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Roflumilast, a Phosphodiesterase-4 Inhibitor, Ameliorates Sleep Deprivation-Induced Cognitive Dysfunction in C57BL/6J Mice. ACS Chem Neurosci 2022; 13:1938-1947. [PMID: 35736514 DOI: 10.1021/acschemneuro.2c00127] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Sleep deprivation (SD) interferes with long-term memory and cognitive functions by overactivation of phosphodiesterase (PDEs) enzymes. PDE4, a nonredundant regulator of the cyclic nucleotides (cAMP), is densely expressed in the hippocampus and is involved in learning and memory processes. In the present study, we investigated the effects of Roflumilast (ROF), a PDE4B inhibitor, on sleep deprivation-induced cognitive dysfunction in a mouse model. Memory assessment was performed using a novel object recognition task, and the hippocampal cAMP level was estimated by the ELISA method. The alterations in the expressions of PDE4B, amyloid-β (Aβ), CREB, BDNF, and synaptic proteins (Synapsin I, SAP 97, PSD 95) were assessed to gain insights into the possible mechanisms of action of ROF using the Western blot technique. Results show that ROF reversed SD-induced cognitive decline in mice. ROF downregulated PDE4B and Aβ expressions in the brain. Additionally, ROF improved the cAMP level and the protein expressions of synapsin I, SAP 97, and PSD 95 in the hippocampal region of SD mice. Taken together, these results suggest that ROF can suppress the deleterious effects of SD-induced cognitive dysfunction via the PDE4B-mediated cAMP/CREB/BDNF signaling cascade.
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Sanders O, Rajagopal L. Phosphodiesterase Inhibitors for Alzheimer's Disease: A Systematic Review of Clinical Trials and Epidemiology with a Mechanistic Rationale. J Alzheimers Dis Rep 2020; 4:185-215. [PMID: 32715279 PMCID: PMC7369141 DOI: 10.3233/adr-200191] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/17/2020] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Preclinical studies, clinical trials, and reviews suggest increasing 3',5'-cyclic adenosine monophosphate (cAMP) and 3',5'-cyclic guanosine monophosphate (cGMP) with phosphodiesterase inhibitors is disease-modifying in Alzheimer's disease (AD). cAMP/protein kinase A (PKA) and cGMP/protein kinase G (PKG) signaling are disrupted in AD. cAMP/PKA and cGMP/PKG activate cAMP response element binding protein (CREB). CREB binds mitochondrial and nuclear DNA, inducing synaptogenesis, memory, and neuronal survival gene (e.g., brain-derived neurotrophic factor) and peroxisome proliferator-activated receptor-γ coactivator-1α (PGC1α). cAMP/PKA and cGMP/PKG activate Sirtuin-1, which activates PGC1α. PGC1α induces mitochondrial biogenesis and antioxidant genes (e.g.,Nrf2) and represses BACE1. cAMP and cGMP inhibit BACE1-inducing NFκB and tau-phosphorylating GSK3β. OBJECTIVE AND METHODS We review efficacy-testing clinical trials, epidemiology, and meta-analyses to critically investigate whether phosphodiesteraseinhibitors prevent or treat AD. RESULTS Caffeine and cilostazol may lower AD risk. Denbufylline and sildenafil clinical trials are promising but preliminary and inconclusive. PF-04447943 and BI 409,306 are ineffective. Vinpocetine, cilostazol, and nicergoline trials are mixed. Deprenyl/selegiline trials show only short-term benefits. Broad-spectrum phosphodiesterase inhibitor propentofylline has been shown in five phase III trials to improve cognition, dementia severity, activities of daily living, and global assessment in mild-to-moderate AD patients on multiple scales, including the ADAS-Cogand the CIBIC-Plus in an 18-month phase III clinical trial. However, two books claimed based on a MedScape article an 18-month phase III trial failed, so propentofylline was discontinued. Now, propentofylline is used to treat canine cognitive dysfunction, which, like AD, involves age-associated wild-type Aβ deposition. CONCLUSION Phosphodiesterase inhibitors may prevent and treat AD.
