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Effects of sphingosine, staurosporine, and phorbol ester on neurites of rat sympathetic neurons growing in compartmented cultures.

Local application of sphingosine (1-10 microM), an inhibitor of protein kinase C, to NGF-supplied, distal neurites of rat sympathetic neurons in compartmented cultures caused their retraction and/or degeneration within 24 hr. This effect was specific for distal neurites because sphingosine (even at 100 microM) applied to cell bodies and/or proximal neurites did not destroy these regions of the cells, and their distal neurites continued to elongate. However, effects of other agents suggest that the retraction/degeneration observed in distal neurites directly exposed to sphingosine is not mediat…

Sphingosine-1-phosphate induces angiogenesis via the activating STAT3 signaling pathway to drive colorectal cancer progression.

BACKGROUND: Tumor angiogenesis is a characteristic hallmark of carcinogenesis. Sphingosine-1-phosphate (S1P), a key bioactive lipid produced in vivo, drives the progression of multiple malignant tumors. This study aimed to investigate the function of S1P-mediated angiogenesis in the progression of colorectal cancer (CRC). METHODS: CD31 expression was detected by immunohistochemistry, while serum levels of S1P and CD31 were measured by enzyme-linked immunosorbent assay (ELISA). The regulatory network linking S1P to STAT3/VEGFA was analyzed via the Search Tool for Interacting Chemicals (STITCH)…

Sphingosine-1-phosphate promotes CD8 T cell exhaustion in breast cancer via exosomal transfer of TGFBR2.

Sphingosine-1-phosphate (S1P) has been implicated in promoting breast cancer progression, but its role in fostering an immunosuppressive microenvironment remains largely unexplored. In our study, co-culturing CD8 T cells with S1P-treated MCF7 cells significantly reduced CD8 T cell proliferation, an effect reversed by inhibiting exosome biogenesis. S1P treatment enhanced exosome release from breast cancer cells, with increased levels of TGFBR2 detected on the exosome surface. These S1P-induced exosomes promoted CD8 T cell exhaustion. Silencing TGFBR2 in cancer cells or treating with anti-TGFBR2…

Sphingosine-1-Phosphate Attenuates LPS-Induced Inflammatory Cardiac Injury in Association With RASGRP1-S100A9-NLRP3 Signaling.

Lipopolysaccharide (LPS) induces endotoxemia-associated inflammatory cardiac injury rather than classical viral or autoimmune myocarditis. Sphingosine-1-phosphate (S1P) regulates cardiovascular and immune responses, predominantly through S1P receptors, but whether it also modulates macrophage-associated inflammatory signaling during LPS-induced cardiac injury remains incompletely understood. This study investigated the role of the RASGRP1-S100A9-NLRP3 signaling axis in the cardioprotective effects of S1P. Transcriptomic and single-cell RNA-sequencing analyses were used to identify inflammation…

Sphingosine-1-phosphate receptor 1 signaling stimulates human pluripotent stem cell-derived cardiomyocyte differentiation and maturation.

The development of human-relevant in vitro cardiac models is essential for evaluating cardiotoxicity and drug efficacy. Although wingless-re … ue. Although fetal bovine serum enhanced differentiation, we disclosed that the interaction between sphingosine-1-phosphate (S1P) and its receptor S1PR1 is a major contributor. Gene-based and protein-based analyses and electrophysiological analysis via multielectrode array confirmed that activation of S1PR1 using S1P or its agonist SEW2871 increased the gener …

Fungal Infections Associated with Sphingosine 1-Phosphate Receptor Modulators: Immunological Mechanisms, Clinical Patterns, and Management Considerations.

Fungal infections constitute a large portion of serious infections worldwide and are increasing, partially due to new immunomodulatory therapies, such as Sphingosine-1-Phosphate (S1P) receptor modulators, including fingolimod for the treatment of multiple sclerosis (MS). Fingolimod antagonizes multiple S1P receptors, including S1PR1, S1PR3, S1PR4, and S1PR5, resulting in immunological alterations that may increase susceptibility to invasive fungal infections (IFIs). Our PubMed-based literature search identified 43 published cases and a 60-patient case series describing invasive fungal infectio…

Sphingosine kinase 2 deficiency impairs VLDL secretion by inhibiting mTORC2 phosphorylation and activating chaperone-mediated autophagy.

Hepatic very low-density lipoprotein (VLDL) is essential for maintaining lipid metabolism in the liver. Sphingosine kinases (SphKs) are essential rate-limiting enzymes that catalyze sphingosine phosphorylation to Sphingosine-1-phosphate (S1P). SphKs exist as two isoforms, SphK1 and SphK2, both highly expressed in the liver. SphK1 plays a critical role in regulating hepatic inflammation and drug metabolism. This study aimed to determine whether SphK2 regulates hepatic lipid metabolism, particularly VLDL secretion. Immunohistochemical staining revealed decreased SphK2 protein levels within regio…

Сравнительная эффективность фумаратов Versus Sphingosine-1-Фосфатных рецепторов для чёрных пациентов с множественным склерозом.

