Myeloperoxidase Inhibitor-II

A 5-fluorotryptamine derivative that inhibitis the MPO-catalyzed Cl^-/chloride-to-OCl^-/hypochlorite oxidation in the presence of H²O² (IC₅₀ = 18 nM by taurine/2-aminoethan-sulfonic acid chlorination assay) as well as MPO-mediated LDL ApoB-100 (ApoB100; apolipoprotein B-100) oxidation (IC₅₀ = 18 nM by ELISA) via direct affinity binding at the myeloperoxidase active site through ϖ-ϖ interaction between its indole and the the enzyme′s heme pyrrole ring D, while exhibiting much reduced affinity toward serotonin reuptake transporter/SERT (K_i = 631 nM). Kinetic studies reveal that the inhibitor acts as a good one-electron donor for the intermediate Compound I "Fe(IV)=O...Por^•+", facilitating the formation (k₃ = 1,6 x 10⁷ M^-1 s^-1) of Compound II (Fe(IV)-OH...Por) and thereby preventing the reduction of Compound I directly to the resting state "Fe(IV)...Por" via the "halogenation cycle", while, on the other hand, behaves as a poor electron donor for Compound II, thereby preventing the completion of the "peroxidase cycle" by stalling the further reduction of Compound II to the resting state (k₄ = 92 M^-1 s^-1). Toxicology study using Wistar Han male rats reports no signs of adverse effects post single 10 mg/kg i.p. dosage, while signs of adverse effects are observed within the 24 h, but not after, post a higher i.p. dosage at 100 mg/kg.

Cell permeable: yes

Primary Target
myeloperoxidase

Reversible: yes

Packaged under inert gas

Toxicity: Standard Handling (A)

Following reconstitution, aliquot and freeze (-20°C). Stock solutions are stable for up to 6 months at -20°C.

Use only fresh DMSO for reconstitution.

Soubhye, J., et al. 2013. J. Med. Chem.56, 3943.
Soubhye, J., et al. 2010. J. Med. Chem.53, 8747.

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