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Inhibition of plaque progression and promotion of plaque stability by glucagon-like peptide-1 receptor agonist: Serial in vivo findings from iMap-IVUS in Watanabe heritable hyperlipidemic rabbits. Atherosclerosis 2017; 265:283-291. [PMID: 28693828 DOI: 10.1016/j.atherosclerosis.2017.06.920] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 05/28/2017] [Accepted: 06/22/2017] [Indexed: 01/20/2023]
Abstract
BACKGROUND AND AIMS Glucagon-like peptide-1 (GLP-1) is thought to inhibit development of aortic atherosclerosis and plaque formation. However, whether GLP-1 stabilizes fully developed atherosclerotic plaque or alters the complicated plaque composition remains unclarified. METHODS Ten Watanabe heritable hyperlipidemic (WHHL) rabbits were divided into GLP-1 receptor agonist treatment group and control group. After confirmation of atherosclerotic plaques in brachiocephalic arteries by iMap intravascular ultrasound (iMAP-IVUS), GLP-1 receptor agonist lixisenatide was administered to WHHL rabbits at 30 nmoL/kg/day for 12 weeks by osmotic pump. An equal volume of normal saline was administered in a control group. After evaluation by iMAP-IVUS at 12 weeks, brachiocephalic arteries were harvested for pathological histological analysis. RESULTS iMAP-IVUS analysis revealed larger fibrotic plaque components and smaller necrotic and calcified plaque components in the GLP-1 group than in the control group; %fibrotic area: 66.30 ± 2.06% vs. 75.14 ± 2.62%, p < 0.01, %necrotic area: 23.25 ± 1.87% vs. 16.17 ± 2.27%, p = 0.02, %calcified area: 2.15 ± 0.24% vs. 1.00 ± 0.18%, p < 0.01), indicating that GLP-1 receptor agonist might modify plaque composition and increase plaque stability. Histological analysis confirmed that GLP-1 receptor agonist treatment improved smooth muscle cell (SMC)-rich plaque with increased fibrotic content. Furthermore, plaque macrophage infiltration and calcification were significantly reduced by GLP-1 receptor agonist treatment; %SMC area: 6.93 ± 0.31% vs. 8.14 ± 0.48%, p = 0.02; %macrophage area: 9.11 ± 0.80% vs. 6.19 ± 0.85%, p < 0.01; %fibrotic area: 54.75 ± 1.63% vs. 69.60 ± 2.12%, p = 0.02; %calcified area: 3.25 ± 0.67% vs. 0.75 ± 0.15%, p = 0.02). CONCLUSIONS GLP-1 receptor agonist inhibited plaque progression and promoted plaque stabilization by inhibiting plaque growth and modifying plaque composition.
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Owona BA, Zug C, Schluesener HJ, Zhang ZY. Protective Effects of Forskolin on Behavioral Deficits and Neuropathological Changes in a Mouse Model of Cerebral Amyloidosis. J Neuropathol Exp Neurol 2016; 75:618-27. [PMID: 27251043 DOI: 10.1093/jnen/nlw043] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Indexed: 12/23/2022] Open
Abstract
The production of amyloid-β peptides in the brains of patients with Alzheimer disease (AD) may contribute to memory loss and impairments in social behavior. Here, an efficient adenylate cyclase activator, forskolin, was orally administered by gavage (100 mg/kg body weight) to 5-month-old transgenic APP/PS1 mice, which serve as an animal model of cerebral amyloidosis. Analyses of nest construction, sociability, and immunohistochemical features were used to determine the effects of forskolin treatment. After a relatively short term of treatment (10 days), forskolin-treated transgenic mice showed restored nest construction ability (p < 0.05) and their sociability (p < 0.01). There was a reduction of Aβ plaque deposition in the cortex and in the hippocampus. Furthermore, expression of transforming growth factor β, glial fibrillary acidic protein, and Iba-1 in the cortex was reduced in the forskolin-treated group, suggesting regulation of the inflammatory response mediated by activated microglia and astrocytes in the brains of the APP/PS1 mice (p < 0.01). Taken together, these findings suggest that forskolin shows neuroprotective effects in APP/PS1 Tg mice and may be a promising drug in the treatment of patients with AD.
