Vadimezan (DMXAA)

Chemical carcinogen (NMU) is injected into female Wistar rats.

2-(5, 6-dimethyl-9-oxo-9H-xanthen-4-yl)acetic acid

0-2 mM

<=300 mg/kg

62.5 uM, 62.5 uM, 62.5 uM, 62.5 uM, 62.5 uM, 62.5 uM

DMXAA treatment significantly protects C57BL/6J mice infected i.n. with 200 p.f.u. mouse-adapted H1N1 influenza PR8 virus with 60% survival, while the control group only exhibited 20% survival. [2] DMXAA significantly delays tumor growth induced by chemical carcinogen, increases the time to tumor doubling and increases time from treatment to euthanasia. After the treatment of DMXAA, median tumor doubling time, median tumour tripling time and median time from treatment to euthanasia in tumor-bearing animals are increased by approximately 4.4-, 1.8- and 2.7-fold, respectively. [4]

DT-diaphorase activity and kinetic analysis of enzyme inhibition, Purified DT-diaphorase enzyme activity is assayed by measuring the reduction of cytochrome c at 550 nm on a Beckman DU 650 spectrophotometer. Each assay contains cytochrome c (70 uM), NADH (variable concentrations), purified DT-diaphorase (0.032 ug), and menadione (variable concentrations) in a final volume of 1 mL Tris–HCl buffer (50 mM, pH 7.4) containing 0.14% BSA. The reaction is started by the addition of NADH. Rates of reduction are calculated over the initial part of the reaction curve (30 seconds), and results are expressed in terms of umol cytochrome c reduced/min/mg protein using a molar extinction coefficient of 21.1 mM 1 cm 1 for reduced cytochrome c. Enzyme assays are carried out at room temperature and all reactions are performed in triplicate. Inhibition of purified DT-diaphorase activity is performed by the inclusion of DMXAA (at various concentrations) in the reaction, and inhibition characteristics are determined by varyinthe concentration of NADH (constant menadione) or menadione (constant NADH) at several concentrations of inhibitor. Ki values are obtained by plotting 1/V against. The activity of DT-diaphorase in DLD-1 cells is determined by measuring the dicumarol-sensitive reduction of DCPIP at 600 nm. Briefly, DLD-1 cells in mid-exponential growth are harvested by scraping into ice-cold buffer (Tris–HCl, 25 mM, pH 7.4 and 250 mM sucrose) and sonicated on ice. Enzyme assay conditions are 2 mM NADH, 40 uM DCPIP, 20 uL of dicumarol (when required) in a final volume of 1 mL Tris–HCl (25 mM, pH 7.4) containing BSA (0.7 mg/mL). Results are expressed as the dicumarol-sensitive reduction of DCPIP using a molar extinction coefficient of 21 mM 1 cm 1. Protein levels are determined using the Bradford assay

282, 29

DMSO 7 mg/mL, Water <1 mg/mL, Ethanol <1 mg/mL