Alterations in the intestinal microbiome associated with PCOS affect the clinical phenotype. Biomed Pharmacother. 2021;133:110958. [PMID: 33171400 DOI: 10.1016/j.biopha.2020.110958]

Gut microbiota in diabetic-linked polycystic ovarian syndrome: Mechanisms and therapeutic insights

Polycystic ovarian syndrome (PCOS) is a complex multisystem disorder prevalent among women of reproductive age, commonly marked by insulin resistance, hyperinsulinemia, and metabolic disruptions such as hypertension and dyslipidemia, which elevate risks of cardiovascular disease and hepatic steatosis. Recent advances underscore the gut microbiome's critical role in modulating insulin resistance and metabolic homeostasis in PCOS. This review highlights novel insights into gut dysbiosis-driven inflammation, gut-brain hormonal signaling, and immune modulation as underlying mechanisms connecting PCOS with metabolic dysfunction and diabetes. We comprehensively analyzed studies up to September 2024 on gut microbiota, diabetes, PCOS, and metformin, exploring emerging perspectives on the microbiome's therapeutic potential in managing PCOS. Metformin's dual role in insulin sensitivity improvement and gut microbiome modulation is emphasized, including its indirect effects on weight management. This review also identifies gaps in current research, urging a shift toward precision therapies targeting microbiome-related pathways in PCOS. Further exploration of the gut-brain axis, pathogen-associated molecular patterns, and the need for controlled clinical trials are discussed to enhance therapeutic approaches.

Gut microbiota: an emerging target connecting polycystic ovarian syndrome and insulin resistance

Polycystic ovary syndrome (PCOS) is a highly heterogeneous metabolic disorder, with oligomenorrhea and hirsutism as patients' primary complaints. Hyperinsulinemia is a crucial pathophysiological mechanism in the development of PCOS, with 50-70% of patients exhibiting insulin resistance (IR). This condition not only exacerbates ovulatory dysfunction but also leads to various adverse metabolic outcomes, such as dyslipidemia and diabetes, and increases the risk of cardiovascular events both before and after menopause. Gut microbiota is a microbial community within the host that possesses significant metabolic potential and is shaped by external environmental factors, the neuro-immune network, and metabolism. Recent studies have shown that gut microbiota dysbiosis is closely related to the development and progression of PCOS. Despite the growing recognition of the potential role of gut microbiota in the pathogenesis and treatment of PCOS, its clinical application remains in its infancy. Currently, most clinical guidelines and expert consensus still emphasize traditional therapeutic approaches, such as hormonal treatments, lifestyle modifications, and insulin sensitizers. However, accumulating evidence suggests that gut microbiota may influence the metabolic and reproductive health of PCOS patients through various mechanisms. Therefore, understanding the role of gut microbiota between PCOS and IR is essential. This review describes the changes in the gut microbiota of IR-PCOS patients, examines the potential mechanisms by which the gut microbiota contributes to IR in PCOS patients, and updates the evidence supporting the gut microbiota as a potential metabolic regulatory target in IR-PCOS. In summary, gut microbiota dysbiosis may be involved in the development and progression of IR in PCOS patients, and improving gut microbiota may offer metabolic stability benefits.

TGF-β signaling in the ovary: Emerging roles in development and disease

The TGF-β superfamily plays a pivotal role in a wide array of cellular processes, including cell proliferation, differentiation, apoptosis, and migration. It is also critically involved in ovarian development and the pathogenesis of various diseases. Within the ovary, follicles act as the primary functional units, housing numerous members of the TGF-β superfamily that regulate follicular development and, consequently, overall ovarian function. Dysregulation of the TGF-β signaling pathway is associated with reproductive disorders and the development of ovarian diseases in female mammals, such as polycystic ovary syndrome (PCOS), premature ovarian aging, ovarian insufficiency, and ovarian cancer. This article highlights the significant contributions of key TGF-β signaling pathway members to follicular development and ovarian disease progression, aiming to deepen the understanding of TGF-β signaling's critical role in reproductive health.

Probiotic supplement for the treatment of polycystic ovarian syndrome

Polycystic Ovarian Syndrome is one of the major prevalent causes of infertility reported worldwide nearly 6-26 %, especially in girls hitting puberty and women at their childbearing age. The main clinical manifestations include irregular menstrual cycle, small cysts on one or both ovaries, chronic oligo-anovulation, and hirsutism. The etiological criteria are very complex and related to many factors like obesity, insulin sensitivity, inflammation, hyperandrogenism, diabetes mellitus type II, cardiovascular diseases, and dysbiosis of gut microbiota. The given review focuses on managing PCOS through probiotics by analyzing the effects on the symptoms of the disease. The probiotics effective in treating PCOS belong to Bifidobacterium, Lactobacilli, Clostridium, Enterococcus, and other Lactic acid bacteria. Its significance in PCOS is mainly due to the antagonizing of the growth of pathogenic microorganisms, increasing intestinal mucus layer production, reducing intestinal permeability, and modulating the gastrointestinal immune system. Also, their interaction with certain hormones such as insulin, androgen, and estrogen through short-chain fatty acids influences fertility. More research is necessary to validate these results. Probiotic supplements could be a viable option for treating PCOS in adults.

Leonurine restrains granulosa cell ferroptosis through SLC7A11/GPX4 axis to promote the treatment of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common endocrine disorder marked by ovarian dysfunction and metabolic abnormality. This study explores the therapeutic potential of leonurine (SCM-198) in PCOS. Our results show that SCM-198 treatment significantly improved ovarian function, hormone disorders and insulin resistance while reducing granulosa cell ferroptosis. This study provides the first evidence that SCM-198 modulates the gut microbiota composition, increases the abundance of Christensenella minuta, and boosts butyrate levels. Transcriptomic and metabolomic analyses revealed that PCOS patients exhibit granulosa cell ferroptosis and decreased butyrate levels in follicular fluid. Butyrate was shown to alleviate ferroptosis in granulosa cells via the SLC7A11/TXNRD1/GPX4 pathway, as confirmed in vitro with KGN cells. The therapeutic mechanism of SCM-198 in the management of PCOS via the gut microbiota-ovary axis involves the enhancement of gut microbiota and its metabolites. This intervention improves ovarian function and alleviates PCOS symptoms by targeting ferroptosis in granulosa cells.

