Melatonin prevents cisplatin‐induced primordial follicle loss via suppression of PTEN/AKT/FOXO3a pathway activation in the mouse ovary

Abstract

Premature ovarian failure (POF) is a major side effect of chemotherapy in young cancer patients. To develop pharmaceutical agents for preserving fertility, it is necessary to understand the mechanisms responsible for chemotherapy-induced follicle loss. Here, we show that treatment with cisplatin, a widely used anticancer drug, depleted the dormant follicle pool in mouse ovaries by excessive activation of the primordial follicles, without inducing follicular apoptosis. Moreover, we show that co-treatment with the antioxidant melatonin prevented cisplatin-induced disruption of the follicle reserve. We quantified the various stages of growing follicles, including primordial, primary, secondary, and antral, to demonstrate that cisplatin treatment alone significantly decreased, whereas melatonin co-treatment preserved, the number of primordial follicles in the ovary. Importantly, analysis of the PTEN/AKT/FOXO3a pathway demonstrated that melatonin significantly decreased the cisplatin-mediated inhibitory phosphorylation of PTEN, a key negative regulator of dormant follicle activation. Moreover, melatonin prevented the cisplatin-induced activating phosphorylation of AKT, GSK3β, and FOXO3a, all of which trigger follicle activation. Additionally, we show that melatonin inhibited the cisplatin-induced inhibitory phosphorylation and nuclear export of FOXO3a, which is required in the nucleus to maintain dormancy of the primordial follicles. These findings demonstrate that melatonin attenuates cisplatin-induced follicle loss by preventing the phosphorylation of PTEN/AKT/FOXO3a pathway members; thus, melatonin is a potential therapeutic agent for ovarian protection and fertility preservation during chemotherapy in female cancer patients.

Knockdown of PRKAR2B Results in the Failure of Oocyte Maturation

“…Sectioned samples (5 μm thickness) were applied to slides (Fisher Scientific, USA) and dried overnight. Following deparaffinization with xylene, immunohistochemistry was performed as previously described using rabbit anti-PRKAR2B antibody (1: 100 dilution, Abcam, UK, cat# ab75993) [29]. …”

Melatonin Relieves Busulfan-Induced Spermatogonial Stem Cell Apoptosis of Mouse Testis by Inhibiting Endoplasmic Reticulum Stress

“…Melatonin affects the regulation of testicular development and male reproduction by stimulating the secretion of gonadotropins and testosterone [26]. It also prevents cisplatin-induced primordial follicle loss [27]. In addition, the research recently published by our group has reported that melatonin has beneficial effects on oxidative apoptosis of mouse SSCs induced by busulfan [28].…”

Alleviation of endoplasmic reticulum stress protects against cisplatin-induced ovarian damage

“…Various rescue methods have been tested to restore chemotherapy-induced ovarian damage, including human amniotic epithelial cells [33], co-treatment with a gonadotropin-releasing hormone agonist [34], melatonin treatment [19], and umbilical cord mesenchymal stem cells [35, 36]. However, the effectiveness has not been confirmed in the ovarian function and fertility when these treatments have been applied in clinical practice.…”

“…The experimental group received intraperitoneal injections of CDDP (2.5 mg/kg/d in saline) (Sigma-Aldrich, Shanghai, China) for 7 consecutive days, and the control group were injected with saline. This dosage was according to a previous study [19] and our preliminary results showing that this is the minimum dose causing significant morphological changes within 7 days when compared with the control group. After anesthesia induced with 10% chloral hydrate, the mice were killed and their ovaries rapidly dissected.…”