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Fukuzaki Y, Faustino J, Lecuyer M, Rayasam A, Vexler ZS. Global sphingosine-1-phosphate receptor 2 deficiency attenuates neuroinflammation and ischemic-reperfusion injury after neonatal stroke. iScience 2023; 26:106340. [PMID: 37009213 PMCID: PMC10064246 DOI: 10.1016/j.isci.2023.106340] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 10/31/2022] [Accepted: 03/01/2023] [Indexed: 03/07/2023] Open
Abstract
Arterial ischemic stroke is common in neonates-1 per 2,300-5,000 births-and therapeutic targets remain insufficiently defined. Sphingosine-1-phosphate receptor 2 (S1PR2), a major regulator of the CNS and immune systems, is injurious in adult stroke. Here, we assessed whether S1PR2 contributes to stroke induced by 3 h transient middle cerebral artery occlusion (tMCAO) in S1PR2 heterozygous (HET), knockout (KO), and wild type (WT) postnatal day 9 pups. HET and WT of both sexes displayed functional deficits in Open Field test whereas injured KO at 24 h reperfusion performed similarly to naives. S1PR2 deficiency protected neurons, attenuated infiltration of inflammatory monocytes, and altered vessel-microglia interactions without reducing increased cytokine levels in injured regions at 72 h. Pharmacologic inhibition of S1PR2 after tMCAO by JTE-013 attenuated injury 72 h after tMCAO. Importantly, the lack of S1PR2 alleviated anxiety and brain atrophy during chronic injury. Altogether, we identify S1PR2 as a potential new target for mitigating neonatal stroke.
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Affiliation(s)
- Yumi Fukuzaki
- Department of Neurology, University California San Francisco, Weill Institute for Neurosciences, San Francisco, CA 94158-0663, USA
| | - Joel Faustino
- Department of Neurology, University California San Francisco, Weill Institute for Neurosciences, San Francisco, CA 94158-0663, USA
| | - Matthieu Lecuyer
- Department of Neurology, University California San Francisco, Weill Institute for Neurosciences, San Francisco, CA 94158-0663, USA
| | - Aditya Rayasam
- Department of Neurology, University California San Francisco, Weill Institute for Neurosciences, San Francisco, CA 94158-0663, USA
| | - Zinaida S. Vexler
- Department of Neurology, University California San Francisco, Weill Institute for Neurosciences, San Francisco, CA 94158-0663, USA
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Zhu X, Wang X, Ying T, Li X, Tang Y, Wang Y, Yu T, Sun M, Zhao J, Du Y, Zhang L. Kaempferol alleviates the inflammatory response and stabilizes the pulmonary vascular endothelial barrier in LPS-induced sepsis through regulating the SphK1/S1P signaling pathway. Chem Biol Interact 2022; 368:110221. [DOI: 10.1016/j.cbi.2022.110221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 09/06/2022] [Accepted: 10/06/2022] [Indexed: 11/03/2022]
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MicroRNA-150 (miR-150) and Diabetic Retinopathy: Is miR-150 Only a Biomarker or Does It Contribute to Disease Progression? Int J Mol Sci 2022; 23:ijms232012099. [PMID: 36292956 PMCID: PMC9603433 DOI: 10.3390/ijms232012099] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 10/05/2022] [Accepted: 10/06/2022] [Indexed: 11/18/2022] Open
Abstract
Diabetic retinopathy (DR) is a chronic disease associated with diabetes mellitus and is a leading cause of visual impairment among the working population in the US. Clinically, DR has been diagnosed and treated as a vascular complication, but it adversely impacts both neural retina and retinal vasculature. Degeneration of retinal neurons and microvasculature manifests in the diabetic retina and early stages of DR. Retinal photoreceptors undergo apoptosis shortly after the onset of diabetes, which contributes to the retinal dysfunction and microvascular complications leading to vision impairment. Chronic inflammation is a hallmark of diabetes and a contributor to cell apoptosis, and retinal photoreceptors are a major source of intraocular inflammation that contributes to vascular abnormalities in diabetes. As the levels of microRNAs (miRs) are changed in the plasma and vitreous of diabetic patients, miRs have been suggested as biomarkers to determine the progression of diabetic ocular diseases, including DR. However, few miRs have been thoroughly investigated as contributors to the pathogenesis of DR. Among these miRs, miR-150 is downregulated in diabetic patients and is an endogenous suppressor of inflammation, apoptosis, and pathological angiogenesis. In this review, how miR-150 and its downstream targets contribute to diabetes-associated retinal degeneration and pathological angiogenesis in DR are discussed. Currently, there is no effective treatment to stop or reverse diabetes-caused neural and vascular degeneration in the retina. Understanding the molecular mechanism of the pathogenesis of DR may shed light for the future development of more effective treatments for DR and other diabetes-associated ocular diseases.
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Decreased MicroRNA-150 Exacerbates Neuronal Apoptosis in the Diabetic Retina. Biomedicines 2021; 9:biomedicines9091135. [PMID: 34572320 PMCID: PMC8469350 DOI: 10.3390/biomedicines9091135] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 08/27/2021] [Accepted: 08/30/2021] [Indexed: 12/27/2022] Open
Abstract
Diabetic retinopathy (DR) is a chronic complication associated with diabetes and the number one cause of blindness in working adults in the US. More than 90% of diabetic patients have obesity-associated type 2 diabetes (T2D), and 60% of T2D patients will develop DR. Photoreceptors undergo apoptosis shortly after the onset of diabetes, which contributes to the retinal dysfunction and microvascular complications leading to vision impairment. However, how diabetic insults cause photoreceptor apoptosis remains unclear. In this study, obesity-associated T2D mice and cultured photoreceptors were used to investigate how decreased microRNA-150 (miR-150) and its downstream target were involved in photoreceptor apoptosis. In the T2D retina, miR-150 was decreased with its target ETS-domain transcription factor (ELK1) and phosphorylated ELK1 at threonine 417 (pELK1T417) upregulated. In cultured photoreceptors, treatments with palmitic acid (PA), to mimic a high-fat environment, decreased miR-150 but upregulated ELK1, pELK1T417, and the translocation of pELK1T417 from the cytoplasm to the cell nucleus. Deletion of miR-150 (miR-150-/-) exacerbates T2D- or PA-induced photoreceptor apoptosis. Blocking the expression of ELK1 with small interfering RNA (siRNA) for Elk1 did not rescue PA-induced photoreceptor apoptosis. Translocation of pELK1T417 from cytoplasm-to-nucleus appears to be the key step of diabetic insult-elicited photoreceptor apoptosis.
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Cell fate determined by the activation balance between PKR and SPHK1. Cell Death Differ 2020; 28:401-418. [PMID: 32801355 PMCID: PMC7852545 DOI: 10.1038/s41418-020-00608-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 07/29/2020] [Accepted: 08/06/2020] [Indexed: 11/25/2022] Open
Abstract
Double-stranded RNA (dsRNA)-dependent protein kinase R (PKR) activation via autophosphorylation is the central cellular response to stress that promotes cell death or apoptosis. However, the key factors and mechanisms behind the simultaneous activation of pro-survival signaling pathways remain unknown. We have discovered a novel regulatory mechanism for the maintenance of cellular homeostasis that relies on the phosphorylation interplay between sphingosine kinase 1 (SPHK1) and PKR during exogenous stress. We identified SPHK1 as a previously unrecognized PKR substrate. Phosphorylated SPHK1, a central kinase, mediates the activation of PKR-induced pro-survival pathways by the S1P/S1PR1/MAPKs/IKKα signal axis, and antagonizes PKR-mediated endoplasmic reticulum (ER) stress signal transduction under stress conditions. Otherwise, phosphorylated SPHK1 also acts as the negative feedback factor, preferentially binding to the latent form of PKR at the C-terminal kinase motif, inhibiting the homodimerization of PKR, suppressing PKR autophosphorylation, and reducing the signaling strength for cell death and apoptosis. Our results suggest that the balance of the activation levels between PKR and SPHK1, a probable hallmark of homeostasis maintenance, determines cell fate during cellular stress response.
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Syed SN, Weigert A, Brüne B. Sphingosine Kinases are Involved in Macrophage NLRP3 Inflammasome Transcriptional Induction. Int J Mol Sci 2020; 21:ijms21134733. [PMID: 32630814 PMCID: PMC7370080 DOI: 10.3390/ijms21134733] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 06/26/2020] [Accepted: 06/30/2020] [Indexed: 12/20/2022] Open
Abstract
Recent studies suggested an important contribution of sphingosine-1-phospate (S1P) signaling via its specific receptors (S1PRs) in the production of pro-inflammatory mediators such as Interleukin (IL)-1β in cancer and inflammation. In an inflammation-driven cancer setting, we previously reported that myeloid S1PR1 signaling induces IL-1β production by enhancing NLRP3 (NOD-, LRR- and Pyrin Domain-Containing Protein 3) inflammasome activity. However, the autocrine role of S1P and enzymes acting on the S1P rheostat in myeloid cells are unknown. Using human and mouse macrophages with pharmacological or genetic intervention we explored the relative contribution of sphingosine kinases (SPHKs) in NLRP3 inflammasome activity regulation. We noticed redundancy in SPHK1 and SPHK2 activities towards macrophage NLRP3 inflammasome transcriptional induction and IL-1β secretion. However, pharmacological blockade of both kinases in unison completely abrogated NLRP3 inflammasome induction and IL-1β secretion. Interestingly, human and mouse macrophages demonstrate varied responses towards SPHKs inhibition and IL-1β secretion. Clinical datasets of renal cell carcinoma and psoriasis patients showed a positive correlation between enzymes affecting the S1P rheostat with NLRP3 inflammasome components expression, which corroborates our finding. Our data provide a better understanding on the role of SPHKs and de novo synthesized S1P in macrophage NLRP3 inflammasome activation.
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Affiliation(s)
- Shahzad Nawaz Syed
- Institute of Biochemistry I, Faculty of Medicine, Goethe-University Frankfurt, 60590 Frankfurt, Germany; (S.N.S.); (A.W.)
| | - Andreas Weigert
- Institute of Biochemistry I, Faculty of Medicine, Goethe-University Frankfurt, 60590 Frankfurt, Germany; (S.N.S.); (A.W.)
| | - Bernhard Brüne
- Institute of Biochemistry I, Faculty of Medicine, Goethe-University Frankfurt, 60590 Frankfurt, Germany; (S.N.S.); (A.W.)