Polycystic ovary syndrome: Recent research and therapeutic advancements

Polycystic ovary syndrome is often characterized by the appearance of several tiny cysts (fluid-filled sacs) in the ovaries. It is the most significant endocrinopathy affecting 8-13 % of women during their lifetime. Within the dynamic domain of women's health, this syndrome is a widespread issue that presents with an array of signs, including insulin resistance, hirsutism, androgen development, and menstrual flaws prompted by genetic, diet/lifestyle, gut microbiota dysbiosis, and environmental toxins. Impaired folliculogenesis, aberrant cortisol metabolism, and genes associated with steroidogenesis contribute to the pathophysiology of the disease. Moreover, it combines with various concurrent metabolic and idiopathic conditions specifically type 2 diabetes, heart disease, cancer, and infertility. On persuading the reproductive framework of women from ontogeny to menopause, the complexity of the syndrome hereditates generations due to maternal inheritance of hyperandrogenism. The advancement in diagnostic norms paved the way from the Rotterdam criteria to metabolomics, 3D ultrasound, and assisted reproductive technologies. The management and treatment of this hormonal disorder can be prevailed through lifestyle modifications and prompt medications. This review entails the aforementioned benchmarks of the syndrome's complexity and its ongoing research in alleviating its intricate behavioral changes in women from in-utero to menopause.

The Novel Insight of Gut Microbiota from Mouse Model to Clinical Patients and the Role of NF-κB Pathway in Polycystic Ovary Syndrome

Polycystic Ovary Syndrome (PCOS) is a metabolic disorder characterized by hyperandrogenism and related symptoms in women of reproductive age. Emerging evidence suggests that chronic low-grade inflammation plays a significant role in the development of PCOS. The gut microbiota, a complex bacterial ecosystem, has been extensively studied for various diseases, including PCOS, while the underlying mechanisms are not fully understood. This review comprehensively summarizes the changes in gut microbiota and metabolites observed in PCOS and their potential association with the condition. Additionally, we discuss the role of abnormal nuclear factor κB signaling in the pathogenesis of PCOS. These findings offer valuable insights into the mechanisms of PCOS and may pave the way for the development of control and therapeutic strategies for this condition in clinical practice. By bridging the gap between mouse models and clinical patients, this review contributes to a better understanding of the interplay between gut microbiota and inflammation in PCOS, thus paving new ways for future investigations and interventions.

Transcription repression of estrogen receptor alpha by ghrelin/Gq/11/YAP signaling in granulosa cells promotes polycystic ovary syndrome

Polycystic ovarian syndrome (PCOS) is a prevalent endocrinological disorder affected by ghrelin. This study aimed to investigate the molecular mechanisms underlying the effects of ghrelin on PCOS manifestations in mice and to assess the therapeutic potential of ghrelin. Female C57BL/6 mice were subcutaneously injected with 6 mg/100 g dehydroepiandrosterone (DHEA) for 20 days to induce PCOS. Alterations in reproductive cycles, ovarian morphology, serum sex hormone levels, and related signaling markers were examined. Furthermore, ghrelin-induced effects on granulosa cells and the role of ghrelin/Gq/11/ Yes-associated protein (YAP) signaling were studied by silencing Gαq/11 or YAP using si-RNAs. Finally, we evaluated the therapeutic potential of anti-ghrelin antibodies in DHEA-induced PCOS mice. DHEA administration led to significant PCOS-associated changes including weight gain, disrupted estrous cycles, ovarian morphological alterations, and hormonal imbalances in mice, with elevated Gαq/11 and acylated ghrelin expression, which was also noted in PCOS patients. However, treatment with anti-ghrelin antibodies effectively managed DHEA-induced damage in PCOS mice. In vitro, ghrelin exposure resulted in granulosa cell injury and modulated estrogen receptors alpha (ERα) and YAP protein levels, whereas silencing YAP and Gαq/11 reversed ghrelin-induced detrimental effects and up-regulated ERα expression. This study revealed that DHEA-induced PCOS traits in mice could be improved by anti-ghrelin antibodies, with the ghrelin/Gq/11/YAP signaling pathway identified as a crucial mediator in granulosa cells, affecting ERα transcription to regulate PCOS. These findings suggest a potential therapeutic strategy for the treatment of PCOS.

The vaginal metabolomics profile with features of polycystic ovary syndrome: a pilot investigation in China

Background

Polycystic ovary syndrome (PCOS) is the most common metabolic disorder and reproductive endocrine disease, posing an elevated risk to women of reproductive age. Although metabolism differences in serum, amniotic fluid and urine have been documented in PCOS, there remains a paucity of evidence for vaginal fluid. This study aimed to identify the metabolic characteristics and potential biomarkers of PCOS in Chinese women of reproductive age.

Methods

We involved ten newly diagnosed PCOS women who attended gynecology at Zhongda Hospital and matched them with ten healthy controls who conducted health check-up programs at Gulou Maternal and Child Health Center in Nanjing, China from January 1st, 2019 to July 31st, 2020. Non-targeted metabolomics based on ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) was applied to differentially screen vaginal metabolites between PCOS group and healthy controls. Principal component analysis (PCA), orthogonal partial least-squares discriminant analysis (OPLS-DA) and enrichment analysis were used to observe differences, search for potential biomarkers and enrich related pathways.

Results

Among the 20 participants, a total of 195 different metabolites were detected between PCOS group and healthy control group. PCOS and control groups were effectively separated by vaginal fluid. Lipids and lipid-like molecules constituted the majority of differential metabolites. Notably, dopamine exhibited an increased trend in PCOS group and emerged as the most significant differential metabolite, suggesting its potential as a biomarker for identifying PCOS. The application of UHPLC-MS/MS based vaginal metabolomics methods showed significant differences between PCOS and non-PCOS healthy control groups, especially linoleic acid metabolism disorder. Most differential metabolites were enriched in pathways associated with linoleic acid metabolism, phenylalanine metabolism, tyrosine metabolism, nicotinate and nicotinamide metabolism or arachidonic acid metabolism.

Conclusions

In this pilot investigation, significant metabolomics differences could be obtained between PCOS and healthy control groups. For PCOS women of reproductive age, vaginal metabolism is a more economical, convenient and harmless alternative to provide careful personalized health diagnosis and potential targets for therapeutic intervention.

Disclosing α-lactalbumin impact on the intestinal and vaginal microbiota of women suffering from polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is one of the most widespread endocrinopathy affecting women of reproductive age with detrimental effects on life quality and health. Among several mechanisms involved in its aetiopathogenesis, recent studies have also postulated the involvement of the vaginal and intestinal microbiota in the development of this disorder. In this study, an accurate insight into the microbial changes associated with PCOS was performed through a pooled-analysis highlighting that this syndrome is characterized by intestinal and vaginal dysbiosis with a reduction of beneficial microorganisms and a higher proportion of potential pathogens. Based on this observation, we evaluated the ability of a milk-derived protein exerting positive outcomes in the management of PCOS, that is, α-lactalbumin (α-LA), to recover PCOS-related dysbiosis. In vitro experiments revealed that this protein improved the growth performances of members of two health-promoting bacterial genera, that is, Bifidobacterium and Lactobacillus, depleted in both intestinal and vaginal microbiota of PCOS-affected women. In addition, α-LA modulated the taxonomic composition and growth performances of the microbial players of the complex intestinal and vaginal microbiota. Finally, an in vivo pilot study further corroborated these observations. The oral administration of α-LA for 30 days to women with PCOS revealed that this protein may have a role in favouring the growth of health-promoting bacteria yet limiting the proliferation of potential pathogens. Overall, our results could pave the way to the use of α-LA as a valid compound with 'prebiotic effects' to limit/restore the PCOS-related intestinal and vaginal dysbiosis.

