Excessive insulin receptor serine phosphorylation in cultured fibroblasts and in skeletal muscle. A potential mechanism for insulin resistance in the polycystic ovary syndrome

Polycystic ovary syndrome and epithelial-mesenchymal transition: Mendelian randomization and single-cell analysis insights

BACKGROUND

The process of epithelial-mesenchymal transition (EMT) may promote fibrosis in ovarian tissue related to polycystic ovary syndrome (PCOS), thus affecting ovarian function and hormonal balance.

OBJECTIVE

This study aimed to explore key genes associated with EMT in PCOS and their potential molecular regulatory mechanisms, exclusively from the perspective of transcriptomics and single-cell RNA sequencing (scRNA-seq), combined with Mendelian Randomization (MR) analysis.

METHODS

The dataset for PCOS and EMT-related genes (EMT-RGs) were sourced from public databases. The key genes in this study were identified via differential expression analysis, MR, and evaluation of expression levels. Enrichment analysis and a series of functional analyses were conducted on these genes to further elucidate their potential mechanisms. Subsequently, using scRNA-seq data and validation of the expression of key genes, key cell group in PCOS were identified, followed by pseudo-time and cell communication analyses to provide deeper insights.

RESULTS

Three key genes, NUCB2 [odds ratio (OR) = 0.8634, 95% confidence interval (CI): 0.8145-0.9152, P < 0.0001], PGF (OR = 0.8393, 95% CI: 0.7185-0.9805, P < 0.05), and CRIM1 (OR = 0.7539, 95% CI: 0.6556-0.670, P < 0.0001), were identified as having a unidirectional causal association with PCOS and were associated with a reduced risk of PCOS. In public datasets, NUCB2 exhibited significantly increased expression in PCOS samples, while PGF and CRIM1 showed the opposite trends. These three genes were enriched in pathways related to cellular functions, metabolic processes, and the operation of the nervous system, and they were co-expressed in smooth muscle. Additionally, five cell clusters were annotated, among which fibroblasts were identified as key cells due to their highest expression of all three key genes. Further analysis revealed a bifurcation event occurring during the mid-development stage of fibroblasts, with PCOS samples displaying a higher abundance of fibroblasts. In PCOS samples, fibroblasts exhibited more extensive communication with secretory epithelial cells, indicating a more complex intercellular interaction within this condition.

CONCLUSION

This study identified three EMT-RGs: NUCB2, PGF, and CRIM1, which were associated with a reduced risk of PCOS, with fibroblast identified as a key cell group in the disease's pathology. This provides new insights for PCOS research.

Obesity and Polycystic Ovary Syndrome

The core pathophysiology of polycystic ovary syndrome involves an overproduction of androgens primarily originating from ovarian thecal cells. Two major external triggers promote androgen overproduction in the ovaries: the increased secretion of luteinizing hormone, a consequence of aberrant hypothalamic gonadotropin-releasing hormone secretion dynamics, and compensatory hyperinsulinemia resulting from insulin resistance. Obesity interacts with polycystic ovary syndrome in multiple ways, but a major role of obesity in its pathophysiology is the exacerbation of insulin resistance. Additionally, obesity contributes to polycystic ovary syndrome by facilitating the conversion of precursor hormones to testosterone within adipose cells. Moreover, obesity can lead to relative hyperandrogenemia, which is marked by lower levels of sex hormone binding globulin and increased availability of free testosterone to target tissues. Also, obesity affects the secretion of gonadotropins, resulting in heightened luteinizing hormone secretion or increased sensitivity of thecal cells to luteinizing hormone. Obesity-related insulin resistance might be amplified by alterations in adipokine and inflammatory cytokine production. Ultimately, obesity and polycystic ovary syndrome might share a common genetic predisposition. The cornerstone of managing polycystic ovary syndrome is to address individual symptoms such as hyperandrogenism (hirsutism, acne, and female type boldness), menstrual irregularities, and infertility stemming from anovulation. However, obesity is integral to the pathophysiology of polycystic ovary syndrome and exacerbates all of its features. Therefore, lifestyle modifications aimed at weight reduction should be the primary strategy in overweight or obese women with polycystic ovary syndrome.

PCOS - the many faces of a disorder in women and men

PURPOSE

Polycystic ovary syndrome (PCOS) is a very common endocrine, metabolic and reproductive disorder. The underlying pathophysiology is not yet fully understood and both genetic and environmental factors contribute to its development. We aimed to explore clinical and genetic aspects of familial clustering in PCOS, shedding light on its reproductive and metabolic consequences in both male and female first-degree relatives of the affected women.

METHODS

Searching the electronic database of PubMed up to October 2023, we synthesized findings from available prospective and retrospective studies and review articles, investigating the familial clustering of PCOS and incorporating data on its metabolic consequences and genetic associations.

RESULTS

There is a significant clustering of reproductive and metabolic abnormalities in first-degree relatives of women with PCOS. Genetic studies, including genome-wide association studies (GWAS), reveal a complex molecular etiology, emphasizing polygenic architecture. This is supported by the identification of two distinct PCOS subtypes, termed "reproductive" and "metabolic" which exhibit differential genetic underpinnings.

CONCLUSION

Clinicians should be aware of increased reproductive and metabolic dysfunction both in female and male first-degree relatives of PCOS probands. Current challenges include refining genetic risk scores and understanding the impact of PCOS genetic factors on diverse outcomes, necessitating a sex-specific approach in research and clinical practice. Future directions should address causality, improve diagnostic capability, and unravel the long-term consequences in both genders, emphasizing the importance of proactive clinical assessment in PCOS probands and their families.

Role of Omega-3 Fatty Acids in Improving Metabolic Dysfunctions in Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a common endocrine disorder that impacts women of reproductive age. In addition to reproductive and psychological complications, women with PCOS are also at a higher risk of developing metabolic diseases such as obesity, type 2 diabetes and cardiovascular disease. While weight reduction can help manage these complications in overweight or obese women, many weight loss interventions have been ineffective due to weight stigma and its psychological impact on women with PCOS. Therefore, exploring alternative dietary strategies which do not focus on weight loss per se is of importance. In this regard, omega-3 polyunsaturated fatty acids of marine origin (n-3 PUFAs), which are known for their hypotriglyceridemic, cardioprotective and anti-inflammatory effects, have emerged as a potential therapy for prevention and reversal of metabolic complications in PCOS. Several clinical trials showed that n-3 PUFAs can improve components of metabolic syndrome in women with PCOS. In this review, we first summarize the available clinical evidence for different dietary patterns in improving PCOS complications. Next, we summarize the clinical evidence for n-3 PUFAs for alleviating metabolic complications in PCOS. Finally, we explore the mechanisms by which n-3 PUFAs improve the metabolic disorders in PCOS in depth.

The serine phosphorylations in the IRS-1 PIR domain abrogate IRS-1 and IR interaction

Serine phosphorylations on insulin receptor substrate 1 (IRS-1) by diverse kinases aoccur widely during obesity-, stress-, and inflammation-induced conditions in models of insulin resistance and type 2 diabetes. In this study, we define a region within the human IRS-1, which is directly C-terminal to the PTB domain encompassing numerous serine phosphorylation sites including Ser307 (mouse Ser302) and Ser312 (mouse 307) creating a phosphorylation insulin resistance (PIR) domain. We demonstrate that the IRS-1 PTB-PIR with its unphosphorylated serine residues interacts with the insulin receptor (IR) but loses the IR-binding when they are phosphorylated. Surface plasmon resonance studies further confirm that the PTB-PIR binds stronger to IR than just the PTB domain, and that phosphorylations at Ser307, Ser312, Ser315, and Ser323 within the PIR domain result in abrogating the binding. Insulin-responsive cells containing the mutant IRS-1 with all these four serines changed into glutamates to mimic phosphorylations show decreased levels of phosphorylations in IR, IRS-1, and AKT compared to the wild-type IRS-1. Hydrogen-deuterium exchange mass spectrometry experiments indicating the PIR domain interacting with the N-terminal lobe and the hinge regions of the IR kinase domain further suggest the possibility that the IRS-1 PIR domain protects the IR from the PTP1B-mediated dephosphorylation.

