FTY720, a sphingosine-1-phosphate (S1P) receptor modulator, protects sinusoid endothelial cells from radiation injury in vitro

Chloride intracellular channels 1 (CLIC1) and 4 (CLIC4) are expressed in endothelial cells and regulate angiogenic behaviors in vitro, and the expression of Clic4 is important for vascular development and function in mice. Here, we found that CLIC1 and CLIC4 in endothelial cells regulate critical G protein–coupled receptor (GPCR) pathways associated with vascular development and disease. In cultured endothelial cells, we found that CLIC1 and CLIC4 transiently translocated to the plasma membrane in response to sphingosine 1-phosphate (S1P). Both CLIC1 and CLIC4 were essential for mediating S1P-induced activation of the small guanosine triphosphatase (GTPase) Rac1 downstream of S1P receptor 1 (S1PR1). In contrast, only CLIC1 was essential for S1P-induced activation of the small GTPase RhoA downstream of S1PR2 and S1PR3. Neither were required for other S1P-S1PR signaling outputs. Rescue experiments revealed that CLIC1 and CLIC4 were not functionally interchangeable, suggesting distinct and specific functions for CLICs in transducing GPCR signaling. These CLIC-mediated mechanisms were critical for S1P-induced stimulation of the barrier function in endothelial cell monolayers. Our results define CLICs as previously unknown players in the pathways linking GPCRs to small GTPases and vascular endothelial function.

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Abstract 23: Microrna302-367 Sphingosine 1 Phosphate Receptor 1 Pathway Prevents Tumor Growth via Restricting Angiogenesis and Enhancing Vascular Stability

Arteriosclerosis Thrombosis and Vascular Biology ◽

10.1161/atvb.36.suppl_1.23 ◽

2016 ◽

Vol 36 (suppl_1) ◽

Author(s):

Jinjiang Pi ◽

Ting Tao ◽

Tao Zhuang ◽

Huimin Sun ◽

Xiaoli Chen ◽

...

Keyword(s):

Endothelial Cells ◽

Tumor Growth ◽

Ex Vivo ◽

Downstream Target ◽

Sprouting Angiogenesis ◽

Pathological Angiogenesis ◽

Vascular Stability ◽

Sphingosine 1 Phosphate

Angiogenic hypersprouting and leaky immature vessels of pathological angiogenesis are essential for tumor growth. MicroRNAs have unique therapeutic advantages by targeting multiple pathways of tumor-associated angiogenesis, but the function of individual miRNAs in angiogenesis and tumors has not yet been fully evaluated. Here, we show that miR302-367 elevation in endothelial cells reduces retina sprouting angiogenesis and promotes vascular stability in vivo, ex vivo and in vitro. Erk1/2 are identified as direct targets of miR302-367, and down-regulation of Erk1/2 upon miR302-367 elevation in endothelial cells increases the expression of Klf2 and in turn S1pr1 and its downstream target VE-cadherin, suppressing angiogenesis and improving vascular stability. Conversely, both pharmacological blockade and genetic deletion of S1pr1 in endothelial cells reverse the anti-angiogenic and vascular stabilizing effect of miR302-367 in mice. Pathological angiogenesis in tumors shares features of developmental angiogenesis, and endothelial specific elevation of miR302-367 reduces tumor growth by restricting sprout angiogenesis and decreasing vascular permeability via the same Erk1/2-Klf2-S1pr1 pathways. In conclusion, miR302-367 regulation of an Erk1/2-Klf2-S1pr1 pathway in the endothelium advances our understanding of angiogenesis, meanwhile also provides opportunities for therapeutic intervention of tumor growth.

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Sphingosine‐1‐phosphate (S1P) induces potent anti‐inflammatory effects in vitro and in vivo by S1P receptor 4‐mediated suppression of 5‐lipoxygenase activity

The FASEB Journal ◽

10.1096/fj.201800221r ◽

2018 ◽

Vol 33 (2) ◽

pp. 1711-1726 ◽

Cited By ~ 10

Author(s):

Jasmin Fettel ◽

Benjamin Kühn ◽

Nathalie A. Guillen ◽

Duran Sürün ◽

Marcus Peters ◽

...

