Blockade of oxidative stress and Ras-MEK1/2-ERK1/2 pathway is involved in fasudil attenuating balloon injury-induced neointima hyperplasia / 中华老年医学杂志

ABSTRACT

Objective To evaluate the effects of fasudil on neointima hyperplasia in rat carotid artery balloon-injury model,and explore the potential molecular mechanisms of this effect.Methods Totally 30 male Sprague-Dawley (SD) rats were randomly divided into sham operation group,balloon injury group,2.5 ml/kg fasudil intervention group,5 ml/kg fasudil intervention group,10 ml/kg fasudil intervention group.The intima-to media(I/M) area ratio of neointima was calculated at 14th day after operation; the protein expression of proliferating cell nuclear antigen(PCNA) was measured by immunohistochemical and the integrated optical density (IA) was calculated.As the marker of oxidative stress,the levels of 8-hydroxy-2'-dcoxyguanosine (8OHdG) and malondialdehyde (MDA) were measured by enzyme-linked immunosorbent assay (ELISA).The expressions of phosphorylated and non phosphorylated Ras,mitogen activated protein kinase kinase (MEK1/2) and extracellular signal regulated kinase (ERK1/2) were measured by Western blot.Results The I/M ratios were (0.22 ± 0.01) in sham operation group,(2.71 ± 0.23) in balloon injury group,( 1.72 ±0.24)in 2.5 ml/kg fasudil intervention group,(1.23±0.11)in 5 ml/kg fasudil intervention group,(0.85±0.12)in 10 ml/kg fasudil intervention group.As compared with sham operation group,I/M area ratio was increased in balloon injury group,and three fasudil intervention group inhibited neointima hyperplasia in a dose-dependent manner (all P＜0.01).The IA indexes were(15.11 ±1.42),(53.42±2.30),(45.25±1.62),(22.55±0.88) and(19.61±0.79) in the above five groups,respectively,showing the fasudil inhibited PCNA expression (all P＜0.01).Fasudil also inhibited the levels of 8-OHdG and MDA in a dose-dependent manner [8OHdG(54.34±4.50)μg/kg,(106.81 ± 6.67)μg/kg,(94.21 ± 3.34) μg/kg,(65.58 ± 5.13) μg/kg,(51.32 ± 2.34) μg/kg; MDA(19.94 ± 0.65 ) μmol/kg,( 58.83 ± 2.81 ) μmol/kg,(48.94 ± 1.35 ) μmol/kg,(40.62 ± 3.24 )μmol/kg,( 36.85 ± 0.91)μmol/kg (all P＜0.01)].Compared with balloon injury group,the relative expressions of Ras in three fasudil intervention group were 0.49±0.12,0.39±0.13,0.20±0.23 vs.0.62±0.10(P＜0.05 or,P＜0.01); MEK1/2 0.35±0.14,0.29±0.09,0.11±0.12 vs.0.56±0.1(P＜0.05 or,P＜0.01); ERK1/2 0.48±0.15,0.32±0.08,0.12±0.09 vs.0.64±0.13(P＜0.05 or,P＜0.01).The activations of ERK1/2,MEK1/2 and Ras were strongly suppressed in fasudil treated samples on day 14 after balloon injury.Conclusions Blockade of oxidative stress and Ras MEK1/2 ERK1/2 pathway is involved in the fasudil attenuating of balloon injury-induced neointima hyperplasia