Cyclophosphamide Exposure Causes Long-Term Detrimental Effect of Oocytes Developmental Competence Through Affecting the Epigenetic Modification and Maternal Factors' Transcription During Oocyte Growth

Intravenous administration of mitochondria improves ovarian function by anti-apoptosis in the premature ovarian insufficiency model

OBJECTIVE

For patients with contraindications to hormone therapy, the absence of effective treatments for ovarian dysfunction post chemotherapy represents a critical issue requiring resolution. Local administration of mitochondria may enhance ovarian function in premature ovarian insufficiency (POI) by ameliorating diminished mitochondrial activity. Nevertheless, there is a paucity of literature on the efficacy of mitochondrial transplantation through intravenous injection, a less invasive and more convenient method than local injection, for the improvement of ovarian function in POI following chemotherapy.

METHOD

Mitochondria were isolated from mouse livers, their activity and integrity were validated with MitoTracker Red and their localization was examined via confocal microscopy, real-time quantitative PCR and enzyme-linked immunosorbent assay post tail vein injection. An ovarian insufficiency animal model induced by chemotherapy was developed, and ovarian function was assessed through ovarian diameter, vaginal smear, body weight, sex hormone levels and histological analysis. The impact of mitochondrial transplantation on an ovarian cell model was examined through the assessment of mitochondrial function, apoptosis and levels of reactive oxygen species.

CONCLUSION

Tail vein injection of isolated mitochondria has the potential to enhance ovarian functions in an animal model of POI induced by cyclophosphamide, increase mitochondrial activity in impaired ovarian cells and decrease the rate of apoptosis.

High-dose estrogen impairs demethylation of H3K27me3 by decreasing Kdm6b expression during ovarian hyperstimulation in mice

Given that ovarian stimulation is vital for assisted reproductive technology (ART) and results in elevated serum estrogen levels, exploring the impact of elevated estrogen exposure on oocytes and embryos is necessary. We investigated the effects of various ovarian stimulation treatments on oocyte and embryo morphology and gene expression using a mouse model and estrogen-treated mouse embryonic stem cells (mESCs). Female C57BL/6J mice were subjected to two types of conventional ovarian stimulation and ovarian hyperstimulation; mice treated with only normal saline served as controls. Hyperstimulation resulted in high serum estrogen levels, enlarged ovaries, an increased number of aberrant oocytes, and decreased embryo formation. The messenger RNA (mRNA)‍-sequencing of oocytes revealed the dysregulated expression of lysine-specific demethylase 6b (Kdm6b), which may be a key factor indicating hyperstimulation-induced aberrant oocytes and embryos. In vitro, Kdm6b expression was downregulated in mESCs treated with high-dose estrogen; treatment with an estrogen receptor antagonist could reverse this downregulated expression level. Furthermore, treatment with high-dose estrogen resulted in the upregulated expression of histone H3 lysine 27 trimethylation (H3K27me3) and phosphorylated H2A histone family member X (γ-H2AX). Notably, knockdown of Kdm6b and high estrogen levels hindered the formation of embryoid bodies, with a concomitant increase in the expression of H3K27me3 and γ-H2AX. Collectively, our findings revealed that hyperstimulation-induced high-dose estrogen could impair the demethylation of H3K27me3 by reducing Kdm6b expression. Accordingly, Kdm6b could be a promising marker for clinically predicting ART outcomes in patients with ovarian hyperstimulation syndrome.

Intrinsic differences in mTOR activity mediates lineage-specific responses to cyclophosphamide in mouse and human granulosa cells

BACKGROUND

Cyclophosphamide (CTX) often induces oocyte and granulosa cell injury, leading to fertility loss in young female cancer survivors. Deciphering the mechanisms underlying follicular cell injury could offer novel insights into fertility preservation. Granulosa cells represent the most abundant cell type within the follicles and can be generally categorized as cumulus granulosa cells (CGCs) and mural granulosa cells (MGCs). Despite the essential roles of granulosa cells in supporting ovarian function in physiological conditions, their distinct lineage-specific responses to CTX remains elusive.

RESULTS

Here, we performed a genome-wide transcriptome analysis of murine mural and cumulus granulosa cells before and after CTX administration. Compared with MGCs, CGCs exhibited higher basal mammalian target of rapamycin (mTOR) activity and an increased DNA damage response post-injury. Pharmacological mTOR suppression or RNA interference-mediated gene silencing of Raptor, a key component of the mTORC1 complex, significantly reduced DNA damage in granulosa cells induced by 4-HC, an activated form of CTX. Notably, by examining human granulosa cells in response to 4-HC, our results uncovered a conserved role of mTOR inhibition in ovarian protection.