- Project Group Translational Medicine and Pharmacology TMP, Fraunhofer Institute for Molecular Biology and Applied Ecology, 60596 Frankfurt, Germany
- German Cancer Consortium (DKTK), Partner Site Frankfurt, 60590 Frankfurt, Germany
- Frankfurt Cancer Institute, Goethe-University Frankfurt, 60596 Frankfurt, Germany
- Correspondence: ; Tel.: +49-69-6301-7424
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Bezgovsek J, Gulbins E, Friedrich SK, Lang KS, Duhan V. Sphingolipids in early viral replication and innate immune activation. Biol Chem 2018; 399:1115-1123. [DOI: 10.1515/hsz-2018-0181] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 06/21/2018] [Indexed: 01/08/2023]
Abstract
Abstract
In this review, we summarize the mechanisms by which sphingolipids modulate virus multiplication and the host innate immune response, using a number of host-virus systems as illustrative models. Sphingolipids exert diverse functions, both at the level of the viral life cycle and in the regulation of antiviral immune responses. Sphingolipids may influence viral replication in three ways: by serving as (co)receptors during viral entry, by modulating virus replication, and by shaping the antiviral immune response. Several studies have demonstrated that sphingosine kinases (SphK) and their product, sphingosine-1-phosphate (S1P), enhance the replication of influenza, measles, and hepatitis B virus (HBV). In contrast, ceramides, particularly S1P and SphK1, influence the expression of type I interferon (IFN-I) by modulating upstream antiviral signaling and enhancing dendritic cell maturation, differentiation, and positioning in tissue. The synthetic molecule α-galactosylceramide has also been shown to stimulate natural killer cell activation and interferon (IFN)-γ secretion. However, to date, clinical trials have failed to demonstrate any clinical benefit for sphingolipids in the treatment of cancer or HBV infection. Taken together, these findings show that sphingolipids play an important and underappreciated role in the control of virus replication and the innate immune response.
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Arish M, Husein A, Ali R, Tabrez S, Naz F, Ahmad MZ, Rub A. Sphingosine-1-phosphate signaling in Leishmania donovani infection in macrophages. PLoS Negl Trop Dis 2018; 12:e0006647. [PMID: 30118478 PMCID: PMC6118390 DOI: 10.1371/journal.pntd.0006647] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 08/31/2018] [Accepted: 06/28/2018] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Sphingosine-1-phosphate (S1P) is a crucial regulator of a wide array of cellular processes, such as apoptosis, cell proliferation, migration, and differentiation, but its role in Leishmania donovani infection is unknown. METHODOLOGY/ PRINCIPAL FINDINGS In the present study, we observed that L. donovani infection in THP-1 derived macrophages (TDM) leads to decrease in the expression of S1pr2 and S1pr3 at mRNA level. We further observed that Leishmania infection inhibits the phosphorylation of sphingosine kinase 1 (sphK1) in a time-dependent manner. Exogenous S1P supplementation decreases L. donovani induced ERK1/2 phosphorylation and increases p38 phosphorylation in TDM, resulting in a decrease in the intracellular parasite burden in a dose-dependent manner. On the other hand, sphK inhibition by DMS increases ERK1/2 phosphorylation leading to increased IL-10 and parasite load. To gain further insight, cytokines expression were checked in S1P supplemented TDM and we observed increase in IL-12, while decrease IL-10 expression at mRNA and protein levels. In addition, treatment of antagonist of S1PR2 and S1PR3 such as JTE-013 and CAY10444 respectively enhanced Leishmania-induced ERK1/2 phosphorylation and parasite load. CONCLUSIONS Our overall study not only reports the significant role of S1P signaling during L. donovani infection but also provides a novel platform for the development of new drugs against Leishmaniasis.
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Affiliation(s)
- Mohd Arish
- Infection and Immunity Lab (414), Department of Biotechnology, Jamia Millia Islamia (A Central University), New Delhi, India
| | - Atahar Husein
- Infection and Immunity Lab (414), Department of Biotechnology, Jamia Millia Islamia (A Central University), New Delhi, India
| | - Rahat Ali
- Infection and Immunity Lab (414), Department of Biotechnology, Jamia Millia Islamia (A Central University), New Delhi, India
| | - Shams Tabrez
- Infection and Immunity Lab (414), Department of Biotechnology, Jamia Millia Islamia (A Central University), New Delhi, India
| | - Farha Naz
- Centre for Interdisciplinary Research in Basic Science, Jamia Millia Islamia (A Central University), New Delhi, India
| | - Mohammad Zulfazal Ahmad
- Infection and Immunity Lab (414), Department of Biotechnology, Jamia Millia Islamia (A Central University), New Delhi, India
| | - Abdur Rub
- Infection and Immunity Lab (414), Department of Biotechnology, Jamia Millia Islamia (A Central University), New Delhi, India
- Department of Medical Laboratory Science, College of Applied Medical Sciences, Majmaah University, Al Majmaah, Saudi Arabia
- * E-mail: , ,
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SPHK-2 Promotes the Particle-Induced Inflammation of RAW264.7 by Maintaining Consistent Expression of TNF-α and IL-6. Inflammation 2018; 41:1498-1507. [DOI: 10.1007/s10753-018-0795-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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10
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Sun W, Ding Z, Xu S, Su Z, Li H. Crosstalk between TLR2 and Sphk1 in microglia in the cerebral ischemia/reperfusion-induced inflammatory response. Int J Mol Med 2017; 40:1750-1758. [PMID: 29039449 PMCID: PMC5716455 DOI: 10.3892/ijmm.2017.3165] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 09/06/2017] [Indexed: 01/06/2023] Open
Abstract
Stroke is associated with high morbidity and mortality, and much remains unknown about the injury-related mechanisms that occur following reperfusion. This study aimed to explore the roles of Toll-like receptor 2 (TLR2) and sphingosine kinase 1 (Sphk1) in microglial cells in inflammatory responses induced by cerebral ischemia/reperfusion (I/R). For this purpose, C57BL/6 mice were randomly divided into 4 groups as follows: the sham-operated group, the I/R group, the I/R group treated with TLR2 antibody, and the I/R group treated with N,N-dimethylsphingosine. Focal cerebral I/R was induced by middle cerebral artery occlusion. Double-labeling immunofluorescence was used to observe the protein expression of TLR2 and Sphk1 in the ischemic brain tissue. Quantitative polymerase chain reaction was performed to determine the mRNA levels of TLR2 and Sphkl in ischemic brain tissue. Enzyme-linked immunosorbent assay was carried out to detect the protein contents of interleukin (IL)-1β, tumor necrosis factor-α (TNF-α), IL-17 and IL-23 in ischemic brain tissue. The results revealed that I/R upregulated TLR2 and Sphk1 expression in microglial cells, and the inhibition of either TLR2 or Sphk1 inhibited the expression of the pro-inflammatory cytokines, IL-1β, TNF-α, IL-17 and IL-23. Notably, the inhibition of TLR2 activity also decreased Sphk1 expression. These results thus indicate that the activation of microglial cells, via a TLR2→Sphk1→pro-inflammatory cytokine (IL-1β, TNF-α, IL-17 and IL-23) pathway, may participate in I/R injury.
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Affiliation(s)
- Wei Sun
- Department of Neurology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China
| | - Zhaoming Ding
- Department of Thyroid Surgery, The Third Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China
| | - Shengjie Xu
- Department of Pathology, Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China
| | - Zhiqiang Su
- Department of Neurology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China
| | - Hulun Li
- Department of Neurobiology, Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China
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Gabriel TL, Mirzaian M, Hooibrink B, Ottenhoff R, van Roomen C, Aerts JMFG, van Eijk M. Induction of Sphk1 activity in obese adipose tissue macrophages promotes survival. PLoS One 2017; 12:e0182075. [PMID: 28753653 PMCID: PMC5533446 DOI: 10.1371/journal.pone.0182075] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 07/12/2017] [Indexed: 02/07/2023] Open
Abstract
During obesity, adipose tissue macrophages (ATM) are increased in concert with local inflammation and insulin resistance. Since the levels of sphingolipid (SLs) in adipose tissue (AT) are altered during obesity we investigated the potential impact of SLs on ATMs. For this, we first analyzed expression of SL metabolizing genes in ATMs isolated from obese mice. A marked induction of sphingosine kinase 1 (Sphk1) expression was observed in obese ATM when compared to lean ATM. This induction was observed in both MGL-ve (M1) and MGL1+ve (M2) macrophages from obese WAT. Next, RAW264.7 cells were exposed to excessive palmitate, resulting in a similar induction of Sphk1. This Sphk1 induction was also observed when cells were treated with chloroquine, a lysosomotropic amine impacting lysosome function. Simultaneous incubation of RAW cells with palmitate and the Sphk1 inhibitor SK1-I promoted cell death, suggesting a protective role of Sphk1 during lipotoxic conditions. Interestingly, a reduction of endoplasmic reticulum (ER) stress related genes was detected in obese ATM and was found to be associated with elevated Sphk1 expression. Altogether, our data suggest that lipid overload in ATM induces Sphk1, which promotes cell viability.
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Affiliation(s)
- Tanit L. Gabriel
- Department of Medical Biochemistry, Academic Medical Center, Amsterdam, The Netherlands
| | - Mina Mirzaian
- Department of Biochemistry, Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands
| | - Berend Hooibrink
- Department of Cell Biology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Roelof Ottenhoff
- Department of Medical Biochemistry, Academic Medical Center, Amsterdam, The Netherlands
| | - Cindy van Roomen
- Department of Medical Biochemistry, Academic Medical Center, Amsterdam, The Netherlands
| | - Johannes M. F. G. Aerts
- Department of Biochemistry, Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands
| | - Marco van Eijk
- Department of Medical Biochemistry, Academic Medical Center, Amsterdam, The Netherlands
- Department of Biochemistry, Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands
- * E-mail:
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Hsieh LTH, Nastase MV, Roedig H, Zeng-Brouwers J, Poluzzi C, Schwalm S, Fork C, Tredup C, Brandes RP, Wygrecka M, Huwiler A, Pfeilschifter J, Schaefer L. Biglycan- and Sphingosine Kinase-1 Signaling Crosstalk Regulates the Synthesis of Macrophage Chemoattractants. Int J Mol Sci 2017; 18:ijms18030595. [PMID: 28282921 PMCID: PMC5372611 DOI: 10.3390/ijms18030595] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 02/27/2017] [Accepted: 03/06/2017] [Indexed: 12/14/2022] Open
Abstract
In its soluble form, the extracellular matrix proteoglycan biglycan triggers the synthesis of the macrophage chemoattractants, chemokine (C-C motif) ligand CCL2 and CCL5 through selective utilization of Toll-like receptors (TLRs) and their adaptor molecules. However, the respective downstream signaling events resulting in biglycan-induced CCL2 and CCL5 production have not yet been defined. Here, we show that biglycan stimulates the production and activation of sphingosine kinase 1 (SphK1) in a TLR4- and Toll/interleukin (IL)-1R domain-containing adaptor inducing interferon (IFN)-β (TRIF)-dependent manner in murine primary macrophages. We provide genetic and pharmacological proof that SphK1 is a crucial downstream mediator of biglycan-triggered CCL2 and CCL5 mRNA and protein expression. This is selectively driven by biglycan/SphK1-dependent phosphorylation of the nuclear factor NF-κB p65 subunit, extracellular signal-regulated kinase (Erk)1/2 and p38 mitogen-activated protein kinases. Importantly, in vivo overexpression of soluble biglycan causes Sphk1-dependent enhancement of renal CCL2 and CCL5 and macrophage recruitment into the kidney. Our findings describe the crosstalk between biglycan- and SphK1-driven extracellular matrix- and lipid-signaling. Thus, SphK1 may represent a new target for therapeutic intervention in biglycan-evoked inflammatory conditions.
