Defects in insulin receptor signaling in vivo in the polycystic ovary syndrome (PCOS)

Impaired glucose tolerance and insulin resistance in a prenatally-androgenized rat model of polycystic ovary syndrome in later life

Polycystic ovary syndrome (PCOS), one of the most common endocrine disorders in reproductive-aged women, is associated with metabolic disturbances. The present study aimed to examine changes in body weight (BW) and glucose and insulin tolerance in a prenatally-androgenized (PNA) rat model of PCOS compared to control with increasing age. Pregnant rats in the experimental group were subcutaneously injected with 5 mg of free testosterone on the 20th day of pregnancy, while the control group received the solvent. Female offspring of both groups, PNA rats (rat model of PCOS) and control, were examined in terms of changes in BW, glucose and insulin tolerance at 3, 6, 12 and 20 months of age. BW at birth (6.53 ± 0.89 vs. 5.60 ± 1.18 g; P = 0.038), 15 (25 ± 1.15 vs. 22.36 ± 3.98 g; P = 0.019) and 30 (59.37 ± 10.19 vs.49.9 ± 9.39 g; P = 0.022) days of age was significantly increased in the rat model of PCOS compared to control, but no significant differences were observed in BW of the rat model of PCOS compared to control at 60 (P = 0.155) and 75 (P = 0.932) days or at 3 (P = 0.239), 6 (P = 0.782), 12 (P = 0.755) and 20 (P = 0.092) months of age. Rat model of PCOS showed impaired glucose tolerance (IGT) at 3 months of age (P = 0.020) and insulin resistance (IR) with increasing age (3-20 months of age) compared to control. Increased BW before puberty, IGT at 3 months of age and IR with increasing age were observed in our rat model of PCOS. This rat model may contribute to a better understanding of underlying mechanisms of changes in BW, IGT and IR in future studies.

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.

Effect of Zinc on Blood Biochemical and mTOR Gene Expression in Rats with Polycystic Ovarian

Zinc (Zn) is a significant element of the reproductive system and is associated with several enzymes that regulate different metabolic pathways. Organic Zn can significantly affect polycystic ovarian syndrome (PCOS) pathogenesis. Insulin resistance (IR) is a common complication of PCOS. Mammalian target of rapamycin (mTOR), which controls crucial cell functions, is regulated by insulin and nutrients. It has two complexes, namely, mTORC1 and mTORC2. mTOR associates with its binding partner's regulatory associated protein of mTOR (Raptor) and rapamycin-insensitive companion of mTOR (Rictor), which form these distinct complexes, respectively, and is activated in PCOS. This research aimed to evaluate the effect of Zn on the expression of mTOR signaling genes (Raptor and Rictor) and IR in PCOS model rats. Different Zn supplements, including standard diet (SD): (control - or + , SD without supplementation), Zn25, Zn75, and Zn175 (daily given three levels of 25, 75, and 175 mg Zn methionine (ZnMet)/kg for 6 weeks, respectively), were applied to the control and PCOS groups. Fasting glucose (FG), fasting insulin (FI), IR indices, and Raptor and Rictor expression levels were measured in both groups. The results showed that PCOS induction dramatically increased FG, FI, IR indices, and mTOR-related gene expression; however, different Zn supplementation concentrations, especially at 75 mg/kg, reduced the effects of PCOS induction. Organic Zn collectively exerted positive effects on Estradiol Valerate (EV)-induced PCOS rats by reducing IR and mTOR signaling gene (i.e., Raptor and Rictor) expression. Moreover, this study revealed a correlation between Zn and IR. Therefore, Zn supplementation could be a valuable therapeutic method for treating PCOS.

When IGF-1 Meets Metabolic Inflammation and Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder associated with insulin resistance (IR) and hyperandrogenaemia (HA). Metabolic inflammation (MI), characterized by a chronic low-grade inflammatory state, is intimately linked with chronic metabolic diseases such as IR and diabetes and is also considered an essential factor in the development of PCOS. Insulin-like growth factor 1 (IGF-1) plays an essential role in PCOS pathogenesis through its multiple functions in regulating cell proliferation metabolic processes and reducing inflammatory responses. This review summarizes the molecular mechanisms by which IGF-1, via MI, participates in the onset and progression of PCOS, aiming to provide insights for studies and clinical treatment of PCOS.

Insights into Vitamin E with Combined Oral Contraceptive on INSR Gene in PCOS by Integrating In Silico and In Vivo Approaches

Polycystic ovarian syndrome (PCOS) is a hormone disorder common among reproductive-aged women. This is associated with the symptoms like an irregular menstrual cycle, excess androgens, and polycystic ovary. Interestingly, vitamin E acts like the hormone progesterone and improves insulin sensitivity in PCOS. The study aims to evaluate the therapeutic effect of vitamin E in combination with combined oral contraceptive (COC) against PCOS by in silico and in vivo methods. The therapeutic effect of vitamin E (25 and 50mg/kg) in combination with COC (0.4mg/kg) was screened by the in silico method using Auto dock vina 4.2.6. Additionally, in vivo studies with a letrozole-induced PCOS model were performed in 30 female SD rats (n = 6 in each group) for 8 weeks with different doses of vitamin E. Furthermore, histopathological features and the insulin receptor (INSR) gene were scrutinized. An in silico study showed that drospirenone and vitamin E have an excellent affinity to bind to INSR and have higher binding energy (- 8.5 kcal/mol and - 8.7 kcal/mol, respectively). In vivo results showed a significant reduction in elevated testosterone levels compared to that of the PCOS group; follicle-stimulating hormone (FSH) and insulin levels also showed significant changes and reversed anti-oxidant levels in a dose-dependent manner. Ovarian histopathological changes were observed in different follicle counts in addition to the INSR gene, which showed changes in densitometry values. Supplementation of vitamin E combined with COC could be effective against PCOS, and clinical studies must be carried out further.

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.

Health-related physical fitness in women with polycystic ovary syndrome versus controls: a systematic review and meta-analysis

INTRODUCTION

Polycystic ovary syndrome (PCOS) is a common endocrinopathy associated with cardiometabolic dysfunction.

PURPOSE

(1) To compare HRPF indices, including cardiorespiratory fitness (CRF), muscle strength, and muscle endurance, between women with and without PCOS (i.e., controls). (2) To explore the impact of moderating factors, i.e., insulin sensitivity, androgen levels, physical activity levels, and body mass index, on these indices.

METHODS

Articles comparing HRPF between PCOS and control groups were identified until February 27th, 2022. Random-effects meta-analyses were conducted and moderating factors were explored with subgroup and meta-regression analyses.

RESULTS

Twenty studies were included. Compared to controls, CRF was lower in women with PCOS (n = 15, - 0.70 [- 1.35, - 0.05], P = 0.03, I2 = 95%). Meta-regression analyses demonstrated that fasting insulin (P = 0.004) and homeostatic model assessment of insulin resistance (P = 0.006) were negatively associated with CRF, while sex-hormone binding globulin levels (P = 0.003) were positively associated. Absolute muscle strength was not different between PCOS and controls (n = 7, 0.17 [- 0.10, 0.45], P = 0.22, I2 = 37%). One study evaluated muscle endurance and reported lower core endurance in PCOS subjects compared to controls.

