Hyperactive CREB signaling pathway involved in the pathogenesis of polycystic ovarian syndrome revealed by patient-specific induced pluripotent stem cell modeling

3D organoid cultivation improves the maturation and functional differentiation of cholangiocytes from human pluripotent stem cells

Idiopathic cholangiopathies are diseases that affect cholangiocytes, and they have unknown etiologies. Currently, orthotopic liver transplantation is the only treatment available for end-stage liver disease. Limited access to the bile duct makes it difficult to model cholangiocyte diseases. In this study, by mimicking the embryonic development of cholangiocytes and using a robust, feeder- and serum-free protocol, we first demonstrate the generation of unique functional 3D organoids consisting of small and large cholangiocytes derived from human pluripotent stem cells (PSCs), as opposed to traditional 2D culture systems. At day 28 of differentiation, the human PSC-derived cholangiocytes expressed markers of mature cholangiocytes, such as CK7, CK19, and cystic fibrosis transmembrane conductance regulator (CFTR). Compared with the 2D culture system-generated cholangiocytes, the 3D cholangiocyte organoids (COs) showed higher expression of the region-specific markers of intrahepatic cholangiocytes YAP1 and JAG1 and extrahepatic cholangiocytes AQP1 and MUC1. Furthermore, the COs had small-large tube-like structures and functional assays revealed that they exhibited characteristics of mature cholangiocytes, such as multidrug resistance protein 1 transporter function and CFTR channel activity. In addition to the extracellular matrix supports, the epidermal growth factor receptor (EGFR)-mediated signaling regulation might be involved in this cholangiocyte maturation and differentiation. These results indicated the successful generation of intrahepatic and extrahepatic cholangiocytes by using our 3D organoid protocol. The results highlight the advantages of our 3D culture system over the 2D culture system in promoting the functional differentiation and maturation of cholangiocytes. In summary, in advance of the previous works, our study provides a possible concept of small-large cholangiocyte transdifferentiation of human PSCs under cost-effective 3D culture conditions. The study findings have implications for the development of effective cell-based therapy using COs for patients with cholangiopathies.

Synthetic human gonadal tissues for toxicology

The process of mammalian reproduction involves the development of fertile germ cells in the testis and ovary, supported by the surrounders. Fertilization leads to embryo development and ultimately the birth of offspring inheriting parental genome information. Any disruption in this process can result in disorders such as infertility and cancer. Chemical toxicity affecting the reproductive system and embryogenesis can impact birth rates, overall health, and fertility, highlighting the need for animal toxicity studies during drug development. However, the translation of animal data to human health remains challenging due to interspecies differences. In vitro culture systems offer a promising solution to bridge this gap, allowing the study of mammalian cells in an environment that mimics the physiology of the human body. Current advances on in vitro culture systems, such as organoids, enable the development of biomaterials that recapitulate the physiological state of reproductive organs. Application of these technologies to human gonadal cells would provide effective tools for drug screening and toxicity testing, and these models would be a powerful tool to study reproductive biology and pathology. This review focuses on the 2D/3D culture systems of human primary testicular and ovarian cells, highlighting the novel approaches for in vitro study of human reproductive toxicology, specifically in the context of testis and ovary.

Induced Pluripotent Stem Cells as a Possible Approach for Exploring the Pathophysiology of Polycystic Ovary Syndrome (PCOS)

Polycystic ovary syndrome (PCOS) is the most prevalent endocrine condition among women with pleiotropic sequelae possessing reproductive, metabolic, and psychological characteristics. Although the exact origin of PCOS is elusive, it is known to be a complex multigenic disorder with a genetic, epigenetic, and environmental background. However, the pathogenesis of PCOS, and the role of genetic variants in increasing the risk of the condition, are still unknown due to the lack of an appropriate study model. Since the debut of induced pluripotent stem cell (iPSC) technology, the ability of reprogrammed somatic cells to self-renew and their potential for multidirectional differentiation have made them excellent tools to study different disease mechanisms. Recently, researchers have succeeded in establishing human in vitro PCOS disease models utilizing iPSC lines from heterogeneous PCOS patient groups (iPSCPCOS). The current review sets out to summarize, for the first time, our current knowledge of the implications and challenges of iPSC technology in comprehending PCOS pathogenesis and tissue-specific disease mechanisms. Additionally, we suggest that the analysis of polygenic risk prediction based on genome-wide association studies (GWAS) could, theoretically, be utilized when creating iPSC lines as an additional research tool to identify women who are genetically susceptible to PCOS. Taken together, iPSCPCOS may provide a new paradigm for the exploration of PCOS tissue-specific disease mechanisms.

