LINC00092 derived from follicular fluid alleviated the symptoms of PCOS through inactivation of phosphatase and tensin homolog by recruiting KDM5A

Mounting literatures suggest that follicular fluid-derived exosomes (FF-Evs) influence the progression of progression of polycystic ovary syndrome (PCOS). The present study was designed to dissect the underlying mechanisms by which FF-Evs affect the PCOS. A rat model of PCOS was established using Letrozole induction. After treatment with FF-Evs, rats were examined for alterations in hormones, blood glucose, and lipid levels in serum, oestrus cycle, pathology in the ovaries, and apoptosis of ovarian cells. The functional rescue assays were performed to analyze the impact of long non-coding RNA 00092 (LINC00092) on PCOS rats. The cis-regulatory elements involved in the regulation of phosphatase and tensin homolog (PTEN) expression were analyzed using bioinformatic analysis, followed by verification of the mechanism. FF-Evs treatment ameliorated Letrozole-induced enhancement of weight, insulin resistance, dyslipidemia, and LH/FSH ratio, reduction of luteal cells, granulosa cells, and healthy follicles, prolonged oestrus, oestrous cycle arrest, ovarian tissue fibrosis, and ovarian cell apoptosis in rats, which were counteracted by treatment with shRNA targeting LINC00092. Regarding the mechanism, FF-Evs augmented LINC00092 expression in rats. LINC00092 bound to lysine demethylase 5 A (KDM5A), and KDM5A facilitated the demethylation of H3K4me3 to restrain the transcriptional activity of PTEN. Taken together, FF-Evs delivered LINC00092 repressed the transcriptional activity of PTEN by binding to KDM5A to enhance demethylation of H3K4me3, thereby reducing apoptosis in ovarian cells and alleviating PCOS symptoms.