莱菔硫烷减轻肾缺血再灌注大鼠肝损伤

Sulforaphane attenuates liver injury in rats with renal ischemia-reperfusion

目的:观察莱菔硫烷(SFN)对肾缺血再灌注损伤(RIRI)大鼠肝组织形态、功能、过氧化损伤及超氧化物歧化酶(SOD)表达变化的影响。方法:Wistar大鼠随机分对照组、RIRI组、SFN1组和SFN2组,RIRI组大鼠用夹闭左肾动脉45 min的方法建立RIRI模型,SFN1组在夹闭左肾动脉后立即给予SFN,SFN2组在RIRI模型恢复血液再灌注后给予SFN,对照组大鼠只分离左肾动脉并不夹闭。缺血再灌注24 h后取血和肝,检测血清谷丙转氨酶(ALT)活性;采用钼酸比色法、硫代巴比妥酸比色法及黄嘌呤氧化酶法测定肝组织H2O2、丙二醛(MDA)含量及SOD活性;H-E染色观察肝组织形态结构改变;Real-time PCR和免疫印迹法分别测定肝组织SOD mRNA和蛋白表达水平。结果:与对照组相比,RIRI组、SFN1组和SFN2组大鼠肝组织形态结构受损明显,SFN1组和SFN2组受损程度轻于RIRI组,SFN1组又略轻于SFN2组;RIRI组、SFN1组和SFN2大鼠血清ALT活性、肝组织MDA和H2O2含量升高明显;SFN1组和SFN2组的活性和含量均低于RIRI组,SFN1组又低于SFN2组;RIRI组、SFN1组和SFN2大鼠肝组织SOD活性明显低于对照组,SFN2组、SFN1组高于RIRI组,SFN1组又高于SFN2组。RIRI组、SFN1组、SFN2组大鼠肝组织SOD mRNA和蛋白表达水平均高于对照组,SFN2组和SFN1组SOD的表达水平又高于RIRI组,但SFN2组和SFN1组差异无统计学意义。结论:大鼠RIRI发生后,SFN可能通过上调SOD的表达增强机体对过氧化物的清除作用,降低了肝组织过氧化损伤程度;与再灌注后给予SFN相比,缺血后即刻给药更能有效降低肝组织氧化应激水平,改善肝的形态结构和功能改变。

Objective:To observe the effect of sulforaphane(SFN)on the changes of liver morphology,function,peroxidation damage and SOD expression in rats with renal ischemia-reperfusion injury(RIRI).Methods:Wistar rats were randomly divided into control group,RIRI group,SFN1 group and SFN2 group.RIRI models of RIRI,SFN1 and SFN2 group were established by clamping the left renal artery for 45 minutes.The rats of SFN1 group were given sulforaphane immediately after clamping the left renal artery.The rats of SFN2 group were given sulforaphane after restoring blood perfusion.In the control group,the left renal artery was separated and not occluded.The blood and liver were taken after reperfusion for 24 hours.The activities of ALT in serum were detected.The MDA,H2O2 content and the SOD activity in the liver were detected by thiobarbituric acid colorimetric,spectrophotometric and xanthine oxidase method respectively.The morphological structure of the liver was observed by HE staining.The expression level of SOD mRNA and protein in the liver were evaluated by Real-time PCR and Western blotting respectively.Results:Compared with the control group,the morphological structure of the liver of rats in RIRI,SFN1 and SFN2 group was significantly impaired.The damages degrees of SFN1 and SFN2 group were lower than that of RIRI group.SFN1 group had slightly lower degree of damage than SFN2 group.The ALT activity in serum,MDA and H2O2 content in the liver of rats in RIRI,SFN1 and SFN2 group were significantly higher than that of control group,SFN1,and SFN2 group was lower than RIRI group and SFN1 group was lower than SFN2 group in the ALT activity.The SOD activity in the liver of RIRI,SFN1 and SFN2 group was significantly lower than that of control group.SFN1 and SFN2 group had higher SOD activity than RIRI group,and SFN1 group was higher than SFN2 group in SOD activity.The expression levels of SOD mRNA and protein in the liver of rats from RIRI,SFN1 and SFN2 group were higher than that of control group,and the SOD expression levels of SFN1 and SFN2 group were higher than that of RIRI group.However,there was no significant difference between SFN2 group and SFN1 group.Conclusion:After renal ischemia-reperfusion injury,sulforaphane enhances scavenging of peroxide and reduces the degree of peroxidation injury of the liver by upregulating Nrf2-downstream-gene SOD expression.Compared with administration of sulforaphane after reperfusion,immediate administration after ischemia could effectively reduce oxidative stress level and improve morphological and functional change of the liver.