CONCLUSIONS

Taken together, our findings reveal that intrinsic variations in mTOR activity in CGC and MGC lineages determine their differential responses to CTX. Targeting this signaling pathway may prove beneficial in mitigating CTX-induced granulosa cell apoptosis and protecting against ovarian injury.

Protective effects of herbal compounds against cyclophosphamide-induced organ toxicity: a pathway-centered approach

Cyclophosphamide is a key component of numerous chemotherapeutic protocols, demonstrating broad-spectrum efficacy against various malignancies and non-cancerous conditions. This review examines CPM's metabolic pathways, therapeutic applications, and its resulting organ-specific toxicities. Despite its clinical benefits in treating nephrotic syndrome, encephalomyelitis, breast cancer, ovarian cancer, and other diseases, CPM is associated with significant adverse effects on the kidneys, liver, heart, lungs, and intestines. The discussion delves into the molecular mechanisms underlying these toxicities, highlighting dysregulation in key signaling pathways, including Nrf2, NF-κB, MAPK/ERK, and AKT. In addressing these challenges, recent studies have identified various herbal drugs and phytochemicals capable of mitigating CPM-induced toxicity. Notable compounds such as cinnamaldehyde, baicalin, quercetin, and curcumin have demonstrated protective effects. Integrating these herbal formulations with CPM therapy is proposed to enhance patient safety and treatment efficacy. This review underscores the influence of CPM on apoptosis and inflammation pathways, which lead to alterations in organ-specific biomarkers. Phytochemicals may exert protective effects by restoring disrupted signaling pathways and normalizing altered biomarkers. The compilation of phytochemicals presented in this review serves as a valuable resource for researchers exploring other herbal products with potential protective effects against CPM toxicity. A significant gap in the current literature is the lack of clinical trials evaluating phytochemicals that mitigate CPM toxicity in vivo. Rigorous clinical studies are necessary to establish the efficacy and safety of herbal formulations in cancer treatment. Such research will clarify the role of natural remedies in complementing conventional therapies, ultimately improving patient outcomes.

Comparison of large single and small multiple doses of cyclophosphamide exposure in mice during early prepubertal age on fertility outcome

Cyclophosphamide (CY) exposure is known to affect the ovary and impair fertility. Clinically, treatment is generally given over multiple doses, but research models have generally used single doses. The relative effects of administering multiple small doses of CY in the prepubertal period are not elucidated. Two-week-old early-prepubertal Swiss albino female mice were administered with either large single (200 mg/Kg x 1; CY200X1) or small multiple (75 mg/Kg x 4; CY75X4) CY doses, thus a 50% higher total dose. Surviving females were assessed for estrous cyclicity, ovarian follicle reserve, oocyte functional competence, and postnatal assessment of first-generation (F1) pups. Exposure to CY75X4 reduced the loss of ovarian follicles (p < 0.05), and body weight (p < 0.001), and resulted in a larger population of cycling females (p < 0.01) with higher oocyte yield (p < 0.05) compared to CY200X1. Although CY200X1 exposed cycling females had comparable oocyte quality, and fertility index, the postnatal mortality was higher in F1 pups (p < 0.05) in comparison to the CY75X4 group. Although both strategies affect oocyte quality and functional competence similarly, CY75X4, despite the higher overall dose, results in reduced follicle loss, produces higher oocyte/blastocyst yield, and exhibits lower postnatal mortality rates, suggesting a potential advantage over CY200X1 for later fertility and offspring health. The differences in effects of the two treatment models show the need for designing animal model studies that more closely mimic the clinical administration of gonadotoxic therapies such as cyclophosphamide.

Female fertility preservation for family planning: a position statement of the Italian Society of Fertility and Sterility and Reproductive Medicine (SIFES-MR)

PURPOSE

This position statement by the Italian Society of Fertility and Sterility and Reproductive Medicine (SIFES-MR) aims to establish an optimal framework for fertility preservation outside the standard before oncological therapies. Key topics include the role of fertility units in comprehensive fertility assessment, factors impacting ovarian potential, available preservation methods, and appropriate criteria for offering such interventions.

METHODS

The SIFES-MR writing group comprises Italian reproductive physicians, embryologists, and scientists. The consensus emerged after a six-month period of meetings, including extensive literature review, dialogue among authors and input from society members. Final approval was granted by the SIFES-MR governing council.

