Bioinformatics Analysis On The Mechanism Of Tollip Regulating Hepatic Ischemia-Reperfusion Injury

In liver resection,transplantation and other surgical operations,liver injury caused by liver ischemia-reperfusion is the main cause of surgical failure,and there is no good clinical intervention.It is essential to study the molecular mechanism of hepatic ischemia-reperfusion injury and identify the key molecules that regulate this process for the clinical prevention and treatment of hepatic ischemia-reperfusion injury.In the previous study,we identified a high correlation between Tollip molecule and hepatic ischemia-reperfusion injury by combinatory analysis of proteomics data from mouse liver tissues undergoing ischemia-reperfusion sugery and the DisGeNET database.Further studies showed that Tollip knockout mice showed attenuated liver ischemia-reperfusion injury compared to wild type mice,indicating that Tollip may be a potential factor regulating liver ischemia-reperfusion injury.However,the molecular mechanism of its function remains unclear.In this study,we performed RNA-Seq for liver tissues from WT and Tollip knockout mice undergoing liver ischemia-reperfusion operation and the sequencing data were comprehensively analyzed to dissect the molecular mechanism of Tollip regulation in hepatic ischemia-reperfusion injury.Firstly,we performed quality control and mapped all the quantified sequences to the reference genome for quantitative analysis.Results were further subjected to dimensionality reduction to determine the consistency of samples within the same experimental group and the difference of samples between the experiment groups.Next,the transcriptomic profile change was analyzed and the differentially expressed genes were identified based on the quantitative results of expression of all genes.Using the differentially expressed genes in combination with multiple online databases,we carried out enrichment analysis and interacting network prediction.Based on GO,KEGG,and REACTOME database,enrichment analysis showed that the biological processes related to inflammation and apoptosis were significantly inhibited in Tollip knockout mice.And the marker genes were verified by quantitative RT-PCR.Based on the KEGG database,the analysis of the differentially expressed genes revealed that the inflammation-related pathways were significantly enriched.The correlation analysis of the enriched pathways with liver function demonstrated that the MAPK signaling pathway showed the best correlation.The MAPK pathway was suppressed in Tollip knockout mice,which was consistant with the analysis results obtained from data mining of public database and verified by quantitative RT-PCR.These results suggest that Tollip may act by activating the MAPK signaling pathway in hepatic ischemia-reperfusion injury alleviation.This study has revealed the important role of Tollip in hepatic ischemia-reperfusion injury and its underlying mechanism by integral transcriptomics analysis,molecular biology experiments,joint phenotype analysis and online data mining.Tollip may aggravate liver deficiency mainly by activating MAPK pathway in hepatic ischemia-reperfusion injury.Our research also demonstrates that comprehensive application of bioinformatic analysis is powerful to unveil the biological significance behind the biological data and provide instructive ideas for biological experimental research.