Fecal microbiota transplantation from patients with polycystic ovary syndrome induces metabolic disorders and ovarian dysfunction in germ-free mice

BACKGROUND

Dysbiosis of the microbiome is a key hallmark of polycystic ovary syndrome (PCOS). However, the interaction between the host and microbiome and its relevance to the pathogenesis of PCOS remain unclear.

METHODS

To evaluate the role of the commensal gut microbiome in PCOS, we gavaged germ-free mice with the fecal microbiota from patients with PCOS or healthy individuals and evaluated the reproductive endocrine features of the recipient mice.

RESULTS

Mice transplanted with fecal microbiota from PCOS patients and those transplanted from healthy controls presented different bacterial profiles and reproductive endocrine features. The fecal microbiota of the mice in the PCOS group was enriched in Phocaeicola, Mediterraneibacter, Oscillospiraceae, Lawsonibacter and Rikenellaceae. Fecal microbiota transplantation (FMT) from PCOS patients induced increased disruption of ovarian functions, lipo-metabolic disturbance, insulin resistance and an obese-like phenotype in recipient mice.

CONCLUSION

Our findings suggest that the microbiome may govern the set point of PCOS-bearing individuals and that gut ecosystem manipulation may be a useful marker and target for the management of PCOS.

The Beneficial Effects of Lacticaseibacillus paracasei subsp. paracasei DSM 27449 in a Letrozole-Induced Polycystic Ovary Syndrome Rat Model

Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder affecting women of reproductive age globally. Emerging evidence suggests that the dysregulation of microRNAs (miRNAs) and gut dysbiosis are linked to the development of PCOS. In this study, the effects of Lacticaseibacillus paracasei subsp. paracasei DSM 27449 (DSM 27449) were investigated in a rat model of PCOS induced by letrozole. The administration of DSM 27449 resulted in improved ovarian function, reduced cystic follicles, and lower serum testosterone levels. Alterations in miRNA expressions and increased levels of the pro-apoptotic protein Bax in ovarian tissues were observed in PCOS-like rats. Notably, the administration of DSM 27449 restored the expression of miRNAs, including miR-30a-5p, miR-93-5p, and miR-223-3p, leading to enhanced ovarian function through the downregulation of Bax expressions in ovarian tissues. Additionally, 16S rRNA sequencing showed changes in the gut microbiome composition after letrozole induction. The strong correlation between specific bacterial genera and PCOS-related parameters suggested that the modulation of the gut microbiome by DSM 27449 was associated with the improvement of PCOS symptoms. These findings demonstrate the beneficial effects of DSM 27449 in ameliorating PCOS symptoms in letrozole-induced PCOS-like rats, suggesting that DSM 27449 may serve as a beneficial dietary supplement with the therapeutic potential for alleviating PCOS.

Metformin modifies plasma microbial-derived extracellular vesicles in polycystic ovary syndrome with insulin resistance

INTRODUCTION

This study investigated changes in plasma microbial-derived extracellular vesicles (EVs) in patients with polycystic ovary syndrome and insulin resistance (PCOS-IR) before and after metformin treatment, and aimed to identify bacterial taxa within EVs that were biologically and statistically significant for diagnosis and treatment.

METHODS

The case-control study was conducted at Xiamen Chang Gung Hospital, Hua Qiao University. Plasma samples were collected from five PCOS-IR patients of childbearing age before and after 3 months of metformin treatment, and the samples were sequenced. The diversity and taxonomic composition of different microbial communities were analyzed through full-length 16 S glycosomal RNA gene sequencing.

RESULTS

After metformin treatment, fasting plasma glucose levels and IR degree of PCOS-IR patients were significantly improved. The 16 S analysis of plasma EVs from metformin-treated patients showed higher microbial diversity. There were significant differences in EVs derived from some environmental bacteria before and after metformin treatment. Notably, Streptococcus salivarius was more abundant in the metformin-treated group, suggesting it may be a potential probiotic.

DISCUSSION

The study demonstrated changes in the microbial composition of plasma EVs before and after metformin treatment. The findings may offer new insights into the pathogenesis of PCOS-IR and provide new avenues for research.

Gut Microbiome and Polycystic Ovary Syndrome: Interplay of Associated Microbial-Metabolite Pathways and Therapeutic Strategies

Polycystic ovary syndrome (PCOS) is a multifaceted disease with an intricate etiology affecting reproductive-aged women. Despite attempts to unravel the pathophysiology, the molecular mechanism of PCOS remains unknown. There are no effective or suitable therapeutic strategies available to ameliorate PCOS; however, the symptoms can be managed. In recent years, a strong association has been found between the gut microbiome and PCOS, leading to the formulation of novel ideas on the genesis and pathological processes of PCOS. Further, gut microbiome dysbiosis involving microbial metabolites may trigger PCOS symptoms via many mechanistic pathways including those associated with carbohydrates, short-chain fatty acids, lipopolysaccharides, bile acids, and gut-brain axis. We present the mechanistic pathways of PCOS-related microbial metabolites and therapeutic opportunities available to treat PCOS, such as prebiotics, probiotics, and fecal microbiota therapy. In addition, the current review highlights the emerging treatment strategies available to alleviate the symptoms of PCOS.

Fusobacterium nucleatum: An Overview of Evidence, Demi-Decadal Trends, and Its Role in Adverse Pregnancy Outcomes and Various Gynecological Diseases, including Cancers

Gynecological and obstetric infectious diseases are crucial to women's health. There is growing evidence that links the presence of Fusobacterium nucleatum (F. nucleatum), an anaerobic oral commensal and potential periodontal pathogen, to the development and progression of various human diseases, including cancers. While the role of this opportunistic oral pathogen has been extensively studied in colorectal cancer in recent years, research on its epidemiological evidence and mechanistic link to gynecological diseases (GDs) is still ongoing. Thus, the present review, which is the first of its kind, aims to undertake a comprehensive and critical reappraisal of F. nucleatum, including the genetics and mechanistic role in promoting adverse pregnancy outcomes (APOs) and various GDs, including cancers. Additionally, this review discusses new conceptual advances that link the immunomodulatory role of F. nucleatum to the development and progression of breast, ovarian, endometrial, and cervical carcinomas through the activation of various direct and indirect signaling pathways. However, further studies are needed to explore and elucidate the highly dynamic process of host-F. nucleatum interactions and discover new pathways, which will pave the way for the development of better preventive and therapeutic strategies against this pathobiont.

