Premature Ovarian Insufficiency (POI) Induced by Dynamic Intensity Modulated Radiation Therapy via P13K-AKT-FOXO3a in Rat Models

Redox Biomarkers and Matrix Remodeling Molecules in Ovarian Cancer

Ovarian cancer (OC) has emerged as the leading cause of death due to gynecological malignancies among women. Oxidative stress and metalloproteinases (MMPs) have been shown to influence signaling pathways and afflict the progression of carcinogenesis. Therefore, the assessment of matrix-remodeling and oxidative stress intensity can determine the degree of cellular injury and often the severity of redox-mediated chemoresistance. The study group comprised 27 patients with serous OC of which 18% were classified as Federation of Gynecology and Obstetrics (FIGO) stages I/II, while the rest were diagnosed grades III/IV. The control group comprised of 15 ovarian tissue samples. The results were compared with genetic data from The Cancer Genome Atlas. Nitro-oxidative stress, inflammation and apoptosis biomarkers were measured colorimetrically/fluorometrically or via real-time PCR in the primary ovarian tumor and healthy tissue. Stratification of patients according to FIGO stages revealed that high-grade carcinoma exhibited substantial alterations in redox balance, including the accumulation of protein glycoxidation and lipid peroxidation products. TCGA data demonstrated only limited prognostic usefulness of the studied genes. In conclusion, high-grade serous OC is associated with enhanced tissue oxidative/nitrosative stress and macromolecule damage that could not be overridden by the simultaneously augmented measures of antioxidant defense. Therefore, it can be assumed that tumor cells acquire adaptive mechanisms that enable them to withstand the potential toxic effects of elevated reactive oxygen species.

Single-nucleus RNA Sequencing reveals the mechanism of cigarette smoke exposure on diminished ovarian reserve in mice

The systematic toxicological mechanism of cigarette smoke (CS) on ovarian reserve has not been extensively investigated. Female 8-week-old C57BL/6 mice at peak fertility were exposed to CS or indoor air only for 30 days (100 mice per group) and the effects of CS on ovarian reserve were assessed using Single-Nucleus RNA Sequencing (snRNA-seq). In addition, further biochemical experiments, including immunohistochemical staining, ELISA, immunofluorescence staining, transmission electron microscopy, cell counting kit-8 assay, flow cytometry analysis, senescence-associated β-galactosidase staining, and western blotting, were accomplished to confirm the snRNA-seq results. We identified nine main cell types in adult ovaries and the cell-type-specific differentially expressed genes (DEGs) induced by CS exposure. Western blot results verified that down-regulation of antioxidant genes (Gpx1 and Wnt10b) and the steroid biosynthesis gene (Fdx1) occurred in both ovarian tissue and human granulosa cell-like tumor cell line (KGN cells) after CS exposure. Five percent cigarette smoke extract (CSE) effectively stimulated the production of reactive oxygen species (ROS), DNA damage, cellular senescence and markedly inhibited KGN cell proliferation by inducing G1-phase cell cycle arrest. Moreover, down-regulation of Gja1, Lama1 and the Ferroptosis indicator (Gpx4) in granulosa cells plays a significant role in ultrastructural changes in the ovary induced by CS exposure. These observations suggest that CS exposure impaired ovarian follicle reserve might be caused by REDOX imbalance in granulosa cells. The current study systematically determined the damage caused by CS in mouse ovaries and provides a theoretical basis for early clinical prediction, diagnosis and intervention of CS exposure-associated primary ovarian insufficiency (POI), and is of great significance in improving female reproductive health.

The role of oxidative stress in ovarian aging: a review

Ovarian aging refers to the process by which ovarian function declines until eventual failure. The pathogenesis of ovarian aging is complex and diverse; oxidative stress (OS) is considered to be a key factor. This review focuses on the fact that OS status accelerates the ovarian aging process by promoting apoptosis, inflammation, mitochondrial damage, telomere shortening and biomacromolecular damage. Current evidence suggests that aging, smoking, high-sugar diets, pressure, superovulation, chemotherapeutic agents and industrial pollutants can be factors that accelerate ovarian aging by exacerbating OS status. In addition, we review the role of nuclear factor E2-related factor 2 (Nrf2), Sirtuin (Sirt), mitogen-activated protein kinase (MAPK), protein kinase B (AKT), Forkhead box O (FoxO) and Klotho signaling pathways during the process of ovarian aging. We also explore the role of antioxidant therapies such as melatonin, vitamins, stem cell therapies, antioxidant monomers and Traditional Chinese Medicine (TCM), and investigate the roles of these supplements with respect to the reduction of OS and the improvement of ovarian function. This review provides a rationale for antioxidant therapy to improve ovarian aging.