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Affiliation(s)
- Louise Tzung-Harn Hsieh
- Pharmazentrum Frankfurt, Institut für Allgemeine Pharmakologie und Toxikologie, Klinikum der Goethe Universität, Theodor-Stern-Kai 7, Frankfurt am Main 60590, Germany.
| | - Madalina-Viviana Nastase
- Pharmazentrum Frankfurt, Institut für Allgemeine Pharmakologie und Toxikologie, Klinikum der Goethe Universität, Theodor-Stern-Kai 7, Frankfurt am Main 60590, Germany.
- National Institute for Chemical-Pharmaceutical Research and Development, 112 Vitan Avenue, Bucharest 031299, Romania.
| | - Heiko Roedig
- Pharmazentrum Frankfurt, Institut für Allgemeine Pharmakologie und Toxikologie, Klinikum der Goethe Universität, Theodor-Stern-Kai 7, Frankfurt am Main 60590, Germany.
| | - Jinyang Zeng-Brouwers
- Pharmazentrum Frankfurt, Institut für Allgemeine Pharmakologie und Toxikologie, Klinikum der Goethe Universität, Theodor-Stern-Kai 7, Frankfurt am Main 60590, Germany.
| | - Chiara Poluzzi
- Pharmazentrum Frankfurt, Institut für Allgemeine Pharmakologie und Toxikologie, Klinikum der Goethe Universität, Theodor-Stern-Kai 7, Frankfurt am Main 60590, Germany.
| | - Stephanie Schwalm
- Pharmazentrum Frankfurt, Institut für Allgemeine Pharmakologie und Toxikologie, Klinikum der Goethe Universität, Theodor-Stern-Kai 7, Frankfurt am Main 60590, Germany.
| | - Christian Fork
- Institut für Kardiovaskulare Physiologie, Klinikum der Goethe-Universität, Theodor-Stern-Kai 7, Frankfurt am Main 60590, Germany.
| | - Claudia Tredup
- Pharmazentrum Frankfurt, Institut für Allgemeine Pharmakologie und Toxikologie, Klinikum der Goethe Universität, Theodor-Stern-Kai 7, Frankfurt am Main 60590, Germany.
| | - Ralf P Brandes
- Institut für Kardiovaskulare Physiologie, Klinikum der Goethe-Universität, Theodor-Stern-Kai 7, Frankfurt am Main 60590, Germany.
| | - Malgorzata Wygrecka
- Department of Biochemistry, Faculty of Medicine, Universities of Giessen and Marburg Lung Center, Friedrichstrasse 24, Giessen 35392, Germany.
| | - Andrea Huwiler
- Institute of Pharmacology, University of Bern, Inselspital INO-F, Bern CH-3010, Switzerland.
| | - Josef Pfeilschifter
- Pharmazentrum Frankfurt, Institut für Allgemeine Pharmakologie und Toxikologie, Klinikum der Goethe Universität, Theodor-Stern-Kai 7, Frankfurt am Main 60590, Germany.
| | - Liliana Schaefer
- Pharmazentrum Frankfurt, Institut für Allgemeine Pharmakologie und Toxikologie, Klinikum der Goethe Universität, Theodor-Stern-Kai 7, Frankfurt am Main 60590, Germany.
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Sphingosine kinase 1 is a reliable prognostic factor and a novel therapeutic target for uterine cervical cancer. Oncotarget 2016; 6:26746-56. [PMID: 26311741 PMCID: PMC4694949 DOI: 10.18632/oncotarget.4818] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 07/11/2015] [Indexed: 01/03/2023] Open
Abstract
Sphingosine kinase 1 (SPHK1), an oncogenic kinase, has previously been found to be upregulated in various types of human malignancy and to play a crucial role in tumor development and progression. Although SPHK1 has gained increasing prominence as an important enzyme in cancer biology, its potential as a predictive biomarker and a therapeutic target in cervical cancer remains unknown. SPHK1 expression was examined in 287 formalin-fixed, paraffin-embedded cervical cancer tissues using immunohistochemistry, and its clinical implications and prognostic significance were analyzed. Cervical cancer cell lines including HeLa and SiHa were treated with the SPHK inhibitors SKI-II or FTY720, and effects on cell survival, apoptosis, angiogenesis, and invasion were examined. Moreover, the effects of FTY720 on tumor growth were evaluated using a patient-derived xenograft (PDX) model of cervical cancer. Immunohistochemical analysis revealed that expression of SPHK1 was significantly increased in cervical cancer compared with normal tissues. SPHK1 expression was significantly associated with tumor size, invasion depth, FIGO stage, lymph node metastasis, and lymphovascular invasion. Patients with high SPHK1 expression had lower overall survival and recurrence-free survival rates than those with low expression. Treatment with SPHK inhibitors significantly reduced viability and increased apoptosis in cervical cancer cells. Furthermore, FTY720 significantly decreased in vivo tumor weight in the PDX model of cervical cancer. We provide the first convincing evidence that SPHK1 is involved in tumor development and progression of cervical cancer. Our data suggest that SPHK1 might be a potential prognostic marker and therapeutic target for the treatment of cervical cancer.
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Jones ZB, Ren Y. Sphingolipids in spinal cord injury. INTERNATIONAL JOURNAL OF PHYSIOLOGY, PATHOPHYSIOLOGY AND PHARMACOLOGY 2016; 8:52-69. [PMID: 27570580 PMCID: PMC4981650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 07/19/2016] [Indexed: 06/06/2023]
Abstract
Spinal cord injury (SCI) is a debilitating condition that affects millions of individuals worldwide. Despite progress over the last few decades, the molecular mechanisms of secondary SCI that continue to occur days and weeks after the original trauma remain poorly understood. As a result, current therapies for SCI are only marginally effective. Sphingolipids, a diverse class of bioactive lipids, have been shown to regulate SCI repair and key secondary injury processes such as apoptosis, ischemia and inflammation. This review will discuss the numerous roles of sphingolipids and highlight the potential of sphingolipid-targeted therapies for SCI.
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Affiliation(s)
- Zachary B Jones
- Department of Biomedical Sciences, Florida State UniversityTallahassee, FL, USA
| | - Yi Ren
- Department of Biomedical Sciences, Florida State UniversityTallahassee, FL, USA
- Institute of Inflammation and Diseases, The First Affiliated Hospital of Wenzhou Medical UniversityWenzhou, China
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Tian T, Zhao Y, Huang Q, Li J. n-3 Polyunsaturated Fatty Acids Improve Inflammation via Inhibiting Sphingosine Kinase 1 in a Rat Model of Parenteral Nutrition and CLP-Induced Sepsis. Lipids 2016; 51:271-8. [PMID: 26856322 DOI: 10.1007/s11745-016-4129-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 01/21/2016] [Indexed: 12/31/2022]
Abstract
The sphingosine kinase 1 (SphK1)/sphingosine-1-phosphate (S1P) pathway plays a key role in inflammation. Parenteral nutrition containing n-3 polyunsaturated fatty acids (n-3 PUFA) may regulate inflammatory reactions. The aim of this study is to determine whether n-3 PUFA may improve inflammatory responses by neutralizing SphK1 signaling. Rat models of parenteral nutrition, cecal ligation and puncture (CLP)-induced sepsis were generated. Male Sprague-Dawley rats were operated for CLP on day 2 after venous catheterization. The rats were randomized to receive normal saline (NS; n = 20), parenteral nutrition (PN; n = 20), or PN + fish oil (FO; n = 20) for 5 days. The daily intake of fish oil (1.25-2.82 g EPA and 1.44-3.09 g DHA per 100 ml) in the FO group was approximately 1.8 g/kg body weight/day. Rats in the control group (n = 10) were subjected to sham operation and received a chow diet. Spleen tissues were collected for SphK1 and S1P receptor expression analysis. Our data showed that n-3 PUFA ameliorated the survival rate. SphK1 expression and its enzymatic activity were significantly upregulated in sepsis rats. Furthermore, mRNA and protein levels of S1PR3, but not S1PR1, were also facilitated after CLP. However, PN + FO dramatically decreased SphK1 mRNA level and its enzymatic activity. S1PR3 expression was also attenuated by FO addition. In conclusion, the anti-inflammatory effect of n-3 PUFA may be linked to the inhibition of the SphK1/S1P pathway in a rat model of parenteral nutrition and CLP-induced sepsis.
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Affiliation(s)
- Tao Tian
- Department of Surgery, Jinling Hospital, Medical School of Nanjing University, 305 East Zhongshan Road, Nanjing, 210002, Jiangsu, China
| | - Yunzhao Zhao
- Department of Surgery, Jinling Hospital, Medical School of Nanjing University, 305 East Zhongshan Road, Nanjing, 210002, Jiangsu, China.
| | - Qian Huang
- Department of Surgery, Jinling Hospital, Medical School of Nanjing University, 305 East Zhongshan Road, Nanjing, 210002, Jiangsu, China
| | - Jieshou Li
- Department of Surgery, Jinling Hospital, Medical School of Nanjing University, 305 East Zhongshan Road, Nanjing, 210002, Jiangsu, China
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16
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Vettorazzi S, Bode C, Dejager L, Frappart L, Shelest E, Klaßen C, Tasdogan A, Reichardt HM, Libert C, Schneider M, Weih F, Henriette Uhlenhaut N, David JP, Gräler M, Kleiman A, Tuckermann JP. Glucocorticoids limit acute lung inflammation in concert with inflammatory stimuli by induction of SphK1. Nat Commun 2015; 6:7796. [PMID: 26183376 PMCID: PMC4518295 DOI: 10.1038/ncomms8796] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 06/11/2015] [Indexed: 12/18/2022] Open
Abstract
Acute lung injury (ALI) is a severe inflammatory disease for which no specific treatment exists. As glucocorticoids have potent immunosuppressive effects, their application in ALI is currently being tested in clinical trials. However, the benefits of this type of regimen remain unclear. Here we identify a mechanism of glucocorticoid action that challenges the long-standing dogma of cytokine repression by the glucocorticoid receptor. Contrarily, synergistic gene induction of sphingosine kinase 1 (SphK1) by glucocorticoids and pro-inflammatory stimuli via the glucocorticoid receptor in macrophages increases circulating sphingosine 1-phosphate levels, which proves essential for the inhibition of inflammation. Chemical or genetic inhibition of SphK1 abrogates the therapeutic effects of glucocorticoids. Inflammatory p38 MAPK- and mitogen- and stress-activated protein kinase 1 (MSK1)-dependent pathways cooperate with glucocorticoids to upregulate SphK1 expression. Our findings support a critical role for SphK1 induction in the suppression of lung inflammation by glucocorticoids, and therefore provide rationales for effective anti-inflammatory therapies. Endothelial damage is a major component of acute lung injury pathogenesis. Here the authors show that in a mouse model of acute lung injury, glucocorticoids induce sphingosine kinase 1 production in macrophages, promoting endothelial barrier function and ameliorating the disease.
