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Li YF, Ren X, Zhang L, Wang YH, Chen T. Microglial polarization in TBI: Signaling pathways and influencing pharmaceuticals. Front Aging Neurosci 2022; 14:901117. [PMID: 35978950 PMCID: PMC9376354 DOI: 10.3389/fnagi.2022.901117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 06/28/2022] [Indexed: 11/13/2022] Open
Abstract
Traumatic brain injury (TBI) is a serious disease that threatens life and health of people. It poses a great economic burden on the healthcare system. Thus, seeking effective therapy to cure a patient with TBI is a matter of great urgency. Microglia are macrophages in the central nervous system (CNS) and play an important role in neuroinflammation. When TBI occurs, the human body environment changes dramatically and microglia polarize to one of two different phenotypes: M1 and M2. M1 microglia play a role in promoting the development of inflammation, while M2 microglia play a role in inhibiting inflammation. How to regulate the polarization direction of microglia is of great significance for the treatment of patients with TBI. The polarization of microglia involves many cellular signal transduction pathways, such as the TLR-4/NF-κB, JAK/STAT, HMGB1, MAPK, and PPAR-γ pathways. These provide a theoretical basis for us to seek therapeutic drugs for the patient with TBI. There are several drugs that target these pathways, including fingolimod, minocycline, Tak-242 and erythropoietin (EPO), and CSF-1. In this study, we will review signaling pathways involved in microglial polarization and medications that influence this process.
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Affiliation(s)
| | | | | | - Yu-Hai Wang
- Department of Neurosurgery, The 904th Hospital of PLA, Medical School of Anhui Medical University, Wuxi, China
| | - Tao Chen
- Department of Neurosurgery, The 904th Hospital of PLA, Medical School of Anhui Medical University, Wuxi, China
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Li G, Kidd J, Gehr TWB, Li PL. Podocyte Sphingolipid Signaling in Nephrotic Syndrome. Cell Physiol Biochem 2021; 55:13-34. [PMID: 33861526 PMCID: PMC8193717 DOI: 10.33594/000000356] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/29/2021] [Indexed: 11/25/2022] Open
Abstract
Podocytes play a vital role in the pathogenesis of nephrotic syndrome (NS), which is clinically characterized by heavy proteinuria, hypoalbuminemia, hyperlipidemia, and peripheral edema. The pathogenesis of NS has evolved through several hypotheses ranging from immune dysregulation theory and increased glomerular permeability theory to the current concept of podocytopathy. Podocytopathy is characterized by dysfunction or depletion of podocytes, which may be caused by unknown permeability factor, genetic disorders, drugs, infections, systemic disorders, and hyperfiltration. Over the last two decades, numerous studies have been done to explore the molecular mechanisms of podocyte injuries or NS and to develop the novel therapeutic strategies targeting podocytopathy for treatment of NS. Recent studies have shown that normal sphingolipid metabolism is essential for structural and functional integrity of podocytes. As a basic component of the plasma membrane, sphingolipids not only support the assembly of signaling molecules and interaction of receptors and effectors, but also mediate various cellular activities, such as apoptosis, proliferation, stress responses, necrosis, inflammation, autophagy, senescence, and differentiation. This review briefly summarizes current evidence demonstrating the regulation of sphingolipid metabolism in podocytes and the canonical or noncanonical roles of podocyte sphingolipid signaling in the pathogenesis of NS and associated therapeutic strategies.
