• 대한약리학회:학술대회논문집
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• 2006.10a
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• pp.105.1-105.1
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• 2006

• Biomolecules & Therapeutics
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• v.29 no.1
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• pp.52-57
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• 2021

Fumonisin B1 (FB1) structurally resembles sphingolipids and interferes with their metabolism leading to sphingolipid dysregulation. We questioned if FB1 could exacerbate liver or kidney toxicities in glutathione peroxidase 1 (Gpx1) and catalase (Cat) knockout mice. While higher serum levels of thiobarbituric acid reactive substances (TBARS) and sphinganine (Sa) were measured in Gpx1/Cat knockout mice (Gpx1/Cat KO) than wild type mice after 5 days of FB1 treatment, serum levels of alanine aminotransferase (ALT), sphingosine-1 phosphate (So-1-P), and sphinganine-1 phosphate (Sa-1-P) were found to be relatively low. Although Sa was highly elevated in Gpx1/Cat KO mice and wild mice, lower levels of So and Sa were found in both the kidney and liver tissues of Gpx/Cat KO mice than wild type mice after FB1 treatment. Paradoxically, FB1-induced cellular apoptosis and necrosis were hastened under oxidative stress in Gpx1/Cat KO mice.

• Biomolecules & Therapeutics
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• v.27 no.4
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• pp.373-380
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• 2019

Sphingosine kinase 1 and its product, sphingosine 1-phosphate (S1P), as well as their receptors, have been implicated in inflammatory responses. The functions of receptors $S1P_1$ and $S1P_2$ on cell motility have been investigated. However, the function of $S1P_3$ has been poorly investigated. In this study, the roles of $S1P_3$ on inflammatory response were investigated in primary peritoneal macrophages. $S1P_3$ receptor was induced along with sphingosine kinase 1 by stimulation of lipopolysaccharide (LPS). LPS treatment induced inflammatory genes, such iNOS, COX-2, $IL-1{\beta}$, IL-6 and $TNF-{\alpha}$. TY52156, an antagonist of $S1P_3$ suppressed the induction of inflammatory genes in a concentration dependent manner. Suppression of iNOS and COX-2 induction was further confirmed by western blotting and NO measurement. Suppression of $IL-1{\beta}$ induction was also confirmed by western blotting and ELISA. Caspase 1, which is responsible for $IL-1{\beta}$ production, was similarly induced by LPS and suppressed by TY52156. Therefore, we have shown $S1P_3$ induction in the inflammatory conditions and its pro-inflammatory roles. Targeting $S1P_3$ might be a strategy for regulating inflammatory diseases.

• Biomolecules & Therapeutics
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• v.28 no.6
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• pp.537-541
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• 2020

Sphingosine-1-phosphate (S1P) and its receptors have been implicated in atopic dermatitis. S1P₂ was found to function as a proallergic receptor, while its antagonist JTE-013 was found to suppress allergic asthma in mice. Topical application of JTE-013 has not been investigated in an in vivo model of atopic dermatitis. Therefore, the therapeutic potential of JTE-013 topical application was evaluated by the use of a 2,4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis mouse model. DNCB-induced inflammation and mast cell accumulation in skin tissues were significantly suppressed by topical JTE-013 treatment in BALB/c mice. DNCB-induced increase of lymph nodes sizes and elevated inflammatory cytokines (IL-4, IL-13, IL-17, and IFN-γ) in lymph nodes were also significantly reduced by the JTE-013 treatment. Elevated serum levels of IgE were significantly suppressed by the topical treatment of JTE-013. In summary, the topical treatment of JTE-013 S1P₂ antagonist suppressed DNCB-induced atopic dermatitis symptoms and immune responses. These results suggested JTE-013 as a potential therapeutic agent for atopic dermatitis.

• Journal of Life Science
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• v.21 no.2
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• pp.183-193
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• 2011

Migration and differentiation of mesenchymal stem cells are crucial for tissue regeneration in response to injury. Sphingosine-1-phosphate (S1P) is a bioactive lipid that regulates a variety of biological processes, including proliferation, survival, differentiation and motility. In the present study, we determined the role of S1P in migration and differentiation of human bone marrow-derived mesenchymal stem cells (BMSCs). S1P stimulated migration of BMSCs in a dose- and time-dependent manner, and pre-incubation of the cells with pertussis toxin completely abrogated S1P-induced migration, suggesting involvement of Gi-coupled receptors in S1P-induced cell migration. S1P elicited elevation of intracellular concentration of $Ca^{2+}$ ($[Ca^{2+}]_i$) and pretreatment with VPC23019, an antagonist of $S1P_1/S1P_3$, blocked S1P-induced migration and increase of $[Ca^{2+}]_i$. Small interfering RNA-mediated knockdown of endogenous $S1P_1$ attenuated S1P-induced migration of BMSCs. Furthermore, S1P treatment induced expression of $\alpha$-smooth muscle actin ($\alpha$-SMA), a smooth muscle marker, and pretreatment with VPC23019 abrogated S1P-induced $\alpha$-SMA expression. S1P induced phosphorylation of p38 mitogen-activated protein kinase (MAPK), and pretreatment of cells with SB202190, an inhibitor of p38 MAPK, or adenoviral overexpression of a dominant-negative mutant of the p38 MAPK blocked S1P-induced cell migration and $\alpha$-SMA expression. Taken together, these results suggest that S1P stimulates migration and smooth muscle differentiation of BMSCs through an $S1P_1$-p38 MAPK-dependent mechanism.

