Lee JH. Potent Analgesic Action of 2-acetoxy-5-(2-4 (trifluoromethyl)-phenethylamino)-benzoic Acid (Flusalazine) in Experimental Mice. J Pain Res 2022; 15:3869-3879. [PMID: 36531829 PMCID: PMC9748189 DOI: 10.2147/jpr.s385617] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 11/25/2022] [Indexed: 11/26/2023] Open
Abstract
PURPOSE Nonsteroidal anti-inflammatory drugs (NSAIDs) and cyclooxygenase (COX)-2 selective inhibitors are the most widely used drugs to treat pain. Conventional NSAIDs and COX-2 selective inhibitors, however, cause several side effects such as gastric damage, kidney damage, and cardiovascular problems. Our previous study showed that 2-acetoxy-5-(2-4-(trifluoromethyl)-phenethylamino)-benzoic acid ie, flusalazine (also known as ND-07), which exerts dual actions by serving both as an anti-inflammatory agent and a free radical scavenger, is an effective and safe treatment for severe inflammatory diseases in mice. The goal of the present study was to examine the potential analgesic action and safety of flusalazine in mice models of pain. METHODS AND RESULTS Flusalazine showed a significant analgesic effect in an acetic acid-induced abdominal constriction model. Likewise, total paw licking was reduced significantly in neurogenic (early stage) and inflammatory (late stage) pain induced by formalin in flusalazine-treated mice. In the tail immersion test, flusalazine significantly increased tail withdrawal time at 2 h after its administration. Also, the formation of paw edema in the flusalazine-treated group was significantly inhibited in a carrageenan-induced inflammatory pain model. Gastric damage was not induced by flusalazine even up to 1000 mg/kg, while aspirin and indomethacin caused critical gastric bleeding. CONCLUSION These findings suggest that flusalazine's safety profile and analgesic effects have high translational potential for the clinical treatment of patients experiencing pain.
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Affiliation(s)
- Sung-Soo Kim
- VIP Animal Medical Center KR, Seoul, 02830, Republic of Korea
| | - Sojung Won
- GNT Pharma, Yongin, Gyeonggi, 17096, Republic of Korea
| | - Ha Eun Lee
- GNT Pharma, Yongin, Gyeonggi, 17096, Republic of Korea
| | | | | | - Sung Ig Cho
- GNT Pharma, Yongin, Gyeonggi, 17096, Republic of Korea
| | | | - Hwa-Young Youn
- Laboratory of Veterinary Internal Medicine, College of Veterinary Medicine, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jin Hwan Lee
- GNT Pharma, Yongin, Gyeonggi, 17096, Republic of Korea
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5
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Nagano T, Tsuda N, Fujimura K, Ikezawa Y, Higashi Y, Kimura SH. Prostaglandin E 2 increases the expression of cyclooxygenase-2 in cultured rat microglia. J Neuroimmunol 2021; 361:577724. [PMID: 34610503 DOI: 10.1016/j.jneuroim.2021.577724] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 09/17/2021] [Accepted: 09/19/2021] [Indexed: 12/21/2022]
Abstract
Prostaglandin E2 (PGE2) plays pivotal roles in controlling microglial activation with the EP2 receptor, a PGE2 receptor subtype. Activated microglia are often reported to increase cyclooxygenase (COX)-2 expression, followed by PGE2 production, but it is unclear whether extracellular PGE2 is involved in microglial PGE2 synthesis. In the present study, we report that PGE2 increases COX-2 protein in microglia. In a culture system, PGE2 at 10-6 M for 3 h increased COX-2 and microsomal PGE synthase (mPGES)-1 mRNA levels, and reduced mPGES-2, but did not affect COX-1 or cytosolic PGE synthase (cPGES) in microglia. PGE2 at 10-6 M for 3 h also increased the COX-2 protein level, but did not affect COX-1, mPGES-1, mPGES-2, or cPGES. An EP2 agonist, ONO-AE1-259-01, also increased COX-2 and mPGES-1 mRNA levels, and reduced mPGES-2, but did not affect COX-1 or cPGES, whereas an EP1 agonist, ONO-DI-004, an EP3 agonist, ONO-AE-248, and an EP4 agonist, ONO-AE1-329, had no effect. Similar to PGE2, ONO-AE1-259-01 increased the COX-2 protein level, but did not affect COX-1, mPGES-1, mPGES-2, or cPGES. In addition, the effects of PGE2 were inhibited by an EP2 antagonist, PF-04418948, but not by an EP1 antagonist, ONO-8713, an EP3 antagonist, ONO-AE3-240, or an EP4 antagonist, ONO-AE3-208, at 10-6 M. On the other hand, lipopolysaccharide (LPS) increased PGE2 production, but the LPS-induced PGE2 production was not affected by ONO-8713, PF-04418948, ONO-AE3-240, or ONO-AE3-208. These results indicate that PGE2 increases COX-2 protein in microglia through the EP2 receptor supporting the idea that extracellular PGE2 has a triggering aspect for microglial activation.
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Affiliation(s)
- Takayuki Nagano
- Department of Pharmacology, Hyogo College of Medicine, Nishinomiya, Hyogo, Japan.
| | - Naohiko Tsuda
- Department of Pharmacology, Hyogo College of Medicine, Nishinomiya, Hyogo, Japan
| | - Kenichi Fujimura
- Department of Pharmacology, Hyogo College of Medicine, Nishinomiya, Hyogo, Japan
| | - Yuji Ikezawa
- Department of Pharmacology, Hyogo College of Medicine, Nishinomiya, Hyogo, Japan
| | - Yuki Higashi
- Department of Pharmacology, Hyogo College of Medicine, Nishinomiya, Hyogo, Japan
| | - Shinya H Kimura
- Department of Pharmacology, Hyogo College of Medicine, Nishinomiya, Hyogo, Japan
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6
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Phospholipase Cγ2 regulates endocannabinoid and eicosanoid networks in innate immune cells. Proc Natl Acad Sci U S A 2021; 118:2112971118. [PMID: 34607960 DOI: 10.1073/pnas.2112971118] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/24/2021] [Indexed: 02/07/2023] Open
Abstract
Human genetic studies have pointed to a prominent role for innate immunity and lipid pathways in immunological and neurodegenerative disorders. Our understanding of the composition and function of immunomodulatory lipid networks in innate immune cells, however, remains incomplete. Here, we show that phospholipase Cγ2 (PLCγ2 or PLCG2)-mutations in which are associated with autoinflammatory disorders and Alzheimer's disease-serves as a principal source of diacylglycerol (DAG) pools that are converted into a cascade of bioactive endocannabinoid and eicosanoid lipids by DAG lipase (DAGL) and monoacylglycerol lipase (MGLL) enzymes in innate immune cells. We show that this lipid network is tonically stimulated by disease-relevant human mutations in PLCγ2, as well as Fc receptor activation in primary human and mouse macrophages. Genetic disruption of PLCγ2 in mouse microglia suppressed DAGL/MGLL-mediated endocannabinoid-eicosanoid cross-talk and also caused widespread transcriptional and proteomic changes, including the reorganization of immune-relevant lipid pathways reflected in reductions in DAGLB and elevations in PLA2G4A. Despite these changes, Plcg2 -/- mice showed generally normal proinflammatory cytokine and chemokine responses to lipopolysaccharide treatment, instead displaying a more restricted deficit in microglial activation that included impairments in prostaglandin production and CD68 expression. Our findings enhance the understanding of PLCγ2 function in innate immune cells, delineating a role in cross-talk with endocannabinoid/eicosanoid pathways and modulation of subsets of cellular responses to inflammatory stimuli.
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7
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Wendimu MY, Alqinyah M, Vella S, Dean P, Almutairi F, Davila-Rivera R, Rayatpisheh S, Wohlschlegel J, Moreno S, Hooks SB. RGS10 physically and functionally interacts with STIM2 and requires store-operated calcium entry to regulate pro-inflammatory gene expression in microglia. Cell Signal 2021; 83:109974. [PMID: 33705894 DOI: 10.1016/j.cellsig.2021.109974] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 02/19/2021] [Accepted: 03/04/2021] [Indexed: 01/14/2023]
Abstract
Chronic activation of microglia is a driving factor in the progression of neuroinflammatory diseases, and mechanisms that regulate microglial inflammatory signaling are potential targets for novel therapeutics. Regulator of G protein Signaling 10 is the most abundant RGS protein in microglia, where it suppresses inflammatory gene expression and reduces microglia-mediated neurotoxicity. In particular, microglial RGS10 downregulates the expression of pro-inflammatory mediators including cyclooxygenase 2 (COX-2) following stimulation with lipopolysaccharide (LPS). However, the mechanism by which RGS10 affects inflammatory signaling is unknown and is independent of its canonical G protein targeted mechanism. Here, we sought to identify non-canonical RGS10 interacting partners that mediate its anti-inflammatory mechanism. Through RGS10 co-immunoprecipitation coupled with mass spectrometry, we identified STIM2, an endoplasmic reticulum (ER) localized calcium sensor and a component of the store-operated calcium entry (SOCE) machinery, as a novel RGS10 interacting protein in microglia. Direct immunoprecipitation experiments confirmed RGS10-STIM2 interaction in multiple microglia and macrophage cell lines, as well as in primary cells, with no interaction observed with the homologue STIM1. We further determined that STIM2, Orai channels, and the calcium-dependent phosphatase calcineurin are essential for LPS-induced COX-2 production in microglia, and this pathway is required for the inhibitory effect of RGS10 on COX-2. Additionally, our data demonstrated that RGS10 suppresses SOCE triggered by ER calcium depletion and that ER calcium depletion, which induces SOCE, amplifies pro-inflammatory genes. In addition to COX-2, we also show that RGS10 suppresses the expression of pro-inflammatory cytokines in microglia in response to thrombin and LPS stimulation, and all of these effects require SOCE. Collectively, the physical and functional links between RGS10 and STIM2 suggest a complex regulatory network connecting RGS10, SOCE, and pro-inflammatory gene expression in microglia, with broad implications in the pathogenesis and treatment of chronic neuroinflammation.
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Affiliation(s)
- Menbere Y Wendimu
- From the Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, GA 30602, United States of America
| | - Mohammed Alqinyah
- From the Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, GA 30602, United States of America
| | - Stephen Vella
- Department of Cellular Biology, University of Georgia, Athens, GA 30602, United States of America
| | - Phillip Dean
- From the Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, GA 30602, United States of America
| | - Faris Almutairi
- From the Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, GA 30602, United States of America
| | - Roseanne Davila-Rivera
- From the Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, GA 30602, United States of America
| | - Shima Rayatpisheh
- Department of Biological Chemistry, University of California, Los Angeles 90095, United States of America
| | - James Wohlschlegel
- Department of Biological Chemistry, University of California, Los Angeles 90095, United States of America
| | - Silvia Moreno
- Department of Cellular Biology, University of Georgia, Athens, GA 30602, United States of America
| | - Shelley B Hooks
- From the Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, GA 30602, United States of America.