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Affiliation(s)
- Brice Ayissi Owona
- From the Division of Immunopathology of the Nervous System, Institute of Pathology and Neuropathology, University of Tubingen, Tubingen, Germany (BAO, CZ, HJS, ZYZ).
| | - Caroline Zug
- From the Division of Immunopathology of the Nervous System, Institute of Pathology and Neuropathology, University of Tubingen, Tubingen, Germany (BAO, CZ, HJS, ZYZ)
| | - Hermann J Schluesener
- From the Division of Immunopathology of the Nervous System, Institute of Pathology and Neuropathology, University of Tubingen, Tubingen, Germany (BAO, CZ, HJS, ZYZ)
| | - Zhi-Yuan Zhang
- From the Division of Immunopathology of the Nervous System, Institute of Pathology and Neuropathology, University of Tubingen, Tubingen, Germany (BAO, CZ, HJS, ZYZ)
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Perez-Gonzalez R, Pascual C, Antequera D, Bolos M, Redondo M, Perez DI, Pérez-Grijalba V, Krzyzanowska A, Sarasa M, Gil C, Ferrer I, Martinez A, Carro E. Phosphodiesterase 7 inhibitor reduced cognitive impairment and pathological hallmarks in a mouse model of Alzheimer's disease. Neurobiol Aging 2013; 34:2133-45. [PMID: 23582662 DOI: 10.1016/j.neurobiolaging.2013.03.011] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Revised: 01/10/2013] [Accepted: 03/11/2013] [Indexed: 01/12/2023]
Abstract
Elevated levels of amyloid beta (Aβ) peptide, hyperphosphorylation of tau protein, and inflammation are pathological hallmarks in Alzheimer's disease (AD). Phosphodiesterase 7 (PDE7) regulates the inflammatory response through the cyclic adenosine monophosphate signaling cascade, and thus plays a central role in AD. The aim of this study was to evaluate the efficacy of an inhibitor of PDE7, named S14, in a mouse model of AD. We report that APP/Ps1 mice treated daily for 4 weeks with S14 show: (1) significant attenuation in behavioral impairment; (2) decreased brain Aβ deposition; (3) enhanced astrocyte-mediated Aβ degradation; and (4) decreased tau phosphorylation. These effects are mediated via the cyclic adenosine monophosphate/cyclic adenosine monophosphate response element-binding protein signaling pathway, and inactivation of glycogen synthase kinase (GSK)3. Our data support the use of PDE7 inhibitors, and specifically S14, as effective therapeutic agents for the prevention and treatment of AD.
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Affiliation(s)
- Rocio Perez-Gonzalez
- Neuroscience Group, Instituto de Investigacion Hospital 12 de Octubre (i+12), Madrid, Spain
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Gerlo S, Kooijman R, Beck IM, Kolmus K, Spooren A, Haegeman G. Cyclic AMP: a selective modulator of NF-κB action. Cell Mol Life Sci 2011; 68:3823-41. [PMID: 21744067 PMCID: PMC11114830 DOI: 10.1007/s00018-011-0757-8] [Citation(s) in RCA: 135] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2011] [Revised: 06/10/2011] [Accepted: 06/16/2011] [Indexed: 10/18/2022]
Abstract
It has been known for several decades that cyclic AMP (cAMP), a prototypical second messenger, transducing the action of a variety of G-protein-coupled receptor ligands, has potent immunosuppressive and anti-inflammatory actions. These actions have been attributed in part to the ability of cAMP-induced signals to interfere with the function of the proinflammatory transcription factor Nuclear Factor-kappaB (NF-κB). NF-κB plays a crucial role in switching on the gene expression of a plethora of inflammatory and immune mediators, and as such is one of the master regulators of the immune response and a key target for anti-inflammatory drug design. A number of fundamental molecular mechanisms, contributing to the overall inhibitory actions of cAMP on NF-κB function, are well established. Paradoxically, recent reports indicate that cAMP, via its main effector, the protein kinase A (PKA), also promotes NF-κB activity. Indeed, cAMP actions appear to be highly cell type- and context-dependent. Importantly, several novel players in the cAMP/NF-κB connection, which selectively direct cAMP action, have been recently identified. These findings not only open up exciting new research avenues but also reveal novel opportunities for the design of more selective, NF-κB-targeting, anti-inflammatory drugs.
