Is polycystic ovary syndrome a sexual conflict? A review

X centromeric drive may explain the prevalence of polycystic ovary syndrome and other conditions: Genomic structure of the human X chromosome pericentromeric region is consistent with meiotic drive associated with PCOS and other conditions

X chromosome centromeric drive may explain the prevalence of polycystic ovary syndrome and contribute to oocyte aneuploidy, menopause, and other conditions. The mammalian X chromosome may be vulnerable to meiotic drive because of X inactivation in the female germline. The human X pericentromeric region contains genes potentially involved in meiotic mechanisms, including multiple SPIN1 and ZXDC paralogs. This is consistent with a multigenic drive system comprising differential modification of the active and inactive X chromosome centromeres in female primordial germ cells and preferential segregation of the previously inactivated X chromosome centromere to the polar body at meiosis I. The drive mechanism may explain differences in X chromosome regulation in the female germlines of the human and mouse and, based on the functions encoded by the genes in the region, the transmission of X pericentromeric genetic or epigenetic variants to progeny could contribute to preeclampsia, autism, and differences in sexual differentiation.

Effect of Consultation Number on the Assessment and Treatment of Polycystic Ovary Syndrome

Background

The basic medical education stage is not enough to support physicians to fully diagnose and evaluate polycystic ovary syndrome (PCOS). The study aims to discover the difference in treatment choice between participants with different annual consultation number of PCOS, to promote lifelong learning, and drive balanced development within healthcare.

Methods

This is a multicenter cross-sectional survey. Participants' basic information, knowledge of PCOS and treatment options were collected online. According to the annual consultation number of patients with PCOS, physicians were divided into three groups: 0-50 people/yr, 50-200 people/yr, and >200 people/yr, and the results were derived from χ2 test, Fisher exact test, and multivariate logistic regression analysis.

Results

The study analyzed 1689 questionnaires, and 1206 physicians (71.4%) received less than 50 women per year, 388 physicians (30.0%) with an annual number of 50-200 women, and 95 physicians (5.6%) with patient turnover for more than 200 people. Reproductive endocrinologists generally have higher access to the clinic. As the number of visits increases, more and more physicians would perceive patients as more likely to have abnormal blood glucose and heavy weight. Physicians with large numbers of consultations are more likely to use Asian or Chinese standards to assess obesity. The multivariate analysis involved variables such as age, hospital level, specialty, and patient turnover annually, and more young doctors actively assessed lipid profile (odds ratio (OR) 1.56, 95% confidence interval (CI) (1.16, 2.16)), and primary hospitals (OR 0.65 CI (0.44, 0.89)) chose OGTT for blood glucose assessment less than tertiary hospitals. Physicians in secondary hospitals are more aggressive in evaluating androgens.

Conclusion

Our survey found differences in endocrine assessment, metabolic screening, and treatment in PCOS women in terms of the number of obstetrician-gynecologists who received different patient consultation numbers. The importance of continuing education for physicians is emphasized, to promote lifelong learning.

Pathophysiological Effects of Contemporary Lifestyle on Evolutionary-Conserved Survival Mechanisms in Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is increasingly being characterized as an evolutionary mismatch disorder that presents with a complex mixture of metabolic and endocrine symptoms. The Evolutionary Model proposes that PCOS arises from a collection of inherited polymorphisms that have been consistently demonstrated in a variety of ethnic groups and races. In utero developmental programming of susceptible genomic variants are thought to predispose the offspring to develop PCOS. Postnatal exposure to lifestyle and environmental risk factors results in epigenetic activation of developmentally programmed genes and disturbance of the hallmarks of health. The resulting pathophysiological changes represent the consequences of poor-quality diet, sedentary behaviour, endocrine disrupting chemicals, stress, circadian disruption, and other lifestyle factors. Emerging evidence suggests that lifestyle-induced gastrointestinal dysbiosis plays a central role in the pathogenesis of PCOS. Lifestyle and environmental exposures initiate changes that result in disturbance of the gastrointestinal microbiome (dysbiosis), immune dysregulation (chronic inflammation), altered metabolism (insulin resistance), endocrine and reproductive imbalance (hyperandrogenism), and central nervous system dysfunction (neuroendocrine and autonomic nervous system). PCOS can be a progressive metabolic condition that leads to obesity, gestational diabetes, type two diabetes, metabolic-associated fatty liver disease, metabolic syndrome, cardiovascular disease, and cancer. This review explores the mechanisms that underpin the evolutionary mismatch between ancient survival pathways and contemporary lifestyle factors involved in the pathogenesis and pathophysiology of PCOS.

