Dysregulated cytokine profile associated with biochemical premature ovarian insufficiency

Advances in cytokine-based herbal medicine against premature ovarian insufficiency: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Premature ovarian insufficiency (POI) refers to a dramatic decrease in the number and/or quality of oocytes in the ovaries before the age of 40 years, and is a key cause of female infertility. The prevalence of POI has been increasing annually and tends to be younger. Researches on the etiology of POI and related pathogenesis are still very limited. Herbal medicine can treat many gynecological diseases. And herbal medicine is effective in reproductive health care such as infertility. In recent years, it has been found that immune modulation by cytokines (CK) can prevent or intervene in POI, and herbal medicine can treat POI by regulating CK to improve ovarian function and fertility.

AIM OF THE STUDY

This review presents an overview of the molecular mechanisms of regulation of POI related CK, and reports the therapeutic effect of herbal medicine on POI including herbal medicine formulas, single herbal medicine, herbal medicine active components and acupuncture. This review provides theoretical support for clinical prevention and treatment of POI, and provides new ideas for researches on herbal medicine treatment of POI.

MATERIALS AND METHODS

We performed a collection of relevant scientific articles from different scientific databases regarding the therapeutic effect of herbal medicine on POI by regulating CK, including PubMed, Web of Science, Wanfang Database, CNKI and other publication resources. The search terms used in this review include, 'premature ovarian insufficiency', 'premature ovarian failure (POF)', 'infertility', 'herbal medicine', 'acupuncture', 'cytokine', 'interleukin (IL)', 'tumor necrosis factor-α (TNF-α)', 'interferon-γ (IFN-γ)', 'transforming growth factor-β (TGF-β)', 'vascular endothelial growth factor (VEGF)', 'immune' and 'inflammation'. This review summarized and analyzed the therapeutic effect of herbal medicine according to the existing experimental and clinical researches.

RESULTS

The results showed that herbal medicine treats POI through CK (including ILs, TNF-α, INF-γ, VEGF, TGF-β and others) and related signaling pathways, which regulates reproductive hormones disorder, reduces ovarian inflammatory damage, oxidative stress, apoptosis and follicular atresia, improves ovarian pathological damage and ovarian reserve function.

CONCLUSIONS

This review enriches the theory of POI treatments based on herbal medicine by regulating CK. The specific mechanisms of action and clinical researches on the treatment of POI by herbal medicine should be strengthened in order to promote the application of herbal medicine in the clinic and provide new ideas and better choices for the treatment of POI.

Analysis of Inflammatory Markers in Response to Induction of Reprometabolic Syndrome by a Eucaloric High Fat Diet in Normal Weight Women

Obesity is associated with chronic low-level inflammation and is known to contribute to metabolic dysfunction and hypogonadotropic hypogonadism, which we have previously termed the 'Reprometabolic Syndrome.' To investigate potential factors involved in obesity-related reproductive endocrine dysfunction, we conducted a secondary analysis of inflammatory markers in a sample of normal weight women exposed to a one-month eucaloric high-fat diet (HFD), which, as reported earlier, induced the relative hypogonadotropic hypogonadism characteristic of Reprometabolic Syndrome. Eighteen healthy women with a BMI between 18.0-24.9 kg/m2 and regular menstrual cycles participated in the study. Frequent blood sampling was performed during the early follicular phase before and after the one-month eucaloric HFD intervention (48% of calories from fat). Serum samples pooled from each participant were analyzed using immunoassay to measure levels of 30 cytokines, interleukins, and chemokines. Differences between pre- and post-HFD intervention measures were examined by one-sample t-tests. Exposure to the eucaloric HFD did not result in changes in body weight. HFD-induction of Reprometabolic Syndrome in normal weight women was associated with a significant elevation only in the anti- inflammatory cytokine IL-10 (p = 0.04). Eotaxin, IL-6 and MIP-1β also increased in response to the HFD, but not statistically significantly (p = 0.07). Results suggest that the increase in multiple inflammatory markers, typically associated with obesity, are not primary mediators of the relative hypogonadotropic hypogonadism of Reprometabolic Syndrome. Clinical Trials Registration Number: NCT02653092; Date of Registration: January 6, 2016.

