Imperatorin Derivative OW1, a New Vasoactive Compound, Attenuates Cell Proliferation and Migration by Inhibiting Nox1-mediated Oxidative Stress.

OBJECTIVES:Reactive oxygen species (ROS) are involved in the structural remodelling of vascular segments and vascular beds. We identified a new imperatorin derivative, OW1, which has significant effects on vasodilation and inhibits vascular remodelling in hypertensive rats. In this study, we investigated whether OW1 inhibits vascular cell proliferation and migration by attenuating Nox1-ROS signalling.METHODS:Vascular smooth muscle cells (VSMCs) were treated with OW1 (1, 3 and 10 µmol/L) for 24 h incubation, and it has been analysed for proliferation and peroxidation levels. Moreover, the mRNA and protein levels of nicotinamide adenine dinucleotide phosphate oxidase (Noxs) were measured by RT-PCR and western blot. Furthermore, Nox1-ROS-MAPK/MMP mediated cell proliferation was detected by western blot.KEY FINDINGS:Ang II-induced increases in the levels of peroxidation and Noxs in VSMCs were also inhibited by OW1. OW1 attenuates cell proliferation and migration through the MAPK pathway and MMPs. OW1 treatment had no significant effects on cell migration, ROS levels, or the expression of phosphorylated MAPKs in VSMCs when Nox1 was knocked down. OW1 reduced ROS levels and expression of phosphorylated MAPKs in NIH3T3 cells with a Nox1 overexpression plasmid.CONCLUSION:OW1 may inhibit vascular remodelling by downregulating the Nox1-ROS-MAPK/MMP signalling pathway.