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Affiliation(s)
- Sarah Gerlo
- VIB Department of Medical Protein Research, Ghent University (UGent), Albert Baertsoenkaai, Belgium.
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Oxidative Stress and β-Amyloid Protein in Alzheimer’s Disease. Neuromolecular Med 2011; 13:223-50. [DOI: 10.1007/s12017-011-8155-9] [Citation(s) in RCA: 158] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Accepted: 08/26/2011] [Indexed: 12/21/2022]
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Tilleux S, Hermans E. Down-regulation of astrocytic GLAST by microglia-related inflammation is abrogated in dibutyryl cAMP-differentiated cultures. J Neurochem 2010; 105:2224-36. [PMID: 18298666 DOI: 10.1111/j.1471-4159.2008.05305.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The influence of neuroinflammation on glutamate uptake by glial cells was examined after exposing primary cultures of rat astrocytes to conditioned culture medium from lipopolysaccharide-activated microglia. While such treatment triggered an inflammatory response in astrocytes, as revealed by the induction of cytokine expression, a significant decrease in GLAST expression and activity was observed after 72 h. This regulation of glutamate transporter was not observed with medium from naive microglia, but was mimicked by direct addition of tumor necrosis factor-alpha (TNF-alpha), a major cytokine released from activated microglia. Hence, on its own, TNF-alpha also triggered inflammation in astrocyte cultures, highlighting complex cross-talk between astrocytes and microglia in inflammatory conditions. This putatively detrimental regulation of GLAST in response to inflammation was also studied in cells exposed to dibutyryl cAMP, recognized as a model of astrocytes exhibiting a typical differentiated or activated phenotype. In this model, the conditioned culture medium from activated microglia, as well as TNF-alpha, were found to increase glutamate uptake capacity. Consistently, both of these treatments caused only modest induction of an inflammatory response in dibutyryl cAMP-matured astrocytes as compared to undifferentiated astrocytes. Together, these results suggest that differentiated/activated astrocytes are endowed with the capacity to confront inflammatory insults and that drugs influencing the astrocytes phenotype would deserve further consideration in the treatment of neurological disorders.
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Affiliation(s)
- Sébastien Tilleux
- Laboratoire de Pharmacologie Expérimentale, Université Catholique de Louvain, Brussels, Belgium
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Arakawa M, Mita T, Azuma K, Ebato C, Goto H, Nomiyama T, Fujitani Y, Hirose T, Kawamori R, Watada H. Inhibition of monocyte adhesion to endothelial cells and attenuation of atherosclerotic lesion by a glucagon-like peptide-1 receptor agonist, exendin-4. Diabetes 2010; 59:1030-7. [PMID: 20068138 PMCID: PMC2844811 DOI: 10.2337/db09-1694] [Citation(s) in RCA: 395] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVE Exogenous administration of glucagon-like peptide-1 (GLP-1) or GLP-1 receptor agonists such as an exendin-4 has direct beneficial effects on the cardiovascular system. However, their effects on atherosclerogenesis have not been elucidated. The aim of this study was to investigate the effects of GLP-1 on accumulation of monocytes/macrophages on the vascular wall, one of the earliest steps in atherosclerogenesis. RESEARCH DESIGN AND METHODS After continuous infusion of low (300 pmol . kg(-1) . day(-1)) or high (24 nmol . kg(-1) . day(-1)) dose of exendin-4 in C57BL/6 or apolipoprotein E-deficient mice (apoE(-/-)), we evaluated monocyte adhesion to the endothelia of thoracic aorta and arteriosclerotic lesions around the aortic valve. The effects of exendin-4 were investigated in mouse macrophages and human monocytes. RESULTS Treatment with exendin-4 significantly inhibited monocytic adhesion in the aortas of C57BL/6 mice without affecting metabolic parameters. In apoE(-/-) mice, the same treatment reduced monocyte adhesion to the endothelium and suppressed atherosclerogenesis. In vitro treatment of mouse macrophages with exendin-4 suppressed lipopolysaccharide-induced mRNA expression of tumor necrosis factor-alpha and monocyte chemoattractant protein-1, and suppressed nuclear translocation of p65, a component of nuclear factor-kappaB. This effect was reversed by either MDL-12330A, a cAMP inhibitor or PKI(14-22), a protein kinase A-specific inhibitor. In human monocytes, exendin-4 reduced the expression of CD11b. CONCLUSIONS Our data suggested that GLP-1 receptor agonists reduced monocyte/macrophage accumulation in the arterial wall by inhibiting the inflammatory response in macrophages, and that this effect may contribute to the attenuation of atherosclerotic lesion by exendin-4.