Polycystic Ovary Syndrome: An Evolutionary Adaptation to Lifestyle and the Environment

Polycystic ovary syndrome (PCOS) is increasingly recognized as a complex metabolic disorder that manifests in genetically susceptible women following a range of negative exposures to nutritional and environmental factors related to contemporary lifestyle. The hypothesis that PCOS phenotypes are derived from a mismatch between ancient genetic survival mechanisms and modern lifestyle practices is supported by a diversity of research findings. The proposed evolutionary model of the pathogenesis of PCOS incorporates evidence related to evolutionary theory, genetic studies, in utero developmental epigenetic programming, transgenerational inheritance, metabolic features including insulin resistance, obesity and the apparent paradox of lean phenotypes, reproductive effects and subfertility, the impact of the microbiome and dysbiosis, endocrine-disrupting chemical exposure, and the influence of lifestyle factors such as poor-quality diet and physical inactivity. Based on these premises, the diverse lines of research are synthesized into a composite evolutionary model of the pathogenesis of PCOS. It is hoped that this model will assist clinicians and patients to understand the importance of lifestyle interventions in the prevention and management of PCOS and provide a conceptual framework for future research. It is appreciated that this theory represents a synthesis of the current evidence and that it is expected to evolve and change over time.

Conceptualization of functional single nucleotide polymorphisms of polycystic ovarian syndrome genes: an in silico approach

PURPOSE

Polycystic ovarian syndrome (PCOS) is a multi-faceted endocrinopathy frequently observed in reproductive-aged females, causing infertility. Cumulative evidence revealed that genetic and epigenetic variations, along with environmental factors, were linked with PCOS. Deciphering the molecular pathways of PCOS is quite complicated due to the availability of limited molecular information. Hence, to explore the influence of genetic variations in PCOS, we mapped the GWAS genes and performed a computational analysis to identify the SNPs and their impact on the coding and non-coding sequences.

METHODS

The causative genes of PCOS were searched using the GWAS catalog, and pathway analysis was performed using ClueGO. SNPs were extracted using an Ensembl genome browser, and missense variants were shortlisted. Further, the native and mutant forms of the deleterious SNPs were modeled using I-TASSER, Swiss-PdbViewer, and PyMOL. MirSNP, PolymiRTS, miRNASNP3, and SNP2TFBS, SNPInspector databases were used to find SNPs in the miRNA binding site and transcription factor binding site (TFBS), respectively. EnhancerDB and HaploReg were used to characterize enhancer SNPs. Linkage Disequilibrium (LD) analysis was performed using LDlink.

RESULTS

25 PCOS genes showed interaction with 18 pathways. 7 SNPs were predicted to be deleterious using different pathogenicity predictions. 4 SNPs were found in the miRNA target site, TFBS, and enhancer sites and were in LD with reported PCOS GWAS SNPs.

CONCLUSION

Computational analysis of SNPs residing in PCOS genes may provide insight into complex molecular interactions among genes involved in PCOS pathophysiology. It may also aid in determining the causal variants and consequently contributing to predicting disease strategies.

