Comprehensive analysis of the effect of MAOA gene on inflammatory bowel disease

Abstract Mounting evidence indicates that a variety of functional genes can significantly affect the progression of inflammatory bowel disease (IBD); nevertheless, the association between monoamine oxidase A (MAOA) and the clinical features of IBD remains unclear. Here we demonstrated that MAOA was negatively correlated with the progression of IBD through GEO datasets and single-cell RNA-Seq online database. This may be that epithelial MAOA plays a major role. Then verified that MAOA was involved in the changes of drug and energy metabolism signaling pathway (MAOA high expression) and inflammatory signaling pathways (MAOA low expression) through Gene Set Enrichment Analysis (GSEA). Most importantly, we predicted the possible transcription factor of MAOA, KLF transcription factor 5 (KLF5). Subsequently, using STRING database, ten interacting proteins [e.g., dopa decarboxylase (DDC), dopamine beta-hydroxylase (DBH), and aldehyde dehydrogenase 2 family member (ALDH2)] of MAOA were found. Notably, ALDH2 is core enrichment in GSEA signaling pathway of MAOA high expression. We have also demonstrated that the MAOA’s expression is associated with therapeutic outcomes in gastrointestinal cancer. Furthermore, our findings indicate that MAOA expression is consistently downregulated in various cancers. Our research establishes the protective role of MAOA in IBD, suggesting its potential as a crucial target for addressing diseases associated with intestinal inflammation.