Cinnamaldehyde and poly‐cinnamaldehyde micelles induce relaxation of isolated porcine coronary arteries

Abstract

Cinnamaldehyde (CA), one of major components of cinnamon, induces the generation of ROS and exerts vasodilator and anticancer effects. However, its short half‐life limits its clinical use. Therefore, a polymeric pro‐drug that incorporates CA in its backbone [poly(cinnamaldehyde) (PCA)] and self assembles to form micelles was developed. Experiments were designed to determine whether or not PCA micelles possess vasodilator properties. Rings of porcine coronary arteries were contracted with U46619 and changes in isometric tension recorded. CA induced endothelium‐independent relaxations that were not affected by catalase or inhibitors of eNOS (L‐NAME), nNOS (SMLT), cyclooxygenases (indomethacin), soluble guanylyl cyclase (ODQ), TRP (ruthenium red) or TRPA1 channels (HC030031). Inhibition of either KATP channels (glibenclamide) or superoxide dismutase (DETC) caused a leftward shift of the concentration‐response curve to CA. PCA micelles induced only partial, endothelium‐dependent relaxations that were inhibited by L‐NAME, SMLT, ODQ, and catalase. The present findings demonstrate that micelles prepared from PCA possess vasodilator properties, but the mechanism underlying relaxation differs from that of CA, and thus may be used for therapeutic delivery. Research support: World Class University program (R31–20029), Ministry of Education, Science and Technology, South Korea.