Polycystic ovary syndrome

Despite affecting ~11-13% of women globally, polycystic ovary syndrome (PCOS) is a substantially understudied condition. PCOS, possibly extending to men's health, imposes a considerable health and economic burden worldwide. Diagnosis in adults follows the International Evidence-based Guideline for the Assessment and Management of Polycystic Ovary Syndrome, requiring two out of three criteria - clinical or biochemical hyperandrogenism, ovulatory dysfunction, and/or specific ovarian morphological characteristics or elevated anti-Müllerian hormone. However, diagnosing adolescents omits ovarian morphology and anti-Müllerian hormone considerations. PCOS, marked by insulin resistance and hyperandrogenism, strongly contributes to early-onset type 2 diabetes, with increased odds for cardiovascular diseases. Reproduction-related implications include irregular menstrual cycles, anovulatory infertility, heightened risks of pregnancy complications and endometrial cancer. Beyond physiological manifestations, PCOS is associated with anxiety, depression, eating disorders, psychosexual dysfunction and negative body image, collectively contributing to diminished health-related quality of life in patients. Despite its high prevalence persisting into menopause, diagnosing PCOS often involves extended timelines and multiple health-care visits. Treatment remains ad hoc owing to limited understanding of underlying mechanisms, highlighting the need for research delineating the aetiology and pathophysiology of the syndrome. Identifying factors contributing to PCOS will pave the way for personalized medicine approaches. Additionally, exploring novel biomarkers, refining diagnostic criteria and advancing treatment modalities will be crucial in enhancing the precision and efficacy of interventions that will positively impact the lives of patients.

Therapeutic effects and molecular mechanisms of quercetin in gynecological disorders

Quercetin is a representative flavonoid that is widely present in fruits, herbs, and vegetables. It is also an important active core component in traditional Chinese medicines. As an important flavonoid, quercetin has various properties and exerts antioxidant, anti-inflammatory, and cardioprotective effects. The public interest in quercetin is increasing, and quercetin has been used to prevent or treat numerous of diseases, such as polycystic ovary syndrome (PCOS), cancer, autoimmune diseases and chronic cardiovascular diseases, in clinical experiments and animal studies due to its powerful antioxidant properties and minimal side effects. Quercetin exerts marked pharmacological effects on gynecological disorders; however, there have been no reviews about the potential health benefits of quercetin in the context of gynecological disorders, including PCOS, premature ovary failure (POF), endometriosis (EM), ovarian cancer (OC), cervical cancer (CC) and endometrial carcinoma (EC). Thus, this review aimed to summarize the biological effects of quercetin on gynecological disorders and its mechanisms.

Association of Fat Mass and Skeletal Muscle Mass with Cardiometabolic Risk Varied in Distinct PCOS Subtypes: A Propensity Score-Matched Case-Control Study

(1) Background: polycystic ovarian syndrome (PCOS) is a heterogeneous syndrome with a constellation of cardiometabolic risk factors. We aimed to investigate if the association of body fat mass (BFM) and skeletal muscle mass (SMM) with cardiometabolic risk differed in PCOS subtypes. (2) Methods: 401 participants (245 PCOS and 156 controls) were assessed for anthropometric measurements, glucose-lipid profiles, reproductive hormones and body composition with propensity score-matched (PSM) analysis. The association of the cardiometabolic risk score (z score, calculated based on levels of obesity and gluco-lipid measurements) with BFM (estimated by trunk BFM/Height2) and SMM (estimated by SMM/Height2) was calculated. (3) Results: Trunk BFM/Height2 and SMM/Height2 were both positively associated with cardiometabolic risk in PCOS (trunk BFM/Height2, OR 2.33, 95% CI 1.49-3.65; SMM/Height2, OR 2.05, 95% CI 1.12-3.76). SMM/Height2 associated with increased cardiometabolic risk in obese PCOS (BMI ≥ 28 kg/m2, OR 2.27, 95% CI 1.15-4.47). For those with lower BMI (<28 kg/m2), trunk BFM/Height2 showed a higher OR in both groups (PCOS, OR 2.12, 95% CI 1.06-4.24; control 2.04, 95% CI 1.04-4.02). Moreover, distinct associations among BMI-stratified groups were validated in hierarchical clustering identifying metabolic and reproductive clusters. (4) Conclusions: BFM and SMM are synergistically associated with higher cardiometabolic risk in PCOS women. Although BFM contributes to increased cardiometabolic risk, SMM also plays a primary role in obese PCOS. Our results highlight the importance of body composition in the management of PCOS.

Adipose Tissue Dysfunction in Polycystic Ovary Syndrome

PURPOSE

Polycystic ovary syndrome (PCOS) is a complex genetic trait and the most common endocrine disorder of women, clinically evident in 5% to 15% of reproductive-aged women globally, with associated cardiometabolic dysfunction. Adipose tissue (AT) dysfunction appears to play an important role in the pathophysiology of PCOS even in patients who do not have excess adiposity.

METHODS

We undertook a systematic review concerning AT dysfunction in PCOS, and prioritized studies that assessed AT function directly. We also explored therapies that targeted AT dysfunction for the treatment of PCOS.

RESULTS

Various mechanisms of AT dysfunction in PCOS were identified including dysregulation in storage capacity, hypoxia, and hyperplasia; impaired adipogenesis; impaired insulin signaling and glucose transport; dysregulated lipolysis and nonesterified free fatty acids (NEFAs) kinetics; adipokine and cytokine dysregulation and subacute inflammation; epigenetic dysregulation; and mitochondrial dysfunction and endoplasmic reticulum and oxidative stress. Decreased glucose transporter-4 expression and content in adipocytes, leading to decreased insulin-mediated glucose transport in AT, was a consistent abnormality despite no alterations in insulin binding or in IRS/PI3K/Akt signaling. Adiponectin secretion in response to cytokines/chemokines is affected in PCOS compared to controls. Interestingly, epigenetic modulation via DNA methylation and microRNA regulation appears to be important mechanisms underlying AT dysfunction in PCOS.

CONCLUSION

AT dysfunction, more than AT distribution and excess adiposity, contributes to the metabolic and inflammation abnormalities of PCOS. Nonetheless, many studies provided contradictory, unclear, or limited data, highlighting the urgent need for additional research in this important field.

DHT and Insulin Upregulate Secretion of the Soluble Decoy Receptor of IL-33 From Decidualized Endometrial Stromal Cells

Interleukin 33 (IL-33) signaling regulates most of the key processes of pregnancy, including decidualization, trophoblast proliferation and invasion, vascular remodeling, and placental growth. Accordingly, dysregulation of IL-33, its membrane-bound receptor (ST2L, transducer of IL-33 signaling), and its soluble decoy receptor (sST2, inhibitor of IL-33 signaling) has been linked to a wide range of adverse pregnancy outcomes that are common in women with obesity and polycystic ovary syndrome, that is, conditions associated with hyperandrogenism, insulin resistance, and compensatory hyperinsulinemia. To reveal if androgens and insulin might modulate uteroplacental IL-33 signaling, we investigated the effect of dihydrotestosterone (DHT) and/or insulin on the expression of ST2L and sST2 (along with the activity of their promoter regions), IL-33 and sIL1RAP (heterodimerization partner of sST2), during in vitro decidualization of endometrial stromal cells from 9 healthy women. DHT and insulin markedly upregulated sST2 secretion, in addition to the upregulation of its messenger RNA (mRNA) expression, while the proximal ST2 promoter, from which the sST2 transcript originates, was upregulated by insulin, and in a synergistic manner by DHT and insulin combination treatment. On the other hand, sIL1RAP was slightly downregulated by insulin and IL-33 mRNA expression was not affected by any of the hormones, while ST2L mRNA expression and transcription from its promoter region (distal ST2 promoter) could not be detected or showed a negligibly low level. We hypothesize that high levels of androgens and insulin might lead to subfertility and pregnancy complications, at least partially, through the sST2-dependent downregulation of uteroplacental IL-33 signaling.

Lean mass and associated factors in women with PCOS with different phenotypes

Although current evidence suggests increased risk of obesity, insulin resistance, and metabolic alterations in patients with polycystic ovary syndrome (PCOS), especially of a hyperandrogenic phenotype, the impact of each one of these variables on muscle mass remains uncertain. In this case-control study, we evaluated clinical and hormonal characteristics related to lean body mass according to the different PCOS phenotypes. We performed clinical, metabolic, and hormonal assessments and evaluated body compartments by dual-energy X-ray absorptiometry in 133 women of reproductive age. Creatinine served as an indirect marker of lean mass. Median age was 28 (range, 17-37) years. Women with phenotypes A and B (n = 59) had higher body mass index (BMI) and metabolic syndrome prevalence than those with phenotype C (n = 23) and controls (n = 51) (p<0.005). Women with phenotypes A and B also had higher Ferriman-Gallwey score (p<0.001), insulin levels (p = 0.006), HOMA-IR (p = 0.008), testosterone (p = 0.008), free androgen index (FAI) (p<0.001), fat mass index (FMI) (p = 0.015), android-to-gynoid fat ratio (p = 0.036), and bone mineral density (BMD) at lumbar spine (p = 0.027) and total femur (p = 0.013) than controls. Median appendicular lean mass index (ALMI) was higher in phenotypes A and B than in controls (7.01 [IQR, 6.33-8.02] vs. 6.69 [IQR, 5.94-7.09], p = 0.024), but it did not differ significantly from that in phenotype C (6.60 [IQR, 6.16-7.22], p = 0.222). Even after adjusting for BMI, ALMI correlated positively with creatinine in women with phenotypes A and B (rho = 0.319, p = 0.023) but not in those with phenotype C (p = 0.238) or controls (p = 0.097). In multivariate linear regression analyses, ALMI was positively associated with insulin, FAI, FMI, and total femur BMD. The present results suggest that fasting insulin, FAI, fat mass, and total femur BMD were positively associated with increased lean mass in women with PCOS phenotypes A and B.

