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. 2009 Jan;23(1):143-52.
doi: 10.1096/fj.08-118109. Epub 2008 Sep 24.

A role for sphingosine kinase 1 in dextran sulfate sodium-induced colitis

Ashley J Snider  1 , Toshihiko Kawamori, Sarah G Bradshaw, K Alexa Orr, Gary S Gilkeson, Yusuf A Hannun, Lina M Obeid
Affiliations

A role for sphingosine kinase 1 in dextran sulfate sodium-induced colitis

Ashley J Snider et al. FASEB J. 2009 Jan.

Abstract

The bioactive lipid sphingosine-1-phosphate (S1P) is emerging as an important mediator of immune and inflammatory responses. S1P formation is catalyzed by sphingosine kinase (SK), of which the SK1 isoenzyme is activated by tumor necrosis alpha (TNF-alpha). SK1 has been shown to be required for mediating TNF-alpha inflammatory responses in cells, including induction of cyclooxygenase 2 (COX-2). Because TNF-alpha and COX-2 are increased in patients with inflammatory bowel disease (IBD), we investigated the role of SK1 in a murine model of colitis. SK1(-/-) mice treated with dextran sulfate sodium (DSS) had significantly less blood loss, weight loss, colon shortening, colon histological damage, and splenomegaly than did wild-type (WT) mice. In addition, SK1(-/-) mice had no systemic inflammatory response. Moreover, WT but not SK1(-/-) mice treated with dextran sulfate sodium had significant increases in blood S1P levels, colon SK1 message and activity, and colon neutrophilic infiltrate. Unlike WT mice, SK1(-/-) mice failed to show colonic COX-2 induction despite an exaggerated TNF-alpha response; thus implicating for the first time SK1 in TNF-alpha-mediated COX-2 induction in vivo. Inhibition of SK1 may prove to be a valuable therapeutic target by inhibiting systemic and local inflammation in IBD.

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Figures

Figure 1.
Figure 1.
Immunohistochemistry for SK1 and COX-2 in human colon samples. A, E) Normal mucosa with SK1 (A) and COX-2 staining (E). B–D, F–H) Ulcerative colitis sample with SK1 (B–D) and COX-2 staining (F–H). Scale bars = 50 μm.
Figure 2.
Figure 2.
SK1−/− mice are partially protected against DSS-induced colitis. Tissue sections from WT and SK1−/− mice were H&E stained and graded for colonic damage as described in Materials and Methods. A–C) Representative sections from untreated mice (A), WT mice after 7 days of DSS treatment (B), and SK1−/− mice after 7 days of DSS treatment (C). Arrows indicate areas of inflammatory infiltrate. D) Damage score from WT and SK1−/− mice after 7 days of DSS. Data represent means ± se;n = 2 mice/group for no treatment, 6 mice/group for DSS treatment; ***P < 0.001.
Figure 3.
Figure 3.
Effects of DSS-induced colitis in WT and SK1−/− mice. WT and SK1−/− mice were administered 5% DSS in drinking water for 5 days and disease severity was assessed by weight loss (A), change in colon length (B), and spleen weight (C). Data represent means ± se;n > 10 mice/group; *P < 0.05, **P < 0.01, ***,#P < 0.001.
Figure 4.
Figure 4.
WT mice have significantly fewer circulating RBCs and increased circulating WBCs after DSS administration. Complete blood counts were performed on whole blood from untreated WT and SK1−/− mice, as well as mice after 3 and 5 days of DSS treatment. Blood was analyzed for RBCs (A), WBCs (B), and lymphocytes (C). Data represent means ± se;n = 10 mice/group; *P < 0.05, ***P < 0.001.
Figure 5.
Figure 5.
S1P is elevated in the blood of WT mice. Whole blood was collected with anticoagulant from mice after 5 days of DSS administration. Samples were analyzed for sphingolipid content using HPLC-ESI-MS by the Lipidomics Core Facility at MUSC: S1P (A), sphingosine (B), and total ceramide in whole blood with or without DSS administration (C). Data represent means ± se;n = 5 mice/group; **P < 0.01.
Figure 6.
Figure 6.
SK1 message and activity increase in WT mice with DSS colitis. A) Real-time RT-PCR was performed to determine message levels of SK1 in colon tissue from WT untreated mice and WT mice after 3 and 5 days of DSS treatment, using β-actin as a reference gene. B) SK activity in colon tissue from untreated and DSS-treated WT and SK1−/− mice. Data represent means ± se;n = 5 mice/group; ***P < 0.001.
Figure 7.
Figure 7.
Colons from WT mice have significant granulocytic infiltration after DSS treatment. Colons from untreated and DSS-treated WT and SK1−/− mice were homogenized and stained for granulocyte marker, GR1. Flow cytometry was used for detection of granulocytes. Data represent means ± se;n = 5 mice/group; ***P < 0.001.
Figure 8.
Figure 8.
COX-2 induction, but not TNF-α, is prevented in SK1−/− mice administered DSS. Colon tissue was harvested from untreated WT and SK1−/− mice and mice treated with DSS for 3 and 5 days; mRNA was extracted and reverse transcribed into cDNA. Real-time RT-PCR was performed to determine relative levels of TNF-α (A) and COX-2 (B); β-actin was used as a reference gene. Data represent means ± se;n = 5–10 mice/group; *P < 0.05, ***P < 0.001.
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References

    1. Obeid L M, Linardic C M, Karolak L A, Hannun Y A. Programmed cell death induced by ceramide. Science (New York) 1993;259:1769–1771. - PubMed
    1. Venable M E, Lee J Y, Smyth M J, Bielawska A, Obeid L M. Role of ceramide in cellular senescence. J Biol Chem. 1995;270:30701–30708. - PubMed
    1. Seufferlein T, Rozengurt E. Sphingosine induces p125FAK and paxillin tyrosine phosphorylation, actin stress fiber formation, and focal contact assembly in Swiss 3T3 cells. J Biol Chem. 1994;269:27610–27617. - PubMed
    1. Lee S C, Kuan C Y, Wen Z D, Yang S D. The naturally occurring PKC inhibitor sphingosine and tumor promoter phorbol ester potentially induce tyrosine phosphorylation/activation of oncogenic proline-directed protein kinase FA/GSK-3alpha in a common signalling pathway. J Protein Chem. 1998;17:15–27. - PubMed
    1. Kimura T, Watanabe T, Sato K, Kon J, Tomura H, Tamama K, Kuwabara A, Kanda T, Kobayashi I, Ohta H, Ui M, Okajima F. Sphingosine 1-phosphate stimulates proliferation and migration of human endothelial cells possibly through the lipid receptors, Edg-1 and Edg-3. Biochem J. 2000;348:71–76. - PMC - PubMed

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