Comprehensive analysis of lncRNA-miRNA-mRNA ceRNA network and key genes in granulosa cells of patients with biochemical primary ovarian insufficiency

Primary ovarian insufficiency (POI) is a common condition leading to the pathological decline of ovarian function in women of reproductive age, resulting in amenorrhea, hypogonadism, and infertility. Biochemical premature ovarian insufficiency (bPOI) is an intermediate stage in the pathogenesis of POI in which the fertility of patients has been reduced. Previous studies suggest that granulosa cells (GCs) play an essential role in the pathogenesis of POI, but their pathogenetic mechanisms remain unclear. To further explore the potential pathophysiological mechanisms of GCs in POI, we constructed a molecular long non-coding RNA (lncRNA)-microRNA (miRNA)-messenger RNA (mRNA) network using GC expression data collected from biochemical premature ovarian failure (bPOI) patients in the GEO database. We discovered that the GCs of bPOI patients had differential expression of 131 mRNAs, 191 lncRNAs, and 28 miRNAs. By systematic network analysis, we identified six key genes, including SRSF1, PDIA5, NEURL1B, UNK, CELF2, and CFL2, and five hub miRNAs, namely hsa-miR-27a-3p, hsa-miR-24-3p, hsa-miR-22-3p, hsa-miR-129-5p, and hsa-miR-17-5p, and the results suggest that the expression of these key genes may be regulated by two hub miRNAs, hsa-miR-27a-3p and hsa-miR-17-5p. Additionally, a POI model in vitro was created to confirm the expression of a few important genes. In this study, we discovered a unique lncRNA-miRNA-mRNA network based on the ceRNA mechanism in bPOI for the first time, and we screened important associated molecules, providing a partial theoretical foundation to better understand the pathogenesis of POI.

Identification of transcriptome characteristics of granulosa cells and the possible role of UBE2C in the pathogenesis of premature ovarian insufficiency

BACKGROUND

Premature ovarian insufficiency (POI) is an important cause of infertility characterized by the functional decline of the ovary. Granulosa cells (GCs) around oocytes are critical for folliculogenesis, and GC dysfunction is one of the important etiologies of POI. The aim of this study was to explore the potential biomarkers of POI by identifying hub genes and analyze the correlation of biomarkers with immune infiltration in POI using RNA profiling and bioinformatics analysis.

METHODS

RNA sequencing was performed on GCs from biochemical POI (bPOI) patients and controls. Differential expression analysis and weighted gene co-expression network analysis (WGCNA) were used to explore the candidate genes. qRT‒PCR was performed to verify the expression of hub genes. Western blot, Cell Counting Kit-8, 5-ethynyl-2'-deoxyuridine (EdU) assays, TUNEL (TdT-mediated dUTP Nick-End Labeling) and flow cytometry analysis were used to validate the possible role of ubiquitin-conjugating enzyme 2C (UBE2C) in POI. CIBERSORT was adopted to explore immune cell infiltration and the correlation between UBE2C and immune cells in bPOI.

RESULTS

Through analysis of differentially expressed genes (DEGs) and WGCNA, we obtained 143 candidate genes. After construction of the protein‒protein interaction (PPI) network and analysis with Cytoscape, 10 hub genes, including UBE2C, PBK, BUB1, CDC20, NUSAP1, CENPA, CCNB2, TOP2A, AURKB, and FOXM1, were identified and verified by qRT‒PCR. Subsequently, UBE2C was chosen as a possible biomarker of POI because knockdown of UBE2C could inhibit the proliferation and promote the apoptosis of GCs. Immune infiltration analysis indicated that monocytes and M1 macrophages may be associated with the pathogenesis of POI. In addition, UBE2C was negatively correlated with monocytes and M1 macrophages in POI.

CONCLUSIONS

This study identified a hub gene in GCs that might be important in the pathogenesis of POI and revealed the key role of UBE2C in driving POI. Immune infiltration may be highly related with the onset and etiology of POI.

Elevated cell-free mitochondria DNA level of patients with premature ovarian insufficiency

BACKGROUND

Premature ovarian insufficiency (POI) patients present with a chronic inflammatory state. Cell-free mitochondria DNA (cf-mtDNA) has been explored as a reliable biomarker for estimating the inflammation-related disorders, however, the cf-mtDNA levels in POI patients have never been measured. Therefore, in the presenting study, we aimed to evaluate the levels of cf-mtDNA in plasma and follicular fluid (FF) of POI patients and to determine a potential role of cf-mtDNA in predicting the disease progress and pregnancy outcomes.