Alteration of Plasma Indoles in Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is one of the most common endocrinopathies in reproductive-aged women. The occurrence of PCOS was reported to be associated with the alteration of gut microbiota. Microbiota-derived indoles may possibly play a key role in glycemic control. The purpose of this work is to reveal the alteration of plasma indoles in PCOS patients and to investigate the correlation between indoles levels and glucose metabolism. Sixty-five patients with PCOS and twenty-eight age-matched women were enrolled in this work. The concentrations of plasma indoles, including indoxyl sulfate (IS), indole-3-acetic acid (IAA), indole-3-propionate (IPA), indole (IND), and 3-methylindole (3-MI), were measured by HPLC with the fluorescence detection. The plasma levels of IS, IAA, and IND were significantly elevated in patients with PCOS compared to those in the control group (p < 0.05). Furthermore, the plasma levels of IS, IAA, and IND were positively correlated with fasting glucose, fasting insulin, and the homeostatic model of insulin resistance index (HOMA-IR) (p < 0.05). Besides, the 3-MI level in the plasma was positively correlated with the fasting glucose level, whereas plasma levels of IS, IAA, IND, and 3-MI were negatively correlated with glucagon-like peptide 1 (p < 0.05). Moreover, IS and IND were considered to be risk factors for PCOS after age, BMI, T, LH, and HOMA-IR adjustment. The area under the receiver-operating characteristic curve of the combined index of five indoles was 0.867 for PCOS diagnosis. Additionally, plasma indoles altered in PCOS, which was closely associated with the glucose metabolism.

Polycystic Ovary Syndrome and Irritable Bowel Syndrome: Is There a Common Pathway?

OBJECTIVE

Little is known about how polycystic ovary syndrome (PCOS) is linked to irritable bowel syndrome (IBS). This study aimed to review the existing literature regarding the association between PCOS or its symptoms and complications with IBS.

METHODS

In this review, studies that investigated the proposed cross-link between features of PCOS and IBS were included. This review collectively focused on recent findings on the mechanism and novel insight regarding the association between IBS and PCOS in future clinical practice. An electronic search of PubMed, Scopus, Epistemonikos, Cochrane Library and Google Scholar was performed. We did not restrict the study setting and publication date.

RESULTS

The existing evidence has not completely answered the question of whether there is an association between PCOS and IBS and vice versa. Six case-control studies (793 women with PCOS and 547 women in the control group) directly assessed the association between PCOS and IBS. The prevalence of IBS among women with PCOS in these studies has ranged from 10% to 52% compared with 5%-50% in control groups. Evidence suggested the common pathways may have contributed to the interaction between IBS and PCOS, including metabolic syndrome, sex hormone fluctuation, dysregulation of neurotransmitters, psychological problems and environmental and lifestyle factors. To date, it is still ambiguous which of the mentioned components largely contributes to the pathogenesis of both.

CONCLUSION

Although limited evidence has shown a higher prevalence of IBS in women with PCOS, there are several potential, direct and common indirect pathways contributing to the development of both IBS and PCOS.

Effects of Glucagon-Like Peptide-1 Receptor Agonists on Gut Microbiota in Dehydroepiandrosterone-Induced Polycystic Ovary Syndrome Mice: Compared Evaluation of Liraglutide and Semaglutide Intervention

Purpose

Polycystic ovary syndrome (PCOS) is a frequent cause of infertility in reproductive-age women. Our work aims to evaluate the effects of glucagon-like peptide-1 receptor agonists (GLP-1RAs) on gut microbiota, with metabolic parameters including body weight and the hormone profile in PCOS.

Patients and Methods

Dehydroepiandrosterone (DHEA)-induced PCOS mice were established and then treated with two GLP-1RAs: liraglutide and novel form semaglutide for four weeks. Changes in body weight and metabolic parameters were measured. Fecal samples were collected and analyzed using metagenomic sequencing.

Results

Liraglutide and semaglutide modulated both alpha and beta diversity of the gut microbiota in PCOS. Liraglutide increased the Bacillota-to-Bacteroidota ratio through up-regulating the abundance of butyrate-producing members of Bacillota like Lachnospiraceae. Moreover, liraglutide showed the ability to reverse the altered microbial composition and the disrupted microbiota functions caused by PCOS. Semaglutide increased the abundance of Helicobacter in PCOS mice (p < 0.01) which was the only bacteria found negatively correlated with body weight. Moreover, pathways involving porphyrin and flavonoids were increased after semaglutide intervention.

Conclusion

Liraglutide and semaglutide improved reproductive and metabolic disorders by modulating the whole structure of gut microbiota in PCOS. The greater efficacy in weight loss compared with liraglutide observed after semaglutide intervention was positively related with Helicobacter. The study may provide new ideas in the treatment and the underlying mechanisms of GLP-1RAs to improve PCOS.

Gut microbiota, immunity, and bile acid metabolism: decoding metabolic disease interactions

In recent decades, the global prevalence of metabolic syndrome has surged, posing a significant public health challenge. Metabolic disorders, encompassing diabetes, obesity, nonalcoholic fatty liver disease, and polycystic ovarian syndrome, have been linked to alterations in the gut microbiota. Nonetheless, the connection between gut microbiota and host metabolic diseases warrants further investigation. In this review, we delve into the associations between various metabolic disorders and the gut microbiota, focusing on immune responses and bile acid (BA) metabolism. Notably, T helper cells, innate lymphoid cells, macrophages, and dendritic cells have been shown to modulate host metabolism through interactions with intestinal microorganisms and the release of cytokines. Furthermore, secondary BA metabolites, derived from the microbiota, are involved in the pathogenesis of metabolic diseases via the farnesoid X receptor and Takeda G protein-coupled receptor 5. By covering both aspects of this immune system-microorganism axis, we present a comprehensive overview of the roles played by the gut microbiota, microbiota-derived BA metabolites, and immune responses in metabolic diseases, as well as the interplay between these systems.

The Role of the Gut Microbiome in Youth with Polycystic Ovary Syndrome: A Systematic Review

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common endocrine disorder that affects women of reproductive age and female adolescents. The diagnosis of PCOS is difficult during puberty due to overlapping of the criteria with normal variations of menstruation during this age period. There are insufficient data on the gut microbiome and PCOS and potential mechanisms linking the two. The present systematic review aimed to detect dysbiosis patterns in youth with PCOS, compared with healthy controls.

METHODS

One hundred seventy-eight studies were identified by a databases search and sixty-eight by a full-text assessment for eligibility; four were included in the systematic review and underwent quality control.

RESULTS

The results of the study were controversial in accordance to findings from the literature. A change in gut microbiome α diversity was found in PCOS adolescents, with no significant alterations in β diversity. Almost all studies found Firmicutes, Bacteroidetes, and Actinobacteria in abundance in both groups, with changes in family composition and fluctuations at the phylum level. A statistically significant association between these changes and clinical or biochemical features of the syndrome was described.

CONCLUSIONS

This systematic review confirmed gut microbiota dysbiosis in youth with PCOS. However, further data are needed to clarify these changes and to build a strategy to prevent the syndrome.