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Affiliation(s)
- Masayuki Arakawa
- Department of Medicine, Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Tomoya Mita
- Department of Medicine, Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan
- Corresponding author: Tomoya Mita, , or Hirotaka Watada,
| | - Kosuke Azuma
- Department of Medicine, Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Chie Ebato
- Department of Medicine, Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Hiromasa Goto
- Department of Medicine, Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Takashi Nomiyama
- Department of Medicine, Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Yoshio Fujitani
- Department of Medicine, Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan
- Center for Therapeutic Innovations in Diabetes, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Takahisa Hirose
- Department of Medicine, Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan
- Center for Therapeutic Innovations in Diabetes, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Ryuzo Kawamori
- Department of Medicine, Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan
- Center for Therapeutic Innovations in Diabetes, Juntendo University Graduate School of Medicine, Tokyo, Japan
- Sportology Center, Juntendo University Graduate School of Medicine, Tokyo, Japan
- Center for Beta Cell Biology and Regeneration, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Hirotaka Watada
- Department of Medicine, Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan
- Sportology Center, Juntendo University Graduate School of Medicine, Tokyo, Japan
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Mogi C, Tobo M, Tomura H, Murata N, He XD, Sato K, Kimura T, Ishizuka T, Sasaki T, Sato T, Kihara Y, Ishii S, Harada A, Okajima F. Involvement of proton-sensing TDAG8 in extracellular acidification-induced inhibition of proinflammatory cytokine production in peritoneal macrophages. THE JOURNAL OF IMMUNOLOGY 2009; 182:3243-51. [PMID: 19234222 DOI: 10.4049/jimmunol.0803466] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Extracellular acidification inhibited LPS-induced TNF-alpha protein production, which was associated with an inhibition of TNF-alpha mRNA expression, in mouse peritoneal macrophages. The LPS-induced cytokine production was also inhibited by G(s) protein-coupled receptor agonists prostaglandin E(1) and isoproterenol. Among OGR1 family proton-sensing GTP-binding regulatory protein-coupled receptors, TDAG8, OGR1, and G2A are expressed in the cells. The inhibitory action by acidic pH on TNF-alpha production was significantly attenuated in macrophages from TDAG8(Tp/Tp) mice but not in those from OGR1(geo/geo) mice. Moreover, small interfering RNA specific to TDAG8, but not to G2A, clearly attenuated the acidification-induced inhibition of TNF-alpha production. On the other hand, the down-regulation or deficiency of TDAG8 hardly affected prostaglandin E(1)- or isoproterenol-induced actions. LPS-induced IL-6 production was also inhibited by extracellular acidification in a manner that was sensitive to TDAG8 expression. The acidic pH-induced inhibitory action on the cytokine production was significantly reversed either by a small interfering RNA specific to G(s) proteins or by a protein kinase A (PKA)-specific inhibitor H89. Indeed, a PKA-specific cAMP derivative inhibited LPS-induced cytokine production. Moreover, acidification induced cAMP accumulation in a TDAG8-specific way. We conclude that TDAG8, at least partly, mediates the extracellular acidification-induced inhibition of proinflammatory cytokine production through the G(s) protein/cAMP/PKA signaling pathway in mouse macrophages.
