苦杏仁苷通过调节PI3K/Akt信号通路对先天性膈疝大鼠模型肺血管重构的影响

Effects of Amygdalinon Pulmonary Vascular Remodeling in Rats with Congenital Diaphragmatic Hernia by Regulating PI3K/Akt Signaling Pathways

目的观察苦杏仁苷对先天性膈疝(CDH)大鼠模型肺血管重构的影响,并探讨其作用机制。方法将配种后成功受孕的30只健康SD雌鼠随机分为对照组、模型组、苦杏仁苷低、中、高剂量组(10、20、40 mg/kg)和西地那非组,5只/组;采用100 mg除草醚灌胃诱导CDH模型;苦杏仁苷低、中、高剂量组及西地那非组于造模后给药,模型组和对照组给予等量生理盐水。于妊娠21.5 d,剖宫取胎鼠,观察CDH形成情况;采用HE染色观察胎鼠肺组织病理变化并分析肺小动脉中层血管壁厚度占肺小动脉外径的百分比(MT%)以及肺小动脉中层横截面积占总横截面积的百分比(MA%);Western blot检测胎鼠肺组织血管内皮生长因子(VEGF)、基质金属蛋白酶2(MMP-2)、基质金属蛋白酶9(MMP-9)、蛋白激酶B(Akt)、磷酸化蛋白激酶B(p-Akt)蛋白表达。结果与对照组比较,模型组胎鼠肺小动脉MT%、MA%均增加(均P<0.05),肺组织VEGF、MMP-2、MMP-9蛋白表达水平上调(均P<0.05),p-Akt/Akt比值升高(P<0.05)。与模型组比较,苦杏仁苷中、高剂量组及西地那非组胎鼠肺小动脉MT%、MA%均降低(均P<0.05);苦杏仁苷中、高剂量组胎仔肺组织VEGF、MMP-2、MMP-9蛋白表达水平下调(均P<0.05),p-Akt/Akt比值降低(P<0.05)。结论产前给予苦杏仁苷可能通过抑制PI3K/Akt信号通路激活从而改善CDH胎鼠肺血管重构。

Objective To observe the effects of amygdalin on pulmonary vascular remodeling in rats with congenital diaphragmatic hernia(CDH),and to explore its action mechanism.Methods A total of 30 healthy SD female mice with fertilization success were randomly divided into control group,model group,low-dose,medium-dose and high-dose amygdalin groups(10,20,40 mg/kg),and sildenafil group,5 cases in each group.Totally,100 mg of nitrofen was applied to induce CDH models by intragastric administration.After modeling,low-dose,medium-dose and high-dose amygdalin groups,and sildenafil group were administered,while model group and control group were given the same volume of normal saline.At 21.5 day after pregnancy,fetal rats were taken by cesarean section to observe the formation of CDH.The pathological changes of fetal lung tissues were observed by HE staining.The pulmonary arterial middle vascular wall thickness as a percentage of pulmonary arterial diameter(MT%)and pulmonary arterial middle cross-sectional area as a percentage of total cross-sectional area(MA%)were analyzed.The levels of vascular endothelial growth factor(VEGF),matrix metalloproteinase-2(MMP-2),matrix metalloproteinase-9(MMP-9),protein kinase B(Akt)and phosphorylated protein kinase B(p-Akt)in fetal lung tissues were detected by Western blotting.Results Compared with control group,MT%and MA%of fetal pulmonary arterioles were increased in model group(both P<0.05),expression levels of VEGF,MMP-2 and MMP-9 in lung tissues were significantly up-regulated(all P<0.05),and p-Akt/Akt was increased(P<0.05).Compared with model group,MT%and MA%of fetal pulmonary arterioles were decreased in medium-dose and high-dose amygdalin groups,and sildenafil group(all P<0.05),expression levels of VEGF,MMP-2 and MMP-9 in lung tissues were down-regulated in medium-dose and high-dose amygdalin groups(all P<0.05),and p-Akt/Akt was decreased(P<0.05).Conclusion Prenatal application of amygdalin may improve pulmonary vascular remodeling in rats with CDH by inhibiting the activation of PI3K/Akt signaling pathways.