基于AngⅡ/TLR4/NF-κB通路探讨滋阴潜阳方改善自发性高血压大鼠肾损害的机制

Mechanism of Action of Ziyin Qianyang Prescription in Improving Renal Injury in Spontaneously Hypertensive Rats:A Study Based on the AngⅡ/TLR4/NF-κB Pathway

目的观察滋阴潜阳方对自发性高血压大鼠(spontaneously hypertensive rat,SHR)肾脏血管紧张素Ⅱ(angiotensinⅡ,AngⅡ)/Toll样受体4(toll-like receptor 4,TLR4)/核转录因子-κB(nuclear transcription factor-κB,NF-κB)信号通路的干预作用,探讨其改善SHR肾脏损害的机制。方法将40只雄性SHR随机分为模型组,依那普利组,滋阴潜阳方低、高剂量组,每组10只。各组连续灌胃6周,每日2次。每2周测量大鼠收缩压值,给药6周后,采用ELISA法检测大鼠血清中AngⅡ、血管紧张素(1-7)angiotensin 1-7,Ang(1-7)水平;苏木精-伊红染色法观察SHR肾组织结构等变化;RT-PCR检测大鼠肾组织中TLR4 mRNA、NF-κB p65 mRNA表达水平。结果与模型组比较,各药物干预组收缩压、AngⅡ水平以及TLR4、NF-κB p65 mRNA表达水平均呈现不同程度的降低,血清Ang(1-7)水平显著提高(P<0.05);与滋阴潜阳方低剂量组比较,滋阴潜阳方高剂量组收缩压、AngⅡ含量及TLR4、NF-κB p65 mRNA表达水平显著降低,Ang(1-7)水平显著升高(P<0.05)。苏木精-伊红染色结果提示:模型组肾组织形态严重受损,滋阴潜阳方高剂量组及依那普利组肾脏损害程度较轻并有一定改善。结论滋阴潜阳方能够有效降低SHR血压,减轻和改善高血压引起的肾脏炎症损害,其机制可能与抑制AngⅡ/TLR4/NF-κB通路从而降低炎症因子表达水平有关。

Objective To investigate the interventional effect of Ziyin Qianyang prescription on the renal angiotensinⅡ(AngⅡ)/Toll-like receptor 4(TLR4)/nuclear transcription factor-κB(NF-κB)signaling pathway in spontaneously hypertensive rats(SHRs),as well as its mechanism of action in improving renal injury in SHRs.Methods A total of 40 male SHRs were randomly divided into model group,enalapril group,and low-and high-dose Ziyin Qianyang prescription groups,with 10 rats in each group.Each group was given intragastric administration twice a day for 6 weeks.Systolic pressure was measured every two weeks.After 6 weeks of administration,ELISA was used to measure the serum levels of AngⅡand angiotensin 1-7[Ang(1-7)],HE staining was used to observe the changes of renal tissue structure,and RT-PCR was used to measure the mRNA expression levels of TLR4 and NF-κB p65 in renal tissue.Results Compared with the model group,all drug intervention groups had varying degrees of reduction in systolic pressure,AngⅡlevel,and the mRNA expression levels of TLR4 and NF-κB p65 and a significant increase in the serum level of Ang(1-7)(P<0.05).Compared with the low-dose Ziyin Qianyang prescription group,the high-dose Ziyin Qianyang prescription group had significant reductions in systolic pressure,AngⅡlevel,and the mRNA expression levels of TLR4 and NF-κB p65 and a significant increase in the level of Ang(1-7)(P<0.05).HE staining showed that the model group had severe damage of renal histomorphology,and the high-dose Ziyin Qianyang prescription group and the enalapril group had mild damage and certain improvement.Conclusion Ziyin Qianyang prescription can effectively reduce blood pressure and alleviate and improve renal inflammatory damage caused by hypertension in SHRs,possibly by inhibiting the AngⅡ/TLR4/NF-κB pathway and thus reducing the expression levels of inflammatory factors.