Mechanism and recent updates on insulin-related disorders

Insulin, a small protein with 51 amino acids synthesized by pancreatic β-cells, is crucial to sustain glucose homeostasis at biochemical and molecular levels. Numerous metabolic dysfunctions are related to insulin-mediated altered glucose homeostasis. One of the significant pathophysiological conditions linked to the insulin associated disorder is diabetes mellitus (DM) (type 1, type 2, and gestational). Insulin resistance (IR) is one of the major underlying causes of metabolic disorders despite its association with several physiological conditions. Metabolic syndrome (MS) is another pathophysiological condition that is associated with IR, hypertension, and obesity. Further, several other pathophysiological disorders/diseases are associated with the insulin malfunctioning, which include polycystic ovary syndrome, neuronal disorders, and cancer. Insulinomas are an uncommon type of pancreatic β-cell-derived neuroendocrine tumor that makes up 2% of all pancreatic neoplasms. Literature revealed that different biochemical events, molecular signaling pathways, microRNAs, and microbiota act as connecting links between insulin disorder and associated pathophysiology such as DM, insuloma, neurological disorder, MS, and cancer. In this review, we focus on the insulin-related disorders and the underlying mechanisms associated with the pathophysiology.

Pathophysiology and Nutritional Approaches in Polycystic Ovary Syndrome (PCOS): A Comprehensive Review

PURPOSE OF REVIEW

Polycystic ovary syndrome (PCOS) is the most common endocrine and metabolic disorder in women of reproductive age worldwide. This disease causes menstrual, metabolic, and biochemical abnormalities such as hyperandrogenism, oligo-anovulatory menstrual cycles, polycystic ovary, hyperleptinemia, insulin resistance (IR), and cardiometabolic disorders, often associated with overweight or obesity and visceral adiposity.

RECENT FINDINGS

The etiology and pathophysiology of PCOS are not yet fully understood, but insulin seems to play a key role in this disease. PCOS shares an inflammatory state with other chronic diseases such as obesity, type II diabetes, and cardiovascular diseases; however, recent studies have shown that a healthy nutritional approach can improve IR and metabolic and reproductive functions, representing a valid therapeutic strategy to ameliorate PCOS symptomatology. This review aimed to summarize and collect evidence about different nutritional approaches such as the Mediterranean diet (MedDiet) and the ketogenic diet (KD), as well as bariatric surgery and nutraceutical supplementation as probiotics, prebiotics, and synbiotics, among the others, used in patients with PCOS.

Diabetes detection in women with gestational diabetes and polycystic ovarian syndrome

Gestational diabetes mellitus (GDM) and polycystic ovarian syndrome (PCOS) represent two of the highest risk factors for development of type 2 diabetes mellitus in young women. As these increasingly common conditions generally affect younger women, early detection of dysglycemia is key if preventative measures are to be effective. While international guidance recommends screening for type 2 diabetes, current screening strategies suffer from significant challenges.First, guidance lacks consensus in defining which tests to use and frequency of monitoring, thereby sending mixed messages to healthcare professionals.Second, conformity to guidance is poor, with only a minority of women having tests at the recommended frequency (where specified). Approaches to improve conformity have focused on healthcare related factors (largely technology driven reminder systems), but patient factors such as convenience and clear messaging around risk have been neglected.Third, and most critically, current screening strategies are too generic and rely on tests that become abnormal far too late in the trajectory towards dysglycemia to offer opportunities for effective preventative measures. Risk factors show wide interindividual variation, and insulin sensitivity and β cell function are often abnormal during pre-diabetes stage, well before frank diabetes.New, consistent, targeted screening strategies are required that incorporate early, prevention focused testing and personalised risk stratification.

Insulin Resistance and Bone Metabolism Markers in Women with Polycystic Ovary Syndrome: A Cross-Sectional Study on Females from the Islamic University Medical Center

Background and Objectives: polycystic ovarian syndrome (PCOS) prevails in females in the 18-40-year-old age group and varies from 5-20% depending on the demographic and diagnostic standards. It is unknown how long passes between the onset of a specific symptom and the appearance of the disease. The three most significant characteristics of PCOS include irregular menstruation, a polycystic ovarian shape found by pelvic ultrasound, and hyperandrogenism, which could possibly delay menarche. This study's objective was to assess insulin resistance and bone bio-markers' metabolism-involved characteristics of females with PCOS. Materials and Methods: We present a cross-sectional study carried out on 100 female patients suffering from PCOS and 100 healthy female subjects as a control living in Saudi Arabia in the Al-Madinah Al-Munawara Region between May 2021 and March 2022. The age of the studied groups ranges from 20-40 years, and patients were categorized into three groups; group I (control, n = 100), group IIa (overweight or obese females with PCOS, n = 70), and group IIb (non-obese females with PCOS, n = 30). The diagnosis of PCOS was carried out as per Rotterdam criteria as recommended for adolescent and adult subjects. All the groups were subjected to physical examination, and anthropometric measures, biochemical parameters, endocrine activity, and clinical parameters were determined. The data obtained were computerized and analyzed statistically using the SPSS program for range, mean, and standard deviation. ANOVA test with post hoc Tukey test was applied to assess the pattern and variation among the test and control groups. Results: In the present study, age, waist circumstances, systolic blood pressure, and diastolic blood pressure were reported enhanced in the PCOS over the control group. Additionally, anthropometric measures were reported slightly upregulated in group IIa over group IIb (p < 0.001). Biochemical parameters including glucose, insulin incidence, and lipids were reported higher in the PCOS over the control group, where group IIa showed slightly increased values compared to group IIb (p < 0.001). On the contrary, PTH, Ca+2, and 25(OH)D levels were reported lower in the PCOS over the control group. However, in the control groups, a slight variation was reported as higher in group IIa compared to group II. In the study, PTH and 25(OH)D were found associated with bone metabolism; a lower level of PTH and 25 (OH) D is linked with a decline in bone density. Conclusions: Lower serum levels of PINP and osteocalcin along with the 25(OH)D were associated with the PCOS compared to the control group, imposing a higher risk of the syndrome. On the contrary, an elevated level of NTx in groups IIa and IIb over the control group was associated with insulin resistance and bone metabolism.

Molecular characterization of extracellular vesicles derived from follicular fluid of women with and without PCOS: integrating analysis of differential miRNAs and proteins reveals vital molecules involving in PCOS

PURPOSE

To elucidate the characterization of extracellular vesicles (EVs) in the follicular fluid-derived extracellular vesicles (FF-EVs) and discover critical molecules and signaling pathways associating with the etiology and pathobiology of PCOS, the differentially expressed miRNAs (DEmiRNAs) and differentially expressed proteins profiles (DEPs) were initially explored and combinedly analyzed.

METHODS

First, the miRNA and protein expression profiles of FF-EVs in PCOS patients and control patients were compared by RNA-sequencing and tandem mass tagging (TMT) proteomic methods. Subsequently, Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes were used to analyze the biological function of target genes of DEmiRNAs and DEPs. Finally, to discover the functional miRNA-target gene-protein interaction pairs involved in PCOS, DEmiRs target gene datasets and DEPs datasets were used integratedly.

RESULTS

A total of 6 DEmiRNAs and 32 DEPs were identified in FF-EVs in patients with PCOS. Bioinformatics analysis revealed that DEmiRNAs target genes are mainly involved in thiamine metabolism, insulin secretion, GnRH, and Apelin signaling pathway, which are closely related to the occurrence of PCOS. DEPs also closely related to hormone metabolism processes such as steroid hormone biosynthesis. In the analysis integrating DEmiRNAs target genes and DEPs, two molecules, GRAMD1B and STPLC2, attracted our attention that are closely associated with cholesterol transport and ceramide biosynthesis, respectively.

CONCLUSION

Dysregulated miRNAs and proteins in FF-EVs, mainly involving in hormone metabolism, insulin secretion, neurotransmitters regulation, adipokine expression, and secretion, may be closely related to PCOS. The effects of GRAMD1B and STPLC2 on PCOS deserve further study.

