PPARA and polycystic ovary syndrome: Moreover, deep sequencing of mRNA and lncRNA profiles in a letrozole-induced PCOS rat model showed that the differentially expressed mRNAs were associated with biological adhesion, reproduction, and metabolic processes, and they were also enriched in several specific signaling pathways, including insulin resistance, steroid hormone biosynthesis, PPAR signaling pathway, cell adhesion molecules, autoimmune thyroid disease, and AMPK signaling pathway (39).