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Affiliation(s)
- Sabine Vettorazzi
- Institute of Comparative Molecular Endocrinology (CME), Ulm University, 89081 Ulm, Germany.,Leibniz Institute for Age Research - Fritz Lipmann Institute, 07745 Jena, Germany
| | - Constantin Bode
- Molecular Cancer Research Centre (MKFZ), Charité - University Medical School (CVK), 13353 Berlin, Germany
| | - Lien Dejager
- Inflammation Research Center, Mouse Genetics in Inflammation group, VIB and University Ghent, B9052 Ghent, Belgium
| | - Lucien Frappart
- Department of Pathology, Bat 10, HCL-Edouard Herriot Hospital, INSERM U590, 69437 Lyon, France
| | - Ekaterina Shelest
- Leibniz Institute for Natural Product Research and Infection Biology Hans Knöll Institute (HKI), 07745 Jena, Germany
| | - Carina Klaßen
- Institute for Cellular and Molecular Immunology, University of Göttingen Medical School, 37073 Göttingen, Germany
| | | | - Holger M Reichardt
- Institute for Cellular and Molecular Immunology, University of Göttingen Medical School, 37073 Göttingen, Germany
| | - Claude Libert
- Inflammation Research Center, Mouse Genetics in Inflammation group, VIB and University Ghent, B9052 Ghent, Belgium
| | - Marion Schneider
- Section of Experimental Anesthesiology, University Clinic Ulm, 89081 Ulm, Germany
| | - Falk Weih
- Leibniz Institute for Age Research - Fritz Lipmann Institute, 07745 Jena, Germany
| | - N Henriette Uhlenhaut
- Institute for Diabetes and Obesity, Helmholtz Zentrum München, 85748 Garching, Germany
| | - Jean-Pierre David
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Markus Gräler
- Molecular Cancer Research Centre (MKFZ), Charité - University Medical School (CVK), 13353 Berlin, Germany.,Department of Anesthesiology and Intensive Care Medicine, Center for Sepsis Control and Care (CSCC) and Center for Molecular Biomedicine (CMB), University Hospital Jena, 07740 Jena, Germany
| | - Anna Kleiman
- Leibniz Institute for Age Research - Fritz Lipmann Institute, 07745 Jena, Germany.,Department of Anesthesiology and Intensive Care Medicine, Center for Sepsis Control and Care (CSCC) and Center for Molecular Biomedicine (CMB), University Hospital Jena, 07740 Jena, Germany
| | - Jan P Tuckermann
- Institute of Comparative Molecular Endocrinology (CME), Ulm University, 89081 Ulm, Germany.,Leibniz Institute for Age Research - Fritz Lipmann Institute, 07745 Jena, Germany
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17
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Sphingosin-1-phosphate Receptor 1: a Potential Target to Inhibit Neuroinflammation and Restore the Sphingosin-1-phosphate Metabolism. Can J Neurol Sci 2015; 42:195-202. [PMID: 25860537 DOI: 10.1017/cjn.2015.19] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Recent evidence suggests that an extreme shift may occur in sphingosine metabolism in neuroinflammatory contexts. Sphingosine 1-phosphate (S1P)-metabolizing enzymes (SMEs) regulate the level of S1P. We recently found that FTY720, a S1P analogue, and SEW2871, a selective S1P receptor 1 (S1P1) agonist, provide protection against neural damage and memory deficit in amyloid beta (Aβ)-injected animals. This study aimed to evaluate the effects of these two analogues on the expression of SMEs as well as their anti-inflammatory roles. METHODS Rats were treated with intracerebral lipopolysaccharide (LPS) or Aβ. Memory impairment was assessed by Morris water maze and the effects of drugs on SMEs as well as inflammatory markers, TNF- α and COX-II, were determined by immunoblotting. RESULTS Aβ and LPS differentially altered the expression profile of SMEs. In Aβ-injected animals, FTY720 and SEW2871 treatments exerted anti-inflammatory effects and restored the expression profile of SMEs, in parallel to our previous findings. In LPS animals however, in spite of anti-inflammatory effects of the two analogues, only FTY720 restored the levels of SMEs and prevented memory deficit. CONCLUSION The observed ameliorating effects of FTY720 and SEW7821 can be partly attributed to the interruption of the vicious cycle of abnormal S1P metabolism and neuro-inflammation. The close imitation of the FTY720 effects by SW2871 in Aβ-induced neuro-inflammation may highlight the attractive role of S1P1 as a potential target to restore S1P metabolism and inhibit inflammatory processes.
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18
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Burow P, Klapperstück M, Markwardt F. Activation of ATP secretion via volume-regulated anion channels by sphingosine-1-phosphate in RAW macrophages. Pflugers Arch 2014; 467:1215-26. [PMID: 24965069 DOI: 10.1007/s00424-014-1561-8] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Accepted: 06/17/2014] [Indexed: 12/13/2022]
Abstract
We report the activation of outwardly rectifying anion currents by sphingosine-1-phosphate (S1P) in the murine macrophage cell line RAW 264.7. The S1P-induced current is mainly carried by anions, because the reversal potential of the current was shifted by replacement of extracellular Cl(-) by glutamate(-) but not when extracellular Na(+) was substituted by Tris(+). The inhibition of the current by hypertonic extracellular or hypotonic intracellular solution as well as the inhibitory effects of NPPB, tamoxifen, and glibenclamide indicates that the anion current is mediated by volume-regulated anion channels (VRAC). The S1P effect was blocked by intracellular GDPβS and W123, which points to signaling via the S1P receptor 1 (S1PR1) and G proteins. As cytochalasin D diminished the action of S1P, we conclude that the actin cytoskeleton is involved in the stimulation of VRAC. S1P and hypotonic extracellular solution induced secretion of ATP from the macrophages, which in both cases was blocked in a similar way by typical VRAC blockers. We suppose that the S1P-induced ATP secretion in macrophages via activation of VRAC constitutes a functional link between sphingolipid and purinergic signaling in essential processes such as inflammation and migration of leukocytes as well as phagocytosis and the killing of intracellular bacteria.
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Affiliation(s)
- Philipp Burow
- Julius Bernstein Institute for Physiology, Martin Luther University Halle, Magdeburger Str. 6, 06097, Halle/Saale, Germany
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19
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Pyne NJ, Ohotski J, Bittman R, Pyne S. The role of sphingosine 1-phosphate in inflammation and cancer. Adv Biol Regul 2014; 54:121-129. [PMID: 24070975 DOI: 10.1016/j.jbior.2013.08.005] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Revised: 08/31/2013] [Accepted: 08/31/2013] [Indexed: 06/02/2023]
Abstract
The enzymes that catalyze formation of the bioactive sphingolipid, sphingosine 1-phosphate, sphingosine kinase 1 and 2, are predictive markers in inflammatory diseases and cancer as evidenced by data from patients, knockout mice and the use of available molecular and chemical inhibitors. Thus, there is a compelling case for therapeutic targeting of sphingosine kinase. In addition, there are several examples of functional interaction between sphingosine 1-phosphate receptors and sphingosine kinase 1 that can drive malicious amplification loops that promote cancer cell growth. These novel aspects of sphingosine 1-phosphate pathobiology are reviewed herein.
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Affiliation(s)
- Nigel J Pyne
- Cell Biology Research Group, Strathclyde Institute of Pharmacy and Biomedical Science, University of Strathclyde, 161 Cathedral Street, Glasgow G4 0RE, UK.
| | - Jan Ohotski
- Cell Biology Research Group, Strathclyde Institute of Pharmacy and Biomedical Science, University of Strathclyde, 161 Cathedral Street, Glasgow G4 0RE, UK
| | - Robert Bittman
- Department of Chemistry and Biochemistry, Queens College of the City University of New York, Flushing, New York 11367-1597, USA
| | - Susan Pyne
- Cell Biology Research Group, Strathclyde Institute of Pharmacy and Biomedical Science, University of Strathclyde, 161 Cathedral Street, Glasgow G4 0RE, UK
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20
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Quint P, Ruan M, Pederson L, Kassem M, Westendorf JJ, Khosla S, Oursler MJ. Sphingosine 1-phosphate (S1P) receptors 1 and 2 coordinately induce mesenchymal cell migration through S1P activation of complementary kinase pathways. J Biol Chem 2013; 288:5398-406. [PMID: 23300082 DOI: 10.1074/jbc.m112.413583] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Normal bone turnover requires tight coupling of bone resorption and bone formation to preserve bone quantity and structure. With aging and during several pathological conditions, this coupling breaks down, leading to either net bone loss or excess bone formation. To preserve or restore normal bone metabolism, it is crucial to determine the mechanisms by which osteoclasts and osteoblast precursors interact and contribute to coupling. We showed that osteoclasts produce the chemokine sphingosine 1-phosphate (S1P), which stimulates osteoblast migration. Thus, osteoclast-derived S1P may recruit osteoblasts to sites of bone resorption as an initial step in replacing lost bone. In this study we investigated the mechanisms by which S1P stimulates mesenchymal (skeletal) cell chemotaxis. S1P treatment of mesenchymal (skeletal) cells activated RhoA GTPase, but this small G protein did not contribute to migration. Rather, two S1P receptors, S1PR1 and S1PR2, coordinately promoted migration through activation of the JAK/STAT3 and FAK/PI3K/AKT signaling pathways, respectively. These data demonstrate that the chemokine S1P couples bone formation to bone resorption through activation of kinase signaling pathways.
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Affiliation(s)
- Patrick Quint
- Endocrine Research Unit and Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, Minnesota 55905, USA.
