Identification of multi-target inhibitors of leukotriene and prostaglandin E2 biosynthesis by structural tuning of the FLAP inhibitor BRP-7

Abstract

Leukotrienes (LTs) and prostaglandin (PG)E₂ are enzymatically produced from arachidonic acid and represent highly bioactive lipid mediators with pro-inflammatory functions. Here, we report on novel multi-target inhibitors that potently and dually interfere with 5-lipoxygenase-activating protein (FLAP) and microsomal prostaglandin E₂ synthase (mPGES)-1 in LT and PGE₂ biosynthesis, based on the previously identified selective FLAP inhibitor BRP-7 (8, IC₅₀ = 0.31 μM). C (5)-substitution of the benzimidazole ring of BRP-7 by carboxylic acid and its bioisosteres provided compounds, exemplified by 57 that potently suppress LT formation (IC₅₀ = 0.05 μM) by targeting FLAP along with inhibition of mPGES-1 (IC₅₀ = 0.42 μM). Besides FLAP, also 5-lipoxygenase (5-LO) and LTC₄ synthase activities were inhibited by 57, albeit with lower potency (IC₅₀ = 0.6 and 6.2 μM) than FLAP. Docking studies and molecular dynamic simulations with FLAP, mPGES-1 and 5-LO provide valuable insights into potential binding interactions of the inhibitors with their targets. Together, these novel benzimidazole derivatives may possess potential as leads for development of effective anti-inflammatory drugs with multi-target properties for dually inhibiting LT and PGE₂ production.

Keywords: 5-Lipoxygenase; 5-Lipoxygenase-activating protein; Benzimidazole; Inflammation; Leukotriene; Microsomal prostaglandin E(2) synthase-1.