CONCLUSION

These data suggest that PCOS may be associated with impaired CRF. It remains unclear whether muscle strength and endurance differ between women with PCOS and controls. As this data set was limited by a small sample size, potential for bias, and inconsistent findings, additional studies accounting for the heterogeneous presentation of PCOS as well as improved matching between PCOS and controls for characteristics known to affect HRPF would help elucidate the impact of PCOS on indices of HRPF.

PROSPERO REGISTRATION NUMBER

CRD42020196380.

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.

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.

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.

Insulin resistance in polycystic ovary syndrome across various tissues: an updated review of pathogenesis, evaluation, and treatment

Polycystic ovary syndrome (PCOS) is a common endocrine disorder characterized by chronic ovulation dysfunction and overabundance of androgens; it affects 6-20% of women of reproductive age. PCOS involves various pathophysiological factors, and affected women usually have significant insulin resistance (IR), which is a major cause of PCOS. IR and compensatory hyperinsulinaemia have differing pathogeneses in various tissues, and IR varies among different PCOS phenotypes. Genetic and epigenetic changes, hyperandrogenaemia, and obesity aggravate IR. Insulin sensitization drugs are a new treatment modality for PCOS. We searched PubMed, Google Scholar, Elsevier, and UpToDate databases in this review, and focused on the pathogenesis of IR in women with PCOS and the pathophysiology of IR in various tissues. In addition, the review provides a comprehensive overview of the current progress in the efficacy of insulin sensitization therapy in the management of PCOS, providing the latest evidence for the clinical treatment of women with PCOS and IR.

Endocrine Disrupting Chemicals in Polycystic Ovary Syndrome: The Relevant Role of the Theca and Granulosa Cells in the Pathogenesis of the Ovarian Dysfunction

Polycystic ovary syndrome (PCOS) is the most common heterogeneous endocrine disorder among women of reproductive age. The pathogenesis of PCOS remains elusive; however, there is evidence suggesting the potential contribution of genetic interactions or predispositions combined with environmental factors. Among these, endocrine disrupting chemicals (EDCs) have been proposed to potentially contribute to the etiology of PCOS. Granulosa and theca cells are known to cooperate to maintain ovarian function, and any disturbance can lead to endocrine disorders, such as PCOS. This article provides a review of the recent knowledge on PCOS pathophysiology, the role of granulosa and theca cells in PCOS pathogenesis, and the evidence linking exposure to EDCs with reproductive disorders such as PCOS.

Therapeutic Investigation of Standardized Aqueous Methanolic Extract of Bitter Melon (Momordica charantia L.) for Its Potential against Polycystic Ovarian Syndrome in Experimental Animals’ Model: In Vitro and In Vivo Studies

Polycystic ovarian syndrome (PCOS) is an heterogenous, endocrine, metabolic, and multidisciplinary disorder of reproductive-aged females that aggravates insulin resistance, hyperandrogenism, obesity, menstrual irregularities, and infertility. Bitter melon is consumed as vegetable in various parts of the world. The purpose of this study was to provide the rationale for the folkloric uses of bitter melon (Momordica charantia L.) in reproductive abnormalities. HPLC analysis of standardized aqueous methanolic extract of bitter melon revealed the presence of various phytochemicals such as quercetin, gallic acid, benzoic acid, chlorogenic acid, syringic acid, p-coumaric acid, ferulic acid, and cinnamic acid. Twenty-five Swiss albino adult female rats (120–130 g) were acquired and divided into two groups (5 + 20). Letrozole (1 mg/kg p.o.) was used for four weeks to induce PCOS in twenty rats. Disease induction was confirmed by vaginal smear cytology analysis under the microscope. Animals were further divided into four groups, with one group as PCOS group, and the remaining three are treated with standardized extract of bitter melon (500 mg/kg p.o.), bitter melon plus metformin (500 mg/kg p.o.), and metformin alone for the period of next four weeks. After four weeks, the rats were euthanized at diestrus stage. Ovaries of the experimental animals were removed and fixed in 10% buffered formalin, and blood samples were obtained from direct cardiac puncture and stored. Ovaries histopathological analysis showed cystic follicles (9–10) in PCOS group, while, in all the treatment groups, we found developing and mature follicles. Similarly, hormone analysis showed significant (p < 0.001) reduction of LH surge, insulin, and testosterone levels and improvement in FSH levels. Lipid profile and antioxidant enzymes status were also significantly (p < 0.001) improved. In conclusion, the study validates the bitter melon potential as an insulin sensitizer and ovulation enhancer and authenticates its potential in PCOS management.

Factors influencing the prevalence of polycystic ovary syndrome (PCOS) in the United Arab Emirates

Statistics indicate that at least 20-25% of women suffer from PCOS in the Gulf region. Despite its prevalence and negative implications on reproductive, metabolic, and physiological heath the exact cause of PCOS is unknown, in part due to the diversity of symptoms manifested by this disorder. In this review, we investigate causes of PCOS globally and draw on these studies, to determine the potential contributing factors for PCOS pathogenesis in the UAE population. The most frequently identified factors promoting PCOS pathogenesis that may be pertinent to this population include physiological factors such as insulin resistance, vitamin D deficiency, genetic factors, obesity, and anti-mullerian hormone (AMH) levels in the body as well as environmental factors such as air pollution, endocrine disrupting chemicals, and pesticide use. This evidence will help inform healthcare workers and government agencies to set up optimal guidelines for control and awareness of PCOS in the UAE.

Rhamnocitrin Attenuates Ovarian Fibrosis in Rats with Letrozole-Induced Experimental Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a common endocrine-related cause of infertility in women and has an unknown etiology. Studies have shown that rhamnocitrin (Rha) exhibits positive effects on the reproductive system. This study investigated Rha's antifibrotic effects on PCOS rats and revealed its underlying mechanisms. Female SD rats were randomized into 4 groups (n = 8, each); the control group received tea oil by intraperitoneal injection and 1% w/v CMC by oral gavage; the PCOS group received letrozole (1 mg/kg); the PCOS+Rha group received letrozole and Rha (5 mg/kg); the PCOS+Met group received letrozole and Met (265 mg/kg) for 21 days. At the study end, Rha treatment restored letrozole-induced alterations in the relative ovarian weights, body weight, and relative weights of uterine and visceral adipose tissues. Histological observation showed that Rha ameliorates ovarian structure and fibrosis in PCOS. Administration of Rha reduced letrozole-induced metabolic dysfunction by ameliorating the levels of TC, TG, and HDL-C in the PCOS rats. Rha treatment also modulated the serum levels of sex hormones, which decreased T, E2, and LH and increased FSH in PCOS rats. In addition, Rha treatment modulated insulin resistance and increased gene expression of antioxidant enzymes (Cat, Sod2, Gpx3, Mgst1, Prdx3, Gsta4, Gsr, and Sod1) in the ovaries of the PCOS rats. Finally, Rha treatment appeared to increase the activity of PPAR-γ and inhibit the TGF-β1/Smad pathway in the ovaries of the PCOS rats. Our findings suggest that Rha significantly ameliorated metabolic disturbances and ovarian fibrosis in the PCOS rats. Rha perhaps is an effective compound for preventing ovarian fibrosis in the future.