Keyword(s):

Lipoxygenase Activity ◽

Sphingosine 1 Phosphate ◽

S1p Receptor ◽

Anti Inflammatory

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Activation of the Sphingosine 1 Phosphate–Rho Pathway in Pterygium and in Ultraviolet-Irradiated Normal Conjunctiva

International Journal of Molecular Sciences ◽

10.3390/ijms20194670 ◽

2019 ◽

Vol 20 (19) ◽

pp. 4670 ◽

Cited By ~ 1

Author(s):

Nozomi Igarashi ◽

Megumi Honjo ◽

Takashi Fujishiro ◽

Tetsuya Toyono ◽

Takashi Ono ◽

...

Keyword(s):

Fibroblast Cell ◽

Cellular Activity ◽

Myosin Phosphatase ◽

Potential Therapeutic Target ◽

Interacting Protein ◽

Cytoskeletal Organization ◽

Rhoa Activity ◽

Sphingosine 1 Phosphate ◽

S1p Receptor

Sphingosine 1 phosphate (S1P) is a bioactive lipid that regulates cellular activity, including proliferation, cytoskeletal organization, migration, and fibrosis. In this study, the potential relevance of S1P–Rho signaling in pterygium formation and the effects of ultraviolet (UV) irradiation on activation of the S1P/S1P receptor axis and fibrotic responses were investigated in vitro. Expressions of the S1P2, S1P4, and S1P5 receptors were significantly higher in pterygium tissue than in normal conjunctiva, and the concentration of S1P was significantly elevated in the lysate of normal conjunctival fibroblast cell (NCFC) irradiated with UV (UV-NCFCs). RhoA activity was significantly upregulated in pterygium fibroblast cells (PFCs) and UV-NCFCs, and myosin phosphatase–Rho interacting protein (MRIP) was upregulated, and myosin phosphatase target subunit 1 (MYPT1) was downregulated in PFCs. Fibrogenic changes were significantly upregulated in both PFCs and UV-NCFCs compared to NCFCs. We found that the activation of the S1P receptor–Rho cascade was observed in pterygium tissue. Additionally, in vitro examination showed S1P–rho activation and fibrogenic changes in PFCs and UV-NCFCs. S1P elevation and the resulting upregulation of the downstream Rho signaling pathway may be important in pterygium formation; this pathway offers a potential therapeutic target for suppressing pterygium generation.

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Sphingosine 1-phosphate receptor 1 regulates the directional migration of lymphatic endothelial cells in response to fluid shear stress

Journal of The Royal Society Interface ◽

10.1098/rsif.2016.0823 ◽

2016 ◽

Vol 13 (125) ◽

pp. 20160823 ◽

Cited By ~ 6

Author(s):

Vinay N. Surya ◽

Eleftheria Michalaki ◽

Eva Y. Huang ◽

Gerald G. Fuller ◽

Alexander R. Dunn

Keyword(s):

Endothelial Cells ◽

Fluid Flow ◽

Molecular Mechanisms ◽

Fluid Shear Stress ◽

Lymphatic Vessels ◽

Upstream Migration ◽

Lymphatic Endothelial Cells ◽

Sphingosine 1 Phosphate ◽

G Protein Coupled

The endothelial cells that line blood and lymphatic vessels undergo complex, collective migration and rearrangement processes during embryonic development, and are known to be exquisitely responsive to fluid flow. At present, the molecular mechanisms by which endothelial cells sense fluid flow remain incompletely understood. Here, we report that both the G-protein-coupled receptor sphingosine 1-phosphate receptor 1 (S1PR1) and its ligand sphingosine 1-phosphate (S1P) are required for collective upstream migration of human lymphatic microvascular endothelial cells in an in vitro setting. These findings are consistent with a model in which signalling via S1P and S1PR1 are integral components in the response of lymphatic endothelial cells to the stimulus provided by fluid flow.

