MiR-132在大鼠肾间质纤维化模型中的表达及意义

Expression and significance of miR-132 in rat renal interstitial fibrosis model

目的分析miR-132在大鼠肾间质纤维化(RIF)模型中的表达情况,探讨其在RIF发生、发展中的可能机制。方法将24只大鼠随机分为假手术对照(sham)组和模型组,每组12只。模型组采用单侧输尿管结扎法建立大鼠RIF模型,sham组仅游离左侧输尿管而不结扎、切断输尿管。两组大鼠于术后第1、3天采用颈椎脱臼法分批处死,获取肾脏组织行Masson染色评估RIF。采用高通量测序检测模型组大鼠术后1、3d手术侧与非手术侧中miR-132的表达情况,采用实时荧光定量PCR检测术后1、3d模型组与sham组miR-132的相对表达量。应用Targetsan 5.1数据库预测miR-132的靶基因,对其进行Gene Ontology和Pathway分析,获得有显著意义的靶基因。结果sham组肾脏病理未见异常,模型组术后第1天肾间质基本正常,术后第3天肾间质轻度水肿,肾小球正常,提示早期RIF。模型组大鼠术后第1、3天手术侧肾组织miR-132表达上调。相对于sham组,模型组术后1、3d均miR-132表达上调。Gene Ontology和Pathway分析后获得9个显著意义靶基因,其中2个与上皮间质细胞转分化相关,2个参与细胞凋亡,1个与细胞外基质降解相关。结论在肾间质纤维化早期miR-132表达上调,miR-132可能通过激活上皮间质细胞转分化过程、参与细胞凋亡,减少细胞外基质蛋白降解等参与RIF的发生、发展。

Objective To investigate the expression of miR-132 in rat renal interstitial fibrosis(RIF)model and its significance.Methods Twenty four rats were randomly divided into sham operation control group and model group with 12 rats in each group.The renal interstitial fibrosis was induced by unilateral ureteral ligation in RIF model group and sham operation was performed in sham group.The rats were sacrificed in batches at 1 and 3 days after surgery,renal tissue was Masson stained to evaluate RIF.High-throughput sequencing was used to detect the expression of miR-132 on the surgical and non-surgical sides in rats of the model group 1 and 3 days after surgery.The relative expressions of miR-132 in the model group and sham group were detected by real-time quantitative PCR at 1 and 3 days after surgery.Target genes of miR-132 were predicted by Targetsan 5.1 database,and Gene Ontology and pathway analysis was conducted to obtain significant target genes.Results No abnormalities were found in renal pathology in sham group,the renal interstitium of the model group was basically normal at 1 day after surgery.The model group had mild interstitial edema and normal glomerulus at 3 days after surgery,suggesting early RIF.The expression of miR-132 increased in the renal tissue of operative side in model rats 1 day and 3 days after surgery.Compared with sham group,miR-132 expression in the model group was up-regulated at 1 and 3 days after surgery.Nine significant target genes of miR-132 were obtained,two of themwere associated with epithelial-mesenchymal transition(EMT),two of themwere involved in apoptosis,one of themwas related to extracellular matrix degradation.Conclusion In the early stage of RIF,miR-132 expression is up-regulated,miR-132 may be involved in the occurrence and development of RIF by activating the epithelial-mesenchymal transition process,promoting apoptosis,and inhibiting the degradation of extracellular matrix proteins.