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.

Genome-Wide Transcriptome Analysis in Type 2 Diabetes Patients Treated by Sitagliptin

OBJECTIVE

In this study, transcriptome sequencing was performed on patients with type 2 diabetes mellitus treated with different prognosis to explore the differential level genes of different hypoglycemic effects of sitagliptin.

METHODS

Patients with newly diagnosed T2DM (within six months of diagnosis) were selected as the study subjects. Patients were given sitagliptin 100 mg once a day orally. After 12 weeks of regular drug therapy, the reduction in glycated hemoglobin was compared before and after drug administration. The patients were then divided into two groups: the significantly effective group (M) and the less effective group (N). High-throughput sequencing of the transcriptome was conducted to detect the differential expression levels of genes in peripheral blood mononuclear cells. Expanded sample size validation of the candidate differential genes was conducted using reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

After 12 weeks of treatment with sitagliptin, high-throughput sequencing of the transcriptome found that expression of the following genes was different when comparing the significantly effective group (M) and the less effective group (N): ghrelin (GHRL), insulin-like growth factor-1 receptor (IGF1R), mitogen-activated protein kinase-3 (MAPK3), phosphatidylinositol-4,5-bisphosphonate 3-kinase, catalytic subunit delta (PIK3CD), and the suppressor of cytokine signaling-3 (SOCS3). The validation results of RT-PCR showed that, in the significantly effective group (M), the expression of IGF1R was significantly increased (P = 0.034), the expression of MAPK3 was significantly reduced (P = 0.002), and the expression of SOCS3 was also significantly reduced (P < 0.001).

CONCLUSION

There was a significant difference in gene level between patients with significant hypoglycemic effect and patients with poor hypoglycemic effect, and the expression of IGF1R increased and the expression of MAPK3 and SOCS3 decreased.

Pathophysiologic Mechanisms of Insulin Secretion and Signaling-Related Genes in Etiology of Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a common endocrinopathy in women. PCOS is characterized by anovulation, hyperandrogenism, polycystic ovaries, insulin resistance, and obesity. Despite the finding that the genetic origin of PCOS is well demonstrated in previous twin and familial clustering studies, genes and factors that can exactly explain the PCOS pathophysiology are not known. Objective(s). In this review, we attempted to identify genes related to secretion and signaling of insulin aspects of PCOS and their physiological functions in order to explain the pathways that are regulated by these genes which can be a prominent function in PCOS predisposition. Materials and Methods. For this purpose, published articles and reviews dealing with genetic evaluation of PCOS in women from peer-reviewed journals in PubMed and Google Scholar databases were included in this review. Results. The genomic investigations in women of different populations identified many candidate genes and loci that are associated with PCOS. The most important of them are INSR, IRS1-2, MTNR1A, MTNR1B, THADA, PPAR-γ2, ADIPOQ, and CAPN10. These are mainly associated with metabolic aspects of PCOS. Conclusions. In this review, we proposed that each of these genes may interrupt specific physiological pathways by affecting them and contribute to PCOS initiation. It is clear that the role of genes involved in insulin secretion and signaling is more critical than other pathways.

Clinical Manifestations of Hyperandrogenism and Ovulatory Dysfunction Are Not Associated with His1058 C/T SNP (rs1799817) Polymorphism of Insulin Receptor Gene Tyrosine Kinase Domain in Kashmiri Women with PCOS

BACKGROUND

Polycystic ovary syndrome (PCOS) is the most common endocrine metabolic disorder affecting premenopausal women. Besides primary features like anovulation, hyperandrogenism, and polycystic ovaries, women with PCOS present with multiple metabolic, cardiovascular, and psychological disorders. The etiology is multifactorial and the different genetic variants are suggested to play an important role in pathogenesis. Insulin resistance is a ubiquitous finding in PCOS and SNPs in genes involved in the insulin signaling pathway are possible candidates that can explain the development of clinical manifestations of PCOS.

AIM

We aimed to investigate the association of INSR His1058 C/T (rs1799817) single nucleotide polymorphism with PCOS in Kashmiri women. The genotypic-phenotypic correlation of the tested SNP with hyperandrogenism, ovulatory dysfunction, and metabolic markers was evaluated.

RESULTS

The allele frequency (OR = 1.00, 95% CI = 0.67-1.48, χ 2 = 0.01, P=0.99) and genotype distribution (χ 2 = 3.73, P=0.15) in INSR C/T polymorphism were comparable with controls. No significant association was found with PCOS in dominant (P=0.194), recessive (P=0.442), and homo vs. het. (P=0.5) genotype models. Genotype-phenotype correlation analysis revealed that variant TT genotype had significantly higher HOMA (P=0.029) and reduced insulin sensitivity QUICKI (P=0.037) values. There was no significant variation in the prevalence of hirsutism, acne, alopecia, menstrual disturbances, acanthosis nigricans, and obesity (all P > 0.05) in different INSR C/T genotypes.

CONCLUSION

The INSR C/T SNP (rs1799817) does not increase the risk of PCOS in Kashmiri women. This SNP is unlikely to play a significant role in the development and manifestation of clinical symptoms of polycystic ovary syndrome.

Non-cell autonomous mechanisms control mitochondrial gene dysregulation in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common endocrine disorder associated with insulin resistance and impaired energy metabolism in skeletal muscle, the aetiology of which is currently unclear. Here, we mapped the gene expression profile of skeletal muscle from women with PCOS and determined if cultured primary myotubes retain the gene expression signature of PCOS in vivo. Transcriptomic analysis of vastus lateralis biopsies collected from PCOS women showed lower expression of genes associated with mitochondrial function, while the expression of genes associated with the extracellular matrix was higher compared to controls. Altered skeletal muscle mRNA expression of mitochondrial-associated genes in PCOS was associated with lower protein expression of mitochondrial complex II-V, but not complex I, with no difference in mitochondrial DNA content. Transcriptomic analysis of primary myotube cultures established from biopsies did not display any differentially expressed genes between controls and PCOS. Comparison of gene expression profiles in skeletal muscle biopsies and primary myotube cultures showed lower expression of mitochondrial and energy metabolism-related genes in vitro, irrespective of the group. Together, our results show that the altered mitochondrial-associated gene expression in skeletal muscle in PCOS is not preserved in cultured myotubes, indicating that the in vivo extracellular milieu, rather than genetic or epigenetic factors, may drive this alteration. Dysregulation of mitochondrial-associated genes in skeletal muscle by extracellular factors may contribute to the impaired energy metabolism associated with PCOS.