METHODS

We collected plasma and FF samples from POI patients, biochemical POI (bPOI) patients and control women. Quantitative real-time PCR was used to measure the ratio of mitochondrial genome to nuclear genome of cf-DNAs extracted from the plasma and FF samples.

RESULTS

The plasma cf-mtDNA levels, including COX3, CYB, ND1 and mtDNA79, were significantly higher in overt POI patients than those in bPOI patients or control women. The plasma cf-mtDNA levels were weakly correlated with ovarian reserve, and could not be improved by regular hormone replacement therapy. The levels of cf-mtDNA in FF, rather than those in plasma, exhibited the potential to predict the pregnancy outcomes, although they were comparable among overt POI, bPOI and control groups.

CONCLUSIONS

The increased plasma cf-mtDNA levels in overt POI patients indicated its role in the progress of POI and the FF cf-mtDNA content may hold the value in predicting pregnancy outcomes of POI patients.

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.

Single-cell RNA sequencing of peripheral blood reveals immune cell dysfunction in premature ovarian insufficiency

Background

Premature ovarian insufficiency (POI) is one of the most common causes of female infertility and the etiology is highly heterogeneous. Most cases are idiopathic and the pathogenesis remains unclear. Previous studies proved that the immune system plays a crucial role in POI. However, the precise role of immune system remains unclear. This study aimed to analyze the characteristics of peripheral blood mononuclear cells (PBMC) from patients with POI by single-cell RNA sequencing (scRNA-seq) and to explore the potential involvement of immune response in idiopathic POI.

Methods

PBMC was collected from three normal subjects and three patients with POI. PBMC was subjected to scRNA-seq to identify cell clusters and differently expressed genes (DEGs). Enrichment analysis and cell-cell communication analysis were performed to explore the most active biological function in the immune cells of patients with POI.

Results

In total, 22 cell clusters and 10 cell types were identified in the two groups. Compared with normal subjects, the percentage of classical monocytes and NK cells was decreased, the abundance of plasma B cells was increased, and CD4/CD8 ratio was significantly higher in POI. Furthermore, upregulation of IGKC, IFITM1, CD69, JUND and downregulation of LYZ, GNLY, VCAN, and S100A9 were identified, which were enriched in NK cell-mediated cytotoxicity, antigen processing and presentation, and IL-17 signaling pathway. Among them, IGHM and LYZ were respectively the most significantly upregulated and downregulated genes among all cell clusters of POI. The strength of cell-cell communication differed between the healthy subjects and patients with POI, and multiple signaling pathways were assessed. The TNF pathway was found to be unique in POI with classical monocytes being the major target and source of TNF signaling.

Conclusions

Dysfunction of cellular immunity is related to idiopathic POI. Monocytes, NK cells, and B cells, and their enriched differential genes may play a role in the development of idiopathic POI. These findings provide novel mechanistic insight for understanding the pathogenesis of POI.

The TH 22-mediated IL-22 deficiency associated with premature ovarian insufficiency

RESEARCH QUESTION

Is deficiency of IL-22 associated with premature ovarian insufficiency (POI)?

DESIGN

Levels of IL-22 and IL-22BP, IL-22-producing T cells, and IL22RA1/IL10R2 expression were measured and compared among 29 patients with POI, 42 with precursor stage of POI (pre-POI) and 46 control women. Correlation of serum IL-22 and IL-22⁺ CD4⁺ T subsets with ovarian reserve markers were further analyzed.

RESULTS

IL-22 levels in serum significantly differed among control women and patients with pre-POI and POI, with the lowest concentrations in POI group (p = .019). Significant reduction of peripheral CD4⁺ IL-22⁺ T cells was observed in patients with POI (p = .010), which mainly contributed by decrease of CD4⁺ IL-22⁺ IL-17^- T_H 22 cells (p = .012) but not T_H 17 cells (p = .125). Levels of serum IL-22 and IL-22-producing CD4⁺ T subsets were significantly correlated with ovarian reserve markers, including AMH, bilateral AFC, follicle-stimulating hormone (FSH), and E2 (p < .05). The specific receptor IL22RA1 expression was marginally reduced in granulosa cells from patients with pre-POI (p = .051). No difference of IL-22BP was observed either in serum (p = .216) or follicular fluid (p = .856) among groups.