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8
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Huang CT, Lue JH, Cheng TH, Tsai YJ. Glycemic control with insulin attenuates sepsis-associated encephalopathy by inhibiting glial activation via the suppression of the nuclear factor kappa B and mitogen-activated protein kinase signaling pathways in septic rats. Brain Res 2020; 1738:146822. [PMID: 32272096 DOI: 10.1016/j.brainres.2020.146822] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 04/03/2020] [Accepted: 04/04/2020] [Indexed: 12/11/2022]
Abstract
Sepsis-associated encephalopathy (SAE) is frequently encountered in critically ill patients. Hyperglycemia is a common phenomenon among patients with sepsis, and glycemic control improves patient outcomes. Therefore, here, we aimed to explore whether glycemic control using insulin inhibits the pro-inflammatory cytokine response and glial activation in the cerebrum and is concomitantly associated with the relief of SAE. Using cecal ligation and puncture (CLP), sepsis was induced in male Sprague-Dawley rats. The CLP rats were administered intravenous glucose or subjected to subcutaneous insulin implant within the first hour after CLP. The survival rate, blood glucose (BG) values, and behavioral expression were assessed daily for 5 days after CLP. At day 5 after CLP, electroencephalography (EEG) recordings and blood-brain barrier (BBB) permeability testing were performed. Immunohistochemistry, immunoblotting, and enzyme-linked immunosorbent assays were used to evaluate glial activation and the pro-inflammatory cytokine response qualitatively and quantitatively, respectively. The glucose-treated CLP rats (BG > 390 mg/dL) exhibited a decline in survival rate; insensitivity to mechanical and thermal stimuli; slowed EEG activity; and an increase in BBB permeability, pro-inflammatory cytokine (TNF-α, IL-1β, and IL-6) levels, and glial activation (astrocytes and microglia) in the cerebral tissues compared with CLP rats (BG ~ 270 mg/dL). Double-immunofluorescence showed that activated astrocytes and microglia co-expressed phosphorylated nuclear factor kappa B and mitogen-activated protein kinases, respectively. Furthermore, glycemic control using insulin therapy maintained the BG at 120-160 mg/dL and inhibited the production of pro-inflammatory cytokines and glial activation in the cerebrum of septic rats. In addition, the survival rate, sensory threshold, EEG activity, and BBB permeability recovered to near-normal levels in septic rats after insulin therapy. Taken together, the results of this study elucidated the pathophysiological alterations in brains subjected to sepsis, especially regarding glycemic control. These findings improve our understanding of SAE and support the importance of glycemic control in sepsis.
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Affiliation(s)
- Chun-Ta Huang
- Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan; Graduate Institute of Clinical Medicine, National Taiwan University, Taipei, Taiwan
| | - June-Horng Lue
- Department of Anatomy and Cell Biology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Tong-Hong Cheng
- Department of Internal Medicine, Taoyuan Armed Forces General Hospital, Taoyuan, Taiwan
| | - Yi-Ju Tsai
- Graduate Institute of Biomedical and Pharmaceutical Science, College of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan.
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9
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Sankar SB, Pybus AF, Liew A, Sanders B, Shah KJ, Wood LB, Buckley EM. Low cerebral blood flow is a non-invasive biomarker of neuroinflammation after repetitive mild traumatic brain injury. Neurobiol Dis 2018; 124:544-554. [PMID: 30592976 DOI: 10.1016/j.nbd.2018.12.018] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 12/04/2018] [Accepted: 12/24/2018] [Indexed: 01/19/2023] Open
Abstract
Previous work has shown that non-invasive optical measurement of low cerebral blood flow (CBF) is an acute biomarker of poor long-term cognitive outcome after repetitive mild traumatic brain injury (rmTBI). Herein, we explore the relationship between acute cerebral blood flow and underlying neuroinflammation. Specifically, because neuroinflammation is a driver of secondary injury after TBI, we hypothesized that both glial activation and inflammatory signaling are associated with acute CBF and, by extension, with long-term cognitive outcome after rmTBI. To test this hypothesis, cortical CBF was non-invasively measured in anesthetized mice 4 h after 3 repetitive closed head injuries spaced once-daily, at which time brains were collected. Right hemispheres were fixed for immunohistochemical staining for glial activation markers Iba1 and GFAP while left hemispheres were used to quantify Iba1 and GFAP expression via Western blot as well as 32 cytokines and 21 phospho-proteins in the MAPK, PI3K/Akt, and NF-κB pathways using a Luminex multiplexed immunoassay. N = 8/7 injured/sham C57/black-6 adult male mice were studied. Within the injured group, CBF inversely correlated with Iba1 expression (R = -0.86, p < .01). Further, partial least squares regression analysis revealed significant correlations between CBF and expression of multiple pro-inflammatory cytokines, including RANTES and IL-17. Finally, within the injured group, phosphorylation of specific signals in the MAPK and NF-κB intracellular signaling pathways (e.g., p38 MAPK and NF-κB) were significantly positively correlated with Iba1. In total, our data indicate that acute cerebral blood flow after rmTBI is a biomarker of underlying neuroinflammatory pathology.
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Affiliation(s)
- Sitara B Sankar
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, USA; Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, USA
| | - Alyssa F Pybus
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, USA; Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, USA
| | - Amanda Liew
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, USA
| | - Bharat Sanders
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, USA
| | - Kajol J Shah
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, USA
| | - Levi B Wood
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, USA; Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, USA; George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, USA.
| | - Erin M Buckley
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, USA; Department of Pediatrics, School of Medicine, Emory University, USA.
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10
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Ikeda-Matsuo Y, Miyata H, Mizoguchi T, Ohama E, Naito Y, Uematsu S, Akira S, Sasaki Y, Tanabe M. Microsomal prostaglandin E synthase-1 is a critical factor in dopaminergic neurodegeneration in Parkinson's disease. Neurobiol Dis 2018; 124:81-92. [PMID: 30423474 DOI: 10.1016/j.nbd.2018.11.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 11/01/2018] [Accepted: 11/09/2018] [Indexed: 11/17/2022] Open
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder of uncertain pathogenesis characterized by the loss of nigrostriatal dopaminergic neurons. Although increased production of prostaglandin E2 (PGE2) has been implicated in tissue damage in several pathological settings, the role of microsomal prostaglandin E synthase-1 (mPGES-1), an inducible terminal enzyme for PGE2 synthesis, in dopaminergic neurodegeneration remains unclear. Here we show that mPGES-1 is up-regulated in the dopaminergic neurons of the substantia nigra of postmortem brain tissue from PD patients and in neurotoxin 6-hydroxydopamine (6-OHDA)-induced PD mice. The expression of mPGES-1 was also up-regulated in cultured dopaminergic neurons stimulated with 6-OHDA. The genetic deletion of mPGES-1 not only abolished 6-OHDA-induced PGE2 production but also inhibited 6-OHDA-induced dopaminergic neurodegeneration both in vitro and in vivo. Nigrostriatal projections, striatal dopamine content, and neurological functions were significantly impaired by 6-OHDA administration in wild-type (WT) mice, but not in mPGES-1 knockout (KO) mice. Furthermore, in cultured primary mesencephalic neurons, addition of PGE2 to compensate for the deficiency of 6-OHDA-induced PGE2 production in mPGES-1 KO neurons recovered 6-OHDA toxicity to almost the same extent as that seen in WT neurons. These results suggest that induction of mPGES-1 enhances 6-OHDA-induced dopaminergic neuronal death through excessive PGE2 production. Thus, mPGES-1 may be a valuable therapeutic target for treatment of PD.
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Affiliation(s)
- Yuri Ikeda-Matsuo
- Laboratory of Pharmacology, Department of Clinical Pharmacy, Faculty of Pharmaceutical Sciences, Hokuriku University, Japan; Laboratory of Pharmacology, School of Pharmaceutical Sciences, Kitasato University, Japan.
| | - Hajime Miyata
- Department of Neuropathology, Research Institute for Brain and Blood Vessels - AKITA, Japan
| | - Tomoko Mizoguchi
- Laboratory of Pharmacology, School of Pharmaceutical Sciences, Kitasato University, Japan
| | | | - Yasuhito Naito
- Laboratory of Pharmacology, School of Pharmaceutical Sciences, Kitasato University, Japan
| | - Satoshi Uematsu
- Department of Mucosal Immunology, School of Medicine, Chiba University, Japan; Division of Innate Immune Regulation, International Research and Development Center for Mucosal Vaccines, The Institute of Medical Science, The University of Tokyo, Japan
| | - Shizuo Akira
- Laboratory of Host Defense, WPI Immunology Frontier Research Center, Osaka University, Japan
| | - Yasuharu Sasaki
- Laboratory of Pharmacology, School of Pharmaceutical Sciences, Kitasato University, Japan
| | - Mitsuo Tanabe
- Laboratory of Pharmacology, School of Pharmaceutical Sciences, Kitasato University, Japan
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11
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Isami K, Imai S, Sukeishi A, Nagayasu K, Shirakawa H, Nakagawa T, Kaneko S. The impact of mouse strain-specific spatial and temporal immune responses on the progression of neuropathic pain. Brain Behav Immun 2018; 74:121-132. [PMID: 30171890 DOI: 10.1016/j.bbi.2018.08.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 08/09/2018] [Accepted: 08/28/2018] [Indexed: 12/16/2022] Open
Abstract
The present study was designed to investigate the correlation between the spatial and temporal aspects of immune responses and genetic heterogeneity in the progression of peripheral neuropathic pain. To address this issue, we first screened four inbred mouse strains (C57BL/6J, C3H/He, DBA/2, and A/J mice) to identify high- and low-responder strains to mechanical hypersensitivity induced by partial sciatic nerve ligation (pSNL). Among these strains, the C57BL/6J strain showed the highest vulnerability to pSNL-induced mechanical hypersensitivity, whereas the C3H/HeSlc strain was most resistant. C3H/HeSlc mice exhibited a significant increase in CD206-immunoreactivity (anti-inflammatory macrophages) in the dorsal root ganglia (DRG) at 3 and 7 days, and lower Iba1-immunoreactivity (microglia) in the spinal cord from 3 to 14 days after pSNL than C57BL/6J mice. These phenomena might be associated with a decrease in the production of inflammatory factors (interleukin-1β, interleukin-6, and CX3CL1) in the DRG and the poor responsiveness of spinal microglia (i.e. microglial production of IL1β, CCL2, and TNFα) against CX3CL1 in C3H/HeSlc mice. Behavioral experiments using bone marrow (BM) chimeric mice derived by crossing C3H/HeSlc and C57BL/6J strains showed that the strength of mechanical hypersensitivity 3 days following pSNL was inversely correlated with the increase in the ratio of anti-inflammatory/pro-inflammatory DRG macrophages, which was based on the BM-derived hematopoietic cells from donor mice. By contrast, the intensity of Iba1-immunoreactivity (microglia) in the spinal cord was dependent on the phenotypes of recipient mice, but not affected by the phenotypes of BM-derived donor hematopoietic cells. These findings suggest that the strain-specific aspects of DRG macrophages and spinal microglia might be related to the early and late phases of pSNL-induced mechanical hypersensitivity, respectively. This study presents a greater understanding of the differences in neuropathic pain among genetically heterogeneous inbred mouse strains, and provides further insights into the spatial and temporal roles of the immune system in the pathogenesis of neuropathic pain.