The polycystic ovary syndrome: the first 150 years of study

The communities of reproductive medicine and reproductive sciences have been witness to an enormous acceleration of interest in polycystic ovary syndrome (PCO) since the mid-19th century. Although progress has been increasingly palpable, the fundamentals of the etiology and pathophysiology of PCO remain as elusive as ever. Particularly lacking is a requisite understanding of events at the cellular and molecular levels. As we cross the millennial divide, it appears appropriate that an interim progress report be crafted. This treatise is attempting to meet this objective. What follows traces the chronology of the recorded history of PCO in 4 parts.

Insulin Metabolism in Polycystic Ovary Syndrome: Secretion, Signaling, and Clearance

Polycystic ovary syndrome (PCOS) is the most common endocrine and metabolic disorder in women of reproductive age. Its heterogeneous clinical presentation is characterized by hyperandrogenemia, reproductive changes, polycystic ovary morphology, and insulin resistance (IR). The primary pathophysiological process in its multifactorial etiology has not yet been identified. However, the two most proposed core etiologies are the disruption of insulin metabolism and hyperandrogenemia, both of which begin to intertwine and propagate each other in the later stages of the disease. Insulin metabolism can be viewed as the interconnectedness of beta cell function, IR or insulin sensitivity, and insulin clearance. Previous studies of insulin metabolism in PCOS patients have yielded conflicting results, and literature reviews have focused mainly on the molecular mechanisms and clinical implications of IR. In this narrative review, we comprehensively explored the role of insulin secretion, clearance, and decreased sensitivity in target cells as a potential primary insult in PCOS pathogenesis, along with the molecular mechanism behind IR in PCOS.

Female infertility in the era of obesity: The clash of two pandemics or inevitable consequence?

Obesity is an epidemic that has led to a rise in the incidence of many comorbidities: among others, reduced fertility is often under-evaluated in clinical practice. The mechanisms underlying the link between reduced fertility and obesity are numerous, with insulin resistance, hyperglycaemia and the frequent coexistence of polycystic ovary syndrome being the most acknowledged. However, several other factors concur, such as gut microbiome alterations, low-grade chronic inflammation and oxidative stress. Not only do women with obesity take longer to conceive, but in vitro fertilization (IVF) is also less likely to succeed. We herein provide an updated state-of-the-art regarding the molecular bases of what we could define as dysmetabolic infertility, focusing on the clinical aspects, as well as possible treatment.

Deconstructing a Syndrome: Genomic Insights Into PCOS Causal Mechanisms and Classification

Polycystic ovary syndrome (PCOS) is among the most common disorders in women of reproductive age, affecting up to 15% worldwide, depending on the diagnostic criteria. PCOS is characterized by a constellation of interrelated reproductive abnormalities, including disordered gonadotropin secretion, increased androgen production, chronic anovulation, and polycystic ovarian morphology. It is frequently associated with insulin resistance and obesity. These reproductive and metabolic derangements cause major morbidities across the lifespan, including anovulatory infertility and type 2 diabetes (T2D). Despite decades of investigative effort, the etiology of PCOS remains unknown. Familial clustering of PCOS cases has indicated a genetic contribution to PCOS. There are rare Mendelian forms of PCOS associated with extreme phenotypes, but PCOS typically follows a non-Mendelian pattern of inheritance consistent with a complex genetic architecture, analogous to T2D and obesity, that reflects the interaction of susceptibility genes and environmental factors. Genomic studies of PCOS have provided important insights into disease pathways and have indicated that current diagnostic criteria do not capture underlying differences in biology associated with different forms of PCOS. We provide a state-of-the-science review of genetic analyses of PCOS, including an overview of genomic methodologies aimed at a general audience of non-geneticists and clinicians. Applications in PCOS will be discussed, including strengths and limitations of each study. The contributions of environmental factors, including developmental origins, will be reviewed. Insights into the pathogenesis and genetic architecture of PCOS will be summarized. Future directions for PCOS genetic studies will be outlined.

Key signalling pathways underlying the aetiology of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common endocrine condition characterised by a range of reproductive, endocrine, metabolic and psychological abnormalities. Reports estimate that around 10% of women of reproductive age are affected by PCOS, representing a significant prevalence worldwide, which poses a high economic health burden. As the origin of PCOS remains largely unknown, there is neither a cure nor mechanism-based treatments leaving patient management suboptimal and focused solely on symptomatic treatment. However, if the underlying mechanisms underpinning the development of PCOS were uncovered then this would pave the way for the development of new interventions for PCOS. Recently, there have been significant advances in our understanding of the underlying pathways likely involved in PCOS pathogenesis. Key insights include the potential involvement of androgens, insulin, anti-Müllerian hormone and transforming growth factor beta in the development of PCOS. This review will summarise the significant scientific discoveries on these factors that have enhanced our knowledge of the mechanisms involved in the development of PCOS and discuss the impact these insights may have in shaping the future development of effective strategies for women with PCOS.

Efficacy of Myo-inositol on Anthropometric, Metabolic, and Endocrine Outcomes in PCOS Patients: a Meta-analysis of Randomized Controlled Trial

Polycystic ovary syndrome (PCOS) is a common cause of female infertility, affecting 5-10% of women of reproductive age. Many studies have reported improvement in insulin resistance and thereby intracellular glucose uptake after myo-inositol treatment in PCOS patients, but these studies have a small sample size, varying methodology, and outcome analysis. Therefore, we designed a present meta-analysis of randomized controlled trials to explore the effect of myo-inositol supplementation on anthropometric, metabolic, and endocrine outcomes in PCOS patients. Randomized controlled trials assessing the effectiveness of myo-inositol were identified in electronic databases like PubMed, Cochrane, Embase, MEDLINE, CINAHL, and AMED. Listed references and citations of related articles were also screened manually to identify additional studies. Research papers for which full-text copies were not available on scientific databases were procured from respective authors. Thereafter, data were extracted from included studies and analyzed using RevMan 5.3 of the Cochrane Collaboration. A total of 17 randomized controlled trials with 1083 PCOS patients were included in this meta-analysis. Among the 17 trials, 7 trials compared myo-inositol with folic acid, 8 trials compared myo-inositol with metformin, and 2 trials compared myo-inositol with oral contraceptives. No significant improvement in body mass index, waist-to-hip ratio, fasting insulin, fasting glucose, HOMA, LH, FSH, estradiol, sex hormone-binding globulin, dehydroepiandrosterone, and total testosterone levels were observed after myo-inositol treatment in PCOS patients except androstenedione and prolactin levels. Clinically significant improvement was not observed in anthropometric, metabolic, and endocrine outcomes after myo-inositol treatment in PCOS patients. However, heterogeneity between studies was high.

Effects of Different Ovulation Induction Regimens on Sex Hormone Levels and Serum CTRP3 and CTRP15 Levels in Patients with Polycystic Ovary Syndrome (PCOS)

Objective

A retrospective cohort study aimed to explore the effects of different ovulation induction regimens on the levels of sex hormones and serum C1q/TNF-related protein-3 (CTRP3) and C1q/TNF-related protein-15 (CTRP15) in patients with PCOS.

Methods

A total of 100 patients with PCOS treated in the department of gynecology and obstetrics from February 2019 to April 2021 in our hospital were enrolled. The patients were arbitrarily assigned into control group and study group. The treatment effect, pregnancy rate, ovulation rate, follicle size, thickness of endometrium, number of mature follicles and ovulation, serum levels of follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), testosterone (T), serum CTRP3, CTRP15 and menstrual score were compared.

Results

There exhibited no statistical difference in baseline clinical data between the two kinds of patients. The therapeutic effects were compared, the effective rate was 98.00% in the study group, 13 cases in the control group, 20 cases in the effective group and 7 cases in the control group, and the effective rate was 86.00%. The effective rate in the study group was higher (P <0.05). The size of follicles and the thickness of endometrium in the two groups were compared before and after intervention. There exhibited no significant difference in the size of follicles and the thickness of endometrium before and after intervention (P >0.05). The size of follicles and the thickness of endometrium in the study group were significantly higher (P <0.05). The size of follicles and the thickness of endometrium in the study group were significantly higher (P <0.05). There exhibited no significant difference in the number of mature follicles and ovulation before and after intervention (P >0.05). After intervention, the number of mature follicles and ovulation in the two groups increased. The number of mature follicles and ovulation in the study group were (4.76 ± 0.90) and (4.48 ± 0.73), respectively, which were higher compared to the control group (2.45 ± 0.86) and (2.82 ± 0.84), respectively (P <0.05). The levels of serum LH, FSH, E2 and T were not significantly different before and after intervention. After the intervention of different ways of ovulation induction, the levels of serum LH, FSH, E2 and T in the two groups continued to decrease, and the levels of the above sex hormones in the study group were significantly lower (P <0.05). The menstrual score and the levels of serum CTRP3 and CTRP15 were compared before and after intervention. After intervention, the menstrual score of patients in both groups decreased, and the menstrual score of the study group was lower. In addition, the levels of serum CTRP3 and CTRP15 in the two groups decreased after intervention. Compared with the control group, the levels of CTRP3 and CTRP15 in the study group were lower after intervention (P <0.05). The ovulation rate and pregnancy rate of the two groups were compared. In the study group, there were 45 ovulation cases, the ovulation rate was 90.00% (45/50), the pregnancy rate was 33 cases, the pregnancy rate was 66.00% (33/50), and the ovulation rate in the control group was 31 cases, the ovulation rate was 62.00% (31/50), the pregnancy rate was 20 cases, and the pregnancy rate was 40.00% (20/50). The ovulation rate and pregnancy rate in the study group were higher (P <0.05).

