高脂饮食诱导的肥胖相关子宫内膜病变小鼠模型中circRNA表达谱分析及相关ceRNA构建

CircRNA expression profile analysis and related ceRNA construction in a mouse model of obesity-related endometrial lesions induced by high fat diet

目的探索高脂饮食喂养构建的肥胖小鼠子宫内膜病变模型中mRNA、环状RNA(circRNA)转录谱改变情况;并通过构建差异表达circRNA相关的竞争性内源性RNA(ceRNA)调控网络,探讨在肥胖诱导子宫内膜病变中可能的cicrRNA调控机制。方法6周龄CD-1(ICR)雌鼠随机分为正常热量饮食组、17β-雌二醇(E2)组、高脂饮食(HFD)组及HFD+E2组,构建高脂饮食诱导小鼠子宫内膜病变模型,HE染色鉴定各组小鼠子宫内膜病变发生情况;高通量RNA测序(RNA-seq),筛选差异表达circRNA,lncRNA及mRNA。并收集人子宫内膜癌组织和正常子宫内膜组织,利用实时定量逆转录PCR验证测序结果。结果HFD组干预26周后小鼠子宫内膜均出现增生改变,且子宫内膜非典型增生发生率与E2组小鼠相似(25%vs 16.7%)。HFD干预13周和26周均诱导小鼠子宫内膜的mRNA、cicrRNA转录谱出现显著改变;GO和KEGG分析的结果显示高脂饮食诱导的差异表达mRNA主要富集于免疫反应、细胞周期、Wnt信号通路及代谢过程。生信分析成功构建circRNA-miRNA-mRNA的ceRNA网络。结论高脂饮食构建的肥胖小鼠子宫内膜病变模型中存在RNAs转录本显著改变,并有可能改变子宫内膜的稳态;而相关cicrRNA的ceRNA调控网络在肥胖相关子宫内膜病变中的作用值得进一步研究。

Objective:To explore the changes of mRNA and circle RNA(circRNA)transcriptional profile during the development of endometrial lesions induced by high fat diet in mice.A competitive endogenous RNA network associated with differential expression of circRNA was constructed to explore the possible mechanism of cicrRNA regulation in endometrial lesions induced by high fat diet.Methods:Six weeks of CD-1(ICR)female rats were randomly assigned to normal calorie diet group(control group),17β-estradiol(E2)group,high fat diet(HFD)group and HFD+E2 group.The endometrial lesion model of mice induced by high-fat diet and or E2 was constructed.HE staining was used to identify the occurrence of endometrial lesion in each group.High-throughput RNA sequencing(RNA-seq)was performed to screen differentially expressed circRNA,lncRNA and mRNA.The accuracy of the RNA-seq was verified by real-time quantitative reverse transcription PCR(qRT-PCR)in 10 human endometrial carcinoma tissues and 10 normal endometria.Results:Endometrial hyperplasia was observed in mice in HFD group after 26 weeks of intervention,and the incidence of endometrial atypical hyperplasia was similar to that in mice in E2 group(25%vs 16.7%).HFD induced significant changes in mRNA and cicrRNA transcription profiles in the mouse endometria of after 13 and 26 weeks of intervention.The results of GO and KEGG analysis showed that the differentially expressed mRNA induced by high fat diet was mainly concentrated in the immune response,cell cycle,Wnt signaling pathway and metabolic process.The ceRNA network of circRNA-miRNA-mRNA was successfully constructed by bioinformatics analysis.Conclusion:High-fat diet induced significant changes in endometrial RNA transcripts,which may alter endometrial homeostasis.The role of ceRNA network of related cicrRNAs in endometrial lesions induced by high fat diet is worthy of further study.