Serum X-box-binding protein 1 levels in PCOS patients

OBJECTIVE

X-box binding protein-1 (XBP1) is a possible indicator of metabolic syndrome and diabetes. This study aimed to evaluate the relationship between serum XBP1 levels and polycystic ovary syndrome (PCOS).

METHOD

A prospective observational study was conducted with 88 patients. The first group was defined as the control group with ovulatory and normal-BMI patients (n = 28). The second group comprised of nonobese PCOS patients (n = 30). The third group included overweight/obese patients with PCOS (n = 30). Fasting plasma glucose, serum lipids, follicle stimulating hormone, luteinizing hormone, total testosterone, dehydroepiandrosterone and XBP1 levels l were evaluated in all groups.

RESULTS

There was a significant difference in XBP1 levels between the study groups, and higher levels were observed both in the nonobese and obese PCOS groups than in the healthy controls (p < .001). The median level of XBP1 was 73.7 pg/ml in the control group, 114.11 pg/ml in the nonobese PCOS group, and 151.61 pg/ml in the overweight/obese PCOS group. A cutoff level of XBP1 at 95.79 pg/ml level was determined with a significant AUC (area under the curve) level of 99% and high specificity and sensitivity rates to predict PCOS. Also, a significant positive correlation was observed between XBP1 levels and BMI, waist circumference, fasting plasma glucose and triglyceride levels (p < .05).

CONCLUSIONS

XBP1 levels were significantly higher in PCOS patients, particularly in overweight/obese PCOS patients, than in the controls. Also, the parameters associated with metabolic syndrome were related to XBP1 levels.

Obesity, but not hyperandrogenism or insulin resistance, predicts skeletal muscle mass in reproductive-aged women with polycystic ovary syndrome: A systematic review and meta-analysis of 45 observational studies

Women with polycystic ovary syndrome (PCOS) exhibit reduced muscle insulin-mediated glucose uptake, potentially attributed to altered muscle mass; however, this is inconclusive. Altered muscle mass may aggravate PCOS complications. Our systematic review and meta-analysis evaluated whether PCOS alters muscle mass and function. Databases (MEDLINE, Web of Science, Scopus) were searched through September 2, 2020, for studies documenting skeletal muscle mass (lean tissue mass) and function (strength) in PCOS and control groups. The primary outcome was total lean body mass (LBM) or fat-free mass (FFM). Data were pooled by random-effects models and expressed as mean differences and 95% confidence intervals. Forty-five studies (n = 3676 participants) were eligible. Women with PCOS had increased total (0.83 [0.08,1.58] kg; p = 0.03; I²  = 72.0%) yet comparable trunk (0.84 [-0.37,2.05] kg; p = 0.15; I²  = 73.0%) LBM or FFM versus controls. Results of meta-regression analyses showed no associations between mean differences between groups in total testosterone or homeostatic model assessment of insulin resistance and total or trunk LBM or FFM (All: p ≥ 0.75). Mean differences in body mass index (BMI) were associated with total (0.65 [0.23,1.06] kg; p < 0.01; I²  = 56.9%) and trunk (0.56 [0.11,1.01] kg; p = 0.02; I²  = 42.8%) LBM or FFM. The PCOS subgroup with BMI ≥ 25 kg/m² had greater total LBM or FFM versus controls (1.58 [0.82,2.34] kg; p < 0.01; I²  = 64.0%) unlike the PCOS subgroup with BMI < 25 kg/m² (-0.45 [-1.94,1.05] kg; p = 0.53; I²  = 69.5%). Appendicular lean mass and muscle strength data were contradictory and described narratively, as meta-analyses were impossible. Women with PCOS have higher total and trunk lean tissue mass attributed to overweight/obesity, unlike hyperandrogenism or insulin resistance.

Uterine anomalies in cell proliferation, energy homeostasis and oxidative stress in PCOS hamsters, M. auratus: Therapeutic potentials of melatonin

AIMS

Polycystic ovarian syndrome (PCOS) is a reproductive, endocrine and metabolic disorder. Less is known about the mechanism of its effect on uterine function and therapeutic potential of melatonin. Our aim was to evaluate uterine dysfunction(s) in letrozole induced PCOS and its possible rectification by melatonin.

MAIN METHODS

Adult female golden hamsters were divided into groups of Control (C), Melatonin (M; 1 mg/kg b.w.), Letrozole (L; 3 mg/kg b.w.) and combination of Letrozole+Melatonin (L + M; 3 mg/kg b.w. + 1 mg/kg b.w.) which were treated for 40 days. Analysis of serum testosterone/estradiol/progesterone/leptin/insulin, uterine histomorphometry, immunohistochemistry for proliferation cell nuclear antigen (PCNA), homeostatic assessment model of insulin resistance (HOMA-IR), western blotting for PCNA, androgen receptor (AR), insulin receptor (InsR), glucose tansporter-4 (GLUT-4), nuclear factor-kappa B (NFκB), cyclooxygenase-2 (COX-2) and biochemical analysis of superoxide dismutase (SOD)/catalase/lipid peroxidation (LPO) were done.

KEY FINDINGS

Serum testosterone, leptin and insulin increased while uterine InsR/GLUT-4 expression decreased in L group indicating metabolic abnormalities. Endometrial hyperplasia, increased expression of PCNA and AR indicated abnormal proliferation in L compared to C. Increased uterine oxidative load (SOD/catalase/LPO) and inflammatory markers NFκB/COX-2 expression in L was responsible for high tissue oxidative stress and inflammation. M administration normalized all the above parameters suggesting its ameliorative effect in L + M group.

SIGNIFICANCE

We report PCOS induced uterine dysfunction in Mesocricetus auratus for the first time. M administration restores uterine functions modulating cellular dynamicity, metabolic status, decreased oxidative and inflammatory load in PCOS hamsters. Therefore, we suggest the therapeutic potential of M against PCOS led uterine abnormalities to restore female fertility.

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.

Influence of pretreatment of insulin on the phosphorylation of extracellular receptor kinase by gonadotropin-releasing hormone and gonadotropins in cultured human granulosa cells

OBJECTIVE

To investigate the influence of pretreatment of insulin on the phosphorylation of ERK1/2 by gonadotropin-releasing hormone (GnRH), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) in cultured human granulosa cells.

STUDY DESIGN

Human granulosa cells were collected from 20 women (age: 20-35 years) who underwent controlled ovarian hyperstimulation for in vitro fertilization and embryo transfer at Asan Medical Center (Seoul, South Korea). The presence of the receptors for insulin, GnRH, FSH, and LH in human granulosa cells was identified by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR). The granulosa cells were treated with 10 nM insulin or 10 nM GnRH for 5 min or 30 min and with 10 nM FSH or 10 nM LH for 24 h or 48 h. The cells were also pretreated with insulin for 30 min prior to treatment with GnRH, FSH, or LH. Western blot analysis was used to analyze ERK1/2 phosphorylation.

