Grape seed proanthocyanidin extract inhibits platelet-derived growth factor induced proliferation of airway smooth muscle cells

Objective To explore the effect of grape seed proanthocyanidin extract(GSPE)on the proliferation of airway smooth muscle cells(ASMCs)induced by platelet-derived growth factor(PDGF)and the underlying molecular mechanism. Methods ASMCs of primary rat were cultured.MTT and flow cytometry were used to detect the cell proliferation activity and cell cycle distribution of ASMCs which were treated with PDGF and GSPE respectively.The expression levels of cyclin D1, extracellular regulated protein kinases(ERK)1/2, p-ERK1/2 and β-actin protein in each group ASMCs were analyzed using western blotting assay after ERK1/2 inhibitor PD98059 intervention. Results Compared with control group, cell proliferative activity, S phase fraction and the expression of cyclin D1 and p-ERK1/2 protein increased in PDGF induced group(P<0.05). These effects induced by PDGF could be reversed by GSPE.PD98059 also could block PDGF induced higher expression of p-ERK1/2 and cyclin D1 proteins in rat ASMCs. Conclusion GSPE can inhibit PDGF induced cell proliferation and via ERK1/2 signaling pathway in rat ASMCs, which provide a new way for treatment of bronchial asthma. Key words: Grape seed proanthocyanidin extract; Airway smooth muscle cells; Proliferation; Extracellular regulatory protein kinase