Mtor inhibition by INK128 extends functions of the ovary reconstituted from germline stem cells in aging and premature aging mice

The potential of low-intensity pulsed ultrasound to apply the long-term ovary protection from injury induced by 4-vinylcyclohexene diepoxide through inhibiting granulosa cell apoptosis

The potential of low-intensity pulsed ultrasound (LIPUS) in regulating ovarian function has been demonstrated; however, there is a lack of scientific evidence regarding the long-term efficacy of LIPUS in treating ovarian injury and understanding its regulatory mechanisms. In this study, 4-vinylcyclohexene diepoxide (VCD) was used to induce ovarian injury in rats, and LIPUS was applied to target the damaged ovarian tissues. The research aimed to investigate the long-term protective effect of LIPUS against ovum toxicity induced by VCD and elucidate the associated molecular mechanisms. During the experiment, HE staining was employed for observing the morphology and structure of the ovary, while protein sequencing was utilized for identifying and confirming the molecular mechanism through which LIPUS restores the damaged ovarian structure. The long-term effectiveness of LIPUS in protecting against ovarian injury was evaluated through ELISA, estrous cycle monitoring, fertility testing, and behavioral analysis. The results indicated that LIPUS effectively restored the structure of damaged ovaries. Both in vivo and in vitro studies revealed that this protective effect may be attributed to LIPUS inhibiting apoptosis of ovarian granulosa cells (GCs) by regulating Daxx-mediated ASK1/JNK signaling pathway. Subsequent functional tests demonstrated significant improvements in sex hormone secretion and regulation of estrous cycle within 6 cycles following LIPUS treatment. Additionally, there was a notable increase in offspring numbers after mating. Behavioral analysis revealed that LIPUS effectively alleviated menopausal symptoms resulting from ovarian injury including mood fluctuations, cognitive behavior changes, and reduced muscle excitability levels. These findings suggest that beneficial effects of LIPUS may help reduce VCD-induced ovarian damage with long-term efficacy.

Preservation of ovarian function using human pluripotent stem cell-derived mesenchymal progenitor cells

Ovarian reserve diminishes with age, and older women experience a corresponding shift in sex hormone levels. These changes contribute to an age-dependent decrease in fertility and a decline in overall health. Furthermore, while survival rates following cancer treatment have improved for young female patients, a reduction in ovarian function due to the side effects of such treatments can be difficult to avoid. To date, no effective therapy has been recommended to preserve ovarian health in these patients. Mesenchymal progenitor cells (MPCs) are considered a promising option for cell therapy aimed at maintaining fertility and fecundity. Although MPCs derived from human adult tissues are recognized for their various protective effects against ovarian senescence, they are limited in quantity. Consequently, human pluripotent stem cell-derived MPCs (hPSC-MPCs), which exhibit high proliferative capacity and retain genetic stability during growth, have been utilized to delay reproductive aging. This review highlights the impact of hPSC-MPCs on preserving the functionality of damaged ovaries in female mouse models subjected to chemotherapy and natural aging. It also proposes their potential as a valuable cell source for fertility preservation in women with a variety of diseases.

Molecular and genetic insights into human ovarian aging from single-nuclei multi-omics analyses

The ovary is the first organ to age in the human body, affecting both fertility and overall health. However, the biological mechanisms underlying human ovarian aging remain poorly understood. Here we present a comprehensive single-nuclei multi-omics atlas of four young (ages 23-29 years) and four reproductively aged (ages 49-54 years) human ovaries. Our analyses reveal coordinated changes in transcriptomes and chromatin accessibilities across cell types in the ovary during aging, notably mTOR signaling being a prominent ovary-specific aging pathway. Cell-type-specific regulatory networks reveal enhanced activity of the transcription factor CEBPD across cell types in the aged ovary. Integration of our multi-omics data with genetic variants associated with age at natural menopause demonstrates a global impact of functional variants on gene regulatory networks across ovarian cell types. We nominate functional non-coding regulatory variants, their target genes and ovarian cell types and regulatory mechanisms. This atlas provides a valuable resource for understanding the cellular, molecular and genetic basis of human ovarian aging.

Multiple treatments with human embryonic stem cell-derived mesenchymal progenitor cells preserved the fertility and ovarian function of perimenopausal mice undergoing natural aging

OBJECTIVES

Currently, no approved stem cell-based therapies for preserving ovarian function during aging. To solve this problem, we developed a long-term treatment for human embryonic stem cell-derived mesenchymal progenitor cells (hESC-MPCs). We investigated whether the cells retained their ability to resist ovarian aging, which leads to delayed reproductive senescence.

MATERIALS AND METHODS

In a middle-aged female model undergoing natural aging, we analyzed whether hESC-MPCs benefit the long-term maintenance of reproductive fecundity and ovarian reservoirs and how their transplantation regulates ovarian function.

