Necrostatin-1对急性肾小管坏死大鼠的保护机制

摘要

目的 观察Necrostatin-1(坏死性凋亡特异性抑制剂,Nec-1)对急性肾小管坏死(ATN)大鼠的保护作用,并对其作用机制进行分析.方法 选取45只SD雄性大鼠,采用肌肉注射甘油的方法制作ATN动物模型,随机分为Nec-1低剂量组、Nec-1高剂量组和模型组,每组15只;另选15只大鼠作为对照组.Nec-1低剂量组和高剂量组大鼠分别给予0.4 mg/kg和0.8 mg/kg Nec-1(二甲基亚砜溶解)尾静脉注射,模型组和对照组注射等体积二甲基亚砜.分别对各组大鼠血肌酐(Scr)、血尿素氮(BUN)和肾功能衰竭指数(RFI)进行分析;采用ELISA法检测各组大鼠肾脏组织中肿瘤坏死因子-α (TNF-α)和白细胞介素-1β(IL-1β)水平;采用Western blot方法检测受体相互作用蛋白1和3(RIP1,RIP3)的表达;苏木精伊红(HE)染色观察分析肾脏组织病理学变化.结果 与对照组比较,模型组、Nec-1低剂量组和高剂量组大鼠Scr水平、BUN水平以及RFI显著升高(P＜0.05),肾脏组织中TNF-α、IL-1β、RIP1以及RIP3水平显著升高(P＜0.05).与模型组大鼠比较,Nec-1低剂量组和高剂量组大鼠Scr水平、BUN水平以及RFI显著下降(P＜0.05),肾脏组织中TNF-α、IL-1β、RIP1以及RIP3水平显著下降(P＜0.05).病理结果显示,与对照组比较,模型组、Nec-1低剂量组和高剂量组大鼠肾脏均不同程度增大,肾小管变形明显,管腔中蛋白管型增多,且模型组大鼠病理变化较Nec-1低剂量组和高剂量组显著(P＜0.05);其中,低剂量和高剂量组大鼠各项指标的变化均呈剂量依赖性.结论 Necrostatin-1能够有效改善急性肾小管坏死大鼠Scr、BUN水平及RFI,起到保护肾脏损伤的作用,其机制可能与抑制体内炎症因子水平和细胞程序性坏死相关.%Objective To observe the protective effect of Necrostatin-1 on acute tubular necrosis (ATN) rats,and to analyze the mechanism.Methods Forty-five SD male rats were enrolled to prepare ATN aninal model by intramuscular injection of glycerol production,and they were randomly divided into model group,low dose group and high dose group,with 15 rats in each group.Fifteen normal rats were selected as control group.Rats in low dose group and high dose group were given 0.4 mg/kg and 0.8 mg/kg Nec-1 (dissolved in DMSO) by tail vein.Rats in model group and control group were injected with equal DMSO.Serum creatinine (Scr),blood urea nitrogen (BUN) and renal failure index (RFI) were analyzed.Tumor necrosis factor alpha (TNF-α) and interleukin-1 β (IL-1 β) levels in peripheral blood were detected by ELISA method.Receptor interacting protein 1 (RIP1) and receptor interacting protein 3 (RIP3) were detected by Western blot.Pathological changes of kidney were observed and analyzed by HE stain.Results Compared with control group,Scr level,BUN level and RFI of rats in model group,low dose group and high dose group were increased significantly (P ＜ 0.05),TNF-α,IL-1 β,RIP1 and RIP3 levels in kidney tissues of rats were increased significantly (P ＜ 0.05).Compared with model group,Scr level,BUN level and RFI of rats in low dose group and high dose group were decreased significantly (P ＜ 0.05),TNF-α,IL-1 β,RIP1 and RIP3 levels in kidney tissues of rats were decreased significantly (P ＜ 0.05).Compared with control group,pathological results showed that the kidney grew in varying degrees,renal tubular deformed obviously,protein tube type in lumen increased in model group,low dose group and high dose group.The pathological change of rats in model group were more significant than that of low dose group and high dose group (P ＜ 0.05).The changes of each index of the low dose and high dose group were dose dependent.Conclusions Necrostatin-1 can effectively improve Scr,BUN level and RFI of rats with acute renal tubular necrosis.It plays a role in protecting the kidney with the mechanism of the inhibition of the levels of inflammatory factors and programmed cell necrosis.