Chemotherapy-induced ovarian damage and protective strategies

Primordial Follicle Survival and Changes in Ovarian Vasculature May Be Independently Regulated During Chemotherapy

Chemotherapeutic agents induce irreversible gonadotoxic side effects, resulting in endocrine dysfunction and infertility in female cancer survivors. In the current study, we investigated strategies to protect ovarian function from chemotherapy-induced toxicity by evaluating the effects of cisplatin, doxorubicin, or cyclophosphamide on ovarian vasculature and primordial follicle survival. This investigation was conducted using adult CD-1, PDs 5-7 CD-1, and oocyte-specific Trp63 conditional knockout (Trp63 cKO) mice that demonstrated primordial follicles survived following chemotherapy. In control ovaries, vasculature typically surrounds primordial and primary follicles, is in the theca layer as secondary follicles develop, and is distributed among stromal cells. Our findings revealed that the expression pattern of CD31/PECAM-1 (platelet endothelial adhesion molecule-1) was significantly altered in ovaries treated with chemotherapeutic agents compared with controls. The data demonstrate that these agents not only caused the loss of ovarian follicles but also damaged the ovarian vasculature. Using Trp63 cKO mice and CK2II, an inhibitor of checkpoint kinase 2, we demonstrated that vascular damage can occur independently of primordial follicle loss, and VEGFA165 was unable to prevent either outcome. This indicates that the mechanisms governing the death of primordial follicles and vascular damage may not directly affect each other. Long-term ex vivo culture and in vivo experiments demonstrated the ability of ovarian vasculature to recover from cisplatin-induced damage. In conclusion, our study suggests that ovarian follicle survival and vascular integrity may be independently regulated as independent processes, governed by distinct signaling pathway or mechanisms.

Investigations on the effects of in vitro exposure of mouse ovaries to withaferin A, a new candidate for chemotherapy

This study aimed to investigate, in vitro, the toxicity of WTA on ovarian follicles. Initially, a cytotoxicity assay was conducted using tumor and non-tumor cell lines to determine the IC. Initially, a cytotoxicity assay was conducted using tumor and non-tumor cell lines to determine the IC50 of the WTA and validate its antitumor activity. Mouse ovaries were cultured in vitro (IVC) for 6 days in the presence of 1 % dimethyl sulfoxide (DMSO), doxorubicin at 0.3 µg/mL (DXR), or WTA at 0.6 µM or 6.0 µM. DXR or WTA were added to the IVC medium once (1DXR, 1WTA0.6, 1WTA6.0) or three times (3DXR, 3WTA0.6, 3WTA6.0). After the IVC, the ovarian stroma, follicular morphology and development, cell proliferation, senescence, DNA damage, and apoptosis were assessed. The degeneration rate in 3DXR and WTA6.0 (1x and 3x) was higher (p < 0.05) compared to the DMSO group. 1DXR and 3WTA0.6 reduced (p < 0.05) the percentage of primordial follicles and increased (p < 0.05) the number of developing follicles compared to the control (CTR) and DMSO groups. An increase (p < 0.05) in lipofuscin granules was observed with DXR and WTA at both concentrations and exposure frequencies compared to the CTR. In the presence of 3WTA0.6, staining for cleaved caspase-3 was more pronounced (p < 0.05). Additionally, 3WTA0.6, 1WTA6.0, and 3DXR increased (p < 0.05) DNA fragmentation in the stroma compared to the CTR and DMSO groups. We conclude that, like chemotherapy agents used for cancer treatment, WTA induces severe cytotoxic effects on ovarian follicles and stroma, especially at high concentrations and exposure frequencies.

Nicotinamide mononucleotide improves the ovarian reserve of POI by inhibiting NLRP3-mediated pyroptosis of ovarian granulosa cells

BACKGROUND

Premature ovarian insufficiency (POI) is a common clinical problem, but there is currently no effective treatment. NLRP3 inflammasome-induced pyroptosis is thought to be a possible mechanism of POI. Nicotinamide mononucleotide (NMN) has a certain anti-inflammatory effect, providing a promising approach for the treatment of POI.

METHODS

Thirty female Sprague Dawley rats were randomly divided into a control group (n = 10) and a POI group (n = 20). Cyclophosphamide (CTX) was administered for 2 weeks to induce POI. Then the POI group was divided into two groups: the CTX-POI group (n = 10), which was given saline; and the CTX-POI + NMN group (n = 10), which was given NMN at a dose of 500 mg/kg/day for 21 consecutive days. At the end of the study, the serum hormone concentrations of each group were determined, and each group was subjected to biochemical, histopathological, and immunohistochemical analyses. In the in vitro experiment, cell pyroptosis was simulated by using lipopolysaccharide (LPS) and nigricin (Nig), and then KGN cells were treated with NMN, MCC950, and AGK2, and the levels of Nicotinamide adenine dinucleotide (NAD+) and inflammatory factors Interleukin-18(IL-18) and Interleukin-1β(IL-1β) in the cell supernatants were detected, and the levels of pyroptosis-related factors in the cells were determined.

RESULTS

In POI rats, NMN treatments can improve blood hormone levels and partially improve the number of follicles, enhance ovarian reserve function and ovarian index.The evidence is that the increase in NAD+ levels and the activation of SIRT2 expression can reduce the expression of NLRP3, Gasdermin D (GSDMD), Caspase-1, IL-18, and IL-1β in the ovary.

CONCLUSION

NMN improves CTX-induced POI by inhibiting NLRP3-mediated pyroptosis, providing a new therapeutic strategy and drug target for clinical POI patients.

Challenges and Opportunities in Breast Cancer Care in Low-Resourced Countries, Jordan as An Example

Jordan is a relatively small country with a rapidly growing population and a challenged economy. Breast cancer is the most diagnosed cancer among women worldwide and also in Jordan. Though the age-standardized rate (ASR) of breast cancer incidence is still lower than that in Western societies, the number of newly diagnosed cases continues to increase, involving younger women, and new cases are usually detected at more advanced stages. Improvements in breast cancer care across the health care continuum, including early detection, prevention, treatment, and survivorship and palliative care, have become very visible, but may not match the magnitude of the problem. More organized, goal-oriented work is urgently needed to downstage the disease and improve awareness of, access to, and participation in early detection programs. The cost of recently introduced anti-cancer therapies poses a great challenge, but the impact of these therapies on treatment outcomes, including overall survival, is becoming very noticeable. Though the concept of a multidisciplinary approach to breast cancer treatment is often used at most health care facilities, its implementation in real practice varies significantly. The availability of breast reconstruction procedures, survivorship programs, germline genetic testing, counselling, and palliative care is improving, but these are not widely practiced. In this manuscript, we review the status of breast cancer in Jordan and highlight some of the existing challenges and opportunities.