Assessment role of total phenols and flavonoids extracted from Pleurotus columbinus mushroom on the premature ovarian failure induced by chemotherapy in rats

Background Many species of mushroom contain an assortment of free radical scavengers (Phenolics and Flavonoids compounds) that have made them nutritionally beneficial and a source of expansion of drug production. In this study, we examined the preventive and remedial role of total phenol extract from Pleurotus columbines (TP) in alleviating the consequences of cyclophosphamide (CTX) on the ovaries of female rats. Rats were randomly assigned to four groups: healthy controls, cyclophosphamide (CTX), received a TP (100 mg/kg) orally daily for 14 days and curative group: CTX-TP, we determined and identified a total phenol from a mushroom extract and examined it as an antioxidant agent. To investigate the therapeutic influence, it was administrated 2 weeks after CTX. To assess the impact of TP on ovarian damage caused by CTX, ovarian hormone tests were performed such as luteinizing hormone (LH), 17-β-estradiol (E2), and anti-mullerian hormone (AMH). Besides, follicle-stimulating hormone (FSH) in serum was evaluated, and histopathological analysis of the ovary was examined. Results This study indicates that treatment with TP decreased the severity of cyclophosphamide-induced ovary injury by reducing inflammation and apoptotic effects and increasing the activity of antioxidants. Conclusions TP could be used to alleviate cyclophosphamide-induced ovary injury.

Genomic Consideration in Chemotherapy-Induced Ovarian Damage and Fertility Preservation

Chemotherapy-induced ovarian damage and fertility preservation in young patients with cancer are emerging disciplines. The mechanism of treatment-related gonadal damage provides important information for targeting prevention methods. The genomic aspects of ovarian damage after chemotherapy are not fully understood. Several studies have demonstrated that gene alterations related to follicular apoptosis or accelerated follicle activation are related to ovarian insufficiency and susceptibility to ovarian damage following chemotherapy. This may accelerate follicular apoptosis and follicle reservoir utilization and damage the ovarian stroma via multiple molecular reactions after chemotherapy. This review highlights the importance of genomic considerations in chemotherapy-induced ovarian damage and multidisciplinary oncofertility strategies for providing high-quality care to young female cancer patients.

In Situ Gene Therapy Rescues Doxorubicin-induced Ovarian Damage via Adenovirus Mediated Sirt1 and Tgfbr2

Chemotherapy-induced ovarian damage and fertility loss have negative impacts on the quality of life for female cancer patients worldwide. Thus, we aimed to explore the feasibility and safety of gene therapy for prevention of such damage. First, we validated doxorubicin-induced ovarian damage in human and mouse ovarian tissues and identified two key genes (Sirt1 and Tgfbr2). Next, we generated AdV-Sirt1 and AdV-Tgfbr2 after vectors screening (AdV,AAV and LV) for their ability to transduce mouse ovaries. Finally, we conducted in situ ovarian injection of AdV-Sirt1 and AdV-Tgfbr2 in doxorubicin-treated mice and assessed their ovarian functions and reserves. The interventions dramatically alleviated doxorubicin-induced ovarian damage without apparently influencing the health status of their offspring. Together, our results indicate that AdV-Sirt1 and AdV-Tgfbr2 can serve as effective and safe agents for reducing doxorubicin-induced ovarian damage and also suggest that they may be potentially applicable for post-chemotherapy protection in female cancer patients.

Molecular Mechanism and Prevention Strategy of Chemotherapy- and Radiotherapy-Induced Ovarian Damage

Fertility preservation is an emerging discipline, which is of substantial clinical value in the care of young patients with cancer. Chemotherapy and radiation may induce ovarian damage in prepubertal girls and young women. Although many studies have explored the mechanisms implicated in ovarian toxicity during cancer treatment, its molecular pathophysiology is not fully understood. Chemotherapy may accelerate follicular apoptosis and follicle reservoir utilization and damage the ovarian stroma via multiple molecular reactions. Oxidative stress and the radiosensitivity of oocytes are the main causes of gonadal damage after radiation treatment. Fertility preservation options can be differentiated by patient age, desire for conception, treatment regimen, socioeconomic status, and treatment duration. This review will help highlight the importance of multidisciplinary oncofertility strategies for providing high-quality care to young female cancer patients.

P–434 Effect of let–7a mimic as a new pharmaco-protective agent against chemotherapy-induced ovarian damage on subsequent follicular development and oocyte quality using mouse ovarian transplantation model

