Study on the Reparative Effect of PEGylated Growth Hormone on Ovarian Parameters and Mitochondrial Function of Oocytes From Rats With Premature Ovarian Insufficiency

Mechanisms of mitochondrial dysfunction in ovarian aging and potential interventions

Mitochondria plays an essential role in regulating cellular metabolic homeostasis, proliferation/differentiation, and cell death. Mitochondrial dysfunction is implicated in many age-related pathologies. Evidence supports that the dysfunction of mitochondria and the decline of mitochondrial DNA copy number negatively affect ovarian aging. However, the mechanism of ovarian aging is still unclear. Treatment methods, including antioxidant applications, mitochondrial transplantation, emerging biomaterials, and advanced technologies, are being used to improve mitochondrial function and restore oocyte quality. This article reviews key evidence and research updates on mitochondrial damage in the pathogenesis of ovarian aging, emphasizing that mitochondrial damage may accelerate and lead to cellular senescence and ovarian aging, as well as exploring potential methods for using mitochondrial mechanisms to slow down aging and improve oocyte quality.

Growth hormone reduces aneuploidy and improves oocytes quality by JAK2-MAPK3/1 pathway in aged mice

BACKGROUND

The global delay in women's reproductive age has raised concerns about age-related infertility. The decline in oocyte quality is a limiting factor of female fertility, yet there are currently no strategies to preserve oocyte quality in aged women. Here, we investigated the effects of growth hormone (GH) supplementation on aneuploidy of aged oocytes.

METHODS

For the in vivo experiments, the aged mice (8-month-old) were intraperitoneally injected with GH daily for 8 weeks. For the in vitro experiments, germinal vesicle oocytes from aged mice were treated with GH during oocyte maturation. The impacts of GH on ovarian reserve before superovulation was evaluated. Oocytes were retrieved to assess oocyte quality, aneuploidy and developmental potential characteristics. Quantitative proteomics analysis was applied to investigate the potential targets of GH in aged oocytes.

RESULTS

In this study, we demonstrated that GH supplementation in vivo not only alleviated the decline in oocyte number caused by aging, but also improved the quality and developmental potential of aged oocytes. Strikingly, we discovered that GH supplementation reduced aneuploidy in aged oocytes. Mechanically, in addition to improving mitochondrial function, our proteomic analysis indicated that the MAPK3/1 pathway may be involved in the reduction in aneuploidy of aged oocytes, as confirmed both in vivo and in vitro. In addition, JAK2 may also act as a mediator in how GH regulates MAPK3/1.

CONCLUSIONS

In conclusion, our research reveals that GH supplementation protects oocytes against aging-related aneuploidy and enhances the quality of aged oocytes, which has clinical significance for aged women undergoing assisted reproduction technology.

Mechanisms of and Potential Medications for Oxidative Stress in Ovarian Granulosa Cells: A Review

Granulosa cells are essential for follicle initiation and development, and their abnormal function or apoptosis is a crucial factor leading to follicular atresia. A state of oxidative stress occurs when the balance between the production of reactive oxygen species and the regulation of the antioxidant system is disturbed. Oxidative stress is one of the most important causes of the abnormal function and apoptosis of granulosa cells. Oxidative stress in granulosa cells causes female reproductive system diseases, such as polycystic ovary syndrome and premature ovarian failure. In recent years, studies have confirmed that the mechanism of oxidative stress in granulosa cells is closely linked to the PI3K-AKT signaling pathway, MAPK signaling pathway, FOXO axis, Nrf2 pathway, NF-κB signaling pathway, and mitophagy. It has been found that drugs such as sulforaphane, Periplaneta americana peptide, and resveratrol can mitigate the functional damage caused by oxidative stress on granulosa cells. This paper reviews some of the mechanisms involved in oxidative stress in granulosa cells and describes the mechanisms underlying the pharmacological treatment of oxidative stress in granulosa cells.

Comparison of the different animal modeling and therapy methods of premature ovarian failure in animal model

Incidence of premature ovarian failure (POF) is higher with the increase of the pace of life. The etiology of POF is very complex, which is closely related to genes, immune diseases, drugs, surgery, and psychological factors. Ideal animal models and evaluation indexes are essential for drug development and mechanism research. In our review, we firstly summarize the modeling methods of different POF animal models and compare their advantages and disadvantages. Recently, stem cells are widely studied for tumor treatment and tissue repair with low immunogenicity, high homing ability, high ability to divide and self-renew. Hence, we secondly reviewed recently published data on transplantation of stem cells in the POF animal model and analyzed the possible mechanism of their function. With the further insights of immunological and gene therapy, the combination of stem cells with other therapies should be actively explored to promote the treatment of POF in the future. Our article may provide guidance and insight for POF animal model selection and new drug development.