• Proceedings of the KSAR Conference
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• 2002.06a
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• pp.70-70
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• 2002

Sphingosine-1-phosphate(S1P) is one of the sphingolipid metabolites which affect a variety of cellular processes including the proliferation, differentiation, growth, survival, migration and gene expression. The present study was undertaken to investigate the effect of SIP on nuclear maturation of porcine oocytes. In vitro maturation frequency of porcine oocytes were compared in three different media; group Ⅰ: NCSU23＋0.1% PVA, group Ⅱ: NCSU23＋10% PFF(porcine follicular fluid), and group Ⅲ: NCSU23＋10% PFF＋10 ng/㎖ EGF＋2.5 mM β-mercaptoethanol. Each group containing 0.1 ㎎/㎖ cysteine was divided into 4 sub-groups of SIP concentration(0, 50, 500 and 5000nM). Porcine oocytes were incubated in each maturation medium supplemented with hormones(10 IU/㎖ PMSG and 10 IU/㎖ hCG) for 22h and then further cultured in the same medium without the hormones for 22h. After completion of in vitro maturation, the oocytes were fixed and stained to examine nuclear maturation by using a rapid stain method. In the group Ⅰ, the proportions of metaphase Ⅱ stage among oocytes cultured in 0nM(control), 50 nM, 500nM and 5000nM S1P were 45.5%, 66.7%, 56.6% and 48.7%, respectively. (omitted)

• Biomolecules & Therapeutics
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• v.26 no.6
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• pp.546-552
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• 2018

A comprehensive collection of proteins senses local changes in intracellular $Ca^{2+}$ concentrations ($[Ca^{2+}]_i$) and transduces these signals into responses to agonists. In the present study, we examined the effect of sphingosine-1-phosphate (S1P) on modulation of intracellular $Ca^{2+}$ concentrations in cat esophageal smooth muscle cells. To measure $[Ca^{2+}]_i$ levels in cat esophageal smooth muscle cells, we used a fluorescence microscopy with the Fura-2 loading method. S1P produced a concentration-dependent increase in $[Ca^{2+}]_i$ in the cells. Pretreatment with EGTA, an extracellular $Ca^{2+}$ chelator, decreased the S1P-induced increase in $[Ca^{2+}]_i$, and an L-type $Ca^{2+}$-channel blocker, nimodipine, decreased the effect of S1P. This indicates that $Ca^{2+}$ influx may be required for muscle contraction by S1P. When stimulated with thapsigargin, an intracellular calcium chelator, or 2-Aminoethoxydiphenyl borate (2-APB), an $InsP_3$ receptor blocker, the S1P-evoked increase in $[Ca^{2+}]_i$ was significantly decreased. Treatment with pertussis toxin (PTX), an inhibitor of $G_i$-protein, suppressed the increase in $[Ca^{2+}]_i$ evoked by S1P. These results suggest that the S1P-induced increase in $[Ca^{2+}]_i$ in cat esophageal smooth muscle cells occurs upon the activation of phospholipase C and subsequent release of $Ca^{2+}$ from the $InsP_3$-sensitive $Ca^{2+}$ pool in the sarcoplasmic reticulum. These results suggest that S1P utilized extracellular $Ca^{2+}$ via the L type $Ca^{2+}$ channel, which was dependent on activation of the $S1P_4$ receptor coupled to PTX-sensitive $G_i$ protein, via phospholipase C-mediated $Ca^{2+}$ release from the $InsP_3$-sensitive $Ca^{2+}$ pool in cat esophageal smooth muscle cells.

• Journal of Nutrition and Health
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• v.45 no.2
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• pp.113-120
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• 2012

In our previous studies, dietary supplements of silk protein, sericin, and fibroin, were beneficial for improving epidermal levels of ceramides, which are the major lipids for maintaining the epidermal barrier. In this study, we investigated the dietary effects of silk protein on epidermal levels of free sphingoid bases and their phosphates such as $C_{18}$ sphingosine (So), $C_{18}$ sphinganine (Sa), $C_{18}$ sphingosine-1-phosphate (S1P), and $C_{18}$ sphinganine-1-phosphate (Sa1P), which are either synthetic substrate or degradative metabolites of ceramides. Forty-five male NC/Nga mice, an animal model of atopic dermatitis (AD), were divided into three groups: group CA was an atopic control and fed a control diet, group S was fed a 1% sericin diet, and group F was fed a 1% fibroin diet. Fifteen male BALB/c mice served as group C (control group) and were fed the control diet. All mice were fed with diets and water $ad$ $libitum$ for 10 weeks. Sa in group CA was lower than that in group C, but So in group CA was similar to that in group C. So and Sa were higher in groups S and F than those in group CA; So level was even higher than that in group C, and Sa level was similar to that of group C. The So/Sa ratio in group CA, which is reported to increase in AD, was significantly higher than that of group C. The So/Sa ratio was lower in groups S and F than that in group CA, and decreased further in group F. However, S1P and Sa1P in groups S and F were similar to those in group CA. Taken together, we demonstrated that silk protein, sericin and fibroin dietary supplements, increased So and Sa levels, and decreased the So/Sa ratio.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.96-97
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• 2002

Lysophosphatidic acid (LPA) and sphingosine 1-phosphate (SIP) are bioactive lysophospholipids (LPs) that act as mediators in various cellular processes, such as cell growth, differentiation, survival, motility, and cytoskeletal reorganization (1,2). LPA and S1P are both abundant in serum and are produced by activated platelets and other cell types. (omitted)

• Bulletin of the Korean Chemical Society
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• v.24 no.3
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• pp.267-268
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• 2003