蛇床子素改善慢性肾衰竭大鼠肾间质纤维化的机制研究

Study on the Mechanism of Osthole in Improving Renal Interstitial Fibrosis with Chronic Renal Failure in Rats

目的:研究蛇床子素(Osthole)对慢性肾功能衰竭(chronic renal failure,CRF)大鼠肾间质纤维化的抑制作用,并探讨其作用机制。方法:40只SPF级SD大鼠随机分为对照组、模型组和蛇床子素低、高剂量组,每组10只。利用腺嘌呤溶液连续灌胃21 d建立大鼠CRF模型,对照组给予等量的生理盐水。蛇床子素低、高剂量组分别腹腔注射给予10、20 mg/kg蛇床子素;连续治疗28 d。检测大鼠血清中肌酐(Scr)、尿素氮(BUN)及尿酸(UA)的水平变化;HE染色检测肾组织病理变化;ELISA法检测大鼠血清中基质金属蛋白酶(MMP-2、MMP-9)、组织金属蛋白酶抑制剂(TIMP-1、TIMP-2)水平;试剂盒检测超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量;Western Blot法检测肾组织中TGF-β、Smad2/3、p-Smad2/3、Smad4及Smad7蛋白的表达。结果:蛇床子素低、高剂量组大鼠血清Scr、BUN及UA含量明显低于模型组(P<0.05或P<0.01),并能显著改善大鼠肾组织损伤;蛇床子素能够降低TIMP-1、TIMP-2水平,增加MMP-2、MMP-9的水平(P<0.05或P<0.01);并能够降低肾脏组织中MDA含量,增加SOD活力(P<0.05或P<0.01);蛇床子素能显著降低TGF-β、Smad2/3、p-Smad2/3及Smad4蛋白表达,增加Smad7蛋白表达(P<0.05或P<0.01)。结论:蛇床子素对慢性肾衰竭大鼠的肾脏保护作用可能与调控TGF-β/Smad信号通路,抑制肾间质纤维化有关。

Objective:To investigate the effect of osthole on renal interstitial fibrosis with chronic renal failure(CRF)and its mechanism in rats.Methods:Forty SPF SD rats were randomly divided into control group,model group and the low and high dose osthole groups,10 rats in each group.The CRF rat model was established by continuous gavage of adenine solution for 21 days.The control group was given the same amount of normal saline.The low and high dose groups were respectively given intraperitoneal injection of 10 mg/kg and 20 mg/kg osthole;the treatment was continued for 28 days.The levels of creatinine(Scr),urea nitrogen(BUN)and uric acid(UA)in the serum of rats were detected;the pathological changes of renal tissue were stained by HE;the content of Matrix metalloproteinases(MMP-2 and MMP-9)and tissue inhibitors of metalloproteinases(TIMP-1 and TIMP-2)in serum was detected by ELISA;the activity of superoxide dismutase(SOD)and malondialdehyde(MDA)were detected by kit;the expressions of TGF-β,Smad2/3,p-Smad2/3,Smad4 and Smad7 were detected by Western Blot.Results:The low and high dose osthole groups showed lower serum levels of Scr,BUN and UA than model group(P<0.05 or P<0.01).The renal tissue injury was improved in rats of low and high dose osthole groups;Osthole reduced levels of TIMP-1 and TIMP-2 and increased levels of MMP-2 and MMP-9(P<0.05 or P<0.01);Osthole reduced the MDA content and increased the SOD activity in the kidney tissue(P<0.05 or P<0.01);Osthole reduced the expression of TGF-β,Smad2/3,p-Smad2/3 and Smad4 and increased the the expression of Smad7 significantly(P<0.05 or P<0.01).Conclusion:The protective effect of osthole on chronic renal failure may be related to the regulation of TGF-β/Smad signaling pathway and inhibition of renal interstitial fibrosis.