RESULTS

RT-PCR showed that the receptors for insulin, GnRH, FSH, and LH were expressed in human granulosa cells. Insulin, GnRH, FSH, and LH could activate ERK1/2 phosphorylation. Pretreatment with insulin inhibited ERK1/2 phosphorylation induced by GnRH and FSH while augmenting ERK1/2 phosphorylation induced by LH.

CONCLUSIONS

Insulin might have a negative effect on GnRH and FSH regulation by attenuating the action of GnRH and FSH in the phosphorylation of ERK1/2 in human granulosa cells. In contrast, insulin might have a positive effect on LH regulation by potentiating the action of LH in the phosphorylation of ERK1/2. Our results showed that insulin is clearly an important regulator of human reproductive function at the ovarian level.

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.

Assessment of Early Markers of Cardiovascular Risk in Polycystic Ovary Syndrome

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Transforming Growth Factor Beta 1 Alters Glucose Uptake but Not Insulin Signalling in Human Primary Myotubes From Women With and Without Polycystic Ovary Syndrome

Women with polycystic ovary syndrome (PCOS), commonly have profound skeletal muscle insulin resistance which can worsen other clinical features. The heterogeneity of the condition has made it challenging to identify the precise mechanisms that cause this insulin resistance. A possible explanation for the underlying insulin resistance may be the dysregulation of Transforming Growth Factor-beta (TGFβ) signalling. TGFβ signalling contributes to the remodelling of reproductive and hepatic tissues in women with PCOS. Given the systemic nature of TGFβ signalling and its role in skeletal muscle homeostasis, it may be possible that these adverse effects extend to other peripheral tissues. We aimed to determine if TGFβ1 could negatively regulate glucose uptake and insulin signalling in skeletal muscle of women with PCOS. We show that both myotubes from women with PCOS and healthy women displayed an increase in glucose uptake, independent of changes in insulin signalling, following short term (16 hr) TGFβ1 treatment. This increase occurred despite pro-fibrotic signalling increasing via SMAD3 and connective tissue growth factor in both groups following treatment with TGFβ1. Collectively, our findings show that short-term treatment with TGFβ1 does not appear to influence insulin signalling or promote insulin resistance in myotubes. These findings suggest that aberrant TGFβ signalling is unlikely to directly contribute to skeletal muscle insulin resistance in women with PCOS in the short term but does not rule out indirect or longer-term effects.

Pregnancy Outcomes of Women With Polycystic Ovary Syndrome for the First In Vitro Fertilization Treatment: A Retrospective Cohort Study With 7678 Patients

Background

The risk of adverse pregnancy outcomes is increased by having a polycystic ovary syndrome (PCOS) diagnosis. However, the confounders in previous studies preclude firm conclusions, and further studies are warranted.

Objectives

To investigate whether PCOS affects pregnancy outcomes and complications in infertile women undergoing their first in vitro fertilization (IVF) treatment, taking into account important confounders.

Methods

We performed a retrospective cohort study of 7,678 infertile women, including 666 women with PCOS and 7,012 controls undergoing their first IVF treatment at a private fertility center from January 2010 to December 2017. Our main outcome was the impact of PCOS on adverse pregnancy outcomes (miscarriage, preterm delivery, pregnancy-induced hypertension) and pregnancy outcomes (live birth rate, clinical pregnancy rate, implantation rate). PCOS effects were summarized by adjusted odds ratios (aORs) with 95% confidence intervals (CIs) after controlling for maternal characteristics.

Results

After adjusting for differences in maternal age, BMI, infertility duration, total dose of gonadotropin, serum E2 and endometrial thickness on the day of hCG trigger, number of fertilized occytes, number of embryos transferred, embryo type (cleavage-stage embryo or blastocyst) and quality, women with PCOS had an increased risk of developing unfavorable pregnancy complications, including miscarriage (aOR 1.629, 95% CI 1.240-2.141), very preterm delivery (< 32 weeks) (aOR 2.072, 95% CI 1.133-3.791). For pregnancy outcomes, PCOS was associated with higher clinical pregnancy rate (aOR 1.248, 95% CI 1.038-1.501) and implantation rate (aOR 1.238, 95% CI 1.030-1.489) after adjusting for the above-mentioned confounders.

Conclusions

Women with PCOS are at increased risk of adverse pregnancy outcomes after adjusting for differences in maternal characteristics. These women may need more frequent medical consultants and management during pregnancy and parturition.

The Relationship Between Polycystic Ovarian Syndrome, Periodontal Disease, and Osteoporosis

Polycystic ovarian syndrome (PCOS) is the most common endocrine disorder to affect women in their reproductive years. There has been growing concern that women with PCOS may suffer from long-term metabolic consequences due to the high degree of insulin resistance that is often present in PCOS. However, few longitudinal studies exist in this area and there is a paucity of data on whether women with PCOS are at risk of other chronic diseases as they age. Specifically, current evidence suggests that reproductive-age women with PCOS may be at increased risk for both osteoporosis and periodontal disease (PD)-both these chronic diseases can have serious implications for health and quality of life. However, few studies have addressed how risk factors for osteoporosis and PD may be altered by aging in PCOS. The PCOS phenotype of women beyond reproductive years is poorly understood, and it is not known whether the metabolic profile of older women with PCOS results in an increased risk of osteoporosis and PD. The objective of this review is to discuss the relationships between PCOS, osteoporosis, and PD, and how these relationships could be impacted during aging. The long-term goal of this review is to provide direction for future research that is needed to more clearly elucidate these relationships and eventually provide a basis for evidence-based health recommendations.

Altered circadian clock as a novel therapeutic target for constant darkness-induced insulin resistance and hyperandrogenism of polycystic ovary syndrome

The mechanisms underlying metabolic and reproductive dysfunction caused by arrhythmic circadian clock and their involvement in polycystic ovary syndrome (PCOS) are not understood. Here, we addressed this issue using rats with constant light or darkness exposure for 8 weeks and human leukocytes and serum of PCOS and non-PCOS patients. Additionally, we utilized HepG2 cells and KGN cells to verify the molecular mechanisms. The arrhythmic expressions of circadian clock genes due to constant darkness induced the metabolic and reproductive hallmarks of PCOS in rats. After exposure to constant darkness, decreased brain and muscle ARNT-like protein 1 (BMAL1) promoted insulin resistance via glucose transporter 4 (GLUT4), and decreased period (PER) 1 and PER2 promoted androgen excess via insulin-like growth factor-binding protein 4 (IGFBP4) and sex hormone binding globulin (SHBG) in the liver. Hyperinsulinemia and hyperandrogenism shared a bidirectional link promoting aberrant expression of circadian genes and inducing apoptosis of ovarian granulosa cells. Notably, the altered expressions of circadian clock genes in darkness-treated rats matched those of PCOS patients. Furthermore, melatonin treatment relieved the hyperinsulinemia and hyperandrogenism of darkness-treated rats via BMAL1, PER1, and PER2. Restoring normal light/dark exposure for 2 weeks reversed these conditions via BMAL1. In conclusion, our findings elucidated the critical function of circadian clock genes, especially BMAL1, PER1, and PER2 in PCOS, which might aid the development of feasible preventive and therapeutic strategies for PCOS in women with biorhythm disorder.

