ObjectiveTo establish a microRNA-mRNA differential expression network for alcoholic hepatitis (AH), and to investigate new targets for the diagnosis and treatment of AH. MethodsDifferentially expressed microRNAs and mRNAs between AH patients and normal controls were screened out. Related software including TargetScan, DIANA, MIRDB, PICTAR, and miRWalk 2.0 was used to search for the target genes of differentially expressed microRNA, and a key microRNA-mRNA network was established using the differentially expressed mRNAs that changed in an opposite way to microRNA. The Database for Annotation, Visualization and Integrated Discovery was used for the gene ontology (GO) and Kyoto Encyclopedia of Genes and Genome (KEGG) analyses of target genes. The GCBI online software (www.gcbi.com.cn) was used for enrichment analysis of target genes and core network establishment. The GeneMANIA database in Cytoscape software (genemania.org) was used to perform a protein-protein interaction analysis of key target genes. The above three methods were compared in terms of the search for key pathways involved in the development of AH. ResultsA key microRNA-mRNA network was established with 5 differentially expressed microRNAs including hsa-mir-21-5p, hsa-mir-148a-3p, and hsa-mir-30e-5p and 51 target genes including collagen type IV alpha 1 chain (COL4A1), thrombospondin-2 (THBS2), and integrin alpha 6 (IGTA6). A protein-protein interaction network of key target genes was established. The GO analysis and various pathway analyses showed that the PI3K-Akt pathway and local adhesion were closely associated with AH. ConclusionDuring the development of AH, there are complex interactions between the related proteins of key target genes. COL4A1 and THBS2 may promote the development of AH by activating ITGA6 to regulate the PI3K-Akt pathway and the process of local adhesion. The establishment of the microRNA-mRNA network reveals the key links in the development of AH and highlights the focus of research. The discovery of the genes associated with the PI3K-Akt pathway in AH is expected to provide new targets for the diagnosis and treatment of AH. [ABSTRACT FROM AUTHOR]