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Affiliation(s)
- Chihiro Mogi
- Laboratory of Signal Transduction, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Japan
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Tilleux S, Goursaud S, Hermans E. Selective up-regulation of GLT-1 in cultured astrocytes exposed to soluble mediators released by activated microglia. Neurochem Int 2009; 55:35-40. [PMID: 19428805 DOI: 10.1016/j.neuint.2008.12.021] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2008] [Revised: 12/09/2008] [Accepted: 12/12/2008] [Indexed: 11/28/2022]
Abstract
Impaired glial glutamate uptake is commonly involved in neuronal damages observed in acute and chronic nervous disorders. As nervous insults are frequently associated with local inflammation involving microglia, this study aims at exploring the link between activated microglia and altered glutamate uptake in astrocytes. The regulation of the expression and activity of type 1 glutamate transporter (GLT-1) was examined after exposing cultures of rat astrocytes to conditioned medium from lipopolysaccharide-activated microglia cultures. Significant increases in GLT-1 mRNA expression and dihydrokainate sensitive uptake of aspartate were observed after 72h of treatment. These effects were reproduced by direct exposure of the astrocyte cultures to tumor necrosis factor alpha, a major cytokine released by activated microglia. The regulation of GLT-1 activity in response to inflammatory stimuli was also evidenced in cells exposed to dibutyryl cAMP, recognised as a model of reactive astrocytes in which the expression of this glutamate transporter is constitutively enhanced. Taken together, these results suggest that the GLT-1-dependent control of glutamate neurotransmission by either naive or chemically activated astrocytes is influenced by microglia-mediated inflammation.
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Affiliation(s)
- Sébastien Tilleux
- Laboratoire de Pharmacologie Expérimentale, Université catholique de Louvain, Brussels, Belgium
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Ezoulin M, Liu Z, Dutertre-Catella H, Wu G, Dong C, Heymans F, Ombetta J, Rat P, Massicot F. A new acetylcholinesterase inhibitor with anti-PAF activity modulates oxidative stress and pro-inflammatory mediators release in stimulated RAW 264.7 macrophage cells. Comparison with tacrine. Int Immunopharmacol 2007; 7:1685-94. [DOI: 10.1016/j.intimp.2007.08.023] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2007] [Revised: 08/28/2007] [Accepted: 08/30/2007] [Indexed: 10/22/2022]
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13
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Myhre AE, Lyngstadaas SP, Dahle MK, Stuestøl JF, Foster SJ, Thiemermann C, Lilleaasen P, Wang JE, Aasen AO. Anti-inflammatory properties of enamel matrix derivative in human blood. J Periodontal Res 2006; 41:208-13. [PMID: 16677290 DOI: 10.1111/j.1600-0765.2005.00863.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND AND OBJECTIVE Enamel matrix derivative (EMD), extracted from porcine tooth buds, has been shown to promote periodontal healing in patients with severe periodontitis. This involves modulation of the inflammatory response followed by the onset of periodontal regeneration. Based on these observations, we examined the ability of EMD to modulate the release of a pro-inflammatory cytokine [tumor necrosis factor (TNF)-alpha], an anti-inflammatory cytokine (interleukin-10) and a chemokine (interleukin- 8) in whole human blood challenged by bacterial cell wall components. MATERIAL AND METHODS Whole blood from healthy donors was challenged by lipopolysaccharide or peptidoglycan and incubated with different concentrations of EMD or a cAMP analogue 8-(4-chlorophenyl)thio-cAMP (8-CPT-cAMP). TNF-alpha, interleukin-8 and interleukin-10 were analysed from plasma by enzyme-linked immunosorbent assay (ELISA) while cAMP levels of peripheral blood mononuclear cell lysates were analysed by enzyme immunoassay (EIA). RESULTS We found that EMD attenuated the release of TNF-alpha and interleukin-8 in whole blood from healthy donors challenged by lipopolysaccharide or peptidoglycan, while the release of interleukin-10 was unchanged. Enamel matrix derivative also produced a four-fold increase in the cAMP levels of peripheral blood mononuclear cell lysates. Like EMD, 8-CPT-cAMP attenuated the formation of TNF-alpha, but not of interleukin-10, in blood challenged by lipopolysaccharide. CONCLUSION Enamel matrix derivative limits the release of pro-inflammatory cytokines induced by lipopolysaccharide or peptidoglycan in human blood, suggesting that it has anti-inflammatory properties. We propose that this effect of EMD is, at least partly, secondary to an increase in the intracellular levels of cAMP in peripheral blood mononuclear cells.
