| Description: |
SC-560 is a potent and selective COX-1 inhibitor with an IC50 of 9 nM. |
| Target: |
COX-1:9 nM (IC50)
COX-2:6.3 μM (IC50) |
| In Vivo: |
Oral dosing with either 10 or 30 mg/kg SC-560 1 hour before assay completely inhibits ionophore-stimulated TxB2production, indicating that SC-560 is orally bioavailable and inhibits COX-1 in vivo[1]. SC-560 extensively distributes into rat tissues, and has a CL approaching hepatic plasma flow. The drug displays low less than 15% and formulation dependent bioavailability after oral administration and demonstrates kidney toxicity[3]. |
| In Vitro: |
Preincubation of COX-1 with SC-560 inhibits the conversion of arachidonic acid to PGE2 in a concentration-dependent manner. The IC50 of SC-560 for COX-2 is 6.3 μM, nearly 1,000-fold higher than with COX-1[1]. SC-560 shows a dose and time dependent inhibitory effect on HCC cell growth. SC-560 also inhibits colony formation in soft agar and induces apoptosis in HCC cells in a dose-dependent manner. Moreover, SC-560 decreases the levels of the anti-apoptotic proteins survivin and XIAP and activates caspase 3 and 7 in a dose and time dependent fashion[2]. |
| Cell Assay: |
HuH-6 and HA22T/VGH cells (5000/well) are treated with various concentrations of SC-560 (5, 10, 25, 50, 100, 200 μM) and cultured for 72 h. At the end of treatment, cell viability is assessed by MTS assay[2]. |
| Animal Administration: |
Rats: The pharmacokinetics of SC-560 is studied in Sprague-Dawley rats after a single intravenous (i.v.) and oral dose (10 mg/kg) in polyethylene glycol (PEG) 600 and a single oral dose (10 mg/kg) in 1% methylcellulose (MC). Serial blood samples are collected via a catheter inserted in the right jugular vein and serum samples are analysed for SC-560 using reverse phase HPLC. After oral administration of SC-560 in PEG, urine is also collected for 24 h and analyzed for urinary sodium, chloride, and potassium as well as NAG[3]. |
| References: |
[1]. Smith CJ, et al. Pharmacological analysis of cyclooxygenase-1 in inflammation. Proc Natl Acad Sci U S A. 1998 Oct 27;95(22):13313-8.
[2]. Lampiasi N, et al. The selective cyclooxygenase-1 inhibitor SC-560 suppresses cell proliferation and induces apoptosis in human hepatocellular carcinoma cells. Int J Mol Med. 2006 Feb;17(2):245-52.
[3]. Teng XW, et al. Formulation dependent pharmacokinetics, bioavailability and renal toxicity of a selective cyclooxygenase-1 inhibitor SC-560 in the rat. J Pharm Pharm Sci. 2003 May-Aug;6(2):205-10. |