RESULTS

Fertility counselling transitions from urgent to long-term care, emphasizing family planning. Age, along with ovarian reserve markers, is the primary predictor of female fertility. Various factors, including gynecological conditions, autoimmune disorders, and prior gonadotoxic therapies, may impact ovarian reserve. Oocyte cryopreservation should be the preferred method. Women 30-34 years old and 35-39 years old, without known pathologies impacting the ovarian reserve, should cryopreserve at least 12-13 and 15-20 oocytes to achieve the same chance of a spontaneous live birth they would have if they tried to conceive at the age of cryopreservation (63% and 52%, respectively in the two age groups).

CONCLUSIONS

Optimal fertility counselling necessitates a long-term approach, that nurtures an understanding of fertility, facilitates timely evaluation of factors that may affect fertility, and explores fertility preservation choices at opportune intervals.

The effect of L-carnitine in reactive oxygen species reduction and apoptotic gene expression in mice after cyclophosphamide: An experimental study

Background

Cyclophosphamide (CP), a utilized anticancer drug, is known to cause infertility in women. However, L-carnitine (LC), an antioxidant, has been shown to offer protective benefits against infertility.

Objective

This study aimed to evaluate the levels of reactive oxygen species (ROS) and apoptotic gene expression in mice treated with CP and LC.

Materials and Methods

24 NMRI female mice (6-8 wk, 30 ± 5 gr) were divided into 4 groups: control group: received normal saline intraperitoneal (IP) injection for 10 days; CP group: received 75 mg/kg of CP as a single IP on the 10  th day of the experiment; LC group: received 200 mg/kg of LC IP for 10 days; LC+CP group: received LC for 10 days and CP single IP injection on the 10  th day of the experiment. After 10 days, mice were superovulated. The oviducts were then removed, and the oocytes of each group were collected for evaluating apoptotic gene expression B-cell lymphoma 2(Bcl2), Bcl2-associated X(Bax), and Caspase3 via real-time polymerase chain reaction and intracellular ROS levels by dichloro-dihydro-fluorescein diacetate fluorescence staining.

Results

Data revealed that LC in the LC+CP group significantly increased Bcl2 gene expression (p = 0.01), and decreased Bax and Caspase3 gene expression compared to the CP group (p = 0.03, p = 0.04). LC decreased the ROS level in the LC+CP group compared to the CP group (p < 0.001).

Conclusion

Findings suggest that LC can scavenge the ROS caused by CP and modulate the apoptotic pathway via downregulating the Bax and Caspase3 genes and upregulating the Bcl2 gene in oocytes of mice exposed to CP.

Gynotoxic Effects of Chemotherapy and Potential Protective Mechanisms

Chemotherapy is one of the leading cancer treatments. Unfortunately, its use can contribute to several side effects, including gynotoxic effects in women. Ovarian reserve suppression and estrogen deficiency result in reduced quality of life for cancer patients and are frequently the cause of infertility and early menopause. Classic alkylating cytostatics are among the most toxic chemotherapeutics in this regard. They cause DNA damage in ovarian follicles and the cells they contain, and they can also induce oxidative stress or affect numerous signaling pathways. In vitro tests, animal models, and a few studies among women have investigated the effects of various agents on the protection of the ovarian reserve during classic chemotherapy. In this review article, we focused on the possible beneficial effects of selected hormones (anti-Müllerian hormone, ghrelin, luteinizing hormone, melatonin), agents affecting the activity of apoptotic pathways and modulating gene expression (C1P, S1P, microRNA), and several natural (quercetin, rapamycin, resveratrol) and synthetic compounds (bortezomib, dexrazoxane, goserelin, gonadoliberin analogs, imatinib, metformin, tamoxifen) in preventing gynotoxic effects induced by commonly used cytostatics. The presented line of research appears to provide a promising strategy for protecting and/or improving the ovarian reserve in the studied group of cancer patients. However, well-designed clinical trials are needed to unequivocally assess the effects of these agents on improving hormonal function and fertility in women treated with ovotoxic anticancer drugs.

Insight on cytotoxic NHC gold(I) halide complexes evaluated in multifaceted culture systems

Gold complexes can be a useful system in the fight against cancer. Although many studies have been carried out on in vitro 2D cell culture models embryotoxic assays are particularly lacking. Embryotoxicity and DNA damage are critical concerns in drug development. In this study, the effects of a new N-Heterocyclic carbene (NHC)-Au compound (Bromo[1,3-di-4-methoxybenzyl-4,5-bis(4-methoxyphenyl)imidazol-2-ylidene]gold(I)) at different concentrations were explored using multifaceted approach, encompassing 2D cancer cell cultures, in vivo zebrafish and in vitro bovine models, and compared with a consolidated similar complex (Bromo[1,3-diethyl-4,5-bis(4-methoxyphenyl)imidazol-2-ylidene]gold(I)). The results obtained from 2D cancer cell cultures revealed concentration-dependent effects of the gold compounds by estimating the cytotoxicity with MTT assay and cellular damage as indicated by LDH release. Selected concentrations of gold complexes demonstrated no adverse effects on zebrafish embryo development. However, in bovine embryos, these same concentrations led to significant impairments in the early developmental stages, triggering cell apoptosis and reducing blastocyst competence. These findings underscore the importance of evaluating drug effects across different model systems to comprehensively assess their safety and potential impact on embryonic development.