Decreased brain and muscle ARNT-like protein 1 expression mediated the contribution of hyperandrogenism to insulin resistance in polycystic ovary syndrome

BACKGROUND

The interface between environmental risk factors and genetic factors could contribute to the pathogenesis of hyperandrogenism and insulin resistance in polycystic ovary syndrome (PCOS); however, the underlying complex mechanism remains to be elucidated.

METHODS

We used dehydroepiandrosterone (DHEA)-induced PCOS-like rat model to measure circadian clock genes and insulin resistance-related genes. Additionally, we performed in vitro experiments in mature adipocytes to verify the molecular mechanisms.

RESULTS

DHEA-induced PCOS-like rats exhibited insulin resistance and arrhythmic expression of circadian clock genes in the liver and adipose tissues, particularly showing decreased brain and muscle ARNT-like protein 1 (BMAL1) expression. In addition, hyperandrogenism gave rise to negative regulation of BMAL1 expression to nicotinamide phosphoribosyltransferase and sirtuin 1, which further inhibited downstream glucose transporter type 4, leading to insulin resistance in mature adipocytes, which was consistent with our previous results in HepG2 cells.

CONCLUSIONS

Decreased BMAL1 expression in the liver and adipose played a potentially novel role in the contribution of hyperandrogenism to insulin resistance, which might be a possible mechanism accounting for the pathogenesis of PCOS.

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.

Polycystic Ovary Syndrome: Novel and Hub lncRNAs in the Insulin Resistance-Associated lncRNA-mRNA Network

Polycystic ovary syndrome (PCOS) is a common metabolic and reproductive disorder with an increasing risk for type 2 diabetes. Insulin resistance is a common feature of women with PCOS, but the underlying molecular mechanism remains unclear. This study aimed to screen critical long non-coding RNAs (lncRNAs) that might play pivotal roles in insulin resistance, which could provide candidate biomarkers and potential therapeutic targets for PCOS. Gene expression profiles of the skeletal muscle in patients with PCOS accompanied by insulin resistance and healthy patients were obtained from the publicly available Gene Expression Omnibus (GEO) database. A global triple network including RNA-binding protein, mRNA, and lncRNAs was constructed based on the data from starBase. Then, we extracted an insulin resistance-associated lncRNA–mRNA network (IRLMN) by integrating the data from starBase and GEO. We also performed a weighted gene co-expression network analysis (WGCNA) on the differentially expressed genes between the women with and without PCOS, to identify hub lncRNAs. Additionally, the findings of key lncRNAs were examined in an independent GEO dataset. The expression level of lncRNA RP11-151A6.4 in ovarian granulosa cells was increased in patients with PCOS compared with that in control women. Levels were also increased in PCOS patients with higher BMI, hyperinsulinemia, and higher HOMA-IR values. As a result, RP11-151A6.4 was identified as a hub lncRNA based on IRLMN and WGCNA and was highly expressed in ovarian granulosa cells, skeletal muscle, and subcutaneous and omental adipose tissues of patients with insulin resistance. This study showed the differences between lncRNA and mRNA profiles from healthy women and women with PCOS and insulin resistance. Here, we demonstrated that RP11-151A6.4 might play a vital role in insulin resistance, androgen excess, and adipose dysfunction in patients with PCOS. Further study concerning RP11-151A6.4 could elucidate the underlying mechanisms of insulin resistance.

DNA methylation in the pathogenesis of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is the leading endocrine and metabolic disorder in premenopausal women characterized by hyperandrogenism and abnormal development of ovarian follicles. To date, the PCOS etiology remains unclear and has been related to insulin resistance, obesity, type 2 diabetes mellitus, cardiovascular disease and infertility, among other morbidities. Substantial evidence illustrates the impact of genetic, intrauterine and environmental factors on the PCOS etiology. Lately, epigenetic factors have garnered considerable attention in the pathogenesis of PCOS considering that changes in the content of DNA methylation, histone acetylation and noncoding RNAs have been reported in various tissues of women with this disease. DNA methylation is changed in the peripheral and umbilical cord blood, as well as in ovarian and adipose tissue of women with PCOS, suggesting the involvement of this epigenetic modification in the pathogenesis of the disease. Perhaps, these defects in DNA methylation promote the deregulation of genes involved in inflammation, hormone synthesis and signaling and glucose and lipid metabolism. Research on the role of DNA methylation in the pathogenesis of PCOS is just beginning, and several issues await investigation. This review aims to provide an overview of current research focused on DNA methylation and PCOS, as well as discuss the perspectives regarding this topic.

Heat therapy improves glucose tolerance and adipose tissue insulin signaling in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is associated with high rates of obesity and metabolic dysfunction. Repeated passive heat exposure (termed heat therapy) is a novel lifestyle intervention for improving health in obese women with PCOS. The purpose of this study was to examine changes in metabolic function in obese women with PCOS following heat therapy. Eighteen age- and BMI-matched obese women with PCOS (age: 27 ± 1 yr, BMI: 41.3 ± 1.1 kg/m^-2) were assigned to heat therapy (HT) or time control (CON). HT participants underwent 30 one-hour hot tub sessions over 8-10 wk, while CON participants completed all testing but did not undergo heat therapy. Before (Pre), at the mid-point (Mid), and following (Post) 8-10 wk of heat therapy, metabolic health was assessed using a 2-h oral glucose tolerance test, a subcutaneous abdominal fat biopsy (Pre-Post only), and other blood markers relating to metabolic function. HT participants exhibited improved fasting glucose (Pre: 105 ± 3, Post: 89 ± 5mg/dl; P = 0.001), glucose area under the curve (AUC) (Pre: 18,698 ± 1,045, Post: 16,987 ± 1,017 mg·dl^-1·min^-1; P = 0.028) and insulin AUC (Pre: 126,924 ± 11,730, Post: 91,233 ± 14,429 IU l^-1·min^-1; P = 0.012). Adipocyte insulin signaling (p-AKT at Ser-473 with 1.2 nM insulin) increased in HT (Pre: 0.29 ± 0.14, Post: 0.93 ± 0.29 AU; P = 0.021). Additionally, serum testosterone declined in HT participants (Pre: 51 ± 7, Post: 34 ± 4 ng/dl; P = 0.033). No parameters changed over time in CON, and no change in BMI was observed in either group. HT substantially improved metabolic risk profile in obese women with PCOS. HT also reduced androgen excess and may improve PCOS symptomology.

