Expression And Significance Of CircRNA In Intrahepatic Cholestasis During Pregnancy

Research background and purpose:Intrahepatic cholestasis of pregnancy(ICP)is a common complication of pregnancy,and its pathogenesis has not been fully defined.Recent studies have found that its pathogenesis may be related to genetic and environmental factors.One of the most studied genetic factors in recent years is circ RNA.Several studies have shown that circ RNA is a kind of multi-functional molecule with stable structure,widely existing in a variety of eukaryotes and organisms,can participate in a variety of biological processes,has tissue specificity,and can be widely used in the diagnosis,treatment and pathogenesis of a variety of diseases.In this study,circ RNA high-throughput sequencing technology was used to analyze the differential expression of circ RNA in placental tissues of ICP and normal pregnant women control group,and biological information of differentially expressed circ RNA was analyzed to analyze the main target genes of differentially expressed circ RNA and their involvement in biological pathways.To investigate the possible role of circ RNA in ICP.Materials and Methods:1.This study was approved by the Medical Board of the First Affiliated Hospital of Chengdu Medical College(2022CYFYYIRB-BA-Feb22)to obtain placental tissue samples with informed consent.Thirty placental tissues of ICP patients from March2022 to January 2023 were collected from the obstetrics department of the hospital as the experimental group,while the other 30 placental tissues were normal pregnant women,and the selected pregnant women were tested regularly during pregnancy.Three patients in each group were randomly selected for high-throughput sequencing of placenta samples,and clinical information of patients was recorded.2.Three pairs of randomly selected specimens were placed in dry ice and transported to Zhejiang Lianchuan Biotechnology Company in cold chain for circ RNA sequencing.The differential genes were screened with the difference multiple(FC value)greater than 2.0 and p<0.05 after correction as the standard.3.Genomes were analyzed through gene ontology(GO)annotation analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis We can better predict functional changes in circ RNA.4.Circinteractome analysis website was used to select mirnas that could bind to Circrnas,and then Target Scan was used to predict the target gene function of the selected mirnas.5.KEGG and GO enrichment analysis were performed for all related target genes of mi RNA in Circ RNA sponges.6.Construct circ RNA-mi RNA and circ RNA-mi RNA m RNA networks using Cytoscape software,select several target genes with the most mi RNA targeting effect as the research focus,and conduct KEGG and GO enrichment analysis on the selected target genes.And which disease-free genes have been studied before.To explore the possible biological mechanisms through which target genes play their biological functions.Result:1.High-throughput sequencing analysis of circ RNA found that a total of 176 circ RNA were differentially expressed between the ICP group and the control group according to FC value greater than 2.0 times,and P value less than 0.05 as the standard,of which 73 were significantly up-regulated,Down 103.2.Through differential gene GO enrichment analysis and KEGG enrichment analysis,we found that circ RNA plays a role in many biological processes,including protein transport,oxidation-reduction,autophagy and other biological processes.3.GO and KEGG enrichment analysis of all target genes showed that target genes could be involved in signal transduction,cell differentiation,apoptosis,cell population proliferation and other biological processes.It has the molecular functions of protein binding,metal ion binding,DNA binding,ATP binding,proteolysis and so on.4.Select differential genes for mi RNA and m RNA analysis,draw Circ RNA-mi RNA-m RNA network diagram,and search for target genes with the most targeted relationships: Transferring-receptor(TFRC)gene,G protein signal regulator-4gene(RGS4),GIPC3,ALG10 B,CYB561D1,KCNJ6,GMFB.5.Carry out GO and KEGG analysis on the target genes selected in the fourth step:(1)Molecular functions of TFRC involve: protein binding,iron ion transport,transferrin transport and other related items.It can participate in the regulation of gene expression,regulation of cell growth,regulation of cell population proliferation,inflammatory response and other biological processes.(2)The molecular functions of RGS4 mainly include: participating in the regulation of G protein-coupled receptor signaling pathway,positive regulation of GTPase activity,negative regulation of cell growth,iron death,iron absorption and transport and other biological processes.(3)The molecular functions of KCNJ6 mainly include: protein binding,potassium ion migration,etc.Participate in estrogen signaling pathway,oxytocin signaling pathway and other biological processes.Conclusion:1.This study showed that there were significant differences in circ RNA expression in placental tissue between ICP and normal pregnancy control group;2.The Circ RNA-mi RNA-TEFC axis can be used as a promising pathway to study ICP through the analysis of differential gene regulatory networks.The mechanism may be through chemokine and cytokine signaling pathways to regulate cellular iron metabolism,lipid oxidation and other biological processes,and participate in the occurrence and development of ICP.3.Circ RNA may be involved in the growth,migration and apoptosis of placental tissue cells through the Circr Na-mi RNA-RGS4 axis,and may also be involved in the formation of ICP by inducing cholestasis caused by biliary duct epithelial cell injury.4.Circ RNA may be involved in regulating estrogen metabolism through the Circrna-mir Na-KCNJ6 axis,thus causing cholestasis and leading to the biological occurrence of ICP.