DL-TBOA

DL-TBOA is a potent non-transportable inhibitor of excitatory amino acid transporters with IC50s of 70 μM, 6 μM and 6 μM for excitatory amino acid transporter-1 (EAAT1), EAAT2 and EAAT3, respectively. DL-TBOA inhibits the uptake of [14C]glutamate in COS-1 cells expressing the human EAAT1 and EAAT2 with Ki valuesof 42 μM and 5.7 μM, respectively. DL-TBOA blocks EAAT4 and EAAT5 in a competitive manner with Ki values of 4.4 μM and 3.2 μM, respectively[1][2][3].

Signaling Pathways >> Membrane Transporter/Ion Channel >> EAAT2

IC50: 70 μM (EAAT1), 6 μM (EAAT2) and 6 μM (EAAT3); Ki: 42 μM (human EAAT1), 5.7 μM (human EAAT2), 4.4 μM (EAAT4) and 3.2 μM (EAAT5)[1][2][3]

DL-TBOA (70-350 μM; 48 hours; HCT116 and LoVo cell lines) treatment concentration-dependently enhances SN38-induced loss of viability. DL-TBOA reversed Oxaliplatin-induced loss of viability[4]. DL-TBOA (350 μM; 24 hours; HCT116 and LoVo cell lines) treatment decreases p53 induction by SN38 and oxaliplatin[4]. Cell Viability Assay[4] Cell Line: HCT116 and LoVo cell lines Concentration: 70 μM or 350 μM Incubation Time: 48 hours Result: Enhanced SN38-induced, and counteracted Oxaliplatin-induced, cell death. Cell Viability Assay[4] Cell Line: HCT116 and LoVo cell lines Concentration: 350 μM Incubation Time: 24 hours Result: p53 induction by SN38 and oxaliplatin was decreased.

[1]. Shimamoto K, et al. DL-threo-beta-benzyloxyaspartate, a potent blocker of excitatory amino acid transporters. Mol Pharmacol. 1998 Feb;53(2):195-201.

[2]. Jabaudon D, et al. Inhibition of uptake unmasks rapid extracellular turnover of glutamate of nonvesicular origin. Proc Natl Acad Sci U S A. 1999 Jul 20;96(15):8733-8.

[3]. Shigeri Y, et al. Effects of threo-beta-hydroxyaspartate derivatives on excitatory amino acid transporters (EAAT4 and EAAT5). J Neurochem. 2001 Oct;79(2):297-302.

[4]. Pedraz-Cuesta E, et al. The glutamate transport inhibitor DL-Threo-β-Benzyloxyaspartic acid (DL-TBOA) differentially affects SN38- and oxaliplatin-induced death of drug-resistant colorectal cancer cells. BMC Cancer. 2015 May 16;15:411.