Soybean Antigen Protein-Induced Intestinal Barrier Damage by Trigging Endoplasmic Reticulum Stress and Disordering Gut Microbiota in Weaned Piglets

Endoplasmic reticulum (ER) stress is a crucial factor in the pathogenesis of intestinal diseases. Soybean antigenic proteins (β-conglycinin and soy glycinin) induce hypersensitivity reactions and intestinal barrier damage. However, whether this damage is associated with ER stress, autophagy, and the gut microbiome is largely unclear. Therefore, in this study, we aimed to investigate the effect of dietary supplementation with soy glycinin (11S glycinin) and β-conglycinin (7S glycinin) on intestinal ER stress, autophagy, and flora in weaned piglets. Thirty healthy 21-day-old weaned "Duroc × Long White × Yorkshire" piglets were randomly divided into three groups and fed a basic, 7S-supplemented, or 11S-supplemented diet for one week. The results indicated that 7S/11S glycinin disrupted growth performance, damaged intestinal barrier integrity, and impaired goblet cell function in piglets (p < 0.05). Moreover, 7S/11S glycinin induced ER stress and blocked autophagic flux in the jejunum (p < 0.05) and increased the relative abundance of pathogenic flora (p < 0.01) and decreased that of beneficial flora (p < 0.05). In conclusion, 7S/11S glycinin induces intestinal ER stress, autophagic flux blockage, microbiota imbalance, and intestinal barrier damage in piglets.

Circular RNA as a Novel Regulator and Promising Biomarker in Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a prevalent metabolic and reproductive disorder that causes low fertility in females. Despite its detrimental effects on women's health, care for PCOS has been impeded by its undefined pathogenesis. Thus, there is an urgent need to explore novel biomarkers and therapeutic targets for the diagnosis and treatment of PCOS. Circular RNAs (circRNAs) are a class of noncoding RNAs with covalently closed cyclic structures, present in high abundance, and show development-stage specific expression patterns. Recent studies have demonstrated that circRNAs participate in PCOS progression by modulating various biological functions, including cell proliferation, apoptosis, and steroidogenesis. In addition, circRNAs are widely present in the follicular fluid of women with PCOS, indicating their potential as diagnostic biomarkers and therapeutic targets for PCOS. This review provides the current knowledge of circRNAs in PCOS, including their regulatory functions and molecular mechanisms, and explores their potential as diagnostic biomarkers and therapeutic targets.

Expression and Clinical Significance of HIF-1α in Follicular Fluid and Granulosa Cells in Infertile PCOS Patients

The present study aimed to determine the clinical predictive significance of HIF-1α in follicular development and assisted reproductive technology (ART). We collected follicular fluid (FF) and granulosa cells (GCs) from PCOS (polycystic ovary syndrome) patients (experimental group) and other patients who were infertile due to tubal factors or male factors (control group) with IVF/ICSI-ET. The localization and expression of HIF-1α in GCs were determined by immunofluorescence staining. HIF-1α protein and mRNA expression were detected by enzyme-linked immunosorbent assay and quantitative real-time PCR, respectively. To clarify the regulation of HIF-1α by TGF-β1, we added the HIF-1α-specific blocker YC-1 to GCs. The serum AMH, LH, LH/FSH, testosterone, BMI and the number of oocytes retrieved in the PCOS group were significantly higher, while the cleavage rate was significantly lower, than those in the control group. HIF-1α protein was expressed in the cytoplasm of GCs. The expression of HIF-1α protein in the FF of the PCOS group was significantly lower than that in the control group. However, the expression of HIF-1α protein in GCs between the two groups was not significantly different. HIF-1α protein was highly expressed in large FF (follicular diameter ≥ 14 mm). Compared with the control group, the expression of HIF-1α mRNA in GCs of the PCOS group was significantly lower. The results showed a significant positive correlation between HIF-1α and TGF-β1 expression. We found that both HIF-1α and TGF-β1 were involved in the development of PCOS follicular development. The mutual regulation of HIF-1α and TGF-β1 may be one of the important mechanisms of the occurrence and development of PCOS.

Gut Microbiota and Critical Metabolites: Potential Target in Preventing Gestational Diabetes Mellitus?

Gestational diabetes mellitus (GDM) is an intractable issue that negatively impacts the quality of pregnancy. The incidence of GDM is on the rise, becoming a major health burden for both mothers and children. However, the specific etiology and pathophysiology of GDM remain unknown. Recently, the importance of gut microbiota and related metabolic molecules has gained prominence. Studies have indicated that women with GDM have significantly distinct gut microbiota and gut metabolites than healthy pregnant women. Given that the metabolic pathways of gut flora and related metabolites have a substantial impact on inflammation, insulin signaling, glucose, and lipid metabolism, and so on, gut microbiota or its metabolites, such as short-chain fatty acids, may play a significant role in both pathogenesis and progression of GDM. Whereas the role of intestinal flora during pregnancy is still in its infancy, this review aims to summarize the effects and mechanisms of gut microbiota and related metabolic molecules involved in GDM, thus providing potential intervention targets.

The effects of probiotics, prebiotics, and synbiotics on polycystic ovarian syndrome: an overview of systematic reviews

INTRODUCTION

Accumulating evidence has highlighted the critical role of the gut microbiota and its potential action as a regulator of metabolic disorders including insulin resistance, obesity, and systemic inflammation in polycystic ovarian syndrome (PCOS). Microbiota-modulating interventions, such as probiotics, prebiotics, and synbiotics, could be effective in PCOS management.

METHODS

We conducted an overview of systematic reviews (SRs) and meta-analyses to summarize reviews regarding the effectiveness of probiotics/prebiotics/synbiotics on the management of PCOS through a systematic literature search in PubMed, Web of Science, and Scopus databases until September 2021.

RESULTS

Eight SRs and meta-analyses were included in this study. Our overview confirmed that probiotic supplementation had a potentially beneficial effect on some PCOS-related parameters including body mass index (BMI), fasting plasma glucose (FPG), and lipid profiles. Evidence shows that synbiotics in comparison with probiotics were less effective on these parameters. The methodological quality of SRs was assessed using the AMSTAR-2 assessment tool and was determined as high for four SRs, low for two SRs, and critically low for one SR. Due to limited evidence and high heterogeneity of the studies, it remains difficult to identify optimal probiotics strains, prebiotics types, length of duration, and doses.

DISCUSSION

Future clinical trials with higher quality are recommended to clarify the efficacy of probiotics/prebiotics/synbiotics on the management of PCOS and provide more accurate evidence.

E. coli Nissle 1917 ameliorates mitochondrial injury of granulosa cells in polycystic ovary syndrome through promoting gut immune factor IL-22 via gut microbiota and microbial metabolism

Objective

Gut microbiota and its metabolites have regulatory effects on PCOS related ovarian dysfunction and insulin resistance. Escherichia coli Nissle 1917 (EcN) is a genetically controlled probiotic with an excellent human safety record for improving gut microbiome metabolic disorders and immune system disorders. Here we focused to explore the application and effect of probiotic EcN on the gut microbiota-metabolism-IL-22-mitochondrial damage axis in PCOS.