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Affiliation(s)
- Koichi Isami
- Department of Molecular Pharmacology, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Satoshi Imai
- Department of Clinical Pharmacology and Therapeutics, Kyoto University Hospital, 54 Shogoin-Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan.
| | - Asami Sukeishi
- Department of Molecular Pharmacology, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Kazuki Nagayasu
- Department of Molecular Pharmacology, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Hisashi Shirakawa
- Department of Molecular Pharmacology, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Takayuki Nakagawa
- Department of Clinical Pharmacology and Therapeutics, Kyoto University Hospital, 54 Shogoin-Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan.
| | - Shuji Kaneko
- Department of Molecular Pharmacology, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
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12
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Abstract
Prostaglandin E2 (PGE2) has been thought to be an important mediator of inflammation in peripheral tissues, but recent studies clearly show the involvement of PGE2 in inflammatory brain diseases. In some animal models of brain disease, the genetic disruption and chemical inhibition of cyclooxygenase (COX)-2 resulted in the reduction of PGE2 and amelioration of symptoms, and it had been thought that PGE2 produced by COX-2 may be involved in the progression of injuries. However, COX-2 produces not only PGE2, but also some other prostanoids, and thus the protective effects of COX-2 inhibition, as well as severe side effects, may be caused by the inhibition of prostanoids other than PGE2. Therefore, to elucidate the role of PGE2, studies of microsomal prostaglandin E synthase-1 (mPGES-1), an inducible terminal enzyme for PGE2 synthesis, have recently been an active area of research. Studies from mPGES-1 deficient mice provide compelling evidence for its role in a variety of inflammatory brain diseases, such as ischemic stroke, Alzheimer's disease and epilepsy, and clues for developing new therapeutic treatments for brain diseases by targeting mPGES-1. Considering that COX inhibitors may non-selectively suppress the production of many types of prostanoids that are essential for normal physiological functioning of the brain and peripheral tissues, as well as induce gastro-intestinal, renal and cardiovascular complications, mPGES-1 inhibitors are expected to be injury-selective and have fewer side-effects when treating human brain diseases. Thus, this paper focuses on recent studies that have demonstrated the involvement of mPGES-1 in pathological brain diseases.
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Affiliation(s)
- Yuri Ikeda-Matsuo
- Laboratory of Pharmacology, Department of Clinical Pharmacy, Faculty of Pharmaceutical Sciences, Hokuriku University
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13
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Lipopolysaccharide (LPS)-mediated priming of toll-like receptor 4 enhances oxidant-induced prostaglandin E 2 biosynthesis in primary murine macrophages. Int Immunopharmacol 2017; 54:226-237. [PMID: 29161659 DOI: 10.1016/j.intimp.2017.11.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 11/13/2017] [Accepted: 11/14/2017] [Indexed: 12/17/2022]
Abstract
Agonists and pseudo-agonists for toll-like receptor 4 (TLR4) are common in our environment. Thus, human exposure to these agents may result in "priming or sensitization" of TLR4. A body of evidence suggests that LPS-mediated sensitization of TLR4 can increase the magnitude of responses to exogenous agents in multiple tissues. We have previously shown that reactive oxygen and nitrogen species (RONS) stimulate TLR4. There is no evidence that LPS-primed TLR4 can influence the magnitude of responses to oxidants from either endogenous or exogenous sources. In the present study, we directly tested the hypothesis that LPS-primed TLR4 will sensitize primary murine peritoneal macrophages (pM) to oxidant-mediated prostaglandin E2 (PGE2) production. We used potassium peroxychromate (PPC) and potassium peroxynitrite (PPN) as direct in vitro sources of exogenous RONS. Our results showed that a direct treatment with PPC or PPN alone as sources of exogenous oxidants had a limited effect on PGE2 biosynthesis. In contrast, pM sensitized by prior incubation with LPS-EK, a TLR4-specific agonist, followed by oxidant stimulation exhibited increased transcriptional and translational expression of cyclooxygenase-2 (COX-2) with enhanced PGE2 biosynthesis/production only in pM derived from TLR4-WT mice but not in TLR4-KO mice. Thus, we have shown a critical role for LPS-primed TLR4 in oxidant-induced inflammatory phenotypes that have the potential to initiate, propagate and maintain many human diseases.
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14
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Cantaut-Belarif Y, Antri M, Pizzarelli R, Colasse S, Vaccari I, Soares S, Renner M, Dallel R, Triller A, Bessis A. Microglia control the glycinergic but not the GABAergic synapses via prostaglandin E2 in the spinal cord. J Cell Biol 2017; 216:2979-2989. [PMID: 28716844 PMCID: PMC5584146 DOI: 10.1083/jcb.201607048] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 02/10/2017] [Accepted: 06/07/2017] [Indexed: 01/08/2023] Open
Abstract
Microglia can influence the excitatory responses of neurons, but less is known about how these immune cells in the brain may influence inhibitory neurotransmitters. Cantaut-Belarif et al. report that prostaglandin production by Toll-like receptor–stimulated microglia can influence the glycinergic but not GABAergic responses of neurons by altering the lateral diffusion of glycine receptors specifically within the synaptic membrane. Microglia control excitatory synapses, but their role in inhibitory neurotransmission has been less well characterized. Herein, we show that microglia control the strength of glycinergic but not GABAergic synapses via modulation of the diffusion dynamics and synaptic trapping of glycine (GlyR) but not GABAA receptors. We further demonstrate that microglia regulate the activity-dependent plasticity of glycinergic synapses by tuning the GlyR diffusion trap. This microglia–synapse cross talk requires production of prostaglandin E2 by microglia, leading to the activation of neuronal EP2 receptors and cyclic adenosine monophosphate–dependent protein kinase. Thus, we now provide a link between microglial activation and synaptic dysfunctions, which are common early features of many brain diseases.
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Affiliation(s)
- Yasmine Cantaut-Belarif
- École Normale Supérieure, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche Scientifique, Paris Sciences et Lettres Research University, Paris, France
| | - Myriam Antri
- Faculté de Chirurgie Dentaire, Neuro-Dol, Centre Hospitalier Universitaire de Clermont-Ferrand, Université Clermont Auvergne, Institut National de la Santé et de la Recherche Médicale, Clermont-Ferrand, France
| | - Rocco Pizzarelli
- École Normale Supérieure, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche Scientifique, Paris Sciences et Lettres Research University, Paris, France
| | - Sabrina Colasse
- École Normale Supérieure, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche Scientifique, Paris Sciences et Lettres Research University, Paris, France
| | - Ilaria Vaccari
- École Normale Supérieure, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche Scientifique, Paris Sciences et Lettres Research University, Paris, France
| | - Sylvia Soares
- Sorbonne Universités, UPMC, CNRS 8246, INSERM 1130, Institut de Biologie Paris-Seine, Neuroscience Paris Seine, Paris, France
| | - Marianne Renner
- École Normale Supérieure, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche Scientifique, Paris Sciences et Lettres Research University, Paris, France
| | - Radhouane Dallel
- Faculté de Chirurgie Dentaire, Neuro-Dol, Centre Hospitalier Universitaire de Clermont-Ferrand, Université Clermont Auvergne, Institut National de la Santé et de la Recherche Médicale, Clermont-Ferrand, France
| | - Antoine Triller
- École Normale Supérieure, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche Scientifique, Paris Sciences et Lettres Research University, Paris, France
| | - Alain Bessis
- École Normale Supérieure, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche Scientifique, Paris Sciences et Lettres Research University, Paris, France
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15
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Viader A, Blankman JL, Zhong P, Liu X, Schlosburg JE, Joslyn CM, Liu QS, Tomarchio AJ, Lichtman AH, Selley DE, Sim-Selley LJ, Cravatt BF. Metabolic Interplay between Astrocytes and Neurons Regulates Endocannabinoid Action. Cell Rep 2015; 12:798-808. [PMID: 26212325 PMCID: PMC4526356 DOI: 10.1016/j.celrep.2015.06.075] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 06/01/2015] [Accepted: 06/25/2015] [Indexed: 12/27/2022] Open
Abstract
The endocannabinoid 2-arachidonoylglycerol (2-AG) is a retrograde lipid messenger that modulates synaptic function, neurophysiology, and behavior. 2-AG signaling is terminated by enzymatic hydrolysis-a reaction that is principally performed by monoacylglycerol lipase (MAGL). MAGL is broadly expressed throughout the nervous system, and the contributions of different brain cell types to the regulation of 2-AG activity in vivo remain poorly understood. Here, we genetically dissect the cellular anatomy of MAGL-mediated 2-AG metabolism in the brain and show that neurons and astrocytes coordinately regulate 2-AG content and endocannabinoid-dependent forms of synaptic plasticity and behavior. We also find that astrocytic MAGL is mainly responsible for converting 2-AG to neuroinflammatory prostaglandins via a mechanism that may involve transcellular shuttling of lipid substrates. Astrocytic-neuronal interplay thus provides distributed oversight of 2-AG metabolism and function and, through doing so, protects the nervous system from excessive CB1 receptor activation and promotes endocannabinoid crosstalk with other lipid transmitter systems.
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Affiliation(s)
- Andreu Viader
- The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, USA; Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | | | - Peng Zhong
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Xiaojie Liu
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Joel E Schlosburg
- Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Christopher M Joslyn
- The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, USA; Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Qing-Song Liu
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Aaron J Tomarchio
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Aron H Lichtman
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Dana E Selley
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Laura J Sim-Selley
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Benjamin F Cravatt
- The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, USA; Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA 92037, USA.
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16
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Zhao H, Luo F, Li H, Zhang L, Yi Y, Wan J. Antinociceptive effect of tetrandrine on LPS-induced hyperalgesia via the inhibition of IKKβ phosphorylation and the COX-2/PGE₂ pathway in mice. PLoS One 2014; 9:e94586. [PMID: 24722146 PMCID: PMC3983227 DOI: 10.1371/journal.pone.0094586] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 03/17/2014] [Indexed: 11/19/2022] Open
Abstract
Tetrandrine (TET) is a bisbenzylisoquinoline alkaloid that is isolated from the Stephania Tetrandra. It is known to possess anti-inflammatory and immunomodulatory effects. We have shown that TET can effectively suppress the production of bacterial lipopolysaccharide (LPS)-induced inflammatory mediators, including cyclooxygenases (COXs), in macrophages. However, whether TET has an antinociceptive effect on LPS-induced hyperalgesia is unknown. In the present study, we investigated the potential antinociceptive effects of TET and the mechanisms by which it elicits its effects on LPS-induced hyperalgesia. LPS effectively evoked hyperalgesia and induced the production of PGE2 in the sera, brain tissues, and cultured astroglia. TET pretreatment attenuated all of these effects. LPS also activated inhibitor of κB (IκB) kinase β (IKKβ) and its downstream components in the IκB/nuclear factor (NF)-κB signaling pathway, including COX-2; the increase in expression levels of these components was significantly abolished by TET. Furthermore, in primary astroglia, knockdown of IKKβ, but not IKKα, reversed the effects of TET on the LPS-induced increase in IκB phosphorylation, P65 phosphorylation, and COX-2. Our results suggest that TET can effectively exert antinociceptive effects on LPS-induced hyperalgesia in mice by inhibiting IKKβ phosphorylation, which leads to the reduction in the production of important pain mediators, such as PGE2 and COX-2, via the IKKβ/IκB/NF-κB pathway.