CONCLUSIONS

Our study first demonstrated the significant association between T_H 22-mediated IL-22 deficiency and ovarian insufficiency, which provide new insights into the autoimmune disturbance and opens new avenues for exogenous IL-22 administration as potential intervention of POI.

A Pilot Study on Biochemical Profile of Follicular Fluid in Breast Cancer Patients

Breast cancer (BC) is the most common type of cancer among women in almost all countries worldwide and is one of the oncological pathologies for which is indicated fertility preservation, a type of procedure used to help keep a person's ability to have children. Follicular fluid (FF) is a major component of oocyte microenvironment, which is involved in oocyte growth, follicular maturation, and in communication between germ and somatic cells; furthermore, it accumulates all metabolites during oocytes growth. To obtain information about changes on fertility due to cancer, we aimed at investigating potential biomarkers to discriminate between FF samples obtained from 16 BC patients and 10 healthy women undergoing in vitro fertilization treatments. An NMR-based metabolomics approach was performed to investigate the FF metabolic profiles; ELISA and western blotting assays were used to investigate protein markers of oxidative and inflammatory stress, which are processes closely related to cancer. Our results seem to suggest that FFs of BC women display some significant metabolic alterations in comparison to healthy controls, and these variations are also related with tumor staging.

Assessment of RANTES, MIP4A, MMP7, MMP9, MMP14, TIMP 1, TIMP 2 and TIMP 3 concentration in the follicular fluid of patients undergoing in vitro fertilization/embryo transfer procedure

Introduction

Matrix metalloproteinases (MMP) degrade extracellular matrix. Some studies show that MMP9 concentration in follicular fluid (FF) may play a role in oocyte maturation and in vitro fertilization (IVF) success. The immunology of follicular fluid is still not fully understood.

Aim

Assessment of RANTES, MIP4A, MMP7, MMP9, MMP14, TIMP 1, TIMP 2 and TIMP 3 concentration in the follicular fluid of patients undergoing in vitro fertilization/embryo transfer procedure.

Material and methods

This case-control study included 20 randomly selected patients with a positive pregnancy (PPG) test and 20 patients with a negative pregnancy (NPG) test after IVF/ET. In FF obtained during oocyte retrieval, the concentrations of MIP4A, MMP7, MMP14, TIMP 1, TIMP 2, TIMP 3, RANTES, IL-12p40, and IL-17A were measured. Their effect on the characteristics of follicles, embryos, and the efficiency of IVF and ET were analysed.

Results

There was no statistically significant relationship between a positive pregnancy test and the results of the immunoassay performed. The number of COC-1 correlates significantly and positively with RANTES (r = 0.34; p = 0.038) and IP-10 (r = 0.329; p = 0.038). MII correlates significantly and positively with RANTES (r = 0.341, p = 0.031). The number of top-quality embryos correlates significantly and positively with IL-17A (r = 0.451, p = 0.004) and TIMP 1 (r = 0.44, p = 0.005).

Conclusions

The concentration of IL-17A and TIMP 1 may predict IVF/ET success. Further studies are required on the influence of the follicular fluid immunological environment on oocyte maturation and quality and, subsequently, embryo development.

A review of autoimmunity and immune profiles in patients with primary ovarian insufficiency

Primary ovarian insufficiency (POI) is a complicated clinical syndrome characterized by progressive deterioration of ovarian function. Autoimmunity is one of the main pathogenic factors affecting approximately 10% to 55% of POI cases. This review mainly focuses on the role of autoimmunity in the pathophysiology of POI and the potential therapies for autoimmunity-related POI. This review concluded that various markers of ovarian reserve, principally anti-Müllerian hormone, could be negatively affected by autoimmune diseases. The presence of lymphocytic oophoritis, anti-ovarian autoantibodies, and concurrent autoimmune diseases, are the main characteristics of autoimmune POI. T lymphocytes play the most important role in the immune pathogenesis of POI, followed by disorders of other immune cells and the imbalance between pro-inflammatory and anti-inflammatory cytokines. A comprehensive understanding of immune characteristics of patients with autoimmune POI and the underlying mechanisms is essential for novel approaches of treatment and intervention for autoimmune POI.

