Objective: To investigate the effects of Korean Magnolia obovata crude extract (KME) on plateletderived growth factor (PDGF)-BB-induced proliferation and migration of vascular smooth muscle cells (VSMCs).Methods: KME composition was analyzed by high-performance liquid chromatography (HPLC).VSMCs were isolated from the aorta of a Sprague-Dawley rat,incubated in serum free-Dulbecco's modified Eagle's medium in the presence or absence of KME (10,30,100,and 300 μ g/mL),then further treated with PDGF-BB (10 ng/mL).VSMC proliferation was detected using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and VSMC migration was determined using the Boyden chamber and scratch wound healing assays.Western blot analysis was used to detect phosphorylation of extracellular signal-regulated protein kinases 1 and 2 (p-ERK1/2),protein kinase B (p-Akt),and stress-activated protein kinase/c-Jun NH2-terminal kinase (p-SAPK/JNK).The antimigration and proliferation effects of KME were tested using aortic sprout outgrowth.Results: The HPLC analysis identified honokiol (0.45 mg/g) and magnolol (0.34 mg/g) as the major components of KME.KME (30,100,and 300 μ g/mL) significantly decreased the proliferation and migration of PDGF-BB-stimulated (10 ng/mL) VSMCs and the PDGF-BB-induced phosphorylation of EKR1/2,Akt,and SAPK/JNK (P＜0.05).Furthermore,PDGF-BB-induced VSMCs treated with 300 μ g/mL of KME showed reduction in aortic sprout outgrowth.Conclusion: KME could inhibit abnormal proliferation and migration of VSMCs by down-regulating the phosphorylation of EKR1/2 and Akt.Thus,KME might be a functional food for preventing vascular disorders.