RESULTS

The number of primordial follicles and mice with regular estrous cycles were increased in perimenopausal mice who underwent multiple introductions of hESC-MPCs compared to age-matched controls. The estradiol levels in the hESC-MPCs group were restored to those in the young and adult groups. Embryonic development and live birth rates were higher in the hESC-MPC group than in the control group, suggesting that hESC-MPCs delayed ovarian senescence. In addition to their direct effects on the ovary, multiple-treatments with hESC-MPCs reduced ovarian fibrosis by downregulating inflammation and fibrosis-related genes via the suppression of myeloid-derived suppressor cells (MDSCs) produced in the bone marrow.

CONCLUSIONS

Multiple introductions of hESC-MPCs could be a useful approach to prevent female reproductive senescence and that these cells are promising sources for cell therapy to postpone the ovarian aging and retain fecundity in perimenopausal women.

Proteomic analysis reveals that cigarette smoke exposure diminishes ovarian reserve in mice by disrupting the CREB1-mediated ovarian granulosa cell proliferation-apoptosis balance

Exposure to cigarette smoke (CS) adversely affects ovarian health and it is currently unknown how CS exposure causes ovarian injury. This study compared the differences in proteomics between CS exposure and healthy control groups using liquid chromatography-tandem mass spectrometry quantitative proteomics to further understand the molecular mechanism of ovarian cell injury in mice exposed to CS. Furthermore, western blotting and qPCR were carried out to validate the proteomic analysis outcomes. CREB1 was selected from the differentially expressed proteins, and then the down-regulation of CREB1 and phosphorylated CREB1(Ser133) expressions were confirmed in mice ovarian tissue and human ovarian granulosa cells (KGN cells) after CS exposure. In addition, the expressions of apoptosis-related proteins BCL-2 and BCL-XL were downregulated, and BAX expression was up-regulated. Moreover, the results of cellular immunofluorescence, flow cytometry, and transmission electron microscopy (TEM) showed that cigarette smoke extract (CSE) efficiently stimulated the production of reactive oxygen species, apoptosis, G1 phase arrest, mitochondrial membrane potential decreases, and ultrastructural changes in KGN cells. KG-501 (CREB inhibitor) aggravated CSE-induced mitochondrial dysfunction and apoptosis-proliferation imbalance in KGN cells mediated by down-regulated CREB1/BCL-2 axis. In addition, CREB1 over-expression partially restores mitochondrial dysfunction and apoptosis-proliferation imbalance of KGN cells induced by CSE. The results suggested that CSE diminished ovarian reserve in mice by disrupting the CREB1-mediated ovarian granulosa cell (GCs) proliferation-apoptosis balance and provided possible therapeutic targets for the clinical intervention of premature ovarian failure (POI) caused by CS exposure.

Growth differentiation factor 7 pretreatment enhances the therapeutic capacity of bone marrow-derived mesenchymal stromal cells against cerebral ischemia-reperfusion injury

Bone marrow-derived mesenchymal stem cells (BMSCs) transplantation is a promising therapeutic strategy for cerebral ischemia/reperfusion (I/R) injury; however, the clinical outcome is barely satisfactory and demands further improvement. The present study aimed to investigate whether preconditioning of BMSCs by recombinant human growth differentiation factor 7 (rhGDF7) could enhance its therapeutic capacity against cerebral I/R injury. Mouse BMSCs and primary neurons were co-cultured and exposed to oxygen glucose deprivation/reperfusion (OGD/R) stimulation. To investigate the role of exosomal microRNA-369-3p (miR-369-3p), inhibitors, RNAi and the miR-369-3p antagomir were used. Meanwhile, mice were intravenously injected with rhGDF7-preconditioned BMSCs and then received cerebral I/R surgery. Markers of inflammation, oxidative stress and neural damage were evaluated. To inhibit AMP-activated protein kinase (AMPK), compound C was used in vivo and in vitro. Compared with cell-free transwell or vehicle-preconditioned BMSCs, rhGDF7-preconditioned BMSCs significantly prevented OGD/R-induced inflammation, oxidative stress and neural damage in vitro. Meanwhile, rhGDF7-preconditioned BMSCs could prevent I/R-induced cerebral inflammation and oxidative stress in vivo. Mechanistically, rhGDF7 preconditioning significantly increased exosomal miR-369-3p expression in BMSCs and then transferred exosomal miR-369-3p to primary neurons, where it bound to phosphodiesterase 4 D (Pde4d) 3'-UTR and downregulated PDE4D expression, thereby preventing I/R-induced inflammation, oxidative stress and neural damage through activating AMPK pathway. Our study identify GDF7 pretreatment as a promising adjuvant reagent to improve the therapeutic potency of BMSCs for cerebral I/R injury and ischemic stroke.