The evolutionary biology of endometriosis

We provide the first analysis and synthesis of the evolutionary and mechanistic bases for risk of endometriosis in humans, structured around Niko Tinbergen's four questions about phenotypes: phylogenetic history, development, mechanism and adaptive significance. Endometriosis, which is characterized by the proliferation of endometrial tissue outside of the uterus, has its phylogenetic roots in the evolution of three causally linked traits: (1) highly invasive placentation, (2) spontaneous rather than implantation-driven endometrial decidualization and (3) frequent extensive estrogen-driven endometrial proliferation and inflammation, followed by heavy menstrual bleeding. Endometriosis is potentiated by these traits and appears to be driven, proximately, by relatively low levels of prenatal and postnatal testosterone. Testosterone affects the developing hypothalamic-pituitary-ovarian (HPO) axis, and at low levels, it can result in an altered trajectory of reproductive and physiological phenotypes that in extreme cases can mediate the symptoms of endometriosis. Polycystic ovary syndrome, by contrast, is known from previous work to be caused primarily by high prenatal and postnatal testosterone, and it demonstrates a set of phenotypes opposite to those found in endometriosis. The hypothesis that endometriosis risk is driven by low prenatal testosterone, and involves extreme expression of some reproductive phenotypes, is supported by a suite of evidence from genetics, development, endocrinology, morphology and life history. The hypothesis also provides insights into why these two diametric, fitness-reducing disorders are maintained at such high frequencies in human populations. Finally, the hypotheses described and evaluated here lead to numerous testable predictions and have direct implications for the treatment and study of endometriosis. Lay summary: Endometriosis is caused by endometrial tissue outside of the uterus. We explain why and how humans are vulnerable to this disease, and new perspectives on understanding and treating it. Endometriosis shows evidence of being caused in part by relatively low testosterone during fetal development, that 'programs' female reproductive development. By contrast, polycystic ovary syndrome is associated with relatively high testosterone in prenatal development. These two disorders can thus be seen as 'opposite' to one another in their major causes and correlates. Important new insights regarding diagnosis, study and treatment of endometriosis follow from these considerations.

FSH for the Treatment of Male Infertility

Follicle-stimulating hormone (FSH) supports spermatogenesis acting via its receptor (FSHR), which activates trophic effects in gonadal Sertoli cells. These pathways are targeted by hormonal drugs used for clinical treatment of infertile men, mainly belonging to sub-groups defined as hypogonadotropic hypogonadism or idiopathic infertility. While, in the first case, fertility may be efficiently restored by specific treatments, such as pulsatile gonadotropin releasing hormone (GnRH) or choriogonadotropin (hCG) alone or in combination with FSH, less is known about the efficacy of FSH in supporting the treatment of male idiopathic infertility. This review focuses on the role of FSH in the clinical approach to male reproduction, addressing the state-of-the-art from the little data available and discussing the pharmacological evidence. New compounds, such as allosteric ligands, dually active, chimeric gonadotropins and immunoglobulins, may represent interesting avenues for future personalized, pharmacological approaches to male infertility.

Association analysis between the tag single nucleotide polymorphisms of DENND1A and the risk of polycystic ovary syndrome in Chinese Han women

Background

The DENND1A gene is one of the most important sites associated with polycystic ovary syndrome (PCOS). We attempted to analyze the correlation between five single nucleotide polymorphisms (SNPs) in the DENND1A gene and the development of PCOS.

Methods

A total of 346 PCOS patients and 225 normal ovulatory women were involved in the case-control study. Clinical variables and hormones were recorded. According to the Hap Map database, five tagging SNPs (rs2479106, rs2768819, rs2670139, rs2536951 and rs2479102) in the DENND1A gene were identified. The TaqMan probe and the PCR–RFLP (restriction fragment length polymorphism) methods were used for revealing these genotypes. TaqMan Genotype Software was used to analyze the alleles of the five SNPs.

Results

Linkage disequilibrium and the gene frequency analysis demonstrated that the CCGGG haplotype might increase the risk of PCOS (P = 0.038, OR = 1.89, 95% CI = 1.027–3.481). Significant differences were found in genotypic and allelic distributions at the rs2536951 and rs2479102 loci between PCOS women and controls (P <  0.001). The LH levels and LH/FSH ratios were higher in PCOS patients than in the control group. A detailed analysis revealed that for the rs2479106 locus, these two values were significantly different in the control subjects who had AA, AG and GG genotypes (P = 0.013 and P = 0.007, respectively), and for the rs2468819 locus, these two values were significantly different among the PCOS patients with AA, AG and GG genotypes (P = 0.013 and 0.002, respectively).