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Affiliation(s)
- Guangbi Li
- Department of Pharmacology and Toxicology, School of Medicine, Virginia Commonwealth University, Richmond, VA, USA
| | - Jason Kidd
- Division of Nephrology, School of Medicine, Virginia Commonwealth University, Richmond, VA, USA
| | - Todd W B Gehr
- Division of Nephrology, School of Medicine, Virginia Commonwealth University, Richmond, VA, USA
| | - Pin-Lan Li
- Department of Pharmacology and Toxicology, School of Medicine, Virginia Commonwealth University, Richmond, VA, USA,
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Whetton AD, Azmi NC, Pearson S, Jaworska E, Zhang L, Blance R, Kendall AC, Nicolaou A, Taylor S, Williamson AJ, Pierce A. MPL W515L expression induces TGFβ secretion and leads to an increase in chemokinesis via phosphorylation of THOC5. Oncotarget 2016; 7:10739-55. [PMID: 26919114 PMCID: PMC4905435 DOI: 10.18632/oncotarget.7639] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 02/15/2016] [Indexed: 02/03/2023] Open
Abstract
The thrombopoietin receptor (MPL) has been shown to be mutated (MPL W515L) in myelofibrosis and thrombocytosis yet new approaches to treat this disorder are still required. We have previously shown that transcriptome and proteomic effects do not correlate well in oncogene-mediated leukemogenesis. We therefore investigated the effects of MPL W515L using proteomics. The consequences of MPL W515L expression on over 3300 nuclear and 3500 cytoplasmic proteins were assessed using relative quantification mass spectrometry. We demonstrate that MPL W515L expression markedly modulates the CXCL12/CXCR4/CD45 pathway associated with stem and progenitor cell chemotactic movement. We also demonstrated that MPL W515L expressing cells displayed increased chemokinesis which required the MPL W515L-mediated dysregulation of MYC expression via phosphorylation of the RNA transport protein THOC5 on tyrosine 225. In addition MPL W515L expression induced TGFβ secretion which is linked to sphingosine 1-phosphate production and the increased chemokinesis. These studies identify several pathways which offer potential targets for therapeutic intervention in the treatment of MPL W515L-driven malignancy. We validate our approach by showing that CD34+ cells from MPL W515L positive patients display increased chemokinesis and that treatment with a combination of MYC and sphingosine kinase inhibitors leads to the preferential killing of MPL W515L expressing cells.
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Affiliation(s)
- Anthony D. Whetton
- Stem Cell and Leukaemia Proteomics Laboratory, The University of Manchester, Manchester, UK
| | - Norhaida Che Azmi
- Stem Cell and Leukaemia Proteomics Laboratory, The University of Manchester, Manchester, UK
| | - Stella Pearson
- Stem Cell and Leukaemia Proteomics Laboratory, The University of Manchester, Manchester, UK
| | - Ewa Jaworska
- Stem Cell and Leukaemia Proteomics Laboratory, The University of Manchester, Manchester, UK
| | - Liqun Zhang
- Stem Cell and Leukaemia Proteomics Laboratory, The University of Manchester, Manchester, UK
| | - Rognvald Blance
- Stem Cell and Leukaemia Proteomics Laboratory, The University of Manchester, Manchester, UK
| | - Alexandra C. Kendall
- Manchester Pharmacy School, Faculty of Medical and Human Sciences, Manchester Academic Health Science Centre, The University of Manchester, Manchester, UK
| | - Anna Nicolaou
- Manchester Pharmacy School, Faculty of Medical and Human Sciences, Manchester Academic Health Science Centre, The University of Manchester, Manchester, UK
| | - Samuel Taylor
- Stem Cell and Leukaemia Proteomics Laboratory, The University of Manchester, Manchester, UK
| | - Andrew J.K. Williamson
- Stem Cell and Leukaemia Proteomics Laboratory, The University of Manchester, Manchester, UK
| | - Andrew Pierce
- Stem Cell and Leukaemia Proteomics Laboratory, The University of Manchester, Manchester, UK
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Bolli MH, Abele S, Birker M, Bravo R, Bur D, de Kanter R, Kohl C, Grimont J, Hess P, Lescop C, Mathys B, Müller C, Nayler O, Rey M, Scherz M, Schmidt G, Seifert J, Steiner B, Velker J, Weller T. Novel S1P(1) receptor agonists--part 3: from thiophenes to pyridines. J Med Chem 2013; 57:110-30. [PMID: 24367923 DOI: 10.1021/jm4014696] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
In preceding communications we summarized our medicinal chemistry efforts leading to the identification of potent, selective, and orally active S1P1 agonists such as the thiophene derivative 1. As a continuation of these efforts, we replaced the thiophene in 1 by a 2-, 3-, or 4-pyridine and obtained less lipophilic, potent, and selective S1P1 agonists (e.g., 2) efficiently reducing blood lymphocyte count in the rat. Structural features influencing the compounds' receptor affinity profile and pharmacokinetics are discussed. In addition, the ability to penetrate brain tissue has been studied for several compounds. As a typical example for these pyridine based S1P1 agonists, compound 53 showed EC50 values of 0.6 and 352 nM for the S1P1 and S1P3 receptor, respectively, displayed favorable PK properties, and penetrated well into brain tissue. In the rat, compound 53 maximally reduced the blood lymphocyte count for at least 24 h after oral dosing of 3 mg/kg.
