ABSTRACT
AIM:To investigate the effect of 27nt-microRNA (27nt-miRNA) on the expression of smooth muscle 22α protein (SM22α) and the cell viability, migration and phenotypic changes of vascular smooth muscle cells (VSMCs).METHODS:The highly expression plasmids of 27nt-miRNA, and anti-27nt-miRNA and negative control plasmids were constructed, packaged with lentivirus and transfected into the rat primary VSMCs.Platelet-derived growth factor BB (PDGF-BB) was added to induce VSMCs phenotype conversion.The cell viability was measured by MTT assay.The migration ability was detected by scratch assay.The mRNA and protein expression of SM22αwas determined by RT-PCR, immunocytochemical staining and Western blot.RESULTS:Compared with normal group, the cell viability in PDGF-BB group was increased (P<0.05) , the migration ability was increased (P<0.05) and the expression of SM22αat mRNA and protein level was decreased (P<0.05).Compared with negative control lentiviral group, the cell viability in 27ntmiRNA over-expression group was decreased (P<0.05) , the migration ability was decreased (P<0.05) , and the mRNA and protein expression of SM22αwas increased (P<0.05).While in anti-27nt-miRNA group, the cell viability was increased (P<0.05) , the migration ability was increased (P<0.05) , and the mRNA and protein expression of SM22αwas decreased (P<0.05).CONCLUSION:27nt-miRNA significantly increases the expression of SM22α, while inhibits the viability and migration ability of VSMCs, and inhibits its phenotypic shift from contractile to synthetic.