Conclusions

The tagging SNPs rs2479106 and rs2468819 in the DENND1A gene are associated with PCOS in the Chinese population, whereas rs2670139, rs2536951 and rs2479102 are not correlated with PCOS in the same population.

Is polycystic ovary syndrome a 20th Century phenomenon?

Polycystic ovary syndrome (PCOS) affects around 10% of women of reproductive age and is most common in developed countries. The aetiology of PCOS is not completely understood. Current evidence suggests that the syndrome results from a genetic predisposition interacting with developmental events during fetal or perinatal life that together increase susceptibility in some individuals. This implies that environmental factors influence the initiation of PCOS in the fetus or infant, either directly or via the mother. PCOS is often considered to be an ancient disorder but there is no direct proof of this in the medical or historic record. One of the cardinal features, polycystic ovaries, was first described only in the early 1900s, despite reports of many thousands of autopsies recorded earlier. This conundrum could be explained by postulating that polycystic ovaries were rare before the 1900s and have become more common over the last 100 years. The hypothesis that PCOS is a syndrome of the 20th Century would eliminate the need to explain the paradox of why there exists a genetic predisposition to subfertility syndrome.

Follicle Stimulating Hormone Receptor (FSHR) Polymorphisms and Polycystic Ovary Syndrome (PCOS)

Polycystic ovary syndrome (PCOS) is the commonest endocrine abnormality in women of reproductive age typically presenting with chronic oligo- or anovulation, clinical, or biochemical hyperandrogenism and polycystic ovarian morphology (PCOM). Restoring mono-ovulation is the ultimate goal of ovulation induction and most women do respond to ovulation inducing agents causing their Follicle-stimulating hormone (FSH) levels to rise. Familial clustering and the results from twin studies strongly support an underlying genetic basis for PCOS. Recent Genome wide association studies (GWAS) have identified several genetic variants being genome wide significantly associated with PCOS. Amongst those are variants in or near the Luteinizing hormone (LH) and FSH receptor genes as well as a variant in the FSH-β gene. The aim of this review is to summarize the available evidence as to whether single nucleotide polymorphisms are able to modify the PCOS phenotype or whether they constitute a risk factor for the syndrome. Data on the role of FSHR polymorphisms in PCOS are conflicting. It seems that in large Chinese studies FSHR polymorphisms are not associated with either PCOS risk or with PCOS treatment outcome. However, in large scale studies in Caucasians these polymorphisms seem to influence the risk of having PCOS. Moreover, these studies also showed that some polymorphisms might affect some clinical features of PCOS as well as treatment outcome. Although most research has focussed on the role of FSHR polymorphisms there seems to be also some evidence showing that single nucleotide polymorphisms (SNPs) in the LHCG-Receptor as well as those in FSH-β gene might also alter the phenotype of PCOS. In conclusion most studies confirm that FSHR polymorphisms do alter the phenotype of PCOS in that they either alter the response to exogenous FSH or hat they increase the risk of having PCOS.

Two Hormones for One Receptor: Evolution, Biochemistry, Actions, and Pathophysiology of LH and hCG