Conclusion

Different ovulation induction regimens have different effects on the levels of sex hormones and serum CTRP3 and CTRP15 in patients with PCOS. Long-acting follicular phase regimens can effectively promote the therapeutic effect of patients and increase the ovulation rate and pregnancy rate. In addition, it can also reduce the levels of serum LH, follicle stimulating FSH, E2 and testosterone T, and help to promote the levels of serum CTRP3 and CTRP15, which is worth popularizing and applying in clinic.

Characterizing skeletal muscle dysfunction in women with polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is the most common endocrine condition affecting women. It has traditionally been viewed as a primarily reproductive disorder; however, it is increasingly recognized as a lifelong metabolic disease. Women with PCOS are at increased risk of insulin resistance (IR), type 2 diabetes mellitus, non-alcoholic fatty liver disease and cardiovascular disease. Although not currently a diagnostic criterion, IR is a cardinal pathophysiological feature and highly prevalent in women with PCOS. Androgens play a bidirectional role in the pathogenesis of IR, and there is a complex interplay between IR and androgen excess in women with PCOS. Skeletal muscle has a key role in maintaining metabolic homeostasis and is also a metabolic target organ of androgen action. Skeletal muscle is the organ responsible for the majority of insulin-mediated glucose disposal. There is growing interest in the relationship between skeletal muscle, androgen excess and mitochondrial dysfunction in the pathogenesis of metabolic disease in PCOS. Molecular mechanisms underpinning defects in skeletal muscle dysfunction in PCOS remain to be elucidated, but may represent promising targets for future therapeutic intervention. In this review, we aim to explore the role of skeletal muscle in metabolism, focusing particularly on perturbations in skeletal muscle specific to PCOS as observed in recent molecular and in vivo human studies. We review the possible role of androgens in the pathophysiology of skeletal muscle abnormalities in PCOS, and identify knowledge gaps, areas for future research and potential therapeutic implications. Despite increasing interest in the area of skeletal muscle dysfunction in women with PCOS, significant challenges and unanswered questions remain, and going forward, novel innovative approaches will be required to dissect the underlying mechanisms.

Current Perspectives on Nonalcoholic Fatty Liver Disease in Women with Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is one of the most common reproductive, endocrine, and metabolic disorders in premenopausal women. Clinically, PCOS is mainly caused by androgen excess and ovarian dysfunction, manifested by anovulatory menstrual cycles, infertility, and hirsutism. In addition, PCOS increases the risk of insulin resistance, obesity, cardiovascular disease, anxiety and depression, dyslipidemia, and endometrial cancer. Nonalcoholic fatty liver disease (NAFLD) is defined as ≥5% fat accumulation in the liver in the absence of remaining secondary causes and has become one of the most common chronic liver diseases worldwide. The prevalence of NAFLD is significantly higher and more severe in women with PCOS, and its pathogenesis can be associated with various risk factors such as hyperandrogenemia, insulin resistance, obesity, chronic low-grade inflammation, and genetic factors. Although there is no definitive solution for the management of NAFLD in PCOS, some progress has been made. Lifestyle modification should be the basis of management, and drugs to improve metabolism, such as insulin sensitizers and glucagon-like peptide-1 agonists, may show better efficacy. Bariatric surgery may also be a treatment of NAFLD in obese women with PCOS. This paper reviews three aspects of prevalence, risk factors, and management, in order to better understand the current state of research on NAFLD in PCOS, to explore the pathogenesis of NAFLD in PCOS, and to encourage further research on the application of drugs in this field.

A Review of Special Considerations on Insulin Resistance Induced Hyperandrogenemia in Women with Polycystic Ovary Syndrome: A Prominent COVID-19 Risk Factor

Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-CoV-2) infecting mechanism depends on hosting angiotensin-converting enzyme 2 (ACE2) and transmembrane protease serine 2 (TMPRSS2) as essential components and androgens as regulators for inducing the expression of these components. Therefore, hyperandrogenism-related disease such as polycystic ovary syndrome (PCOS) in insulin resistant women in reproductive-age is a high-risk factor for SARS-CoV-2 infection. Here, we describe the signaling pathways that might increase the susceptibility and severity of this new pandemic in PCOS women with insulin resistance (IR). Luteinizing hormone and insulin increase the risk of SARS-CoV-2 infection in these patients via the induction of steroidogenic enzymes expression through cAMP-response element binding protein and Forkhead box protein O1 (FOXO1), respectively. TMPRSS2 expression is activated through phosphorylation of FOXO1 in ovaries. In other words, SARS-CoV-2 infection is associated with temporary IR by affecting ACE2 and disturbing β-pancreatic function. Therefore, PCOS, IR, and SARS-CoV-2 infection are three corners of the triangle that have complicated relations, and their association might increase the risk of SARS-CoV-2 infection and severity.

PCOS and Assisted Reproduction Technique: Role and Relevance of Inositols

Polycystic ovary syndrome is an endocrine disorder often characterized by insulin resistance and hyperinsulinemia, especially in overweight/obese women. Among insulin sensitizers, the positive role of inositols has been increasingly established in recent years. The action of inositols not only concerns the metabolic parameters of these patients, but also the hormonal profile, resulting in beneficial effects on ovarian function. For this reason, many studies have tried to recognize their role in PCOS infertile women who underwent in vitro fertilization (IVF) procedures.

Metformin does not improve insulin sensitivity over hypocaloric diets in women with polycystic ovary syndrome: a systematic review of 12 studies

OBJECTIVE

To improve insulin action, most clinicians prescribe Metformin in patients with insulin resistance (IR). Women with polycystic ovary syndrome (PCOS), in which IR is an important physiopathological mechanism, treatment with Metformin and specialized diets have been suggested to reduce the patient's IR. However, numerous studies have demonstrated conflicting results with respect to supplementing a diet with Metformin. Therefore, we conducted a meta-analysis to determine if Metformin provides a benefit in conjunction with hypocaloric diets to improve insulin sensitivity in PCOS women.

METHODS

PubMed, SCOPUS, LILACS, and EBSCO databases and retrieved studies' bibliographies were searched for prospective studies that investigated the effect between Metformin and hypocaloric diets in PCOS women until April 2020. Pre- and post-intervention values for fasting plasma glucose (FPG), fasting plasma insulin (FPI), and IR indices (HOMA1-IR, ISI, and QUICKI) were extracted. Using Comprehensive Meta-Analysis software, the pooled standard difference in the means (SDM) and 95%CIs were calculated.

RESULTS

11 publications (12 studies) were selected. There was not a benefit of adding Metformin to a hypocaloric diet with respect to FPG (SDM= -0.17; 95%CI: -0.48-0.14, p = .28) and FPI (SDM = 0.16; 95%CI: -0.24-0.55, p = .45). None of the IR indices also demonstrated any benefit of using Metformin when a diet intervention was implemented (HOMA1-IR: SDM = 0.28; 95%CI: -0.27-0.84, p = .315; ISI: SDM = 0.344; 95%CI: -0.17-0.85, p = .186; QUICKI: SDM= -0.01; 95%CI: -0.42-0.41, p = .968).

CONCLUSION

Here, we determined that adding Metformin to hypocaloric diets did not improve serum glucose or insulin concentrations as well as IR in PCOS women.