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Affiliation(s)
- Martin H Bolli
- Drug Discovery Chemistry, Actelion Pharmaceuticals Ltd. , Gewerbestrasse 16, CH-4123 Allschwil, Switzerland
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Abstract
Sphingosine-1-phosphate (S1P) plays crucial roles in the regulation of cell growth, proliferation, differentiation, cell survival, migration, and angiogenesis. In the reproductive system, S1P protects mammalian germ cells from irradiation or chemotherapy-induced cell death in vivo and in vitro. Moreover, S1P could improve the survival rate of thawed ovary and transplanted ovary. Furthermore, S1P could improve the developmental potential of oocyte and preimplantation embryo. In conclusion, S1P plays important roles in reproduction.
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Affiliation(s)
- Lei Guo
- 1Department of Obstetrics and Gynecology, Center for Reproductive Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, China
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Böhm A, Flößer A, Ermler S, Fender AC, Lüth A, Kleuser B, Schrör K, Rauch BH. Factor-Xa-induced mitogenesis and migration require sphingosine kinase activity and S1P formation in human vascular smooth muscle cells. Cardiovasc Res 2013; 99:505-13. [PMID: 23658376 DOI: 10.1093/cvr/cvt112] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
AIMS Sphingosine-1-phosphate (S1P) is a cellular signalling lipid generated by sphingosine kinase-1 (SPHK1). The aim of the study was to investigate whether the activated coagulation factor-X (FXa) regulates SPHK1 transcription and the formation of S1P and subsequent mitogenesis and migration of human vascular smooth muscle cells (SMC). METHODS AND RESULTS FXa induced a time- (3-6 h) and concentration-dependent (3-30 nmol/L) increase of SPHK1 mRNA and protein expression in human aortic SMC, resulting in an increased synthesis of S1P. FXa-stimulated transcription of SPHK1 was mediated by the protease-activated receptor-1 (PAR-1) and PAR-2. In human carotid artery plaques, expression of SPHK1 was observed at SMC-rich sites and was co-localized with intraplaque FX/FXa content. FXa-induced SPHK1 transcription was attenuated by inhibitors of Rho kinase (Y27632) and by protein kinase C (PKC) isoforms (GF109203X). In addition, FXa rapidly induced the activation of the small GTPase Rho A. Inhibition of signalling pathways which regulate SPHK1 expression, inhibition of its activity or siRNA-mediated SPHK1 knockdown attenuated the mitogenic and chemotactic response of human SMC to FXa. CONCLUSION These data suggest that FXa induces SPHK1 expression and increases S1P formation independent of thrombin and that this involves the activation of Rho A and PKC signalling. In addition to its key function in coagulation, this direct effect of FXa on human SMC may increase cell proliferation and migration at sites of vessel injury and thereby contribute to the progression of vascular lesions.
