A novel inhibitory effect of Antrodia camphorata extract on vascular smooth muscle cell migration and neointima formation in mice

Antrodia camphorata (AC) is a well-known traditional Chinese medicine that has been shown to inhibit proliferation and migration of cancer cells. We examined whether AC could inhibit rat aortic smooth muscle cell (RASMC) proliferation and migration and evaluated its effect on neointima formation in mouse carotid artery after injury. In Transwell migration assay and wound scratch assay, RASMCs were treated with AC or saline, and the number of migrated cells was counted or the distance was determined. Both assays showed that AC significantly inhibited platelet-derived growth factor (PDGF)-induced SMC migration. In 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) and 5-bromo-2'deoxyuridine (BrdU) proliferation assays, RASMCs were pretreated with AC or saline and stimulated with PDGF. Both assays showed that AC inhibited PDGF-induced SMC proliferation. The left common carotid arteries of C57BL/6 mice were ligated near the carotid bifurcation. The mice were given water or AC for 4 weeks. The severity of neointima formation was expressed as the neointima/media (N/M) ratio. The AC-treated mice had less neointima formation at 4 weeks after carotid ligation (N/M ratio, water versus 250 versus 1250 mg/kg AC; 1.33 ± 0.87 versus 0.83 ± 0.45 versus 0.63 ± 0.32, P < 0.05). Our data indicate that AC is an effective inhibitor of PDGF-induced RASMC proliferation and migration. AC treatment reduced neointima formation in this mouse carotid ligation model.