芬戈莫德对血管紧张素Ⅱ灌注大鼠肾脏氧化应激的作用

Effect of Fingolimod on Angiotensin Ⅱ-induced Renal Oxidative Stress in Rats

目的研究芬戈莫德(FTY720)对血管紧张素Ⅱ(AngⅡ)灌注大鼠肾损伤的作用并探讨其可能机制。方法将36只SD雄性大鼠随机分为3组,每组12只:AngⅡ灌注组渗透性微量泵皮下泵入AngⅡ;0.9%氯化钠溶液灌注组渗透性微量泵皮下泵入等量0.9%氯化钠溶液;FTY720干预组在AngⅡ泵入基础上给予FTY720灌胃。每周收集各组大鼠24 h尿液,测定24 h尿蛋白含量,分别于第14天、第28天处死部分大鼠,留取血液及肾脏标本,试剂盒检测血及肾组织丙二醛(MDA)、总超氧化物歧化酶(T-SOD)含量;光镜观察各组肾组织病理学改变;免疫组织化学法检测肾还原型辅酶Ⅱ(NADPH)氧化酶4(Nox4)的表达及分布。结果与同期0.9%氯化钠溶液灌注组大鼠比较,第14天及第28天AngⅡ灌注组大鼠血肌酐、尿素氮、尿蛋白、血及肾组织AngⅡ、MDA含量显著增加(P<0.05),T-SOD活性显著降低(P<0.05),血清白蛋白下降,第28天差异有统计学意义(P<0.05)。与同期AngⅡ灌注组比较,第14天及第28天FTY720干预组大鼠血肌酐、尿素氮、尿蛋白、血及肾组织AngⅡ、MDA含量降低,T-SOD活性增加(P<0.05),血清白蛋白升高,第28天差异有统计学意义(P<0.05)。肾脏病理学观察显示,AngⅡ灌注组肾小球系膜细胞增生,系膜基质沉积,肾小管上皮细胞脱落,部分肾小球硬化、萎缩,FTY720干预组上述病理损伤部分缓解。免疫组化示,0.9%氯化钠溶液灌注组大鼠肾Nox4沿肾小管尤其是远端小管分布,AngⅡ灌注组Nox4表达显著增强,FTY720干预组Nox4表达减弱。结论 FTY720可通过减轻肾脏氧化应激改善AngⅡ灌注大鼠肾损伤。

Objective To evaluate the effect of fingolimod （ FTY720） on angiotensin n （ Ang Ⅱ ） -induced renal oxidative stress in rats and its possible mechanisms. Methods Thirty-six male Sprague-Dawley rats were divided into three groups through random number tables：AngⅡ infusion group（twelve rats,infusion of Angnvia subcutaneous osmotic pumps） ,0. 9% sodium hydrochloride solution infusion group（twelve rats,infusion of equal volume of 0.9% sodium hydrochloride solution via subcutaneous osmotic pumps） and FTY720 intervention group（twelve rats, intra-gastric administration of FTY720 besides AngH infusion）.Urine samples were collected for 24 hours every week. Blood samples and kidneys were collected when rats were sacrificed at day 14 and 28 d respectively.MDA and T-SOD assay Kits were used to detect the concentrations of MDA and T-SOD in serum and kidney homogenates.Renal pathological changes were observed by light microscope.The expression of Nox4 in the kidneys was evaluated by immunohistochemistry. Results Compared with 0.9% sodium hydrochloride solution infusion rats of the same period,Angn-inlused rats developed significant proteinuria.The concentration of serum creatinine,urea nitrogen,Angn and MDA were increased（ P 〈0 .0 5 ） ,T-SOD was significantly decreased on days 14 and 28（ P 〈 0 .0 5 ） ,the serum albumin was significantly increased on day 28（ P〈0.05） ,while FTY720 partially reversed these changes.The renal tissue of Ang Ⅱ -infused rats presented mesangial cells proliferation,mesangial matrix deposition,tubular epithelial cells effacement,sclerosis and atrophy in part of the glomemlar.FTY720 can alleviate these changes.Immunohistochemistry showed that Nox4 was primarily located in the distal tubule.The expression of Nox4 was significantly increased in Ang Ⅱ-infused rats as compared with that of 0.9% sodium hydrochloride solution infused group rats, and FTY720 administration prevented the change effectively. Conclusion Ang Ⅱ - induced renal injury could be attenuated by FTY720 via preventing oxidative stress.