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Affiliation(s)
- Hengguang Zhao
- Department of Dermatology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Fuling Luo
- Department of Pharmacy, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Hongzhong Li
- Molecular oncology and epigenetics laboratory, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Li Zhang
- Department of Pathophysiology, Chongqing Medical University, Chongqing, China
| | - Yongfen Yi
- Department of Pathology, Molecular Medicine and Tumor Center, Chongqing Medical University, Chongqing, China
- * E-mail: (YFY); (JYW)
| | - Jingyuan Wan
- Chongqing Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing Medical University, Chongqing, China
- * E-mail: (YFY); (JYW)
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17
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Takahashi R, Amano H, Satoh T, Tabata K, Ikeda M, Kitasato H, Akira S, Iwamura M, Majima M. Roles of microsomal prostaglandin E synthase-1 in lung metastasis formation in prostate cancer RM9 cells. Biomed Pharmacother 2014; 68:71-7. [DOI: 10.1016/j.biopha.2013.10.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Accepted: 10/24/2013] [Indexed: 12/20/2022] Open
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Abstract
Sepsis associated encephalopathy (SAE) is a common but poorly understood neurological complication of sepsis. It is characterized by diffuse brain dysfunction secondary to infection elsewhere in the body without overt CNS infection. The pathophysiology of SAE is complex and multifactorial including a number of intertwined mechanisms such as vascular damage, endothelial activation, breakdown of the blood brain barrier, altered brain signaling, brain inflammation, and apoptosis. Clinical presentation of SAE may range from mild symptoms such as malaise and concentration deficits to deep coma. The evaluation of cognitive dysfunction is made difficult by the absence of any specific investigations or biomarkers and the common use of sedation in critically ill patients. SAE thus remains diagnosis of exclusion which can only be made after ruling out other causes of altered mentation in a febrile, critically ill patient by appropriate investigations. In spite of high mortality rate, management of SAE is limited to treatment of the underlying infection and symptomatic treatment for delirium and seizures. It is important to be aware of this condition because SAE may present in early stages of sepsis, even before the diagnostic criteria for sepsis can be met. This review discusses the diagnostic approach to patients with SAE along with its epidemiology, pathophysiology, clinical presentation, and differential diagnosis.
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19
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Kothari P, Pestana R, Mesraoua R, Elchaki R, Khan KMF, Dannenberg AJ, Falcone DJ. IL-6-mediated induction of matrix metalloproteinase-9 is modulated by JAK-dependent IL-10 expression in macrophages. THE JOURNAL OF IMMUNOLOGY 2013; 192:349-57. [PMID: 24285838 DOI: 10.4049/jimmunol.1301906] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The mechanisms by which IL-6 contributes to the pathogenesis of chronic inflammatory diseases and cancer are not fully understood. We previously reported that cyclooxygenase-2 (Cox-2)-dependent PGE2 synthesis regulates macrophage matrix metalloproteinase (MMP)-9 expression, an endopeptidase that participates in diverse pathologic processes. In these studies, we determined whether IL-6 regulates the Cox-2→PGE2→MMP-9 pathway in murine macrophages. IL-6 coinduced Cox-2 and microsomal PGE synthase-1, and inhibited the expression of 15-hydroxyprostaglandin dehydrogenase, leading to increased levels of PGE2. In addition, IL-6 induced MMP-9 expression, suggesting that the observed proteinase expression was regulated by the synthesis of PGE2. However, inhibition of PGE2 synthesis partially suppressed IL-6-mediated induction of MMP-9. In the canonical model of IL-6-induced signaling, JAK activation triggers STAT and MAPK(erk1/2)-signaling pathways. Therefore, the ability of structurally diverse JAK inhibitors to block IL-6-induced MMP-9 expression was examined. Inhibition of JAK blocked IL-6-induced phosphorylation of STAT3, but failed to block the phosphorylation of MAPK(erk1/2), and unexpectedly enhanced MMP-9 expression. In contrast, MEK-1 inhibition blocked IL-6-induced phosphorylation of MAPK(erk1/2) and MMP-9 expression without affecting the phosphorylation of STAT3. Thus, IL-6-induced MMP-9 expression is dependent on the activation of MAPK(erk1/2) and is restrained by a JAK-dependent gene product. Using pharmacologic and genetic approaches, we identified JAK-dependent induction of IL-10 as a potent feedback mechanism controlling IL-6-induced MMP-9 expression. Together, these data reveal that IL-6 induces MMP-9 expression in macrophages via Cox-2-dependent and -independent mechanisms, and identifies a potential mechanism linking IL-6 to the pathogenesis of chronic inflammatory diseases and cancer.
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Affiliation(s)
- Poonam Kothari
- Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, NY 10065
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20
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Affiliation(s)
- Yuri Ikeda-Matsuo
- Laboratory of Pharmacology, School of Pharmaceutical Sciences, Kitasato University
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21
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Straccia M, Dentesano G, Valente T, Pulido-Salgado M, Solà C, Saura J. CCAAT/enhancer binding protein β regulates prostaglandin E synthase expression and prostaglandin E2 production in activated microglial cells. Glia 2013; 61:1607-19. [PMID: 23893854 DOI: 10.1002/glia.22542] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Revised: 04/19/2013] [Accepted: 05/21/2013] [Indexed: 11/11/2022]
Abstract
The eicosanoid prostaglandin E2 (PGE2 ) plays important roles in neuroinflammation and it is produced by the sequential action of the enzymes cyclooxygenase-2 (COX-2) and prostaglandin E synthase (PTGES). The expression of both enzymes and the production of PGE2 are increased in neuroinflammation. The objective of this study was to elucidate whether the transcription factor CCAAT/enhancer binding protein β (C/EBPβ) regulates the expression of prostaglandin synthesis enzymes in neuroinflammation. To this aim, the expression of these enzymes in wild-type and C/EBPβ-null mice was analyzed in vitro and in vivo. In mixed glial cultures, lipopolysaccharide (LPS) ± interferon γ (IFN-γ) induced C/EBPβ binding to COX-2 and PTGES promoters. LPS ± IFN-γ-induced increases in PTGES expression and in PGE2 production in mixed glial and microglial cultures were abrogated in the absence of C/EBPβ. Also, increased brain PTGES expression induced by systemic LPS administration was markedly reduced in C/EBPβ-null mice. In contrast to PTGES, the induction of COX-2 expression in vitro or in vivo was not markedly affected by the absence of C/EBPβ. These results demonstrate that C/EBPβ regulates PTGES expression and PGE2 production by activated microglial cells in vitro and point to C/EBPβ as a regulator of PTGES expression in vivo in the inflamed central nervous system. Altogether, these findings strengthen the proposed role of C/EBPβ as a key player in the orchestration of neuroinflammatory gene response.
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Affiliation(s)
- Marco Straccia
- Biochemistry and Molecular Biology Unit, School of Medicine, University of Barcelona, IDIBAPS, Barcelona, Spain
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22
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Prostaglandin E2 and the suppression of phagocyte innate immune responses in different organs. Mediators Inflamm 2012; 2012:327568. [PMID: 23024463 PMCID: PMC3449139 DOI: 10.1155/2012/327568] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Revised: 04/19/2012] [Accepted: 05/03/2012] [Indexed: 12/15/2022] Open
Abstract
The local and systemic production of prostaglandin E2 (PGE2) and its actions in phagocytes lead to immunosuppressive conditions. PGE2 is produced at high levels during inflammation, and its suppressive effects are caused by the ligation of the E prostanoid receptors EP2 and EP4, which results in the production of cyclic AMP. However, PGE2 also exhibits immunostimulatory properties due to binding to EP3, which results in decreased cAMP levels. The various guanine nucleotide-binding proteins (G proteins) that are coupled to the different EP receptors account for the pleiotropic roles of PGE2 in different disease states. Here, we discuss the production of PGE2 and the actions of this prostanoid in phagocytes from different tissues, the relative contribution of PGE2 to the modulation of innate immune responses, and the novel therapeutic opportunities that can be used to control inflammatory responses.
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23
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Agulhon C, Sun MY, Murphy T, Myers T, Lauderdale K, Fiacco TA. Calcium Signaling and Gliotransmission in Normal vs. Reactive Astrocytes. Front Pharmacol 2012; 3:139. [PMID: 22811669 PMCID: PMC3395812 DOI: 10.3389/fphar.2012.00139] [Citation(s) in RCA: 115] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Accepted: 06/26/2012] [Indexed: 01/07/2023] Open
Abstract
A prominent area of neuroscience research over the past 20 years has been the acute modulation of neuronal synaptic activity by Ca2+-dependent release of the transmitters ATP, D-serine, and glutamate (called gliotransmitters) by astrocytes. Although the physiological relevance of this mechanism is under debate, emerging evidence suggests that there are critical factors in addition to Ca2+ that are required for gliotransmitters to be released from astrocytes. Interestingly, these factors include activated microglia and the proinflammatory cytokine Tumor Necrosis Factor α (TNFα), chemotactic cytokine Stromal cell-Derived Factor-1α (SDF-1α), and inflammatory mediator prostaglandin E2 (PGE2). Of note, microglial activation and release of inflammatory molecules from activated microglia and reactive astrocytes can occur within minutes of a triggering stimulus. Therefore, activation of astrocytes by inflammatory molecules combined with Ca2+ elevations may lead to gliotransmitter release, and be an important step in the early sequence of events contributing to hyperexcitability, excitotoxicity, and neurodegeneration in the damaged or diseased brain. In this review, we will first examine evidence questioning Ca2+-dependent gliotransmitter release from astrocytes in healthy brain tissue, followed by a close examination of recent work suggesting that Ca2+-dependent gliotransmitter release occurs as an early event in the development of neurological disorders and neuroinflammatory and neurodegenerative diseases.
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Affiliation(s)
- Cendra Agulhon
- UFR Biomédicale, CNRS UMR 8154, Université Paris Descartes Paris, France
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Shin JH, Lee YA, Lee JK, Lee YB, Cho W, Im DS, Lee JH, Yun BS, Springer JE, Gwag BJ. Concurrent blockade of free radical and microsomal prostaglandin E synthase-1-mediated PGE2 production improves safety and efficacy in a mouse model of amyotrophic lateral sclerosis. J Neurochem 2012; 122:952-61. [PMID: 22537108 DOI: 10.1111/j.1471-4159.2012.07771.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
While free radicals and inflammation constitute major routes of neuronal injury occurring in amyotrophic lateral sclerosis (ALS), neither antioxidants nor non-steroidal anti-inflammatory drugs have shown significant efficacy in human clinical trials. We examined the possibility that concurrent blockade of free radicals and prostaglandin E(2) (PGE(2))-mediated inflammation might constitute a safe and effective therapeutic approach to ALS. We have developed 2-hydroxy-5-[2-(4-trifluoromethylphenyl)-ethylaminobenzoic acid] (AAD-2004) as a derivative of aspirin. AAD-2004 completely removed free radicals at 50 nM as a potent spin-trapping molecule and inhibited microsomal PGE(2) synthase-1 (mPGES-1) activity in response to both lipopolysaccharide-treated BV2 cell with IC(50) of 230 nM and recombinant human mPGES-1 protein with IC(50) of 249 nM in vitro. In superoxide dismutase 1(G93A) transgenic mouse model of ALS, AAD-2004 blocked free radical production, PGE(2) formation, and microglial activation in the spinal cords. As a consequence, AAD-2004 reduced autophagosome formation, axonopathy, and motor neuron degeneration, improving motor function and increasing life span. In these assays, AAD-2004 was superior to riluzole or ibuprofen. Gastric bleeding was not induced by AAD-2004 even at a dose 400-fold higher than that required to obtain maximal therapeutic efficacy in superoxide dismutase 1(G93A). Targeting both mPGES-1-mediated PGE(2) and free radicals may be a promising approach to reduce neurodegeneration in ALS and possibly other neurodegenerative diseases.
