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Objective: Abnormal proliferation and migration of vascular smooth muscle cells ( VSMCs) are essential for vascular remodeling. Natural compounds with diterpene chinone or phenolic acid structure from Salvia miltiorrhiza, an eminent medicinal herb widely used to treat cardiovascular diseases in China, can effectively attenuate vascular remodeling induced by vascular injury. However, it remains unknown whether Salvia miltiorrhiza -derived miRNAs can protect VSMCs from injury by environmental stimuli. Here, we explored the role and underlying mechanisms of Salvia miltiorrhiza -derived Sal-miR-1 and 3 in the regulation of VSMC migration and monocyte adhesion to VSMCs induced by thrombin. Methods: A mouse model for intimal hyperplasia was established by the ligation of carotid artery and the injured carotid arteries were in situ-transfected with Sal-miR-1 and 3 using F-127 pluronic gel. The vascular protective effects of Sal-miR-1 and 3 were assessed via analysis of intimal hyperplasia with pathological morphology. VSMC migration and adhesion were analyzed by the wound healing, transwell membrane assays, and time-lapse imaging experiment. Using loss- and gain-of-function approaches, Sal-miR-1 and 3 regulation of OTUD7B/KLF4/NMHC IIA axis was investigated by using luciferase assay, co-immunoprecipitation, chromatin immunoprecipitation, western blotting, etc. Results: Salvia miltiorrhiza- derived Sal-miR-1 and 3 can enter the mouse body after intragastric administration, and significantly suppress intimal hyperplasia induced by carotid artery ligation. In cultured VSMCs, these two miRNAs inhibit thrombin-induced the migration of VSMCs and monocyte adhesion to VSMCs. Mechanistically, Sal-miR-1 and 3 abrogate OTUD7B upregulation by thrombin via binding to the different sites of the OTUD7B 3'UTR. Most importantly, OTUD7B downregulation by Sal-miR-1 and 3 attenuates KLF4 protein levels via decreasing its deubiquitylation, whereas decreased KLF4 relieves its repression of transcription of NMHC IIA gene and thus increases NMHC IIA expression levels. Further, increased NMHC IIA represses VSMC migration and monocyte adhesion to VSMCs via maintaining the contractile phenotype of VSMCs. Conclusions: Our studies not only found the novel bioactive components from Salvia miltiorrhiza but also clarified the molecular mechanism underlying Sal-miR-1 and 3 inhibition of VSMC migration and monocyte adhesion to VSMCs. These results add important knowledge to the pharmacological actions and bioactive components of Salvia miltiorrhiza . Sal-miR-1 and 3-regulated OTUD7B/KLF4/NMHC IIA axis may represent a therapeutic target for vascular remodeling.

Increased activity of the PI3K/AKT/mTOR pathway has been observed in chronic myeloid leukemia (CML). Morin, a kind of flavonoid, exhibits a significant anticancer activity by suppressing the PI3K/AKT signaling pathway. However, the effect of morin on CML and its underlying mechanisms is poorly understood. Here, we found that morin dose dependently inhibited the proliferation of CML cell lines K562 and KCL22 and induced their apoptosis, with a significant increase in cell apoptosis upon exposure of cells to 50 mmol/L morin. Moreover, morin significantly reduced CML xenograft growth in nude mice. Mechanically, morin attenuated phosphorylated AKT level by upregulating PTEN expression, thus leading to the inhibition of AKT signaling. Knockdown of PTEN by its siRNA completely abrogated morin-induced cell apoptosis, indicating that PTEN mediates the inductive effect of morin on CML cell apoptosis. More importantly, we found that miR-188-5p was significantly upregulated in CML patients and CML cell lines. Treating CML cells with morin markedly downregulated the miR-188-5p expression level. Further, we demonstrated that miR-188-5p repressed PTEN expression by directly targeting its 3 0 -UTR. miR-188-5p downregulation induced by morin enhanced CML cell apoptosis by relieving miR-188-5p repression of PTEN expression. In summary, morin exerts significant anticancer efficacy in CML by regulating the miR-188-5p/PTEN axis and thus repressing the PI3K/AKT signaling.