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More than Just an Immunosuppressant: The Emerging Role of FTY720 as a Novel Inducer of ROS and Apoptosis

Oxidative Medicine and Cellular Longevity ◽

10.1155/2018/4397159 ◽

2018 ◽

Vol 2018 ◽

pp. 1-13 ◽

Cited By ~ 9

Author(s):

Teruaki Takasaki ◽

Kanako Hagihara ◽

Ryosuke Satoh ◽

Reiko Sugiura

Keyword(s):

Cancer Treatment ◽

Defense Mechanisms ◽

Chemotherapeutic Agents ◽

Future Directions ◽

Receptor Modulator ◽

Cystine Transporter ◽

Sphingosine 1 Phosphate ◽

S1p Receptor ◽

Fingolimod Hydrochloride

Fingolimod hydrochloride (FTY720) is a first-in-class of sphingosine-1-phosphate (S1P) receptor modulator approved to treat multiple sclerosis by its phosphorylated form (FTY720-P). Recently, a novel role of FTY720 as a potential anticancer drug has emerged. One of the anticancer mechanisms of FTY720 involves the induction of reactive oxygen species (ROS) and subsequent apoptosis, which is largely independent of its property as an S1P modulator. ROS have been considered as a double-edged sword in tumor initiation/progression. Intriguingly, prooxidant therapies have attracted much attention due to its efficacy in cancer treatment. These strategies include diverse chemotherapeutic agents and molecular targeted drugs such as sulfasalazine which inhibits the CD44v-xCT (cystine transporter) axis. In this review, we introduce our recent discoveries using a chemical genomics approach to uncover a signaling network relevant to FTY720-mediated ROS signaling and apoptosis, thereby proposing new potential targets for combination therapy as a means to enhance the antitumor efficacy of FTY720 as a ROS generator. We extend our knowledge by summarizing various measures targeting the vulnerability of cancer cells’ defense mechanisms against oxidative stress. Future directions that may lead to the best use of FTY720 and ROS-targeted strategies as a promising cancer treatment are also discussed.

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Sphingosine-1-phosphate receptor expression in cardiac fibroblasts is modulated by in vitro culture conditions

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.01065.2006 ◽

2007 ◽

Vol 292 (6) ◽

pp. H2698-H2711 ◽

Cited By ~ 16

Author(s):

Lee K. Landeen ◽

Nakon Aroonsakool ◽

Jason H. Haga ◽

Betty S. Hu ◽

Wayne R. Giles

Keyword(s):

Transforming Growth Factor ◽

Kinase Inhibitor ◽

Cardiac Fibroblasts ◽

Culture Conditions ◽

Receptor Expression ◽

Receptor Subtypes ◽

Essential Components ◽

Sphingosine 1 Phosphate ◽

S1p Receptor

The bioactive molecule sphingosine-1-phosphate (S1P) binds with high affinity to five recognized receptors (S1P1–5) to affect various tissues, including cellular responses of cardiac fibroblasts (CFbs) and myocytes. CFbs are essential components of myocardium, and detailed study of their cell signaling and physiology is required for a number of emerging disciplines. Meaningful studies on CFbs, however, necessitate methods for selective, reproducible cell isolations. Macrophages reside within normal cardiac tissues and often are isolated with CFbs. A protocol was therefore developed that significantly reduces macrophage levels and utilizes more CFb-specific markers (discoidin domain receptor-2) instead of, or in addition to, more commonly used cytoskeletal markers. Our results demonstrate that primary isolated, purified CFbs express predominantly S1P1–3; however, the relative levels of these receptor subtypes are modulated with time and by culture conditions. In coculture experiments, macrophages altered CFb S1P receptor levels relative to controls. Further investigations using known macrophage-secreted factors showed that S1P and H2O2 had minimal effects on CFb S1P1–3 expression, whereas transforming growth factor-β1, TNF-α, and PDGF-BB significantly altered all S1P receptor subtypes. Lowering FBS concentrations from 10% to 0.1% increased S1P2, whereas supplementation with either PDGF-BB or Rho-associated protein kinase inhibitor Y-27632 significantly elevated S1P3 levels. S1P2 and S1P3 receptor levels are known to regulate cell migration. Using cells isolated from either normal or S1P3-null mice, we demonstrate that S1P3 is important and necessary for CFb migration. These results highlight the importance of demonstrating CFb culture purity in functional studies of S1P and also identify conditions that modulate S1P receptor expression in CFbs.

