[Mechanism of salidroside in inhibiting proliferation, migration and promoting phenotypic switching of arterial smooth muscle cells].

This study aims to examine the effect of salidroside(SAL) on the phenotypic switching of human aortic smooth muscle cells(HASMC) induced by the platelet-derived growth factor-BB(PDGF-BB) and investigate the pharmacological mechanism. Firstly, the safe concentration of SAL was screened by the lactate dehydrogenase release assay. HASMC were divided into control, model, and SAL groups, and the cells in other groups except the control group were treated with PDGF-BB for the modeling of phenotypic switching. Cell proliferation and migration were detected by the cell-counting kit(CCK-8) assay and Transwell assay, respectively. The cytoskeletal structure was observed by F-actin staining with fluorescently labeled phalloidine. The protein levels of proliferating cell nuclear antigen(PCNA), migration-related protein matrix metalloprotein 9(MMP-9), fibronectin, α-smooth muscle actin(α-SMA), and osteopontin(OPN) were determined by Western blot. To further investigate the pharmacological mechanism of SAL, this study determined the expression of protein kinase B(Akt) and mammalian target of rapamycin(mTOR), as well as the upstream proteins phosphatase and tensin homologue(PTEN) and platelet-derived growth factor receptor ß(PDGFR-ß) and the downstream protein hypoxia-inducible factor-1α(HIF-1α) of the Akt/mTOR signaling pathway. The results showed that the HASMCs in the model group presented significantly increased proliferation and migration, the switching from a contractile phenotype to a secretory phenotype, and cytoskeletal disarrangement. Compared with the model group, SAL weakened the proliferation and migration of HASMC, promoted the expression of α-SMA(a contractile phenotype marker), inhibited the expression of OPN(a secretory phenotype marker), and repaired the cytoskeletal disarrangement. Furthermore, compared with the control group, the modeling up-regulated the levels of phosphorylated Akt and mTOR and the relative expression of PTEN, HIF-1α, and PDGFR-ß. Compared with the model group, SAL down-regulated the protein levels of phosphorylated Akt and mTOR, PTEN, PDGFR-ß, and HIF-1α. In conclusion, SAL exerts a protective effect on the HASMCs exposed to PDGF-BB by regulating the PDGFR-ß/Akt/mTOR/HIF-1α signaling pathway.

Long non-coding RNAs: Modulators of phenotypic transformation in vascular smooth muscle cells.

Long non-coding RNA (lncRNAs) are longer than 200 nucleotides and cannot encode proteins but can regulate the expression of genes through epigenetic, transcriptional, and post-transcriptional modifications. The pathophysiology of smooth muscle cells can lead to many vascular diseases, and studies have shown that lncRNAs can regulate the phenotypic conversion of smooth muscle cells so that smooth muscle cells proliferate, migrate, and undergo apoptosis, thereby affecting the development and prognosis of vascular diseases. This review discusses the molecular mechanisms of lncRNA as a signal, bait, stent, guide, and other functions to regulate the phenotypic conversion of vascular smooth muscle cells, and summarizes the role of lncRNAs in regulating vascular smooth muscle cells in atherosclerosis, hypertension, aortic dissection, vascular restenosis, and aneurysms, providing new ideas for the diagnosis and treatment of vascular diseases.