Methods

PCOS mice were constructed with dehydroepiandrosterone (DHEA) and treated with EcN, FMT or IL-22 inhibitors. Clinically control and PCOS subjects were included for further analysis. Serum and follicular fluid supernatant levels of sex hormones, insulin, glucose, cholesterol, and inflammatory factors were detected by ELISA and biochemical reagents. The pathological changes of ovarian tissues were observed by HE staining. The JC-1 level and COX4 gene expression in granulosa cells was detected by ELISA and RT-qPCR. The expressions of progesterone receptor A (PR-A), LC3II/I, Beclin1, p62 and CytC were detected by western blot. The number of autophagosomes in granulosa cells was observed by electron microscopy. 16S rRNA and LC-MS/MS were used to analyze the changes of gut microbiota and metabolism.

Results

EcN promoted the recovery of sex hormone levels and ovarian tissue morphology, promoted the expression of IL-22, COX4 and PR-A in granulosa cells, and inhibited mitophagy in PCOS mice. EcN decreased the number of gut microbiota, and significantly increased the abundance of Adlercreutzia, Allobaculum, Escherichia-Shigella and Ileibacterium in PCOS mice. EcN improved metabolic disorders in PCOS mice by improving Amino sugar and nucleotide sugar metabolism pathways. IL-22 was positively associated with Ileibacterium, Adlercreutzia and Progesterone, negatively associated with RF39, Luteinizing hormone, Testosterone, N-Acetylglucosamin, L-Fucose and N-Acetylmannosamin. FMT reconfirmed that EcN ameliorated mitochondrial damage in granulosa cells of PCOS mice by gut microbiota, but this process was blocked by IL-22 inhibitor. Clinical trials have further demonstrated reduced IL-22 levels and mitochondrial damage in granulosa cells in PCOS patients.

Conclusion

EcN improved IL-22 level and mitochondrial damage of granulosa cells in PCOS mice by promoting the recovery of sex hormone levels and ovarian tissue morphology, inhibiting the amount of gut microbiota, and promoting amino sugar and nucleotide sugar metabolism.

Polycystic ovary syndrome and iron overload: biochemical link and underlying mechanisms with potential novel therapeutic avenues

Polycystic ovary syndrome (PCOS) is an endocrine and metabolic disorder in women with components of significant genetic predisposition and possibly multiple, but not yet clearly defined, triggers. This disorder shares several clinical features with hemochromatosis, a genetically defined inheritable disorder of iron overload, which includes insulin resistance, increased adiposity, diabetes, fatty liver, infertility, and hyperandrogenism. A notable difference between the two disorders, however, is that the clinical symptoms in PCOS appear at much younger age whereas they become evident in hemochromatosis at a much later age. Nonetheless, noticeable accumulation of excess iron in the body is a common finding in both disorders even at adolescence. Hepcidin, the iron-regulatory hormone secreted by the liver, is reduced in both disorders and consequently increases intestinal iron absorption. Recent studies have shown that gut bacteria play a critical role in the control of iron absorption in the intestine. As dysbiosis is a common finding between PCOS and hemochromatosis, changes in bacterial composition in the gut may represent another cause for iron overload in both diseases via increased iron absorption. This raises the possibility that strategies to prevent accumulation of excess iron with iron chelators and/or probiotics may have therapeutic potential in the management of polycystic ovary syndrome.

The Implication of Mechanistic Approaches and the Role of the Microbiome in Polycystic Ovary Syndrome (PCOS): A Review

As a complex endocrine and metabolic condition, polycystic ovarian syndrome (PCOS) affects women's reproductive health. These common symptoms include hirsutism, hyperandrogenism, ovulatory dysfunction, irregular menstruation, and infertility. No one knows what causes it or how to stop it yet. Alterations in gut microbiota composition and disruptions in secondary bile acid production appear to play a causative role in developing PCOS. PCOS pathophysiology and phenotypes are tightly related to both enteric and vaginal bacteria. Patients with PCOS exhibit changed microbiome compositions and decreased microbial diversity. Intestinal microorganisms also alter PCOS patient phenotypes by upregulating or downregulating hormone release, gut-brain mediators, and metabolite synthesis. The human body's gut microbiota, also known as the "second genome," can interact with the environment to improve metabolic and immunological function. Inflammation is connected to PCOS and may be caused by dysbiosis in the gut microbiome. This review sheds light on the recently discovered connections between gut microbiota and insulin resistance (IR) and the potential mechanisms of PCOS. This study also describes metabolomic studies to obtain a clear view of PCOS and ways to tackle it.

Effects of intestinal flora on polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common endocrine disorder in women of reproductive age. Its clinical characteristics are mainly oligo-ovulation or anovulation, hyperandrogenemia (HA) and insulin resistance (IR). PCOS is considered to be one of the main causes of infertility in women of childbearing age, and its pathogenesis is still unclear. Intestinal flora, known as the "second genome" of human beings, is closely related to metabolic diseases, immune diseases and infectious diseases. At the same time, mounting evidence suggests that intestinal flora can regulate insulin synthesis and secretion, affect androgen metabolism and follicular development, and is involved in the occurrence of chronic inflammation and obesity. The imbalance of intestinal flora is caused by the abnormal interaction between intestinal flora and host cells caused by the change of intestinal microbial diversity, which is related to the occurrence and development of PCOS. The adjustment of intestinal flora may be a potential direction for the treatment of PCOS.

The impact of herbal medicine in regulating intestinal flora on female reproductive disorders

As an important part of the human intestinal microecology, the intestinal flora is involved in a number of physiological functions of the host. Several studies have shown that imbalance of intestinal flora and its regulation of the intestinal barrier, intestinal immune response, and intestinal flora metabolites (short-chain fatty acids and bile acids) can affect the development and regression of female reproductive disorders. Herbal medicine has unique advantages in the treatment of female reproductive disorders such as polycystic ovary syndrome, endometriosis and premature ovarian insufficiency, although its mechanism of action is still unclear. Therefore, based on the role of intestinal flora in the occurrence and development of female reproduction-related diseases, the progress of research on the diversity, structure and composition of intestinal flora and its metabolites regulated by botanical drugs, Chinese herbal formulas and active ingredients of Chinese herbal medicines is reviewed, with a view to providing reference for the research on the mechanism of action of Chinese herbal medicines in the treatment of female reproductive disorders and further development of new herbal medicines.

Expression of Serum Omentin, CTRP9, and Vaspin in Patients with Polycystic Ovary Syndrome

Objective

To explore the relationship between serum omentin, C1q/tumor necrosis factor-related protein-9 (CTRP9), and visceral fat-specific serine protease inhibitor (vaspin) levels in different phenotypes in patients with polycystic ovary syndrome (PCOS).