The role of polymorphism in various potential genes on polycystic ovary syndrome susceptibility and pathogenesis

Polycystic ovary syndrome (PCOS) is the most common endocrinopathies affecting the early reproductive age in women, whose pathophysiology perplexes many researchers till today. This syndrome is classically categorized by hyperandrogenism and/or hyperandrogenemia, menstrual and ovulatory dysfunction, bulky multi follicular ovaries on Ultrasonography (USG), and metabolic abnormalities such as hyperinsulinemia, dyslipidemia, obesity. The etiopathogenesis of PCOS is not fully elucidated, but it seems that the hypothalamus-pituitary-ovarian axis, ovarian, and/or adrenal androgen secretion may contribute to developing the syndrome. Infertility and poor reproductive health in women's lives are highly associated with elevated levels of androgens. Studies with ovarian theca cells taken from PCOS women have demonstrated increased androgen production due to augmented ovarian steroidogenesis attributed to mainly altered expression of critical enzymes (Cytochrome P450 enzymes: CYP17, CYP21, CYP19, CYP11A) in the steroid hormone biosynthesis pathway. Despite the heterogeneity of PCOS, candidate gene studies are the widely used technique to delineate the genetic variants and analyze for the correlation of androgen biosynthesis pathway and those affecting the secretion or action of insulin with PCOS etiology. Linkage and association studies have predicted the relationship between genetic variants and PCOS risk among families or populations. Several genes have been proposed as playing a role in the etiopathogenesis of PCOS, and the presence of mutations and/or polymorphisms has been discovered, which suggests that PCOS has a vital heritable component. The following review summarizes the influence of polymorphisms in crucial genes of the steroidogenesis pathway leading to intraovarian hyperandrogenism which can result in PCOS.

Polycystic Ovary Syndrome in Insulin-Resistant Adolescents with Obesity: The Role of Nutrition Therapy and Food Supplements as a Strategy to Protect Fertility

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in young reproductive-aged women. PCOS is often associated with obesity and impairs reproductive health. Even though several theories have been proposed to explain the pathogenic mechanism of PCOS, the role of insulin resistance (IR) as a key etiological component, independently of (but amplified by) obesity, is well recognized. The consequent hyperinsulinemia activates excessive ovarian androgen production, leading to PCOS. Additionally, the state of chronic inflammation related to obesity impacts ovarian physiology due to insulin sensitivity impairment. The first-line treatment for adolescents with obesity and PCOS includes lifestyle changes; personalized dietary interventions; and, when needed, weight loss. Medical nutrition therapy (MNT) and the use of specific food supplements in these patients aim at improving symptoms and signs, including insulin resistance and metabolic and reproductive functions. The purpose of this narrative review is to present and discuss PCOS in adolescents with obesity, its relationship with IR and the role of MNT and food supplements in treatment. Appropriate early dietary intervention for the management of adolescents with obesity and PCOS should be considered as the recommended approach to restore ovulation and to protect fertility.

Role of insulin and insulin resistance in androgen excess disorders

Insulin has complex effects on cell growth, metabolism and differentiation, and these effects are mediated by a cell-surface bound receptor and eventually a cascade of intracellular signaling events. Among the several metabolic and growth-promoting effects of insulin, insulin resistance is defined as an attenuated effect of insulin on glucose metabolism, primarily the limited export of blood glucose into skeletal muscle and adipose tissue. On the other hand, not all the signaling pathways and insulin-responsive tissues are equally affected, and some effects other than the metabolic actions of insulin are overexpressed. Ovaries and the adrenal glands are two examples of tissues remaining sensitive to insulin actions where insulin may contribute to increased androgen secretion. Polycystic ovary syndrome (PCOS) is the most common form of androgen excess disorder (AED), and its pathogenesis is closely associated with insulin resistance. Patients with idiopathic hirsutism also exhibit insulin resistance, albeit lower than patients with PCOS. Although it is not as evident as in PCOS, patients with congenital adrenal hyperplasia may have insulin resistance, which may be further exacerbated with glucocorticoid overtreatment and obesity. Among patients with severe insulin resistance syndromes, irrespective of the type of disease, hyperinsulinemia promotes ovarian androgen synthesis independently of gonadotropins. It is highly debated in whom and how insulin resistance should be diagnosed and treated among patients with AEDs, including PCOS. It is not suitable to administer an insulin sensitizer relying on only some mathematical models used for estimating insulin resistance. Instead, the treatment decision should be based on the constellation of the signs, symptoms and presence of obesity; acanthosis nigricans; and some laboratory abnormalities such as impaired glucose tolerance and impaired fasting glucose.

Defining the underlying defect in insulin action in type 2 diabetes

Insulin resistance is one of the earliest defects in the pathogenesis of type 2 diabetes. Over the past 50 years, elucidation of the insulin signalling network has provided important mechanistic insights into the abnormalities of glucose, lipid and protein metabolism that underlie insulin resistance. In classical target tissues (liver, muscle and adipose tissue), insulin binding to its receptor initiates a broad signalling cascade mediated by changes in phosphorylation, gene expression and vesicular trafficking that result in increased nutrient utilisation and storage, and suppression of catabolic processes. Insulin receptors are also expressed in non-classical targets, such as the brain and endothelial cells, where it helps regulate appetite, energy expenditure, reproductive hormones, mood/behaviour and vascular function. Recent progress in cell biology and unbiased molecular profiling by mass spectrometry and DNA/RNA-sequencing has provided a unique opportunity to dissect the determinants of insulin resistance in type 2 diabetes and the metabolic syndrome; best studied are extrinsic factors, such as circulating lipids, amino acids and other metabolites and exosomal microRNAs. More challenging has been defining the cell-intrinsic factors programmed by genetics and epigenetics that underlie insulin resistance. In this regard, studies using human induced pluripotent stem cells and tissues point to cell-autonomous alterations in signalling super-networks, involving changes in phosphorylation and gene expression both inside and outside the canonical insulin signalling pathway. Understanding how these multi-layered molecular networks modulate insulin action and metabolism in different tissues will open new avenues for therapy and prevention of type 2 diabetes and its associated pathologies.

Nutritional guidelines for the management of insulin resistance

Obesity and its related co-morbidities, namely type 2 diabetes (T2D), pose a significant global public health problem. Insulin resistance (IR) in muscle and liver is the core pathophysiologic defect that underlies obesity preceding and predicting the onset of T2D in susceptible humans. There is a broad population with IR that has no indication for prescription of medications, who still need medical consultation and specific advice in this respect. This prevalent need can be achieved by appropriate diet, exercise, and other behavioral therapies for lifestyle interventions. Despite a well-recognized role of IR in the progression to metabolic diseases, no specific nutritional recommendations exist to manage this condition, to the best of our knowledge. An international panel of experts reviewed and critically appraised the updated literature published about this topic. This review primarily examines the evidence for areas of consensus and ongoing uncertainty or controversy about diet and exercise approaches for IR. The aim of this article is to present the most common IR states, namely obesity and Polycystic Ovary Syndrome (PCOS), and provide nutritional advice to manage IR, hyperinsulinemia, and reactive hypoglycemia. These nutritional guidelines could prevent progression or worsening of IR with resultant beta-cell failure and, as a result, T2D.

Assessment of Early Markers of Cardiovascular Risk in Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a heterogeneous syndrome, with long-term sequelae from birth to senescence. The long-term effects of PCOS are attributed to several metabolic aberrations ensuing the syndrome. In a systematic review of literature regarding the cardiovascular risk factors that accompany PCOS, we found that macrovascular function has been assessed by flow-mediated dilatation (FMD), microvascular function by venous occlusion plethysmography (VOP), and arterial structure by ultrasonographic assessment of intima-media thickness (IMT) usually of the carotid artery. Contradictory results have been reported; however, in most studies, endothelial dysfunction, an early marker of atherosclerosis assessed either by haemodynamic methods such as FMD or by biochemical methods such as endothelin-1 levels, was found to be impaired. VOP is a less-studied method, with few indices altered. IMT was found to be altered in most of the included studies, but the population was more heterogeneous. Inflammatory markers, including C-reactive protein, were also found to be altered in most studies. On the other hand, a number of interventions have been shown beneficial for the markers of cardiovascular risk, in the context of insulin-sensitizers. However, other interventions such as oral contraceptive pills or statins did not consistently show a similar beneficial effect. In summary, the early identification and eventual treatment of cardiovascular clinical and biochemical risk factors may be used in clinical practice to prevent potential 'silent' triggers of cardiovascular disease.

A review on inositol's potential in cyclic disturbances of adipose-endocrinology-associated polycystic ovary syndrome

Since the lack of certainty in identifying polycystic ovary syndrome (PCOS) demonstrates confusion regarding the disorder's pathophysiology and its therapeutic approaches, systematic screening of women under diagnostic guidelines of the NIH reported that about 4-10 percent of reproductive women aged 20-44 years suffer from PCOS. Not all females with PCOS-defining biochemical and clinical characteristics and about 22% of PCOS women have no symptoms. PCOS is a heterogeneous phenotypic and clinical condition, combined with metabolic implications. The root cause of PCOS is the major issue of IR or irregular androgen secretion and constant effort is being made in identifying the dynamic pathogenic network underlying the syndrome. Regardless of PCOS initiating cause, IR therapy and hyperinsulinemia can restore metabolic and hormonal homeostasis, and minimize ovarian dysfunction. Thus, the impact of insulin on ovaries in hyperinsulinemic individuals can account for many of the PCOS characteristics and is important for developing treatment strategies. Therefore, our primary aim is to investigate the proper understanding of endocrine disruption during PCOS and secondary to the therapeutic potential of inositol in reestablishing the equilibrium of ovarian dysfunction, anovulation, and eventually infertility.