ВВЕДЕНИЕ: Множественный склероз (МС) является разнородным заболеванием, которое в непропорционально большой степени затрагивает чернокожих людей с МУ (МСУ), которые страдают более серьезными заболеваниями и более высокими показателями рецидива по сравнению с нечерными группами населения. Несмотря на широко распространенное использование фумаратов и фингосина-1-фосфата (S1P) в качестве рецепторных модуляторов перорально-модифицированных заболеваний (ДМТ) для повторного применения МУ, их сравнительная эффективность в Чёрном PwMS не изучалась. Цель этого исследования состоит в том, чтобы помочь у

Совпадение в аннотации оригинала
INTRODUCTION: Multiple sclerosis (MS) is a heterogeneous disease that disproportionately impacts Black people with MS (PwMS), who experience more severe disease and higher relapse rates compared with non-Black populations. Despite widespread use of fumarates and sphingosine-1-phosphate (S1P) receptor modulators as oral disease-modifying therapies (DMTs) for …

Sphingosine-1-phosphate receptor 3 activation promotes sociability and regulates transcripts important for anxiolytic-like behavior.

We previously demonstrated that sphingosine-1-phosphate receptor 3 (S1PR3) in the medial prefrontal cortex (mPFC) prevents reductions in sociability normally caused by stress. S1PR3 is a ubiquitously expressed G-protein coupled receptor that regulates immune system function, although its regulation of other biological processes is not well understood. Pharmacological activators of S1PR3 might provide important insights for understanding the neural substrates underlying sociability. Here we show that in mice, systemic injections of an S1PR3-specific agonist, CYM5541, promotes sociability in mal…

Mocravimod, a Selective Sphingosine-1-Phosphate Receptor Modulator, in Allogeneic Hematopoietic Stem Cell Transplantation for Malignancy.

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains the sole curative option for patients with acute myelogenous leukemia. Outcomes are limited by leukemia relapse, graft-versus-host disease (GVHD), and abnormal immune reconstitution. Mocravimod (KRP203) is an oral sphingosine-1-phosphate receptor (S1PR) modulator that blocks the signal required by T cells to egress from lymph nodes and other lymphoid organs. Mocravimod retains T cell effector function, a main differentiator to immunosuppressants. In preclinical models, mocravimod improves survival by maintaining graft-versu…

Macrophage Sphingosine 1-Phosphate Receptor 2 Blockade Attenuates Liver Inflammation and Fibrogenesis Triggered by NLRP3 Inflammasome.

NLR family pyrin domain containing 3 (NLRP3) inflammasome accompanies chronic liver injury and is a critical mediator of inflammation-driven liver fibrosis. Sphingosine 1-phosphate (S1P)/S1P Receptor (S1PR) signaling participates in liver fibrogenesis by affecting bone marrow (BM)-derived monocytes/macrophage (BMM) activation. However, the relationship between S1P/S1PR signaling and NLRP3 inflammasome in BMMs remains unclear. Here, we found significantly elevated gene expression of NLRP3 inflammasome components (NLRP3, pro-interleukin-1β, and pro-interleukin-18) and the activation of NLRP3 inf…

Targeting Sphingosine Kinase Isoforms Effectively Reduces Growth and Survival of Neoplastic Mast Cells With D816V-KIT.

Mastocytosis is a disorder resulting from an abnormal mast cell (MC) accumulation in tissues that is often associated with the D816V mutation in KIT, the tyrosine kinase receptor for stem cell factor. Therapies available to treat aggressive presentations of mastocytosis are limited, thus exploration of novel pharmacological targets that reduce MC burden is desirable. Since increased generation of the lipid mediator sphingosine-1-phosphate (S1P) by sphingosine kinase (SPHK) has been linked to oncogenesis, we studied the involvement of the two SPHK isoforms (SPHK1 and SPHK2) in the regulation of…

Sphingosine-1-phosphate ameliorates the cardiac hypertrophic response through inhibiting the activity of histone deacetylase-2.

Inhibition of histone deacetylase-2 (HDAC2), which is a prohypertrophic factor in the heart, can functionally attenuate cardiac hypertrophy. The present study aimed to investigate whether sphingosine‑1‑phosphate (S1P), which has recently been reported to suppress HDAC2 activity, could ameliorate the cardiac hypertrophic response and improve cardiac function in mice with transverse aortic constriction (TAC), as well as to determine the underlying mechanisms. Briefly, 8‑week‑old male C57BL/6 mice were randomly divided into sham, TAC and TAC + S1P groups; the results indicated that S1P treatment …

Vascular transcriptome profiling identifies Sphingosine kinase 1 as a modulator of angiotensin II-induced vascular dysfunction.

