基于TGF-β1/Smad通路探讨红花黄色素对腺嘌呤致肾间质纤维化大鼠的保护作用

Study on the Protective Effect of Safflor Yellow on Adenine Induced Renal Fibrosis Rats Based on TGF-β1/Smad Pathway

目的观察红花黄色素对腺嘌呤致肾间质纤维化大鼠的保护作用及其对转化生长因子β1(TGF-β1)/Smad信号通路的影响。方法采用腺嘌呤(250 mg·kg^(-1))灌胃建立肾纤维化大鼠模型。将SD大鼠随机分为对照组、模型组、氯沙坦组(9 mg·kg^(-1))及红花黄色素低、高剂量组(9、18 mg·kg^(-1)),每组10只,灌胃给药,每天1次,连续30 d。检测大鼠血清肌酐(Cr)、尿素氮(BUN)含量;采用HE和Masson染色法观察大鼠肾脏组织病理学变化;采用RT-qPCR法检测大鼠肾组织中TGF-β1、Smad4及Smad7 mRNA表达情况;采用免疫组化法及Western Blot法检测大鼠肾组织中TGF-β1、Smad4及Smad7蛋白表达情况。结果与对照组比较,模型组大鼠血清Cr、BUN含量显著升高(P<0.01);大鼠肾脏组织中TGF-β1 mRNA及蛋白表达水平明显升高(P<0.05),Smad7 mRNA及蛋白表达水平明显下降(P<0.05)。与模型组比较,各给药组大鼠血清Cr、BUN水平明显降低(P<0.05,P<0.01);各给药组大鼠肾脏组织中TGF-β1 mRNA及蛋白表达水平明显降低(P<0.05),Smad7 mRNA及蛋白表达水平明显升高(P<0.05)。各组大鼠肾脏组织中Smad4 mRNA及蛋白表达水平无明显变化(P>0.05)。结论红花黄色素对腺嘌呤致肾间质纤维化大鼠具有保护作用,其机制可能与抑制TGF-β1/Smad信号通路有关。

Objective To observe the protective effect of safflower yellow on adenine induced renal fibrosis rats and its influence on the TGF-β1/Smad signaling pathway.Methods A rat model of renal fibrosis was established by gavaging of 250 mg·kg^(-1) of adenine.SD rats were randomly divided into normal control group,renal fibrosis model group,losartan group(9 mg·kg^(-1)),safflor yellow low and high dose groups(9,18 mg·kg^(-1)),with 10 rats in each group.Gavage was given once a day for 30 consecutive days.The serum creatinine(Cr)and urea nitrogen(BUN)were measured.The histopathological changes of rats’kidney were observed by HE and Masson staining.RT-qPCR method was used to detect the expression of TGF-β1,Smad4 and Smad7 mRNA in rat kidney tissue;immunohistochemical method and Western Blot method were used to detect TGF-β1,protein expression of Smad4 and Smad7 in rats’kidney tissue.Results Compared with the control group,the serum Cr and BUN levels in the model group were significantly increased(P<0.01);the TGF-β1 mRNA and protein expression levels in the rats’kidney tissue were significantly increased(P<0.05),and Smad7 mRNA and protein expression levels were significantly decreased(P<0.05).Compared with the model group,the serum Cr and BUN levels of rats in each administration group were significantly reduced(P<0.05,P<0.01);the expression levels of TGF-β1 mRNA and protein in the kidney tissue of rats in each administration group were significantly reduced(P<0.05),Smad7 mRNA and protein expression levels were significantly increased(P<0.05).There was no significant change in the expression levels of Smad4 mRNA and protein in the kidney tissues of rats in each group(P>0.05).Conclusion Safflor yellow has protective effect on adenine-induced renal interstitial fibrosis in rats,and its mechanism may be related to the inhibition of TGF-β1/Smad signaling pathway.