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FTY720 requires vitamin B12-TCN2-CD320 signaling in astrocytes to reduce disease in an animal model of multiple sclerosis

10.1101/2022.01.10.475450 ◽

2022 ◽

Author(s):

Deepa Jonnalagadda ◽

Yasuyuki Kihara ◽

Aran Groves ◽

Manisha Ray ◽

Arjun Saha ◽

...

Keyword(s):

Multiple Sclerosis ◽

Metabolic Pathways ◽

Type I ◽

Rna Seq ◽

Autoimmune Encephalomyelitis ◽

Altered Expression ◽

Receptor Modulator ◽

Sphingosine 1 Phosphate ◽

Sphingosine Kinases ◽

S1p Receptor

FTY720 (fingolimod) is a sphingosine 1-phosphate (S1P) receptor modulator and sphingosine analogue approved for multiple sclerosis (MS) therapy, which can functionally antagonize the S1P receptor, S1P1. Vitamin B12 (B12) deficiency produces neurological manifestations resembling MS. Here, we report a new mechanism where FTY720 suppresses neuroinflammation by regulating B12 metabolic pathways. Nuclear RNA-seq of c-Fos-activated astrocytes (called ieAstrocytes) from experimental autoimmune encephalomyelitis (EAE) spinal cords identified up-regulation of CD320, a transcobalamin 2 (TCN2)-B12 receptor, by S1P1 inhibition. CD320 was reduced in MS plaques. Deficiency of CD320 or dietary B12 worsened EAE and eliminated FTY720 efficacy, while concomitantly down-regulating type I interferon signaling. TCN2 functioned as a chaperone for FTY720 and sphingosine, which induced astrocytic CD320 internalization. An accompanying paper identified a requirement for astrocyte sphingosine kinases in FTY720 efficacy and its altered expression in MS brains, molecularly linking MS and B12 deficiency that can be accessed by sphingolipid/fingolimod metabolic pathways.

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Ozanimod for the treatment of relapsing forms of multiple sclerosis

Neurodegenerative Disease Management ◽

10.2217/nmt-2021-0005 ◽

2021 ◽

Author(s):

Andrea M Kuczynski ◽

Jiwon Oh

Keyword(s):

Multiple Sclerosis ◽

Clinical Trials ◽

Side Effects ◽

Receptor Subtypes ◽

Efficacy And Safety ◽

S1p Receptors ◽

Receptor Modulator ◽

Wide Range ◽

Sphingosine 1 Phosphate ◽

S1p Receptor

Multiple sclerosis (MS) is an inflammatory disease that causes chronic neurological disability in young adults. Modulation of sphingosine 1-phosphate (S1P) receptors, a group of receptors that, among other things, regulate egression of lymphocytes from lymph nodes, has proven to be effective in treating relapsing MS. Fingolimod, the first oral S1P receptor modulator, has demonstrated potent efficacy and tolerability, but can cause undesirable side effects due to its interaction with a wide range of S1P receptor subtypes. This review will focus on ozanimod, a more selective S1P receptor modulator, which has recently received approval for relapsing MS. We summarize ozanimod’s mechanism of action, and efficacy and safety from clinical trials that demonstrate its utility as another treatment option for relapsing MS.

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