Abnormal communication between endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) promotes vascular diseases, including atherogenesis. ETS variant transcription factor 2 (ETV2) plays a substantial role in pathological angiogenesis and the reprogramming of ECs; however, the role of ETV2 in the communication between ECs and VSMCs has not been revealed. To investigate the interactive role of ETV2 in the EC to VSMC phenotype, we first showed that treatment with a conditioned medium from ETV2-overexpressed ECs (Ad-ETV2 CM) significantly increased VSMC migration. The cytokine array showed altered levels of several cytokines in Ad-ETV2 CM compared with those in normal CM. We found that C-X-C motif chemokine 5 (CXCL5) promoted VSMC migration using the Boyden chamber and wound healing assays. In addition, an inhibitor of C-X-C motif chemokine receptor 2 (CXCR2) (the receptor for CXCL5) significantly inhibited this process. Gelatin zymography showed that the activities of matrix metalloproteinase (MMP)-2 and MMP-9 increased in the media of VSMCs treated with Ad-ETV2 CM. Western blotting revealed a positive correlation between Akt/p38/c-Jun phosphorylation and CXCL5 concentration. The inhibition of Akt and p38-c-Jun effectively blocked CXCL5-induced VSMC migration. In conclusion, CXCL5 from ECs induced by ETV2 promotes VSMC migration via MMP upregulation and the activation of Akt and p38/c-Jun.

Yohimbine (YHB) has been reported to possess anti-inflammatory, anticancer, and cardiac function-enhancing properties. Additionally, it has been reported to inhibit the proliferation, migration, and neointimal formation of vascular smooth muscle cells (VSMCs) induced by platelet-derived growth factor (PDGF) stimulation by suppressing the phospholipase C-gamma 1 pathway. However, the transcriptional regulatory mechanism of YHB controlling the behavior of VSMCs is not fully understood. In this study, YHB downregulated the expression of cell cycle regulatory proteins, such as proliferating cell nuclear antigen (PCNA), cyclin D1, cyclin-dependent kinase 4 (CDK4), and cyclin E, by modulating the transcription factor FOXO3a in VSMCs induced by PDGF. Furthermore, YHB decreased p-38 and mTOR phosphorylation in a dose-dependent manner. Notably, YHB significantly reduced the phosphorylation at Y397 and Y925 sites of focal adhesion kinase (FAK), and this effect was greater at the Y925 site than Y397. In addition, the expression of paxillin, a FAK-associated protein known to bind to the Y925 site of FAK, was significantly reduced by YHB treatment in a dose-dependent manner. A pronounced reduction in the migration and proliferation of VSMCs was observed following co-treatment of YHB with mTOR or p38 inhibitors. In conclusion, this study shows that YHB inhibits the PDGF-induced proliferation and migration of VSMCs by regulating the transcription factor FOXO3a and the mTOR/p38/FAK signaling pathway. Therefore, YHB may be a potential therapeutic candidate for preventing and treating cardiovascular diseases such as atherosclerosis and vascular restenosis.

The abnormal proliferation and migration of vascular smooth muscle cells (VSMCs) are a primary cause of cardiovascular diseases such as atherosclerosis and restenosis after angioplasty. Pinocembrin (5,7-dihydroxyflavanone, PCB), a natural flavonoid compound found abundantly in propolis, has been reported to have antibacterial, anti-inflammatory, antioxidant, and anticancer effects, and cardiac function improvement in ischemic heart disease. In this study, the protective effects of PCB against the migration and proliferation of VSMCs were investigated. MTT and BrdU assays were performed to estimate the cytotoxicity and cell proliferative activity of PCB, respectively. Rat aortic VSMC migrations and neointima formation were evaluated using wound healing, boyden chamber assays, and in balloon-injured (BI) rat, respectively. PCB suppressed the phosphorylated levels of p38 in PDGF-BB-induced VSMCs followed by reducing the expression of MMP2 and 9. PCB downregulated the expression levels of cell cycle regulatory proteins such as PCNA, CDK2, CDK4, and Cyclin D1. Furthermore, the phosphorylated levels of FAK at Y397 and Y925 sites and the expression levels of FAK-related proteins such as Integrin β1, Paxillin, Talin, and Vinculin were significantly reduced by PCB in PDGF-BB-induced VSMCs. The neointima formation was markedly decreased by PCB administration in the carotid artery of a balloon-injured rat. In conclusion, PCB inhibits the proliferation and migration of VSMCs by stimulation of PDGF-BB through the regulation of the p38 and FAK signaling pathway. Therefore, PCB may be a promising therapeutic candidate for preventing and treating cardiovascular diseases such as atherosclerosis and restenosis.