Abstract:

Objective To observe the effects of transcription factor FoxO3a phosphorylation on the proliferation of vascular smooth muscle cells after common carotid artery balloon injury. Methods Thirty male SD rats were randomly divided into control group (group C, n＝6) and balloon injury group (group S, n＝24), and the latter was subdivided into group S1 (6 h after surgery, n＝6), group S2 (12 h after surgery, n＝6), group S3 (24 h after surgery, n＝6) and group S4 (72 h after surgery, n＝6). Left common carotid artery balloon injury was performed in rats of group S, the injured arteries were harvested to culture the vascular smooth muscle cells, the expression of FoxO3a mRNA was detected by RT-PCR, the expression of FoxO3a protein was detected by western blotting, and the cell proliferation was determined by MTT. Results Compared with group C, group S2, group S3 and group S4, the expression of phosphorylated FoxO3a protein in vascular smooth muscle cells in group S1 increased significantly after vascular injury (P<0.01). Compared with group C, the cell proliferation in group S1 increased significantly 2 d, 3 d, 4 d and 5 d after culture (P<0.01). Conclusion FoxO3a is quickly phosphorylated after vascular injury. The duration of phosphorylation may last for a short while, and may be associated with the significant increase of proliferation of vascular smooth muscle cells. It is suggested that the phosphorylation of FoxO3a may play an important role in the repair of vascular injury.

Key words: FoxO3a, phosphorylate, vascular smooth muscle cell, proliferation