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Affiliation(s)
- Jin Hee Shin
- Department of Neuroscience, Ajou University School of Medicine, Suwon, South Korea GNT Pharma, Yongin, South Korea
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TRPM2 contributes to inflammatory and neuropathic pain through the aggravation of pronociceptive inflammatory responses in mice. J Neurosci 2012; 32:3931-41. [PMID: 22423113 DOI: 10.1523/jneurosci.4703-11.2012] [Citation(s) in RCA: 150] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Accumulating evidence suggests that neuroimmune interactions contribute to pathological pain. Transient receptor potential melastatin 2 (TRPM2) is a nonselective Ca²⁺-permeable cation channel that acts as a sensor for reactive oxygen species. TRPM2 is expressed abundantly in immune cells and is important in inflammatory processes. The results of the present study show that TRPM2 plays a crucial role in inflammatory and neuropathic pain. While wild-type and TRPM2 knock-out mice showed no difference in their basal sensitivity to mechanical and thermal stimulation, nocifensive behaviors in the formalin test were reduced in TRPM2 knock-out mice. In carrageenan-induced inflammatory pain and sciatic nerve injury-induced neuropathic pain models, mechanical allodynia and thermal hyperalgesia were attenuated in TRPM2 knock-out mice. Carrageenan-induced inflammation and sciatic nerve injury increased the expression of TRPM2 mRNA in the inflamed paw and around the injured sciatic nerve, respectively. TRPM2 deficiency diminished the infiltration of neutrophils and the production of chemokine (C-X-C motif) ligand-2 (CXCL2), a major chemokine that recruits neutrophils, but did not alter the recruitment of F4/80-positive macrophages in the inflamed paw or around the injured sciatic nerve. Microglial activation after nerve injury was suppressed in the spinal cord of TRPM2 knock-out mice. Furthermore, CXCL2 production and inducible nitric oxide synthase induction were diminished in cultured macrophages and microglia derived from TRPM2 knock-out mice. Together, these results suggest that TRPM2 expressed in macrophages and microglia aggravates peripheral and spinal pronociceptive inflammatory responses and contributes to the pathogenesis of inflammatory and neuropathic pain.
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Hanada M, Sugiura Y, Shinjo R, Masaki N, Imagama S, Ishiguro N, Matsuyama Y, Setou M. Spatiotemporal alteration of phospholipids and prostaglandins in a rat model of spinal cord injury. Anal Bioanal Chem 2012; 403:1873-84. [PMID: 22415026 DOI: 10.1007/s00216-012-5900-3] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Revised: 01/27/2012] [Accepted: 02/24/2012] [Indexed: 10/28/2022]
Abstract
We determined quantitative and qualitative alterations in lipids during the occurrence and progression of spinal cord injury (SCI) in rats to identify potential clinical indicators of SCI pathology. Imaging mass spectrometry (IMS) was used to visualize twelve molecular species of phosphatidylcholine (PC) on thin slices of spinal cord with SCI. In addition, twelve species of phospholipids and five species of prostaglandins (PGs) were quantified by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) of lipid extracts from control/injured spinal cords. Unique distribution patterns were observed for phospholipids with different fatty acid compositions, and distinct dynamic changes were seen in both their amounts and their distributions in tissue as tissue damage resulting from SCI progressed. In particular, PCs containing docosahexaenoic acid localized to the large nucleus in the anterior horn region at one day post-SCI and rapidly decreased thereafter. In contrast, PCs containing arachidonic acid (AA-PCs) were normally found in the posterior horn region and were intensely and temporarily elevated one week after SCI. Lysophosphatidylcholines (LPCs) also increased at the same SCI stage and in regions with elevated AA-PCs, indicating the release of AA and the production of PGs. Moreover, LC-ESI-MS/MS analysis of lipid extracts from the spinal cord tissue at the impact site demonstrated a peak in PGE2 that reflected the elevation/reduction pattern of AA-PCs and LPC. Although further investigation is required, we suggest that invasive immune cells that penetrated from the impaired blood-brain barrier at 1-2 weeks post-SCI may have produced LPCs, released AA from AA-PCs, and produced PGs in SCI tissue at sites enriched in AA-PCs/LPC.
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Affiliation(s)
- Mitsuru Hanada
- Department of Orthopaedic Surgery, Hamamatsu University School of Medicine, Handayama 1-20-1, Hamamatsu, Shizuoka 431-3192, Japan
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Khan KMF, Kothari P, Du B, Dannenberg AJ, Falcone DJ. Matrix metalloproteinase-dependent microsomal prostaglandin E synthase-1 expression in macrophages: role of TNF-α and the EP4 prostanoid receptor. THE JOURNAL OF IMMUNOLOGY 2012; 188:1970-80. [PMID: 22227567 DOI: 10.4049/jimmunol.1102383] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Matrix metalloproteinase (MMP)-9 contributes to the pathogenesis of chronic inflammatory diseases and cancer. Thus, identifying targetable components of signaling pathways that regulate MMP-9 expression may have broad therapeutic implications. Our previous studies revealed a nexus between metalloproteinases and prostanoids whereby MMP-1 and MMP-3, commonly found in inflammatory and neoplastic foci, stimulate macrophage MMP-9 expression via the release of TNF-α and subsequent induction of cyclooxygenase-2 and PGE(2) engagement of EP4 receptor. In the current study, we determined whether MMP-induced cyclooxygenase-2 expression was coupled to the expression of prostaglandin E synthase family members. We found that MMP-1- and MMP-3-dependent release of TNF-α induced rapid and transient expression of early growth response protein 1 in macrophages followed by sustained elevation in microsomal prostaglandin synthase 1 (mPGES-1) expression. Metalloproteinase-induced PGE(2) levels and MMP-9 expression were markedly attenuated in macrophages in which mPGES-1 was silenced, thereby identifying mPGES-1 as a therapeutic target in the regulation of MMP-9 expression. Finally, the induction of mPGES-1 was regulated, in part, through a positive feedback loop dependent on PGE(2) binding to EP4. Thus, in addition to inhibiting macrophage MMP-9 expression, EP4 antagonists emerge as potential therapy to reduce mPGES-1 expression and PGE(2) levels in inflammatory and neoplastic settings.
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Affiliation(s)
- K M Faisal Khan
- Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, NY 10065, USA
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Font-Nieves M, Sans-Fons MG, Gorina R, Bonfill-Teixidor E, Salas-Pérdomo A, Márquez-Kisinousky L, Santalucia T, Planas AM. Induction of COX-2 enzyme and down-regulation of COX-1 expression by lipopolysaccharide (LPS) control prostaglandin E2 production in astrocytes. J Biol Chem 2012; 287:6454-68. [PMID: 22219191 DOI: 10.1074/jbc.m111.327874] [Citation(s) in RCA: 156] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Pathological conditions and pro-inflammatory stimuli in the brain induce cyclooxygenase-2 (COX-2), a key enzyme in arachidonic acid metabolism mediating the production of prostanoids that, among other actions, have strong vasoactive properties. Although low basal cerebral COX-2 expression has been reported, COX-2 is strongly induced by pro-inflammatory challenges, whereas COX-1 is constitutively expressed. However, the contribution of these enzymes in prostanoid formation varies depending on the stimuli and cell type. Astrocyte feet surround cerebral microvessels and release molecules that can trigger vascular responses. Here, we investigate the regulation of COX-2 induction and its role in prostanoid generation after a pro-inflammatory challenge with the bacterial lipopolysaccharide (LPS) in astroglia. Intracerebral administration of LPS in rodents induced strong COX-2 expression mainly in astroglia and microglia, whereas COX-1 expression was predominant in microglia and did not increase. In cultured astrocytes, LPS strongly induced COX-2 and microsomal prostaglandin-E(2) (PGE(2)) synthase-1, mediated by the MyD88-dependent NFκB pathway and influenced by mitogen-activated protein kinase pathways. Studies in COX-deficient cells and using COX inhibitors demonstrated that COX-2 mediated the high production of PGE(2) and, to a lesser extent, other prostanoids after LPS. In contrast, LPS down-regulated COX-1 in an MyD88-dependent fashion, and COX-1 deficiency increased PGE(2) production after LPS. The results show that astrocytes respond to LPS by a COX-2-dependent production of prostanoids, mainly vasoactive PGE(2), and suggest that the coordinated down-regulation of COX-1 facilitates PGE(2) production after TLR-4 activation. These effects might induce cerebral blood flow responses to brain inflammation.
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Affiliation(s)
- Miriam Font-Nieves
- Department of Brain Ischemia and Neurodegeneration, Institute for Biomedical Research of Barcelona, Consejo Superior de Investigaciones Científicas, Institut d'Investigacions Biomèdiques August Pi i Sunyer, 08036 Barcelona, Spain
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Inhibition of prostaglandin E2 EP3 receptors improves stroke injury via anti-inflammatory and anti-apoptotic mechanisms. J Neuroimmunol 2011; 238:34-43. [DOI: 10.1016/j.jneuroim.2011.06.014] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2009] [Revised: 06/22/2011] [Accepted: 06/24/2011] [Indexed: 01/05/2023]
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Wu T, Wu H, Wang J, Wang J. Expression and cellular localization of cyclooxygenases and prostaglandin E synthases in the hemorrhagic brain. J Neuroinflammation 2011; 8:22. [PMID: 21385433 PMCID: PMC3062590 DOI: 10.1186/1742-2094-8-22] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2010] [Accepted: 03/08/2011] [Indexed: 01/05/2023] Open
Abstract
Background Although cyclooxygenases (COX) and prostaglandin E synthases (PGES) have been implicated in ischemic stroke injury, little is known about their role in intracerebral hemorrhage (ICH)-induced brain damage. This study examines the expression and cellular localization of COX-1, COX-2, microsomal PGES-1 (mPGES-1), mPGES-2, and cytosolic PGES (cPGES) in mice that have undergone hemorrhagic brain injury. Methods ICH was induced in C57BL/6 mice by intrastriatal injection of collagenase. Expression and cellular localization of COX-1, COX-2, mPGES-1, mPGES-2, and cPGES were examined by immunofluorescence staining. Results In the hemorrhagic brain, COX-1, mPGES-2, and cPGES were expressed constitutively in neurons; COX-1 was also constitutively expressed in microglia. The immunoreactivity of COX-2 was increased in neurons and astrocytes surrounding blood vessels at 5 h and then tended to decrease in neurons and increase in astrocytes at 1 day. At 3 days after ICH, COX-2 was observed primarily in astrocytes but was absent in neurons. Interestingly, the immunoreactivity of mPGES-1 was increased in neurons in the ipsilateral cortex and astrocytes in the ipsilateral striatum at 1 day post-ICH; the immunoreactivity of astrocytic mPGES-1 further increased at 3 days. Conclusion Our data suggest that microglial COX-1, neuronal COX-2, and astrocytic COX-2 and mPGES-1 may work sequentially to affect ICH outcomes. These findings have implications for efforts to develop anti-inflammatory strategies that target COX/PGES pathways to reduce ICH-induced secondary brain damage.
