Molecular mechanism of p38 signaling pathway regulation for proliferation and apoptosis of rat vascular smooth muscle cells

AIM:To investigate the relationship between p38 signal transduction pathway and the proliferation and apoptosis of vascular smooth muscle cells (VSMCs) in rats of old age and to establish a mechanism of p38-targeted treatment for VSMCs. METHODS: Rat VSMCs were treated with SB203580 (a selective p38 inhibitor). MTT assay and flow cytometry were used to measure proliferation and apoptosis. Expressions of p-p38, MKK3, GADD153 and C-myc proteins were measured by Western blot. RESULTS: SB203580 inhibited cell proliferation, induced apoptosis in a dose- and time-dependent manner and resulted in a significant downregulation of p-p38, GADD153 and C-myc (P<0.01). CONCLUSION: Our results show that blocked p38 signaling pathway induces apoptosis and inhibits proliferation of VSMC through decreasing the GADD153 and C-myc expression of p38 downstream target genes.