迷迭香酸对子痫前期大鼠炎症和内皮功能障碍的影响

Effects of rosmarinic acid on inflammation and endothelial dysfunction in preeclampsia rats

目的 探究迷迭香酸(RA)对子痫前期(PE)大鼠的治疗作用及机制。方法 从孕第11天开始,对孕鼠连续4 d每天皮下注射左旋硝基精氨酸甲酯(L-NAME,200 mg/kg)建立PE大鼠模型,将30只成功建模的大鼠随机分为3组:模型组、50RA组(50 mg/kg RA)和100RA组(100 mg/kg RA),每组10只。另选10只同期孕鼠作为对照组。孕第15天时,50RA组和100RA组大鼠灌胃不同浓度RA,对照组和模型组大鼠灌胃等体积生理盐水,连续灌胃7 d。孕第21天时,检测各组大鼠的收缩压(SBP)、24 h尿蛋白、胎鼠体质量和死亡率,并对胎盘组织进行苏木精-伊红(HE)染色,对肾脏组织进行过碘酸-雪夫(PAS)染色。按照试剂盒说明检测大鼠血清超氧化物歧化酶(SOD)和丙二醛(MDA)水平。使用ELISA试剂盒检测大鼠血清中细胞因子白细胞介素(IL)-1β、IL-6、干扰素-γ(IFN-γ)和单核细胞趋化蛋白(MCP)-1的水平。通过Western blot检测胎盘组织中细胞间黏附分子-1(ICAM-1)、白细胞功能相关抗原(LFA-1)、血管细胞黏附分子-1(VCAM-1)、Toll样受体4(TLR4)和髓样分化因子88(MyD88)的蛋白表达水平。结果 与对照组相比,模型组大鼠的SBP和24 h尿蛋白水平升高(P<0.05),胎鼠体质量降低(P<0.05),胎鼠死亡率升高(P<0.05),胎盘和肾脏组织出现明显损伤,血清SOD水平降低(P<0.05),MDA水平升高(P<0.05),血清IL-1β、IL-6、IFN-γ和MCP-1水平升高(P<0.05),胎盘组织中ICAM-1、LFA-1、VCAM-1、TLR4和MyD88的蛋白表达水平升高(P<0.05)。与模型组相比,50RA组和100RA组大鼠的SBP和24 h尿蛋白水平均降低(P<0.05),胎鼠体质量均升高(P<0.05),胎鼠死亡率均降低(P<0.05),胎盘和肾脏组织形态明显改善,血清SOD水平均升高(P<0.05),MDA水平均降低(P<0.05),血清IL-1β、IL-6、IFN-γ和MCP-1水平均降低(P<0.05),胎盘组织中ICAM-1、LFA-1、VCAM-1、TLR4和MyD88的蛋白表达水平均降低(P<0.05)。与50RA组相比,100RA组大鼠的SBP和24 h尿蛋白水平降低(P<0.05),胎鼠体质量升高(P<0.05),胎盘和肾脏组织形态明显改善,血清SOD水平升高(P<0.05),MDA水平降低(P<0.05),血清IL-1β、IL-6、IFN-γ和MCP-1水平降低(P<0.05),胎盘组织中ICAM-1、LFA-1、VCAM-1、TLR4和MyD88的蛋白表达水平降低(P<0.05)。结论 RA有效减轻了PE大鼠的病理改变,RA可能通过减轻TLR4信号通路介导的炎症、氧化应激和内皮功能障碍来发挥其对PE的治疗作用。

Objective To explore the therapeutic effect and its mechanism of rosmarinic acid(RA)on preeclampsia(PE)rats.Methods Starting from the 11th day of pregnancy,pregnant rats were subcutaneously injected with L-nitroarginine methyl ester(L-NAME,200 mg/kg)every day for four consecutive days to establish a PE rat model,and then 30 model rats were randomly divided into three groups:model group,50RA group and 100RA group,with 10 rats in each group.Another 10 pregnant rats were selected as control group.At pregnant day 15,the rats in 50RA group and 100RA group were given 50 mg/kg RA and 100 mg/kg RA by gavage,respectively,and the rats in control group and model group were given normal saline by gavage for seven consecutive days.At pregnant day 21,systolic blood pressure(SBP),24 h urine protein,fetal body weight and mortality in each group were detected,the placental tissue was stained with hematoxylin-eosin(HE),and the kidney tissue was stained with periodic acid-Schiff(PAS)staining.Superoxide dismutase(SOD)and malondialdehyde(MDA)levels in serum of rats were detected with the kits.The serum levels of interleukin(IL)-1β,IL-6,interferon-γ(IFN-γ)and monocyte chemoattractant protein-1(MCP-1)in rats were detected using ELISA kits.Western blot was used to detect protein expressions of intercellular adhesion molecule-1(ICAM-1),leukocyte function-related antigen-1(LFA-1),vascular cell adhesion molecule-1(VCAM-1),Toll-like receptor 4(TLR4)and myeloid differentiation factor 88(MyD88).Results Compared with control group,SBP and 24 h urinary protein levels were increased in model group(P<0.05),fetal body weight was decreased(P<0.05),fetal mortality was increased(P<0.05),there was significant damages in placenta and kidney tissue,serum level of SOD was decreased(P<0.05),MDA level was increased(P<0.05),serum IL-1β,IL-6,IFN-γand MCP-1 levels were increased(P<0.05),and the protein expression levels of ICAM-1,LFA-1,VCAM-1,TLR4 and MyD88 in placental tissue were increased(P<0.05).Compared with model group,SBP and 24 h urinary protein levels were decreased in 50RA group and 100RA group(P<0.05),fetal body weight was increased(P<0.05),fetal mortality was decreased(P<0.05),the damages of placenta and kidney tissues were significantly improved,serum level of SOD was increased(P<0.05),MDA level was decreased(P<0.05),serum IL-1β,IL-6,IFN-γand MCP-1 levels were decreased(P<0.05),and the protein expressions of ICAM-1,LFA-1,VCAM-1,TLR4 and MyD88 in placental tissue were decreased(P<0.05).Compared with 50RA group,SBP and 24 h urinary protein levels were decreased in 100RA group(P<0.05),fetal body weight was increased(P<0.05),the damages of placenta and kidney tissues were significantly improved,serum level of SOD was increased(P<0.05),MDA level was decreased(P<0.05),serum IL-1β,IL-6,IFN-γand MCP-1 levels were decreased(P<0.05),and the protein expressions of ICAM-1,LFA-1,VCAM-1,TLR4 and MyD88 in placental tissue were decreased(P<0.05).Conclusion RA can effectively alleviate the pathological changes of PE rats,and RA may exert its therapeutic effect on PE by reducing inflammation,oxidative stress and endothelial dysfunction mediated by TLR4 signaling pathway.