LH and chorionic gonadotropin (CG) are glycoproteins fundamental to sexual development and reproduction. Because they act on the same receptor (LHCGR), the general consensus has been that LH and human CG (hCG) are equivalent. However, separate evolution of LHβ and hCGβ subunits occurred in primates, resulting in two molecules sharing ~85% identity and regulating different physiological events. Pituitary, pulsatile LH production results in an ~90-minute half-life molecule targeting the gonads to regulate gametogenesis and androgen synthesis. Trophoblast hCG, the "pregnancy hormone," exists in several isoforms and glycosylation variants with long half-lives (hours) and angiogenic potential and acts on luteinized ovarian cells as progestational. The different molecular features of LH and hCG lead to hormone-specific LHCGR binding and intracellular signaling cascades. In ovarian cells, LH action is preferentially exerted through kinases, phosphorylated extracellular-regulated kinase 1/2 (pERK1/2) and phosphorylated AKT (also known as protein kinase B), resulting in irreplaceable proliferative/antiapoptotic signals and partial agonism on progesterone production in vitro. In contrast, hCG displays notable cAMP/protein kinase A (PKA)-mediated steroidogenic and proapoptotic potential, which is masked by estrogen action in vivo. In vitro data have been confirmed by a large data set from assisted reproduction, because the steroidogenic potential of hCG positively affects the number of retrieved oocytes, and LH affects the pregnancy rate (per oocyte number). Leydig cell in vitro exposure to hCG results in qualitatively similar cAMP/PKA and pERK1/2 activation compared with LH and testosterone. The supposed equivalence of LH and hCG has been disproved by such data, highlighting their sex-specific functions and thus deeming it an oversight caused by incomplete understanding of clinical data.

Treatment strategies for women with polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common endocrine disorder in women, and it is the main cause of infertility in women of reproductive age due to anovulation. PCOS also increases the risk of diseases such as cardiovascular disease and type 2 diabetes in women with this disorder. The mechanism of pathogenesis is not clear, as it may be related to heredity, the environment and internal embryonic factors; thus, the treatment strategies remain unclear. This review summarizes current treatments for PCOS worldwide. Lifestyle modification (LSM) is considered the first-line treatment, regardless of fertility status, without the addition of metformin. Oral contraceptive (OC) pills should be used as a first-line treatment for long-term management for patients with no reproductive requirements. For patients with fertility requirements, ovulation therapy is an effective treatment. For refractory ovulation disorders, patients can choose from among the latest treatments, including ovarian hippocampal signal path block theory, the theory of leptin, inositol treatment, bilateral ovarian drilling to stimulate ovulation and assisted reproductive technology. Because current treatments cannot cure PCOS, lifelong administration is still the mainstream method of management; however, the optimal treatment plan needs further research and exploration.

The tempo of human childhood: a maternal foot on the accelerator, a paternal foot on the brake

Relative to the life history of other great apes, that of humans is characterized by early weaning and short interbirth intervals (IBIs). We propose that in modern humans, birth until adrenarche, or the rise in adrenal androgens, developmentally corresponds to the period from birth until weaning in great apes and ancestral hominins. According to this hypothesis, humans achieved short IBIs by subdividing ancestral infancy into a nurseling phase, during which offspring fed at the breast, and a weanling phase, during which offspring fed specially prepared foods. Imprinted genes influence the timing of human weaning and adrenarche, with paternally expressed genes promoting delays in childhood maturation and maternally expressed genes promoting accelerated maturation. These observations suggest that the tempo of human development has been shaped by consequences for the fitness of kin, with faster development increasing maternal fitness at a cost to child fitness. The effects of imprinted genes suggest that the duration of the juvenile period (adrenarche until puberty) has also been shaped by evolutionary conflicts within the family.

Abnormal expression levels of BMP15/Smad1 are associated with granulosa cell apoptosis in patients with polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common endocrine disorder that affects reproductive dysfunction and metabolism in women of childbearing age. An increasing number of studies have suggested that the bone morphogenetic protein 15 (BMP15) signalling pathway serves an important role in the pathogenesis of PCOS; however, the full mechanism remains unknown. The present study revealed that intrinsic follicular dysplasia may be associated with regulation disorders of ovarian granulosa cell apoptosis. Compared with the control group, body mass index, luteinising hormone and testosterone levels were significantly increased (P<0.05). The percentage of S phase cells was significantly higher, cells in G2/M phase cells was significantly lower, and cells undergoing apoptosis was significantly higher in the PCOS group compared with the control group (P<0.05). The expression levels of B‑cell lymphoma 2 was significantly decreased in granulosa cells of PCOS group, whereas the expression of caspase‑3 was higher than the control group (P<0.05). The rate of apoptosis of granulosa cells was measured by a terminal deoxynucleotide transferase dUTP nick‑end labelling assay. The relative mRNA expression levels of BMP receptor 2 and SMAD1 were significantly decreased in granulosa cells in the PCOS group compared with the control (P<0.05). In addition, the expression of BMP15 in follicular fluid and Smad1 in granulosa cells was significantly decreased in the PCOS group compared with the control (P<0.05). The data suggested that the BMP15/Smad1 signalling pathway may be involved in granulosa cell apoptosis, and may be a target for clinical treatment for PCOS.