Insulin resistance and PCOS: chicken or egg?

PCOS is a common and heterogeneous endocrine disorder in women of reproductive age, frequently associated with metabolic abnormalities. It was estimated that about 75% of these subjects have an impairment of insulin action, as measured by gold standard methods. While the relationship between insulin resistance and PCOS is consistently shown by a number of studies, the mechanisms underlying its primary origin still remains an unsolved issue. Insulin resistance and the associated hyperinsulinemia can induce both the endocrine and reproductive traits of PCOS. However, androgen excess, in turn, can impair insulin action, directly and/or through several changes occurring in different tissues. Body fat excess, which is another common feature in these women, can contribute to worsening the whole picture. Nevertheless, insulin resistance may also be found in many normal-weight individuals. Endocrine and metabolic abnormalities can develop in different moments, and probably there is fetal programming of these alterations. However, a number of vicious circles, with bidirectional relationships between androgen excess and insulin resistance, and with the contribution of several other factors, make it extremely difficult to understand where this process really originates. This review summarizes available evidence on this topic, in order to better understand the complex relationships linking hyperandrogenism and impaired insulin action in women with PCOS.

Assessment of Early Markers of Cardiovascular Risk in Polycystic Ovary Syndrome

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Molecular Mechanisms of Laparoscopic Ovarian Drilling and Its Therapeutic Effects in Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a common endocrinopathy, characterized by chronic anovulation, hyperandrogenism, and multiple small subcapsular cystic follicles in the ovary during ultrasonography, and affects 5–10% of women of reproductive age. PCOS is frequently associated with insulin resistance (IR) accompanied by compensatory hyperinsulinemia and, therefore, presents an increased risk of type 2 diabetes mellitus (DM). The pathophysiology of PCOS is unclear, and many hypotheses have been proposed. Among these hypotheses, IR and hyperandrogenism may be the two key factors. The first line of treatment in PCOS includes lifestyle changes and body weight reduction. Achieving a 5–15% body weight reduction may improve IR and PCOS-associated hormonal abnormalities. For women who desire pregnancy, clomiphene citrate (CC) is the front-line treatment for ovulation induction. Twenty five percent of women may fail to ovulate spontaneously after three cycles of CC treatment, which is called CC-resistant PCOS. For CC-resistant PCOS women, there are many strategies to improve ovulation rate, including medical treatment and surgical approaches. Among the various surgical approaches, one particular surgical method, called laparoscopic ovarian drilling (LOD), has been proposed as an alternative treatment. LOD results in an overall spontaneous ovulation rate of 30–90% and final pregnancy rates of 13–88%. These benefits are more significant for women with CC-resistant PCOS. Although the intra- and post-operative complications and sequelae are always important, we believe that a better understanding of the pathophysiological changes and/or molecular mechanisms after LOD may provide a rationale for this procedure. LOD, mediated mainly by thermal effects, produces a series of morphological and biochemical changes. These changes include the formation of artificial holes in the very thick cortical wall, loosening of the dense and hard cortical wall, destruction of ovarian follicles with a subsequently decreased amount of theca and/or granulosa cells, destruction of ovarian stromal tissue with the subsequent development of transient but purulent and acute inflammatory reactions to initiate the immune response, and the continuing leakage or drainage of “toxic” follicular fluid in these immature and growth-ceased pre-antral follicles. All these factors contribute to decreasing local and systemic androgen levels, the following apoptosis process with these pre-antral follicles to atresia; the re-starting of normal follicular recruitment, development, and maturation, and finally, the normalization of the “hypothalamus–pituitary–ovary” axis and subsequent spontaneous ovulation. The detailed local and systematic changes in PCOS women after LOD are comprehensively reviewed in the current article.

Polycystic Ovary Syndrome and Gender Identity

Polycystic ovary syndrome (PCOS) is a common endocrinopathy affecting 46XX individuals of reproductive age. Cardinal features of PCOS include hyperandrogenism, irregular periods, and insulin resistance. Pathogenesis is unclear but likely involves hypothalamic, pituitary, or ovarian abnormalities leading to increased androgen production. In addition, alternative insulin signaling pathways are activated to preserve ovarian sensitivity to insulin while other "classical" tissues (e.g. liver, adipose, muscle) are insulin resistant. Treatment targets specific symptoms and the most common regimens include weight loss, metformin, oral contraceptives, anti-androgen compounds, and fertility treatments. Observations of individuals with gene mutations affecting androgen metabolism suggest that androgens may influence the development of gender identity. We reviewed studies exploring the relationship between gender identity and PCOS to further elucidate this relationship. Rates of PCOS in hormone-naïve transmasculine (TM) individuals appear to be higher than in the general population as cited by small, early studies using convenience samples and inconsistent criteria for PCOS. A more recent, larger study using established guidelines for PCOS did not show this to be true. Further, other studies show that although PCOS patients are less likely to identify with a traditional feminine gender scheme compared to age-matched peers, the prevalence of gender incongruence in PCOS patients is not higher than in the general population. Larger systematic studies with control groups using modern diagnostic criteria for both PCOS and gender incongruence are needed to clarify the relationship between PCOS and gender identity.

The Role of Zinc in Selected Female Reproductive System Disorders

Zinc is an essential microelement that plays many important functions in the body. It is crucial for the regulation of cell growth, hormone release, immunological response and reproduction. This review focuses on its importance in the reproductive system of women of reproductive and postmenopausal ages, not including its well described role in pregnancy. Only recently, attention has been drawn to the potential role of zinc in polycystic ovary syndrome (PCOS), dysmenorrhea, or endometriosis. This review is mainly based on 36 randomized, controlled studies on reproductive, pre- and post-menopausal populations of women and on research trying to explain the potential impact of zinc and its supplementation in the etiology of selected female reproductive system disorders. In women with PCOS, zinc supplementation has a positive effect on many parameters, especially those related to insulin resistance and lipid balance. In primary dysmenorrhea, zinc supplementation before and during each menstrual cycle seems to be an important factor reducing the intensity of menstrual pain. On the other hand, little is known of the role of zinc in endometriosis and in postmenopausal women. Therefore, further studies explaining the potential impact of zinc and its supplementation on female reproductive system would be highly advisable and valuable.

A Systematic Review of the Effects of Exercise on Hormones in Women with Polycystic Ovary Syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common endocrine disorder that is characterized by menstrual irregularity and elevated serum androgens, and is often accompanied by insulin resistance. The etiology of PCOS is unknown. Lifestyle interventions and weight loss, where appropriate, remain first-line treatments for women with PCOS. Regular physical activity is recommended for women with PCOS to maintain a healthy weight and cardiovascular fitness.

PURPOSE

To review the evidence for the impact of various exercise interventions on hormone levels in women with PCOS.

METHODS

A systematic review of original studies indexed in PubMed that utilized an exercise intervention in women with PCOS and reported hormone values pre- and post-intervention. Studies in which the effects of the exercise intervention could be determined were included.

RESULTS

Vigorous aerobic exercise improves insulin measures in women with PCOS. Resistance or strength training may improve androgen levels, though additional studies are warranted. Studies with yoga are limited but suggest improvements in androgens. Limited information is available on the impact of exercise on adipokines and anti-Müllerian hormone, warranting further investigation.

CONCLUSIONS

Recommended guidelines for women with PCOS include vigorous aerobic exercise and resistance training to improve measures of insulin sensitivity and androgen levels.

The role of advanced glycation end products in human infertility

Advanced glycation end products (AGEs) are heterogeneous products of the non-enzymatic interaction between proteins and reducing sugars. Numerous studies have shown that AGEs are associated with senescence, diabetes, vascular disease, aging and kidney disease. Infertility has been affected approximately 10 to15% of couples of reproductive ages. AGEs accumulation has been shown to play a crucial role in pathogenesis of infertility-related diseases. The present review provides the generation process, mechanism and pathological significance of AGEs and the novel treatment targeting AGEs for infertility.

Effects of lifestyle modification in polycystic ovary syndrome compared to metformin only or metformin addition: A systematic review and meta-analysis

Polycystic ovary syndrome (PCOS) is a common disease that has an effect on approximately 10% of women of childbearing age. Although there is evidence regarding the role of lifestyle factors in the development of PCOS, the exact etiology remains unclear. Additionally, metformin is used in the treatment of PCOS but its role remains unclear. We compared the effects of lifestyle modification (LSM) + metformin and metformin alone on PCOS. We performed a systematic review by searching electronic databases for publications until December 2019. The primary endpoints were clinical outcomes, such as menstrual cycles and pregnancy rates, and the secondary endpoints were anthropometric, metabolic, and androgenic parameters. The meta-analysis revealed that there was no significant difference in the improvements in the menstrual cycles between LSM and metformin alone (weighted mean difference [MD] = 1.62) and between LSM + metformin and LSM (MD = 1.20). The pregnancy rates and body mass indices were not significantly different between LSM and metformin alone (MD = 1.44 and −0.11, respectively). LSM reduced insulin resistance (MD = −0.52) and increased serum levels of sex hormone-binding globulins (MD = 8.27) compared with metformin. Therefore, we suggest recommending lifestyle modifications actively to women with PCOS if they do not have indications for metformin.