Methods

One hundred PCOS patients treated at our hospital's clinic of reproductive medicine were chosen and included into the research group, and 100 healthy women who came for physical examination during the same time period were included into the control group. According to the definition of obesity by the WHO (body mass index (BMI) ≥25 kg/m²), 100 patients with PCOS were equally divided into obese (study group A) and nonobese (study group B) groups. 100 healthy women were also divided into obese (control group A) and nonobese (control group B) groups with 50 patients each. Comparison among the 4 groups was performed in factors/indicators including the serum omentin, CTRP9, and vaspin levels and biochemical indexes (triglyceride (TG), total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), fasting insulin (FINS), total testosterone, and homeostasis model assessment of insulin resistance (HOMA-IR) levels), and the correlation analysis was conducted with omentin, CTRP9, and vaspin.

Results

There was no significant difference in age, TG, TC, and LDL-C among the 4 groups (P > 0.05). The BMI, WHR, HDL-C, and omentin of the obese phenotype were significantly different from those of the nonobese phenotype (P < 0.05). Among the four groups, FINS, HOMA-IR, and vaspin in group A (obesity) was the highest, and the control group B (nonobese) was the lowest. There was no significant difference in the levels of study group B (nonobese) and control group A (obesity). The level of CTRP9 in the study group was significantly lower than that in the control group (P < 0.05). Taking serum omentin, CTRP9, and vaspin levels of patients in the study group as dependent variables, Pearson correlation analysis showed that the omentin level was negatively correlated with BMI, WHR, FINS, TG, TC, LDL-C, HOMA-IR, and TT levels (P < 0.05) and was positively correlated with the HDL-C level (P < 0.05); CTRP9 level was negatively correlated with BMI, TC, and HOMA-IR (P < 0.05) and was not correlated with age, WHR, FINS, TG, HDL-C, LDL-C, HOMA-IR, and TT levels. The vaspin level was positively correlated with BMI, WHR, FINS, TG, TC, LDL-C, HOMA-IR, and TT levels (P < 0.05) and negatively correlated with HDL-C levels (P < 0.05) and was not correlated with age.

Conclusion

When compared with healthy people, PCOS patients have higher serum vaspin levels and lower CTRP9 levels; BMI, TC, LDL-C, FINS, TG, total testosterone, HDL-C levels, waist-to-hip ratio, and HOMA-IR are all closely related to serum vaspin and CTRP9 levels; increasing serum CTRP9 levels and decreasing vaspin levels help to slow progress and promote prognosis of the disease. Serum omentin level is connected with the obesity index but not with PCOS.

Effects of Bu Shen Hua Zhuo formula on the LPS/TLR4 pathway and gut microbiota in rats with letrozole-induced polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders in gynecology. Traditional Chinese medicine (TCM) is widely used for the treatment of PCOS in China. The Bu Shen Hua Zhuo formula (BSHZF), a TCM decoction, has shown great therapeutic efficacy in clinical practice. However, the mechanism underlying the BSHZF function in PCOS remains unclear. This study aimed to identify the potential mechanisms of action of BSHZF in the treatment of PCOS. PCOS-model rats treated with letrozole were administered different doses of BSHZF, metformin, and 1% carboxymethylcellulose. Serum sex hormones, fasting blood glucose, and fasting insulin levels were measured, and the morphology of the ovaries was observed in each group, including the normal group. The structure and abundance of the gut microbiota in rats were measured using 16S ribosomal RNA gene sequencing. Toll-like receptor 4 (TLR4) and phospho-NF-κB p65 levels in the ovarian tissue of the rats were detected using Western blotting. Furthermore, the levels of lipopolysaccharide (LPS) and inflammatory cytokines TNF-α, IL-6, and IL-8 in the serum of rats were detected by ELISA. The results showed that BSHZF administration was associated with a decrease in body weight, fasting blood glucose, fasting insulin, and testosterone and changes in ovarian morphology in PCOS-model rats. Moreover, BSHZF was associated with an increase in the α-diversity of gut microbiota, decrease in the relative abundance of Firmicutes, and increase in Lactobacillus and short chain fatty acid-producing bacteria (Allobaculum, Bacteroides, Ruminococcaceae_UCG-014). Furthermore, BSHZF may promote carbohydrate and protein metabolism. In addition, BSHZF was associated with a decrease in the serum level of LPS and TLR4 expression, thereby inhibiting the activation of the NF-κB signaling-mediated inflammatory response in ovarian tissue. Therefore, the beneficial effects of BSHZF on PCOS pathogenesis are associated with its ability to normalize gut microbiota function and inhibit PCOS-related inflammation.

Selenium Deficiency Leads to Inflammation, Autophagy, Endoplasmic Reticulum Stress, Apoptosis and Contraction Abnormalities via Affecting Intestinal Flora in Intestinal Smooth Muscle of Mice

Selenium (Se) is a micronutrient that plays a predominant role in various physiological processes in humans and animals. Long-term lack of Se will lead to many metabolic diseases. Studies have found that chronic Se deficiency can cause chronic diarrhea. The gut flora is closely related to the health of the body. Changes in environmental factors can cause changes in the intestinal flora. Our study found that Se deficiency can disrupt intestinal flora. Through 16s high-throughput sequencing analysis of small intestinal contents of mice, we found that compared with CSe group, the abundance of Lactobacillus, Bifidobacterium, and Ileibacterium in the low selenium group was significantly increased, while Romboutsia abundance was significantly decreased. Histological analysis showed that compared with CSe group, the small intestine tissues of the LSe group had obvious pathological changes. We examined mRNA expression levels in the small intestine associated with inflammation, autophagy, endoplasmic reticulum stress, apoptosis, tight junctions, and smooth muscle contraction. The mRNA levels of NF-κB, IκB, p38, IL-1β, TNF-α, Beclin, ATG7, ATG5, LC3α, BaK, Pum, Caspase-3, RIP1, RIPK3, PERK, IRE1, elF2α, GRP78, CHOP2, ZO-1, ZO-2, Occludin, E-cadherin, CaM, MLC, MLCK, Rho, and RhoA in the LSe group were significantly increased. The mRNA levels of IL-10, p62 BcL-2 and BcL-w were significantly decreased in the LSe group compared with the CSe group. These results suggest that changes in the abundance of Lactobacillus, bifidobacterium, ileum, and Romboutsia may be associated with cellular inflammation, autophagy, endoplasmic reticulum stress, apoptosis, tight junction, and abnormal smooth muscle contraction. Intestinal flora may play an important role in chronic diarrhea caused by selenium deficiency.

