糖尿病模型大鼠血液microRNA的表达特征及生物信息学分析

Expression characteristics and bioinformatics analysis of blood microRNAs in type 2 diabetes mellitus model rats

目的筛选2型糖尿病(T2DM)大鼠与正常大鼠血液中差异表达的microRNA(miRNA),通过生物信息学分析预测差异miRNA调控的靶基因及功能。方法取20只健康雄性SD大鼠随机分为空白对照组和T2DM模型组,每组10只。采用高脂饲料联合腹腔注射链脲佐菌素(STZ)制作T2DM大鼠模型,2周后提取糖尿病大鼠及正常大鼠全血,应用miRNA测序技术筛选差异miRNA。利用生物信息学方法对差异表达的miRNA靶基因进行基因本体(gene ontology,GO)和KEGG(Kyoto Encyclopedia of Genes and Genomes)通路富集分析。结果与空白对照组相比,T2DM模型组大鼠随机血糖均≥16.7 mmol/L且明显升高、持续稳定。与空白对照组相比,T2DM模型组大鼠血液中共有56个差异表达的miRNA,其中32个上调,24个下调。GO富集分析显示差异表达miRNA的靶基因主要集中在细胞质、细胞核、细胞膜等细胞组分,DNA及RNA的转录调控等生物学过程,与蛋白结合、金属离子结合、ATP结合等分子功能相关。KEGG通路富集分析显示差异表达miRNA的靶基因主要富集于糖尿病并发症、癌症等疾病通路,内吞、自噬等细胞功能通路,MAPK、mTOR、Ras、FoxO等信号通路。结论T2DM模型大鼠血液miRNA较正常大鼠差异表达变化明显,其差异表达的miRNA可能通过影响细胞的炎症免疫反应、增殖、生长分化等功能进而参与糖尿病及其并发症的发生发展。

Objective To screen differentially expressed microRNAs(miRNAs)in the blood of type 2 diabetes mellitus(T2DM)rats compared to normal rats,and predict the target genes and functions of the differentially expressed miRNAs through bioinformatics analysis.Methods Twenty healthy male SD rats were randomly divided into control group and T2DM model group,with 10 rats in each group.T2DM rat models were established by a high-fat diet and intraperitoneal injection of streptozotocin(STZ).After two weeks,the whole blood was collected from diabetic rats and normal rats to screen the differential miRNAs by miRNA sequencing technology.The target genes of differentially expressed miRNAs were analyzed by gene ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis.Results Compared with normal rats,the blood glucose was significantly increased(higher than 16.7 mmol/L)and kept stable in T2DM rats.Compared with normal rats,a total of 56 differentially expressed miRNAs were identified in the blood of T2DM model rats,including 32 upregulated and 24 downregulated miRNAs.GO enrichment analysis showed that the target genes of differentially expressed miRNAs were mainly concentrated in cellular components such as cytoplasm,nucleus,and cell membrane,biological processes such as transcriptional regulation of DNA and RNA,and molecular functions such as protein binding,metal ion binding,and ATP binding.The KEGG pathway enrichment analysis showed that the target genes of differentially expressed miRNAs were mainly enriched in diabetic complications,cancer-related pathways,cell functional pathways such as endocytosis and autophagy,and signal pathways such as MAPK,mTOR,Ras and FoxO.Conclusion Compared with normal rats,the blood miRNA expression profile of T2DM model rats is significantly altered.The differentially expressed miRNAs may affect cellular functions such as inflammation,immune response,proliferation,growth,thereby participating in the occurrence and development of T2DM.