Supplementary Material for: Spatial transcriptomics of aging rat ovaries reveals unexplored cell subpopulations with reduced antioxidative defence

Introduction: Ovarian aging is characterized by a gradual decline in quantity and quality of oocytes, and lower chance of fertility. Better understanding the genetic modulation during ovarian aging can further address available treatment options for aging-related ovarian diseases and fertility preservation. Methods: A novel technique spatial transcriptomics (ST) was used to investigate the spatial transcriptome features of rat ovaries. Transcriptomes from ST spots in the young and aged ovaries were clustered using differentially expressed genes. These data were analyzed to determine the spatial organization of age-induced heterogeneity and potential mechanisms underlying ovarian aging. Results: In this study, ST technology was applied to profile the comprehensive spatial imaging in young and aged rat ovary. Fifteen ovarian cell clusters with distinct gene-expression signatures were identified. The gene expression dynamics of granulosa cell clusters revealed three sub-types with sequential developmental stages. Aged ovary showed a significant decrease in the number of granulosa cells from antral follicle. Besides, a remarkable rearrangement of interstitial gland cells was detected in aging ovary. Further analysis of aging-associated transcriptional changes revealed that the disturbance of oxidative pathway was a crucial factor in ovarian aging. Conclusions: This study firstly described an aging-related spatial transcriptome changes in ovary, and identified the potential targets for prevention of ovarian aging. These data may provide the basis for further investigations of the diagnosis and treatment of aging-related ovarian disorders.