Genetics of gonadotropins and their receptors as markers of ovarian reserve and response in controlled ovarian stimulation

Several controlled ovarian stimulation (COS) protocols have been developed to increase the yield of mature oocytes retrieved in assisted reproductive techniques (ARTs). The ovarian reserve (OR) influences the COS response, and it represents the main parameter that helps clinicians in refining clinical treatments in the perspective of a "personalized" ART. This approach is even more needed in particular conditions such as poor OR or polycystic ovary syndrome. Follicle-stimulating hormone, luteinizing hormone, and human chorionic gonadotropin are currently used in COS at different combinations and with different efficacies, even if the best approach definition is controversial. Differences in individual-specific ovarian response to gonadotropin stimulation can be due to alterations of genes encoding for hormones or their receptors. In particular, FSHB c.-211G>T, FSHR p.Asn680Ser, and c.-29G>A SNP allelic combinations may be used as OR and COS response markers. The purpose of this review is to highlight the evidence-based relevance of mutations and polymorphisms in gonadotropins and their receptor genes as predictive markers of OR and COS response to achieve fine-tuned therapeutic regimens.

Polycystic ovary syndrome: analysis of the global research architecture using density equalizing mapping

Polycystic ovary syndrome (PCOS) is the most common cause of female infertility worldwide. Although the related research output is constantly growing, no detailed global map of the scientific architecture has so far been created encompassing quantitative, qualitative, socioeconomic and gender aspects. We used the NewQIS platform to assess all PCOS-related publications indexed between 1900 and 2014 in the Web of Science, and applied density equalizing mapping projections, scientometric techniques and economic benchmarking procedures. A total of 6261 PCOS-specific publications and 703 international research collaborations were found. The USA was identified as the most active country in total and collaborative research activity. In the socioeconomic analysis, the USA was also ranked first (25.49 PCOS-related publications per gross domestic product [GDP]/capita), followed by the UK, Italy and Greece. When research activity was related to population size, Scandinavian countries and Greece were leading the field. For many highly productive countries, gender analysis revealed a high ratio of female scientists working on PCOS with the exception of Japan. In this study, we have created the first picture of global PCOS research, which largely differs from other gynaecologic conditions and indicates that most related research and collaborations originate from high-income countries.

Association between periodontal disease and polycystic ovary syndrome: a systematic review

The purpose of the present study was to review systematically the association between periodontal diseases (PDs) and polycystic ovary syndrome (PCOS). To address the focused question, 'Is there a relationship between PD and PCOS?' indexed databases were searched up to October 2016 without time or language restrictions using different combinations of the following key words: PCOS, ovarian cysts, PD, periodontitis, gingival diseases and gingivitis. Letters to the Editor, commentaries, historic reviews, case-report, unpublished articles and animal/experimental studies were excluded. Seven case-control studies were included. The number of study participants ranged between 52 and 196 females aged between 15 and 45 years. In three and three studies, proinflammatory cytokines were assessed in gingival crevicular fluid and saliva samples, respectively. In one study, salivary microbes were investigated. All studies reported that a positive association exists between PD and PCOS. In conclusion, there is a positive association between PD and PCOS; however, further well-designed longitudinal controlled clinical trials are needed in this regard. It is recommended that physicians should refer patients with PCOS to oral health-care providers for comprehensive oral evaluation and treatment.