Suppression of p66Shc prevents hyperandrogenism-induced ovarian oxidative stress and fibrosis

Abstract

Background: Rats with hyperandrogen-induced polycystic ovary syndrome (PCOS) have been shown to develop ovarian oxidative stress (OS) and fibrosis. The Sirt1 agonist, resveratrol, can reduce OS through inhibiting p66Shc in other models of OS. Methods: We created a rat PCOS model with increased OS levels following treatment with one of the two androgens, dehydroepiandrosterone (DHEA) and dihydrotestosterone (DHT). The PCOS related features were determined by measurement of malondialdehyde (MDA) and superoxide dismutase (SOD) levels or by examining the reactive oxygen species (ROS) levels using the DCF-DA probe. The potential mechanisms by which p66Shc/Sirt1 mediates ovarian fibrosis were explored by western blotting, quantitative reverse transcription-PCR, immunofluorescence staining, and immunohistochemistry. Results: Hyperandrogen dramatically augmented OS and activation of fibrotic factors in the ovary. Our data demonstrated that treatment with resveratrol enhanced Sirt1 and decreased ovarian OS as well as inhibited phosphorylation of p66Shc both in vivo and in vitro. The treatment suppressed fibrotic factor activation and improved ovarian morphology. Lentivirus-or siRNA-mediated p66Shc knockdown resulted in a dramatic enhancement of Sirt1 expression, down-regulation of ROS and suppression of fibrotic factors in granulosa cells. Moreover, p66Shc overexpression markedly increased the expression of fibrotic factors. Additionally, silencing Sirt1 induced a dramatic increase in p66Shc and enhanced activation of fibrotic factors. Conclusions: p66Shc may be a direct target of Sirt1 for inducing ROS and thus promoting fibrosis. Further exploration of the mechanisms of p66Shc in both fibrosis and OS may provide novel therapeutic strategies that will facilitate the improvement in PCOS symptoms and reproductive functions.

Curcumin in Combination with Aerobic Exercise Improves Follicular Dysfunction via Inhibition of the Hyperandrogen‐Induced IRE1α/XBP1 Endoplasmic Reticulum Stress Pathway in PCOS‐Like Rats

“…Female rats (23 days old) were intraperitoneally injected with pregnant mare serum gonadotropin (20 IU), and 48 h after injection, rats were killed by cervical dislocation. Isolation and primary culture methods of GCs were previously described [ 5 , 6 ]. The primary GC suspensions were cultured in DMEM-F12 medium supplemented with 10% fetal bovine serum (Gibco, Grand Island, USA) and 1% penicillin–streptomycin (Gibco) at 37°C (95% relative humidity, 5% CO 2 ).…”

“…Most studies report that hyperandrogenism is the main cause of infertility owing to PCOS. Our previous research showed that hyperandrogen dramatically augments oxidative stress (OS) and fibrotic factor activation in the ovary [ 5 ] and stimulates chronic low-grade inflammation in the ovary to activate the NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome, further inducing ovarian granulosa cell (GC) pyroptotic death, follicular dysfunction, and ovarian interstitial cell fibrosis [ 6 ]. GCs may undergo excessive OS, chronic low-grade inflammation, and increased apoptosis [ 7 – 9 ].…”

NRF2-Related Epigenetic Modifications in Cardiac and Vascular Complications of Diabetes Mellitus

“…Many antioxidant compounds have been proposed to regulate nfe2l2 expression by modulating DNA methylation at the CpG sites of the promoter sequence of nfe2l2. Resveratrol, widely found in grapes, mulberries, peanuts, and red wine, is a natural phenolic compound with strong anti-inflammatory, antioxidant, and anti-cancer properties (65)(66)(67)(68). Resveratrol was shown to prevent HG-induced oxidative stress in HepG2 cells via suppressing methylation of Nfe2l2, which attenuated HGinduced triglyceride accumulation (36).…”

Expression Regulation and Physiological Role of Transcription Factor FOXO3a During Ovarian Follicular Development

“…Park et al (2020) demonstrated that SIRT1 can downregulate ROS and form a complex with FOXO3a in cells, which can improve the ability of FOXO3a to induce cell cycle arrest and promote cell survival. Recent findings have indicated that resveratrol, a plant polyphenolic compound, can enhance SIRT1 and decrease ovarian oxidative stress as well as inhibit phosphorylation of p66Shc, both in vivo and in vitro (Wang et al, 2020). Thus, in terms of follicular development, there undoubtedly exists an interactive relationship between ROS, SIRT1, and FOXO3a.…”