Morin inhibits PDGF-induced proliferation, migration, and invasion of vascular smooth muscle cells via modulating p27KIP1, AKT, and MMP-9 activities

• Published in: General physiology and biophysics 2018-09, Vol.37 (6), p.633-645
• Main Authors: Shin, Seung-Shick, Ko, Myeong-Cheol, Noh, Dae-Hwa, Hwang, Byungdoo, Park, Yujin, Park, Sung Lyea, Kim, Wun-Jae, Moon, Sung-Kwon
• Format: Article
• Language: English
• ISSN: 0231-5882
• DOI: 10.4149/gpb_2018028

Hyper-proliferation and migration of vascular smooth muscle cells (VSMCs) are closely associated with atherosclerosis. Recently, the flavonol morin has been reported to exhibit potent anti-oxidant and anti-inflammatory activities. Therefore, we investigated molecular mechanisms of morin in VSMCs stimulated by PDGF. Morin effectively inhibited PDGF-stimulated proliferation of VSMCs through a G1 cell-cycle arrest, leading to down-regulation of CDK2, CDK4, cyclin D1, and cyclin E proteins. Interestingly, PDGF markedly down-regulated p27KIP1 protein expression; however, morin treatment restored the p27KIP1expression to the basal level. Morin did not affect phosphorylation of MAPKs (ERK, p38, and JNK); however, phosphorylation of AKT was dramatically suppressed by morin in PDGF-stimulated VSMCs. Using the PI3K inhibitor, LY294002, we revealed that AKT is a key regulator in the inhibitory mechanism of morin against PDGF-induced proliferation of VSMCs. Morin disturbed migratory and invasive potential of VSMCs via suppression of matrix metalloproteinase-9 (MMP-9) activity. Using electrophoretic mobility shift assays, we verified that NF-κB, AP-1, and Sp-1 transcription factors are implicated in the mode of action of morin, which suppresses the MMP-9 activity in PDGF-induced VSMCs. Based on the results, we believe that morin may be a potential therapeutic agent for atherosclerosis without negative side effect.