Identification and verification of biomarkers associated with arachidonic acid metabolism in non-alcoholic fatty liver disease

Elevated arachidonic acid metabolism (AAM) has been linked to the progression of non-alcoholic fatty liver disease (NAFLD). However, the specific role of AAM-related genes (AAMRGs) in NAFLD remains poorly understood. To investigate the involvement of AAMRGs in NAFLD, this study analyzed datasets GSE89632 and GSE135251 from the Gene Expression Omnibus (GEO) and Molecular Signatures Database (MSigDB). Differential expression analysis revealed 2256 differentially expressed genes (DEGs) between NAFLD and control liver tissues. Cross-referencing these DEGs with AAMRGs identified nine differentially expressed AAMRGs (DE-AAMRGs). Least absolute shrinkage and selection operator (LASSO) and univariate logistic regression analyses pinpointed five biomarkers-CYP2U1, GGT1, PLA2G1B, GPX2, and PTGS1-demonstrating significant diagnostic potential for NAFLD, as validated by receiver operating characteristic (ROC) analysis. These biomarkers were implicated in pathways related to AAM and arachidonate transport. An upstream regulatory network, involving transcription factors (TFs) and MicroRNAs (miRNAs), was constructed to explore the regulatory mechanisms of these biomarkers. In vivo validation using a NAFLD mouse model revealed liver histopathological changes, and quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot (WB) analyses confirmed the upregulation of biomarker expression, particularly PTGS1, in NAFLD. The bioinformatic analysis identified five AAM-related biomarkers, enhancing the understanding of NAFLD pathogenesis and offering potential diagnostic targets.