Objective: To identify novel transcriptomic changes to eutopic endometrium by exposure to chronic mild hypernadrogenemia (testosterone [T]) with/without exposure to an obesogenic Western-style diet (WSD).
Design: Two-by-two factorial arrangement of treatments.
Setting: National primate research center.
Animals: Rhesus macaque females were chronically exposed to T and/or consumed a WSD from menarche through adulthood. After 4.5 years of treatment, Tru-Cut endometrial biopsies were obtained at the midsecretory phase (n = 6-4/group), and paired-end sequencing of RNA was performed. Several females in the T, WSD, and T+WSD cohorts developed endometriosis within 6 months of biopsy; a separate analysis was performed contrasting diagnosis of endometriosis stage 0-2 versus stages 3 and 4 (American Society for Reproductive Medicine revised criteria).
Interventions: Chronic exposure to mild elevation of T (~five-fold elevation) and/or WSD from menarche until adulthood.
Main outcome measures: Limma voom empirical Bayes pipeline was performed to detect differentially expressed RNAs (DEs) significantly impacted by treatments and endometriosis severity. Differentially expressed RNAs were then interrogated by Ingenuity Pathway Analyses and Protein Analysis through Evolutionary Relationships.
Results: Total DEs included C versus T, 469; C versus WSD, 525; C versus T+WSD, 549; and T versus T+WSD, 1,505. The majority of DEs mapped to the ontology pathways: heterotrimeric G-protein signaling pathways Gi alpha and Gs alpha (C vs. T), WNT signaling (C vs. WSD and T vs. T+WSD), and Huntington disease (C vs. T+WSD). A total of 2,171 DEs from eutopic endometrium were altered by the presence of stage 3 and 4 endometriosis lesions.
Conclusions: The present global transcriptomic analyses demonstrate that the greatest magnitude of changes occurred in contrasts of C and T versus T+WSD, adding to the evidence that these two insults have a synergistic effect on female physiology. These data also support the concept that prior alterations to the function of eutopic endometrium increase the risk for endometriosis.
Keywords: Endometrium; Western-style diet; endometrial transcriptome; endometriosis; hyperandrogenemia.