Study question What is the long-term impact of let–7a-mimic transfection on oocytes development in new-born mice ovaries exposed to chemotherapy in vitro following transplantation in the kidney? Summary answer The let–7a-mimic restoration protects against chemotherapy-induced ovarian apoptosis and preserves subsequent follicular developmental and acquisition of oocyte maturation competence in mouse. What is known already It is well known that cyclophosphamide and its active metabolites (4-hydroperoxycyclophosphamide, 4-HC) cause irreversible ovarian damage and impair future fertility of cancer survivors. Besides the available fertility preservation options, microRNAs/miRNAs appear to be very attractive and novel targets to prevent theses damage. We showed that miRNAs were dysregulated after exposure to 4-HC in postnatal-day–3 (PND3) ovaries, let–7a being the most downregulated among them. By replacing let–7a function, let–7a-mimic was able to protect mouse follicles against 4-HC in vitro. This previous study suggested that it could preserve the reproductive potential after treatment. However, the impact on subsequent oocytes development is unknown Study design, size, duration PND3 ovaries from C57blxCBAF1 hybrid mice were cultured under 3 conditions: control, chemotherapy for 24h (4-HC/20μΜ/24h), chemotherapy for 24h+let–7a-mimic (4-HC/20μΜ/24h+let–7a-mimic). Nine PND3 ovaries were cultured in the different conditions and then transplanted under the kidney’s capsule of C57blxCBAF1 hybrid adult mice for follicular growth/apoptosis evaluation. Then, 21 ovaries (≥7/condition) were used for oocyte maturation assessment after transplantation and ovarian stimulation. All transplanted mice were observed during 21 days before PND3 ovaries collection. Participants/materials, setting, methods: PND3 ovaries were cultured in vitro using inserts under different conditions. A liposome-based system was used to deliver let–7a-mimic into ovaries and QPCR-assays validated its expression levels after transfection. Apoptosis was evaluated by TUNEL Assay while haematoxylin/eosin staining was used for assessing the follicular morphology, stage and count. The oocyte maturation rate was evaluated at day 21 post-transplantation after gonadotropins injection, mechanical eggs collection and in vitro maturation for 24 hours. Main results and the role of chance The apoptosis assessment confirmed that let–7a-mimic transfection reduced the chemotherapy-induced damage in PND3 ovaries in vitro. The number of primordial follicles was significantly reduced (p < 0.05) compared to control after chemotherapy exposure. However, it was increased in chemo24h+let–7a-mimic compared to chemo24h alone while remaining lower than control (p > 0.05). Accordingly, the number of the transitory follicles reflecting follicular activation was significantly higher in chemo24h compared to control (p < 0.05) and chemo24h+let–7a-mimic but for the last one, the result was not significant. Consequently, chemotherapy induces follicle activation while let–7a restoration tends to slow down this effect. To evaluate the long-term effects of chemotherapy and let–7a-mimic transfection, in vitro exposed PND3 ovaries were transplanted under kidney’s capsule in female adult mice. After 21 days, the ovarian reserve was higher in control, but we observed a slight increase of follicular density in the chemo24+let–7a-mimic compared to chemo24h. Similarly, the percentage of damaged/apoptotic cells was higher in all chemotherapy exposed groups compared to control but the impact was lower after let–7a restoration (12,0% and 28,2% in chemo24+let–7a-mimic and chemo24h, respectively). Importantly, the oocyte maturation rate after transplantation was higher in chemo24h+let–7a-mimic compared to chemo24h (40% versus 18%, respectively), suggesting a preservation of oocytes maturation competence. Limitations, reasons for caution The multiple in vitro/in vivo steps may introduce study bias. Moreover, the oocyte competence and live offspring is currently evaluated. The blastocyst formation and embryo development from oocytes fertilized in vitro, are more relevant parameters for oocyte quality assessment. The birth of healthy animals will confirm let–7a-mimic-transfection safety. Wider implications of the findings: Our previous study demonstrated the anti-apoptotic effect of let–7a restoration in mouse ovaries against chemotherapy. In the current study, we demonstrated a long-term beneficial effect of let–7a restoration strategy on follicular development and oocytes maturation capacity. The results open new perspectives in fertility preservation using pharmacological approach. Trial registration number Not applicable

Onco-fertility and personalized testing for potential for loss of ovarian reserve in patients undergoing chemotherapy: proposed next steps for development of genetic testing to predict changes in ovarian reserve

Women of reproductive age undergoing chemotherapy face the risk of irreversible ovarian insufficiency. Current methods of ovarian reserve testing do not accurately predict future reproductive potential for patients undergoing chemotherapy. Genetic markers that more accurately predict the reproductive potential of each patient undergoing chemotherapy would be critical tools that would be useful for evidence-based fertility preservation counselling. To assess the possible approaches to take to develop personalized genetic testing for these patients, we review current literature regarding mechanisms of ovarian damage due to chemotherapy and genetic variants associated with both the damage mechanisms and primary ovarian insufficiency. The medical literature point to a number of genetic variants associated with mechanisms of ovarian damage and primary ovarian insufficiency. Those variants that appear at a higher frequency, with known pathways, may be considered as potential genetic markers for predictive ovarian reserve testing. We propose developing personalized testing of the potential for loss of ovarian function for patients with cancer, prior to chemotherapy treatment. There are advantages of using genetic markers complementary to the current ovarian reserve markers of AMH, antral follicle count and day 3 FSH as predictors of preservation of fertility after chemotherapy. Genetic markers will help identify upstream pathways leading to high risk of ovarian failure not detected by present clinical markers. Their predictive value is mechanism-based and will encourage research towards understanding the multiple pathways contributing to ovarian failure after chemotherapy.