Role of genomic DNA methylation in PCOS pathogenesis: a systematic review and meta-analysis involving case controlled clinical studies

PCOS is often associated with aberrant DNA methylation. Despite the advances in diagnostics and treatment of PCOS, the pathophysiological mechanism remain unknown. Several genes are epigenetically dysregulated in PCOS and associated with pathological consequences of PCOS and metabolic comorbidities, however the methylation status of specific genes and to what extent the genes are deregulated in terms of methylation pattern are unknown. This review aimed to analyse the existing data for specific genes and find conclusive evidence of their involvement in PCOS and associated risks. A comprehensive literature search was conducted in five electronic databases. The case-controlled clinical studies using both PCOS and healthy women and evaluating the methylation pattern without any treatment or intervention were included in the study. A random-effect model was used to extract the data for meta-analysis, and outcomes were expressed as standardized mean difference with a 95% CI. From 541 screened records, 41 studies were included in the review and 21 of them were used for meta-analysis of 20 genes. Meta-analysis revealed a significant global DNA hypomethylation in different tissues and peripheral blood of patients with PCOS compared to healthy controls. Specific gene methylation assessment revealed that genes associated with several functions were significantly hypomethylated and hypermethylated in patients with PCOS. This review provides conclusive evidence of epigenetic deregulation of specific genes in PCOS. These genes can potentially be used to develop diagnostic biomarkers or as targets for personalised therapy.

Randomized controlled trial of astaxanthin impacts on antioxidant status and assisted reproductive technology outcomes in women with polycystic ovarian syndrome

PURPOSE

Polycystic ovary syndrome (PCOS), the most common endocrinopathy in women, is typically accompanied by a defective oxidative defense system. Here, we investigated the effect of astaxanthin (AST) as a powerful antioxidant on the oxidative stress (OS) response and assisted reproductive technology (ART) outcomes in PCOS patients.

METHODS

In this double-blind, randomized, placebo-controlled trial, PCOS patients were randomly assigned into two groups. The intervention group received 8 mg AST, and the control group received the placebo daily for 40 days. The primary outcomes were the serum and follicular fluid (FF) levels of the OS biomarkers and the expression levels of the specific genes and proteins in the oxidative stress response pathway. The secondary outcomes were considered ART outcomes.

RESULTS

According to our findings, a 40-day course of AST supplementation led to significantly higher levels of serum CAT and TAC in the AST group compared to the placebo group. However, there were no significant intergroup differences in the serum MDA and SOD levels, as well as the FF levels of OS markers. The expression of Nrf2, HO-1, and NQ-1 was significantly increased in the granulosa cells (GCs) of the AST group. Moreover, the MII oocyte and high-quality embryo rate were significantly increased in the AST group compared to the placebo group. We found no significant intergroup difference in the chemical and clinical pregnancy rates.

CONCLUSION

AST treatment has been shown to increase both serum TAC levels and activation of the Nrf2 axis in PCOS patients' GCs.

TRIAL REGISTRATION

ClincialTrials.gov Identifier: NCT03991286.

Metabolic Syndrome in Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a common endocrinopathy in women of reproductive age. Although its essential clinical manifestation includes a plethora of symptoms and signs, which largely reflects the underlying hyperandrogenism, oligo/anovulation, and polycystic ovarian morphology, PCOS may also be associated with many metabolic derangements. These metabolic derangements happen to overlap with many of the core constituents of the metabolic syndrome (MBS)—increased insulin resistance, central obesity, and dyslipidemia. The two disorders also display similarly increased risks for certain metabolic and vascular diseases, such as type 2 diabetes mellitus, hypertension, and cardiovascular diseases. Due to the many similarities between metabolic syndrome and PCOS, this review aims to examine the evidence concerning the overlapping features, the risks for comorbidities, possible shared mechanisms, and treatment strategies in patients with coexisting PCOS and MBS.