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21
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Chong W, Li Y, Liu B, Zhao T, Fukudome EY, Liu Z, Smith WM, Velmahos GC, deMoya MA, Alam HB. Histone deacetylase inhibitor suberoylanilide hydroxamic acid attenuates Toll-like receptor 4 signaling in lipopolysaccharide-stimulated mouse macrophages. J Surg Res 2012; 178:851-9. [PMID: 22868051 DOI: 10.1016/j.jss.2012.07.023] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2012] [Revised: 07/03/2012] [Accepted: 07/09/2012] [Indexed: 01/22/2023]
Abstract
OBJECTIVE We have previously demonstrated that pretreatment and posttreatment of animals with suberoylanilide hydroxamic acid (SAHA), a histone deacetylase inhibitor, can improve survival in a mouse model of lipopolysaccharide (LPS)-induced severe shock. This study was designed to assess whether SAHA affects LPS/Toll-like receptor 4 signaling through acetylation of heat shock protein 90 (HSP90) and degradation of its client protein interleukin-1 receptor-associated kinase 1 (IRAK1). METHODS RAW264.7 cells were exposed to LPS (1 μg/mL) for 2 h, followed by treatment with SAHA (10 μM) or geldanamycin (3 μM), an inhibitor of HSP90. Sham (no SAHA, no LPS) macrophages served as a control. The cells were harvested at different time points, and time zero served as the reference point. RESULTS LPS dramatically increased protein expression of myeloid differentiation factor 88 and IRAK1, and stimulated nuclear translocation of nuclear factor κB, leading to an increases of gene expression and protein production of tumor necrosis factor α and interleukin-6. Treatment with SAHA significantly attenuated these LPS-stimulated alterations. LPS or SAHA did not change the levels of HSP90 protein, but immunoprecipitation studies demonstrated that SAHA treatment enhanced acetylation of HSP90, and increased the dissociation of IRAK1, compared to the LPS control. CONCLUSIONS SAHA suppresses LPS/Toll-like receptor 4 signaling in LPS-stimulated macrophages through multiple potential mechanisms. It inhibits the function of HSP90 through hyperacetylation of the chaperone protein, which results in dissociation and degradation of the client protein IRAK1 and, at least in part, leads to a decrease in nuclear translocation of nuclear factor κB and attenuation of key proinflammatory cytokine expression.
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Affiliation(s)
- Wei Chong
- Department of Surgery, Division of Trauma, Emergency Surgery and Surgical Critical Care, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA
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22
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Abstract
OBJECTIVE To investigate the role of sphingosine kinase 1 (SphK1)/sphingosine 1-phosphate (S1P) signaling in inflammatory response in severe acute pancreatitis (SAP). BACKGROUND SAP is an acute inflammatory process of the pancreas, which may lead to systemic inflammatory response syndrome and multiorgan dysfunction syndrome. SphK1 and its product S1P have been implicated in inflammatory response and various immune cell functions. However, the potential role for SphK1/S1P in inflammatory response in SAP is still unclear. METHODS Twenty-two patients with SAP were enrolled in this study. SphK1 expression on peripheral neutrophils, monocytes, and lymphocytes was evaluated by flow cytometry. SphK enzymatic activity in neutrophils and lymphocytes was measured using a radiometric assay. The expression of S1P1 and S1P3 mRNA was determined by reverse transcriptase-polymerase chain reaction (RT-PCR). The serum levels of tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1β), and IL-6 were measured by ELISA. RESULTS The expression of SphK1 and SphK activity were markedly increased in peripheral immune cells in the early stage of SAP and then reduced in the restoration stage in the patients. Moreover, we found that the level of S1P3 mRNA in peripheral neutrophils and lymphocytes of SAP patients was significantly elevated in the early stage as compared with the healthy volunteers, and it reduced in the restoration period. SphK1 expression on human peripheral neutrophils, monocytes, and CD4(+) T lymphocytes were positively correlated with the APACHE (Acute Physiological and Chronic Health Evaluation) II scores in patients with SAP. The levels of serum proinflammatory cytokines including TNF-α, IL-1β, and IL-6 showed similar shifts with intracellular SphK1 expression in SAP patients. CONCLUSIONS The authors identified a link between the SphK1 expression on peripheral immune cells and the severity of SAP. Observations showed a possible immunomodulating role for SphK1/S1P signaling in inflammatory response in SAP, suggesting that regulation of SphK1/S1P pathway may represent novel targets in the treatment of SAP.
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23
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Grin’kina NM, Karnabi EE, Damania D, Wadgaonkar S, Muslimov IA, Wadgaonkar R. Sphingosine kinase 1 deficiency exacerbates LPS-induced neuroinflammation. PLoS One 2012; 7:e36475. [PMID: 22615770 PMCID: PMC3355156 DOI: 10.1371/journal.pone.0036475] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Accepted: 04/09/2012] [Indexed: 11/24/2022] Open
Abstract
The pathogenesis of inflammation in the central nervous system (CNS), which contributes to numerous neurodegenerative diseases and results in encephalopathy and neuroinflammation, is poorly understood. Sphingolipid metabolism plays a crucial role in maintaining cellular processes in the CNS, and thus mediates the various pathological consequences of inflammation. For a better understanding of the role of sphingosine kinase activation during neuroinflammation, we developed a bacterial lipopolysaccharide (LPS)-induced brain injury model. The onset of the inflammatory response was observed beginning 4 hours after intracerebral injection of LPS into the lateral ventricles of the brain. A comparison of established neuroinflammatory parameters such as white matter rarefactions, development of cytotoxic edema, astrogliosis, loss of oligodendrocytes, and major cytokines levels in wild type and knockout mice suggested that the neuroinflammatory response in SphK1-/- mice was significantly upregulated. At 6 hours after intracerebroventricular injection of LPS in SphK1-/- mice, the immunoreactivity of the microglia markers and astrocyte marker glial fibrillary acidic protein (GFAP) were significantly increased, while the oligodendrocyte marker O4 was decreased compared to WT mice. Furthermore, western blotting data showed increased levels of GFAP. These results suggest that SphK1 activation is involved in the regulation of LPS induced brain injury. RESEARCH HIGHLIGHTS: • Lipopolysaccharide (LPS) intracerebral injection induces severe neuroinflammation. • Sphingosine kinase 1 deletion worsens the effect of the LPS. • Overexpression of SphK1 might be a potential new treatment approach to neuroinflammation.
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Affiliation(s)
- Natalia M. Grin’kina
- SUNY Downstate Medical Center, Brooklyn, New York, United States of America
- Department of Research and Development VA Medical Center, Brooklyn, New York, United States of America
| | - Eddy E. Karnabi
- SUNY Downstate Medical Center, Brooklyn, New York, United States of America
- Department of Research and Development VA Medical Center, Brooklyn, New York, United States of America
| | - Dushyant Damania
- SUNY Downstate Medical Center, Brooklyn, New York, United States of America
| | - Sunil Wadgaonkar
- Department of Research and Development VA Medical Center, Brooklyn, New York, United States of America
| | - Ilham A. Muslimov
- SUNY Downstate Medical Center, Brooklyn, New York, United States of America
| | - Raj Wadgaonkar
- SUNY Downstate Medical Center, Brooklyn, New York, United States of America
- Department of Research and Development VA Medical Center, Brooklyn, New York, United States of America
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24
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Modulation of cellular S1P levels with a novel, potent and specific inhibitor of sphingosine kinase-1. Biochem J 2012; 444:79-88. [DOI: 10.1042/bj20111929] [Citation(s) in RCA: 211] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
SphK (sphingosine kinase) is the major source of the bioactive lipid and GPCR (G-protein-coupled receptor) agonist S1P (sphingosine 1-phosphate). S1P promotes cell growth, survival and migration, and is a key regulator of lymphocyte trafficking. Inhibition of S1P signalling has been proposed as a strategy for treatment of inflammatory diseases and cancer. In the present paper we describe the discovery and characterization of PF-543, a novel cell-permeant inhibitor of SphK1. PF-543 inhibits SphK1 with a Ki of 3.6 nM, is sphingosine-competitive and is more than 100-fold selective for SphK1 over the SphK2 isoform. In 1483 head and neck carcinoma cells, which are characterized by high levels of SphK1 expression and an unusually high rate of S1P production, PF-543 decreased the level of endogenous S1P 10-fold with a proportional increase in the level of sphingosine. In contrast with past reports that show that the growth of many cancer cell lines is SphK1-dependent, specific inhibition of SphK1 had no effect on the proliferation and survival of 1483 cells, despite a dramatic change in the cellular S1P/sphingosine ratio. PF-543 was effective as a potent inhibitor of S1P formation in whole blood, indicating that the SphK1 isoform of sphingosine kinase is the major source of S1P in human blood. PF-543 is the most potent inhibitor of SphK1 described to date and it will be useful for dissecting specific roles of SphK1-driven S1P signalling.
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Spiegel S, Milstien S. The outs and the ins of sphingosine-1-phosphate in immunity. Nat Rev Immunol 2011; 11:403-15. [PMID: 21546914 DOI: 10.1038/nri2974] [Citation(s) in RCA: 633] [Impact Index Per Article: 48.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The potent lipid mediator sphingosine-1-phosphate (S1P) is produced inside cells by two closely related kinases, sphingosine kinase 1 (SPHK1) and SPHK2, and has emerged as a crucial regulator of immunity. Many of the actions of S1P in innate and adaptive immunity are mediated by its binding to five G protein-coupled receptors, designated S1PR1-5, but recent findings have also identified important roles for S1P as a second messenger during inflammation. In this Review, we discuss recent advances in our understanding of the roles of S1P receptors and describe the newly identified intracellular targets of S1P that are crucial for immune responses. Finally, we discuss the therapeutic potential of new drugs that target S1P signalling and functions.
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Affiliation(s)
- Sarah Spiegel
- Department of Biochemistry and Molecular Biology and the Massey Cancer Center, Virginia Commonwealth University School of Medicine, Richmond, Virginia 23298, USA.
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26
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Truman JP, Al Gadban MM, Smith KJ, Hammad SM. Acid sphingomyelinase in macrophage biology. Cell Mol Life Sci 2011; 68:3293-305. [PMID: 21533981 DOI: 10.1007/s00018-011-0686-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2011] [Revised: 03/28/2011] [Accepted: 04/05/2011] [Indexed: 12/21/2022]
Abstract
Macrophages play a central role in innate immune responses, in disposal of cholesterol, and in tissue homeostasis and remodeling. To perform these vital functions macrophages display high endosomal/lysosomal activities. Recent studies have highlighted that acid sphingomyelinase (ASMase), which generates ceramide from sphingomyelin, is involved in modulation of membrane structures and signal transduction in addition to its metabolic role in the lysosome. In this review, we bring together studies on ASMase, its different forms and locations that are necessary for the macrophage to accomplish its diverse functions. We also address the importance of ASMase to several disease processes that are mediated by activated macrophages.
