大鼠肾脏56切除microRNA-483-3p的表达变化及机制

MicroRNA-483 expression changes and mechanism in kidney of 5/6 nephrectomy rats

目的探讨慢性肾脏疾病中microRNA-483-3p及其相关靶基因表达情况,明确过表达miR-483-3p的治疗效果。方法大鼠分为对照组(假手术组,12只),模型组(5/6肾切除组,12只),miR-483-3p过表达组(5/6肾切除+miR-483-3p Agomir,12只)3组。miR-483-3p Agomir给予60mg/kg尾静脉注射,每两周一次。末次术后8周处死大鼠。测定血生化指标,使用ELISA方法测血清中hs-CRP及24小时尿蛋白含量;采用RT-PCR方法进一步筛查出miR-483-3p的下游靶基因;用RT-PCR和Western Blot方法测定三组大鼠肾组织中miR-483-3p及其靶基因表达变化。同时RT-PCR方法测定miR-483-3p宿主基因TGF-2的表达变化。结果与对照组相比,模型组BUN、Cr明显升高,TC及LDL-C亦显著升高。干预组较模型组BUN、Cr明显降低,血脂水平治疗前后无明显变化。hs-CRP及24小时尿蛋白定量在模型组明显升高,干预组显著降低。RT-PCR结果显示与对照组相比,模型组肾脏组织中CTGF和EGFR/PTEN表达显著升高,而TGF-β、DPC4/Smad4及AANAT无明显变化。干预组较模型组表达显著降低。模型组较对照组肾脏组织中IGF-2的表达明显升高,干预组肾脏组织IGF-2的表达较模型组表达显著降低。结论慢性肾脏疾病,miR-483-3p表达增加,通过抑制其靶基因CTGF、PTEN的表达,可延缓肾脏纤维化过程。

Objective To investigate the expression of microRNA-483-3p and its related target genes in chronic kidney diseases and determine the therapeutic effect of overexpression of mir-483-3p.Methods The rats were 5/6 nephrectomized to establish animal models.Then were divided into control group,model group and Mir-483-3p overexpression group.Mir-483-3p Agomir was injected into the tail vein at 60mg/kg once every two weeks.The rats were sacrificed 8 weeks after the last operation.Serum hs-CRP and 24-hour urine protein were determined by ELISA.The downstream target genes of mir-483-3p were further screened by RT-PCR.Expression changes of mir-483-3p and its target gene in renal tissues were determined by RT-PCR and Western Blot.Meanwhile,the expression of mir-483-3p host gene IGF-2 was determined by RT-PCR.Results Compared with the control group,the level of BUN,Cr,TC and LDL-C were significantly increased in the model group.BUN and Cr in the intervention group were significantly lower than those in the model group.Hs-CRP and 24-hour urine protein quantification increased significantly in the model group,but decreased significantly in the intervention group.RT-PCR results showed that compared with the control group,the expression of CTGF and EGFR/PTEN in the kidney tissues were significantly increased,while TGF-β,DPC4/Smad4 and AANAT were not significantly changed.The expression of CTGF and EGFR/PTEN in the intervention group was significantly lower than in the model group.The expression of IGF-2 in the model group was significantly higher than that in the control group,while the expression of IGF-2 in the intervention group was lower than that in the model group(P=0.0583).Conclusion Mir-483-3p is increased in chronic kidney disease,which can delay the process of renal fibrosis by inhibiting the expression of CTGF and PTEN.