Tanshinone IIA suppresses the progression of atherosclerosis by inhibiting the apoptosis of vascular smooth muscle cells and the proliferation and migration of macrophages induced by ox-LDL

The profound inhibitory effect of Tanshinone IIA (Tan IIA) on atherosclerosis has been demonstrated, whereas the latent mechanism is not completely cleared. This study aimed to investigate the cellular and molecular mechanisms underlying Tan IIA protecting against atherosclerosis. Oil Red O staining and ELISA assay showed that Tan IIA suppressed the progress of atherosclerosis and reduced the levels of inflammatory cytokines in serum of apolipoprotein E deficient (ApoE -/- ) mice. Flow cytometry assay revealed that Tan IIA inhibited oxidized LDL (ox-LDL)-induced apoptosis of VSMCs. MTT and transwell assay indicated that Tan IIA suppressed the ox-LDL-stimulated proliferation and migration of RAW264.7 cells. Moreover, Tan IIA ameliorated inflammatory cytokine upregulation elicited by ox-LDL in RAW264.7 cells. Additionally, Tan IIA inhibited the apoptosis of VSMCs and decreased the levels of MMP-2, MMP-9 in ApoE-/- mice. In conclusion, our study demonstrated Tan IIA suppressed the progression of atherosclerosis by inhibiting vascular inflammation, apoptosis of VSMCs and proliferation and migration of macrophages induced by ox-LDL.