连黄降浊颗粒对自发性高血压大鼠肾组织TGF-β_1/smads信号传导通路的影响

Effect of Lianhuang Turbid Clearance Granules on TGF-β_1/ smads Signaling Pathway of Kidney in Spontaneous Hypertension Rats

目的:观察连黄降浊颗粒对自发性高血压大鼠(spontaneous hypertension rat,SHR)肾组织转化生长因子(transforming growth factor,TGF)-β_1/smads信号传导通路的影响。方法:雄性10周龄SHR40只,按体重随机分为4组:模型组、苯那普利对照组(对照组)、连黄降浊颗粒低剂量组(低剂量组)、连黄降浊颗粒高剂量组(高剂量组)各10只,采取切除所有大鼠右肾的方法制备高血压性肾损害模型。另取10只同周龄Wistar-Kyoto(WKY)大鼠同样切除右肾,作为正常血压对照组(WKY组)。造模1周后给予相应浓度和剂量的药物。给药第4周、8周末观察大鼠尿微量白蛋白(m Alb)、尿微量白蛋白与尿肌酐比值(m Alb/Ucr)和血清肌酐(Scr)。于第8周末处死所有动物,取其肾组织行HE染色、PAS染色和Masson染色,观察病理变化并半定量计算肾小管损伤指数(tubulointerstitial injury index,TII),免疫组化法检测骨形成蛋白-7(bone morphogenetic protein,BMP-7)、TGF-β_1、smad2、smad7在肾组织的表达。结果:造模1周以及给药第4周、第8周,4组SHRm Alb、m Alb/UCr、Scr随时间延长呈逐渐升高趋势,且差异均与WKY组差异有统计学意义(P<0.01),而给药前4组SHR之间上述指标差异均无统计学意义(P>0.05)。给药4周后,SHR中3个治疗组m Alb、m Alb/UCr、Scr显著低于模型组(P<0.05),高剂量组明显低于对照组(P<0.05)。8周时组间比较,低剂量组、高剂量组SHR上述指标明显低于对照组(P<0.05),高剂量组低于低剂量组(P<0.05)。HE染色、PAS染色显示WKY组大鼠肾组织形态大致正常。HE染色显示,3个治疗组SHR肾组织损害较模型组明显减轻,高剂量组病理改善更明显。PAS染色进行TII评分发现,3个治疗组大鼠TII显著低于模型组(P<0.05),高剂量组明显低于模型组和低剂量组(P<0.05)。TGF-β_1和Smad2在WKY组呈无或弱阳性,而BMP-7和Smad7呈强阳性表达。与模型组相比,TGF-β_1、Smad2在3个治疗组大鼠肾组织的表达下调(P<0.05),2个中药治疗组大鼠肾组织的表达低于对照组(P<0.05);3个治疗组BMP-7、smad7在肾脏组织的表达上调(P<0.05),2个中药治疗组大鼠肾组织的表达高于对照组(P<0.05)。结论:连黄降浊颗粒可能通过干预BMP-7/TGF-β_1/Smads信号转导通路抑制了TGF-β_1在肾组织的表达,而对SHR肾间质纤维化起到了治疗作用。

Objective：To observe the effects of Lianhuang turbid clearance granules（LHTCG） on TGF - β1/stnadssignaling pathway of kidney in spentaneously hypertensive rats（SHR）. Methods：40 male SHR of 10 weeks oldwere randomly divided into 4 groups according to the bodyweight （n = 10） ： model group, benazepril group （control group） , low -dose LHTCG group （low-dose group）, highdose LHTCG group （high -dose group）. And then the model of hypertensive kidney damaged rats was prepared by the method of resecting the right kidneys of all rats under aseptic conditions. Other10 Wistar- Kyoto（ WKY ） ratsof the saute weeks old were equally removed right kidney as the normal blood pressure control group （WKY group）. After one week, the drugs of corresponding concentration and doses were administered to the rats. They were examedformicroalbumin （mAlb） , urinary microalbumin to creatinine（ mAlb/Ucr）, serum creatiuine（Scr） and urea nitrogen（BUN） after administration ior 4 weeks and 8 weeks. And then, all rats were sacrificed. Histological changes in kidney tissues were examined by HE, PAS and Masson stain. The protein expression of BMP -7,TGF-β1 ,Smad2,Smad7 in kidney tissues were detected by ELISA respectively. Results： mAlb, mAlb/UCr, Scr of 4 SHR groups were increased gradually with time ＇after modeled 1 th week, administrated4th and 8th week. Their date compared with the W KY group had statistical significance （P 〈 0.01 ）, but had no statistical significance existed between the groups of SHR （P〉 0.05 ）. At4th week, the mAlb, mAlb/UCr and Scr of 3 treatment groups of SHR were significantly lower than that of model group （P 〈0.05 ）, the figures of the high - dose group was significantly lower than that of control group （ P 〈 0.05）. At 8th week, the data of low - and high - dose groups was significantly lower than that in the control group （ P 〈 0.05 ）, and the high - dose group was more obvious than low - dose one （P 〈 0.05 ）. Histological of WKY rats was normal in HE and PAS staining. HE staining showed that the damageof kidney tissue in the 3 treatment groups of SHR was significantly higher than that in the model group, and the pathological changes were more obvious in high - dose group. PAS staining showed that the TII score of 3 treatment SHR groups was significantly lower than the data of model group （ P 〈 0.05 ）. The high - dose group was significantly lower than the model group and low - dose group （ P 〈 0.05）. TGF- β1 and Smad2 in group WKY showed no or weak positive, while BMP-7 and Smad7 showed strong positive expres- sion. Compared with the model group, TGF - β1, Smad2 in kidney tissues of the 3 treatment groups of SHR expressed reduced （P 〈 0.05 ） and the expression in low - and high - dose groups less than control group （ P 〈 0.05 ） ; BMP - 7 and Smad7 expression raised in kidney tissue of control group , low - and high - dose groups （P 〈 0.05）, the two Chinese medicine treatment groups higher than that of the control group （P 〈 0.05 ）. Conclusion：The LHTCG may through intervene the BMP -7/TGF - β1/Smads signal transduction pathway to inhibit the expression of TGF - β1 in kidney tissues, and obtain a therapeutic effect for SHR in kidney interstitial fibrosis.