西洛他唑对糖尿病大鼠主动脉VCAM-1、NF-κB及PPARs的影响

目的观察西洛他唑对糖尿病大鼠主动脉血管细胞粘附分子-1(VCAM-1)、核因子(NF)-κB及过氧化物酶增殖体激活受体(PPAR s)的影响,探讨西洛他唑影响VCAM-1表达的上游信号通路。方法腹腔注射链脲佐菌素(65 mg.kg-1)制备糖尿病模型,正常对照组大鼠腹腔注射柠檬酸钠缓冲液(NC,n=8)。随机将成模的32只糖尿病大鼠分为糖尿病模型组(DM,n=12)、高剂量西洛他唑组(GX,27mg.kg-1.d-1,n=10)与低剂量西洛他唑组(DX,9 mg.kg-1.d-1,n=10)。治疗8 wk,采用免疫组织化学法检测各组主动脉组织VCAM-1表达及P65亚基核转位情况;原位杂交和凝胶电泳迁移率改变分析法(EMSA)检测主动脉VCAM-1 mRNA表达及NF-κB-DNA结合活性;RT-PCR或Real-Time PCR检测PPARα、PPARγmRNA表达。结果①与正常组相比,糖尿病大鼠主动脉内皮VCAM-1及其基因表达升高(P<0.01),NF-κB P65核转位及活化增强(P<0.01),PPARγmRNA表达为正常大鼠的1.7倍,而PPARαmRNA表达下降(P<0.01)。②与糖尿病组相比,高剂量西洛他唑治疗组主动脉内皮VCAM-1及其基因表达降低(P<0.01),NF-κB P65核转位及活化被抑制(P<0.01),PPARγmRNA表达比糖尿病大鼠下降73%,而PPARαmRNA则上升(P<0.05)。结论高剂量西洛他唑抑制糖尿病大鼠主动脉内皮表达VCAM-1,这可能与其对PPARs表达、NF-κB核转位及其DNA结合活性的影响有关。

Effects of ciloistazol VCAM-1NF-KB and PPARs in aorta of STZ-induced diabetes

Aim To investigate the in vivo effects of cilostazol,a novel phosphodiesterase III inhibitor,on signaling regulation,that is PPARs and NF-κB on vascular cell adhesion molecule-1(VCAM-1) in aorta of diabetic rats.Methods Diabetes was induced by intraperitoneally injecting fasted SD rats with streptozocin(STZ) at the dose of 65 mg· kg~(-1).32 diabetic rats were randomly divided into three groups,diabetes mellitus group(DM,n=12),high dosage of cilostazol group(GX,27 mg·kg~(-1)·d~(-1),n=10) and low dosage of cilostazol(DX,9 mg·kg~(-1)·d~(-1),n=10),plus normal control group(NC,n=8).After treatment for 8 weeks,using immunohistochemitry(IHC),in situ hybridyzation(ISH) and electrophoresis mobility shift assay(EMSA),we determined expression of VCAM-1,translocation of P65 subunit and activity of NF-κB in aorta tissues.PPARα and PPARγ were examined by RT-PCR or Real-Time PCR.Results ①Compared with NC group,diabetic groups had elevated VCAM-1 expression of protein and mRNA(P<0.01),and increased activation and translocation of NF-κB(P<0.01) on rat aortic artery endothelial surface.PPARr mRNA was increased 1.7 times and PPARα mRNA was decreased(P<0.01) in DM group.② High dose of cilostazol suppressed VCAM-1 expression of protein and mRNA,activation and translocation of NF-κB(P<0.01).Reduction of PPARγ mRNA in GX group was 73% compared with that of DM group,but PPARα was up-regulated(P<0.05).Conclusion As PPARs may have some effects on NF-κB,our findings first provide potential new insight into the possible mechanism of cilostazol on NF-κB-by PPARs.This provides an experimental evidence for further evaluation of the diabetic macroangiopathy protective effect of cilostazol.