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Affiliation(s)
- Jean-Philip Truman
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC 29425, USA
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27
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Expression of sphingosine kinase 1 in amoeboid microglial cells in the corpus callosum of postnatal rats. J Neuroinflammation 2011; 8:13. [PMID: 21310085 PMCID: PMC3050721 DOI: 10.1186/1742-2094-8-13] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2011] [Accepted: 02/11/2011] [Indexed: 11/21/2022] Open
Abstract
Sphingosine kinase 1 (SphK1), a key enzyme responsible for phosphorylating sphingosine into sphingosine-1-phosphate (S1P) has been shown to be expressed in monocytes and monocyte-derived peripheral macrophages. This study demonstrates SphK1 immunoexpression in amoeboid microglial cells (AMC), a nascent monocyte-derived brain macrophage in the corpus callosum of developing rat brain. SphK1 immunofluorescence expression, which appeared to be weak in AMC in normal brain, was markedly induced by lipopolysaccharide (LPS) or hypoxia treatment. Western blot analysis also showed increased expression level of SphK1 in the corpus callosum rich in AMC after LPS treatment. Detection of SphK1 mRNA and its upregulation after LPS treatment was confirmed in primary culture AMC by RT-PCR. Administration of N, N-dimethylsphingosine (DMS), a specific inhibitor of SphK1, effectively reduced upregulated SphK1 immunoexpression in AMC both in vivo and in vitro. This was corroborated by western blot which showed a decrease in SphK1 protein level of callosal tissue with DMS pretreatment. Remarkably, LPS-induced upregulation of the transcription factor NFκB was suppressed by DMS. We conclude that SphK1 expression in AMC may be linked to regulation of proinflammatory cytokines via an NFκB signaling pathway.
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28
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Kasper B, Petersen F. Molecular pathways of platelet factor 4/CXCL4 signaling. Eur J Cell Biol 2011; 90:521-6. [PMID: 21295372 DOI: 10.1016/j.ejcb.2010.12.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2010] [Revised: 12/20/2010] [Accepted: 12/21/2010] [Indexed: 10/25/2022] Open
Abstract
The platelet-derived chemokine CXCL4 takes a specific and unique position within the family of chemotactic cytokines. Today, much attention is directed to CXCL4's capacity to inhibit angiogenesis and to promote innate immune responses, which makes this chemokine an interesting tool and target for potential intervention in tumor growth and inflammation. However, such attempts demand a comprehensive knowledge on the molecular mechanisms and pathways underlying the corresponding cellular functions. At least two structurally different receptors, CXCR3-B and a chondroitin sulfate proteoglycan, are capable of binding CXCL4 and to induce a specific intracellular signaling machinery. While signaling mediated by CXCR3-B involves Gs proteins, elevated cAMP levels, and p38 MAP kinase, signaling via proteoglycans appears to be more complicated and varies strongly between the cell types analyzed. In CXCL4-activated neutrophils and monocytes, tyrosine kinases of the Src family and Syk as well as monomeric GTPases and members of the MAP kinase family have been identified as essential intracellular signals. Most intriguingly, signaling does not proceed in a linear sequence of events but in a repeated activation of certain transducing elements like Rac2 or sphingosine kinase 1. Depending on the downstream targets, such biphasic kinetics either leads to a redundant and prolonged activation of a single pathway or to a timely separated initiation of disparate signals and functions. Results of the studies reviewed here help to understand the molecular basis of CXCL4's functional diversity and provide insights into integrated signaling processes in general.
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Affiliation(s)
- Brigitte Kasper
- Department of Immunology and Cell Biology, Research Center Borstel, Parkallee 1-40, D-23845 Borstel, Germany
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Švajger U, Obermajer N, Jeras M. Novel Findings in Drug-Induced Dendritic Cell Tolerogenicity. Int Rev Immunol 2010; 29:574-607. [DOI: 10.3109/08830185.2010.522280] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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30
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Liu G, Zheng H, Zhang Z, Wu Z, Xiong H, Li J, Song L. Overexpression of sphingosine kinase 1 is associated with salivary gland carcinoma progression and might be a novel predictive marker for adjuvant therapy. BMC Cancer 2010; 10:495. [PMID: 20846391 PMCID: PMC2949806 DOI: 10.1186/1471-2407-10-495] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2010] [Accepted: 09/16/2010] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Overexpression of sphingosine kinase-1 (SPHK1) has been demonstrated to be associated with the development and progression in various types of human cancers. The current study was to characterize the expression of SPHK1 in salivary gland carcinomas (SGC) and to investigate the association between SPHK1 expression and progression of SGC. METHODS The expression of SPHK1 was examined in 2 normal salivary gland tissues, 8 SGC tissues of various clinical stages, and 5 pairs of primary SGC and adjacent salivary gland tissues from the same patient, using real-time PCR and western blot analysis. Furthermore, the SPHK1 protein expression was analyzed in 159 clinicopathologically characterized SGC cases by immunohistochemistry. Statistical analyses were performed to determine the prognostic and diagnostic associations. RESULTS SPHK1 expression was found to be markedly upregulated in SGC tissues than that in the normal salivary gland tissues and paired adjacent salivary gland tissues, at both mRNA and protein levels. Statistical analysis revealed a significant correlation of SPHK1 expression with the clinical stage (P = 0.005), T classification (P = 0.017), N classification (P = 0.009), M classification (P = 0.002), and pathological differentiation (P = 0.013). Patients with higher SPHK1 expression had shorter overall survival time, whereas patients with lower SPHK1 expression had better survival. Importantly, patients in the group without adjuvant therapy who exhibited high SPHK1 expression had significantly lower overall survival rates compared with those with low SPHK1 expression. Moreover, multivariate analysis suggested that SPHK1 expression might be an independent prognostic indicator for the survival of SGC patients. CONCLUSIONS Our results suggest that SPHK1 expression is associated with SGC progression, and might represent as a novel and valuable predictor for adjuvant therapy to SGC patients.
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Affiliation(s)
- Guanglin Liu
- State Key Laboratory of Oncology in Southern China, Department of Experimental Research, Cancer Center, Sun Yat-sen University, Guangzhou, Guangdong, China
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Pchejetski D, Nunes J, Coughlan K, Lall H, Pitson SM, Waxman J, Sumbayev VV. The involvement of sphingosine kinase 1 in LPS-induced Toll-like receptor 4-mediated accumulation of HIF-1α protein, activation of ASK1 and production of the pro-inflammatory cytokine IL-6. Immunol Cell Biol 2010; 89:268-74. [PMID: 20661259 DOI: 10.1038/icb.2010.91] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Toll-like receptors (TLRs) lie in the core of resistance to infectious diseases allowing host immune cells to specifically detect pathogens by recognising their specific molecular patterns. Cell membrane-associated TLR4 (recognises lipopolysaccharide (LPS) of Gram-negative bacteria) and endosomal TLR7/8 (recognise viral single-stranded RNA) are known to activate hypoxia inducible factor-1α (HIF-1α) protein (necessary for cellular adaptation to the inflammatory stress) via redox-dependent mechanism. TLR4 triggers the cross talk between HIF-1α and apoptosis signal-regulating kinase 1 (ASK1), whereas TLR7/8 activates HIF-1α in the ASK1-independent manner. Here, we report that in THP-1 and RAW264.7 macrophages, ligand-induced activation of the TLR4 but not TLR7/8 induces activation and transcriptional upregulation of sphingosine kinase 1 (SphK1) in extracellular signal-regulating kinase and phospholipase C-1γ/PI3 kinase-dependent manner. TLR4-mediated SphK1 activation was found to be critical for the redox-dependent activation of HIF-1α and ASK1, as well as for the prevention of LPS-induced activation of caspase 3 and the expression of pro-inflammatory cytokine interleukin-6.
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Affiliation(s)
- Dmitri Pchejetski
- Department of Oncology, Hammersmith hospital, Imperial College London, London, UK.
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HSP-70 mitigates LPS/SKI-induced cell damage by increasing sphingosine kinase 1 (SK1). Prostaglandins Other Lipid Mediat 2010; 92:1-7. [DOI: 10.1016/j.prostaglandins.2009.12.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2009] [Revised: 12/11/2009] [Accepted: 12/27/2009] [Indexed: 11/22/2022]
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Di A, Kawamura T, Gao XP, Tang H, Berdyshev E, Vogel SM, Zhao YY, Sharma T, Bachmaier K, Xu J, Malik AB. A novel function of sphingosine kinase 1 suppression of JNK activity in preventing inflammation and injury. J Biol Chem 2010; 285:15848-57. [PMID: 20299461 DOI: 10.1074/jbc.m109.075549] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
The mechanism underlying the protective effect of sphingosine kinase 1 (SphK1) in inflammatory injury is not clear. We demonstrated using SphK1-null mice (SphK1(-/-)) the crucial role of SphK1 in suppressing lipopolysaccharide-induced neutrophil oxidant production and sequestration in lungs and mitigating lung inflammatory injury. This effect of SphK1 was independent of the production of sphingosine 1-phosphate, the product of SphK1 activity. The anti-inflammatory effect of SphK1 in the lipopolysaccharide model was mediated through SphK1 interaction with JNK. SphK1 stabilization of JNK in turn inhibited JNK binding to the JNK-interacting protein 3 (JIP3) and thus abrogated the activation of NADPH oxidase and oxidant generation and resultant NF-kappaB activation. Therefore, SphK1-mediated down-regulation of JNK activity serves to dampen inflammation and tissue injury.
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Affiliation(s)
- Anke Di
- Department of Pharmacology, Center for Lung and Vascular Biology, University of Illinois, Chicago, Illinois 60612, USA.
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CXCL4-induced monocyte survival, cytokine expression, and oxygen radical formation is regulated by sphingosine kinase 1. Eur J Immunol 2010; 40:1162-73. [DOI: 10.1002/eji.200939703] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Zhao YD, Ohkawara H, Rehman J, Wary KK, Vogel SM, Minshall RD, Zhao YY, Malik AB. Bone marrow progenitor cells induce endothelial adherens junction integrity by sphingosine-1-phosphate-mediated Rac1 and Cdc42 signaling. Circ Res 2009; 105:696-704, 8 p following 704. [PMID: 19696411 DOI: 10.1161/circresaha.109.199778] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
RATIONALE Little is known about the contribution of bone marrow-derived progenitor cells (BMPCs) in the regulation endothelial barrier function as defined by microvascular permeability alterations at the level of adherens junctions (AJs). OBJECTIVE We investigated the role of BMPCs in annealing AJs and thereby in preventing lung edema formation induced by endotoxin (LPS). METHODS AND RESULTS We observed that BMPCs enhanced basal endothelial barrier function and prevented the increase in pulmonary microvascular permeability and edema formation in mice after LPS challenge. Coculture of BMPCs with endothelial cells induced Rac1 and Cdc42 activation and AJ assembly in endothelial cells. However, transplantation of BMPCs isolated from sphingosine kinase-1-null mice (SPHK1(-/-)), having impaired S1P production, failed to activate Rac1 and Cdc42 or protect the endothelial barrier. CONCLUSIONS These results demonstrate that BMPCs have the ability to reanneal endothelial AJs by paracrine S1P release in the inflammatory milieu and the consequent activation of Rac-1 and Cdc42 in endothelial cells.
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Affiliation(s)
- Yidan D Zhao
- Department of Pharmacology and Center for Lung and Vascular Biology, University of Illinois College of Medicine, Chicago, Ill. 60612, USA.