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Affiliation(s)
- Tao Wu
- Department of Anesthesiology/Critical Care Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
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31
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Tufekci KU, Genc S, Genc K. The endotoxin-induced neuroinflammation model of Parkinson's disease. PARKINSON'S DISEASE 2011; 2011:487450. [PMID: 21331154 PMCID: PMC3034925 DOI: 10.4061/2011/487450] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/14/2010] [Revised: 11/18/2010] [Accepted: 12/16/2010] [Indexed: 01/22/2023]
Abstract
Parkinson's disease (PD) is a common neurodegenerative disorder characterized by the progressive loss of dopaminergic (DA) neurons in the substantia nigra. Although the exact cause of the dopaminergic neurodegeneration remains elusive, recent postmortem and experimental studies have revealed an essential role for neuroinflammation that is initiated and driven by activated microglial and infiltrated peripheral immune cells and their neurotoxic products (such as proinflammatory cytokines, reactive oxygen species, and nitric oxide) in the pathogenesis of PD. A bacterial endotoxin-based experimental model of PD has been established, representing a purely inflammation-driven animal model for the induction of nigrostriatal dopaminergic neurodegeneration. This model, by itself or together with genetic and toxin-based animal models, provides an important tool to delineate the precise mechanisms of neuroinflammation-mediated dopaminergic neuron loss. Here, we review the characteristics of this model and the contribution of neuroinflammatory processes, induced by the in vivo administration of bacterial endotoxin, to neurodegeneration. Furthermore, we summarize the recent experimental therapeutic strategies targeting endotoxin-induced neuroinflammation to elicit neuroprotection in the nigrostriatal dopaminergic system. The potential of the endotoxin-based PD model in the development of an early-stage specific diagnostic biomarker is also emphasized.
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Affiliation(s)
- Kemal Ugur Tufekci
- Department of Neuroscience, Health Science Institute, Dokuz Eylul University, Inciralti, 35340 Izmir, Turkey
| | - Sermin Genc
- Department of Neuroscience, Health Science Institute, Dokuz Eylul University, Inciralti, 35340 Izmir, Turkey
| | - Kursad Genc
- Department of Neuroscience, Health Science Institute, Dokuz Eylul University, Inciralti, 35340 Izmir, Turkey
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Brenneis C, Coste O, Altenrath K, Angioni C, Schmidt H, Schuh CD, Zhang DD, Henke M, Weigert A, Brüne B, Rubin B, Nusing R, Scholich K, Geisslinger G. Anti-inflammatory role of microsomal prostaglandin E synthase-1 in a model of neuroinflammation. J Biol Chem 2010; 286:2331-42. [PMID: 21075851 DOI: 10.1074/jbc.m110.157362] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
A major immunological response during neuroinflammation is the activation of microglia, which subsequently release proinflammatory mediators such as prostaglandin E(2) (PGE(2)). Besides its proinflammatory properties, cyclooxygenase-2 (COX-2)-derived PGE(2) has been shown to exhibit anti-inflammatory effects on innate immune responses. Here, we investigated the role of microsomal PGE(2) synthase-1 (mPGES-1), which is functionally coupled to COX-2, in immune responses using a model of lipopolysaccharide (LPS)-induced spinal neuroinflammation. Interestingly, we found that activation of E-prostanoid (EP)2 and EP4 receptors, but not EP1, EP3, PGI(2) receptor (IP), thromboxane A(2) receptor (TP), PGD(2) receptor (DP), and PGF(2) receptor (FP), efficiently blocked LPS-induced tumor necrosis factor α (TNFα) synthesis and COX-2 and mPGES-1 induction as well as prostaglandin synthesis in spinal cultures. In vivo, spinal EP2 receptors were up-regulated in microglia in response to intrathecally injected LPS. Accordingly, LPS priming reduced spinal synthesis of TNFα, interleukin 1β (IL-1β), and prostaglandins in response to a second intrathecal LPS injection. Importantly, this reduction was only seen in wild-type but not in mPGES-1-deficient mice. Furthermore, intrathecal application of EP2 and EP4 agonists as well as genetic deletion of EP2 significantly reduced spinal TNFα and IL-1β synthesis in mPGES-1 knock-out mice after LPS priming. These data suggest that initial inflammation prepares the spinal cord for a negative feedback regulation by mPGES-1-derived PGE(2) followed by EP2 activation, which limits the synthesis of inflammatory mediators during chronic inflammation. Thus, our data suggest a role of mPGES-1-derived PGE(2) in resolution of neuroinflammation.
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Affiliation(s)
- Christian Brenneis
- Institute of Clinical Pharmacology, Pharmazentrum Frankfurt, ZAFES, Hospital of the Goethe-University, 60590 Frankfurt, Germany
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Ikeda-Matsuo Y, Tanji H, Ota A, Hirayama Y, Uematsu S, Akira S, Sasaki Y. Microsomal prostaglandin E synthase-1 contributes to ischaemic excitotoxicity through prostaglandin E2 EP3 receptors. Br J Pharmacol 2010; 160:847-59. [PMID: 20590584 DOI: 10.1111/j.1476-5381.2010.00711.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE Although microsomal prostaglandin E synthase (mPGES)-1 is known to contribute to stroke injury, the underlying mechanisms remain poorly understood. This study examines the hypothesis that EP(3) receptors contribute to stroke injury as downstream effectors of mPGES-1 neurotoxicity through Rho kinase activation. EXPERIMENTAL APPROACH We used a glutamate-induced excitotoxicity model in cultured rat and mouse hippocampal slices and a mouse middle cerebral artery occlusion-reperfusion model. Effects of an EP(3) receptor antagonist on neuronal damage in mPGES-1 knockout (KO) mice was compared with that in wild-type (WT) mice. KEY RESULTS In cultures of rat hippocampal slices, the mRNAs of EP(1-4) receptors were constitutively expressed and only the EP(3) receptor antagonist ONO-AE3-240 attenuated and only the EP(3) receptor agonist ONO-AE-248 augmented glutamate-induced excitotoxicity in CA1 neurons. Hippocampal slices from mPGES-1 KO mice showed less excitotoxicity than those from WT mice and the EP(3) receptor antagonist did not attenuate the excitotoxicity. In transient focal ischaemia models, injection (i.p.) of an EP(3) antagonist reduced infarction, oedema and neurological dysfunction in WT mice, but not in mPGES-1 KO mice, which showed less injury than WT mice. EP(3) receptor agonist-induced augmentation of excitotoxicity in vitro was ameliorated by the Rho kinase inhibitor Y-27632 and Pertussis toxin. The Rho kinase inhibitor HA-1077 also ameliorated stroke injury in vivo. CONCLUSION AND IMPLICATIONS Activity of mPGES-1 exacerbated stroke injury through EP(3) receptors and activation of Rho kinase and/or G(i). Thus, mPGES-1 and EP(3) receptors may be valuable therapeutic targets for treatment of human stroke.
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Affiliation(s)
- Y Ikeda-Matsuo
- Laboratory of Pharmacology, School of Pharmaceutical Sciences, Kitasato University, Tokyo, Japan.
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Ae T, Ohno T, Hattori Y, Suzuki T, Hosono K, Minamino T, Sato T, Uematsu S, Akira S, Koizumi W, Majima M. Role of microsomal prostaglandin E synthase-1 in the facilitation of angiogenesis and the healing of gastric ulcers. Am J Physiol Gastrointest Liver Physiol 2010; 299:G1139-46. [PMID: 20813913 DOI: 10.1152/ajpgi.00013.2010] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The importance of prostaglandin E(2) in various pathophysiological events emphasizes the necessity of understanding the role of PGE synthases (PGESs) in vivo. However, there has been no report on the functional relevance of microsomal PGES-1 (mPGES-1) to the physiological healing processes of gastric ulcers, or to angiogenesis, which is indispensable to the healing processes. In this report, we tested whether mPGES-1 plays a role in the healing of gastric ulcers and in the enhancement of angiogenesis using mPGES-1 knockout mice (mPGES-1 KO mice) and their wild-type (WT) counterparts. Gastric ulcers were induced by the serosal application of 100% acetic acid, and the areas of the ulcers were measured thereafter. mPGES-1 together with cyclooxygenase-2 were induced in the granulation tissues compared with normal stomach tissues. The healing of acetic acid-induced ulcers was significantly delayed in mPGES-1 KO mice compared with WT. This was accompanied with reduced angiogenesis in ulcer granulation tissues, as estimated by CD31 mRNA levels determined by real-time PCR and the microvessel density in granulation tissues. The mRNA levels of proangiogenic growth factors, such as transforming growth factor-β, basic fibroblast growth factor, and connective tissue growth factor in ulcer granulation tissues determined were reduced in mPGES-1 KO mice compared with WT. The present results suggest that mPGES-1 enhances the ulcer-healing processes and the angiogenesis indispensable to ulcer healing, and that a selective mPGES-1 inhibitor should be used with care in patients with gastric ulcers.
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Affiliation(s)
- Takako Ae
- Department of Pharmacology, Kitasato University School of Medicine, Kanagawa, Japan
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Matsui T, Svensson CI, Hirata Y, Mizobata K, Hua XY, Yaksh TL. Release of prostaglandin E(2) and nitric oxide from spinal microglia is dependent on activation of p38 mitogen-activated protein kinase. Anesth Analg 2010; 111:554-60. [PMID: 20610553 DOI: 10.1213/ane.0b013e3181e3a2a2] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND The spinal release of prostaglandins (PGs), nitric oxide (NO), and cytokines has been implicated in spinal nociceptive processing. Microglia represent a possible cell of origin for these proexcitatory mediators. Spinal microglia possess Toll-like receptor 4 (TLR4) and neurokinin 1 (NK1) receptors, and both receptors play a significant role in peripheral nerve injury- and inflammation-induced spinal sensitization. Accordingly, we examined the properties of the cascades activated by the respective targets, which led to the release of PGE(2) and an increase in nitrite (NO(2)(-)) (a marker of NO) from cultured rat spinal microglia. METHODS Spinal microglia isolated from Sprague-Dawley neonatal rats were cultured with lipopolysaccharide (LPS) or substance P (SP) alone, with LPS in combination with SP, and with LPS in the presence of each inhibitor of cyclooxygenase (COX), NO synthase 2 (NOS2) or p38 mitogen-activated protein kinase (p38), or minocycline for 24 hours and 48 hours. Concentrations of PGE(2) and NO(2)(-) in culture supernatants were measured using an enzyme immunoassay and a colorimetric assay, respectively. RESULTS Application of LPS (a TLR4 ligand, 0.1 to 10 ng/mL) to cultured microglia produced a dose- and time-dependent increase in PGE(2) and NO(2)(-) production, whereas no effects were observed after incubation with SP (an NK1 agonist, up to 10(-5) M) alone or in combination with LPS. Antagonist studies with SC-560 (COX-1 inhibitor) and SC-236 (COX-2 inhibitor) showed that LPS-induced PGE(2) release was generated from both COX-1 and COX-2. LPS-induced NO release was suppressed by 1400W, an inhibitor of NOS2. Minocycline, an agent blocking microglial activation, and SB203580, an inhibitor of p38, both attenuated the LPS-induced PGE(2) and NO release. The 1400W, at the doses that suppressed NO release, also blocked increased PGE(2) release. CONCLUSIONS Our findings suggest that (a) activation of spinal microglia via TLR4 but not NK1 receptors produces PGE(2) and NO release from these cells; (b) the evoked PGE(2) release is generated by both COX-1 and COX-2, and (c) the COX-PGE(2) pathway is regulated by p38 and NOS2. Taken together with our previous in vivo work, the current findings emphasize that p38 in spinal microglia is a key player in regulating production of pronociceptive molecules, such as PGE(2) and NO.
