Association of Arachidonic Acid Metabolism Related Genes With Endometrial Immune Microenvironment and Oxidative Stress in Coupes With Recurrent Implantation Failure.

Background: Alterations in lipid metabolism were reported to impact human fertility; however, there is limited evidence on the association of lipid metabolism with embryo implantation as well as the etiology of recurrent implantation failure (RIF), especially regarding arachidonic acid metabolism.

Methods: Experimental verification research (16 RIF patients and 30 control patients) based on GEO database analysis (24 RIF patients and 24 control patients). The methods in bioinformatics included differential gene screening, functional enrichment analysis, protein-protein interaction network, cluster analysis, weighted gene co-expression network analysis, and so forth. RIF patients were recruited for the experimental validation section. The endometrial samples in the mid-luteal phase were collected and subjected to quantitative real-time PCR detection.

Results: Genes related to oxidative stress were differentially expressed and 17 different types of immune cells exhibited diverse infiltration in three RIF subgroups with different arachidonic acid metabolism. HPGDS, ALOX12, and TBXAS1 showed a strong positive correlation with the infiltration of NK cell, on the contrary, GGT6, PLA2G12A, and PTGS2 showed a strong negative correlation. The overall expression of AAMRGs was positively correlated with the infiltration of activated CD8 T cell, macrophage, natural killer cell, and T follicular helper cell.

Conclusions: The cluster of arachidonic acid metabolism-related genes (AAMRGs) was abnormally expressed and positively associated with excessive oxidative stress as well as extensive infiltration of immune cells, including NK cells among RIF patients. Considering the high heterogeneity of the etiology of RIF, our study utilized the expression of AAMRGs as a typing basis to provide a new understanding of endometrial receptivity from the perspective of lipid metabolism and immune regulation in unexplained RIF couples, providing directions for its etiology and future basic research.