SB505124

ALK

335, 4

New Zealand White (NZW) rabbits after glaucoma filtration surgery (GFS).

0-10 uM

Tablets containing 5 mg of SB505124 and 65 mg lactose (6 mm in diameter, 1.0 mm in thickness) are prepared using a compression technique.

SB505124 is identified as a reversible ATP competitive and selective ALK inhibitor of ALK4 and ALK5. SB505124 shows no toxicity to renal epithelial A498 cells at concentrations up to 100 uM for 48 hours, and blocks TGF-beta–induced apoptosis of FaO cells and NRP 154 cells in a concentration-dependent manner. [1] In human umbilical vein endothelial cells (HUVEC), SB505124 (500 nM) blocks the changes of TGF-beta1 on F-actin assembly and prevents ROS production induced by TGF-beta. [2] By inhibiting TGF-beta1 signaling, SB505124 leads to decreased deferoxamine (DFO)-induced neurogenesis. [3] A recent study shows that SB505124 suppresses the migration and invasion of breast cancer MCF-7-M5 cells. [4]

48 hours

Cell viability is measured as described by Laping et al., 2002 or by using the modified tetrazolium salt WST-1. XTT assay: The cells are serum-deprived for 24 hours and then treated with SB505124 for 48 hours to assess the cellular toxicity. Cell viability is determined by incubating cells for 4 hours with XTT labeling and electron coupling reagent according to the manufacturer's directions. Live cells with active mitochondria produce an orange-colored product, formazan, which is detected using a plate reader at between A450 nm and A500 nm with a reference wavelength greater than 600 nm. The absorbance values correlate with the number of viable cells. Modified tetrazolium salt WST-1: Approximately 2000 cells are seeded in 96-well dishes in 100 uL of 0.2% FBS phenol red-free media overnight. The cells are treated with 50 uL of SB505124 (to achieve the final concentrations indicated) for 30 minutes before being treated with or without TGF-beta1 and TNF-alpha to a final volume of 200 uL. Cell growth is measured at the indicated time points by incubating each well with 10 uL of WST-1 for 3 hours at 37 C. Metabolically active cells cleave WST-1 to water-soluble formazan, which is directly quantitated with an enzyme-linked immunosorbent assay plate reader. Each experiment is done at least twice, and treatment for each cell line was done in triplicate.

SB505124 is a selective inhibitor of TGFβR for ALK4, ALK5 with IC50 of 129 nM and 47 nM in cell-free assays, respectively, also inhibits ALK7, but does not inhibit ALK1, 2, 3, or 6.