Multi-omics analysis and experimental verification reveal testicular fatty acid metabolism disorder in non-obstructive azoospermia

Increasing evidence implicates disruptions in testicular fatty acid metabolism as a contributing factor in non-obstructive azoospermia (NOA), a severe form of male infertility. However, the precise mechanisms linking fatty acid metabolism to NOA pathogenesis have not yet been fully elucidated. Multi-omics analyses, including microarray analysis, single-cell RNA sequencing (scRNA-seq), and metabolomics, were utilized to investigate disruptions in fatty acid metabolism associated with NOA using data from public databases. Results identified ACSL6, ACSBG2, and OLAH as key genes linked to fatty acid metabolism dysregulation, suggesting their potential causative roles in NOA. A marked reduction in omega-3 polyunsaturated fatty acids, especially docosahexaenoic acid (DHA), was observed, potentially contributing to the pathological process of NOA. Sertoli cells in NOA patients exhibited apparent fatty acid metabolic dysfunction, with PPARG identified as a key transcription factor (TF) regulating this process. Functional analyses demonstrated that PPARG is crucial for maintaining blood-testis barrier (BTB) integrity and promoting spermatogenesis via regulation of fatty acid metabolism. These findings reveal the pivotal role of fatty acid metabolism in NOA and identify PPARG as a potential therapeutic target.