Ligustrazine alleviates the progression of coronary artery calcification by inhibiting caspase-3/GSDME mediated pyroptosis.

Coronary artery calcification (CAC) is an early marker for atherosclerosis and is mainly induced by the osteoblast-like phenotype conversion of vascular smooth muscle cells (VSMCs). Recent reports indicate that NOD-like receptor protein 3 (NLRP3)-mediated pyroptosis plays a significant role in the calcification of vascular smooth muscle cells (VSMCs), making it a promising target for treating calcific aortic valve disease (CAC). Ligustrazine, or tetramethylpyrazine (TMP), has been found effective in various cardiovascular and cerebrovascular diseases and is suggested to inhibit NLRP3-mediated pyroptosis. However, the function of TMP in CAC is unknown. Herein, influences of TMP on β-glycerophosphate (β-GP)-stimulated VSMCs and OPG^-/- mice were explored. Mouse Aortic Vascular Smooth Muscle (MOVAS-1) cells were stimulated by β-GP with si- caspase-3, si- Gasdermin E (GSDME) or TMP. Increased calcification, reactive oxygen species (ROS) level, Interleukin-1beta (IL-1β) and Interleukin-18 (IL-18) levels, lactate dehydrogenase (LDH) release, enhanced apoptosis, and activated cysteine-aspartic acid protease-3 (caspase-3)/GSDME signaling were observed in β-GP-stimulated MOVAS-1 cells, which was sharply alleviated by si-caspase-3, si-GSDME or TMP. Furthermore, the impact of TMP on the β-GP-induced calcification and injury in MOVAS-1 cells was abolished by raptinal, an activator of caspase-3. Subsequently, OPG^-/- mice were dosed with TMP or TMP combined with raptinal. Calcium deposition, increased nodules, elevated IL-1β and IL-18 levels, upregulated CASP3 and actin alpha 2, smooth muscle (ACTA2), and activated caspase-3/GSDME signaling in OPG^-/- mice were markedly alleviated by TMP, which were notably reversed by the co-administration of raptinal. Collectively, TMP mitigated CAC by inhibiting caspase-3/GSDME mediated pyroptosis.