Peripheral Blood Levels of miR-448 and SIRT1 in Patients with Deep Venous Thrombosis and Their Relationship

The goal of this study was to investigate the changes in peripheral blood levels of miR-448 and silent information regulator 1 (SIRT1) in patients with deep venous thrombosis (DVT) and to analyze their relationship.A total of 112 patients treated from January 2019 to June 2020 were divided into DVT group (n = 40) and non-DVT group (n = 72). Fasting venous blood was extracted to separate serum and peripheral blood mononuclear cells (PBMCs). Enzyme-linked immunosorbent assay (ELISA) was employed to measure serum SIRT1 protein, and qPCR was utilized to detect miR-448 expression in PBMCs. The clinical data, serum indicators, and expressions of SIRT1 and miR-448 were compared, and the correlations of miR-448 and SIRT1 with DVT were analyzed using a multivariate Cox regression model. TargetScan Release 7.1 was used to predict the possibility of binding sites between miR-448 and SIRT1 mRNA 3'-untranslated region (3'-UTR), and dual-luciferase reporter assay was used to determine the targeting of miR-448 and SIRT1. HeLa cells were divided into overexpression, inhibition, and blank control groups. The cells were harvested 24 hours after transfection, followed by detection of SIRT1 mRNA expression by qPCR and measurement of supernatant SIRT1 protein expression by ELISA.Serum SIRT1 protein level was lower and miR-448 expression in PBMCs was higher in DVT group than those in non-DVT group (p < 0.05). DVT group had a larger number of patients with vascular diseases and history of venous thrombosis than that of non-DVT group (p < 0.05). miR-448 was an independent risk factor for postoperative DVT, and SIRT1 was a protective factor (p < 0.01). There were potential complementary base binding sites between miR-448 and SIRT1 mRNA 3'-UTR. Dual-luciferase reporter assay verified the targeted regulation between miR-448 and SIRT1. HeLa cell SIRT1 mRNA expression and supernatant SIRT1 protein expression were lower in overexpression group while higher in inhibition group than those in blank control group (p < 0.05).Serum SIRT1 protein level decreases while miR-448 expression in PBMCs increases in patients with DVT, and miR-448 inhibits SIRT1 expression through binding to SIRT1 mRNA 3'-UTR with complementary bases, thus inducing inflammatory response to participate in the formation of DVT. Targeting miR-448 to regulate cytokine expression may become an effective target and approach for the treatment of DVT. miR-488 combined with SIRT1 has a high predictive value for the occurrence of DVT.