Vascular dysfunction is an important phenomenon in hypertension. We hypothesized that angiotensin II (AngII) affects transcriptome in the vasculature in a region-specific manner, which may help to identify genes related to vascular dysfunction in AngII-induced hypertension. Mesenteric artery and aortic transcriptome was profiled using Illumina WG-6v2.0 chip in control and AngII infused (490 ng/kg/min) hypertensive mice. Gene set enrichment and leading edge analyses identified Sphingosine kinase 1 (Sphk1) in the highest number of pathways affected by AngII. Sphk1 mRNA, protein and activity were…

Structural and Functional Insight of Sphingosine 1-Phosphate-Mediated Pathogenic Metabolic Reprogramming in Sickle Cell Disease.

Elevated sphingosine 1-phosphate (S1P) is detrimental in Sickle Cell Disease (SCD), but the mechanistic basis remains obscure. Here, we report that increased erythrocyte S1P binds to deoxygenated sickle Hb (deoxyHbS), facilitates deoxyHbS anchoring to the membrane, induces release of membrane-bound glycolytic enzymes and in turn switches glucose flux towards glycolysis relative to the pentose phosphate pathway (PPP). Suppressed PPP causes compromised glutathione homeostasis and increased oxidative stress, while enhanced glycolysis induces production of 2,3-bisphosphoglycerate (2,3-BPG) and thu…

Sphingosine 1-phosphate receptor 1 is required for retinal ganglion cell survival after optic nerve trauma.

In this study, we used a classical optic nerve injury model to address the function of the sphingosine 1-phosphate (S1P)-S1P receptor (S1PR) axis in retinal ganglion cell (RGC) death and axonal growth. After lesion, the expression of S1PR1 was generally reduced in axotomized RGCs but persisted in αRGCs, a subpopulation of injury-resistant RGCs. Silencing S1PR1 with an adeno-associated virus serotype 2 (AAV2) containing a shRNA specific to S1PR1 (AAV2.shRNA-S1PR1) exacerbated the loss of RGCs induced by optic nerve crush; the rate of RGC survival was decreased by more than 24% in retinae infect…

Identification of Tricyclic Agonists of Sphingosine-1-phosphate Receptor 1 (S1P1) Employing Ligand-Based Drug Design.

Fingolimod (1) is the first approved oral therapy for the treatment of relapsing remitting multiple sclerosis. While the phosphorylated metabolite of fingolimod was found to be a nonselective S1P receptor agonist, agonism specifically of S1P1 is responsible for the peripheral blood lymphopenia believed to be key to its efficacy. Identification of modulators that maintain activity on S1P1 while sparing activity on other S1P receptors could offer equivalent efficacy with reduced liabilities. We disclose in this paper a ligand-based drug design approach that led to the discovery of a series of po

Elevated adenosine signaling via adenosine A2B receptor induces normal and sickle erythrocyte sphingosine kinase 1 activity.

Erythrocyte possesses high sphingosine kinase 1 (SphK1) activity and is the major cell type supplying plasma sphingosine-1-phosphate, a signaling lipid regulating multiple physiological and pathological functions. Recent studies revealed that erythrocyte SphK1 activity is upregulated in sickle cell disease (SCD) and contributes to sickling and disease progression. However, how erythrocyte SphK1 activity is regulated remains unknown. Here we report that adenosine induces SphK1 activity in human and mouse sickle and normal erythrocytes in vitro. Next, using 4 adenosine receptor-deficient mice an…

Sphingosine 1-phosphate receptor type 1 regulates egress of mature T cells from mouse bone marrow.

Sphingosine 1-phosphate (S1P) and its receptor, S1P receptor type 1 (S1P(1)), are essential for lymphocyte egress from secondary lymphoid organs (SLO). Fingolimod (FTY720), the S1P receptor modulator, inhibits lymphocyte egress from SLO and decreases circulating lymphocytes; however, it also induces a significant decrease in the number of peripheral blood lymphocytes in alymphoplasia (aly/aly) mice lacking SLO. In this study, we demonstrated that the administration of FTY720 induced sequestration of mature lymphocytes, particularly T cells, into the bone marrow (BM) in aly/aly mice, implying t…

1Alpha,25-dihydroxyvitamin D3 protects human keratinocytes from apoptosis by the formation of sphingosine-1-phosphate.

Owing to its ability to induce growth arrest and differentiation of keratinocytes, 1alpha,25-dihydroxyvitamin D3 and its analogs are useful … a. The cytoprotective effect was accompanied by the formation of the sphingolipid breakdown product sphingosine-1-phosphate, which prevented apoptosis in analogy to 1alpha,25-dihydroxyvitamin D3. The effect of 1alpha,25-dihydroxyvitamin D3 was specific as the almost inactive precursor cholecalciferol neither induced sphingosine-1-phosphate formation nor preve …