Regenerative Medicine Perspectives in Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is the most common gynecologic endocrine disorder in women between the ages of 15 and 40, with uncertain etiology. It is mostly presented with hyperandrogenism and insulin resistance along with a variety of comorbidities that significantly reduce a patient's quality of life. Many disturbed metabolic pathways are correlated with PCOS. Moreover, it is evident that there is a strong genetic factor for PCOS. Indeed, several altered gene expressions have been found in PCOS subjects, but the exact genetic origins are still unclear. The major treatment options such as pharmacological treatments are to improve the symptoms. In addition, surgical procedures (Bariatric surgery and assisted reproductive technologies) can be used to treat some of the patient's complications and reduce their severity. Generally, using pharmacological agents for a long period of time can increase the risk of adverse effects. Moreover, surgical options may have high-risk consequences. Herein, there is an undeniable need for a different multidisciplinary approach to PCOS. Regenerative medicine with the help of stem cells can develop a worthy alternative approach for the treatment of PCOS. Furthermore, animal models can provide valuable knowledge of genetic alterations and metabolic pathway disturbances in PCOS. They can also be used for testing novel treatments in pre-clinical stages. Therein, the current knowledge of PCOS and investigation about the potential role of regenerative medicine in developing new and more efficient treatments for PCOS are summarized here.

Melatonin stimulates aromatase expression and estradiol production in human granulosa-lutein cells: relevance for high serum estradiol levels in patients with ovarian hyperstimulation syndrome

Ovarian hyperstimulation syndrome (OHSS) is one of the most life-threatening and potentially fatal complications associated with controlled ovarian hyperstimulation (COH) during in vitro fertilization (IVF) treatment. Although the pathogenesis of OHSS remains unclear, elevated serum estradiol (E2) levels before human chorionic gonadotropin (hCG) administration are associated with the risk of OHSS. The pineal hormone melatonin and its receptors are expressed in human granulosa cells and have been shown to stimulate E2 production. However, the effect of melatonin on the expression of aromatase, an enzyme responsible for a key step in the biosynthesis of E2, in human granulosa cells remains to be determined. Here, we demonstrate that melatonin upregulates aromatase expression in primary cultured human granulosa-lutein (hGL) cells through the melatonin receptor-mediated PKA-CREB pathway. Using a mouse model of OHSS, we demonstrate that administration of the melatonin receptor inhibitor luzindole inhibits the development of OHSS. In addition, the expression of ovarian aromatase and serum E2 levels are upregulated in OHSS mice compared to control mice, but this upregulation is attenuated by inhibition of the function of melatonin. Moreover, clinical results reveal that aromatase expression levels are upregulated in hGL cells from OHSS patients. Melatonin and E2 levels in the follicular fluid are significantly higher in OHSS patients than in non-OHSS patients. Furthermore, melatonin levels are positively correlated with E2 levels in follicular fluid. This study helps to elucidate the mechanisms mediating the expression of aromatase in hGL cells and provides a potential mechanism explaining the high E2 levels in patients with OHSS.

Blocking the activity of melatonin helps prevent female mice from developing swollen ovaries, a potentially life-threatening complication of assisted fertilization techniques. A research team from China’s First Affiliated Hospital of Zhengzhou University, led by Jung-Chien Cheng and Ying-Pu Sun, demonstrated that melatonin, a hormone found in the fluid that surrounds developing eggs, can induce ovarian cells to boost expression of aromatase. This enzyme is responsible for synthesizing estradiol, a hormone involved in female reproduction. Women whose ovaries became over-stimulated in response to fertility medications showed elevated levels of melatonin, aromatase and estradiol. Inhibiting the function of melatonin reduced symptoms in mouse models of ovarian hyperstimulation syndrome. The findings reveal an important role of melatonin in ovarian enlargement and point to new therapeutic strategies for women undergoing in vitro fertilization.