NQDI-1 

Enzyme activity of human protein kinases ASK1, Aurora A, ROCK1, HGFR, FGFR1, Tie2, JNK3, and CK2 is determined using in vitro kinase assay (γ-³²P-ATP method). Each reaction mixture contains 6 μL of buffer solution (25 mM MOPS, pH 7.2, 2.5 mM EGTA, 2.5 mM EDTA, 0.5 mM DTT, 0.25 mg/mL BSA, 20 mM β-glycerophosphate), 3 μL of substrate solution (MBP, Long S6 kinase substrate peptide, KKKSPGEYVNIEFG, IGF-IRtide (12-527), TK substrate 2, JNK3tide, or RRRDDDSDDD for each kinase, respectively) (5.0 μg/μL), 0.3 μL of enzyme (protein kinase catalytic subunit, 0.1 μg/μL≈32 mU/μL), and 10.25 μL of H₂O. The reaction mixture (total volume of 19 μL) is quickly added to 1.5 mL tubes at room temperature. The stock solutions of inhibitors (e.g., NQDI-1) are prepared in DMSO, and the concentration of inhibitor is 1 mM. The concentration of DMSO in the reaction does not exceed 3%. Then 1 μL of inhibitor solution in DMSO is added to each tube and mixed by pipetting. ATP solution is prepared separately. For each sample 0.05 mCi γ-[P³²]ATP is taken (specific activity of 100 μCi/μM). The total concentration of labeled and unlabeled ATP is 100 μM. The reaction is started with addition of ATP solution (150 μM ATP, 30 mM MgCl₂, 15 mM MOPS, pH 7.2). The time of reaction is 20 min at 30°C. The reaction is stopped by adding 20 μL of 0.5 M orthophosphoric acid. Then the reaction mixture is loaded on the 20 mm filter disks of the cellulose phosphate paper. Filters are washed three times with 0.075 M orthophosphoric acid at room temperature and dried. For detection of products, dried filters are counted by Tri-Carb 2800-TR liquid scintillation analyzer. Then 1 μL of DMSO is added to the reaction volume instead of the inhibitor stock solution for a positive control^[1].

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

Rats^[2]
A total of 12 female Sprague-Dawley rats with litters of mixed gender pups are used. The mothers are housed at 25°C under a 12-h light/dark cycle, with ad libitum access to food and water, until the pups are 7-days-old. The HI model is established. The pups are anesthetized with 2.5% halothane and are intracerebroventricularly infused with DMSO or 250 nmol NQDI-1, dissolved in DMSO into the right cerebral hemisphere 30 min prior to HI using a 30-gauge needle with a 5 μL Hamilton syringe (infusion rate, 1 μL/min).

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

• [1]. Volynets GP, et al. Identification of 3H-naphtho[1,2,3-de]quinoline-2,7-diones as inhibitors of apoptosis signal-regulating kinase 1 (ASK1). J Med Chem. 2011 Apr 28;54(8):2680-6.  [Content Brief]

  [2]. Hao H, et al. NQDI-1, an inhibitor of ASK1 attenuates acute perinatal hypoxic-ischemic cerebral injury by modulating cell death. Mol Med Rep. 2016 Jun;13(6):4585-92.  [Content Brief]