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Weigert A, Weis N, Brüne B. Regulation of macrophage function by sphingosine-1-phosphate. Immunobiology 2009; 214:748-60. [PMID: 19625101 DOI: 10.1016/j.imbio.2009.06.003] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The bioactive lipid sphingosine-1-phosphate (S1P) fulfils manifold tasks in the immune system acting in auto- and/or paracrine fashion. This includes regulation of apoptosis, migration and proliferation. Upon its generation by sphingosine kinases from plasma membrane sphingolipids, S1P can either act as a second messenger within cells or can be released from cells to occupy a family of specific G-protein-coupled receptors (S1P1-5). This diversity is reflected by the impact of S1P on macrophage biology and function. Over the last years it became apparent that the sphingosine kinase/S1P/S1P-receptor signalling axis in macrophages might play a central role in the pathogenesis of inflammatory diseases such as atherosclerosis, asthma, rheumatoid arthritis and cancer. Here, we summarize the current knowledge of the function of S1P in macrophage biology and discuss potential implications for pathology.
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Affiliation(s)
- Andreas Weigert
- Institute of Biochemistry I/ZAFES, Goethe-University Frankfurt am Main, Germany
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Issuree PDA, Pushparaj PN, Pervaiz S, Melendez AJ. Resveratrol attenuates C5a‐induced inflammatory responses
in vitro
and
in vivo
by inhibiting phospholipase D and sphingosine kinase activities. FASEB J 2009; 23:2412-24. [DOI: 10.1096/fj.09-130542] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
| | - Peter N. Pushparaj
- Department of PhysiologyYong Loo Lin School of MedicineSingapore
- Medicine‐Immunology, Infection, and InflammationGlasgow Biomedical Research CentreUniversity of GlasgowGlasgowUK
| | - Shazib Pervaiz
- Department of PhysiologyYong Loo Lin School of MedicineSingapore
- NUS Graduate School for Integrative Sciences and EngineeringSingapore
- Duke‐NUS Graduate Medical SchoolNational University of SingaporeSingapore
- Singapore‐Massachusetts Institute of Technology AllianceSingapore
| | - Alirio J. Melendez
- Department of PhysiologyYong Loo Lin School of MedicineSingapore
- NUS Graduate School for Integrative Sciences and EngineeringSingapore
- Medicine‐Immunology, Infection, and InflammationGlasgow Biomedical Research CentreUniversity of GlasgowGlasgowUK
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Li W, Yu CP, Xia JT, Zhang L, Weng GX, Zheng HQ, Kong QL, Hu LJ, Zeng MS, Zeng YX, Li M, Li J, Song LB. Sphingosine kinase 1 is associated with gastric cancer progression and poor survival of patients. Clin Cancer Res 2009; 15:1393-9. [PMID: 19228740 DOI: 10.1158/1078-0432.ccr-08-1158] [Citation(s) in RCA: 146] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
PURPOSE The present study was to investigate the clinical significance of sphingosine kinase 1 (SPHK1), an oncoenzyme, in the development and progression of gastric cancer. EXPERIMENTAL DESIGN mRNA and protein levels of SPHK1 expression in normal gastric epithelial cells, gastric cancer cell lines, and paired gastric cancer lesions and the adjacent noncancerous tissues were examined using reverse transcription-PCR and Western blotting. Immunohistochemistry was employed to analyze SPHK1 expression in 175 clinicopathologically characterized gastric cancer cases. Statistical analyses were applied to derive prognostic and diagnostic associations. RESULTS Levels of SPHK1 mRNA and protein were higher in gastric cancer cell lines than in normal gastric epithelial cells. SPHK1 protein level was up-regulated in gastric cancer lesions compared with that in the paired adjacent noncancerous tissues. Gastric cancer tissues from 115 of 175 (65.7%) patients revealed high level of SPHK1 protein expression in contrast to the undetectable or marginally detectable expression of SPHK1 in the adjacent noncancerous gastric tissues. Significantly different expression levels of SPHK1 were found in patients at different clinical stages (P=0.003), T classification (P=0.035), and M classification (P=0.020). Patients with higher SPHK1 expression had shorter overall survival time, whereas those with lower SPHK1 expression survived longer. Further multivariate analysis suggested that SPHK1 up-regulation was an independent prognostic indicator for the disease. CONCLUSIONS SPHK1 protein could be a useful marker for the prognosis of gastric cancer. Further study on the potential use of SPHK1 as a therapeutic target is also warranted.
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Affiliation(s)
- Wen Li
- State Key Laboratory of Oncology in Southern China, Department of Experimental Research, Cancer Center, Guangzhou, China
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Role of p38 and early growth response factor 1 in the macrophage response to group B streptococcus. Infect Immun 2009; 77:2474-81. [PMID: 19332535 DOI: 10.1128/iai.01343-08] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Group B streptococcus (GBS), the most frequent single isolate in neonatal sepsis and meningitis, potently activates inflammatory macrophage genes via myeloid differentiation antigen 88 (MyD88). However, events parallel to and downstream of MyD88 that instruct the macrophage response are incompletely understood. In this study, we found that only MyD88, not the Toll-like receptor (TLR) adapter proteins MAL/TIRAP, TRIF, and TRAM, essentially mediates the cytokine (tumor necrosis factor [TNF] and interleukin-6) and chemokine (RANTES) responses to whole GBS organisms, although MAL, TRIF, and TRAM have been shown to mediate the responses to substructures in other gram-positive and gram-negative bacteria. GBS-induced, MyD88-dependent phosphorylation of the mitogen-activated protein kinase p38 activated the transcription factor AP-1 and early growth response factor 1 (Egr-1) but not NF-kappaB. Furthermore, phosphorylation of Ets-like molecule 1 (Elk-1) was mediated by p38. However, in contrast to Egr-1 and AP-1, Elk-1 was dispensable for transcriptional activation of TNF by GBS organisms. Studies of macrophages from Elk-1-deficient mice revealed that Elk-1 was furthermore nonessential for the TNF responses to purified TLR2 and TLR4 agonists, which was in notable contrast to what was revealed in studies employing in vitro expression systems. In conclusion, MyD88, p38, and Egr-1, but not Elk-1, essentially mediate the inflammatory cytokine response to GBS organisms.
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Price MM, Oskeritzian CA, Milstien S, Spiegel S. Sphingosine-1-phosphate synthesis and functions in mast cells. ACTA ACUST UNITED AC 2008; 3:665-674. [PMID: 19802381 DOI: 10.2217/17460875.3.6.665] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Sphingolipids are not only major lipid components of all eukaryotic cell membranes, but they also comprise an important family of bioactive signaling molecules that regulate a diverse array of biological responses. The sphingolipid metabolite sphingosine-1-phosphate (S1P), is a key regulator of immune responses. Cellular levels of S1P are determined by the balance between its synthesis, involving two sphingosine kinases (SphK1 and SphK2), and its degradation, involving S1P lyase and S1P phosphatases. S1P mainly signals through its cell-surface receptors and may also have intracellular functions. S1P has important functions in mast cells - the major effectors of allergic responses. Antigen triggering of IgE receptors on mast cells activates both SphKs resulting in the production of S1P that is released and regulates and amplifies mast cell functions, including degranulation as well as cytokine and chemokine release.
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Affiliation(s)
- Megan M Price
- Department of Biochemistry & Molecular Biology, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, USA, Tel.: +1 804 828 9332
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Statins inhibit toll-like receptor 4-mediated lipopolysaccharide signaling and cytokine expression. Pharmacogenet Genomics 2008; 18:803-13. [PMID: 18698233 DOI: 10.1097/fpc.0b013e3283050aff] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Toll-like receptor 4 (TLR4) is the main receptor for Lipopolysaccharide (LPS). Two relatively common variants of the TLR4 gene are present, resulting in changes from aspartic acid (D) to glycine (G) at residue 299 and from threonine (T) to isoleucine (I) at residue 399, respectively. It has been shown that statins have a greater effect on lowering risk of cardiovascular events in individuals carrying the 299G allele than in those not carrying this allele. We investigated possible mechanisms underlying this synergy of statin treatment and TLR4 genotype. METHODS AND RESULTS In cells expressing the 299D-399T TLR4, LPS activated the transcription factor NFkappaB and increased the expression of interleukin-6 and tumor necrosis factor-alpha, and these effects were reduced by pretreatment of the cells with pravastatin or simvastatin. LPS-induced NFkappaB activation and interleukin-6 and tumor necrosis factor-alpha expression were substantially reduced in cell expressing the 299G-399T or 299D-399I variant, and undetectable in cells expressing the 299G-399I TLR4. The 3-hydroxy-3-methylglutaryl coenzyme A pathway inhibitors, Y27632 and GGTI-286, exhibited a similar effect to statins, suggesting that the inhibitory effect of statins was mediated by the 3-hydroxy-3-methylglutaryl coenzyme A pathway. CONCLUSION The results of this study indicate that the TLR4 variations and statins have an additive inhibitory effect on TLR4-mediated inflammatory response, providing a potential explanation for the finding that the beneficial effect of statins on cardiovascular risk is dependent on TLR4 genotype.
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Cheon S, Song SB, Jung M, Park Y, Bang JW, Kim TS, Park H, Kim CH, Yang YH, Bang SI, Cho D. Sphingosine kinase inhibitor suppresses IL-18-induced interferon-gamma production through inhibition of p38 MAPK activation in human NK cells. Biochem Biophys Res Commun 2008; 374:74-8. [DOI: 10.1016/j.bbrc.2008.06.091] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2008] [Accepted: 06/25/2008] [Indexed: 01/24/2023]
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Abstract
Pharmacological interference with sphingolipid metabolizing enzymes promises to provide novel ways to modulate cellular pathways relevant in multiple diseases. In this review, we focus on two sphingolipid signaling molecules, sphingosine-1-phosphate (S1P) and ceramide, as they are involved in cell fate decisions (survival vs. apoptosis) and in a wide range of pathophysiological processes. For S1P, we will discuss sphingosine kinases and S1P lyase as the enzymes which are crucial for its production and degradation, respectively, emphasizing the potential therapeutic usefulness of inhibitors of these enzymes. For ceramide, we will concentrate on acid sphingomyelinase, and critically review the substantial literature which implicates this enzyme as a worthwhile target for pharmacological inhibitors. It will become clear that the task to validate these enzymes as drug targets is not finished and many questions regarding the therapeutic usefulness of their inhibitors remain unanswered. Still this approach holds promise for a number of totally new therapies, and, on the way, detailed insight into sphingolipid signaling pathways can be gained.