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Affiliation(s)
- Tomohiro Matsui
- Department of Laboratory Sciences, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan
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Akanuma SI, Hosoya KI, Ito S, Tachikawa M, Terasaki T, Ohtsuki S. Involvement of Multidrug Resistance-Associated Protein 4 in Efflux Transport of Prostaglandin E2 across Mouse Blood-Brain Barrier and Its Inhibition by Intravenous Administration of Cephalosporins. J Pharmacol Exp Ther 2010; 333:912-9. [DOI: 10.1124/jpet.109.165332] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
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Ikeda-Matsuo Y, Hirayama Y, Ota A, Uematsu S, Akira S, Sasaki Y. Microsomal prostaglandin E synthase-1 and cyclooxygenase-2 are both required for ischaemic excitotoxicity. Br J Pharmacol 2010; 159:1174-86. [PMID: 20128796 DOI: 10.1111/j.1476-5381.2009.00595.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND AND PURPOSE Although both microsomal prostaglandin E synthase (mPGES)-1 and cyclooxygenase (COX)-2 are critical factors in stroke injury, but the interactions between these enzymes in the ischaemic brain is still obscure. This study examines the hypothesis that mPGES-1 activity is required for COX-2 to cause neuronal damage in ischaemic injury. EXPERIMENTAL APPROACH We used a glutamate-induced excitotoxicity model in cultures of rat or mouse hippocampal slices and a mouse middle cerebral artery occlusion-reperfusion model in vivo. The effect of a COX-2 inhibitor on neuronal damage in mPGES-1 knockout (KO) mice was compared with that in wild-type (WT) mice. KEY RESULTS In rat hippocampal slices, glutamate-induced excitotoxicity, as well as prostaglandin (PG) E(2) production and PGES activation, was significantly attenuated by either MK-886 or NS-398, inhibitors of mPGES-1 and COX-2 respectively; however, co-application of these inhibitors had neither an additive nor a synergistic effect. The protective effect of NS-398 on the excitotoxicity observed in WT slices was completely abolished in mPGES-1 KO slices, which showed less excitotoxicity than WT slices. In the transient focal ischaemia model, mPGES-1 and COX-2 were co-localized in the infarct region of the cortex. Injection of NS-398 reduced not only ischaemic PGE(2) production, but also ischaemic injuries in WT mice, but not in mPGES-1 KO mice, which showed less dysfunction than WT mice. CONCLUSION AND IMPLICATIONS Microsomal prostaglandin E synthase-1 and COX-2 are co-induced by excess glutamate in ischaemic brain. These enzymes are co-localized and act together to exacerbate stroke injury, by excessive PGE(2) production.
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Ikeda-Matsuo Y. Microsomal prostaglandin E synthase-1 is involved in the brain ischemic injury. Inflamm Regen 2010. [DOI: 10.2492/inflammregen.30.26] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Kim Y, Eom S, Kim K, Lee YS, Choe J, Hahn JH, Lee H, Kim YM, Ha KS, Ro JY, Jeoung D. Transglutaminase II interacts with rac1, regulates production of reactive oxygen species, expression of snail, secretion of Th2 cytokines and mediates in vitro and in vivo allergic inflammation. Mol Immunol 2009; 47:1010-22. [PMID: 20004474 DOI: 10.1016/j.molimm.2009.11.017] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2009] [Accepted: 11/13/2009] [Indexed: 12/22/2022]
Abstract
Transglutaminase II (TGase II) is a protein cross-linking enzyme with diverse biological functions. Here we report the role of TGase II in allergic inflammation. Antigen stimulation induced expression and activity of TGase II by activation of NF-kappaB in rat basophilic leukemia (RBL2H3) cells. This induction of TGase II was dependent on FcepsilonRI and EGFR. Interaction between TGase II and rac1 was induced following antigen stimulation. TGase II was responsible for the increased production of reactive oxygen species, expression of prostaglandin E2 synthase (PGE2 synthase) and was responsible for increased secretion of prostaglandin E2. ChIP assay showed that TGase II, through interaction with NF-kappaB, was responsible for the induction of histone deacetylase-3 (HDAC3) and snail by direct binding to promoter sequences. HDAC3 and snail induced by TGase II, exerted transcriptional repression on E-cadherin. Snail exerted negative effect on expression of MMP-2, and secretion of Th2 cytokines. Inhibition of matrix metalloproteinase-2 (MMP-2) inhibited secretion of Th2 cytokines. In vivo induction of TGase II was observed in Balb/c mouse model of IgE antibody-induced passive cutaneous anaphylaxis. Chemical inhibition of TGase II exerted negative effect on IgE-dependent passive cutaneous anaphylaxis. Chemical inhibition of TGase II by cystamine exerted negative effect on Balb/c mouse model of phorbol myristate acetate (PMA)-induced atopic dermatitis. These results suggest novel role of TGase II in allergic inflammation and TGase II can be developed as target for the development of allergy therapeutics.
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Affiliation(s)
- Youngmi Kim
- School of Biological Sciences, College of Natural Sciences, Kangwon National University, Chunchon, Republic of Korea
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Ellagic acid inhibits lipopolysaccharide-induced expression of enzymes involved in the synthesis of prostaglandin E2 in human monocytes. Br J Nutr 2009; 103:1102-9. [DOI: 10.1017/s0007114509992935] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Ellagic acid, a natural polyphenol found in certain fruits, nuts and vegetables, has in recent years been the subject of intense research within the fields of cancer and inflammation. Pain, fever and swelling, all typical symptoms of inflammation, are ascribed to elevated levels of PGE2. In the present study, we have investigated the effects of ellagic acid on PGE2 release and on prostaglandin-synthesising enzymes in human monocytes. Ellagic acid was found to inhibit Ca ionophore A23187-, phorbol myristate acetate- and opsonised zymosan-induced release of PGE2 from monocytes pre-treated with the inflammatory agent lipopolysaccharide. Ellagic acid suppressed the lipopolysaccharide-induced increase in protein expression of cyclo-oxygenase-2 (COX-2), microsomal PGE synthase-1 (mPGEs-1) and cytosolic phospholipase A2α (cPLA2α), while it had no effect on the constitutively expressed COX-1 protein. Ellagic acid had no apparent inhibitory effect on these enzymes when the activities were determined in cell-free assays. We conclude that the inhibitory effect of ellagic acid on PGE2 release from monocytes is due to a suppressed expression of COX-2, mPGEs-1 and cPLA2α, rather than a direct effect on the activities of these enzymes.
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Briet F, Mazer CD, Tsui AKY, Zhang H, Khang J, Pang V, Baker AJ, Hare GMT. Cerebral cortical gene expression in acutely anemic rats: a microarray analysis. Can J Anaesth 2009; 56:921-34. [PMID: 19847587 DOI: 10.1007/s12630-009-9201-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2009] [Accepted: 09/14/2009] [Indexed: 01/29/2023] Open
Abstract
PURPOSE Hemodilution in perioperative patients has been associated with neurological morbidity and increased mortality by undefined mechanisms. This study assesses whether hemodilutional anemia up-regulated inflammatory cerebral gene expression (microarray) to help define the mechanism. METHODS Hemodilution was performed in anesthetized rats by exchanging 50% of the estimated blood volume (30 mL kg(-1)) with pentastarch. Two groups of control animals were utilized, i.e., a non-anesthetized control (Normal Control) and an anesthetized control group (Anesthesia Control). Blood pressure, hemoglobin concentration, and arterial blood gas analysis were performed before and after hemodilution. Cerebral cortex was harvested from isoflurane-anesthetized rats (n = 6) after 6 and 24 hr of recovery and was used to perform complimentary DNA (cDNA) microarray analyses. Pro-inflammatory chemokine and cytokine protein levels were also measured. RESULTS Microarray analysis demonstrated up-regulation of 72 and 27 genes (6 and 24 hr, respectively) in anemic cerebral cortex. These genes were involved in a number of biological functions, including (1) inflammatory responses; (2) angiogenesis; (3) vascular homeostasis; (4) cellular biology; and (5) apoptosis. Chemokine ribonucleic acid (RNA) expression (CXCL-1, -10, and -11) was highest in anemic brain tissue (P < 0.0125 for each). Protein measurements demonstrated a significant increase in interleukin-6, tumor necrosis factor alpha, and monocyte chemoattractant protein-1 (P < 0.05 for each). CONCLUSION This study utilizes microarray technology to elucidate changes in cerebral cortical gene expression in response to acute hemodilution. These findings demonstrate an increase in pro-inflammatory chemokines (RNA, protein) and cytokines (protein). An improved understanding of the inflammatory response to anemia may help to minimize associated morbidity and mortality.
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Affiliation(s)
- Françoise Briet
- Department of Anaesthesia, Keenan Research Centre in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, University of Toronto, Toronto, ON, Canada
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Iyer JP, Srivastava PK, Dev R, Dastidar SG, Ray A. Prostaglandin E(2) synthase inhibition as a therapeutic target. Expert Opin Ther Targets 2009; 13:849-65. [PMID: 19530988 DOI: 10.1517/14728220903018932] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND Most NSAIDs function by inhibiting biosynthesis of PGE(2) by inhibition of COX-1 and/or COX-2. Since COX-1 has a protective function in the gastro-intestinal tract (GIT), non-selective inhibition of both cycloxy genases leads to moderate to severe gastro-intestinal intolerance. Attempts to identify selective inhibitors of COX-2, led to the identification of celecoxib and rofecoxib. However, long-term use of these drugs has serious adverse effects of sudden myocardial infarction and thrombosis. Drug-mediated imbalance in the levels of prostaglandin I(2) (PGI(2)) and thromboxane A(2) (TXA(2)) with a bias towards TXA(2) may be the primary reason for these events. This resulted in the drugs being withdrawn from the market, leaving a need for an effective and safe anti-inflammatory drug. METHODS Recently, the focus of research has shifted to enzymes downstream of COX in the prosta glandin biosynthetic pathway such as prostaglandin E(2) synthases. Microsomal prostaglandin E(2) synthase-1 (mPGES-1) specifically isomerizes PGH(2) to PGE(2), under inflammatory conditions. In this review, we examine the biology of mPGES-1 and its role in disease. Progress in designing molecules that can selectively inhibit mPGES-1 is reviewed. CONCLUSION mPGES-1 has the potential to be a target for anti-inflammatory therapy, devoid of adverse GIT and cardiac effects and warrants further investigation.