Rapamycin prevents cyclophosphamide-induced ovarian follicular loss and potentially inhibits tumour proliferation in a breast cancer xenograft mouse model

STUDY QUESTION

To what extent and via what mechanism does the concomitant administration of rapamycin (a follicle activation pathway inhibitor and antitumour agent) and cyclophosphamide (a highly toxic ovarian anticancer agent) prevent cyclophosphamide-induced ovarian reserve loss and inhibit tumour proliferation in a breast cancer xenograft mouse model?

SUMMARY ANSWER

Daily concomitant administration of rapamycin and a cyclic regimen of cyclophosphamide, which has sufficient antitumour effects as a single agent, suppressed cyclophosphamide-induced primordial follicle loss by inhibiting primordial follicle activation in a breast cancer xenograft mouse model, suggesting the potential of an additive inhibitory effect against tumour proliferation.

WHAT IS KNOWN ALREADY

Cyclophosphamide stimulates primordial follicles by activating the mammalian target of the rapamycin (mTOR) pathway, resulting in the accumulation of primary follicles, most of which undergo apoptosis. Rapamycin, an mTOR inhibitor, regulates primordial follicle activation and exhibits potential inhibitory effects against breast cancer cell proliferation.

STUDY DESIGN, SIZE, DURATION

To assess ovarian follicular apoptosis, 3 weeks after administering breast cancer cells, 8-week-old mice were randomized into three treatment groups: control, cyclophosphamide, and cyclophosphamide + rapamycin (Cy + Rap) (n = 5 or 6 mice/group). Mice were treated with rapamycin or vehicle control for 1 week, followed by a single dose of cyclophosphamide or vehicle control. Subsequently, the ovaries were resected 24 h after cyclophosphamide administration (short-term treatment groups). To evaluate follicle abundance and the mTOR pathway in ovaries, as well as the antitumour effects and impact on the mTOR pathway in tumours, 8-week-old xenograft breast cancer transplanted mice were randomized into three treatment groups: vehicle control, Cy, and Cy + Rap (n = 6 or 7 mice/group). Rapamycin (5 mg/kg) or the vehicle was administered daily for 29 days. Cyclophosphamide (120 mg/kg) or the vehicle was administered thrice weekly (long-term treatment groups). The tumour diameter was measured weekly. Seven days after the last cyclophosphamide treatment, the ovaries were harvested, fixed, and sectioned (for follicle counting) or frozen (for further analysis). Similarly, the tumours were resected and fixed or frozen.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) was performed to examine ovarian follicular apoptosis in the short-term treatment groups. All subsequent experiments were conducted in the long-term treatment groups. Tumour growth was evaluated using the tumour volume index. The tumour volume index indicates the relative volume, compared to the volume 3 weeks after tumour cell injection (at treatment initiation) set to 100%. Tumour cell proliferation was evaluated by Ki-67 immunostaining. Activation of the mTOR pathway in tumours was assessed using the protein extracts from tumours and analysed by western blotting. Haematoxylin and eosin staining of ovaries was used to perform differential follicle counts for primordial, primary, secondary, antral, and atretic follicles. Activation of the mTOR pathway in ovaries was assessed using protein extracts from whole ovaries and analysed by western blotting. Localization of mTOR pathway activation within ovaries was assessed by performing anti-phospho-S6 kinase (downstream of mTOR pathway) immunohistochemistry.

