10Z-Hymenialdisine is a natural marine sponge alkaloid with numerous cellular actions. Most notably, it blocks signaling through the Raf-1/MEK-1/MAPK pathway by potently inhibiting MEK-1 (IC50 = 9 nM). Hymenialdisine also inhibits numerous kinases in vitro, most notably GSK3β, CDK1/cyclin B, CDK5/p25, CK1, and CDK2/cyclin E (IC50s = 10, 22, 28, 35, and 40 nM, respectively), as well as, less potently, ERK1/2 and several isoforms of PKC. Early studies demonstrated that it suppresses inflammatory gene expression by blocking signaling through NF-κB at micromolar concentrations. At similar concentrations, hymenialdisine also blocks bacterial quorum sensing.