The Clinical Application of Growth Hormone and Its Biological and Molecular Mechanisms in Assisted Reproduction

Growth hormone (GH) has been used as a co-gonadotrophin in assisted reproduction, particularly in poor ovarian responders. The application of GH has been alleged to activate primordial follicles and improve oocyte quality, embryo quality, and steroidogenesis. However, the effects of GH on the live birth rate among women is controversial. Additionally, although the basic biological mechanisms that lead to the above clinical differences have been investigated, they are not yet well understood. The actions of GH are mediated by GH receptors (GHRs) or insulin-like growth factors (IGFs). GH regulates the vital signal transduction pathways that are involved in primordial follicular activation, steroidogenesis, and oocyte maturation. However, the therapeutic windows and duration of GH administration during assisted reproductive technology require further investigation. The review aimed to clarify the role of GH in human fertility from a molecular and biological point of view to provide evidence for proper GH administration.

Identification of Prognosis Biomarkers for High-Grade Serous Ovarian Cancer Based on Stemness

In this paper, high-grade serous ovarian cancer (HGSOC) is studied, which is the most common histological subtype of ovarian cancer. We use a new analytical procedure to combine the bulk RNA-Seq sample for ovarian cancer, mRNA expression-based stemness index (mRNAsi), and single-cell data for ovarian cancer. Through integrating bulk RNA-Seq sample of cancer samples from TCGA, UCSC Xena and single-cell RNA-Seq (scRNA-Seq) data of HGSOC from GEO, and performing a series of computational analyses on them, we identify stemness markers and survival-related markers, explore stem cell populations in ovarian cancer, and provide potential treatment recommendation. As a result, 171 key genes for capturing stem cell characteristics are screened and one vital cancer stem cell subpopulation is identified. Through further analysis of these key genes and cancer stem cell subpopulation, more critical genes can be obtained as LCP2, FCGR3A, COL1A1, COL1A2, MT-CYB, CCT5, and PAPPA, are closely associated with ovarian cancer. So these genes have the potential to be used as prognostic biomarkers for ovarian cancer.

Proteomic and Bioinformatic Analysis of Decellularized Pancreatic Extracellular Matrices

Tissue microenvironments are rich in signaling molecules. However, factors in the tissue matrix that can serve as tissue-specific cues for engineering pancreatic tissues have not been thoroughly identified. In this study, we performed a comprehensive proteomic analysis of porcine decellularized pancreatic extracellular matrix (dpECM). By profiling dpECM collected from subjects of different ages and genders, we showed that the detergent-free decellularization method developed in this study permits the preservation of approximately 62.4% more proteins than a detergent-based method. In addition, we demonstrated that dpECM prepared from young pigs contained approximately 68.5% more extracellular matrix proteins than those prepared from adult pigs. Furthermore, we categorized dpECM proteins by biological process, molecular function, and cellular component through gene ontology analysis. Our study results also suggested that the protein composition of dpECM is significantly different between male and female animals while a KEGG enrichment pathway analysis revealed that dpECM protein profiling varies significantly depending on age. This study provides the proteome of pancreatic decellularized ECM in different animal ages and genders, which will help identify the bioactive molecules that are pivotal in creating tissue-specific cues for engineering tissues in vitro.

Hyperin Alleviates Triptolide-Induced Ovarian Granulosa Cell Injury by Regulating AKT/TSC1/mTORC1 Signaling

Premature ovarian insufficiency (POI) is characterized by the loss of ovarian function before 40 years of age and affects approximately 1% of women worldwide. Caragana sinica is a traditional Miao (a Chinese ethnic minority) medicine that improves ovarian function and follicular development. In the present study, we aimed to investigate the effect of active ingredients of C. sinica on POI and determine underlying mechanisms. Herein, the chemical composition of the C. sinica compound was analyzed using ultra-high-performance liquid chromatography, which identified hyperin (HR) as one of the main ingredients in C. sinica. Then, interaction targets of HR and POI were predicted and analyzed using network pharmacology and bioinformatics. The effect of HR on triptolide (TP)-induced granulosa cell injury was evaluated, and the underlying mechanism was explored based on bioinformatic results. A total of 100 interaction targets for POI and HR were obtained. The protein-protein interaction network of identified interaction targets emphasized the topological importance of AKT1. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that HR might regulate POI by modulating the mechanistic target of rapamycin (mTOR) signaling pathway. In addition, the KEGG graph of the mTOR signaling pathway revealed that AKT phosphorylation inhibits the TSC1/2, while TSC1/2 activation inhibits the expression of mTORC1. The fundamental experiment revealed that HR increased proliferation, progesterone receptor levels, and estradiol levels decreased by TP in KGN cells. Additionally, HR alleviated TP-induced apoptosis and G1/G1 phase arrest in KGN cells. Western blotting demonstrated that HR increased the phosphorylation of AKT and mTORC1 and decreased TSC1 expression in TP-induced KGN cells. Collectively, our findings revealed that HR alleviates TP-induced granulosa cell injury by regulating AKT/TSC1/mTORC1 signaling, providing insight into the treatment of POI.