MAIN RESULTS AND THE ROLE OF CHANCE

Ovaries of the short-term treatment groups were resected 24 h after cyclophosphamide administration and subjected to TUNEL staining of apoptotic cells. No TUNEL-positive primordial follicles were detected in the control, Cy, and Cy + Rap groups. Conversely, many granulosa cells of growing follicles were TUNEL positive in the Cy group but negative in the control and Cy + Rap groups. All subsequent experimental results were obtained from the long-term treatment groups. The tumour volume index stabilized at a mean of 160-200% in the Cy group and 130% in the Cy + Rap group throughout the treatment period. In contrast, tumours in the vehicle control group grew continuously with a mean tumour volume index of 600%, significantly greater than that of the two treatment groups. Based on the western blot analysis of tumours, the mTOR pathway was activated in the vehicle control group and downregulated in the Cy + Rap group when compared with the control and Cy groups. Ki-67 immunostaining of tumours showed significant inhibition of cell proliferation in the Cy + Rap group when compared with that in the control and Cy groups. The ovarian follicle count revealed that the Cy group had significantly fewer primordial follicles (P < 0.001) than the control group, whereas the Cy + Rap group had significantly higher number of primordial follicles (P < 0.001, 2.5 times) than the Cy group. The ratio of primary to primordial follicles was twice as high in the Cy group than in the control group; however, no significant difference was observed between the control group and the Cy + Rap group. Western blot analysis of ovaries revealed that the mTOR pathway was activated by cyclophosphamide and inhibited by rapamycin. The phospho-S6 kinase (pS6K)-positive primordial follicle rate was 2.7 times higher in the Cy group than in the control group. However, this effect was suppressed to a level similar to the control group in the Cy + Rap group.

LARGE SCALE DATA

None.

LIMITATIONS, REASONS FOR CAUTION

The combinatorial treatment of breast cancer tumours with rapamycin and cyclophosphamide elicited inhibitory effects on cell proliferative potential compared to cyclophosphamide monotherapy. However, no statistically significant additive effect was observed on tumour volume. Thus, the beneficial antitumour effect afforded by rapamycin administration on breast cancer could not be definitively proven. Although rapamycin has ovarian-protective effects, it does not fully counteract the ovarian toxicity of cyclophosphamide. Nevertheless, rapamycin is advantageous as an ovarian protective agent as it can be used in combination with other ovarian protective agents, such as hormonal therapy. Hence, in combination with other agents, mTOR inhibitors may be sufficiently ovario-protective against high-dose and cyclic cyclophosphamide regimens.

WIDER IMPLICATIONS OF THE FINDINGS

Compared with a cyclic cyclophosphamide regimen that replicates human clinical practice under breast cancer-bearing conditions, the combination with rapamycin mitigates the ovarian follicle loss of cyclophosphamide without interfering with the anticipated antitumour effects. Hence, rapamycin may represent a new non-invasive treatment option for cyclophosphamide-induced ovarian dysfunction in breast cancer patients.

STUDY FUNDING/COMPETING INTEREST(S)

This work was not financially supported. The authors declare that they have no conflict of interest.

Unveiling the mechanisms and challenges of cancer drug resistance

Cancer treatment faces many hurdles and resistance is one among them. Anti-cancer treatment strategies are evolving due to innate and acquired resistance capacity, governed by genetic, epigenetic, proteomic, metabolic, or microenvironmental cues that ultimately enable selected cancer cells to survive and progress under unfavorable conditions. Although the mechanism of drug resistance is being widely studied to generate new target-based drugs with better potency than existing ones. However, due to the broader flexibility in acquired drug resistance, advanced therapeutic options with better efficacy need to be explored. Combination therapy is an alternative with a better success rate though the risk of amplified side effects is commonplace. Moreover, recent groundbreaking precision immune therapy is one of the ways to overcome drug resistance and has revolutionized anticancer therapy to a greater extent with the only limitation of being individual-specific and needs further attention. This review will focus on the challenges and strategies opted by cancer cells to withstand the current therapies at the molecular level and also highlights the emerging therapeutic options -like immunological, and stem cell-based options that may prove to have better potential to challenge the existing problem of therapy resistance. Video Abstract.

Investigation of crocin's protective effect on cyclophosphamide-induced hypothalamic-pituitary-gonadal axis defects in adult female rats

Cyclophosphamide is a drug used in chemotherapy. However, it has side effects, including changes in reproductive system functioning. Some herbal compounds can reduce the harmful effects of cyclophosphamide. This study aims to investigate the protective role of crocin against changes caused by Cyclophosphamide in ovarian tissue through changes in the expression of genes involved in the hypothalamic-pituitary-gonadal axis. This experimental study was performed on 24 adult female Wistar rats. Mice were divided into four groups (normal saline, 30 mg/kg cyclophosphamide, 100 mg/kg crocin and 30 mg/kg cyclophosphamide, and 200 mg/kg crocin and 30 mg/kg cyclophosphamide). At the end of the treatment period, the hypothalamus and ovaries were also removed to evaluate ob-Rb, ob-Ra, and NPY genes expression using real-time PCR and histological changes in the ovaries. Data were analyzed by SPSS statistical software. The expression of genes, number of follicles, and follicle diameter significantly decreased in the cyclophosphamide-treated groups compared with the control group. In the crocin and cyclophosphamide-treated groups, drug-induced reproductive complications were mitigated. The current findings indicate that by increasing the expression of genes ob-Rb, ob-Ra, and NPY, crocin could modulate the harmful effects of cyclophosphamide.

