MicroRNA-335-5p suppresses lower extremity deep venous thrombosis by targeted inhibition of PAI-1 via the TLR4 signalingpathway.

This study aims to investigate the effects of microRNA-335-5p (miR-335-5p) on lower-extremity deep vein thrombosis (LEDVT) by targeting PAI-1 through the TLR4 signaling pathway in rat models. siRNA, mimic, and inhibitor were used for transfection. The miR-335-5p expression was detected by in situ hybridization. CCK-8 assay and flow cytometry were adopted to detect proliferation, cell cycle, and apoptosis, respectively. Scratch test and Matrigel-based tube formation assay were used to detect the effect of miR-335-5p on cell migration ability and tube formation ability. A miR-335-5p lentivirus plasmid was constructed and injected into LEDVT rats. The length and weight of thrombus were measured, changes of thrombus recanalization were observed by CD34 immunohistochemistry, and levels of PAI-1 and inflammatory factors in femoral vein blood were detected by ELISA. LEDVT rats showed a higher AOD value of PAI-1, higher expression of PAI-1, NF-κB, Rac1, IL-1β, and TLR4 and a lower miR-335-5p expression. PAI-1 and miR-335-5p were negatively correlated. Compared to the blank and siRNA-NC groups, the miR-335-5p mimic and siRNA-PAI-1 groups showed declined expression of PAI-1, TLR4, NF-κB, Rac1, and IL-1β, increased proliferation and tube formation abilities, less cells in G0/G1 phase, and decreased apoptosis, decreased length and weight of thrombus, organized thrombus, increased new blood vessels, and decreased levels of PAI-1, IL-1, IL-6, and Tnf-a. miR-335-5p may suppress the occurrence and development of LEDVT in rats by repressing the activation of the TLR4 signaling pathway by targeted inhibition of PAI-1.