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Affiliation(s)
- A E Myhre
- Faculty Division Rikshospitalet Institute for Surgical Research, University of Oslo, Oslo, Norway.
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Mishima K, Baba A, Matsuo M, Itoh Y, Oishi R. Protective effect of cyclic AMP against cisplatin-induced nephrotoxicity. Free Radic Biol Med 2006; 40:1564-77. [PMID: 16632117 DOI: 10.1016/j.freeradbiomed.2005.12.025] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2005] [Revised: 11/22/2005] [Accepted: 12/22/2005] [Indexed: 11/18/2022]
Abstract
We reported earlier that reactive oxygen species are implicated in necrotic injury induced by a transient exposure of cultured renal tubular cells to a high concentration of cisplatin but not in apoptosis occurring after continuous exposure to a low concentration of cisplatin. We report here the protective effect of cyclic AMP against cisplatin-induced necrosis in cultured renal tubular cells as well as cisplatin-induced acute renal failure in rats. Several pharmacological agents that stimulate cyclic AMP signaling, including the nonhydrolyzable cyclic AMP analogue dibutyryl cyclic AMP, forskolin, 3-isobutyl-1-methylxanthine, and a prostacyclin analogue, beraprost, prevented cisplatin-induced cell injury in a protein kinase A-dependent manner. Cisplatin enhanced lipid peroxidation, decreased CuZn superoxide dismutase (SOD) while enhancing MnSOD activity, and increased cellular tumor necrosis factor-alpha (TNF-alpha) content. The elevation of TNF-alpha content and cell injury induced by cisplatin were attenuated by p38 mitogen-activated protein kinase (MAPK) inhibitors including SB203580 and PD169316. Indeed, cisplatin increased the number of phosphorylated p38 MAPK-like immunoreactive cells. These intracellular events were all reversed by antioxidants such as N-acetylcysteine (NAC) and glutathione or cyclic AMP analogues. The in vivo acute renal injury after cisplatin injection was associated with the elevation of renal TNF-alpha content. The cisplatin-induced renal injury and the increase in TNF-alpha content were reversed by NAC or beraprost. These findings suggest that cyclic AMP protects renal tubular cells against cisplatin-induced oxidative injury by obliterating reactive oxygen species and subsequent inhibition of TNF-alpha synthesis through blockade of p38 MAPK activation.
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Affiliation(s)
- Kazuto Mishima
- Department of Pharmacy, Kyushu University Hospital 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
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Lee EO, Shin YJ, Chong YH. Mechanisms involved in prostaglandin E2-mediated neuroprotection against TNF-α: possible involvement of multiple signal transduction and β-catenin/T-cell factor. J Neuroimmunol 2004; 155:21-31. [PMID: 15342193 DOI: 10.1016/j.jneuroim.2004.05.012] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2004] [Revised: 05/05/2004] [Accepted: 05/27/2004] [Indexed: 11/20/2022]
Abstract
Cerebrospinal fluid prostaglandin E2 (PGE2) and tumor necrosis factor-alpha (TNF-alpha) levels are elevated in patients with Alzheimer's disease (AD), which suggests that they are involved in neurodegeneration. We previously reported that TNF-alpha derived from human macrophages, in response to beta-amyloid or amyloidogenic C-terminal peptide, is a main mediator of inflammatory neurotoxicity. In a continuation of this work, the present study investigated the direct effect of PGE2, one of the major prostaglandins produced in the brain, on cell viability in SH-SY5Y neuronal cells treated with TNF-alpha. PGE2 did not promote neurotoxicity, but rather had a strong protective effect against TNF-alpha by ameliorating TNF-alpha-induced apoptosis and also by rescuing the intracellular level of beta-catenin, a key transducer of the Wnt signaling pathway. PGE2-mediated stabilization of beta-catenin was accompanied by T-cell factor/lymphoid enhancer factor (Tcf/Lef)-mediated transcriptional activation, which was followed by an increase in the cyclinD1 level. Pharmacological studies provided further evidence supporting the notion that PGE2-mediated neuroprotection against TNF-alpha involves the stimulation of Tcf/Lef signaling through EP1-, EP2-, and EP4-mediated increases of beta-catenin in SH-SY5Y cells. In addition, this PGE2 effect appears to be dependent on the activation of protein kinase A, phosphatidylinositol 3-kinase, phospholipase C, and to a lesser extent protein kinase C. Thus, the molecular mechanism governing the inhibitory effect of PGE2 against TNF-alpha may involve the activation and cross talk of multiple signal transduction and play an important role in regulating the survival of neurons during the neurotoxic inflammatory response associated with neurodegenerative diseases including AD.