The EZH2-H3K27me3 axis modulates aberrant transcription and apoptosis in cyclophosphamide-induced ovarian granulosa cell injury

Chemotherapy-induced ovarian damage and infertility are significant concerns for women of childbearing age with cancer; however, the underlying mechanisms are still not fully understood. Our study has revealed a close association between epigenetic regulation and cyclophosphamide (CTX)-induced ovarian damage. Specifically, CTX and its active metabolite 4-hydroperoxy cyclophosphamide (4-HC) were found to increase the apoptosis of granulosa cells (GCs) by reducing EZH2 and H3K27me3 levels, both in vivo and in vitro. Furthermore, RNA-seq and CUT&Tag analyses revealed that the loss of H3K27me3 peaks on promoters led to the overactivation of genes associated with transcriptional regulation and apoptosis, indicating that stable H3K27me3 status could help to provide a safeguard against CTX-induced ovarian damage. Administration of the H3K27me3-demethylase inhibitor, GSK-J4, prior to CTX treatment could partially mitigate GC apoptosis by reversing the reduction of H3K27me3 and the aberrant upregulation of specific genes involved in transcriptional regulation and apoptosis. GSK-J4 could thus potentially be a protective agent for female fertility when undergoing chemotherapy. The results provide new insights into the mechanisms for chemotherapy injury and future clinical interventions for fertility preservation.

Effects of Ganoderma lucidum polysaccharide peptide ameliorating cyclophosphamide-induced immune dysfunctions based on metabolomics analysis

Ganoderma lucidum polysaccharide peptide (GLPP) is one of the most abundant constituents of Ganoderma lucidum (G. lucidum), with a wide range of functional activities. The present study investigated the immunomodulatory effects of GLPP in cyclophosphamide (CTX)-induced immunosuppressive mice. The results showed that 100 mg/kg/day of GLPP administration significantly alleviated CTX-induced immune damage by improving immune organ indexes, earlap swelling rate, the index of carbon phagocytosis and clearance value, secretion of cytokines (TNF-α, IFN-γ, and IL-2), and immunoglobulin A(IgA) in the mice. Furthermore, ultra-performance liquid chromatography with mass/mass spectrometry (UPLC-MS/MS) was conducted to identify the metabolites, followed by biomarker and pathway analysis. The results showed that GLPP treatment alleviated CTX-induced alterations in the fecal metabolome profile, including arachidonic acid (AA), leukotriene D4 (LTD4), indole-3-ethanol, and formyltetrahydrofolate (CF), by reversing citric acid, malic acid, cortisol, and oleic acid. These results support the concept that GLPP exhibits immunomodulatory activity via the folate cycle, methionine cycle, TCA cycle, fatty acid biosynthesis and metabolism, glycerophospholipid metabolism, AA metabolism, and cAMP pathways. In conclusion, the results could be helpful to understand the use of GLPP to clarify the immunomodulatory mechanism and be used as immunostimulants to prevent CTX-induced side effects in the immune system.

The future of fertility preservation for women treated with chemotherapy

Cytotoxic chemotherapies have been a mainstay of cancer treatment, but are associated with numerous systemic adverse effects, including impacts to fertility and endocrine health. Irreversible ovarian damage and follicle depletion are side-effects of chemotherapy that can lead to infertility and premature menopause, both being major concerns of young cancer patients. Notably, many women will proceed with fertility preservation, but unfortunately existing strategies don't entirely solve the problem. Most significantly, oocyte and embryo freezing do not prevent cancer treatment-induced ovarian damage from occurring, which may result in the impairment of long-term hormone production. Unfortunately, loss of endogenous endocrine function is not fully restored by hormone replacement therapy. Additionally, while GnRH agonists are standard care for patients receiving alkylating chemotherapy to lessen the risk of premature menopause, their efficacy is incomplete. The lack of more broadly effective options stems, in part, from our poor understanding of how different treatments damage the ovary. Here, we summarise the impacts of two commonly utilised chemotherapies - cyclophosphamide and cisplatin - on ovarian function and fertility, and discuss the mechanisms underpinning this damage. Additionally, we critically analyse current research avenues in the development of novel fertility preservation strategies, with a focus on fertoprotective agents.