Molecular Mechanisms in Skeletal Muscle Underlying Insulin Resistance in Women Who Are Lean With Polycystic Ovary Syndrome

CONTEXT

Skeletal muscle molecular mechanisms underlying insulin resistance in women with polycystic ovary syndrome (PCOS) are poorly understood.

OBJECTIVE

To provide insight into mechanisms regulating skeletal muscle insulin resistance in women who are lean with PCOS.

PARTICIPANTS AND METHODS

A hyperinsulinemic-euglycemic clamp with skeletal muscle biopsies was performed. Thirteen women who are lean who have hyperandrogenism and PCOS and seven age- and body mass index-matched healthy control subjects were enrolled. Skeletal muscle protein expression and phosphorylation were analyzed by Western blotting and intramuscular lipid content was measured by thin-layer chromatography.

RESULTS

Women with PCOS had 25% lower whole-body insulin sensitivity and 40% lower plasma adiponectin concentration than in control subjects. Intramuscular triacylglycerol, sn-1.3 diacylglycerol, and ceramide contents in skeletal muscle were higher (40%, 50%, and 300%, respectively) in women with PCOS than in control subjects. Activation of insulin signaling did not differ between groups. In women with PCOS, the insulin-stimulated glucose oxidation was reduced and insulin-stimulated dephosphorylation of pyruvate dehydrogenase (PDH) Ser293 was absent. AMP-activated protein kinase (AMPK) α2 protein expression and basal Thr172 phosphorylation were 45% and 50% lower in women with PCOS than in control subjects, respectively.

CONCLUSIONS

Whole-body insulin resistance in women who are lean who have hyperandrogenism and PCOS was not related to changes in the proximal part of the insulin signaling cascade in skeletal muscle despite lipid accumulation. Rather, reduced insulin sensitivity was potentially related to plasma adiponectin levels playing a modulating role in human skeletal muscle via AMPK. Furthermore, abnormal PDH regulation may contribute to reduced whole-body metabolic flexibility and thereby insulin resistance.

Makorin 1 is required for Drosophila oogenesis by regulating insulin/Tor signaling

Reproduction is a process that is extremely sensitive to changes in nutritional status. The nutritional control of oogenesis via insulin signaling has been reported; however, the mechanism underlying its sensitivity and tissue specificity has not been elucidated. Here, we determined that Drosophila Makorin RING finger protein 1 gene (Mkrn1) functions in the metabolic regulation of oogenesis. Mkrn1 was endogenously expressed at high levels in ovaries and Mkrn1 knockout resulted in female sterility. Mkrn1-null egg chambers were previtellogenic without egg production. FLP-FRT mosaic analysis revealed that Mkrn1 is essential in germline cells, but not follicle cells, for ovarian function. As well, AKT phosphorylation via insulin signaling was greatly reduced in the germline cells, but not the follicle cells, of the mutant clones in the ovaries. Furthermore, protein-rich diet elevated Mkrn1 protein levels, without increased mRNA levels. The p-AKT and p-S6K levels, downstream targets of insulin/Tor signaling, were significantly increased by a nutrient-rich diet in wild-type ovaries whereas those were low in Mkrn1^exS compared to wild-type ovaries. Taken together, our results suggest that nutrient availability upregulates the Mkrn1 protein, which acts as a positive regulator of insulin signaling to confer sensitivity and tissue specificity in the ovaries for proper oogenesis based on nutritional status.

Implications and Future Perspectives of AGEs in PCOS Pathophysiology

Human, animal, and in vitro studies provide evidence that advanced glycation end-products (AGEs) may contribute to the pathogenesis of polycystic ovary syndrome (PCOS) and its metabolic and reproductive consequences. AGEs are able to induce, via activation of key intracellular signaling pathways, the generation of oxidative stress and proinflammatory cytokines, thus contributing to the adverse health impact of PCOS. This review presents the implications of AGEs in several disease pathophysiologies, including PCOS, as well as the cellular and systemic effects of AGEs on insulin resistance (IR), hyperandrogenemia, endoplasmic reticulum (ER) stress, hypoxia, and ovarian function. The gaps in our knowledge will serve as launching pad for future developments ranging from dietary and lifestyle changes to pharmaceutical interventions aiming at potential applications in women with PCOS.

Ethnicity, obesity and the prevalence of impaired glucose tolerance and type 2 diabetes in PCOS: a systematic review and meta-regression

BACKGROUND

Our prior meta-analyses demonstrated an increased prevalence of impaired glucose tolerance (IGT) and type 2 diabetes mellitus (T2DM) with polycystic ovary syndrome (PCOS), but with substantial clinical heterogeneity.

OBJECTIVE AND RATIONALE

We aimed to update our previous review to quantify the prevalence of IGT and T2DM in PCOS with only quality studies (good and fair quality). We also aimed to examine the contribution of parameters including ethnicity, obesity and method of diagnosing T2DM in explaining the observed heterogeneity in IGT and T2DM prevalence in PCOS.

SEARCH METHODS

We conducted a literature search (MEDLINE, CINAHL, EMBASE, clinical trial registries and hand-searching) up to June 2016 to identify studies reporting the prevalence of dysglycemia (IGT and T2DM) in women with and without PCOS. We included studies where women with PCOS (defined according to original National Institute of Health) were compared to women without PCOS for the end-points of the prevalence of IGT or T2DM. We excluded case reports, case series, editorials, and narrative reviews. Studies where PCOS was diagnosed by self-report, or where IGT or T2DM were measured by fasting glucose, only were excluded. We assessed the methodological quality of the included studies using a priori criteria based on the Newcastle-Ottawa Scaling (NOS) for non-randomized studies. Data are presented as odds ratio (OR) (95% CI) with random-effects meta-analysis by Mantel-Haenszel methods. We assessed the contribution of demographic and clinical factors to heterogeneity using subgroup and meta-regression analysis.

OUTCOMES

We reviewed 4530 studies and included 40 eligible studies in the final analysis. On meta-analysis of quality studies, women with PCOS had an increased prevalence of IGT (OR = 3.26, 95% CI: 2.17-4.90) and T2DM (OR = 2.87, 95% CI: 1.44-5.72), which differed by ethnicity (for IGT, Asia: 5-fold, the Americas: 4-fold and Europe: 3-fold), was higher with obesity, and doubled among studies using self-report or administrative data for diagnosing diabetes. The ethnicity-related difference retained its significance for Asia and Europe in BMI-matched subgroups. Clear contributors to heterogeneity did not emerge in meta-regression.

WIDER IMPLICATIONS

Our findings underscore the importance of PCOS as a cause of dysglycemia with a higher prevalence of IGT and T2DM. They support the relevance of ethnicity and obesity and emphasize the need for accurate diagnostic methods for diabetes.

PROSPERO REGISTRATION NUMBER

CRD42017056524.