Evidence-based hormonal, mutational, and endocrine-disrupting chemical-induced zebrafish as an alternative model to study PCOS condition similar to mammalian PCOS model

Polycystic ovarian syndrome (PCOS) causes swollen ovaries in women at reproductive age due to hormonal disorder with small cysts on the outer edges. The cause of the disorder is still yet to be found. Multiple factors have increased PCOS prevalence, hyperandrogenism, oxidative stress, inflammation, and insulin resistance. Various animal PCOS models have been developed to imitate the pathophysiology of PCOS in humans. Zebrafish is one of the most versatile animal experimental models because of the transparency of the embryos, small size, and rapid growth. The zebrafish similarity to higher vertebrates made it a useful non-mammalian model for PCOS drug testing and screening. This review provides an insight into the usage of zebrafish, a non-mammalian model for PCOS, as an opportunity for evaluating future initiatives in such a research domain.

A review of the hormones involved in the endocrine dysfunctions of polycystic ovary syndrome and their interactions

Polycystic ovary syndrome (PCOS) affects up to 20% of women but remains poorly understood. It is a heterogeneous condition with many potential comorbidities. This review offers an overview of the dysregulation of the reproductive and metabolic systems associated with PCOS. Review of the literature informed the development of a comprehensive summarizing 'wiring' diagram of PCOS-related features. This review provides a justification for each diagram aspect from the relevant academic literature, and explores the interactions between the hypothalamus, ovarian follicles, adipose tissue, reproductive hormones and other organ systems. The diagram will provide an efficient and useful tool for those researching and treating PCOS to understand the current state of knowledge on the complexity and variability of PCOS.

Present and Future: Crosstalks Between Polycystic Ovary Syndrome and Gut Metabolites Relating to Gut Microbiota

Polycystic ovary syndrome (PCOS) is a common disease, affecting 8%-13% of the females of reproductive age, thereby compromising their fertility and long-term health. However, the pathogenesis of PCOS is still unclear. It is not only a reproductive endocrine disease, dominated by hyperandrogenemia, but also is accompanied by different degrees of metabolic abnormalities and insulin resistance. With a deeper understanding of its pathogenesis, more small metabolic molecules, such as bile acids, amino acids, and short-chain fatty acids, have been reported to be involved in the pathological process of PCOS. Recently, the critical role of gut microbiota in metabolism has been focused on. The gut microbiota-related metabolic pathways can significantly affect inflammation levels, insulin signaling, glucose metabolism, lipid metabolism, and hormonal secretions. Although the abnormalities in gut microbiota and metabolites might not be the initial factors of PCOS, they may have a significant role in the pathological process of PCOS. The dysbiosis of gut microbiota and disturbance of gut metabolites can affect the progression of PCOS. Meanwhile, PCOS itself can adversely affect the function of gut, thereby contributing to the aggravation of the disease. Inhibiting this vicious cycle might alleviate the symptoms of PCOS. However, the role of gut microbiota in PCOS has not been fully explored yet. This review aims to summarize the potential effects and modulative mechanisms of the gut metabolites on PCOS and suggests its potential intervention targets, thus providing more possible treatment options for PCOS in the future.

Pathogenetic analysis of polycystic ovary syndrome from the perspective of omics

Polycystic ovary syndrome (PCOS) is the most common gynecological endocrine disease, involving multiple genes, multiple pathways, and complex hormone secretion processes. Hence, the pathogenesis of PCOS cannot be explained by a single factor. Omics analysis includes genomics, transcriptomics, and proteomics, which are fast and effective methods for studying the pathogenesis of diseases. PCOS is primarily characterized by androgen excess, and reproductive and metabolic dysfunctions. The application of omics analysis in the body fluids, blood, cells or tissues of women with PCOS offers the potential for unexpected molecular advantages in explaining new mechanisms of PCOS etiology and pathophysiology, and provides new perspectives for identifying potential biomarkers and developing new therapeutic targets. At present, several omics analyses have been applied to produce complex datasets. In this manuscript, the recent advances in omics research on PCOS are summarized, aiming at an important and parallel review of the newly published research.

Polycystic ovary syndrome: Pathways and mechanisms for possible increased susceptibility to COVID-19

In 75% of women with polycystic ovary syndrome (PCOS), insulin action is impaired. In obesity, visceral adipose tissue becomes dysfunctional: Chronic inflammation is favored over storage, contributing to the development of metabolic complications. PCOS, metabolic syndrome (MetSy) and non-alcoholic fatty liver disease (NAFLD) apparently share common pathogenic factors; these include abdominal adiposity, excess body weight and insulin resistance. Alterations in the gut microbiome have been noted in women with PCOS compared to controls; these may lead to deterioration of the intestinal barrier, increased gut mucosal permeability and immune system activation, hyperinsulinemia and glucose intolerance, which hamper normal ovarian function and follicular development (all being hallmarks of PCOS). It has been proposed that PCOS may entail higher susceptibility to coronavirus disease 2019 (COVID-19) via its associated comorbidities (NAFLD, obesity, MetSy and alterations in the gut microbiome). Studies have found an association between acute respiratory distress syndrome (seen in severe cases of COVID-19) and the intestinal microbiome. Furthermore, apparently, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can gain entry to the gastrointestinal tract via locally-expressed angiotensin converting enzyme type 2 receptors. Excess body weight is associated with more severe COVID-19 and increased mortality. Although robust links between SARS-CoV-2 infection and PCOS/NAFLD/gut microbiome/metabolic consequences are yet to be confirmed, it seems that strategies for adapting the intestinal microbiome could help reduce the severity of COVID-19 in women with PCOS with or without NAFLD, MetSy or obesity.

Microbiome and PCOS: State-of-Art and Future Aspects

Polycystic ovary syndrome (PCOS) is a complex and heterogeneous endocrine disease. The hypothesis that alterations in the microbiome are involved in the genesis of PCOS has been postulated. Aim of this review is to summarize the available literature data about the relationship between microbiome and PCOS. A search on PubMed and Medline databases was performed from inception to November 20Most of evidence has focused on the connection of intestinal bacteria with sex hormones and insulin-resistance: while in the first case, a relationship with hyperandrogenism has been described, although it is still unclear, in the second one, chronic low-grade inflammation by activating the immune system, with increased production of proinflammatory cytokines which interfere with insulin receptor function, causing IR (Insulin Resistance)/hyperinsulinemia has been described, as well as the role of gastrointestinal hormones like Ghrelin and peptide YY (PYY), bile acids, interleukin-22 and Bacteroides vulgatus have been highlighted. The lower genital tract microbiome would be affected by changes in PCOS patients too. The therapeutic opportunities include probiotic, prebiotics and synbiotics, as well as fecal microbiota transplantation and the use of IL-22, to date only in animal models, as a possible future drug. Current evidence has shown the involvement of the gut microbiome in PCOS, seen how humanized mice receiving a fecal transplant from women with PCOS develop ovarian dysfunction, immune changes and insulin resistance and how it is capable of disrupting the secondary bile acid biosynthesis. A future therapeutic approach for PCOS may involve the human administration of IL-22 and bile acid glycodeoxycholic acid.