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Affiliation(s)
- Jitesh P Iyer
- Department of Pharmacology, New Drug Discovery Research, Ranbaxy Research Laboratories, Plot No-20, Sector-18, Udyog Vihar, Gurgaon, Haryana, India-122015
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Chaudhry U, Zhuang H, Doré S. Microsomal prostaglandin E synthase-2: cellular distribution and expression in Alzheimer's disease. Exp Neurol 2009; 223:359-65. [PMID: 19664621 DOI: 10.1016/j.expneurol.2009.07.027] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2009] [Revised: 06/23/2009] [Accepted: 07/24/2009] [Indexed: 12/31/2022]
Abstract
Nonsteroidal anti-inflammatory drugs, such as cyclooxygenase (COX)-2 inhibitors, have been unsuccessful in slowing or reversing Alzheimer's disease (AD). Thus, understanding the expression patterns of the downstream effectors for the regulation of prostaglandin synthesis may be important for understanding the pathological processes involved in AD and formulating more effective pharmacotherapeutics for this disease. In this study, we used immunofluorescence, immunohistochemistry, and Western blot analysis to compare patterns of microsomal prostaglandin E synthase (mPGES)-2 expression in the middle frontal gyrus (MFG) of AD patients and age-matched controls. In control human brain sections, mPGES-2 immunoreactivity was observed in neurons, activated microglia, and endothelium, but not in resting microglia, astrocytes, or smooth muscle cells. Microsomal PGES-2 immunoreactivity was particularly elevated in the pyramidal neurons of brains from three of five sporadic and four of five familial AD patients compared with four of five age-matched control brains that showed minimal immunoreactivity. In contrast, Western blot analysis revealed no difference in mPGES-2 levels between end-stage AD brain tissue and control brain tissue. These results suggest that in human cortex, mPGES-2 is constitutive in neurons and endothelium and induced in activated microglia. Furthermore, the high immunoreactivity of mPGES-2 in pyramidal neurons of AD brains indicates that it might have a potential role in the functional replacement of cytosolic PGES or inactive mPGES-1 in later stages of AD.
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Affiliation(s)
- Uzma Chaudhry
- Department of Anesthesiology/Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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O'Banion MK. Prostaglandin E2 synthases in neurologic homeostasis and disease. Prostaglandins Other Lipid Mediat 2009; 91:113-7. [PMID: 19393332 DOI: 10.1016/j.prostaglandins.2009.04.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2009] [Revised: 04/10/2009] [Accepted: 04/10/2009] [Indexed: 01/17/2023]
Abstract
Prostaglandin E(2) synthases (PGES) currently comprise a group of three structurally and biologically distinct molecules. These enzymes are part of an important and complex paracrine signaling system involved in a wide range of biological processes. This review focuses on the normal physiological and pathological roles of these enzymes in the nervous system. Specific topics include the role of PGES(s) in fever and sickness behavior, inflammatory pain, and neural disease. Although the field is in its early stages, ongoing development of selective PGES inhibitors for possible use in people creates a significant need for more fully understanding the biological roles of these important enzymes.
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Affiliation(s)
- M Kerry O'Banion
- Department of Neurobiology & Anatomy, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA.
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Golovko MY, Barceló-Coblijn G, Castagnet PI, Austin S, Combs CK, Murphy EJ. The role of α-synuclein in brain lipid metabolism: a downstream impact on brain inflammatory response. Mol Cell Biochem 2008; 326:55-66. [DOI: 10.1007/s11010-008-0008-y] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2008] [Accepted: 06/26/2008] [Indexed: 11/28/2022]
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Homo-timeric structural model of human microsomal prostaglandin E synthase-1 and characterization of its substrate/inhibitor binding interactions. J Comput Aided Mol Des 2008; 23:13-24. [DOI: 10.1007/s10822-008-9233-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2008] [Accepted: 08/05/2008] [Indexed: 10/21/2022]
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de Oliveira ACP, Candelario-Jalil E, Bhatia HS, Lieb K, Hüll M, Fiebich BL. Regulation of prostaglandin E2 synthase expression in activated primary rat microglia: evidence for uncoupled regulation of mPGES-1 and COX-2. Glia 2008; 56:844-55. [PMID: 18383341 DOI: 10.1002/glia.20658] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Prostaglandin E2 (PGE2) is among the most important mediators involved in neuroinflammatory processes. The final step of its synthesis is regulated by enzymes termed prostaglandin E2 synthases (PGES). Three PGES are known, cytosolic (c)PGES, membrane-associated (m)PGES-1 and mPGES-2. The expression of mPGES-1 is induced by inflammatory stimuli such as lipopolysaccharide (LPS), interleukin (IL)-1beta, and tumor necrosis factor (TNF)-alpha. Although some roles of mPGES-1 have already been suggested, its function in the CNS and the signaling pathways involved in its upregulation are poorly understood. In this study, we examined the regulation of mPGES-1 in primary rat microglia and the signaling pathways involved in its expression. Whereas the expression of cPGES and mPGES-2 was not stimulated by LPS, low doses of LPS (0.1-1 ng/mL) sufficiently stimulated mPGES-1 mRNA expression. A corresponding protein synthesis, however, was obtained only with higher doses (10-100 ng/mL). The LPS-induced increase of mPGES-1 was inhibited by different signaling pathway inhibitors, such as SP600125, LY294002, GF109203X, and SC-514, suggesting the involvement of c-Jun N-terminal kinase (JNK), phosphatidylinositol 3-kinase (PI-3K)/Akt, protein kinase C (PKC) pathways, and the nuclear factor (NF)-kappaB, respectively. In contrast to other reports, LPS-induced mPGES-1 synthesis was not invariably coupled to the synthesis of COX-2, since inhibition of PI-3K with LY294002 decreased mPGES-1 but increased COX-2 levels. This detailed view of the intracellular signaling pathways involved in mPGES-1 expression in activated microglia opens a new avenue in the search for novel potential therapeutic targets to reduce neuroinflammation, and demonstrates that mPGES-1 expression is not strictly coupled to the expression of COX-2.
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Kim B, Lee JH, Yang MS, Jou I, Joe EH. Retinoic acid enhances prostaglandin E2 production through increased expression of cyclooxygenase-2 and microsomal prostaglandin E synthase-1 in rat brain microglia. J Neurosci Res 2008; 86:1353-60. [PMID: 18183617 DOI: 10.1002/jnr.21593] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Retinoic acid (RA) is a well-known antiinflammatory agent. In this study, we show that RA has a dual effect on cyclooxygenase-2 (COX-2) expression in inflammatory activated microglia, the resident brain macrophages. After treatment of microglia with LPS or thrombin, COX-2 expression was induced in two phases, specifically, an initial increase at about 12 hr after stimulation followed by a decrease, and another increase at about 48-72 hr. However, PGE(2) and 15d-PGJ(2) were detected at about 12 hr, and the levels continuously increased thereafter. Interestingly, all-trans retinoic acid (ATRA) suppressed the expression of early-phase COX-2 but augmented late-phase COX-2 and inhibited iNOS in the whole time sequence. ATRA enhanced PGE(2) production but had little effect on 15d-PGJ(2). Moreover, ATRA selectively up-regulated the expression of a PGE(2) synthase, mPGES-1, but had little effect on the PGD(2) synthase, H-PGDS. The results collectively suggest that ATRA modulates microglial responses to inflammatory stimulators, particularly at the late phase, via enhancement of COX-2 expression and PGE(2) production.
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Affiliation(s)
- Beomsue Kim
- Neuroscience Graduate Program, Ajou University School of Medicine, Suwon, Kyunggi-do, Korea
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Deumens R, Joosten EAJ, Waxman SG, Hains BC. Locomotor dysfunction and pain: the scylla and charybdis of fiber sprouting after spinal cord injury. Mol Neurobiol 2008; 37:52-63. [PMID: 18415034 DOI: 10.1007/s12035-008-8016-1] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2007] [Accepted: 03/19/2008] [Indexed: 10/22/2022]
Abstract
Injury to the spinal cord (SCI) can produce a constellation of problems including chronic pain, autonomic dysreflexia, and motor dysfunction. Neuroplasticity in the form of fiber sprouting or the lack thereof is an important phenomenon that can contribute to the deleterious effects of SCI. Aberrant sprouting of primary afferent fibers and synaptogenesis within incorrect dorsal horn laminae leads to the development and maintenance of chronic pain as well as autonomic dysreflexia. At the same time, interruption of connections between supraspinal motor control centers and spinal cord output cells, due to lack of successful regenerative sprouting of injured descending fiber tracts, contributes to motor deficits. Similarities in the molecular control of axonal growth of motor and sensory fibers have made the development of cogent therapies difficult. In this study, we discuss recent findings related to the degradation of inhibitory barriers and promotion of sprouting of motor fibers as a strategy for the restoration of motor function and note that this may induce primary afferent fiber sprouting that can contribute to chronic pain. We highlight the importance of careful attentiveness to off-target molecular- and circuit-level modulation of nociceptive processing while moving forward with the development of therapies that will restore motor function after SCI.
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Affiliation(s)
- Ronald Deumens
- Pain Management and Research Center, Department of Anesthesiology, Maastricht University Hospital, P. Debyelaan 25, P.O. Box 5800, 6200 AZ, Maastricht, The Netherlands
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Liu J, Hong Z, Ding J, Liu J, Zhang J, Chen S. Predominant release of lysosomal enzymes by newborn rat microglia after LPS treatment revealed by proteomic studies. J Proteome Res 2008; 7:2033-49. [PMID: 18380473 DOI: 10.1021/pr7007779] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Growing evidence suggest that microglia may play an important role in the pathogenesis of neurodegenerative disease including Parkinson's disease, Alzheimer's disease, and so forth. The activation of microglia may cause neuronal damage through the release of reactive oxygen species and proinflammatory cytokines. However, the early response of microglial cells remains unclear before cells can secrete the proinflammatory cytokines. Here, a time course analysis showed the earliest expression of inducible nitric oxide synthase and cyclooxygenase-2 at 3 and 24 h following lipopolysaccharide (LPS) treatment. To further define initial response proteins of microglia after LPS treatment, we utilized a novel mass spectrometry-based quantitative proteomic technique termed SILAC (for stable isotope labeling by amino acids in cell culture) to compare the protein profiles of the cell culture-conditioned media of 1 h LPS-treated microglia as compared with controls. The proteomic analysis identified 77 secreted proteins using SignalP; of these, 28 proteins were associated with lysosome of cells and 13 lysosome-related proteins displayed significant changes in the relative abundance after 1 h LPS treatment. Four proteins were further evaluated with Western blot, demonstrating good agreement with quantitative proteomic data. These results suggested that microglia first released some lysosomal enzymes which may be involved in neuronal damage process. Furthermore, ammonium chloride, which inhibits microglia lysosomal enzyme activity, could prevent microglia from causing neuronal injury. Hence, in addition to the numerous novel proteins that are potentially important in microglial activation-mediated neurodegeneration revealed by the search, the study has indicated that the early release of lysosomal enzymes in microglial cells would contribute to LPS-activated inflammatory response.
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Affiliation(s)
- Jun Liu
- Department of Neurology & Institute of Neurology, Ruijin Hospital, Shanghai Jiatong University School of Medicine, Shanghai, China
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