Bone marrow mesenchymal stem cells in premature ovarian failure: Mechanisms and prospects

Premature ovarian failure (POF) is a common female reproductive disorder and characterized by menopause, increased gonadotropin levels and estrogen deficiency before the age of 40 years old. The etiologies and pathogenesis of POF are not fully clear. At present, hormone replacement therapy (HRT) is the main treatment options for POF. It helps to ameliorate perimenopausal symptoms and related health risks, but can't restore ovarian function and fertility fundamentally. With the development of regenerative medicine, bone marrow mesenchymal stem cells (BMSCs) have shown great potential for the recovery of ovarian function and fertility based on the advantages of abundant sources, high capacity for self-renewal and differentiation, low immunogenicity and less ethical considerations. This systematic review aims to summarize the possible therapeutic mechanisms of BMSCs for POF. A detailed search strategy of preclinical studies and clinical trials on BMSCs and POF was performed on PubMed, MEDLINE, Web of Science and Embase database. A total of 21 studies were included in this review. Although the standardization of BMSCs need more explorations, there is no doubt that BMSCs transplantation may represent a prospective therapy for POF. It is hope to provide a theoretical basis for further research and treatment for POF.

Evaluation of expression CXCL8 chemokine and its relationship with oocyte maturation and embryo quality in the intracytoplasmic sperm injection method

BACKGROUND

The present study aimed to evaluate the expression of the chemokine CXCL8 in both mRNA and protein levels in the serum, follicular fluid (FF), and cumulus cells (CCs) and its relationship with oocyte maturation and embryo quality in women undergoing intracytoplasmic sperm injection (ICSI).

METHODS

A total of 87 women who underwent an ICSI cycle were evaluated in two groups, including the case group (female factor infertility) and the control group (fertile). In the serum, FF, and CCs, the protein and mRNA expression of CXCL8 were measured using immunosorbent assay and Real-Time PCR, respectively. The quality and quantity of the oocytes and embryos were assessed, and the relationship of protein and mRNA CXCL8 was evaluated with oocyte maturation and embryo quality.

RESULTS

The level of protein and mRNA of CXCL8 was significantly higher in the serum, FF, and CCs in the case group than in the control group. In the case group, the expression of mRNA and protein of CXCL8 had a significant increase in FF and CCs compared to serum; also, there was a CXCL8 protein significant increase in FF compared to CCs. The count of oocytes obtained, MII oocytes and the percentage of oocyte maturity significantly decreased in the case group. The expression of CXCL8 was inversely related to oocyte maturation, but no relationship was observed with embryo quality.

CONCLUSIONS

The elevated concentrations of CXCL8 in the serum and FF seem to be a predictor as a potential non-invasive biomarker for the oocyte maturation outcome in women with different causes of female factor infertility.

A decade of discovery: the stunning progress of premature ovarian insufficiency research in China

Premature ovarian insufficiency (POI) is one of key aspects of ovarian infertility. Due to early cession of ovarian function, POI imposes great challenges on the physiological and psychological health of women, and becomes a common cause of female infertility. In the worldwide, there has been a special outpouring of concern for about four million reproductive-aged women suffering from POI in China. Driven by advances in new technologies and efforts invested by Chinses researchers, understanding about POI has constantly been progressing over the past decade. Here, we comprehensively summarize and review the landmark development and achievements from POI studies in China spanning 2011 to 2020, which aims to provide key insights from bench to bedside.

Altered T lymphocyte subtypes and cytokine profiles in follicular fluid associated with diminished ovary reserve

PROBLEM

Diminished ovarian reserve (DOR) is a daunting obstacle in in vitro fertilization (IVF) or intra cytoplasmic sperm injection (ICSI), leading to poor reproductive outcomes. We aim to characterize the T cell and cytokine profiles in follicular fluid (FF) and elucidate its contribution to the development of DOR.

METHOD OF STUDY

A total of 92 infertile women were enrolled in the study. We assessed the ultrastructure, proliferation, and apoptosis of granulosa cells (GCs). The levels of CCL5 and cytokines in FF was measured. Additionally, we classified the T cells and analyzed cytokines production in T cell. We further verified whether CCL5 can recruit specific T cell subcytes to the follicles.