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Affiliation(s)
- Andreas Böhm
- Institut für Pharmakologie, Abteilung Allgemeine Pharmakologie, Universitätsmedizin Greifswald, Felix-Hausdorff-Str. 3, Greifswald, Germany
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Canals D, Roddy P, Hannun YA. Protein phosphatase 1α mediates ceramide-induced ERM protein dephosphorylation: a novel mechanism independent of phosphatidylinositol 4, 5-biphosphate (PIP2) and myosin/ERM phosphatase. J Biol Chem 2012; 287:10145-10155. [PMID: 22311981 DOI: 10.1074/jbc.m111.306456] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
ERM (ezrin, radixin, and moesin) proteins are cytoskeletal interacting proteins that bind cortical actin, the plasma membrane, and membrane proteins, which are found in specialized plasma membrane structures such as microvilli and filopodia. ERM proteins are regulated by phosphatidylinositol 4, 5-biphosphate (PIP(2)) and by phosphorylation of a C-terminal threonine, and its inactivation involves PIP(2) hydrolysis and/or myosin phosphatase (MP). Recently, we demonstrated that ERM proteins are also subject to counter regulation by the bioactive sphingolipids ceramide and sphingosine 1-phosphate. Plasma membrane ceramide induces ERM dephosphorylation whereas sphingosine 1-phosphate induces their phosphorylation. In this work, we pursue the mechanisms by which ceramide regulates dephosphorylation. We found that this dephosphorylation was independent of hydrolysis and localization of PIP(2) and MP. However, the results show that ERM dephosphorylation was blocked by treatment with protein phosphatase 1 (PP1) pharmacological inhibitors and specifically by siRNA to PP1α, whereas okadaic acid, a PP2A inhibitor, failed. Moreover, a catalytic inactive mutant of PP1α acted as dominant negative of the endogenous PP1α. Additional results showed that the ceramide mechanism of PP1α activation is largely independent of PIP(2) hydrolysis and MP. Taken together, these results demonstrate a novel, acute mechanism of ERM regulation dependent on PP1α and plasma membrane ceramide.
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Affiliation(s)
- Daniel Canals
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Patrick Roddy
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Yusuf A Hannun
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina 29425.
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Ong A, Orozco F, Sheikh ES, Anmuth C, Alfaro A, Kathrins R, Grove GL, Zerweck C, Madden AM, Raspa R, Weis MT. An RCT on the effects of topical CGP on surgical wound appearance and residual scarring in bilateral total-knee arthroplasty patients. J Wound Care 2012; 20:592-8. [PMID: 22240886 DOI: 10.12968/jowc.2011.20.12.592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To test the hypothesis that topically applied calcium glycerophosphate (CGP) would improve the appearance of the wound following bilateral knee replacement. METHOD Healthy patients, aged 45-75 years, scheduled for bilateral total-knee replacement surgery were recruited into the study. One knee was randomly assigned to the treatment group, while the contralateral knee was designated the control (standard care). Subjects were instructed to apply a preparation of 10% CGP in an aqueous lotion to the treated knee once daily for 42 days, starting at the third postoperative day. Functional sealing and cosmetic appearance of the incision were evaluated by two surgeons by direct examination of the patient and then by two experienced assessors from photographs. The investigators qualitatively scored the intensity and extent of erythema along the incision and over the entire knee, the appearance of visible oedema along the incision and over the knee, and the overall clinical impression of wound healing. All four assessors were blinded to the subjects' allocation and the latter two assessors to the initial investigators' assessments. Subjects were also followed up for an additional 46 weeks, giving a total study duration of 12 months. RESULTS Twenty patients completed the study. Statistical analysis showed that both the area and intensity of erythema along the incision were significantly reduced in the treated vs untreated knee over the entire study period. The analysis further showed that treatment significantly reduced oedema, both along the incision and across the entire knee. The differences were most marked at the seventh postoperative day and diminished with time. No adverse effects were observed for any patient, in either treated or untreated knees. CONCLUSION These data demonstrate that postoperative application of 10% CGP could improve the appearance of the wound following total knee arthroplasty.