Integrative analysis of transcriptomic and metabolomic profiles reveals abnormal phosphatidylinositol metabolism in follicles from endometriosis‐associated infertility patients

Endometriosis is a common gynecological disorder that causes female infertility. Our recent research found that excessive oxidative stress in ovaries of endometriosis patients induced senescence of cumulus granulosa cells. Here, we analyzed the transcriptomic and metabolomics profiles of follicles in a mouse model of endometriosis and in patients with endometriosis and investigated the potential function of changed metabolites in granulosa cells. RNA-sequencing indicated that both endometriosis lesions and oxidative stress in mice induced abnormalities of reactive oxidative stress, steroid hormone biosynthesis, and lipid metabolism. The mouse model and women with endometriosis showed altered lipid metabolism. Nontargeted metabolite profiling of follicular fluid from endometriosis and male-factor infertility patients by liquid chromatography mass spectrometry identified 55 upregulated and 67 downregulated metabolites. These differential metabolites were mainly involved in steroid hormone biosynthesis and glycerophospholipid metabolism. Phosphatidylinositol (PI 16:0/18:2) was significantly elevated in follicular fluid from endometriosis patients compared with controls (p < 0.05), while lysophosphatidylinositol (LPI 18:2, 20:2, 18:1, 20:3 and 18:3) was reduced (p < 0.05). Upregulated PI and downregulated LPI correlated with oocyte retrieval number and mature oocyte number. LPI inhibited cellular reactive oxidative stress induced by hemin in granulosa cells. Cell proliferation inhibition, senescence, and apoptosis induced by hemin were partially reversed by LPI. Moreover, LPI administration rescued hemin blocking of cumulus-oocyte complex expansion and stimulated expression of ovulation-related genes. Transcriptomic Switching mechanism at 5' end of the RNA transcript sequencing and western blot revealed that LPI effects on granulosa cells were associated with its regulation of MAPK-ERK1/2 signaling, which was suppressed in the presence of hemin. In conclusion, our results revealed the dysregulation of lipid metabolism in endometriotic follicles. LPI may represent a novel agent for in vitro follicular culture that reverses the excessive oxidative stress from endometriotic lesions. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

HucMSC-EVs Facilitate In Vitro Development of Maternally Aged Preantral Follicles and Oocytes

Follicle developmental capacity and oocyte quality decline with advanced maternal age. Extracellular vesicles from human umbilical cord mesenchymal stem cells (HucMSC-EVs) act as a potential therapeutic product in the treatment of age-related ovarian dysfunction. In vitro culture (IVC) of preantral follicles is a useful method for understanding the mechanism of follicle development and is a promising means for improving female fertility. However, whether HucMSC-EVs have beneficial effects on aged follicle development during IVC has not yet been reported. Our research demonstrated that follicular development with single-addition withdrawal of HucMSC-EVs was better than that with continuous treatment with HucMSC-EVs. HucMSC-EVs facilitated the survival and growth of follicles, promoted the proliferation of granulosa cells (GCs), and improved the steroid hormone secretion of GCs during IVC of aged follicles. Both GCs and oocytes could uptake HucMSC-EVs. Moreover, we observed elevated cellular transcription in GCs and oocytes after treatment with HucMSC-EVs. The RNA sequencing (RNA-seq) results further validated that the differentially expressed genes are related to the promotion of GC proliferation, cell communication, and oocyte spindle organization. Additionally, the aged oocytes displayed a higher maturation rate, presented less aberrant spindle morphology, and expressed a higher level of the antioxidant protein Sirtuin 1 (SIRT1) after treatment with HucMSC-EVs. Our findings suggested that HucMSC-EVs can improve the growth and quality of aged follicles and oocytes in vitro through the regulation of gene transcription, which provides evidence for HucMSC-EVs as potential therapeutic reagents to restore female fertility with advanced age.

Mitochondrial stress response gene Clpp deficiency impairs oocyte competence and deteriorate cyclophosphamide-induced ovarian damage in young mice

Chemotherapy is extensively used to treat cancers and is often associated with ovarian damage and leads to premature ovarian insufficiency and infertility, while the role of mitochondria during ovarian damage with chemotherapy remains unknown. This study used a mouse model with oocyte-specific deletion of mitochondrial stress response gene Caseinolytic peptidase P (Clpp) to investigate mitochondrial homeostasis in oocytes from mice receiving a chemotherapeutic drug cyclophosphamide (CTX). We found that oocyte-specific deletion of Clpp reduced fecundity of the mice at advanced age. The deletion led to meiotic defects with elevated abnormal spindle rate and aneuploidy rate with impaired mitochondrial function in the MII oocytes from 8-week-old mice. Upon CTX treatment at 8-week-old, the oocyte competence and folliculogenesis from the oocyte-specific Clpp knockout mice was further deteriorated with dramatic impairment of mitochondrial distribution and function including elevated ROS level, decreased mitochondrial membrane potential, respiratory chain activity and ATP production. Taken together, the results indicate that that ClpP was required for oocyte competence during maturation and early folliculogenesis, and its deficiency deteriorate cyclophosphamide-induced ovarian damage.