RESULTS

Cytoplasmic vacuolization, nucleolar dissociation, partial shortening, swelling, and fusion of mitochondrial cristae were obvious in GCs with DOR. The proliferation of GCs decreased and the proportion of apoptosis increased in DOR. The down-regulation of Bcl-2 and up-regulation of caspase3 were seen in GCs with DOR. The number of CD8⁺ T cells and proportion of CD8⁺ /CD4⁺ T cells in DOR exceeded the control. Higher positive percentage of CD69, CCR5, and IFN-γ in CD8⁺ T cells, lower positive percentage of IL-10 in CD4⁺ T cells and PD-1 in CD8⁺ T cells were detected in DOR. CCL5 accumulated promoting the recruitment of CD8⁺ T cells to the follicles on interaction with CCR5.

CONCLUSION

The abnormal proportion of CD8⁺ T cells and elevated CCL5 and IFN-γ may change the immune balance in FF and impair the growth of GCs, which in turn fuel the progression of DOR.

Induction of Collagen I by CXCL10 in Ovarian Theca-Stroma Cells via the JNK Pathway

Premature ovarian insufficiency (POI) poses a great threat to reproductive-age women. Ovarian fibrogenesis is a basic histologic feature of POI. Ovarian theca-stroma cells are responsible for ovarian fibrosis, but few studies have focused on the ovarian microenvironment. The role and mechanism of chemokines in the development of POI remain unclear. Here, we evaluated C-X-C motif chemokine ligand 10 (CXCL10) in biochemical POI patients, POI patients, and a POI mouse model. CXCL10 levels in serum and follicular fluid were higher in both bPOI and POI patients than in controls. An increased level of CXCL10 was also observed in a POI mouse model. CXCL10 concentrations in serum and follicular fluid were positively associated with follicle-stimulating hormone and negatively associated with antral follicle count. Our study for the first time found that CXCL10 induced COL1A1 and COL1A2 production, two subunits of collagen I in mouse theca-stroma cells by activating the JNK/c-Jun pathway. Inhibition of JNK and c-Jun attenuated the increases of COL1A1 and COL1A2 caused by CXCL10. Moreover, CXCL10 had no effects on hormone synthesis, proliferation, and apoptosis in human luteinized granulosa (hGL) cells. Our findings revealed a potential diagnostic value of CXCL10 in the early stage of POI and shed new insights into the biological function of CXCL10 in ovarian fibrosis.

Function of Follicular Cytokines: Roles Played during Maturation, Development and Implantation of Embryo

A balance within the immune system is necessary for the proper development of ovarian follicles. Numerous cytokines were detected in follicular fluid, the role of which in reproductive physiology seems crucial. They influence the development and maturation of the follicle, ovulation, and corpus luteum formation, as well as embryo implantation and maintenance of pregnancy. The analysis of follicular fluid requires its collection by puncturing of the ovary, which is usually executed in connection with various gynaecological procedures. When interpreting such test results, clinical indications for a given procedure and the method of patient preparation should be taken into account. This review revealed the results of currently available studies on the concentration of pro-inflammatory cytokines in follicular fluid in various forms of infertility. Additionally, it presented cytokines, whose concentration has a significant impact on the size of ovarian follicles, their number, the effectiveness of in vitro fertilisation, development of the embryo, and chances of correct implantation. Despite the many recent publications, the knowledge of follicular fluid immunology in the context of reproductive pathology is superficial and further research is required to extensively understand the roles of individual cytokines in reproductive pathology. In the future, this knowledge may enable patients’ individual qualifications to individual methods of infertility treatment, as well as the possible adjustment of the treatment regimen to the patient’s immune profile.

