Andrographolide, a Novel NF-κB Inhibitor, Induces Vascular Smooth Muscle Cell Apoptosis via a Ceramide-p47phox-ROS Signaling Cascade

Abstract EN

Atherosclerosis is linked with the development of many cardiovascular complications.

Abnormal proliferation of vascular smooth muscle cells (VSMCs) plays a crucial role in the development of atherosclerosis.

Accordingly, the apoptosis of VSMCs, which occurs in the progression of vascular proliferation, may provide a beneficial strategy for managing cardiovascular diseases.

Andrographolide, a novel nuclear factor-κB inhibitor, is the most active and critical constituent isolated from the leaves of Andrographis paniculata.

Recent studies have indicated that andrographolide is a potential therapeutic agent for treating cancer through the induction of apoptosis.

In this study, the apoptosis-inducing activity and mechanisms in andrographolide-treated rat VSMCs were characterized.

Andrographolide significantly induced reactive oxygen species (ROS) formation, p53 activation, Bax, and active caspase-3 expression, and these phenomena were suppressed by pretreating the cells with N-acetyl-L-cysteine, a ROS scavenger, or diphenylene iodonium, a nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (Nox) inhibitor.

Furthermore, p47phox, a Nox subunit protein, was phosphorylated in andrographolide-treated rat VSMCs.

However, pretreatment with 3-O-methyl-sphingomyelin, a neutral sphingomyelinase inhibitor, significantly inhibited andrographolide-induced p47phox phosphorylation as well as Bax and active caspase-3 expression.

Our results collectively demonstrate that andrographolide-reduced cell viability can be attributed to apoptosis in VSMCs, and this apoptosis-inducing activity was associated with the ceramide-p47phox-ROS signaling cascade.