Sinigrin attenuates the progression of atherosclerosis in ApoE^−/− mice fed a high-cholesterol diet potentially by inhibiting VCAM-1 expression

Atherosclerosis is a complex inflammatory disease associated with elevated levels of atherogenic molecules for leukocyte recruitment. Sinigrin (2-propenylglucosinolate) is found mainly in broccoli, brussels sprouts, and black mustard seeds. Recently, sinigrin has received attention for its role in disease prevention and health promotion. In this study, we examined the effect of sinigrin on development of atherosclerosis in ApoE^−/− mice and the expression of adhesion molecules in vascular smooth muscle cells (VSMCs). The serum concentrations of lactate dehydrogenase (LDH), triglyceride (TG), total cholesterol (TC), low density lipoprotein (LDL), calcium (Ca²⁺), and pro-inflammatory cytokines were reduced by sinigrin treatment in ApoE^−/− mice. In addition, oral administration of sinigrin attenuated the mRNA expression of vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), C-C motif chemokine ligand 2 (CCL2), and CCL5 on aorta tissues and 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGR), liver X receptor (LXR), sterol regulatory element-binding protein-2 (SREBP-2), and low density lipoprotein receptor (LDLR) on liver tissues in ApoE^−/− mice. To provide a potential mechanism underlying the action of sinigrin, we evaluated the in vitro effect of sinigrin on the expression of the VCAM-1 in TNF-α-induced VSMCs. The increased expression of VCAM-1 by TNF-α stimulation was significantly suppressed by the treatment of sinigrin (1–100 μg/ml) and sinigrin inhibited the nuclear translocation of NF-κB and the phosphorylation of p38 MAPK and JNK pathways, suggesting that sinigrin decreases the TNF-α-stimulated VCAM-1 expression through the suppression of NF-κB and MAP kinases signaling pathways. Overall, sinigrin has the potential to be used in reducing the risks of atherosclerosis.