Advanced Oxidation Protein Products Induce G1/G0-Phase Arrest in Ovarian Granulosa Cells via the ROS-JNK/p38 MAPK-p21 Pathway in Premature Ovarian Insufficiency

The mechanism underlying the role of oxidative stress and advanced oxidation protein products (AOPPs) in the aetiology of premature ovarian insufficiency (POI) is poorly understood. Here, we investigated the plasma AOPP level in POI patients and the effects of AOPPs on granulosa cells both in vitro and in vivo. KGN cells were treated with different AOPP doses, and cell cycle distribution, intracellular reactive oxygen species (ROS), and protein expression levels were measured. Sprague–Dawley (SD) rats were treated daily with PBS, rat serum albumin, AOPP, or AOPP+ N-acetylcysteine (NAC) for 12 weeks to explore the effect of AOPPs on ovarian function. Plasma AOPP concentrations were significantly higher in both POI and biochemical POI patients than in controls and negatively correlated with anti-Müllerian hormone and the antral follicle count. KGN cells treated with AOPP exhibited G1/G0-phase arrest. AOPP induced G1/G0-phase arrest in KGN cells by activating the ROS-c-Jun N-terminal kinase (JNK)/p38 mitogen-activated protein kinase (MAPK)-p21 pathway. Pretreatment with NAC, SP600125, SB203580, and si-p21 blocked AOPP-induced G1/G0-phase arrest. In SD rats, AOPP treatment increased the proportion of atretic follicles, and NAC attenuated the adverse effects of AOPPs in the ovary. In conclusion, we provide mechanistic evidence that AOPPs may induce cell cycle arrest in granulosa cells via the ROS-JNK/p38 MAPK-p21 pathway and thus may be a novel biomarker of POI.

MERTK-Mediated LC3-Associated Phagocytosis (LAP) of Apoptotic Substrates in Blood-Separated Tissues: Retina, Testis, Ovarian Follicles

Timely and efficient elimination of apoptotic substrates, continuously produced during one’s lifespan, is a vital need for all tissues of the body. This task is achieved by cells endowed with phagocytic activity. In blood-separated tissues such as the retina, the testis and the ovaries, the resident cells of epithelial origin as retinal pigmented epithelial cells (RPE), testis Sertoli cells and ovarian granulosa cells (GC) provide phagocytic cleaning of apoptotic cells and cell membranes. Disruption of this process leads to functional ablation as blindness in the retina and compromised fertility in males and females. To ensure the efficient elimination of apoptotic substrates, RPE, Sertoli cells and GC combine various mechanisms allowing maintenance of tissue homeostasis and avoiding acute inflammation, tissue disorganization and functional ablation. In tight cooperation with other phagocytosis receptors, MERTK—a member of the TAM family of receptor tyrosine kinases (RTK)—plays a pivotal role in apoptotic substrate cleaning from the retina, the testis and the ovaries through unconventional autophagy-assisted phagocytosis process LAP (LC3-associated phagocytosis). In this review, we focus on the interplay between TAM RTKs, autophagy-related proteins, LAP, and Toll-like receptors (TLR), as well as the regulatory mechanisms allowing these components to sustain tissue homeostasis and prevent functional ablation of the retina, the testis and the ovaries.

Dysregulated cytokine profile associated with biochemical premature ovarian insufficiency

Problem

Premature ovarian insufficiency (POI) imposes great challenge on female reproduction. Whether immune disturbance in ovarian environment was implicated in POI remains unclear. We aimed to characterize the cytokine profile in follicular fluid (FF) and paired serum in patients with biochemical POI (bPOI).

Method of study

Multiplex immunoassay containing 45 cytokines was performed for individual FF and paired serum samples from 35 bPOI patients and 37 matched controls. Cytokine profiles were compared between the two groups and cytokines correlated to ovarian reserve, and the rates of day‐3 good‐quality embryos were further analyzed.

Results

In FF, significantly elevated level of chemokines MIP‐1α (P = .043), CXCL8 (P = .024), IP‐10 (P = .041), and eotaxin‐1 (P = .015) as well as growth factors VEGF‐D (P = .047), BDNF (P = .043), LIF (P = .002), and bFGF (P = .046) was found in bPOI patients compared to controls. Yet RANTES manifested an opposite trend with reduced levels among bPOI patients (P = .006). All these chemokines and growth factors in FF were significantly correlated with ovarian reserve (P < .05). In paired serum, cytokine signature was not likely accordant with that in FF between two groups, except for increased IP‐10 (P = .032) in bPOI patients and its significant correlation to FSH and AFC (P < .05). Among all differentially expressed cytokines, RANTES in FF was correlated with the rate of day‐3 good‐quality embryos (P = .035).

Conclusion

Altered cytokine profile characterized by increased chemokines and growth factors was associated with early stage of POI, which may fuel the progression of the disease or even play a crucial role in the development of ovarian insufficiency.