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Affiliation(s)
- A Ong
- Rothman Institute, Philadelphia, USA
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Bode C, Gräler MH. Quantification of sphingosine-1-phosphate and related sphingolipids by liquid chromatography coupled to tandem mass spectrometry. Methods Mol Biol 2012; 874:33-44. [PMID: 22528437 DOI: 10.1007/978-1-61779-800-9_3] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Liquid chromatography coupled to tandem mass spectrometry has evolved as the method of choice for the detection of sphingolipid metabolites due to its high sensitivity and superior specificity compared to other methodological approaches. Here, we describe a simple and robust method for the detection and quantification of sphingosine-1-phosphate (S1P) and related sphingolipids in biological samples. Tissue homogenates, cells, supernatant, plasma, and whole blood are spiked with an internal standard to account for loss of material during sample handling. After chloroform extraction of lipids under acidified conditions, the solvent is evaporated, and the remaining lipid extracts are dissolved in 20% CHCl(3) and 80% methanol. Following reversed-phase high-performance liquid chromatography step-gradient separation of sphingolipids and positive electrospray ionization, detection is carried out with the AB Sciex QTrap triple-quadrupole mass spectrometer operating in multiple reaction monitoring. Characteristic fragment ions of S1P and related sphingolipids are monitored and subsequently analyzed relative to known standard concentrations of the pure compounds. Known problems of S1P quantification, such as carryover and insufficient HPLC separation, are discussed.
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Affiliation(s)
- Constantin Bode
- Molecular Cancer Research Centre, Charité University Medical School, Berlin, Germany
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Huang YL, Huang WP, Lee H. Roles of sphingosine 1-phosphate on tumorigenesis. World J Biol Chem 2011; 2:25-34. [PMID: 21537487 PMCID: PMC3083992 DOI: 10.4331/wjbc.v2.i2.25] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Revised: 02/10/2011] [Accepted: 02/16/2011] [Indexed: 02/05/2023] Open
Abstract
Sphingosine 1-phosphate (S1P) is a bioactive sphingolipid with a variety of biological activities. It is generated from the conversion of ceramide to sphingosine by ceramidase and the subsequent conversion of sphingosine to S1P, which is catalyzed by sphingosine kinases. Through increasing its intracellular levels by sphingolipid metabolism and binding to its cell surface receptors, S1P regulates several physiological and pathological processes, including cell proliferation, migration, angiogenesis and autophagy. These processes are responsible for tumor growth, metastasis and invasion and promote tumor survival. Since ceramide and S1P have distinct functions in regulating in cell fate decision, the balance between the ceramide/sphingosine/S1P rheostat becomes a potent therapeutic target for cancer cells. Herein, we summarize our current understanding of S1P signaling on tumorigenesis and its potential as a target for cancer therapy.