Protective Effects of Antioxidants on Cyclophosphamide-Induced Ovarian Toxicity

The most common limitation of anticancer chemotherapy is the injury to normal cells. Cyclophosphamide, which is one of the most widely used alkylating agents, can cause premature ovarian insufficiency and infertility since the ovarian follicles are extremely sensitive to their effects. Although little information is available about the pathogenic mechanism of cyclophosphamide-induced ovarian damage, its toxicity is attributed to oxidative stress, inflammation, and apoptosis. The use of compounds with antioxidant and cytoprotective properties to protect ovarian function from deleterious effects during chemotherapy would be a significant advantage. Thus, this article reviews the mechanism by which cyclophosphamide exerts its toxic effects on the different cellular components of the ovary, and describes 24 cytoprotective compounds used to ameliorate cyclophosphamide-induced ovarian injury and their possible mechanisms of action. Understanding these mechanisms is essential for the development of efficient and targeted pharmacological complementary therapies that could protect and prolong female fertility.

Barriers to Oncofertility Care among Female Adolescent Cancer Patients in Canada

High survival rates in adolescent cancer patients have shifted the medical focus to the long-term outcomes of cancer treatments. Surgery, chemotherapy, and radiation increase the risk of infertility and infertility-related distress in adolescent cancer patients and survivors. The aims of this narrative review were to (1) describe the psychosocial impacts of cancer-related infertility in adolescents, (2) identify multilevel barriers to fertility preservation (FP) conversations and referrals, and (3) conclude with evidence-based clinical solutions for improving the oncofertility support available to Canadian adolescents. The results of this review revealed that FP decisions occur within the patient, parent, and health care provider (HCP) triad, and are influenced by factors such as parent attitudes, patient maturity, and HCP knowledge. Decision tools and HCP education can promote the occurrence of developmentally appropriate fertility discussions. At the systems level, cost and resource barriers prevent patients from receiving sufficient fertility information and referrals. Clinical models of care (MOCs) can define interdisciplinary roles and referral pathways to improve the integration of oncofertility services into adolescent cancer care. The continued integration of oncofertility care will ensure that all Canadian adolescents receive the exemplary medical and psychological support necessary to make empowered decisions about their own fertility.

Follicle Rescue From Prepubertal Ovaries After Recent Treatment With Cyclophosphamide-An Experimental Culture System Using Mice to Achieve Mature Oocytes for Fertility Preservation

Ovarian tissue cryopreservation is the only feasible method for fertility preservation in prepubertal girls that will undergo gonadotoxic chemotherapy. To date, the only clinical use of cryopreserved tissue is by a later tissue retransplantation to the patient. Clinical challenges in fertility preservation of very young patients with cancer include time constraints that do not allow to retrieve the tissue for cryopreservation before starting chemotherapy and the preclusion of future ovarian tissue transplantation due to the risk of reintroduction of malignant cells in patients with systemic diseases. To overcome these two challenges, we investigated using an experimental model the feasibility of retrieving secondary follicles from ovaries of prepubertal mice after cyclophosphamide (CPA) treatment in increasing doses of 50, 75, and 100 mg/kg. The follicles were thereafter cultured and matured in vitro. The main outcomes included the efficiency of the method in terms of obtained matured oocytes and the safety of these potentially fertility preservative procedures in terms of analyses of oocyte competence regarding normality of the spindle and chromosome configurations. Our findings demonstrated that it was feasible to isolate and culture secondary follicles and to obtain mature oocytes from prepubertal mice ovaries recently treated with CPA. The efficiency of this method was highly demonstrated in the 100 mg/kg CPA group, with near 90% follicle survival rate after 12 days' culture, similarly to control. Around 80% of the follicles met the criteria to put into maturation, and more than 40% of them achieved metaphase II, with normal spindle and chromosome configurations observed. Suboptimal results were obtained in the 50 and 75 mg/kg CPA groups. These paradoxical findings towards CPA dose might probably reflect a more difficult selection of damaged growing follicles from ovaries recently treated with lower doses of CPA and a hampered ability to identify and discard those with reduced viability for the culture.