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Affiliation(s)
- Eun Ok Lee
- Department of Microbiology, College of Medicine, Division of Molecular Biology and Neuroscience, Ewha Medical Research Institute, Ewha Womans University, 911-1, Mok-6-dong, Yangcheonku, Seoul, 158-710, South Korea
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Wang JE, Dahle MK, McDonald M, Foster SJ, Aasen AO, Thiemermann C. Peptidoglycan and lipoteichoic acid in gram-positive bacterial sepsis: receptors, signal transduction, biological effects, and synergism. Shock 2004; 20:402-14. [PMID: 14560103 DOI: 10.1097/01.shk.0000092268.01859.0d] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In sepsis and multiple organ dysfunction syndrome (MODS) caused by gram-negative bacteria, lipopolysaccharide (LPS) initiates the early signaling events leading to the deleterious inflammatory response. However, it has become clear that LPS can not reproduce all of the clinical features of sepsis, which emphasize the roles of other contributing factors. Gram-positive bacteria, which lack LPS, are today responsible for a substantial part of the incidents of sepsis with MODS. The major wall components of gram-positive bacteria, peptidoglycan and lipoteichoic acid, are thought to contribute to the development of sepsis and MODS. In this review, the literature underlying our current understanding of how peptidoglycan and lipoteichoic acid activate inflammatory responses will be presented, with a focus on recent advances in this field.
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Affiliation(s)
- Jacob E Wang
- The William Harvey Research Institute, Charterhouse Square, London EC1M 6BC, United Kingdom.
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Chong YH, Shin YJ, Suh YH. Cyclic AMP inhibition of tumor necrosis factor alpha production induced by amyloidogenic C-terminal peptide of Alzheimer's amyloid precursor protein in macrophages: involvement of multiple intracellular pathways and cyclic AMP response element binding protein. Mol Pharmacol 2003; 63:690-8. [PMID: 12606779 DOI: 10.1124/mol.63.3.690] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
In the present study, we focused on the molecular events involved in tumor necrosis factor-alpha (TNF-alpha) production in response to the amyloidogenic 105-amino acid carboxyl-terminal fragment (CT105) of amyloid precursor protein, a candidate alternative toxic element in Alzheimer's disease pathology, and the mechanisms by which cyclic AMP regulates the relating inflammatory signal cascades. CT105 at nanomolar concentrations strongly activated multiple signaling pathways involving tyrosine kinase-dependent extracellular signal-regulated kinase and p38 mitogen-activated protein kinases. Moreover, phosphatidylinositol 3-kinase/Akt signal was required for excess TNF-alpha production in human macrophages derived from THP-1 cells. Interferon-gamma significantly potentiated the induction of the CT105-mediated signal cascade. These multiple signaling pathways in turn converged, at least in part, at the nuclear transcription factor known as cAMP response element binding protein (CREB), which acts on the TNF-alpha gene promoter through the cAMP response element. The cell-permeable cAMP analog dibutyryl cAMP partially and almost simultaneously suppressed all of these CT105-induced signaling pathways through excessive CREB phosphorylation, which led to decreased CREB DNA binding activity and reduced TNF-alpha expression. Furthermore, dibutyryl cAMP decreased the interaction of the p65 nuclear factor-kappa B with CREB binding protein, thus further inhibiting CT105-mediated TNF-alpha expression. Collectively, the detailed molecular mechanisms of amyloidogenic CT-induced TNF-alpha production as negatively regulated by cAMP may advance the possibility of targeted treatment in Alzheimer's disease.
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Affiliation(s)
- Young Hae Chong
- Department of Microbiology, College of Medicine, Division of Molecular Biology and Neuroscience, Medical Research Center, Ewha Womans University, Seoul, Korea.
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