3.7 Sulforaphane
Sulforaphane is an isothiocyanate, which is produced by the conversion of glucoraphanin through the enzyme myrosinase (Vanduchova, Anzenbacher, & Anzenbacherova, 2019). Sulforaphane, a potent antioxidant, is primarily found in several Brassicaceae vegetables, such as broccoli, cauliflower, cabbage, and Brussels sprouts. Sulforaphane has often been shown to protect cells from oxidative stress in cardiomyocytes and neural cells (Guerrero-Beltran, Calderon-Oliver, Pedraza-Chaverri, & Chirino, 2012). The nuclear factor erythroid-2-related factor 2 (Nrf2), a basic leucine zipper transcription factor that serves as a defense mechanism against oxidative stress, has been shown to be activated by sulforaphane (Bai et al., 2015; Houghton, Fassett, & Coombes, 2016). SIRT1 is a potential target gene of miR-34a (M, M, & CJ, 2008) and the role of the miR-34a/SIRT1 axis in oxidative stress-induced cellular damage has been demonstrated (Y. Guo et al., 2017). Sulforaphane was found to protect endothelial cells from oxidative stress by regulating the miR-34a/SIRT1 axis through upregulation of Nrf2 (T. Li et al., 2021). In addition, a study found that sulforaphane can reduce lipopolysaccharide-induced cell damage and oxidative stress by inhibiting miR-155 in microglia (Eren et al., 2018). MiR-155 was proved to aggravate the carotid atherosclerotic lesion through induction of endothelial cell apoptosis and activation of inflammasome in macrophages (R. Yin et al., 2019). Therefore, it is possible that sulforaphane may limit the formation of atherosclerotic lesions by inhibiting miR-155, but clearly, more studies are needed to confirm this hypothesis.