Acupuncture or metformin to improve insulin resistance in women with polycystic ovary syndrome: study protocol of a combined multinational cross sectional case-control study and a randomised controlled trial

INTRODUCTION

Polycystic ovary syndrome (PCOS) is linked to hyperinsulinemia and insulin resistance with dysfunctional glucose metabolism. Pilot studies suggests that acupuncture treatment with combined manual and low-frequency electrical stimulation (electroacupuncture (EA)) of the needles decrease circulating glycated haemoglobulin (HbA1c) and homeostatic model assessment-insulin resistance. Therefore, we here aim to investigate if acupuncture treatment or metformin together with lifestyle or lifestyle management alone improves insulin sensitivity and related symptoms in overweight/obese women with PCOS.

METHODS AND ANALYSIS

This is a two-centre multinational (Sweden and China), cross-sectional case-control study combined with an open-labelled randomised controlled trial (RCT). Participants are randomised to one of three groups: (1) EA 2-3 times/week during 4 months+lifestyle management; (2) metformin, 500 mg, three/day during 4 months+lifestyle management; or (3) lifestyle management alone. The primary outcome measure in the RCT is changes in HbA1C. A total of 123 obese overweight women with PCOS will be enrolled and randomised into one of the three groups with a target power of at least 80% and 5% significance level based on two-sided tests.

ETHICS AND DISSEMINATION

The study has been approved by the Regional Ethical Review Board of Stockholm and of Peking University Third Hospital, China. Primary outcome data of the RCT will be published in a relevant journal together with supporting secondary outcome measurements. Further, outcome measurements will be published in separate papers as well as case-control data.

EXPECTED RESULTS

We anticipate that EA and metformin, both with lifestyle management, are equally effective and superior to lifestyle management alone for improvement of glycaemic control.

TRIAL REGISTRATION NUMBERS

NCT02647827 and EudraCT2015-004250-18.

Metabolomics of Dynamic Changes in Insulin Resistance Before and After Exercise in PCOS

Background: Plasma elevated levels of branched chain amino acids (BCAA) and aromatic amino acids (AAA) have been associated with obesity and insulin resistance, but their relationship to stimulated insulin resistance (IR) in PCOS and in response to exercise is unknown. Indeed, it is unknown whether the mechanism of IR in PCOS is mediated through changes in the metabolome. Methods: Twelve women with polycystic ovary syndrome (PCOS) and ten age and body mass index matched controls completed an 8 week supervised exercise program at 60% maximal oxygen consumption. Before and after the exercise program, all participants underwent maximal IR stimulation with intralipid infusions followed by insulin sensitivity (IS) measurement by hyperinsulinaemic euglycaemic clamps. Amino acid profiles and metabolites were taken at baseline and at maximal insulin resistance stimulation before and after the exercise program. Results: At baseline, PCOS subjects showed increased leucine/isoleucine, glutamate, methionine, ornithine, phenylalanine, tyrosine and proline (p < 0.05) that, following exercise, did not differ from controls. While compering within the groups, no significant changes in the amino acid levels before and after exercise were observed. Exercise improved VO2 max (p < 0.01) but did not alter weight. Amino acid profiles were unaffected by an acute increase in IR induced by the lipid infusion. IS was lower in PCOS (p < 0.001) and was further decreased by the lipid infusion in both PCOS and controls. Although, exercise improved IS in both PCOS and in controls, the IS remained compromised in PCOS. Conclusion: The baseline amino acid profile in PCOS reflected that seen in obese subjects and differed to controls. After exercise, and despite no change in weight in either group, there were no differences in the amino acid profile between PCOS and controls. This shows that exercise may normalize the amino acid metabolome, irrespective of weight. ISRCTN number: ISRCTN42448814.

Transcriptional and Epigenetic Changes Influencing Skeletal Muscle Metabolism in Women With Polycystic Ovary Syndrome

CONTEXT

Insulin resistance in skeletal muscle is a major risk factor for the development of type 2 diabetes in women with polycystic ovary syndrome (PCOS). Despite this, the mechanisms underlying insulin resistance in PCOS are largely unknown.

OBJECTIVE

To investigate the genome-wide DNA methylation and gene expression patterns in skeletal muscle from women with PCOS and controls and relate them to phenotypic variations.

DESIGN/PARTICIPANTS

In a case-control study, skeletal muscle biopsies from women with PCOS (n = 17) and age-, weight-, and body mass index‒matched controls (n = 14) were analyzed by array-based DNA methylation and mRNA expression profiling.

RESULTS

Eighty-five unique transcripts were differentially expressed in muscle from women with PCOS vs controls, including DYRK1A, SYNPO2, SCP2, and NAMPT. Furthermore, women with PCOS had reduced expression of genes involved in immune system pathways. Two CpG sites showed differential DNA methylation after correction for multiple testing. However, an mRNA expression of ∼30% of the differentially expressed genes correlated with DNA methylation levels of CpG sites in or near the gene. Functional follow-up studies demonstrated that KLF10 is under transcriptional control of insulin, where insulin promotes glycogen accumulation in myotubes of human muscle cells. Testosterone downregulates the expression levels of COL1A1 and MAP2K6.

CONCLUSION

PCOS is associated with aberrant skeletal muscle gene expression with dysregulated pathways. Furthermore, we identified specific changes in muscle DNA methylation that may affect gene expression. This study showed that women with PCOS have epigenetic and transcriptional changes in skeletal muscle that, in part, can explain the metabolic abnormalities seen in these women.

Polycystic Ovary Syndrome: Implication for Drug Metabolism on Assisted Reproductive Techniques-A Literature Review

Polycystic ovary syndrome (PCOS) affects 6-10% of women and could be considered one of the most common endocrine alterations in women of reproductive age. The syndrome is characterized by several hormonal and metabolic alterations, including insulin resistance and hyperandrogenism, which play a severe detrimental role in the patient's fertility. We aimed to offer an overview about drug metabolism in the PCOS population. Nevertheless, we did not find any study that directly compared drug metabolism between PCOS and healthy women. We therefore decided to summarize briefly how hormonal and insulin sensitizer drugs act differently in healthy and PCOS women, who show altered steroidogenesis by theca cells and metabolic imbalance, focusing especially on assisted reproductive techniques. To date, data about drug metabolism in the PCOS population appears to be extremely limited. This important gap could have significant implications for therapeutic approaches and future perspectives: the dosage of drugs commonly used for the treatment of PCOS women should be tailored according to each patient's characteristics; we should implement new clinical trials in order to identify the best pharmacologic strategy for PCOS patients undergoing in vitro fertilization (IVF); it would be advisable to create an international expert panel to investigate the drug metabolism in the PCOS population.

Ovarian and Extra-Ovarian Mediators in the Development of Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a heterogeneous endocrine disorder affecting women of reproductive age. The origin of PCOS is still not clear and appears to be a function of gene x environment interactions. This review addresses the current knowledge of the genetic and developmental contributions to the etiology of PCOS, the ovarian and extra-ovarian mediators of PCOS and the gaps and key challenges that need to be addressed in the diagnosis, treatment and prevention of PCOS.