Current understanding of the genomic abnormities in premature ovarian failure: chance for early diagnosis and management

Premature ovarian failure (POF) is an insidious cause of female infertility and a devastating condition for women. POF also has a strong familial and heterogeneous genetic background. Management of POF is complicated by the variable etiology and presentation, which are generally characterized by abnormal hormone levels, gene instability and ovarian dysgenesis. To date, abnormal regulation associated with POF has been found in a small number of genes, including autosomal and sex chromosomal genes in folliculogenesis, granulosa cells, and oocytes. Due to the complex genomic contributions, ascertaining the exact causative mechanisms has been challenging in POF, and many pathogenic genomic characteristics have yet to be elucidated. However, emerging research has provided new insights into genomic variation in POF as well as novel etiological factors, pathogenic mechanisms and therapeutic intervention approaches. Meanwhile, scattered studies of transcriptional regulation revealed that ovarian cell function also depends on specific biomarker gene expression, which can influence protein activities, thus causing POF. In this review, we summarized the latest research and issues related to the genomic basis for POF and focused on insights gained from their biological effects and pathogenic mechanisms in POF. The present integrated studies of genomic variants, gene expression and related protein abnormalities were structured to establish the role of etiological genes associated with POF. In addition, we describe the design of some ongoing clinical trials that may suggest safe, feasible and effective approaches to improve the diagnosis and therapy of POF, such as Filgrastim, goserelin, resveratrol, natural plant antitoxin, Kuntai capsule et al. Understanding the candidate genomic characteristics in POF is beneficial for the early diagnosis of POF and provides appropriate methods for prevention and drug treatment. Additional efforts to clarify the POF genetic background are necessary and are beneficial for researchers and clinicians regarding genetic counseling and clinical practice. Taken together, recent genomic explorations have shown great potential to elucidate POF management in women and are stepping from the bench to the bedside.

Lifelong docosahexaenoic acid intervention ameliorates aging in the telomere-DNA-mitochondria axis in telomerase-deficient mice

The health benefits of n-3 polyunsaturated fatty acids (PUFAs) in multiple age-related diseases are associated with telomere length. Telomerase is intimately related to inflammation and oxidative stress, but whether the underlying function of n-3 PUFAs on telomere maintenance is based on telomerase activation or related mechanisms remains unclear. Herein, we utilized late-generation (G4) telomerase-deficient (Terc^-/-) mice to perform a lifelong docosahexaenoic acid (DHA) intervention to determine the potential of DHA in telomere maintenance and health promotion. Unfortunately, DHA failed to prolong mouse longevity in either intrinsic or premature aging. However, intriguingly, lifelong dietary DHA intervention slowed the aging phenotypes and profoundly attenuated telomere attrition in blood leukocytes and multiple tissues, consistent with decreased β-galactosidase activity and other senescence hallmarks with no observed sex differences. Notably, DHA intervention alleviated telomere attrition-induced γ-H2AX accumulation dependent on poly (ADP-ribose) polymerase 1 (PARP1) recruitment, and further regulated mitochondrial dysfunction critically involved in the DNA damage response. Together with the improvement of mitochondria function, the blocked reactive oxygen species (ROS) accumulation and suppression of the nuclear factor-κB (NF-κB)/nucleotide-binding domain-like receptor protein 3 (NLRP3)/caspase-1 pathways partially indicated anti-oxidative and anti-inflammatory effects of DHA. These data revealed a regulatory paradigm involving DHA in the telomere-DNA-mitochondria feedback loop mediated by DNA damage response and inflammation in alleviating senescence, which may hold potential as a translatable intervention in telomere-related diseases during aging.

Ovarian aging: mechanisms and intervention strategies

Ovarian reserve is essential for fertility and influences healthy aging in women. Advanced maternal age correlates with the progressive loss of both the quantity and quality of oocytes. The molecular mechanisms and various contributing factors underlying ovarian aging have been uncovered. In this review, we highlight some of critical factors that impact oocyte quantity and quality during aging. Germ cell and follicle reserve at birth determines reproductive lifespan and timing the menopause in female mammals. Accelerated diminishing ovarian reserve leads to premature ovarian aging or insufficiency. Poor oocyte quality with increasing age could result from chromosomal cohesion deterioration and misaligned chromosomes, telomere shortening, DNA damage and associated genetic mutations, oxidative stress, mitochondrial dysfunction and epigenetic alteration. We also discuss the intervention strategies to delay ovarian aging. Both the efficacy of senotherapies by antioxidants against reproductive aging and mitochondrial therapy are discussed. Functional oocytes and ovarioids could be rejuvenated from pluripotent stem cells or somatic cells. We propose directions for future interventions. As couples increasingly begin delaying parenthood in life worldwide, understanding the molecular mechanisms during female reproductive aging and potential intervention strategies could benefit women in making earlier choices about their reproductive health.