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Affiliation(s)
- Andreas Billich
- Novartis Institutes for BioMedical Research, Brunnerstrasse 59, A-1235 Vienna, Austria
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Dual and distinct roles for sphingosine kinase 1 and sphingosine 1 phosphate in the response to inflammatory stimuli in RAW macrophages. Prostaglandins Other Lipid Mediat 2007; 85:107-14. [PMID: 18166496 DOI: 10.1016/j.prostaglandins.2007.11.002] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2007] [Revised: 11/15/2007] [Accepted: 11/16/2007] [Indexed: 12/23/2022]
Abstract
Sphingosine kinase 1 (SK1) and its product sphingosine-1-phosphate (S1P) have been implicated in the regulation of many cellular processes including growth regulation, protection from apoptosis, stimulation of angiogenesis, and most recently as mediators of the TNF-alpha inflammatory response. In this study we set out to examine the role of SK1/S1P in the RAW macrophage response to the potent inflammatory stimulus lipopolysaccharide (LPS). We show that LPS increases cellular levels of SK1 message and protein. This increase is at the transcriptional level and is accompanied by increased SK activity and generation of S1P. S1P is able to cause increases in COX-2 and PGE2 levels in RAW cells. Knockdown of SK1 using siRNA is able to inhibit the TNF but not the LPS inflammatory response. Moreover, knockdown of SK1 enhances both TNF- and LPS-induced apoptosis. These data indicate that there is a dual and distinct role for SK1 and S1P in the TNF and the LPS inflammatory pathways.
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Li QF, Wu CT, Duan HF, Sun HY, Wang H, Lu ZZ, Zhang QW, Liu HJ, Wang LS. Activation of sphingosine kinase mediates suppressive effect of interleukin-6 on human multiple myeloma cell apoptosis. Br J Haematol 2007; 138:632-9. [PMID: 17686057 DOI: 10.1111/j.1365-2141.2007.06711.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Interleukin 6 (IL-6) influences the growth and survival of multiple myeloma (MM) cells via the activation of multiple signalling cascades. Although sphingosine kinase (SPHK) signalling is known to play important roles in the regulation of cell proliferation and apoptosis, the role of SPHK activation in IL-6 signalling and in the pathology of MM remains unclear. This study found that IL-6 activated SPHK in MM cells, which mediates the suppressive effects of IL-6 on MM cell apoptosis. Both MM cell lines and primary MM cells constitutively expressed SPHK, and treatment of MM cells with IL-6 resulted in activation of SPHK in a concentration-dependent manner. Specific inhibitors of the phosphatidylinositol-3 kinase and extracellular signal-regulated kinase/mitogen-activated protein kinase pathways blocked the IL-6-induced activation of SPHK. It was further demonstrated that IL-6-induced activation of SPHK inhibited dexamethasone-induced apoptosis of MM cells. IL-6 stimulation or retroviral-mediated overexpression of SPHK1 in MM cells resulted in increased intracellular SPHK activity and upregulation of myeloid cell leukaemia-1 (Mcl-1), leading to increased cell proliferation and survival. Conversely, inhibition of SPHK1 by small interfering RNA reduced IL-6-induced upregulation of Mcl-1 and blocked the suppressive effect of IL-6 on MM cell apoptosis. Taken together, these results delineate a key role for SPHK activation in IL-6-induced proliferation and survival of MM cells, and suggest that SPHK may be a potential new therapeutic target in MM.
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Affiliation(s)
- Qing-Fang Li
- Department of Experimental Haematology, Beijing Institute of Radiation Medicine, Beijing, China
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Méndez-Samperio P, Pérez A, Trejo A. Sphingosine kinase, phosphatidylinositol 3-kinase, Akt, NF-κB, and p300 are required for CCL5 production in Mycobacterium bovis Bacillus Calmette–Guérin (BCG)-infected epithelial cells. Cell Immunol 2007; 249:94-100. [DOI: 10.1016/j.cellimm.2007.11.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2007] [Revised: 11/27/2007] [Accepted: 11/28/2007] [Indexed: 01/23/2023]
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47
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Alvarez SE, Milstien S, Spiegel S. Autocrine and paracrine roles of sphingosine-1-phosphate. Trends Endocrinol Metab 2007; 18:300-7. [PMID: 17904858 DOI: 10.1016/j.tem.2007.07.005] [Citation(s) in RCA: 246] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2007] [Revised: 07/18/2007] [Accepted: 07/18/2007] [Indexed: 11/16/2022]
Abstract
Sphingosine-1-phosphate (S1P) is a bioactive sphingolipid metabolite that has been implicated in many biological processes, including cell migration, survival, proliferation, angiogenesis and immune and allergic responses. S1P levels inside cells are regulated tightly by the balance between its synthesis by sphingosine kinases and degradation by S1P lyases and S1P phosphatases. Activation of sphingosine kinase by any of a variety of agonists increases S1P levels, which in turn can function intracellularly as a second messenger or in an autocrine and/or paracrine fashion to activate and signal through S1P receptors present on the surface of the cell. This review summarizes recent findings on the roles of S1P as a mediator of the actions of cytokines, growth factors and hormones.
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Affiliation(s)
- Sergio E Alvarez
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, USA
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Li QF, Huang WR, Duan HF, Wang H, Wu CT, Wang LS. Sphingosine kinase-1 mediates BCR/ABL-induced upregulation of Mcl-1 in chronic myeloid leukemia cells. Oncogene 2007; 26:7904-8. [PMID: 17599053 DOI: 10.1038/sj.onc.1210587] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The signaling mechanisms responsible for BCR/ABL-induced regulation of Mcl-1 expression in chronic myelogenous leukemia (CML) cells remain unclear. In this study, we show that BCR/ABL could upregulate sphingosine kinase-1 (SPK1) expression via multiple signal pathways, including mitogen-activated protein kinase (MAPK), phosphoinositide 3-kinase (PI3K) and Janus kinase 2 (JAK2), leading to increase cellular SPK1 activity in CML cells. Retrovirus-mediated overexpression of bcr-abl gene in NIH-3T3, Ba/F3 and HL-60 cells results in upregulation and increased cellular activity of SPK1, whereas treatment of CML cells with specific inhibitors of the BCR/ABL, PI3K, MAPK and JAK2 pathways decreases BCR/ABL-induced SPK1 expression and cellular activity. BCR/ABL also induces upregulation of Mcl-1 expression in CML cells. Inhibition of SPK1 by adenovirus-mediated transfer of small interfering RNA or N,N-dimethylsphingosine reduced expression of Mcl-1 in CML cells. Our data indicated that BCR/ABL induces SPK1 expression and increases its cellular activity, leading to upregulation of Mcl-1 in CML cells. SPK1 silencing enhances the STI571-induced apoptosis of CML cell lines. It is suggested that SPK1 may be a potential therapeutic target in CML.
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Affiliation(s)
- Q-F Li
- Department of Experimental Hematology, Beijing Institute of Radiation Medicine, Beijing, PR China
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49
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Kim HJ, Lee Y, Chang EJ, Kim HM, Hong SP, Lee ZH, Ryu J, Kim HH. Suppression of osteoclastogenesis by N,N-dimethyl-D-erythro-sphingosine: a sphingosine kinase inhibition-independent action. Mol Pharmacol 2007; 72:418-28. [PMID: 17504945 DOI: 10.1124/mol.107.034173] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
N,N-Dimethyl-D-erythro-sphingosine (DMS) competitively inhibits sphingosine kinase (SPHK) and has been widely used to assess the role of SPHK during cellular events, including motility, proliferation, and differentiation. In the present study, the effect of DMS on the differentiation of bone marrow macrophages (BMMs) to osteoclasts was investigated. When the osteoclast precursor cells were treated with DMS, the receptor activator of nuclear factor kappaB ligand (RANKL)-induced osteoclastogenesis was completely blocked. We were surprised to find, however, that knock-down of SPHK by small interfering RNA (siRNA) in BMMs did not reduce osteoclastogenesis. Furthermore, both overexpression of SPHK and exogenous addition of sphingosine-1-phosphate, the product of SPHK activity, failed to overcome the antiosteoclastogenic effect of DMS. These results suggest that DMS inhibited osteoclastogenesis independently of SPHK. Subsequent characterization of the DMS-mediated suppression of osteoclastogenesis revealed that DMS did not affect RANKL-induced activation of JNK, p38, NF-kappaB, and Ca2+ oscillation. On the other hand, DMS strongly inhibited two separate signaling pathways, the RANKL-induced activation of ERK and Akt, which eventually converged on the transcription factors c-Fos and NFATc1. There was significant increase in the osteoclast formation in the presence of DMS when BMMs were overexpressed with c-Fos, suggesting that c-Fos was a critical downstream target of DMS for the inhibition of osteoclastogenesis. Taken together, our data demonstrate that DMS has an antiosteoclastogenic function independently of its SPHK inhibitory activity. Considering previously reported anticancer properties of DMS, our study may also propose that DMS is an ideal drug candidate for bone metastases, for which osteoclastic bone-resorption is crucial.
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Affiliation(s)
- Hyung Joon Kim
- Department of Cell and Developmental Biology, Seoul National University, 28 Yeongon-Dong, Chongno-Gu, Seoul 110-749, Korea
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50
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Le Stunff H, Raymond MN. P2X7 receptor-mediated phosphatidic acid production delays ATP-induced pore opening and cytolysis of RAW 264.7 macrophages. Cell Signal 2007; 19:1909-18. [PMID: 17540539 DOI: 10.1016/j.cellsig.2007.04.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2007] [Accepted: 04/30/2007] [Indexed: 12/19/2022]
Abstract
In macrophages, extracellular ATP (ATPe) stimulation of P2X7 receptors (P2X7R) results in cation channel opening, non-specific pore formation, secretion of cytokines, killing of intracellular bacteria and cytolysis. Signaling pathways controlling these diverse responses are currently under investigation. Among these pathways, phospholipase D (PLD) has been implicated in P2X7R-activated macrophages killing of intracellular pathogenic bacteria. Here we present evidence that early P2X7R-mediated PLD activation reduces pore opening and delays cytolysis of RAW 267.4 macrophages induced by ATPe. Use of inhibitors of PA metabolic enzymes suggests that PA, and not one of its metabolites, is the bioactive lipid. This is strengthened by the observation that addition of exogenous PA also reduces pore formation and cytolysis of RAW 264.7 macrophages. However, the beneficial effects of PA are only transient, due to its conversion into diacylglycerol through PA phosphatase-1 activity during prolonged P2X7R stimulation. Revealing that the PLD/PA pathway mediates survival of macrophages provides a potent strategy to inhibit P2X7R-mediated cytolysis by controlling PA metabolism. This will be important in the case of P2X7R-induced killing of intracellular bacteria which is lately associated with macrophage death, limiting the potency of ATPe to eliminate pathogenic bacteria.
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Affiliation(s)
- Hervé Le Stunff
- Institut de Biochimie et de Biophysique Moléculaire et Cellulaire, CNRS UMR 8619, Université Paris Sud, 91405 Orsay cedex, France.
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