MiR-20b-5p involves in vascular aging induced by hyperhomocysteinemia.

Hyperhomocysteinemia (HHcy) is an independent risk factor of atherosclerosis (AS). Some reports have shown that homocysteine (Hcy) could accelerate the development of AS by promoting endothelial cell senescence. miRNAs were widely involved in the pathophysiology of HHcy. However, few studies have focused on the changes of miRNA-mRNA networks in the artery of HHcy patients. For this reason, RNA-sequencing was adopted to investigate the expression of miRNA and mRNA in HHcy model mouse arteries. We found that the expression of 216 mRNAs and 48 miRNAs were significantly changed. Using TargetScan and miRDB web tools, 29 miRNA-mRNA pairs were predicted. Notably, miR-20b-5p and FJX1 shared the highest predicted score in TargetScan, and further study indicated that the miR-20b-5p inhibitor significantly upregulated the FJX1 expression in HHcy human umbilical vein endothelial cells (HUVECs) model. PPI analysis revealed an important sub-network which was centered on CDK1. Gene ontology (GO) enrichment analysis showed that HHcy had a significant effect on cell cycle. Further experiments found that Hcy management increased reactive oxygen species (ROS) generation, the activity of senescence associated β-galactosidase (SA-β-gal) and the protein expression of p16 and p21 in HUVECs, which were rescued by miR-20b-5p inhibitor. In general, our research indicated the important role of miR-20b-5p in HHcy-related endothelial cell senescence.