化合物EXP-2528对Ang Ⅱ诱导大鼠脑微血管内皮细胞表达E-selectin和VCAM-1的影响(英文)

Effect of compound EXP-2528 on angiotensin Ⅱ-induced E-selectin and VCAM-1 expression in rat brain microvascular endothelial cells in vitro

本研究利用体外培养大鼠脑微血管内皮细胞(brain microvascular endothelial cells,BMEC)模型,探讨了血管紧张素(Ang)Ⅱ对大鼠脑微血管内皮细胞表达E-selectin和VCAM-1的影响及其机制,并评价了新型AT1受体拮抗剂化合物EXP-2528对其的影响。采用RT-PCR和Western blotting分别检测大鼠脑微血管内皮细胞E-选择素(E-selectin)和血管细粘黏附分子-1(vascular cell adhesion molecule-1,VCAM-1)的mRNA及蛋白的表达。结果显示1×10-7mol.L-1Ang Ⅱ分别孵育4 h和18 h可显著促进BMEC E-selectin及VCAM-1的mRNA及蛋白的表达,应用氯沙坦和新型选择性AT1受体拮抗剂化合物EXP-2528选择性阻断AT1受体对此有明显抑制作用。同时阻断AT1受体和AT2受体也可明显抑制Ang Ⅱ诱导的E-selectin及VCAM-1表达的增加,但是与单独阻断AT1受体相比无明显差异。而选择性阻断AT2受体对Ang Ⅱ诱导的E-selectin及VCAM-1的表达无明显影响。以上实验结果提示,AngⅡ可通过激动AT1受体上调BMEC E-selectin和VCAM-1的表达,参与脑血管疾病的发生发展。

The aim of this study is to investigate the effect and mechanism of angiotensin （Ang） II on E-selectin and vascular cell adhesion molecule-1 （VCAM-1） expression in rat brain microvascular endothelial cells （BMEC） and evaluate the effect of compound EXP-2528, a novel Ang Ⅱ type 1 （AT1） receptor antagonist. The experiment was performed in cultured BMEC of rat. The mRNA and protein expression of E-selectin and VCAM-1 in BMEC was analyzed by RT-PCR and Western blotting, respectively. The results showed that the mRNA and protein expression of E-selectin and VCAM-1 in BMEC were significantly upregulated by 4 h or 18 h exposure to 1×10-7 mol·L-1 Ang Ⅱ. These effects were abolished by pretreatment with the selective AT1 receptor antagonists losartan and compound EXP-2528, but not with the AT2 selective antagonist PD123319. Combining losartan with PD123319 also significantly inhibited Ang Ⅱ-induced E-selectin and VCAM-1 expression in BMEC, but there was no significant difference compared with losartan group. These findings indicated that Ang Ⅱ upregulated E-selectin and VCAM-1 in BMEC by activating AT1 receptor and then involved in the development of cerebrovascular disease.