Metabolic dysfunction in polycystic ovary syndrome: Pathogenic role of androgen excess and potential therapeutic strategies

Background

Polycystic ovary syndrome (PCOS) is the most common endocrinopathy among reproductive age women. Although its cardinal manifestations include hyperandrogenism, oligo/anovulation, and/or polycystic ovarian morphology, PCOS women often display also notable metabolic comorbidities. An array of pathogenic mechanisms have been implicated in the etiology of this heterogeneous endocrine disorder; hyperandrogenism at various developmental periods is proposed as a major driver of the metabolic and reproductive perturbations associated with PCOS. However, the current understanding of the pathophysiology of PCOS-associated metabolic disease is incomplete, and therapeutic strategies used to manage this syndrome's metabolic complications remain limited.

Scope of review

This study is a systematic review of the potential etiopathogenic mechanisms of metabolic dysfunction frequently associated with PCOS, with special emphasis on the metabolic impact of androgen excess on different metabolic tissues and the brain. We also briefly summarize the therapeutic approaches currently available to manage metabolic perturbations linked to PCOS, highlighting current weaknesses and future directions.

Major conclusions

Androgen excess plays a prominent role in the development of metabolic disturbances associated with PCOS, with a discernible impact on key peripheral metabolic tissues, including the adipose, liver, pancreas, and muscle, and very prominently the brain, contributing to the constellation of metabolic complications of PCOS, from obesity to insulin resistance. However, the current understanding of the pathogenic roles of hyperandrogenism in metabolic dysfunction of PCOS and the underlying mechanisms remain largely incomplete. In addition, the development of more efficient, even personalized therapeutic strategies for the metabolic management of PCOS patients persists as an unmet need that will certainly benefit from a better comprehension of the molecular basis of this heterogeneous syndrome.

Implicating androgen excess in propagating metabolic disease in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) has been traditionally perceived as a reproductive disorder due to its most common presentation with menstrual dysfunction and infertility. However, it is now clear that women with PCOS are at increased risk of metabolic dysfunction, from impaired glucose tolerance and type 2 diabetes mellitus to nonalcoholic fatty liver disease and cardiovascular disease. PCOS is characterised by androgen excess, with cross-sectional data showing that hyperandrogenism is directly complicit in the development of metabolic complications. Recent studies have also shown that C11-oxy _C19 androgens are emerging to be clinically and biochemically significant in PCOS, thus emphasising the importance of understanding the impact of both classic and C11-oxy _C19 androgens on women's health. Here we discuss androgen metabolism in the context of PCOS, and dissect the role played by androgens in the development of metabolic disease through their effects on metabolic target tissues in women.

From Prediabetes to Type 2 Diabetes Mellitus in Women with Polycystic Ovary Syndrome: Lifestyle and Pharmacological Management

AIMS

Despite the very clear association between polycystic ovary syndrome (PCOS) and dysglycemia, few studies have explored the continuum of glycemic alterations leading from minor glucose abnormalities to overt diabetes. The purpose of this review is to trace the natural history of glycemic alteration in women with PCOS.

METHODS

We performed a literature review without time limit until August 2019. Inclusion criteria were studies addressing the association between impaired glucose tolerance or impaired fasting glucose or type 2 diabetes (T2D) and PCOS with at least an English abstract. The exclusion criteria were no PCOS or impaired glucose tolerance or impaired fasting glucose or T2D as outcome. The outcomes of interest were the onset of impaired glucose tolerance, impaired fasting glucose, T2D, and the progression from impaired glucose tolerance or impaired fasting glucose to T2D.

RESULTS

Healthy diet and physical activity are the first-line therapy for PCOS. Treatment with metformin was associated with significant lower 2-hour postload glucose levels and with reduction in fasting glucose when compared to placebo. Thiazolidinediones were more effective in reducing fasting glucose levels compared to placebo. Metformin and pioglitazone treatments showed similar effects on fasting glucose levels. The sodium-glucose cotransporter-2 inhibitor empagliflozin did not show differences in metabolic parameters when compared to metformin. The combination therapy with metformin plus the glucagon-like peptide-1 receptor agonist liraglutide was associated with significant improvements in basal and postload glucose levels compared with only liraglutide. Likewise, a combination therapy with the dipeptidyl peptidase-4 inhibitor saxagliptin and metformin demonstrated superiority versus metformin in fasting glucose and oral glucose tolerance test normalization. Myo-inositol supplementation was associated with lower insulin levels, glucose levels, and insulin resistance when compared with placebo, metformin, or estrogen treatments.

CONCLUSIONS

The use of insulin-sensitizing agents, such as metformin and inositols, along with lifestyle interventions may improve the metabolic profile in PCOS women.

Elevated chemerin induces insulin resistance in human granulosa-lutein cells from polycystic ovary syndrome patients

The insulin resistance (IR) of ovarian granulosa cells from polycystic ovary syndrome (PCOS) aggravates the abnormalities in steroidogenesis and anovulation, and chemerin is an adipokine involved in regulating adipogenesis and glucose homeostasis. The role and underlying mechanism of chemerin in developing IR of the granulosa cells from PCOS remain unclear. Plasma, follicular fluid, and human granulosa-lutein cells (hGLs) were collected from non-PCOS and patients with PCOS with or without IR. The chemerin levels were elevated in both follicular fluid and hGL samples from patients with PCOS with IR, and the hGLs from patients with PCOS with IR showed decreased insulin sensitivity and impaired glucose uptake capacity. Moreover, treatment of chemerin attenuated insulin-stimulated glucose uptake by decreasing phosphorylation of insulin receptor substrate (IRS)1/2 Tyr612, phosphorylation of protein kinase B Ser473, and membrane translocation of glucose transporter type 4 through increasing Ser307 phosphorylation of IRS1 in cultured hGLs. These effects could be abolished by small interfering RNA-mediated knockdown of chemokine-like receptor 1. Furthermore, insulin induced the expression of chemerin in hGLs. Our findings demonstrate a novel role of chemerin in the metabolic dysfunction of PCOS, which suggested that chemerin and its receptor can be further implicated as potential therapeutic targets in the future treatment of PCOS.-Li, X., Zhu, Q., Wang, W., Qi, J., He, Y., Wang, Y., Lu, Y., Wu, H., Ding, Y., Sun, Y. Elevated chemerin induces insulin resistance in human granulosa-lutein cells from polycystic ovary syndrome patients.

Excess androgen production in subcutaneous adipose tissue of women with polycystic ovarian syndrome is not related to insulin or LH

The purpose of this study was to investigate androgen production and the role of insulin and LH in its regulation in subcutaneous adipose tissue (SAT) of women with polycystic ovarian syndrome (PCOS). Protein and mRNA expression of androgen synthesis enzymes (Cytochrome P450 17A1 [CYP17A1] and Aldo-keto reductase 1C3 [AKR1C3]) were measured in SAT biopsies from women with PCOS, diagnosed according to the Rotterdam criteria (n=15) and healthy controls (n=15). Cultured mature adipocytes (differentiated from SAT biopsies) were treated with insulin ± phosphoinositol-3-kinase inhibitor (LY294002) or LH ± insulin. CYP17A1 and AKR1C3 mRNA expression and testosterone concentrations were measured in treated and untreated adipocyte cultures. AKR1C3 mRNA was significantly (P<0.001) greater in PCOS versus non-PCOS SAT, but CYP17A1 was not significantly different between the two groups. AKR1C3 and CYP17A1 protein expression was not significantly different in PCOS versus non-PCOS SAT. In untreated adipocyte cultures, CYP17A1, AKR1C3 and testosterone levels were significantly higher in the PCOS versus the non-PCOS groups. Addition of insulin increased AKR1C3 mRNA and testosterone levels, but not CYP17A1 mRNA in non-PCOS with no effect on PCOS adipocytes. The stimulatory effects of insulin were not inhibited by LY294002. Addition of LH increased CYP17A1, AKR1C3 and testosterone in non-PCOS adipocytes with no effect in PCOS adipocytes. In conclusion, SAT of women with PCOS produces excess androgen, which may contribute to PCOS-related hyperandrogenaemia. This SAT androgen excess is independent of obesity and is not directly stimulated by insulin or LH.