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Affiliation(s)
- Yuan-Li Huang
- Yuan-Li Huang, Department of Biotechnology, College of Health Science, Asia University, Taichung 41354, Taiwan, China
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Intracellular S1P generation is essential for S1P-induced motility of human lung endothelial cells: role of sphingosine kinase 1 and S1P lyase. PLoS One 2011; 6:e16571. [PMID: 21304987 PMCID: PMC3031585 DOI: 10.1371/journal.pone.0016571] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2010] [Accepted: 12/27/2010] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Earlier we have shown that extracellular sphingosine-1-phosphate (S1P) induces migration of human pulmonary artery endothelial cells (HPAECs) through the activation of S1P(1) receptor, PKCε, and PLD2-PKCζ-Rac1 signaling cascade. As endothelial cells generate intracellular S1P, here we have investigated the role of sphingosine kinases (SphKs) and S1P lyase (S1PL), that regulate intracellular S1P accumulation, in HPAEC motility. METHODOLOGY/PRINCIPAL FINDINGS Inhibition of SphK activity with a SphK inhibitor 2-(p-Hydroxyanilino)-4-(p-Chlorophenyl) Thiazole or down-regulation of Sphk1, but not SphK2, with siRNA decreased S1P(int), and attenuated S1P(ext) or serum-induced motility of HPAECs. On the contrary, inhibition of S1PL with 4-deoxypyridoxine or knockdown of S1PL with siRNA increased S1P(int) and potentiated motility of HPAECs to S1P(ext) or serum. S1P(ext) mediates cell motility through activation of Rac1 and IQGAP1 signal transduction in HPAECs. Silencing of SphK1 by siRNA attenuated Rac1 and IQGAP1 translocation to the cell periphery; however, knockdown of S1PL with siRNA or 4-deoxypyridoxine augmented activated Rac1 and stimulated Rac1 and IQGAP1 translocation to cell periphery. The increased cell motility mediated by down-regulation was S1PL was pertussis toxin sensitive suggesting "inside-out" signaling of intracellularly generated S1P. Although S1P did not accumulate significantly in media under basal or S1PL knockdown conditions, addition of sodium vanadate increased S1P levels in the medium and inside the cells most likely by blocking phosphatases including lipid phosphate phosphatases (LPPs). Furthermore, addition of anti-S1P mAb to the incubation medium blocked S1P(ext) or 4-deoxypyridoxine-dependent endothelial cell motility. CONCLUSIONS/SIGNIFICANCE These results suggest S1P(ext) mediated endothelial cell motility is dependent on intracellular S1P production, which is regulated, in part, by SphK1 and S1PL.
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Canals D, Jenkins RW, Roddy P, Hernández-Corbacho MJ, Obeid LM, Hannun YA. Differential effects of ceramide and sphingosine 1-phosphate on ERM phosphorylation: probing sphingolipid signaling at the outer plasma membrane. J Biol Chem 2010; 285:32476-85. [PMID: 20679347 DOI: 10.1074/jbc.m110.141028] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
ERM proteins are regulated by phosphorylation of the most C-terminal threonine residue, switching them from an activated to an inactivated form. However, little is known about the control of this regulation. Previous work in our group demonstrated that secretion of acid sphingomyelinase acts upstream of ERM dephosphorylation, suggesting the involvement of sphingomyelin (SM) hydrolysis in ERM regulation. To define the role of specific lipids, we employed recombinant bacterial sphingomyelinase (bSMase) as a direct probe of SM metabolism at the plasma membrane. bSMase induced a rapid dose- and time-dependent decrease in ERM dephosphorylation. ERM dephosphorylation was driven by ceramide generation and not by sphingomyelin depletion, as shown using recombinant sphingomyelinase D. The generation of ceramide at the plasma membrane was sufficient for ERM regulation, and no intracellular SM hydrolysis was required, as was visualized using Venus-tagged lysenin probe, which specifically binds SM. Interestingly, hydrolysis of plasma membrane bSMase-induced ceramide using bacterial ceramidase caused ERM hyperphosphorylation and formation of cell surface protrusions. The effects of plasma membrane ceramide hydrolysis were due to sphingosine 1-phosphate formation, as ERM phosphorylation was blocked by an inhibitor of sphingosine kinase and induced by sphingosine 1-phosphate. Taken together, these results demonstrate a new regulatory mechanism of ERM phosphorylation by sphingolipids with opposing actions of ceramide and sphingosine 1-phosphate. The approach also defines a tool kit to probe sphingolipid signaling at the plasma membrane.
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Affiliation(s)
- Daniel Canals
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina 29425, USA
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Serra M, Saba JD. Sphingosine 1-phosphate lyase, a key regulator of sphingosine 1-phosphate signaling and function. ACTA ACUST UNITED AC 2009; 50:349-62. [PMID: 19914275 DOI: 10.1016/j.advenzreg.2009.10.024] [Citation(s) in RCA: 142] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Montserrat Serra
- Children's Hospital Oakland Research Institute, 5700 Martin Luther King Jr. Way, Oakland, CA 94609-1673, USA
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