Key mitochondria-related genes and molecular mechanisms shared between polycystic ovary syndrome and atherosclerosis: A bioinformatics and machine learning study

Polycystic ovary syndrome (PCOS) and atherosclerosis (AS) are interrelated, with studies emphasizing the crucial role of mitochondrial dysfunction in the pathogenesis of both diseases. Therefore, this study utilized bioinformatics analysis to identify key mitochondria-related genes (MitoRGs) and shared mechanisms underlying PCOS and AS. PCOS, AS, and MitoRGs data were obtained from the Gene Expression Omnibus and MitoCarta3.0 databases. The "SVA" and "Limma" packages in R were used to eliminate batch effects and identify differentially expressed genes (DEGs) in PCOS and AS. Shared MitoRGs were identified by intersecting the DEGs between PCOS and AS with mitochondria-related DEGs (MitoDEGs). Least absolute shrinkage and selection operator regression was applied to identify key MitoRGs, which were validated using 2 independent Gene Expression Omnibus datasets to assess their expression levels and diagnostic value. Furthermore, the cell-type identification by estimating relative subsets of RNA transcripts algorithm was used to analyze the correlation between key MitoRGs and immune cells. Our study identified 2306 DEGs in PCOS, 7830 in AS, and 1136 MitoRGs. At the intersection, 66 shared MitoDEGs were identified. These shared MitoDEGs were primarily involved in pathways, such as carbohydrate metabolism and cellular processes. Least absolute shrinkage and selection operator regression and external validation highlighted glutathione S-transferase kappa 1 (GSTK1) as the key MitoRG shared between PCOS and AS. Immune infiltration analysis indicated that GSTK1 was associated with the immune microenvironment in both PCOS and AS. The mitochondrial gene GSTK1 may be a potential biomarker and therapeutic target for PCOS and AS comorbidity. This study provides insights into their shared pathogenesis and early diagnosis.